最新文献报导 2008 年第 4 期(总第 21 期) 4 2008 中国科学院西安光机所网络信息中心 2008 年 10 月 前 言 根据所领导关于加强我所文献情报服务工作的安排,网络信息中心在 征求部分专家和科技人员对文献的需求和意见后,从 2004 年起,按照我 所的学科布局,不定期地检索和编印《最新文献报导》,在所局域网上发 布并出印刷版本发到各研究室,供有关科技人员参考。在每期的检索与编 辑过程中,我们将广泛听取各方面专业人员的意见,并根据我所学科发展 中有关专业的变化,对文献报导的内容和重心随时调整。您若有最新需 求,请通过 E-mail(ljf@opt.ac.cn)告诉我们,以便随时改进我们的工作。 主办:网络信息中心文献情报服务 编辑:李晋芳 地址:祖同楼 406 房间 电话:88887562 Email:ljf@opt.ac.cn 《最新文献报导》2008 年第 4 期 目 次 前 言 ........................................................................................................................................ 1 光电跟踪 .................................................................................................................................... 1 光纤激光陀螺 ............................................................................................................................ 5 飞秒激光脉冲 ............................................................................................................................ 9 成像光谱 .................................................................................................................................. 14 太阳能电池 .............................................................................................................................. 19 Femtosecond and Attosecond Pulse ......................................................................................... 22 High-Power Laser and Solid-State Laser ................................................................................. 26 Laser Application ..................................................................................................................... 28 Nonlinear Optics ...................................................................................................................... 35 Space Optical System ............................................................................................................... 40 Imaging Spectrometry .............................................................................................................. 46 Tracking of The Moving Target ............................................................................................... 50 Ultraviolet Imaging\Detection.................................................................................................. 52 Optical tweezers/ Photochromic............................................................................................... 56 Fiber Amplifier ......................................................................................................................... 60 Optic Communication .............................................................................................................. 64 Large Aperture Mirror .............................................................................................................. 69 XIOPM latest Documents Report 光电跟踪 1 题名 光电目标图像自动跟踪技术研究 作者 张然;吕高杰;张国华; 单位 总参谋部陆航部驻北京地区军事代表室;中航一集团洛阳电光设备研究所; 中文摘要 概括介绍了相关跟踪、特征跟踪和对比度跟踪等技术,根据各种复杂环境下的算法适应性的需要,提出 了一种改进的相关跟踪算法,即对图像进行粗采样预处理,降低匹配图像的分辨率,再进行图像归一化分区域相关 匹配算法。实验证明,此方法有效地提高了算法的适应性。 刊名 电光与控制 年 2008 期 09 2 题名 基于 EM 的红外扩展目标鲁棒自动跟踪方法 作者 王睿;王原野;王林;陈旭情;祝世平; 单位 北京航空航天大学仪器科学与光电工程学院;中国航天科工集团第三研究院; 中文摘要 针对红外视频图像的特点,提出了一种基于期望最大化算法的红外扩展目标鲁棒自动跟踪方法。首先 利用局部 Top-Hat 形态学滤波进行背景抑制和去噪,并通过平台直方图技术突出跟踪区域的红外目标灰度信息; 然后以考虑了像素空间位置信息的高斯加权直方图建立目标的灰度特征模板;最后通过期望最大化迭代计算来估 计出各密度分布的最大似然函数的参数集,并由此确定跟踪目标的位置和形状尺寸。实验表明,该方法不仅实现 了跟踪窗口随目标尺寸的自适应变化,而且有效克服了红外图像信噪比低的缺点,提高了红外目标实时跟踪的稳 健性。 刊名 红外与激光工程 年 2008 期 04 3 题名 光电跟瞄平台的波门跟踪技术(英文) 作者 邹卫军;薄煜明;陈益; 单位 南京理工大学自动化学院; 中文摘要 波门跟踪是提高基于图像等信息实现跟踪的光电平台跟踪精度的有效方法。探讨了脱靶量预测、图像 传感器滞后和伺服系统动态精度对波门跟踪的影响。针对一类匀速运动目标,建立了基于图像处理信息和伺服系 统反馈信息的目标空间角运动模型,利用最小二乘法获得目标角运动参数的估计,同时推导了目标图像脱靶量的 预测公式,结合目标运动预测,完成了自适应波门的设计。最后给出了常规波门和自适应波门的工程跟踪实验,结 果表明,文中所提方法创新定性地定量分析了波门跟踪技术在工程实践中的问题,解决方案完整且在工程实验中 得到了检验,提高了跟踪的稳定性和系统的实时性。 刊名 红外与激光工程 年 2008 期 04 4 题名 基于格型 IIR 滤波器的自适应陷波器设计 作者 张利;王喜平; 单位 中国船舶重工集团公司第七一○研究所; 中文摘要 给出了基于格型 IIR 滤波器的自适应算法及 2 种自适应步长算法。该自适应陷波器算法具有收敛速度 快、频率跟踪性能好的特点;利用自适应步长代替固定步长后,自适应陷波器的收敛速度明显加快、频率估计精 度明显提高;此外,在原自适应步长的基础之上提出了一种改进的自适应步长算法,采用改进的自适应步长的 IIR 陷波器,实现了窄带噪声和混响背景下的动目标信号检测。仿真结果表明,该算法不仅可以在较低信噪比条件下, 稳定地检测出动目标信号,而且可以估计混响和动目标的频率。 刊名 水雷战与舰船防护 年 2008 期 03 5 题名 大气传输特性对激光测距系统测距精度的影响 最新文献报导 1 XIOPM latest Documents Report 作者 米阳; 单位 中科院长春光机与物理研究所光电测控部; 中文摘要 本文结合光测设备的某次实战任务数据,对激光测距信号在大气中传输的能量衰减机制进行研究,分析 和讨论大气传输特性对激光测距系统精度影响因素,为激光测距系统的设计和进一步的误差修正提供了理论依 据。 刊名 激光杂志 年 2008 期 04 6 题名 卫星激光通信端机跟瞄精度测试技术研究 作者 王建民;秦谊;徐泉;王丽丽; 单位 北京大学电子学系量子信息与测量教育部重点实验室; 中文摘要 卫星激光通信的核心技术是 PAT 技术,即瞄准、捕获、跟踪技术,而实现微弧度量级的跟瞄技术是其中 的关键点和难点。通信端机研制完成后,需要对其各种性能指标进行测试,跟瞄精度是其中的一项重要指标。按 照一般测试原则,跟瞄精度测试装置的精度应达到亚微弧度,并达到几百赫兹的带宽。基于点光源、长焦距透 镜、PZT 器件、平面反射镜及 4 QD 光电器件等,设计并研制了一套能完成通信端机跟瞄精度测试的装置。给出 了测试的基本原理、测试方法、测试装置的结构以及元件参数设计,并推导了椭圆光斑时光斑质心定位算法。实 验数据表明,所研制的测试装置可以达到 3σ=0.37 urad(100 mm 孔径)的测试精度以及优于 250 Hz 的带宽。 刊名 光电子.激光 年 2008 期 08 7 题名 光电经纬仪垂直轴系优化设计 作者 类成华;王守印; 单位 中国科学院长春光学精密机械与物理研究所; 中文摘要 光电经纬仪垂直轴系由于负荷重、转动惯量大,其刚度将直接影响经纬仪的跟踪性能,所以它的方位谐 振频率显得尤为重要.针对这种情况,采用三维软件 UG NX4.0 自身的建模仿真一体化功能,对经纬仪垂直轴系进 行建模、仿真分析,得到了垂直轴系前三阶固有频率及振型.仿真结果满足实际工作需要,符合试验测定值;并且找 到了刚性很好的环节,基于轻量化的考虑,对刚性较好的部件进行尺寸优化设计,在不影响总体结构刚度的情况下, 优化了结构,减轻了重量. 刊名 工程设计学报 年 2008 期 04 8 题名 基于类龙伯格与时滞扰动观测器综合的摩擦补偿 作者 王辉华;刘文化;张世英;刘淼森; 单位 海军装备研究院;海军装备研究院;海军装备研究院;海军装备研究院; 中文摘要 针对摩擦扰动的非线性特性及传统摩擦补偿方法的不足,利用 LuGre 动态摩擦模型对摩擦现象描述的 准确性,分析了类龙伯格状态观测器及时滞扰动观测器的设计过程,提出了综合类龙伯格状态观测器与时滞扰动 观测器的摩擦补偿方案。从实验结果看,利用类龙伯格状态观测器观测摩擦状态,并通过 LuGre 模型估计摩擦扰 动起到了较好的摩擦扰动抑制作用,解决了时滞扰动观测器用于摩擦补偿的扰动慢时变限制的问题。同时,TDE 扰动观测器不仅消除了摩擦扰动补偿残差,而且起到了抑制了外界扰动的作用。 刊名 光电工程 年 2008 期 08 9 题名 角度无静差陀螺稳定光电探测平台设计与实现 作者 韩永根; 单位 北京航空航天大学仪器科学与光电工程学院; 中文摘要 应用于地面战车的高精度陀螺稳定和跟踪装置在开炮瞬间会受到强烈冲击,易造成陀螺损坏及平台翻 台。针对此问题,选用抗冲击力强的光学速率陀螺作为敏感元件,并针对速率陀螺反馈加传统 PID 控制不能实现 稳定角度无静差的问题,尝试了一种 PII2(比例+积分+二重积分)加前置滤波的校正形式,通过极点配置的方法设计 最新文献报导 2 XIOPM latest Documents Report 了平台速度稳定环与位置指令环。在 3000gcm 干扰力矩的作用下,动态误差为 30″,静态角误差为零。结果表明, 采用 PII2 的控制结构,提高了系统的稳定刚度和稳态精度。 刊名 光电工程 年 2008 期 08 10 题名 光电设备中并行数据接口分析 作者 刘鑫;宋晓明;陈方斌; 单位 西安应用光学研究所,西安应用光学研究所,西安应用光学研究所, 中文摘要 本文研究了光电跟踪仪采控单元和加固机之间的并行接口电路情况,分析了信号长线传输的于扰因素, 并给出了相应的抗于扰措施。最后提出了采用光电隔离器件的并口隔离实施方案,并进行了实验验证。 刊名 电子设计应用 年 2008 期 02 12 题名 红外动目标识别跟踪系统硬件设计与实现 作者 贾雅琼; 单位 湖南工学院 衡阳 421008 中文摘要 本文论述红外动目标识别跟踪系统的具体实现及相关理论分析,重点在于该系统的硬件模块实现及分 析,并针对系统的可靠性进行了讨论。 刊名 电子产品世界 年 2008 期 04 14 题名 移动机器人运动控制系统研究 作者 叶锦华;吴海彬;陈天炎; 单位 福州大学机械工程及自动化学院,福州大学机械工程及自动化学院,福州大学机械工程及自动化学院 福州 350002,福州 350002,福州 350002 中文摘要 研究了一种(2,0)型受非完整约束的移动机器人运动控制系统,其一驱动轮采用主动控制,而另一驱动轮 保持实时跟踪,该双闭环结构实现了移动机器人的调速控制和准确定位。此外为了进一步提高控制效果,并能适 应存在一定非线性、时变和时滞性的移动机器人系统,对其控制器引入了专家 PID 控制算法,实验证明该运动控 制器控制的有效性。 刊名 机械设计与制造 年 2008 期 06 15 题名 三轴光电跟踪系统对地平式天顶盲区出入点的判定方法 作者 刘兴法; 单位 中国科学院光电技术研究所 四川成都 610209 中文摘要 三轴光电跟踪系统可以全方位跟踪空间目标,在地平式光电跟踪系统天顶盲区内通过转动 X 轴实现快 速高精度跟踪。用多种三轴光电跟踪系统对地平式天顶盲区进行判定,包括目标距离信息判定方式、Z 轴转动速 度判定方法、预置盲区判定方法等。判定方法的选择直接影响三轴光电跟踪系统的跟踪精度。理论分析和仿真 表明:以 Z 轴的最大保精角速度来判定地平式盲区的出入点使三轴系统在天顶附近有更高的跟踪精度,且可实现 跟踪方式的平稳过渡。 刊名 应用光学 年 2008 期 04 16 题名 多引导源在光电经纬仪跟踪系统中的应用 作者 刘铁军;杨小军;彭伟; 单位 中国科学院西安光学精密机械研究所,中国科学院西安光学精密机械研究所,中国科学院西安光学精密机械 研究所 西安 710019 中国人民解放军 63861 部队 60-1 分队,白城 137001,西安 710019,西安 710019 最新文献报导 3 XIOPM latest Documents Report 中文摘要 在某姿态测量系统中,伺服系统控制经纬仪在方位和俯仰两个自由度运动对目标进行实时跟踪。测量 分站主控计算机首先通过接收外部引导信息快速将目标引入捕获电视视场,当脱靶量信息稳定后切入电视跟踪模 式。当目标位置超出捕获电视作用距离后,重新切换到外引导模式,并进行必要的地球曲率修正,保证测量电视系 统对目标的连续成像。实际应用证明,多种引导源可以相互补充,扩展系统的捕获和跟踪能力,提高跟踪精度。 刊名 科学技术与工程 年 2008 期 15 17 题名 一种基于光电经纬仪的数据预测跟踪技术 作者 苏秀琴;郝伟;李哲; 单位 中国科学院西安光学精密机械研究所,中国科学院西安光学精密机械研究所,中国科学院西安光学精密机械 研究所 西安 710119 中国科学院研究生院,北京 100039,西安 710119 中国科学院研究生院,北京 100039,西安 710119 中国科学院研究生院,北京 100039 中文摘要 针对光电经纬仪上的跟踪器,提出了一种基于合成角数据的预测跟踪技术.利用目标的前几帧脱靶量和 对应的经纬仪角度信息计算合成角,再以前几帧合成角数据为依据,利用线性动态模型推导出下一帧的合成角信 息,计算出目标在图像中的位置,从而实现了对目标的预测跟踪.实验证明,该方法可以实现预测跟踪,减小处理区域, 提高跟踪器的处理速度,有效地避免波门外虚假目标的干扰. 刊名 光子学报 年 2008 期 07 18 题名 某导引头陀螺进动控制理论研究 作者 魏文俭;秦石乔;张宝东;李华; 单位 国防科学技术大学光电科学与工程学院,国防科学技术大学光电科学与工程学院,中国人民解放军 91404 部 队,中国人民解放军 63880 部队 长沙 410073,长沙 410073,河北秦皇岛 066070,河南洛阳 471003 中文摘要 为实现精确控制某型号导引头搜索和跟踪目标,从理论上推导和分析了该导引头中陀螺仪的运动控制 方法。分析了该型号导引头中陀螺仪的结构、特点、作用与工作原理。根据陀螺技术方程和导引头的陀螺仪结 构特点建立了陀螺运动模型。在建立弹体坐标系以及莱查坐标系的基础上,通过分析陀螺仪在给定的典型电流作 用下所受的控制力矩,推导和分析了陀螺仪的运动规律。通过上面的推导和分析,得到结论:只有与陀螺转子转动 频率相同的交流电流才能作为跟踪进动电流;进动方向由进动电流的初始相位决定。同时给出了陀螺转子在典型 电流作用下的顶点轨迹。为精确控制该导引头中陀螺仪的运动提供了理论依据。 刊名 电光与控制 年 2008 期 08 19 题名 基于液晶光阀的数字仿真目标研究 作者 武晓阳;贺庚贤; 单位 长春光学精密机械与物理研究所,长春光学精密机械与物理研究所, 中文摘要 室内检测光电跟踪测量设备的电视系统,关键是提供适合的仿真目标。用液晶光阀作为成像平行光管 的目标板,实时显示计算机控制的数字仿真目标图形;在外光源的照射下,平行光管将液晶光阀显示的图形成像于 无穷远,提供给被测光电跟踪测量设备。用计算机生成的数字仿真目标可以在形状、大小、数量、背景及对比度 等方面满足光电跟踪测量设备的检测需求。仿真目标的形成方便、灵活,克服了原有平行光管目标的固有缺陷。 刊名 微计算机信息 年 2008 期 22 20 题名 舰载平台下的光电跟踪技术 作者 沈永良;徐亚飞; 单位 华中光电技术研究所,华中光电技术研究所 湖北武汉 430073,湖北武汉 430073 中文摘要 针对舰载近程舰炮武器系统振动、烟雾等使用环境,提出了基于目标航迹滤波算法及舰炮火控技术相 结合的光电记忆跟踪技术,并在某型舰载近程舰炮武器系统中应用,应用分析表明,此技术大大提高了光电在舰炮 射击时的跟踪稳定性,也为后续解决高频振动和炮口烟雾等对光电跟踪影响提供了思路。 最新文献报导 4 XIOPM latest Documents Report 刊名 火力与指挥控制 年 2008 期 07 光纤激光陀螺 21 题名 基于 GPS 的计算机图像跟踪摄取系统的研究与设计 作者 彭嵩;肖建秋;马青芳;田毅; 单位 中国石油集团钻井工程技术研究院钻井机械研究所;中国石油集团钻井工程技术研究院钻井机械研究所; 中文摘要 基于 GPS 的计算机图像跟踪摄取系统是一个集跟踪、记录运动目标轨迹、实时图形传输的多功能装 备,实际上是一种全数字的小型经纬仪系统,其主要用途是飞行目标的外弹道跟踪和实况记录;本着"适用、可靠、 先进、经济"的原则,系统采用了成熟先进的数字化技术,实现了设备的集成化和小型化,确保了系统的高可靠性; 经实验验证,系统达到了设计要求,具有很强的鲁棒性,对该系统的研究具有重要的理论研究意义和实际应用价 值。 刊名 计算机测量与控制 年 2008 期 08 22 题名 用于高精度光纤陀螺的光纤放大器光源 作者 王瑞;李绪友;张勇; 单位 哈尔滨工程大学自动化学院; 中文摘要 介绍了应用于光纤陀螺的掺铒光纤超荧光光源的研究现状,比较分析了掺铒光纤光源 5 种主要结构的 优缺点,在此基础上得出了光纤放大器结构的光源既可以有效提高光纤陀螺的检测精度和稳定性,又可以降低成 本。针对光纤放大器光源,分别分析了泵浦功率、泵浦波长、反馈以及铒纤温度对其平均波长稳定性的影响。为 了消除反馈对光纤放大器光源平均波长稳定性的影响,根据超荧光光源的偏振态效应,在光源中加入了偏振器来 控制反馈的偏振态,从而降低了反馈对光源平均波长稳定性的影响,并采用长周期光纤光栅作为滤波器,有效地提 高了光纤放大器光源的波长稳定性。 刊名 红外与激光工程 年 2008 期 04 23 题名 机械抖动对机抖激光陀螺稳频装置的影响 作者 万顺平;李峰;王小飞;朱强; 单位 北京自动化控制设备研究所; 中文摘要 分析了机抖激光陀螺中偏频系统通过机械抖动对稳频装置施加作用力的影响。此力主要通过沿抖动切 线方向调制卡盘组件,并改变环形腔腔长,引起激光频率相对变化达 10-7 量级。实验表明,激光功率调制量随着卡 盘组件质量增大和偏频量增加而增加,从而影响零偏稳定性。提高卡盘在抖动切线方向的刚度,减少其质量或采 用丝杆与槽片点接触等技术措施,能减少机械抖动对稳频装置的影响,另外,对机抖陀螺应选择合适的偏频量。 刊名 红外与激光工程 年 2008 期 04 24 题名 光纤陀螺随机误差特性仿真与辨识 作者 葛升民;边志强;韩军良;王晖; 单位 哈尔滨工业大学控制科学与工程系; 中文摘要 分析了光纤陀螺的各项随机误差特性,给出了各项随机噪声的仿真方法.运用不同的随机过程模拟各种 随机噪声,采用正交小波变换的方法模拟 1/f 噪声,用白噪声一次离散积分的方法模拟速率随机游走噪声,用一阶马 尔可夫过程模拟指数相关噪声,并给出了仿真结果.提出了基于 Allan 方差、小波分析和功率谱密度的随机误差辨 识方法,对光纤陀螺的随机误差特性进行了辨识研究. 刊名 测试技术学报 年 2008 期 04 最新文献报导 5 XIOPM latest Documents Report 25 题名 基于模糊 PID 的光纤陀螺光源光控技术研究 作者 南书明; 单位 白城师范学院; 中文摘要 为了提高光纤陀螺光源的稳定性,该文在陀螺系统基础上提出了一种光源光功率控制方案。采集陀螺 耦合器空端上的光功率信号来反馈控制陀螺光源的出纤光功率。在反馈控制算法上采用模糊 PID 控制,其具有较 好的灵活性、适应性及较快的响应。测试结果表明,采用模糊 PID 的光控方案比未采用光控的光源驱动方案在光 源出纤光功率的稳定性上提高了 66%。 刊名 压电与声光 年 2008 期 05 26 题名 基于 VSCMG 的卫星姿态控制仿真系统 作者 戴路;金光;陈涛; 单位 中国科学院长春光学精密机械与物理研究所; 中文摘要 介绍了一种新型卫星姿态控制全物理仿真系统,此仿真系统以长春光机所最新研制的高精度三轴气浮 转台为平台,采用变速控制力矩陀螺(VSCMG)为主要控制执行机构,并结合喷气推力机构作为系统的辅助执行机 构给控制力矩陀螺进行卸载。此系统应用高精度光纤陀螺、高精度倾角传感器和磁强计等姿态确定器件构成一 套完整的姿态控制全物理仿真系统。介绍了整个仿真系统的软硬件构成,并结合传感器和执行机构参数进行建模 和误差分析。本仿真系统可以为一般卫星姿态控制,尤其是以 VSCMG 为主要执行机构的敏捷型小卫星的姿态控 制策略和算法提供良好的仿真验证平台。 刊名 光学精密工程 年 2008 期 08 27 题名 数字闭环光纤陀螺仪过调制技术研究 作者 顾宏;赵启大;杨功流; 单位 南开大学现代光学研究所;天津航海仪器研究所; 中文摘要 针对光纤陀螺噪声的特点,提出了一种采用增加偏置调制深度的办法提高光纤陀螺信噪比,虽然陀螺理 论灵敏度有所降低,但是陀螺的长期漂移即零偏稳定性却获得了明显提高。这种方法我们称之为过调制技术。对 基于数字闭环调制解调方案的过调制技术改善陀螺信噪比的理论基础进行了深入的分析,在此基础上进行了相关 的实验研究。理论分析和实验结果均表明,当调制深度处于π/2 与π之间的某个值时,光纤陀螺具有最佳性能。 相比于传统的π/2 偏置点,采用过调制技术后的光纤陀螺的零偏稳定性获得了数倍的提高。 刊名 光电子.激光 年 2008 期 08 28 题名 光纤陀螺温度误差建模及补偿方法 作者 李战;冀邦杰;国琳娜;洪剑英; 单位 水下信息处理与控制国家重点实验室;中国船舶重工集团公司第 705 研究所; 中文摘要 温度是影响光纤陀螺输出精度的主要误差源。为了有效提高光纤陀螺的输出精度,在光纤陀螺温度特 性理论分析的基础上,对光纤陀螺进行了全温度范围(-30℃~+70℃)速率试验和零偏试验,并对试验数据进行了深 入分析,建立了光纤陀螺温度与标度因数、温度与零偏之间的多项式误差补偿模型。试验结果表明,该温度误差 补偿模型可以使光纤陀螺在全温度范围的输出精度提高一个数量级,补偿效果良好。 刊名 鱼雷技术 年 2008 期 04 29 题名 基于对称方波调制的光纤陀螺本征频率自动测试方法 作者 周友伟;刘铁根;李茂春;侯丽丽;姚晓天; 最新文献报导 6 XIOPM latest Documents Report 单位 天津大学精仪学院光电信息技术科学教育部重点实验室;天津大学精仪学院光电信息技术科学教育部重点 实验室;天津大学精仪学院光电信息技术科学教育部重点实验室;天津大学精仪学院光电信息技术科学教育部重 点实验室;天津大学精仪学院光电信息技术科学教育部重点实验室; 中文摘要 从光纤陀螺的调制原理出发,采用频率为光纤环本征频率的 1/2 的对称方波对 Y 波导进行调制,分析光 纤陀螺的输出信号,得到输出的方波信号的占空比与调制频率的对应关系,通过数据采集卡将占空比转化为方波 上下峰值点数差的问题,并以此点数差作为反馈量调节对 Y 波导的调制频率实现对本征频率的自动锁定。该方 法已在工程实践中得到应用,试验结果表明该测试方法可在几秒中之内完成而且测试精度可达 0.01kHz。与已有 的测量方法相比,基于对称方波调制的测试方法具有更高的精度、高速、数字化和易于实现自动测量。 刊名 激光与红外 年 2008 期 07 30 题名 精密超精密加工技术在航天领域的应用与展望 作者 刘俊利;刘伟; 单位 北京兴华机械厂,北京兴华机械厂, 中文摘要 从航天产品对精密加工的需求出发,综合论述了国内外精密加工技术的发展现状,并提出了航天精密加 工技术发展和研究的重点。 刊名 航天制造技术 年 2008 期 04 31 题名 光纤陀螺发展及其在制导武器中的应用 作者 李园晴; 单位 中国空空导弹研究院 河南洛阳 471009 中文摘要 本文分析了 sagnac 效应光纤陀螺的基本理论和工作原理,介绍了其构成方式,并简单阐述了光纤陀螺的 发展现状及在制导武器中的应用。 刊名 科技经济市场 年 2008 期 07 32 题名 三轴一体化光纤陀螺光源驱动技术 作者 徐长彬;刘军;鲁军;秦勇; 单位 军械工程学院,军械工程学院,军械工程学院,中国人民解放军第 78666 部队 河北石家庄 050003,河北石家庄 050003,河北石家庄 050003,云南 652102 中文摘要 根据三轴一体化光纤陀螺共享光源,要求光源能够提供较大的高精度的恒流以满足实际需要。结合 SLD(超辐射发光二极管)光源结构特点及其工作原理,采用恒流和温控方案,设计了新的高精度恒流驱动和温度控 制系统。经测试结果表明,设计的系统能够在环境温度为-45℃~70℃内稳定工作,实现了高精度恒流和温度驱动 控制,满足三轴一体化光纤陀螺对光源驱动的要求。 刊名 仪表技术 年 2008 期 08 33 题名 基于遗传算法的 BP 网络的优化设计方法 作者 张磊;尹文龙;张颔; 单位 军械工程学院科研部,军械工程学院计算机基础教研室,军械工程学院计算机基础教研室 石家庄 050003,石 家庄 050003,石家庄 050003 中文摘要 针对 BP 网络存在易陷入局部极小和收敛速度慢的问题,采用遗传算法(GA)优化 BP 网络;并采用混配的 方法,对遗传算法进行了改进,克服了遗传算法中所存在的种群内过早收敛的缺点,并在光纤陀螺温度漂移建模中, 取得了较好预测的效果。 刊名 科学技术与工程 年 2008 期 14 最新文献报导 7 XIOPM latest Documents Report 34 题名 激光陀螺光电探测器光窗的设计 作者 胡志强;姚合宝;蒋军彪;王松伟;朱冠芳; 单位 西北大学物理学系,西北大学物理学系,西安北方捷瑞光电科技有限公司,西北大学物理学系,西北大学物理学 系 陕西西安 710069,西安北方捷瑞光电科技有限公司,陕西西安 710000,陕西西安 710069,陕西西安 710000,陕西 西安 710069,西安北方捷瑞光电科技有限公司,陕西西安 710000,陕西西安 710069 中文摘要 用平面波计算拍频条纹间距时,因激光器中存在衍射效应,且实际光强分布为高斯型,故给光电探测器光 窗尺寸计算带来很大误差(40%),导致系统不能正常工作。为此,以高斯光束为基础,利用光电探测器测得 2 路信号 的相位差,通过数值计算得到 2 束光拍频条纹间距,由此计算得到理想相位差光电探测器的尺寸。最后,用实验验 证了该设计方法的可行性,为 RLG 光电探测器光窗尺寸的设计提供了一种简单准确的方法。 刊名 应用光学 年 2008 期 04 35 题名 激光陀螺抖动偏频优化研究 作者 陈林峰;严吉中;韩宗虎;陈勇;吉翠萍;雷建军;赵小宁; 单位 西北工业大学,飞行自动控制研究所,西北工业大学,西北工业大学,西北工业大学,飞行自动控制研究所,飞行 自动控制研究所 西安 710072,西安 710065,西安 710072,西安 710072,西安 710072,西安 710065,西安 710065 中文摘要 基于频率调制理论,分析、仿真计算了正弦抖动偏频和优化后的正弦抖动偏频条件下,激光陀螺输入-输 出曲线的特点.结果表明:正弦抖动偏频时激光陀螺的输入-输出曲线在抖动频率的倍频点处存在着动态锁区,其宽 度与激光陀螺静态锁区、抖动角振幅有关.采用优化后的正弦抖动偏频可以很好地克服动态锁区,大大提高激光 陀螺输入-输出曲线的线性度.试验对比了正弦抖动偏频和优化后的正弦抖动偏频条件下激光陀螺的输出性能.试 验结果表明:采用优化后的正弦抖动偏频显著提高了陀螺准确度. 刊名 光子学报 年 2008 期 07 36 题名 激光陀螺噪音特性试验研究 作者 韩宗虎;郭昕;陈林峰; 单位 西北工业大学,西北工业大学,西北工业大学 西安 710072,西安 710072,西安 710072 中文摘要 给出了激光陀螺噪音分析方法及噪音模型,据此模型比较研究了四种激光陀螺在不同解调方案下噪音 组成分量之间的关系;理论分析了激光陀螺噪音分量的特性和引起该噪音分量的因素,给出了典型的试验数据和 曲线.研究结果表明,该模型不但可以用于对激光陀螺的随机游走系数的估计.而且,该模型的其他系数可以用于研 究陀螺的量化和解调误差,也能用于评估陀螺输出的速率噪音. 刊名 光子学报 年 2008 期 07 37 题名 光纤陀螺的离散动态温度模型 作者 周海波;刘建业;赖际舟;熊智; 单位 南京航空航天大学导航研究中心,南京航空航天大学导航研究中心,南京航空航天大学导航研究中心,南京航 空航天大学导航研究中心 江苏南京 210016,空军飞行试验训练基地,河北沧州 061022,江苏南京 210016,江苏南京 210016,江苏南京 210016 中文摘要 光纤陀螺漂移的温度模型可分为静态温度模型和动态温度模型.通过控制温控箱的温度变化率,对光纤 陀螺进行温度实验,建立其漂移的静态、动态温度模型,以研究温度、温度变化率和温度梯度对光纤陀螺漂移的 影响.研究结果表明,温度变化率和温度梯度对光纤陀螺漂移的影响不容忽视;考虑了温度和温度变化率(或温度梯 度)的动态模型的补偿精度比单纯考虑温度的静态模型提高了 50%.因此在对光纤陀螺建立温度模型时,应该建立 动态温度模型,以取得较好的补偿效果. 刊名 应用科学学报 年 2008 期 04 最新文献报导 8 XIOPM latest Documents Report 38 题名 基于 4 态马尔可夫链的光纤陀螺随机调制 作者 金靖;李敏;宋凝芳;张春熹; 单位 北京航空航天大学仪器科学与光电工程学院,北京航空航天大学仪器科学与光电工程学院,北京航空航天大 学仪器科学与光电工程学院,北京航空航天大学仪器科学与光电工程学院 北京 100191,北京 100191,北京 100191, 北京 100191 中文摘要 在数字闭环光纤陀螺中,由调制信号引起的电串扰(即调制串扰)会导致零偏稳定性、死区和线性度等指 标恶化.为了消除调制串扰信号的影响,提出了基于 4 态马尔可夫链的随机调制方法.将一个 4 状态马尔可夫链引 入到随机调制中,该马尔可夫链利用正弦函数的周期性和状态转移方向的等概率性,产生出了相互统计独立的调 制信号和解调信号,由于解调信号为等概率取值-1,1 的零均值随机序列,所以在理想情况下调制信号及电串扰信号 和解调信号相关的结果为零.仿真和实验结果表明,基于 4 态马尔可夫链的随机调制方法对调制串扰信号的抑制 可达 1×103 倍,消除了调制串扰信号对陀螺零偏稳定性、死区和线性度等指标的影响. 刊名 北京航空航天大学学报 年 2008 期 07 39 题名 一种复用型光纤陀螺的设计与实现 作者 张琛;李绪友;王玉柯;王珺; 单位 哈尔滨工程大学自动化学院,哈尔滨工程大学自动化学院,驻九江地区军代表室,哈尔滨工程大学自动化学院 哈尔滨 150001,哈尔滨 150001,江西九江 332000,哈尔滨 150001 中文摘要 描述了单光源、单检测器、单信号处理板的多轴光纤陀螺系统结构,分析了现有其它调制方案所存在 的缺陷,提出了一种基于时分多路技术的新型的方波偏置调制与解调方案。该方案的优点在于能够在各轴陀螺返 回光功率不平衡的情况下保持偏置功率的恒定性,并有效地减小因器件复用所产生的各种串扰、信号波动对系统 性能造成的影响。建立了系统的试验样机。在降低了多轴光纤陀螺的体积、重量和成本的同时也在一定程度上 提高了系统的可靠性。 刊名 传感技术学报 年 2008 期 07 40 题名 具有安装误差抵偿功能的光纤陀螺/全站仪组合定向方法 作者 于先文;王庆;郑子扬; 单位 东南大学仪器科学与工程学院,东南大学仪器科学与工程学院,东南大学仪器科学与工程学院 南京 210096, 东南大学交通学院,南京 210096,南京 210096,南京 210096 中文摘要 为实现在单个 GPS 控制点上直接完成角秒级的全站仪定向,提出了一种基于光纤陀螺的免安装误差标 定全站仪定向方法.在该方法中,光纤陀螺与全站仪望远镜固连,利用全站仪望远镜带动光纤陀螺分别在水平面和 竖直面精确旋转 180°,到东向位置、东向抵偿位置、西向位置、西向抵偿位置做静态测量.在给出 4 个位置严密 观测方程的基础上,利用 4 个位置的测量值,得到忽略安装误差影响情况下的全站仪横轴真方位角计算公式,实现 光纤陀螺轴与全站仪横轴间的安装误差自动抵消.在充分考虑到工程实现可行性的情况下进行了仿真研究,结果 表明:该方法在不利的情况下,给方位角带来的误差约为 17″,在指南针的辅助下可控制在 10″以内,该精度能够 满足日常测量工作需要. 刊名 东南大学学报(自然科学版) 年 2008 期 04 飞秒激光脉冲 41 题名 用飞秒激光在石英玻璃体内写入光波导和光栅的研究 作者 高仁喜;郑杰;曲士良;韩艳华; 单位 哈尔滨工业大学(威海)光电科学系;吉林大学电子科学与工程学院集成光电子国家重点实验室; 中文摘要 用飞秒激光在石英玻璃写入了光波导和光栅等结构。飞秒激光辐射照形成波导效应时的折射率改变量 为 0.001 至 0.008。折射率的改变量依赖于飞秒激光脉冲辐照的剂量和功率密度。通过 Raman 光谱和 AFM 图像, 研究了波导区的物质结构变化,并对飞秒激光写入过程的物理机制进行了探讨。 刊名 激光杂志 最新文献报导 9 XIOPM latest Documents Report 年 2008 期 04 42 题名 微结构光纤次芯中的四波混频过程 作者 季玲玲;陆培祥;陈伟;戴能利;张继皇;蒋作文;李进延;李伟; 单位 华中科技大学武汉光电国家实验室激光科学与技术研究部;武汉烽火通信科技股份有限公司;清华大学精密 仪器与机械学系; 中文摘要 利用 Ti:sapphire 飞秒激光脉冲在微结构光纤包层的次芯中通过参量四波混频效应获得 480—550nm 的 反斯托克斯波,转换效率可高达 28%.通过改变输入光的偏振方向可以调节反斯托克斯波的中心波长.理论模拟了 飞秒激光在次芯中的模式特性和色散特性,较好地解释了实验结果. 刊名 物理学报 年 2008 期 09 43 题名 啁啾飞秒激光脉冲在 ZK7 玻璃中成丝传输的物理特性 作者 杨建军;杨阳;王锐;韩伟; 单位 南开大学现代光学研究所光电信息技术科学教育部重点实验室; 中文摘要 采用具有不同初始负啁啾量的飞秒激光脉冲,研究了其在 ZK7 玻璃中非线性成丝传输的物理特性.实验 表明激光成丝的阈值功率随着脉冲初始啁啾量的增大而升高,但啁啾导致的光学细丝长度将逐渐变长.通过光丝 超连续谱的测量与分析,发现了啁啾激光成丝过程中等离子体的非线性作用随着初始啁啾量的增大而减弱,并在 较长空间距离内形成了非电离特性占主导的光学成丝的新现象.另外,实验观察到了啁啾脉冲激光成丝过程中的 多光丝干涉图像,理论分析和讨论了非电离光学成丝的物理机制.这些研究结果表明初始啁啾量对于超短激光脉 冲成丝过程将起到至关重要的作用. 刊名 中国科学(E 辑:技术科学) 年 2008 期 09 44 题名 光子晶体光纤中飞秒激光脉冲传输研究 作者 来耀兵; 单位 陕西工业职业技术学院 陕西咸阳 712000 中文摘要 为更精细地描绘飞秒光脉冲在光子晶体光纤中的传输和演化,用分步傅里叶方法求解广义非线性薛定 谔方程(GNSE)的基础上,研究了光纤参量随脉冲峰值频移的变化.模拟了飞秒光脉冲在光子晶体光纤中传输和演 化的过程.研究发现:光纤色散和强非线性对飞秒脉冲在光子晶体光纤中传输、演化以及超连续谱的展宽有很大 影响. 刊名 光子学报 年 2008 期 08 45 题名 基于刀片法的飞秒激光束腰半径的实时测量与计算 作者 韩秋菊;吴文智; 单位 东北农业大学理学院生物物理系,黑龙江大学电子工程学院 黑龙江哈尔滨 150030,黑龙江哈尔滨 150080 中文摘要 利用 LabVIEW 软件编程,使用数据采集卡配合光功率计,通过刀片切割光束的方法测量并计算了经过 凸透镜的飞秒脉冲激光的束腰半径。对光功率随刀片位置变化的关系进行拟合,可以在线实时测量精确度为微米 量级的激光束腰半径。对经过会聚透镜焦点附近的飞秒激光束腰半径进行了测量,发现在焦点之前束腰半径随位 置的变化满足经过焦点后测量的束腰半径偏大,这主要是由于飞秒激光聚焦后峰值功率极大,对刀刃产生了破坏 作用。 刊名 自动化博览 年 2008 期 07 46 题名 高脉冲能量大模场面积光子晶体光纤飞秒激光器 作者 宋有建;胡明列;张弛;柴路;王清月; 最新文献报导 10 XIOPM latest Documents Report 单位 天津大学精密仪器与光电子工程学院超快激光研究室 光电信息技术科学教育部重点实验室,天津大学精密 仪器与光电子工程学院超快激光研究室,光电信息技术科学教育部重点实验室,天津大学精密仪器与光电子工程 学院超快激光研究室,光电信息技术科学教育部重点实验室,天津大学精密仪器与光电子工程学院超快激光研究 室,光电信息技术科学教育部重点实验室,天津大学精密仪器与光电子工程学院超快激光研究室,光电信息技术科 学教育部重点实验室,,天津 300072,天津 300072,天津 300072,天津 300072,天津 300072 中文摘要 报道了一种支持高单脉冲能量输出的被动锁模飞秒光纤激光器.该激光器使用具有极低非线性系数的 掺 Yb3+双包层大模场面积偏振光子晶体光纤作为激光增益介质,具有很好的环境稳定性.激光器基于线形腔结构, 没有色散补偿,利用半导体可饱和吸收镜(SESAM)实现自启动锁模,获得了平均功率为 2.5W,重复频率为 51.4 MHz(对应于 50nJ 的单脉冲能量),脉冲宽度为 4.2ps 的稳定的连续波锁模脉冲输出.经腔外色散补偿,脉冲宽度压 缩至 410fs.当激光器输出功率比较低时,脉冲成形由 SESAM 的非线性吸收决定,而在高功率输出的情况下,激光器 的锁模运转主要取决于自相位调制展宽光谱与增益带宽的限制之间的平衡. 刊名 科学通报 年 2008 期 13 47 题名 飞秒光镊技术及其发展 作者 杨海峰;周明;戴娟;狄建科;赵恩兰;蔡兰; 单位 江苏大学光子制造科学中心,江苏大学光子制造科学中心,江苏大学光子制造科学中心,江苏大学光子制造科 学中心,江苏大学光子制造科学中心,江苏大学光子制造科学中心 江苏 镇江 212013,江苏 镇江 212013,江苏 镇江 212013,江苏 镇江 212013,江苏 镇江 212013,江苏 镇江 212013 中文摘要 激光捕获技术是利用光辐射力来捕捉、移动和操纵微粒的先进技术。飞秒光镊在实现粒子微纳操纵的 同时还伴随着非线性现象的发生。阐述了飞秒光镊的模型和原理以及系统的各种结构形式,包括单光束梯度力光 阱、贝塞耳光阱、双光束光纤光阱和冲击波光阱几种形式,并分析了每种形式的特点。 刊名 光学技术 年 2008 期 04 48 题名 超快光纤激光器提供灵活解决方案 作者 崔锦江; 单位 中文摘要 超快锁模激光器可以产生皮秒和飞秒激光脉冲。为了使超快激光技术的应用领域进一步拓展,激光器 系统的操作必须更加简单,成本也必须降低。实现这 2 项目标的关键因素就是从固态激光器向光纤激光器转化。 刊名 光机电信息 年 2008 期 07 49 题名 基于光子晶体光纤飞秒激光放大器的微纳加工系统 作者 巫殷忠;刘博文;宋有建;胡明列;贾威;王清月; 单位 天津大学精密仪器与光电子工程学院超快激光研究室光电信息技术科学教育部重点实验室,天津大学精密 仪器与光电子工程学院超快激光研究室光电信息技术科学教育部重点实验室,天津大学精密仪器与光电子工程学 院超快激光研究室光电信息技术科学教育部重点实验室,天津大学精密仪器与光电子工程学院超快激光研究室光 电信息技术科学教育部重点实验室,天津大学精密仪器与光电子工程学院超快激光研究室光电信息技术科学教育 部重点实验室,天津大学精密仪器与光电子工程学院超快激光研究室光电信息技术科学教育部重点实验室 天津 300072,天津 300072,天津 300072,天津 300072,天津 300072,天津 300072 中文摘要 以掺镱大模面积光子晶体光纤(PCF)飞秒激光放大器为光源组建了一套结构紧凑且运行稳定的飞秒激 光微纳加工系统,中心波长为 1040 nm,重复频率 50 MHz,最大平均功率 16 W,光栅压缩后脉冲宽度 85 fs。利用该 套系统在硅片、金属薄膜(Cr 膜、Al 膜)上演示了微图案的刻划,并与采用重复频率 1 kHz 的固体钛宝石飞秒激光 放大器的加工结果进行对比,发现利用新组建的加工系统进行微纳加工,由于单脉冲能量较小且便于调节,使得刻 划微图案时边缘加工效果更容易控制,且避免了加工过程中未加工区域受到的污染,保护了制作衬底。显示了该 套系统高重复频率和高平均功率的特性及其在改善微纳加工效果及明显提高加工效率方面的优势。 刊名 中国激光 年 2008 最新文献报导 11 XIOPM latest Documents Report 期 07 50 题名 基于多台阶反射光栅的飞秒脉冲压缩装置 作者 贾伟;周常河;戴恩文; 单位 中国科学院上海光学精密机械研究所信息光学实验室,中国科学院上海光学精密机械研究所信息光学实验 室,中国科学院上海光学精密机械研究所信息光学实验室 上海 201800,中国科学院研究生院,北京 100039,上海 201800,上海 201800 中文摘要 反射式光栅对是一种具有负色散性质的器件,可用于飞秒激光脉冲的压缩和展宽,具有无材料色散的优 点。给出了一种基于多台阶反射光栅的脉冲压缩装置。该装置为倍密度光栅结构,由两个周期分别为 40μm 和 20μm 的四台阶反射式光栅组成。实验得到的衍射效率可以达到 70%以上,输入脉冲经过两个光栅的衍射后会按 原路返回,从而达到色散补偿的效果。利用此压缩装置,脉冲宽度为 66.8 fs 的输入脉冲压缩至接近傅里叶变换极 限脉冲,即 46.6 fs,由此证明只要多台阶光栅效率足够高,此装置就有可能成为不同于棱镜对进行飞秒脉冲腔内和 腔外压缩的另一种途径。 刊名 中国激光 年 2008 期 07 51 题名 微结构光纤正常色散区飞秒激光脉冲传输光谱展宽的功率饱和效应 作者 李曙光;程同蕾;张焕平;侯蓝田; 单位 燕山大学理学院亚稳材料制备技术与科学国家重点实验室,燕山大学理学院亚稳材料制备技术与科学国家 重点实验室,晋中学院物理系,燕山大学理学院亚稳材料制备技术与科学国家重点实验室 河北秦皇岛 066004,河北 秦皇岛 066004,山西榆次 030600,河北秦皇岛 066004 中文摘要 利用自制的微结构光纤进行了飞秒激光脉冲传输实验,输入激光脉冲的中心波长为 800 nm,位于微结构 光纤的正常色散区。随着输入激光脉冲的平均功率从 220 mW 逐渐增大到 300 mW,输出光谱同时向长波和短波 方向展宽,光谱中的反斯托克斯线对应的能量逐渐占据主导地位。平均功率达到 280 mW 时,光谱的展宽范围不 再增大,显示出了一种功率饱和效应。在微结构光纤的正常色散区实现了波长从 560~960 nm 的 20 dB 展宽谱。 刊名 中国激光 年 2008 期 07 52 题名 飞秒激光切割神经细胞突起 作者 戴娟;周明;杨海峰;狄建科;赵恩兰; 单位 江苏大学光子制造科学中心,江苏大学光子制造科学中心,江苏大学光子制造科学中心,江苏大学光子制造科 学中心,江苏大学光子制造科学中心 江苏,镇江 212013,江苏,镇江 212013,江苏,镇江 212013,江苏,镇江 212013,江 苏,镇江 212013 中文摘要 利用飞秒激光脉冲在细胞内部的非线性吸收,产生等离子体,通过产生等离子体诱导蚀除效应,从而达到 细胞微手术的效果。对飞秒激光神经细胞突起切割的机理进行了初步分析,并研究了实验参量对切割作用和细胞 活性的影响,发现平均功率≥0.5mW 的飞秒激光经 40 倍物镜(NA=0.60)聚焦进细胞中会产生光致破裂现象,导致 作用细胞的死亡;稍低激光功率下在突起离胞体远近不同处切割,细胞均不会发生死亡,且稍远距离下切割细胞的 突起似对细胞影响不大;不完全切割突起情况下,切割长度较小时,对细胞影响不大。 刊名 激光与光电子学进展 年 2008 期 07 53 题名 飞秒强激光对二氧化钛金红石晶体相变的影响 作者 郭广磊;钟敏建;马宁华;叶果; 单位 上海大学理学院物理系,上海大学理学院物理系,上海大学理学院物理系,上海大学理学院物理系 上海 200444,上海 200444,上海大学分析测试中心,上海 200444,上海 200444,上海 200444 中文摘要 该文章报道了利用显微激光拉曼光谱仪研究近红外飞秒强激光脉冲诱导二氧化钛金红石单晶所引起的 相变.实验辐照时间为 60 s,当激光辐照平均功率增加时,锐钛矿相的拉曼振动模式强度增强,金红石相的拉曼振动 模式强度减弱.通过金红石相和锐钛矿相粉体等拉曼光谱的实验,肯定了随着辐照激光功率的增大,可以通过拉曼 最新文献报导 12 XIOPM latest Documents Report 光谱中锐钛矿 A1g+B1g(515 cm-1)振动模式标志峰和金红石相 Eg(445 cm-1)振动标志峰分别对应面积的比判断 其相变量. 刊名 原子与分子物理学报 年 2008 期 03 54 题名 光学晶体 K_2Al_2B_2O_7 相位匹配参量放大研究 作者 宋春荣;赵建君;刘进; 单位 军械工程学院基础部,军械工程学院基础部,军械工程学院基础部 河北石家庄 050003,河北石家庄 050003,河 北石家庄 050003 中文摘要 对 K2Al2B2O7(KABO)晶体的相位匹配飞秒激光参量放大(OPA)特性进行了系统的理论计算和分析。 分别讨论了Ⅰ型、Ⅱ型参量放大共线以及非共线情况,计算了在不同非共线夹角下的相位匹配角度。研究结果表 明:对于一定波长的抽运光,存在一定的非共线入射角对应一定波长的信号光。在 KABOⅠ型参变条件下,非共线 角的引入使相位匹配角增大。这对于高效率地产生脉宽极短的飞秒参量激光、扩大飞秒激光的调谐范围以及通 过参量技术放大飞秒脉冲都具有重要的意义。 刊名 军械工程学院学报 年 2008 期 03 55 题名 超短脉冲激光与介质相互作用过程中光学特性的变化 作者 王利;范滨;王占山;陈玲燕; 单位 同济大学精密光学工程技术研究所,株式会社光驰,同济大学精密光学工程技术研究所,同济大学精密光学工 程技术研究所 上海 200092,株式会社光驰,竹野 350-0801,竹野 350-0801,上海 200092,上海 200092 中文摘要 根据雪崩离化模型,分析了飞秒激光脉冲与介质材料相互作用过程中光学特性的变化规律。由于多层 膜光学元件的光学特性与材料的折射率密切相关,当飞秒激光照射介质材料时,折射率会随着电场强度分布呈现 不同程度的减小,从而会影响光学元件的性能。文中计算了飞秒激光照射多层膜光学元件时的透射光谱曲线,结 果表明薄膜材料在发生不可逆损伤之前,光学元件的光谱特性已经发生变化。 刊名 光学仪器 年 2008 期 03 56 题名 空气中激光等离子体通道的三次谐波光谱特性研究 作者 李海宁;张丽平;吴洪;李贤;丁良恩; 单位 华东师范大学光谱学与波谱学教育部重点实验室华东师范大学物理系,华东师范大学光谱学与波谱学教育 部重点实验室华东师范大学物理系,华东师范大学光谱学与波谱学教育部重点实验室华东师范大学物理系,华东 师范大学光谱学与波谱学教育部重点实验室华东师范大学物理系,华东师范大学光谱学与波谱学教育部重点实验 室华东师范大学物理系 上海 200062,上海 200062,上海 200062,上海 200062,上海 200062 中文摘要 对不同条件下强激光在空气中形成等离子体通道的三次谐波光谱特性进行了研究。单脉冲能量 12mJ, 脉宽 30 fs,重复频率 10 Hz,中心波长 795 nm 的飞秒激光脉冲经 0.5 m 焦距的凹面镜聚焦,在空气中形成了等离子 体通道,并在前向观测到谱线半峰全宽(FWHM)为 15 nm 的三次谐波。随着脉冲啁啾的变化,三次谐波的光谱出现 红移或兰移,当激光脉冲附带+1.3×105fs2 的二阶色散时,三次谐波谱线红移且谱峰强度增长了两倍。同时,通过 改变可编程声光色散滤波器(AOPDF)光谱调制的位置(Hole position),三次谐波的光谱也发生频移。 刊名 光谱学与光谱分析 年 2008 期 06 57 题名 飞秒激光泵浦-探测热反射系统的建立与调试 作者 祝捷;唐大伟;程光华;韩鹏;赵卫;张兴; 单位 中国科学院工程热物理研究所,中国科学院工程热物理研究所,中国科学院西安光学精密机械研究所瞬态光 学与光子技术国家重点实验室,中国科学院工程热物理研究所,中国科学院西安光学精密机械研究所瞬态光学与 光子技术国家重点实验室,清华大学航天航空学院 北京 100190;中国科学院研究生院,北京 100049,北京 100190,陕 西 西安 710119,北京 100190;中国科学院研究生院,北京 100049,陕西 西安 710119,北京 100084 最新文献报导 13 XIOPM latest Documents Report 中文摘要 建立了用来研究超快传热现象的飞秒激光泵浦-探测热反射系统。利用该系统测量并得到了在 140fs(飞秒)超短脉冲激光加热下,50nm 金膜的非平衡电子温升引起的反射信号随时间的变化曲线。由于加热光 单脉冲能量密度只有 5×10~(-3)mJ/cm~2,估算最高温升在 10K 以内,这有效地减小了由于物性参数随温度变化而 引起的误差。论文介绍了在系统的调试过程中,各种因素对实验结果的影响,并对实验结果及数据处理方法进行 了讨论。 刊名 工程热物理学报 年 2008 期 07 58 题名 飞秒激光微爆加工铌酸锂晶体 作者 肖诗洲;郭锐;程光华;黄文浩; 单位 中国科学技术大学精密机械与精密仪器系,中国科学技术大学精密机械与精密仪器系,中国科学院西安光学 机械精密机械研究所瞬态光学国家重点实验室,中国科学技术大学精密机械与精密仪器系 安徽合肥 230027,安徽 合肥 230027,陕西西安 710068,安徽合肥 230027 中文摘要 利用紧聚焦飞秒激光脉冲入射到铌酸锂(LiNbO3)晶体中引起微爆,可以在晶体内部进行微爆加工.与各 向同性的熔融石英不同,因为铌酸锂晶体的各向异性,微爆加工点在垂直晶轴的截面上表现出强烈的各向异性.我 们利用狭缝光阑对入射飞秒高斯光束进行整形,改变了光束的能量分布,成功地减小加工点的各向异性,获得尺寸 较一致的微爆单元.另外发现由于折射率失配的存在,飞秒脉冲激光聚焦深度不一样时,微爆加工点在沿晶轴方向 的截面形状和尺寸都有很大的变化,对此也进行了理论和实验上的分析. 刊名 中国科学技术大学学报 年 2008 期 05 成像光谱 59 题名 超光谱成像差分吸收光谱技术研究 作者 司福祺;谢品华;Klaus-Pet Hereue;刘诚;彭夫敏;刘文清; 单位 中国科学院环境光学与技术重点实验室中国科学院安徽光学精密机械研究所;环境物理研究所德国海德堡 大学;卫星研究小组马普化学所; 中文摘要 基于散射光的被动差分吸收(DOAS)技术利用气体的特性吸收谱线可实现对不同大气污染气体的定量 测量,介绍了一种基于成像光谱仪的光学遥感系统,该系统运用被动 DOAS 原理实现了对大气污染气体的二维成 像测量,并报道了该系统对实验室样品池一维测量与城市道路上方 NO2 组分的成像测量实验.基于成像光谱仪的 被动 DOAS 系统利用太阳散射光可获取垂直方向一维的光谱信息,结合扫描装置,便可实现对污染气体的二维成 像解析. 刊名 物理学报 年 2008 期 09 60 题名 显微超光谱成像仪用于大鼠糖尿病视网膜病变研究 作者 李庆利;薛永祺;张敬法;肖功海; 单位 华东师范大学信息学院,中国科学院上海技术物理研究所,上海交通大学医学院健康科学研究所,中国科学院 上海技术物理研究所 上海 200062,上海 200083,上海 200025,上海 200083 中文摘要 将超光谱成像技术与显微镜技术相结合,研制了推帚式显微超光谱成像仪.使用该设备采集了正常、糖 尿病和药物治疗大鼠的视网膜组织切片的显微超光谱图像数据.通过对正常对照组、糖尿病组、药物治疗组共 40 例样本的显微超光谱数据进行处理,获得了 3 组样本的单波段图像和三波段伪彩色合成图像,并提取了各组样 本外核丛的典型透射率光谱曲线.分析这些曲线发现,糖尿病大鼠视网膜外核丛组织细胞在 400~800nm 光谱范围 内的透射率整体高于正常大鼠,并且在第 180 波段附近出现一个小的吸收峰,注射 LCVS1001 药物治疗后大鼠视 网膜外核丛组织的透射率介于正常组与糖尿病组之间,且 180 波段附近的吸收峰变弱,因此该药物对大鼠糖网病 有一定的治疗作用.通过对 3 组样本的图像和光谱特征的分析表明,可以将显微超光谱成像仪作为一种新的手段, 辅助医学研究人员对糖网病的发病和致盲机制以及各种药物的治疗效果进行研究. 刊名 中国科学(C 辑:生命科学) 年 2008 最新文献报导 14 XIOPM latest Documents Report 期 08 61 题名 空间调制干涉光谱成像仪偏振度测试 作者 崔燕;计忠瑛;高静;白清兰;相里斌; 单位 中国科学院西安光学精密机械研究所,中国科学院西安光学精密机械研究所,中国科学院西安光学精密机械 研究所,中国科学院西安光学精密机械研究所,中国科学院西安光学精密机械研究所 西安 710119 中国科学院研究 生院,北京 100039,西安 710119,西安 710119 中国科学院研究生院,北京 100039,西安 710119,西安 710119 中文摘要 在计算分析的基础上,采用极值搜索法,利用太阳模拟器(波长范围:250mm~2500mm),准直镜(焦 距:120mm)和偏振片(消光比:1/500)对空间调制干涉光谱成像仪的偏振特性进行测试.结果表明:偏振片的消光比 以及准直镜自身的偏振度是影响空间调制干涉光谱成像仪偏振度测量过程中不确定度的主要因素. 刊名 光子学报 年 2008 期 06 62 题名 荧光光谱成像在生物芯片蛋白量化分析中的应用研究 作者 朝克夫;张友林;孔祥贵;李冰;曾庆辉;宋凯;孙雅娟; 单位 中国科学院长春光学精密机械与物理研究所激发态重点实验室,中国科学院长春光学精密机械与物理研究 所激发态重点实验室,中国科学院长春光学精密机械与物理研究所激发态重点实验室,中国科学院长春光学精密 机械与物理研究所激发态重点实验室,中国科学院长春光学精密机械与物理研究所激发态重点实验室,中国科学 院长春光学精密机械与物理研究所激发态重点实验室,中国科学院长春光学精密机械与物理研究所激发态重点实 验室 吉林长春 130033 中国科学院研究生院,北京 100039,吉林长春 130033,吉林长春 130033,吉林长春 130033,吉 林长春 130033,吉林长春 130033 中国科学院研究生院,北京 100039,吉林长春 130033 中文摘要 采用荧光光谱成像并结合椭圆偏振技术研究了 3-氨基 3-乙氧基硅烷(APTES)修饰及其与戊二醛 (APTES-Glu)共同修饰的两种不同表面上固定的羊抗人抗体活性和数量及其荧光免疫结合。研究结果表明:应用 荧光光谱成像在 APTES-Glu 表面上检测到的 FITC 标记人血清蛋白分子的数量为 APTES 表面结合的 2.8 倍,而 应用椭圆偏振技术在前者表面上检测到的 FITC 标记人血清蛋白分子的数量为后者表面上的 2.2 倍。这个结果说 明:在荧光免疫检测中,荧光光谱成像完全可用于分析不同表面固定蛋白的免疫活性和半定量的检测。 刊名 光谱学与光谱分析 年 2008 期 07 63 题名 基于地面多光谱成像技术的茄子灰霉病无损检测研究 作者 吴迪;朱登胜;何勇;张传清;冯雷; 单位 浙江大学生物系统工程与食品科学学院,金华职业技术学院,浙江大学生物系统工程与食品科学学院,浙江大 学农业与生物技术学院,浙江大学生物系统工程与食品科学学院 浙江杭州 310029,浙江金华 321017,浙江杭州 310029,浙江杭州 310029,浙江杭州 310029 中文摘要 实时、便捷、可靠的作物病害诊断方法是进行科学的作物喷药管理的基础,也是精细农作的关键技术 之一。根据感染灰霉病菌的茄子叶片的光谱反射特征和相应的特征波段的图像信息,利用基于地面的包含绿、 红、近红外三波段灰度图的多光谱成像技术对染病茄子叶片进行病斑的无损检测。目的是建立能准确反映植物 病害状况的检测模型,实时过滤掉土壤噪声、气候条件等环境干扰,实现对植物健康状况进行快速、准确、非破 坏性检测。结果显示,利用绿、红和近红外三通道图像信息算法模型,能够在有干燥的土壤和枯叶等干扰下对灰 霉病斑进行较好的识别,为植物生产中病害的在线无损检测提供了新的方法。 刊名 光谱学与光谱分析 年 2008 期 07 64 题名 相似异物的透/反射光谱成像检测新方法 作者 郏东耀;刘泽; 单位 北京交通大学电子信息工程学院先进控制系统研究所,北京交通大学电子信息工程学院先进控制系统研究 所 北京 100044,北京 100044 中文摘要 针对复杂背景中相似异物检测难题,提出了一种利用透/反射光谱成像的相似异物检测方法。该方法利 用异物与背景不同的透/反射特性差异,根据差异建立不同的成像模式,在不同的成像模式下优选最佳光照波长以 最新文献报导 15 XIOPM latest Documents Report 区分背景中的异物,以此构建透/反射光谱成像检测系统。以棉花中的白色丝状异物作为实验对象,利用最佳波长 透/反射成像系统获取异物图像特征,采用二值化自适应阈值图像处理从背景中提取异物。实验结果表明,在反射 光照系数 0.74 及透射光照系数 0.83 条件下,该方法对相似异物的检测率达到 91%。这一方法为目前相似异物检 测提供一条切实可行的新思路。 刊名 光电工程 年 2008 期 06 65 题名 基于 FPGA 的超光谱成像仪数据采集系统设计 作者 何海波;谢惜惜;王跃明;刘银年; 单位 中国科学院上海技术物理研究所,中国科学院上海技术物理研究所,中国科学院上海技术物理研究所,中国科 学院上海技术物理研究所 上海 200083,上海 200083,上海 200083,上海 200083 中文摘要 基于 FPGA 设计了一套数据采集系统,实现某超光谱成像仪研制过程中的光谱图像数据的采集、传 输、显示与存储。该设计综合应用了 FPGA、USB、LVDS、时钟数据恢复、8B/10B 编码、乒乓缓存等技术,具 有高速率、低功耗、小型化和轻量化等特点,对类似数据采集系统的设计具有参考和借鉴意义。 刊名 科学技术与工程 年 2008 期 12 66 题名 子宫颈组织的非线性光谱分辨成像 作者 罗天舒;陈建新;卓双木;邹起练; 单位 福建师范大学物理与光电信息科技学院,福建师范大学物理与光电信息科技学院,福建师范大学物理与光电 信息科技学院,福建医科大学细胞生物学与遗传学系 福建福州 350007,福建福州 350007,福建福州 350007,福建福 州 350004 中文摘要 本文是将基于双光子激发自体荧光和二次谐波信号成像的非线性光谱分辨成像技术用于上皮组织如子 宫颈组织进行研究,并采用背向探测模式,不仅获得子宫颈组织清晰的层结构图像,而且同时获得反映该组织生理 病理信息的各层光谱。实验证明这种技术能将双光子显微术和光谱测量技术的优点集于一身,能同时获得组织内 在成分的微结构和光谱特性,为生物组织生理和病理的临床早期无损诊断提供更全面更准确的方法,有望成为临 床活体无损诊断子宫颈癌的有效方法。 刊名 科技信息(科学教研) 年 2008 期 16 67 题名 干涉成像光谱仪切趾函数对复原光谱的影响分析 作者 张文娟;张兵;张霞;高连如;张维; 单位 中国科学院遥感应用研究所遥感科学国家重点实验室,中国科学院对地观测与数字地球科学中心,中国科学 院遥感应用研究所遥感科学国家重点实验室,中国科学院对地观测与数字地球科学中心,合肥工业大学理学院 北 京 100101,中国科学院研究生院,北京 100049,北京 100080,北京 100101,北京 100080,安徽合肥 230009 中文摘要 随着搭载干涉成像光谱仪 HJY20-1-A 的我国环境与减灾遥感卫星 HJ-1A 即将发射,我国干涉光谱成像 研究也从实验室开始走向实用化.在干涉光谱成像过程中,切趾函数处理是干涉成像光谱仪光谱复原过程中的一 个重要环节,对复原光谱的精度有着极其重要的影响.根据 HJY20-1-A 的参数设置,文中首先模拟了 24 种典型地 物对应于 HJY20-1-A 和其它最大光程差设置的干涉成像光谱仪数据,在不同切趾函数作用下的复原光谱,结果表 明 Hann ing 函数是其中最有效、最为稳定的切趾函数,同时发现切趾函数的应用虽然可以提高复原光谱的精度, 但与真实光谱仍存在一定差距,尤其对应 HJY20-1-A,复原光谱的精度更加有限.在以上分析基础上,提出了基于仪 器线型函数标准化的光谱复原改进算法,实验结果证实了该方法可以显著提高复原光谱精度,尤其适用于最大光 程差较小的空间调制型干涉成像光谱仪.最后,就 HJY20-1-A 复原光谱对 3 种典型植被指数求解,进一步证明了该 方法的有效性. 刊名 红外与毫米波学报 年 2008 期 03 68 题名 基于显微高光谱成像的人血细胞研究 最新文献报导 16 XIOPM latest Documents Report 作者 李庆利;肖功海;薛永祺;张敬法; 单位 华东师范大学信息科学技术学院,中国科学院上海技术物理研究所,中国科学院上海技术物理研究所,中国科 学院上海生命科学研究院健康科学中心 上海 200062,上海 200083,上海 200083,上海 200030 中文摘要 使用自行研制的推帚式显微高光谱成像系统采集了正常、白血病人血液涂片的显微高光谱图像数据。 通过对正常、白血病人血液显微高光谱数据进行处理,获得了人血液的单波段图像,并提取了部分血液细胞的典 型透射率光谱曲线。分析这些曲线发现,病变细胞透射率普遍高于正常细胞,特别是在 541.3nm 附近透射率高出 了 50%左右。通过对血液涂片的图像和光谱特征进行分析表明,经过一定的改进,可以将显微高光谱成像系统作 为一种新的检测手段,辅助医学研究人员对人血液进行分析。 刊名 光电工程 年 2008 期 05 69 题名 激光等离子体球面晶体光谱成像 作者 王洪建;肖沙里;施军;唐昶环;刘慎业;钱家渝; 单位 重庆大学光电技术及系统教育部重点实验室,重庆大学光电技术及系统教育部重点实验室,重庆大学光电技 术及系统教育部重点实验室,中国工程物理研究院激光聚变研究中心,中国工程物理研究院激光聚变研究中心,重 庆大学光电技术及系统教育部重点实验室 重庆 400044,重庆 400044,重庆 400044,四川绵阳 621900,四川绵阳 621900,重庆 400044 中文摘要 利用自聚焦原理,研制了一种新型的球面弯晶谱仪。晶体分析器采用云母材料,其弯曲半径为 380 mm, 布拉格角为 51°。利用成像板接收光谱信号,其有效面积为 30 mm×80 mm,从等离子体源经晶体到成像板的光 程长为 980 mm。物理实验在中国工程物理研究院激光聚变研究中心 20 J 激光装置上进行,入射激光能量为 6.78 J,成像板获得了铝激光等离子体 X 射线的光谱空间分辨信号。球面云母弯晶谱仪的光谱分辨率达到 1 000~1 500, 在相同环境放置的 PET 平晶的光谱分辨率为 50~100。结果表明:球面弯晶具有较高的光谱分辨率和信噪比,适合 于激光等离子体 X 射线的光谱学研究。 刊名 强激光与粒子束 年 2008 期 02 70 题名 傅里叶变换成像光谱数据压缩 作者 吕群波;袁艳;相里斌; 单位 中国科学院西安光学精密机械研究所,北京航空航天大学,中国科学院西安光学精密机械研究所 西安 710119 中国科学院研究生院,北京 100039,北京 100083,西安 710119 中文摘要 通过对傅里叶变换成像光谱仪数据的高低频反演光谱与光程差间的关系进行分析,提出一种光谱插值 预测与量化编码压缩方法.仿真结果表明,在相对光谱二次误差<1%的情况下,压缩比优于 5∶1. 刊名 光子学报 年 2008 期 03 71 题名 像元光敏宽度对干涉成像仪复原光谱幅值的影响 作者 吴娜;向阳; 单位 中国科学院长春光学精密机械与物理研究所,中国科学院长春光学精密机械与物理研究所 长春 130033 中国 科学院研究生院,北京 100039,长春 130033 中文摘要 推导出了静态干涉成像光谱仪的探测器阵列采样空间调制干涉图的实际数学表达式,由此进一步推导 出了含像元光敏宽度的复原光谱幅值的一般表达式。分析结果表明,当像元间距一定时,光敏宽度对复原光谱幅 值存在影响。对于确定的光敏宽度,随着波数的变长,复原光谱幅值所受到的影响逐渐增大;对于确定的波数,随着 光敏宽度的变宽,复原光谱幅值所受到的影响逐步增大。 刊名 光学技术 年 2008 期 02 72 题名 基于高光谱成像技术的中医舌象辅助诊断系统 作者 李庆利;薛永祺;刘治; 最新文献报导 17 XIOPM latest Documents Report 单位 华东师范大学信息科学技术学院,中国科学院上海技术物理研究所,上海交通大学电子信息与电气工程学院 上海 200062,上海 200083,上海 200030 中文摘要 中医舌诊是传统中医的一种重要诊断方法。由于舌诊是一种定性的、主观的和基于经验的诊断方法, 从而制约了中医舌诊在临床医学上的广泛应用。针对中医舌诊现代化中存在的问题,开发研制了一种基于高光谱 成像技术的舌象辅助诊断系统。这一系统包括高光谱舌图像采集、图像存储、特征提取和辅助诊断几部分。系 统使用高光谱成像技术代替通常使用的数码相机进行舌图像采集,并对高光谱舌图像进行了图像和光谱特征提取, 然后使用贝页斯分类器初步建立起了舌象特征与病症之间的联系,最后通过初步试验证明了这一系统的有效性。 刊名 生物医学工程学杂志 年 2008 期 02 73 题名 显微高光谱成像的生物组织定量检测机理及方法研究 作者 李庆利;薛永祺;肖功海;张敬法; 单位 华东师范大学信息科学技术学院极化材料和器件教育部重点实验室,中国科学院上海技术物理研究所,中国 科学院上海技术物理研究所,中国科学院生命科学研究院 上海交通大学医学院健康科学研究所,,上海 200241,上 海 200083,上海 200083,上海 200025 中文摘要 将显微镜技术与高光谱成像技术相结合,研制出了推帚式显微高光谱成像系统.介绍了系统原理和实现 的关键技术,并对系统的性能进行了分析.对显微高光谱数据的预处理方法进行了研究,提出了一种利用空白显微 高光谱图像进行光谱响应校正的算法.对校正后的数据进行了归一化处理,反演出了生物组织的透射率光谱曲线. 使用该系统采集了大鼠视网膜组织切片的显微高光谱数据,获得了视网膜切片的单波段图像和 3 波段伪彩色合成 图像,并提取出了透射率光谱曲线.初步试验表明,显微高光谱成像系统在生物样本的检测和分析中具有良好的应 用前景. 刊名 科学通报 年 2008 期 04 74 题名 基于多通道窄带滤波阵列的微型多光谱成像仪 作者 叶玉;张涛;郑伟波;王少伟; 单位 中国科学院上海技术物理研究所,中国科学院上海技术物理研究所,中国科学院上海技术物理研究所,中国科 学院上海技术物理研究所 上海 200083,上海 200083,上海 200083,上海 200083 中文摘要 设计出一种基于多通道窄带滤波阵列的微型多光谱成像仪。系统根据推帚式成像光谱仪的原理进行设 计,采用多通道窄带滤波阵列在后光学系统进行分光,利用高精度载物台驱动实验目标进行推扫成像,选用 USB 总 线作为数据采集的微机接口。整个系统由宽光谱光源、普通光学镜头、分光滤波片、面阵 CCD 成像装置、载 物台自动装置以及数据采集和控制模块等几部分组成。系统的光谱范围从 760nm 到 900nm,共 16 个波段,光谱分 辨率<10nm。系统具有同时获取不同波长光谱信息、结构紧凑、成本低、可靠性强和小型化等优点;不仅能够提 供目标在近红外的单波段光谱图像,而且能够获得图像中任意像素的光谱曲线,实现光谱技术和成像技术的结 合。 刊名 科学技术与工程 年 2008 期 08 75 题名 多角度成像光谱辐射仪在大气污染研究中的应用回顾 作者 刘阳;陈丹;Ralph A.Kahn;贺克斌; 单位 Harvard University School of Public Health,Boston,MA 02215,USA,清华大学环境科学与工程系,Jet Propulsion Laboratory/California Institute of Technology,Pasadena,CA 91109,USA,清华大学环境科学与工程系,,北京 100084,北 京 100084 中文摘要 美国宇航局于 1999 年底发射的多角度辐射成像光谱仪(MISR)采用了独特的多角度观测设计,将 9 台相 机沿卫星航迹方向按照固定角度排列并同时采集反射光.这种设计使其具备了当前其他星载气溶胶遥感设备不具 备的在陆地和海洋上空反演包括气溶胶浓度、形状以及组分的多种特性的能力.由于对细颗粒物非常敏感,MISR 为研究区域颗粒物空气质量的时空分布特性提供了新的数据来源.首先简要介绍 MISR 设备、它的气溶胶反演算 法及数据结构,然后综合论述了目前 MISR 气溶胶数据在空气质量研究方面的应用状况包括在污染事件(例如沙 尘、火灾以及城市空气污染)中对颗粒物空间分布的观测.MISR 高质量的气溶胶数据可以作为颗粒物浓度的定量 最新文献报导 18 XIOPM latest Documents Report 指标,回顾了目前在估算地面颗粒物浓度方面的研究成果,介绍了使用 MISR 高级数据对烟尘高度以及颗粒物成 份的研究.由于中分辨率成像光谱仪(MODIS)的气溶胶数据在中国有较广泛的使用,讨论中尽可能的与之进行了 比较.最后总结了 MISR 数据在空气质量研究中的优点与不足.相信 MISR 反演的丰富的高度定量化的气溶胶数据 对研究中国空气质量问题具有很大的应用价值. 刊名 中国科学(D 辑:地球科学) 年 2008 期 03 76 题名 基于 USB 的超光谱成像仪数据采集系统的设计 作者 何海波;谢惜惜;王跃明;刘银年; 单位 中国科学院上海技术物理研究所,中国科学院上海技术物理研究所,中国科学院上海技术物理研究所,中国科 学院上海技术物理研究所 上海 200083,上海 200083,上海 200083,上海 200083 中文摘要 设计了一套基于 USB 2.0 高速串行总线的数据采集系统,实现了某超光谱成像仪研制过程中的光谱图 像数据采集、传输、显示与存储。系统的软硬件设计综合应用了 USB、LVDS、时钟数据恢复、8B/10B 编码、 乒乓缓存、多线程和 DirectDraw 等技术.相对于传统的基于 ISA/PCI 总线的成像光谱仪数据采集系统,该设计支 持热插拔和总线供电,具有低功耗、小型化和轻量化等特点,对类似数据采集系统的设计具有参考和借鉴意义。 刊名 红外 年 2008 期 05 77 题名 基于液晶滤光器的连续光谱成像测试装置 作者 赵静;庞其昌;马骥;郑茜文;孟庆霞; 单位 暨南大学光电工程系,暨南大学光电工程系,南方医科大学中医药学院,暨南大学光电工程系,暨南大学光电工 程系 广州 510630 华南农业大学应用物理系,广州 510640,广州 510630,广州 510515,广州 510630,广州 510630 中文摘要 为了使普通光学采集设备同时获得样品光学形态和成份信息,设计了一种可以实现连续光谱成像的测 试装置.系统采用电可调液晶滤光器作为分光器件,低照度面阵 CCD 作为接收器,光谱分辨率可达到 0.5nm,无需传 统光谱成像仪中的机械推扫装置.在系统设计中,软件设计目的在于能够实现数据采集控制和后台数据处理等功 能.对系统的工作参量进行了测试,给出了系统透过率函数和线性工作范围.为了检测设备工作的稳定性,对低压汞 灯和氦氖激光器的光谱进行了检测,给出了多次测试结果的标准误差.最后对中药黄连的活性成份盐酸小檗碱进 行了在体检测,通过确定光谱特征,可得到其空间分布信息. 刊名 光子学报 年 2008 期 04 太阳能电池 78 题名 φ200mm 太阳能电池用直拉硅单晶生长中导流系统的研究 作者 任丙彦;褚世君;吴鑫;于建秀;孙秀菊; 单位 河北工业大学材料学院; 中文摘要 利用数值模拟,对 CZ 硅单晶生长系统中导流系统调整和改进,得到不同导流系统下的氩气流场和全局 温场.研究发现在导流系统中引入导流筒及冷却功能后,氩气流场得到明显的改善,晶体中纵向温度梯度均匀性改 善,固液界面趋于平坦,有利于结晶潜热的散发和单晶径向电阻率的均匀性.研究表明改进导流系统能提高结晶潜 热散发速率,有利于提高晶体拉速. 刊名 半导体学报 年 2008 期 09 79 题名 杜邦微电路材料事业部推出全新太阳能电池专用前板导电浆料 作者 单位 中文摘要 <正>杜邦公司电子科技部门旗下的杜邦微电路材料事业部(Microcircuit Materials)宣布,正式推出全新太 阳能电池专用的前板导电浆料(Front Side Silver Metallization Paste)DuPont 最新文献报导 19 XIOPM latest Documents Report 刊名 电子与电脑 年 2008 期 09 80 题名 提高薄膜太阳能电池的效率 作者 Izabela Kuzma;Guy Beaucarne ;Jef Poortmans; 单位 IMEC;IMEC; 中文摘要 <正>降低硅太阳能电池成本的方法之一是尽量减少高质量硅材料的使用量,如薄膜太阳能电池。不过 这种太阳能电池的效率只达到了约 11-12%。研究人员们正在寻求提升其效率的方法。最近取得突破的技术有 刊名 集成电路应用 年 2008 期 09 81 题名 InGaN 太阳能电池材料电学与光学性质的辐射研究 作者 董少光;范广涵; 单位 华南师范大学光电子材料与技术研究所; 中文摘要 研究表明,In1-xGaxN 合金材料的能隙能连续地从 0.7 eV 改变到 3.4 eV,使得该材料有可能成为太阳能 全光谱材料系.研究发现这些合金材料的电学特性表现出用高能质子(2 MeV)照射比当前常用的太阳能光伏材料 如 GaAs 和 GaInP 有更高的电阻,因此,给受到强辐射的太阳能电池提供了巨大的应用潜力.实验观察到这种材料 对辐照损伤具有不敏感的特征,该特征可用带边局域的平均振荡结合缺陷能给予解释.该缺陷能用 In1-xGaxN 合 金的 Fermi 能级的稳态能描述. 刊名 山东大学学报(工学版) 年 2008 期 04 82 题名 美研制出超薄太阳能电池发电成本接近煤电 作者 单位 中文摘要 <正>一种被科学家称为太阳能发电"革命"的太阳能电池,日前正在美国加州一家工厂大规模生产。这 种新式电池可象印刷报纸一样"印"在铝箔上,弹性好,重量轻。据研制生产电池板的硅谷纳米太阳能公司预计,用 这种电池板发电能象用煤发电一样便宜,其目标是生产出发电成本为 99 美分 1W 的电池板。该产品订单已经排 到了 2009 年。 刊名 能源与环境 年 2008 期 04 83 题名 钌配合物基太阳能电池光敏剂分子设计的最新研究进展 作者 凡素华;王科志; 单位 北京师范大学化学学院; 中文摘要 基于钌配合物染料的敏化太阳能电池与传统的硅半导体太阳能电池相比,具有较低的成本和较高的光 电转换效率(8%~11%)。本文重点从钌配合物染料分子中固定配体的选择、辅助配体中引进具有空穴传输功能 的三苯胺(或咔唑)基团以及配合物摩尔消光系数的提高 3 方面介绍近年钌配合物染料分子设计的研究进展。 刊名 无机化学学报 年 2008 期 08 84 题名 太阳能电池的研究进展与应用 作者 周传华;陈砺; 单位 华南理工大学化学与化工学院; 中文摘要 作为清洁可再生能源的太阳能,受到越来越多的研究,文中简单介绍了太阳能电池的发电机理和太阳能 电池材料的三个发展阶段,概述了中国太阳能发电技术产业现状及问题,展望了中国太阳能发电技术未来发展趋 势。 最新文献报导 20 XIOPM latest Documents Report 刊名 科协论坛(下半月) 年 2008 期 08 85 题名 不同二氧化钛电极制备方法对染料敏化太阳能电池性能的影响 作者 刘炜华;颜鲁婷;梁嘉;王鹏; 单位 广西大学物理科学与工程技术学院;北京交通大学理学院; 中文摘要 分别用溶胶凝胶法、电泳法以及溶胶凝胶与电泳复合法在导电玻璃上制备了二氧化钛薄膜。利用 SEM 及 XRD 对样品进行了表征。将所制得的薄膜用于染料敏化太阳能电池中,比较了 3 种方法所制得的电池的 输出性能。其中溶胶电泳复合法所制备的薄膜用于电池,开路电压达到 0.7V,短路电流达到 12.59mA/cm2,填充因 子达到 0.55,效率达到 3.14%,远远高于其他两种方法所制得的电池效率。 刊名 液晶与显示 年 2008 期 04 86 题名 塑料太阳能电池的研究现状与进展 作者 邓姝皓;刘丹;王之顺;熊依林;李洪飞; 单位 中南大学材料科学与工程学院; 中文摘要 塑料太阳能电池是一个新的研究领域,本文综述了塑料太阳能电池的工作原理、结构以及太阳能电池 材料(导电聚合物)的制备,着重就 n 型导电聚合物材料的制备及影响塑料太阳能电池光电转换效率等几个主要方 面进行了讨论,并对该电池的优势和在该领域的未来发展趋势做了展望。 刊名 材料开发与应用 年 2008 期 04 87 题名 新型太阳能电池板的研究 作者 郑宗慧;崔琦;黄玲;咸峥毅; 单位 上海应用技术学院机械与自动化工程学院; 中文摘要 传统的太阳能电池主要有硅系能电池和化合物薄膜电池。二氧化钛(锐钛矿型二氧化钛),作为一种新的 光催化剂,以其特有的功能,备受青睐。通过实验研究该类太阳能电池在各种条件下的工作状态与发电效率,使其 能最大程度的利用太阳能源,以缓解人类对于传统能源的过度开发,具有很大的社会价值和使用性。 刊名 上海应用技术学院学报(自然科学版) 年 2008 期 02 88 题名 基于太阳能电池板的直流不间断电源设计 作者 范长城;王勇;檀涌; 单位 四川大学电子信息学院; 中文摘要 为使控制电路在太阳能电池板掉电后仍能正常工作,有必要设计一种通用可行的不间断直流供电单 元。本文介绍一种基于 UC3906 的太阳能控制电路,此电路不仅可以高效可靠地控制充电,还能完成备用铅酸蓄 电池的投入与切断,实现不间断供电。 刊名 电源世界 年 2008 期 08 89 题名 适合教学的高性能太阳能电池测试系统 作者 曾令驰;潘涛;曾祥斌; 单位 华中科技大学附属高级中学;华中科技大学电子科学与技术系;华中科技大学电子科学与技术系; 中文摘要 利用短弧氙灯模拟 AM1.5 太阳光,通过数据采集模块采集初始电流、电压、温度、光谱响应参数,经 Lab-VIEW 和 Matlab 运算修正复现后,得到标准条件下的 I-V 特性曲线.该系统具有很高的精确度、自动化程度和 可靠性的同时,还具有灵活的测试范围,适用于实验教学. 刊名 物理实验 最新文献报导 21 XIOPM latest Documents Report 年 2008 期 08 90 题名 染料敏化太阳能电池 TiO_2 薄膜的制备方法 作者 高建华;钱伟君;吴伟;曾毅; 单位 中国科学院上海硅酸盐研究所;中国科学院上海硅酸盐研究所;中国科学院上海硅酸盐研究所;中国科学院上 海硅酸盐研究所; 中文摘要 阐述了对应用在染料敏化太阳能电池中作为电极的 TiO2 薄膜的要求,对如何能制备出具有较好电池性 能的 TiO2 薄膜电极的方法进行了综述,分析了各种方法的优劣,对未来染料敏化太阳能电池中 TiO2 薄膜的制备 方法提出了建议。 刊名 理化检验(物理分册) 年 2008 期 08 91 题名 基于光伏电池模拟器的最大功率点跟踪控制研究 作者 田立坤;张千帆;程树康; 单位 哈尔滨工业大学电气工程系,哈尔滨工业大学电气工程系,哈尔滨工业大学电气工程系 哈尔滨 150001,哈尔 滨 150001,哈尔滨 150001 中文摘要 不论光照强度及环境温度如何变化,最大功率点跟踪控制都可以使光伏电池输出最大功率。由于照 度、环境温度等条件不可控,变化周期长,在光伏阵列发电系统中研究最大功率点跟踪控制有众多不便。提出一 种光伏电池模拟器,在实验室内可以模拟光伏电池特性,改变照度等外界条件。分析了在 DC-DC 变换器中控制占 空比实现最大功率点跟踪控制的方法,在基于光伏电池模拟器构建的实验系统中实现了不同照度下的最大功率点 跟踪控制。 刊名 微电机 年 2008 期 07 Femtosecond and Attosecond Pulse 92 Author(s): Turchinovich, D (Turchinovich, Dmitry); Liu, XM (Liu, Xiaomin); Laegsgaard, J (Laegsgaard, Jesper) Title: Monolithic all-PM femtosecond Yb-fiber laser stabilized with a narrow-band fiber Bragg grating and pulse-compressed in a hollow-core photonic crystal fiber Source: OPTICS EXPRESS, 16 (18): 14004-14014 SEP 1 2008 Abstract: We report on an environmentally stable self-starting monolithic (i.e. without any free-space coupling) all-polarizationmaintaining (PM) femtosecond Yb-fiber laser, stabilized against Q-switching by a narrow-band fiber Bragg grating and modelocked using a semiconductor saturable absorber mirror. The laser output is compressed in a spliced-on hollowcore PM photonic crystal fiber, thus providing direct end-of-the-fiber delivery of pulses of around 370 fs duration and 4 nJ energy with high mode quality. Tuning the pump power of the end amplifier of the laser allows for the control of output pulse bandwidth and duration. Our experimental results are in good agreement with the theoretical predictions. -------------------------------------------------------------------------------93 Author(s): Zhang, HB (Zhang, Haibin); Ho, S (Ho, Stephen); Eaton, SM (Eaton, Shane M.); Li, JZ (Li, Jianzhao); Herman, PR (Herman, Peter R.) Title: Three-dimensional optical sensing network written in fused silica glass with femtosecond laser Source: OPTICS EXPRESS, 16 (18): 14015-14023 SEP 1 2008 Abstract: A single-step fast-writing method of burst ultrafast laser modification was applied to form a mesh network of multiwavelength Bragg grating waveguides in bulk fused silica glass. Strain-optic and thermo-optic responses of the laserwritten internal sensors are reported for the first time. A dual planar layout provided independent temperature- and strain-compensated characterization of temperature and strain distribution with coarse spatial resolution. The grating responses were thermally stable to 500 degrees C. To our best knowledge, the grating network represents the first demonstration of 3D distributed optical sensing network in a bulk transparent medium. Such 3D grating networks open 最新文献报导 22 XIOPM latest Documents Report new directions for strain and temperature sensing in optical circuits, optofluidic, MEMS or lab-on-a-chip microsystems, actuators, and windows and other large display or civil structures. (C) 2008 Optical Society of America. -------------------------------------------------------------------------------94 Author(s): Zhang, SG (Zhang, Shuanggen); Yao, JH (Yao, Jianghong); Liu, WW (Liu, Weiwei); Huang, ZC (Huang, Zhangchao); Wang, J (Wang, Jue); Li, YN (Li, Yongnan); Tu, CH (Tu, Chenghou); Lu, FY (Lu, Fuyun) Title: Second harmonic generation of periodically poled potassium titanyl phosphate waveguide using femtosecond laser pulses Source: OPTICS EXPRESS, 16 (18): 14180-14185 SEP 1 2008 Abstract: The authors have presented in this paper the fabrication and characterization of double line written type waveguides in c-cut periodically poled potassium titanyl phosphate crystals. The waveguides were fabricated by using a femtosecond laser, and were utilized for second harmonic generation at 1064 nm. Our experiments have shown that single mode propagation was observed at optimal waveguide width of 14.5 mu m. And a conversion efficiency of 39.6% can be achieved. (C) 2008 Optical Society of America. -------------------------------------------------------------------------------95 Author(s): Aslund, ML (Aslund, Mattias L.); Jovanovic, N (Jovanovic, Nemanja); Groothoff, N (Groothoff, Nathaniel); Canning, J (Canning, John); Marshall, GD (Marshall, Graham D.); Jackson, SD (Jackson, Stuart D.); Fuerbach, A (Fuerbach, Alexander); Withford, MJ (Withford, Michael J.) Title: Optical loss mechanisms in femtosecond laser-written point-by-point fibre Bragg gratings Source: OPTICS EXPRESS, 16 (18): 14248-14254 SEP 1 2008 Abstract: yFibre Bragg gratings inscribed with the point-by-point method using a Ti-sapphire femtosecond laser operating at 800 nm are shown to display strong increasing attenuation towards shorter wavelengths with a large and spectrally sharp recovery observed below 400 nm. The origin of this loss is shown to be Mie scattering, and the sharp recovery in the transmission results from wavelength dependent scattering within the numerical aperture of the core. The permanent losses from these Type II gratings have implications for high temperature sensors and fibre lasers. (c) 2008 Optical Society of America. -------------------------------------------------------------------------------96 Author(s): Bulgakova, NM (Bulgakova, Nadezhda M.); Bulgakov, AV (Bulgakov, Alexander V.) Title: Comment on "Time-Resolved Shadowgraphs of Material Ejection in Intense Femtosecond Laser Ablation of Aluminum" - art. no. 099701 Source: PHYSICAL REVIEW LETTERS, 101 (9): 9701-9701 AUG 29 2008 -------------------------------------------------------------------------------97 Author(s): Zhang, N (Zhang, Nan); Zhu, XN (Zhu, Xiaonong) Title: Comment on "Time-Resolved Shadowgraphs of Material Ejection in Intense Femtosecond Laser Ablation of Aluminum" - Reply - art. no. 099702 Source: PHYSICAL REVIEW LETTERS, 101 (9): 9702-9702 AUG 29 2008 -------------------------------------------------------------------------------98 Author(s): Wang, BB (Wang, Bingbing); Chen, J (Chen, J.); Liu, J (Liu, Jie); Yan, ZC (Yan, Zong-Chao); Fu, PM (Fu, Panming) Title: Attosecond-pulse-controlled high-order harmonic generation in ultrashort laser fields - art. no. 023413 Source: PHYSICAL REVIEW A, 78 (2): 3413-3413 Part B AUG 2008 Abstract: By solving the three-dimensional time-dependent Schrodinger equation, we study how to control the high-order harmonic generation (HHG) in a hydrogenlike neon, which is exposed to an extreme-ultraviolet (xuv) attosecond laser pulse followed by an infrared (ir) femtosecond pulse. The xuv pulse prepares the atom as a superposition of the ground state, the excited states, and the continuum. These three types of states provide different contributions to the high-order harmonics generated by the following it pulse. In particular, the contributions from the excited states and the continuum extend the cutoff frequency of the harmonic spectrum. Moreover, the effect of the carrier-envelope phase of the it pulse on the HHG has been studied. The structure of the laser-dressed atom can be imaged using this two-color scheme. -------------------------------------------------------------------------------99 Author(s): Lee, JH (Lee, Jae-hwan); Lee, YS (Lee, Yong Soo); Park, J (Park, Juyun); Yu, TJ (Yu, Tae Jun); Nam, CH (Nam, Chang Hee) 最新文献报导 23 XIOPM latest Documents Report Title: Long-term carrier-envelope-phase stabilization of a femtosecond laser by the direct locking method Source: OPTICS EXPRESS, 16 (17): 12624-12631 AUG 18 2008 Abstract: We have developed a practical solution to implement the direct locking method for the carrier-envelope phase (CEP) stabilization of femtosecond laser pulses and achieved 24-hour CEP stabilization without realignment of any optical components. The direct locking method realizes the CEP stabilization in the time domain by directly quenching the beat signal from an f-to-2f interferometer and, thereby, locking every pulse to a same CEP. We have accomplished the longterm CEP stabilization using commercially available standard feedback electronics, and maintained the CEP stabilization with low jitter without using any frequency-analyzing components, greatly facilitating the accessibility of the CEP stabilization. (c) 2008 Optical Society of America. -------------------------------------------------------------------------------100 Author(s): Niioka, H (Niioka, H.); Smith, NI (Smith, N. I.); Fujita, K (Fujita, K.); Inouye, Y (Inouye, Y.); Kawata, S (Kawata, S.) Title: Femtosecond laser nano-ablation in fixed and non-fixed cultured cells Source: OPTICS EXPRESS, 16 (19): 14476-14495 SEP 15 2008 Abstract: To understand the onset and morphology of femtosecond laser submicron ablation in cells and to study physical evidence of intracellular laser irradiation, we used transmission electron microscopy (TEM). The use of partial fixation before laser irradiation provides for clear images of sub-micron intracellular laser ablation, and we observed clear evidence of bubble-type physical changes induced by femtosecond laser irradiation at pulse energies as low as 0.48 nJ in the nucleus and cytoplasm. By taking ultrathin sliced sections, we reconstructed the laser affected subcellular region, and found it to be comparable to the point spread function of the laser irradiation. Laser-induced bubbles were observed to be confined by the surrounding intracellular structure, and bubbles were only observed with the use of partial prefixation. Without partial pre-fixation, laser irradiation of the nucleus was found to produce observable aggregation of nanoscale electron dense material, while irradiation of cytosolic regions produced swollen mitochondria but residual local physical effects were not observed. This was attributed to the rapid collapse of bubbles and/or the diffusion of any observable physical effects from the irradiation site following the laser exposure. (c) 2008 Optical Society of America. -------------------------------------------------------------------------------101 Author(s): Prawiharjo, J (Prawiharjo, Jerry); Daga, NK (Daga, Nikita K.); Geng, R (Geng, Rui); Price, JHV (Price, Jonathan H. V.); Hanna, DC (Hanna, David C.); Richardson, DJ (Richardson, David J.); Shepherd, DP (Shepherd, David P.) Title: High fidelity femtosecond pulses from an ultrafast fiber laser system via adaptive amplitude and phase pre-shaping Source: OPTICS EXPRESS, 16 (19): 15074-15089 SEP 15 2008 Abstract: The generation of high-fidelity femtosecond pulses is experimentally demonstrated in a fiber based chirped-pulse amplification (CPA) system through an adaptive amplitude and phase pre-shaping technique. A pulse shaper, based on a dual-layer liquid crystal spatial light modulator (LC-SLM), was implemented in the fiber CPA system for amplitude and phase shaping prior to amplification. The LC-SLM was controlled using a differential evolution algorithm, to maximize a two-photon absorption detector signal from the compressed fiber CPA output pulses. It is shown that this approach compensates for both accumulated phase from material dispersion and nonlinear phase modulation. A train of pulses was produced with an average power of 12.6W at a 50MHz repetition rate from our fiber CPA system, which were compressible to high fidelity pulses with a duration of 170 fs. (C) 2008 Optical Society of America. -------------------------------------------------------------------------------102 Author(s): Fernandez, TT (Fernandez, T. Toney); Della Valle, G (Della Valle, G.); Osellame, R (Osellame, R.); Jose, G (Jose, G.); Chiodo, N (Chiodo, N.); Jha, A (Jha, A.); Laporta, P (Laporta, P.) Title: Active waveguides written by femtosecond laser irradiation in an erbium-doped phospho-tellurite glass Source: OPTICS EXPRESS, 16 (19): 15198-15205 SEP 15 2008 Abstract: We report on fs-laser micromachining of active waveguides in a new erbium-doped phospho-tellurite glass by means of a compact cavity-dumped Yb-based writing system. The spectroscopic properties of the glass were investigated, and the fs-laser written waveguides were characterized in terms of passive as well as active performance. In particular, internal gain was demonstrated in the whole C+L band of optical communications (15301610 nm). (C) 2008 Optical Society of America. -------------------------------------------------------------------------------103 最新文献报导 24 XIOPM latest Documents Report Author(s): An, R (An, Ran); Hoffman, MD (Hoffman, Michelle D.); Donoghue, MA (Donoghue, Margaret A.); Hunt, AJ (Hunt, Alan J.); Jacobson, SC (Jacobson, Stephen C.) Title: Water-assisted femtosecond laser machining of electrospray nozzles on glass microfluidic devices Source: OPTICS EXPRESS, 16 (19): 15206-15211 SEP 15 2008 Abstract: Using water-assisted femtosecond laser machining, we fabricated electrospray nozzles on glass coverslips and on assembled microfluidic devices. Machining the nozzles after device assembly facilitated alignment of the nozzles over the microchannels. The basic nozzle design is a through-hole in the coverslip to pass liquids and a trough machined around the through-hole to confine the electrospray and prevent liquid from wicking across the glass surface. Electrospray from the nozzles was stable with and without pressure-driven flow applied and was evaluated using mass spectra of the peptide bradykinin. (C) 2008 Optical Society of America. -------------------------------------------------------------------------------104 Author(s): Pacebutas, V (Pacebutas, V.); Biciunas, A (Biciunas, A.); Bertulis, K (Bertulis, K.); Krotkus, A (Krotkus, A.) Title: Optoelectronic terahertz radiation system based on femtosecond 1 mu m laser pulses and GaBiAs detector Source: ELECTRONICS LETTERS, 44 (19): 1154-U20 SEP 11 2008 Abstract: A terahertz time-domain spectroscopy system based on a femtosecond Yb:KGW laser, a narrow-gap semiconductor surface emitter, and a photoconductive detector made from an Si-doped GaBiAs epitaxial layer is demonstrated. The spectral bandwidth of the system is larger than 4 THz, and its dynamical range exceeds 60 dB. -------------------------------------------------------------------------------105 Author(s): Lee, GJ (Lee, G. J.); Lee, YP (Lee, Y. -P.); Jung, SG (Jung, S. G.); Hwangbo, CK (Hwangbo, C. K.); Kim, SS (Kim, S. S.); Cheong, H (Cheong, H.); Yoon, CS (Yoon, C. S.) Title: Photo-structuring of silver-oxide films by using femtosecond laser pulses Source: JOURNAL OF THE KOREAN PHYSICAL SOCIETY, 53 (3): 1414-1418 Part 1 Sp. Iss. SI SEP 2008 Abstract: We investigated the photo-structuring of silver-oxide films by using femtosecond laser pulses. The silver-oxide films were prepared by magnetron sputtering. The physical properties of the prepared silver-oxide films were investigated by using absorption spectroscopy. For the sample that underwent the photo-structuring of the silver-oxide films by two interfering femtosecond laser pulses, scanning and transmission electron microscopy measurements showed that a metal grating was formed through the photoreduction of silver oxide. Micro-photoluminescence spectroscopy showed spationally selective photoluminescence from the laser-modified region. In order to find the nature of laser-modified region, we compared the metal grating formed by laser interference structuring with the thermally annealed film. -------------------------------------------------------------------------------106 Author(s): Pfeifer, T (Pfeifer, Thomas); Abel, MJ (Abel, Mark J.); Nagel, PM (Nagel, Phillip M.); Jullien, A (Jullien, Aurelie); Loh, ZH (Loh, Zhi-Heng); Bell, MJ (Bell, M. Justine); Neumark, DM (Neumark, Daniel M.); Leone, SR (Leone, Stephen R.) Title: Time-resolved spectroscopy of attosecond quantum dynamics Source: CHEMICAL PHYSICS LETTERS, 463 (1-3): 11-24 SEP 22 2008 Abstract: The advent of attosecond pulsed radiation leads to a large unexplored scientific area in chemical physics: the direct time-resolved measurement of electronic quantum dynamics. Major scientific goals include spectroscopy of single- and multi-electron motion and dynamical electron correlations, relating to orbital interactions in valence and core electronic levels of atoms and molecules. The results of such studies address a wide array of scientific and technological applications. Here, the current state-of-the-art of attosecond-dynamics measurements is reviewed and several novel spectroscopic methods are discussed that are particularly important for applications in chemical physics: attosecond transient absorption/dispersion spectroscopy, laser-induced-dipole spectroscopy, and absolute-phase spectroscopy. (c) 2008 Elsevier B.V. All rights reserved. -------------------------------------------------------------------------------107 Author(s): Hong, WY (Hong Wei-Yi); Yang, ZY (Yang Zhen-Yu); Lan, PF (Lan Peng-Fei); Lu, PX (Lu PeiXiang) Title: Direct generation of isolated sub-50 attosecond pulse via controlling quantum paths by a low frequency field Source: ACTA PHYSICA SINICA, 57 (9): 5853-5858 SEP 2008 Abstract: 最新文献报导 25 XIOPM latest Documents Report We propose a new method to directly generate an isolated sub-50 attosecond pulse. The combination of a 5 fs driving laser pulse with the wavelength of 800 nm and a low frequency field with the wavelength of 10 mu m is adopted. The intensity of the low frequency field is 10% that of the driving pulse. It is shown that the harmonic spectrum is extended to I-P + 8.2 UPP and the harmonies above I-P + 4.2 U-P become continuous. By adjusting the phase of the carrierenvelope of the few-cycle pulse, the bandwidth of the supercontinuum can be further broadened and a close-to-Fourierlimit sub-50 as pulse is directly obtained. -------------------------------------------------------------------------------108 Author(s): Bartels, A (Bartels, A.); Heinecke, D (Heinecke, D.); Diddams, SA (Diddams, S. A.) Title: Passively mode-locked 10 GHz femtosecond Ti : sapphire laser Source: OPTICS LETTERS, 33 (16): 1905-1907 AUG 15 2008 Abstract: We report a mode-locked Ti:sapphire femtosecond laser emitting 42 fs pulses at a 10 GHz repetition rate. When operated with a spectrally integrated average power greater than 1 W, the associated femtosecond laser frequency comb contains similar to 500 modes, each with power exceeding 1 mW. Spectral broadening in nonlinear microstructured fiber yields comb elements with individual powers greater than 1 nW over similar to 250 nm of spectral bandwidth. The modes of the emitted comb are resolved and imaged with a simple grating spectrometer and digital camera. Combined with absorption spectroscopy of rubidium vapor, this approach permits identification of the mode index and measurement of the carrier envelope offset frequency of the comb. (C) 2008 Optical Society of America. -------------------------------------------------------------------------------109 Author(s): Dong-Qing, Y (Dong-Qing, Y.); Ming, Z (Ming, Z.); Lan, C (Lan, C.) Title: Femtosecond laser micromachining of an Au/Cr film nanostack Source: LASER PHYSICS, 18 (9): 1092-1097 SEP 2008 Abstract: Selective laser patterning of thin films in a multilayer structure is an emerging technology for the fabrication of MEMS devices. A 775-nm Ti:sapphire laser (130 fs, 1 kHz) was used to irradiate thin-film stacks with variations in the process parameters, such as the pulse energy, feed rate, and numerical aperture of the objective lens. The two layers of the Au/Cr film have the same thickness, which is about 1000 nm. They were coated on a glass substrate. By SEM, an AFM and an optical surface profiler, we investigate the morphology of a pattern including the line width, groove depth, and laser-induced periodic surface structures (LIPSSs). The ablation depth was observed to depend on the pulse energy. In addition, from the energy spectrum, we find which layer was removed completely. The experimental results show that precise micromachining with a desired stability and reproducibility can be achieved by controlling the ablation energy and the feed rate. With a different energy and feed rate, we have processed the gating and the circle, which with the smooth cutting edge and groove was consistent with the beam spatial distribution. -------------------------------------------------------------------------------- High-Power Laser and Solid-State Laser 110 Author(s): Liu, GY (Liu, George Y.); Mariampillai, A (Mariampillai, Adrian); Standish, BA (Standish, Beau A.); Munce, NR (Munce, Nigel R.); Gu, XJ (Gu, Xijia); Vitkin, IA (Vitkin, I. Alex) Title: High power wavelength linearly swept mode locked fiber laser for OCT imaging Source: OPTICS EXPRESS, 16 (18): 14095-14105 SEP 1 2008 Abstract: We report a long coherence length, high power, and wide tuning range wavelength linearly swept fiber mode-locked laser based on polygon scanning filters. An output power of 52.6 mW with 112 nm wavelength tuning range at 62.6 kHz sweeping rate has been achieved. The coherence length is long enough to enable imaging over 8.1 mm depth when the sensitivity decreases by 8.7 dB (1/e(2)). The Fourier components are still distinguishable when the ranging depth exceeds 15 mm, which corresponds to 30 mm optical path difference in air. The parameters that are critical to OCT imaging quality such as polygon filter linewidth, the laser coherence length, output power, axial resolution and the Fourier sensitivity have been investigated theoretically and experimentally. Since the wavelength is swept linearly with time, an analytical approach has been developed for transforming the interference signal from equidistant spacing in wavelength to equidistant spacing in frequency. Axial resolution of 7.9 mu m in air has been achieved experimentally that approaches the theoretical limit. (C) 2005 Optical Society of America. -------------------------------------------------------------------------------111 最新文献报导 26 XIOPM latest Documents Report Author(s): Torrisi, L (Torrisi, L.); Margarone, D (Margarone, D.); Laska, L (Laska, L.); Krasa, J (Krasa, J.); Velyhan, A (Velyhan, A.); Pfeifer, M (Pfeifer, M.); Ullschmied, J (Ullschmied, J.); Ryc, L (Ryc, L.) Title: Self-focusing effect in Au-target induced by high power pulsed laser at PALS Source: LASER AND PARTICLE BEAMS, 26 (3): 379-387 SEP 2008 Abstract: Self-focusing effects, induced by ASTERIX pulsed laser at PALS Laboratory of Prague, have been investigated. Laser was employed at the third harmonics (438 nm) and intensities of the order of 10(16) W/cm(2). Pure Au was used as thin target and irradiated with 30 degrees incidence angle. An ion energy analyzer was employed to detect the energy-tomass ratio of emitted ions front plasma. Measurements were performed by changing the focal point position with a high spatial resolution step-motor. Results demonstrated that non linear processes, due to self-focusing effects, occurs when the laser bean is focused at about 200 mu m in front of the target surface. In Such conditions, I new ion group, having hit,h charge state and kinetic energy is produced because of the increment in temperature of the laser-generated plasma. -------------------------------------------------------------------------------112 Author(s): Fan, RW (Fan Rong-Wei); Xia, YQ (Xia Yuan-Qin); Li, XH (Li Xiao-Hui); Jiang, YG (Jiang YuGang); Chen, DY (Chen De-Ying) Title: Investigation of broadband solid state dye laser based on PM580 doped PMMA Source: ACTA PHYSICA SINICA, 57 (9): 5705-5708 SEP 2008 Abstract: As solid-state dye lasers exhibit the attractive features of compactness, being intoxic, and low cost, the development of tunable solid-state dye lasers is an area of active research. Solid state dyes based on polymethyl methacylate (PMMA) doped with new high efficiency pyrromethene-580 were prepared. First, the absorption and fluorescence of the samples were obtained. Pumped by the second harmonic of Q switched Nd: YAG laser, the output characteristics of the solid state dye lasers with different dye concentrations were studied. The central wavelength of the lasing emission peak increases with increasing dye concentration. The slope efficiencies of the samples were also obtained. The highest slope efficiency of 53.8% was obtained with dye concentration of about 2 x 10(-4) mol/L. Pumped at 410 mJ, the pulse energy of the solid dye laser reached 220 mJ with the band width similar to 8 nm. -------------------------------------------------------------------------------113 Author(s): Ding, L (Ding Li); Liu, DZ (Liu Dai-Zhong); Gao, YQ (Gao Yan-Qi); Zhu, BQ (Zhu Bao-Qiang); Zhu, J (Zhu Jian); Peng, ZY (Peng Zeng-Yun); Zhu, JQ (Zhu Jian-Qiang); Yu, LJ (Yu Li-Jun) Title: New far-field detection technique for beam alignment system in high power laser facility Source: ACTA PHYSICA SINICA, 57 (9): 5713-5717 SEP 2008 Abstract: The laser beam automatic alignment system is applied to a high power laser facility for inertial confinement fusion. The far-field detection is a key technique of the automatic alignment system. Utilizing the image of spatial filter's pinhole of the high power laser system and diffraction of sampling grating, a new method for far-field detection of laser beam is proposed and fully demonstrated on the experimental system. The experimental results indicate that, unlike the traditional method, this far-field detection system can fully use the space through off-axial grating sampling, and the average far-field alignment error is less than 0.9% of spatial filter pinhole diameter, which meets the alignment system requirements of less than 5% of spatial filter pinhole diameter. -------------------------------------------------------------------------------114 Author(s): Kamath, MP (Kamath, M. P.); Tripathi, PK (Tripathi, P. K.); Kulkarni, AP (Kulkarni, A. P.); Chandra, R (Chandra, R.); Joshi, AS (Joshi, A. S.); Navathe, CP (Navathe, C. P.); Gupta, PD (Gupta, P. D.) Title: Design, development and performance characteristics of a large aperture disc amplifier for high power Nd: Glass laser chain Source: SADHANA-ACADEMY PROCEEDINGS IN ENGINEERING SCIENCES, 33 (4): 443-453 AUG 2008 Abstract: A large aperture disc amplifier has been designed, set-up and characterized for its performance on small signal gain, spatial variation of gain, and thermal recovery time. This amplifier, consisting of three elliptical Nd: phosphate glass discs of size 214 x 114 x 20 mm mounted at Brewster angle and pumped by ten xenon filled flash lamps of 600 mm arc length, provided a small signal gain of 6 at electrical pump energy of 36 kJ (in a pulse of 450 mu s) using an in-house developed dual-polarity capacitor bank based power supply. It was coupled to a high power Nd: phosphate glass laser chain and a maximum output pulse energy exceeding 100 J in a 1.5 ns (FWHM) pulse has been measured. A dry nitrogen gas based cooling system was developed for cooling the glass discs with a thermal recovery time of similar to 20 minutes. -------------------------------------------------------------------------------115 最新文献报导 27 XIOPM latest Documents Report Author(s): Kuna, L (Kuna, L.); Sommer, C (Sommer, C.); Zinterl, E (Zinterl, E.); Krenn, JR (Krenn, J. R.); Pachler, P (Pachler, P.); Hartmann, P (Hartmann, P.); Tasch, S (Tasch, S.); Leising, G (Leising, G.); Wenzl, FP (Wenzl, F. P.) Title: Volume structuring of high power LED encapsulates by femtosecond laser direct writing Source: APPLIED PHYSICS A-MATERIALS SCIENCE & PROCESSING, 93 (2): 421-427 NOV 2008 Abstract: We report on the micro-fabrication of diffractive optical elements (DOEs) such as 1D, 2D and concentric grating structures inside the volume of thin silicone films by femtosecond laser direct writing. In addition, we show that such structures can also be integrated into silicone films that act as encapsulation layers of high power light-emitting diodes. The latter strategy opens new possibilities to homogenize and to control the light emitted from such devices. -------------------------------------------------------------------------------116 Author(s): Lee, SN (Lee, Sung-Nam); Son, JK (Son, J. K.); Paek, HS (Paek, H. S.); Sung, YJ (Sung, Y. J.); Kim, KS (Kim, K. S.); Kim, HK (Kim, H. K.); Kim, H (Kim, H.); Sakong, T (Sakong, T.); Park, Y (Park, Y.); Ha, KH (Ha, K. H.); Nam, OH (Nam, O. H.) Title: High-power AlInGaN-based violet laser diodes with InGaN optical confinement layers - art. no. 091109 Source: APPLIED PHYSICS LETTERS, 93 (9): 91109-91109 SEP 1 2008 Abstract: InGaN optical confinement layers (OCLs) were introduced into blue-violet AlInGaN-based laser diodes (LDs), resulting in the drastic improvements of lasing performance. Comparing with conventional LD structure, the lowest threshold current density of 2.3 kA/cm(2) has been achieved by adding 100-nm-thick InGaN OCLs which represented maximum optical confinement factor. Additionally, we observed the high quantum efficiency and the uniform emission intensity distribution of InGaN quantum wells grown on lower InGaN OCL than on typical GaN layer. Upper InGaN OCL can reduce Mg diffusion from p-type layers to InGaN active region by separating the distance between InGaN quantum wells and p-type layers. (c) 2008 American Institute of Physics. -------------------------------------------------------------------------------117 Author(s): Klehr, A (Klehr, Andreas); Fricke, J (Fricke, Jorg); Knauer, A (Knauer, Arne); Erbert, G (Erbert, Gotz); Walther, M (Walther, Martin); Wilk, R (Wilk, Rafal); Mikulics, M (Mikulics, Martin); Koch, M (Koch, Martin) Title: High-power monolithic two-mode DFB laser diodes for the generation of THz radiation Source: IEEE JOURNAL OF SELECTED TOPICS IN QUANTUM ELECTRONICS, 14 (2): 289-294 MARAPR 2008 Abstract: We have devolved 1064 nm high-power monolithic distributed feedback lasers which operate simultaneously on two longitudinal modes. These modes correspond to the fundamental and first-order lateral mode and arise from a 7.5 mu m width ridge waveguide supporting both of them. They are further stabilized by a first-order grating built into an InGaP/GaAs/InGaP multilayer structure. The threshold current of the laser is 66 mA, the slope efficiency is 0.5 W/A, and an output power of similar to 500 mW is reached. Detailed investigations of the intensity distribution of lateral and vertical far fields and the spectral behavior are shown. The longitudinal mode spacing at 260 mW is 0.56 nm corresponding to approximately 150 GHz. THz generation is demonstrated by mixing the two-line laser emission in a LT-GaAsSb photomixer. Laser Application 118 Author(s): Espejel, F (Espejel, Fulgencio); Roa, JC (Roa, Juan Carlos) Title: Surface enhanced laser desorption/ionization (SELDI): proteomics technology and its application in oncology Source: MEDICINA CLINICA, 131 (8): 312-317 SEP 13 2008 Abstract: Proteomic is the study of proteomes and it involves the global analysis of protein expression profiles, the identification of them and their function in any tissue, organ or organism. Oncoproteomic is the application of proteomics technologies in oncology, which promises to accelerate the discovery of new therapeutics targets and useful biomarkers for diagnosis, prognostic and medical treatment of diverse diseases including cancer. In this context, SELDI (surfaceenhanced laser desorption-ionization) is one of the more used techniques for the development of new tools with clinical utility, among them the discovery of new biomarker molecules that could serve as indicators of both physiological and 最新文献报导 28 XIOPM latest Documents Report disease states. This review covers general aspects of the proteomic techniques and particularly we describe the findings of some studies that used SELDI for the generation of proteomic patterns in order to identify potential biomarkers associated with the diagnosis and prognosis of a variety of cancers. -------------------------------------------------------------------------------119 Author(s): Schmitt, F (Schmitt, F.); Funck, M (Funck, M.); Boglea, A (Boglea, A.); Poprawe, R (Poprawe, R.) Title: Development and application of miniaturized scanners for laser beam micro-welding Source: MICROSYSTEM TECHNOLOGIES-MICRO-AND NANOSYSTEMS-INFORMATION STORAGE AND PROCESSING SYSTEMS, 14 (12): 1861-1869 NOV 2008 Abstract: Nowadays, flexible production systems for laser joining of micro parts require high dynamics and precision, as well as increased flexibility regarding the working space. The combination of miniaturized scanner-based laser joining systems and high-performance assembly systems is a new approach for a high accuracy compact micro assembly system with an increased flexibility. Using highly dynamic oscillation techniques leads to a stabilization of the welding process of difficult-to-weld materials, e.g. of zinc-containing alloys on the one hand, and to an increased process velocity and reduction of the joining geometry, e.g. for the welding of plastic materials on the other. Hence, a miniaturized laser processing optics is being developed featuring an integrated beam deflection for laser beam micro welding of metal as well as plastic materials. The requirements on this laser processing optics, the choice of a suitable beam deflection system and the design and simulation of the miniaturized optics are presented and discussed. Furthermore, results of laser beam micro welding applications are presented. These results directly influence the design of new miniaturized laser processing optics. By means of the integration of highly dynamic scanner devices further process improvements can be achieved for laser beam micro welding. -------------------------------------------------------------------------------120 Author(s): Pinzani, P (Pinzani, Pamela); Lind, K (Lind, Kristina); Malentacchi, F (Malentacchi, Francesca); Nesi, G (Nesi, Gabriella); Salvianti, F (Salvianti, Francesca); Villari, D (Villari, Donata); Kubista, M (Kubista, Mikael); Pazzagli, M (Pazzagli, Mario); Orlando, C (Orlando, Claudio) Title: Prostate-specific antigen mRNA and protein levels in laser microdissected cells of human prostate measured by real-time reverse transcriptase-quantitative polymerase chain reaction and immuno-quantitative polymerase chain reaction Source: HUMAN PATHOLOGY, 39 (10): 1474-1482 OCT 2008 Abstract: Laser-assisted microdissection has mainly been used in cancer studies to excise pure cell populations from heterogeneous tissues. Cancer and normal cells selected by laser-assisted microdissection have frequently been used for mRNA expression studies usually by reverse transcriptase-quantitative polymerase chain reaction (qPCR). Recently, real time immuno-qPCR was developed as a new tool for highly sensitive measurements of proteins. Using reverse transcriptase-qPCR and immuno-qPCR, we measured the amounts of prostate-specific antigen mRNA and its corresponding protein in homogeneous and comparable cell populations, collected from normal and cancer prostates by laser-assisted microdissection. With these techniques, prostate-specific antigen mRNA and protein were quantified over a wide range of concentrations with a sensitivity sufficient to analyze single prostate cells (LNCaP). We did not find significant differences in prostate-specific antigen protein and mRNA between normal and cancer cells. The expression of prostate-specific antigen protein and mRNA was highly correlated in both normal and pathological cells. In microdissected peritubular stromal areas of prostate cancers, the concentration of prostate-specific antigen protein was about 100 times higher than in normal prostate, indicating an increased transit of secreted prostate-specific antigen. In the same samples, prostate-specific antigen mRNA was not detectable. Our data demonstrate, for the first time, the feasibility of simultaneous application of reverse transcriptase-qPCR and immuno-qPCR in studies of homogeneous cell populations, collected by laser-assisted microdissection. The approach is expected to become a very powerful tool for expression studies in human cancers at both mRNA and protein levels. (c) 2008 Elsevier Inc. All rights reserved. -------------------------------------------------------------------------------121 Author(s): Zhang, ZY (Zhang, Zhenyu); Huo, FW (Huo, Fengwei); Jia, ZY (Jia, Zhenyuan); Guo, DM (Guo, Dongming); Jin, ZJ (Jin, Zhuji); Kang, RK (Kang, Renke) Title: Optical properties of La2O3 doped diamond-like carbon films Source: APPLIED SURFACE SCIENCE, 254 (22): 7193-7197 SEP 15 2008 Abstract: A novel kind of La2O3 doped diamond-like carbon (DLC) films with thickness of 100-120 nm were deposited by unbalanced magnetron sputtering. Raman spectra and photoluminescence properties were measured by Raman spectrometer operated by 325 nm He-Cd laser and 514 nm Ar+ laser, respectively. The intensities of Raman spectra and 最新文献报导 29 XIOPM latest Documents Report photoluminescence are higher than those of pure DLC films. The La2O3 doped DLC films have the potential promising for the application of solar cell coatings. (C) 2008 Elsevier B.V. All rights reserved. -------------------------------------------------------------------------------122 Author(s): Bessonov, EG (Bessonov, E. G.); Gorbunkov, MV (Gorbunkov, M. V.); Ishkhanov, BS (Ishkhanov, B. S.); Kostryukov, PV (Kostryukov, P. V.); Maslova, YYA (Maslova, Yu Y. A.); Shvedunov, VI (Shvedunov, V. I.); Tunkin, VG (Tunkin, V. G.); Vinogradov, AV (Vinogradov, A. V.) Title: Laser-electron generator for X-ray applications in science and technology Source: LASER AND PARTICLE BEAMS, 26 (3): 489-495 SEP 2008 Abstract: The possibility of the creation and the application prospects of the laser-electron X-ray generator based on Thomson scattering of laser radiation on a bunch of relativistic electrons are considered. Such a generator fills the existing gap between X-ray tubes and synchrotron radiation sources, which is several orders of magnitude in terms of the brightness. average intensity, size, and also in the construction and running costs. -------------------------------------------------------------------------------123 Author(s): Takahashi, K (Takahashi, Kenshi); Iwasaki, E (Iwasaki, Erika); Matsumi, Y (Matsumi, Yutaka) Title: Vacuum UV laser-induced fluorescence study of the collisional removal of Br(P-2(1/2)) atoms by small molecules Source: CHEMICAL PHYSICS LETTERS, 463 (1-3): 50-53 SEP 22 2008 Abstract: This Letter reports on the application of the vacuum ultraviolet laser-induced fluorescence detection of Br(P-2(1/2)) atoms at 157.48 nm to the kinetic study of collisional removal of Br(P-2(1/2)) by small molecules at 295 K. Gas mixtures of a small amount of CH3Br and an excess amount of collision partners are exposed to pulsed laser irradiation at 193 nm. Temporal decay pro. le of the Br* LIF intensity has been monitored to determine the collisional removal rate coeffficients. The collision partners are H-2, CO2, CF4, CF2H2, H2O, CH3OH, and SF5CF3, and the results are compared to literature data. (c) 2008 Elsevier B. V. All rights reserved. -------------------------------------------------------------------------------124 Author(s): Lee, WR (Lee, Woan-Ruoh); Shen, SC (Shen, Shin-Chuan); Fang, CL (Fang, Chia-Lang); Zhuo, RZ (Zhuo, Rou-Zi); Fang, JY (Fang, Jia-You) Title: Topical delivery of methotrexate via skin pretreated with physical enhancement techniques: Low-fluence Erbium : YAG laser and Electroporation Source: LASERS IN SURGERY AND MEDICINE, 40 (7): 468-476 SEP 2008 Abstract: Background and Objective: The high hydrophilicity and molecular weight of methotrexate (MTX) make it difficult to deliver via the skin route for treating psoriasis or rheumatoid arthritis. The objective of this study was to enhance and optimize the skin permeation of MTX using two physical techniques: an erbium:yttrium-aluminum-garnet (Er:YAG) laser and electroporation. Methods: In vitro skin permeation was performed using horizontal side-by-side diffusion cells. The animal model utilized nude mice. The skin where epidermal hyperproliferation was reproduced by repeated barrier abrogation was also used as a permeation barrier for MTX delivery. Results: Application of the laser and electroporation significantly enhanced the permeation of MTX. The enhancing effect was more pronounced after applying the laser. Er:YAG laser pretreatment on the skin produced a 3- to 80-fold enhancement dependent upon the magnitude of the laser fluence. Using electroporation, treatment with 10 pulses resulted in a twofold increase in MTX flux. A combination of laser pretreatment and subsequent electroporation for 10 minutes resulted in a higher drug permeation than either technique alone. However, this synergistic effect was only observed when the lower laser fluence (1.4 J/cm(2)) was applied. Hyperproliferative skin generally showed a greater variability of MTX flux and lower permeation. Conclusion: The results shown in the present study encourage further investigation of laser- and electroporation-assisted topical drug delivery. -------------------------------------------------------------------------------125 Author(s): Zhang, LL (Zhang, L. L.); Qu, YC (Qu, Y. C.); Zhao, WJ (Zhao, W. J.); Reng, DM (Reng, D. M.); Hu, XY (Hu, X. Y.) Title: A miniature tunable TEA CO2 laser using isotope (CO2)-C-13-O-16 and (CO2)-C-12-O-16 Source: LASER PHYSICS, 18 (9): 1021-1024 SEP 2008 Abstract: 最新文献报导 30 XIOPM latest Documents Report A miniature tunable TEA CO2 laser using isotope (CO2)-C-13-O-16 as the active medium is developed to extend the spectral range of CO2 lasers for further application. The optimization of the energy parameters of the tunable TEA (CO2)-C-13-O-16 laser and the same laser using (CO2)-C-12-O-16 are studied. When a gas mixture ((CO2)-C-13-O-16: N-2: He = 1: 1: 3) at a total pressure of 6.4 x 104 Pa is used, the TEA (CO2)-C-13-O-16 laser of a 45-cm(3) active volume obtains 51 emission lines in the [0001-1000] and [0001-0200] bands. The maximum pulse energy of the TEA (CO2)-C-13-O-16 laser is about 357 mJ. The same laser using the conventional gas mixture ((CO2)-C-12-O-16: N-2: He = 1: 1: 3) at a pressure of 6.66 x 104 Pa is measured to obtain 69 laser emission lines and the maximum pulse energy of laser radiation is about 409 mJ. -------------------------------------------------------------------------------126 Author(s): Queiroga, AS (Queiroga, A. S.); Sousa, FB (Sousa, F. B.); Araujo, JMS (Araujo, J. M. S.); Santos, SD (Santos, S. D.); Sousa, CDS (Sousa, C. D'F. S.); Quintans, TC (Quintans, T. C.); Almeida, TP (Almeida, T. P.); Nonaka, CFW (Nonaka, C. F. W.); Batista, LV (Batista, L. V.); Limeira, FA (Limeira, F. A., Jr.) Title: Evaluation of bone repair in the femur of rats submitted to laser therapy in different wavelengths: An image segmentation method of analysis Source: LASER PHYSICS, 18 (9): 1087-1091 SEP 2008 Abstract: The aim of this study was to histologically assess the effect of laser therapy (LILT, 660 and 780 nm) on the repair of standardized bone defects on the femur of Wistar albinus rats. The sample was composed of 12 Wistar albinus young adult rats of both genders. Three randomized groups were studied: group I (control, n = 4), group II (LILT, 660 nm, n = 4), and group III (LILT, 780 nm, n = 4). Samples were prepared using a bone defect on the left-side femur surface of the animals, with a total dimension of approximately 3 mm(3). Groups II and III were irradiated every 48 h from the second application, where the first dose was given immediately after surgery and the second application came 24 h after surgery. The irradiations were applied transcutaneously at four points around the wound for 14 days. At each point, a dose of 50 J/cm(2) (2 J) was given (s similar to 0.04 cm(2), 40 mW) and the total dose per session was 200 J/cm2 (8 J). The sacrifices were made 15 days after surgery and the specimens were routinely processed to wax, serially cut, stained with an H&E stain, and analyzed under light microscopy. The images were submitted to morphometric analysis using the image segmentation method using the K-means algorithm. The data obtained through the morphometric analysis were submitted to statistical analysis using the Tukey test. The results showed that the group treated with laser therapy in the infrared spectrum resulted in an increase in the repair of bone defects when compared with the group treated with the laser in the red spectrum and control group, which, in turn, had a very similar pattern of repair. A statistical significance (p < 0.01) was observed when comparing the results of group III and the results of Groups I and II. We concluded that the LILT in the infrared spectrum produced a positive biomodulation effect on the repair of bone defects in the femur of rats. -------------------------------------------------------------------------------127 Author(s): Moorthy, I (Moorthy, Inian); Miller, JR (Miller, John R.); Hu, BX (Hu, Baoxin); Chen, J (Chen, Jing); Li, QM (Li, Qingmou) Title: Retrieving crown leaf area index from an individual tree using ground-based lidar data Source: CANADIAN JOURNAL OF REMOTE SENSING, 34 (3): 320-332 JUN 2008 Abstract: Light detection and ranging (lidar) sensors, both at the terrestrial and airborne levels, have recently emerged as useful tools for three-dimensional (3D) reconstruction of vegetated environments. One such terrestrial laser scanner (TLS) is the Intelligent Laser Ranging and Imaging System (ILRIS-3D). The objective of this research was to develop approaches to use ILRIS-3D data to retrieve structural information of an artificial tree in a controlled laboratory experiment. The key crown-level structural parameters investigated in this study were gap fraction, leaf area index (LAI), and clumping index. Measured XYZ point cloud data from a systematically pruned tree were sliced to retrieve laser pulse return density profiles, which subsequently were used to estimate gap fraction, LAI, and clumping index. Gap fraction estimates were cross-validated with traditional methods of histogram thresholding of digital photographs (r(2) = 0.95). LAI estimates from lidar data were corrected for the confounding effects of woody material and nonrandom foliage distribution and then compared with direct LAI measurements (r(2) = 0.98, RMSE = 0.26). The methods developed in this research provide valuable lessons for application to field-level TLS data for structural parameter retrievals. Successful demonstration of analysis protocols to extract crown-level structural parameters like gap fraction, LAI, and clumping index from TLS data will be important for detailed assessments of 3D canopy radiative transfer modeling and likely will lead to more robust inversion algorithms. -------------------------------------------------------------------------------128 Author(s): Radziejewska, J (Radziejewska, J.); Nowicki, B (Nowicki, B.); Kalita, W (Kalita, W.) Title: Laser burnishing method for surface layer modification 最新文献报导 31 XIOPM latest Documents Report Source: PROCEEDINGS OF THE INSTITUTION OF MECHANICAL ENGINEERS PART B-JOURNAL OF ENGINEERING MANUFACTURE, 222 (7): 817-825 JUL 2008 Abstract: The results of experiments on the application of a new hybrid method that combines laser melting treatment with burnishing in hot conditions are presented. Both treatments were performed on the laser station in one operation. The experiments were done on carbon steel C45. The process was performed with a CO2 laser of 2.5 kW maximum power at different parameters. Experiments on the influence of burnishing process parameters on surface layer properties were conducted. The results of measuring the roughness, microstructure, and micro-hardness of the surface layer after laser hardening and after laser hardening combined with microhammering are presented. The microhammering treatment leads to a decrease in surface roughness of about 40 per cent, compared with laser hardening alone. Neither cracks nor spallings were observed. Microstructural analysis has shown that the burnishing process causes deformation of grains and increased microhardness of the material of the surface zone. -------------------------------------------------------------------------------129 Author(s): He, YY (He Yanyan); Li, ZJ (Li Zhengjia); Huang, CY (Huang Chuyun); Yao, YC (Yao Yuncheng) Title: KTP green laser vaporization of biologic tissue under water and its clinical application Source: PHOTOMEDICINE AND LASER SURGERY, 26 (4): 337-341 AUG 2008 Abstract: Objectives: This study aimed to assess the effect of various power settings of the potassium-titanyl-phosphate (KTP) green laser on the vaporization of biological tissue under water and its potential and feasibility to treat patients with benign prostatic hyperplasia (BPH) and other urological disorders. Background Data: BPH, ureteral strictures, and bladder tumors are common urological diseases in elderly men. KTP green laser vaporization is a safe and effective procedure used to treat urological diseases. Methods: Porcine muscles were vaporized at different power levels (7.5-57 W) under water by the KTP green laser system. Fresh canine prostate tissues were also vaporized with a 43-W green laser. Laser vaporization of human urological tissue was performed clinically. Results: The porcine muscles were vaporized under water for 10 sec. Increasing laser power appeared to increase the depth and diameter of vaporization while maintaining or decreasing the depth of necrosis. With the 60-W KTP green laser system, laser prostatectomy was performed on 15 patients with BPH. This green laser system was also used to treat 12 strictures and 9 superficial bladder tumors. All patients received spinal anesthesia, and isotonic saline at room temperature was used as irrigation solution. Postoperative insertion of an indwelling catheter was mandatory. Conclusions: With increasing laser power settings, the vaporization depth and width increased significantly, but the depth of necrosis declined slightly. Green laser vaporization is a treatment method that can be adopted to treat patients with BPH, urethral stricture, and other urological diseases safely and effectively. -------------------------------------------------------------------------------130 Author(s): Ribeiro, IWJ (Ribeiro, Ingrid W. J.); Sbrana, MC (Sbrana, Michyele C.); Esper, LA (Esper, Luis A.); Almeida, ALPF (Almeida, Ana L. P. F.) Title: Evaluation of the effect of the GaAlAs laser on subgingival scaling and root planing Source: PHOTOMEDICINE AND LASER SURGERY, 26 (4): 387-391 AUG 2008 Abstract: Objective: To evaluate the auxiliary effect of the low-intensity laser in subgingival scaling and root planing by analysis of its clinical aspects, as well as its analgesic potential during the procedure. Background Data: Despite the large number of studies conducted on low-intensity laser energy, few clinical studies are available on periodontics. Materials and Methods: Ten patients were selected and submitted to measurement of six sites per tooth, four teeth per hemiarch (960 sites in all). All patients then received subgingival scaling and root planing. Besides periodontal treatment, the test side was also submitted to laser application. The analysis comprised measurement of probing depth, clinical attachment level, and gingival index. Laser energy was applied at a wavelength of 780 nm (35 J/cm(2), 70 mW, 20 sec per site) for preoperative analgesia, and scaling and root planing were performed with application of laser energy at a wavelength of 780 nm (35 J/cm(2), 70 mW, 20 sec) for analgesia, and at a wavelength of 630 nm (8.8 J/cm(2), 35 mW, 10 sec) for healing. The patients filled out a visual analogue scale to assess the pain they felt during the procedure. After 24 and 48 h, the laser was again applied at the wavelength of 630 nm, and the patients were re-evaluated after 3 d. Results: There was a reduction in gingival inflammation, yet without a statistically significant difference between the study and control sides, both in clinical aspects and evaluation of pain during the procedure. Conclusion: Utilization of the diode laser as an auxiliary in subgingival scaling and root planing did not provide any apparent clinical benefit for teeth with shallow to moderate pockets. -------------------------------------------------------------------------------131 Author(s): Pallfy, A (Pallfy, Adriana) 最新文献报导 32 XIOPM latest Documents Report Title: A systematic study of nuclear photoexcitation with X-ray laser fields Source: JOURNAL OF MODERN OPTICS, 55 (16): 2603-2615 2008 Abstract: The resonant driving of nuclear transitions by super-intense X-ray laser fields is studied, considering parameters of upcoming high-frequency coherent light sources. Photoexcitation for a broad range of nuclei initially in the ground state or in a long-lived isomeric state is investigated. The theoretical formalism employed can appropriately account for dipole electric as well as higher multipolarities of the laser-driven nuclear transitions. As an application, we calculate reaction rates for isomer triggering with intense X-ray lasers using realistic parameters for the coherent light source and ion accelerator facilities. A comparison shows that isomer triggering via coupling to the atomic shell is more efficient than via photoexcitation with laser light for the present X-ray laser intensities. -------------------------------------------------------------------------------132 Author(s): Ekici, O (Ekici, O.); Harrison, RK (Harrison, R. K.); Durr, NJ (Durr, N. J.); Eversole, DS (Eversole, D. S.); Lee, M (Lee, M.); Ben-Yakar, A (Ben-Yakar, A.) Title: Thermal analysis of gold nanorods heated with femtosecond laser pulses - art. no. 185501 Source: JOURNAL OF PHYSICS D-APPLIED PHYSICS, 41 (18): 85501-85501 SEP 21 2008 Abstract: We present an axisymmetric computational model to study the heating processes of gold nanoparticles, specifically nanorods, in aqueous medium by femtosecond laser pulses. We use a two-temperature model for the particle, a heat diffusion equation for the surrounding water to describe the heat transfer processes occurring in the system, and a thermal interface conductance to describe the coupling efficiency at the particle/water interface. We investigate the characteristic time scales of various fundamental processes, including lattice heating and thermal equilibration at the particle/surroundings interface, the effects of multiple laser pulses, and the influence of nanorod orientation relative to the beam polarization on energy absorption. Our results indicate that the thermal equilibration at the particle/water interface takes approximately 500 ps, while the electron-lattice coupling is achieved at approximately 50 ps when a 48 x 14 nm(2) gold nanorod is heated to a maximum temperature of 1270 K with the application of a laser pulse having 4.70 J m(-2) average fluence. Irradiation by multiple pulses arriving at 12.5 ns time intervals (80 MHz repetition rate) causes a temperature increase of no more than 3 degrees C during the first few pulses with no substantial changes during the subsequent pulses. We also analyse the degree of the nanorods' heating as a function of their orientation with respect to the polarization of the incident light. Lastly, it is shown that the temperature change of a nanorod can be modelled using its volume-equivalent sphere for femtosecond laser heating within 5-15% accuracy. -------------------------------------------------------------------------------133 Author(s): Kiefer, J (Kiefer, J.); Li, ZS (Li, Z. S.); Zetterberg, J (Zetterberg, J.); Bai, XS (Bai, X. S.); Alden, M (Alden, M.) Title: Investigation of local flame structures and statistics in partially premixed turbulent jet flames using simultaneous single-shot CH and OH planar laser-induced fluorescence imaging Source: COMBUSTION AND FLAME, 154 (4): 802-818 SEP 2008 Abstract: We report on the application of simultaneous single-shot imaging of CH and OH radicals using planar laser-induced fluorescence (PLIF) to investigate partially permixed turbulent jet flames. Various flames have been stabilized on a coaxial jet flame burner consisting of an outer and an inner tube of diameter 22 and 2.2 mm, respectively. From the outer tube a rich methane/air mixture was supplied at a relatively low flow velocity, while a jet of pure air was introduced from the inner one, resulting in a turbulent jet flame on top of a laminar pilot flame. The turbulence intensity was controlled by varying the inner jet flow speed from 0 up to 120 m/s, corresponding to a maximal Reynolds number of the inner jet airflow of 13,200. The CH/OH PLIF imaging clearly revealed the local structure of the studied flames. In the proximity of the burner, a two-layer reaction zone structure was identified where an inner zone characterized by strong CH signals has a typical structure of rich premixed flames. An outer reaction zone characterized by strong OH signals has a typical structure of a diffusion flame that oxidizes the intermediate fuels formed in the inner rich premixed flame. In the moderate-turbulence flow, the CH layers were very thin closed surfaces in the entire flame, whereas the OH layers were much thicker. In the high-intensity-turbulence flame, the CH layer remained thin until it vanished in the upper part of the flame, showing local extinction and reignition behavior of the flame. The single-shot PLIF images have been utilized to determine the flame surface density (FSD). In low and moderate turbulence intensity cases the FSDs determined from CH and OH agreed with each other, while in the highly turbulent case a locally broken CH layer was observed, leading to a significant difference in the FSD results determined via the OH and CH radicals. Furthermore, the means and the standard deviations of CH and OH radicals were obtained to provide statistical information about the flames that may be used for validation of numerical calculations. (C) 2008 The Combustion Institute. Published by Elsevier Inc. All rights reserved. -------------------------------------------------------------------------------- 最新文献报导 33 XIOPM latest Documents Report 134 Author(s): Wiles, MD (Wiles, M. D.); Dickson, E (Dickson, E.); Moppett, IK (Moppett, I. K.) Title: Transient hyperaemic response to assess vascular reactivity of skin: effect of topical anaesthesia Source: BRITISH JOURNAL OF ANAESTHESIA, 101 (3): 320-323 SEP 2008 Abstract: Background. Local anaesthetics affect blood vessels in various ways, depending upon the site of action and the drug used. There is controversy over the vascular effects of two widely used topical local anaesthetic agents, EMLA (R) and Ametop (R). We used the transient hyperaemic response (THR) to the brief compression of the brachial artery to assess vascular reactivity of forearm skin after application of topical local anaesthesia. Methods. Twenty healthy male volunteers were studied. Forearm blood flow-flux was measured using laser Doppler flowmetry, and the magnitude of the hyperaemic response to brachial artery occlusion for 20 s was recorded. Control cream, EMLA (R), or Ametop (R) were applied and covered with an occlusive dressing for 60 min. Blood flow-flux and the hyperaemic response measurements were then repeated, with the laser Doppler probes sited over the areas of skin to which the local anaesthetic creams had been applied. Measurements were made at 60, 90, and 120 min after the application of the creams. The THR ratio (THRR) was calculated at each time point, defined as the net hyperaemic flow-flux divided by the baseline flow-flux. Results. At 60 min, Ametop caused a significantly greater increase in blood flow and decrease in THRR over control than EMLA [ net increase of mean blood flow (SD) over control 95 ( 61) vs 2 (17) AU (P<0.001), net mean THRR decrease over control 1.33 (1.85) vs -0.34 (1.33) (P<0.02)]. Conclusions. The application of topical Ametop decreases microvascular tone and vasoreactivity of the forearm skin in healthy volunteers. -------------------------------------------------------------------------------135 Author(s): Ameri, H (Ameri, Hossein); Ratanapakorn, T (Ratanapakorn, Tanapat); Rao, NA (Rao, Narsing A.); Chader, GJ (Chader, Gerald J.); Humayun, MS (Humayun, Mark S.) Title: Natural course of experimental retinal vein occlusion in rabbit; arterial occlusion following venous photothrombosis Source: GRAEFES ARCHIVE FOR CLINICAL AND EXPERIMENTAL OPHTHALMOLOGY, 246 (10): 1429-1439 OCT 2008 Abstract: Background Retinal vein occlusion (RVO) is the second leading cause of vascular eye disease. Currently there is no definite treatment for this condition. Animal models could be potentially helpful in developing new treatments; however, it is essential to understand the differences these models may have with human RVO. The aim of our study was to examine the course of experimentally created retinal vein occlusion (RVO) in rabbits. Methods Twenty-nine pigmented rabbits were included in the study. RVO was created in all using an argon green laser following intravenous injection of Rose Bengal. A laser was applied to all major veins at the optic disc margin to mimic central retinal vein occlusion. Animals were followed-up for a maximum of 2 months. Results Immediately following laser application, blood flow ceased or the flow was extremely slow in the retinal veins in all cases. At day 2 post laser, 86% showed significant retinal hemorrhages. On FA, no retinal blood flow was observed in the eye (neither arteries nor veins) in the majority of rabbits. Between weeks 1 and 3, laser sites reopened and partial or complete revascularization of both retinal arteries and veins occurred; however, the vascular pattern was abnormal. Conclusions RVO in rabbits has a different course than in human and it can be classified into three stages. At stage 1 (the first few days after laser photothrombosis), there is a retrograde propagation of the blood clot in the retinal veins that extends to the retinal arteries and choriocapillaries. As a result, there is no retinal blood flow at this stage in most cases. At stage 2 (between weeks 1 and 3), partial or complete revascularization occurs but the vessels have an abnormal pattern. At stage 3 (after week 3) no significant change takes place. -------------------------------------------------------------------------------136 Author(s): Friedrich, CS (Friedrich, Claus-Stefan); Brenner, C (Brenner, Carsten); Hoffmann, S (Hoffmann, Stefan); Schmitz, A (Schmitz, Andreas); Mayorga, IC (Mayorga, Ivan Camara); Klehr, A (Klehr, Andreas); Erbert, G (Erbert, Goetz); Hofmann, MR (Hofmann, Martin R.) Title: New two-color laser concepts for THz generation Source: IEEE JOURNAL OF SELECTED TOPICS IN QUANTUM ELECTRONICS, 14 (2): 270-276 MARAPR 2008 Abstract: Two-color semiconductor external cavity laser concepts for terahertz (THz) generation are discussed. By defining three critical characteristics, various two-color laser configurations are experimentally classified with respect to the 最新文献报导 34 XIOPM latest Documents Report application of THz generation. According to our experimental results, we suggest a new two-color laser configuration. It is based on an external cavity with an etalon. -------------------------------------------------------------------------------137 Author(s): Yun, HG (Yun, Ho-Gyeong); Choi, KS (Choi, Kwang-Seong); Kwon, YH (Kwon, Yong-Hwan); Choe, JS (Choe, Joong-Seon); Moon, JT (Moon, Jong-Tae) Title: Fabrication and characteristics of 40-Gb/s traveling-wave electroabsorption modulator-integrated DFB laser modules Source: IEEE TRANSACTIONS ON ADVANCED PACKAGING, 31 (2): 351-356 MAY 2008 Abstract: We have developed 40-Gb/s traveling-wave electroabsorption-modulator-integrated distributed feedback laser (TWEML) modules using several advanced technologies. First, we have adopted a selective area growth (SAG) method in the fabrication of the 40-Gb/s EML device to provide active layers for the laser and the electroabsorption modulators (EAMs) simultaneously. The fabricated device shows that the measured 3-dB bandwidth of electrical-to-optical (E/O) response reaches about 45 GHz and the return loss (S-11) is kept below -10 dB up to 50 GHz. For the module design of the device, we mainly considered electrical and optical factors. The measured S of the fabricated 40 Gb/s TW-EML module is below -10 dB up to about 30 GHz and the 3-dB bandwidth of the E/O response reaches over 35 GHz. We also have developed two types of coplanar waveguide (CPW) for the application of the driver amplifier integrated 40 Gb/s TW-EML module, which is a system-on-package (Sol?) composed of an EML device and a driver amplifier device in a module. The measured S-11 of the two-step-bent CPW is below -10 dB up to 35 GHz and the measured S-11 of the parallel type CPW is below -10 dB up to 39 GHz. Nonlinear Optics 138 Author(s): Seki, K (Seki, Kyota); Yamashita, S (Yamashita, Shinji) Title: Narrowband and tunable optical parametric amplification in Bismuth-Oxide-based highly nonlinear fiber Source: OPTICS EXPRESS, 16 (18): 13871-13877 SEP 1 2008 Abstract: The one-pump optical fiber parametric amplification (FOPA) has been well known to be a means for realizing wideband amplification when the group-delay dispersion (beta(2)) is small at the pump wavelength. In this paper, we report onepump FOPA in short Bismuth-Oxide-based highly nonlinear fiber (Bi-HNLF) that has large normal dispersion at 1550nm, both theoretically and experimentally, for the first time to the best of our knowledge. We found that, due to the large beta(4) along with large beta(2), FOPA in the Bi-HNLF is very narrowband, and its gain peak wavelength is tunable in proportional to the pump wavelength. We achieved the gain bandwidth as narrow as 0.75nm and gain peak as high as 58dB in the experiment using a 2m-long Bi-HNLF. (c) 2008 Optical Society of America. -------------------------------------------------------------------------------139 Author(s): Pan, ZR (Pan, Zhao Rui); Zhang, YC (Zhang, You Cai); Song, YL (Song, Ying Lin); Zhuo, X (Zhuo, Xin); Li, YZ (Li, Yi Zhi); Zheng, HG (Zheng, He Gen) Title: Synthesis, structure and nonlinear optical properties of three dimensional compounds Source: JOURNAL OF COORDINATION CHEMISTRY, 61 (20): 3189-3199 2008 Abstract: The combination of metal ions with H(3)tbba has resulted in the formation of two three dimensional coordination compounds {[Zn(H(2)tbba)(2)(H2O)]center dot 2(OC3H6)}(n) (1) and {[Mn(H(2)tbba)(2)(H2O)]center dot 2(OC3H6)}(n) (2) (H(2)tbba = 2-thiobarbituric acid anion). Compounds 1 and 2 are isostructural with metal ions bridged by four hydroxyl oxygens from four different H2tbba ligands to form a 3D network. H(2)tbba exhibits bidentate coordination with both hydroxyl oxygens participating in coordination, a new coordination mode. Nonlinear absorption and refraction of 1 and 2 in DMF are studied by using Z-scan measurement technique at 532 nm. 1 and 2 possess nonlinear optical absorption and self-focusing. -------------------------------------------------------------------------------140 Author(s): Srinivasan, P (Srinivasan, P.); Kanagasekaran, T (Kanagasekaran, T.); Lal, DK (Lal, D. Kanji); Gopalakrishnan, R (Gopalakrishnan, R.); Ramasamy, P (Ramasamy, P.) Title: Contemplations on the impressions of MeV swift heavy ion irradiation on nonlinear optical dimethylamino-pyridinium-4-nitrophenolate-4-nitro-phenol (DMAPNP) single crystals Source: RADIATION EFFECTS AND DEFECTS IN SOLIDS, 163 (8): 693-702 2008 最新文献报导 35 XIOPM latest Documents Report Abstract: Organic nonlinear optical crystal dimethyl-amino-pyridinium-4-nitrophenolate-4-nitro-phenol was subjected to 100MeV Ag8+ ions and 50MeV Si8+ ions. The radiation effects are studied in terms of processes observed with the pristine samples and in comparison with them. The dielectric properties of the crystals were studied before and after irradiation from 100 Hz to 5 MHz at various temperatures (308-383K). A drastic increase in the dielectric constant is seen due to irradiation. The dielectric constant and conductivity increases with the increase of irradiation fluence for the samples. The observed results are discussed in detail. -------------------------------------------------------------------------------141 Author(s): Tatarinova, LL (Tatarinova, Larisa L.); Garcia, ME (Garcia, Martin E.) Title: Exact solutions of the eikonal equations describing self-focusing in highly nonlinear geometrical optics - art. no. 021806 Source: PHYSICAL REVIEW A, 78 (2): 1806-1806 Part A AUG 2008 Abstract: We demonstrate that laser beam collapse in highly nonlinear media can be described, for a large number of experimental conditions, by the geometrical optics approximation within high accuracy. Taking into account this fact we succeed in constructing analytical solutions of the eikonal equation, which are exact on the beam axis and provide (i) a firstprinciples determination of the self-focusing position, thus replacing the widely used empirical Marburger formula, (ii) a mathematical condition for obtaining the filament intensity, (iii) a benchmark solution for numerical simulations, and (iv) a tool for the experimental determination of the high-order nonlinear susceptibility. Successful comparison with experiment is presented. -------------------------------------------------------------------------------142 Author(s): Li, HJ (Li, Hui-jun); Hang, C (Hang, Chao); Huang, GX (Huang, Guoxiang); Deng, L (Deng, L.) Title: High-order nonlinear Schrodinger equation and superluminal optical solitons in room-temperature activeRaman-gain media - art. no. 023822 Source: PHYSICAL REVIEW A, 78 (2): 3822-3822 Part B AUG 2008 Abstract: We make a detailed study on the dynamics of gain-assisted superluminal optical solitons in a three-state active-Ramangain medium at room temperature. Using a method of multiple-scales we derive a high-order nonlinear Schrodinger equation with correction terms contributed from differential gain, nonlinear dispersion, delay in nonlinear refractive index, and third-order dispersion of the system. We show that for a long pulse with realistic physical parameters the high-order correction terms are small and can be taken as perturbations. However, for a shorter pulse these higher-order correction terms are significant and hence must be treated on equal footing as the terms in the nonlinear Schrodinger equation. We provide exact soliton solutions of the higher-order nonlinear Schrodinger equation and demonstrate that such solitons have still superluminal propagating velocity and can be generated at very low light intensity. -------------------------------------------------------------------------------143 Author(s): Larson, AM (Larson, Adam M.); Yeh, AT (Yeh, Alvin T.) Title: Delivery of sub-10-fs pulses for nonlinear optical microscopy by polarization-maintaining single mode optical fiber Source: OPTICS EXPRESS, 16 (19): 14723-14730 SEP 15 2008 Abstract: Broadband, sub-10-fs pulses, can be propagated through polarization-maintaining single mode fiber (PMF) for use in nonlinear optical microscopy (NLOM). We demonstrate delivery of near transform-limited, 1 nJ pulses from a Ti: Al2O3 (75 MHz repetition rate) oscillator via PMF to the NLOM focal plane while maintaining 120 nm of bandwidth. Negative group delay dispersion (GDD) introduced to pre-compensate normal dispersion of the optical fiber and microscope optics ensured linear pulse propagation through the PMF. The minimized time-bandwidth product of the laser pulses at the NLOM focus allowed the nonlinear excitation of multiple fluorophores simultaneously without central wavelength tuning. Polarization sensitive NLOM imaging using second harmonic generation in collagen was demonstrated using PMF delivered pulses. Two-photon excited fluorescence spectra and second harmonic images taken with and without the fiber indicates that the fiber based system is capable of generating optical signals that are within a factor of two to three of our traditional NLOM. (C) 2008 Optical Society of America. -------------------------------------------------------------------------------144 Author(s): Khoo, IC (Khoo, I. C.); Werner, DH (Werner, D. H.); Kwon, DH (Kwon, D. H.); Diaz, A (Diaz, A.) Title: Designing liquid crystalline nonlinear optical meta-materials with large birefringence and sub-unity refractive index Source: MOLECULAR CRYSTALS AND LIQUID CRYSTALS, 488: 88-99 2008 最新文献报导 36 XIOPM latest Documents Report Abstract: We describe here two types of liquid crystalline meta-materials which exhibit large birefringence and sub-unity or negative refractive index. The conditions on the constituents' complex permittivity and permeability for producing effective refractive indices in this unconventional range are explicitly illustrated with two exemplary liquid crystalline meta-materials: (i) core-shell nano-spheres randomly dispersed in a nematic liquid crystal and (ii) planar nano-structures juxtaposed with a layer of liquid crystal. Both systems also exhibit enhanced electro-optical and nonlinear optical responses. These meta-materials may find applications in the next generation reflective, transmissive, modulation and switching elements and devices in the visible-infrared-Terahertz and microwave regimes. -------------------------------------------------------------------------------145 Author(s): Singh, M (Singh, M.); Joseph, D (Joseph, D.); Duhan, S (Duhan, S.) Title: Nonlinear optical parameters of magnetoactive semiconductor-plasmas Source: INTERNATIONAL JOURNAL OF MODERN PHYSICS B, 22 (22): 3877-3887 SEP 10 2008 Abstract: The nonlinear optical parameters (absorption coefficient and refractive index) of semiconductor-plasmas subjected to a transverse magnetic field have been investigated analytically. By employing the coupled-mode scheme, an expression of third-order optical susceptibility and resultant nonlinear absorption and refractive index of the medium are obtained. The analysis has been applied to both cases, viz., centrosymmetric (beta = 0) and noncentrosymmetric (beta not equal 0) in the presence of magnetic field. The numerical estimates are made for InSb crystal at liquid nitrogen temperature duly irradiated by a 10-nanosecond pulsed 10.6 mu m CO2 laser. The influence of doping concentration and magnetic field on both the nonlinear absorption and refractive index has been explored, and the results are found to be well in agreement with theory and experiment. Analysis further establishes that absorption coefficient and refractive index can be controlled with precision in semiconductors by the proper selection of doping concentration and an external magnetic field, and hence these media may be used for fabrication of fast cubic nonlinear optical devices under off-resonant transition regime. -------------------------------------------------------------------------------146 Author(s): Xiao, DQ (Xiao, Dequan); Bulat, FA (Bulat, Felipe A.); Yang, WT (Yang, Weitao); Beratan, DN (Beratan, David N.) Title: A donor-nanotube paradigm for nonlinear optical materials Source: NANO LETTERS, 8 (9): 2814-2818 SEP 2008 Abstract: Studies of the nonlinear electronic response of donor/acceptor substituted nanotubes suggest a behavior that is both surprising and qualitatively distinct from that in conventional conjugated organic species. We find that the carbon nanotubes serve as both electronic bridges and acceptors, leading to a donor-nanotube paradigm for the effective design of large first hyperpolarizabilities. We also find that tuning the donor orientation, relative to the nanotube, can significantly enhance the first hyperpolarizability. -------------------------------------------------------------------------------147 Author(s): Li, Y (Li, Yan); Xu, G (Xu, Gang); Zou, WO (Zou, Wen-Oiang); Wang, NS (Wang, Nling-Sheng); Zheng, FK (Zheng, Fa-Kun); Wu, MF (Wu, Mei-Feng); Zeng, HY (Zeng, Hui-Yi); Guo, GC (Guo, Guo-Cong); Huang, JS (Huang, Jin-Shun) Title: A novel metal-organic network with high thermal stability: Nonlinear optical and photoluminescent properties Source: INORGANIC CHEMISTRY, 47 (18): 7945-7947 SEP 15 2008 Abstract: A novel zinc(II) 4-(5H-tetrazol)benzoic coordination polymer with an in situ generated tetrazole ligand exhibits the gsi (gamma-silicon) topology and high thermal stability; this compound possesses second-order nonlinear optical and interesting heat-induced photoluminescent properties. -------------------------------------------------------------------------------148 Author(s): Kirubavathi, K (Kirubavathi, K.); Selvaraju, K (Selvaraju, K.); Vijayan, N (Vijayan, N.); Kumararaman, S (Kumararaman, S.) Title: Growth and characterization of glycine hydrobromide single crystal for nonlinear optical appications Source: MODERN PHYSICS LETTERS B, 22 (21): 2035-2042 AUG 20 2008 Abstract: Single crystals of a new semi-organic nonlinear optical material glycine hydrobromide were grown from solution by slow evaporation at room temperature. Good optical quality single crystals with dimensions 17x8x5 mm(3) were obtained. The grown crystal had been confirmed by single-crystal X-ray diffraction and the vibrational frequencies of 最新文献报导 37 XIOPM latest Documents Report various functional groups in the crystals had been derived from Fourier transform infrared spectrum. The optical quality of the grown crystals was analyzed by the Ultraviolet visible spectrum method. The mechanical behavior of the grown crystal was evaluated by Vickers' micro-hardness in dentation method. Then nonlinear optical property of the crystal was confirmed by the Kurtz powder technique using Nd:YAG laser as a source -------------------------------------------------------------------------------149 Author(s): Pan, SL (Pan, Shilie); Smit, JP (Smit, Jared P.); Marvel, MR (Marvel, Michael R.); Stampler, ES (Stampler, Evan S.); Haag, JM (Haag, Jacob M.); Baek, J (Baek, Jaewook); Halasyamani, PS (Halasyamani, P. Shiv); Poeppelmeier, KR (Poeppelmeier, Kenneth R.) Title: Synthesis, crystal structure, and nonlinear optical properties of Bi2Cu5B4O14 Source: JOURNAL OF SOLID STATE CHEMISTRY, 181 (8): 2087-2091 AUG 2008 Abstract: Bi2Cu5B4O14 crystallizes in the noncentrosymmetric triclinic space group P1 (No. 1) with cell parameters a = 10.1381(11)angstrom, b = 9.3917(11)angstrom, c = 3.4566(4)angstrom, alpha = 105.570(2)(-), beta = 92.275(2)(-), gamma = 107.783(2), Z = 1 and R-1 = 0.0401 and w/R-2 = 0.0980. It is a layered structure that is built up from sheets of rectangular CuO4 and trigonal BO3 groups. The sheets are connected by infinite chains of edge shared BiO6 polyhedra that intersect the bc plane at an angle slightly greater than 90 degrees C. The Second-harmonic generation efficiency of Bi2Cu5B4O14, using 1064 nm radiation, is about one half times that of KH2PO4. (C) 2008 Elsevier Inc. All rights reserved. -------------------------------------------------------------------------------150 Author(s): Chi, YM (Chi, Yue-meng); Shi, JJ (Shi, Jun-jie) Title: Built-in electric field effect on the linear and nonlinear intersubband optical absorptions in InGaN strained single quantum wells Source: JOURNAL OF LUMINESCENCE, 128 (11): 1836-1840 NOV 2008 Abstract: Considering the strong built-in electric field (BEF) induced by the spontaneous and piezoelectric polarizations and the intrasubband relaxation, we investigate the linear and nonlinear intersubband optical absorptions in InxGa1-xN/AlyGa1yN strained single quantum wells (QWs) by means of the density matrix formalism. Our numerical results show that the strong BEF is on the order of MV/cm, which can be modulated effectively by the In composition in the QW. This electric field greatly increases the electron energy difference between the ground and the first excited states. The electron wave functions are also significantly localized in the QW due to the BEF. The intersubband optical absorption peak sensitively depends on the compositions of In in the well layer and Al in the barrier layers. The intersubband absorption coefficient can be remarkably modified by the electron concentration and the incident optical intensity. The group-M nitride semiconductor QWs are suitable candidate for infrared photodetectors and near-infrared laser amplifiers. (C) 2008 Elsevier B.V. All rights reserved. -------------------------------------------------------------------------------151 Author(s): Irimpan, L (Irimpan, Litty); Krishnan, B (Krishnan, Bindu); Nampoori, VPN (Nampoori, V. P. N.); Radhakrishnan, P (Radhakrishnan, P.) Title: Linear and nonlinear optical characteristics of ZnO-SiO2 nanocomposites Source: APPLIED OPTICS, 47 (24): 4345-4351 AUG 20 2008 Abstract: We present the spectral and nonlinear optical properties of ZnO-SiO2 nanocomposites prepared by colloidal chemical synthesis. Obvious enhancement of ultraviolet (UV) emission of the samples is observed, and the strongest UV emission of a typical ZnO-SiO2 nanocomposite is over three times stronger than that of pure ZnO. The nonlinearity of the silica colloid is low, and its nonlinear response can be improved by making composites with ZnO. These nanocomposites show self-defocusing nonlinearity and good nonlinear absorption behavior. The observed nonlinear absorption is explained through two photon absorption followed by weak free carrier absoption and nonlinear scattering. The nonlinear refractive index and the nonlinear absorption increase with increasing ZnO volume fraction and can be attributed to the enhancement of exciton oscillator strength. ZnO-SiO2 is a potential nanocomposite material for the UV light emission and for the development of nonlinear optical devices with a relatively small limiting threshold. (C) 2008 Optical Society of America. -------------------------------------------------------------------------------152 Author(s): Taya, SA (Taya, Sofyan A.); Shabat, MM (Shabat, Mohammed M.); Khalil, HM (Khalil, Hala M.); Jager, DS (Jaeger, Dieter S.) Title: Theoretical analysis of TM nonlinear asymmetrical waveguide optical sensors Source: SENSORS AND ACTUATORS A-PHYSICAL, 147 (1): 137-141 SEP 15 2008 最新文献报导 38 XIOPM latest Documents Report Abstract: An extensive analytical analysis is carried out to investigate TM nonlinear asymmetrical waveguide sensors. The structure consists of a thin film embedded between two nonlinear media. The effect of the nonlinearity of the cladding and the substrate on the sensitivity of the sensor is studied. A comparison between the proposed nonlinear sensor and the conventional linear sensor is presented to show that nonlinear sensors have higher sensitivities. The condition required to maximize the sensitivity is also derived to provide the designer with the optimum structure of the proposed nonlinear sensor. (C) 2008 Elsevier B.V. All rights reserved. -------------------------------------------------------------------------------153 Author(s): Li, LL (Li, Ling-Ling); Ren, ZG (Ren, Zhi-Gang); Wang, J (Wang, Jing); Wei, ZH (Wei, Zhen-Hong); Huang, YJ (Huang, Yu-Jian); Zhang, Y (Zhang, Yong); Lang, JP (Lang, Jian-Ping); Deng, L (Deng, Li); Sun, ZR (Sun, Zhen-Rong) Title: Syntheses, crystal structures and third-order nonlinear optical properties of [PPh4](2)[(WS4)M(mudppe)(2)M(WS4)]center dot 2CH(2)Cl(2) from the preformed polymeric clusters {[PPh4][WS4M]}(n) (M = Ag, Cu) Source: JOURNAL OF MOLECULAR STRUCTURE, 886 (1-3): 121-127 AUG 27 2008 Abstract: Reactions of {[PPh4][WS4M]}(n) (1: M = Ag; 2: M = Cu) with equimolar 1,2-bis(diphenylphosphino)ethane (dppe) in CH2Cl2 produced two tetranuclear anionic clusters [PPh4](2)[(WS4)M(mu-dppe)(2)M(WS4)]center dot 2CH(2)Cl(2) (3: M = Ag; 4: M = Cu). Both clusters were characterized by elemental analysis, IR, UV-vis, H-1 NMR and singlecrystal X-ray analysis. The centrosymmetric structure of the cluster dianion of 3 or 4 consists of two [WS4M] cluster fragments linked by a pair of dppe ligands. The third-order nonlinear optical (NLO) properties of 3 and 4 in solution were investigated by femtosecond degenerate four-wave mixing (DFWM) technique with a 80-fs pulsed laser at 800 nm. Both compounds exhibited strong NLO performances with chi((3)) = 3.30 x 10(-14) esu or 2.89 x 10(-14) esu (4), and gamma = 1.064 x 10(-31) esu (3) or 1.059 x 10(-31) esu (4). (C) 2007 Elsevier B.V. All rights reserved. -------------------------------------------------------------------------------154 Author(s): Stupakiewicz, A (Stupakiewicz, A.); Kirilyuk, A (Kirilyuk, A.); Maziewski, A (Maziewski, A.); Rasing, T (Rasing, Th.); Wawro, A (Wawro, A.); Baczewski, LT (Baczewski, L. T.) Title: Linear and nonlinear magneto-optical response of ultrathin Co/Au/Mo and Co/Mo films grown on sapphire substrates Source: PHYSICA STATUS SOLIDI A-APPLICATIONS AND MATERIALS SCIENCE, 205 (8): 1770-1773 AUG 2008 Abstract: We report studies of the linear and nonlinear magneto-optical properties of epitaxial Ultrathin Co films grown on sapphire substrates covered with Mo or Mo/Au buffers. Changes of the crystallographic symmetry and magnetization of buried interfaces were deduced from the magneto-optical Kerr effect hysteresis loops and magnetization-induced second-harmonic generation (MSHG). Depending on the buffer, two-fold (for Mo buffer) or six-fold (for Mo/Au buffer) symmetries were observed in both inplane magnetic anisotropy and MSHG intensity. (C) 2008 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim. -------------------------------------------------------------------------------155 Author(s): Luo, SJ (Luo, S. J.); Du, WF (Du, W. F.); Wang, HZ (Wang, H. Z.) Title: A first-principles study of linear and nonlinear optical properties of 4-nitro-4 '-methylbenzylidene aniline art. no. 094705 Source: JOURNAL OF CHEMICAL PHYSICS, 129 (9): 94705-94705 SEP 7 2008 Abstract: First-principles calculations of two second-order optical response functions as well as the dielectric function for 4-nitro4'-methylbenzylidene aniline are performed. Specifically, we evaluate the dielectric function and the second-harmonic generation (SHG) response coefficient over a wide frequency range. Electronic structure obtained from the full-potential projected augmented wave method is adopted in the calculation of optical properties. The calculated results of the refractive indices and the SHG are in good agreement with the experimental values. The linear and nonlinear optical spectra are analyzed and the origins of the peaks in the spectra are discussed in terms of the calculated electronic structure. It is found that the origin of the large nonlinear optical susceptibility is the charge transfer due to the strong "push-pull" effect. The study of the contributions of different transitions to the SHG coefficients shows that the virtual electron process is main. The contribution to the largest component chi((2))(11) of the virtual hole process is about 30% of the total static limit of the SHG coefficient. The prominent features in the spectrum of chi((2))(11) are successfully correlated with the features of the linear dielectric function epsilon(omega) in terms of single-photon and two-photon resonances. (C) 2008 American Institute of Physics. 最新文献报导 39 XIOPM latest Documents Report -------------------------------------------------------------------------------156 Author(s): Liu, T (Liu, T.); Qin, J (Qin, J.); Zhang, G (Zhang, G.); Zhu, T (Zhu, T.); Niu, F (Niu, F.); Wu, Y (Wu, Y.); Chen, C (Chen, C.) Title: Mercury Bromide (HgBr2): A promising nonlinear optical material in IR region with a high laser damage threshold - art. no. 091102 Source: APPLIED PHYSICS LETTERS, 93 (9): 91102-91102 SEP 1 2008 Abstract: Nonlinear optical (NLO) crystals have played a key role in laser technology, and the existing materials for the IR range showed relatively low laser damage threshold in common. A NLO material HgBr2 is presented here. It shows a powder second harmonic generation about ten times as large as that of KH2PO4, a wide transparency in whole mid-IR region (from 2.5 to 25 mu m), and a good stability to the environment. Most importantly it exhibits a high laser damage threshold of about 0.3 GW/cm(2). Therefore, it is believed that HgBr2 is a promising candidate for NLO materials in the IR region. (c) 2008 American Institute of Physics. -------------------------------------------------------------------------------157 Author(s): Wang, X (Wang, Xin); Guang, SY (Guang, Shanyi); Xu, HY (Xu, Hongyao); Su, XY (Su, Xinyan); Yang, JY (Yang, Junyi); Song, YL (Song, Yinglin); Lin, NB (Lin, Naibo); Liu, XY (Liu, Xiangyang) Title: Thermally stable oxadiazole-containing polyacetylenes: Relationship between molecular structure and nonlinear optical properties Source: JOURNAL OF MATERIALS CHEMISTRY, 18 (35): 4204-4209 2008 Abstract: Two novel high molecular weight functional polyacetylenes bearing oxadiazole groups as pendants, poly(2-(4decyloxyphenyl)-5-(4-ethynylphenyl)-1, 3, 4-oxadiazole) (P1) and poly(2-(4-butyloxyphenyl)- 5-(4-ethynylphenyl)-1, 3, 4-oxadiazole) (P2) were designed and synthesized by a multistep reaction route. The structures and properties were characterized and evaluated with FTIR, NMR, UV, TGA, GPC, optical-limiting (OL) and nonlinear optical (NLO) analyses. The incorporation of oxadiazole into polyacetylene significantly endows polyacetylenes with higher thermal stability and optical limiting property. The solubility, stereoregularity and optical properties of resultant polyacetylenes are obviously affected by flexible terminal alkoxy chain length. The cis olefinic structure content in polyacetylene backbone increases with increasing terminal alkoxy group length. The functional polyacetylene with the higher cis olefinic structure content shows higher thermal stability, better optical limiting property and larger third-order nonlinear optical performance. The optical limiting mechanism of resulting polymers was investigated, which is mainly originated from larger excitation state absorption cross-section of molecules to result in reverse saturable absorption. Space Optical System 158. Mobile free space optical communication system Wang, Xian (Electrical Engineering Department, California Polytechnic State University); Hsu, Chi Yeh; Jin, Xiaomin Source: Proceedings of SPIE - The International Society for Optical Engineering, v 6877, Free-Space Laser Communication Technologies XX, 2008, p 687706 ISSN: 0277-786X CODEN: PSISDG Conference: Free-Space Laser Communication Technologies XX, Jan 24 2008, San Jose, CA, United States Sponsor: Society of Photo-Optical Instrumentation Engineers (SPIE) Publisher: SPIE Abstract: The paper discusses a low power consumption, light weight and low cost 10MHz free-space optical communication (FSO). The system is designed for mounting on mobile platforms, with effective range of at least 50 meters. Light-Emitting Diodes (LEDs) and Laser diodes (LDs) are used in the transmitter for comparison for their relative performance in the system. The receiver features a beam splitter that feeds part of the data link optical signal to a quadrant photodetector and controls a tracking/stabilization system using microcontroller. Since almost all commercial FSO systems are mounted on fixed positions such as buildings, the paper explores the possibility and challenges of designing a FSO system for a mobile system such as remotely operated-vehicles or between ships. (16 refs.) 159 Free space optical MIMO system using PPM modulation and a single optical amplifier 最新文献报导 40 XIOPM latest Documents Report Cao, Qianling (Charles L. Brown Department of Electrical and Computer Engineering, University of Virginia); BrandtPearce, Maite; Wilson, Stephen G. Source: Proceedings of the Second International Conference on Communications and Networking in China, ChinaCom 2007, Proceedings of the Second International Conference on Communications and Networking in China, ChinaCom 2007, 2008, p 508-512 Conference: 2007 2nd International Conference on Communications and Networking in China, ChinaCom 2007, Aug 22-24 2007, Shanghai, China Publisher: Institute of Electrical and Electronics Engineers Inc. Abstract: The use of an optical pre-amplifier in a multiple laser multiple receive aperture system for atmospheric lineof-sight optical communications is investigated Multiple transmit-receive paths serve to fight channel fading due to clear air scintillation. Using orthogonal polarization and repetition coding cross two lasers is shown to provide transmitter diversity. Receiver diversity can be obtained by using optical phase shifters to counter channel phase offsets. Binary pulse position modulation (PPM) is proposed and analyzed in the presence of background radiation and amplified spontaneous emission noise. Using an optical pre-amplifier in a multlple-input/multiple-output channel results in significantly better performance than using an electrical amplifier. (9 refs.) 160. Free space optical channel parameters estimation for high altitude platform system Tosovsky, Petr (Dept. of Radio Electronics, Brno University of Technology); Dordova, Lucie Source: Proceedings of the 14th Conference on Microwave Techniques, COMITE 2008, Proceedings of the 14th Conference on Microwave Techniques, COMITE 2008, 2008, p 4569955 Conference: 14th Conference on Microwave Techniques, COMITE 2008, Apr 23-24 2008, Prague, Czech Republic Publisher: Institute of Electrical and Electronics Engineers Computer Society Abstract: Requirements on computer networks speed are steadily increasing. Unfortunately it is not possible to use a classic fiber optic backbone networks in all areas due to very high cost of this system. High altitude platform system offers communication on long distance with a great degree of flexibility. In combination with free space optics it provides low cost solution with high rate-speed. However as an atmosphere is used as the transfer medium disadvantage of this solution is dependency on atmospheric conditions. To guarantee 100% link availability it is necessary to create backup transfer channel. Following article estimates the main parameters of atmosphere and compares them with basic requirements on free space optics communication parts - transmitter and receiver. © 2008 IEEE. (3 refs.) 161. Sapphire-GaN-based planar integrated free-space optical system Hofmann, M. (Institute of Micro- and Nanotechnologies, Optical Engineering, Technical University Ilmenau); HauguthFrank, S.; Lebedev, V.; Ambacher, O.; Sinzinger, S. Source: Applied Optics, v 47, n 16, Jun 1, 2008, p 2950-2955 ISSN: 0003-6935 CODEN: APOPAI Publisher: Optical Society of America Abstract: We report on the design and fabrication of a planar integrated free-space optical system working on the basis of binary phase diffractive optical elements (DOEs) realized in GaN on a sapphire substrate. Group III-nitride/sapphire substrates enable the parallel monolithic integration of passive microoptical elements like lenses and gratings as demonstrated here and optoelectronic devices like light emitters and photodetectors on a single wafer. We present an approach for the simultaneous optimization of the efficiency of transmissive and reflective diffractive optical elements processed in a single lithographic etching step. © 2008 Optical Society of America. (23 refs.) 162. Power and spectral efficient free space optical link based on MIMO system Sandhu, Harinder (Department of Electrical Engineering, Indian Institute of Technology Delhi); Chadha, D. Source: Proceedings of the 6th Annual Communication Networks and Services Research Conference, CNSR 2008, Proceedings of the 6th Annual Communication Networks and Services Research Coference, CNSR 2008, 2008, p 504-509 Conference: 6th Annual Communication Networks and Services Research Conference, CNSR 2008, May 5-8 2008, Halifax, NS, Canada Publisher: Institute of Electrical and Electronics Engineers Computer Society Abstract: In this paper, we describe a terrestrial, line-of-sight free space optical (FSO) communication link using nonrepetitive MIMO scheme with power efficient pulse position modulated (PPM) signal over highly scattering propagation medium described by Gamma-Gamma PDF channel. Due to its underlying low complexity, VBLASTZF (Vertical Bell Labs Layered Space Time - Zero Forcing) detection mechanism is exploited at the receiver side to increase overall spectral efficiency and channel capacity. Burst mode communication is assumed as the channel variations are considered to be constant within a block period and vary from block to block. Overall performance 最新文献报导 41 XIOPM latest Documents Report comparison under different turbulence conditions is obtained in terms of symbol error in a simulated random gammagamma PDF propagation environment. No coding has been included in the present work. © 2008 IEEE. (13 refs.) 163. Nonlinear state-space model of semiconductor optical amplifiers with gain compression for system design and analysis Kuntze, Scott B. (Department of Electrical and Computer Engineering, University of Toronto); Zilkie, Aaron J.; Pavel, Lacra; Aitchison, J. Stewart Source: Journal of Lightwave Technology, v 26, n 14, Jul 15, 2008, p 2274-2281 ISSN: 0733-8724 CODEN: JLTEDG Publisher: Institute of Electrical and Electronics Engineers Inc. Abstract: In this paper, we derive a new analytical state-space model for semiconductor optical amplifier (SOA) dynamics with nonlinear gain compression. We show that a multichannel closed-form state-space model is possible with polynomial gain compression and position-independent carrier density. The compressed model is significantly more accurate than existing noncompressed models as demonstrated by comparison with pump-probe experiments: response magnitude and recovery time are more accurately modeled with explicit gain compression. We then apply the model to design an optical feedback controller that regulates the total optical power at the output of a gain-compressed SOA. © 2008 IEEE. (29 refs.) 164. Minimum image entropy technology applied to the real-time autofocusing system of space optical remote sensors Guo, Linghua (Dept. of R and D, China Academy of Space Technology (CAST)); Li, Jianquan; Li, Yi; Wang, Sen; Jiang, Aimin; Ding, Xiaoqing; Peng, Ronggang; Juan, Hu Source: Proceedings of SPIE - The International Society for Optical Engineering, v 7000, Optical and Digital Image Processing, 2008, p 700011 ISSN: 0277-786X CODEN: PSISDG Conference: Optical and Digital Image Processing, Apr 7-9 2008, Strasbourg, France Sponsor: SPIE Europe;Alsace International;Conseil General du Bas-Rhin;Region Alsace;Communaute Urbaine de Strasbourg Publisher: SPIE Abstract: For space remote sensors with high resolution, large caliber, and long focal length, in-orbit automatic focusing technique is a significant application technology. Minimum image entropy (MIE) technology applied to real-time autofocusing system of space optical remote sensor possesses creativity and engineering significance. MIE's theoretical analysis, algorithm's computer simulation, and "Experimental Optical System" experiment have successfully validated MIE's validity as the criterion for optical remote sensor's auto-focusing. Related data indicate that for a diffractionlimited optical system with the f-ratio of F# = 39, the detecting sensitivity for checking-focus can be better than 0.1 mm, by means of MIE. (15 refs.) 165. Contamination effects of oil paint on the space optical system Lu, Chun-Lian (School of Astronautics, Harbin Institution of Technology); Zhou, Yan-Ping; Sang, Yi Source: Proceedings of SPIE - The International Society for Optical Engineering, v 6624, International Symposium on Photoelectronic Detection and Imaging 2007: Optoelectronic System Design, Manufacturing, and Testing, 2008, p 662421 ISSN: 0277-786X CODEN: PSISDG Conference: International Symposium on Photoelectronic Detection and Imaging, ISPDI 2007: Optoelectronic System Design, Manufacturing, and Testings, Sep 9-12 2007, Beijing, China Sponsor: China Ordnance Society;Beijing Institute of Technology Publisher: SPIE Abstract: Space environment in which the space optical system exposed includes space vacuum, cryogenics, and energetic particles and etc. The contamination effects on the space optical system, so the optical damage occurs. And the image quality of the system will be affected. In this paper, the effects of contamination to optical system were discussed, and the contamination source and its space distribution were analyzed. An experiment was designed to determine the effect value. Numeral fitting method was used to analyze the relationship of the optical damage factor (Transmissivity decay factor) and the contamination degree of the optical system. In the experiment, the contamination degree was expressed by mass thickness with the unit μg/mm2. Oil paint was used as the contamination source. Comparison between previous and present researches was given. (5 refs.) 166. Research of the application of low-precision large aperture nonimaging optics in free-space optical communication system 最新文献报导 42 XIOPM latest Documents Report Wang, Jia (Beijing Institute of Graphic Communication); Yu, Xin Source: Proceedings of SPIE - The International Society for Optical Engineering, v 6624, International Symposium on Photoelectronic Detection and Imaging 2007: Optoelectronic System Design, Manufacturing, and Testing, 2008, p 66240U ISSN: 0277-786X CODEN: PSISDG Conference: International Symposium on Photoelectronic Detection and Imaging, ISPDI 2007: Optoelectronic System Design, Manufacturing, and Testings, Sep 9-12 2007, Beijing, China Sponsor: China Ordnance Society;Beijing Institute of Technology Publisher: SPIE Abstract: A novel receiving antenna using low precision large aperture nonimaging optical apparatus in free-space optical (FSO) communication system has been proposed. The receiving optical antenna of FSO communication system is usually a conventional imaging optical system such as Newton system, Green system or Cassegrain system. It is ineffective to use a large aperture receiving antenna in FSO communication system because the precision imaging optical apparatus will be very expensive with aperture increase, so that, in order to reduce the difficulty of pointing and tracking between transmitter and receiver, the beam divergence has to be increased with the cost of lost part of the transmitted power. Since in the field of FSO communication system, the receiving optical antenna is used not to image but to concentrate optical signal as much as possible, the novel concept of using low precision large aperture nonimaging optical apparatus as receiving optical antenna to replace the conventional imaging optical system was proposed. Several nonimaging apparatus including spherical reflector, elliptical reflector, compound parabolic concentrator (CPC) and conical barrel concentrator are analyzed by ray tracing. Their gain and the transmission rate limitation due to wave-front aberrations are discussed, and their merit used in FSO communication system has been proved. (4 refs.) 167. Principles of free-space optical microelectromechanical systems Syms, R.R.A. (Optical and Semiconductor Devices Group, EEE Department, Imperial College London) Source: Proceedings of the Institution of Mechanical Engineers, Part C: Journal of Mechanical Engineering Science, v 222, n 1, January, 2008, p 1-17 ISSN: 0954-4062 CODEN: PMCSED Publisher: Professional Engineering Publishing Abstract: Optical microelectromechanical systems (MEMS) combine miniature optical components with precision fixtures, elastic suspensions, and microactuators, and allow complex functionality at low cost. However, the effect of the bounded nature of the beams propagating through the system on design is profound. The current paper reviews the fundamental consequences. Using a Gaussian beam formulation, models of guided modes in gradient index media, bounded beams and imaging components are constructed. Propagation algorithms are described. The alignment tolerances for common component trains such as fibre-to-fibre and beam-to-fibre connections are derived, limits on the curvature of reflecting surfaces are established, the scaling laws of free-space optical MEMS are presented and the effect of beam size on filter performance is clarified. Examples such as variable optical attenuators, optical crossconnect switches, filters and tunable lasers are discussed. © IMechE 2008. (80 refs.) 168. Diversity gain analysis of free-space optical communication systems Safari, Majid (Department of Electrical and Computer Engineering, University of Waterloo); Uysal, Murat Source: Canadian Conference on Electrical and Computer Engineering, IEEE Canadian Conference on Electrical and Computer Engineering, Proceedings, CCECE 2008, 2008, p 1239-1244 ISSN: 0840-7789 CODEN: CCCEFV Conference: IEEE Canadian Conference on Electrical and Computer Engineering, CCECE 2008, May 4-7 2008, Niagara Falls, ON, Canada Publisher: Institute of Electrical and Electronics Engineers Inc. Abstract: In this paper, we present a diversity gain analysis for free-space optical (FSO) diversity systems operating in log-normal atmospheric turbulence channels. We consider a multi-input multi-output (MIMO) system and two decodeand-forward (DF) relay-assisted systems based on either serial (i.e., multi-hop transmission) or parallel (i.e., cooperative diversity) configurations. We adopt the recently introduced so-called "asymptotical relative diversity order" (ARDO) in our analysis and derive ARDOs for FSO diversity systems under consideration. Assuming M transmit and N receive apertures in MIMO scheme, we demonstrate that an ARDO of 4σ2x/ln(1 + (exp(4σ2x)-1)/MN) is achievable where σ2x is the variance of the fading logamplitude. For weak turbulence conditions (i.e., σx [similar to] 0.1), ARDO is well approximated as MN. For DF relaying schemes with K relays each of which is equipped with single transmit/receive apertures, we demonstrate that ARDOs of (K + 1)11/6 and 211/6 K are achievable, respectively, for serial and parallel relaying configurations. © 2008 IEEE. (12 refs.) 最新文献报导 43 XIOPM latest Documents Report 169. Cross layer design for orthogonal space time block coded optical MIMO systems Zaidi, Syed Ali Raza (NUST School of Electrical Engineering and Computer Sciences, National University of Science and Technology); Hafeez, Maryam Source: 5th IEEE and IFIP International Conference on Wireless and Optical Communications Networks, WOCN 2008, 5th IEEE and IFIP International Conference on Wireless and Optical Communications Networks, WOCN 2008, 2008, p 4542497 Conference: 5th IEEE and IFIP International Conference on Wireless and Optical Communications Networks, WOCN 2008, May 5-7 2008, Surabaya, Indonesia Publisher: Institute of Electrical and Electronics Engineers Computer Society Abstract: Wireless infrared and free space optic communication are very strong candidates for next generation indoor wireless networks. Infrared diffuse communication provides high speed data transmission which is more economic then traditional fiber optic systems. Moreover it provides greater security than its counter part, i.e. radio frequency wireless communication, mainly due to its confined illumination. However the infrared wireless communication is not employed due to power limitations, alignment problems and performance degradation under severe weather conditions. In such conditions MIMO based signal processing techniques derived on parallels from wireless communication can be employed to provide better performance. In this paper we present a novel design for more reliable transmission. The proposed design is base on rate 1/2 Orthogonal Coding Scheme in combination with Virtual Fragmentation. Furthermore we discuss the cross layer architecture where by channel knowledge can be exploited by upper layers in order to efficiently decode the data, hence adapting to the channel conditions. ©2008 IEEE. (10 refs.) 170. Performance bounds for free-space optical MIMO systems with APD receivers in atmospheric turbulence Cvijetic, Neda (Charles L. Brown Department of Electrical and Computer Engineering, University of Virginia); Wilson, Stephen G.; Brandt-Pearce, Maite Source: IEEE Journal on Selected Areas in Communications, v 26, n 3, April, 2008, p 3-11 ISSN: 0733-8716 CODEN: ISACEM Publisher: Institute of Electrical and Electronics Engineers Inc. Abstract: Performance bounds of free space optical (FSO) systems with multiple laser transmitters and multiple avalanche photodetectors (APDs) are evaluated for terrestrial, line-ofsight communication. Specifically, analytical upper bounds on average uncoded error rate in turbulent multiple-input multipleoutput (MIMO) channels with Q-ary pulse position modulation (PPM) are derived for arbitrary observable densities, and are used to quantify APD-based performance improvements over pin detector arrays in non-fading, lognormal, and negative exponential channels. Moreover, it is shown that despite the high complexity of APD array statistics, these performance gains can be accurately predicted using a jointly-Gaussian model for APD array outputs. Both maximum likelihood (ML) and suboptimal combining rules are derived, and a simple equal gain combiner (EGC) that performs close to optimum is demonstrated. Finally, APD gain selection is discussed. © 2008 IEEE. (34 refs.) 171. Analysis on effect factors of ground-based electro-optic system detection ability on space object Zhang, Jihua; Yao, Dongsheng; Tan, Bin Source: Guangxue Xuebao/Acta Optica Sinica, v 28, n 6, June, 2008, p 11781182 Language: Chinese ISSN: 0253-2239 CODEN: GUXUDC Publisher: Chinese Optical Society Abstract: The detection ability of an electro-optic system is related to sky luminance, the electro-optic (EO) system and detector. The primary specification for expressing detection ability is signal-to-noise ratio. Based on analysis of the effect factors, a calculation formula of detection ability, including the imaging number, is derived. The influence of the sky luminance, parameters of the EO system, and the dispersion of the object on the detection ability is mainly analyzed. Simulation is conducted through an example according to the space object model, and the theoretical results show that the space-object can be detected when elevation is greater than 30°. Theoretical results fit with the experimental research. The effects of sky luminance, parameters of system, dispersion of imaging point on detection ability under different conditions are quantitatively learned. Moreover, the scientific basis for the optimization design of the system and development of practical work is provided. (11 refs.) 172. Design and evaluation of optical antenna module suitable for Radio-on Free-Space Optics link system for ubiquitous wireless Takahashi, Koichi (Olympus Opt-technology Co., ltd.); Higashino, Takeshi; Nakamura, Takuya; Aburakawa, Yuji; Tsukamoto, Katsutoshi; Komaki, Shozo; Wakamori, Kazuhiko; Suzuki, Toshiji; Kazaura, Kamugisha; Shah, Alam 最新文献报导 44 XIOPM latest Documents Report Mohammad; Omae, Kazunori; Matsumoto, Mitsuji; Miyamoto, Yuichi Source: Proceedings of SPIE - The International Society for Optical Engineering, v 6877, Free-Space Laser Communication Technologies XX, 2008, p 68770H ISSN: 0277-786X CODEN: PSISDG Conference: Free-Space Laser Communication Technologies XX, Jan 24 2008, San Jose, CA, United States Sponsor: Society of Photo-Optical Instrumentation Engineers (SPIE) Publisher: SPIE Abstract: We present initial results on research and development of an optical antenna module suitable for Radio-on Free-Space Optics (RoFSO) links. This new optical communication system is envisaged to be an effective means of realizing a ubiquitous society and therefore eliminating the digital divide. The RoFSO system is a trial system applying Radio on Fiber (RoF) technology for transmission through free space. Based on the results of research of next generation high-speed free-space optical communication system conducted in the past two years at Waseda University, we have developed an optical antenna module with efficient laser receiving characteristics as well as simple adjustment. The tracking system adopts two phases including rough tracking by the beacon light at 0.85 μm wavelength and fine tracking using communication light at 1.55 μm wavelength to improve compensation precision for the atmospheric turbulence at the time of beam propagation. We present results on the evaluation of performance characteristics (static characteristics) of the separate functions for RoFSO antenna module we have developed and confirmed the coupling efficiency and fine tracking characteristics which were set as goals at the beginning. (18 refs.) 173. Optimal scanning function for capturing segmented mirror in space optics system Zhang, Xiaofang (Department of Photo-Electronic Engineering, Beijing Institute of Technology); Yu, Xin; Wang, Xia; Liu, Jiaguo; Yang, Kui Source: Proceedings of SPIE - The International Society for Optical Engineering, v 6622, International Symposium on Photoelectronic Detection and Imaging 2007 - Laser, Ultraviolet, and Terahertz Technology, 2008, p 662214 ISSN: 0277-786X CODEN: PSISDG Conference: International Symposium on Photoelectronic Detection and Imaging 2007 - Laser, Ultraviolet, and Terahertz Technology, Sep 9-12 2007, Beijing, China Sponsor: China Ordnance Society;Beijing Institute of Technology Publisher: SPIE Abstract: A great deal segmented mirror errors consisting of piston and tip-tilt exist when space large aperture segmented optics system deploys. These errors will result in the departure of segmented mirrors images from the view. For that, proper scanning function should be adopted to control actuators rotating the segmented mirror, so that the images of segmented mirror can be put into the view and placed in the ideal position. The key of capturing segmented mirror images is selecting an optimal scanning function. This paper put forward the optimal scanning function principle based on capturing images by the fastest velocity. The scanning functions, such as screw-type, rose-type, and helianthus-type and so on, have their own merits and demerits. In my paper, the scanning functions above will be analyzed and discussed. As a sample, a simulation experiment is carried to study the effects of different scanning functions on three mirror astigmatism system, whose primary mirror with six segmented mirror. In simulation experiment, the piston and tip-tilt errors scale and the ideal position of segmented mirror are given, three scanning functions above are used to realize the capture process by utilizing the improved optics design software ZEMAX, the relationship between scanning functions and optical system are analyzed and the optimal one is determined. (6 refs.) 174. Evaluation of coverage area for a wide line-of-sight indoor optical free-space communication system employing coherent detection Jafar, M. (Department of Electronic and Electrical Engineering, University of Bath); O'Brien, D.C.; Stevens, C.J.; Edwards, D.J. Source: IET Communications, v 2, n 1, , 2008, p 18-26 ISSN: 1751-8628 Publisher: Institution of Engineering and Technology Abstract: The application of coherent detection to indoor optical free-space communications is considered here. Analytical expressions are derived for a wide line-of-sight (W-LOS) optical link which determine the coverage area and the required photo-detection area given different binary digital transmission schemes and a given bit rate. The coverage area is maximised for systems using both metal-semiconductor-metal (MSM) and PIN photo-detectors. Results show that MSM photo-detectors, due to their inherently lower capacitance per unit photo-detection area, result in a greater coverage area than their PIN counterparts. To demonstrate the viability of implementing coherent detection indoors, a 200Mb/s LOS optical link which uses coherent detection is also reported. © The Institution of Engineering and Technology 2008. (29 refs.) 最新文献报导 45 XIOPM latest Documents Report 175. Development of a nanoscale directionally sensitive optical radiation sensor for guidance and control of nanorobotic space exploration systems-the VCELL Cook, Koy B. (Department of Electrical Engineering, Alabama A and M University); Watson, Michael D. Source: Conference Proceedings - IEEE SOUTHEASTCON, IEEE SoutheastCon 2008, 2008, p 415-420 ISSN: 0734-7502 CODEN: CPISDM Conference: IEEE SoutheastCon 2008, Apr 3-6 2008, Huntsville, AL, United States Sponsor: IEEE Huntsville Section;IEEE Region 3 Publisher: Institute of Electrical and Electronics Engineers Inc. Abstract: This paper will report on efforts to develop an enabling nanotechnology compatible directionally sensitive optical radiation sensor (VCELL) prototype. The proposed sensor is a novel silicon optical sensor that is directionally sensitive to incident light without the usual necessity of requiring mechanical assemblies for directing impinging radiation. The VCELL can be integrated into the front end of a single nanochip guidance system for future space exploration systems requiring extremely small size (mass constrained and power constrained) such as small robots, picosatellites and sensor networks, etc. The VCELL will enable a low cost miniature optical sensor for future MSFC Mission Area applications. Among these are a Sun pointer for MARS satellites, landers and rovers and various other scientific spacecraft such as small communications satellites, remote sensing satellites, sun sensors for rovers for daylight directional navigation. ©2008 IEEE. (10 refs.) 176. Notes on use of strict optical orthogonal codes to design unequal channel spacing (UCS) frequency sequences for DWDM systems with reduced FWM crosstalk Zhang, Jian-Guo (Department of Electrical, Computer and Communications Engineering, Faculty of Engineering, Science and the Built Environment); Sharma, A.B. Source: Optics Communications, v 281, n 22, Nov 15, 2008, p 55745579 ISSN: 0030-4018 CODEN: OPCOB8 Publisher: Elsevier Abstract: A paper [E. Mutafungwa et al., Optics Communications 198 (4) (2001) 339] reported the use of strict optical orthogonal codes (S-OOC's) to reduce the four-wave mixing (FWM) crosstalk in dense wavelength-division multiplexing (DWDM) systems by using our S-OOC based unequal channel spacing (UCS) scheme and our special frequency sequences constructed, without referring to the original work. Some mistakes and inaccuracies are identified in the published paper regarding interpretation of S-OOC and its associated UCS scheme, which can cause the confusion of understanding the key concepts and principle about the S-OOC based UCS scheme. As a result, in this paper we present the necessary corrections and notes which deal with the major expressions and key concepts of both SOOC's and our proposed scheme. In doing so, the mapping of a S-OOC sequence to the UCS frequency set is appropriately interpreted, and the characteristics of S-OOC based UCS schemes are described. Moreover, the correct evaluation of optical bandwidths is presented for DWDM systems using S-OOC based UCS schemes, and the comparison of the repeated-codeword assignments with the overlapping-codeword assignments is also carried out. Furthermore, we discuss the effect of fractional-slot occupation for frequency assignments on the bandwidth expansion of UCS-DWDM systems. These in turn can lead to correctly understanding the principles of S-OOC based UCS schemes and applying them to assign the UCS frequencies to DWDM systems for the reduction of FWM crosstalk. © 2008 Elsevier B.V. All rights reserved. (15 refs.) Imaging Spectrometry 177 Author(s): Donohue, SR (Donohue, Sean R.); Krushinski, JH (Krushinski, Joseph H.); Pike, VW (Pike, Victor W.); Chernet, E (Chernet, Eyassu); Phebus, L (Phebus, Lee); Chesterfield, AK (Chesterfield, Amy K.); Felder, CC (Felder, Christian C.); Halldin, C (Halldin, Christer); Schaus, JM (Schaus, John M.) Title: Synthesis, ex vivo evaluation, and radiolabeling of potent 1,5-diphenylpyrrolidin-2-one cannabinoid subtype-1 receptor ligands as candidates for in vivo imaging Source: JOURNAL OF MEDICINAL CHEMISTRY, 51 (18): 5833-5842 SEP 25 2008 Abstract: We have reported that [methyl-C-11] (3R,5R)-5-(3-methoxyphenyl)-3-[(R)-1-phenylethylamino]-1-(4trifluoromethylphenyl)pyrrolidin-2-one ([C-11]8, [C-11]MePPEP) binds with high selectivity to cannabinoid type-l (CB1) receptors in monkey brain in vivo. We now describe the synthesis of 8 and four analogues, namely, the 4fluorophenyl (16, FMePPEP), 3-fluoromethoxy (20, FMPEP), 3-fluoromethoxy-d(2) (21, FMPEP-d(2)), and 3- 最新文献报导 46 XIOPM latest Documents Report fluoroethoxy analogues (22, FEPEP), and report their activity in an ex vivo model designed to identify compounds suitable for use as positron emission tomography (PET) ligands. These ligands exhibited high, selective potency at CB I receptors in vitro (K-b < 1 nM). Each ligand (30 mu g/kg, iv) was injected into rats under baseline and pretreatment conditions (3, rimonabant, 10 mg/kg, iv) and quantified at later times in frontal cortex ex vivo with liquid chromatography-mass spectrometry (LC-MS) detection. Maximal ligand uptakes were high (22.6-48.0 ng/g). Under pretreatment, maximal brain uptakes were greatly reduced (6.5 - 17.3 ng/g). Since each ligand readily entered brain and bound with high selectivity to CB 1 receptors, we then established and here describe methods for producing [C-11]8, [C-11] 16, and [[F-18]20-22 in adequate activities for evaluation as candidate PET radioligands in vivo. -------------------------------------------------------------------------------178 Author(s): Luykx, DMAM (Luykx, Dion M. A. M.); Peters, RJB (Peters, Ruud J. B.); van Ruth, SM (van Ruth, Saskia M.); Bouwmeester, H (Bouwmeester, Hans) Title: A review of analytical methods for the identification and characterization of nano delivery systems in food Source: JOURNAL OF AGRICULTURAL AND FOOD CHEMISTRY, 56 (18): 8231-8247 SEP 24 2008 Abstract: Detection and characterization of nano delivery systems is an essential part of understanding the benefits as well as the potential toxicity of these systems in food. This review gives a detailed description of food nano delivery systems based on lipids, proteins, and/or polysaccharides and investigates the current analytical techniques that can be used for the identification and characterization of these delivery systems in food products. The analytical approaches have been subdivided into three groups; separation techniques, imaging techniques, and characterization techniques. The principles of the techniques together with their advantages and drawbacks, and reported applications concerning nano delivery systems, or otherwise related compounds are discussed. The review shows that for a sufficient characterization, the nano delivery systems need to be separated from the food matrix, for which high-performance liquid chromatography or field flow fractionation are the most promising techniques. Subsequently, online photon correlation spectroscopy and mass spectrometry seem to be a convenient combination of techniques to characterize a wide variety of nano delivery systems. -------------------------------------------------------------------------------179 Author(s): Pei, L (Pei, Lirong); Duscher, G (Duscher, Gerd); Steen, C (Steen, Christian); Pichler, P (Pichler, Peter); Ssel, HR (Ssel, Heiner R.); Napolitani, E (Napolitani, Enrico); De Salvador, D (De Salvador, Davide); Piro, AM (Piro, Alberto Maria); Terrasi, AT (Terrasi, A. Tonio); Severac, F (Severac, Fabrice); Cristiano, F (Cristiano, Filadelfo); Ravichandran, K (Ravichandran, Karthik); Gupta, N (Gupta, Naveen); Windl, W (Windl, Wolfgang) Title: Detailed arsenic concentration profiles at Si/SiO2 interfaces - art. no. 043507 Source: JOURNAL OF APPLIED PHYSICS, 104 (4): 43507-43507 AUG 15 2008 Abstract: The pile-up of arsenic at the Si/SiO2 interface after As implantation and annealing was investigated by high resolution Z-contrast imaging, electron energy-loss spectroscopy (EELS), grazing incidence x-ray fluorescence spectroscopy (GIXRF), secondary ion mass spectrometry, x-ray photoelectron spectroscopy, Rutherford backscattering spectrometry, as well as Hall mobility and four-point probe resistivity measurements. After properly taking into account their respective artifacts, the results of all methods are compatible with each other, with EELS and GI-XRF combined with etching providing similar spatial resolution on the nanometer scale for the dopant profile. The sheet concentration of the piledup As at the interface was found to be similar to 1 x 10(15) cm(-2) for an implanted dose of I X 1016 cm-2 with a maximum concentration of similar to 10 at. %. The strain observed in the Z-contrast images also suggests a significant concentration of local distortions within 3 nm from the interface, which, however, do not seem to involve intrinsic point defects. (C) 2008 American Institute of Physics. -------------------------------------------------------------------------------180 Author(s): Borch, T (Borch, Thomas); Camper, AK (Camper, Anne K.); Biederman, JA (Biederman, Joel A.); Butterfield, PW (Butterfield, Phillip W.); Gerlach, R (Gerlach, Robin); Amonette, JE (Amonette, James E.) Title: Evaluation of characterization techniques for iron pipe corrosion products and iron oxide thin films Source: JOURNAL OF ENVIRONMENTAL ENGINEERING-ASCE, 134 (10): 835-844 OCT 2008 Abstract: A common problem faced by drinking water studies is that of properly characterizing the corrosion products (CP) in iron pipes or synthetic Fe (hydr)oxides used to simulate the iron pipe used in municipal drinking-water systems. The present work compares the relative applicability of a suite of imaging and analytical techniques for the characterization of CPs and synthetic Fe oxide thin films and provide an overview of the type of data that each instrument can provide as well as their limitations to help researchers and consultants choose the best technique for a given task. Crushed CP from a water distribution system and synthetic Fe oxide thin films formed on glass surfaces were chosen as test samples for this evaluation. The CP and synthetic Fe oxide thin films were analyzed by atomic force microscopy (AFM), scanning 最新文献报导 47 XIOPM latest Documents Report electron microscopy (SEM), energy-dispersive spectroscopy, time-of-flight secondary ion mass spectrometry (ToFSIMS), X-ray powder diffractometry (XRD), grazing incident diffractometry (GID), transmission electron microscopy (TEM), selected area electron diffraction, X-ray photoelectron spectroscopy (XPS), Fourier transform infrared, Mossbauer spectroscopy, Brunauer-Emmett-Teller N-2 adsorption and Fe concentration was determined by the ferrozine method. XRD and GID were found to be the most suitable techniques for identification of the mineralogical composition of CP and synthetic Fe oxide thin films, respectively. AFM and a combined ToF-SIMS-AFM approach proved excellent for roughness and depth profiling analysis of synthetic Fe oxide thin films, respectively. Corrosion products were difficult to study by AFM due to their surface roughness, while synthetic Fe oxide thin films resisted most spectroscopic methods due to their limited thickness (118 nm). XPS analysis is not recommended for mixtures of Fe (hydr)oxides due to their spectral similarities. SEM and TEM provided great detail on mineralogical morphology. -------------------------------------------------------------------------------181 Author(s): Kikkawa, J (Kikkawa, J.); Akita, T (Akita, T.); Tabuchi, M (Tabuchi, M.); Shikano, M (Shikano, M.); Tatsumi, K (Tatsumi, K.); Kohyama, M (Kohyama, M.) Title: Real-space observation of Li extraction/insertion in Li1.2Mn0.4Fe0.4O2 positive electrode material for Liion batteries Source: ELECTROCHEMICAL AND SOLID STATE LETTERS, 11 (11): A183-A186 2008 Abstract: Using a spectrum-imaging scheme based on scanning transmission electron microscopy electron energy-loss spectroscopy, we achieve real-space observation of the extraction and insertion behaviors of Li ions in a high-capacity positive electrode material, Li1.2Mn0.4Fe0.4O2 (Li2MnO3-LiFeO2 system), consisting of Fe- and Mn-rich nanodomains. The Li ions are first extracted from Fe-rich nanodomains and subsequently extracted from the whole region. After discharge, Li ion recovery occurs. Results indicate the role of nanodomain structures in activating both alpha-LiFeO2 and Li2MnO3, which are each inactive as pure bulk. We discuss mechanisms of high capacity and degradation associated with oxidation of the oxygen ions. (C) 2008 The Electrochemical Society. -------------------------------------------------------------------------------182 Author(s): Peng, IX (Peng, Ivory X.); Loo, RRO (Loo, Rachel R. Ogorzalek); Shiea, J (Shiea, Jentaie); Loo, JA (Loo, Joseph A.) Title: Reactive-electrospray-assisted laser desorption/ionization for characterization of peptides and proteins Source: ANALYTICAL CHEMISTRY, 80 (18): 6995-7003 SEP 15 2008 Abstract: Electrospray-assisted laser desorption/ionization (ELDI) is a soft ionization method for mass spectrometry (MS) and combines features of both electrospray ionization (ESI) and matrix-assisted laser desorption/ionization to generate ESIlike multiply charged molecules. The ELDI process is based on merging ESI-generated, charged droplets with particles UV laser desorbed from dried or wet sample deposits. We previously reported that ELDI is amenable for MS-based protein identification of large peptides and small proteins using top-down and bottom-up techniques (Peng, I.X.; Shiea, J.; Ogorzalek Loo, R. R.; Loo, J. A. Rapid Commun. Mass Spectrom. 2007, 21, 2541-2546). We have extended our studies by applying collisionally activated dissociation and electron-transfer dissociation MS' to protein analysis and show that ELDI is capable of multistage MS to MS4 for top-down characterization of large proteins such as 29 kDa carbonic anhydrase. Multiply charged proteins generated by the ELDI mechanism can be shifted to higher charge by increasing the organic content in the ESI solvent to denature the protein molecules, or by adding m-nitrobenzyl alcohol to the ESI solvent. Furthermore, we introduce "reactive-ELDI", which supports chemical reactions during the ELDI process. Preliminary data for online disulfide bond reduction using dithiothreitol on oxidized glutathione and insulin show reactive-ELDI to be effective. These data provide evidence that the laser-desorbed particles merge with the ESIgenerated charge droplets to effect chemical reactions prior to online MS detection. This capability should allow other chemical and enzymatic reactions to be exploited as online protein characterization tools, as well as extending them to flexible, spatially resolved tissue screening and imaging. Also, these reactive-ELDI disulfide reduction experiments enable direct top-down protein identification for proteomic study, side stepping laborious, time-consuming sample preparation steps such as in-solution reduction and alkylation. -------------------------------------------------------------------------------183 Author(s): Cherukuri, S (Cherukuri, Srujana); Hock, R (Hock, Robert); Ueda, T (Ueda, Tetsuya); Catez, F (Catez, Frederic); Rochman, M (Rochman, Mark); Bustin, M (Bustin, Michael) Title: Cell cycle-dependent binding of HMGN proteins to chromatin Source: MOLECULAR BIOLOGY OF THE CELL, 19 (5): 1816-1824 MAY 2008 Abstract: Throughout the cell cycle, the histones remain associated with DNA, but the repertoire of proteins associated with the chromatin fiber continuously changes. The chromatin interaction of HMGNs, a family of nucleosome binding proteins 最新文献报导 48 XIOPM latest Documents Report that modulates the structure and activity of chromatin, during the cell cycle is controversial. Immunofluorescence studies demonstrated that HMGNs are not associated with chromatin, whereas live cell imaging indicated that they are present in mitotic chromosomes. To resolve this controversy, we examined the organization of wild-type and mutated HMGN1 and HMGN2 proteins in the cell nucleus by using immunofluorescence studies, live cell imaging, gel mobility shift assays, and bimolecular fluorescence complementation (BiFC). We find that during interphase, HMGNs bind specifically to nucleosomes and form homodimeric complexes that yield distinct BiFC signals. In metaphase, the nucleosomal binding domain of the protein is inactivated, and the proteins associate with chromatin with low affinity as monomers, and they do not form specific complexes. Our studies demonstrate that the mode of binding of HMGNs to chromatin is cell cycle dependent. -------------------------------------------------------------------------------184 Author(s): Winesett, DA (Winesett, Donald A.); Tsou, AH (Tsou, Andy H.) Title: The application of high resolution chemical imaging techniques for butyl rubber blends Source: RUBBER CHEMISTRY AND TECHNOLOGY, 81 (2): 265-275 MAY-JUN 2008 Abstract: Atomic Force Microscopy (AFM), Time-of-Flight Secondary Ion Mass Spectrometry (ToF-SIMS) imaging, and Scanning Transmission X-ray Microscopy (STXM) are applied to identical series of elastomeric blends to evaluate the relative strengths and weaknesses of each imaging technique. AFM is a high resolution, high contrast technique with straight forward sample preparation that derives contrast through elastic modulus variations, but, when used in a conventional mode, has limited chemical specificity. ToF-SIMS imaging can map phases, detect trace levels (ppm) of additives and other chemical species based on relatively straight forward sample preparation, but has poorer spatial resolution and the instrumentation is expensive. STXM has excellent chemical specificity and good spatial resolution but is only available at a beamline and requires more advanced sample preparation. Each technique will be overviewed briefly and relative merits of each will be compared based on evaluations of some commercially relevant rubber blend materials. -------------------------------------------------------------------------------185 Author(s): Wu, RW (Wu, Re-Wen); Wang, FS (Wang, Feng-Sheng); Ko, JY (Ko, Jih-Yang); Wang, CJ (Wang, Ching-Jen); Wu, SL (Wu, Shin-Long) Title: Comparative serum proteome expression of osteonecrosis of the femoral head in adults Source: BONE, 43 (3): 561-566 SEP 2008 Abstract: Osteonecrosis of the femoral head (ONFH) is a skeletal disorder characterized by ischemic deterioration, bone marrow edema and eventually femoral head collapse. The systemic regulation of ONFH in adult patients has not been examined. Serum proteomic is an innovative tool that potentially detects simultaneous expressions of serum Proteins in pathological contexts. We compared the serum proteome profiles of 11 adult patients with ONFH (3 females and 8 males) and 11 healthy volunteers (3 females and 8 males). The proteins in the aliquots of sera were Subjected to isoelectric focusing, two- dimensional gel electrophoresis and silver staining. The protein spots were matched and quantified using an imaging analysis system. The differentially expressed protein spots were subjected to in-gel trypsin digestion. The peptide mass fingerprints were identified by matrix-assisted laser desorption ionization time-of-flight mass spectrometry (MALDI-TOF/TOF) and a bioinformation search. We found that ONFH patients showed significantly higher abundances of kininogen 1 variant, complement factor C3 precursor, and complement factor H and lower levels of antithrombin III chain B, apolipoprotein A-IV precursor, and gelsolin isoform a precursor. These proteins of interest were reported to modulate thrombotic/fibrinolytic reactions, oxidative stress, vessel injury, tissue necrosis or cell apoptosis in several tissue types under pathological contexts. Taken together, the occurrence of ONFH was associated with various Serum protein expressions. Our high-throughtput serum proteomic findings indicated that multiple pathological reactions presumably occurred in ONFH. (C) 2008 Elsevier Inc. All rights reserved. -------------------------------------------------------------------------------186 Author(s): Brewer, LN (Brewer, Luke N.); Ohlhausen, JA (Ohlhausen, James A.); Kotula, PG (Kotula, Paul G.); Michael, JR (Michael, Joseph R.) Title: Forensic analysis of bioagents by X-ray and TOF-SIMS hyperspectral imaging Source: FORENSIC SCIENCE INTERNATIONAL, 179 (2-3): 98-106 AUG 6 2008 Abstract: Hyperspectral imaging combined with multivariate statistics is an approach to microanalysis that makes the maximum use of the large amount of data potentially collected in forensics analysis. This Study examines the efficacy of using hyperspectral imaging-enabled microscopies to identify chemical Signatures in simulated bioagent materials. This approach allowed for the ready discrimination between all samples in the test. In particular, the hyperspectral imaging approach allowed for the identification of particles with trace elements that Would have been missed with a traditional 最新文献报导 49 XIOPM latest Documents Report approach to forensic microanalysis. The importance of combining signals from multiple length scales and analytical sensitivities is discussed. Published by Elsevier Ireland Ltd. -------------------------------------------------------------------------------187 Author(s): Giron, MC (Giron, M. C.); Portolan, S (Portolan, S.); Bin, A (Bin, A.); Mazzi, U (Mazzi, U.); Cutler, CS (Cutler, C. S.) Title: Cytochrome P450 and radiopharmaceutical metabolism Source: QUARTERLY JOURNAL OF NUCLEAR MEDICINE AND MOLECULAR IMAGING, 52 (3): 254266 SEP 2008 Abstract: Positron emission tomography (PET) is a powerful non-invasive probe to investigate human physiology. A large number of radiotracers have been studied as imaging agents, but only a few have found clinical applications in phamacology. A potential radiopharmaceutical is designed with very specific physiochemical characteristics, but, generally, less attention is paid to its adsorption, distribution, metabolism, and excretion properties, especially metabolism. Understanding the metabolic fate of radiopharmaceutical probes is essential for an accurate analysis and interpretation of PET measurements. The inherent inability of PET to differentiate between a parent compound and its metabolites confounds the interpretation of images and may impact the identification of the pathologically induced biochemical changes under investigation. Cytochrome P450 plays a major role in mammalian xenobiotic biotransformation and many in vitro methods are available to study and predict drug metabolism. The purpose of this review is to highlight the existing in vitro techniques available to investigate the biotransformation of xenobiotics in a fashion analogous to small molecule drug discovery The aim is to facilitate the development and validation phases of PET tracers during preclinical evaluation. Emphasis is placed also on describing how cross species comparisons are essential in establishing appropriate translational pharmacology. Procedures of analysis (tandem liquid chromatographymass spectrometry), typically used for studying the metabolism of drugs, are proposed as quick and accurate tools for the determination of a radiopharmaceutical's metabolic stability at the tracer level. -------------------------------------------------------------------------------188 Author(s): Hac-Wydro, K (Hac-Wydro, Katarzyna); Dynarowicz-Latka, P (Dynarowicz-Latka, Patrycja) Title: The impact of sterol structure on the interactions with sphingomyelin in mixed Langmuir monolayers Source: JOURNAL OF PHYSICAL CHEMISTRY B, 112 (36): 11324-11332 SEP 11 2008 Abstract: In this work, the Langmuir monolayer technique was applied to study the interactions between sphingomyelin and various sterols differing in the Structure of the side chain (cholesterol, beta-sitosterol, stigmasterol). The mean area per molecule and the excess free energy of mixing values were analyzed in the context of sterol-induced condensing effect and interactions between molecules in the mixed monolayers. Moreover, the compression modulus Values were calculated and widely discussed from the point of view of the ordering effect of sterols. It was found that all of the sterols investigated form the most stable monolayers with sphingomyelin at 2: 1 sphingomyelin:sterol proportion and the strongest interactions exist between molecules in cholesterol-containing films. Moreover, cholesterol provokes the strongest area condensation and reveals the highest ordering properties, while plant sterols were found to differ only slightly with regards to their ordering properties. Additionally, the ordering effect of the sterols on dipalmitoylphosphatidylcholine (DPPC) films was analyzed and compared to that on sphingomyelin films. Tracking of The Moving Target 189. Moving target track detection of airborne SAR with three antennas Zhang, Xu-Jin (Dept. of Electronic Engineering, Nanjing Univ. of Aeronautics and Astronautics); Zhu, Zhao-Da; Deng, Hai-Tao; Zhang, Chang-Yao Source: Xi Tong Gong Cheng Yu Dian Zi Ji Shu/Systems Engineering and Electronics, v 30, n 3, March, 2008, p 466-469 Language: Chinese ISSN: 1001-506X CODEN: XGYDEM Publisher: Chinese Institute of Electronics Abstract: In military application, besides high resolution images, the SAR can also provide functions such as ground moving target detection, location and track. According to the characteristic of a SAR/MTI system with three antennas designed by ECRIEE, the channels equalizing technology and clutter suppression interferometry processing are applied to improve the clutter cancellation ability of the system. Computer simulation and real data processing results show that the proposed method is effective. (5 refs.) 最新文献报导 50 XIOPM latest Documents Report 190. Recognition and servo tracking of moving target based on image features Liu, Hongding (School of Automation Science and Electrical Engineering, Beihang University); Qin, Shiyin Source: Yi Qi Yi Biao Xue Bao/Chinese Journal of Scientific Instrument, v 29, n 3, March, 2008, p 644-648 Language: Chinese ISSN: 0254-3087 CODEN: YYXUDY Publisher: Science Press Abstract: In this paper, the research on the recognition and servo tracking of moving target for a wheeled moving robot with a monocular camera is carried out in a relatively complex background. At first the computer vision library from Intel, Open CV, was employed to implement image processing and feature extracting, then the shape of moving target was recognized and the visual servo tracking was achieved based on local features of image moments in noise condition. In order to improve the system performance, a curve-fitting model was built to predict the dynamic trend and characteristics. Experiment results indicate that the system can stably recognize a fast motional target and track it in real-time under noisy background and without precise camera calibration. (16 refs.) Database: Compendex 191. Estimation of radial velocity of moving targets by along-track interferometric SAR systems Budillon, Alessandra (Dipartimento per le Tecnologie, Universita di Napoli Parthenope, Centro Direzionale di Napoli); Pascazio, Vito; Schirinzi, Gilda Source: IEEE Geoscience and Remote Sensing Letters, v 5, n 3, July, 2008, p 349-353 ISSN: 1545-598X Publisher: Institute of Electrical and Electronics Engineers Inc. Abstract: Along-track interferometric synthetic aperture radar (AT-InSAR) can be used to estimate the radial velocity of ground moving targets, starting from interferometric phase measures. The estimation obtained from a single-phase interferogram suffers from ambiguities. To solve these problems, multichannel AT-InSAR systems are required. In this letter, we analyze the radial velocity maximum-likelihood estimation accuracy with respect to AT-InSAR system parameters, such as velocity values and different clutter and thermal noise levels. We consider two different models for the target response: a deterministic model and a zero-mean Gaussian model. The presented results show that AT-InSAR systems exhibit better estimation accuracies for low-velocity values (slow targets). © 2008 IEEE. (14 refs.) 192. Sequential along-track integration for early detection of moving targets Grossi, Emanuele (Dept. Automazione, Elettromagnetismo, Ingegneria dell'Informazione Matematica Industriale, Universita degli Studi di Cassino); Lops, Marco Source: IEEE Transactions on Signal Processing, v 56, n 8 II, August, 2008, p 3969-3982 ISSN: 1053-587X CODEN: ITPRED Publisher: Institute of Electrical and Electronics Engineers Inc. Abstract: This paper concerns the joint multiframe sequential target detection and track estimation in early-warning radar surveillance systems. The rationale for applying sequential procedures in such a scenario is that they promise a sensitivity increase of the sensor or, alternatively, a reduction in the time needed to take a decision. Unlike previous works on sequential radar detection, the attention is not restricted to stationary targets, namely position changes during the illumination period are allowed. Starting from previous sequential rules, different truncated sequential strategies are proposed and assessed: they are aimed at orienting the sensor resources towards either the detection or the track estimation or the position estimation. Bounds on the performances of the proposed procedures in terms of the system parameters are derived and computational complexity is examined. Also, numerical experiments are provided to elicit the interplay between sensor-target parameters and system performances, and to quantify the gain with respect to other fixed-sample-size procedures. © 2008 IEEE. (33 refs.) 193. Coordinated standoff tracking of moving targets using Lyapunov guidance vector fields Frew, Eric W. (University of Colorado); Lawrence, Dale A.; Morris, Steve Source: Journal of Guidance, Control, and Dynamics, v 31, n 2, March/April, 2008, p 290-306 ISSN: 0731-5090 CODEN: JGCODS Publisher: American Institute of Aeronautics and Astronautics Inc. Abstract: This paper presents a control structure for cooperative stand-offline-of-sight trackingofamoving targetbyateam of unmanned aircraft based on a Lyapunov guidance vector field that produces stable convergence to a circling limit cycle behavior. A guidance vector field is designed for a stationary target and then modified with a correction term that accounts for a moving target and constant background wind. Cooperative tracking by multiple unmanned aircraft is 最新文献报导 51 XIOPM latest Documents Report achieved through additional phasing, also with a Lyapunov stability analysis. Convoy protection, inwhich the unmanned aircraft must scout an area ahead of the moving target, is performed by extending the cooperative stand-off line-of-sight limit cycle attractor along the direction of travel. Simulation results demonstrate the behavior of the algorithms as well as the improvement that results from cooperation. Finally, simulations of a larger cooperative search, acquisition, and tracking scenario are described that illustrate the use of the cooperative standoff line-of-sight and convoy protection controllers in a realistic application. (30 refs.) 194. Tracking and locating algorithm of 3-dimensional moving targets using 2-dimensional angular measurements from multiple passive sensors Liu, Zhe (Systems Engineering Institute, Xi'an Jiaotong University); Wei, Junhu; Zhao, Jun; Yao, Dongsheng; Sun, Guoji Source: Hsi-An Chiao Tung Ta Hsueh/Journal of Xi'an Jiaotong University, v 42, n 4, April, 2008, p 462465+470 Language: Chinese ISSN: 0253-987X CODEN: HCTPDW Publisher: Xi'an Jiaotong University Abstract: The target motion analysis (TMA) is a nonlinear estimation problem because of the nonlinearity of its measure equation, and the pseudo linear equation derived from the measure equation will result in biased or divergent solutions. The authors present an efficient and nearly unbiased algorithm for biostatic bearings-only target locating based on measured angles. The simulation results show that compared with the extended Kalman filter, the error curve of the root mean square of the position estimated by the proposed algorithm approaches the Cramer-Rao low bound (CRLB) more efficiently for Gaussian noise, and the precision is approximately improved by 50%. (10 refs.) Ultraviolet Imaging\Detection 195. Back-illuminated ultraviolet image sensor in silicon-on-sapphire Joon, Hyuk Park (Electrical Engineering Department, Yale University); Culurciello, Eugenio Source: Proceedings IEEE International Symposium on Circuits and Systems, 2008 IEEE International Symposium on Circuits and Systems, ISCAS 2008, 2008, p 1854-1857 ISSN: 0271-4310 CODEN: PICSDI Conference: 2008 IEEE International Symposium on Circuits and Systems, ISCAS 2008, May 18-21 2008, Seattle, WA, United States Publisher: Institute of Electrical and Electronics Engineers Inc. Abstract: We present a back-illuminated 32 x 32 pixel SOI image sensor chip in 0.5-μm silicon-on-sapphire process capable of ultraviolet imaging. The imager performs "snap-shot" image acquisition and analog readout at a continuous rate of a thousand frames/s and consumes as little as 650 μW. Each pixel consists of a photodiode and a memory capacitor in 40 μm x 40 μm with a fill factor of 43%. The image sensor is suited for hyper-spectral imaging at high speeds. ©2008 IEEE. (9 refs.) 196. Analysis of extreme ultraviolet microscopy images of patterned nanostructures based on a correlation method Wachulak, P.W. (National Science Foundation Engineering Research Center, Extreme Ultraviolet Science and Technology, Colorado State University); Brewer, C.A.; Brizuela, F.; Menoni, C.S.; Chao, W.; Anderson, E.H.; Bartels, R.A.; Rocca, J.J.; Marconi, M.C. Source: Journal of the Optical Society of America B: Optical Physics, v 25, n 7, July, 2008, p B20-B26 ISSN: 0740-3224 CODEN: JOBPDE Publisher: Optical Society of America Abstract: A method to analyze extreme ultraviolet microscopy images of nanostructures that allows for the simultaneous determination of an object's feature size and image resolution is presented. It is based on the correlation between the image and a set of templates of known resolution generated from the original image using Gaussian filters. The analysis was applied to images obtained with a Fresnel zone plate microscope that uses a 13.2 nm wavelength laser light for illumination. The object's feature size and the resolution obtained with this method are shown to be in very good agreement with independent measurements of both magnitudes. © 2008 Optical Society of America. (18 refs.) 197. Research on mechanism and ultraviolet imaging of corona discharge of electric device faults 最新文献报导 52 XIOPM latest Documents Report Zang, Chunyan (College of Electrical and Electronics Engineering, Huazhong University of Sci. and Tech.); Xinjie, Zhao; Shuang, He; Lei, Hongcai; Zhenglong, Jiang; Huisheng, Ye; Zhiwen, Jiang Source: Conference Record of IEEE International Symposium on Electrical Insulation, 2008 IEEE International Symposium on Electrical Insulation, ISEI 2008, 2008, p 690-693 ISSN: 0164-2006 CODEN: CRIID6 Conference: 2008 IEEE International Symposium on Electrical Insulation, ISEI 2008, Jun 9-12 2008, Vancouver, BC, Canada Publisher: Institute of Electrical and Electronics Engineers Inc. Abstract: At present, the detection methods of electric device faults are often undertaken by infrared imaging system, ultrasonic imagining system, etc. However, these techniques have some inherited shortcomings. As to the high insulation level of an Ultra High Voltage system, the long distance from ground exists. Thus it needs a more effective detection technology for the safety of power system. This paper studies on the mechanism of UV light and corona discharge, recommends the maximum UV photon number as the important parameter to evaluate the serious degree of defects, extracts the UV spectrum characteristics of various typical faults of electric device, and discusses about the insufficient part of UV detection. The research results will help power system maintenance to develop on-line monitoring of power network and get an accurate defect point and type. ©2008 IEEE. (9 refs.) 198. Near-wavelength resolution extreme ultraviolet imaging with a desktop-size laser Brizuela, F. (NSF ERC for Extreme Ultraviolet Science and Technology, Department of Electrical and Computer Engineering, Colorado State University); Brewer, C.; Martz, D.; Marconi, M.C.; Rocca, J.J.; Menoni, C.S.; Chao, W.; Anderson, E.H.; Attwood, D.T.; Vinogradov, A.V.; Artioukov, I.A.; Ponomareko, A.G.; Kondratenko, V.V. Source: 2008 Conference on Quantum Electronics and Laser Science Conference on Lasers and Electro-Optics, CLEO/QELS, 2008 Conference on Quantum Electronics and Laser Science Conference on Lasers and Electro-Optics, CLEO/QELS, 2008, p 4551135 ISBN-10: 1557528594 Conference: Conference on Quantum Electronics and Laser Science Conference on Lasers and Electro-Optics, CLEO/QELS 2008, May 4-9 2008, San Jose, CA, United States Publisher: Institute of Electrical and Electronics Engineers Computer Society Abstract: We have realized the first demonstration of imaging in the extreme ultraviolet (EUV) with near-wavelength spatial resolution, 54 nm, using a uniquely compact full-field microscope that can produce images with a single one nanosecond exposure. © 2008 Optical Society of America. (4 refs.) 199. Linearity measurement for ultraviolet ICCD detector Zhao, Yu-Huan (State Key Laboratory of Applied Optics, Changchun Institute of Optics Fine Mechanics and Physics, Chinese Academy of Sciences); Yan, Feng; Lou, Hong-Wei; Sui, Yong-Xin; Yang, Huai-Jiang; Cao, Jian-Lin Source: Guangdian Gongcheng/Opto-Electronic Engineering, v 35, n 8, August, 2008, p 88-91 Language: Chinese ISSN: 1003-501X CODEN: GUGOEC Publisher: Chinese Academy of Sciences Abstract: Based on the theory of radiometry, the measurement technique for linear response of ultraviolet ICCD (UVICCD) detector was studied and a comparative measurement method was presented. The surface of photocathode in the UV-ICCD was set in the same section with the end of fiber belonging to the reference detector. Firstly, the attenuation of irradiance was measured via reference detector. Then, UV-ICCD was set in center of the irradiance field. The outputs of UV-ICCD were recorded according to the corresponding irradiance at that time. At last, relationship curve between output gray value of UV-ICCD and input irradiance was given. Scientific-grade spectrometer with low non-linearity, which was less than 0.2%, was adopted in this project because the accuracy of the measure results depends on the accuracy of the spectrometer. Measurement instrument consists of standard deuterium lamp with high stabilization, optics-attenuator, integrating sphere, reference detector and computer. Auto control is realized via special software during the test. Experimental results show that non-linearity of UV-ICCD is less than 3%, and the uncertainty of comparison measurement method is less than 5%. (7 refs.) 200. Analysis of resolution and feature size in extreme ultraviolet microscopy images Marconi, M.C. (NSF Engineering Research Center for Extreme Ultraviolet Science and Technology, Electrical and Computer Engineering Department, Colorado State University); Wachulak, P.W.; Brewer, C.; Brizuela, F.; Bartels, R.; Menoni, C.S.; Rocca, J.J.; Anderson, E.; Chao, Weilun Source: 2008 Conference on Quantum Electronics and Laser Science Conference on Lasers and Electro-Optics, CLEO/QELS, 2008 Conference on Quantum Electronics and Laser Science Conference on Lasers and Electro-Optics, CLEO/QELS, 2008, p 4552365 最新文献报导 53 XIOPM latest Documents Report ISBN-10: 1557528594 Conference: Conference on Quantum Electronics and Laser Science Conference on Lasers and Electro-Optics, CLEO/QELS 2008, May 4-9 2008, San Jose, CA, United States Publisher: Institute of Electrical and Electronics Engineers Computer Society Abstract: We describe a correlation algorithm that allows for the simultaneous determination of object size and resolution in images of nanoscale objects. The method was used to analyze images recorded with a 13.2 nm laser. ©2008 Optical Society of America. (2 refs.) 201. Analysis of resolution and feature size in extreme ultraviolet microscopy images Marconi, M.C. (NSF Engineering Research Center for Extreme Ultraviolet Science and Technology, Electrical and Computer Engineering Department, Colorado State University); Wachulak, P.W.; Brewer, C.; Brizuela, F.; Bartels, R.; Menoni, C.S.; Rocca, J.J.; Anderson, E.; Chao, Weilun Source: Conference on Quantum Electronics and Laser Science (QELS) - Technical Digest Series, 2008 Conference on and Quantum Electronics and Laser Science Conference Lasers and Electro-Optics, QELS, 2008, p 4552874 Conference: Conference on and Quantum Electronics and Laser Science Conference Lasers and Electro-Optics, QELS 2008, May 4-9 2008, San Jose, CA, United States Publisher: Institute of Electrical and Electronics Engineers Inc. Abstract: We describe a correlation algorithm that allows for the simultaneous determination of object size and resolution in images of nanoscale objects. The method was used to analyze images recorded with a 13.2 nm laser. © 2008 Optical. Society of America. (2 refs.) 202. The Venus ground-based image Active Archive: A database of amateur observations of Venus in ultraviolet and infrared light Barentsen, Geert (Research and Scientific Support Department (RSSD), ESA, ESTEC); Koschny, Detlef Source: Planetary and Space Science, v 56, n 10, August, 2008, p 1444-1449 ISSN: 0032-0633 CODEN: PLSSAE Publisher: Elsevier Ltd Abstract: The Venus ground-based image Active Archive is an online database designed to collect ground-based images of Venus in such a way that they are optimally useful for science. The Archive was built to support ESA's Venus Amateur Observing Project, which utilizes the capabilities of advanced amateur astronomers to collect filtered images of Venus in ultraviolet, visible and near-infrared light. These images complement the observations of the Venus Express spacecraft, which cannot continuously monitor the northern hemisphere of the planet due to its elliptical orbit with apocenter above the south pole. We present the first set of observations available in the Archive and assess the useability of the data set for scientific purposes. © 2008 Elsevier Ltd. All rights reserved. (7 refs.) 203. Design of resolution testing facility for ultraviolet imager Wang, Jiapeng (Changchun Institute of Optics, Fine Mechanics and Physics, Chinese Academy of Sciences); Wang, Shurong; Lin, Guanyu Source: Chinese Optics Letters, v 6, n 7, July, 2008, p 510-512 ISSN: 1671-7694 Publisher: Science Press Abstract: We present a resolution testing system of ultraviolet (UV) imager. In this system, an UV Czerny-Turner monochromator with a small f-number is designed to get more energy as an UV radiation source, and its stray light is rejected effectively by light traps. And UV diffuser is employed in order to get uniform light distribution on the resolving power test target. We also design a novel UV collimator which makes infinite UV testing targets. It can reduce the difficulty of optical design and the machining cost, and utilize UV energy at maximum extent. This facility has been applied in the imaging quality evaluation of the UV instrument, and the results accord with the theoretical analysis. (12 refs.) 204. Fingerprinting analysis of the extracts from Fu Zhi San by high-performance liquid chromatography with ultraviolet and evaporative light scattering detection Zhao, Jingkun (Department of Neurology, Harbin Medical University); Wang, Desheng; Duan, Shurong; Wang, Jianxiu; Bai, Jing; Li, Wenlan Source: 2nd International Conference on Bioinformatics and Biomedical Engineering, iCBBE 2008, 2nd International Conference on Bioinformatics and Biomedical Engineering, iCBBE 2008, 2008, p 1103-1107 Conference: 2nd International Conference on Bioinformatics and Biomedical Engineering, iCBBE 2008, May 16-18 2006, Shanghai, China Sponsor: IEEE Engineering in Medicine and Biology Society (EMB);Univ. Iowa, Cent. 最新文献报导 54 XIOPM latest Documents Report Bioinformatics and Computational Biology;Cent. Devices and Radiological Health, Food and Drug Adm.;Wuhan Univ., Advanced Research Center for Science and Technology;Shanghai Jiaotong Univ., College of Life Science and Technology;et al. Publisher: Institute of Electrical and Electronics Engineers Computer Society Abstract: A high-performance liquid chromatography with ultraviolet and evaporative light scattering detector (HPLCUV-ELSD) method was firstly developed to establish chemical fingerprinting of Fu Zhi San (FZS) and to simultaneously determinate its five major constituents, including baicalin, ferulic acid, ginsenosides Rg1, Re and Rb1 The analysis was performed on a AlltechC18 (5μm, 250 mm x 4.6 mm) with a mixture of acetonitrile and water containing 0.1% acetic acid, and the major constituents were authenticated by comparing their retention times and UV spectra with those of reference compounds. The proposed method was used to analyze twelve extracts from FZS and report data with precision, stability and reproducibility. The results suggest that the described fingerprinting method can simultaneously characterize main chemical constituents from FZS. The proposed method allows obtaining chemical fingerprint and quantitative data of multiple constituents of FZS in one injection and therefore can be widely used as an approach for the comprehensive quality control of TCM. © 2008 IEEE. (14 refs.) 205. An HPLC-ultraviolet detection method for the determination of Z24 in mouse whole blood and its application to pharmacokinetic studies Sheng, Li (Beijing Institute of Pharmacology and Toxicology); Li, Jinglai; Zhang, Zhenqing; Ruan, Jinxiu Source: Journal of Chromatography B: Analytical Technologies in the Biomedical and Life Sciences, v 873, n 1, Sep 15, 2008, p 27-30 ISSN: 1570-0232 CODEN: JCBAAI Publisher: Elsevier Abstract: A sensitive and reproducible high-performance liquid chromatography (HPLC)-UV method for the determination of Z24, a tumorigenesis and angiogenesis inhibitor, has been developed and validated in mouse whole blood. Blood samples were extracted with ether, evaporated, and the residue was reconstituted in mobile phase. An aliquot was separated by isocratic reversed-phase HPLC on a Hypersil ODS-2 column and quantified using UV detection at 390 nm. The mobile phase was 50% (v/v) acetonitrile/water with a flow rate of 0.8 ml/min. A linear curve over the concentration range of 0.05-6 μg/ml (r2 = 0.9976) was obtained. The coefficient of the variation for the intraand inter-day precision ranged from 3.0 to 10.9% and 5.7 to 10.3%, respectively. The absolute recovery of Z24 was 89.2-108.5%. The method is simple, economical and sufficient for in vivo pharmacokinetic studies on Z24. Nonlinear pharmacokinetics was found in mice at doses from 20 to 80 mg/kg. © 2008. (10 refs.) 206. Development and validation of reversed phase liquid chromatographic method utilizing ultraviolet detection for quantification of irinotecan (CPT-11) and its active metabolite, SN-38, in rat plasma and bile samples: Application to pharmacokinetic studies Bansal, Tripta (Department of Pharmaceutics, Faculty of Pharmacy, Jamia Hamdard (Hamdard University)); Awasthi, Anshumali; Jaggi, Manu; Khar, Roop K.; Talegaonkar, Sushama Source: Talanta, v 76, n 5, Sep 15, 2008, p 1015-1021 ISSN: 0039-9140 CODEN: TLNTA2 Publisher: Elsevier Abstract: A new, simple, sensitive and specific reversed-phase high performance liquid chromatographic (HPLC) method using ultraviolet detection was developed and validated for the analysis of CPT-11 (λmax = 254 nm, 365 nm) and its major active metabolite, SN-38 (λmax = 380 nm) in rat plasma and bile. The sample pre-treatment from plasma involved a single protein precipitation step with cold acetonitrile. In case of bile, liquid-liquid extraction with dichloromethane: tert-butyl methyl ether (3:7) was carried out. Topotecan, a structurally related camptothecin, was used as an internal standard. An aliquot of 50 μL was injected onto a C-18 column. The chromatographic separation was achieved by gradient elution consisting of acetonitrile and water (pH 3.0 adjusted with 20% o-phosphoric acid) at a flow rate of 1.0 ml/min. Total run time for each sample was 30 min. All the analytes viz. topotecan, CPT-11, SN-38 were well separated with retention times of 11.4, 13.4 and 15.5 min, respectively. Method was found to be selective, linear (R2 approximately equals 0.999), accurate (recovery ± 15%) and precise ( less than or equal 5% C.V.) in the selected concentration ranges for both the analytes. The quantification limit for CPT-11 was 40 ng ml-1 and for SN-38 was 25 ng ml-1. The percent extraction efficiency was [similar to] 97% for CPT-11 and SN-38 from plasma while extraction recovery of CPT-11 and SN-38 from bile was [similar to] 70% and [similar to] 60%, respectively. The method was successfully used to determine plasma and biliary excretion time profiles of CPT-11 and SN-38, following oral and intravenous CPT-11 administration in rats. In the present study, irinotecan showed an absolute bioavailability of 30% as calculated from the pharmacokinetic data. © 2008 Elsevier B.V. All rights reserved. (22 refs.) 最新文献报导 55 XIOPM latest Documents Report 207. Extreme ultraviolet imaging of electron-heated targets in petawatt laser experiments Ma, Tammy (Department of Mechanical and Aerospace Engineering, University of California at San Diego); MacPhee, Andrew G.; Key, Michael H.; Akli, Kramer U.; Barbee Jr., Troy W.; Mackinnon, Andrew J.; Stephens, Richard B.; Van Woerkom, Linn D.; Zhang, Bingbing; Beg, Farhat N. Source: IEEE Transactions on Plasma Science, v 36, n 4 PART 1, August, 2008, Images in Plasma Science, p 1126-1127 ISSN: 0093-3813 CODEN: ITPSBD Publisher: Institute of Electrical and Electronics Engineers Inc. Abstract: The study of the transport of electrons, and the flow of energy into a solid target or dense plasma, is instrumental in the development of fast-ignition inertial confinement fusion. An extreme ultraviolet (XUV) imaging diagnostic at 256 and 68 eV provides information about heating and energy deposition within petawatt-laser-irradiated targets. The XUV images of several irradiated solid targets are presented. © 2008 IEEE. (4 refs.) 208. 4H-SiC visible-blind single-photon avalanche diode for ultraviolet detection at 280 and 350 nm Hu, Jun (SiCLAB, Department of Electrical and Computer Engineering, Rutgers University); Xin, Xiaobin; Li, Xueqing; Zhao, Jian H.; VanMil, Brenda L.; Lew, Kok-Keong; Myers-Ward, Rachael L.; Eddy Jr., Charles R.; Gaskill, D. Kurt Source: IEEE Transactions on Electron Devices, v 55, n 8, Special Issue on Silicon Carbide Devices and Technology, 2008, p 1977-1983 ISSN: 0018-9383 CODEN: IETDAI Publisher: Institute of Electrical and Electronics Engineers Inc. Abstract: This paper reports on a 4H-SiC single-photon avalanche diode (SPAD) operating at UV wavelengths of 280 and 350 nm. The SPAD shows low dark currents of 20 and 57 fA at 80 V and 90% breakdown voltage, respectively. The quantum efficiency (QE) reaches its peak of 43% at 270 nm and is less than or equal 0.007% at 400 nm, indicating a high UV-to-visible rejection ratio of > 6100. The 4H-SiC SPAD shows a fast self-quenching and a high photon count rate of 1.44 MHz in the passive-quenching mode. At the wavelength of 280 nm, a single-photon detection efficiency (SPDE) of 2.83% with a low dark count rate of 22 kHz is achieved at the reverse bias of 116.8 V. The SPDE at 350 nm is lower, which is 0.195%, owing to the correspondingly smaller QE. Optimization measurements were conducted on SPDE as a function of voltage bias and signal output threshold. © 2008 IEEE. (18 refs.) 209. Monolithically integrated AlGaN/GaN/AlN-based solar-blind ultraviolet and near-infrared detectors Hofstetter, D. (Institute of Physics, University of Neuchatel); Theron, R.; Baumann, E.; Giorgetta, F.R.; Golka, S.; Strasser, G.; Guillot, F.; Monroy, E. Source: Electronics Letters, v 44, n 16, , 2008, ISSN: 0013-5194 CODEN: ELLEAK Publisher: Institution of Engineering and Technology Abstract: Closely spaced, monolithically integrated photodetectors in two largely different wavelengths ranges are demonstrated. The device structure was grown by plasma-assisted molecular-beam epitaxy on an AlN-on-sapphire template, and it consists of a Si-doped AlGaN thin film, and a nearly strain compensated 40 period AlN/GaN superlattice with 1.0 nm-thick GaN quantum wells and 2.0 nm-thick AlN barriers. The entire structure is covered with an AlGaN cap. The superlattice constitutes the active region for the infrared detector, while the AlGaN buffer layer serves as active area for the ultraviolet detector. The photoconductive ultraviolet detector has a long wavelength cutoff at 250 nm, whereas the photovoltaic near-infrared detector has a centre wavelength of 1.37 μm. © 2008 The Institution of Engineering and Technology. (6 refs.) Optical tweezers/ Photochromic 210 Author(s): Su, JH (Su, Junhua); Chen, J (Chen, Jian); Zeng, F (Zeng, Fang); Chen, QM (Chen, Qiming); Wu, SZ (Wu, Shuizhu); Tong, Z (Tong, Zhen) Title: Synthesis and photochromic property of nanoparticles with spiropyran moieties via one-step miniemulsion polymerization Source: POLYMER BULLETIN, 61 (4): 425-434 OCT 2008 Abstract: Photochromic nanoparticles with spiropyran moieties were prepared by a facile one-step miniemulsion polymerization. The nanoparticle dispersion was obtained by mixing the monomers, spiropyran-containing molecules and hydrophobe, dispersing them into an aqueous solution with surfactant, subjecting the dispersion to ultrasonification and polymerizing 最新文献报导 56 XIOPM latest Documents Report the monomers by using a water soluble initiator. The shape and size of the nanoparticles was determined with the atomic force microscope (AFM) and dynamic light scattering (DLS), and the determined average diameter of the nanoparticles ranges from 30 nm to 60 nm. The absorption and fluorescence spectra for the nanoparticles dispersions reveal that the spiropyran molecules were successfully incorporated in the polymer nanoparticles. Moreover, the nanoparticle dispersions were found to exhibit enhanced photo-reversibility, photo-stability and relatively fast photoresponsive property compare to the same species in aqueous solution. -------------------------------------------------------------------------------211 Author(s): Benito, DC (Benito, D. C.); Carberry, DM (Carberry, D. M.); Simpson, SH (Simpson, S. H.); Gibson, GM (Gibson, G. M.); Padgett, MJ (Padgett, M. J.); Rarity, JG (Rarity, J. G.); Miles, MJ (Miles, M. J.); Hanna, S (Hanna, S.) Title: Constructing 3D crystal templates for photonic band gap materials using holographic optical tweezers Source: OPTICS EXPRESS, 16 (17): 13005-13015 AUG 18 2008 Abstract: A simple and robust method is presented for the construction of 3-dimensional crystals from silica and polystyrene microspheres. The crystals are suitable for use as templates in the production of three-dimensional photonic band gap (PBG) materials. Manipulation of the microspheres was achieved using a dynamic holographic assembler (DHA) consisting of computer controlled holographic optical tweezers. Attachment of the microspheres was achieved by adjusting their colloidal interactions during assembly. The method is demonstrated by constructing a variety of 3dimensional crystals using spheres ranging in size from 3 mu m down to 800 nm. A major advantage of the technique is that it may be used to build structures that cannot be made using self-assembly. This is illustrated through the construction of crystals in which line defects have been deliberately included, and by building simple cubic structures. (C) 2008 Optical Society of America. -------------------------------------------------------------------------------212 Author(s): Gibson, GM (Gibson, Graham M.); Leach, J (Leach, Jonathan); Keen, S (Keen, Stephen); Wright, AJ (Wright, Amanda J.); Padgett, MJ (Padgett, Miles J.) Title: Measuring the accuracy of particle position and force in optical tweezers using high-speed video microscopy Source: OPTICS EXPRESS, 16 (19): 14561-14570 SEP 15 2008 Abstract: We assess the performance of a CMOS camera for the measurement of particle position within optical tweezers and the associated autocorrelation function and power spectrum. Measurement of the displacement of the particle from the trap center can also be related to the applied force. By considering the Allan variance of these measurements, we show that such cameras are capable of reaching the thermal limits of nanometer and femtonewton accuracies, and hence are suitable for many of the applications that traditionally use quadrant photodiodes. As an example of a multi-particle measurement we show the hydrodynamic coupling between two particles. (C) 2008 Optical Society of America. -------------------------------------------------------------------------------213 Author(s): Stilgoe, AB (Stilgoe, Alexander B.); Nieminen, TA (Nieminen, Timo A.); Knoner, G (Knoener, Gregor); Heckenberg, NR (Heckenberg, Norman R.); Rubinsztein-Dunlop, H (Rubinsztein-Dunlop, Halina) Title: The effect of Mie resonances on trapping in optical tweezers Source: OPTICS EXPRESS, 16 (19): 15039-15051 SEP 15 2008 Abstract: We calculate trapping forces, trap stiffness and interference effects for spherical particles in optical tweezers using electromagnetic theory. We show the dependence of these on relative refractive index and particle size. We investigate resonance effects, especially in high refractive index particles where interference effects are expected to be strongest. We also show how these simulations can be used to assist in the optimal design of traps. (C) 2008 Optical Society of America. -------------------------------------------------------------------------------214 Author(s): Tanaka, Y (Tanaka, Yoshio); Kawada, H (Kawada, Hiroyuki); Hirano, K (Hirano, Ken); Ishikawa, M (Ishikawa, Mitsuru); Kitajima, H (Kitajima, Hiroyuki) Title: Automated manipulation of non-spherical micro-objects using optical tweezers combined with image processing techniques Source: OPTICS EXPRESS, 16 (19): 15115-15122 SEP 15 2008 Abstract: Automated optical trapping of non-spherical objects offers great flexibility as a non-contact micromanipulation tool in various research fields. Computer vision control enables fruitful applications of automated manipulation in biology and 最新文献报导 57 XIOPM latest Documents Report material science. Here we demonstrate fully-automated, simultaneous, independent trapping and manipulation of multiple non-spherical objects using multiple-force optical clamps. Customized real-time feature recognition and trapping beam control algorithms are also presented. (C) 2008 Optical Society of America. -------------------------------------------------------------------------------215 Author(s): Brust, T (Brust, Thomas); Draxler, S (Draxler, Simone); Malkmus, S (Malkmus, Stephan); Schulz, C (Schulz, Christine); Zastrow, M (Zastrow, Marc); Ruck-Braun, K (Rueck-Braun, Karola); Zinth, W (Zinth, Wolfgang); Braun, M (Braun, Markus) Title: Ultrafast dynamics and temperature effects on the quantum efficiency of the ring-opening reaction of a photochromic indolylfulgide Source: JOURNAL OF MOLECULAR LIQUIDS, 141 (3): 137-139 JUN 30 2008 Abstract: The ultrafast ring-opening reaction of the molecular switch 1,2-Dimethyl-3-indolylfulgide dissolved in acetonitrile is investigated by temperature dependent quantum efficiency measurements and time-resolved transient absorption spectroscopy in the ultraviolet and visible spectral range. The photoreaction is found to be thermally activated with an activation energy of about 1640 cm(-1). The transient absorption signal is bi-exponential with the time constants tau(1) = 0.7 ps and tau(2) = 12 ps. The fast time constant is due to solvation dynamics, while the main component tau(2) is attributed to the excited state lifetime and product formation. A long-lived intermediate state in the photoreaction can be excluded. (c) 2008 Elsevier B.V. All rights reserved. -------------------------------------------------------------------------------216 Author(s): Bugaenko, TY (Bugaenko, T. Yu.); Radzhabov, EA (Radzhabov, E. A.); Ivashechkin, VF (Ivashechkin, V. F.) Title: Thermal decay of photochromic color centers in CaF2, SrF2, and BaF2 crystals doped by La and Y impurities Source: PHYSICS OF THE SOLID STATE, 50 (9): 1671-1673 SEP 2008 Abstract: The absorption spectra of photochromic centers in CaF2, SrF2, and BaF2 crystals doped by La and Y impurities and thermal decay of the centers in the temperature range 80-600 K are investigated. Under low-temperature x-ray irradiation, ionized photochromic color (PC+) centers are generated in La- and Y-doped CaF2 crystals and in a Ladoped SrF2 crystal. It is revealed that, upon heating of the CaF2-LaF3 crystal, PC+ centers are transformed into photochromic color (PC) centers. In the SrF2-YF3 crystal irradiated at room temperature, photochromic color centers are generated as well. All color centers decay at a temperature of approximately 600 K. After irradiation of the BaF2YF3 crystal at a temperature of 80 K, absorption bands are observed at energies of 2.25 and 3.60 eV, which are related to neither PC centers nor PC+ centers. -------------------------------------------------------------------------------217 Author(s): Islamova, NI (Islamova, Nadezhda I.); Chen, X (Chen, Xi); DiGirolamo, JA (DiGirolamo, Jessica A.); Silva, Y (Silva, Yenia); Lees, WJ (Lees, Watson J.) Title: Thermal stability and photochromic properties of a fluorinated indolylfulgimide in a protic and aprotic solvent Source: JOURNAL OF PHOTOCHEMISTRY AND PHOTOBIOLOGY A-CHEMISTRY, 199 (1): 85-91 SEP 5 2008 Abstract: The photochromic properties and thermal stability of a newly synthesized fluorinated N-ethoxycarbonylmethyl indolylfulgimide substituted on the imide nitrogen were examined in a protic and aprotic environment. The absorption spectra and extinction coefficients of the Z- and C-forms of the fluorinated indolylfulgimide (open and closed, respectively) were measured in a binary 70/30 ethanol/water system and in toluene. The results demonstrated a favorable bathochromic shift of the absorption maxima for both the open and closed forms of the fulgimide when the solvent was changed from aprotic toluene to protic aqueous ethanol. In addition, the photochemical stability of the new fulgimide was found to be high (0.056 and 0.020% degradation each time the fulgimide is cycled between the open and closed form in 70/30 ethanol/water and in toluene, respectively). The thermal stability of both forms of the fulgimide in 70/30 ethanol/water at 50 C, toluene at 80 C, and polymer film (PMMA) at 80 degrees C was measured using UV-vis and/or H-1 NMR spectroscopy. Both forms of indolylfulgimide display high hydrolytic stability in 70/30 ethanol/water at 50 C, with the Z- and C-forms degrading 1.3 and 1.2%/day respectively, based on H NMR data. At 80 C in toluene the less stable Z-form lost about 20%/day. (C) 2008 Published by Elsevier B.V. -------------------------------------------------------------------------------218 最新文献报导 58 XIOPM latest Documents Report Author(s): Pirozerskii, AL (Pirozerskii, A. L.); Charnaya, EV (Charnaya, E. V.); Vasil'ev, MI (Vasil'ev, M. I.); Lebedeva, EL (Lebedeva, E. L.) Title: Temperature features of ultrasonic attenuation in photochromic glasses with copper chloride nanocrystals Source: ACOUSTICAL PHYSICS, 54 (5): 647-653 SEP 2008 Abstract: The results of acoustooptic measurements of the attenuation coefficient of longitudinal ultrasonic waves in copper halide photochromic glasses are presented for wide temperature (140-550 K) and frequency (190-790 MHz) ranges. In the low-temperature region (T < 230 K), a wide relaxational peak is observed at a frequency of 629 MHz. Presumably, this peak is related to the motion of copper ions in the glass lattice. In the high-temperature region (up to 550 K), the attenuation coefficient does not depend on temperature. The presence of the temperature plateau is explained in the framework of the two-level system model with weak asymmetry. -------------------------------------------------------------------------------219 Author(s): Kumar, S (Kumar, Satish); Hernandez, D (Hernandez, David); Hoa, B (Hoa, Brenda); Lee, Y (Lee, Yuna); Yang, JS (Yang, Julie S.); McCurdy, A (McCurdy, Alison) Title: Synthesis, photochromic properties, and light-controlled metal complexation of a naphthopyran derivative Source: ORGANIC LETTERS, 10 (17): 3761-3764 SEP 4 2008 Abstract: A light-controlled reversible binding switch based on photochromic 3H-naphtho[2,1-b]pyran is under development for studying cellular oscillatory calcium signals. The binding affinities of the closed and open forms of substituted naphthopyran 1 for Ca2+, Mg2+, and Sr2+ in buffer were determined. The photochemically ring-opened form of the receptor exhibited increased affinity compared to the thermally stable closed form of the receptor. The binding affinity difference for Ca2+ was similar to 77-fold at pH 7.6. -------------------------------------------------------------------------------220 Author(s): Berthet, J (Berthet, Jerome); Micheau, JC (Micheau, Jean-Claude); Lokshin, V (Lokshin, Vladimir); Vales, M (Vales, Magali); Vermeersch, G (Vermeersch, Gaston); Delbaere, S (Delbaere, Stephanie) Title: Wavelength-dependent reactivity of a quinolinone: Toward a photochromic three-state system Source: ORGANIC LETTERS, 10 (17): 3773-3776 SEP 4 2008 Abstract: The photochemical reactivity of the quinolinone 3 was investigated using NMR by monitoring its reactions under appropriate irradiation wavelengths. Besides the irreversible formation of degradation products which were structurally identified, the reversible formation of the enol 4 and cyclobutenol 5 was also observed. The enol and cyclobutenol can be switched or reversed back to the quinolinone 3, resulting in a photochromic three-state system in which the relative ratio of the three components largely depends on the irradiation wavelength used. -------------------------------------------------------------------------------221 Author(s): Maranski, K (Maranski, Krzysztof); Kucharski, S (Kucharski, Stanislaw); Ortyl, E (Ortyl, Ewelina); Nunzi, JM (Nunzi, Jean-Michel); Ahmadi-Kandjani, S (Ahmadi-Kandjani, Sohrab); Dabos-Seignon, S (DabosSeignon, Sylvie); Chan, SW (Chan, Sui-Wai); Barille, R (Barille, Regis) Title: Second harmonic generation and photochromic grating in polyurethane films containing diazo isoxazole chromophore Source: OPTICAL MATERIALS, 30 (12): 1832-1839 AUG 2008 Abstract: The chromophoric intermediate: 2,2'-({4-[(E)-(5-methylisoxazol-3-yl)diazenyl]phenly}-imino)diethanol was used in polyaddition reaction with di-isocyanate to obtain a new polyurethane polymeric material showing nonlinear optical and photochromic properties. The maximum absorption band of the polymer film was at 418 rim. The illumination of the film with crossed beams of the 488 nm Ar+ laser yielded surface relief grating of regular structure. Measurement of the frequency doubling signal with 1064 nm laser indicated the polymer as interesting material for photooptical applications. The measured nonlinear optical coefficient, d(33), reached 90.2 pm/V. (c) 2007 Elsevier B.V. All rights reserved. -------------------------------------------------------------------------------222 Author(s): Fukuda, K (Fukuda, Katsutoshi); Akatsuka, K (Akatsuka, Kosho); Ebina, Y (Ebina, Yasuo); Ma, R (Ma, Renzhi); Takada, K (Takada, Kazunori); Nakai, I (Nakai, Izumi); Sasaki, T (Sasaki, Takayoshi) Title: Exfoliated nanosheet crystallite of cesium tungstate with 2D pyrochlore structure: Synthesis, characterization, and photochromic properties Source: ACS NANO, 2 (8): 1689-1695 AUG 2008 Abstract: 最新文献报导 59 XIOPM latest Documents Report Layered cesium tungstate, Cs6+xW11O36, with two-dimensional(2D) pyrochlore structure was exfoliated into colloidal unilamellar sheets through a soft-chemical process. Interlayer Cs ions were replaced with protons by acid exchange, and quaternary ammonium ions were subsequently intercalated under optimized conditions. X-ray diffraction (XRD) measurements on gluelike sediment recovered from the colloidal suspension by centrifugation showed a broad pattern of a pronounced wavy profile, which closely matched the square of calculated structure factor for the single host layer. This indicates the total delamination of the layered tungstate into nanosheets of Cs4W11O362-. Microscopic observations by transmission electron microscopy and atomic force microscopy clearly revealed the formation of unilamellar crystallites with a very high 2D anisotropy, a thickness of only similar to 2 nm versus lateral size up to several micrometers. In-plane XRD analysis confirmed that the 2D pyrochlore structure was retained. The colloidal cesium tungstate nanosheet showed strong absorption of UV light with sharp onset, suggesting a semiconducting nature. Analysis of the absorption profile provided 3.6 eV as indirect band gap energy, which is 0.8 eV larger than that of the bulk layered precursor, probably due to size quantization. The nanosheet exhibited highly efficient photochromic properties, showing reversible color change upon UV irradiation. Fiber Amplifier 223 Author(s): Jha, A (Jha, Animesh); Joshi, P (Joshi, Purushottam); Shen, SX (Shen, Shaoxiong) Title: Effect of nano-scale crystal field on the broadening of Er3+-emission in sodium tellurite glass ceramics Source: OPTICS EXPRESS, 16 (18): 13526-13533 SEP 1 2008 Abstract: In this paper we report the effect of heat treatment of 10 mol% Na2O- 89.5 mol% TeO2 glass for studying the fluorescence and line broadening behavior of Er- ions in the glass- ceramic matrix. Controlled crystal growth measurements using the X-ray line broadening technique for samples heat treated in the temperature range of 583-693 K were carried out and compared with the photoluminescence studies. The influence of crystal growth on line broadening of I-4(13/2) spectra and metastable lifetime of I-4(13/2) level is compared for various heat treatment temperatures. The full- widthofhalf maxima increase with increasing heat treatment temperature and then fall rapidly at high temperatures. (c) 2008 Optical Society of America. -------------------------------------------------------------------------------224 Author(s): Turchinovich, D (Turchinovich, Dmitry); Liu, XM (Liu, Xiaomin); Laegsgaard, J (Laegsgaard, Jesper) Title: Monolithic all-PM femtosecond Yb-fiber laser stabilized with a narrow-band fiber Bragg grating and pulse-compressed in a hollow-core photonic crystal fiber Source: OPTICS EXPRESS, 16 (18): 14004-14014 SEP 1 2008 Abstract: We report on an environmentally stable self-starting monolithic (i.e. without any free-space coupling) all-polarizationmaintaining (PM) femtosecond Yb-fiber laser, stabilized against Q-switching by a narrow-band fiber Bragg grating and modelocked using a semiconductor saturable absorber mirror. The laser output is compressed in a spliced-on hollowcore PM photonic crystal fiber, thus providing direct end-of-the-fiber delivery of pulses of around 370 fs duration and 4 nJ energy with high mode quality. Tuning the pump power of the end amplifier of the laser allows for the control of output pulse bandwidth and duration. Our experimental results are in good agreement with the theoretical predictions. -------------------------------------------------------------------------------225 Author(s): Dajani, I (Dajani, Iyad); Zeringue, C (Zeringue, Clint); Bronder, TJ (Bronder, T. Justin); Shay, T (Shay, Thomas); Gavrielides, A (Gavrielides, Athanasios); Robin, C (Robin, Craig) Title: A theoretical treatment of two approaches to SBS mitigation with two-tone amplification Source: OPTICS EXPRESS, 16 (18): 14233-14247 SEP 1 2008 Abstract: A technique that employs two seed signals for the purpose of mitigating stimulated Brillouin scattering (SBS) effects in narrow-linewidth Yb-doped fiber amplifiers is investigated theoretically by constructing a self-consistent model that incorporates the laser gain, SBS, and four-wave mixing (FWM). The model reduces to solving a two-point boundary problem consisting of an 8x8 system of coupled nonlinear differential equations. Optimal operating conditions are determined by examining the interplay between the wavelength separation and power ratio of the two seeds. Two variants of this 'two-tone' amplification are considered. In one case the wavelength separation is precisely twice the Brillouin shift, while the other case considers a greater wavelength separation. For the former case, a two-fold increase in total output power over a broad range of seed power ratios centered about a ratio of approximately 2 is obtained, but 最新文献报导 60 XIOPM latest Documents Report with fairly large FWM. For the latter case, this model predicts an approximately 100% increase in output power (at SBS threshold with no signs of FWM) for a 'two-tone' amplifier with seed signals at 1064nm and 1068nm, compared to a conventional fiber amplifier with a single 1068nm seed. More significantly for this case, it is found that at a wavelength separation greater than 10nm, it is possible to appreciably enhance the power output of one of the laser frequencies. (c) 2008 Optical Society of America. -------------------------------------------------------------------------------226 Author(s): Dawson, JW (Dawson, Jay W.); Messerly, MJ (Messerly, Michael J.); Beach, RJ (Beach, Raymond J.); Shverdin, MY (Shverdin, Miroslav Y.); Stappaerts, EA (Stappaerts, Eddy A.); Sridharan, AK (Sridharan, Arun K.); Pax, PH (Pax, Paul H.); Heebner, JE (Heebner, John E.); Siders, CW (Siders, Craig W.); Barty, CPJ (Barty, C. P. J.) Title: Analysis of the scalability of diffraction-limited fiber lasers and amplifiers to high average power Source: OPTICS EXPRESS, 16 (17): 13240-13266 AUG 18 2008 Abstract: We analyze the scalability of diffraction-limited fiber lasers considering thermal, non-linear, damage and pump coupling limits as well as fiber mode field diameter ( MFD) restrictions. We derive new general relationships based upon practical considerations. Our analysis shows that if the fiber's MFD could be increased arbitrarily, 36 kW of power could be obtained with diffraction-limited quality from a fiber laser or amplifier. This power limit is determined by thermal and non-linear limits that combine to prevent further power scaling, irrespective of increases in mode size. However, limits to the scaling of the MFD may restrict fiber lasers to lower output powers. (C) 2008 Optical Society of America. -------------------------------------------------------------------------------227 Author(s): Kim, JH (Kim, Jae Hun); Chen, MK (Chen, Meng-Ku); Yang, CE (Yang, Chia-En); Lee, J (Lee, Jon); Shi, KB (Shi, Kebin); Liu, ZW (Liu, Zhiwen); Yin, S ((Shizhuo) Yin, Stuart); Reichard, K (Reichard, Karl); Ruffin, P (Ruffin, Paul); Edwards, E (Edwards, Eugene); Brantley, C (Brantley, Christina); Luo, C (Luo, Claire) Title: Broadband supercontinuum generation covering UV to mid-IR region by using three pumping sources in single crystal sapphire fiber Source: OPTICS EXPRESS, 16 (19): 14792-14800 SEP 15 2008 Abstract: In this paper, we demonstrate that the the bandwidth of the supercontinuum spectrum generated in a large mode area sapphire fiber can be enhanced by employing triple pumping sources. Three pumping sources with wavelengths of 784nm, 1290nm, and 2000nm are launched into a single crystal sapphire fiber that is 5cm in length and has a core diameter of 115 mu m. The nonlinear interactions due to self-phase modulation and four-wave mixing form a broadband supercontinuum that covers the UV, visible, near-IR and lower mid-IR regions. Furthermore, we explore the possibility of generating a broadband supercontinuum expanding from the UV to far-IR region by increasing the number of pumping sources with wavelengths in the mid- and far-IR. (C) 2008 Optical Society of America. -------------------------------------------------------------------------------228 Author(s): Watekar, PR (Watekar, Pramod R.); Lin, AX (Lin, Aoxiang); Han, WT (Han, Won-Taek); Ju, SM (Ju, Seongmin) Title: Effect of helical bending on gain beyond 1650-nm of an Er-doped optical fiber amplifier Source: JOURNAL OF THE KOREAN PHYSICAL SOCIETY, 53 (3): 1327-1330 Part 1 Sp. Iss. SI SEP 2008 Abstract: An Er-doped optical fiber amplifier sensitized with Yb ions was developed with a two-cores three-claddings layer structure. Extended L-band amplification over 1650-nm was achieved upon 980-nm pumping with helical bending. The gain after helical bending was about 12 dB at 1700-nm. -------------------------------------------------------------------------------229 Author(s): Chung, YD (Chung, Yong-Duck); Choi, KS (Choi, Kwang-Seong); Sim, JS (Sim, Jae-Sik); Kwon, YH (Kwon, Yong-Hwan); Kim, J (Kim, Jeha) Title: Temperature-dependent characteristics of electroabsorption modulator modules for analog 60-GHz applications Source: JOURNAL OF THE KOREAN PHYSICAL SOCIETY, 53 (3): 1538-1541 Part 1 Sp. Iss. SI SEP 2008 Abstract: We developed an electroabsorption modulator module for analog 60-GHz radio-over-fiber (RoF) applications. The ternperature-dependent characteristics of an electroabsorption modulator were demonstrated and analyzed from 15 degrees C to 45 degrees C. The insertion loss increased from 13-1. dB to 17.2 dB and the extinction ratio from 0 V to -5 V also increased from 14.5 dB to 26.2 dB with temperature at 0-dBm input power. The optimum operation voltages 最新文献报导 61 XIOPM latest Documents Report with the highest modulation efficiencies at different temperatures were investigated using a 60-GHz RoF link. The gain of the RoF link decreased by as much as 7 dB from 25 degrees C to 45 degrees C at a bias voltage -1.5 V; the gain of the RoF link had a maximum value at, 25 degrees C. For the RoF link, a steady gain could be obtained by adjusting the bias voltage to an optimum value for the given temperature. -------------------------------------------------------------------------------230 Author(s): Girard, SL (Girard, Simon Lambert); Chen, HX (Chen, Hongxin); Schinn, GW (Schinn, Gregory W.); Piche, M (Piche, Michel) Title: Frequency-modulated, tunable, semiconductor-optical-amplifier-based fiber ring laser for linewidth and line shape control Source: OPTICS LETTERS, 33 (16): 1920-1922 AUG 15 2008 Abstract: We report how the linewidth and line shape of a tunable semiconductor-optical-amplifier-based fiber ring laser can be actively adjusted by applying an intracavity frequency modulation to the laser. Frequency-modulated laser operation is achieved by driving the phase modulator frequency close to the cavity axial-mode spacing, leading to a constantamplitude laser output having a periodically varying instantaneous frequency. The resulting linewidth varies proportionally with the inverse of the frequency detuning, and it is adjustable from submegahertz to over more than 5 GHz. By appropriate selection of the modulating waveform we have synthesized a near-Gaussian output line shape; other line shapes can be produced by modifying the modulating waveform. Experimental observations are in good agreement with a simple model. (c) 2008 Optical Society of America. -------------------------------------------------------------------------------231 Author(s): Liaw, SK (Liaw, S. -K.); Hong, KL (Hong, K. -L.); Jhong, GS (Jhong, G. -S.); Ivanova, TY (Ivanova, T. Yu.); Manshina, AA (Manshina, A. A.); Tveryanovich, YS (Tveryanovich, Yu. S.) Title: Pump slope-improved fiber-ring laser by recycling the residual pumping power Source: LASER PHYSICS, 18 (9): 1040-1043 SEP 2008 Abstract: We investigate an improvement in the pump slope efficiency for an erbium-doped fiber-ring laser. The method is based on the residual pump power reused by means of a fiber mirror. Under the conditions of a 4-m erbium-doped fiber (EDF), 10 mW of pump power, and a 99% reflectivity of a fiber-Bragg grating, the pump slope efficiency may reach 19.70% compared to 15.37% for a conventional fiber-ring laser. The maximum lasing power is increased from 14.6 to 18.7 mW corresponding to a 1.07-dB lasing power enhancement. The side-mode suppression ratio is as high as 67.6 dB with a line width of less than 0.05 nm. -------------------------------------------------------------------------------232 Author(s): Liaw, SK (Liaw, S. -K.); Hong, KL (Hong, K. -L.) Title: Inclination sensing based on a fiber-ring laser and a fiber-Bragg grating with a precise resolution Source: LASER PHYSICS, 18 (9): 1044-1047 SEP 2008 Abstract: We design an inclination-sensing system based on a fiber-ring laser integrated fiber-Bragg grating (FBG) whose peak wavelength is changed by the axial strain. By replacing a conventional broadband light source with the fiber-ring laser, we raise the sensing power to 3.1 dBm, the peak-to-noise ratio to 65.31 dB, and reduce the 3-dB bandwidth to 0.06 nm. Thus, the sensitivity and resolution of the proposed system are greatly improved. By using an FBG integrated with a pendulum ball used as a sensor head, the resolution of the angular inclination could reach 0.015 nm per degree. These specifications are qualified for the general practice of the pendulum-sensing system. -------------------------------------------------------------------------------233 Author(s): Shao, JF (Shao, J. F.); Shen, QS (Shen, Q. S.); Wu, ZJ (Wu, Z. J.); Zhan, L (Zhan, L.); Li, SL (Li, S. L.); Cao, ZQ (Cao, Z. Q.) Title: Fiber-ring laser with tunable optical bistability Source: LASER PHYSICS, 18 (9): 1048-1051 SEP 2008 Abstract: The structure of combining two segments of erbium-doped fiber (EDF) together-one EDF acting as an amplifier and the other as an absorber-has a special gain characteristic curve which has a maximum gain with an increase in the input signal power. This special gain characteristic curve can lead to an optical bistability (OB) phenomenon in a fiber-ring laser employing an EDF of this structure. By adjusting the pump light power injected into the second segment of the EDF, we can change the behavior of the absorber and can, therefore, control the range of the bistability region. A method is proposed to calculate the tunable optical bistability, and the calculation result is in accordance with our experiment. 最新文献报导 62 XIOPM latest Documents Report -------------------------------------------------------------------------------234 Author(s): Oltean, M (Oltean, Mihai); Muntean, O (Muntean, Oana) Title: Exact cover with light Source: NEW GENERATION COMPUTING, 26 (4): 329-346 AUG 2008 Abstract: We suggest a new optical solution for solving the YES/NO version of the Exact Cover problem by using the massive parallelism of light. The idea is to build an optical device which can generate all possible solutions of the problem and then to pick the correct one. In our case the device has a graph-like representation and the light is traversing it by following the routes given by the connections between nodes. The nodes are connected by arcs in a special way which lets us to generate all possible covers (exact or not) of the given set. For selecting the correct solution we assign to each item, from the set to be covered, a special integer number. These numbers will actually represent delays induced to light when it passes through arcs. The solution is represented as a subray arriving at a certain moment in the destination node. This will tell us if an exact cover does exist or not. -------------------------------------------------------------------------------235 Author(s): Yang, W (Yang, Wei); Zhang, M (Zhang, Min); Han, HN (Han, Huining); Cai, LB (Cai, Libo); Ye, PD (Ye, Peida) Title: Analysis of photonic frequency upconversion for radio-on-fiber applications using two-pump four-wave mixing in semiconductor optical amplifiers - art. no. 075004 Source: OPTICAL ENGINEERING, 47 (7): 75004-75004 JUL 2008 Abstract: A novel scheme of photonic frequency conversion based on two-pump four-wave mixing in a semiconductor optical amplifier is proposed. Characterized by its wide conversion range, the proposed scheme has the potential to generate millimeter waves at much higher frequency and convert several signal channels simultaneously. The system performance is analyzed through a numerical model, and the effect of the pump-signal pulse parameters on the conversion efficiency is discussed. (c) 2008 Society of Photo-Optical Instrumentation Engineers. -------------------------------------------------------------------------------236 Author(s): Cheng, J (Cheng, Jay) Title: Constructions of optical 2-to-1 FIFO multiplexers with a limited number of recirculations Source: IEEE TRANSACTIONS ON INFORMATION THEORY, 54 (9): 4040-4052 SEP 2008 Abstract: Recently, there has been a lot of attention in the literature on a less well-known aspect of queueing theory, the theory of the constructions of queues. Such an interest originates mainly from optical packet switching due to the lack of optical buffers. These constructions of optical queues are based on optical switches and fiber delay lines (SDL). Theoretical studies in the SDL constructions have been recently reported for the constructions of various types of optical queues, including output-buffered switches, first-in-first-out (FIFO) multiplexers, FIFO queues, last-in-first-out (LIFO) queues, priority queues, linear compressors, nonovertaking delay lines, and flexible delay lines. In this paper, we consider the constructions of optical 2-to-1 FIFO multiplexers with a limited number of recirculations through the fibers, which is a very important practical feasibility issue on the constructions of optical queues that has not been theoretically addressed before. Specifically, we consider the constructions of optical 2-to-1 FIFO multiplexers with buffer size at least 2(n)-1 by using a feedback system consisting of an (M + 2) x (M + 2) optical crossbar switch and M fiber delay lines under a simple packet routing policy and under the limitation that each packet can be recirculated through the M fibers at most k times. In one of our previous works, we have shown that this can be done by using n fibers with delays 1, 2, 2(2) ,..., 2(n-1) if there is no limitation on the number of recirculations through the fibers. The main idea in our constructions in this paper is to use extra fibers (other than the n fibers with delays 1, 2, 2(2) ,..., 2(n-1) with appropriately chosen delays to emulate the effective delays of the concatenations of some of the n fibers with delays 1, 2, 2(2) ,..., 2(n-1) so that the number of recirculations is reduced by so doing. It turns out that the number of fibers needed and their delays are determined based on a dynamic programming formulation obtained through a divide-and-conquer approach. We obtain a closed-form expression for the number of fibers needed in our constructions, and show that there are ((k)(r)) possible choices for the delays of the required fibers, where r is the remainder of n divided by k. Furthermore, we give the optimal choice of the fiber delays that achieves the maximum buffer size among the ((k)(r)) possible choices. Finally, we show that when n = k or n >= 2k, such an optimal choice also requires the minimum total fiber length among the ((k)(r)) possible choices. -------------------------------------------------------------------------------237 Author(s): Liu, YH (Liu, Y. H.); Chen, YJ (Chen, Y. J.); Lin, YF (Lin, Y. F.); Luo, ZD (Luo, Z. D.); Huang, YD (Huang, Y. D.) 最新文献报导 63 XIOPM latest Documents Report Title: Effect of Bi2O3 on spectroscopic properties and energy transfer in Yb3+-Er3+-Co-doped bismuth borate glasses for 1.5 mu m optical amplifiers Source: OPTICAL MATERIALS, 30 (12): 1883-1888 AUG 2008 Abstract: In this paper, the effect of Bi2O3 on the optical absorption and emission, energy transfer, and gain property of Yb3+Er3+-co-doped bismuth borate glasses has been investigated. An increase of the emission cross-section and fluorescence lifetime of Er3+ ions around 1.5 mu m with Bi2O3 content was shown. The increase of Bi2O3 content is also beneficial to obtaining a large absorption cross-section at 980 nm and increasing the energy transfer from Yb3+ to Er3+. Furthermore, in the 45Bi(2)O(3)-55B(2)O(3) glass, gain curve is almost flat in the range from 1.53 to 1.60 mu m. The results indicate that the Yb3+-Er3+-co-doped bismuth borate glasses have good prospect as a candidate of gain medium for 1.5 mu m broadband amplifier. (c) 2007 Elsevier B.V. All rights reserved. -------------------------------------------------------------------------------238 Author(s): Nemova, G (Nemova, Galina); Kashyap, R (Kashyap, Raman) Title: High-power long-period-grating-assisted erbium-doped fiber amplifier Source: JOURNAL OF THE OPTICAL SOCIETY OF AMERICA B-OPTICAL PHYSICS, 25 (8): 1322-1327 AUG 2008 Abstract: We present a new theoretical scheme for a high-power Er:`-doped fiber amplifier assisted with a long period grating (LPG). This cladding-pumped amplifier is predicted to generate up to -2.25 kW of continuous-wave output power at 1531 nm with a power conversion efficiency of similar to 0.83. This device consists of an Er3+-doped cladding and an undoped core pumped with a high-power laser at a wavelength of 1480 nm. The LPG imprinted in the fiber core transfers a weak input signal propagating in the core mode of a single-mode fiber into a predetermined cladding mode, dramatically increasing the effective mode-area of the signal and the threshold powers for unwanted nonlinear effects such as stimulated Raman and Brillouin scattering. Depending on the choice of the cladding mode used for amplification, a second LPG imprinted at the end of the Er3+-doped fiber may be used to transfer the amplified signal into a large core output fiber with high efficiency, providing a high-quality output beam in a fundamental mode. (C) 2008 Optical Society of America. -------------------------------------------------------------------------------239 Author(s): Hughes, M (Hughes, M.); Suzuki, T (Suzuki, T.); Ohishi, Y (Ohishi, Y.) Title: Advanced bismuth-doped lead-germanate glass for broadband optical gain devices Source: JOURNAL OF THE OPTICAL SOCIETY OF AMERICA B-OPTICAL PHYSICS, 25 (8): 1380-1386 AUG 2008 Abstract: We fabricated a series of glasses with the composition 94.7-XGeO2-5Al(2)O(3)-0.3Bi2O3-XPbO (X= 0-24 mol. %). Characteristic absorption bands of bismuth centered at 500, 700, 800, and 1000 nm were observed. Adding PbO was found to decrease the strength of bismuth absorption. The addition of 3%-4% PbO resulted in a 50% increase in lifetime, a 20-fold increase in quantum efficiency, and a 28-fold increase in the product of emission cross section and lifetime on the 0% PbO composition. We propose that the 800 nm absorption band relates a different bismuth center than the other absorption bands. (C) 2008 Optical Society of America. Optic Communication 240. An optically powered, free space optical communications receiver Liu, Jingjing (Department of Engineering Science, University of Oxford); Faulkner, Grahame E.; Collins, Steve; O'Brien, Dominic C.; Elston, Steve J. Source: Proceedings - IEEE International Symposium on Circuits and Systems, 2008 IEEE International Symposium on Circuits and Systems, ISCAS 2008, 2008, p 197-200 ISSN: 0271-4310 CODEN: PICSDI Conference: 2008 IEEE International Symposium on Circuits and Systems, ISCAS 2008, May 18-21 2008, Seattle, WA, United States Publisher: Institute of Electrical and Electronics Engineers Inc. Abstract: Two of the key components of sensor motes are a power source and a communications receiver. One approach to creating very small motes is to use free space optical communication and to scavenge power from the optical downlink. In this paper photodiodes are described that were made on a standard CMOS process and generate electrical 最新文献报导 64 XIOPM latest Documents Report power from the downlink beam. These photodiodes can be used to power the optical receiver that converts the modulation on the downlink to a bit stream. ©2008 IEEE. (4 refs.) 241. All-optical pulse processing for advanced photonic communication system Barry, L.P. (Research Institute for Network and Communications Engineering, DCU); Bondarczuk, K.; Dexter, K.J.; Maguire, P.J.; Reid, D.A.; O'Dowd, J.; Guo, W.H.; Lynch, M.; Bradley, A.L.; Donegan, J.F. Source: Proceedings of 2008 10th Anniversary International Conference on Transparent Optical Networks, ICTON, v 2, Proceedings of 2008 10th Anniversary International Conference on Transparent Optical Networks, ICTON, 2008, p 92-95 Conference: 2008 10th Anniversary International Conference on Transparent Optical Networks, ICTON, Jun 22-26 2008, Athens, Greece Sponsor: INTRACOM TELECOM Publisher: Institute of Electrical and Electronics Engineers Computer Society Abstract: This paper investigates the use of a Two-Photon Absorption photodetector for high speed processing of ultrashort optical pulses in advanced photonic communication systems. Specifically the paper describes how the TwoPhoton Absorption photodetector maybe employed for chromatic dispersion monitoring in high-speed, wavelength division multiplexed networks, and also for reducing multiple access interference noise in an optical code division multiplexed system. © 2008 IEEE. (10 refs.) 242. 1V supply CMOS DEMUX FOR 40-GB/S optical communication systems Liang, Bangli (Department of Electronics, Carleton University); Kwasniewski, Tad; Chen, Dianyong; Wang, Bo; Cheng, Dezhong Source: 24th Biennial Symposium on Communications, BSC 2008, 24th Biennial Symposium on Communications, BSC 2008, 2008, p 154-157 ISBN-10: 142441945X Conference: 24th Biennial Symposium on Communications, BSC 2008, Jun 24-26 2008, Kingston, ON, Canada Publisher: Institute of Electrical and Electronics Engineers Computer Society Abstract: A 1V supply 1:2 demultiplexer (DEMUX) based on 0.13μm CMOS technology is presented. It is designed for 40-Gb/s optical communication systems. This DEMUX achieved by a pair of master-slave flip-flops (MS-FFs) with opposite clock can operate at 40-Gb/s and beyond. Fully differential current mode logic (CML) is adopted to improve the bit rate of non-return-to-zero (NRZ) data stream and to suppress common mode disturbances. Output buffers for two outputs are employed to drive the external 50Ω loads. On-chip shunt peaking (SP) inductors are used to boost the bandwidth. Stacked current source combined with low V T (LVT) and regular VT (RVT) NMOS is used so that the proposed DEMUX has good immunity against possible process, voltage and temperature (PVT) variations. This DEMUX IC dissipates a total current of 25mA under a 1V supply and consumes a chip area of 0.54mm2 with bonding pads. (4 refs.) 243. Novel modulation format and high spectral efficiency technology for coherent optical communication systems Nakazawa, Masataka (Research Institute of Electrical Communication, Tohoku University) Source: LEOS Summer Topical Meeting, 2008 IEEE/LEOS Summer Topical Meetings, 2008, p 111-112 ISSN: 1099-4742 Conference: 2008 IEEE/LEOS Summer Topical Meetings, Jul 21-23 2008, Acapulco, Mexico Publisher: Institute of Electrical and Electronics Engineers Inc. Abstract: Recent progress on coherent transmission aiming a high spectral efficiency is described, focusing on a polarization-multiplexed 1 Gsymbol/s, 128 QAM transmission. A 14 Gbit/s data signal can be transmitted within an optical bandwidth of 1.4 GHz. © 2008 IEEE. (11 refs.) 244. Future broader-bandwidth optical communication systems Willner, Alan E. (University of Southern California) Source: LEOS Summer Topical Meeting, 2008 IEEE/LEOS Summer Topical Meetings, 2008, p 137-138 ISSN: 1099-4742 Conference: 2008 IEEE/LEOS Summer Topical Meetings, Jul 21-23 2008, Acapulco, Mexico Publisher: Institute of Electrical and Electronics Engineers Inc. Abstract: This paper will highlight various optical transmissions issues that might be critical for future 100-Gbit/s and 1Tbit/s Ethernet systems. Topics will include: spectral efficiency, advanced modulation formats, combating impairments, data granularity, and performance monitoring. © 2008 IEEE. (2 refs.) 最新文献报导 65 XIOPM latest Documents Report 245. History of coherent optical communication and challenges for the future Kikuchi, Kazuro (Department of Frontier Informatics, University of Tokyo) Source: LEOS Summer Topical Meeting, 2008 IEEE/LEOS Summer Topical Meetings, 2008, p 107-108 ISSN: 1099-4742 Conference: 2008 IEEE/LEOS Summer Topical Meetings, Jul 21-23 2008, Acapulco, Mexico Publisher: Institute of Electrical and Electronics Engineers Inc. Abstract: This paper reviews the 30-year history of coherent optical communication systems. We next discuss the stateof-the-art technology of the modern digital coherent receiver, which has been developed recently, and finally describe challenges for the future. © 2008 IEEE. (16 refs.) 246. Discrete multitone for novel application areas of optical communications Lee, S.C.J. (COBRA Research Institute, Technical University of Eindhoven); Walewski, J.W.; Randel, S.; Breyer, F.; Van Den Boom, H.P.A.; Koonen, A.M.J. Source: LEOS Summer Topical Meeting, 2008 IEEE/LEOS Summer Topical Meetings, 2008, p 163-164 ISSN: 1099-4742 Conference: 2008 IEEE/LEOS Summer Topical Meetings, Jul 21-23 2008, Acapulco, Mexico Publisher: Institute of Electrical and Electronics Engineers Inc. Abstract: Discrete multitone (DMT) is a spectral-efficient multicarrier modulation technique, derived from the more general orthogonal frequency division multiplexing. In this paper, the use of DMT in novel optical communication applications such as wireless visible light communication and plastic optical fiber links is presented and discussed. © 2008 IEEE. (5 refs.) 247. Wavelength tunable lasers in future optical communication systems Anandarajah, P.M. (Research Institute for Networks and Communications Engineering, Dublin City University); Kaszubowska, A.; Maher, R.; Barry, L.P. Source: Proceedings of 2008 10th Anniversary International Conference on Transparent Optical Networks, ICTON, v 2, Proceedings of 2008 10th Anniversary International Conference on Transparent Optical Networks, ICTON, 2008, p 109 Conference: 2008 10th Anniversary International Conference on Transparent Optical Networks, ICTON, Jun 22-26 2008, Athens, Greece Sponsor: INTRACOM TELECOM Publisher: Institute of Electrical and Electronics Engineers Computer Society Abstract: Monolithic tunable lasers (TL) have been an important component in dense wavelength division multiplexed (DWDM) systems mainly because of their ability to reduce inventory costs associated with different part numbers for fixed wavelength distributed feedback (DFB) lasers. Moreover, the use of wavelength agile laser diodes in DWDM networks has gained a lot of interest in recent years, due to emerging new applications such as optical switching and routing, which require fast switching lasers in the nanosecond regime [1,2]. Employment of such lasers as tunable transmitters in wavelength packet switched (WPS) networks is one of the possible applications of these devices. In such systems, the information to be transmitted could be encoded onto a destination dependent wavelength and the routing of traffic could be performed on a packet-by-packet basis. The utilization of TLs in an optical switching and routing environment would put stringent requirements on its performance. This would include increased tuning range, high side mode suppression ratio (SMSR), reduced switching time and excellent wavelength stability. The sampled-grating distributed Bragg reflector (SG DBR) TL proves to be an ideal candidate, due to its large tuning range (40 nm), high output power (10 dBm), high side mode suppression ratio (SMSR > 30 dB) and simplicity of integration. In this paper we focus on some of the most important aspects of TL performance (switching speed, settling time, wavelength stability etc.) with respect to its possible application in high-speed optical wavelength packet switched networks. The device under test (DUT) is a fast wavelength tuning Sampled Grating Distributed Bragg Reflector (SG-DBR) supplied by Intune Networks. This device is capable of switching between any set of 50 GHz spaced ITU channels, within the conventional (C) band, with a 200 ns switching time and 200 ns settling time. Another aspect of TL operation examined, in order to verify its usefulness for short reach applications, is its performance under direct modulation. As the demand for broadband connectivity increases, it is expected that tunable lasers will be employed in metro and access networks within DWDM systems. Such systems would be able to provide significant capacity to many users. However, market adoption of such a solution would be based on its cost efficiency. A solution to this cost cutting measure could be achieved by adopting the technique of direct modulation, which is one of the most simple and efficient ways to modulate the lightwave signal. (2 refs.) 248. Programmable pulse shaping by using Liquid Crystal-Spatial Light Modulator (LC-SLM) for optical wireless communications 最新文献报导 66 XIOPM latest Documents Report You, S. (Center for Information and Communications Technology Research (CICTR), Department of Electrical Engineering, Pennsylvania State University); Kavehrad, M. Source: Canadian Conference on Electrical and Computer Engineering, IEEE Canadian Conference on Electrical and Computer Engineering, Proceedings, CCECE 2008, 2008, p 309-312 ISSN: 0840-7789 CODEN: CCCEFV Conference: IEEE Canadian Conference on Electrical and Computer Engineering, CCECE 2008, May 4-7 2008, Niagara Falls, ON, Canada Publisher: Institute of Electrical and Electronics Engineers Inc. Abstract: We demonstrated programmable optical pulse shaping of femto-second laser pulse by using Liquid CrystalSpatial Light Modulator (LC-SLM). With a combination of amplitude and phase mask in LC-SLM, arbitrarily shaped ultra-short pulse waveforms could be synthesized by manipulating the frequency components which are spatially dispersed in the high-resolution zero-dispersion pulse shaping system. The specified shaped pulses, Square Root Raised Cosine (SRRC) and Meyer wavelet, are generated through the programmable pulse shaping system, which can potentially improve the performance of optical wireless communication system, for transmission through clouds. © 2008 IEEE. (17 refs.) 249. Diversity gain analysis of free-space optical communication systems Safari, Majid (Department of Electrical and Computer Engineering, University of Waterloo); Uysal, Murat Source: Canadian Conference on Electrical and Computer Engineering, IEEE Canadian Conference on Electrical and Computer Engineering, Proceedings, CCECE 2008, 2008, p 1239-1244 ISSN: 0840-7789 CODEN: CCCEFV Conference: IEEE Canadian Conference on Electrical and Computer Engineering, CCECE 2008, May 4-7 2008, Niagara Falls, ON, Canada Publisher: Institute of Electrical and Electronics Engineers Inc. Abstract: In this paper, we present a diversity gain analysis for free-space optical (FSO) diversity systems operating in log-normal atmospheric turbulence channels. We consider a multi-input multi-output (MIMO) system and two decodeand-forward (DF) relay-assisted systems based on either serial (i.e., multi-hop transmission) or parallel (i.e., cooperative diversity) configurations. We adopt the recently introduced so-called "asymptotical relative diversity order" (ARDO) in our analysis and derive ARDOs for FSO diversity systems under consideration. Assuming M transmit and N receive apertures in MIMO scheme, we demonstrate that an ARDO of 4σ2x/ln(1 + (exp(4σ2x)-1)/MN) is achievable where σ2x is the variance of the fading logamplitude. For weak turbulence conditions (i.e., σx [similar to] 0.1), ARDO is well approximated as MN. For DF relaying schemes with K relays each of which is equipped with single transmit/receive apertures, we demonstrate that ARDOs of (K + 1)11/6 and 211/6 K are achievable, respectively, for serial and parallel relaying configurations. © 2008 IEEE. (12 refs.) 250. Blind detection of on-off keying for free-space optical communications Riediger, M.L.B. (Department of Electrical and Computer Engineering, University of British Columbia); Schober, R.; Lampe, L. Source: Canadian Conference on Electrical and Computer Engineering, IEEE Canadian Conference on Electrical and Computer Engineering, Proceedings, CCECE 2008, 2008, p 1361-1364 ISSN: 0840-7789 CODEN: CCCEFV Conference: IEEE Canadian Conference on Electrical and Computer Engineering, CCECE 2008, May 4-7 2008, Niagara Falls, ON, Canada Publisher: Institute of Electrical and Electronics Engineers Inc. Abstract: We investigate blind detection, i.e. detection assuming the absence of instantaneous channel state information (CSI) and a statistical channel description at the receiver, of on-off keying (OOK) in a free-space optical (FSO) system. Using an observation window encompassing many consecutive independent bits, our blind detector capitalizes on the fact that the atmospheric turbulence is constant over the observation window and that the expected number of transmitted 1s and 0s are equal. To improve receiver performance beyond that of the initial blind detector, we also consider the use of decision-aided threshold estimation and a second detection stage, respectively. Provided that a sufficiently large observation window is employed, simulation results indicate that the proposed receiver can attain performance comparable to that of the lower performance bound given by detection with CSI. © 2008 IEEE. (11 refs.) 251. Mitigation of turbulence-induced scintillation noise in free-space optical communication links using Kalman filter Chunyi, Chen (Key Lab. of Min. of Educ. for Photoelectric Measuring and Contr. and Optical Info. Transf. Technol., Changchun University of Science and Technology); Huamin, Yang; Huilin, Jiang; Jingtao, Fan; Cheng, Han; Ying, 最新文献报导 67 XIOPM latest Documents Report Ding Source: Proceedings - 1st International Congress on Image and Signal Processing, CISP 2008, v 5, Proceedings 1st International Congress on Image and Signal Processing, CISP 2008, 2008, p 470-473 Conference: 1st International Congress on Image and Signal Processing, CISP 2008, May 27-30 2008, Sanya, Hainan, China Publisher: Institute of Electrical and Electronics Engineers Computer Society Abstract: Atmospheric turbulence causes fluctuation of the received light signal in free-space optical (FSO) communication links through atmosphere, impairing link performance. The propagation of light wave in atmospheric turbulence was studied, and the received signal was modeled. Then the optimum decision threshold model was derived for FSO communication links using intensity modulation with direct detection (IM/DD). The turbulence-induced signal fluctuation, i.e. scintillation noise, was modeled as multiplicative noise in the received signal. In order to mitigate the scintillation noise, an adaptive Kalman filter was used to predict the value of received signal and turbulence statistics. Based on the Kalman filter, the detection with adaptive decision threshold was realized. Finally, the performance of Kalman filter was calculated, and the results show the error between optimum decision threshold and adaptive decision threshold is smaller than 0.48%. Kalman filter is an effective tool to combat turbulence-induced scintillation noise. © 2008 IEEE. (10 refs.) 252. Channel modeling in wireless optical communications using Markov chains Hajjarian, Zeinab (Department of Electrical Engineering, Pennsylvania State University); Kavehrad, Mohsen Source: Canadian Conference on Electrical and Computer Engineering, IEEE Canadian Conference on Electrical and Computer Engineering, Proceedings, CCECE 2008, 2008, p 2051-2055 ISSN: 0840-7789 CODEN: CCCEFV Conference: IEEE Canadian Conference on Electrical and Computer Engineering, CCECE 2008, May 4-7 2008, Niagara Falls, ON, Canada Publisher: Institute of Electrical and Electronics Engineers Inc. Abstract: Wireless optical communications is an attractive solution for the so-called "last-mile" problem due to the everincreasing demand for highspeed communications, and the difficulty of installing cable and optical fiber. In the presence of atmospheric phenomena such as cloud, fog, and turbulence the wireless optical communications channel happens to be time varying and dispersive, required to be accurately modeled. In most of the previous works, Monte-Carlo Ray Tracing (MCRT) algorithm has been used to measure channel parameters, though this algorithm needs a high computational capacity and a long execution time. We show that by modeling the photon trajectory in space by a Markov chain, angular dispersion can be calculated via matrix multiplications. We show that Markov chain model produces values that are close to MCRT algorithm results. © 2008 IEEE. (7 refs.) 253. Optical proximity communication using reflective mirrors Zheng, Xuezhe (Sun Microsystems Inc.); Cunningham, John E.; Shubin, Ivan; Simons, John; Asghari, Mehdi; Feng, Dazeng; Lei, Hongbin; Zheng, Dawei; Liang, Hong; Kung, Cheng-Chih; Luff, Jonathan; Sze, Theresa; Cohen, Danny; Krishnamoorthy, Ashok V. Source: Optics Express, v 16, n 19, Sep 15, 2008, p 15052-15058 Publisher: Optical Society of America Abstract: Optical proximity communication (OPxC) with reflecting mirrors is presented. Direct optical links are demonstrated for silicon chips with better than -2.5dB coupling loss, excluding surface losses. OPxC is a true broadband solution with little impairment to the signal integrity for high-speed optical transmission. With wavelength division multiplexing (WDM) enabled OPxC, very high bandwidth density I/O, orders of magnitude higher than the traditional electrical I/O, can be achieved for silicon chips. © 2008 Optical Society of America. (20 refs.) 254. Techniques for electronic mitigation of transmission impairments in fiber-optic communication systems Hellerbrand, Stephan (Institute for Communications Engineering, Technische Universitat Munchen); Hanik, Norbert Source: Proceedings of 2008 10th Anniversary International Conference on Transparent Optical Networks, ICTON, v 1, Proceedings of 2008 10th Anniversary International Conference on Transparent Optical Networks, ICTON, 2008, p 182-185 Conference: 2008 10th Anniversary International Conference on Transparent Optical Networks, ICTON, Jun 22-26 2008, Athens, Greece Sponsor: INTRACOM TELECOM Publisher: Institute of Electrical and Electronics Engineers Computer Society Abstract: In the following, we will give an overview of some transmitter and receiver side techniques for the mitigation of Chromatic Dispersion (CD), Polarization-Mode Dispersion (PMD) as well as intrachannel nonlinear effects. These include electronic predistortion as well as probabilistic receiver-side mitigation using Maximum Likelihood Sequence 最新文献报导 68 XIOPM latest Documents Report Estimation (MLSE). Particular emphasis is laid on the implementation complexity of the aforementioned techniques. © 2008 IEEE. (11 refs.) Large Aperture Mirror 255. Optical design of large aperture segmented mirror system Deng, Jian (Research Center for Space Optical Engineering, Harbin Institute of Technology); Zhang, Wei; Long, FuNian Source: Guangxue Jingmi Gongcheng/Optics and Precision Engineering, v 16, n 1, January, 2008, p 29-34 Language: Chinese ISSN: 1004-924X CODEN: GJGOF4 Publisher: Chinese Academy of Sciences Abstract: Based on balancing aberration of Three Mirror Anastigmatic (TMA), a kind of segmented optical design way with long focal length and wide Field of View (FOV) was introduced. Segmented system was completely simulated and analyzed using Fresnel diffraction integral for the exit pupil wavefront. Considering on the error analysis and distribution of non sequential surface, the initial design was modified. In order to balance the aberration and increase the system redundancy, the high order asphere and bigger aperture system were optimized. A segmented synthetic aperture optical system with segmented primary mirror was designed in EFL of 44 m, f/8, FOV of 0.6° × 0.06°. By iterating the design scheme and analyzing error, a good design is obtained. (15 refs.) 256. Large-aperture lightweight primary mirror design method using topology optimization Li, Yan-Wei (Changchun Institute of Optics, Fine Mechanics and Physics, Chinese Academy of Sciences); Yang, HongBo; Geng, Qi-Xian; Liu, Xiao-Bo; Lei, Cheng-Hua Source: Guangxue Jishu/Optical Technique, v 34, n 2, March, 2008, p 236-238 Language: Chinese ISSN: 1002-1582 CODEN: GJISEP Publisher: Optical Technique Abstract: Using topology optimization, a new method of lightweight mirror is put forward, with strong theory and high efficiency. The continuum structure topological optimization mathematical model is created with the variable-density method. By means of OPTISTRUCT software, the maximum deformation of the surface of primary mirror under the gravity and the first model frequency are assigned to response variable, the entire volume of mirror is converted to object function. According to the topological structure, the optimum lightweight mirror is built satisfying the wave front error and the structural stiffness and the ratio of weight, considering structural mechanics and sensitivity analysis. (5 refs.) 257. Design of large aperture mirror support and its stability Fu, Xue-Nong (Institute of System Engineering, China Academy of Engineering Physics); Chen, Xiao-Juan; Wu, WenKai; Xu, Yuan-Li Source: Guangxue Jingmi Gongcheng/Optics and Precision Engineering, v 16, n 2, February, 2008, p 179-183 Language: Chinese ISSN: 1004-924X CODEN: GJGOF4 Publisher: Chinese Academy of Sciences Abstract: On basis of the schemes of adjustable kinematic mounts and integrative design, a large aperture mirror support for the target area of Inertial Confinement Fusion (ICF) facility was analyzed to solve some problems on stability, exact constrain, fast installation and easy adjustment. Then the structure characteristic and mechanical analysis were introduced, and the experiment of sample confirms feasibility of the design. Analysis and experimental results indicate that the sample satisfies the requirement for system's stability, the accuracy of orientation and relocation of the mount is less than 10μrad. (5 refs.) 258. Preliminary analysis and experiment of thermal influence on a large aperture mirror Hu, Wei-Jie (Optical Engineering Dept., Beijing Institute of Technology); Xu, Peng-Mei; Zhang, Hua-Peng; Zhao, Lei; Bian, Guang-Chun; Yu, Xin; Hu, Xin-Qi Source: Proceedings of SPIE - The International Society for Optical Engineering, v 6834, Optical Design and Testing III, 2008, p 68342R ISSN: 0277-786X CODEN: PSISDG Conference: Optical Design and Testing III, Nov 12-15 2007, Beijing, China Sponsor: Society of Photo-Optical Instrumentation Engineers (SPIE);Chinese Optical Society (COS) 最新文献报导 69 XIOPM latest Documents Report Publisher: SPIE Abstract: Thermal distortion of the optical elements can greatly reduce the high resolution of the space-borne camera. The general thermal effect on mirror is analyzed and the optical aberration of the optical surface resulting from 3 kinds of thermal gradient is discussed. The thermal distortion simulating experiment of a large aperture flat mirror is designed and the optical aberration is tested on 18'' ZYGO with the different axial thermal disturb. The testing results conclude that the small thermal gradient can greatly affect the wave-front, the aberration of this large aperture flat mirror can be used to simulate the thermal distortion on space, and MTF is also reduced greatly when this large aperture flat mirror is used in the real space-borne camera under the same thermal environment. In order to correct the thermal distortion and keep the high resolution, the 37-units adaptive optics correction close loop experiment is designed and installed in the above camera. The correction results show that MTF of the testing camera will not reduced greatly under the large thermal distortion. So employing adaptive optics on a high resolution space camera is the necessary and the valid method to correct the thermal distortion. (7 refs.) 259. Optimization and analysis of active support technology of thin mirror with large aperture Feng, You-Jun (College of Electronics and Information Engineering, Sichuan University); Zhang, Rong-Zhu Source: Qiangjiguang Yu Lizishu/High Power Laser and Particle Beams, v 20, n 2, February, 2008, p 239-243 Language: Chinese ISSN: 1001-4322 CODEN: QYLIEL Publisher: Editorial Office of High Power Laser and Particle Beams Abstract: A one-dimension analysis model was set up to describe the thin mirror deformation process caused by discrete external forces, especially with small bending approximating. With the model, a thin mirror with a diameter of 300 mm and a ratio of 40 of diameter to thickness at discrete supports is simulated by finite element analysis method and four different deformations are calculated. The external concentrated forces can be obtained from the analysis results. During the optimization process, the location and the magnitude of external forces are determined by zero order optimization method. The optimization analysis results show that the deformation curve with optimization corresponds to the target curve. The maximum average difference decreases as much as 58%, compared with the results without optimization. (8 refs.) 260. Application of low-coherence-source interferometric system to phase error detection of segmented primary mirrors for large-aperture telescope Song, Helun (Institution of Optics and Electronics, Chinese Acad. of Sci.); Li, Huaqiang; Xian, Hao; Yang, Ruofu; Huang, Jian; Jiang, Wenhan Source: Guangxue Xuebao/Acta Optica Sinica, v 28, n 8, August, 2008, p 1523-1526 Language: Chinese ISSN: 0253-2239 CODEN: GUXUDC Publisher: Chinese Optical Society Abstract: For the large aperture telescope with segmented primary mirrors, a low-coherence-source interferometric detection system based on the Michelson interferometric principle was put forward to detect the phase error between the segmented mirrors, correct the misaligned segments and achieve the mirror coplanar. The concrete structure of the interferometric detection system with the low-coherence source was presented, and the detection principle of the interferometric detection system was narrated. Double-center-wavelength combination low-coherence-source light sources were applied to detecting the phase error of the segmented mirrors and the minimum signal-to-noise ratio was analyzed. The result shows that the application of the double-central-wavelength combination low-coherence source light sources system largely raises the ability of signal distinguishing of the center fringe of the interferograms, improves the measurement accuracy, and makes the low-coherence-source interferometric detection system extract the phase error with high precision. (13 refs.) 最新文献报导 70