Quality Control Devices
Pro.Dr.Cao Congjun
Xi’an university of Technology
P274-291
Insert 7-8
测控条的测控原理

测控条(Quality control strip/target)：由
网点、实地、线条等测标组成的用于判断
和控制拷贝、晒版、打样和印刷时信息转
移状况的软片条。
1. 网点面积的扩大与网点边缘长度总和成正比。
线数高时，总边长大，网点扩大值越大。
用于检测网点扩大值。
e.g. Brunner 50%粗网和50%细网/ GATF字码信号条
2. 用几何图形位置相等、阴与阳相反等原理控制网点
大小和形状。
e.g. Brunner阴阳十字线和阴阳网点
3. 边缘增大条件下，角度处比弧度出变化更敏感。
e.g. GATF星标、放射楔形线
4. 利用50%面积的等宽折线控制不同方位的变化。
e.g. Brunner 50%细网段的折线
5. 用等宽线的同心圆控制任意方位的变形。
e.g. GATF星标、放射楔形线
GATF-the Graphic Arts Technical
Foundation
The GATF T-Mark consists of a configuration of thin,
accurately ruled lines that are used to identify image
centers, folds, trims, and bleeds during printing
production (figure 12.16).
The GATF Star Target is a small, circular pattern of
solid and clear pie-shaped wedges (figure 12.17).
When printed on a press sheet,the Star Target gives
the press operator a quick and effective measure of
ink spread,slur,and doubling (figure 12.18).

Ink spread: Spreading in all directions of the
edges of ink dots and lines on the press
sheet beyond their corresponding areas on
the plate.
Doubling:Printing of a double
image, which consists of a full
solid and a weak second
image slightly out of register
with the full solid.
Slur:Smearing拖尾
of
the trailing edges of
dots,resulting in ink film
tapering逐渐减少 into the
white areas.
Dot Gain
The GATF Quality Control Strip


The GATF Quality Control (QC) Strip is a
patterned devices that helps the press
operator control print quality throughout the
press run.
OK sheet
The GATF Dot Gain Scale and Slur
Gauge
The GATF Dot Gain Scale is designed to give
numerical values to any dot sharpening or dot
gain,The scale is made up of ten 200-line
screen tint steps which are graduated in density.
These steps form numbers from 0 to 9 on a
uniform background of 65-line tint density.
Testform测试版


A test form is a comprehensive diagnostic and
measurement tool designed to help the printer achieve
higher quality color printing with less waste and reduced
make-ready time.
GATF test forms contain a variety of quality control
targets in addition to color reproduction targets. The
quality control targets can be divided into three
categories according to their use: diagnostic targets,
process control targets, and standardization targets.
Although some quality control targets can be used for
more than one purpose, the functions remain distinct.

• Diagnostic Targets are used to troubleshoot printing
systems
Ladder Bars
Star Targets

• Process Control Targets are used to monitor the
printing system
Color Control Bar
Tone Scales
Vignettes[vinjet] 小插图
Color Reproduction Guides

• Standardization Targets are used to measure the
attributes of the printing system
Gray Balance Chart
Ink Coverage Chart
Print test form
Print test form
Ink Trapping Target
Color Bar & Solid Strip
Gray balance Target
Register Target
Homework

P292 Review questions 6,14.