May, 2009
Our featured LCI Faculty this month is Professor Deng-Ke Yang. His Profile can be found at the end of
the newsletter, following LCI NEWS. Student CVs can be accessed on the IPP website,
http://ipp.lci.kent.edu by clicking the “LCI Connection” tab.
This month’s newsletter also provides a “how to” section about a method to build a driver for a
multipixel liquid crystal device.
CLEANROOM NEWS
This summer, LCI cleanroom staff will continue with room reorganization plans and attempt to return
several pieces of equipment to proper working condition.
The MRC sputter coater located on the 1st floor (“MRC Room”) has undergone routine maintenance to
tune the RF power supply output, and to clear blockages in the cooling water lines. The unit is currently
running using a slightly undersized mechanical pump while the larger pump is rebuilt. This pump is
expected to be returned in June, but the MRC is completely operational now, for the usual nickel or
SiO2 coatings.
The new high end assembly area has been completed, in the alcove next to the cleanroom air shower.
The Asymtek A402 XY Dispenser has been reinstalled in this space (the A403 Dispenser is still in the
original assembly area), and the Fusion UV Source and Dymax UV Source have been moved to this
area as well. This area will initially be used by one of the IPP member companies for more complicated
assembly tasks.
Parts are expected in the next 1-2 weeks to complete installation of an Ocean Optics Spectrometer in
the standard assembly area. This would allow for quick cell gap measurements during and immediately
after cell assembly efforts. Completion of this setup is expected in June.
The Brewer GX100 Large Area Spincoater has been shipped back to Brewer for repairs and upgrades,
and is expected to be completely reinstalled in the next 2-3 weeks. The unit will be returned to
operating condition, but will continue to operate with some components that are obsolete. At this time,
the cost of completely upgrading the unit to supported hardware is not justified, especially with the
Headway Research IT22 Spincoater also available.
The GenVac Aerospace SC1 ion-assisted e-beam coater is currently operational for metal or insulator
coatings, but not for ITO. GenVac has agreed to help troubleshoot and repair the custom ion gun. One
of the turbo pump controllers requires repair as well. The ion gauges have been replaced, and staff will
continue to look at upgrading the safety interlocks, likely in late June or early July, depending upon
interest in the machine.
If there are particular pieces of equipment that are of interest to you, or if you would like to see
particular capabilities added to the room, please contact Doug Bryant.
MULTI-PIXEL LIQUID CRYSTAL DEVICE DRIVER
To drive an LCD requires a RMS voltage, which from the viewpoint of the torque on the liquid crystal
director could be a straight DC voltage from a battery. But there are ions present in the liquid crystal
material that migrate under the influence of a DC voltage and cause problems. (may be the subject of
another note). So the drive voltage requirement is typically a balanced AC square wave. The value of
the RMS level can be changed by changing the amplitude of the square wave, or by adjusting its duty
cycle. For fast responding devices, this second method can cause a ripple in the optical response, so it
is not the method we will consider here.
As a result of the above considerations, to drive a typical LCD pixel requires an AC balanced square
wave with a variable amplitude that typically covers the range from 0 to 5 or 10 volts. The frequency is
not too critical, but a value of 1kHz is generally fast enough to eliminate most ion problems, and also is
not too high to run into RC time constant issues associated with the capacitance of the cell and the
resistance of the driver, the connection to the LC device, and the transparent conductive electrodes on
the device.
To drive a single pixel, it is convenient to use a lab signal generator, but if many pixels are needed to be
driven with different voltages, this is not a convenient solution.
Merrill Groom, our EE at the LCI, has found that analog output cards are available from National
Instruments or UEI can provide a good solution for a multi-pixel driver.
We used National Instruments hardware and software because we are familiar with it. Their analog
output hardware can seen by logging onto (http://www.ni.com) and going to Products & Services ->
(Shop Hardware) -> Data Acquisition -> (Analog Output Channels). Next, search their product matrix
for the desired Form Factor, Analog Output Range, Operating system etc. For example, selecting a
“PCI” form factor on the parametric search turned up six analog output cards that may work in our
application. Another analog output board manufacturer to consider is United Electronics Incorporated
(UEI). They sell several high channel count analog output boards and may be found at
(http://www.ueidaq.com). Searching under Products -> I/O Type -> Analog Output -> PCI/ISAS Bus
turns up seven boards. Go to specifications and accessories for a list of support hardware and software.
For software, we used the National Instruments LabVIEW graphical programming suite to control our
NI analog card. But, as long as the appropriate driver module is available, LabVIEW can control any
manufacturer’s hardware. Mathwork’s Matlab is another object oriented software packages, running in
the Windows, Unix or Linyx environment, that can be used to control NI, UEI or other manufacturer’s
hardware. Go to (http://www.mathworks.com) and navigate to Products and Services -> Test &
Measurement -> Supported Hardware for a list of manufacturers of hardware that they support. The
National Instruments page at the Matlab site is:
http://www.mathworks.com/products/daq/supportedio14005.html
For a recent application, we used a National Instruments 32 channel Digital to Analog board with a PCI
form factor. All of the code necessary to drive the analog board is supplied with the board and we used
the LabVIEW development suite to generate the user interface. Once the user interface is written and
compiled, the development suite is not needed and the display driver can be operated with only the
runtime engine installed a personal computer. Small DA boards are available for use with laptop
computers but typically they only have 16 channels of output.
Specifically, we used a National Instruments NI 6723-68 DAQ board. This board offers 32 channels of
analog output and a variety counter/timers and digital I/O. Because of this board’s two high density
connectors (68 pins per), cabling was difficult. Such high density connectors are designed for machine
crimping flat ribbon cable. Factory made cables for this board have 68 signal wires, plus shielding,
gathered into a relatively large and stiff bundle. This analog board has two 68 pin connectors with output
and input lines distributed over both connectors thus requiring two such cables. In our application, we
chose to manually crimp individual wires with the aid of a microscope. Using the high density
connectors but manually crimping allowed the use of a single lightweight flexible ribbon cable with the
exact numbers of wires needed. Interconnects are one of the least considered and most frustrating aspect
of such driver system. When planning such systems, interconnects should be considered early on in the
design process.
In a subsequent newsletter, we will cover an approach to connecting the driver to an LCD.
Details of this unit along with the software that we developed to run it, will be available in the next
month on from our website under the “Publications and Tutorials” tab.
LCI NEWS
Li secures research funding from AFOSR to develop light-driven chiral molecular motors and
novel functionalized hybrid gold nanorods
LCI Senior Research Fellow, Dr. Quan Li, has secured research funding from the Air Force Office of
Scientific Research for two five-year projects. A $625,000 award will support a project on the
development of light-driven chiral molecular motors and an additional $750,000 will support the
development of novel functionalized hybrid gold nanorods.
The Light-Driven Chiral Molecular Motors Project
Dynamic control of molecules by light is an important area of modern nanoscience. The team will focus
on synthesis and characterization of effective light-driven molecules that can be added to cholesteric
liquid crystals to create optically tunable materials and devices.
The Novel Functionalized Hybrid Gold Nanorods Project
As compared to their spherical counterparts, metallic nanorods offer a number of new opportunities,
ranging from materials science to biomedical applications. Assemblies of nanorods are considered as an
attractive pathway to prepare optical metamaterials, i.e. artificially engineered materials with unusual
optical properties and applications ranging from sub-wavelength imaging to cloaking. This project
contributes greatly to the expansion of LCI research into the new areas.
Fontana Awarded University Fellowship
Jake Fontana, CPIP graduate student, has been awarded a University Fellowship for the academic year
2009-2010.
Recent Events
KSU Spring 2009 Science Symposium
The Center for Materials Informatics hosted a science symposium on May 13 in the Samsung
Auditorium at the Liquid Crystal Institute. This interdisciplinary symposium focused on synthesis,
processing, characterization and applications of materials. The symposium consisted of 8 invited talks,
with presentations from each of the participating science departments, programs, institutes, and centers.
http://cmi.kent.edu/events/may_13_2009/event.php?i=1
Recent Publications
Professor Jonathan Selinger and CPIP Student Lena Lopatina recently published "Theory of
Ferroelectric Nanoparticles in Nematic Liquid Crystals," in Physical Review Letters, and it was selected
by the journal as an "Editors' Suggestion." The abstract states: “Recent experiments have reported that
ferroelectric nanoparticles have drastic effects on nematic liquid crystals—increasing the isotropicnematic transition temperature by about 5 K, and greatly increasing the sensitivity to applied electric
fields. To understand these effects, we develop a theory for the statistical mechanics of ferroelectric
nanoparticles in liquid crystals. This theory predicts the enhancements of liquid-crystal properties, in
good agreement with experiments. These predictions apply even when electrostatic interactions are
partially screened by moderate concentrations of ions.” PRL 102, 197802 (2009)
Recent LCI Seminar Videos Available
(Note: To see video recordings of these presentations, go to the IPP web site:
http://www.lci.kent.edu/ipp/07/lciconnection.htm and click on the “Access Videos” link and enter your
login and password.)
April 29, 2009 - Prof. Royce Zia, Department of Physics, Virginia Tech University, "New Surprises in
Driven Systems with Two Species"
April 22, 2009 - Prof. Michael Hu, Department of Marketing, Kent State University, "Artificial Neural
Networks, Strategic Alliances and Consumer Research"
April 15, 2009 - Prof. Hyuk Yu, Department of Chemistry, University of Wisconsin - Madison,
"Polymer Surface Functionalization and Endovascular MRI Applications"
April 13, 2009 - Prof. Rajeswari Kasi, Polymer Program, Institute of Materials Science & Chemistry
Department, University of Connecticut, "Self-Assembling Polymers: Ordering on Multiple Length
Scales"
April 6, 2009 - Prof. Wim H. de Jeu, Polymer Science & Engineering, University of Massachusetts,
Amherst, "On the Subtleties of Smectic Layer Ordering"
March 30, 2009 - Prof. Changhuei Yang, Bioengineering and Electrical Engineering, California
Institute of Technology, "Novel Optical Approaches for Biomedical Applications"
Upcoming Events and Conferences
Society for Information Display Week 2009 will be held May 31-June 5 in San Antonio, TX.
http://www.sid.org/conf/sid2009/sid2009.html
The Gordon Research Conference on Liquid Crystals will be held June 14-19 at Colby-Sawyer College
in New London, NH. http://www.grc.org/programs.aspx?year=2009&program=liqucryst
The 5th International Liquid Crystal Elastomer Conference will be held at the Liquid Crystal Institute on
September 24-26, 2009. http://ilcec2009.lci.kent.edu
FACULTY PROFILE
Deng-Ke Yang
Statement of Interest
My research interest is in liquid crystals and liquid crystal/polymer composites, particularly interested in
developing liquid crystal electro-optical devices, investigating interaction between liquid crystal and
polymer and exploring chiral liquid crystals.
Current Lab Activities
• Developing liquid crystal switchable goggles
• Developing liquid crystal switchable windows for privacy and energy flow control
• Developing cholesteric liquid crystal from biological materials
• Developing compensation films for large viewing angle LCDs
CV/website
• http://www.lci.kent.edu/PI/DkYang.htm
Research Interests
• Electro-optical liquid crystal devices
• Liquid crystal/polymer composites: physics and applications
Application interests
• Liquid crystal goggles
• Reflective liquid crystal display
• Flexible liquid crystal display
• Switchable window
• Large viewing angle liquid crystal display: compensation films and liquid crystal modes
Interests in potential industrial interactions
• Research / Development topics
I would be glad to collaborate with industrials in the following areas:
o Switchable liquid crystal goggle
o Switchable liquid crystal light shutter and window
o Reflective liquid crystal display
o Flexible liquid crystal display
o Modeling electro-optical properties of liquid crystal devices
o Lab facilities of potential interest to IPP members.
o My lab has capabilities for most aspects of the characterization of LC devices.
o Topics that could address as consultant
Current Postdoctoral Fellow and Graduate Students
• Young-Cheol Yang (Postdoc.)
• Shawn Hurley
• Sarah Hicks
• Rafael Zola
Awards
Information Display Society Special Recognition Award
For pioneering work on polymer stabilized devices and reflective displays, 2005.
Information Display Society Fellow
For significant scientific and technological contributions to bistable, reflective cholesteric displays and
to polymer-stabilized cholesteric devices, and for his outstanding contributions to education in the field
of liquid crystal technology, 2007.
Recent publications
Books
1. S.-T. Wu and D.-K. Yang, “Reflective liquid crystal displays,” John Wiley & Sons, Ltd., (2001).
2. D.-K. Yang and S.-T. Wu, “Fundamentals of liquid crystal devices,” John Wiley & Sons, Ltd.,
(2006).
Chapters in books
1. D.-K. Yang, L.-C. Chien and Y.K. Fung, "Polymer stabilized cholesteric textures: materials and
application,” in Liquid crystals in Complex Geometries Formed by Polymer and Porous Networks,
ed. G.P. Crawford and S. Zumer, Taylor & Francis, London (1996), Chapter 5, 103-143.
2. D.-K. Yang, X.Y. Huang and Y.-M. Zhu, "Bistable cholesteric reflective displays: Material and
Drive Schemes," Annual Review of Materials Science, 27, 117-222 (1996).
3. D.-K. Yang, “Reflective cholesteric liquid crystal displays,” in Mobile Displays, ed. A. Bhowmik,
Z. Li and P. J. Bos, John Wiley & Sons, Ltd., (2008), Chapter 16, 443-466.
Papers
1. D-K, Yang, “Flexible bistable cholesteric reflective displays,” J. Display Technology, 2, 32-37
(2006).
2. K.-U Jeong, D.-K. Yang, M. J. graham, Y. Tu, S.W. Kuo, B. S. Knapp, F. W. Harris and S. Z. D.
Cheng, “Construction of chiral propeller architectures from achiral molecules,” Advanced Materials,
18, 3229 (2006).
3. K.-U Jeong, A. J. Jing, B. Mansdor, M. J. Graham, D.-K. Yang, M. J. Graham, F. W. Harris and S.
Z. D. Cheng, “Biaxial molecular arrangement of rod-disc molecule under electric field,” Chemical
Materials, 19, 2921 (2007).
4. D.-K. Yang, Y. Yin and H. Liu, “Nematic-isotropic phase transition of binary liquid crystal
mixtures,” Liquid Crystals, 34, 605 (2007).
5. D.-K. Yang, “Review of operating principle and performance of polarizer free reflective liquidcrystal displays,” J. Soc. Inf. Display 16, 117 (2008).
6. D.-K. Yang, K.-U. Jeong, S. Z. D. Cheng, “Structure of Liquid Crystal Droplets with Chiral
Propeller Texture,” J. Phys. Chem. B, 112; 1358-1366 (2008).
7. F. Zhou and D.-K. Yang, “Design of transflective bistable twisted nematic LCD,” SID Intl Symp.
Digest Tech. Papers, XXXVII, 825-828 (2006).
8. D.-K. Yang, F. Zhou, S. Hurley and L. Shi, “An analytical approach in designing film STN LCDs,”
Conf. Rec. 26th Intl. Display Research Conference, 235-238 (2006).
9. D.-K. Yang, F. Zhou, S. Hurley and L. Shi, “An analytic approach in designing film STN LCDs,”
Conference Record of International Display Research Conference, 235-238 (2006).
10. S. Hurley and D.-K. Yang, Jianru Shi and Chris Mullin, “A Systematic Optimization of NormalWhite STN-LCDs,” SID Intl Symp. Digest Tech. Papers, XXXVIII, 475-478 (2007).
11. Y.-C. Yang and D.-K. Yang, “Achromatic reduction of off axis light leakage in LCDs by selfcompensated phase retardation (SPR) film,” SID Intl Symp. Digest Tech. Papers, XXXIX, 19551958 (2008).
12. S. Hicks, Y.-C. Yang and D.-K. Yang, “Stability and performance of OCB in transflective display,”
Conference Record of International Display Research Conference, 7-10 (2008).
13. S. Hurley, Y-C. Yang and D.-K. Yang, J. Shi and C. Mullin, “Driving dynamics of VA-LCDS with
small pretilt angles,” Conference Record of International Display Research Conference, 164-167
(2008).
14. Y.-C. Yang and D.-K. Yang, “Simulation study and design of biaxial nematic liquid crystal
displays,” Conference Record of International Display Research Conference, 179-182 (2008).
15. Y.-C. Yang and D.-K. Yang, “Achromatic reduction of light leakage in reflective LCDs by selfcompensated phase retardation (SPR) film,” Conference Record of International Display Research
Conference, 249-252 (2008).
Patents
1. "Color liquid crystal display consisting of polymer dispersed chiral liquid crystal having negative
dielectric anisotropy," P.P. Crooker and Deng-ke Yang, US. Patent 5,200,845, April 6, 1993.
2. "Method and Apparatus for Electronic Switching of a Reflective Color Display," D.K. Yang and
J.W. Doane, US. Patent 5,251,048, Oct. 5, 1993.
3. "Grey Scale Liquid Crystal Materials," D.K. Yang and J.W. Doane, US. Patent 5,384,067, June 24,
1995.
4. "Liquid Crystal Light Modulating Device and Material," D.K. Yang, J.W. Doane, and L.C. Chien,
US. Patent 5,437,811, Aug. 1, 1995
5. "Multistable Cholesteric Liquid Crystal Shutter," J.L. West and D.K. Yang, US Patent 5,453,863,
Sept. 26, 1995.
6. "Liquid Crystal Light Modulating Device and Material," D.K. Yang, J.W. Doane, and L.C. Chien,
US. Patent 5,695,682, December 12, 1997.
7. "Dynamic drive method and apparatus for bistable liquid crystal display," X.Y. Huang, D.-K. Yang
and P. Bos., U.S. Patent 5,748,277, May 5, 1998.
8. "Polymer stabilized bistable black-white cholesteric reflective display," R.Q. Ma and D.-K. Yang.
US. Patent 5,847,798, December 8, 1998.
9. "Bistable polymer dispersed cholesteric liquid crystal displays," D.-K. Yang, Z.-J. Lu and J.W.
Doane, US. Patent 6,061,107, May 9, 2000
10. "Dual frequency switchable cholesteric polarizer and the drive waveform," D.-K. Yang and M. Xu,
US. Patent 5,877,826, March 2, 1999.
11. "Drive schemes for gray scale bistable cholesteric reflective displays," Deng-Ke Yang, Xiao-Yang
Huang and Nick M. Miller, US Patent 6,268,839, B1, Jul. 31, 2001.
12. "Cumulative two phase drive scheme," D.-K. Yang and Y.M. Zhu, US Patent 6,204,835 B1, March
20, 2001.
13. "Dynamic drive methods and apparatus for bistable cholesteric display," D.-K. Yang, Y.-M. Zhu
and X.-Y. Huang, U. S. Patent 6,154,190, Nov. 28, 2000.
14. "Dual frequency cholesteric display and drive scheme," Ming Xu and Deng-Ke Yang, US. Patent
6,320,563 B1, November 20, 2001.
15. “Pressure sensitive liquid crystalline light modulating device and material,” J. W. Doane, D.-K.
Yang and L.-C. Chien, US. Patent 6,104,448, August 15, 2000.
16. “Polymer stabilized ECB transflective liquid crystal display,” D.-K. Yang and F.S. Zhou, pending.
17. “Bistable polymer stabilized cholesteric texture switchable window,” D.-K. Yang and L. Shi,
pending.
18. “Polymer stabilized isotropic liquid crystal display and phase modulator,” D-K. Yang, Y.-C. Yang
and B. Rui, pending.
Recent Short course and Talks
1. April 8, 2006, New Jersey SID chapter meeting, New Jersey, “Ch reflective displays: principle,
current status and future,” invited.
2. June 3, 2006, SID, San Francisco, Ca, “Design of Transflective Bistable Twisted Nematic LCD,”
poster.
3. June 9, 2006, SPIE, Dayton, Oh, “Dynamics of evolution of disclinations in cholesteric liquid
crystals,” Invited.
4. July 3, 2006, ILCC, Keystone, Co, “Interaction between different nematic liquid crystal molecules,”
Poster.
5. July 3, 2006, ILCC, Keystone, Co, “Ideal polarization convention in liquid crystal devices by
Mueller matrices and Poincaré sphere,” Poster.
6. July 3, 2006, ILCC, Keystone, Co, “Dynamics of evolution of pi-wall disclinations in cholesteric
liquid crystals,” poster.
7. July 13-18, 2006, JiaoTong University, Shanghai, China, 32 hours lecture, “Liquid crystal displays”
8. September 18. 2006, Kent, Ohio, USA, International Display Research Conference workshop,
“Reflective liquid crystal displays,” invited lecture.
9. September 22, 2006, Beijing, China, China Flat Panel Display annual conference, “Cholesteric
reflective LCD and other reflective LCDs,” Plenary lecture.
10. May 22, 2007, Long Beach, Ca, SID, “Systematic optimization of normal white STN liquid crystal
display,” Poster
11. June 13, 2007, New London, NH, Gordon conference on liquid crystals, “Simulation study of
droplets with propeller texture,” poster.
12. July 10, 2007, Advanced Polymer System, Inc., Akron, OH, “Compensation films for wide viewing
angle LCDs” invited.
13. October 8, 2007, Beijing University of Science and Technology, “Polymer stabilized liquid
crystals,” invited
14. October, 17, 2007, Shanghai, China, Asia Optical Fiber Communications and Optoelectronics
Exhibition and Conference,”Cholesteric reflective display: principle and progress,” invited.
15. October 30, 2007, XVI International Material Research Congress, Cancun, Mexico, “Polymer
stabilized liquid crystals and their applications,” Invited.
16. January 7, 2008, Jackson Safety Inc. Grand Rapids, MI, “Liquid Crystal technologies for switchable
goggle application”, invited.
17. February 27, 2008, Applied Materials, San Jose, Ca, “Reflective displays, liquid crystal reflective
displays and cholesteric display”, invited.
18. March 12, 2008, Shanghai, China, China annual flat panel display conference, “Polymer
stabilization and encapsulation in liquid crystal displays”, invited.
19. May 20, 2008, SID conference, Los Angles, Ca, “Achromatic Reduction of Off-axis Light Leakage
in LCDs by Compensated Phase Retardation Film,” poster.
20. June 5, 2008, Industrial Technology Research Institute, Hsingchu, Taiwan, “Cholesteric reflective
display,” 6 hours short course.
21. June 6, 2008, College of Electrical and Computer Engineering, National Chiao Tung University,
Taiwan, “Polymer network in liquid crystal and their applications,” invited.
22. June 9-10, 2008, National Cheng Kung University, “Cholesteric liquid crystal and polymer
stabilized cholesteric liquid crystal: optical properties and applications,” 8 hours short course.
23. June 12, 2008, Taiwan Display Conference, Taipei, Taiwan, “Flexible cholesteric reflective
display,” invited talk.
24. June 25, 2008, BOE Technology Group Co. LTD, Beijing, China, “Optically compensated bend
mode liquid crystal display,” invited.
25. June 27, 2008, Korea-Ukrainian-American joint symposium on New horizons of liquid crystal
science and applications II, Chonbuk National University, Korea,, “Polymer networks in liquid
crystals,” invited.
26. July 1, 2008, Jeju, Korean, International liquid crystal conference, “Chiral Propeller Liquid Crystal
Droplets: Structure and Response to Electric Fields,” Poster.
27. July 1, 2008, Jeju, Korean, International liquid crystal conference, “Effects of Pretilt Angle and
Random Noise on the Switching Dynamics of VA LCDs,” Poster.
28. August 5, 2008, Polytronix Inc, Dallas, “New Liquid displays,” Invited.
Sarah Hicks
Ph.D Candidate
Liquid Crystal Institute &
Chemical Physics Program
Kent State University
Kent, OH 44242-0001
(330) 990-6792
shicks@lci.kent.edu
Long Term Interests
Conduct research in liquid crystal/polymer composites and their use in display technology. Teaching
physics at a university and aiding undergraduate and graduate students in their research in liquid
crystals.
Current Research Projects
Detecting polarization freezing in nematic liquid crystal/polymer network systems. Polymer stabilized
vertical alignment mode displays.
Interest in short term projects for a company
I am interested in collaborating with a company by characterizing novel materials. I am open to on-site
as well as off-site internships.
Shawn Hurley
Ph.D Candidate
Liquid Crystal Institute &
Chemical Physics Program
Kent State University
Kent, OH 44242-0001
shurley@lci.kent.edu
Shawn is working for Dr. Yang on polymer stabilized liquid crystal displays and is in his 4th year of the
CPIP program.
His experience ranges the entire gamut from modeling, to fabrication, to
characterization. He is a member of SPIE, SID, Sigma Xi and IEEE.
Rafael Zola
Ph.D Candidate
Liquid Crystal Institute &
Chemical Physics Program
Kent State University
Kent, OH 44242-0001
rzola@lci.kent.edu
Long Term Interests
I’m interested in developing knowledge from basic liquid crystal science until the applied results by this
works. I’m interested in studying elastic properties as well as surface effects of liquid crystals. As my
field of experience is theory, in particular analytical calculation, I would like to try analytical results in
the laboratory, in particular if I could use computer simulations to improve my measured results. I also
have interest in using and learning more about applications of liquid crystals such as the areas where
polymer science is involved. Other fields of interest are adsorption-desorption of particles and memory
effect, anchoring effects in liquid crystals and mathematical problems for the liquid crystalline area.
Current Research Projects
At this moment, I’m working with defects in cholesteric liquid crystals and “natural” chiral dopant. For
the defects research, I’m interested in studying the propagation and the reasons for the formation of
defects, in particular the Oily Streaks defects. The thermal annealing process is one of my main focus,
due to the many variables involved and a possibility of surface effects due to this kind of treatment.
Further, I’m also interested in other methods for getting rid of these defects and I’m currently doing
some Monte Carlo simulation about these defects. For the “natural” chiral dopant, I’m studying chiral
molecules that can be used in the liquid crystal field, since they can reduce costs a lot once these new
dopant might cost even 1000 times less than the well known chiral dopants. Also, I am interested in the
main change made by these elements, such as response time, viscosity, etc., for cholesteric phases, TN’s
and STN’s.