Optically Controlled Alignment Of Liquid Crystals

1994 ◽  
Vol 345 ◽  
Author(s):  
Wayne M. Gibbons ◽  
Paul J. Shannon ◽  
Shao-Tang Sun

AbstractOptically controlled homogeneous-to-homogeneous alignment of liquid crystals using polarized light is reviewed. Application of this technology to liquid crystal display manufacturing is discussed. Important processing parameters such as tilt angle and optical energy density will be addressed.

2013 ◽  
Vol 2013 ◽  
pp. 1-11
Author(s):  
Y. J. Lee ◽  
T. S. Liu ◽  
Mao-Hsing Lin ◽  
Kun-Feng Huang

Liquid crystal display panels subjected to tactile force will show ripple propagation on screens. Tactile forces change tilt angles of liquid crystal molecules and alter optical transmission so as to generate ripple on screens. Based on the Ericksen-Leslie theory, this study investigates ripple propagation by dealing with tilt angles of liquid crystal molecules. Tactile force effects are taken into account to derive the molecule equation of motion for liquid crystals. Analytical results show that viscosity, tactile force, the thickness of cell gap, and Leslie viscosity coefficient lead to tilt angle variation. Tilt angle variations of PAA liquid crystal molecules are sensitive to tactile force magnitudes, while those of 5CB and MBBA with larger viscosity are not. Analytical derivation is validated by numerical results.


2006 ◽  
Vol 45 (No. 10) ◽  
pp. L282-L284 ◽  
Author(s):  
Yoshio Shimbo ◽  
Yoichi Takanishi ◽  
Ken Ishikawa ◽  
Ewa Gorecka ◽  
Damian Pociecha ◽  
...  

Crystals ◽  
2019 ◽  
Vol 9 (10) ◽  
pp. 543 ◽  
Author(s):  
Evgeny P. Pozhidaev ◽  
Timofey P. Tkachenko ◽  
Artemy V. Kuznetsov ◽  
Igor N. Kompanets

In-plane electro-optical switching (IPS) is a natural feature of a conventional planar-aligned display cell based on the deformed helix ferroelectric liquid crystal effect (DHFLC-effect) with a sub-wavelength helix pitch, if the tilt angle is close to 40 degrees.


Polymers ◽  
2019 ◽  
Vol 11 (6) ◽  
pp. 1051 ◽  
Author(s):  
Chuen-Lin Tien ◽  
Rong-Ji Lin ◽  
Chi-Chung Kang ◽  
Bing-Yau Huang ◽  
Chie-Tong Kuo ◽  
...  

This research applies the non-linear effect of azo dye-doped liquid crystal materials to develop a small, simple, and adjustable beam-splitting component with grating-like electrodes. Due to the dielectric anisotropy and optical birefringence of nematic liquid crystals, the director of the liquid crystal molecules can be reoriented by applying external electric fields, causing a periodic distribution of refractive indices and resulting in a diffraction phenomenon when a linearly polarized light is introduced. The study also discusses the difference in the refractive index (Δn), the concentration of azo dye, and the rising constant depending on the diffraction signals. The experimental results show that first-order diffraction efficiency can reach ~18% with 0.5 wt % azo dye (DR-1) doped in the nematic liquid crystals.


1998 ◽  
Vol 508 ◽  
Author(s):  
Yuri. A. Bobrov ◽  
Sean M. Casey ◽  
Leonid. Y. Ignatov ◽  
Pavel I. Lazarev ◽  
Daniel Phillips ◽  
...  

AbstractWe have developed new polarizing coating materials and processes which enable the fabrication of polarizers for large-area liquid-crystal displays. The polarizing materials are novel discotic surfactants which self-assemble in aqueous solutions to provide a stable liquid-crystalline phase within a wide range of concentrations and temperatures. These lyotropic liquid crystals in an aqueous medium can be spread on a substrate surface by a variety of techniques including a knife-like doctor blade, a rolling cylinder, or a roll-to-roll method. Under the shearing force applied during deposition, the liquid crystals align on the substrate forming a dichroic polarizer. This alignment process allows continuous production of large-area polarizing films at low cost compared with the current technology that requires stretching of the films. Thin coatings can be applied to flexible plastic films, glass, or rigid plastic substrates. Direct coating of the polarizing material on glass eliminates several process steps in liquid-crystal display production since lamination of the polarizing film is no longer required. These new polarizing films have a high optical performance including a polarizing efficiency of above 98% and a dichroic ratio as high as 7.7.


2020 ◽  
Vol 54 (1 (251)) ◽  
pp. 56-60
Author(s):  
H.H. Hovakimyan

In this work we study the propagation of light in a twist-oriented pleochroic nematic liquid crystal with pleochroic dye. The dependence of the intensity of transmitted light on the azimuthal angle of the linearly polarized incoming light has been investigated experimentally. As a result, the role of absorption anisotropy has been identified.


2005 ◽  
Vol 13 (21) ◽  
pp. 8349 ◽  
Author(s):  
Xingpeng Yang ◽  
Yingbai Yan ◽  
Guofan Jin

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