Patterned Photoalignment in Thin Films: Physics and Applications

Crystals

Aleksey Kudreyko¹  Qi Guo²  Vladimir Chigrinov³ 

[1] Department of Medical Physics and Informatics, Bashkir State Medical University, 450008 Ufa, Russia;School of Instrumentation and Optoelectronic Engineering, Beihang University, Beijing 100191, China;School of Physics and Optoelectronic Engineering, Foshan University, Foshan 528325, Guangdong, China;

关键词: photoalignment of liquid crystals;    electro-optic modes;    new devices;    imaging technologies;    displays;    photonics;   

DOI  :  10.3390/cryst11020084

来源: DOAJ

【 摘 要 】

Photoalignment of liquid crystals by using azo dye molecules is a commonly proposed alternative to traditional rubbing alignment methods. Photoalignment mechanism can be well described in terms of rotational diffusion of azo dye molecules exposed by ultraviolet polarized light. A specific feature of the irradiated light is the intensity dependent change of azimuthal anchoring of liquid crystals. While there are various mechanisms of azo dye photoalignment, photo-reorientation occurs when dye molecules orient themselves perpendicular to the polarization of incident light. In this review, we describe both recent achievements in applications of photoaligned liquid crystal cells and its simulation. A variety of display and photonic devices with azo dye aligned nematic and ferroelectric liquid crystals are presented: q-plates, optically rewritable flexible e-paper (monochromatic and color), and Dammann gratings. Some theoretical aspects of the alignment process and display simulation are also considered.

【 授权许可】

Unknown