Anchoring Properties of Homogeneously Aligned Nematic Liquid Crystal Cells

• Main Authors: Yen-Ting Chen, 陳彥廷
• Other Authors: Shu-Hsia Chen
• Format: Others
• Language: zh-TW
• Published: 2001
• Online Access: http://ndltd.ncl.edu.tw/handle/31337175013610440962

碩士 === 國立交通大學 === 光電工程所 === 89 === The photo-induced anisotropy on a photo-aligning film can be controlled by varying the exposure time of linearly polarized UV light. Utilizing this property, we prepared the homogenously aligned nematic liquid crystal(LC) cells with different anchoring strength. Nonzero pretilt angle can be achieved with obliquely incident UV light. The resulting anchoring properties were studied by measuring the pretilt angle, cell gap and anchoring energy of LC cells. By measuring the phase retardation of the liquid crystal cell versus the applied voltage, the polar anchoring energy homogenously aligned cell was found to be 1×10-3 J/m2 in our experiment. The alignment instability in LC cells caused by heating or exposure to strong visible laser beam was also investigated to ensure the long term applicability of the photo-aligning film.