棱镜晶体旋转法测量液晶器件大预倾角

晶体旋转法是测量液晶分子预倾角的常用方法,但不适用于测量20°~70°之间的预倾角。提出一种棱镜辅助晶体旋转法测量预倾角的方案。把液晶盒夹在两个直角棱镜间,入射光从前面棱镜一个面入射,经过液晶盒从后面棱镜出射,改变入射光的入射角,测量出射光透过率,能得到对应双折射相位差为零、透射光强最大的入射角,进而由几何光学关系确定预倾角。数值模拟和实验结果显示该方法具有可行性。

Prism Assisting Crystal Rotation Method to Measure High Pretilt Angle of LCD

The crystal rotation method is usually used to measure the pretilt angle of liquid crystal molecules, but it is unsuitable to measure the pretilt angle of 20°～70°. In order to expand the range of applicability of crystal rotation method, we propose the pretilt angle measurement method to use prisms to assist the crystal rotation. A liquid crystal cell is located between two prisms, and the incident light enters from the former prism, passes through the crystal cell and exits from the back prism. We will get the incident angle on condition that the birefringence retardation is zero and the light transmission is maximal, and obtain the pretilt angle with optical geometry. The numerical simulation and experimental results show a feasibility of this method.