反射式液晶显示器的导波研究

摘要

The 90° reflective-mode MTN (mixed twist nematic) liquid crystal cell ,which is used for liquid crystal on silicon (LCOS) display ,is studied by using the improved fully leaky optical guided wave technique . The marked characteristic of the experimental liquid crystal cell is that the transparent electrode ITO (indium-tin-oxide) on one of substrates was replaced by aluminum coating ,so that there are only four sets of reflective signals :Rpp ,Rss ,Rps ,Rsp .From the results of experiment ,it is found that there are differences between the polarization-conversion signals Rpsand Rsp ,which indicates that the director has small tilt angle on the upper and lower substrates .Then the experiment data were fitted to the modeling predictions from the program based on the liquid crystal continuum theory and multilayer optical theory ,and finally the related information of different layers of the cell (alignment layer ,ITO ,aluminum coating ) is obtained ,including the optical permittivity and the corresponding thickness of each layer .%利用改进的全漏光导波技术对硅基液晶（LCOS ）显示用的反射式90°M T N液晶盒进行研究。液晶盒的一个基板上的透明电极IT O被铝膜代替，故测得实验数据中只有4组反射信号：Rpp 、Rss 、Rps 、Rsp 。从实验结果发现，偏振转换信号 Rps和 Rsp之间存在差异，说明液晶的指向矢在上下基板具有小的预倾角。使用基于液晶连续体理论和多层介质光学的模拟程序，对得到的实验数据进行拟合，最终得到液晶盒各层（取向层、ITO、铝膜）的相关信息，包括每层的光学介电常数及厚度。