具粗糙反射面相變賓主型液晶顯示器特性之探討

Abstract

本文主要是對“反射式相變賓主型液晶顯示器”，分兩部份來研究： 第一部份是研究在固定液晶盒厚度下，不同的液晶配方和相變的臨界電場的關係以及和液晶層相接觸的垂直配向膜，在傳統不作磨擦配向與不同摩擦配向的情況下，對其液晶顯示器光電特性，如臨界電壓及應答速度的影響。 第二部份是設計具有廣視角的粗糙反射板。在此部份將介紹散射理論及粗糙反射板之設計原則。利用散射理論，發展出計算一維及二維粗糙表面散射強度分佈的程式。這部份最終的目的是利用隨機分佈的微小凹凸顆粒來設計粗糙反射板，藉著計算及分析其散射特性，調整微小凹凸顆粒的形狀與分佈，求得最佳化的粗糙反射板的設計。

Two important properties of "Reflective Phase-Change-Guest-Host (PCGH) Mode Liquid Crystal Display (LCD)" are studied, one is liquid crystal and the other one is its reflector. First, the threshold electric fields and response time of the liquid crystal for PCGH mode with different ratio of cell gap and pitch (d/p0) by using the same cell gap but changing the concentration of chiral dopant is studied. In experiment, the samples with rubbing homotropic aligned PI by different method can reduced the response time of traditional PCGH mode LCD. Second, the method of optimum design the rough reflector with bumps is investigated. The randomness (R) of the bumps' positions on reflector is designed between 0.4 to 0.6 to reduced the interference, and roughness factor (K) of bumps' shape is designed between 6 to 10 to get brighter and wider viewing angle by simulation and experiments.