參雜二氧化矽奈米粒子之液晶元件特性研究及應用

Abstract

本論文在混合排列向列型液晶盒中摻雜二氧化矽奈米粒子，藉由施加脈衝電壓使奈米粒子產生泳動，在脈衝電壓下,粒子累積於水平配向端，進而改變液晶元件為垂直排列方式，即使關掉電壓，液晶仍穩定垂直排列，故液晶盒具有雙穩態效果。而由此元件具雙穩態特性進而分析影響雙穩態效應的成因，論文中分別以不同實驗變因(如:液晶種類、配向膜種類、配向膜厚度、摻雜奈米粒子濃度和奈米粒子種類等)，來探討各參數對元件之雙穩態特性有何影響，其實驗結果顯示這些參數的改變，的確會造成穩態效果的差異。除此之外，論文中也將此類元件應用於具雙穩態賓主型液晶元件上，除了不需偏振片賓主型元件的顯示特性可增加光的使用效率，避免不必要能源浪費，雙穩態的顯示特性更可進一步達到節能的目的。

With doping silica nanoparticles in a hybrid aligned nematic (HAN) liquid crystal device (LCD), the electrophoretic effect of nanoparticles was observed by applying a pulse voltage. Under a pulse voltage excitation, the silica nanoparticles accumulated on the homogeneous alignment (HA) layer, and it changed the alignment property near the HA layer. The stabilization of silica nanoparticles on the HA layer provided a stable vertically aligned LC cell even switching off the voltage. This work studied the influences of liquid crystal, alignment material, thickness of alignment layer, nanoparticles and concentration of nanoparticles on the bistability of HAN LCDs. In addition, the technique of achieving bistable HAN LCDs was applied on a bistable Guest-Host (G-H) LCD. The characteristic of bistable G-H LCD was studied in this work.