- 學位論文
摻雜高分子的雙頻液晶應用在OCB Cell之光電特性研究
Electro-Optical Characteristic of Dual-Frequency Liquid Crystal in OCB Cell with Polymer Aligned Material
摘要
為追求良好的影像品質，需要一個具備廣視角且具有快速響應的顯示模式，因此光學補償彎曲模式的顯示元件在研究上特別受到重視。但由於OCB在Bend state操作前須由Splay state跨過極大的自由能障方能轉態形成Bend state，導致需要較大的轉態電壓及較長的暖機時間，因此降低它的實用性。 為解決OCB模式中轉態電壓及暖機時間等問題，我們在OCB cell內加入兩款光聚合單體，照光並同時施以適當的照光電壓，形成高分子網束縛液晶分子在較高的傾角，使初始狀態維持在高傾角Splay或Twist排列，能有效降低或解決轉態電壓的問題。 而近年來節能省電的觀念興起，在顯示器上希望能達到雙穩或多穩的狀態，因此我們液晶材料上選用雙頻液晶，藉由雙頻液晶的雙頻驅動特性做出達到雙穩態液晶顯示模式的液晶盒。 本論文針對雙頻液晶與照光單體的結合運用，在不同單體濃度與照光電壓下，對OCB Cell模態的影響做光電特性的研究與探討。
並列摘要
Optically compensated bend (OCB) mode liquid crystal display (LCD) intrinsically has features of fast response time and wide viewing angle that is suitable for showing high image quality and fast moving picture without blurring. When the conventional OCB cell is driven from initial splay state to operating bend state the need of high transferred energy leads to a long warm up time and high voltage. In order to solve these problems, the OCB cell having high pretilt splay or twist state is developed by using polymer stabilization method (PS). In this experiment, two kinds of curable monomer are mixed together with liquid crystal material and an ac electric field is applied during photo-polymerization process. Recently, bistable LCD has attracted much attention from the concept of low power consumption because the image can be stable without applied voltage and frames do not refresh frequently. In this study, a bistable OCB cell which used dual frequency liquid crystal material is investigated. The electro-optical characteristics of the bistable OCB cells with different mixture concentration and curing voltage is studied.