高分子材料研製雙穩態液晶顯示元件及光電特性研究

Study on the electro-optical properties of bistable liquid crystal display with polymer network

謝欣容(Hsin-Jung Hsieh)

指導教授 ： 陳殿榮 ； 吳俊傑

國立臺北科技大學/電資學院/光電工程系研究所/碩士(2013年)

摘要

本研究製作出兩種類型之OCB雙穩態液晶顯示元件並研究其光電特性。利用光可聚合的高分子單體材料，以固定比例混入雙頻液晶，控制UV光的曝光時間提升預傾角，製作出初始態分別為twist state和bend state兩種液晶顯示元件，再利用雙頻液晶在不同頻率下介電異向性會改變的特性，使前者能在left-hand twist及right-hand twist排列的兩個穩態之間做轉換，而後者能在bend及spaly排列的兩個穩態之間做轉換，達到雙穩態的特性。
本研究主要可分為兩個部分，第一部分為left-hand twist(LT) state和right-hand twist(RT) state的雙穩態元件，並討論此種雙穩態在不同電壓下驅動的特性；第二部分為bend state 和splay state的雙穩態元件，同樣也討論此種雙穩態在不同電壓下驅動的特性，並與第一部分的雙穩態元件做比較。

關鍵字

雙穩態 ； 雙頻液晶 ； 高分子

並列摘要

In this study, we propose two kinds of bistable liquid crystal (LC) displays and study their electro-optical properties. We mix the monomer, which can be polymerized by UV light, with the dual-frequency liquid crystal in a fixed proportion, and control the UV exposure time of the mixture to increase the liquid crystal pretilt angle. We fabricate two kinds of liquid crystal cells which are initial twist state and initial bend state. Because the dual-frequency liquid crystal with different dielectric anisotropy at different frequencies, the former LC cell can switch between left-hand twist and right-hand twist states while the latter LC cell can switch between bend and spaly states to achieve the bistability.
This study can be divided into two parts. First, we discuss the electro-optical characteristics of the bistable LC cell which has two stable states of left-hand twist (LT) and right-hand twist (RT) states. Next, we also discuss the electro-optical characteristics of the bistable LC cell which has two stable states of bend and splay states.

並列關鍵字

Bistable ； Dual-Frequency Liquid Crystal ； Polymer

參考文獻

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