高分子配向研製高傾角雙穩態液晶顯示元件及光電特性之研究

Study on Bistable Liquid Crystal Displays of High Pretilt Angles Stabilized by Polymer

謝依珊(Yi-San 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(2011年)

摘要

本研究將光可聚合的高分子材料，以不同比例混入雙頻液晶，控制其照光時間製作出不同預傾角的液晶元件樣品。
　　同向配向的空液晶盒，灌入摻雜旋光性物質的雙頻液晶，其d/p值約為1.17，經由UV光照射使高分子調控液晶預傾角，利用雙頻液晶的特性以交流電壓驅動，使其能夠在Twist Bend及2π Twist排列的兩個穩態間做轉換，達到雙穩態的目的。此雙穩態元件在穩定態時不需消耗功率，具有節能省電的優點。
　　在本論文中，針對不同高分子比例及預傾角改變所產生的雙穩態現象及光電特性，透過實驗及模擬做出探討。另外，也對改變預傾角所造成的單穩態及膽固醇相做分析，使在製作此元件時出現的現象更加了解。

關鍵字

雙穩態 ； 雙頻液晶 ； 高分子

並列摘要

In this study, we mix polymer materials, which can be polymerized by UV light, with dual-frequency nematic liquid crystal (LC) in different proportions. By controlling the UV exposure time, we can fabricate liquid crystal cells with different pretilt angles.
　　The liquid crystal cell with parallel rubbing is doped with chiral material, the d/p ratio ≈ 1.17. After exposed to the UV light under applied electric field, the pretilt angle of LC becomes high. We can switch the LC cell between twist-bend and twist-nematic states by AC voltage with different frequency, to achieve the purpose of bistability. This bistable cell doesn’t require power when it is in stable states, and has the advantage of energy saving.
　　In this study, we discuss the electro-optical characteristics of bistable switching with different proportions and different pretilt angle by experiment and simulation. The properties of monostable and cholesteric states are also being discussed.

並列關鍵字

Bistable ； Dual-Frequency LC ； Polymer

參考文獻

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