高分子材料控制OCB液晶盒的預傾角及光電特性研究

Electro-Optical Characteristics of a OCB Liquid Crystal Display with Polymer Controlled Pretilt Angle

駱建樺(Jian-Hua Luo)

指導教授 ： 陳殿榮

國立臺北科技大學/電資學院/光電工程系研究所/碩士(2010年)

摘要

本文研究高分子調變液晶配向之預傾角。首先使用三種高分子單體，分別為單體A，單體C及單體A混合單體C，摻雜入液晶E7形成混合物，將混合物注入至Homogeneous-cell內，外加固化電壓Vuv=10V時，照射UV光60分鐘，使高分子聚合，藉由光穿透率量測、響應時間量測、接觸角量測及SEM量測，探討高分子單體對液晶排列的效應。
其次利用單體A混合單體C與液晶的混合物注入πcell，在照射UV光同時外加不同電壓，使配向膜表面形成高分子網(Polymer network)的結構。在無施加電壓下，液晶初始穩定在splay、twist或bend排列，以偏光顯微鏡圖、穿透率量測及視角量測進行光電特性分析，且利用Dimos軟體模擬π-cell初始狀態的預傾角。

關鍵字

π-cell ； 預傾角 ； 單體 ； 高分子

並列摘要

In this study, we used photo-polymer to control the pretilt angle in a LCD cell. First, we added monomer A, monomer C, and a mixture of monomers A and C to liquid crystal E7, respectively. The mixture of monomers and liquid crystal was filled into a homogeneous cell. The photo-polymerization proceeded in the homogeneous cell with an ac electric field applied to it. We varied the UV exposure time and investigated the electro-optical effect on LC cell.
Secondly, liquid crystal E7 doped with monomers A and C was filled into a π-cell. The LC molecular alignment and electro-optical characteristics in the cells were investigated by polarizing optical microscopy, voltage dependent transmission and viewing angle. We verified the experimental result by simulated analysis.

並列關鍵字

π-cell ； pretilt angle ； monomer ； polymer

參考文獻

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