本論文之研究目的是以實驗方式尋求達成液晶配向之預傾角調變可行方法。實驗方法以選擇兩種矽烷(silane)材料依不同比例混合進行液晶配向，兩種矽烷分別是垂直配向用的DMOAP(N,N-dimethyl-N-octadecyl-3
-aminopropyltrimethoxysilyl chloride)，以及水平配向用的MAP(N-methyl-3
-aminopropyltrimethoxysilane)。
液晶配向採用不同比例濃度之矽烷溶液浸泡方式，並形成液晶配向膜於玻璃基板上，對於不同配向條件之液晶樣品進行觀察並測量其預傾角；混合後之矽烷溶液放置時間對液晶配向產生之影響也是實驗觀察的重點。我們使用偏光顯微鏡觀察液晶樣品配向的結果，並架設晶體旋轉法裝置測量液晶樣品的預傾角。
實驗結果顯示利用不同比例濃度之矽烷溶液浸泡方式確實可以達到調變液晶預傾角約在十幾度的範圍，矽烷溶液之放置時間也影響液晶預傾角之變化。

In this thesis, we study a suitable method possessing a capability of adjusting pretilt angle for liquid crystal alignment. In our experimental, two kinds of silane are used to blend with various concentration ratio for liquid crystal alignment, which are DMOAP (N,N-dimethyl-N-octadecyl-3-
aminopropyltrimethoxysilyl chloride) for homeotropic alignment and MAP
(N-methyl-3-aminopropyltrimethoxysilane) for homogeneous alignment, respectively.

In order to align liquid crystals in cells, the composed glass substrates are dipped in blended silane solution to form the alignment thin film on glass surfaces before cell assembly. Pretilt angles are observed and measured in different blended silane conditions. The qualities of liquid crystal alignment in cells are observed with the polarized optical microscope (POM), and pretilt angles are measured with a setup based on the crystal rotation method.

Experimental results show that adjustable pretilt angle about 16~19 degrees are achieved except homeotropic and homogeneous alignment in conditions of various blended silane solution. Meanwhile, we also find that the time after the fresh blended silane solution is an effective factor for pretilt angle variation.

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