液晶顯示器件因配向方法的不同，常見的有扭轉向列型(TN) 型、超扭轉向列型(STN)型及多重區域垂直配向(MVA)型等液晶顯示器。由於這些配向方法的不同，所以對液晶分子預傾角的要求也有所不同。現行液晶分子預傾角選擇的方式有(1)選擇不同 polyimide 材料，經特定摩擦強度，而產生特定之預傾角(2)採用低預傾角 polyimide 材料，依不同比例混合高預傾角 polyimide 材料，而達到預傾角之調變。

而在本研究中提出一種雙層結構高分子配向層(double alignment layers)，以垂直配向層(homotropic layers)作為底層，水平配向層(homogenous layers)作為上層，藉由改變該水平配向膜之厚度來改變配向膜之表面自由能(surface free energy)，同樣可以達成調變液晶分子預傾角的效果。並且可以補償液晶顯示器件因摩擦配向不足，而發生暗態漏光的問題，具有較高的對比度。

在由於本實驗在液晶分子較高預傾角(pretilt angle)範圍調變效果較佳，且面板各區域液晶分子預傾角均勻度較高，所以可以有效應用在各式垂直配向(homotropic)液晶顯示器件上，例如: MVA，VA-STN，DSTN。

The liquid-crystal display because matches to the method is different , common has the TN monitor , the STN monitor , and the MVA monitor . Because these match to the method difference , therefore liquid crystal molecule pretilt angle is also different . Present liquid crystal molecule pretilt angle choice way includes : (1) Chooses the different polyimide material , after specific rubded intensity , but produces specific pretilt angle. (2) Uses low pretilt angle the polyimide material , mixes high pretilt angle according to the different proportion the polyimide material , but achieved accent of the pretilt angle changes .

But in this research proposed double alignment layers , takes the first floor by homotropic layers , uses homogenous layers does for the upper formation , the surface free energy of the alignment layer can be easily controlled by adjusting the thickness of the top polyimide layer, similarly may achieve the accent to change liquid crystal molecule pretilt angle the effect . And may compensate the liquid crystal display to be insufficient because of rubbed polyimide , but has the question which dark condition is exposed , has a higher contrast gradient .

Because this experiment scope accent changes the effect in liquid crystal molecule higher pretilt angle good , also kneading board various regions liquid crystal molecule pretilt the angle uniformity is higher , therefore may effectively apply on various types homotropic liquid crystal display component , for example: MVA , VA-STN , DSTN liquid-crystal display .

第一章 緒論..…………………………………………1
第二章 實驗之理論基礎和原理…..…………………2
2-1 液晶簡介……………………………………..2
2-1-1 液晶種類……………………………………..2
2-1-2 液晶的光學性質……………………………..4
2-2 液晶分子排列之方法..………………………11
2-2-1 基板面直接配向處理法……………………..11
2-2-2 基板面間接配向處理法……………………..12
2-2-3 基板面變形處理法…………………………..13
2-3 液晶分子在固體表面上行為..………………15
2-3-1 接觸角與表面自由能..………………………15
2-4 配向膜基本功用……………………………..22
2-5 摩擦強度..……….……………………….......24
2-6 預傾角及其在顯示器中的重要性…………..25
2-7 調變預傾角的方法….……………………….26
2-7-1 斜向蒸鍍………………...…………………..26
2-7-2 光配向方式…….………...…………………..28
2-7-3 PI混合方式…….…………….......…………..30
2-7-4 Silane混合方式(OTS/MAP). ………………33
2-7-5 Silane混合方式(DMOAP/MAP).…………...35
2-7-6 研究動機...………......………………………36
第三章 實驗儀器與實驗步驟..…..………………….39
3-1 製備雙層配向液晶盒之流程……………….39
3-1-1 雙層配向基板製作程序..…………………...40
3-1-2 液晶CELL封裝與灌注..……………………46
3-2 雙層結構配向層表面分析………………….50
3-2-1 膜厚量測儀…..……………………………...50
3-2-2 接觸角量測儀…..…………………………...52
3-2-3 預傾角量測………………………………….54
3-3 雙層結構配向層光電特性分析…………….57
3-3-2 光電量測系統…….…………………………57
3-3-2 光的反應時間量測….………………………58
第四章 實驗結果與討論分析
4-1 塗佈配向膜之轉速對成膜均勻度之影響.....60
4-1-1 垂直配向材料（底層）之塗佈結果….……60
4-1-2 水平配向材料（上層）之塗佈結果…….....61
4-1-3 雙層配向材料（底層 + 上層）之塗佈結果.62
4-2 討論異質雙層配向結構之表面自由能…….63
4-2-1 表面自由能對異質雙層配向結構之影響….63
4-2-2 表面自由能對液晶分子的預傾角之影響….66
4-3 分析雙層配向結構液晶盒之光電特性.……67
4-3-1 上層水平配向層厚度對光的反應時間之影.67
4-3-2 底層垂直配向層對暗態漏光之改善……….69
第五章 結論與未來工作…………………………….73
參考文獻……...…………………………………………...75
附錄...………………………………………………………80

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