臺灣博碩士論文加值系統

本篇論文主要是以垂直配向模態之單間隙半穿透半反射液晶顯示器之設計模擬為主，由於光線穿過穿透式（T part）液晶層一次而外部光源則穿過反射式（R part）液晶層兩次，因此我們分別設計不同的電極以期穿透與反射的光電曲線（T-V and R-V curves）能夠重合。我們設計的結構希望可以在穿透部分產生較強的電場，而反射部分則是較弱電場，這樣就可以在單一驅動電路（single TFT-driving circuit）下使穿透與反射液晶層達到相同的光延遲效果，換句話說則是得到相同的穿透量（transmittance）與反射量（reflectance）。我們知道垂直配向模態先天上的視角表現是較差的，所以我們還利用了補償膜（compensation film）與多域結構（multi-domain）來嘗試使我們設計的結構達到更廣視角的要求。
本篇論文主要分成兩個部分，一是以垂直配向模態（VA mode）為主搭配部分分佈電極的結構，稱為Partial Switching；而另一則是以邊緣電場效應模態（Fringe Field Switching mode）為主並利用垂直配向為初始模態的結構，稱為VA-FFS

This research in this thesis is based on the use of Vertically Aligned (VA) liquid crystal mode in the design and development of single-cell-gap Transflective TFT-LCDs. In particular, we focus on using different electrode designs between T and R part in order to match the corresponding T-V and R-V curves. Since the light passes through the liquid crystal layer twice in the R part but only once in the T part, the structure we design is required to produce stronger electric fields in T part and weaker electric fields in the R part so that similar retardation change in T and R can be obtained. As a result, the transmittance and reflectance can become very similar even when the pixel is driven by a single TFT-driving circuit. Apart from matching the T-V and R-V curves, we also try to use compensation film and multi-domain approaches to simulate and improve the narrow viewing angle property of the VA liquid crystal mode.
This thesis is divided into two parts; the first one is based on a Partial-Switching scheme which employs a partial distributed electrode design while the second one is based on the use of a VA-FFS liquid crystal mode which has a VA liquid crystal mode for the original OFF state and FFS mode for the driven ON state.

致謝 I
摘要 II
Abstract III
目錄 IV
圖目錄 VII
表目錄 XI
第一章 緒論 1
1.1 研究背景與簡介 1
1.2 穿透式液晶顯示器簡介 1
1.3 反射式液晶顯示器簡介 2
1.4 半穿透半反射液晶顯示器簡介 2
1.4.1 Double Cell Gap TR-LCD 2
1.4.2 Single Cell Gap TR-LCD 3
1.5 模擬軟體簡介 4
1.5.1 2DIMMOS… 4
1.5.2 DIMOS… 5
1.6 名詞與定義 6
1.7 垂直配向液晶模態簡介 6
第二章 Partial Switching Single Cell Gap TR-LCD 7
2.1 Partial Switching結構與原理 7
2.1.1 穿透式光行進與極化狀態 9
2.1.2 反射式光行進與極化狀態 11
2.2 電極分佈的產生的相對電場 13
2.2.1 T-part所產生電場 13
2.2.2 R-part所產生電場 13
2.3 各種參數原理與效應 14
2.3.1 預傾角（pre-tilt angle） 14
2.3.2 液晶層厚度（cell gap：D） 15
2.3.3 反射部分電極分佈 16
2.3.4 不同的雙折射（△n） 18
2.4 最佳的TR matching 19
2.4.1 低預傾角模擬結果 23
2.4.2 針對cell gap的改善 24
2.4.3 針對預傾角角度改善 26
2.4.4 電極寬度改善 36
2.4.5 88°預傾角下液晶層厚度改善 37
2.5 改變電極以得到最佳重合曲線 41
2.5.1 protrusion＋斜向電極 41
2.5.2 zigzag 結構 46
2.6 灰階反應速度及討論 49
2.6.1 穿透部分灰階反應速度討論 50
2.6.2 反射部分灰階反應速度討論 52
2.6.2.1 普通反射式電極 52
2.6.2.2 斜向電極反射式電極 53
2.7 視角及補償 54
2.7.1 穿透部分視角與補償 54
2.7.1.1 利用-c plate補償暗態 56
2.7.1.2 利用a plate +o plate補償灰階穩定度 60
2.7.1.3 4-domain結構 63
2.7.2 反射部分視角與補償 64
2.7.2.1 利用-c plate補償暗態 65
2.7.2.2 利用biaxial film補償 67
2.8 總結 70
第三章 VA-FFS Single Cell Gap TR-LCD 72
3.1 VA-FFS結構與原理 72
3.1.1 FFS結構介紹 72
3.1.2 半穿透半反射結構 73
3.1.3 避免使用in-cell retarder 74
3.1.4 光源極化狀態討論 75
3.2 液晶旋轉角度（rubbing angle）原理與影響 78
3.3 液晶預傾角度（pre-tilt angle）原理與影響 80
3.4 電極分佈的產生的相對電場效應 82
3.4.1 電極寬度(P)效應 82
3.4.2 電極間距（G）效應 84
3.4.3 介電層厚度（dielectric layer thickness）效應 86
3.4.4 液晶層（cell gap）厚度效應 87
3.5 最佳的TR matching 89
3.5.1 低預傾角模擬結果 89
3.5.2 較高的預傾角避免暗態漏光 91
3.5.3 同預傾角與同電極寬度的模擬 92
3.6 灰階反應速度及討論 95
3.6.1 穿透部分灰階反應速度討論 96
3.6.2 反射部分灰階反應速度討論 98
3.7 章節總結 100
第四章 結論 101
參考資料 103

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