臺灣博碩士論文加值系統

在科技爆發性進步的時代裡，液晶在人類生活上的應用廣泛度可見一斑，不論是在電視、手機、手錶、電腦及大型動態看板等用途都看得見其蹤跡，甚至可利用液晶特性以電壓驅動的方法來調整窗戶透光度，在三維顯示技術科技上也有顯著的突破，而最明顯的改變就是顯示技術，液晶電視的發明取代了陰極射線管電視，使得過去幾十年間大家投入大量心力去改進液晶顯示技術。
顯示器技術的改進有兩個大方向，其中一項是藍相液晶材料的開發，另一項是顯示器內部結構的改變，在材料方面，近年來發現的穩定型高分子藍相液晶已經算液晶研究裡大家耳熟能詳的材料，不同於一般液晶的是藍相液晶在電場中主要是遵守克爾效應，以改變其分子形狀的方式產生雙折射的效果。藍相液晶還未能在生活中有所應用，主要原因是藍相液晶需要更高的電壓來驅動才有好的穿透率表現，因此針對過高的驅動電壓，我們採用改變電極結構來達到降低電壓和提高穿透率，模擬電壓與穿透率的關係，進一步分析改善的可行性，以達到節省製程上重複實驗所耗費的成本與時間。
本論文主要以Techwiz模擬軟體設計三階電極結構的設計對高分子穩定型藍相液晶(PSBPLC)材料進行穿透率的模擬，藉由控制電極間距G(electrode gap)、電極寬度W(electrode width)、液晶盒厚D(cell gap)等參數來模擬藍相液晶的表現，以及分析結構配合各參數是否能提高穿透率和降低驅動電壓，文中會分別對三階電極在二維(Two-Dimension)及三維(Three-Dimension)結構模擬的結果進行分析，並且比較三階電極在二維結構與三維結構上的改善。

In the era of explosive technology growth, the application of liquid crystals in human life has been widely seen . The use of liquid crystal can be found in television , mobile phones , watches , computers and large-scale dynamic billboards and so on. The liquid crystal properties can also be used as electro-optic switch to adjust the window transmittance. It has also made a great progress in the technology of three-dimensional (3D) display in recent years. The most important application of liquid crystal so far has been in display technology. The invention of the LCD television replaces the cathode ray tube television, it has made us put a lot of efforts to improve technology of liquid crystal displays in recent decades.

Improvement in display technology can involve different aspects. One of them is to develop new liquid crystal technologies, such as Blue Phase liquid crystal technology with fast response time. Polymer stabilized blue-phase liquid crystals (PS-BPLC) have been developed in recent years. Different from other liquid crystals, the electro-optic effects of blue-phase liquid crystal mainly follows the Kerr effect, i.e. field-induced refractive index change of blue phase liquid crystals in order to induce the character of birefringence. The application of blue-phase liquid crystal has not been used in commercial products yet. The main reason is that the blue-phase liquid crystal needs to be driven by much higher operating voltage in order to have a high transmission. By changing electrode structure we can lower the operation voltage and improve the transmission. By simulating the relationship between voltage and transmission, we can analyze the feasibility of improvements of the new structure, in order to save the cost and time spent on fabrication experiments.

In this thesis, we use commercial 3D LCD software “Techwiz” to simulate the transmittance of PS-BPLC material by designing three level electrode structure . By controlling the parameters of electrode gap(G) , electrode width(W) , cell gap(D), we can calculate the performance of blue-phase liquid crystal, to analysis whether these parameters can promote higher transmittance and lower operating voltage or not. In the content of this thesis, we will analyze the simulated results of two-dimension (2D) and three-dimension (3D) structure, and also compare the improvements of three level structure applied in 2D and 3D structures.

目錄
口試委員會審定書 ............................................#
誌謝 ..................................................... ii
中文摘要 ..................................................iii
ABSTRACT ...................................................V
Chapter 1 液晶與顯示器簡介................................1
1.1 顯示器類型介紹.......................................1
1.1.1 穿透式液晶顯示器(Transmissive LCDs)..................1
1.1.2 反射式液晶顯示器(Reflective LCDs)....................2
1.1.3 半穿透半反射式液晶顯示器(Transflective LCDs)..........3
1.2 液晶顯示器結構分類....................................5
1.2.1 扭轉向列型液晶顯示器(Twist Nematic LCDs，TN–LCDs).....5
1.2.2 超扭轉向列型液晶顯示器(Super Twist Nematic LCDs，STN–LCDs) ....................................................6
1.2.3 薄膜電晶體液晶顯示器(Thin Film Transistor LCDs，TFT–LCDs) ....................................................7
1.2.4 垂直配向液晶顯示器(Vertical Alignment LCDs，VA LCDs) ............................................................7
1.2.5 平面轉換(橫向場效應)液晶顯示器(In-Plane-Switching LCDs，IPS LCDs)...................................................8
1.2.6 邊界電場切換液晶顯示器(Fringe-Field-Switching LCDs，FFS LCDs) ....................................................9
1.3 液晶簡介............................................10
1.4 液晶的種類..........................................11
1.4.1 向列型(Nematic)液晶.................................11
1.4.2 層列型或距列型(Smetic)液晶...........................12
1.4.3 膽固醇型(Cholesteric)液晶...........................13
1.4.4 圓盤形(Disotic)液晶.................................14
1.5 液晶物理 ...........................................15
1.5.1 液晶特性 ...........................................15
1.5.2 液晶光學的異向性(anisotropic).......................16
1.5.3 液晶介電的異向性(dielectric anisotropic)............18
1.5.4 液晶連續彈性理論(elastic continuum theory)..........19
Chapter 2 藍相液晶介紹................................20
2.1 藍相液晶(Blue Phase Liquid Crystal , BPLC)..........20
2.1.1 藍相液晶的發現......................................21
2.1.2 藍相液晶特性........................................21
2.2 高分子穩定型藍相液晶(Polymer–Stabilized Blue Phase Liquid Crystal)............................................22
2.2.1 克爾效應(Kerr effect)...............................23
2.2.2 藍相液晶旋光性......................................25
2.2.3 藍相液晶的布拉格繞射雙螺旋柱結構......................26
Chapter 3 Techwiz模擬軟體介紹.........................28
3 Techwiz功能介紹.....................................28
3.1 Techwiz主程式參數設定...............................33
3.1.1 三維三階電極結構(Three Dimension Three Level Electrode Structure).................................................37
3.2 文獻探討............................................39
3.2.1 三階電極應用於平面轉換顯示器(Three Level In-Plane-Switching).................................................39
3.2.2 Electro-optics of polymer-stabilized blue phase liquid crystal displays....................................41
3.2.3 Modeling of Blue Phase Liquid Crystal Displays.....43
3.3 研究動機............................................45
Chapter 4 研究模擬結果與討論...........................46
4.1 三階電極平面轉換電場應用於藍相液晶....................46
4.1.1 三階平面轉換電極結構與液晶轉向電場分布圖..............46
4.1.2 電極寬度(Electrode Width)與電極間距(Electrode Gap)之穿透率對電壓關係圖(V-T curve).................................48
4.1.3 Conventional IPS versus Three Level IPS............51
4.1.4 Conventional IPS versus Three Level IPS with Blue Phase Liquid Crystal.......................................53
4.2 三維電極結構(Three Dimension Electrode Structure)應用於藍相液晶....................................................55
4.2.1 三維邊界電場切換(Three Dimension Fringe Field Switching , 3D-FFS)應用於藍相液晶...........................56
4.2.2 鏤空型三維邊界電場切換(Three Dimension Fringe Field Switching , 3D-FFS)應用於藍相液晶...........................63
4.3 鏤空型三維三階邊界切換電極結構(3D Three Level FFS)應用於藍相液晶 ...................................................70
4.3.1 鏤空型三維三階邊界切換pixel1電極邊長對T-V curve關係...73
4.3.2 鏤空型三維三階邊界切換pixel電極厚度對V-T curve關係....75
4.3.3 鏤空型三維三階邊界切換電極鏤空圓半徑(Hole Radius)對V-T curve關係..................................................78
4.3.4 鏤空型三維三階邊界切換電極間距(Electrode Gap)對V-T curve關係 ...................................................79
4.3.5 鏤空型三維三階電極、鏤空型三維二階電極與三維二階電極比較 ...........................................................81
Chapter 5 結論與未來目標..............................84
Reference..................................................88

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