臺灣博碩士論文加值系統

本文利用在負型液晶中添加自組織材料製作出雙操作模式之液晶散射元件。實驗中，使用液晶混和物搭配垂直配向玻璃製作液晶樣本，因為自組織材料的特性會在樣本中形成平行液晶的枝條結構，製作完成的樣本在無外加電壓時有高光穿透率，當加電壓時，負型液晶轉向垂直於電場方向，因受到自組織材料枝條的影響，在不同區域液晶的轉向都不同，進而產生光散射效果，實驗結果顯示可藉由改變外加電壓的方式控制樣本的散射效果，此樣本為反向模式的散射元件，在未加電壓時有約90%的光穿透率，穿透率隨著外加電壓提升而下降，約5 V時達到約4%穿透率的散射效果，此為動態操作模式，另外可利用自組織材料特性達成雙穩態模式，利用控制樣本溫度及外加電壓脈衝，可以將液晶穩固在~10%穿透率的散射態模式，雙穩態模式具有省電的功效。

In this study, a liquid crystal (LC) scattering device with dual operation modes was made by adding self-organizing materials (gelator) into negative LCs. In the experiment, the LC sample with vertical alignment layers possessed high transmittance at zero voltage, because the gelator molecules assembled themselves to form sticks and orientated along LCs. When the voltage was applied, the negative LC reoriented to perpendicular to the direction of the electric field. The LCs in different domains reoriented different directions due to the gelaor sticks. Therefore, the light passed the LC sample was scattered. The experimental results show that the scattering effect of the sample can be controlled by modulating the application of voltage. The proposed sample was a reversed mode scattering device. When no voltage was applied, the light transmittance was about 90%. The transmittance decreased as the application of voltage increased. When the voltage of 4 V was applied, the transmittance decreased to ~4% due to the scattering effect. This is the dynamic operation mode. In addition, the sample possesses the bistable mode. The gelator sticks can stabilize LC molecules in scattering state by controlling the temperature of the sample and applying a voltage pulse. The scattering state in the bistable mode had the transmittance of ~40%. The bistable mode LC device can save more power.

摘要......i
Abstract......ii
誌謝......iii
目錄......iv
表目錄......vii
圖目錄......viii
符號說明......x
第一章 緒論......1
1.1 前言......1
1.2 文獻探討......1
第二章 相關理論......8
2.1 液晶的起源......8
2.2 液晶的定義......8
2.3 液晶的分類......9
2.3.1 盤狀分子......9
2.3.2 棒狀分子......10
2.4 液晶物理......14
2.4.1 液晶的光學異向性(optical anisotropic)......14
2.4.2 介電異向性......16
2.4.3 Freedericksz Transition......18
2.4.4 溫度的影響......18
2.4.5 連續彈性體理論......19
2.5 自組織材料特性......20
2.6 DMOAP垂直配向......21
2.7 液晶的相位延遲(Phase Retardation)......22
3.1 材料介紹......25
3.1.1 向列型液晶: HNG732600-100......25
3.1.2 十二氫氧基硬酯酸（12-Hydroxy-Stearic Acid; HSA）......25
3.2 樣本製作......26
3.2.1 調配材料......26
3.2.2 清洗玻璃......26
3.2.3 玻璃基板垂直配向鍍膜......27
3.2.4 樣本製作......27
3.3 實驗架設及量測......29
3.3.1 樣本厚度......29
3.3.2 穿透度-電壓曲線......30
3.3.3 樣本光譜圖......31
3.3.4 轉偏振量測......31
3.3.5 反應時間量測......32
第四章 結果與討論......34
4.1 HSA濃度對樣本光電特性影響......34
4.1.1 不同HSA濃度樣本偏光顯微鏡圖......34
4.1.2 不同HSA濃度樣本的穿透率-電壓曲線......35
4.1.3 不同HSA濃度樣本POM及T-V curve探討......36
4.2 厚度8 μm之 HSA濃度0.15 wt%樣本的各項光電特性......37
4.2.1 樣本光譜圖......37
4.2.2 樣本轉偏振圖......38
4.2.3 樣本反應時間......38
4.2.4 樣本紅光雷射光斑圖......39
4.3 相同HSA濃度但不同厚度樣本的光電特性比較......39
4.3.1 不同厚度樣本偏光顯微鏡圖......39
4.3.2 不同厚度樣本電壓對穿透率曲線......40
4.4 厚度5 μm 之HSA濃度0.15 wt%樣本的各項光電特性......41
4.4.1 樣本光譜圖......41
4.4.2 樣本反應時間......41
4.4.3 樣本紅光雷射光斑圖......42
4.4.4 樣本外加電壓實體圖......42
4.5 雙穩態操作模式......43
第五章 結論......45
參考文獻......46
Extended Abstract......49

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