臺灣博碩士論文加值系統

藍相液晶( Blue phase liquid crystal )是一個擁有雙螺旋柱體( Double twist cylinder )晶格結構的液晶分子，其光電機制是當施予外加電場時，會誘發雙折射現象，也就是克爾效應( Kerr effect )，因此我們所討論的液晶盒厚度造成克爾常數的改變，對於觀察藍相液晶的光電特性也是重要的參考，並對於未來應用在藍相液晶顯示器相關產品上相當有幫助。
在本論文中，我們使用不同厚度的藍相液晶盒，經由垂直場驅動，液晶盒擺放在與入射光夾45° 與60° 的位置，量測出在斜向入射光下的相位φ跟電壓V關係，並利用相位公式求得雙折射δn。最後，我們再根據克爾效應的公式進行整理，得到在低電場時雙折射δn會與外加電場平方E^2 呈現線性關係，此實驗結果與理論值相符。求得克爾常數後，可以發現不同的液晶盒厚度會對克爾常數造成影響。

Blue phase liquid crystal ( BPLC ) has a double helical cylinder lattice structure. The electro-optical mechanism of BPLC is the electric-field-induced birefringence, δn, known as the Kerr effect. In this study, we experimented and discussed the relation between the Kerr constant and cell thickness. The result is an important reference for BPLC electro-optical property, and may have a great help for applications of BPLC in the future.
In this paper, we changed the thickness of the cell and drove it by vertical electric field. The BPLC cells were placed in 45? and 60? with respect to the incident light. Measuring the relationship between the phase retardation φ and driving voltage V, and using the φ - V relation, we obtained the induced birefringence δn. Finally, we obtained that the δn is proportional to E^2. The results match the Kerr effect formula. Kerr constant is calculated, and we found that the cell thickness will affect the Kerr constant.

目錄

中文摘要 i
英文摘要 ii
誌謝 iii
目錄 iv
圖目錄 vi
表目錄 vii
第一章 緒論 1
第二章 液態晶體材料簡介 3
2.1液晶的發展歷史 3
2.2液晶的種類 4
2.3液晶分子的配向 9
2.4液晶的光學特性 10
2.4.1介電異方性 10
2.4.2雙折射率 11
2.4.3彈性係數 12
2.4.4黏滯係數 13
第三章 藍相液晶介紹 14
3.1藍相液晶的發現 14
3.2藍相液晶的結構 15
3.3藍相液晶的光電特性 18
3.4藍相液晶溫寬拓展技術 18
3.5高分子穩定型藍相液晶 20
3.5.1高分子穩定型藍相液晶的克爾效應 21
3.6藍相液晶顯示器 22
第四章 實驗架構 23
4.1液晶材料參數介紹 23
4.1.1改變溫度下變化情形 23
4.1.2施加電壓下變化情形 25
4.2相位量測系統介紹 27
4.2.1斜向入射量測方法 29
第五章 量測結果與原理討論 30
5.1相位量測結果 30
5.1.1斜向入射角度與液晶盒厚度關係 32
5.2藍相液晶折射率橢球形變討論 33
5.3液晶雙折射率與電場關係 35
5.4克爾常數討論 37
第六章 結論和未來展望 38

參考文獻 39
附錄：A. 中國液態晶體研討會論文發表 41

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