具有較大液晶顆粒的聚合物分散液晶薄膜之光電效應研究

Anomalous electrooptical effect of polymer dispersed liquid crystal films with large liquid crystal droplets

林金蔚(Chin-Wei Lin)

指導教授 ： 莫定山

崑山科技大學/工程學院/電子工程研究所/碩士(2008年)

https://doi.org/10.6828/KSU.2008.00046

摘要

本論文研究重點為利用極弱的紫外光照射於液晶—聚合物混合溶液中使材料均勻聚合硬化及相分離，形成具有較大液晶顆粒分散的薄膜，並量測其電壓－穿透率的關係曲線。從實驗量測結果中得知此薄膜光電特性曲線與一般正常的聚合物分散液晶薄膜有相當大的不同。因此，我們改變聚合物材料、液晶－聚合物混合溶液的濃度比例與樣本的厚度，並使用不同角度入射的偏振光來偵測此薄膜光電特性。藉由上述實驗的結果中提出一個模型來解釋，藉由『電流體動力學理論』可以獲致相符的推論結果。最後我們期許這樣的研究應用在實際的相關科學領域方面。

關鍵字

聚合物分散液晶薄膜 ； 光電效應 ； 電流體動力學 ； 液晶顆粒

並列摘要

In this thesis, we successfully fabricated the polymer dispersed liquid crystal (PDLC) films with very large liquid crystal (LC) droplets through phase separation process cured under very weak ultraviolet (UV) light. The electro-optic properties of our samples were investigated and the results were very different with normal PDLC films, especially in the high voltage regions. The novel phenomenon we observed were resulted form the electrohydrodynamics (EHD) instabilities occurred inside the LC droplets. A series of experiments with different conditions; changed polymer materials, changed LC-polymer concentration, changed films thickness, changed angle and polarization direction of incident light; were completed. All the experimented results were accordant with our inference mentioned above.

並列關鍵字

PDLC ； electrooptical effect ； electrohydrodynamics ； EHD ； liquid crystal droplets

參考文獻

[2] B. Bahoadur, Liquid Crystal-Ampplications and Uses,

[3] P. gde Gennes and J. prost, The Physics of Liquid

[4] M Blinov and V.G. Chigrinov, “Electrooptic Effects in

Liquid Crystal Materials”, Springer-Verlag, New York

[5] P. G. de Gennes and J. Prost, “The physics of Liquid