扭轉向列型液晶摻雜碳奈米雜質在交流電場作用下的光電特性

Electro-Optical Properties of Twisted Nematic Liquid Crystal Doped with Carbon Nanosolids in an AC Electric Field

石裕誠(Yu-Cheng Shih)

指導教授 ： 李偉

中原大學/理學院/應用物理研究所/碩士(2005年)

https://doi.org/10.6840/cycu200500002

摘要

本論文研究乃藉由系統整合，將具有GPIB及DAQ介面的儀器統整而形成一個量測系統，並根據需求編寫程式以進行自動化控制，測量摻雜碳奈米固體（富勒烯或碳奈米管）的扭轉向列型液晶盒在外加交流電場作用下的時變光電特性。
我們發現扭轉向列型液晶盒的幾項特性：一、不論在低頻或高頻的區段，於液晶中摻雜碳奈管均能有效地降低液晶盒所需的驅動電壓；二、外加高頻交流電場時，液晶樣品需要較高的驅動電壓，且驅動電壓會隨著外加頻率的增加而變大；三、在液晶中摻雜碳奈管可以有效地減少液晶樣品的升起時間；然而就整體反應時間而言，純液晶樣品具有最優良表現；除此之外，外加交流電場的頻率會對液晶盒的反應時間造成影響。

關鍵字

扭轉向列型液晶 ； 交流電壓 ； 碳奈米雜質

並列摘要

We present the results on the electro-optical properties of 90° twisted nematic cells of pristine liquid crystal and liquid crystal doped with carbon nanosolids (buckminsterfullerene or carbon nanotubes) in the presence of ac voltage under an automatic measurement system, including GPIB- and DAQ-interfaced instruments.
We found several characteristics of twisted nematic liquid-crystal cells: First, doping with carbon nanotubes into liquid-crystal cells can effectively reduce the driving voltage in both the low and high frequency regimes; Second, all kinds of the cells require higher driving ac voltage when the applied ac voltage is in the high-frequency range, and the driving voltage increases with the frequency; Third, the liquid-crystal cells doped with carbon nanotubes possess the shortest rise time, but the pristine liquid-crystal cells have the shortest total response time. In addition, the frequency of ac voltage influences the response time of a liquid crystal cell.

並列關鍵字

twisted nematic liquid crystal ； ac voltage ； carbon nanosolids

參考文獻

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