含奈米雜質之垂直排列液晶元件的光電特性

Electro-Optical Properties of Homeotropic Liquid Crystal Doped with Carbon Nanosolids

戴嘉駿(Chia-Chun Tai)

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/cycu200500001

摘要

近年來在本實驗室的研究中發現：液晶中摻雜微量多壁碳奈管能有效地降低液晶樣品的臨界電壓與驅動電壓，而該雜質的添加卻不至於增加離子電荷效應的發生。在本論文中，我們針對液晶摻雜碳奈米固體系統，探討在直流電場或交流電場的影響下，垂直排列液晶盒的臨界電壓與驅動電壓，以及其時變光強與時變電容。實驗結果顯示：在直流偏壓下，有摻雜碳奈米固體的垂直排列液晶盒，其臨界電壓與驅動電壓皆有明顯下降的現象。另外在交流偏壓作用下，不同的交流頻率會影響臨界電壓與驅動電壓—當頻率越大時，液晶的臨界電壓與驅動電壓會隨著增加—同時摻雜碳奈米固體的樣品在特定的電場頻率下，還會有臨界電壓與驅動電壓下降的情形。除此之外，實驗中也發現液晶中微量碳奈米固體的摻雜不但不會增加離子電荷，並且有抑制離子電荷效應的現象。

關鍵字

液晶 ； 碳60 ； 碳奈管 ； 垂直排列

並列摘要

In the pass two years, research projects conducted in our laboratory have indicated that carbon-nanotube dopant in liquid-crystal cells can effectively reduce the threshold and driving voltages, and yet the dopant would not enhance the ion-charge effect. In this work, we investigated several physical properties, such as the threshold voltage, driving voltage, time-evolved transmittance and time-evolved capacitance, of vertical-aligned liquid-crystal cells doped with carbon nanosolids in the presence of dc or ac voltage. Experimental evidence points out that the doped cells have lower threshold and driving voltages under external dc voltage. Furthermore, in the presence of ac voltage, the threshold and driving voltages of the cells are affected by the frequency. The higher the frequency is, the higher the threshold and driving voltages of the cells become. In addition, the threshold and driving voltages of the doped cells become lower in some specific frequency. Moreover, we found that doping carbon nanosolids in liquid crystal does not increase ion charge. In contrast, it suppresses ion-charge effects.

並列關鍵字

Homeotropic ； Fullerenes ； Liquid crystal ； Carbon nanotube

參考文獻

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