垂直排列-扭曲向列液晶显示的阈值特性

液晶与显示 , 2001, 16(2): 97-103. doi: 10.3969/j.issn.1007-2780.2001.02.003

垂直排列-扭曲向列液晶显示的阈值特性

朱新羽 ^1, , 荆海 ^2, , 王宗凯 ^3, , 凌志华 ^4, , 黄锡珉 ^5,

基金项目: 吉林省科技厅科技攻关项目(970103-01) 国家自然科学基金(69876040) 中国科学院资助项目(YK95-A1-502)

Threshold Characteristics of Homeotropic-twisted Nematic Liquid Crystal Display

Keywords： free energy , homeotropic-twisted nematic liquid crystal , threshold voltage ,

从液晶体系的总自由能出发，通过欧拉-拉格朗日方程组的推导，得到了手性向列相液晶从垂直排列状态转变成平面扭曲排列时的Freedericksz转变阈值电压公式Vth=π×(k33)/(ε0｜Δε｜)1-4(k22)/(k33)2(d)/(P0)2, 并通过C-V特性验证了阈值电压公式的正确性，同时讨论了器件阈值电压与盒厚-螺距比d/P0的关系及其物理意义。

Based on Frank continuum theory, the threshold voltage formula of Freedericksz transition in homeotropic-twisted nematic mode is deduced in this paper. The threshold voltage is expressed by π(k33ε0｜Δε｜)1-4(k22k33)2(dP0)2and verified by calculated C-V characteristics. The reason that threshold voltage decreases with the increase of d/P0ratio is also discussed.

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