介电各向异性对铁电液晶光电特性的影响

Effect of Dielectric Anisotropy on Optoelectric Characteristics of Ferroelectric Liquid Crystal

提出了一种描述铁电液晶(FLC)介电各向异性的电路模型.分析了FLC介电各向异性对开关响应时间、特征时间、特征电压和极化反转电流的作用,以及铁电扭矩和介电扭矩对光透射率的影响。模拟分析显示,延迟时间随驱动电压幅度变化存在最小值,特征时间(特征电压)随二轴参量的提高而增加(减小).随二轴参量增大,介电扭矩的贡献将超过铁电扭矩;相应的极化反转电流由双极性转变为单极性;透射率无"明态"和"暗态"的交替,且峰值逐步降低.

A circuit model of ferroelectric liquid crystal （FLC） was proposed to study me effects of biaxial anisotropy on switching time, characteristic time, characteristic voltage and polarization reversal current, and those of ferroelectric torque and dielectric torque on light transmittance. The results indicate that the delay time has the minimum value as the drive voltage amplitude varies, and the characteristic time （voltage） increases （decreases） as the biaxial anisotropy increases. When the value of biaxial anisotropy is large enough, the effect of dielectric torque exceeds ferroelectric torque; the corresponding polarization reversal current becomes unipolar rather than bipolar; and the alternating change in light transmittance between ＂bright＂ and ＂dark＂ vanishes, and the peak value of light transmittance decreases gradually.