液晶光学双稳态及自振荡研究

Optical Bistability and Self-Oscillation in a Nematic-Liquid-Crystal Film

研究了一种扭曲向列相液晶电光调制器的电光特征，讨论了在两种不同偏振配置下液晶对光行为的影响及两种电光特性的区别，实现了液晶调制光学双稳态及多种光逻辑工作状态，发现了一种新的自振荡，观察到振荡的阈值现象和振荡周期对偏压的依赖关系．由于液晶非线性系数大，实验中只需中等强度的连续激光，避免了使用高强度脉冲激光而产生的脉冲间的不确定性。

In this paper,the electro-optical characteristics of a nematic liquid crystal modulator have been studied experimentally and the differences between two kinds of polarization arrangements of the behaviour of polarised light affected by the liquid crystal have been discussed.Experimental rehults show that the modulator can exhibit optical bistability and other operating mode.A new selfoscillation was observed.The oscillation periods depending on the bias voltages have been measured at various bias voltages.Experiments only need moderaedpower CW laser.