向列液晶层中的指向波实验

在指向矢垂直于基片排列的液晶盒中,作者用机械方法激发出孤立波似的指向波。本文给出一组用闪光法记录的指向波的传播过程的照片,在白光照明时,观察到一些黑线的传播,并给出这些黑线的位置和速度对时间的相依曲线。从会聚偏振光干涉图得到的结果表明,这些黑线代表指向矢垂直于基片的排列状态,并且在黑线两侧明显地观察到液晶的散射光。用单色光记录了波的传播过程,并在一维假定下算出指向矢的空间分布曲线,最后给出作者关于指向波的物理模型的讨论。关键词：

EXPERIMENTS ON DIRECTOR WAVE IN NEMATIC LIQUID CRYSTAL

In a homotropic nematic cell, a solitary-like director wave is excited by a mechanical method. A series of photographs of the wave propagation process are obtained. When white light is used, we noticed the propagation of some dark lines along the cell, and we got the plot of the positions and velocities of the dark lines vs time. According to the results obtained from the interference patterns of focused polarized light, it was shown that the dark lines correspond to a perpendicular alignment state of the director, in addition, the scattered light by liquid crystal is observed clearly on the two sides of dark lines. From the wave propagation process recorded by monochromatic light, and by using an one dimension postulat, we calculated the spatial distribution of the directors. Finally, some discussion on the physical model of the director wave is given.