Liquid Crystal Materials for Laser Beam Steering

摘要

Several new liquid crystal compounds have been developed for laser beam steeringapplication. The asymmetric diakyl diphenyl-diacetylenes exhibit a low melting temperature, wide nematic range, high birefringence, low viscosity and small heat fusion enthalpy. They are excellent host materials for forming eutectic mixtures except for the small dielectric anisotropy. To enhance dielectric anisotropy, some polar diphenyl-diacetylenes and tolanes, and a new series of the nitro-azo-benzene dyes have been considered. Among these polar compounds, the nitro-azo-benzene dyes exhibit a mesogenic phase with melting temperature at about 80 deg C huge dielectric anisotropy, excellent solubility and relatively low viscosity. The solubility and viscosity of these dyes are about one order to an asymmetric diphenyl-diacetylene binary mixture reduces its threshold voltage from 3.5 to 1.7 V sub rms. (Author).