High Birefringence and Low Viscosity Liquid Crystals with Negative Dielectric Anisotropy

摘要

Fast response time is critical for reducing the image blurs in LCD TVs. A straightforward approach is to use thin cell with a high birefringence and low viscosity liquid crystal material. We have synthesized and evaluated the physical properties of some high birefringence, laterally difluorinated terphenyl compounds and mixtures. These mixtures exhibit a high birefringence (DELTA n approx 0.24) in the visible spectral range and a relatively low viscosity. When doped in commercial mixtures, the difluoro terphenyl compounds enhance the mixture's birefringence while causing almost no penalty to the rotational viscosity. These mixtures are particularly attractive for thin cell LCDs to achieve fast response time.