Electro-optically - active material combinations and - an electro-optically active device with the use of such material compositions

摘要

Thin flat panel display devices utilize optical polarization elements to control the amount and location of light transmitted through liquid crystal media having electric field controllable birefringence properties. Nematic liquid crystal compositions are provided, particularly adapted for use in such display systems, that demonstrate electric field controllable birefringence properties, for example, from above room temperature to about -30 DEG Centigrade. These compositions include binary mixtures of p-toluylidene p-n-butylaniline with p-n-butoxybenzylidene p-n-butylaniline or pentyl p-anisylidene p-aminophenyl carbonate with p-ethoxybenzylidene p-n-butylaniline. Ternary compositions may be formed by adding ionizable materials.