Electro-optical device utilizing a liquid crystal having a spontaneous polarization

摘要

A high-performance liquid crystal display includes a pair of substrates and a liquid crystal cell containing a ferroelectric or antiferroelectric liquid crystal. TFTs or a ferroelectric thin film is formed on one substrate. A given amount of electric charge is supplied into the liquid crystal inside the pixel electrodes. After the supply, the charge is retained under a high-resistivity condition. The ratio of the area of parts of the liquid crystal material in a first state to the area of parts in a second state is controlled by the amount of electric charge supplied, thus achieving a wide gray scale. The fast response and the wide viewing angle intrinsic in the liquid crystal are fully exploited. Further, a liquid crystal display using a liquid crystal material consisting either of a liquid crystal material showing ferroelectricity or anfiferroelectricity or of a high polymer in which such a liquid crystal material is dispersed is disclosed. The liquid crystal material is so selected that it shows appropriate spontaneous polarization. The time for which an electric field is applied to the liquid crystal material is controlled to obtain a gray scale.