Liquid crystal light modulation device and liquid crystal light

Abstract

The present invention provides a liquid crystal light modulation device which has a cell comprising a pair of substrates at least one of which is transparent and which have electrodes and are opposed through a spacer, a ferroelectric liquid crystal layer which is enclosed in said cell and which has a phase series where a nematic phase (N*phase) or an isotropic phase (I phase) is shown on a just higher temperature side of a ferroelectric phase (smectic C* phase, Sc* phase) and two polarizing plates which sandwich the cell therebetween, liquid crystal molecules at one interface between the liquid crystal layer and the substrate being fixed to the substrate more weakly than liquid crystal molecules at the other interface between the liquid crystal and the substrate wherein the liquid crystal molecule weakly fixed is fixed to such an extent that inversion of spontaneous polarization of the liquid crystal molecule occurs upon application of an electrical field to the liquid crystal layer through the electrodes, orientation of the liquid crystal molecule at one interface and orientation of the liquid crystal molecule at the other interface can be either the state (a) of being nearly parallel to each other or the state (b) of crossing each other by the inversion of the spontaneous polarization and the two polarizing plates are arranged so that light transmittance is lower at the state (a) than at the state (b).