JPS6415720A - Liquid crystal display element - Google Patents

Abstract

PURPOSE:To obtain a liquid crystal display element of a sharp black and white display by providing a pair of polarizing plates to the outside of a cell formed by sandwiching a liquid crystal between a pair of transparent electrode substrates and providing liquid crystal layers which have the same twist angle and are reverse in spiral direction between one electrode and polarizing plates. CONSTITUTION:A pair of the polarizing plates are provided on the outside of the liquid crystal cell disposed to have 200-300 deg. twist angles between both electrodes at the time of impressing no voltage to the cell. The liquid crystal layers which have the same twist angle and are reverse in the spiral direction are disposed between the one electrode and the polarizing plates in such a manner that the molecular axis of the parts brought into contact with each other by holding the electrodes inbetween intersect nearly orthogonally with each other. The two liquid crystal layers are used but electrodes are not required for the 2nd liquid crystal layer. The layer thickness of both is set the same and the product DELTAn.d of the double refractive index DELTAn and the layer thickness d is set in a 0.5-2.0mum range. A pair of the polarizing plates are so disposed that the axes of polarization thereof intersect nearly orthogonally with each other. The colorful display is thus made by using filters together with the black and white display.