Patent ID: 7295271
Filing Date: 2007-11-13
Classification: G02F

Abstract:
1. A twisted nematic liquid crystal display device for conducting a display operation in Normally Black mode, the liquid crystal display device comprising a liquid crystal cell including two substrates and a liquid crystal layer sandwiched between the two substrates, and two polarizers facing each other with the liquid crystal cell interposed between themselves, wherein the liquid crystal display device further includes a first optical compensator, which is provided between one of the two polarizers and the liquid crystal cell so as to compensate for the wavelength dependence of the angle of rotation of polarized light passing through the liquid crystal layer in a black display state, and a second optical compensator, which is provided between the first optical compensator and that polarizer so as to compensate for the wavelength dependence of the ellipticity of the polarized light passing through the liquid crystal layer in the black display state, wherein the second optical compensator exhibits a retardation, and has a slow axis, within a plane that is defined parallel to the liquid crystal layer, and wherein the in-plane retardation Re wherein the slow axis of the second optical compensator defines an angle of 42 degrees to 48 degrees with respect to orientation directions of liquid crystal molecules in the black display state, the liquid crystal molecules being included in the liquid crystal layer and located near one of the two substrates, which is closer to the first optical compensator.