Liquid crystal display device incorporating phase difference plate and liquid crystal layer capable of improving viewing angle dependence

Abstract

A liquid crystal display device incorporates two phase difference plates stacked together and disposed between a liquid crystal display element and a pair of polarizers, the liquid crystal display element being formed by sandwiching a liquid crystal layer between a pair of electrode substrates, and the polarizers being disposed on one side of the liquid crystal display element. Since the principal refractive indices n, n, and nof the phase difference plates are such that n<n<n, the phase difference plates exhibit positive refractive index anisotropies. The principal refractive index ninclines to the normal to the surfaces of the phase difference plates about one of the principal refractive indices nor nthat is parallel to the surfaces. In addition, the refractive index anisotropy an of the liquid crystal material constituting the liquid crystal layer is specified to vary with wavelengths of rays of light within a range that allows no viewing-angle dependent coloration to occur on a liquid crystal screen. This eliminates viewing-angle dependent phase differences that, otherwise, would occur to the liquid crystal display element, and especially prevents the coloring phenomenon efficiently on the liquid crystal screen that, otherwise, would, occur with larger viewing angles.