Image display apparatus

Abstract

An image display apparatus includes an image display device such as, for example, a liquid crystal display panel, having a plurality of dot-shaped picture elements arranged in a two-dimensional pattern, and a diffraction grating disposed on an optical path through which imagewise rays of light emerging from the device travel. To minimize a reduction in quality and contrast of an image displayed by the device, the member has a spatial cut-off frequency chosen to be of a value lying between the sampling frequency, determined by the pitch between picture elements of the image display device, and the Nyquist frequency. For the same purpose, the intensity of .+-.1st order light relative to the intensity of 0-th order light in the diffraction grating is within the range of 60 to 80% at a center wavelength of the image display device, and the sum of the intensity of the 0-th order light and that of the .+-.1st order light relative to that of total diffracted light is equal to or higher than 80% at the center wavelength of the device.

Dependencies are inferred from the claim text.