Optical device and projection display

摘要

An optical device which is suitable for use in a projection display comprises a spatial light modulator 40, such as a liquid crystal device, with a microlens array 42 disposed on its front surface. The microlenses 58 are of convergent type, such as lenticules. The spatial light modulator is of the reflective type and comprises a plurality of rear reflectors 59, each of which has convergent optical power in at least one direction. The reflectors 59 are arranged such that, for a given direction of illumination, each reflector 59 forms an image of the aperture A of a microlens on the aperture B of another microlens or at a different position on the same microlens. When used in, for example, a projection display, light losses caused by vignetting are reduced.