Image Generators With Compact Optics

Compact image generators that contain illumination sources and electronically controlled spatial light modulators have been invented. Compactness is achieved by folding of the optical paths that link the illumination sources, the spatial light modulators, and the viewing regions into which images are projected. The optical configuration of a device of this type ensures that a large proportion of the light from the illumination source is directed into the viewing region; consequently, the device is unusually energy-efficient for a display device and can, therefore, be operated at a relatively low power (possibly even battery power) for a given display brightness. By virtue of their compactness and low power consumption, these image generators are suitable for head-mounted, helmet-mounted, and eyeglass-mounted displays.