High Efficiency Light-Valve Projectors and High Efficiency Laser Light Sources

The optical efficiency of a liquid-crystal light-valve projector is determined by the optical design, the method of modulation and the efficiency of the light source. A projector has been built with an efficient modulation technique. It employs unpolarized light by using a diffraction grating formed in the liquid crystal. The diffraction technique uses a Schlieren optical system. The light sources tested have been xenon arcs, metal halide arcs and efficient solid-state lasers. The optical system reduces laser speckle significantly when laser sources are used. All combinations exceeded 3 lumens per watt for white light Experimental results of the combinations will be given. This modulation technique obtains a high contrast ratio with smaller panels than can be achieved with rotation-of-polarization light valve projectors.

Published

1995-09

Content type

Original Research

DOI

10.5594/M00513

ISBN

978-1-61482-923-2