LICHTVENTIL-PROJEKTOR MIT ERHOEHTER LICHTAUSBEUTE.

摘要

A multiple light valve (MLV) projector apparatus for producing a color display includes two separate light valves of the Schlieren dark field type. One of the light valves produces a first primary color, for example green, and the other light valve, including an array of lenslets (19) and a cooperating input mask (60) having slots (62,66) extending in orthogonal directions, produces two other primary colors, for example red and blue. In such an apparatus the output brightness is usually limited by the red light output. An improved two-color light valve is provided having an input (and complementary output) mask (60) which optimizes the transmission of the first, second and third diffraction orders through the slots (62) in the portion of the input mask which transmits red light, these slots being asymmetrically disposed relatively to the lenslets in the corresponding direction. Such an optimization provides a substantial increase in red light output compared to a conventional input mask.