PROJECTION APPARATUS USING SPATIAL LIGHT MODULATOR WITH RELAY LENS AND DICHROIC COMBINER

摘要

A digital projection apparatus (10) for projection of a multicolor image includes a magnifying relay lens assembly (28) as part of the light modulation assembly (38) for each component color. The relay lens assembly (28) increases the effective f/# of incident light to the V-plate assembly (25) or V-prism assembly (27) that serves as dichroic combiner, used to combine modulated light of each color from each light modulation assembly (38) in order to form the multicolor image. The magnifying relay lens assembly (28) also provides a reduced working distance for the projection lens (32), allowing a lower-cost design and facilitating substitution of the projection lens (32) best suited for a display surface (40).