Homogeneous illumination of transparencies in optical image projector - merging cones of light from closely-spaced array of lamps or optical fibres onto slide or liquid crustal shutter.

摘要

A transparency (8) is placed in the field of the converging beams (5) from an array of miniature lamps (1) oriented so that the cone of light (5) from each lamp covers the entire entry face of the objective lens (6). The cones of light merge at a particular distance (7) from the plane of the array. Diminution of brightness towards the edges of the projected image can be countered by rearrangement of the light sources in a concave array instead of a plane array. USE/ADVANTAGE - Esp. in small vehicles, handling equipment and industrial robots, smaller and lighter projector utilises max. number of individual light sources.