Projection optical system having a wedge prism

Abstract

A projection optical system includes a light source emitting light, a light valve with a surface in front of the light source, and a wedge prism disposed in the optical path from the light source to the light valve. By means of the wedge prism with different sectional thickness, the optical path and focus position of the light beam can be corrected. Therefore, the distortion produced by oblique incidence on to the light valve can be improved such that the light optical focus on the surface of the light valve to achieve the improvement of light spot on light valve and raise the uniformity, collection efficiency, and brightness.

Dependencies are inferred from the claim text.