Patent ID: 7188952

Claim:
A reflection-type micro display projection system comprising: a light source for emitting a light beam; an optical system for transmitting the light beam emitted from the light source; a reflection-type liquid crystal display panel for reflecting the light beam transmitted through the optical system and outputting the light beam as image information; a projection lens for magnifying and projecting the image information; and a screen for displaying an image corresponding to the image information magnified and projected by the projection lens, wherein n×sin β=sin α when the incident angle of the light beam, which is output from an illumination lens of the optical system and input to a polarization beam splitter on the basis of the normal of the boundary face of the polarization beam splitter, is α, the refractive angle of the light beam refracted inside the polarization beam splitter is β, and the refractive index of the polarization beam splitter is n, the refractive index n being larger than 1.6 and smaller than 2.0, wherein the refractive angle β of the light beam refracted inside the polarization beam splitter is smaller than 7.5°.