COLOR SEPARATION AND SYNTHESIS OPTICAL SYSTEM, IMAGE DISPLAY OPTICAL SYSTEM, AND PROJECTION TYPE IMAGE DISPLAY DEVICE

摘要

PROBLEM TO BE SOLVED: To solve the problem that low polarization purity decreases contrast when image display elements for respective colors are lit with respective polarized light beams by using a polarization beam splitter. SOLUTION: The polarization separation characteristics of a 1st polarization separation surface and a 2nd polarization separation surface are made different from each other by providing: a color separation means 6 for separating illumination light into a 1st color light beam G and 2nd and 3rd color light beams R and B; a 1st polarization separation surface 11a which makes different the optical path of incidence of the 1st color light on a 1st image display element from the color separating means and the optical path of projection from the 1st image display element 12g to a color synthesis means through a polarization separation operation, and the 2nd polarization separation surface 11b which separates the 2nd and 3rd color light beams from the color separation means and makes different the optical paths of incidence of those color light beams on 2nd and 3rd image display elements 12r and 12b and the optical paths of projection from the 2nd and 3rd image display elements to a color synthesis means through a polarization separation operation.