Projection type display apparatus with means for supplying an air cooling stream to a gap between a light receiving surface of a prism and a third surface of a closed triangular prismatic housing

Abstract

A projection type display apparatus includes: a reflective polarizing plate for each color light which transmits each of R light, G light and B light having a P polarized component subjected to color separation by a color separation optical system therethrough, allows each transmitted light to enter a corresponding reflective liquid crystal panel for each color light, and reflects image light of each color having an S polarized component which has been subjected to light modulation in accordance with an image signal of each corresponding color light by the reflective liquid crystal panel for each color light; a transmission type polarizing plate for each color light which removes an unnecessary polarized component from the image light of each color reflected by the reflective polarizing plate for each color light; a color combination optical system which subjects the image light of each color transmitted through the transmission type polarizing plate for each color light to color combination; and a projection lens, wherein the transmission type polarizing plate for each color light is air-cooled by air-cooling means when the transmission type polarizing plate for each color light faces each incidence surface of the color combination optical system.