Patent ID: 6942345
Filing Date: 2005-09-13
Classification: G03B

Abstract:
1. A projection type image display apparatus comprising: image display elements; an illuminating optical system for illuminating the image display elements with illuminating light from a light source; and a color separating and synthesizing optical system for separating the illuminating light from the illuminating optical system into a plurality of color lights, making the respective color lights enter the image display elements provided for the respective color lights, and synthesizing image lights of a plurality of colors emerging from said image display elements; a projection optical system for projecting and displaying the image lights synthesized by the color separating and synthesizing optical system; a light directing element disposed between the illuminating optical system and the color separating and synthesizing optical system, for reflecting the illuminating light from the illuminating optical system at a reflectance approximate to about 100%, directing it to the color separating and synthesizing optical system and transmitting there through the image lights from the color separating and synthesizing optical system to the projection optical system; polarizing elements disposed between the color separating and synthesizing optical system and the image display elements for transmitting only a particular polarized component light there through; and an auxiliary optical element for refracting and transmitting there through the image lights emerging from the light directing element, said auxiliary optical element being disposed between the light directing element and the projection optical system with an air space provided relative to the light directing element, wherein the optical path of the illuminating light and the optical paths of the image lights in the light directing element and the color separating and synthesizing optical system differ from each other, and wherein the light directing element is formed into a wedge shape.