Patent ID: 7066607

Claim:
A projection type display optical system, comprising: a light source; an image display means comprising a digital micromirror device which receives a light beam emitted from the light source; and an illumination unit installed in between the light source and the image display means, and comprising: a rod lens operating as an optical device for unifying the brightness distribution of an incident light ray from the light source and emitting the brightness unified light ray; a first lens for transmitting the emitted light ray from the rod lens; an optical element on which the transmitted light ray from the first lens incidents; and a projection part for magnifying and projecting an image formed on the image display means onto a screen, wherein the first lens and the optical element are set in such a manner that an optical axis of the optical element and an optical axis of the first lens are parallel but do not coincide with each other, whereby a surface image that is formed, when the emitted light ray from the rod lens is transmitted through the first lens and the optical element, is not inclined to the surface of the image display means.