Patent ID: 7165849

Claim:
A projector for projecting an image on a projection surface through a projection lens, including an active type distance measurement device which obtains distance measurement data corresponding to a distance between said projection lens and said projection surface, said distance measurement device comprising: a light emitting element for emitting a distance measurement light; a light emitting lens for directing said distance measurement light from said light emitting element to said projection surface; a light receiving lens for transmitting said distance measurement light reflected from said projection surface; and a light receiving element for receiving said distance measurement light passed through said light receiving lens, wherein an optical axis of said distance measurement light from said light emitting lens to said projection surface and an optical axis of said light receiving lens are parallel to each other and inclined a specified angle with respect to an optical axis of said projection lens such that light that is diffused in transiting the light emitting lens and specularly reflected by the projection surface does not enter said light receiving element while entering said light receiving lens.