Patent ID: 7052141

Claim:
A projector, comprising: a light modulator having a rectangular image forming region to form an optical image by modulating an incident luminous flux in response to image information and microlenses disposed on an incident side of the image forming region so as to correspond to pixels; a projection optical system to project modulated light from the light modulator; a light source unit having an arc tube, an ellipsoidal reflector to reflect a luminous flux emitted from the arc tube, and a collimator lens to collimate the luminous flux reflected by the ellipsoidal reflector; a luminous flux splitting optical element formed by arranging a plurality of small lenses in a matrix form within a surface perpendicular to an illumination optical axis to split the luminous flux output from the light source unit into a plurality of partial luminous fluxes; and a superposing lens to superpose the respective partial luminous fluxes split by the luminous flux splitting optical element on the image forming region of the light modulator, the collimator lens being disposed in a position where a diameter of the luminous flux reflected by the ellipsoidal reflector is equal to or more than a short side dimension and equal to or less than a long side dimension of the image forming region, and effective luminous flux transmitting regions of the luminous flux splitting optical element and the superposing lens being set in rectangular shapes having side dimensions equal to or more than the short side dimension and equal to or less than the long side dimension of the image forming region.