Patent attributes
The present invention provides a technique for readily changing the design of a projector. A projector comprises: an illumination optical system; a light modulation device; a projection optical system; and a base frame for mounting a plurality of optical components disposed on a light path from the optical illumination system to the projection optical system. The illumination optical system 300 comprises: a light source 20; a lens array 320; and a superimposing lens system 370. The base frame includes a positioning section for positioning the superimposing lens system 370. The superimposing lens system 370 includes at least two lenses 371 and 372. The first lens 371 is provided at a position nearest to the light source and mainly determines an F-number of the illumination optical system. The second lens 372 is provided at a position furthest from the light source and mainly determines a magnification of the illumination optical system.