Illumination device and projector

Abstract

An illumination device includes a light source device, a uniformization optical system which uniformizes the illuminance distribution of light from the light source device on a region to be illuminated, and a diffraction optical element which is provided in an optical path between the light source device and the uniformization optical system, and rotates around a predetermined rotation axis. The diffraction optical element includes a first region which forms a first illuminance distribution, and a second region which is provided at a position different from the first region around the rotation axis, and forms a second illuminance distribution different from the first illuminance distribution.

Dependencies are inferred from the claim text.