ILLUMINATION DEVICE, IMAGE DISPLAY DEVICE AND PROJECTOR

摘要

PROBLEM TO BE SOLVED: To provide an illumination device capable of easily forming an irradiation area and uniforming light quantity distribution, and to provide an image display device and a projector using the illumination device. SOLUTION: The illumination device comprises: a laser beam source 12R as a light source part of emitting coherent light; and a diffraction optical element 13R which diffracts the coherent light emitted from the light source part and causes primary diffraction light L1 as diffraction light to travel to a surface S2 to be irradiated, wherein the diffraction optical element 13R is arranged such that coherent light is made incident obliquely relative to a perpendicular line N to an incident surface S1 as the reference surface for arranging the diffraction optical element 13R and causes zero-order light L0 as light besides the diffraction light among light emitted from the diffraction optical element 13R to travel to a position besides the surface S2 to be irradiated. COPYRIGHT: (C)2009,JPO&INPIT