ILLUMINATION DEVICE, PROJECTION DEVICE AND PROJECTION TYPE VIDEO DISPLAY DEVICE

摘要

PROBLEM TO BE SOLVED: To provide an illumination device capable of effectively making speckle inconspicuous.SOLUTION: An illumination device 40 includes: an optical element 50 including a first light diffusing element 55a and a second light diffusing element 55b; an irradiation device 40 configured to irradiate the optical element 50 with plural types of coherent light having different wavelength regions, so that first coherent light La having a first wavelength region scans over the first light diffusing element 55a and second coherent light Lb having a second wavelength region scans over the second light diffusing element 55b; a synthesizing device 70 configured to synthesize the first coherent light from the first light diffusing element and the second coherent light from the second light diffusing element; and an integrator rod 80 configured to receive the first coherent light and the second coherent light synthesized at the synthesizing device.