Patent ID: 9377759
Filing Date: 2016-06-28
CPC Classification: G02B,G03B,G03H,H04N

Claim Text:
1. An illumination device comprising: an optical device including a hologram recording medium capable of reproducing an image of a reference member on an illumination zone, the optical device varying an incidence angle of a coherent light beam at each position on the illumination zone with time; and an irradiation unit configured to irradiate the coherent light beam to the optical device so that the coherent light beam scans the hologram recording medium, wherein the irradiation unit comprises wavelength ranges in different directions; wherein the hologram recording medium comprises a plurality of recording areas corresponding to a plurality of coherent light beams reflected by the scanning device, respectively, and wherein each of the plurality of recording areas comprises an interference fringe that diffracts a coherent light beam of the corresponding wavelength range; wherein each of the plurality of coherent light beams is scanned on the corresponding recording medium; and wherein the plurality of coherent light beams diffracted by interference fringes of the plurality of recording areas repeatedly illuminate at least a part of the illumination zone to reproduce the image of the reference member.