Patent ID: 7495814

Claim:
A raster scanning display device using a diffractive optical modulator, comprising: (a) an optical illumination unit for radiating light, which is emitted from a light source, in a spot beam form; (b) a diffractive optical modulator for causing an element to modulate the spot beam incident from the optical illumination unit, and generate diffracted light whose intensity is adjusted and which has a plurality of diffraction orders; (c) a projection unit for generating an image by projecting the diffracted light incident from the diffractive optical modulator onto a screen in a scanning spot beam form and performing raster scanning in which horizontal scanning and vertical scanning are alternated; and (d) wherein the diffractive optical modulator comprises: a base member; a first reflection part configured such that the first reflection part is supported by the base member, an intermediate part of the first reflection part is spaced apart from the base member to form a space therebetween, and a surface of the first reflection part opposite the base member is formed of a reflection surface to reflect incident light; a second reflection part configured to be spaced apart from the first reflection part between the base member and the first reflection part, and to have a reflection surface for reflecting the incident light; and actuation means for moving the intermediate part of the first reflection part so as to move away from or approach the base member, thus changing intensity of diffracted light that originates from light reflected from the first reflection part and the second reflection part.