Patent ID: 9733462
Date: 2017-08-15
CPC Classifications: G02B

Claim:
1. A scanning apparatus comprising: a light source; a spatial light modulator configured to have a flat first reflection surface and to modulate an incident beam of light on the first reflection surface; an illumination lens configured to irradiate the spatial light modulator with a beam of light from the light source and to refract a principal ray of a beam of light modulated by the spatial light modulator so that an angle between the principal ray and an optical axis of the illumination lens decreases, the first reflection surface being located in a back focal plane of the illumination lens; and a first reflector that directs, toward the illumination lens, a beam of light by reflecting the beam of light multiple times between the illumination lens and a front focal plane of the illumination lens, the beam of light being modulated by the spatial light modulator and entering through the illumination lens, wherein: the illumination lens converts a beam of light reflected on the first reflection surface into a convergent beam, and the first reflector converts an incident beam of light into a divergent beam that has an inverted travelling direction and has been shifted in a direction perpendicular to the optical axis.