Patent ID: 8848276
Filing Date: 2014-09-30
Classification: G02B

Abstract:
1. An optical-path conversion device comprising: a plate-shaped phase modulation mask in which a plurality of phase modulation parts are discretely formed for providing phase modulation to light passing through, and a first light-transmission part is formed for transmitting the light; and a plate-shaped light-shielding member in which a plurality of light-shielding parts are discretely formed for blocking the light, and a second light-transmission part is formed for transmitting the light, wherein the phase modulation mask and the light-shielding member overlap each other at least in part, when viewed in an incident direction of the light, at least one of the phase modulation mask and the light-shielding member is movable in an intersection direction which intersects with the incident direction, each of the phase modulation parts has a curved surface for providing the phase modulation, each of the light-shielding parts is formed by forming, on a board which transmits the light, a light-shielding film which has a light-shielding property, and a plate surface of the phase modulation mask and a plate surface of the light-shielding member face each other, the plate surface of the phase modulation mask having the curved surfaces, and the plate surface of the light-shielding member having the light-shielding films formed therein.