Patent ID: 7804758

Claim:
A holographic information recording/reproducing apparatus comprising: a light source; a splitter unit that splits a light beam from the light source into a first light beam and a second light beam; a spatial light modulator that makes the first light beam bear information; a first galvano mirror that reflects the second light beam toward an information recording medium; a second galvano mirror that makes the second light beam coming out from the information recording medium reenter the information recording medium; and a controller that controls the angle of the first galvano mirror and that of the second galvano mirror, wherein the controller controls the first galvano mirror and the second galvano mirror so as to establish relationships of θ 1 ≠θ 2 and θ 1 =θ 3 , where θ 1 is the angle of incidence of the second light beam entering the information recording medium at the time of recording; θ 2 is the angle of incidence of the second light beam entering the information recording medium at the time of reproduction; and θ 3 is the angle of incidence of the second light beam reentering the information recording medium at the time of reproduction.