Patent ID: 7636185

Claim:
A hologram recorder for recording a hologram in a hologram recording medium by interference of a recording beam with a reference beam, the recording beam being irradiated at a predetermined incident angle to the hologram recording medium via a spatial light modulator in a state that the recording beam is inclined in a predetermined direction, the reference beam being irradiated in a state that the reference beam is inclined in an opposite direction to the recording beam so that the reference beam crosses with the recording beam at a predetermined crossing angle, the hologram recorder comprising: a beam modulator for converting a Gaussian-beam having an intensity distribution of a Gaussian-distribution into a parallel beam having an intensity distribution tending to be uniform and allowing the parallel beam to travel to the spatial light modulator as the recording beam, wherein the Gaussian-beam has a center axis decentered from an optical axis of the beam modulator in a decentering direction including a directional component of the predetermined direction in which the recording beam is inclined or an opposite directional component to the predetermined direction.