Patent ID: 8208186

Claim:
An optical reproducing apparatus comprising: a light source that irradiates a coherent light; a spatial light modulator that includes a plurality of pixel portions arranged in a two-dimensional shape, includes a signal light region generating a signal light or a direct-current component to be applied and a reference light region arranged so as to surround the signal light region and generating a reference light coaxial with the signal light, displays a transmission pattern having a constant brightness in the signal light region of the spatial light modulator and displays a reference light pattern in the reference light region of the spatial light modulator, modulates the light incoming from the light source per pixel according to a display pattern and generates the reference light and the direct-current component to be applied; a combined light optical system that condenses the reference light and the direct-current component to be applied generated by the spatial light modulator to a recording region of an optical recording medium, generates a diffracted light, which is a polarized light including a first polarization component with a first polarization plane and a second polarization component with a second polarization plane that is orthogonal to the first polarization plane, from a hologram recorded in the recording region, generates a direct-current component formed by a polarized light having a third polarization component with the first polarization plane having a polarizing direction orthogonal to the diffracted light and having the same phase as the phase of the diffracted light and a fourth polarization component with the second polarization plane having an opposite phase to the phase of the diffracted light, combines the direct-current component formed by the polarized light with the diffracted light and generates a combined light; a polarization beam splitter that separates the combined light generated by the combined light optical system into a fifth polarization component, which includes the first polarization component and the third polarization component, and a sixth polarization component, which includes the second polarization component and the fourth polarization component; a first light detector that detects a first reproduced image from the separated fifth polarization component; and a second light detector that detects a second reproduced image from the separated sixth polarization light component.