Patent ID: 7085026

Claim:
An optical information recording apparatus for recording information in an optical information recording medium having reflecting layer and information recording layer in which information is recorded utilizing holography, the apparatus comprising: a pick-up device provided in a face-to-face relationship with the optical information recording medium, the pick-up device comprising: a light source; an information light generation means for generating information light carrying two dimensional digital pattern information using the beams of light emitted by the light source; a recording reference light generation means including modulation means for spatially modulating the beams of light emitted by the light source, for generating reference light for recording being spatially modulated by the modulation means; and a recording optical system including only one objective lens for projecting the information light generated by the information light generation means and the reference light for recording generated by the recording reference light generation means upon the optical information recording medium, for illuminating the information recording layer on the same side thereof with the information light and the reference light for recording such that the information is recorded in the information recording layer in the form of an interference pattern as a result of using the reflecting layer as a reference plane to generate interference between the information light and the reference light for recording, wherein the recording optical system projects the information light and the reference light for recording such that an optical axis of the information light and an optical axis of the reference light for recording are located on a same line.