Patent ID: 8699310
Filing Date: 2014-04-15
Classification: G03H,G11B

Abstract:
1. An optical information recording medium configured to use holography to record and reproduce information, the optical information recording medium comprising: a recording layer configured to store an interference pattern produced when a signal beam and a reference beam are superimposed, the interference pattern recorded as a change of a refractive index at the time of recording of information; and a reflection layer including a reflecting diffraction grating, and configured to produce a phase conjugate beam of the reference beam at the time of reproduction of the information, the phase conjugate beam of the reference beam traveling in the opposite direction to the reference beam while holding the same wavefront as the reference beam; wherein the phase conjugate beam of the reference beam is diffracted by the interference pattern to produce reproduction light, which is a first (1 wherein a reflectance of the optical information recording medium is higher at the time of reproduction of the information as compared with at the time of recording of the information.