Patent ID: 6707585
Filing Date: 2004-03-16
Classification: G03H,G11B

Abstract:
A holographic recording and reproducing apparatus for recording data on a recording medium and reproducing data from the recording medium, the recording medium being made of a photorefractive material, said apparatus comprising:a support portion for detachably supporting the recording medium; a recording-reference-light-beam-supplying-portion for supplying a coherent recording reference light beam having a first wavelength and propagating along a recording optical axis to a major surface of said recording medium; a signal-light-beam-supplying-portion including a converging lens for converging a coherent signal light beam having the first wavelength which is modulated in accordance with image data, in an optical path into the recording medium such that said signal light beam intersects with the recording reference light beam to produce an optical interference pattern of refractive index with said reference and signal light beams within said recording medium; a reproducing-reference-light-beam-supplying-portion for supplying into the recording medium a coherent reproducing reference light beam having the first wavelength and propagating in an opposite direction along said recording optical axis of the recording reference light beam to generate a phase conjugate wave from a refractive-index grating of the optical interference pattern; a photo-detecting portion including a receiving lens for receiving said phase conjugate wave and a photo-detector for detecting the dot pattern imaged with said phase conjugate wave to reproduce the image data; and a light transferring portion for making a common image-formation plane to said receiving lens and said converging lens to transfer said phase conjugate wave received from said receiving lens to said converging lens in such a manner that said receiving lens reconstructs a real image of the image data on the common image-formation plane, and during the irradiation of the recording reference light beam, forwarding a reproduced light from the real image through said converging lens to converge it into the recording medium in such a manner that said reproduced light intersects with the recording reference light beam to produce another optical interference pattern of refractive index in said recording medium.