HOLOGRAPHIC MEMORY DEVICE AND REPRODUCTION/RECORDING METHOD

摘要

An optical beam with the same amplitude distribution and phase distribution as those of the signal beam used for recording is radiated to the hologram recording medium via an optical system of the signal beam prior to reproduction so that the optical beam with the amplitude and phase of the reference beam upon recording is generated through diffraction. A wavefront sensor detects the wavefront configuration of the diffraction beam and obtains preliminarily the suitable wavefront of the reference beam for reproduction. The wavefront control element preliminarily corrects the wavefront of the reference beam to an optimum wavefront.