Hologram refresh method to be applied to holographic memory devices and the device

摘要

PROBLEM TO BE SOLVED: To provide a hologram memory device which can raise a storage density even when increasing the number of hologram capable of multiple storage and has a simple device constitution.;SOLUTION: Signal beams 5 are inputted into a first photorefractive medium 1 while changing spatial phase information of the signal beams by means of a spatial light modulator 17, reference beams 6 for interference of the signal beams are inputted from a direction intersecting with the signal beams 5 and the hologram is multiply recorded on the first photorefractive medium 1 according to the interference between the reference beams 6 and the signal beams 5. Thereafter, the signal beams 5 are made into non-input state, the reference beams 6 are inputted into the first photorefractive medium 1 to form multiple diffractive beams 7 of the hologram, the multiple diffractive beams 7 are inputted into a second photorefractive medium 2 to generate phase conjugate beams 8 of the multiple diffractive beams 7, the phase conjugate beams 8 are inputted into the first photorefractive medium 1 and, thereby, the hologram is collectively re-recorded.;COPYRIGHT: (C)2007,JPO&INPIT