公开(公告)号：EP0407396A4

公开(公告)日：1992-06-03

申请号：EP89902214

申请日：1988-12-29

Applicant: MICROELECTRONICS AND COMPUTER TECHNOLOGY CORPORATION

Inventor： REDFIELD, STEPHEN, R. ,  HESSELINK, LAMBERTUS

IPC: B41M5/26 ,  G03H1/02 ,  G03H1/04

CPC classification number: G03H1/0248 ,  Y10S359/90

Abstract: A method for promoting enhanced nondestructive reconstruction of holograms recorded in photorefractive media (10) involves control of the polarization states of the reconstruction beam (24) and the recording beams (24, 26), control of the cumulative recording energy, and use of a relatively high external field applied across the media (10) during recording which is subsequently reduced during reconstruction. The resulting reconstruction history characteristics are selectively tailored by adjusting the polarization and intensity of the reconstruction beam (24), the recording geometry, and the applied voltage (40) during reconstruction and recording, and various other parameters. In general, the reconstruction efficiency (48) starts at a relatively high level, initially reduces, and then subsequently grows above the starting values, and can be made substantially nondestructive over a typical reconstruction cycle, with erasure times exceeding forty-five minutes.

公开(公告)号：EP0349634A4

公开(公告)日：1991-11-13

申请号：EP89901657

申请日：1988-12-27

Applicant: MICROELECTRONICS AND COMPUTER TECHNOLOGY CORPORATION

Inventor： HESSELINK, LAMBERTUS ,  REDFIELD, STEVE, R.

IPC: G02F1/055 ,  G02F1/05 ,  G03H1/02 ,  G03H1/04 ,  G03H1/26 ,  G06E3/00 ,  G11C13/04

CPC classification number: G03H1/0248 ,  G02F1/0541 ,  G03H1/26 ,  G03H2001/0066 ,  G03H2001/026 ,  G03H2260/30 ,  G03H2260/54 ,  G06E3/005 ,  G11C13/044 ,  G11C13/046

Abstract: A photorefractive crystallyte array (10) for image recording and signal processing is disclosed. The photorefractive crystallytes (11) are configured as a two-dimensional array (10) of selected position and spacing designed, for example, to coincide with the spatial frequency components of an associated optical image, such as a Fourier transform image, and to permit optical signal processing.