Enhanced nondestructive holographic reconstruction

• Main Authors: REDFIELD STEPHEN R, HESSELINK; LAMBERTUS
• Format: Patent
• Language: English
• Published: 04.09.1990
• Subjects: CINEMATOGRAPHY; COLOUR PRINTING; ELECTROGRAPHY; GENERAL TAGGING OF CROSS-SECTIONAL TECHNOLOGIES SPANNING OVER SEVERAL SECTIONS OF THE IPC; GENERAL TAGGING OF NEW TECHNOLOGICAL DEVELOPMENTS; HOLOGRAPHIC PROCESSES OR APPARATUS; HOLOGRAPHY; LINING MACHINES; PERFORMING OPERATIONS; PHOTOGRAPHY; PHYSICS; PRINTING; PRINTING, DUPLICATING, MARKING, OR COPYING PROCESSES; STAMPS; TECHNICAL SUBJECTS COVERED BY FORMER USPC; TECHNICAL SUBJECTS COVERED BY FORMER USPC CROSS-REFERENCE ART COLLECTIONS [XRACs] AND DIGESTS; TECHNICAL SUBJECTS COVERED BY FORMER USPC CROSS-REFERENCE ARTCOLLECTIONS [XRACs] AND DIGESTS; TRANSPORTING; TYPEWRITERS

A method for promoting enhanced nondestructive reconstruction of holograms recorded in photorefractive media involves control of the polarization states of the reconstruction beam and the recording beams, control of the cummulative recording energy, and use of a relatively high external field applied across the media 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, the recording geometry, and the applied voltage during reconstruction and recording, and various other parameters. In general, the reconstruction efficiency starts at a relatively high level, initially reduces, and then subsequently grows above the starting value, and can be made substantially nondestructive over a typical reconstruction cycle, with erasure times exceeding forty-five minutes.