Accession Number : ADD000326

Title :   Birefringence Read Bi4Ti3O2 Display and Memory Device.

Descriptive Note : Patent,

Corporate Author : DEPARTMENT OF THE AIR FORCE WASHINGTON D C

Personal Author(s) : Luke,Theodore E ; Cummins,Stewart E

Report Date : 10 Sep 1974

Pagination or Media Count : 14

Abstract : In the patent information to be stored is written into a single crystal of bismuth titanate, by either direct electrodes, photoconductors, or electron beams. Storage is by oppositely switched domains in the poled bismuth titanate crystal. The crystal is positioned between crossed polarizers, positioned 45 degrees from extinction, and rotated about the b axis such that an OFF state by thickness extinction occurs for one of the domains; the opposite domain then being in an ON state. Readout in one embodiment is by monochromatic light. In another embodiment a second bismuth titanate crystal is positioned adjacent the storage crystal and oriented such that its b axis is perpendicular to the b axis of the first crystal to provide a storage system that is read out with white light.

Descriptors :   *Memory devices, *Patents, Optical equipment, Display systems, Bismuth compounds, Titanates, Birefringence, Ferroelectric crystals

Subject Categories : Computer Hardware

Distribution Statement : APPROVED FOR PUBLIC RELEASE