The patent badge is an abbreviated version of the USPTO patent document. The patent badge does contain a link to the full patent document.
The patent badge is an abbreviated version of the USPTO patent document. The patent badge covers the following: Patent number, Date patent was issued, Date patent was filed, Title of the patent, Applicant, Inventor, Assignee, Attorney firm, Primary examiner, Assistant examiner, CPCs, and Abstract. The patent badge does contain a link to the full patent document (in Adobe Acrobat format, aka pdf). To download or print any patent click here.
Patent No.:
Date of Patent:
Mar. 23, 1976
Filed:
Apr. 15, 1974
Marvin D Drake, Palm Bay, FL (US);
Harris-Intertype Corporation, Cleveland, OH (US);
Abstract
An electro-optical transducer and data storage device is operated by electrically establishing different electric field levels in a retentive ferroelectric PLZT crystal. The crystal may have a plurality of areas that serve as data storage elements, each of which is defined by crossover areas of rows and columns of transparent electrodes that are on opposite sides of the crystal, each storage element being spaced away from other storage elements of the crystal by surrounding edge regions. When a data storage element is retentively polarized by the application and removal of a voltage pulse to opposite electrodes, the portion of the crystal between the electrodes contracts transversely, establishing a strain gradient in the edge regions surrounding the data storage element. This localized strain gradient, together with a fringing electric field in the edge regions, causes a high level of birefringence there, and permits the edge regions to serve as amplitude modulators of polarized light. When light is applied on a path through a polarizer, through the crystal, and through a cross-polarized analyzer, the output of the analyzer has light from edge regions of elements which have not been polarized. The apparatus can serve as an electro-optical transducer and memory for large blocks of data, for example.