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:
Feb. 08, 1994
Filed:
Jun. 17, 1991
Alastair D McAulay, Centerville, OH (US);
Wright State University, Dayton, OH (US);
Abstract
A method and apparatus operate an optical memory to perform bit-slice associative memory operations by storing a plurality of keywords to define a keyword database and accessing the database by means of one of the keywords. Preferably, the plurality of keywords are unique and are used to retrieve data which corresponds individually to the keywords. Operation of the memory is by identification of a keyword, the location of which is to be determined within the memory, for example for data retrieval. The identified keyword is then used effectively as a retrieval mask to access the plurality of keywords. The keyword database and its complement are stored in an optical device with the keyword to be retrieved and its complement being stored in recall optical devices. The keyword database or its complement is repetitively swept by shifting output columnar vectors by one bit position until all bit positions have been swept. Only identical keywords stored in the memory will result in light output during the last sweep with the light output identifying the row or rows which contain the keyword to be retrieved. The optical paths can be reduced and/or the use of complements can be eliminated by means of dual-rail coding and polarization techniques.