Optoelectronic memories with photoconductive thin films

Patent 5327373 Issued on July 5, 1994. Estimated Expiration Date:

August 21, 2012. Estimated Expiration Date is calculated based on simple USPTO term provisions. It does not account for terminal disclaimers, term adjustments, failure to pay maintenance fees, or other factors which might affect the term of a patent.

Abstract Claims Description Full Text

Patent References

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Inventors

Assignee

Board of Regents, The University of Texas System

Application

No. 933452 filed on 08/21/1992

US Classes:

365/112, Photoconductive365/109, Photoconductive and ferroelectric365/110, Electroluminescent and photoconductive365/113, Amorphous365/119Color centers

Examiners

Primary: LaRoche, Eugene R.
Assistant: Hoang, Huan

Attorney, Agent or Firm

Arnold, White & Durkee

International Class

G11C 011/42

Abstract

Methods and apparatii are described for information storage in photoconductive film of single layer composition by irradiation of memory elements simultaneously with application of an electric field. Information is stored as trapped charge accumulations in the film when the irradiation is removed, but trapped charge can be released by subsequent irradiation. Repeated information storage, followed by erasure, returns the films to their original state without degradation.

Other References

Search Report (PCT/US93/07821), dated Nov. 8, 1993
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