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:
Oct. 21, 1997
Filed:
Aug. 05, 1996
Ravi Shanker Ananth, Ancaster, CA;
Sudhir Muniswamy Gowda, Ossining, NY (US);
Mark Samson Milshtein, Hillsboro, OR (US);
Mark B Ritter, Danbury, CT (US);
Dennis Lee Rogers, Croton-on-Hudson, NY (US);
International Business Machines Corporation, Armonk, NY (US);
Abstract
An automatic and adaptive threshold setting circuit for an IR receiver is capable of operating over a broad range of frequencies and power levels. The adaptive threshold circuit allows a very sensitive threshold in environments where little sunlight or other ambient light reaches the receiver, but which will increase the threshold of the receiver when large amounts of ambient light fall on the photo diode. The circuit senses the current flowing through the reverse biased IR photo detector due to ambient light levels. This current measurement is used to adjust the sensitivity of the receiver.