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:
Aug. 13, 2002
Filed:
Jan. 30, 2001
David Butka, Tucson, AZ (US);
Brian Gerard Goodman, Tucson, AZ (US);
Michael Philip McIntosh, Tucson, AZ (US);
Raymond Yardy, Tucson, AZ (US);
International Business Machines Corporation, Armonk, NY (US);
Abstract
The detection threshold of an optical sensor is dynamically calibrated by measuring the maximum and minimum levels of the analog output produced by the sensor's light detector and setting the detection threshold of the sensor at an intermediate level between the two. The new detection threshold thus established is then used as the voltage reference that determines the logic state of the system. The invention may be implemented using analog-to-digital converter hardware already embedded in the system. Alternatively, the invention may be implemented using digital-to-analog converter hardware that may also be already present in the system.