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:
Dec. 05, 1995
Filed:
Dec. 27, 1993
Girmay K Girmay, La Mirada, CA (US);
Xerox Corporation, Stamford, CT (US);
Abstract
A look ahead circuit for enabling the calibration of a ROS laser to be calibrated during the active part of the scan. A register takes a number of pixels from the stream of video and compares them to a plurality of possible matching pixel patterns. If a match is found, the pixel pattern is applied to a table look up to produce a digital representation of the laser power that should be produced as a result of these pixels, and this representation is converted in a digital to analog converter to an analog voltage which corresponds to the laser power that the laser should be putting out when generating this set of pixels. During the time when these pixels are being printed, a detector measures the laser power and that is compared to the analog voltage to produce a difference. At the same time, a capture circuit, as the result of finding the match, turns on a sample and hold circuit which couples out the difference as the error output, which is used to correct the laser output.