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. 13, 2001
Filed:
Apr. 20, 1998
Charles H. Anderson, Dallas, TX (US);
John B. Allen, Lucas, TX (US);
Texas Instruments Incorporated, Dallas, TX (US);
Abstract
An illumination system (,) having an automated calibration system (,) for adjusting the light intensity of individual elements (,) of an array of light emitting elements (,). An optical sensor (,) can be positioned in several locations (A,B,C) to sense incident light from a spatial light modulator (,) as the modulator is sequentially actuated one zone (,) at a time. The light output from each zone (,) of the spatial light modulator is characterized and compared to a golden standard, and the light emitting elements of the array associated with illuminating the zones that are deficient in light are ascertained. Adjustment circuitry (,) responsively adjusts and increases the drive current to the associated light emitting elements (,) that are deficient in light output. A look-up table is utilized to determine which LEDs (,) need adjustment to their drive currents to insure uniform illumination in the process and cross-process direction at an image plane. The present invention is ideally suitable for xerographic printers.