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. 02, 2012
Filed:
Nov. 17, 2006
John K. Roberts, Grand Rapids, MI (US);
Keith J. Vadas, Lake Worth, FL (US);
Chenhua You, Cary, NC (US);
John K. Roberts, Grand Rapids, MI (US);
Keith J. Vadas, Lake Worth, FL (US);
Chenhua You, Cary, NC (US);
Cree, Inc., Durham, NC (US);
Abstract
Methods of calibrating a lighting panel including a plurality of segments, each of said segments configured to emit a first color light and a second color light in response to pulse width modulation control signals having respective duty cycles include determining an average segment luminance for the lighting panel, determining a luminance variation of each segment to the average segment luminance, comparing the luminance variation of each segment to a threshold, and adjusting the duty cycle of at least one color of at least one segment to reduce the luminance variation in response to the luminance variation of a segment exceeding the threshold. Calibration systems are also disclosed.