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:
Mar. 22, 2011
Filed:
Jul. 30, 2004
Mark J. Childs, Sutton, GB;
Alan G. Knapp, Crawley, GB;
David A. Fish, Haywards Heath, GB;
Nigel D. Young, Redhill, GB;
Mark J. Childs, Sutton, GB;
Alan G. Knapp, Crawley, GB;
David A. Fish, Haywards Heath, GB;
Nigel D. Young, Redhill, GB;
Koninklijke Philips Electronics N.V., Eindhoven, NL;
Abstract
The pixels of an active matrix display device have a current-driven light emitting display element, a drive transistor for driving a current through the display element, a storage capacitor for storing a pixel drive voltage to be used for addressing the drive transistor, a light-dependent device for detecting the brightness of the display element, and driver circuitry for providing data signals to the pixel external to the pixel array. This provides a pixel with optical feedback to compensate for display element ageing. The driver circuitry has a processing means for processing the feedback brightness signals and derives from them a threshold voltage for the drive transistor of the pixel as well as information relating to the performance of the display element, for ageing compensation.