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. 12, 2002
Filed:
Oct. 02, 2000
Iain M. Hunter, Brighton, GB;
U.S. Philips Corporation, New York, NY (US);
Abstract
In an active matrix electroluminescent display device the drive current through an EL display element ( ) in each pixel ( ) in a drive period is controlled by a driving device ( ) based on a drive signal applied to the pixel in preceding address period and stored as a voltage on an associated storage capacitor ( ). In order to counteract the effects of display element ageing through which the light output of an element for a given drive signal level diminishes over time, the pixel includes a feedback circuit ( ) which is responsive to the potential difference across the display element in an initial part of the drive period indicative of the extent of ageing and which is arranged to adjust the voltage stored on the storage capacitance accordingly.