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:
Apr. 16, 2013
Filed:
Mar. 05, 2010
Marc Drader, Kitchener, CA;
James Robinson, Elmira, CA;
Jerry Mailloux, Waterloo, CA;
Robert Lowles, Waterloo, CA;
Marc Drader, Kitchener, CA;
James Robinson, Elmira, CA;
Jerry Mailloux, Waterloo, CA;
Robert Lowles, Waterloo, CA;
Research In Motion Limited, Waterloo, Ontario, CA;
Abstract
A field sequential liquid crystal display maintains its white color point through compensation values to at least one color light emitting diode that illuminates the display. The compensation values may be impedances to control the current or pulsing of the current source according to a pulse width modulation technique. A degradation curve may be used to calculate extrapolate the theoretical forward voltage of the light emitting diode. Additional complexity arises from the need for calculating uptime for multiple light emitting diodes of different colors. Brightness levels may also be factored in. Additional processing of a display element may be provided when a grey scale image is being generated.