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. 27, 2001
Filed:
Oct. 30, 1998
Thomas C. Smelker, Venice, FL (US);
Baker Electronics, Inc., Sarasota, FL (US);
Abstract
In order to extend the life of a light source such as a CCFL or the like being used in backlighting system for an LCD, the present invention includes an optical sensing circuit, an amplification circuit, an averaging circuit, a comparator circuit, a controller, and an inverter dimmer circuit. The initial power applied to the light source is limited to a value which is less than its maximum rate power thus reducing the rate of light source degradation geometrically. The brightness of the light source is monitored using a photosensitive element/sensor, and as the brightness reduces with the passing of time, the power that is supplied to the light source is gradually increased. This both prolongs the life of the life source and obviates any perceivable reduction in display brightness.