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. 19, 2011
Filed:
Nov. 21, 2007
Hideo Sato, Hitachi, JP;
Teruaki Saito, Mobara, JP;
Shigeyuki Nishitani, Mobara, JP;
Hitachi Displays, Ltd., Chiba, JP;
Abstract
The present invention provides a display device having an illuminance detection circuit. The illuminance detection circuit includes: a photosensor which changes an optical current in response to illuminance of an external light; a capacitor which discharges a charge when the optical current flows in the photosensor; a comparator which compares a voltage at one end of the capacitor and a comparison reference voltage; a switching circuit which is connected to one end of the capacitor and charges the capacitor in response to a level of an output signal of the comparator; and a selection circuit which applies either a first voltage or a second voltage to the other end of the capacitor in response to the level of the output signal of the comparator.
Data source: USPTO (United States Patent and Trademark Office) public patent records. Weekly synchronization. How IDiyas builds this profile