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. 24, 2007
Filed:
Sep. 30, 2003
Kazuhiro Ishiguchi, Kikuchi-gun, JP;
Kazuhiro Ishiguchi, Kikuchi-gun, JP;
Advanced Display Inc., Kumamoto, JP;
Abstract
A light source unit includes a light source having LED chips for emitting different colors of light and an optical sensor for detecting light from a light mixer. A light source control section controls by feedback control luminance of each of the LED chips according to values detected by the optical sensor. The light source unit also includes a temperature control section for controlling the temperature of the light source. The temperature control section is a feedback control system. Keeping the light source at a constant temperature allows suppressing spectrum changes of the LED chips with temperature, thereby suppressing changes in the luminance and chromaticity of the light source unit.