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:
Sep. 09, 2014
Filed:
Apr. 18, 2012
Ikuo Takanashi, Soka, JP;
Ikuo Takanashi, Soka, JP;
Canon Kabushiki Kaisha, Tokyo, JP;
Abstract
A first current amount which has been preset so that the light amount of an LED element reaches a target light amount value at a predetermined reference ambient temperature, and a thermal correction coefficient for correcting the first current amount so that the light amount of the element reaches the target light amount value at an ambient temperature different from the reference ambient temperature are stored. Furthermore, when the light amount of the LED element reaches the target light amount value, an aging correction coefficient for correcting the first current amount to correct aging at the reference ambient temperature is calculated from a second current amount supplied to the LED element and the thermal correction coefficient corresponding to the ambient temperature of the LED element, and is then stored.