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:
Feb. 23, 2010
Filed:
Jul. 11, 2006
Masaru Ikeda, Osaka, JP;
Syunsuke Ono, Osaka, JP;
Minoru Ozasa, Kyoto, JP;
Masahiro Yamamoto, Osaka, JP;
Go Yamada, Osaka, JP;
Masaru Ikeda, Osaka, JP;
Syunsuke Ono, Osaka, JP;
Minoru Ozasa, Kyoto, JP;
Masahiro Yamamoto, Osaka, JP;
Go Yamada, Osaka, JP;
Panasonic Corporation, Osaka, JP;
Abstract
Provided is a method for lighting a high pressure discharge lamp capable of increasing the life thereof. The lighting method is as follows. When the time elapse after lighting up the discharge lamp is within a predetermined condition (e.g. 5 minutes or less), constant current control is performed if the lamp voltage is lower than switching voltage (here, a first voltage value V) and constant power control is performed to maintain the lamp power at a power value Wif the lamp voltage is equal to or above the switching voltage. After the predetermined condition (5 minutes) is exceeded, the constant power control is performed by lowering the value of the switching voltage from the first voltage value Vto the second voltage value V. If the lamp voltage is equal to or above the switching voltage lowered, the lamp power is maintained at power value W