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:
May. 17, 2011
Filed:
Jun. 20, 2008
Tetsuji Hirao, Hyoto, JP;
Tetsuji Hirao, Hyoto, JP;
Ushio Denki Kabushiki Kaisha, Tokyo, JP;
Abstract
A discharge lamp lighting apparatus for turning on a discharge lamp has a lighting condition in which a projection is formed at a tip of an electrode for electric discharge. In the discharge lamp lighting apparatus, when the polarity-reversal mode is the second mode, the inverter control circuit operates to generate the inverter control signal so that a DC component contained in the output current increases more than that in the first mode, when the polarity-reversal mode is the first mode, and it is detected that the lamp voltage is lower than a predetermined first voltage, the polarity-reversal mode control circuit changes the polarity-reversal mode into the second mode, and when the polarity-reversal mode is the second mode, and it is detected that the lamp voltage is higher than a predetermined second voltage, the polarity-reversal mode control circuit changes the polarity-reversal mode into the first mode.