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:
Jun. 14, 2011
Filed:
Dec. 11, 2009
Tomoyoshi Arimoto, Hyogo, JP;
Takashi Yamashita, Hyogo, JP;
Tetsuji Hirao, Hyogo, JP;
Tetsu Okamoto, Hyogo, JP;
Kentaro Fujita, Hyogo, JP;
Tomoyoshi Arimoto, Hyogo, JP;
Takashi Yamashita, Hyogo, JP;
Tetsuji Hirao, Hyogo, JP;
Tetsu Okamoto, Hyogo, JP;
Kentaro Fujita, Hyogo, JP;
Ushio Denki Kabushiki Kaisha, Tokyo, JP;
Abstract
A discharge lamp lighting apparatus includes a discharge container, a pair of electrodes and a power supply apparatus. An alternating current of a frequency, which is lower than stationary frequency, is inserted periodically into the alternating current of stationary frequency. When a lighting current value of the discharge lamp is smaller than a predetermined lower limit, the frequency is set as predetermined minimum frequency. When the lighting current value of a discharge lamp is larger than a predetermined maximum value, the frequency is set as predetermined maximum frequency. When a lighting current value of the discharge lamp is between the lower limit and the maximum value, the frequency is set as a selected frequency corresponding to the lighting current value. The selected frequency increases according to an increase of frequency change as a lighting current value increases.