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:
Jul. 17, 2012
Filed:
Mar. 13, 2008
Satoru Nagata, Kobe, JP;
Jun Kumagai, Suita, JP;
Naoki Komatsu, Kobe, JP;
Panasonic Corporation, Osaka, JP;
Abstract
A discharge lamp lighting device includes: a direct current power supply circuit that outputs direct current power; an inverter circuit that converts the direct current power, which is outputted by the direct current power supply circuit, into alternating current power, and supplies the alternating current power to a discharge lamp; a control circuit that controls a frequency of an output of the inverter circuit (operation frequency); and a starting detection circuit that detects beginning (starting) of a discharge in the discharge lamp. The control circuit operates in a starting improvement mode, in which the operation frequency is lowered than an operation frequency in a lighting mode, during a predetermined time from when the starting of the discharge lamp is detected by the starting detection circuitduring a no-load mode. Thereafter, the control circuit shifts to the lighting mode in which lighting of the discharge lamp is maintained. In such a way, the discharge lamp can be smoothly shifted to stable lighting.