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:
Apr. 29, 2008
Filed:
Nov. 25, 2004
Shinji Makimura, Kitakatsuragi-gun, JP;
Hiroshi Kido, Hirakata, JP;
Shingo Masumoto, Hirakata, JP;
Matsushita Electric Works, Ltd., Kadoma-shi, JP;
Abstract
Electrodeless discharge lamp lighting device. Start circuitsweeps operating frequency of resonance circuitfrom start frequency to end frequency of resonance frequency side through drive circuitand DC/AC conversion circuit, and starts electrodeless discharge lamp. Control circuitincreases or decreases variable power into circuitso that detection current comes to equal prescribed current for shifting the operating frequency to middle range frequency between the start frequency and the end frequency. The prescribed current is set so that the detection voltage in case of the middle range frequency becomes lower than that in case of the end frequency. Capacitorconstituting integration circuit starts suppression of operation of circuitwhen lampis started, and holds the suppression during at least start mode. Accordingly, it is possible to stably start lampand control stress on circuit(s) after lampis successfully started.