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:
Sep. 15, 2015
Filed:
Nov. 01, 2011
Koji Yamada, Himeji, JP;
Keiichi Matsumoto, Himeji, JP;
Takashi Yamashita, Himeji, JP;
Takanori Samejima, Himeji, JP;
Koji Yamada, Himeji, JP;
Keiichi Matsumoto, Himeji, JP;
Takashi Yamashita, Himeji, JP;
Takanori Samejima, Himeji, JP;
Ushio Denki Kabushiki Kaisha, Tokyo, JP;
Abstract
A discharge lamp lighting device having a discharge lamp which has a pair of tungsten-made electrodes each having a protrusion formed at the tip thereof and an electric power feeding device which feeds an alternate current electric power to the discharge lamp, and is characterized in that the power feeding device has a function of switching between a first lighting mode in which a rated electric power is fed to the discharge lamp and a second lighting mode in which a lower electric power than the rated electric power is fed to the discharge lamp to light the discharge lamp, and therefore, can control electric power to be fed to the discharge lamp under such conditions that the average electric power change rate becomes 0.01-2.1 W/s during a mode switching period in which the switching from the first lighting mode into the second lighting mode is carried out.