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. 10, 2012
Filed:
Dec. 17, 2009
Kentaro Yamauchi, Ashiya, JP;
Takeshi Takezawa, Matsumoto, JP;
Tetsuo Terashima, Chino, JP;
Shigeyasu Soma, Muroran, JP;
Kentaro Yamauchi, Ashiya, JP;
Takeshi Takezawa, Matsumoto, JP;
Tetsuo Terashima, Chino, JP;
Shigeyasu Soma, Muroran, JP;
Seiko Epson Corporation, Tokyo, JP;
Abstract
A light source device includes: a discharge lamp provided with two electrodes; a discharge lamp lighting section adapted to light the discharge lamp by supplying the discharge lamp with electrical power while alternately switching a polarity of one of the electrodes of the discharge lamp with respect to the other of the electrodes; and a time-division color separation section adapted to receive light emitted from the discharge lamp in a lighted state and sequentially emit light beams with colors different from each other, wherein the discharge lamp lighting section switches the polarity in sync with a change in the color of the light beam emitted from the time-division color separation section, and provides, as retentive periods in which a duty ratio, which is a ratio of a positive polarity period with the polarity kept positive to a period of the polarity switching, is retained at a constant value over a predetermined period of time, a first retentive period and a second retentive period different in the duty ratio from the first retentive period, thereby modulating the duty ratio.