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:
Feb. 05, 2019
Filed:
Oct. 31, 2017
Seiko Epson Corporation, Tokyo, JP;
Satoshi Kito, Chino, JP;
Shun Sato, Matsumoto, JP;
SEIKO EPSON CORPORATION, Tokyo, JP;
Abstract
A discharge lamp driver includes a discharge lamp drive unit, a control unit, and a voltage detection part. When an inter-electrode voltage is smaller than a first predetermined value, the control unit controls the discharge lamp drive unit to provide a mixed period in which a first period and a second period are alternately repeated and a third period alternately including a first direct-current period and a second direct-current period. A length of the first direct-current period is larger than a length of the second direct-current period. The length of the second direct-current period is smaller than 0.5 ms. A total of the lengths of the first direct-current periods in the third period is larger than a length of the second period. When the inter-electrode voltage is smaller than the first predetermined value, the control unit is configured to increase the length of the third period in a stepwise manner.