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. 10, 2013
Filed:
Oct. 24, 2012
Applicant:
Hitachi, Ltd., Tokyo, JP;
Inventors:
Masaki Mukoh, Fuchu, JP;
Harukazu Miyamoto, Higashimurayama, JP;
Assignee:
Hitachi, Ltd., Tokyo, JP;
Primary Examiner:
Assistant Examiner:
Int. Cl.
CPC ...
G11B 5/455 (2006.01);
U.S. Cl.
CPC ...
Abstract
The wavelength is monitored using a spectrum analyzer in a state where a semiconductor laser is being driven while changing the light-emitting time of the semiconductor laser. When the internal temperature of the semiconductor laser estimated from a measured wavelength falls out of a preset temperature range, a gimbal assembly is identified as a defective product.