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:
May. 01, 2012
Filed:
Mar. 05, 2009
Masataka Nakazawa, Miyagi, JP;
Akihito Suzuki, Kyoto, JP;
Toshihiko Hirooka, Miyagi, JP;
Masato Yoshida, Miyagi, JP;
Kazunori Shiota, Miyagi, JP;
Masataka Nakazawa, Miyagi, JP;
Akihito Suzuki, Kyoto, JP;
Toshihiko Hirooka, Miyagi, JP;
Masato Yoshida, Miyagi, JP;
Kazunori Shiota, Miyagi, JP;
Other;
Advantest Corporation, Tokyo, JP;
Abstract
Provided is a laser apparatus including: a DFB fiber laserincluding, as an amplitude medium, a rare earth doped silica optical fiber codoped with a high concentration of aluminum; an optical feedback pathformed by a ring-shaped optical fiber; and an optical couplera) feeding back a part of an output of the DFB fiber laserto the DFB fiber laservia the optical feedback path, and b) outputting, to outside, another part of the output of the DFB fiber laser, where the optical fiber forming the optical feedback pathis longer than a length at which a relaxation oscillation noise in the output to the outside becomes −110 dB/Hz.