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:
Aug. 04, 1992
Filed:
Jun. 21, 1990
Applicant:
Inventors:
Shinya Inagaki, Tokyo, JP;
Masayoshi Shigihara, Tokyo, JP;
Sakae Yoshizawa, Tokyo, JP;
Kazuya Sasaki, Mitaka, JP;
Keiko Takeda, Yokohama, JP;
Assignee:
Fujitsu Limited, Kawasaki, JP;
Attorney:
Primary Examiner:
Int. Cl.
CPC ...
H01S / ; H01S / ; G02B / ;
U.S. Cl.
CPC ...
359341 ; 359345 ; 372-6 ;
Abstract
An optical fiber amplifier is disclosed wherein pumping light and signal light are introduced into an optical fiber doped with a rare-earth element to directly amplify the signal light. The optical fiber amplifier of the invention comprises means constituted from a reflecting film, a fiber loop or the like for causing pumping light to pass by a plurality of times in the doped fiber. Due to the provision of the reflective film or the fiber loop, pumping light can be utilized efficiently, and the amplification factor of the optical fiber amplifier is improved.