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:
Jun. 20, 2000
Filed:
Dec. 04, 1997
Applicant:
Inventor:
Tadayuki Iwano, Tokyo, JP;
Assignee:
NEC Corporation, Tokyo, JP;
Attorney:
Primary Examiner:
Assistant Examiner:
Int. Cl.
CPC ...
H04B / ; H04B / ;
U.S. Cl.
CPC ...
359124 ; 359110 ; 359180 ; 359182 ; 359187 ;
Abstract
An optical transmitter system includes a semiconductor laser, an external modulator, a detector and a frequency-modulation controller. The semiconductor laser transmits an optical signal of a predetermined wavelength onto an optical fiber and a backscattering wave caused by the optical signal is detected by the detector. The frequency-modulation controller controls the semiconductor laser so that the amplitude of a frequency-modulation signal applied to the semiconductor laser is varied depending on a detection signal of the backscattering wave.