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. 18, 1999
Filed:
Mar. 17, 1997
Stephen G Grubb, Fremont, CA (US);
Raymond Zanoni, Fremont, CA (US);
Jean-Luc Archambault, Savage, MD (US);
SDL, Inc., San Jose, CA (US);
Abstract
A fiber laser uses a chirped Bragg grating as the output coupler and the grating is oriented so that the grating period increases in the direction towards the end of the cavity--the 'red' end of the grating is at the output coupling end of the cavity. This grating orientation unexpectedly produces a relatively large reduction in the noise generated by the fiber laser. In one embodiment, the chirped Bragg grating is produced by transversely doping spaced-apart portions of the longitudinal fiber core with elements that modify the refractive index of the core. The 'chirp' in the grating period is produced by modifying the period of the transversely doped fiber core portions during manufacture of the grating. In another embodiment, a partially reflective chirped fiber grating is used at the input side of the laser as well as at the output side. In yet another embodiment, the chirped grating is manufactured as an unchirped fiber grating where the period of the transversely-doped fiber core portions is constant and a chirp is introduced by selectively bending the fiber along its length, thereby producing a varying grating period.