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:
Feb. 11, 2003
Filed:
Dec. 06, 2000
Julian A. Fells, Epping, GB;
Richard Epworth, Herts, GB;
Nortel Networks Limited, Montreal, CA;
Abstract
Conventional quadratically chirped fiber Bragg gratings are typically apodized at both their high and low chirp ends. The present specification describes an improved Bragg grating reflector in which a second quadratically chirped region is arranged in front on the high chirp end of a substantially conventional quadratically chirped portion. The high chirp end of the first portion is not apodized; instead this apodization takes place in the second portion, and so enables the first portion to exhibit appreciable reflectivity to signals having wavelengths extending to the Bragg wavelength corresponding to the high chirp end of the first portion. The present invention thus enables the useable bandwidth of a quadratically chirped grating to be increased, and so enables an increased tuning range to be achieved in adjustable dispersion (and adjustable dispersion compensation) apparatus incorporating such gratings.