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:
Nov. 12, 2002
Filed:
Dec. 28, 2000
Paul A Firth, Stoke Gabriel, GB;
Adrian Janssen, Exeter, GB;
Nortel Networks Limited, St. Laurent, CA;
Abstract
It is known to couple a collimated beam of light into the end of an optical fibre with a graded index lens having an angled facet at the lens/fibre interface to reduce the amplitude of Fresnel retroreflected power. The expense incurred in providing angled facets is avoided by using a two-part compound lens. One part is a graded index lens part having an axial length shorter than a quarter period. To this is bonded a cylindrical uniform refractive index lens part whose index is matched with the effective refractive index of the fibre. This reduces the amplitude of the retroreflection power by causing the displacement of the Fresnel reflection from the lens focus.