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:
Apr. 18, 1995
Filed:
Apr. 05, 1994
Applicant:
Inventors:
Alan Fielding, Bishop's Stortford, GB;
Christopher Chew, Bishop's Stortford, GB;
Vernon Baker, Harlow, GB;
Sandra Davis, Ware, GB;
Assignee:
Northern Telecom Limited, Montreal, CA;
Primary Examiner:
Assistant Examiner:
Int. Cl.
CPC ...
G02B / ;
U.S. Cl.
CPC ...
385 43 ; 385 15 ; 385 11 ; 385 48 ; 385 96 ; 65501 ; 65438 ;
Abstract
In the manufacture of a wavelength multiplexing 2.times.2 tapered fused fiber coupler by progressive stretching, the birefringence of the coupler resulting from the progressive stretching is subsequently nulled-out by elastic twisting of the coupler. The progressive stretching is performed, under temperature conditions providing a profile in the coupling region of the coupler having the property that the coupling strength for one of the principal polarization planes of the coupler remains substantially constant during said elastic twisting.