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. 15, 1994
Filed:
Apr. 08, 1992
Applicant:
Inventors:
Alexander J Robertson, Dunmow, GB;
Stephen Day, Harlow, GB;
Assignee:
Northern Telecom Limited, Montreal, CA;
Primary Examiner:
Int. Cl.
CPC ...
G02B / ; G01B / ;
U.S. Cl.
CPC ...
359260 ; 356352 ; 359499 ; 359578 ; 385 11 ;
Abstract
Simple polarization independent wavelength tuning components (filters) employ a filter element, such as a Fabry-Perot etalon element, which is such that light input thereto undergoes two element transitions with orthogonal polarization states before being output, in order to suppress polarization noise. The element may be mounted for rotation about a single axis. In one arrangement, two etalon filters (20, 21), are separated by a half wave plate (22) providing the necessary polarization rotation. The two etalon filters and the half wave plate comprise a single element rotatable about the single axis.