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:
Mar. 26, 1996
Filed:
Aug. 18, 1994
Applicant:
Inventor:
Chi Wu, Nepean, CA;
Assignee:
Northern Telecom Limited, Montreal, CA;
Attorney:
Primary Examiner:
Assistant Examiner:
Int. Cl.
CPC ...
G02B / ;
U.S. Cl.
CPC ...
385 42 ; 385 24 ; 385 41 ; 385 46 ;
Abstract
A polarization independent tunable filter/receiver for optical communications. The tunable filter, operating as a directional coupler, has three waveguides including a central, feedguide and a pair of branch waveguides. Through either electro-optic effects or free carrier injection, the TM and TE polarization modes of the central wavelength can be coupled from the feedguide to the appropriate branch guide. The separated modes can be either detected independently or reunited in phase for further processing.