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:
Jan. 30, 1996
Filed:
Oct. 27, 1994
Applicant:
Inventor:
Chi Wu, Crescent, CA;
Assignee:
Northern Telecom Limited, Quebec, CA;
Attorney:
Primary Examiner:
Int. Cl.
CPC ...
G02B / ; G02B / ;
U.S. Cl.
CPC ...
385 15 ; 385 11 ; 385 27 ; 385 28 ; 385 37 ; 385 40 ; 385122 ; 385131 ; 385132 ; 385141 ;
Abstract
A polarization independent wavelength tunable filter in the form of a dual-waveguide directional coupler. The conditions necessary to achieve coupling of a selected wavelength including both TE and TM polarization modes from one waveguide to a second waveguide in close proximity are achieved through a combination of geometrical and compositional tailoring of the waveguides and birefringence compensation in the waveguide and coupling layer.