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:
Dec. 26, 1995
Filed:
Aug. 29, 1994
Applicant:
Inventors:
David J DiGiovanni, Montclair, NJ (US);
Kenneth L Walker, New Providence, NJ (US);
Weyl-Kuo Wang, Westfield, NJ (US);
Raymond Wolfe, New Providence, NJ (US);
Assignee:
AT&T Corp., Murray Hill, NJ (US);
Attorney:
Primary Examiner:
Assistant Examiner:
Int. Cl.
CPC ...
G02B / ;
U.S. Cl.
CPC ...
385123 ; 385 11 ; 385-6 ; 3242441 ;
Abstract
In accordance with the invention, an optical fiber phase shifter comprises a length of asymmetrical optical fiber disposed perpendicular to a magnetic field for providing a non-reciprocal phase shift. Preferably the fiber is wound in a circular coil and exposed to an axial field as from a pancake magnet. In an isolator, the fiber length and magnet strength are chosen to provide non-reciprocal phase shifts of .+-.45.degree. or .+-.90.degree.. The isolator including the phase shifter can be any of several configurations.