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:
Oct. 19, 1999
Filed:
Jun. 20, 1997
Lawrence James Pelz, Jr, Lenexa, KS (US);
Helin Ji, Lawrence, KS (US);
Xiaojun Fang, Lawrence, KS (US);
Christopher Thomas Allen, Independence, MO (US);
Kenneth Robert Demarest, Lawrence, KS (US);
Victor Samuel Frost, Lawrence, KS (US);
Sprint Communications Company L.P., Kansas City, MO (US);
Abstract
The invention is a method and apparatus that provides for the control of optical signals in a polarization-independent manner using birefringence. The invention includes an optical coupler connected to a birefringence element by an optical path loop. The optical coupler and optical path loop could be a Sagnac interferometer. The birefringence element affects the phase velocity of optical signals based on a control signal, and it can introduce a relative phase shift between optical signals propagating around the loop. The optical signals can be routed based on this phase shift.