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:
Aug. 28, 2001
Filed:
Sep. 11, 1997
Stephen B. Alexander, Millersville, MD (US);
Jean-Luc Archambault, Severna Park, MD (US);
Victor Mizrahi, Columbia, MD (US);
Henry H. Yaffe, Reisterstown, MD (US);
Ciena Corporation, Linthicum, MD (US);
Abstract
In accordance with the present invention, optical channels to be demultiplexed are supplied to first and second fibers via an optical splitter. Low loss interference filters, for example, coupled to the first and second optical fibers, select respective groups of channels. Each group of channels is next demultiplexed with sub-demultiplexers into individual channels, each of which is then sensed with a corresponding photodetector. Although the optical splitter introduces an optical power loss at the input to the demutiplexer, the interference filters and sub-demultiplexer create little additional loss. As a result, the total power loss associated with the present invention is significantly less than that obtained with a conventional n channel demultiplexer based on a 1×n splitter. Accordingly, large numbers of channels, e. g., in excess of forty can be readily demultiplexed and detected.