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:
Jul. 20, 1999
Filed:
Aug. 30, 1996
Yuan P Li, Duluth, GA (US);
Lucent Technologies Inc., Murray Hill, NJ (US);
Abstract
An optical multiplexer/demultiplexer 500 comprises first and second star couplers 41, 42 that are interconnected by a number of optical waveguides 430 of unequal length (i.e., a grating). The multiplexer/demultiplexer functions to distribute optical signals in a first-wavelength region .lambda..sub.A (around 1550 nm) from one input port 401 of the first star coupler 41 to individual output ports 426 of the second star coupler 42 according to wavelength. The first star coupler includes at least one other input port 402 for receiving optical signals in a second wavelength region .lambda..sub.B (around 1310 nm) to be broadcast to all output ports of the second star coupler. In order to properly broadcast the optical signals in the second wavelength region, a power splitter 50 is connected in series with the other input port(s) of the first star coupler. The combined width w.sub.1 of the output port(s) of the power splitter is greater than the width w.sub.2 subtended by the central Brillouin zone of the multiplexer/demultiplexer. In one embodiment of the invention, the power splitter comprises a star coupler 50-1 having one input port 51 and many output ports; while in another embodiment, the power splitter comprises a tapered waveguide 50-2. A particularly useful device 100 is formed by adding a coarse WDM (80) to route optical input signals in the .lambda..sub.A wavelength region to the one input port of the first star coupler, and to route optical signals in the .lambda..sub.B wavelength region to the power splitter.