Optical add-drop multiplexer having an interferometer structure
US6351581B1 · kind B1 · utility
Assignee
Inventors
Key dates
| Filing date | Mar 17, 1998 |
| Grant date | Feb 26, 2002 |
| Priority date | — |
| Expiry date | Mar 17, 2018 |
Classification
- Technology area (CPC G)Physics
- CPC primaryG02B6/12026
- WIPO fieldOptics
- WIPO sectorInstruments
Abstract
An optical add-drop multiplexer (ADM) 60 avoids waveguide crossings by being constructed in the form of a Mach-Zehnder interferometer having a demultiplexer/multiplexer (demux/mux) pair 300, 400 in each of its arms. Each demux/mux pair is interconnected by coherent connecting paths 70, 80 having heating elements 65, 66 for increasing the path length of selected connecting paths. Waveguide optical couplers 61, 62 having asymmetric transfer functions are used at the input and output of the ADM. These couplers cooperate with the activated heating elements to add and/or delete a selected optical channel to/from an optical transmission path. Each coherent connecting path includes a number of waveguides. The end-to-end transmission characteristic of the ADM through each individual waveguide has a Gaussian shape. These Gaussian shapes are designed intersect at their −3 dB wavelengths so that the end-to-end transmission characteristic of the ADM is flat.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.