Distributed amplification for lightwave transmission system
CA 2024352 C · Owner: American Telephone And Telegraph Company · Inventors: Mollenauer, Linn F.
Overview
Its claims, description and drawings are in the Canadian Patents Database.
Open the CIPO recordAbstract From the Canadian patent
Abstract, Bidirectional lightwave transmission is restored uniform amplification of lightwave signals over long spans of optical fiber is achieved by employing distributed amplification over spans. Distributed amplification is achieved with an amplifying optical fiber which includes a long length of optical fiber having a dilute rare-earth dopant concentration substantially in the fiber core region, and a corresponding pump signal generator at at least one end of the doped fiber having the appropriate wavelength and power to cause amplification of optical signals by both Raman effects and stimulated emission from the rare-earth dopants. Dilute concentrations are understood as the range of …
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Listed from its CIPO record in Patent Yard's archive of Canadian patents past their term. Its claims, description and drawings are in the CIPO record and on Google Patents, and the Claude kit works from them.
Why it's free to use
- Filed August 30, 1990 and granted June 8, 1993. A Canadian patent filed from October 1, 1989 lasts 20 years from filing, so its term ended August 30, 2010.
- A certificate of supplementary protection adds at most two years for a drug, so even that would have ended by August 30, 2012.
- We check Canadian rights only. A patent in its family in another country could still be in force: check its family on Google Patents.
Timeline
Timeline From CIPO dates
Sources & verification
Official CIPO records
Everything on this page comes from the CIPO record linked above. Contains information licensed under the Open Government Licence – Canada.