Methods of and apparatus for optical signal transmission
CA 2295390 C · Owner: Habel, Richard R. · Inventors: O'Sullivan, Maurice S.; Habel, Richard R.; Roberts, Kim B.
Overview
Its claims, description and drawings are in the Canadian Patents Database.
Open the CIPO recordAbstract From the Canadian patent
A binary signal is encoded to produce a three-level encoded signal having reduced, bandwidth and small low frequency and d.c. components e.g. using modified , duobinary, encoding the encoded signal directly modulating a semiconductor laser to produce a, frequency modulated optical signal which is passed through an interference filter to, provide two-state amplitude modulation from the three-state frequency modulation for, direct recovery of the binary signal by an optical receiver the interference , filter providing, constructive and destructive interference for frequencies corresponding to binary one and, zero bits respectively. An array transmission system can be provided by …
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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 January 13, 2000 and granted December 23, 2003. A Canadian patent filed from October 1, 1989 lasts 20 years from filing, so its term ended January 13, 2020.
- A certificate of supplementary protection adds at most two years for a drug, so even that would have ended by January 13, 2022.
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Timeline
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Everything on this page comes from the CIPO record linked above. Contains information licensed under the Open Government Licence – Canada.