Method and devices for wavelength and power demodulation based on the use of a quantum well electroabsorption filtering detector
CA 2190804 C · Owner: Coroy, Trenton G. · Inventors: Coroy, Trenton G.
Overview
Its claims, description and drawings are in the Canadian Patents Database.
Open the CIPO recordAbstract From the Canadian patent
Devices for measuring one or more properties of a light signal is disclosed. More particularly the invention relates to devices for wavelength and power demodulation based on the use of quantum well electroabsorption photodiodes. In one aspect the invention provides and power and wavelength demodulation system based on a quantum well electroabsorption (QWEA) filtering detector. The input optical signal passes through an optical beam splitter with part of the signal input into a filtering detector which is a multiple quantum well electroabsorption (MQW EA) photodiode having a tunable bandgap and the other part into a reference detector. The input light signal is impinged on the QW diode …
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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 November 20, 1996 and granted February 18, 2003. A Canadian patent filed from October 1, 1989 lasts 20 years from filing, so its term ended November 20, 2016.
- A certificate of supplementary protection adds at most two years for a drug, so even that would have ended by November 20, 2018.
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Official CIPO records
Everything on this page comes from the CIPO record linked above. Contains information licensed under the Open Government Licence – Canada.