Directional coupler type optical device and a driving method therefor
CA 2070259 A1 · Owner: Yanagawa, Hisaharu · Inventors: Yanagawa, Hisaharu; Mak, Hon-Ming
Overview
Its claims, description and drawings are in the Canadian Patents Database.
Open the CIPO recordAbstract From the Canadian patent
A l-input/2-output or 2-input/2-output directional coupler type optical device comprising a junction including two optical waveguides arranged parallel to each other and each fitted with an electrode for controlling a propagation constant the, incidence end or ends of one or both of the optical waveguides being connected to curved or straight optical waveguides, thus forming an incidence-side lead section, and the respective emergence ends of the two optical waveguides being optically connected to curved or straight optical waveguides, thus forming an emergence-side lead section. An electrode for suppressing the mode coupling is mounted on each optical waveguide of the emergence- or …
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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 June 2, 1992. No grant is recorded for it in Canada; had it been granted, its 20-year term would have ended June 2, 2012.
- A certificate of supplementary protection adds at most two years for a drug, so even that would have ended by June 2, 2014.
- 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
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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.