Waveguide-type optical multiplexer/demultiplexer
CA 2411228 A1 · Owner: Hitachi Cable, Ltd. · Inventors: Uetsuka, Hisato; Arai, Hideaki; Chiba, Takafumi
Overview
Its claims, description and drawings are in the Canadian Patents Database.
Open the CIPO recordAbstract From the Canadian patent
A waveguide-type optical multiplexer/demultiplexer with low crosstalk characteristics and reduced wavelength dispersion is provided. A waveguide-type optical multiplexer/demultiplexer comprising, first, second and third optical multiplexer/demultiplexer circuits connected in multistage, each, multiplexer/demultiplexer circuit has four input-output ports third input-output pork of first optical multiplexer/demultiplexer circuit is connected to third input-output port of second optical multiplex/demultiplexer circuit, and fourth input-output port of first optical multiplexer/demultiplexer circuit is connected to fourth input-output port of third optical multiplexer/demultiplexer circuit, when …
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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 6, 2002. No grant is recorded for it in Canada; had it been granted, its 20-year term would have ended November 6, 2022.
- A certificate of supplementary protection adds at most two years for a drug, so even that would have ended by November 6, 2024.
- 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.