N x m optical wavelength routing switch
CA 2285283 C · Owner: Chorum Technologies Lp · Inventors: Wu, Kuang-Yi; Liu, Jian-Yu
Overview
Its claims, description and drawings are in the Canadian Patents Database.
Open the CIPO recordAbstract From the Canadian patent
A switchable wavelength router switches wavelength division multiplexed (WDM) optical signals between N input ports (101 102) and M output ports (103, 104, 105). Each WDM signal is spatially decomposed into N pairs of orthogonally polarized beams by a polarization-dependent routing element such as a , birefringent element (201). A polarization rotator array (204) rotates the polarization of each beam pair so that both beams in each pair have the same polarization. A wavelength filter (206) then demultiplexes each beam pair to create N sets of four beams. A second polarization-dependent routing element (202) spatially routes the four beams in each of the N sets based on their …
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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 April 7, 1998 and granted January 15, 2002. A Canadian patent filed from October 1, 1989 lasts 20 years from filing, so its term ended April 7, 2018.
- A certificate of supplementary protection adds at most two years for a drug, so even that would have ended by April 7, 2020.
- 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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Official CIPO records
Everything on this page comes from the CIPO record linked above. Contains information licensed under the Open Government Licence – Canada.