Distributed refractive index optical fiber and method of manufacturing the same
CA 2250249 C · Owner: Nakamura, Kazuki · Inventors: Yamashita, Tomoyoshi; Tahara, Yasuteru; Nakamura, Kazuki
Overview
Its claims, description and drawings are in the Canadian Patents Database.
Open the CIPO recordAbstract From the Canadian patent
A distributed refractive index optical fiber having a multilayer structure of concentric layers made of (co)polymers selected from the group consisting of homopolymers HP1, HP2, ... and HPn manufactured from two or more kinds of monomers M1, M2, ... and Mn and having refractive indexes gradually lowering in this order, and one or more kinds of binary copolymer CP of these monomers. Mixed layers of mixtures of the (co)polymers of the adjacent layers are formed between the adjacent layers. The central portion of the optical fiber has the highest refractive index, and the refractive indexes of the optical fiber decreasing gradually toward the outer circumferential portion thereof. This …
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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 March 28, 1997 and granted July 15, 2003. A Canadian patent filed from October 1, 1989 lasts 20 years from filing, so its term ended March 28, 2017.
- A certificate of supplementary protection adds at most two years for a drug, so even that would have ended by March 28, 2019.
- We check Canadian rights only. A patent in its family in another country could still be in force: check its family on Google Patents.
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Everything on this page comes from the CIPO record linked above. Contains information licensed under the Open Government Licence – Canada.