Mode field diameter conversion fiber
CA 2096182 C · Owner: Sumitomo Electric Industries, Ltd. · Inventors: Tomita, Shigeru; Nishimura, Masayuki; Kanamori, Hiroo
Overview
Its claims, description and drawings are in the Canadian Patents Database.
Open the CIPO recordAbstract From the Canadian patent
There is disclosed an optical waveguide comprising a core portion made of a light propagating material and a cladding portion, a first dopant and a second dopant being induced into said core portion, the first dopant having a function of increasing a refractive index of the light propagating material and having a first thermal diffusion coefficient to said light propagating material the second dopant having a function of decreasing the refractive index of said light propagating material and having a second thermal diffusion coefficient to the light propagating material larger than the first thermal diffusion coefficient under a predetermined temperature.
Read the whole patent
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 May 13, 1993 and granted December 5, 2000. A Canadian patent filed from October 1, 1989 lasts 20 years from filing, so its term ended May 13, 2013.
- A certificate of supplementary protection adds at most two years for a drug, so even that would have ended by May 13, 2015.
- 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
Timeline From CIPO dates
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.