Method for identifying an optical transmission medium, apparatus for identifying the same and method for optical telecommunication
CA 2011303 C · Owner: Sentsui, Shintaro · Inventors: Mizutani, Morinobu; Fujisaki, Akira; Sentsui, Shintaro
Overview
Its claims, description and drawings are in the Canadian Patents Database.
Open the CIPO recordAbstract From the Canadian patent
A particular optical transmission medium to be identified is excited by means of the polarized light and said polarized light is modulated by applying either an electromagnetic action or a mechanical action to the particular optical transmission medium to be identified at said identification section so that said particular optical transmission medium can be identified by the deviation of the polarized plane of said polarized light.
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 March 1, 1990 and granted October 15, 1996. A Canadian patent filed from October 1, 1989 lasts 20 years from filing, so its term ended March 1, 2010.
- A certificate of supplementary protection adds at most two years for a drug, so even that would have ended by March 1, 2012.
- 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.