Method of producing optical-fiber coupler
CA 2061516 C · Owner: Sumitomo Electric Industries, Ltd. · Inventors: Yokota, Hiroshi; Takimoto, Hiroaki; Suganuma, Hiroshi
Overview
Its claims, description and drawings are in the Canadian Patents Database.
Open the CIPO recordAbstract From the Canadian patent
The invention provides a method for, producing an optical-fiber coupler with a preset branching ratio. The present invention relates to a method in which part of a plurality of optical fibers are made to closely contact with each other so as to form a coupler. The coupler is heated to thereby obtain a predetermined branching ratio; the flow rate of a gas to be supplied to a heat source is increased/decreased by a quantity proportional to a difference between the drawing speed and a preset drawing speed while predetermined tension is applied to the optical fibers.
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 February 19, 1992 and granted April 15, 1997. A Canadian patent filed from October 1, 1989 lasts 20 years from filing, so its term ended February 19, 2012.
- A certificate of supplementary protection adds at most two years for a drug, so even that would have ended by February 19, 2014.
- 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.