Manufacture of high proof-test optical fiber
CA 2116383 C · Owner: American Telephone And Telegraph Company · Inventors: Bhandarkar, Suhas D.
Overview
Its claims, description and drawings are in the Canadian Patents Database.
Open the CIPO recordAbstract From the Canadian patent
Incidence of breakage in optical fiber drawn from sol-gel produced preforms is reduced by treatment of the still-porous glass by use of a chlorine-containing, oxygen-free gas mixture. Improved satisfaction of proof-test requirements to at least 100 kpsi is assured by size reduction of unassimilated discrete particles in the fiber.
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 24, 1994 and granted December 30, 1997. A Canadian patent filed from October 1, 1989 lasts 20 years from filing, so its term ended February 24, 2014.
- A certificate of supplementary protection adds at most two years for a drug, so even that would have ended by February 24, 2016.
- 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.