Manufacture of high proof-test optical fiber using sol-gel
CA 2114560 C · Owner: Johnson, David Wilfred, Jr. · Inventors: Johnson, David Wilfred, Jr.; Bhandarkar, Suhas Dattatreya; Macchesney, John Burnette
Overview
Its claims, description and drawings are in the Canadian Patents Database.
Open the CIPO recordAbstract From the Canadian patent
Optical fiber drawn froth preforms including sol-gel-derived glass is found to contain, small refractory particles of the order of a micron in size. These particles initiate, fiber breaks with the result that fiber may not meet proof-test tensile strength, requirements. An effective separation method relies upon density and/or sire difference from suspended sol particles for separation in the ungelled sol. A preferred separation procedure is centrifugation.
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 January 31, 1994 and granted September 7, 1999. A Canadian patent filed from October 1, 1989 lasts 20 years from filing, so its term ended January 31, 2014.
- A certificate of supplementary protection adds at most two years for a drug, so even that would have ended by January 31, 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.