Method for producing porous glass preform for optical fiber
CA 2023445 A1 · Owner: Danzuka, Toshio · Inventors: Danzuka, Toshio; Ohga, Yuichi; Yokota, Hiroshi
Overview
Its claims, description and drawings are in the Canadian Patents Database.
Open the CIPO recordAbstract From the Canadian patent
Abstract, The present invention is directed to a method for producing a porous preform for use in the fabrication of an optical fiber. The method uses at least two burners for synthesizing glass soot particles at least one of which generates a double-layer flame having an inner flame and an outer flame and at least one of which is used for forming a core part of the preform. The method comprises the steps of supplying SiC14 and optionally GeCl4 to the inner flame of the double-layer flame, and SiCl4 to the outer flame of the double-layer flame to flame hydrolyze the supplied compounds to synthesize glass soot particles, supplying SiCl4 and GeCl4 as glass-forming raw materials to the burner …
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 August 16, 1990. No grant is recorded for it in Canada; had it been granted, its 20-year term would have ended August 16, 2010.
- A certificate of supplementary protection adds at most two years for a drug, so even that would have ended by August 16, 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.