Method and apparatus for forming aperiodic gratings in optical fibers
CA 2179042 C · Owner: Glenn, William H. · Inventors: Glenn, William H.
Overview
Its claims, description and drawings are in the Canadian Patents Database.
Open the CIPO recordAbstract From the Canadian patent
A method and apparatus for simultaneously exposing an optical fiber (32) made , of a material which has a refractive index that can b e permanently changed by exposure to light of a predetermined intensity at a predetermined wavelength to two writing light beams (268 , 272) which intersect and interfere in a predetermined region (30) of the fiber (32) so as to create an interference pattern along a longi tudinal axis of the fiber (32) for a time long enough , to form a permanent refractive index variation in the waveguide. Each of said two writing beams have a predetermined number of wavelengths each wavelength , being sufficiently different from each other so as to cause said refract …
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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 September 30, 1994 and granted January 6, 1998. A Canadian patent filed from October 1, 1989 lasts 20 years from filing, so its term ended September 30, 2014.
- A certificate of supplementary protection adds at most two years for a drug, so even that would have ended by September 30, 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.