Method and system for preventing low order optical transmission modes in a multimode optical fiber computer network using an annulus laser
CA 2324569 C · Owner: Kirk, Richard L. · Inventors: Kirk, Richard L.; Schofield, Bruce A.; Hutchison, Jerry D.
Overview
Its claims, description and drawings are in the Canadian Patents Database.
Open the CIPO recordAbstract From the Canadian patent
A method for improving modal bandwidth in computer networks using multimode optical fiber and laser sources is disclosed in which an annular beam is generated by the laser source, thus preventing center fiber transmission modes from reaching the detector. This prevents or lessens a pulse-splitting effect at the detector. The annular beam is generated by configuring a vertical cavity surface emitting laser to have a center totally-reflecting block of 5-7 microns to generate a substantially dark-centered beam.
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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 May 21, 1999 and granted February 4, 2003. A Canadian patent filed from October 1, 1989 lasts 20 years from filing, so its term ended May 21, 2019.
- A certificate of supplementary protection adds at most two years for a drug, so even that would have ended by May 21, 2021.
- 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
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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.