Fiber optic switch
CA 2039797 A1 · Owner: Chinn, Stephen R. · Inventors: Chinn, Stephen R.
Overview
Its claims, description and drawings are in the Canadian Patents Database.
Open the CIPO recordAbstract From the Canadian patent
The invention relates to an electrically operated fiber optical switch for circularly polarized light. The switch comprises an input 3-dB fiber optic coupler a Faraday effect fiber optic phase rotator and an output 3-dB fiber optic coupler, all three providing dual fiber optic paths. The input 3-dB coupler divides the light waves between two oppositely wound optical fibers in the Faraday effect phase rotator. The magnetic fields in the phase rotator are adjusted to produce the desired (e.g. ?.pi./2 radians) relative phase delays between the divided light waves the sign of the, relative phase being dependent on current direction. When the light waves are recombined in the output 3-dB …
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 April 4, 1991. No grant is recorded for it in Canada; had it been granted, its 20-year term would have ended April 4, 2011.
- A certificate of supplementary protection adds at most two years for a drug, so even that would have ended by April 4, 2013.
- 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.