Tunable optical fiber bragg and long period grating
CA 2318905 A1 · Owner: Chowdhury, Dipakbin Q. · Inventors: Chowdhury, Dipakbin Q.; Sparks, Kevin B.
Overview
Its claims, description and drawings are in the Canadian Patents Database.
Open the CIPO recordAbstract From the Canadian patent
Disclosed is a tunable optical filter which may be used in telecommunications systems. The filter comprises a single mode optical waveguide containing a grating. The resonance wavelength of the filter is changed by changing the boundary condition at the interface between the cladding layer (14) and an additional layer (16) applied to the outer cladding layer surface. This boundary condition is changed by changing the refractive index of the additional layer (16). Means for changing the refractive index of the additional layer (16) include establishing a structural resonance in the additional layer, or forming the additional layer from electro-optic or piezoelectric materials.
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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 March 16, 1999. No grant is recorded for it in Canada; had it been granted, its 20-year term would have ended March 16, 2019.
- A certificate of supplementary protection adds at most two years for a drug, so even that would have ended by March 16, 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
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.