Signature mark recognition systems
CA 2280564 C · Owner: Sambles, John Roy · Inventors: Lawrence, Christopher Robert; Sambles, John Roy
Overview
Its claims, description and drawings are in the Canadian Patents Database.
Open the CIPO recordAbstract From the Canadian patent
A signature recognition system for identifying an article with a distinctive diffractive element (or elements) and verifying the presence of that element or elements comprising; an article with one or more diffraction gratings impressed thereon the gratings) exhibiting periodic wave surface profiles having a depth-to-pitch ratio .delta. of between 0.1 and 0.5 a source of polarised electromagnetic radiation of wavelength .lambda. such that the pitch G of the periodic wave surface profile of the grating(s) is comparable to an integer multiple n of that wavelength means for directing the source of polarised electromagnetic radiation to the surface of the grating(s) at a plane of incidence …
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 23, 1999 and granted October 25, 2011. A Canadian patent filed from October 1, 1989 lasts 20 years from filing, so its term ended August 23, 2019.
- A certificate of supplementary protection adds at most two years for a drug, so even that would have ended by August 23, 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.