Form depicting, optical interference authenticating device
CA 1232068 A · Owner: National Research Council Of Canada · Inventors: Ho, Fang C.; Dobrowolski, Jerzy A.; Waldorf, Allan J.
Overview
Its claims, description and drawings are in the Canadian Patents Database.
Open the CIPO recordAbstract From the Canadian patent
Jerzy A. Dobrowolski, Fang C. Ho Allan J. Waldorf, ABSTRACT OF THE DISCLOSURE A hard to simulate, readily distinguishable from counterfeits optical interference authenticating device comprises a substrate and at, least one optical interference form depicting coating on the substrate and partially covering the substrate to delineate a known distinct and, readily distinguishable form thereon. The said at least one optical interference coating comprises at least one optical interference layer having known spectral reflectance and spectral transmittance characteristics when viewed at at least one particular angle so that the form is visible in particular colouration at the or each said …
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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
- Granted January 26, 1988. A Canadian patent filed before October 1, 1989 lasted 17 years from grant, so its term ended January 26, 2005.
- 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.