Apparatus and method for detecting features of fingerprint
CA 2187840 C · Owner: Nec Corporation · Inventors: Sato, Atsushi
Overview
Its claims, description and drawings are in the Canadian Patents Database.
Open the CIPO recordAbstract From the Canadian patent
The detection of fingerprint feature is performed on the basis of a directional distribution of fingerprint obtained by setting a plurality of points on a circle having a center corresponding to a mark point on a directional pattern of ridges, obtaining inner products of vectors indicating tangent lines and vectors indicating ridges at the respective points and providing a distribution of the inner products as a directional distribution of ridges, in the following manner. That is, as the first method, Fourier expansion means Fourier-expands the directional distribution of ridges and outputs Fourier coefficient every frequency component power, calculation means calculates power of every …
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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 October 15, 1996 and granted September 5, 2000. A Canadian patent filed from October 1, 1989 lasts 20 years from filing, so its term ended October 15, 2016.
- A certificate of supplementary protection adds at most two years for a drug, so even that would have ended by October 15, 2018.
- 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.