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Expired Canadian patentCanada

Hierarchical constrained automatic learning network for character recognition

CA 2015740 C · Owner: Ncr Corporation · Inventors: Jackel, Lawrence D.; Lecun, Yann; Denker, John S.

CIPO record

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Abstract From the Canadian patent

Highly accurate, reliable optical character recognition is afforded by a layered network having several layers of constrained feature detection wherein each layer of constrained feature detection includes a plurality of constrained feature maps and a corresponding plurality of feature reduction maps. Each feature reduction map is connected to only one constrained feature map in the same layer for undersampling that constrained feature map. Units in each constrained feature map of the first constrained feature detection layer respond as a function of a corresponding kernel and of different portions of the pixel image of the character captured in a receptive field associated with the unit. …

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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 April 30, 1990 and granted January 16, 1996. A Canadian patent filed from October 1, 1989 lasts 20 years from filing, so its term ended April 30, 2010.
  • A certificate of supplementary protection adds at most two years for a drug, so even that would have ended by April 30, 2012.
  • We check Canadian rights only. A patent in its family in another country could still be in force: check its family on Google Patents.
FiledApril 30, 1990
GrantedJanuary 16, 1996
Term endedApril 30, 2010
Patent numberCA 2015740 C
Classification (IPC)G06K9/00 +2 more

Timeline

Timeline From CIPO dates

1991199319951997199920012003200520072009Application filedApril 30, 1990Patent grantedJan 16, 1996Term endedApril 30, 2010

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Everything on this page comes from the CIPO record linked above. Contains information licensed under the Open Government Licence – Canada.