Expired Canadian patentCanada
Digital half-toning process with error diffusion
CA 2000705 C · Owner: Bowers, John S. · Inventors: Bowers, John S.; Bowers, Harry
Overview
Drawings and full text
Its claims, description and drawings are in the Canadian Patents Database.
Open the CIPO recordAbstract From the Canadian patent
A digital half-toning process with error diffusion reduces visibly discernible artifacts. In the error diffusion process, a range function provides random factors which are used to spread errors to neighboring pixels.
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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 13, 1989 and granted September 14, 1999. A Canadian patent filed from October 1, 1989 lasts 20 years from filing, so its term ended October 13, 2009.
- A certificate of supplementary protection adds at most two years for a drug, so even that would have ended by October 13, 2011.
- We check Canadian rights only. A patent in its family in another country could still be in force: check its family on Google Patents.
FiledOctober 13, 1989
GrantedSeptember 14, 1999
Term endedOctober 13, 2009
Patent numberCA 2000705 C
Classification (IPC)G06F3/12 +2 more
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.