Gradation compensating apparatus for a video signal
CA 2128758 C · Owner: Matsushita Electric Industrial Co. Ltd. · Inventors: Kageyama, Atsuhisa; Kawabata, Minoru
Overview
Its claims, description and drawings are in the Canadian Patents Database.
Open the CIPO recordAbstract From the Canadian patent
A gradation compensating apparatus comprises a skin color detecting circuit for detecting a skin color signal from an inputted color difference signal a, compensation amount controlling circuit for controlling the signal level by the skin color detecting signal as a compensating signal, an APL detecting circuit for detecting an APL level from an inputted luminance signal and for outputting the detected APL level as an APL voltage, an APL controlling circuit for controlling the compensating signal level by the APL voltage an output, circuit for outputting a compensating output voltage by controlling the compensating signal with an inputted do voltage, and a CRT driving circuit for …
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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 July 25, 1994 and granted November 23, 1999. A Canadian patent filed from October 1, 1989 lasts 20 years from filing, so its term ended July 25, 2014.
- A certificate of supplementary protection adds at most two years for a drug, so even that would have ended by July 25, 2016.
- 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.