Video signal gradation corrector
CA 2062609 C · Owner: Matsushita Electric Industrial Co. Ltd. · Inventors: Kageyama, Atsuhisa; Tsuji, Toshiaki
Overview
Its claims, description and drawings are in the Canadian Patents Database.
Open the CIPO recordAbstract From the Canadian patent
In a video signal gradation corrector used in a television receiver, an output of a look-up table memory is supplied to a constant-multiplication circuit an, output signal of the constant-multiplication circuit and an output signal of a look-up table operating circuit are added by an adder, and the result of addition is set into the look-up table memory. Further, a video scene change detecting circuit is be provided between an output terminal of the look-up table operating circuit and a coefficient control terminal of the, constant-multiplication circuit and a coefficient of the, constant-multiplication circuit is changed in accordance with a change in video scene. Thereby, a correction is …
Read the whole patent
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 March 10, 1992 and granted September 2, 1997. A Canadian patent filed from October 1, 1989 lasts 20 years from filing, so its term ended March 10, 2012.
- A certificate of supplementary protection adds at most two years for a drug, so even that would have ended by March 10, 2014.
- 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.