Contrast corrector for video signal
CA 2047149 C · Owner: Matsushita Electric Industrial Co. Ltd. · Inventors: Kageyama, Atsuhisa; Yasue, Hazama
Overview
Its claims, description and drawings are in the Canadian Patents Database.
Open the CIPO recordAbstract From the Canadian patent
For a video apparatus such as a television receiver, a gray level correcting device is provided to correct luminance and color saturation of a video signal thereby making the reproduced image clear and vivid. In this device at least one of the difference between the black level of the luminance signal and a predetermined pedestal voltage and the difference between the white level and a certain white level control voltage is calculated, and the color saturation of a chrominance signal is controlled by the color saturation control voltage added with the calculated difference.
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 July 16, 1991 and granted May 5, 1998. A Canadian patent filed from October 1, 1989 lasts 20 years from filing, so its term ended July 16, 2011.
- A certificate of supplementary protection adds at most two years for a drug, so even that would have ended by July 16, 2013.
- 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.