Brightness modulation circuit
CA 2111422 C · Owner: Matsushita Electric Industrial Co. Ltd. · Inventors: Kawashima, Masahiro
Overview
Its claims, description and drawings are in the Canadian Patents Database.
Open the CIPO recordAbstract From the Canadian patent
A brightness modulation circuit for a video display unit has a brightness level adjusting circuit including a memory (13) for storing data representing a suitable degree of brightness modulation corresponding to various types of uses of television systems, and a horizontal digital/analog converter (6) and a vertical digital/analog converter (7) issuing amplitude-modulated parabolic waves, which control the degree of the brightness modulation using the data read from the memory (13).
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 December 14, 1993 and granted May 13, 1997. A Canadian patent filed from October 1, 1989 lasts 20 years from filing, so its term ended December 14, 2013.
- A certificate of supplementary protection adds at most two years for a drug, so even that would have ended by December 14, 2015.
- 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.