Display system
CA 2079352 C · Owner: International Business Machines Corporation · Inventors: Asada, Shigeki; Sohda, Masayuki; Yasuda, Hiroaki
Overview
Its claims, description and drawings are in the Canadian Patents Database.
Open the CIPO recordAbstract From the Canadian patent
A personal computer generates first gray level signals each dot of which is represented by N bits (where N is an integer larger than or equal to 2) representing 2N (the Nth. power of 2) gray levels. The first gray level signal is supplied to a CRT display, each dot of which displays 2N (the Nth. power of 2) gray levels. Now the CRT is replaced by an LCD, each dot of which displays 2M (the Mth. power of 2) gray levels. An algorithm converts the first gray level signal of N bits representing 2N gray levels to second gray level signals representing 2M gray levels. The second gray level signals are applied to the LCD. The invention solves a problem raised when an algorithm is used to generate …
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 September 24, 1992 and granted May 13, 1997. A Canadian patent filed from October 1, 1989 lasts 20 years from filing, so its term ended September 24, 2012.
- A certificate of supplementary protection adds at most two years for a drug, so even that would have ended by September 24, 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.