Display device
CA 1293068 C · Owner: Green, Ian M. · Inventors: Green, Ian M.
Overview
Its claims, description and drawings are in the Canadian Patents Database.
Open the CIPO recordAbstract From the Canadian patent
In a liquid crystal display, each pixel is formed of four separately energisable areas which have relative light outputs in the ratio 1:2:4:8 respectively, thereby allowing a range of 16 grey levels to be achieved by appropriate selection of areas. Each of the areas has a number of segments which are spaced-apart, but concentrically arranged in order to have the same average, position so that different bit patterns cause the pixel to change brightness only, without any apparent positional change.
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
- Granted December 10, 1991. A Canadian patent filed before October 1, 1989 lasted 17 years from grant, so its term ended December 10, 2008.
- 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.