Projection television apparatus for reducing red-emphasized peripheral screen portions
CA 2027242 C · Owner: Mitsubishi Denki Kabushiki Kaisha · Inventors: Tetsuda, Hiroshi
Overview
Its claims, description and drawings are in the Canadian Patents Database.
Open the CIPO recordAbstract From the Canadian patent
A projection television apparatus is composed of a combination of cathode ray tubes for the three primary colors red, green and blue. The, green and blue cathode ray tubes have a multilayered interference filter disposed on the inner surface thereof and display light on a screen the, intensity of which is varied by the multilayered interference filter passing, through a series of projection lenses positioned in front of the cathode ray tubes. The red cathode ray tube has no multilayered interference filter and produces light having a distribution of luminous intensity nearly equal to that of the green and blue lights. This is achieved by displaying light the luminous intensity of which is …
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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 October 10, 1990 and granted July 20, 1993. A Canadian patent filed from October 1, 1989 lasts 20 years from filing, so its term ended October 10, 2010.
- A certificate of supplementary protection adds at most two years for a drug, so even that would have ended by October 10, 2012.
- 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.