Projection television apparatus
CA 2010330 C · Owner: Tetsuda, Hiroshi · Inventors: Kawamura, Hiroshi; Tetsuda, Hiroshi; Tuskagoshi, Kazuo
Overview
Its claims, description and drawings are in the Canadian Patents Database.
Open the CIPO recordAbstract From the Canadian patent
In a projection television apparatus, a color selecting means is located on an optical light path passing through a cathode ray tube and a series of projection lenses disposed in front of the cathode ray tube. This color selecting means has a high reflection factor or a high absorption factor to light having a wavelength of at most 520 nm. With this color selecting means, the range of color reproduction can be much more improved, thus causing an increased degree of color purity of green at the central and peripheral areas of the cathode ray tube.
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 February 19, 1990 and granted May 24, 1994. A Canadian patent filed from October 1, 1989 lasts 20 years from filing, so its term ended February 19, 2010.
- A certificate of supplementary protection adds at most two years for a drug, so even that would have ended by February 19, 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.