Three tube color projection system having at least one tube without an interference filter
CA 2016379 C · Owner: Tsukagoshi, Kazuo · Inventors: Kawamura, Hiroshi; Tsukagoshi, Kazuo
Overview
Its claims, description and drawings are in the Canadian Patents Database.
Open the CIPO recordAbstract From the Canadian patent
A projection television system having three cathode ray tubes one of which has a display window a fluorescent material, layer disposed on the innermost of the display window and a, multilayered interference filter disposed between the display window and the fluorescent material layer and being composed of a number of layers which are alternately manufactured from a high refractive index material and a low refractive index material and also at most two of which have only the display window and the fluorescent material layer whereby images are, produced with as high brightness as by the conventional projection system by means of a beam current supply which is increased as much to compensate a …
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 May 9, 1990 and granted July 20, 1993. A Canadian patent filed from October 1, 1989 lasts 20 years from filing, so its term ended May 9, 2010.
- A certificate of supplementary protection adds at most two years for a drug, so even that would have ended by May 9, 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.