Optical element such as a rear projection screen for an image display device and method of producing same
CA 2103657 C · Owner: Rca Thomson Licensing Corporation · Inventors: Rosati, Dominic Stephen Jr.; Mcclelland, Sandra Kay; Mccoy, Randall Eugene
Overview
Its claims, description and drawings are in the Canadian Patents Database.
Open the CIPO recordAbstract From the Canadian patent
An optical element, such as a rear projection screen for an image display device, comprises at least two substantially rigid sheet members having each a first major surface and a second major surface providing a plane of incidence and a plane of emergence, respectively, through which light is transmitted sequentially. A first sheet member comprises a Fresnel lens and, a second sheet member comprises a lenticular lens array on each of the major surfaces thereof. The plane of emergence on the second major surface of the first sheet member includes the Fresnel lens formed of a radiation curable material. A method of making the Fresnel lens is described.
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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 August 5, 1993 and granted December 2, 1997. A Canadian patent filed from October 1, 1989 lasts 20 years from filing, so its term ended August 5, 2013.
- A certificate of supplementary protection adds at most two years for a drug, so even that would have ended by August 5, 2015.
- 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.