Viewing apparatus
CA 2113479 C · Owner: Richmond Holographic Research And Development Limited · Inventors: Trayner, David John; Orr, Edwina Margaret
Overview
Its claims, description and drawings are in the Canadian Patents Database.
Open the CIPO recordAbstract From the Canadian patent
Viewing apparatus for providing a, viewer with an apparent 3-D image comprises a diffusing holographic optical element (HOE) screen (15), means (17, 19) for illuminating the screen (15) from a plurality of different positions and means (14) for effecting spatial modulation of the light from the respective positions so as to illuminate respective images on the screen (15). The arrangement is such as to provide a plurality of viewing zones (18 20) whereby each image can be seen only from a corresponding one of the zones, (18 20).
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 July 15, 1992 and granted April 23, 2002. A Canadian patent filed from October 1, 1989 lasts 20 years from filing, so its term ended July 15, 2012.
- A certificate of supplementary protection adds at most two years for a drug, so even that would have ended by July 15, 2014.
- 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.