Front projection screen
CA 1051237 A · Owner: Qantix Corporation · Inventors: Brown, John W.
Overview
Its claims, description and drawings are in the Canadian Patents Database.
Open the CIPO recordAbstract From the Canadian patent
A front projection screen is disclosed which is made from a transparent material. Prism-like elements are formed on the backside thereof so that light incident upon the screen from a preferred direction will be totally reflected by the screen while light incident upon the screen from other directions will pass therethrough. Sides of the prism-like elements are curved for dispersion in the horizontal plane while the front surface of the projection screen has segments of cylindrical columns formed thereon perpendicular to the prism-like elements to provide an angular spread in the vertical plane. The thickness of the screen is between 30% and 70% of the focal length of the cylindrical columns …
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
- Granted March 27, 1979. A Canadian patent filed before October 1, 1989 lasted 17 years from grant, so its term ended March 27, 1996.
- 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.