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Expired Canadian patentCanada

Uniform illumination of large, thin surfaces particularly suited for automotive applications

CA 2034378 C · Owner: Henkes, John L. · Inventors: Henkes, John L.; Hansler, Richard L.; Davenport, John M.

CIPO record

Overview

Drawings and full text

Its claims, description and drawings are in the Canadian Patents Database.

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Abstract From the Canadian patent

A thin, efficient and uniform illuminator for large areas comprises a plastic wedge of a series of plastic wedges applied to or formed integrally with a back surface of an area to be illuminated. Light is collected and concentrated from a high efficiency light source. The concentrated light is focused as an input to one or more light guides. The light guides may be optical fibers. The light guides or fibers are fused or mated in some other way to an edge or edges of an optically clear plastic wedge or wedges. The wedge shape increases the angle of the internal reflections of the edge coupled light per unit distance and intercepts more of the light as the wedge gets thinner. To further …

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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 January 17, 1991 and granted April 20, 1999. A Canadian patent filed from October 1, 1989 lasts 20 years from filing, so its term ended January 17, 2011.
  • A certificate of supplementary protection adds at most two years for a drug, so even that would have ended by January 17, 2013.
  • We check Canadian rights only. A patent in its family in another country could still be in force: check its family on Google Patents.
FiledJanuary 17, 1991
GrantedApril 20, 1999
Term endedJanuary 17, 2011
Patent numberCA 2034378 C
Classification (IPC)F21S43/23 +2 more

Timeline

Timeline From CIPO dates

1992199419961998200020022004200620082010Application filedJan 17, 1991Patent grantedApril 20, 1999Term endedJan 17, 2011

Sources & verification

Everything on this page comes from the CIPO record linked above. Contains information licensed under the Open Government Licence – Canada.