Light distributing tubes and methods of forming same
CA 2240551 C · Owner: Johanson, Walter A. · Inventors: Johanson, Walter A.
Overview
Its claims, description and drawings are in the Canadian Patents Database.
Open the CIPO recordAbstract From the Canadian patent
Method and apparatus for forming hollow tubular light-distributing tubes for area illumination along the length of the tubes from a beam of light introduced into one end. Within the tube is a geometrically complex, 3-dimensional light redirecting structure traversing the light beam along the full length of the tube to redirect the light beam proportionately along the length of tube through a window formed therein. Both the tube and the light-redirecting structure can be formed as an integrated flat substantially void-free structure for shipping and then converted in situ to the operative, 3 dimensional configuration.
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 June 12, 1998 and granted September 9, 2003. A Canadian patent filed from October 1, 1989 lasts 20 years from filing, so its term ended June 12, 2018.
- A certificate of supplementary protection adds at most two years for a drug, so even that would have ended by June 12, 2020.
- 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.