High-efficiency k-sheet polarizer
CA 2207896 C · Owner: Bennett, Stewart · Inventors: Kadaba, Narendra S.; Trapani, Giorgio B.; Cael, John J.
Overview
Its claims, description and drawings are in the Canadian Patents Database.
Open the CIPO recordAbstract From the Canadian patent
This invention relates to a new and improved light-polarizing sheet comprising molecularly oriented polyvinyl alcohol containing an oriented block segment of polyvinylene and said polyvinyl alcohol. In particular the polarizing sheet , comprises a polyvinylalcohol/polyvinylene block copolymer material wherein the polyvinylene blocks thereof are formed by molecular dehydration of a sheet of polyvinylalcohol; said sheet of polyvinylalcohol/polyvinylene block copolymer material comprising a uniform distribution of light-polarizing molecules of polyvinylalcohol/polyvinylene block copolymer material varying in the length n, of the conjugated repeating vinylene unit of the polyvinylene …
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 November 15, 1996 and granted July 24, 2001. A Canadian patent filed from October 1, 1989 lasts 20 years from filing, so its term ended November 15, 2016.
- A certificate of supplementary protection adds at most two years for a drug, so even that would have ended by November 15, 2018.
- 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.