Modulation system for projection display
CA 2018151 C · Owner: Goldenberg, Jill Forer · Inventors: Timmers, Wilhelmus Adrianus Gerardus; Goldenberg, Jill Forer
Overview
Its claims, description and drawings are in the Canadian Patents Database.
Open the CIPO recordAbstract From the Canadian patent
In a liquid crystal projection t.v, system the color gradient over the projected image, which is due to angular sensitivity of the dichroic mirrors, is minimized by introducing a field lens (61,62,53) next to the light values or LC-panels (21 22, 23) in the, light paths of the blue (b B) green (b G) and red (b R) beams. By, chosing different length light paths before and after the light valves and LC-panels a difference in angular sensitivity of the separation mirror (41,42) and the recombination mirrors (52,53) can be compensated for.
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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 June 4, 1990 and granted February 13, 2001. A Canadian patent filed from October 1, 1989 lasts 20 years from filing, so its term ended June 4, 2010.
- A certificate of supplementary protection adds at most two years for a drug, so even that would have ended by June 4, 2012.
- We check Canadian rights only. A patent in its family in another country could still be in force: check its family on Google Patents.
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.