Liquid crystal device, driving method thereof, liquid crystal apparatus, and illumination apparatus
CA 2126199 C · Owner: Nippon Hoso Kyokai · Inventors: Hirabayashi, Tsunehiro; Takano, Satoshi; Kashiwagi, Tohru
Overview
Its claims, description and drawings are in the Canadian Patents Database.
Open the CIPO recordAbstract From the Canadian patent
A method of driving a liquid crystal device includes alternately applying voltages causing a composite film (1) to attain an opaque state and a transparent state respectively, changing the time period thereby changing, the ratio of the time period of the opaque state to the time period of the transparent state per unit time period and controlling the power of light transmitted through the composite film (1) per unit time period. A liquid crystal apparatus is provided with a driving circuit (D) for applying the above-described driving voltages to the liquid crystal device (L). An illumination apparatus has the above-described liquid crystal device (L) disposed in the optical path of light …
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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 November 16, 1992 and granted February 22, 2000. A Canadian patent filed from October 1, 1989 lasts 20 years from filing, so its term ended November 16, 2012.
- A certificate of supplementary protection adds at most two years for a drug, so even that would have ended by November 16, 2014.
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Everything on this page comes from the CIPO record linked above. Contains information licensed under the Open Government Licence – Canada.