High contrast distorted helix effect electro-optic devices and tight ferroelectric pitch ferroelectric liquid crystal compositions useful therein
CA 2088934 C · Owner: Handschy, Mark A. · Inventors: Vohra, Rohini T.; Handschy, Mark A.; Escher, Claus
Overview
Its claims, description and drawings are in the Canadian Patents Database.
Open the CIPO recordAbstract From the Canadian patent
High-contrast electro-optic device contain non-surface stabilized FLC cells which retain a helical diameter (~) structure and exhibit a change in optical anisotropy as a function of the magnitude of an applied electric field or driving voltage. The FLC cells incorporate chiral ferroelectric liquid crystals which exhibit a ferroelectric phase and a chiral nematic (N*) phase at temperatures above the ferroelectric phase and comprise uniformly spaced electrode-containing plates between which the FLC is aligned. The cell is provided with means for detecting the change in optical anisotropy in the FLC induced by the application of the electric field.
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 February 8, 1993 and granted June 3, 2003. A Canadian patent filed from October 1, 1989 lasts 20 years from filing, so its term ended February 8, 2013.
- A certificate of supplementary protection adds at most two years for a drug, so even that would have ended by February 8, 2015.
- 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.