Bifocal contact lens
CA 2553754 C · Owner: Alcon Inc. · Inventors: Ehrmann, Klaus; Du Toit, Renee; Falk, Darrin Mark
Overview
Its claims, description and drawings are in the Canadian Patents Database.
Open the CIPO recordAbstract From the Canadian patent
A contact lens having near vision and distance vision portions the lens being , movable on the eye between first and second positions those positions , corresponding with aligning the wearer's vision through the near vision and distance vision portions respectively. The lens is positionally stable on the eye in each of the two positions, and requires a force to be applied to the lens to move between the first and second positions. Preferably the lens has a back surface and a front surface, and said back surface has either one or two major back curve zones occupying a major portion of the lens back surface.
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 January 28, 2005 and granted December 30, 2014. A Canadian patent filed from October 1, 1989 lasts 20 years from filing, so its term ended January 28, 2025.
- Certificates of supplementary protection extend only drug patents, and it isn't classified as one.
- 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.