Progressive multifocal ophthalmic lens with rapid power variation
CA 2436358 C · Owner: Devie, Pierre · Inventors: Devie, Pierre; Ahsbahs, Francoise
Overview
Its claims, description and drawings are in the Canadian Patents Database.
Open the CIPO recordAbstract From the Canadian patent
The invention relates to a progressive multifocal ophthalmic lens having a far vision, region, an intermediate vision region and a near vision region a main , meridian of progression, passing through said three regions and a power addition equal to a difference in mean sphere, between a near vision region control point and a far vision region control point. The lens has, a progression length less than 12 mm defined as the vertical distance between a mounting, center and a point on the meridian where mean sphere is greater than mean sphere at the far, vision control point by 85% of the power addition value. To ensure good visual characteristics, not only around the meridian but also in …
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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 February 1, 2002 and granted July 26, 2011. A Canadian patent filed from October 1, 1989 lasts 20 years from filing, so its term ended February 1, 2022.
- A certificate of supplementary protection adds at most two years for a drug, so even that would have ended by February 1, 2024.
- 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.