Progressive lens
CA 2251948 A1 · Owner: Varnas, Saulius Raymond · Inventors: Varnas, Saulius Raymond; Kris, Dimitrios Jack; Edwards, Simon John
Overview
Its claims, description and drawings are in the Canadian Patents Database.
Open the CIPO recordAbstract From the Canadian patent
A progressive ophthalmic lens element including a lens surface having upper viewing zone providing good optical quality at a predetermined low surface power over a large area of vision; said predetermined power being determined by the viewer's distance prescription (Rx) the horizontal fitting position normally being determined by the inter pupillary distance of the wearer and , the vertical fitting position normally being determined by the vertical frame midpoint; a lower viewing zone of higher surface power providing an enhanced range of vision for intermediate or lesser viewing distances; and a corridor of relatively low astigmatism extending therebetween; wherein the contours of …
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 April 17, 1997. No grant is recorded for it in Canada; had it been granted, its 20-year term would have ended April 17, 2017.
- A certificate of supplementary protection adds at most two years for a drug, so even that would have ended by April 17, 2019.
- 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.