Methods and apparatus for producing ophthalmic lenses
CA 2094669 C · Owner: Coburn Optical Industries, Inc. · Inventors: Blocha, John; Hyslop Ronald T.
Overview
Its claims, description and drawings are in the Canadian Patents Database.
Open the CIPO recordAbstract From the Canadian patent
An initial curvature is cut into a lens blank in a lens making machine, such as a lathe and the, curvature is subsequently finished by a finishing tool. The finishing tool has curve characteristics which correspond to those of a prescription within a prescribed tolerance. The curvature of the finishing tool is measured on a digital gauge, and those measurements are fed to a digital controller which actuates the lathe. As a result an initial curvature is cut into the lens blank having characteristics which correspond to those of the finishing tool. The finishing operation can thus be performed more quickly, since less material needs to be removed from the initial curvature during the …
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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 April 22, 1993 and granted February 18, 1997. A Canadian patent filed from October 1, 1989 lasts 20 years from filing, so its term ended April 22, 2013.
- A certificate of supplementary protection adds at most two years for a drug, so even that would have ended by April 22, 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.