Method and apparatus for manufacturing composite lenses
CA 2182720 C · Owner: Iyer, Venkatramani S. · Inventors: Iyer, Venkatramani S.; Blum, Ronald D.; Gupta, Amitava
Overview
Its claims, description and drawings are in the Canadian Patents Database.
Open the CIPO recordAbstract From the Canadian patent
A method for making improved optical quality lenses is described. The method includes arranging a mold (13) having a molding surface a curable, optical quality resin composition and a plastic lens preform (11) of optical quality material such that the resin composition (16) is disposed between and, in contact with the plastic lens preform (11) and the mold (13). Upon curing the resin composition forms a cured plastic attached portion that is bonded to the plastic lens preform. The resin composition and plastic lens preform (11) are selected such that the attached portion has a higher scratch resistance a lowerchromatic aberration, and/or a higher ease of edging than the lens preform.
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 March 16, 1995 and granted January 25, 2000. A Canadian patent filed from October 1, 1989 lasts 20 years from filing, so its term ended March 16, 2015.
- A certificate of supplementary protection adds at most two years for a drug, so even that would have ended by March 16, 2017.
- 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.