Indirect ophthalmoscopy contact lens device with compound contact lens element
CA 2177193 C · Owner: Volk Optical, Inc. · Inventors: Volk, Donald A.
Overview
Its claims, description and drawings are in the Canadian Patents Database.
Open the CIPO recordAbstract From the Canadian patent
An indirect ophthalmoscopy contact lens device includes a contact lens having a first posterior lens surface with a concave shape substantially corresponding to the shape of an average cornea and an image forming lens for collecting and focussing light exiting the patient's eye and entering the contact lens when in place on the patient's eye for forming an aerial image of the fundus of the patient's eye. The contact lens comprises a compound contact lens element including a posterior lens portion cemented to an anterior lens portion . The posterior lens portion includes the first posterior lens surface and a first anterior lens surface and is made of a material having a first index of …
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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 May 23, 1996 and granted December 21, 1999. A Canadian patent filed from October 1, 1989 lasts 20 years from filing, so its term ended May 23, 2016.
- A certificate of supplementary protection adds at most two years for a drug, so even that would have ended by May 23, 2018.
- 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.