Lens block and method of processing lenses
CA 2301790 A1 · Owner: Ppg Industries Ohio, Inc. · Inventors: Coleman, Charles R.; Smarto, John E.
Overview
Its claims, description and drawings are in the Canadian Patents Database.
Open the CIPO recordAbstract From the Canadian patent
A two-piece lens block (10) allows for the rotation of an edged lens blank (5) in order to align the cylinder of the lens blank (5) correctly. The lens block (10) includes a substantially cylindrical base (12) having a first surface (13) facing the lens blank (5) and an opposed second surface (15) with a plurality of driving recesses (14) extending into the base (12) from the second surface (15). A rotatable ring member (22) surrounds the base (12) and includes a mounting surface (24) generally adjacent to the lens blank (5). An edged lens-shaped cavity (26) is provided in the ring member (22) and provides for nearly full surface contact of an attachment alloy (17) with a front …
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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 June 18, 1999. No grant is recorded for it in Canada; had it been granted, its 20-year term would have ended June 18, 2019.
- A certificate of supplementary protection adds at most two years for a drug, so even that would have ended by June 18, 2021.
- 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.