Progressive power semi-finished spectacle lens blanks for astigmatic presbyopes
US7150527B2 · kind B2 · utility
Assignee
Inventors
Key dates
| Filing date | Aug 17, 2004 |
| Grant date | Dec 19, 2006 |
| Priority date | — |
| Expiry date | Sep 14, 2024 |
Classification
- Technology area (CPC G)Physics
- CPC primaryG02C7/061
- WIPO fieldOptics
- WIPO sectorInstruments
Abstract
An optical lab is provided with a set of different progressive power semi-finished spectacle lens blanks for different combinations of base curve, add power, cylinder and axis, where each semi-finished lens blank in the set has an unfinished surface and a progressive surface with a particular base curve and a particular add power. The progressive surface has been designed to provide optimal optical performance of a lens one surface of which is the progressive surface and another surface of which is a toric surface of a particular non-zero cylinder and a particular axis. Given a prescription of an astigmatic presbyope, the optical lab will select from the set the appropriate semi-finished lens blank and will surface the unfinished surface with the appropriate toric surface so that the progressive power spectacle lens matches the prescription.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.