Method and apparatus for contactless measurement of the radius of curvature of an ophthalmic article
US7495753B2 · kind B2 · utility
Assignee
Inventors
Key dates
| Filing date | Dec 8, 2005 |
| Grant date | Feb 24, 2009 |
| Priority date | — |
| Expiry date | Dec 8, 2025 |
Classification
- Technology area (CPC G)Physics
- CPC primaryG01M11/025
- WIPO fieldMeasurement
- WIPO sectorInstruments
Abstract
The invention relates to a method and to apparatus for contactlessly measuring the curvature of an ophthalmic article (1) having a “front” face (1B) that presents said curvature. The method consists in: sequentially emitting at least two light beams (L1, L2) onto said front face, these two light beams being offset by a certain angle (α) and converging substantially onto said front face, one of said emitted light beams (L1) being substantially centered on said front face and being substantially normal to said front face; analyzing the wave fronts of the resulting reflected beams (L′1, L′2) in order to determine their respective focuses (F1, F2) therefrom; and deducing the radius of curvature of said face; said operations being performed in such a manner that said emitted beams are substantially not reflected by the rear face of said article.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.