Method for trimming a spectacle lens
US7253974B2 · kind B2 · utility
Assignee
Inventors
Key dates
| Filing date | Mar 24, 2004 |
| Grant date | Aug 7, 2007 |
| Priority date | — |
| Expiry date | Jun 12, 2024 |
Classification
- Technology area (CPC B)Performing Operations; Transporting
- CPC primaryB24B41/06
- WIPO fieldMachine tools
- WIPO sectorMechanical engineering
Abstract
The invention relates to a method for carrying out the precise trimming of a lens (1), whereby the lens is held between two clamping plates (2, 3) in a given position and the grinding of the periphery of the lens (1) is controlled along a trajectory, the last programmed part of which corresponds to the form (8) desired for the lens. The method comprises a first scanning under weak clamping conditions of a number of points on one face of the lens with scanning of the coordinates of the points (8), forming the trace on said face of the mounting circle, a second scanning, with a significant level of clamping which corresponds to that used on trimming the lens of a second number of points on said face of the lens, an approximate mathematical representation of the face of the lens for each of the two clamping conditions, a calculation of the coordinates for the deformation of the contour of the lens on said face of the lens in the second clamping condition to correct the last programmed part of the grinding trajectory.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.