Progressive multifocal ophthalmic lens
US8876288B2 · kind B2 · utility
Assignee
Inventors
Key dates
| Filing date | Feb 8, 2011 |
| Grant date | Nov 4, 2014 |
| Priority date | — |
| Expiry date | Aug 7, 2031 |
Classification
- Technology area (CPC G)Physics
- CPC primaryG02C7/063
- WIPO fieldOptics
- WIPO sectorInstruments
Abstract
The invention relates to a finished or semi-finished lens which comprises: a disc containing all the points of the lens that have the same abscissa and the same ordinate as points located within a circle in the reference plane having a diameter of 30 millimeters and centered on the prism reference point; a progression length of less than 14.5 millimeters; a first specific point having a cylinder value equal to the maximum cylinder value of all the points of the lens located in the nasal area and in the disc; and a second specific point having a cylinder value equal to the maximum cylinder value of all the points of the lens located in the temporal area and in the disc; a first ratio between: the maximum gradient of the cylinder for the points of the lens that have the same abscissa and the same ordinate as the points located on segments connecting the mounting cross to the first and second specific points, and surface addition of less than 0.095 per millimeter; and a second ratio between: the maximum cylinder value of the first and second specific points, and surface addition of no more than 0.85. The invention enhances the comfort of the wearer.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.