Simultaneous vision ophthalmic lens for correcting presbyopia and pair of ophthalmic lenses of this kind for the same wearer
US5530491A · kind A · utility
Assignee
Inventors
Key dates
| Filing date | Jan 27, 1994 |
| Grant date | Jun 25, 1996 |
| Priority date | — |
| Expiry date | Jan 27, 2014 |
Classification
- Technology area (CPC G)Physics
- CPC primaryG02C7/06
- WIPO fieldOptics
- WIPO sectorInstruments
Abstract
To define a far vision area and a near vision area in a simultaneous vision ophthalmic lens for correcting presbyopia, the curve representing the proximity as a function of the distance from the axis lies within an area between a lower envelope curve and an upper envelope curve with associated specific polynomial equations in which the coefficients depend on the proximity addition corresponding to the degree of presbyopia of the wearer. Either the far vision area or the near vision area is strengthened relative to the other, the corresponding surface areas S.sub.VL, S.sub.VP being related as follows: PA1 for strengthened near vision: EQU 1.8.ltoreq.S.sub.VL /S.sub.VP .ltoreq.3.6 PA1 and for strengthened far vision: EQU 4.75.ltoreq.S.sub.VL /S.sub.VP
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.