Multifocal ophthalmic lenses with spherical aberration varying with the addition and the ametropia
US6145987A · kind A · utility
Assignee
Inventors
Key dates
| Filing date | Dec 16, 1998 |
| Grant date | Nov 14, 2000 |
| Priority date | — |
| Expiry date | Dec 16, 2018 |
Classification
- Technology area (CPC G)Physics
- CPC primaryG02C7/042
- WIPO fieldOptics
- WIPO sectorInstruments
Abstract
A multifocal ophthalmic lens is disclosed. The power profile (P) of the lens as a function of the height (h) above the axis (A) of the lens and the addition (Add) corresponding to the degree of presbyopia of the wearer is defined by an equation of the form: EQU P(h)=f(P.sub.VL, Add, h)+C(Add, P.sub.VL)h.sup.2 +B(Add, P.sub.VL) PA1 in which P.sub.VL is the power required for far vision, f is a function of evolution between the near vision and far vision powers, C(Add, P.sub.VL) is a spherical aberration correction coefficient depending on the addition and on the far vision power and B(Add, P.sub.VL) is a power correction coefficient depending on the spherical aberration coefficient.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.