Diffractive multifocal lens having radially varying light distribution
US7871162B2 · kind B2 · utility
Assignee
Inventor
Key dates
| Filing date | Apr 24, 2008 |
| Grant date | Jan 18, 2011 |
| Priority date | — |
| Expiry date | Apr 24, 2028 |
Classification
- Technology area (CPC G)Physics
- CPC primaryG02C2202/20
- WIPO fieldMedical technology
- WIPO sectorInstruments
Abstract
The present invention provides improved ophthalmic lenses and methods for their design and use. Monofocal and multifocal diffractive ophthalmic lenses having reduced light scatter and/or improved light energy distribution properties are provided. These properties are provided by the diffractive profiles of the invention, often having subtlely shaped echelettes with appropriately curving profiles. Light scatter may be generated by the sharp corners associated with vertical steps between adjacent conventional diffractive echelettes. Smooth diffractive profiles of the invention reduce light scatter. Light energy directed towards non-viewing diffractive orders may have a unwanted effects on vision quality. Diffractive profiles of the invention may limit the light energy in certain, selected orders, thereby improving viewing quality and mitigating unwanted effects such as dysphotopsia. Diffractive profiles of the invention can also vary the light energy distributed between individual echelettes, providing additional advantages in various viewing situations.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.