Contact lens for correction of irregular astigmatism
US8789945B2 · kind B2 · utility
Assignees
Inventors
Key dates
| Filing date | Mar 24, 2011 |
| Grant date | Jul 29, 2014 |
| Priority date | — |
| Expiry date | May 1, 2031 |
Classification
- Technology area (CPC G)Physics
- CPC primaryG02C2202/22
- WIPO fieldOptics
- WIPO sectorInstruments
Abstract
Disclosed is an implementation of new technology for effectively providing a contact lens capable of achieving satisfactory corrective effects even with respect to irregular astigmatism (residual irregular astigmatism) caused by a conical cornea and so forth, which could not be corrected with conventional eye glasses or contact lens, wherein the contact lens is not dependent on being made to order for each wearer but is industrially mass-producible by means of a practical and novel structure. A contact lens for correction of irregular astigmatism is disclosed wherein a positive correction area (27) is provided on one side of a special radial line (30) and a negative correction area (28) is provided on another side while in any of the correction areas (27, 28) a lens power is configured so that an absolute value becomes progressively larger from an outer peripheral edge part towards a central portion.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.