Aspheric plano eyewear
US5825455A · kind A · utility
Assignee
Inventors
Key dates
| Filing date | Feb 26, 1997 |
| Grant date | Oct 20, 1998 |
| Priority date | — |
| Expiry date | Feb 26, 2017 |
Classification
- Technology area (CPC G)Physics
- CPC primaryG02C7/02
- WIPO fieldMedical technology
- WIPO sectorInstruments
Abstract
A novel plano lens and eyewear incorporating such lens is presented wherein the plano lens comprises a front surface curvature which is created by rotating an aspheric shape about an axis which is offset from an axis of the aspheric shape. In a preferred embodiment, the aspheric shape is an ellipse or at least is an aspheric shape, a segment of which has an elliptical arc. This elliptical arc is rotated about an axis spaced (offset) some distance from a major or minor axis of the ellipse. In a more preferred embodiment, the ellipse is rotated about an axis spaced from and parallel to the major or minor axis of the ellipse, but in the same plane as the ellipse. The resulting surface of this preferred lens configuration will have a cross-section in a first axis which is a segment of an ellipse, and a cross-section in a second axis (perpendicular to the first axis) which is a segment of a circle. A significant feature of the preferred front lens configuration is that the surface generated is rotationally symmetric.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.