Vari-focal spectacles
US6626532B1 · kind B1 · utility
146Cited by
1References
18Claims
0Family size
Assignee
Inventors
Key dates
| Filing date | Jun 9, 1998 |
| Grant date | Sep 30, 2003 |
| Priority date | — |
| Expiry date | Jun 9, 2018 |
Classification
- Technology area (CPC G)Physics
- CPC primaryG02F1/294
- WIPO fieldOptics
- WIPO sectorInstruments
Abstract
Optical elements such as a vari-focal lens element, a vari-focal diffractive optical element and a variable declination prism usable as spectacle lens elements and so on.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.