Eyeglasses and other lenses of variable focal length and means and method for varying such focal length
US4418990A · kind A · utility
147Cited by
1References
9Claims
0Family size
Assignee
Inventor
Key dates
| Filing date | Jul 20, 1981 |
| Grant date | Dec 6, 1983 |
| Priority date | — |
| Expiry date | Jul 20, 2001 |
Classification
- Technology area (CPC G)Physics
- CPC primaryG02C7/085
- WIPO fieldOptics
- WIPO sectorInstruments
Abstract
An eyeglass apparatus having a variable focal length lens and an associated method for varying the focal length of the lens uses a lens having a focal length which is variable as pressure along the lens is varied. Focal length adjusting mechanisms carried by the eyeglass frames provide for manual or automatic adjustment of the lens focal length.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.