Varifocal lens assembly
US3972056A · kind A · utility
70Cited by
3References
6Claims
0Family size
Assignee
Inventors
Key dates
| Filing date | Dec 4, 1974 |
| Grant date | Jul 27, 1976 |
| Priority date | — |
| Expiry date | Dec 4, 1994 |
Classification
- Technology area (CPC G)Physics
- CPC primaryG02B15/144
- WIPO fieldOptics
- WIPO sectorInstruments
Abstract
A varifocal lens assembly of a type including at least two lens groups, a first lens group being axially movable parallel to the optical axis of the varifocal lens assembly for varying the focal length of the optical system of the varifocal lens assembly. An automatic focusing device is associated with the varifocal lens assembly to axially move the lens groups as a whole, the other or second lens group or a part of lens elements of the other or second lens group a predetermined distance to compensate for the image shift which takes place during the adjustment of the focal length effected by axially moving the first lens group.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.