Zoom lens
US6124983A · kind A · utility
7Cited by
0References
4Claims
0Family size
Assignee
Inventors
Key dates
| Filing date | Aug 20, 1999 |
| Grant date | Sep 26, 2000 |
| Priority date | — |
| Expiry date | Aug 20, 2019 |
Classification
- Technology area (CPC G)Physics
- CPC primaryG02B15/144113
- WIPO fieldOptics
- WIPO sectorInstruments
Abstract
A compact zoom lens having only four lens groups is provided which changes power by shifting a second lens group from the object side along the optical axis, and stabilizes the image plane position by shifting a fourth lens group from the object side along the optical axis. By satisfying three prescribed conditions, magnification of the image is prevented from decreasing for objects at very near distances, and aberrations are favorably corrected so as to provide for high quality imaging over the entire range of zoom for all object distances. At least one lens element has an aspherical surface.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.