Zoom lens system
US6384985B1 · kind B1 · utility
3Cited by
10References
33Claims
0Family size
Assignee
Inventor
Key dates
| Filing date | Sep 21, 1998 |
| Grant date | May 7, 2002 |
| Priority date | — |
| Expiry date | Sep 21, 2018 |
Classification
- Technology area (CPC G)Physics
- CPC primaryG02B15/144113
- WIPO fieldOptics
- WIPO sectorInstruments
Abstract
A zoom lens system has a first lens unit having a positive optical power, a second lens unit having a negative optical power, a third lens unit, and a fourth lens unit. In this zoom lens system, a zooming operation is performed by varying distances between the first, second, third, and fourth lens units, and the following condition is fulfilled:0.4<|&phgr;2/&phgr;W|<0.8where&phgr;2 represents an optical power of the second lens unit; and&phgr;W represents an optical power of the entire zoom lens system at the wide-angle end.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.