Zoom lens system
US6456443B2 · kind B2 · utility
13Cited by
2References
20Claims
0Family size
Assignee
Inventors
Key dates
| Filing date | Mar 19, 2001 |
| Grant date | Sep 24, 2002 |
| Priority date | — |
| Expiry date | Mar 19, 2021 |
Classification
- Technology area (CPC G)Physics
- CPC primaryG02B15/143507
- WIPO fieldOptics
- WIPO sectorInstruments
Abstract
A zoom lens system has, from the object side, a first lens unit, a second lens unit and a third lens unit. The first lens unit has a negative optical power as a whole. The second and third lens units have a positive optical power as a whole. In the zoom lens system, zooming is achieved by varying the distance between the first and second lens units, and at least one of the lens elements is a plastic lens element.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.