Zoom lens system having two lens units
US6025961A · kind A · utility
24Cited by
3References
32Claims
0Family size
Assignee
Inventors
Key dates
| Filing date | Apr 7, 1998 |
| Grant date | Feb 15, 2000 |
| Priority date | — |
| Expiry date | Apr 7, 2018 |
Classification
- Technology area (CPC G)Physics
- CPC primaryG02B15/177
- WIPO fieldOptics
- WIPO sectorInstruments
Abstract
A zoom lens system has a first lens unit and a second lens unit from the object side. The first lens unit has a negative optical power. The second lens unit has a positive optical power. The second lens unit is arranged on the image side of the first lens unit. An air space between the first and second units is variable for zooming. The second lens unit has a doublet lens element composed of a positive lens element and a negative lens element cemented together.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.