Zoom lens and imaging apparatus
US7880974B2 · kind B2 · utility
Assignee
Inventors
Key dates
| Filing date | Mar 4, 2010 |
| Grant date | Feb 1, 2011 |
| Priority date | — |
| Expiry date | Mar 4, 2030 |
Classification
- Technology area (CPC G)Physics
- CPC primaryG02B15/143507
- WIPO fieldOptics
- WIPO sectorInstruments
Abstract
A zoom lens includes a negative first lens group, a positive second lens group, and a positive third lens group; wherein, when changing power from a wide-angle end state to a tele end state, the first lens group moves such that air space between the first lens group and the second lens group decreases, and air space between the second lens group and the third lens group increases, and the second lens group moves toward the object side; and wherein the first lens group includes a negative lens with both faces formed aspherically and the concave face facing the image side, and a positive meniscus lens with at least one face formed aspherically and the convex face facing the object side, satisfying2.8<|f1/fw|<3.3where f1 represents the focal length of the first lens group, and fw represents the entire focal length in the wide-angle end state.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.