Zoom lens
US9001432B2 · kind B2 · utility
Assignees
Inventor
Key dates
| Filing date | Dec 31, 2013 |
| Grant date | Apr 7, 2015 |
| Priority date | — |
| Expiry date | Dec 31, 2033 |
Classification
- Technology area (CPC G)Physics
- CPC primaryG02B15/1461
- WIPO fieldOptics
- WIPO sectorInstruments
Abstract
A zoom lens includes a first lens group, a second lens group, a third lens group and a fourth lens group, all of which are arranged in sequence from an object side to an image side along an optical axis. The first lens group is with positive refractive power. The second lens group is with negative refractive power. The third lens group is with positive refractive power. The fourth lens group is with positive refractive power. The first lens group includes a first lens and a second lens, both of which are arranged in sequence from the object side to the image side along the optical axis, wherein the first lens group and the first lens satisfy the following condition: −1.2<fG1/f1<−0.58, wherein fG1 is an effective focal length of the first lens group and f1 is an effective focal length of the first lens.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.