Zoom lens system, optical apparatus, and method for zooming
US8144403B2 · kind B2 · utility
Assignee
Inventors
Key dates
| Filing date | Jun 14, 2008 |
| Grant date | Mar 27, 2012 |
| Priority date | — |
| Expiry date | Mar 8, 2029 |
Classification
- Technology area (CPC G)Physics
- CPC primaryG02B27/646
- WIPO fieldOptics
- WIPO sectorInstruments
Abstract
Providing a zoom lens system having excellent optical performance, an optical apparatus, and a method for zooming the zoom lens system. The zoom lens system includes, in order from an object, a first lens group G1 having negative refractive power, a second lens group G2 having positive refractive power, and a third lens group G3 having negative refractive power. Upon zooming from a wide-angle end state W to a telephoto end state T, each distance between adjacent lens groups is varied. The first lens group G1 includes, in order from the object, a front group G1a, and a rear group G1b having negative refractive power. Focusing on the object is carried out by moving the rear group G1b along the optical axis.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.