Taking lens device
US6449433B2 · kind B2 · utility
Assignee
Inventors
Key dates
| Filing date | Apr 5, 2001 |
| Grant date | Sep 10, 2002 |
| Priority date | — |
| Expiry date | Apr 5, 2021 |
Classification
- Technology area (CPC G)Physics
- CPC primaryG02B15/1461
- WIPO fieldOptics
- WIPO sectorInstruments
Abstract
A taking lens device has a zoom lens system having an optical system that is comprised of a plurality of lens units and that achieves zooming by varying the unit-to-unit distances and an image sensor that converts an optical image formed by the zoom lens system into an electric signal. The zoom lens system is comprised of, from the object side, a first lens unit having a positive optical power, a second lens unit having a negative optical power, a third lens unit having a positive optical power, and a fourth lens unit having a negative optical power. At least one of the following conditional formula is fulfilled: 1.1<f1/fT<2.5, where f1 represents the focal length of the first lens unit, and fT represents the focal length of the entirety optical system at the telephoto end, and 0.3<D34W/D34T<2.5 where D34W and D34T represent axial distance between the third lens unit and the fourth lens unit at wide-angle end and telephoto end, respectively.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.