Zoom lens system and electronic image pickup apparatus using the same
US7719774B2 · kind B2 · utility
Assignee
Inventors
Key dates
| Filing date | Feb 26, 2008 |
| Grant date | May 18, 2010 |
| Priority date | — |
| Expiry date | Nov 12, 2028 |
Classification
- Technology area (CPC G)Physics
- CPC primaryG02B15/145121
- WIPO fieldOptics
- WIPO sectorInstruments
Abstract
In a zoom lens system, at a time of zooming from a wide angle end to a telephoto end, when focused on an object at a longest distance, at the telephoto end, a first lens unit moves to be positioned more toward an object side, than at a wide angle end, at the telephoto end, a second lens unit moves to be positioned more toward an image side, than at the wide angle end, at the telephoto end, an aperture stop and a third lens unit moves to be positioned more toward the object side, than at the wide angle end, and a combined system of the first lens unit and the second lens unit at the wide angle end has a negative refracting power, and at the time of zooming from the wide angle end to the telephoto end, the second lens unit is positioned more toward the object side than a position of the second lens unit at the wide angle end, and the first lens unit moves to be positioned more toward the object side, than at the wide angle end, at the intermediate zoom state, and in the intermediate zoom state, the aperture stop, the third lens unit, and an object point of the third lens unit move to be positioned more toward the object side, than at the wide angle end, and the zoom lens system satis…
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.