Title:
ZOOM LENS, OPTICAL DEVICE, AND METHOD FOR VARYING MAGNIFICATION OF ZOOM LENS
Document Type and Number:
WIPO Patent Application WO/2014/136403
Kind Code:
A1
Abstract:
Provided is a zoom lens that comprises a first lens group (G1) having a negative refractive power, a second lens group (G2) having a positive refractive power, and a third lens group (G3) that are arranged in this order from the object side along the optical axis. When varying magnification from a wide-angle end state to a telephoto end state, at least the first lens group (G1) and the second lens group (G2) move so that the interval between the first lens group (G1) and the second lens group (G2) decreases and the interval between the second lens group (G2) and the third lens group (G3) increases, and the following conditional expressions are satisfied: 0.80 < (-f1)/(fw×ft)1/2 < 1.20 and 0.90 < f2/fw < 1.50, wherein f1 is the focal length of the first lens group (G1), fw is the focal length of the zoom lens (ZL) in the wide-angle end state, ft is the local length of the zoom lens (ZL) in the telephoto end state, and f2 is the focal length of the second lens group (G2).
Inventors:
SHIMADA TOSHIYUKI (JP)
Application Number:
PCT/JP2014/001044
Publication Date:
September 12, 2014
Filing Date:
February 27, 2014
Export Citation:
Assignee:
NIKON CORP (JP)
International Classes:
G02B15/163; G02B13/18
Foreign References:
| JP2011175234A | 2011-09-08 | |||
| JP2010085875A | 2010-04-15 | |||
| JP2006178242A | 2006-07-06 | |||
| JP2005084597A | 2005-03-31 | |||
| JPH0862499A | 1996-03-08 | |||
| JPH09258103A | 1997-10-03 | |||
| JP2009237477A | 2009-10-15 | |||
| JP2005156830A | 2005-06-16 | |||
| JP2001042218A | 2001-02-16 | |||
| JPH03240015A | 1991-10-25 | |||
| JP2004318120A | 2004-11-11 | |||
| JP2006113404A | 2006-04-27 |
Attorney, Agent or Firm:
OHNISHI, Shogo et al. (JP)
Shogo Onishi (JP)
Shogo Onishi (JP)
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