Title:
VARIABLE MAGNIFICATION OPTICAL ASSEMBLY AND IMAGE CAPTURE DEVICE
Document Type and Number:
WIPO Patent Application WO/2012/124297
Kind Code:
A1
Abstract:
[Problem] To provide a variable magnification optical assembly which is configured to be miniaturized and inexpensive, whereby a strong optical performance is implemented while also having a large aperture ratio, and with which a comparatively medium telephoto variable magnification range is provided. [Solution] A variable magnification optical assembly comprises, in order from the object side: a negative first lens group (G1); an iris which is fixed with respect to the imaging surface when the magnification is changed; and a positive second lens group (G2). When changing the magnification from the wide-angle end to the telephoto end, the gap between the first lens group (G1) and the second lens group (G2) along the optical axis is reduced. The first lens group (G1) further comprises, in order from the object side: a lens (L1) which is a positive lens, with a convex face oriented toward the object side; and two negative lenses (L2), (L3). The variable magnification optical assembly satisfies formula (1), hereinafter, for an Abbe value ν d1 in a d line of the positive lens (L1) of the first lens group (G1): 25.5 <ν d1 < 50 (1)
Inventors:
ONO KAZUNORI (JP)
Application Number:
PCT/JP2012/001597
Publication Date:
September 20, 2012
Filing Date:
March 08, 2012
Export Citation:
Assignee:
FUJIFILM CORP (JP)
ONO KAZUNORI (JP)
ONO KAZUNORI (JP)
International Classes:
G02B15/16; G02B13/18
Foreign References:
| JPH1184237A | 1999-03-26 | |||
| JPH10104514A | 1998-04-24 | |||
| JP2001281543A | 2001-10-10 | |||
| JPH0961711A | 1997-03-07 | |||
| JPS62206517A | 1987-09-11 |
Attorney, Agent or Firm:
YANAGIDA, Masashi et al. (JP)
Seiji Yanagida (JP)
Seiji Yanagida (JP)
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Claims: