Title:
PROJECTION ZOOM LENS AND PROJECTION DISPLAY DEVICE
Document Type and Number:
WIPO Patent Application WO/2014/076925
Kind Code:
A1
Abstract:
[Problem] To provide a projection zoom lens with a high magnification ratio and make the numerical aperture thereof constant across the entire magnification range. [Solution] This projection zoom lens comprises the following, in order from the enlargement side: a negative first lens group (G1); positive second through fourth lens groups (G2, G3, G4) that move while zooming; a fifth lens group (G5) that moves while zooming; and a positive sixth lens group (G6). Said projection zoom lens is designed such that the reduction side is telecentric and the numerical aperture of the zoom lens is constant across the entire magnification range. The fourth lens group (G4) moves more than any of the other lens groups when zooming from the wide-angle end to the telephoto end, and the absolute value (mk) of the amount that the kth lens group moves when zooming from the wide-angle end to the telephoto end for each k from 2 to 5 and the focal length (fw) of the entire system at the wide-angle end satisfy relations (1) and (2). (1) 1.9 < m4/fw (2) 0.7 < (m3+m4)/(m2+m3+m4+m5)
Inventors:
KAWANA MASANAO (JP)
AMANO MASARU (JP)
NAGATOSHI YUKIKO (JP)
AMANO MASARU (JP)
NAGATOSHI YUKIKO (JP)
Application Number:
PCT/JP2013/006615
Publication Date:
May 22, 2014
Filing Date:
November 11, 2013
Export Citation:
Assignee:
FUJIFILM CORP (JP)
International Classes:
G02B15/20; G02B13/18
Foreign References:
| JP2007256424A | 2007-10-04 | |||
| JP2007206420A | 2007-08-16 | |||
| JP2005292260A | 2005-10-20 | |||
| JP2008242402A | 2008-10-09 | |||
| JP2008046259A | 2008-02-28 |
Attorney, Agent or Firm:
YANAGIDA, Masashi et al. (JP)
Seiji Yanagida (JP)
Seiji Yanagida (JP)
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