Title:
ZOOM LENS FOR PROJECTION AND PROJECTION TYPE DISPLAY DEVICE
Document Type and Number:
WIPO Patent Application WO/2013/061536
Kind Code:
A1
Abstract:
In a zoom lens for projection, the reduction side is made telecentric and has a small size, high versatility and excellent projection performance, while having a high zoom ratio and small F number. In the projection side zoom lens, there are arranged in order from the magnification side: a negative first lens group (G1) that is fixed during zooming; a second lens group (G2) to fifth lens group (G5) that are moved during zooming; and a positive sixth lens group (G6) that is fixed during zooming, and the reduction side is made to be telecentric. During zooming from the wide-angle end to the telephoto end, the second lens group (G2) is moved to the magnification side. From the reduction side of the fifth lens group (G5), the first and second lenses are respectively a positive lens and a negative lens. The sixth lens group (G6) consists in a single positive lens. If the focal point distance of the entire system at the wide-angle end is fw and the focal point distance of the fifth lens group (G5) is f5, the following conditional expression (1) is satisfied. -2.0 < fw/f5 < 0.1 (1)
Inventors:
NAGAHARA AKIKO (JP)
AMANO MASARU (JP)
AMANO MASARU (JP)
Application Number:
PCT/JP2012/006588
Publication Date:
May 02, 2013
Filing Date:
October 15, 2012
Export Citation:
Assignee:
FUJIFILM CORP (JP)
International Classes:
G02B15/20
Foreign References:
| JP2005084455A | 2005-03-31 | |||
| JP2008275713A | 2008-11-13 | |||
| JP2010008797A | 2010-01-14 | |||
| US20090323197A1 | 2009-12-31 | |||
| JP2008304765A | 2008-12-18 |
Attorney, Agent or Firm:
YANAGIDA, Masashi et al. (JP)
Seiji Yanagida (JP)
Seiji Yanagida (JP)
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Claims: