Title:
VARIABLE MAGNIFICATION OPTICAL SYSTEM, OPTICAL APPARATUS, AND METHOD FOR MANUFACTURING VARIABLE MAGNIFICATION OPTICAL SYSTEM
Document Type and Number:
WIPO Patent Application WO/2021/153221
Kind Code:
A1
Abstract:
A variable magnification optical system used in an optical apparatus such as a camera 1 is configured to comprise a plurality of lens groups, the respective distances between the plurality of lens groups changing when the magnification is changed. The variable magnification optical system is configured to have at least one lens surface having a pole in a final lens group closest to the image side among the plurality of lens groups, and satisfy conditional expression (1) or conditional expression (2) shown below. (1): 0.50 < TL/fw < 10.00 where TL is the shorter of the optical total length in the wide-angle end state and the optical total length in the telephoto end state of the variable magnification optical system, and fw is the focal length of the variable magnification optical system in the wide-angle end state. (2): -5.00 < fRI/fR < 5.00 where fRI is the focal length of the lens having the lens surface having the pole in the final lens group, and fR is the focal length of the final lens group.
Inventors:
MACHIDA KOSUKE (JP)
TOKUNAGA KYOYA (JP)
TOKUNAGA KYOYA (JP)
Application Number:
PCT/JP2021/000728
Publication Date:
August 05, 2021
Filing Date:
January 12, 2021
Export Citation:
Assignee:
NIKON CORP (JP)
International Classes:
G02B15/20; G02B13/18
Foreign References:
| JP2013130676A | 2013-07-04 | |||
| JPH1152242A | 1999-02-26 | |||
| JP2011128364A | 2011-06-30 | |||
| JP2002372667A | 2002-12-26 | |||
| JP2001124990A | 2001-05-11 | |||
| JP2011123210A | 2011-06-23 |
Attorney, Agent or Firm:
AOKI, Atsushi et al. (JP)
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