Title:
VARIABLE MAGNIFICATION OPTICAL SYSTEM, OPTICAL DEVICE, AND METHOD FOR PRODUCING VARIABLE MAGNIFICATION OPTICAL SYSTEM
Document Type and Number:
WIPO Patent Application WO/2016/104785
Kind Code:
A1
Abstract:
This variable magnification optical system has a first lens group (G1) that is disposed furthest to an object side and has a positive refractive power, a negative lens group (G2) that is disposed further to an image side than the first lens group and has a negative refractive power, and a focusing group (G3) that is disposed between the negative lens group and an aperture stop, wherein: when magnification is varied, the space between the first lens group and the negative lens group changes, and the space between the negative lens group and the stop changes; during focusing, the space between the focusing group and a lens that is disposed in a position facing the object side of the focusing group changes, and the space between the focusing group and a lens that is disposed in a position facing the image side of the focusing group changes; and the focusing group comprises one single lens having a positive refractive power and satisfies a prescribed conditional expression.
Inventors:
YAMAMOTO HIROSHI (JP)
MATSUO TAKU (JP)
OBAMA AKIHIKO (JP)
UCHIDA KENSUKE (JP)
MATSUO TAKU (JP)
OBAMA AKIHIKO (JP)
UCHIDA KENSUKE (JP)
Application Number:
PCT/JP2015/086407
Publication Date:
June 30, 2016
Filing Date:
December 25, 2015
Export Citation:
Assignee:
NIKON CORP (JP)
International Classes:
G02B15/20
Domestic Patent References:
| WO2013146758A1 | 2013-10-03 |
Foreign References:
| JP2014126766A | 2014-07-07 | |||
| JP2001033698A | 2001-02-09 | |||
| JPH07113955A | 1995-05-02 |
Attorney, Agent or Firm:
SHIGA Masatake et al. (JP)
Masatake Shiga (JP)
Masatake Shiga (JP)
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