Title:
VARIABLE MAGNIFICATION OPTICAL SYSTEM, OPTICAL DEVICE, AND METHOD FOR MANUFACTURING VARIABLE MAGNIFICATION OPTICAL SYSTEM
Document Type and Number:
WIPO Patent Application WO/2022/172821
Kind Code:
A1
Abstract:
A variable magnification optical system (ZL) comprises: a first lens group (G1) having negative refractive power; and a rear group (GR) including at least one lens group. When changing the magnification, the distance between adjacent lens groups changes. At least one lens group of the rear group (GR) includes a final lens group (GE) having positive refractive power and disposed closest to the image side in the rear group (GR). The variable magnification optical system satisfies the following conditional expression. 0.15 < ft/fGE < 0.60 where ft is the focal length of the variable magnification optical system (ZL) in a telephoto end state, and fGE is the focal length of the final lens group (GE).
Inventors:
OHTAKE FUMIAKI (JP)
SASHIMA TOMOYUKI (JP)
ISHIKAWA TAKAHIRO (JP)
SASHIMA TOMOYUKI (JP)
ISHIKAWA TAKAHIRO (JP)
Application Number:
PCT/JP2022/003964
Publication Date:
August 18, 2022
Filing Date:
February 02, 2022
Export Citation:
Assignee:
NIKON CORP (JP)
International Classes:
G02B15/20; G02B13/18
Domestic Patent References:
| WO2019235471A1 | 2019-12-12 |
Foreign References:
| JP2012173298A | 2012-09-10 | |||
| JP2019191307A | 2019-10-31 | |||
| US20110013071A1 | 2011-01-20 | |||
| JPS56158316A | 1981-12-07 | |||
| JPS5719710A | 1982-02-02 |
Attorney, Agent or Firm:
OHNISHI, Shogo et al. (JP)
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