Title:
IMAGING LENS OPTICAL SYSTEM
Document Type and Number:
WIPO Patent Application WO/2020/129837
Kind Code:
A1
Abstract:
[Problem] To obtain an imaging lens optical system capable of suppressing focus fluctuation caused by temperature at the time of focusing. [Solution] This imaging lens optical system comprises a first focus lens group (G2) having positive refractive power, and a second focus lens group (G3) having positive refractive power, which are disposed in order from the subject side, wherein an average value A of the temperature coefficients of refractive indexes and a focal length F2 of the first focus lens group (G2), and an average value B of the temperature coefficients of refractive indexes and a focal length F3 of the second focus lens group (G3) satisfy the condition of 0
Inventors:
MOCHIZUKI KEIICHI (JP)
Application Number:
PCT/JP2019/048915
Publication Date:
June 25, 2020
Filing Date:
December 13, 2019
Export Citation:
Assignee:
NITTOH INC (JP)
International Classes:
G02B13/00; G02B13/18; G02B15/20
Domestic Patent References:
| WO2018050174A1 | 2018-03-22 |
Foreign References:
| JP2013033242A | 2013-02-14 | |||
| JP2017219655A | 2017-12-14 | |||
| JP2018132565A | 2018-08-23 | |||
| JP2013120365A | 2013-06-17 | |||
| US20160202452A1 | 2016-07-14 |
Attorney, Agent or Firm:
YANAGIDA, Masashi et al. (JP)
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