US 11,988,821 B2
Zoom lens and imaging apparatus
Yasutaka Shimada, Saitama (JP); Takuya Tanaka, Saitama (JP); and Takashi Kunugise, Saitama (JP)
Assigned to FUJIFILM Corporation, Tokyo (JP)
Filed by FUJIFILM Corporation, Tokyo (JP)
Filed on Jun. 23, 2021, as Appl. No. 17/355,254.
Claims priority of application No. 2020-112157 (JP), filed on Jun. 29, 2020.
Prior Publication US 2022/0003977 A1, Jan. 6, 2022
Int. Cl. G02B 15/14 (2006.01); G02B 13/00 (2006.01); G02B 13/18 (2006.01); G02B 15/20 (2006.01)
CPC G02B 15/145129 (2019.08) [G02B 13/009 (2013.01); G02B 13/18 (2013.01); G02B 15/20 (2013.01)] 19 Claims
OG exemplary drawing
 
1. A zoom lens consisting of, in order from an object side to an image side:
a first lens group that has a positive refractive power;
a second lens group that has a negative refractive power;
an intermediate lens group that consists of one or two lens groups; and
a final lens group that has a positive refractive power,
wherein during zooming, the second lens group moves along an optical axis, and all distances between adjacent lens groups change,
at least one lens group of the intermediate lens group and the final lens group includes a pair of a positive lens and a negative lens arranged adjacent to each other, and
assuming that an Abbe number of the positive lens based on a d line is νp,
an Abbe number of the negative lens besed on the d lin is νn,
a refractive index of the negative lens at the d line is Nn, and
a temperature coefficient of the refractive index of the negative lens at the d line is 25° C. is (dNn/dT)×10−6, where a unit of dNn/dT is ° C.−1,
Conditional Expressions (1), (2), and (3) are satisfied:
−1.5<dNn/dT<3  (1),
0<Nn+0.0105×νn−2.2188<0.15  (2), and
1.5<νp/νn<2.5  (3).