Back to results
US 12,613,397 B2Granted
Imaging lens and imaging apparatus
AssigneeFUJIFILM Corporation
InventorsYasutaka Shimada, Shunsuke Miyagishima
Life of this patent
Estimating the term…
Abstract
The imaging lens includes, in order from an object side, a first lens group that has a refractive power, a second lens group that has a positive refractive power, and a third lens group that has a negative refractive power. During focusing, the second lens group moves. The second lens group includes a stop and at least three negative lenses. The imaging lens satisfies predetermined conditional expressions.
Claims18
An imaging lens consisting of, in order from an object side to an image side:
- a first lens group that has a refractive power;
- a second lens group that has a positive refractive power;
- and a third lens group that has a negative refractive power,
- wherein during focusing, the first lens group and the third lens group remain stationary with respect to an image plane, and the second lens group moves along an optical axis,
- the second lens group includes a stop and at least three negative lenses,
- a sum of a distance on the optical axis from a lens surface closest to the object side in the first lens group to a lens surface closest to the image side in the third lens group and a back focal length of the imaging lens in terms of an air-equivalent distance is TTL,
- a focal length of the imaging lens in a state in which an infinite distance object is in focus is f,
- a maximum half angle of view in a state in which the infinite distance object is in focus is ωm, and
- Conditional Expression (1) is satisfied, which is represented by
- 5<TTL2/(f2×tan ωm)<15 (1),
- wherein
- a focal length of the first lens group is f1,
- a focal length of the third lens group is f3, and
- Conditional Expression (6) is satisfied, which is represented by
- 1.5<f3/f1<3.5 (6).
12 more elements
Dependencies are inferred from the claim text.