Imaging lens and imaging apparatus
AssigneeFUJIFILM Corporation
InventorsRyoko Tomioka, Daiki Kawamura
Life of this patent
Estimating the term…
Abstract
The imaging lens consists of a positive first lens group remaining stationary during focusing, a negative second lens group, a positive third lens group, and a negative fourth lens group remaining stationary during focusing, in order from an object side. During focusing from the infinite object to the closest object, the second lens group moves to an image side, the third lens group moves to the object side, and the fourth lens group consists of a fourth-a lens group which is a vibration-proof lens group and a fourth-b lens group, in order from the object side. In the imaging lens, predetermined conditional expressions are satisfied.
Claims19
An imaging lens comprising, in order from an object side:
- a first lens group having a positive refractive power;
- a second lens group having a negative refractive power;
- a third lens group having a positive refractive power;
- and
- a fourth lens group having a negative refractive power,
- wherein during focusing from an infinite object to a closest object, the first lens group remains stationary with respect to an image plane, the second lens group moves to an image side, the third lens group moves to the object side, and the fourth lens group remains stationary with respect to the image plane,
- the fourth lens group consists of a fourth-a lens group and a fourth-b lens group in order from the object side, and corrects blurring of an image on the image plane by moving the fourth-a lens group in a direction perpendicular to an optical axis, and
- in a case where a focal length of the fourth-a lens group is set to f4a, and a focal length of the whole system during focusing of the infinite object is set to f, the following Conditional Expression (1) is satisfied;
- 0.25<|f4a/f|<0.45 (1).
Dependencies are inferred from the claim text.