Zoom lens and imaging apparatus
AssigneeFUJIFILM Corporation
InventorMasanao Kawana
Life of this patent
Estimating the term…
Abstract
A zoom lens consists of, in order from an object side, a negative first lens group, a positive second lens group, a positive third lens group, a negative fourth lens group, and a positive fifth lens group. The first lens group consists of, in order from the object side, a first A lens group that does not move during focusing, a first B lens group that moves during focusing, and a first C lens group that does not move during focusing. During zooming, the first lens group and the fifth lens group do not move, and the second lens group, the third lens group, and the fourth lens group move. The fourth lens group includes a stop. The zoom lens satisfies a predetermined conditional expression.
Claims20
A zoom lens consisting of, in order from an object side to an image side, a first lens group having a negative refractive power;
- a second lens group having a positive refractive power;
- a third lens group having a positive refractive power;
- a fourth lens group having a negative refractive power;
- and a fifth lens group having a positive refractive power,
- wherein the first lens group consists of, in order from the object side to the image side, a first A lens group that remains stationary with respect to an image surface during focusing, a first B lens group that moves during focusing, and a first C lens group that remains stationary with respect to the image surface during focusing,
- during zooming from a wide angle end to a telephoto end, the first lens group and the fifth lens group remain stationary with respect to the image surface, and the second lens group, the third lens group, and the fourth lens group move along an optical axis by changing a mutual interval,
- the second lens group at the telephoto end is positioned closer to the object side than the second lens group at the wide angle end,
- the third lens group at the telephoto end is positioned closer to the object side than the third lens group at the wide angle end,
- the fourth lens group at the telephoto end is positioned closer to the image side than the fourth lens group at the wide angle end,
- the fourth lens group includes a stop, and
- in a case where a difference in optical axis direction between a position of the second lens group at the telephoto end and a position of the second lens group at the wide angle end is denoted by z2t, and a focal length of the second lens group is denoted by f2, Conditional Expression (1) is satisfied, which is represented by
- 0.05<z2t/f2<0.1 (1).
A zoom lens consisting of, in order from an object side to an image side, a first lens group having a negative refractive power;
- a second lens group having a positive refractive power;
- a third lens group having a positive refractive power;
- a fourth lens group having a negative refractive power;
- and a fifth lens group having a positive refractive power,
- wherein the first lens group consists of a first A lens group that remains stationary with respect to an image surface during focusing, a first B lens group that moves during focusing, and a first C lens group that remains stationary with respect to the image surface during focusing,
- during zooming from a wide angle end to a telephoto end, the first lens group and the fifth lens group remain stationary with respect to the image surface, and the second lens group, the third lens group, and the fourth lens group move along an optical axis by changing a mutual interval,
- the second lens group at the telephoto end is positioned closer to the object side than the second lens group at the wide angle end,
- the third lens group at the telephoto end is positioned closer to the object side than the third lens group at the wide angle end,
- the fourth lens group at the telephoto end is positioned closer to the image side than the fourth lens group at the wide angle end,
- the fourth lens group includes a stop, and
- in a case where a sum of a distance on the optical axis from a lens surface of the first lens group closest to the object side to a lens surface of the fifth lens group closest to the image side, and a back focus of the zoom lens as an air conversion distance is denoted by TL, and a maximum image height is denoted by Y, Conditional Expression (6) is satisfied, which is represented by
- 10<TL/Y<12 (6).
Dependencies are inferred from the claim text.