Zoom lens, optical apparatus, and a manufacturing method of the zoom lens
AssigneeNikon Corporation
InventorKeigo KOIDA
Life of this patent
Estimating the term…
Abstract
A zoom lens includes, in order from an object, a first lens group having a negative refractive power, a second lens group having a positive refractive power, a third lens group having a negative refractive power, and a fourth lens group. Zooming is performed by changing respective distances between the first and second lens groups, the second and third lens groups, and the third and fourth lens groups. The first lens group includes a negative lens disposed closest to the object, and a negative lens. Specified conditional expressions are satisfied.
Claims2
1-17. (canceled)
A zoom lens comprising, in order from an object, a first lens group having a negative refractive power, a second lens group having a positive refractive power, a third lens group having a negative refractive power, and a fourth lens group having a positive refractive power,
- the first lens group, the second lens group, the third lens group, and the fourth lens group moving on an optical axis so that zooming is performed by changing respective distances between the first lens group and the second lens group, the second lens group and the third lens group, and the third lens group and the fourth lens group,
- the first lens group comprising a negative lens disposed closest to the object, a negative lens, and a positive lens,
- the third lens group consisting of one negative lens,
- the fourth lens group consisting of one lens, and
- the following conditional expressions being satisfied:
- 0.3
- <
- D
-
- 3
-
- W
- /
- D
-
- 3
-
- T
- <
- 1.1
- 2.3
- <
- f
-
- 4
- /
- fw
- <
- 8.
- where D3W denotes an air interval between the third lens group and the fourth lens group in a wide-angle end state,
- D3T denotes an air interval between the third lens group and the fourth lens group in a telephoto end state,
- f4 denotes a focal length of the fourth lens group, and
- fw denotes a focal length of the zoom lens in the wide-angle end state.
Dependencies are inferred from the claim text.