Zoom lens, image pickup apparatus including zoom lens, and image pickup system
A zoom lens including, in order from an object side: a first positive lens unit; a second negative lens unit; a third positive lens unit; a fourth negative lens unit; and a fifth positive lens unit, wherein during zooming from a wide angle end, intervals between the adjacent lens units are changed in such a way that the second lens unit is configured to move from the object side to the image side and the third lens unit and the fourth lens unit are configured to move, and a focal length of the third lens unit, a focal length of the fourth lens unit, a movement amount of the second lens unit during zooming from the wide angle end to the telephoto end, and a movement amount of the third lens unit during zooming from the wide angle end to the telephoto end are appropriately set.
1. A zoom lens comprising in order from an object side to an image side:
a first lens unit having a positive refractive power;
a second lens unit having a negative refractive power;
a third lens unit having a positive refractive power;
a fourth lens unit having a negative refractive power; and
a fifth lens unit having a positive refractive power, wherein
during zooming from a wide angle end to a telephoto end, intervals between the adjacent lens units are changed in such a way that the second lens unit is configured to move from the object side to the image side and the third lens unit and the fourth lens unit are configured to move, and
following conditional expressions are satisfied:
−1.52≤ f 3/ f 4≤−1.33;
3.0≤| M 2/ M 3|≤6.0; and
3.9≤| f 1/ f 4|≤5.0, where
f3 represents a focal length of the third lens unit, f4 represents a focal length of the fourth lens unit, M2 represents a movement amount of the second lens unit during zooming from the wide angle end to the telephoto end, M3 represents a movement amount of the third lens unit during zooming from the wide angle end to the telephoto end, and f1 represents a focal length of the first lens unit.
2. The zoom lens according to claim 1 , wherein the first lens unit is not configured to move for zooming.
3. The zoom lens according to claim 1 , wherein the fifth lens unit is not configured to move for zooming.
4. The zoom lens according to claim 1 , wherein an aperture stop is arranged between the second lens unit and the third lens unit, and the aperture stop is not configured to move for zooming.
5. The zoom lens according to claim 1 , wherein the first lens unit consists of a negative lens, a positive lens, and a positive lens arranged in the order from the object side to the image side.
6. The zoom lens according to claim 1 , wherein the fourth lens unit consists of a single negative lens.
7. The zoom lens according to claim 1 , wherein the fourth lens unit consists of a positive lens and a negative lens cemented together.
8. The zoom lens according to claim 1 , wherein the fifth lens unit consists of a single positive lens.
9. The zoom lens according to claim 1 , wherein the fifth lens unit consists of a positive lens and a negative lens cemented together.
10. The zoom lens according to claim 1 , wherein a following conditional expression is satisfied:
2.0≤ f 1/ f 3≤4.0, where
f1 represents a focal length of the first lens unit.
11. The zoom lens according to claim 1 , wherein a following conditional expression is satisfied:
6.0≤ f 1/ fw≤ 12.0, where
fw represents a focal length of the zoom lens at the wide angle end.
12. The zoom lens according to claim 1 , wherein a following conditional expression is satisfied:
2.0≤ f 3/ fw≤ 4.0, where
fw represents a focal length of the zoom lens at the wide angle end.
13. The zoom lens according to claim 1 , wherein a following conditional expression is satisfied:
1.0≤| f 4/ fw|≤ 3.0, where
fw represents a focal length of the zoom lens at the wide angle end.
14. The zoom lens according to claim 1 , wherein a following conditional expression is satisfied:
0.2≤| M 4/ M 3|≤2.0, where
M4 represents a movement amount of the fourth lens unit during zooming from the wide angle end to the telephoto end.
15. The zoom lens according to claim 1 , wherein a following conditional expression is satisfied:
1.1≤|(β3 T×β 4 T )/(β3 W×β 4 W )|≤2.0, where
β3W represents lateral magnification of the third lens unit at the wide angle end, β3T represents lateral magnification of the third lens unit at the telephoto end, β4W represents lateral magnification of the fourth lens unit at the wide angle end, and β4T represents lateral magnification of the fourth lens unit at the telephoto end.
16. The zoom lens according to claim 1 , wherein a following conditional expression is satisfied:
−2.5≤ f 3/ f 2≤−1.0, where
f2 represents a focal length of the second lens unit.
17. The zoom lens according to claim 1 , wherein a following conditional expression is satisfied:
0.5≤ f 3/ f 5≤2.0, where
f5 represents a focal length of the fifth lens unit.
18. The zoom lens according to claim 1 , wherein during zooming from the wide angle end to the telephoto end, the third lens unit is configured to move to the object side, and the fourth lens unit is configured to move to the object side.
19. An image pickup apparatus comprising:
a zoom lens comprising, in order from an object side to an image side:
a first lens unit having a positive refractive power;
a second lens unit having a negative refractive power;
a third lens unit having a positive refractive power;
a fourth lens unit having a negative refractive power; and
a fifth lens unit having a positive refractive power, wherein
during zooming from a wide angle end to a telephoto end, intervals between the adjacent lens units are changed in such a way that the second lens unit is configured to move from the object side to the image side and the third lens unit and the fourth lens unit are configured to move, and following conditional expressions are satisfied:
−1.52≤ f 3/ f 4≤−1.33;
3.0≤| M 2/ M 3|≤6.0; and
3.9≤| f 1/ f 4|≤5.0, where
f3 represents a focal length of the third lens unit, f4 represents a focal length of the fourth lens unit, M2 represents a movement amount of the second lens unit during zooming from the wide angle end to the telephoto end, M3 represents a movement amount of the third lens unit during zooming from the wide angle end to the telephoto end, and f1 represents a focal length of the first lens unit; and
an image pickup element configured to receive an image formed by the zoom lens.
20. An image pickup system comprising:
a zoom lens comprising in order from an object side to an image side:
a first lens unit having a positive refractive power;
a second lens unit having a negative refractive power;
a third lens unit having a positive refractive power;
a fourth lens unit having a negative refractive power; and
a fifth lens unit having a positive refractive power, wherein
during zooming from a wide angle end to a telephoto end, intervals between the adjacent lens units are changed in such a way that the second lens unit is configured to move from the object side to the image side and the third lens unit and the fourth lens unit are configured to move, and following conditional expressions are satisfied:
−1.52≤ f 3/ f 4≤−1.33;
3.0≤| M 2/ M 3|≤6.0; and
3.9≤| f 1/ f 4|≤5.0, where
f3 represents a focal length of the third lens unit, f4 represents a focal length of the fourth lens unit, M2 represents a movement amount of the second lens unit during zooming from the wide angle end to the telephoto end, M3 represents a movement amount of the third lens unit during zooming from the wide angle end to the telephoto end, and f1 represents a focal length of the first lens unit; and
a control unit configured to control the zoom lens during zooming.