IP Library Granted Patent US 9,798,120
Granted Patent B2
US 9,798,120 · App. 14/843,481 · Granted Oct 24, 2017

Zoom lens and image pickup apparatus using the same

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Quick Facts
Patent No.
US 9,798,120
App. No.
14/843,481
Granted
Oct 24, 2017
Kind
B2
Abstract

A zoom lens includes 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, and a fourth lens unit having a negative refractive power, and includes an aperture stop which is disposed between the second lens unit and the fourth lens unit, and the first lens unit includes a negative lens and a plurality of positive lenses, and at the time of zooming from a wide angle end to a telephoto end, a distance between the first lens unit and the second lens unit widens, a distance between the second lens unit and the third lens unit narrows, and a distance between the third lens unit and the fourth lens unit changes, and the zoom lens satisfies predetermined conditional expressions.

Claims (364)

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;

an image-side lens unit having a positive refractive power; and

an aperture stop which is disposed between the second lens unit and the fourth lens unit,

wherein the first lens unit includes a negative lens and a plurality of positive lenses,

at the time of zooming from a wide angle end to a telephoto end, a distance between the first lens unit and the second lens unit widens, a distance between the second lens unit and the third lens unit narrows, and a distance between the third lens unit and the fourth lens unit changes, and

the following conditional expressions (4-1) and (5) are satisfied:

0.05<( D G1IMt −D G1IMw )/ f t ≦0.192  (4-1)

20< f t /f w <50  (5)

where D G1IMt denotes a distance on the optical axis from an object-side surface of a lens nearest to the object side in the first lens unit up to the image, at the telephoto end,

D G1IMw denotes a distance on the optical axis from the object-side surface of a lens nearest to the object side in the first lens unit up to the image, at the wide angle end,

f t denotes a focal length of the overall zoom lens system at the telephoto end, and

f w denotes a focal length of the overall zoom lens system at the wide angle end, wherein

the number of lens elements in the first lens unit is three,

the following conditional expression (6) is satisfied

−0.06< f G2 /f t <−0.03  (6)

where f G2 denotes a focal length of the second lens unit.

2. The zoom lens according to claim 1 , wherein

the first lens unit includes, in order from an object side to an image side, a cemented lens includes a negative lens and a positive lenses, and a positive lens.

3. The zoom lens according to claim 1 , wherein

the following conditional expression (2) is satisfied

0.2< D ASIMt /f t <0.40  (2)

where D ASIMt denotes a distance on the optical axis from the aperture stop up to an image, at the telephoto end.

4. 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;

an image-side lens unit having a positive refractive power; and

an aperture stop which is disposed between the second lens unit and the fourth lens unit,

wherein the first lens unit includes a negative lens and a plurality of positive lenses,

at the time of zooming from a wide angle end to a telephoto end, a distance between the first lens unit and the second lens unit widens, a distance between the second lens unit and the third lens unit narrows, and a distance between the third lens unit and the fourth lens unit changes, and

the following conditional expressions (4-1) and (5) are satisfied:

0.05<( D G1IMt −D G1IMw )/ f t ≦0.192  (4-1)

20< f t /f w <50  (5)

where D G1IMt denotes a distance on the optical axis from an object-side surface of a lens nearest to the object side in the first lens unit up to the image, at the telephoto end,

D G1IMw denotes a distance on the optical axis from the object-side surface of a lens nearest to the object side in the first lens unit up to the image, at the wide angle end,

f t denotes a focal length of the overall zoom lens system at the telephoto end, and

f w denotes a focal length of the overall zoom lens system at the wide angle end, wherein

the number of lens elements in the second lens unit is three,

the following conditional expression (6) is satisfied

−0.06< f G2 /f t <−0.03  (6)

where f G2 denotes a focal length of the second lens unit.

5. The zoom lens according to claim 4 , wherein

the second lens unit includes, in order from an object side to an image side, a negative lens, a negative lens and a positive lenses.

6. The zoom lens according to claim 4 , wherein

the following conditional expression (2) is satisfied

0.2< D ASIMt /f t <0.40  (2)

where D ASIMt denotes a distance on the optical axis from the aperture stop up to an image, at the telephoto end.

7. 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;

an image-side lens unit having a positive refractive power; and

an aperture stop which is disposed between the second lens unit and the fourth lens unit,

wherein the first lens unit includes a negative lens and a plurality of positive lenses,

at the time of zooming from a wide angle end to a telephoto end, a distance between the first lens unit and the second lens unit widens, a distance between the second lens unit and the third lens unit narrows, and a distance between the third lens unit and the fourth lens unit changes, and

the following conditional expressions (4-1) and (5) are satisfied:

0.05<( D G1IMt −D G1IMw )/ f t ≦0.192  (4-1)

20< f t /f w <50  (5)

where D G1IMt denotes a distance on the optical axis from an object-side surface of a lens nearest to the object side in the first lens unit up to the image, at the telephoto end,

D G1IMw denotes a distance on the optical axis from the object-side surface of a lens nearest to the object side in the first lens unit up to the image, at the wide angle end,

f t denotes a focal length of the overall zoom lens system at the telephoto end, and

f w denotes a focal length of the overall zoom lens system at the wide angle end, wherein

the number of lens elements in the third lens unit is three,

the following conditional expression (6) is satisfied

−0.06< f G2 /f t <−0.03  (6)

where f G2 denotes a focal length of the second lens unit.

8. The zoom lens according to claim 7 , wherein

the third lens unit includes, in order from an object side to an image side, a positive lens, a negative lens and a positive lenses.

9. The zoom lens according to claim 7 , wherein

the following conditional expression (2) is satisfied

0.2< D ASIMt /f t <0.40  (2)

where D ASIMt denotes a distance on the optical axis from the aperture stop up to an image, at the telephoto end.

10. 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;

an image-side lens unit having a positive refractive power; and

an aperture stop which is disposed between the second lens unit and the fourth lens unit,

wherein the first lens unit includes a negative lens and a plurality of positive lenses,

at the time of zooming from a wide angle end to a telephoto end, a distance between the first lens unit and the second lens unit widens, a distance between the second lens unit and the third lens unit narrows, and a distance between the third lens unit and the fourth lens unit changes, and

the following conditional expressions (4-1) and (5) are satisfied:

0.05<( D G1IMt −D G1IMw )/ f t ≦0.192  (4-1)

20< f t /f w <50  (5)

where D G1IMt denotes a distance on the optical axis from an object-side surface of a lens nearest to the object side in the first lens unit up to the image, at the telephoto end,

D G1IMw denotes a distance on the optical axis from the object-side surface of a lens nearest to the object side in the first lens unit up to the image, at the wide angle end,

f t denotes a focal length of the overall zoom lens system at the telephoto end, and

f w denotes a focal length of the overall zoom lens system at the wide angle end, wherein

the number of lens elements in the first lens unit is three,

the number of lens elements in the second lens unit is three,

the number of lens elements in the third lens unit is three,

the following conditional expression (6) is satisfied

−0.06< f G2 /f t <−0.03  (6)

where f G2 denotes a focal length of the second lens unit,

the lens component is a lens of which, only two surfaces namely, an object-side surface and an image-side surface make a contact with air, in an optical path.

11. The zoom lens according to claim 10 , wherein

the fourth lens unit consists of one lens component, and

the lens component is a lens of which, only two surfaces namely, an object-side surface and an image-side surface make a contact with air, in an optical path.

12. The zoom lens according to claim 10 , wherein

the image-side lens unit consists of one lens component, and

the lens component is a lens of which, only two surfaces namely, an object-side surface and an image-side surface make a contact with air, in an optical path.

13. The zoom lens according to claim 10 , wherein

the fourth lens unit consists of one lens component,

the image-side lens unit includes one lens component, and

the lens component is a lens of which, only two surfaces namely, an object-side surface and an image-side surface make a contact with air, in an optical path.

14. The zoom lens according to claim 13 , wherein

the following conditional expression (2) is satisfied

0.2< D ASIMt /f t <0.40  (2)

where D ASIMt denotes a distance on the optical axis from the aperture stop up to an image, at the telephoto end.

15. 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;

an image-side lens unit having a positive refractive power; and

an aperture stop which is disposed between the second lens unit and the fourth lens unit,

wherein the first lens unit includes a negative lens and a plurality of positive lenses,

at the time of zooming from a wide angle end to a telephoto end, a distance between the first lens unit and the second lens unit widens, a distance between the second lens unit and the third lens unit narrows, and a distance between the third lens unit and the fourth lens unit changes, and

the following conditional expressions (4) and (5) are satisfied:

0.05<( D G1IMt −D G1IMw )/ f t <0.22  (4)

20< f t /f w <50  (5)

where D G1IMt denotes a distance on the optical axis from an object-side surface of a lens nearest to the object side in the first lens unit up to the image, at the telephoto end,

D G1IMw denotes a distance on the optical axis from the object-side surface of a lens nearest to the object side in the first lens unit up to the image, at the wide angle end,

f t denotes a focal length of the overall zoom lens system at the telephoto end, and

f w denotes a focal length of the overall zoom lens system at the wide angle end, wherein

the following conditional expression (2) is satisfied

0.2< D ASIMt /f t <0.40  (2)

where D ASIMt denotes a distance on the optical axis from the aperture stop up to an image, at the telephoto end.

16. 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;

an image-side lens unit having a positive refractive power; and

an aperture stop which is disposed between the second lens unit and the fourth lens unit,

wherein the first lens unit includes a negative lens and a plurality of positive lenses,

at the time of zooming from a wide angle end to a telephoto end, a distance between the first lens unit and the second lens unit widens, a distance between the second lens unit and the third lens unit narrows, and a distance between the third lens unit and the fourth lens unit changes, and

the following conditional expressions (4) and (5-1) are satisfied:

0.05<( D G1IMt −D G1IMw )/ f t <0.22  (4)

23.067≦ f t /f w <50  (5-1)

where D G1IMt denotes a distance on the optical axis from an object-side surface of a lens nearest to the object side in the first lens unit up to the image, at the telephoto end,

D G1IMw denotes a distance on the optical axis from the object-side surface of a lens nearest to the object side in the first lens unit up to the image, at the wide angle end,

f t denotes a focal length of the overall zoom lens system at the telephoto end, and

f w denotes a focal length of the overall zoom lens system at the wide angle end, wherein

the number of lens elements in the first lens unit is three,

the following conditional expression (6) is satisfied

−0.06< f G2 /f t <−0.03  (6)

where f G2 denotes a focal length of the second lens unit.

17. The zoom lens according to claim 16 , wherein

the first lens unit includes, in order from an object side to an image side, a cemented lens includes a negative lens and a positive lenses, and a positive lens.

18. The zoom lens according to claim 16 , wherein

the following conditional expression (2) is satisfied

0.2< D ASIMt /f t <0.40  (2)

where D ASIMt denotes a distance on the optical axis from the aperture stop up to an image, at the telephoto end.

19. 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;

an image-side lens unit having a positive refractive power; and

an aperture stop which is disposed between the second lens unit and the fourth lens unit,

wherein the first lens unit includes a negative lens and a plurality of positive lenses,

at the time of zooming from a wide angle end to a telephoto end, a distance between the first lens unit and the second lens unit widens, a distance between the second lens unit and the third lens unit narrows, and a distance between the third lens unit and the fourth lens unit changes, and

the following conditional expressions (4) and (5-1) are satisfied:

0.05<( D G1IMt −D G1IMw )/ f t <0.22  (4)

23.067≦ f t /f w <50  (5-1)

where D G1IMt denotes a distance on the optical axis from an object-side surface of a lens nearest to the object side in the first lens unit up to the image, at the telephoto end,

D G1IMw denotes a distance on the optical axis from the object-side surface of a lens nearest to the object side in the first lens unit up to the image, at the wide angle end,

f t denotes a focal length of the overall zoom lens system at the telephoto end, and

f w denotes a focal length of the overall zoom lens system at the wide angle end, wherein

the number of lens elements in the second lens unit is three,

the following conditional expression (6) is satisfied

−0.06< f G2 /f t <−0.03  (6)

where f G2 denotes a focal length of the second lens unit.

20. The zoom lens according to claim 19 , wherein

the second lens unit includes, in order from an object side to an image side, a negative lens, a negative lens and a positive lenses.

21. The zoom lens according to claim 19 , wherein

the following conditional expression (2) is satisfied

0.2< D ASIMt /f t <0.40  (2)

where D ASIMt denotes a distance on the optical axis from the aperture stop up to an image, at the telephoto end.

22. 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;

an image-side lens unit having a positive refractive power; and

an aperture stop which is disposed between the second lens unit and the fourth lens unit,

wherein the first lens unit includes a negative lens and a plurality of positive lenses,

at the time of zooming from a wide angle end to a telephoto end, a distance between the first lens unit and the second lens unit widens, a distance between the second lens unit and the third lens unit narrows, and a distance between the third lens unit and the fourth lens unit changes, and

the following conditional expressions (4) and (5-1) are satisfied:

0.05<( D G1IMt −D G1IMw )/ f t <0.22  (4)

23.067≦ f t /f w <50  (5-1)

where D G1IMt denotes a distance on the optical axis from an object-side surface of a lens nearest to the object side in the first lens unit up to the image, at the telephoto end,

D G1IMw denotes a distance on the optical axis from the object-side surface of a lens nearest to the object side in the first lens unit up to the image, at the wide angle end,

f t denotes a focal length of the overall zoom lens system at the telephoto end, and

f w denotes a focal length of the overall zoom lens system at the wide angle end, wherein

the number of lens elements in the third lens unit is three,

the following conditional expression (6) is satisfied

−0.06< f G2 /f t <−0.03  (6)

where f G2 denotes a focal length of the second lens unit.

23. The zoom lens according to claim 22 , wherein

the third lens unit includes, in order from an object side to an image side, a positive lens, a negative lens and a positive lenses.

24. The zoom lens according to claim 22 , wherein

the following conditional expression (2) is satisfied

0.2< D ASIMt /f t <0.40  (2)

where D ASIMt denotes a distance on the optical axis from the aperture stop up to an image, at the telephoto end.

25. 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;

an image-side lens unit having a positive refractive power; and

an aperture stop which is disposed between the second lens unit and the fourth lens unit,

wherein the first lens unit includes a negative lens and a plurality of positive lenses,

at the time of zooming from a wide angle end to a telephoto end, a distance between the first lens unit and the second lens unit widens, a distance between the second lens unit and the third lens unit narrows, and a distance between the third lens unit and the fourth lens unit changes, and

the following conditional expressions (4) and (5-1) are satisfied:

0.05<( D G1IMt −D G1IMw )/ f t <0.22  (4)

23.067≦ f t /f w <50  (5-1)

where D G1IMt denotes a distance on the optical axis from an object-side surface of a lens nearest to the object side in the first lens unit up to the image, at the telephoto end,

D G1IMw denotes a distance on the optical axis from the object-side surface of a lens nearest to the object side in the first lens unit up to the image, at the wide angle end,

f t denotes a focal length of the overall zoom lens system at the telephoto end, and

f w denotes a focal length of the overall zoom lens system at the wide angle end, wherein

the number of lens elements in the first lens unit is three,

the number of lens elements in the second lens unit is three,

the number of lens elements in the third lens unit is three,

the following conditional expression (6) is satisfied

−0.06< f G2 /f t <−0.03  (6)

where f G2 denotes a focal length of the second lens unit;

the lens component is a lens of which, only two surfaces namely, an object-side surface and an image-side surface make a contact with air, in an optical path.

26. The zoom lens according to claim 25 , wherein

the fourth lens unit consists of one lens component, and

the lens component is a lens of which, only two surfaces namely, an object-side surface and an image-side surface make a contact with air, in an optical path.

27. The zoom lens according to claim 25 , wherein

the image-side lens unit consists of one lens component, and

the lens component is a lens of which, only two surfaces namely, an object-side surface and an image-side surface make a contact with air, in an optical path.

28. The zoom lens according to claim 25 , wherein

the fourth lens unit consists of one lens component,

the image-side lens unit consists of one lens component, and

the lens component is a lens of which, only two surfaces namely, an object-side surface and an image-side surface make a contact with air, in an optical path.

29. The zoom lens according to claim 28 , wherein

the following conditional expression (2) is satisfied

0.2< D ASIMt /f t <0.40  (2)

where D ASIMt denotes a distance on the optical axis from the aperture stop up to an image, at the telephoto end.

30. 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;

an image-side lens unit having a positive refractive power; and

an aperture stop which is disposed between the second lens unit and the fourth lens unit,

wherein the first lens unit includes a negative lens and a plurality of positive lenses,

at the time of zooming from a wide angle end to a telephoto end, a distance between the first lens unit and the second lens unit widens, a distance between the second lens unit and the third lens unit narrows, and a distance between the third lens unit and the fourth lens unit changes, and

the following conditional expressions (4) and (5) are satisfied:

0.05<( D G1IMt −D G1IMw )/ f t <0.22  (4)

20< f t /f w <50  (5)

where D G1IMt denotes a distance on the optical axis from an object-side surface of a lens nearest to the object side in the first lens unit up to the image, at the telephoto end,

D G1IMw denotes a distance on the optical axis from the object-side surface of a lens nearest to the object side in the first lens unit up to the image, at the wide angle end,

f t denotes a focal length of the overall zoom lens system at the telephoto end, and

f w denotes a focal length of the overall zoom lens system at the wide angle end, wherein

the number of lens elements in the first lens unit is three,

the following conditional expression (6-1) is satisfied

−0.056≦ f G2 /f t <−0.03  (6-1)

where f G2 denotes a focal length of the second lens unit.

31. The zoom lens according to claim 30 , wherein

the first lens unit includes, in order from an object side to an image side, a cemented lens includes a negative lens and a positive lenses, and a positive lens.

32. The zoom lens according to claim 30 , wherein

the following conditional expression (2) is satisfied

0.2< D ASIMt /f t <0.40  (2)

where D ASIMt denotes a distance on the optical axis from the aperture stop up to an image, at the telephoto end.

33. 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;

an image-side lens unit having a positive refractive power; and

an aperture stop which is disposed between the second lens unit and the fourth lens unit,

wherein the first lens unit includes a negative lens and a plurality of positive lenses,

at the time of zooming from a wide angle end to a telephoto end, a distance between the first lens unit and the second lens unit widens, a distance between the second lens unit and the third lens unit narrows, and a distance between the third lens unit and the fourth lens unit changes, and

the following conditional expressions (4) and (5) are satisfied:

0.05<( D G1IMt −D G1IMw )/ f t <0.22  (4)

20< f t /f w <50  (5)

where D G1IMt denotes a distance on the optical axis from an object-side surface of a lens nearest to the object side in the first lens unit up to the image, at the telephoto end,

D G1IMw denotes a distance on the optical axis from the object-side surface of a lens nearest to the object side in the first lens unit up to the image, at the wide angle end,

f t denotes a focal length of the overall zoom lens system at the telephoto end, and

f w denotes a focal length of the overall zoom lens system at the wide angle end, wherein

the number of lens elements in the second lens unit is three,

the following conditional expression (6-1) is satisfied

−0.056≦ f G2 /f t <−0.03  (6-1)

where f G2 denotes a focal length of the second lens unit.

34. The zoom lens according to claim 33 , wherein

the second lens unit includes, in order from an object side to an image side, a negative lens, a negative lens and a positive lenses.

35. The zoom lens according to claim 33 , wherein

the following conditional expression (2) is satisfied

0.2< D ASIMt /f t <0.40  (2)

where D ASIMt denotes a distance on the optical axis from the aperture stop up to an image, at the telephoto end.

36. 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;

an image-side lens unit having a positive refractive power; and

an aperture stop which is disposed between the second lens unit and the fourth lens unit,

wherein the first lens unit includes a negative lens and a plurality of positive lenses,

at the time of zooming from a wide angle end to a telephoto end, a distance between the first lens unit and the second lens unit widens, a distance between the second lens unit and the third lens unit narrows, and a distance between the third lens unit and the fourth lens unit changes, and

the following conditional expressions (4) and (5) are satisfied:

0.05<( D G1IMt −D G1IMw )/ f t <0.22  (4)

20< f t /f w <50  (5)

where D G1IMt denotes a distance on the optical axis from an object-side surface of a lens nearest to the object side in the first lens unit up to the image, at the telephoto end,

D G1IMw denotes a distance on the optical axis from the object-side surface of a lens nearest to the object side in the first lens unit up to the image, at the wide angle end,

f t denotes a focal length of the overall zoom lens system at the telephoto end, and

f w denotes a focal length of the overall zoom lens system at the wide angle end, wherein

the number of lens elements in the third lens unit is three,

the following conditional expression (6-1) is satisfied

−0.056≦ f G2 /f t <−0.03  (6-1)

where f G2 denotes a focal length of the second lens unit.

37. The zoom lens according to claim 36 , wherein

the third lens unit includes, in order from an object side to an image side, a positive lens, a negative lens and a positive lenses.

38. The zoom lens according to claim 36 , wherein

the following conditional expression (2) is satisfied

0.2< D ASIMt /f t <0.40  (2)

where D ASIMt denotes a distance on the optical axis from the aperture stop up to an image, at the telephoto end.

39. 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;

an image-side lens unit having a positive refractive power; and

an aperture stop which is disposed between the second lens unit and the fourth lens unit,

wherein the first lens unit includes a negative lens and a plurality of positive lenses,

at the time of zooming from a wide angle end to a telephoto end, a distance between the first lens unit and the second lens unit widens, a distance between the second lens unit and the third lens unit narrows, and a distance between the third lens unit and the fourth lens unit changes, and

the following conditional expressions (4) and (5) are satisfied:

0.05<( D G1IMt −D G1IMw )/ f t <0.22  (4)

20< f t /f w <50  (5)

where D G1IMt denotes a distance on the optical axis from an object-side surface of a lens nearest to the object side in the first lens unit up to the image, at the telephoto end,

D G1IMw denotes a distance on the optical axis from the object-side surface of a lens nearest to the object side in the first lens unit up to the image, at the wide angle end,

f t denotes a focal length of the overall zoom lens system at the telephoto end, and

f w denotes a focal length of the overall zoom lens system at the wide angle end, wherein

the number of lens elements in the first lens unit is three,

the number of lens elements in the second lens unit is three,

the number of lens elements in the third lens unit is three,

the following conditional expression (6-1) is satisfied

−0.056≦ f G2 /f t <−0.03  (6-1)

where f G2 denotes a focal length of the second lens unit,

the lens component is a lens of which, only two surfaces namely, an object-side surface and an image-side surface make a contact with air, in an optical path.

40. The zoom lens according to claim 39 , wherein

the fourth lens unit consists of one lens component,

the lens component is a lens of which, only two surfaces namely, an object-side surface and an image-side surface make a contact with air, in an optical path.

41. The zoom lens according to claim 39 , wherein

the image-side lens unit consists of one lens component, and

the lens component is a lens of which, only two surfaces namely, an object-side surface and an image-side surface make a contact with air, in an optical path.

42. The zoom lens according to claim 39 , wherein

the fourth lens unit consists of one lens component,

the image-side lens unit consists of one lens component, and

the lens component is a lens of which, only two surfaces namely, an object-side surface and an image-side surface make a contact with air, in an optical path.

43. The zoom lens according to claim 42 , wherein

the following conditional expression (2) is satisfied

0.2< D ASIMt /f t <0.40  (2)

where D ASIMt denotes a distance on the optical axis from the aperture stop up to an image, at the telephoto end.

Assignments (3)
ASSIGNMENT OF ASSIGNOR'S INTEREST Recorded Dec 7, 2021
From: OLYMPUS CORPORATION
To: OM DIGITAL SOLUTIONS CORPORATION
Reel/Frame 058329/0766 →
ASSIGNMENT OF ASSIGNOR'S INTEREST Recorded Feb 11, 2016
From: MIMURA, TAKAYUKI; IMAMURA, MASAHIRO; AMANAI, TAKAHIRO
To: OLYMPUS CORPORATION; OLYMPUS IMAGING CORP.
Reel/Frame 037713/0476 →
CHANGE OF NAME Recorded Feb 11, 2016
From: OLYMPUS IMAGING CORP.
To: OLYMPUS CORPORATION
Reel/Frame 038079/0454 →