阅读说明：本技术 变焦透镜和图像拾取装置 (Zoom lens and image pickup apparatus ) 是由 宫泽伸幸 于 2019-06-05 设计创作，主要内容包括：本申请涉及变焦透镜和图像拾取装置。变焦透镜,从物侧起依次包括：正的第一单元；负的第二单元；正的中间组,由一个或两个单元组成并且包括位于最物侧的第三单元；负的单元；以及后组,由包括位于最物侧的正的单元的一个或两个单元组成。关于第二单元和第三单元从广角端到望远端的移动量、广角端处从第一单元中的最物侧表面顶点到第三单元中的最物侧表面顶点的距离、第一单元中的最物侧透镜的阿贝数、第二单元的焦距以及广角端处和望远端处的焦距,满足条件表达式。(The present application relates to a zoom lens and an image pickup apparatus. A zoom lens comprising, in order from an object side: a positive first cell; a negative second cell; a positive intermediate group consisting of one or two units and including a third unit located on the most object side; a negative cell; and a rear group consisting of one or two units including a positive unit located on the most object side. Conditional expressions are satisfied with respect to amounts of movement of the second unit and the third unit from a wide-angle end to a telephoto end, a distance from a most object side surface vertex in the first unit to a most object side surface vertex in the third unit at the wide-angle end, an abbe number of a most object side lens in the first unit, a focal length of the second unit, and focal lengths at the wide-angle end and the telephoto end.)

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;

an intermediate lens group composed of one or two lens units having positive refractive power, the one or two lens units including a third lens unit located on the most object side in the intermediate lens group;

A lens unit having a negative refractive power; and

A rear lens group composed of one or two lens units including a lens unit having a positive refractive power and located on the most object side in the rear lens group,

Wherein the interval between each pair of two adjacent lens units is changed for zooming,

Wherein each of the first lens unit and the second lens unit includes at least three lenses, an

Wherein the following conditional expressions are satisfied:

-10<m2/m3<-0.5；

2.0<L3w/fw<8.7；

27.0< v 1< 45.0; and

-0.4<f2/ft<-0.1，

Where m2 is a movement amount of the second lens unit from the wide angle end to the telephoto end, m3 is a movement amount of the third lens unit from the wide angle end to the telephoto end, each of m2 and m3 has a positive value in a case where a corresponding lens unit at the telephoto end is located on the image side with respect to the corresponding lens unit at the wide angle end, L3w is a distance from a vertex of a lens surface located closest to the object side in the first lens unit to a vertex of a lens surface located closest to the object side in the third lens unit at the wide angle end, ν 1 is an abbe number of a lens located closest to the object side in the first lens unit, f2 is a focal length of the second lens unit, fw is a focal length at the wide angle end, and ft is a focal length at the telephoto end.

2. The zoom lens according to claim 1, wherein a conditional expression is satisfied

3<ft/fw<10。

3. The zoom lens according to claim 1, wherein a conditional expression is satisfied

0.5<D1/fw<1.7，

Where D1 is the thickness on the optical axis of the first lens unit.

4. The zoom lens according to claim 1, wherein a conditional expression is satisfied

0.17<D1/f1<0.28，

Where D1 is a thickness on an optical axis of the first lens unit, and f1 is a focal length of the first lens unit.

5. The zoom lens according to claim 1, wherein a conditional expression is satisfied

-1.6<m3/fw<-0.55。

6. The zoom lens according to claim 1, wherein a conditional expression is satisfied

-1.5<f2/fw<-0.6。

7. The zoom lens according to claim 1, wherein a conditional expression is satisfied

65<ν2<98，

Where ν 2 is an abbe number of a second most object-side positioned lens in the first lens unit.

8. The zoom lens according to claim 1, wherein a conditional expression is satisfied

0.25<L23w/TDw<0.45，

Where L23w is a distance from a vertex of a lens surface located closest to the image side in the second lens unit to a vertex of a lens surface located closest to the object side in the third lens unit at the wide-angle end, and TDw is a total length of the zoom lens at the wide-angle end.

9. The zoom lens according to claim 1, wherein a conditional expression is satisfied

0.5<f2/fn2<1.0，

Where fn2 is a focal length of a lens unit located closest to the object side, of lens units having negative refractive power and arranged on the image side with respect to the third lens unit.

10. An image pickup apparatus characterized by comprising:

A variable focus lens as claimed in any one of claims 1 to 9; and

An image pickup element located on an image plane of the zoom lens.

11. The image pickup apparatus according to claim 10, wherein in the zoom lens, a conditional expression is satisfied

3<ft/fw<10。

12. The image pickup apparatus according to claim 10, wherein in the zoom lens, a conditional expression is satisfied

0.5<D1/fw<1.7，

Where D1 is the thickness on the optical axis of the first lens unit.

13. The image pickup apparatus according to claim 10, wherein in the zoom lens, a conditional expression is satisfied

0.17<D1/f1<0.28，

where D1 is a thickness on an optical axis of the first lens unit, and f1 is a focal length of the first lens unit.

14. The image pickup apparatus according to claim 10, wherein in the zoom lens, a conditional expression is satisfied

-1.6<m3/fw<-0.55。

15. the image pickup apparatus according to claim 10, wherein in the zoom lens, a conditional expression is satisfied

-1.5<f2/fw<-0.6。

16. The image pickup apparatus according to claim 10, wherein in the zoom lens, a conditional expression is satisfied

65<ν2<98，

where ν 2 is an abbe number of a second most object-side positioned lens in the first lens unit.

17. The image pickup apparatus according to claim 10, wherein in the zoom lens, a conditional expression is satisfied

0.25<L23w/TDw<0.45，

Where L23w is a distance from a vertex of a lens surface located closest to the image side in the second lens unit to a vertex of a lens surface located closest to the object side in the third lens unit at the wide-angle end, and TDw is a total length of the zoom lens at the wide-angle end.

18. The image pickup apparatus according to claim 10, wherein in the zoom lens, a conditional expression is satisfied

0.5<f2/fn2<1.0，

Where fn2 is a focal length of a lens unit located closest to the object side, of lens units having negative refractive power and arranged on the image side with respect to the third lens unit.

Technical Field

Background

In recent years, along with the benefits of high-definition monitors, zoom lenses to be mounted on digital still cameras, video cameras, television cameras, and the like have been faced with an increasing demand for improving image quality without affecting size reduction. In terms of improvement in image quality, if there is a large color difference, high resolution may still result in poor reproducibility of an object. In this respect, reduction of chromatic aberration is an important issue.

As a zoom lens capable of efficiently ensuring a zoom ratio in a small size, there has heretofore been known a zoom lens configured to correct an image plane movement associated with zooming by using a first lens unit having a positive refractive power, a second lens unit having a negative refractive power, and a third lens unit having a positive refractive power, which are arranged in order from an object side, and more lens units positioned closer to the image side than the third lens unit.

For example, international publication No. wo2013/136692 discloses a zoom lens having a zoom ratio of about 10 and including lens units having positive, negative, and positive refractive powers arranged in order from an object side, wherein a first lens unit and a fifth lens unit are configured not to move for zooming. Japanese patent application laid-open No.2012-242617 discloses a zoom lens having a zoom ratio of about 10 and including lens units having positive, negative, and positive refractive powers arranged in order from an object side, wherein the first lens unit includes a reflection member, and the first and fifth lens units are configured not to move for zooming.

International publication No. wo2013/136692 aims to achieve reduction in size by making the second lens unit, the third lens unit, and the fourth lens unit movable. Nevertheless, the zoom lens still has room for improvement in suppressing variation in chromatic aberration associated with zooming.

In japanese patent application laid-open No.2012-242617, the second lens unit and the lens unit disposed on the image side of the second lens unit have small diameters in order to manufacture a thin (slim) image pickup apparatus including an optical system configured to bend light with the reflective member in the first lens unit. Such a configuration still has a problem in reducing the overall length of the zoom lens.

Disclosure of Invention

The zoom lens of the present disclosure includes, in order from an object side to an image side: a first lens unit having a positive refractive power and configured not to move for zooming; a second lens unit having a negative refractive power; an intermediate lens group composed of one or two lens units having positive refractive power, including a third lens unit located on the most object side in the intermediate lens group; a lens unit having a negative refractive power; and a rear lens group composed of one or two lens units including a lens unit having a positive refractive power and located on the most object side in the rear lens group. Here, the interval between each pair of two adjacent lens units is changed to perform zooming. Each of the first lens unit and the second lens unit includes at least three lenses. Satisfying the conditional expression:

-10<m2/m3<-0.5；

2.0<L3w/fw<8.7；

27.0< v 1< 45.0; and

-0.4<f2/ft<-0.1,

Where m2 is a movement amount of the second lens unit from the wide angle end to the telephoto end, m3 is a movement amount of the third lens unit from the wide angle end to the telephoto end, each of m2 and m3 has a positive value in a case where a corresponding lens unit at the telephoto end is located on the image side with respect to the corresponding lens unit at the wide angle end, L3w is a distance from a vertex of a lens surface located closest to the object side in the first lens unit to a vertex of a lens surface located closest to the object side in the third lens unit at the wide angle end, ν 1 is an abbe number of a lens located closest to the object side in the first lens unit, f2 is a focal length of the second lens unit, fw is a focal length at the wide angle end, and ft is a focal length at the telephoto end.

Other features of the present disclosure will become apparent from the following description of exemplary embodiments with reference to the attached drawings.

Drawings

Fig. 1 is a sectional view of a lens in an optical system of numerical embodiment 1.

Fig. 2 illustrates an aberration diagram at the wide-angle end of numerical example 1.

Fig. 3 illustrates an aberration diagram at an intermediate focal length of numerical embodiment 1.

fig. 4 illustrates an aberration diagram at the telephoto end in numerical example 1.

Fig. 5 is a sectional view of a lens in an optical system of numerical embodiment 2.

Fig. 6 illustrates an aberration diagram at the wide-angle end of numerical example 2.

Fig. 7 illustrates an aberration diagram at an intermediate focal length of numerical example 2.

fig. 8 illustrates an aberration diagram at the telephoto end in numerical example 2.

Fig. 9 is a sectional view of a lens in an optical system of numerical embodiment 3.

Fig. 10 illustrates an aberration diagram at the wide-angle end of numerical example 3.

Fig. 11 illustrates an aberration diagram at an intermediate focal length of numerical embodiment 3.

Fig. 12 illustrates an aberration diagram at the telephoto end in numerical example 3.

Fig. 13 is a sectional view of a lens in an optical system of numerical embodiment 4.

fig. 14 illustrates an aberration diagram at the wide-angle end of numerical example 4.

Fig. 15 illustrates an aberration diagram at an intermediate focal length of numerical example 4.

Fig. 16 illustrates an aberration diagram at the telephoto end of numerical example 4.

Fig. 17 is a diagram for explaining an image pickup apparatus according to an embodiment of the present disclosure.

One aspect of the embodiments relates to a zoom lens and an image pickup apparatus.