JP2012212087A - Zoom lens, optical device, and zoom lens manufacturing method - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a zoom lens achieving high brightness and having a large variable power ratio and high optical performance.SOLUTION: The zoom lens includes, in order from an object side, a first lens group G1 having a positive refractive power, a second lens group G2 having a negative refractive power, a third lens group G3 having a positive refractive power, and a fourth lens group G4. During zooming from a wide angle end state W to a telephoto end state T, the distance between the first lens group G1 and the second lens group G2, the distance between the second lens group G2 and the third lens group G3 and the distance between the third lens group G3 and the fourth lens group G4 are changed. At least a part of the lens groups located closer to the image side than the third lens group G3 is moved as a vibration-proof lens group so as to include a component in a direction perpendicular to an optical axis. The vibration-proof lens group has a positive refractive power. The zoom lens satisfies predetermined conditional expressions.

Description

  The present invention relates to a zoom lens, an optical device, and a method for manufacturing a zoom lens.

  Conventionally, zoom lenses suitable for photographic cameras, electronic still cameras, video cameras, and the like have been proposed (see, for example, Patent Document 1).

JP 2002-296501 A

However, the conventional zoom lens has a problem that it is difficult to increase the zoom ratio while maintaining the brightness.
Accordingly, the present invention has been made in view of the above problems, and an object thereof is to provide a zoom lens, an optical device, and a zoom lens manufacturing method that are bright, have a large zoom ratio, and have high optical performance. To do.

In order to solve the above problems, the present invention
In order from the object side, a first lens group having a positive refractive power, a second lens group having a negative refractive power, a third lens group having a positive refractive power, and a fourth lens group,
Upon zooming from the wide-angle end state to the telephoto end state, the distance between the first lens group and the second lens group, the distance between the second lens group and the third lens group, and the third lens group and the first lens group The distance between the 4 lens groups changes,
The lens unit positioned on the image side of the third lens unit moves so as to include a component in a direction orthogonal to the optical axis as an anti-vibration lens unit,
The anti-vibration lens group has a positive refractive power;
Provided is a zoom lens that satisfies the following conditional expression.
0.20 <f1 / fRw <0.80
0.25 <f2 / f3 <0.60
However,
fRw: focal length f1 of the entire lens located on the image side of the third lens group at the wide-angle end state: focal length f2 of the first lens group: focal length f3 of the second lens group: third lens group Focal length

The present invention also provides
An optical apparatus comprising the zoom lens is provided.
The present invention also provides
A zoom lens having, in order from the object side, a first lens group having a positive refractive power, a second lens group having a negative refractive power, a third lens group having a positive refractive power, and a fourth lens group A manufacturing method of
Upon zooming from the wide-angle end state to the telephoto end state, the distance between the first lens group and the second lens group, the distance between the second lens group and the third lens group, and the third lens group and the first lens group The distance between the four lens groups changes,
And at least a part of the lens group positioned on the image side of the third lens group moves so as to include a component in a direction orthogonal to the optical axis as a vibration-proof lens group,
The anti-vibration lens group has a positive refractive power,
A zoom lens manufacturing method is provided that satisfies the following conditional expression.
0.20 <f1 / fRw <0.80
0.25 <f2 / f3 <0.60
However,
fRw: focal length f1 of the entire lens located on the image side of the third lens group at the wide-angle end state: focal length f2 of the first lens group: focal length f3 of the second lens group: third lens group Focal length

  According to the present invention, it is possible to provide a zoom lens, an optical device, and a zoom lens manufacturing method that are bright, have a large zoom ratio, and have high optical performance.

It is sectional drawing which shows the structure of the zoom lens which concerns on 1st Example of this application. (A), (b), and (c) are various aberration diagrams during focusing on an object at infinity in the wide-angle end state, intermediate focal length state, and telephoto end state of the zoom lens according to Example 1 of the present application, respectively. It is. (A) and (b) are respectively meridional when vibration is prevented against 0.42 ° rotation blur when focusing on an object at infinity in the wide-angle end state of the zoom lens according to Example 1 of the present application. FIG. 6 is a lateral aberration diagram and a meridional lateral aberration diagram when performing vibration isolation for a rotational shake of 0.18 ° during focusing on an object at infinity in the telephoto end state. It is sectional drawing which shows the structure of the zoom lens which concerns on 2nd Example of this application. (A), (b), and (c) are various aberration diagrams when focusing on an object at infinity in the wide-angle end state, intermediate focal length state, and telephoto end state of the zoom lens according to Example 2 of the present application, respectively. It is. (A) and (b) are respectively meridional when the vibration is prevented against 0.42 ° rotation blur at the time of focusing on an object at infinity in the wide-angle end state of the zoom lens according to Example 2 of the present application. FIG. 6 is a lateral aberration diagram and a meridional lateral aberration diagram when performing vibration isolation for a rotational shake of 0.18 ° during focusing on an object at infinity in the telephoto end state. It is sectional drawing which shows the structure of the zoom lens which concerns on 3rd Example of this application. (A), (b), and (c) are graphs showing various aberrations during focusing on an object at infinity in the wide-angle end state, intermediate focal length state, and telephoto end state of the zoom lens according to Example 3 of the present application, respectively. It is. (A) and (b) are respectively meridional when the vibration is prevented against a rotational blur of 0.42 ° at the time of focusing on an object at infinity in the wide-angle end state of the zoom lens according to Example 3 of the present application. FIG. 6 is a lateral aberration diagram and a meridional lateral aberration diagram when performing vibration isolation for a rotational shake of 0.18 ° during focusing on an object at infinity in the telephoto end state. It is sectional drawing which shows the structure of the zoom lens which concerns on 4th Example of this application. (A), (b), and (c) are various aberration diagrams during focusing on an object at infinity in the wide-angle end state, intermediate focal length state, and telephoto end state of the zoom lens according to Example 4 of the present application, respectively. It is. (A) and (b) are respectively meridional when the vibration is prevented against 0.42 ° rotation blur at the time of focusing on an object at infinity in the wide-angle end state of the zoom lens according to Example 4 of the present application. FIG. 6 is a lateral aberration diagram and a meridional lateral aberration diagram when performing vibration isolation for a rotational shake of 0.18 ° during focusing on an object at infinity in the telephoto end state. It is sectional drawing which shows the structure of the zoom lens which concerns on 5th Example of this application. (A), (b), and (c) are graphs showing various aberrations during focusing on an object at infinity in the wide-angle end state, intermediate focal length state, and telephoto end state of the zoom lens according to Example 5 of the present application. It is. (A) and (b) are respectively meridional when a vibration of 0.42 ° is prevented from being shaken at the time of focusing on an object at infinity in the wide-angle end state of the zoom lens according to Example 5 of the present application. FIG. 6 is a lateral aberration diagram and a meridional lateral aberration diagram when performing vibration isolation for a rotational shake of 0.18 ° during focusing on an object at infinity in the telephoto end state. It is a figure which shows the structure of the camera provided with the zoom lens of this application. It is a figure which shows the outline of the manufacturing method of the zoom lens of this application.

Hereinafter, the zoom lens, the optical device, and the manufacturing method of the zoom lens of the present application will be described.
The zoom lens according to the present application includes, in order from the object side, a first lens group having a positive refractive power, a second lens group having a negative refractive power, a third lens group having a positive refractive power, and a fourth lens. And a distance between the first lens group and the second lens group, a distance between the second lens group and the third lens group, and the first lens group during zooming from the wide-angle end state to the telephoto end state. The distance between the third lens group and the fourth lens group changes, and at least a part of the lens group located on the image side of the third lens group includes a component in a direction perpendicular to the optical axis as an anti-vibration lens group. The anti-vibration lens group has a positive refractive power and satisfies the following conditional expressions (1) and (2).
(1) 0.20 <f1 / fRw <0.80
(2) 0.25 <f2 / f3 <0.60
However,
fRw: focal length f1 of the entire lens located on the image side of the third lens group at the wide-angle end state: focal length f2 of the first lens group: focal length f3 of the second lens group: third lens group Focal length

With such a configuration, it is possible to realize a zoom lens that is bright and has a large zoom ratio and high optical performance.
Conditional expression (1) defines the focal length of the first lens group with respect to the focal length in the wide-angle end state of the entire lens positioned on the image side relative to the third lens group. The zoom lens of the present application can satisfactorily correct the field curvature in the wide-angle end state and the spherical aberration in the telephoto end state by satisfying conditional expression (1).
If the corresponding value of the conditional expression (1) of the zoom lens of the present application exceeds the upper limit value, the zooming effect of the first lens group is reduced. Therefore, the refractive power of the second lens group is increased to ensure the zoom ratio. There must be. As a result, field curvature occurs in the wide-angle end state, and spherical aberration occurs in the telephoto end state. In order to secure the effect of the present application, it is more preferable to set the upper limit of conditional expression (1) to 0.75.
On the other hand, if the corresponding value of conditional expression (1) of the zoom lens of the present application is lower than the lower limit value, the refractive power of the first lens unit becomes large, and it becomes difficult to correct spherical aberration in the telephoto end state. It is not preferable. In order to secure the effect of the present application, it is more preferable to set the lower limit of conditional expression (1) to 0.25.

Conditional expression (2) defines the focal length of the second lens group with respect to the focal length of the third lens group. The zoom lens of the present application can satisfactorily correct the field curvature in the wide-angle end state and the spherical aberration in the telephoto end state by satisfying conditional expression (2).
If the corresponding value of the conditional expression (2) of the zoom lens of the present application exceeds the upper limit value, the refractive power of the third lens unit increases, and it becomes difficult to correct spherical aberration in the telephoto end state, which is not preferable. . In order to secure the effect of the present application, it is more preferable to set the upper limit of conditional expression (2) to 0.55.
On the other hand, when the corresponding value of the conditional expression (2) of the zoom lens of the present application is below the lower limit value, the refractive power of the second lens group increases, and the field curvature in the wide-angle end state and the spherical aberration in the telephoto end state are corrected. This is not preferable because it becomes difficult. In order to secure the effect of the present application, it is more preferable to set the lower limit of conditional expression (2) to 0.30.

In the zoom lens of the present application, it is desirable that the fourth lens group has a positive refractive power. With this configuration, spherical aberration can be corrected well in the telephoto end state.
In the zoom lens according to the present application, it is desirable that the first lens group moves toward the object side upon zooming from the wide-angle end state to the telephoto end state. With this configuration, it is possible to reduce the refractive power of each lens group involved in zooming and to ensure good optical performance over the entire zoom range.
In the zoom lens of the present application, it is desirable that the fourth lens group moves to the object side upon zooming from the wide-angle end state to the telephoto end state. With this configuration, it is possible to reduce the refractive power of each lens group involved in zooming and to ensure good optical performance over the entire zoom range.
In the zoom lens of the present application, it is desirable that the third lens group is moved to perform focusing from an object at infinity to a near object. In the zoom lens of the present application, the third lens group is small and light, and by performing focusing with such a third lens group, rapid focusing can be realized.

Moreover, it is desirable that the zoom lens of the present application satisfies the following conditional expression (3).
(3) 0.20 <f3 / fRw <0.50
However,
fRw: focal length in the wide-angle end state of the entire lens located on the image side of the third lens group f3: focal length of the third lens group

Conditional expression (3) defines the focal length of the third lens group with respect to the focal length in the wide-angle end state of the entire lens located on the image side of the third lens group. The zoom lens of the present application can satisfactorily correct spherical aberration in the telephoto end state and field curvature in the wide-angle end state by satisfying conditional expression (3).
When the corresponding value of the conditional expression (3) of the zoom lens of the present application exceeds the upper limit value, the zooming effect of the third lens group becomes small, so that the zoom ratio of the first lens group or the second lens group is ensured to ensure the zooming ratio. The refractive power must be increased. As a result, it becomes difficult to correct spherical aberration in the telephoto end state and field curvature in the wide-angle end state, which is not preferable. In order to secure the effect of the present application, it is more preferable to set the upper limit of conditional expression (3) to 0.45.
On the other hand, if the corresponding value of conditional expression (3) of the zoom lens of the present application is lower than the lower limit value, the refractive power of the third lens group becomes large, and it becomes difficult to correct spherical aberration in the telephoto end state. It is not preferable. In addition, when the zoom lens of the present application is configured to focus with the third lens group, it is not preferable because aberration fluctuation at the time of focusing becomes large. In order to secure the effect of the present application, it is more preferable to set the lower limit of conditional expression (3) to 0.25.

  In the zoom lens according to the present application, it is preferable that the vibration-proof lens group includes a cemented lens of one positive lens and one negative lens. With this configuration, it is possible to satisfactorily correct decentration coma aberration when the anti-vibration lens group moves so as to include a component in a direction orthogonal to the optical axis.

Moreover, it is desirable that the zoom lens of the present application satisfies the following conditional expression (4).
(4) 1.00 <f1 / f3 <2.20
However,
f1: Focal length of the first lens group f3: Focal length of the third lens group

Conditional expression (4) defines the focal length of the first lens group with respect to the focal length of the third lens group. The zoom lens of the present application can satisfactorily correct spherical aberration in the telephoto end state and field curvature in the wide-angle end state by satisfying conditional expression (4).
If the corresponding value of the conditional expression (4) of the zoom lens of the present application exceeds the upper limit value, the zooming effect of the first lens group is reduced. Therefore, the refractive power of the second lens group is increased to ensure the zoom ratio. There must be. As a result, field curvature occurs in the wide-angle end state, and spherical aberration occurs in the telephoto end state. In order to secure the effect of the present application, it is more preferable to set the upper limit of conditional expression (4) to 2.00.
On the other hand, when the corresponding value of the conditional expression (4) of the zoom lens of the present application is less than the lower limit value, the zooming effect of the third lens group becomes small. Therefore, the first lens group or the second lens in order to ensure the zooming ratio. The power of the group must be increased. As a result, it becomes difficult to correct spherical aberration in the telephoto end state and field curvature in the wide-angle end state, which is not preferable. In order to secure the effect of the present application, it is more preferable to set the lower limit of conditional expression (4) to 1.10.

In the zoom lens of the present application, it is desirable that the lens surfaces of all the lenses in the zoom lens are spherical or flat. With this configuration, lens processing and assembly adjustment are facilitated, and deterioration of optical performance due to errors in lens processing and assembly adjustment can be prevented. In addition, even when the image plane is deviated, it is possible to reduce the degradation of the drawing performance.
The optical device of the present application includes the zoom lens having the above-described configuration. Thereby, it is possible to realize an optical device that is bright, has a large zoom ratio, and has high optical performance.

The zoom lens manufacturing method according to the present application includes, in order from the object side, a first lens group having a positive refractive power, a second lens group having a negative refractive power, and a third lens group having a positive refractive power. And a fourth lens group, and a zoom lens from the wide-angle end state to the telephoto end state, the distance between the first lens group and the second lens group, and the second lens group And the distance between the third lens group and the distance between the third lens group and the fourth lens group are changed, and at least a part of the lens group positioned on the image side of the third lens group is prevented. The vibration lens group is moved so as to include a component in a direction orthogonal to the optical axis so that the vibration-proof lens group has a positive refractive power, and the following conditional expressions (1) and (2) are satisfied. It is characterized by doing so.
(1) 0.20 <f1 / fRw <0.80
(2) 0.25 <f2 / f3 <0.60
However,
fRw: focal length f1 of the entire lens located on the image side of the third lens group at the wide-angle end state: focal length f2 of the first lens group: focal length f3 of the second lens group: third lens group The zoom lens according to the present invention can produce a zoom lens that is bright, has a large zoom ratio, and has high optical performance.

Hereinafter, zoom lenses according to numerical examples of the present application will be described with reference to the accompanying drawings.
(First embodiment)
FIG. 1 is a cross-sectional view showing the configuration and zoom trajectory of a zoom lens according to Example 1 of the present application.
The zoom lens according to the present embodiment includes, in order from the object side, a first lens group G1 having a positive refractive power, a second lens group G2 having a negative refractive power, and a third lens group having a positive refractive power. G3 and a fourth lens group G4 having a positive refractive power.
The first lens group G1 includes, in order from the object side, a cemented lens of a negative meniscus lens L11 having a convex surface facing the object side and a positive meniscus lens L12 having a convex surface facing the object side, and a positive meniscus having a convex surface facing the object side. It consists of a lens L13 and a positive meniscus lens L14 having a convex surface facing the object side.
The second lens group G2 includes, in order from the object side, a negative meniscus lens L21 having a convex surface directed toward the object side, a cemented lens of a biconcave negative lens L22 and a biconvex positive lens L23, and a concave surface on the object side. And a negative meniscus lens L24 facing the lens.

The third lens group G3 includes, in order from the object side, a biconvex positive lens L31, and a cemented lens of a negative meniscus lens L32 having a convex surface facing the object side and a biconvex positive lens L33.
The fourth lens group G4 includes, in order from the object side, a first partial group G41, a second partial group G42, a fixed stop ST, and a third partial group G43.
The first partial group G41 has, in order from the object side, a negative meniscus lens L41 having a concave surface directed toward the object side, a positive meniscus lens L42 having a convex surface directed toward the object side, an aperture stop S, and a convex surface directed toward the object side. It comprises a positive meniscus lens L43, a negative meniscus lens L44 having a convex surface facing the object side, and a positive meniscus lens L45 having a concave surface facing the object side.
The second partial group G42 includes, in order from the object side, a cemented lens of a biconvex positive lens L46 and a negative meniscus lens L47 with a concave surface facing the object side.
The third partial group G43 includes, in order from the object side, a cemented lens of a biconvex positive lens L48 and a negative meniscus lens L49 having a concave surface facing the object side, a biconcave negative lens L410, and a biconvex shape. And a positive lens L411.

In the zoom lens according to the present embodiment, the air gap between the first lens group G1 and the second lens group G2 increases during zooming from the wide-angle end state to the telephoto end state, and the second lens group G2 and the third lens. The first lens group G1, the third lens group G3, and the fourth lens group G4 are arranged such that the air gap between the group G3 decreases and the air gap between the third lens group G3 and the fourth lens group G4 changes. Moving to the object side along the optical axis, the second lens group G2 moves along the optical axis. At this time, the aperture stop S and the fixed stop ST move together with the fourth lens group G4.
In the zoom lens according to the present embodiment, focusing from an object at infinity to a near object is performed by moving the third lens group G3 along the optical axis toward the object side.
In the zoom lens according to the present embodiment, the second partial group G42 having positive refractive power is moved as a vibration-proof lens group so as to include a component in a direction orthogonal to the optical axis, thereby causing an image caused by camera shake or the like. Shake correction, that is, image stabilization is performed.

Table 1 below lists values of specifications of the zoom lens according to the present example.
In Table 1, f indicates the focal length, and BF indicates the back focus.
In [Surface data], the surface number is the order of the lens surfaces counted from the object side, r is the radius of curvature of the lens surfaces, d is the distance between the lens surfaces, nd is the refractive index with respect to the d-line (wavelength λ = 587.6 nm), νd represents the Abbe number for the d-line (wavelength λ = 587.6 nm). The object plane is the object plane, the variable is the variable surface interval, the aperture S is the aperture stop S, the aperture ST is the fixed aperture ST, and the image plane is the image plane I. The radius of curvature r = ∞ indicates a plane.

In [various data], FNO is the F number, 2ω is the angle of view (unit is “°”), Y is the image height, TL is the total length of the zoom lens, and di (i: integer) is the variable surface distance of the i-th surface. Each is shown. Note that W indicates when the object at infinity is in the wide-angle end state, M indicates when the object at infinity is in the intermediate focal length state, and T indicates when the object at infinity is in the telephoto end state.
Here, “mm” is generally used as a unit of the focal length f, the radius of curvature r, and other lengths listed in Table 1. However, the optical system is not limited to this because an equivalent optical performance can be obtained even when proportionally enlarged or proportionally reduced.
In addition, the code | symbol of Table 1 described above shall be similarly used also in the table | surface of each Example mentioned later.

  Here, in a lens in which the focal length of the entire lens system is f and the image stabilization coefficient (ratio of the image movement amount on the image plane I to the movement amount of the image stabilization lens group during image stabilization) is K, the angle θ In order to correct the rotational blur of the lens, the anti-vibration lens group may be moved in a direction orthogonal to the optical axis by (f · tan θ) / K. Accordingly, the zoom lens according to the present example has an image stabilization coefficient of 1.05 and a focal length of 56.5 (mm) in the wide-angle end state, and thus image stabilization for correcting a rotation blur of 0.42 °. The amount of movement of the lens group is 0.39 (mm). Further, in the telephoto end state, since the image stabilization coefficient is 1.43 and the focal length is 292.0 (mm), the amount of movement of the image stabilization lens group for correcting the rotation blur of 0.18 ° is 0. 66 (mm).

(Table 1) First Example
[Surface data]
Surface number r d nd νd
Object ∞
1) 159.637 2.000 1.954000 33.40
2) 86.309 9.350 1.497820 82.51
3) 1968.330 0.100 1.000000
4) 93.118 8.323 1.497820 82.51
5) 1123.754 0.100 1.000000
6) 112.716 6.244 1.497820 82.51
7) 671.637 Variable 1.000000
8) 143.987 1.800 1.882997 40.76
9) 35.088 13.150 1.000000
10) -62.101 1.400 1.497820 82.51
11) 45.517 5.302 1.808090 22.79
12) -826.672 3.285 1.000000
13) -46.887 1.400 1.754998 52.32
14) -139.482 Variable 1.000000
15) 79.829 4.770 1.882997 40.76
16) -1868.367 0.100 1.000000
17) 78.140 1.400 1.843954 31.16
18) 34.986 8.448 1.497820 82.51
19) -883.296 Variable 1.000000
20) -57.083 1.400 1.705047 47.46
21) -176.045 0.100 1.000000
22) 50.5093 4.794 1.668801 48.28
23) 192.204 2.019 1.000000
24) (Aperture S) ∞ 1.000 1.000000
25) 119.535 3.253 1.816947 45.56
26) 10389.026 12.560 1.000000
27) 445.977 1.400 1.869541 33.05
28) 45.626 3.527 1.000000
29) -171.158 2.752 1.529669 75.71
30) -69.464 2.000 1.000000
31) 48.388 6.921 1.624183 62.79
32) -48.626 1.000 1.871708 33.53
33) -185.908 8.086 1.000000
34) (Aperture ST) ∞ 10.060 1.000000
35) 228.218 5.386 1.846660 23.78
36) -31.013 1.000 1.882880 40.67
37) -300.558 4.594 1.000000
38) -35.150 1.400 1.872501 33.96
39) 187.079 0.100 1.000000
40) 63.502 4.769 1.608609 64.70
41) -106.328 BF 1.000000
Image plane ∞

[Various data]
Scaling ratio 5.17
W M T
f 56.50 105.00 292.00
FNO 2.88 3.40 4.12
2ω 43.34 23.13 8.35
Y 21.60 21.60 21.60
TL 248.90 267.80 288.60
BF 38.47 52.49 62.51

W M T
d7 2.000 22.988 47.484
d14 51.268 34.945 2.400
d19 11.874 12.089 30.913

[Zoom lens group data]
Group start surface f
1 1 112.565
2 8 -29.778
3 15 76.546
4 20 234.232

[Conditional expression values]
(1) f1 / fRw = 0.48
(2) f2 / f3 = 0.39
(3) f3 / fRw = 0.33
(4) f1 / f3 = 1.47

2 (a), 2 (b), and 2 (c) respectively show the infinite object combination in the wide-angle end state, the intermediate focal length state, and the telephoto end state of the zoom lens according to Example 1 of the present application. FIG. 5 is a diagram showing various aberrations during focusing.
3 (a) and 3 (b) respectively perform vibration isolation against rotation blur of 0.42 ° when focusing on an object at infinity in the wide-angle end state of the zoom lens according to Example 1 of the present application. FIG. 6 is a meridional lateral aberration diagram when the object is in focus, and a meridional lateral aberration diagram when the image stabilization is performed with respect to a rotational shake of 0.18 ° when focusing on an object at infinity in the telephoto end state.

In each aberration diagram, FNO represents an F number, and Y represents an image height. d indicates the aberration at the d-line (λ = 587.6 nm) and g indicates the aberration at the g-line (λ = 435.8 nm). In the astigmatism diagram, the solid line indicates the sagittal image plane, and the broken line indicates the meridional image plane. Note that the same reference numerals as in this embodiment are used in the aberration diagrams of each embodiment described later.
From each aberration diagram, the zoom lens according to the present embodiment has excellent imaging performance by correcting various aberrations well from the wide-angle end state to the telephoto end state, and also has excellent imaging performance during image stabilization. It can be seen that

(Second embodiment)
FIG. 4 is a cross-sectional view showing the configuration and zoom trajectory of the zoom lens according to Example 2 of the present application.
The zoom lens according to the present embodiment includes, in order from the object side, a first lens group G1 having a positive refractive power, a second lens group G2 having a negative refractive power, and a third lens group having a positive refractive power. G3 and a fourth lens group G4 having a positive refractive power.
The first lens group G1 includes, in order from the object side, a cemented lens of a negative meniscus lens L11 having a convex surface facing the object side and a positive meniscus lens L12 having a convex surface facing the object side, and a positive meniscus having a convex surface facing the object side. It consists of a lens L13 and a positive meniscus lens L14 having a convex surface facing the object side.
The second lens group G2 includes, in order from the object side, a negative meniscus lens L21 having a convex surface directed toward the object side, a cemented lens of a biconcave negative lens L22 and a biconvex positive lens L23, and a concave surface on the object side. And a negative meniscus lens L24 facing the lens.

The third lens group G3 includes, in order from the object side, a biconvex positive lens L31, and a cemented lens of a negative meniscus lens L32 having a convex surface facing the object side and a biconvex positive lens L33.
The fourth lens group G4 includes, in order from the object side, a first partial group G41, a second partial group G42, a fixed stop ST, and a third partial group G43.
The first partial group G41 includes, in order from the object side, a negative meniscus lens L41 having a concave surface directed toward the object side, an aperture stop S, a biconvex positive lens L42, a biconvex positive lens L43, and a biconcave shape. The negative lens L44, a biconcave negative lens L45, and a positive meniscus lens L46 having a concave surface facing the object side.
The second partial group G42 includes, in order from the object side, a cemented lens of a biconvex positive lens L47 and a biconcave negative lens L48.
The third partial group G43 includes, in order from the object side, a negative meniscus lens L49 having a concave surface directed toward the object side, and a biconvex positive lens L410.

In the zoom lens according to the present embodiment, the air gap between the first lens group G1 and the second lens group G2 increases during zooming from the wide-angle end state to the telephoto end state, and the second lens group G2 and the third lens. The first lens group G1 and the third lens group G3 are arranged on the object side along the optical axis so that the air gap between the group G3 decreases and the air gap between the third lens group G3 and the fourth lens group G4 changes. The second lens group G2 and the fourth lens group G4 move along the optical axis. At this time, the aperture stop S and the fixed stop ST move together with the fourth lens group G4.
In the zoom lens according to the present embodiment, focusing from an object at infinity to a near object is performed by moving the third lens group G3 along the optical axis toward the object side.
In the zoom lens according to the present embodiment, image stabilization is performed by moving the second partial group G42 having positive refractive power as an image stabilization lens group so as to include a component in a direction orthogonal to the optical axis.

Table 2 below lists values of specifications of the zoom lens according to the present example.
Here, the zoom lens according to the present example has an anti-vibration coefficient of 0.60 and a focal length of 56.5 (mm) in the wide-angle end state, and thus the anti-shake for correcting the rotational blur of 0.42 °. The moving amount of the vibration lens group is 0.69 (mm). Further, in the telephoto end state, since the image stabilization coefficient is 0.86 and the focal length is 292.0 (mm), the movement amount of the image stabilization lens group for correcting the rotation blur of 0.18 ° is 1. 09 (mm).

(Table 2) Second Example
[Surface data]
Surface number r d nd νd
Object ∞
1) 154.112 2.000 1.954000 33.40
2) 86.859 8.657 1.497820 82.51
3) 671.562 0.100 1.000000
4) 104.454 6.573 1.497820 82.51
5) 444.100 0.100 1.000000
6) 110.456 7.051 1.497820 82.51
7) 2926.483 Variable 1.000000
8) 117.422 1.800 1.871476 41.48
9) 33.802 12.912 1.000000
10) -52.781 1.400 1.497820 82.51
11) 47.042 5.109 1.808090 22.79
12) -435.901 3.112 1.000000
13) -45.306 1.400 1.754998 52.32
14) -143.089 Variable 1.000000
15) 134.125 3.780 1.735633 53.44
16) -524.846 0.100 1.000000
17) 61.789 1.400 1.903660 31.27
18) 38.674 9.494 1.497820 82.51
19) -131.479 Variable 1.000000
20) -58.040 1.400 1.747031 33.38
21) -152.165 1.000 1.000000
22) (Aperture S) ∞ 0.100 1.000000
23) 52.622 6.704 1.724597 42.98
24) -230.427 0.100 1.000000
25) 72.391 4.724 1.497820 82.51
26) -418.143 1.400 1.903660 31.27
27) 153.247 14.726 1.000000
28) -561.944 1.400 1.877930 39.80
29) 43.792 2.772 1.000000
30) -477.264 2.772 1.846660 23.78
31) -80.324 2.000 1.000000
32) 45.398 5.095 1.500693 81.81
33) -128.919 1.000 1.844551 37.17
34) 14667.913 4.373 1.000000
35) (Aperture ST) ∞ 15.954 1.000000
36) -26.663 1.400 1.701362 55.71
37) -69.844 0.100 1.000000
38) 79.777 4.454 1.556286 53.91
39) -117.603 BF 1.000000
Image plane ∞

[Various data]
Scaling ratio 5.17
W M T
f 56.50 105.00 292.00
FNO 2.88 3.40 4.12
2ω 43.47 23.28 8.41
Y 21.60 21.60 21.60
TL 230.71 256.42 287.85
BF 38.47 53.96 67.93

W M T
d7 4.662 27.912 55.792
d14 43.382 28.931 2.400
d19 7.743 9.161 25.265

[Zoom lens group data]
Group start surface f
1 1 124.062
2 8 -28.969
3 15 68.845
4 20 249.192

[Conditional expression values]
(1) f1 / fRw = 0.50
(2) f2 / f3 = 0.42
(3) f3 / fRw = 0.28
(4) f1 / f3 = 1.80

FIGS. 5 (a), 5 (b), and 5 (c) respectively show infinite objects in the wide-angle end state, the intermediate focal length state, and the telephoto end state of the zoom lens according to the second embodiment of the present application. FIG. 5 is a diagram showing various aberrations during focusing.
6 (a) and 6 (b) respectively perform vibration isolation against rotation blur of 0.42 ° at the time of focusing on an object at infinity in the wide-angle end state of the zoom lens according to Example 2 of the present application. FIG. 6 is a meridional lateral aberration diagram when the object is in focus, and a meridional lateral aberration diagram when the image stabilization is performed with respect to a rotational shake of 0.18 ° when focusing on an object at infinity in the telephoto end state.
From each aberration diagram, the zoom lens according to the present embodiment has excellent imaging performance by correcting various aberrations well from the wide-angle end state to the telephoto end state, and also has excellent imaging performance during image stabilization. It can be seen that

(Third embodiment)
FIG. 7 is a cross-sectional view showing the configuration and zoom trajectory of the zoom lens according to Example 3 of the present application.
The zoom lens according to the present embodiment includes, in order from the object side, a first lens group G1 having a positive refractive power, a second lens group G2 having a negative refractive power, and a third lens group having a positive refractive power. G3 and a fourth lens group G4 having a positive refractive power.
The first lens group G1 includes, in order from the object side, a cemented lens of a negative meniscus lens L11 having a convex surface facing the object side and a positive meniscus lens L12 having a convex surface facing the object side, and a positive meniscus having a convex surface facing the object side. A lens L13 and a biconvex positive lens L14 are included.
The second lens group G2 includes, in order from the object side, a negative meniscus lens L21 having a convex surface directed toward the object side, a cemented lens of a biconcave negative lens L22 and a biconvex positive lens L23, and a concave surface on the object side. And a negative meniscus lens L24 facing the lens.

The third lens group G3 includes, in order from the object side, a biconvex positive lens L31, and a cemented lens of a negative meniscus lens L32 having a convex surface facing the object side and a biconvex positive lens L33.
The fourth lens group G4 includes, in order from the object side, a first partial group G41, a second partial group G42, a fixed stop ST, and a third partial group G43.
The first partial group G41 includes, in order from the object side, a negative meniscus lens L41 having a concave surface directed toward the object side, an aperture stop S, a biconvex positive lens L42, a biconvex positive lens L43, and a biconcave shape. The negative lens L44, a biconcave negative lens L45, and a positive meniscus lens L46 having a concave surface facing the object side.
The second partial group G42 includes, in order from the object side, a cemented lens of a biconvex positive lens L47 and a biconcave negative lens L48.
The third partial group G43 includes, in order from the object side, a negative meniscus lens L49 having a concave surface directed toward the object side, and a biconvex positive lens L410.

In the zoom lens according to the present embodiment, the air gap between the first lens group G1 and the second lens group G2 increases during zooming from the wide-angle end state to the telephoto end state, and the second lens group G2 and the third lens. The first lens group G1, the third lens group G3, and the fourth lens group G4 are arranged so that the air gap between the group G3 decreases and the air gap between the third lens group G3 and the fourth lens group G4 increases. Moving to the object side along the optical axis, the position of the second lens group G2 is fixed. At this time, the aperture stop S and the fixed stop ST move together with the fourth lens group G4.
In the zoom lens according to the present embodiment, focusing from an object at infinity to a near object is performed by moving the third lens group G3 along the optical axis toward the object side.
In the zoom lens according to the present embodiment, image stabilization is performed by moving the second partial group G42 having positive refractive power as an image stabilization lens group so as to include a component in a direction orthogonal to the optical axis.

Table 3 below provides values of specifications of the zoom lens according to the present example.
Here, the zoom lens according to the present example has an anti-vibration coefficient of 0.60 and a focal length of 56.5 (mm) in the wide-angle end state, and thus the anti-shake for correcting the rotational blur of 0.42 °. The moving amount of the vibration lens group is 0.69 (mm). In the telephoto end state, since the image stabilization coefficient is 0.89 and the focal length is 292.0 (mm), the amount of movement of the image stabilization lens group for correcting the rotation blur of 0.18 ° is 1. 06 (mm).

(Table 3) Third Example
[Surface data]
Surface number r d nd νd
Object ∞
1) 150.563 2.000 1.954000 33.40
2) 87.296 8.204 1.497820 82.51
3) 497.684 0.100 1.000000
4) 137.118 5.179 1.497820 82.51
5) 513.574 0.100 1.000000
6) 101.027 8.036 1.497820 82.51
7) -2262.976 Variable 1.000000
8) 175.366 1.800 1.882997 40.76
9) 36.160 10.890 1.000000
10) -57.639 1.400 1.497820 82.51
11) 47.394 5.392 1.808090 22.79
12) -325.975 3.127 1.000000
13) -45.820 1.400 1.832545 44.26
14) -106.105 Variable 1.000000
15) 115.817 3.919 1.729114 53.84
16) -769.951 0.100 1.000000
17) 73.122 1.400 1.903660 31.27
18) 42.601 8.457 1.497820 82.51
19) -160.964 Variable 1.000000
20) -61.887 1.400 1.814629 33.03
21) -120.054 1.000 1.000000
22) (Aperture S) ∞ 0.100 1.000000
23) 48.434 6.898 1.720661 44.23
24) -452.148 0.100 1.000000
25) 63.021 5.397 1.497820 82.51
26) -333.861 1.400 1.903660 31.27
27) 138.714 14.521 1.000000
28) -412.542 1.400 1.882997 40.76
29) 43.577 2.931 1.000000
30) -370.582 2.850 1.846660 23.78
31) -74.356 2.000 1.000000
32) 44.549 4.980 1.497820 82.51
33) -155.808 1.000 1.854782 35.88
34) 1751.595 3.548 1.000000
35) (Aperture ST) ∞ 15.129 1.000000
36) -26.241 1.400 1.757329 52.01
37) -61.198 0.100 1.000000
38) 90.311 3.983 1.583720 43.84
39) -153.050 BF 1.000000
Image plane ∞

[Various data]
Scaling ratio 5.17
W M T
f 56.50 105.00 292.00
FNO 2.88 3.40 4.12
2ω 43.64 23.24 8.36
Y 21.60 21.60 21.60
TL 231.32 255.89 287.43
BF 38.47 55.65 69.03

W M T
d7 2.000 26.572 58.109
d14 45.826 30.394 2.400
d19 13.385 11.635 26.251

[Zoom lens group data]
Group start surface f
1 1 128.179
2 8 -31.138
3 15 77.048
4 20 213.555

[Conditional expression values]
(1) f1 / fRw = 0.60
(2) f2 / f3 = 0.40
(3) f3 / fRw = 0.36
(4) f1 / f3 = 1.66

8 (a), 8 (b), and 8 (c) respectively show the infinite object combination in the wide-angle end state, the intermediate focal length state, and the telephoto end state of the zoom lens according to Example 3 of the present application. FIG. 5 is a diagram showing various aberrations during focusing.
FIG. 9A and FIG. 9B each perform vibration isolation against rotation blur of 0.42 ° when focusing on an object at infinity in the wide-angle end state of the zoom lens according to the third example of the present application. FIG. 6 is a meridional lateral aberration diagram when the object is in focus, and a meridional lateral aberration diagram when the image stabilization is performed with respect to a rotational shake of 0.18 ° when focusing on an object at infinity in the telephoto end state.
From each aberration diagram, the zoom lens according to the present embodiment has excellent imaging performance by correcting various aberrations well from the wide-angle end state to the telephoto end state, and also has excellent imaging performance during image stabilization. It can be seen that

(Fourth embodiment)
FIG. 10 is a cross-sectional view showing the configuration and zoom trajectory of the zoom lens according to Example 4 of the present application.
The zoom lens according to the present embodiment includes, in order from the object side, a first lens group G1 having a positive refractive power, a second lens group G2 having a negative refractive power, and a third lens group having a positive refractive power. G3 includes a fourth lens group G4 having a positive refractive power, a fifth lens group G5 having a positive refractive power, and a sixth lens group G6 having a negative refractive power.
The first lens group G1 includes, in order from the object side, a cemented lens of a negative meniscus lens L11 having a convex surface facing the object side and a positive meniscus lens L12 having a convex surface facing the object side, and a positive meniscus having a convex surface facing the object side. A lens L13 and a biconvex positive lens L14 are included.
The second lens group G2 includes, in order from the object side, a negative meniscus lens L21 having a convex surface directed toward the object side, a cemented lens of a biconcave negative lens L22 and a biconvex positive lens L23, and a concave surface on the object side. And a negative meniscus lens L24 facing the lens.

The third lens group G3 includes, in order from the object side, a biconvex positive lens L31, and a cemented lens of a negative meniscus lens L32 having a convex surface facing the object side and a biconvex positive lens L33.
The fourth lens group G4 includes, in order from the object side, a negative meniscus lens L41 having a concave surface directed toward the object side, an aperture stop S, a biconvex positive lens L42, a biconvex positive lens L43, and a biconcave shape. The negative lens L44 is a cemented lens.
The fifth lens group G5 includes, in order from the object side, a negative meniscus lens L51 having a convex surface directed toward the object side, a positive meniscus lens L52 having a concave surface directed toward the object side, a positive lens L53 having a biconvex shape, and a concave surface facing the object side. Is composed of a cemented lens with a negative meniscus lens L54 facing and a fixed stop ST.
The sixth lens group G6 includes, in order from the object side, a negative meniscus lens L61 having a concave surface directed toward the object side, and a biconvex positive lens L62.

In the zoom lens according to the present embodiment, the air gap between the first lens group G1 and the second lens group G2 increases during zooming from the wide-angle end state to the telephoto end state, and the second lens group G2 and the third lens. The air gap between the group G3 decreases, the air gap between the third lens group G3 and the fourth lens group G4 increases, the air gap between the fourth lens group G4 and the fifth lens group G5 increases, The first lens group G1, the third lens group G3, the fourth lens group G4, the fifth lens group G5, and the sixth lens group G6 are arranged so that the air gap between the lens group G5 and the sixth lens group G6 decreases. Moving to the object side along the optical axis, the position of the second lens group G2 is fixed. At this time, the aperture stop S moves together with the fourth lens group G4, and the fixed stop ST moves together with the fifth lens group G5.
In the zoom lens according to the present embodiment, focusing from an object at infinity to a near object is performed by moving the third lens group G3 along the optical axis toward the object side.
Further, in the zoom lens according to the present embodiment, the cemented positive lens of the positive lens L53 and the negative meniscus lens L54 in the fifth lens group G5 is moved as a vibration-proof lens group so as to include a component in a direction orthogonal to the optical axis. Thus, vibration isolation is performed.

Table 4 below lists values of specifications of the zoom lens according to the present example.
Here, the zoom lens according to the present example has an anti-vibration coefficient of 0.82 and a focal length of 56.5 (mm) in the wide-angle end state. The moving amount of the vibration lens group is 0.51 (mm). Further, in the telephoto end state, since the image stabilization coefficient is 1.21 and the focal length is 292.0 (mm), the amount of movement of the image stabilization lens group for correcting the rotation blur of 0.18 ° is 0. 78 (mm).

(Table 4) Fourth Example
[Surface data]
Surface number r d nd νd
Object ∞
1) 160.017 2.000 1.954000 33.40
2) 90.969 7.799 1.497820 82.51
3) 472.500 0.100 1.000000
4) 160.494 5.211 1.497820 82.51
5) 1215.187 0.100 1.000000
6) 100.098 8.092 1.497820 82.51
7) -2301.870 Variable 1.000000
8) 162.975 1.800 1.882997 40.76
9) 36.967 10.470 1.000000
10) -56.321 1.400 1.497820 82.51
11) 50.190 5.334 1.808090 22.79
12) -292.643 2.963 1.000000
13) -48.151 1.400 1.825516 44.83
14) -120.551 Variable 1.000000
15) 117.239 4.142 1.754998 52.32
16) -407.716 0.100 1.000000
17) 67.401 1.400 1.903660 31.27
18) 39.783 8.366 1.497820 82.51
19) -227.261 Variable 1.000000
20) -58.662 1.400 1.725422 33.05
21) -107.934 1.000 1.000000
22) (Aperture S) ∞ 0.100 1.000000
23) 50.922 6.728 1.741135 37.98
24) -288.588 0.100 1.000000
25) 63.091 5.265 1.497820 82.51
26) -300.145 1.400 1.903660 31.27
27) 82.193 Variable 1.000000
28) 251.927 1.400 1.882997 40.76
29) 39.120 3.880 1.000000
30) -72.546 2.390 1.846660 23.78
31) -49.010 2.000 1.000000
32) 37.490 5.794 1.497820 82.51
33) -81.828 1.000 1.853338 34.91
34) -247.964 2.000 1.000000
35) (Aperture ST) ∞ Variable 1.000000
36) -30.850 1.400 1.882997 40.76
37) -74.137 0.100 1.000000
38) 112.106 3.029 1.846660 23.78
39) -498.834 BF 1.000000
Image plane ∞

[Various data]
Scaling ratio 5.17
W M T
f 56.50 105.00 291.99
FNO 2.88 3.40 4.12
2ω 43.55 23.19 8.34
Y 21.60 21.60 21.60
TL 231.08 255.19 287.70
BF 38.47 57.59 70.93

W M T
d7 2.000 26.107 58.613
d14 46.606 30.599 2.400
d19 13.783 11.335 26.130
d27 17.335 19.248 19.613
d35 13.229 10.651 10.344

[Zoom lens group data]
Group start surface f
1 1 130.386
2 8 -31.967
3 15 73.757
4 20 119.645
5 28 562.270
6 36 -143.421

[Conditional expression values]
(1) f1 / fRw = 0.54
(2) f2 / f3 = 0.43
(3) f3 / fRw = 0.30
(4) f1 / f3 = 1.77

11 (a), 11 (b), and 11 (c) respectively show the infinite object combination in the wide-angle end state, the intermediate focal length state, and the telephoto end state of the zoom lens according to Example 4 of the present application. FIG. 5 is a diagram showing various aberrations during focusing.
12 (a) and 12 (b) respectively perform image stabilization against 0.42 ° rotation blur when focusing on an object at infinity in the wide-angle end state of the zoom lens according to Example 4 of the present application. FIG. 6 is a meridional lateral aberration diagram when the object is in focus, and a meridional lateral aberration diagram when the image stabilization is performed with respect to a rotational shake of 0.18 ° when focusing on an object at infinity in the telephoto end state.
From each aberration diagram, the zoom lens according to the present embodiment has excellent imaging performance by correcting various aberrations well from the wide-angle end state to the telephoto end state, and also has excellent imaging performance during image stabilization. It can be seen that

(5th Example)
FIG. 13 is a cross-sectional view showing the configuration and zoom trajectory of the zoom lens according to Example 5 of the present application.
The zoom lens according to the present embodiment includes, in order from the object side, a first lens group G1 having a positive refractive power, a second lens group G2 having a negative refractive power, and a third lens group having a positive refractive power. G3 and a fourth lens group G4 having a positive refractive power.
The first lens group G1 includes, in order from the object side, a cemented lens of a negative meniscus lens L11 having a convex surface facing the object side and a positive meniscus lens L12 having a convex surface facing the object side, and a positive meniscus having a convex surface facing the object side. A lens L13 and a biconvex positive lens L14 are included.
The second lens group G2 includes, in order from the object side, a negative meniscus lens L21 having a convex surface directed toward the object side, a cemented lens of a biconcave negative lens L22 and a biconvex positive lens L23, and a concave surface on the object side. And a negative meniscus lens L24 facing the lens.

The third lens group G3 includes, in order from the object side, a cemented lens of a negative meniscus lens L31 having a convex surface directed toward the object side and a biconvex positive lens L32, and a biconvex positive lens L33.
The fourth lens group G4 includes, in order from the object side, a first partial group G41, a second partial group G42, a fixed stop ST, and a third partial group G43.
The first partial group G41 includes, in order from the object side, a cemented lens of a biconvex positive lens L41 and a negative meniscus lens L42 having a concave surface facing the object side, an aperture stop S, and a biconcave negative lens L43. , A biconvex positive lens L44, a biconcave negative lens L45, and a positive meniscus lens L46 having a concave surface facing the object side.
The second partial group G42 includes, in order from the object side, a cemented lens of a biconvex positive lens L47 and a negative meniscus lens L48 having a concave surface facing the object side.
The third partial group G43 includes, in order from the object side, a negative meniscus lens L49 having a concave surface directed toward the object side, and a biconvex positive lens L410.

In the zoom lens according to the present embodiment, the air gap between the first lens group G1 and the second lens group G2 increases during zooming from the wide-angle end state to the telephoto end state, and the second lens group G2 and the third lens. The first lens group G1, the third lens group G3, and the fourth lens group G4 are arranged so that the air gap between the group G3 decreases and the air gap between the third lens group G3 and the fourth lens group G4 increases. Moving to the object side along the optical axis, the second lens group G2 moves along the optical axis. At this time, the aperture stop S and the fixed stop ST move together with the fourth lens group G4.
In the zoom lens according to the present embodiment, focusing from an object at infinity to a near object is performed by moving the third lens group G3 along the optical axis toward the object side.
In the zoom lens according to the present embodiment, image stabilization is performed by moving the second partial group G42 having positive refractive power as an image stabilization lens group so as to include a component in a direction orthogonal to the optical axis.

Table 5 below provides values of specifications of the zoom lens according to the present example.
Here, the zoom lens according to the present example has an anti-vibration coefficient of 0.80 and a focal length of 56.5 (mm) in the wide-angle end state. The movement amount of the vibration lens group is 0.52 (mm). In the telephoto end state, since the image stabilization coefficient is 1.18 and the focal length is 292.0 (mm), the movement amount of the image stabilization lens group for correcting the rotation blur of 0.18 ° is 0. 80 (mm).

(Table 5) Fifth Example
[Surface data]
Surface number r d nd νd
Object ∞
1) 155.150 2.000 1.954000 33.40
2) 83.541 8.764 1.497820 82.51
3) 561.415 0.100 1.000000
4) 114.668 6.945 1.497820 82.51
5) 1249.811 0.100 1.000000
6) 93.156 8.414 1.497820 82.51
7) -5594.760 Variable 1.000000
8) 157.493 1.800 1.882997 40.76
9) 35.647 10.918 1.000000
10) -55.238 1.400 1.497820 82.51
11) 48.581 5.461 1.808090 22.79
12) -519.336 3.689 1.000000
13) -44.694 1.400 1.754510 52.35
14) -94.806 Variable 1.000000
15) 66.468 1.400 1.903660 31.27
16) 44.012 8.590 1.497820 82.51
17) -206.531 0.100 1.000000
18) 161.905 3.554 1.688349 56.69
19) -564.598 Variable 1.000000
20) 106.936 5.785 1.497820 82.51
21) -101.453 1.400 1.903660 31.27
22) -224.1515 0.100 1.000000
23) (Aperture S) ∞ 2.999 1.000000
24) -98.602 1.400 1.881929 39.96
25) 497.415 0.100 1.000000
26) 45.272 7.006 1.702135 38.94
27) -391.474 17.847 1.000000
28) -96.201 1.400 1.870537 32.92
29) 50.883 3.809 1.000000
30) -72.046 3.017 1.846660 23.78
31) -40.636 2.000 1.000000
32) 41.826 6.177 1.497820 82.51
33) -68.512 1.000 1.874587 35.14
34) -192.031 4.145 1.000000
35) (Aperture ST) ∞ 15.726 1.000000
36) -29.829 1.400 1.882625 40.48
37) -72.533 0.100 1.000000
38) 99.262 3.384 1.745746 27.57
39) -327.293 BF 1.000000
Image plane ∞

[Various data]
Scaling ratio 5.17
W M T
f 56.50 105.00 292.00
FNO 2.88 3.40 4.12
2ω 43.43 23.17 8.36
Y 21.60 21.60 21.60
TL 248.98 266.71 288.06
BF 38.47 54.65 68.59

W M T
d7 2.000 20.891 44.965
d14 56.426 37.428 2.400
d19 8.656 10.308 28.682

[Zoom lens group data]
Group start surface f
1 1 110.869
2 8 -31.300
3 15 83.089
4 20 270.025

[Conditional expression values]
(1) f1 / fRw = 0.41
(2) f2 / f3 = 0.38
(3) f3 / fRw = 0.31
(4) f1 / f3 = 1.33

FIGS. 14 (a), 14 (b), and 14 (c) respectively show the object at infinity in the wide-angle end state, the intermediate focal length state, and the telephoto end state of the zoom lens according to Example 5 of the present application. FIG. 5 is a diagram showing various aberrations during focusing.
FIGS. 15 (a) and 15 (b) each perform vibration isolation against 0.42 ° rotation blur when focusing on an object at infinity in the wide-angle end state of the zoom lens according to Example 5 of the present application. FIG. 6 is a meridional lateral aberration diagram when the object is in focus, and a meridional lateral aberration diagram when the image stabilization is performed with respect to a rotational shake of 0.18 ° when focusing on an object at infinity in the telephoto end state.
From each aberration diagram, the zoom lens according to the present embodiment has excellent imaging performance by correcting various aberrations well from the wide-angle end state to the telephoto end state, and also has excellent imaging performance during image stabilization. It can be seen that

According to each of the above embodiments, it is possible to realize a telephoto anti-vibration zoom lens that has a bright F-number of 2.8 to 4.0, a large zoom ratio of about 5 times, and high optical performance. Can do.
Here, each said Example has shown one specific example of this invention, and this invention is not limited to these.
Note that the following contents can be adopted as appropriate as long as the optical performance of the zoom lens of the present application is not impaired.
As a numerical example of the zoom lens of the present application, a four-group or six-group configuration is shown, but the present application is not limited to this, and a zoom lens of other group configuration (for example, 5 group, 7 group, etc.) is configured. You can also. Specifically, a configuration in which a lens or a lens group is added to the most object side or the most image plane side of the zoom lens of the present application may be used. The lens group refers to a portion having at least one lens separated by an air interval that changes during zooming.

In addition, the zoom lens of the present application is used in order to focus from an object at infinity to an object at a short distance in the direction of the optical axis using a part of the lens group, the entire lens group, or a plurality of lens groups as the focusing lens group. It is good also as a structure moved to. In particular, it is preferable that at least a part of the third lens group is a focusing lens group. Such a focusing lens group can also be applied to autofocus, and is also suitable for driving by an autofocus motor, such as an ultrasonic motor.
In the zoom lens of the present application, either the entire lens group or a part thereof is moved so as to include a component perpendicular to the optical axis as an anti-vibration lens group, or rotated in an in-plane direction including the optical axis ( The image blur caused by camera shake or the like can be corrected by swinging). In particular, in the zoom lens of the present application, it is preferable that at least a part of the fourth lens group is an anti-vibration lens group.

  The lens surface of the lens constituting the zoom lens of the present application may be a spherical surface, a flat surface, or an aspheric surface. When the lens surface is a spherical surface or a flat surface, it is preferable because lens processing and assembly adjustment are easy, and deterioration of optical performance due to errors in lens processing and assembly adjustment can be prevented. Further, even when the image plane is deviated, it is preferable because there is little deterioration in drawing performance. When the lens surface is aspherical, any of aspherical surface by grinding, glass mold aspherical surface in which glass is molded into an aspherical shape, or composite aspherical surface in which resin provided on the glass surface is formed in an aspherical shape Good. The lens surface may be a diffractive surface, and the lens may be a gradient index lens (GRIN lens) or a plastic lens.

In the zoom lens of the present application, the aperture stop is preferably arranged in or near the fourth lens group. However, a lens frame may be used as a substitute for the aperture stop without providing a member.
Further, an antireflection film having a high transmittance in a wide wavelength range may be provided on the lens surface of the lens constituting the zoom lens of the present application. Thereby, flare and ghost can be reduced, and high optical performance with high contrast can be achieved.
The zoom lens of the present application has a zoom ratio of about 3 to 10 times.

Next, a camera equipped with the zoom lens of the present application will be described with reference to FIG.
FIG. 16 is a diagram illustrating a configuration of a camera including the zoom lens of the present application.
The camera 1 is a digital single-lens reflex camera provided with the zoom lens according to the first embodiment as a photographing lens 2.
In the camera 1, light from an object (subject) (not shown) is collected by the taking lens 2 and imaged on the focusing screen 4 through the quick return mirror 3. The light imaged on the focusing screen 4 is reflected in the pentaprism 5 a plurality of times and guided to the eyepiece lens 6. Thus, the photographer can observe the subject image as an erect image through the eyepiece 6.

When the release button (not shown) is pressed by the photographer, the quick return mirror 3 is retracted out of the optical path, and light from the subject (not shown) reaches the image sensor 7. Thereby, the light from the subject is picked up by the image pickup device 7 and recorded as a subject image in a memory (not shown). In this way, the photographer can shoot the subject with the camera 1.
Here, the zoom lens according to the first embodiment mounted as the photographing lens 2 in the camera 1 is bright as described above, has a large zoom ratio, and has high optical performance. As a result, the camera 1 is bright, has a large zoom ratio, and can achieve high optical performance. Even if the camera having the zoom lens according to the second to fifth embodiments mounted as the taking lens 2 is configured, the same effect as the camera 1 can be obtained. Even when the zoom lens according to each of the above embodiments is mounted on a camera having no quick return mirror 3, the same effect as the camera 1 can be obtained.

Finally, the outline of the manufacturing method of the zoom lens of this application is demonstrated based on FIG.
FIG. 17 is a diagram showing a method for manufacturing the zoom lens of the present application.
The zoom lens manufacturing method of the present application includes, in order from the object side, a first lens group having a positive refractive power, a second lens group having a negative refractive power, and a third lens group having a positive refractive power; A method of manufacturing a zoom lens having a fourth lens group, which includes the following steps S1 to S4.
Step S1: By providing a known moving mechanism in the lens barrel, the magnification between the wide-angle end state and the telephoto end state, the distance between the first lens group and the second lens group, the second lens group, and the third lens group are changed. The distance between the lens groups and the distance between the third lens group and the fourth lens group are changed.
Step S2: By providing a known moving mechanism in the lens barrel, at least a part of the lens group located on the image side of the third lens group has a component in a direction perpendicular to the optical axis as an anti-vibration lens group. Move to include.
Step S3: The anti-vibration lens group has a positive refractive power.

Step S4: The lens groups are arranged in the lens barrel so that each lens group satisfies the following conditional expressions (1) and (2).
(1) 0.20 <f1 / fRw <0.80
(2) 0.25 <f2 / f3 <0.60
However,
fRw: focal length f1 of the entire lens located on the image side of the third lens group at the wide-angle end state f1: focal length f2 of the first lens group: focal length f3 of the second lens group: focal length of the third lens group According to the zoom lens manufacturing method of the present application, it is possible to manufacture a zoom lens that is bright, has a large zoom ratio, and has high optical performance.

G1 1st lens group G2 2nd lens group G3 3rd lens group G4 4th lens group G41 1st partial group G42 2nd partial group G43 3rd partial group G5 5th lens group G6 6th lens group S Aperture stop ST Fixed Aperture I Image plane W Wide-angle end state T Telephoto end state

Claims (11)

In order from the object side, a first lens group having a positive refractive power, a second lens group having a negative refractive power, a third lens group having a positive refractive power, and a fourth lens group,
Upon zooming from the wide-angle end state to the telephoto end state, the distance between the first lens group and the second lens group, the distance between the second lens group and the third lens group, and the third lens group and the first lens group The distance between the 4 lens groups changes,
The lens unit positioned on the image side of the third lens unit moves so as to include a component in a direction orthogonal to the optical axis as an anti-vibration lens unit,
The anti-vibration lens group has a positive refractive power;
A zoom lens satisfying the following conditional expression:
0.20 <f1 / fRw <0.80
0.25 <f2 / f3 <0.60
However,
fRw: focal length f1 of the entire lens located on the image side of the third lens group at the wide-angle end state: focal length f2 of the first lens group: focal length f3 of the second lens group: third lens group Focal length   The zoom lens according to claim 1, wherein the fourth lens group has a positive refractive power.   3. The zoom lens according to claim 1, wherein the first lens unit moves toward the object side upon zooming from the wide-angle end state to the telephoto end state.   4. The zoom lens according to claim 1, wherein the fourth lens unit moves toward the object side upon zooming from the wide-angle end state to the telephoto end state. 5.   The zoom lens according to any one of claims 1 to 4, wherein the third lens group is moved to perform focusing from an object at infinity to an object at a short distance. The zoom lens according to any one of claims 1 to 5, wherein the following conditional expression is satisfied.
0.20 <f3 / fRw <0.50
However,
fRw: focal length in the wide-angle end state of the entire lens located on the image side of the third lens group f3: focal length of the third lens group   The zoom lens according to any one of claims 1 to 6, wherein the anti-vibration lens group includes a cemented lens of one positive lens and one negative lens. The zoom lens according to any one of claims 1 to 7, wherein the following conditional expression is satisfied.
1.00 <f1 / f3 <2.20
However,
f1: Focal length of the first lens group f3: Focal length of the third lens group   9. The zoom lens according to claim 1, wherein lens surfaces of all the lenses in the zoom lens are spherical surfaces or flat surfaces. 10.   An optical apparatus comprising the zoom lens according to any one of claims 1 to 9. A zoom lens having, in order from the object side, a first lens group having a positive refractive power, a second lens group having a negative refractive power, a third lens group having a positive refractive power, and a fourth lens group A manufacturing method of
Upon zooming from the wide-angle end state to the telephoto end state, the distance between the first lens group and the second lens group, the distance between the second lens group and the third lens group, and the third lens group and the first lens group The distance between the four lens groups changes,
And at least a part of the lens group positioned on the image side of the third lens group moves so as to include a component in a direction orthogonal to the optical axis as a vibration-proof lens group,
The anti-vibration lens group has a positive refractive power,
A zoom lens manufacturing method characterized by satisfying the following conditional expression:
0.20 <f1 / fRw <0.80
0.25 <f2 / f3 <0.60
However,
fRw: focal length f1 of the entire lens located on the image side of the third lens group at the wide-angle end state: focal length f2 of the first lens group: focal length f3 of the second lens group: third lens group Focal length

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