JP2002162565A - Zoom lens and optical equipment using the same - Google Patents

Abstract

PROBLEM TO BE SOLVED: To obtain a zoom lens and optical equipment using the zoom lens constituted, so that a static image can be obtained by optically correcting the blur of a photographic image, caused when the zoom lens is vibrated. SOLUTION: This zoom lens is provided with a 1st lens group having negative refractive power, a 2nd lens group having positive refractive power, a 3rd lens group having positive refractive power and a 4th lens group having negative refractive power in the order starting from the object side. In the case of zooming from a wide-angle end to a telephoto end, the respective lens groups are moved on an optical axis, so that the space between the 1st and the 2nd lens groups becomes wide, the space between the 2nd and the 3rd lens groups becomes wide, and space between the 3rd and the 4th lens groups becomes narrow. A lens group which is a part of the 2nd lens group and having positive refractive power is moved, so as to have a component in the direction perpendicular to an optical axis, so that an image-forming position is displaced.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a zoom lens and an optical apparatus using the same, and more particularly to a zoom lens in which a part of a lens group of an optical system is moved so as to have a component perpendicular to an optical axis. Suitable for optical equipment such as a silver halide photographic camera, video camera, electronic still camera, digital camera, etc., which has high optical performance and excellently corrects image blurring (image blurring) when the zoom lens vibrates (tilts). Things.

[0002]

2. Description of the Related Art In recent years, various types of zoom lenses having optical means for correcting image blur caused by camera shake or the like have been proposed as photographic lenses or video lenses for the purpose of improving image quality and expanding photographing conditions. For example, JP-A-9-2302
In Japanese Patent Publication No. 36, a third lens group is divided into a positive lens group and a positive lens group by a four-unit zoom lens composed of lens units having positive, negative, positive, and positive refractive power from the object side. It has been proposed to perform image blur correction by moving the group in a direction perpendicular to the optical axis. Also, JP-A-10-232420
In the official gazette, the zoom lens for video is positive, negative,
The first and third lens units are fixed during zooming with a four-unit zoom lens unit including positive and positive refractive power lens units.
It has been proposed to perform image blur correction by separating a lens group into lens groups having positive and negative refractive powers and moving one of the lens groups in a direction perpendicular to the optical axis.

Japanese Patent Application Laid-Open No. Hei 5-232410 discloses a zoom lens having four lens units of first to fourth groups having positive, negative, positive, and positive refractive power in order from the object side.
The image blur correction is performed by moving the second lens unit in a direction perpendicular to the optical axis.

[0004]

Generally, in an optical system for correcting image blur by decentering a part of the lens of the photographing system in a direction perpendicular to the optical axis, it is relatively easy to correct the image blur. Although there is an advantage that it can be performed, there is a problem that a driving means for a lens to be moved is required, and the amount of eccentric aberration generated during image stabilization increases.

For example, if the correction optical system for correcting image blur has a large number of lens components and is heavy, a large torque is required for electric driving. In addition, if the correction lens group for correcting image blur is not appropriately set, it is necessary to increase the amount of movement of the correction optical system in order to obtain a certain amount of image blur correction effect, and the entire optical system becomes There is a problem that it becomes larger.

On the other hand, if the effect of correcting the image with respect to the movement of the correction optical system is strengthened, the imaging displacement effect becomes too sensitive to the eccentricity in order to perform accurate correction for a certain image blur correction. Therefore, it becomes difficult to perform accurate lens movement control.

According to the present invention, by appropriately arranging a correction optical system for image blur correction, a correction optical system for reducing the size of the correction optical system and maintaining a certain amount of image blur correction while maintaining high image quality. It is an object of the present invention to provide a zoom lens capable of easily controlling the amount of movement of the system and easily driving the correction optical system electrically, and an optical apparatus using the same.

[0008]

According to a first aspect of the present invention, there is provided a zoom lens having a first lens unit having a negative refractive power, a second lens unit having a positive refractive power, and a third lens unit having a positive refractive power. A lens unit having a fourth lens unit having a negative refractive power, wherein a distance between the first lens unit and the second lens unit is large when zooming from a wide-angle end to a telephoto end; Each lens group is moved on the optical axis so that the distance between the groups is wide and the distance between the third lens group and the fourth lens group is narrow, and some of the lens groups having positive refractive power in the second lens group Is moved so as to have a component in the direction perpendicular to the optical axis, thereby shifting the imaging position.

According to a second aspect of the present invention, in the first aspect, the second lens group includes, in order from the object side, a twenty-first lens group having a positive refractive power and a twenty-second lens group having a positive refractive power. The imaging position is displaced by moving the 22nd lens group so as to have a component perpendicular to the optical axis.

In a third aspect of the present invention, in the second aspect, the radius of curvature of the lens surface closest to the image plane in the twenty-first lens group is R21b, and the radius of curvature of the lens surface closest to the object in the twenty-second lens group. Is R22a, | (R21b-R22a) / (R21b + R22a) | <
0.7 is satisfied.

In a fourth aspect of the present invention, the focal length of the entire system at the wide-angle end is Fw, the focal length of the second lens group is F2, and the focal length of the twenty-second lens group is the wide-angle end. Is defined as F22, a conditional expression 0.3 <F2 / Fw <2.0 0.1 <F2 / F22 <0.7 is satisfied.

[0012] The invention of claim 5 is the invention of claim 1, 2, 3, or 4.
In the present invention, when the focal length of the i-th lens unit is Fi and the focal length of the entire system at the wide-angle end is Fw, 0.2 <| F1 / Fw | <6.0 0.6 <F3 / Fw <1 .5 0.3 <| F4 / Fw | <0.8.

According to a sixth aspect of the present invention, in any one of the first to fifth aspects of the present invention, the imaging position is displaced for correcting image blur.

According to a seventh aspect of the present invention, there is provided a zoom lens having a first lens unit having a negative refractive power, a second lens unit having a positive refractive power, a third lens unit having a positive refractive power, and a negative lens unit. A fourth lens group having a refractive power, and at the time of zooming from the wide-angle end to the telephoto end, the distance between the first lens group and the second lens group is wide, and the distance between the second lens group and the third lens group is large. Broadly, the third
A zoom lens for moving each lens group on the optical axis such that the distance between the lens group and the fourth lens group is reduced, wherein the second lens group is a twenty-first lens having a positive refractive power in order from the object side. A second lens group having a positive refractive power,
The second lens group is moved so as to have a component in the direction perpendicular to the optical axis to correct image blurring when the zoom lens vibrates, and the twenty-first lens group has a meniscus shape with a convex surface facing the object side. The 22nd lens group is composed of a cemented lens of a positive lens and a negative lens or a cemented lens of a negative lens and a positive lens, and has a radius of curvature of the lens surface closest to the image plane of the 21st lens group. R21b, the radius of curvature of the most object side lens surface of the 22nd lens group is R22a,
The focal length of the entire system at the wide-angle end is Fw, the focal length of the second lens group is F2, and the focal length of the 22nd lens group is F22.
| (R21b-R22a) / (R21b + R22a) | <
It is characterized by satisfying the condition of 0.7 0.3 <F2 / Fw <2.0 0.1 <F2 / F22 <0.7.

According to an eighth aspect of the present invention, when the focal length of the i-th lens unit is Fi and the focal length of the entire system at the wide-angle end is Fw, 0.2 <| F1 / Fw | < It is characterized by satisfying the following condition: 6.0 0.6 <F3 / Fw <1.5 0.3 <| F4 / Fw | <0.8.

According to a ninth aspect of the present invention, an optical apparatus uses the zoom lens according to any one of the first to eighth aspects.

[0017]

Embodiments of the present invention will be described below with reference to the drawings.

FIG. 1 is a sectional view of a zoom lens of Numerical Example 1 at a wide angle end, which will be described later. FIGS. 2, 3, and 4 show a zoom lens of Numerical Example 1 at a wide angle end, an intermediate zoom position, and
FIGS. 5, 6, and 7 are longitudinal aberration diagrams at the telephoto end, and FIGS. 5, 6, and 7 are lateral aberration diagrams of the zoom lens according to Numerical Example 1 at the wide-angle end, the intermediate zoom position, and the image position at the telephoto end before displacement. 10
FIG. 6 is a lateral aberration diagram after performing an image position displacement equivalent to 0.3 ° of the angle of view at the wide angle end, the intermediate zoom position, and the telephoto end of the zoom lens according to Numerical Example 1.

FIG. 11 is a sectional view of a zoom lens of Numerical Example 2 at a wide-angle end, which will be described later. FIGS. 12, 13, and 14 show a zoom lens of Numerical Example 2 at a wide-angle end, an intermediate zoom position, and a telephoto end. FIGS. 15, 16, and 17 are lateral aberration diagrams of the zoom lens of Numerical Example 2 at the wide-angle end, the intermediate zoom position, and the telephoto end before image position displacement, and FIGS.
8, 19, and 20 are lateral aberration diagrams of the zoom lens according to Numerical Example 2 after image position displacement equivalent to 0.3 ° of the angle of view at the wide-angle end, the middle position, and the telephoto end.

FIG. 21 is a sectional view of a zoom lens of Numerical Example 3 to be described later at the wide-angle end, and FIGS. 22, 23, and 24 show the zoom lens of Numerical Example 3 at the wide-angle end, intermediate zoom position, and telephoto end. FIGS. 25, 26, and 27 are lateral aberration diagrams of the zoom lens according to Numerical Example 3 at the wide-angle end, the intermediate zoom position, and the telephoto end before image position displacement, and FIGS.
8, FIG. 29, and FIG. 30 are lateral aberration diagrams of the zoom lens of Numerical Example 3 after image position displacement corresponding to 0.3 ° of the angle of view at the wide-angle end, the middle, and the telephoto end.

FIG. 31 is a sectional view of a zoom lens of Numerical Embodiment 4 to be described later at the wide-angle end, and FIGS. 32, 33 and 34 show the zoom lens of Numerical Embodiment 4 at the wide-angle end, intermediate zoom position, and telephoto end. FIG. 35, FIG. 36, and FIG. 37 are lateral aberration diagrams of the zoom lens of Numerical Example 4 at the wide angle end, the intermediate zoom position, and the telephoto end before image position displacement, and FIG.
8, FIG. 39, and FIG. 40 are lateral aberration diagrams of the zoom lens of Numerical Example 4 after image position displacement corresponding to 0.3 ° of the angle of view at the wide-angle end, middle, and telephoto ends.

In the lens sectional views of the numerical examples, L1 denotes a first group (first lens group) having a negative refractive power, L2 denotes a second group (second lens group) having a positive refractive power, and L3 denotes a positive lens. L4 represents a fourth group (fourth lens group) having a negative refractive power. The second lens unit L2 includes a second lens unit having a positive refractive power.
It has one lens unit L21 and a 22nd lens unit L22 having a positive refractive power as a correction optical system. SP is 2nd group and 3rd group
An aperture provided between the lens group and IP is an image plane.

In the present embodiment, when zooming from the wide-angle end to the telephoto end, the first position is indicated by an arrow in the sectional view of the lens.
The distance between the lens unit L1 and the second lens unit L2 increases,
Each lens unit is moved to the object side so that the distance between the lens unit L2 and the third lens unit L3 increases and the distance between the third lens unit L3 and the fourth lens unit L4 decreases.

The second lens unit L2 includes, in order from the object side, a 21st lens unit L21 having a positive refractive power and a 22nd lens unit L22 having a positive refractive power. By moving the zoom lens in a direction perpendicular to the axis, the image blur when the zoom lens vibrates is corrected.

In the present embodiment, a rear-focus type in which the third lens unit L3 is moved in the optical axis direction to perform focusing is used. The aperture stop SP moves integrally with the third lens unit during zooming.

A lens group having a positive, positive, and negative refractive power generally used in a photographing system of a lens shutter camera.
The group zoom lens mainly performs a zooming operation by changing the air gap between the second lens group having a positive refractive power and the third lens group having a negative refractive power, and further has a positive refractive power as it goes to the telephoto side. 1
It is characterized in that a further zooming action is performed by narrowing the air gap between the lens group and the second lens group having a positive refractive power, and at the same time, a field curvature fluctuation at the time of zooming is corrected.

However, in achieving a zoom lens with a higher zoom ratio, chromatic aberration fluctuation during zooming becomes a problem. Therefore, in order to obtain good image quality, it is necessary to reduce the amount of chromatic aberration generated in each lens group in order to maintain a good correction relation of chromatic aberration generated in each lens group. To properly correct chromatic aberration in each lens group, it is necessary to increase the number of lenses. For this reason, it is difficult to meet the demands for downsizing the lens system and reducing the number of lenses.

In the present invention, when changing the magnification from the wide-angle end to the telephoto end, the zooming is effectively performed by moving each lens unit as described above.

Further, in the present invention, in addition to the above-described zooming operation, the first lens unit having a positive refractive power of the three-unit zoom lens including a lens unit having positive, positive and negative refractive powers is replaced with a lens unit having a negative refractive power. And two lens groups of positive refractive power,
At the time of zooming, the chromatic aberration fluctuation at the time of zooming is corrected by changing the air gap between the two lens groups, and an optical system with good image quality is achieved with a small number of lenses.

Further, by moving (eccentric) the 22nd lens unit L22 having a positive refractive power in the second lens unit in the direction perpendicular to the optical axis, the imaging position is displaced, and the second lens unit is displaced. By arranging a lens unit having a positive refractive power other than the 22nd lens unit, various aberrations caused by the eccentricity of the 22nd lens unit are canceled, and at the same time, the imaging position displacement amount with respect to a constant eccentric amount of the 22nd lens unit And it is easy to obtain the optimum amount of movement for the electric drive of the 22nd lens group.

At this time, the second lens group is formed by disposing a 21st lens group having a positive refractive power on the object side of the 22nd lens group, and performing eccentric movement of the 22nd lens group with respect to the optical axis. Performing image position displacement is good for aberration correction. Thereby, the convergence of the 21st lens group having a positive refractive power controls the angle of light rays incident on the 22nd lens group, thereby easily controlling the amount of aberration change due to the eccentricity of the 22nd lens group, and at the same time, the 22nd lens. The size of the lens system of the group is reduced, and at the same time, the size of the moving mechanism system of the 22nd lens group is easily achieved.

The zoom lens according to the present invention is realized by adopting the above-mentioned configuration. In order to achieve better optical performance, it is desirable to satisfy at least one of the following conditions.

(A-1) When the radius of curvature of the lens surface closest to the image plane in the 21st lens group is R21b, and the radius of curvature of the lens surface closest to the object in the 22nd lens group is R22a, | (R21b −R22a)) / (R21b + R22a)) | <0.7 (1)

The conditional expression (1) is a conditional expression for suppressing the deterioration of the image quality at the time of displacement of the image forming position. is there. Exceeding the numerical range of conditional expression (1) is not good because the canceling relationship between spherical aberration and coma aberration on the mutual surface when the imaging position is displaced and when there is no displacement is broken.

(A-2) When the focal length of the entire system at the wide-angle end is Fw, the focal length of the second lens group is F2, and the focal length of the 22nd lens group is F22, 0.3 <F2 / Fw < 2.0... (2) 0.1 <F2 / F22 <0.7... (3)

If the refractive power of the second lens unit is weakened beyond the upper limit value of the conditional expression (2), the total length of the lens system increases in order to secure a constant focal length and a variable power ratio. Not good. On the other hand, if the lower limit value is exceeded, the refractive power of the second lens group becomes too strong, and negative spherical aberration occurs strongly, and it is difficult for other lens groups to satisfactorily correct this in the entire zoom range. It is becoming.

Conditional expression (3) relates to the refractive power of the 22nd lens group which performs the image position displacement action in the second lens group, and the eccentric movement of the 22nd lens group for performing the constant image position displacement action. This is for maintaining high image quality while suppressing the amount. If the negative refractive power of the 22nd lens group becomes weaker beyond the upper limit of conditional expression (3), the amount of eccentric movement of the 22nd lens group becomes too large to perform a constant image position displacement action. In order to obtain a constant peripheral light amount during the eccentric movement, the lens diameter of the 22nd lens group increases, which is not good.

On the other hand, when the value exceeds the lower limit, the positive refractive power of the 22nd lens group increases and at the same time, the positive refractive power of the lens systems other than the 22nd lens group in the third lens group must be increased. In this case, high-order spherical aberration and coma aberration are largely generated, and it becomes difficult to correct aberration when the imaging position is displaced.

It is preferable that each of the 22nd lens group is composed of one positive lens and one negative lens in order to suppress the fluctuation of aberration when the lens is moved when the imaging position is displaced. It is more desirable to limit the numerical ranges of the conditional expressions (2) and (3) to the following.

0.5 <F2 / Fw <1.4 (2a) 0.18 <F2 / F22 <0.65 (3a) (A-3) The focal length of the i-th lens group is Fi, When the focal length of the entire system at the wide angle end is Fw, 0.2 <| F1 / Fw | <6.0 (6) 0.6 <F3 / Fw <1.5 (5) 3 <| F4 / Fw | <0.8 (6)

The conditional expressions (4) to (6) are mainly for achieving a high quality and compact optical system. When the value exceeds the upper limit of conditional expression (4), the negative refractive power of the first lens unit becomes too weak, which leads to an increase in the lens outer diameter and an increase in the overall length of the lens. On the other hand, if the lower limit value is exceeded, the refractive power of the first lens group becomes stronger, and high-order spherical aberrations become large, making it difficult to correct this.

When the value exceeds the upper limit of conditional expression (5), the refractive power of the third lens unit is weakened, and the amount of movement of each lens unit becomes large in order to obtain a constant zoom ratio. It becomes difficult to make the system compact. On the other hand, if the value exceeds the lower limit, the negative refractive power becomes large, so that the Petzval sum becomes large in the negative direction, and the field curvature becomes large.

When the value exceeds the upper limit of conditional expression (6), the refracting power of the fourth lens unit becomes too weak, so that the back focus becomes longer and the overall length of the lens increases, which is not good. On the other hand,
If the lower limit is exceeded, the back focus of the entire lens system becomes too short, and the outer diameter of the fourth lens group becomes large in order to obtain a constant peripheral light amount, so that the optical system becomes large. At the same time, large off-axis high-order aberrations such as field curvature are generated, which is not good.

More desirably, when the numerical range of conditional expressions (4) to (6) is limited as follows, an optical system with higher image quality can be easily achieved.

0.6 <| F1 / Fw | <4.5 (4a) 0.7 <F3 / Fw <1.2 (5a) 0.4 <| F4 / Fw | <0.7 (6a) (a-4) Focusing from an object at infinity to an object at a short distance can be performed by moving the third lens group to the object side, but focusing is performed in combination with movement of another lens group. May be.

(A-5) For zooming, for example, the second
Moving a plurality of lens groups together, such as a lens group and a fourth lens group, or a diaphragm and a fourth lens group, or a diaphragm and an arbitrary lens group during zooming is advantageous for simplifying the lens driving mechanism. .

(A-6) The iris diaphragm is on the optical axis during zooming.
The movement may be independent of each lens group. According to this, the entrance pupil position can be optimally arranged.

(A-7) In the first lens unit, in order from the object side, a positive lens having a convex surface having a stronger refractive power on the lens surface on the object side than an image surface side and a negative lens having both concave surfaces are concave. good.

(A-8) The second lens group includes, in order from the object side, a meniscus-shaped positive lens having a convex surface facing the object side;
It is preferable to use a positive lens obtained by combining a positive lens and a negative lens.

(A-9) The third lens group is composed of at least a meniscus negative lens having a concave surface facing the object side and a convex positive lens having a lens surface on the image plane side having a higher refractive power than the object side. Is good.

(A-10) It is desirable to arrange an aspherical surface in the third lens group in order to achieve good image quality.

(A-11) It is preferable that the fourth lens group has one negative lens having a strong concave surface at least on the object side.

(A-12) It is desirable for aberration correction that the fourth lens group has at least one aspheric surface.

(A-13) It is effective to further add an aspherical surface to the lens system and to introduce a diffractive optical element, a refractive index distribution type optical material, etc. in order to improve the optical performance.

As described above, according to the zoom lens of the embodiment, the imaging position is displaced by moving the positive lens group in the second lens group in the direction perpendicular to the optical axis. A compact zoom lens having a high zoom ratio that can maintain good optical performance can be achieved.

Next, an embodiment of an optical apparatus having a zoom lens according to the present invention will be described with reference to FIG. FIG.
(A) is a front view of the imaging device, and (b) of FIG. 41 is a side sectional view. In the figure, 10 is a photographing apparatus main body (housing), 11 is a photographing optical system using the zoom lens of the present invention, 12 is a finder optical system, and 13 is a film as a photosensitive surface.
As described above, by applying the zoom lens of the present invention to a photographic optical system of an optical device, a compact and high-performance optical device can be realized.

Next, numerical examples of the present invention will be described. In the numerical examples, Ri is the radius of curvature of the i-th surface in order from the object side, Di is the i-th optical member thickness or air gap in order from the object side, and Ni and νi are the i-th optical members in order from the object side. These are the refractive index and Abbe number of the material of the member.

Table 1 shows the relationship between the above-described conditional expressions and various numerical values in the numerical examples. The aspherical surface shape is the X axis in the optical axis direction, the H axis in the direction perpendicular to the optical axis, the light traveling direction is positive,
When R is the paraxial radius of curvature and K, B, C, D, and E are each aspheric coefficients.

[0059]

(Equation 1)

This is represented by the following equation. The "e-0X" means "× 10 ^-X".

[0061]

[Outside 1]

[0062]

[Outside 2]

[0063]

[Outside 3]

[0064]

[Outside 4]

[0065]

[Table 1]

[0066]

According to the present invention, by appropriately arranging the correction optical system for image blur correction, it is possible to reduce the size of the correction optical system while maintaining high image quality, and to achieve a certain amount of image blur correction effect. It is possible to achieve a zoom lens and an optical apparatus using the same, which can easily control the amount of movement of the correction optical system for performing the correction and easily perform electric driving of the correction optical system.

[Brief description of the drawings]

FIG. 1 is a lens cross-sectional view of a zoom lens according to Numerical Example 1.

FIG. 2 is a longitudinal aberration diagram at the wide-angle end of a zoom lens according to Numerical Example 1.

FIG. 3 is a longitudinal aberration diagram of the zoom lens according to Numerical Example 1 at an intermediate zoom position.

FIG. 4 is a longitudinal aberration diagram at the telephoto end of a zoom lens according to Numerical Example 1.

FIG. 5 is a lateral aberration diagram of the zoom lens according to Numerical Example 1 at the wide-angle end before zooming.

FIG. 6 is a lateral aberration diagram of the zoom lens according to Numerical Example 1 at the intermediate zoom position before zooming.

FIG. 7 is a lateral aberration diagram of the zoom lens at the telephoto end before zooming according to Numerical Example 1;

FIG. 8 is a lateral aberration diagram after performing a displacement of an image position corresponding to 0.3 ° of both angles at the wide angle end of the zoom lens according to Numerical Example 1.

FIG. 9 is a lateral aberration diagram after performing an image position displacement corresponding to 0.3 ° of both angles at an intermediate zoom position of the zoom lens according to Numerical Example 1.

FIG. 10 is a lateral aberration diagram after performing a displacement of an image position corresponding to both angles of 0.3 ° at the telephoto end of the zoom lens according to Numerical Example 1.

FIG. 11 is a sectional view of a zoom lens according to a second numerical example;

FIG. 12 is a longitudinal aberration diagram at a wide-angle end of a zoom lens according to Numerical Example 2.

FIG. 13 is a longitudinal aberration diagram of the zoom lens according to Numerical Example 2 at an intermediate zoom position.

FIG. 14 is a longitudinal aberration diagram at the telephoto end of a zoom lens according to Numerical Example 2.

FIG. 15 is a diagram showing lateral aberrations before zooming at the wide-angle end of the zoom lens according to Numerical Example 2.

FIG. 16 is a lateral aberration diagram of the zoom lens according to Numerical Example 2 at the intermediate zoom position before zooming.

FIG. 17 is a lateral aberration diagram of the zoom lens according to Numerical Example 2 at the telephoto end before zooming.

FIG. 18 is a lateral aberration diagram after performing an image position displacement corresponding to 0.3 ° of both angles at the wide angle end of the zoom lens of Numerical Example 2;

FIG. 19 is a lateral aberration diagram after performing an image position displacement corresponding to 0.3 ° of both angles at the intermediate zoom position of the zoom lens according to Numerical Example 2.

FIG. 20 is a lateral aberration diagram after performing an image position displacement corresponding to both angles of 0.3 ° at the telephoto end of the zoom lens according to Numerical Example 2;

FIG. 21 is a sectional view of a zoom lens according to Numerical Data Example 3;

FIG. 22 is a longitudinal aberration diagram at the wide-angle end of the zoom lens according to Numerical Example 3.

FIG. 23 is a longitudinal aberration diagram of the zoom lens according to Numerical Example 3 at an intermediate zoom position.

FIG. 24 is a longitudinal aberration diagram at the telephoto end of a zoom lens according to Numerical Example 3.

FIG. 25 is a lateral aberration diagram of the zoom lens according to Numerical Example 3 at the wide-angle end before zooming.

FIG. 26 is a lateral aberration diagram of the zoom lens according to Numerical Example 3 at the intermediate zoom position before zooming.

FIG. 27 is a lateral aberration diagram of the zoom lens according to Numerical Example 3 at the telephoto end before zooming.

FIG. 28 is a lateral aberration diagram after performing an image position displacement corresponding to 0.3 ° of both angles at the wide angle end of the zoom lens in Numerical Example 3;

FIG. 29 is a lateral aberration diagram after performing an image position displacement equivalent to 0.3 ° of both angles at the intermediate zoom position of the zoom lens according to Numerical Example 3;

FIG. 30 is a lateral aberration diagram after performing an image position displacement corresponding to 0.3 ° of both angles at the telephoto end of the zoom lens according to Numerical Example 3;

FIG. 31 is a sectional view of a zoom lens according to Numerical Data Example 4;

FIG. 32 is a longitudinal aberration diagram at the wide-angle end of the zoom lens according to Numerical Example 4.

FIG. 33 is a longitudinal aberration diagram of the zoom lens according to Numerical Example 4 at an intermediate zoom position.

FIG. 34 is a longitudinal aberration diagram at the telephoto end of a zoom lens according to Numerical Example 4.

FIG. 35 is a lateral aberration diagram before zooming at the wide-angle end of a zoom lens according to Numerical Example 4.

FIG. 36 is a lateral aberration diagram of the zoom lens according to Numerical Example 4 at the intermediate zoom position before zooming.

FIG. 37 is a lateral aberration diagram of the zoom lens according to Numerical Example 4 at the telephoto end before zooming.

FIG. 38 is a lateral aberration diagram after performing an image position displacement corresponding to both angles of 0.3 ° at the wide angle end of the zoom lens of Numerical Example 4;

FIG. 39 is a lateral aberration diagram after performing an image position displacement corresponding to 0.3 ° of both angles at the intermediate zoom position of the zoom lens of Numerical Example 4;

FIG. 40 is a lateral aberration diagram after performing an image position displacement corresponding to both angles of 0.3 ° at the telephoto end of the zoom lens in Numerical Example 4;

FIG. 41 is a schematic view of a main part of an optical apparatus having a zoom lens according to the present invention.

[Explanation of symbols]

 L1 First lens unit L2 Second lens unit L21 Second lens unit L22 Second lens unit L3 Third lens unit L4 Fourth lens unit SP Aperture IP image plane d d-line g g-line ΔM Meridional image plane ΔS Sagittal image plane

 ──────────────────────────────────────────────────続 き Continued on the front page F term (reference) 2H044 EF04 2H087 KA02 KA03 NA07 PA07 PA18 PA19 PB08 PB09 QA02 QA07 QA14 QA22 QA25 QA37 QA41 QA42 QA45 QA46 RA05 RA13 SA24 SA26 SA29 SA33 SA62 SA63 SB64 SB65 SB14

Claims (9)

[Claims] 1. A first lens group having a negative refractive power, a second lens group having a positive refractive power, a third lens group having a positive refractive power, and a fourth lens group having a negative refractive power are arranged in order from the object side. In zooming from the wide-angle end to the telephoto end, the distance between the first lens group and the second lens group is wide, the distance between the second lens group and the third lens group is wide, and the third lens group and the fourth lens Each lens group is moved on the optical axis so that the distance between the groups is narrowed, and some of the lens groups having a positive refractive power in the second lens group are moved so as to have a component perpendicular to the optical axis. A zoom lens characterized in that an image forming position is displaced by causing the zoom lens to move. 2. The second lens group includes, in order from the object side,
It has a 21st lens group having a positive refractive power and a 22nd lens group having a positive refractive power. By moving the 22nd lens group so as to have a component in a direction perpendicular to the optical axis, the displacement of the imaging position is reduced. The zoom lens according to claim 1, wherein the zoom lens is used. 3. When the radius of curvature of the lens surface closest to the image plane in the 21st lens group is R21b and the radius of curvature of the lens surface closest to the object in the 22nd lens group is R22a, | (R21b-R22a) ) / (R21b + R22a) | <
The zoom lens according to claim 2, wherein a condition of 0.7 is satisfied. 4. The focal length of the entire system at the wide-angle end is represented by Fw,
When the focal length of the second lens group is F2 and the focal length of the 22nd lens group is F22, the following conditional expression is satisfied: 0.3 <F2 / Fw <2.0 0.1 <F2 / F22 <0.7 4. The method according to claim 2, wherein
Zoom lens. 5. When the focal length of the i-th lens unit is Fi and the focal length of the entire system at the wide-angle end is Fw, 0.2 <| F1 / Fw | <6.0 0.6 <F3 / Fw < 4. A method according to claim 1, wherein the condition 1.5 0.3 <| F4 / Fw | <0.8 is satisfied.
Or 4 zoom lenses. 6. The zoom lens according to claim 1, wherein an image forming position is displaced for correcting image blur. 7. A first lens unit having a negative refractive power, a second lens unit having a positive refractive power, a third lens unit having a positive refractive power, and a fourth lens unit having a negative refractive power are arranged in order from the object side. When zooming from the wide-angle end to the telephoto end, the distance between the first lens group and the second lens group is wide, the distance between the second lens group and the third lens group is wide, and A zoom lens for moving each lens group on the optical axis so that the distance between the fourth lens group becomes narrower. The second lens group includes, in order from the object side, a 21st lens group having a positive refractive power, A 22nd lens group having a refractive power of, and moving the 22nd lens group so as to have a component perpendicular to the optical axis to correct image blurring when the zoom lens vibrates, and The 21st lens group includes a meniscus positive lens having a convex surface facing the object side, and the 22nd lens group. Consists of a cemented lens of a positive lens and a negative lens or a cemented lens of a negative lens and a positive lens,
The radius of curvature of the lens surface closest to the image plane in the 21st lens group is R21b, the radius of curvature of the lens surface closest to the object in the 22nd lens group is R22a, the focal length of the entire system at the wide-angle end is Fw, When the focal length of the second lens group is F2 and the focal length of the 22nd lens group is F22, | (R21b-R22a) / (R21b + R22a) | <
A zoom lens characterized by satisfying the following condition: 0.7 0.3 <F2 / Fw <2.0 0.1 <F2 / F22 <0.7 8. When the focal length of the i-th lens group is Fi and the focal length of the entire system at the wide-angle end is Fw, 0.2 <| F1 / Fw | <6.0 0.6 <F3 / Fw < 8. The zoom lens according to claim 7, wherein the following condition is satisfied: 1.5 0.3 <| F4 / Fw | <0.8. 9. An optical apparatus comprising the zoom lens according to claim 1. Description: