JP2003202497A - Zoom lens and optical equipment provided with the same - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To obtain a zoom lens wherein the generation of eccentric aberration is suppressed when a vibration proofing lens group is made in an eccentric state and the eccentric aberration is satisfactorily compensated, and to obtain optical equipment provided with the zoom lens. <P>SOLUTION: As for the zoom lens provided with a 1st lens group having a positive refractive power, a 2nd lens group, a 3rd lens group having a negative refractive power, a 4th lens group having a positive refractive power and a 5th lens group having a positive refractive power in this order from an object side, and wherein zooming is performed by moving the lens groups so that a distance between the 1st lens group and the 2nd lens group at a telephoto end may be varied from that at a wide angle end, a distance between the 2nd lens group and the 3rd lens group at the telephoto end may become longer than that at the wide angle end, and a distance between the 3rd lens group and the 4th lens group at the telephoto end may be varied from that at the wide angle end, an image is displaced by moving the 4th lens group so that it may have a component orthogonal to an optical axis. <P>COPYRIGHT: (C)2003,JPO

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, by moving a part of the lens group of the zoom lens so as to have a component in a direction perpendicular to the optical axis. The present invention is suitable for a photographic camera, a video camera, a digital camera, or the like in which a still image is obtained by optically correcting a blur of a photographed image when the lens vibrates (tilts).

[0002]

2. Description of the Related Art Generally, many photographic systems (telephoto lenses) having a long focal length are large and heavy. Therefore, it is difficult to suppress the vibration of the photographing system when using the photographing system having a long focal length. When the shooting system tilts due to vibration,
The photographed image causes a displacement (image blur) according to the tilt angle and the focal length of the photographing system. Therefore, various anti-vibration optical systems having a function of preventing the blur of a captured image have been proposed.

In general, in order to perform good image stabilization in a telephoto zoom lens having a large aperture, the size and weight of the lens group used as the image stabilization lens group are important. The vibration-proof lens group having a large diameter increases the diameter of the actuator that drives it, and the large weight increases power consumption.

A zoom lens having an image stabilizing function proposed in Japanese Patent Laid-Open No. 07-325272 has first, second, third, positive, negative, positive, and positive refracting powers in order from the object side. The second lens group, which is composed of the fourth lens group, is partially moved in a direction orthogonal to the optical axis to correct the image blur on the photographing screen.
At this time, the second lens group has a small lens diameter and has good optical performance at the time of image stabilization, but the second lens group has a high sensitivity to decentering in the tilt direction with respect to the optical axis of the second lens group, and is orthogonal to the optical axis for image stabilization. It is mechanically difficult to suppress the eccentricity in the tilt direction with respect to the optical axis while moving it in the direction of rotation. Japanese Patent Laid-Open No. 06-2892
The zoom lens having an image stabilizing function proposed in Japanese Patent Publication No. 96 is composed of first, second, third, and fourth lens groups having positive, negative, positive, and positive refractive powers in order from the object side. By moving the three lens groups in the direction orthogonal to the optical axis, the image blur on the shooting screen is corrected. Since this zoom lens has a large aperture zoom with a bright F number, it is desired to reduce the diameter and weight of the third lens group, which is a lens group for image stabilization.

[0005]

Generally, a mechanism for vibrating a part of a lens group of a photographing system to eliminate a blur of a video image and obtaining a still image has a large correction amount of the blur of the image and a mechanism for blur correction. There is a demand for a small amount of movement and rotation of a lens group (movable lens group) to be vibrated, and a small size of the entire device.

If a large amount of eccentric aberration occurs when the movable lens group is decentered, the image becomes blurred due to the eccentric aberration when the image blur is corrected. Therefore, in an optical system having a vibration isolation function, it is required that the amount of eccentric aberration generated is small when the movable lens group is moved in a direction orthogonal to the optical axis to be in an eccentric state.

According to the present invention, even though the zoom lens has a large aperture, a vibration damping system having a small diameter and a small weight of the vibration damping lens group is constructed, and good optical performance can be obtained even in a vibration-proof state. An object of the present invention is to provide a compact zoom lens and an optical device using the same.

[0008]

A zoom lens according to a first aspect of the present invention comprises, in order from the object side, a first lens group having a positive refractive power, a second lens group, a third lens group having a negative refractive power, and a positive lens group. And a fifth lens group having a positive refracting power, and the distance between the first lens group and the second lens group at the telephoto end with respect to the wide-angle end changes, A zoom lens for zooming by moving the lens group so that the distance between the lens group and the third lens group increases and the distance between the third lens group and the fourth lens group changes. Is characterized in that the image is displaced by moving so as to have a component in a direction orthogonal to the optical axis.

A zoom lens according to a second aspect of the present invention is, in order from the object side, a first lens group having a positive refractive power, a second lens group having a positive or negative refractive power, and a third lens group having a negative refractive power. It has a fourth lens group having a positive refractive power and a fifth lens group having a positive refractive power, and the distance between the first lens group and the second lens group at the telephoto end is large with respect to the wide-angle end, The distance between the lens group and the third lens group is large, the distance between the third lens group and the fourth lens group is small, and the distance between the fourth lens group and the fifth lens group is small. In a zoom lens that performs zooming by moving the third and fourth lens groups in the optical axis direction, when the fourth lens group is moved so as to have a component in a direction perpendicular to the optical axis and the zoom lens vibrates. The feature is that it corrects the blurring of the image that occurs.

According to a third aspect of the invention, in the first or second aspect of the invention, the imaging magnification at the wide angle end of the third lens group is β.
When 3w is set, it is characterized in that the condition of 0.55 <| β3w | <1.5 is satisfied.

The invention of claim 4 is the invention of claim 1, 2 or 3, wherein the combined focal length of the first lens group and the second lens group at the wide-angle end is f12W, and the focal length of the entire lens system at the wide-angle end is fw, where ft is the focal length of the entire lens system at the telephoto end,

[0012]

[Equation 2]

It is characterized in that the following condition is satisfied.

A fifth aspect of the invention is characterized in that, in the invention of any one of the first to fourth aspects, the second lens group is moved to perform focusing.

The invention of claim 6 is characterized in that, in the invention of any one of claims 1 to 5, the first lens group is fixed relative to the image plane for zooming.

The invention of claim 7 is characterized in that, in the invention of any one of claims 1 to 6, the fifth lens group is fixed relative to the image plane for zooming.

According to an eighth aspect of the present invention, in the invention according to any one of the first to seventh aspects, the fourth lens group has, in order from the object side, a positive lens and a cemented lens including a positive lens and a negative lens. I am trying.

According to a ninth aspect of the present invention, in the invention according to any one of the first to eighth aspects, the distance from the image-side surface vertex of the most image-side lens to the photographing surface is Bf, and the entire lens system at the telephoto end is represented. When the focal length is ft, it is characterized in that the condition Bf / ft> 0.25 is satisfied.

A tenth aspect of the present invention is characterized in that, in the first to ninth aspects, it is an optical system for forming an image on an image pickup device.

An eleventh aspect of the camera according to the present invention is characterized by including the zoom lens according to any one of the first to tenth aspects and an image pickup device for receiving an image formed by the zoom lens.

[0021]

1 is a sectional view of a zoom lens according to a first embodiment of the present invention at a wide-angle end, FIG. 2 is a sectional view of a zoom lens according to a first embodiment at a telephoto end, and FIGS. 5 is a lateral aberration diagram when an object at infinity is focused at the wide-angle end and the telephoto end of the zoom lens according to Embodiment 1. FIG.
(A) and (B) show a standard state (a state in which the image stabilizing lens unit is not decentered) when the object at infinity is focused at the wide-angle end of the zoom lens according to the first embodiment, and the zoom lens has 0.5.
6 Longitudinal aberration diagram when image stabilization is performed in a tilted state, Fig. 6
(A) and (B) are the standard state when focusing on an object at infinity at the telephoto end of the zoom lens of Embodiment 1 and the longitudinal aberration when image stabilization is performed with the zoom lens tilted by 0.5 °. It is a figure.

FIG. 7 is a lens cross-sectional view at the wide-angle end of the zoom lens according to the second embodiment of the present invention. FIG. 8 is a lens cross-sectional view at the telephoto end of the zoom lens according to the second embodiment.
11 is a lateral aberration diagram when an object at infinity is focused at the wide-angle end and the telephoto end of the zoom lens according to Embodiment 2, FIG.
(A) and (B) show a standard state (a state in which the anti-vibration lens unit is not decentered) when the object at infinity is focused at the wide-angle end of the zoom lens according to the second embodiment, and the zoom lens has 0.5.
12 Longitudinal aberration diagram when image stabilization is performed in a tilted state, Fig. 12
(A) and (B) are the standard state when focusing on an object at infinity at the telephoto end of the zoom lens according to the second embodiment and the longitudinal aberration when image stabilization is performed with the zoom lens tilted by 0.5 °. It is a figure.

FIG. 13 is a lens cross-sectional view at the wide-angle end of a zoom lens according to a third embodiment of the present invention, and FIG. 14 is a third embodiment.
Sectional view of the zoom lens at the telephoto end, FIG.
5 and 16 are lateral aberration diagrams when an object at infinity is focused at the wide-angle end and the telephoto end of the zoom lens according to the third embodiment, and FIGS. 17A and 17B are wide-angle views of the zoom lens according to the third embodiment. FIG. 1 is a longitudinal aberration diagram when the object is focused on an object at infinity at the end (the image stabilization lens group is not decentered) and the zoom lens is imaged with the lens tilted by 0.5 °.
8A and 8B are the vertical state when the zoom lens of Embodiment 3 is in the standard state when focused on an object at infinity at the telephoto end and when the zoom lens is image-stabilized at 0.5 °. It is an aberration diagram.

FIG. 19 is a lens cross-sectional view at the wide-angle end of the zoom lens according to the fourth embodiment of the present invention, and FIG. 20 is the fourth embodiment.
Sectional view of the zoom lens at the telephoto end, FIG.
1 and 22 are lateral aberration diagrams when an object at infinity is focused at the wide-angle end and the telephoto end of the zoom lens according to the fourth embodiment, and FIGS. 23A and 23B are wide-angle views of the zoom lens according to the fourth embodiment. FIG. 2 is a longitudinal aberration diagram when the object is focused on an object at infinity at the end (the image stabilization lens group is not decentered) and the image is imaged with the zoom lens tilted by 0.5 °.
4 (A) and 4 (B) are the vertical state when the zoom lens of Embodiment 4 is in the standard state when focused on an object at infinity at the telephoto end and when the zoom lens is shake-stabilized by 0.5 °. It is an aberration diagram.

In each lens sectional view, L1 is a first lens group having a positive refractive power, L2 is a second lens group having a positive or negative refractive power, L3 is a third lens group having a negative refractive power, and L4 is a positive lens group. And L5 is a fifth lens group having a positive refractive power.

SP is a diaphragm. IP is an image plane, on which the image pickup surface of the image pickup element and the film are located. 1st at the telephoto end (longest focal length) with respect to the wide-angle end (shortest focal length)
The distance between the lens unit L1 and the second lens unit L2 is large
The distance between the lens unit L2 and the third lens unit L3 is large,
The distance between the lens unit L3 and the fourth lens unit L4 is small,
The second lens unit L2, the third lens unit L3, and the fourth lens unit L4 are moved toward the image plane side as indicated by arrows in the lens cross-sectional views so that the distance between the lens unit L4 and the fifth lens unit L5 becomes small. Zooming from the wide-angle end to the telephoto end.

The first lens unit L1 and the fifth lens unit L5 are fixed for zooming. The fourth lens unit L4 is moved so as to have a component in the direction perpendicular to the optical axis, for example, in the direction perpendicular to the optical axis to correct image blur that occurs when the zoom lens vibrates. Focusing is performed by moving the second lens unit L2 in the optical axis direction.

The zoom position at the wide-angle end and the telephoto end is the zoom position when the zoom lens group is located at both ends of the mechanically movable range on the optical axis.

Next, the features of the zoom lens of each embodiment will be described.

In the zoom lens of each embodiment, the third lens unit L3 having a negative refracting power is moved to the image side to be multiplied, and the variation of the image point caused thereby is mainly changed to the fourth lens having a positive refracting power. The correction is performed by moving the lens unit L4.

The first lens unit L1 having a positive refracting power and the second lens unit L2 having a positive refracting power reduce the height of the light beam bundle that determines the F number, thereby forming a fourth vibration-proof lens unit. This contributes to the reduction of the lens outer diameter of the lens unit L4. In addition, the second lens unit L2 zooms from the wide-angle end to the telephoto end.
By moving to the image side during (zooming), the lens outer diameter of the second lens unit L2 is reduced, and the weight is reduced, which is advantageous for autofocusing. It is also possible to use the third lens group having a negative refracting power as the image stabilizing lens group, but it is more sensitive to tilting with respect to the optical axis than the fourth lens group L4 and is perpendicular to the optical axis during image stabilization. It is not easy to suppress the eccentricity in the falling direction when moving in the direction. In that respect, the fourth lens unit L4 is suitable as a vibration-proof lens unit because the tilt sensitivity with respect to the optical axis is smaller than that of the third lens unit L3. If the lens on the image side of the fourth lens unit L4 has an image stabilizing function, the number of lenses on the image side of the image stabilizing lens unit must be increased in order to correct various aberrations generated in the image stabilizing lens unit. Good optical performance cannot be obtained.

Therefore, in the present embodiment, the fourth lens unit L
4 is used for anti-vibration.

In this embodiment, the fourth lens unit L for image stabilization is provided.
Reference numeral 4 has a positive lens and a cemented lens composed of a positive lens and a negative lens.

When the fourth lens unit L4 is moved so as to have a component in the direction orthogonal to the optical axis to obtain a vibration-proof effect, various aberrations generated by the fourth lens unit L4 itself are not sufficiently corrected. Aberration correction by the lens on the image side of the lens unit L4 also becomes difficult. It is desirable to suppress the occurrence of chromatic aberration in the fourth lens unit L4 as much as possible. Therefore, the fourth lens unit L4
The chromatic aberration is corrected by providing a cemented lens in the. It is also desired to correct a sufficiently large image blur with a small drive amount of the movable lens group for image stabilization. If the amount of movement of the movable lens group is large, the outer diameter of the movable lens group must be increased in order to eliminate light ray vignetting in the image stabilization state.
The weight of the movable lens group increases. In order to increase the so-called eccentricity sensitivity (the ratio Δx / ΔH of the image pre-correction amount Δx to the unit movement amount ΔH of the movable lens unit), the lens power of the fourth lens unit L4 itself must be increased. Therefore, the fourth lens unit L4 has a cemented lens and a positive lens for increasing the lens power.

In each of the embodiments, the first order from the object side
The lens unit L1 includes a meniscus-shaped negative lens having a convex surface directed toward the object side, a positive lens having a convex surface on both lens surfaces, and a positive lens having a convex surface directed toward the object side.

The second lens unit L2 is composed of a negative lens and a positive lens.

The third lens unit L3 is composed of a negative lens, a cemented lens of a negative lens having concave surfaces on both sides and a positive lens, and a negative lens.

The fifth lens unit L5 has two or more negative lenses and three or more positive lenses.

In each embodiment, the imaging magnification at the wide-angle end of the third lens unit L3 is β3w, the first lens unit and the second lens unit
The combined focal length at the wide-angle end of the lens group is f12W, the focal length of the entire lens system at the wide-angle end is fw, the focal length of the entire lens system at the telephoto end is ft, from the image-side surface vertex of the lens closest to the image side. When the distance to the shooting surface is Bf, 0.55 <| β3w | <1.5 (1)

[0040]

[Equation 3]

Bf / ft> 0.25 (3) One or more of the following conditions are satisfied.

Next, the technical meanings of the above conditional expressions will be described.

Conditional expression (1) defines the imaging magnification of the third lens unit L3. If the variable power (imaging magnification) of the third lens unit L3 becomes smaller than the lower limit value of the conditional expression (1), the divergent component of the light beam emitted from the third lens unit L3 weakens, so that the fourth lens unit L4 The height of the incident light flux from the optical axis can be suppressed small, the lens diameter of the fourth lens unit L4 can be reduced, and the lens weight can be reduced, which is advantageous for eccentric drive.
However, in order to gain a variable power ratio, it is necessary to increase the variable power of the other lens units. For example, if the lens power is increased (strengthen) to increase the variable power of the first lens unit L1, the first lens unit L1 Also, the canceling relation of the spherical aberration generated in the second lens unit L2 is not established. In addition, if the fourth lens unit L4 and the fifth lens unit L5 are used to secure zooming, various aberrations during image stabilization cannot be corrected. If the image forming magnification of the third lens unit L3 becomes larger than the upper limit value of the conditional expression (1), the variable magnification share of the third lens unit L3 becomes large, which is advantageous to secure a wide variable magnification range. The spherical aberration and the coma generated from the third lens unit L3 are deteriorated, and the lens diameter of the fourth lens unit L4 is also increased. Therefore, the lens weight of the fourth lens unit L4 is increased, which is also disadvantageous in decentering drive.

Conditional expression (2) defines the ratio of the focal length of the entire lens system at the wide-angle end and the telephoto end to the combined focal length of the first lens unit L1 and the second lens unit L2. If the lower limit of conditional expression (2) is exceeded, the first lens unit L1 and the second lens unit L1
When the combined focal length of the lens unit L2 becomes smaller, the height of the F number ray bundle can be made smaller due to the stronger positive refracting power, so that the outer diameter of the fourth lens unit L4, which is a vibration reduction unit, becomes smaller. The chromatic aberration or spherical aberration generated in the lens unit L1 and the second lens unit L2 becomes worse, and the negative power of the third lens unit L3 must be increased to correct it, and the power of the third lens unit L3 must be increased. It becomes difficult to correct the coma aberration caused by the increase. If the combined focal length of the first lens unit L1 and the second lens unit L2 becomes larger than the upper limit of conditional expression (2), correction of chromatic aberration and spherical aberration becomes easy, but the outer diameter of the third lens unit L3 becomes large. Is increased, and the lens weight is increased, which is disadvantageous for eccentric drive.

Conditional expression (3) represents the ratio of the distance from the image side apex of the lens closest to the image side to the photographing surface with respect to the focal length of the entire lens system at the telephoto end. If the value exceeds the lower limit, it becomes difficult to attach an attachment or the like between the lens body and the camera body.

In each embodiment, it is more preferable to set the numerical ranges of conditional expressions (1) to (3) as follows.

[0047] 0.6 <| β3w | <1.2 (1a)

[0048]

[Equation 4]

Bf / ft> 0.26 (3a) In each embodiment, with the above-described configuration, the angle of view 34 ° to 12 suitable for a photographic camera, a video camera, a video still camera, or the like. A zoom lens having an aperture ratio of about .degree. And an F number of about 2.8, and in particular, having an anti-vibration function, is capable of anti-vibration and has excellent aberration correction.

Next, an embodiment of a single lens reflex camera system using the zoom lens of the present invention will be described with reference to FIG. In FIG. 25, 10 is a single-lens reflex camera body, and 1
1 is an interchangeable lens equipped with a zoom lens according to the present invention,
Reference numeral 12 is a recording means such as a film or an image pickup element for recording a subject image obtained through the interchangeable lens 11, 13 is a finder optical system for observing the subject image from the interchangeable lens 11, and 14 is a recording means for the subject image from the interchangeable lens 11. 1
2 is a rotating quick return mirror for switching and transmitting to 2 and the finder optical system 13. When observing the subject image with the viewfinder, the quick return mirror 1
The subject image formed on the focusing plate 15 via the lens 4 is converted into an erect image by the pentaprism 16 and then magnified and observed by the eyepiece optical system 17. At the time of shooting, the quick return mirror 14 rotates in the direction of the arrow, and the subject image is formed and recorded on the recording means 12.

As described above, by applying the zoom lens of the present invention to an optical device such as a single-lens reflex camera interchangeable lens, an optical device having high optical performance can be realized.

The present invention can be similarly applied to an SLR (Single lens Reflex) camera without a quick return mirror.

Next, numerical examples of the present invention will be shown. In the numerical examples, i indicates the order of the surfaces from the object side, Ri is the radius of curvature of each surface, Di is the i-th and (i + 1) th optical member thickness or air gap, and Ni and vi are the i-th optical elements. It is the refractive index and Abbe number of the member for d-line. Table 1 shows the relationship between some of the above-mentioned conditional expressions and various numerical values in the numerical examples.

F is the focal length, FNo is the F number, and ω is the half angle of view.

[0055]

[Outer 1]

[0056]

[Outside 2]

[0057]

[Outside 3]

[0058]

[Outside 4]

[0059]

[Table 1]

[0060]

According to the present invention, even though the zoom lens has a large aperture, the diameter and weight of the vibration-proof lens group are both small, and a vibration-proof system is constructed, and good optical performance is obtained even in a vibration-proof state. In addition, it is possible to achieve a zoom lens having a vibration reduction function that is small in size as a whole and an optical device using the zoom lens.

[Brief description of drawings]

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

FIG. 2 is a lens cross-sectional view of a zoom lens at a telephoto end according to Numerical Example 1.

FIG. 3 is an aberration diagram when a wide-angle end of the zoom lens of Numerical Example 1 focuses on an object at infinity.

FIG. 4 is an aberration diagram when an object at infinity is focused at the telephoto end of the zoom lens according to Numerical Example 1.

5A and 5B are aberration diagrams when the zoom lens of Numerical Example 1 focuses at an object at infinity at the wide-angle end and at a standard angle of 0.5 °.

6A and 6B are aberration diagrams of the zoom lens of Numerical Example 1 at the telephoto end when focused on an object at infinity and when tilted at 0.5 °.

FIG. 7 is a lens cross-sectional view of a zoom lens at a wide-angle end according to Numerical Example 2.

FIG. 8 is a lens cross-sectional view of a zoom lens of a numerical example 2 at a telephoto end.

FIG. 9 is an aberration diagram when a wide-angle end of a zoom lens according to Numerical Example 2 focuses on an object at infinity.

FIG. 10 is an aberration diagram when an object at infinity is focused at the telephoto end of the zoom lens according to Numerical Example 2.

11A and 11B are aberration diagrams of the zoom lens of Numerical Example 2 at the wide-angle end when focused on an object at infinity and when tilted at 0.5 °.

FIG. 12 is a diagram showing aberrations of a zoom lens of Numerical Example 2 at the telephoto end when focused on an object at infinity and when tilted at 0.5 °.

FIG. 13 is a lens cross-sectional view at a wide-angle end of a zoom lens according to Numerical Example 3.

FIG. 14 is a lens cross-sectional view of a zoom lens at a telephoto end according to Numerical Example 3.

FIG. 15 is an aberration diagram of a zoom lens of Numerical Example 3 when focused on an object at infinity at the wide-angle end.

FIG. 16 is an aberration diagram when an object at infinity is focused at the telephoto end of the zoom lens of Numerical Example 3.

17A and 17B are aberration diagrams of the zoom lens of Numerical Example 3 at the wide-angle end when focused on an object at infinity and at a tilt of 0.5 °.

FIG. 18 is a diagram showing aberrations of a zoom lens of Numerical Example 3 at the telephoto end when focused on an object at infinity and when tilted at 0.5 °.

FIG. 19 is a lens cross-sectional view at a wide-angle end of a zoom lens according to Numerical Example 4.

FIG. 20 is a lens cross-sectional view of a zoom lens at a telephoto end according to Numerical Example 4.

FIG. 21 is an aberration diagram when a wide-angle end of the zoom lens of Numerical Example 4 focuses on an object at infinity.

FIG. 22 is an aberration diagram of a zoom lens of Numerical Example 4 when focused on an object at infinity at the telephoto end.

23A and 23B are aberration charts of a standard when an object at infinity is in focus and an aberration when tilted by 0.5 ° at the wide-angle end of the zoom lens of Numerical Example 4.

24A and 24B are aberration diagrams of the zoom lens of Numerical Example 4 at the telephoto end and at the time of focusing at an object at infinity and at a tilt of 0.5 °.

FIG. 25 is a schematic view of a main part of an optical device of the present invention

[Explanation of symbols]

L1 First lens unit L1 L2 Second lens group L2 L3 Third lens group L3 L4 Fourth lens group L4 L5 Fifth lens group L5 d d line g g line ΔM meridional image plane ΔS sagittal image plane SP aperture IP image plane

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Claims (11)

[Claims] 1. A first lens group having a positive refractive power, a second lens group, a third lens group having a negative refractive power, a fourth lens group having a positive refractive power, and a positive lens group having a positive refractive power in order from the object side. A fifth lens group, the distance between the first lens group and the second lens group at the telephoto end with respect to the wide-angle end changes, and the distance between the second lens group and the third lens group increases, In a zoom lens that performs zooming by moving the lens groups so that the distance between the third lens group and the fourth lens group changes, the fourth lens group is moved so as to have a component in a direction orthogonal to the optical axis. The zoom lens is characterized by displacing the image. 2. A first lens group having a positive refractive power, a second lens group having a positive or negative refractive power, a third lens group having a negative refractive power, and a fourth lens having a positive refractive power in order from the object side. Group, a fifth lens group having a positive refractive power, and a large distance between the first lens group and the second lens group at the telephoto end with respect to the wide-angle end, and the second lens group and the third lens group. Of the third lens group and the fourth lens group are small, and the distance between the fourth lens group and the fifth lens group is small, the second, third, and fourth lens groups are In a zoom lens that performs zooming by moving in the optical axis direction, the fourth lens group is moved so as to have a component in the direction perpendicular to the optical axis, and image blurring that occurs when the zoom lens vibrates is corrected. This is a zoom lens. 3. When the imaging magnification at the wide-angle end of the third lens group is β3w, the condition of 0.55 <| β3w | <1.5 is satisfied. Zoom lens. 4. The combined focal length of the first lens group and the second lens group at the wide-angle end is f12W, the focal length of the entire lens system at the wide-angle end is fw, and the focal length of the entire lens system at the telephoto end is ft. When, The zoom lens according to claim 1, 2 or 3, wherein the following condition is satisfied. 5. The zoom lens according to claim 1, wherein focusing is performed by moving the second lens group. 6. The zoom lens according to claim 1, wherein the first lens group is fixed with respect to the image plane for zooming. 7. The first lens group is fixed relative to the image plane for zooming.
The zoom lens according to any one of 6 above. 8. The zoom lens according to claim 1, wherein the fourth lens group includes, in order from the object side, a positive lens and a cemented lens including a positive lens and a negative lens. 9. When the distance from the image-side surface vertex of the most image-side lens to the shooting surface is Bf and the focal length ft of the entire lens system at the telephoto end is Bf / ft> 0.25. The zoom lens according to any one of claims 1 to 8, which is satisfied. 10. An optical system for forming an image on an image pickup device, according to claim 1.
Item zoom lens. 11. An optical apparatus comprising: the zoom lens according to claim 1; and an image pickup device that receives an image formed by the zoom lens.