JPH08136863A - Variable power optical system provided with vibration proofing function - Google Patents

Abstract

PURPOSE: To excellently compensate various kinds of eccentric aberrations and to miniaturize a whole device by appropriately arranging each lens element at the time of compensating the displacement of a photographic image. CONSTITUTION: This variable power optical system has at least two lens groups of a first group L1 of a positive refractive power and a second group L2 of a negative refractive power in order from the object side and varys the power from the wide-angle end to the telescopic end by changing an air gap between the first group L1 and the second group L2 and the second group L2 has a 21th group L21 of a negative refractive power and a 22th group L22 of a positive refractive power. At the time of varying the power from the wide-angle end to the telescopic end, the second group L2 is fixed and the first group L1 and a fifth group L5 are moved to the object side, respectively, as is shown by arrows. The compensation of the blur of a photographic screen (compensation of vibration) when the variable power optical system vibrates is performed by moving the 21th group L21 as an eccentric lens group in the direction orthogonal to the optical axis as shown by an arrow. In this case, the whole system is made to be the arrangement of positive, negative and positive refractive powers.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a variable power optical system having a function of correcting the blur of a photographed image due to the vibration of an optical system, that is, a so-called anti-vibration function. When moving in the direction to obtain the image stabilization effect, a sufficiently large image blur is corrected with a small amount of drive of the movable lens group, and at the same time, the optical performance is prevented from degrading when the image stabilization effect is exerted. The present invention relates to an optical system having a vibration function.

[0002]

2. Description of the Related Art When an image is taken from a moving object such as a car or an airplane in progress, vibration is transmitted to an image pickup system (photographing lens) and a photographed image is blurred.

Especially when using a photographing system having a long focal length, it is difficult to suppress the vibration of the photographing system. When the photographing system tilts due to vibration, the photographed image is displaced according to the tilt angle and the focal length of the photographing system. Therefore, in the still image capturing device, there is a problem that the capturing time must be sufficiently short in order to prevent deterioration of image quality.
Further, in the moving image capturing apparatus, it is difficult to maintain the composition setting. Therefore, in such photographing, it is necessary to perform correction so that displacement of the photographed image, so-called blurring of the photographed image does not occur even when the photographing system tilts due to vibration.

Conventionally, vibration-proof optical systems having a function of preventing the blurring of photographed images have been disclosed in, for example, Japanese Patent Application Laid-Open No. 50-80147, Japanese Patent Publication No. 56-21133, and Japanese Patent Application Laid-Open No. 61-2.
It is proposed in Japanese Patent No. 23819.

In Japanese Patent Application Laid-Open No. 50-80147, in a zoom lens having two afocal variable power systems, the angular magnification of the first variable power system is M ₁ and the angular power of the second variable power system is M.
_Then , the zooming is performed in each zooming system so as to have a relation of M ₁ = 1-1 / M ₂ when _2, and the _second zooming system is spatially fixed to correct the blurring of the image. We are trying to stabilize the image.

According to Japanese Patent Publication No. 56-21133, some optical members are moved in a direction of canceling the vibrational displacement of an image due to vibration in accordance with an output signal from a detecting means for detecting a vibrational state of an optical device. To stabilize the image.

In Japanese Patent Laid-Open No. 61-223819, in a photographing system in which a refracting variable apex angle prism is arranged closest to the subject, the apex angle of the refracting variable apex prism is changed according to the vibration of the photographing system. The image is deflected to stabilize the image.

In addition, Japanese Patent Publication No. 56-34847,
In Japanese Patent Publication No. 57-7414, an optical member that is spatially fixed against vibration is arranged in a part of the photographing system, and a photographed image is deflected by utilizing the prism action generated by the vibration of the optical member. A still image is obtained on the image plane.

Further, the vibration of the photographing system is detected by utilizing the acceleration sensor, and a part of the lens group of the photographing system is vibrated in the direction orthogonal to the optical axis in accordance with the signal obtained at this time to obtain a still image. There are also ways to get it.

[0010]

Generally, a mechanism for obtaining a still image by vibrating a part of lens groups of a photographing system to eliminate a blur of a photographed image is required for a large correction amount of the blur of the image and for the blur correction. It is desired that the amount of movement and the amount of rotation of the lens group (movable lens group) that vibrates in the vertical direction be small.

When a movable lens group is decentered, a large amount of eccentric coma, eccentric astigmatism, eccentric chromatic aberration, eccentric field curvature aberration, etc. occur when the image blur is corrected and the image is blurred. Come on. For example, when a large amount of eccentric distortion aberration occurs, the amount of movement of the image on the optical axis and the amount of movement of the image in the peripheral portion differ. For this reason, when the movable lens group is decentered in order to correct the image blur for the image on the optical axis, a phenomenon similar to the image blur occurs in the peripheral portion, which causes a significant deterioration in optical characteristics. come.

In this way, in the optical system having a vibration-proof function, the movable lens group is moved in the direction orthogonal to the optical axis, or at the same time, it is slightly rotated about one point on the optical axis as the center of rotation to make it eccentric. At this time, a small amount of eccentric aberration is generated in order to reduce the deterioration of image quality, and a large image blur can be corrected with a small amount of movement or a small amount of rotation of the movable lens group in order to reduce the size of the entire apparatus. It is required that the sensitivity (the ratio Δx / ΔH of the correction amount Δx of the image blur to the unit movement amount ΔH) is large.

As an optical system having a vibration isolation function, an optical system having an optical member that is spatially fixed against vibration is difficult to support the optical member and realizes a small optical system. Therefore, it was not suitable for the construction of a small and lightweight device. An optical system in which the variable apex angle prism is arranged on the most object side of the photographing system has an advantage that aberrations other than eccentric chromatic aberration hardly occur at the time of displacement correction, but it has a drawback that the driving member becomes large and the prism There is a drawback that it is difficult to simply correct the eccentric chromatic aberration that occurs. In an optical system that decenters a part of the lens group of the photographing system, the device can be downsized by appropriately selecting and arranging the lens group to be decentered, but various aberrations caused by decentering, that is, decentering coma There is a problem that it is difficult to realize a sufficiently large displacement correction with a sufficiently small driving amount while satisfactorily correcting the aberration, the eccentric astigmatism, the eccentric field curvature, and the like.

According to the present invention, when a part of the lens group of the variable power optical system is eccentrically driven in the direction perpendicular to the optical axis to correct the displacement (blur) of the photographed image, each lens element is properly arranged. Various eccentric aberrations are satisfactorily corrected by the above, and a sufficiently large displacement correction (vibration correction) is realized with a sufficiently small eccentric drive amount, thereby making it possible to reduce the size of the entire apparatus. For the purpose of providing.

[0015]

An optical system having an image stabilizing function according to the present invention comprises at least two lens groups, a first group having a positive refractive power and a second group having a negative refractive power, in order from the object side. A variable power optical system having variable power from the wide-angle end to the telephoto end by changing the air space between the first group and the second group, wherein the second group is the 21st group having negative refractive power. A second lens unit having a positive refractive power,
It is characterized in that the blur of the photographic screen caused when the variable power optical system vibrates is corrected by moving the group in the direction orthogonal to the optical axis.

[0016]

1 and 2 are lens cross-sectional views at the wide-angle end according to Numerical Embodiments 1 and 2 of the present invention. In Numerical Embodiment 1 of FIG. 1, L1 is the first group having a positive refractive power, and L2 is the second group having a negative refractive power.
L3 is a third group having a positive refractive power, L4 is a fourth group having a positive refractive power, and L5 is a fifth group having a negative refractive power. The second lens unit L2 includes a twenty-first lens unit having a negative refractive power and a twenty-second lens unit L22 having a positive refractive power. SP is an aperture and IP is an image plane.

During zooming from the wide-angle end to the telephoto end, the first lens unit L1 is fixed to the object side, the second lens unit is fixed, and the fifth lens unit is moved to the object side, as indicated by the arrow. The shake correction (vibration compensation) of the photographing screen when the variable-magnification optical system vibrates is performed by moving the 21st lens unit L21 as a decentering lens unit in the direction perpendicular to the optical axis as indicated by the arrow.

In this embodiment, the eccentricity sensitivity at the telephoto end is 3.09. The combined refractive power from the 22nd group to the 5th group is positive, which makes the whole system positive, negative,
It has a positive refractive power arrangement.

In Numerical Embodiment 2 of FIG. 2, L1 is the first group having a positive refractive power, L2 is the second group having a negative refractive power, L3 is the third group having a positive refractive power, and L4 is a negative refractive power. It is a fourth group of. The second group L2 has a negative refractive power 21st group L21 and a positive refractive power 22nd group L22. SP is an aperture and IP is an image plane.

Upon zooming from the wide-angle end to the telephoto end, the first lens unit L1 is moved to the object side, the second lens unit L2 is moved to the image side, and the third lens unit L3 and the fourth lens unit L4 are moved to the object side as indicated by arrows. I am letting you.
The shake correction (vibration compensation) of the photographing screen when the variable-magnification optical system vibrates is performed by moving the 21st lens unit L21 as a decentering lens unit in the direction perpendicular to the optical axis as indicated by the arrow.

In this embodiment, the eccentricity sensitivity at the telephoto end is 2.22. The combined refractive power from the 22nd lens unit to the 4th lens unit is positive, so that the entire system has positive, negative, and positive refractive power arrangements.

In Numerical Embodiments 1 and 2 of FIGS. 1 and 2, the first lens unit L1 is cemented with a meniscus negative lens whose convex surface faces the object side and a meniscus positive lens whose convex surface faces the object side. It consists of three lenses, a cemented lens and a positive lens. As a result, variation in aberration caused by zooming when the first group is moved to zoom is reduced, and good optical performance is obtained over the entire zoom range.

The twenty-first lens unit L21 as a decentering lens unit is composed of three lenses, a negative lens whose both lens surfaces are concave, and a cemented lens in which a negative lens and a positive lens are cemented. This reduces the amount of eccentric aberration such as eccentric chromatic aberration when correcting the blurring of the captured image that occurs when the variable-magnification optical system vibrates by moving the 21st lens unit L21 in the direction perpendicular to the optical axis. . In Numerical Embodiments 1 and 2, the focal lengths of the first lens group and the twenty-first lens group are f1, f21,
The focal lengths at the wide-angle end and the telephoto end of the entire system are fW and f, respectively.
When T

[0024]

[Equation 2] I try to satisfy the following conditions.

Conditional expression (1) defines the ratio between the focal length of the first lens unit having a positive refractive power and the focal length of the entire system at the wide-angle end and the telephoto end. When the lower limit of conditional expression (1) is exceeded and the focal length of the first lens unit becomes small, it becomes difficult to correct coma and astigmatism mainly at the telephoto end. On the other hand, if the value exceeds the upper limit, the amount of movement of the first lens unit for zooming must be increased, and the total lens length increases, which is not good.

Conditional expression (2) defines the ratio of the focal length of the second lens group having the negative refracting power having the decentering lens unit L21 to the focal length of the entire system at the wide-angle end and the telephoto end.
If the focal length of the second lens unit becomes smaller than the lower limit of conditional expression (2), it becomes difficult not only to correct various aberrations but also to increase the thickness of the lens and increase the weight of the lens, which is disadvantageous for eccentric drive. . On the other hand, if the upper limit is exceeded, on the other hand, the sensitivity to eccentricity decreases, and it becomes necessary to increase the eccentric drive amount. When the eccentric drive amount is large, it is necessary to increase the effective diameter of the eccentric lens group accordingly, which increases the lens weight, which is disadvantageous for the eccentric drive.

In the present invention, conditional expression (1) is given in consideration of superior aberration correction and superiority in eccentric drive during image stabilization.
(2) is preferably in the following range.

[0028]

(Equation 3) Further, it is preferable that the conditional expressions (1) and (2) are in the following ranges for a zoom lens of about 3 to 4 times that of the telephoto system.

[0029]

[Equation 4] Next, the optical characteristics of the variable power optical system having the image stabilizing function of the present invention will be described. Generally, if an attempt is made to correct image blur by decentering a part of lens groups of an optical system in parallel, decentration aberrations occur and the imaging performance deteriorates. Therefore, next, at the 23rd Applied Physics Lecture, from the standpoint of aberration theory, the occurrence of eccentric aberration when the movable lens group is moved in the direction orthogonal to the optical axis in an arbitrary refractive power arrangement to correct image blur I will explain based on the method presented by Matsui at the meeting (1962).

The aberration amount ΔY1 of the entire system when a part of the lens group P of the optical system is decentered in parallel by E is as shown in equation (a).
It is the sum of Y (E). Here, the aberration amount ΔY is represented by spherical aberration (I), coma aberration (II), astigmatism (III), Petzval sum (P), and distortion aberration (Y). Also decentering aberration Δ
Y (E) is the first-order decentering coma aberration (I
IE), first-order eccentric astigmatism (IIIE), first-order eccentric field curvature (PE), first-order eccentric distortion (VE1), first-order eccentric distortion-added aberration (VE2), and 1 It is represented by the next origin movement (ΔE).

From equation (d), equations (i) to (ΔE) to (V)
The incident angle alpha _P of the ray aberration up E2) is the lens group P in the optical system for parallel decentering lens group P, the aberration coefficients of the lens unit P when the _{αa P I P, II P,} III P, P
_P , V _P, and similarly, the aberration coefficients when the lens unit arranged on the image plane side of the lens unit P is one q-th lens unit as a whole, I _q , II _q , III _q , P _q , V _Represented using _q .

[0032]

(Equation 5) _{(VE1) = α 'P V} q - α P (V P + V q) - αa P' III q + αa P (III P + III q) = h P φ P V q - α P V P - (ha _{P φ P III q -αa P III} P) ‥‥‥ (h) (VE2) = αa P P q - αa P (P P + P q) = ha P φ P P q - αa P P P ‥‥‥ (i) In order to reduce the occurrence of eccentric aberration from the above formula, the aberration coefficients I _P , II _P , III _P , P _P , and V _P of the lens group P are set to small values, or the formula (a) is used. It is necessary to set the various aberration coefficients in a well-balanced manner so as to cancel each other as shown in the formula (i).

Next, the optical function of the variable power optical system having the image stabilizing function of the present invention is photographed by eccentrically driving some lens groups of the photographing optical system shown in FIG. 9 in the direction orthogonal to the optical axis. A model assuming an anti-vibration optical system for correcting image displacement will be described.

First, in order to realize a sufficiently large displacement correction with a sufficiently small eccentric drive amount, the primary origin movement (Δ
E) needs to be sufficiently large. Based on this, the condition for correcting the primary eccentric field curvature (PE) will be considered. FIG. 9 shows the photographic optical system in order from the object side.
It is composed of three lens groups of a group and a q-th group, of which the p-th group is moved in parallel in a direction orthogonal to the optical axis to correct the image blur.

Here, the refracting powers of the o-th group, the p-th group, and the q-th group are φ _o , φ _p , and φ _q , respectively, and the incident angles of the paraxial on-axis ray and the off-axis ray to each lens group are α , Αa, the incident heights of paraxial on-axis rays and off-axis rays to h, ha, and the same s
Notated with uffix. It is also assumed that each lens group is composed of a small number of lenses, and that each aberration coefficient shows a tendency of undercorrection.

Under these assumptions, focusing on the Petzval sum of each lens group, the Petzval sum P of each lens group
_o , P _p , and P _q are the refractive powers φ _o , φ _p , and φ _q of each lens group.
In proportion to, the following relationship is satisfied: P _o = Cφ _o ··· (j) P _p = Cφ _p ··· (k) P _q = Cφ _q (where C is a constant) ··· (l). Therefore, the primary eccentric field curvature (PE) that occurs when the p-th group is decentered in parallel can be rearranged as follows by substituting the above equation.

[0037] _{(PE) = Cφ p (h} p φ q -α p) ‥‥‥ (m) Therefore, in order to correct decentering field curvature a (PE) is phi _p =
It is necessary to set 0 or φ _q = α _p / h _p . However, if φ _p = 0, the primary origin movement (ΔE) becomes 0 and the displacement cannot be corrected. Therefore, a solution satisfying φ _q = α _p / h _p must be obtained. That is, since h _p > 0, at least α _p and φ _q need to have the same sign.

(A) When α _p > 0 φ _q > 0 to correct the eccentric field curvature, and inevitably φ _o >
It becomes 0. Further, if φ _p > 0 at this time, 0 <α _p <α
′ _P <1, the primary origin movement (ΔE) is as follows.

(ΔE) = − 2 (α _p ′ −α _p )> − 2 (n) That is, decentering sensitivity (ratio of displacement amount of blur of photographed image to unit displacement amount of eccentric lens group) Is smaller than 1. Further, as described above, the eccentricity sensitivity becomes 0 when φ _p = 0. Therefore, in such a case, φ _p <0 must be set.

(B) When α _p <0, φ _q <0, inevitably φ _o <0, and therefore inevitably φ _p > 0 due to the correction of the eccentric field curvature (PE).

From the above, the refractive power arrangement of the optical system which makes it possible to correct the primary eccentric field curvature (PE) while sufficiently increasing the primary origin movement (ΔE) is as follows. Is suitable.

[0042]

[Table 1] FIG. 10 (A) and FIG. 10 (B) respectively show a lens configuration having such a refractive power arrangement.

The present invention utilizes such a refractive power arrangement. Next, the features of the lens configuration of the present invention will be described. Generally, in an optical system, various aberrations are favorably corrected with a compact lens configuration by appropriately setting the refractive power of each lens group. Generally, when constructing an optical system in which some lens groups of an optical system are decentered parallel to the direction orthogonal to the optical axis to correct the displacement of a captured image, decentration sensitivity can be sufficiently increased. It is preferable to select a lens group to be decentered in parallel because it is relatively easy to correct decentration aberrations.

On the other hand, in order to make the apparatus itself compact, it is desirable to select a lens group having a relatively small lens outer shape as the lens group for decentering in parallel.

From the above viewpoint, the refractive power arrangement shown in FIG. 10A is adopted as an optical system for achieving the object of the present invention.

That is, at least two lens groups, that is, a first group having a positive refracting power and a second group having a negative refracting power, are provided in this order from the object side. A variable power optical system in which the distance between the two groups is changed, wherein the second group comprises, in order from the object side, a twenty-first group having a negative refractive power and a twenty-second group having a positive refractive power, By moving the 21st group in the direction perpendicular to the optical axis, the blurring of the photographed image due to the vibration is corrected.

Next, the optical action when the lens group having the refractive power arrangement shown in FIG. 10A is applied to the zoom lens including the long focal length in the telephoto system as in the present invention will be described.

The reason for assuming a telephoto zoom lens is that there is a situation in which the image stabilization function is more effective in the focal length region where image blurring tends to deteriorate the image quality.

Conventionally, as a zoom lens for a telephoto system, the refractive power arrangement of lens groups involved in zooming is positive in order from the object side,
There are four-group zoom lenses composed of lens groups having negative, positive, and positive refracting power, and three-group zoom lenses composed of lens groups having positive, negative, and positive refracting power. Moreover, while improving these and correcting various aberrations satisfactorily, a more compact lens structure was realized.
4-group zoom lens consisting of lens groups of positive and negative refractive power,
Further, there is a 5-group zoom lens including positive, negative, positive, positive, and negative refractive power lens groups.

The present invention is an improvement of the above zoom lens of the telephoto system in which the lens group having the second negative refracting power from the object side, which can realize a more compact lens structure, is arranged. Vibration compensation. When adding the vibration compensation mechanism to the lens group, it is necessary that the lens group to be driven is small and lightweight. Generally, in a telephoto zoom lens, the lens group disposed closest to the object side has a large outer diameter, and the outer diameter tends to gradually decrease toward the image plane side.

Therefore, it is conceivable to drive the lens unit having the negative refracting power disposed closest to the image plane side during image stabilization. However, if the lens group closest to the image surface is driven, it becomes necessary to increase the effective diameter of the lens group closer to the object than that.
It is not desirable due to the lens structure.

Therefore, in the present invention, the second lens group having a negative refracting power or a part of the lens group having a relatively small outer diameter is driven from the object side. When the entire lens group having the second negative refractive power from the object side is eccentrically driven, the decentering sensitivity is low with the conventional refractive power arrangement.
The eccentric drive amount required for displacement correction becomes large, which is not preferable in terms of the drive mechanism. Further, the larger the driving amount, the larger the occurrence of decentration aberration, which is disadvantageous in aberration correction.

On the contrary, if the negative refracting power of the second lens group is increased in order to increase the decentering sensitivity, the refracting power arrangement of the conventional zoom lens is destroyed, and the advantages of compactness and aberration correction are lost. .

Therefore, in the present invention, the second lens group having a negative refractive power from the object side is divided into two lens groups having a negative refractive power and a positive refractive power, and the lens group having a negative refractive power is decentered. As a group, it is of the eccentric drive type. In this case, the lens group on the object side of the decentering lens group has a positive refracting power, the decentering lens group has a negative refracting power, and the lens group on the image plane side of the decentering lens group has a positive refracting power. It corresponds to the configuration of (A).

This facilitates correction of eccentric image surface curvature. In addition, a lens unit having a negative refracting power has a negative refracting power of 2
By dividing the lens group into one lens group, the refractive power of the negative lens group serving as the decentering lens group becomes stronger than that of the original lens group having the negative refractive power. This increases the decentration sensitivity and suppresses the occurrence of decentration aberrations.

On the other hand, the lens group having a positive refracting power added by the division can maintain the refracting power arrangement as a conventional zoom lens, which is preferable for correction of aberration in the reference state before decentering. In addition, the two lens groups having the negative and positive refracting powers that have been divided are moved integrally during zooming or are fixed during zooming (the relative positions of the negative and positive lens groups in the optical axis direction are constant), so a new moving lens group is provided. This is advantageous in terms of configuration rather than adding.

As described above, according to the present invention, in the zoom lens in which the first group having the positive refractive power and the second group having the negative refractive power are arranged from the object side, the second group is negatively refracted in order from the object side. It is divided into a 21st lens group having a positive power and a 22nd lens group having a positive refractive power, and the 21st lens group is driven by parallel decentering to form a telescopic zoom lens having a compact lens structure We have realized a variable-magnification optical system with a vibration-proof function that keeps the diameter small and corrects the occurrence of aberrations due to decentering to a sufficiently small level.

When performing the vibration compensation, with the lens configuration as described above, it becomes possible to correct aberrations caused by decentering, especially decentered image surface curvature, and especially decentered image surface curvature and decentering coma aberration. Various aberrations can be corrected well, and a variable power optical system having an image stabilizing function is realized.

The variable-magnification optical diameter according to the present invention is a 5-group zoom lens of positive, negative, positive, positive and negative refracting powers or a positive, negative, positive and negative refracting powers in order from the object side. The present invention can be applied to various types of zoom lenses starting from a lens group having positive and negative refractive powers in addition to the four-group zoom lens of the lens group.

Next, numerical examples of the present invention will be shown. In the numerical examples, ri is the radius of curvature of the i-th lens surface in order from the object side, di is the i-th lens thickness and air gap from the object side, and ni and νi are the values of the i-th lens in order from the object side, respectively. The refractive index of glass and the Abbe number.

[0061]

[Outside 1]

[0062]

(Equation 6)

[0063]

[Outside 2]

[0064]

(Equation 7)

[0065]

As described above, according to the present invention, when a lens group of a part of the optical system is eccentrically driven in the direction perpendicular to the optical axis to correct the displacement (blurring) of a photographed image, each lens element By properly disposing various types of eccentric aberration, various eccentric aberrations can be satisfactorily corrected, and a sufficiently large displacement correction (vibration correction) can be realized with a sufficiently small eccentric drive amount, thus enabling miniaturization of the entire device. A variable power optical system having a function can be achieved.

[Brief description of drawings]

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

FIG. 2 is a lens cross-sectional view at a wide-angle end according to Numerical Example 2 of the present invention.

FIG. 3A is an aberration diagram of a normal state at a wide-angle end of Numerical Example 1 of the present invention. FIG. 3B is an aberration diagram of a vibration-proof state at a wide-angle end of Numerical Example 1 of the present invention when shaken once. C) Aberration diagram of the image stabilization state when -1 degree is shaken at the wide-angle end in Numerical Example 1 of the present invention.

4A is an aberration diagram in a normal state in the middle of Numerical Example 1 of the present invention. FIG. 4B is an aberration diagram in a vibration-proof state when shaken by 1 degree in the middle of Numerical Example 1 of the present invention. Aberration diagram of the image stabilization state when -1 degree in the middle of Numerical Example 1 of the present invention is shaken

5A is an aberration diagram in a normal state at a telephoto end according to Numerical Example 1 of the present invention. FIG. 5B is an aberration diagram in a vibration-proof state when the telephoto end according to Numerical Example 1 of the present invention is shaken once. C) Aberration diagram of the image stabilization state at the telephoto end of the numerical example 1 of the present invention when shaken by -1 degree.

6A is an aberration diagram in a normal state at the wide-angle end of Numerical Example 2 of the present invention, and FIG. 6B is an aberration diagram in a vibration-proof state at the wide-angle end of Numerical Example 2 of the present invention when shaken once. C) Aberration diagram of the image stabilization state when the wide-angle end is swung by -1 degree in Numerical Example 2 of the present invention.

FIG. 7A is an aberration diagram in a normal state in the middle of Numerical example 2 of the present invention. FIG. 7B is an aberration diagram in a vibration-proof state when shaken by 1 degree in the middle of Numerical example 2 of the present invention. Aberration diagram of the image stabilization state when shaken by -1 degree in the middle of Numerical Example 2 of the present invention

FIG. 8A is an aberration diagram of a normal state at a telephoto end of Numerical Example 3 of the present invention, and FIG. 8B is an aberration diagram of an image stabilization state when the telephoto end of Numerical Example 3 of the present invention is shaken once. C) Aberration diagram of the image stabilization state at the telephoto end of the numerical example 3 of the present invention when shaken by -1 degree.

FIG. 9 is a schematic diagram of a lens configuration for explaining decentering aberration correction in the present invention.

FIG. 10 is a schematic diagram of a lens configuration for explaining decentering aberration correction in the present invention.

[Explanation of Codes] L1 1st group L2 2nd group L3 3rd group L4 4th group L5 5th group L21 21st group L22 22nd group h Image height d d line g g line ΔM Meridional image surface ΔS Sagittal image surface

Claims (5)

[Claims] 1. At least two lens groups, a first group having a positive refractive power and a second group having a negative refractive power, are arranged in this order from the object side,
A variable power optical system that performs zooming from the wide-angle end to the telephoto end by changing the air space between the first group and the second group, wherein the second group has a negative refracting power of the 21st group and a positive refracting power. Having a 22nd group of forces, said second
A variable-magnification optical system having an anti-vibration function, which is characterized in that the first group is moved in a direction orthogonal to the optical axis to correct the blurring of a photographing screen that occurs when the variable-magnification optical system vibrates. 2. The first lens group has at least one positive lens and a negative lens, and the twenty-first lens group has at least one positive lens and a negative lens. A variable power optical system having the image stabilizing function of item 1. 3. When the focal lengths of the first group and the 21st group are f1 and f21, respectively, and the focal lengths at the wide-angle end and the telephoto end of the entire system are fW and fT, respectively: The variable power optical system having the image stabilizing function according to claim 2, wherein the following condition is satisfied. 4. A third group having a positive refracting power, a fourth group having a positive refracting power, and a fifth group having a negative refracting power in this order from the image plane side of the second group.
A group is provided, and when zooming from the wide-angle end to the telephoto end, the first
4. The variable power optical system having the image stabilizing function according to claim 1, wherein the group is moved to the object side and the fifth group is moved to the object side. 5. A third lens unit having a positive refractive power and a fourth lens unit having a negative refractive power are sequentially provided on the image plane side of the second lens unit, and the first lens unit is arranged at the time of zooming from the wide-angle end to the telephoto end. 4. The variable power optical system having the image stabilizing function according to claim 1, wherein the third group and the fourth group are moved to the object side, respectively.