JPH1138319A - Lens optical system having vibration proof function - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a lens optical system that can be used even inside an image formation optical system, by lightening vibration-proof aberration inside a correction optical system. SOLUTION: The correction optical system B is constituted by arraying a lens B1 having negative refracting power and a lens B2 having positive refracting power by an adjacent positional relation in order from an object side. Also, at least one surface of the lenses B1 and B2 is made into an aspherical surface. The respective surfaces of the lens B1 and the lens B2 are set as B11 , B12 , B21 and B22 in order from the object side. The center of curvature of the surface B12 is set as B1c , and that of the surface B12 is set as B2c , and the center of rotation at the time of turning the lens B1 is set as B1r , and that at the time of turning the lens B2 is set as B1r , and the center of rotation B1r exists between the surface B12 and the center of curvature B1c , and the center of rotation B2r exists between the surface B21 and the center of curvature B2c . Then, the lens B1 or B2 is rotated by centering the center of rotation B1r or B2r by corresponding to the deflection angle of a camera, so that the vibration of a photographing image is corrected.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention optically corrects a shake of a photographed image when an optical system vibrates or tilts by rotating one lens about one point on an optical axis. The present invention relates to a lens optical system having an image stabilizing function for stabilizing a captured image.

[0002]

2. Description of the Related Art When an image is taken from a moving object such as a running car or an airplane in flight, vibration is transmitted to a photographing system, and the photographed image is shaken. On the other hand, conventionally, various correction optical systems such as a photographic camera and a video camera having a function of preventing a shake of a captured image have been proposed.

For example, in Japanese Patent Application Laid-Open No. Sho 61-223819, in a photographing system in which a refraction type variable apex angle prism is arranged closest to the subject, the apex angle of the refraction type variable apex angle prism is adjusted according to the vibration of the imaging system. By changing, the image is deflected to stabilize the image.

Japanese Patent Application Laid-Open No. 2-239220 discloses a first lens unit having a negative refractive power and a second lens unit having a positive refractive power, each having an aspheric surface in order from the object side in front of the photographing system. An optical system is used to correct the shake of the captured image by rotating the second lens group.

Further, Japanese Patent Application Laid-Open No. 2-135408 discloses a zoom lens having positive, negative, positive, and positive refractive powers by moving a part of an imaging optical system in a direction perpendicular to an optical axis. In addition, correction of image shake at the time of shooting is performed.

JP-A-3-83006 discloses a zoom lens having a first positive lens unit, a second negative lens unit, and a third positive lens unit having a stop in order from the object side.
The image blur is corrected by rotating a part of the positive lens group.

[0007]

However, in the above-mentioned prior art, the correction optical system is arranged in front of the image forming optical system, and the movable lens group of the correction optical system is vibrated to eliminate the shake of the photographed image. When trying to obtain a still image, the diameter of the optical element used in the correction optical system is generally large, and there is a problem that the entire apparatus becomes large. For example, in the embodiment of Japanese Patent Application Laid-Open No. 2-239220, the diameter of the lens of the correction optical system is larger than the diameter of the lens used in the imaging system.

Therefore, in order to reduce the size of the entire optical system, it is desirable to have a correction optical system inside the imaging optical system. However, with such a lens configuration, image stabilization aberrations generated by performing image stabilization are more likely to appear than in the case where an image stabilization optical system is generally provided in front of the imaging optical system.

An object of the present invention is to solve the above-mentioned problems,
It is an object of the present invention to provide a lens optical system having an image stabilizing function that can improve image stabilization aberration in a correction optical system and can be used in an imaging optical system.

[0010]

According to the present invention, there is provided a lens optical system having an anti-vibration function, wherein a lens having a negative refractive power and a lens having a positive refractive power are positioned adjacent to each other. In an optical system having a relationship, at least one surface of the two lenses is aspherical, and one of the lens having the negative refractive power and the lens having the positive refractive power is rotated, and the other is rotated. By rotating the optical system around a fixed point on the optical axis between the surface facing the lens and the center of curvature of the surface, the shake of the captured image when the optical system is tilted is corrected. It is characterized by.

[0011]

DESCRIPTION OF THE PREFERRED EMBODIMENTS The present invention will be described in detail with reference to the illustrated embodiment. FIG. 1 is a schematic view of the basic configuration of an optical system. In order from the object side, a lens B ₁ having a negative refractive power and a lens B ₂ having a positive refractive power are arranged in an adjacent positional relationship. System B is configured. Also, lens B
_At least one surface of each of ₁ and B ₂ is an aspheric surface. B ₁₁ , B ₁₂ and B ₂₁ , B ₂₂ are respective surfaces of the lens B ₁ and the lens B _{2 in} order from the object side. B _1c is the center of curvature of the surface B ₁₂ , B _2c is the center of curvature of the surface B ₁₂ , and B _1r is the lens B ₁
B _2r is the center of rotation when rotating the lens B ₂ , the center of rotation B _1r exists between the surface B ₁₂ and the center of curvature B _1c , and the center of rotation B _2r present from the surface B ₂₁ between the center of curvature B _2c. The correction front A of the optical system front and lateral imaging optical system on the object side to the side A of B, transverse portion A ₂ of the imaging optical system A on the image side is disposed.

Of these, the lens B ₁ or B ₂ is rotated about the rotation center B _1r or B _2r in accordance with the camera shake angle, thereby correcting the shake of the photographed image.

As in the embodiment, when a part of the lens in the correction optical system B is rotated about a fixed point on the optical axis to correct the shake of the photographed image, the method of providing the aspherical surface and the rotation center are used. By properly determining the position, the correction optical system B
In this case, the image stabilization aberration generated during image stabilization can be considerably improved.

Therefore, how to give the aspherical surface and the center of rotation will be considered below. The relationship between the third order image stabilization aberration and the image stabilization aberration coefficient can be expressed as follows. ΔΥ (ε) = - (ε / 2) NA 2 (2+ cos2φ R) (IIε) -εNAY '[{2cos (φ R + φω)} (IIIε) + cosφ R · cos φω (Pε)] - (ε / 2) Y ′ ² {(2+ cos2φω) (Vε ₁ ) − (Vε ₂ )｝ (1) ΔΖ (ε) = − (ε / 2) NA ² sin2φ _R (IIε) −εNAY′tanω {sin (φ _R + φω)} (IIIε) + sinφ _R · cosφω (Pε)} − (ε / 2) Y ′ ² sin2φω (Vε ₁ ) (2)

Here, ε is the rotation angle of the lens group [rad] ΔΥ (ε) is the vertical image stabilization aberration ΔΖ (ε) is the horizontal image stabilization aberration NA is the numerical aperture Y ′ is the ideal image height φ _R is Petzval sum upon azimuthal φω is azimuth angle IIε the first-order coma aberration coefficient IIIε primary decentering astigmatism coefficient Pε formed between evaluation direction and Y-axis eccentricity of the ray on the object side principal plane Vipushiron ₁ Is the first-order eccentric distortion coefficient Vε ₂ is the first-order eccentric distortion additional aberration coefficient

In general, when a correction optical system is arranged in an image forming optical system, Vε ₁ and Vε ₂ are equal to the anti-vibration aberration coefficient II.
It is sufficiently small and negligible compared to ε and IIIε. Also, Pε
Cannot be changed irrespective of the aspherical surface or the position of the rotation center, and hence, only the anti-vibration aberration coefficients IIε and IIIε will be considered.

In particular, in order to facilitate understanding, a correction optical system B composed of B ₁ and B ₂ is modeled as follows using _two lenses. (1) The lenses B ₁ and B ₂ have the same curvature on the facing surfaces. (2) The lenses B ₁ and B ₂ have the same aspherical surface in the curved surface portion. (3) The lenses B ₁ and B ₂ are made of the same material. (4) There is no distance between the lenses B ₁ and B ₂ . (5) performing image stabilization by rotating the lens B _2.

At this time, the anti-vibration coefficients IIε and IIIε are expressed as follows, respectively. IIε = ｛Δ (h _cr ) + L _cr α ′ _cr } (ΣI _p + I _cf12 ) − ｛Δ (g _cr ) + L _cr α ′ _cr } (} II _p + II _cf12 ) + (h ′ _cr + L _cr α ′ _cr ) I _cr12 − (g ′ _cr + L _cr α ′ _cr ) II _cr12 + δ _cr ｛Δ (α _cr ) (ΣII _p + II _cf12 ) −Δ (α _cr ) (ΣII _p + II _cf12 ) + α ′ _cr I _cr12 −α ′ _cr II _cr12 ｝ −δ _cr b ((α _cr k ₁ −α _cr k ₂ )… (3) IIIε = ｛Δ (h _cr ) + L _cr α ′ _cr } (ΣII _p + II _cf12 ) − ｛Δ (g _cr ) + L _cr α ′ _cr } (ΣIII _p + III _cf12 ) + (h ′ _cr + L _cr α ′ _cr ) II _cr12 − (g ′ _cr + L _cr α ′ _cr ) III _cr12 + δ _cr ｛Δ (α _cr ) (ΣII _p + II _cf12 ) −Δ (α _cr ) (ΣIII _p + III _cf12 ) + α ′ _cr II _cr12 −α ′ _cr III _cr12 ｝ −δ _cr b (α _cr k ₂ −α _cr k ₃ )… (4)

[0019] However, b is a fourth order aspheric coefficient [delta] _c r is a distance L _c r from the surface B ₂₁ to the rotational center B _2r lens thickness of the lens B ₂ alpha _cr is the axial ray on the surface B _{21 cr} 'incidence angle alpha of the off-axis ray at the exit angle alpha _cr terms B ₂₂ of the axial ray in _cr is the surface B _22' incident angle alpha is the angle of emergence of the off-axis ray in the plane B ₂₂ Δ (α _cr) is alpha ' _cr -α _cr Δ (α _cr ) is α' _cr -α _cr g _cr is the incident height of an axial ray on the surface B ₂₁ g ' _cr is the exit height of the axial ray on the surface B ₂₂ h _cr is the surface B ₂₁ 'the _cr exit height of off-axis rays in the plane B ₂₂ Δ (g _cr) is g' incident height h of the axial ray in _cr -g _cr delta (h _cr) is h _'cr -h _cr .SIGMA.I _p anti-vibration spherical aberration coefficient of the lens group a ₁ on the object side than the lens ShigumaII _p coma aberration coefficient of the lens group a ₁ of the object side of the vibration reduction lens ShigumaIII _p non lens group a ₁ of the object side of the vibration-proof lens astigmatism coefficient I _CF12 fourth order aspheric coefficient b Coma aberration coefficient of the lens B ₁ in the case of the spherical aberration coefficient II _CF12 fourth order aspheric coefficient b = 0 of the lens B ₁ For 0 III _CF12 is a case of aspherical coefficients of fourth-order b = 0 Lens B ₁
Astigmatism coefficient I _cr12 fourth order aspheric coefficient b = spherical aberration coefficients of the lens B ₂ For 0 II _cr12 fourth order aspheric coefficient b = coma aberration coefficient of the lens B ₂ in the case of the 0 III of _cr12 is a lens B ₂ when the fourth order aspheric coefficient b = 0.
Astigmatism coefficient k ₁ is non-relative proportion k ₃ is the fourth-order aspheric coefficient of variation of the coma aberration coefficient for the ratio k ₂ is the fourth-order aspheric coefficient of variation of the spherical aberration coefficient for the fourth order aspheric coefficient Rate of change of astigmatism coefficient

Therefore, from the above equation, the anti-vibration aberration coefficient IIε,
The value of the fourth order aspherical coefficient b and the distance δ can be uniquely determined with respect to the target value of IIIε. Also, when performing the image stabilization by rotating the lens B _1, it is possible to obtain the fourth order of the values of aspherical coefficients b and the distance δ in substantially the same manner. However, since the lens B ₁ and B ₂ are actually in need of somewhat a distance to rotate, the value that can be actually improved image stabilization aberration to solutions obtained above are to have a certain area become.

Further, the rotation center B which can improve the image stabilization aberration
Position of _2r is present between the lens B ₂ faces B ₂₁ to pivot to its center of curvature B _2c. Conversely, when the rotation center B _2r is not provided in this area, coma aberration and image plane _tilt caused by performing image stabilization occur, and it becomes difficult to reduce the image stabilization aberration in the correction optical system B. .

Further, Tosa as the radius of curvature r of the lens B ₂ which rotates increases, the rotation angle of the lens B ₂ which rotates in order to correct image plane becomes large, and from the center of rotation B _2r also lens I'll go. At this time, the rotating lens B ₂
Since it is necessary to increase the diameter of the optical system, when the focal length at the telephoto end of the entire optical system is f, if the following expression (5) is not satisfied, the optical system cannot be practically used. | R | / | f | ≦ 15.5 (5)

In general, if the correction optical system is disposed closer to the object side than the imaging optical system, it is assumed that the lens in the correction optical system is rotated and used. A lens having a larger diameter than the lens is required, and the lens diameter in the correction optical system is inevitably considerably large. On the other hand, if the correction optical system is arranged in the image forming optical system, it is possible to avoid an increase in the lens diameter, and to reduce the size of the entire camera including the optical system.

However, when the correction optical system B is disposed in the image forming optical system A as in the embodiment as compared with the case where the correction optical system is disposed closer to the object side than the image forming optical system, image stabilization is performed. As a result, aberrations are likely to occur, and its improvement is difficult. In order to improve the image stabilization aberration, the original performance of the imaging optical system A may be impaired. Therefore, it is desirable to improve the image stabilization aberration in the correction optical system B.

In response to such a demand, the correction optical system B of this embodiment is very effective. However, lens B
_If the distance between ₁ and B ₂ is d and the radius of curvature of the surface of the rotating lens facing the other lens is r, if these do not satisfy the following equation (6), the correction optical system In B, aberrations typified by spherical aberration cannot be canceled each other, resulting in higher-order aberrations. | D | / | r | ≦ 0.12 (6)

The lens B ₁ constituting the correction optical system B
If the refracting power of the lens B ₂ is φ ₁ and the refracting power of the lens B ₂ is φ ₂ , if the following equation (7) is not satisfied, the correction optical system B itself causes considerable aberrations not limited to high-order aberrations. However, the original performance of the imaging optical system at rest cannot be guaranteed. −1.25 ≦ φ ₁ / φ ₂ ≦ −0.80… (7)

The focal length at the wide-angle end of the entire optical system is represented by f
_{When w} is given, the shape of the lens surfaces B ₁₁ and B ₂₂ is given by the following equation.
The above tendency is more likely to occur when the lens has a refractive power that does not satisfy (8). 4.1 ≦ | r ₁₁ | / | f _w | 4.1 ≦ | r ₂₂ | / | f _w | (8)

In particular, when the optical system is a variable magnification optical system, the same material can be used for the focal length anti-vibration lens at the telephoto end.
A correction optical system B that can easily avoid deterioration of the performance of the lens at rest can be configured. Conversely, when different materials are used, a correction optical system B that can easily avoid deterioration of the performance of the lens at rest can be configured. Becomes difficult.

The correction optical system B of this embodiment is composed of positive and negative lenses B ₁ and B ₂ having approximately the same refractive power. Even if the material of the correction optical system B is selected, the performance can be easily maintained. Further, since the plastic lens can be manufactured at a lower cost than the glass lens, the cost required for the correction optical system B can be suppressed.

FIG. 2 is a diagram showing the construction of the optical system according to the first embodiment. Both L1 and L3 have a positive refractive power, and are fixed at the time of zooming and focusing. Group
L3 has a correction optical system B. L2 is a second lens unit having a negative refractive power for zooming, L4 is a fourth lens unit for correcting the in-focus and fluctuating image plane, and the second lens unit L2 and the third lens during zooming. The group L3 moves from the wide-angle end to the telephoto end by moving in the direction of the arrow. In addition,
SP is a fixed stop.

The third lens unit L3 includes a lens unit L having a positive refractive power and a correcting optical system B having almost no refractive power. The correcting optical system B is a single lens having a negative refractive power in order from the object side. It is composed of a single lens B ₂ with B ₁ and positive refractive power. Then, the lens B ₂ around the rotation center B _2r on the optical axis lying between the center of curvature B _2C surface B ₁₂ and its surface, as shown in FIG. 1 is configured to rotate. Conversely, lens B
_{When 1} rotates, it is configured to rotate about a rotation center B _2r on the optical axis between the surface B ₁₂ and the curvature center B _1c of the surface. The lens B ₁ represents the surface B ₁₂ is an aspherical surface, lens B ₂ both surfaces is an aspherical surface.

At this time, depending on the camera shake, the lens B
By rotating ₂ , the positional deviation of the image plane is corrected while suppressing the aberration generated during image stabilization. In addition, since the correction optical system B has almost no refractive power, the performance at the time of standing still maintains the same performance as before the addition of the correction lens.

FIG. 3 is a diagram showing various aberrations of the first embodiment at the wide-angle end when focused on infinity, FIG. 4 is a diagram showing various aberrations at the telephoto end when focused on infinity, and FIG. upper lateral aberration diagram, FIG. 6 is axial lateral aberration view when correcting the deflection angle of 0.5 degrees lens B _2, the axis of the case 7 is obtained by correcting the deflection angle of 0.5 degrees lens B ₁ It shows an upper lateral aberration diagram. In addition,
In spherical aberration, a solid line represents a d line, a two-dot chain line represents a g line, a dotted line represents a sine condition, and a solid line represents a sagittal image plane and a dotted line represents a meridional image plane in astigmatism.

FIG. 8 is a block diagram of an optical system according to the second embodiment. The same elements as those shown in FIG. 2 are denoted by the same reference numerals. In the second embodiment, unlike the first embodiment, the order of the lenses constituting the correction optical system B is reversed, and the correction optical system B is a single lens B having a positive refractive power in order from the object side. It is constituted by a single lens B ₄ with ₃ and a negative refractive power. The lens B ₄ about the rotational center B _4r on the optical axis in the plane B ₄₁ of the lens B ₄ and between the center of curvature B _4c of the surface is configured to rotate. Conversely, when the lens B ₃ is rotated is configured to rotate about the rotation center B _3r on the optical axis, between the surface B ₃₂ and the center of curvature B _3c of the surface. The surface B of the lens B _3
32 is aspherical, lens B ₄ are both sides are aspherical. At this time, the position of the rotation center changes from the image plane side of the correction optical system to the object side. Therefore, even if it is necessary to change the rotation center position before or after the correction optical system B for some reason, the correction optical system B of this embodiment can easily cope with the need.

FIG. 9 is a diagram showing various aberrations of the second embodiment at the wide-angle end when focused on infinity, FIG. 10 is a diagram showing various aberrations at the telephoto end when focused on infinity, and FIG. upper lateral aberration diagram, FIG. 12 is a lens B ₄ at 0.5 degrees axial lateral aberration diagram when the corrected deflection angle of 13 axes when correcting the deflection angle of 0.5 degrees lens B ₃ It shows an upper lateral aberration diagram.

Next, concrete numerical examples of the first and second embodiments of the variable power optical system according to the present invention will be described.

In this numerical example, f is the overall focal length, Fno is the F number, and ω is the half angle of view. Δ is the distance from the surface of the correction optical system that faces the other of the rotating lens to the center of rotation, and Ri is the i-th lens in order from the object side.
The radius of curvature of the second lens surface, Di is the i-th lens thickness or air gap from the object side, and Ni and νi are the refractive index and Abbe number of the glass of the i-th lens in order from the object side.

Assuming that 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, R is the paraxial radius of curvature, and k, b, c, and d are the aspherical surface coefficients. And when
It is represented by the following equation.

X = (1 / R) H ² / [1+ {1- (1 + k) (H / R) ² } ^1/2 ] + bH ⁴ + cH ⁶ + dH ⁸ (9)

First Embodiment f = 1 to 12.28 Fno = 1.91 to 2.76 2ω = 58.2 ° to 5.2 ° Lens B ₁ : δ = 1.873 Lens B ₂ : δ = 1.936 R 1 = 8.415 D 1 = 0.24 N 1 = 1.846660 ν 1 = 23.8 R 2 = 4.584 D 2 = 0.99 N 2 = 1.603112 ν 2 = 60.6 R 3 = -105.742 D 3 = 0.05 R 4 = 4.219 D 4 = 0.59 N 3 = 1.712995 ν 3 = 53.8 R 5 = 11.354 D 5 = variable R 6 = 10.522 D 6 = 0.14 N 4 = 1.772499 v 4 = 49.6 R 7 = 1.088 D 7 = 0.53 R 8 = -2.961 D 8 = 0.14 N 5 = 1.696797 v 5 = 55.5 R 9 = 2.960 D 9 = 0.17 R10 = 2.512 D10 = 0.30 N 6 = 1.846660 ν 6 = 23.8 R11 = 11.778 D11 = Variable R12 = Aperture D12 = 0.25 R13 = 4.307 D13 = 0.80 N 7 = 1.583126 ν 7 = 59.4 R14 = -1.773 D14 = 0.14 N 8 = 1.824000 ν 8 = 37.2 R15 =-3.266 D15 = 0.11 R16 = -64.610 D16 = 0.23 N 9 = 1.530410 ν 9 = 55.5 R17 = 1.873 D17 = 0.14 R18 = 2.009 D18 = 0.76 N10 = 1.530410 ν10 = 55.5 R19 = -16.646 D19 = Variable R20 = 3.342 D20 = 0.14 N11 = 1.805181 ν11 = 25.4 R21 = 1.637 D21 = 0.75 N12 = 1.583126 ν12 = 59.4 R22 = -11.251 D22 = 0.68 R23 = ∞ D23 = 0.80 N13 = 1.516330 ν13 = 64.2 R24 = ∞ Focal length 1.00 3.38 12.28 D5 0.20 2.49 4.01 D11 4.09 1.80 0.27 D19 1.95 1.05 1.79 Aspheric coefficient R13 k = -4.28970 B = 4.42310 ・ 10 ^-4 C = -2.07446 ・ 10 ^-3 D = 1.65039 ・ 10 ^-3 R17 k = 0.00000 B = -2.00225 ・ 10 ^-3 C = -3.54799 ・ 10 ^-3 D = 0.00000 R18 k = 0.00000 B =- 1.18625 ・ 10 ^-4 C = -2.32790 ・ 10 ^-3 D = 0.00000 R19 k = 0.00000 B = 6.61803 ・ 10 ^-4 C = 6.29501 ・ 10 ^-4 D = 0.00000 R22 k = 2.995945 B = 1.07503 ・ 10 ^-3 C = 1.26569 ・ 10 ^-2 D ＝ -6.51939 ・ 10 ^-3

The second embodiment f = 1~12.36 Fno = 1.85~2.74 2ω = 58.8 ° ~5.2 ° Lens B _1: δ = 9.781 Lens _{B 2: δ = 9.780 R 1} = 8.513 D 1 = 0.24 N 1 = 1.846660 ν 1 = 23.8 R 2 = 4.638 D 2 = 1.00 N 2 = 1.603112 ν 2 = 60.6 R 3 = -1062.989 D 3 = 0.05 R 4 = 4.268 D 4 = 0.60 N 3 = 1.712995 ν 3 = 53.8 R 5 = 11.486 D 5 = Variable R 6 = 10.644 D 6 = 0.14 N 4 = 1.772499 ν 4 = 49.6 R 7 = 1.101 D 7 = 0.54 R 8 = -2.995 D 8 = 0.14 N 5 = 1.696797 ν 5 = 55.5 R 9 = 2.995 D 9 = 0.17 R10 = 2.542 D10 = 0.30 N 6 = 1.846660 ν 6 = 23.8 R11 = 11.915 D11 = Variable R12 = Aperture D12 = 0.25 R13 = 4.230 D13 = 0.80 N 7 = 1.583126 ν 7 = 59.4 R14 = -2.004 D14 = 0.14 N 8 = 1.824000 ν 8 = 37.2 R15 = -4.602 D15 = 0.11 R16 = 10.306 D16 = 0.49 N 9 = 1.530410 ν 9 = 55.5 R17 = -11.542 D17 = 0.11 R18 = -11.913 D18 = 0.39 N10 = 1.530410 ν10 = 55.5 R19 = 10.288 D19 = variable R20 = 2.859 D20 = 0.14 N11 = 1.805181 ν11 = 25.4 R21 = 1.772 D21 = 0.76 N12 = 1.58126 ν12 = 59 .4 R22 = -7.089 D22 = 0.69 R23 = ∞ D23 = 0.80 N13 = 1.516330 ν13 = 64.2 R24 = ∞ Focal length 1.00 3.58 12.36 D5 0.20 2.52 4.06 D11 4.14 1.82 0.28 D19 0.05 -0.88 -0.09 Aspheric coefficient R13 k = -2.73773 B = 1.27285 ・ 10 ^-3 C = 4.26883 ・ 10 ^-4 D = 4.28795 ・ 10 ^-4 R17 k = 0.00000 B = -1.91351 ・ 10 ^-5 C = 5.35427 ・ 10 ^-4 D = 0.00000 R18 k = 0.00000 B = -1.15145 / ^10-3 C = 7.25640 / ^10-5 D = 0.00000 R19 k = 0.00000 B = 0.00000 C = 0.00000 D = 0.00000 R22 k = 9.22143 B = 7.15761 / ^10-3 C = 6.94862 / ^10-3 D = -3.7042 ・ 10 ^-3

The radius of curvature inside the rotating lens B ₁ B ₂ B ₃ B ₄ 1.873 2.009 -11.542 -11.913 _.

The center of rotation distance 1.871 1.936 -9.781 -9.780 | r | / | f | 0.155 0.167 0.934 0.893 | d | / | r | 0.074 0.069 0.0095 0.0092 φ 1 / φ 2 -1.000 -1.000 -1.000 -1.000 | r | / | F _W | 64.61 16.646 10.306 10.28

[0044]

As described above, the lens optical system having the image stabilizing function according to the present invention can improve the aberration generated during image stabilization by the correction lens group without impairing the performance at rest. In addition, since a correction optical system can be configured inside the imaging optical system, downsizing can be achieved.

[Brief description of the drawings]

FIG. 1 is a schematic diagram of a basic configuration.

FIG. 2 is a lens cross-sectional view of the first embodiment.

FIG. 3 is a diagram illustrating various aberrations of the first embodiment at a wide-angle end in an infinity in-focus state.

FIG. 4 is a diagram illustrating various aberrations at the telephoto end in a focused state at infinity;

FIG. 5 is an axial lateral aberration diagram in an infinity in-focus condition at the telephoto end.

[6] In B ₂ in the infinity in-focus state in the telephoto end 0.
It is an axial transverse aberration figure at the time of correcting the deflection angle of 5 degrees.

FIG. 7 shows a lens B ₁ in an infinity in-focus condition at the telephoto end.
FIG. 7 is a view showing an on-axis lateral aberration when a shake angle of 0.5 degree is corrected by using FIG.

FIG. 8 is a sectional view of a lens according to a second embodiment.

FIG. 9 is a diagram illustrating various aberrations of the second embodiment at a wide-angle end in an infinity in-focus condition;

FIG. 10 is a diagram illustrating various aberrations at a telephoto end when focused on an object at infinity;

FIG. 11 is an axial lateral aberration diagram in an infinity in-focus condition at the telephoto end.

FIG. 12 shows a lens B in an infinity in-focus condition at the telephoto end.
₄ is a axial lateral aberration view when correcting the deflection angle of 0.5 degrees.

FIG. 13 shows a lens B in an infinity in-focus condition at the telephoto end.
FIG. 7 is a view showing an on-axis lateral aberration when a deflection angle of 0.5 degree is corrected in ₃ .

[Explanation of symbols]

I first lens group L2 second lens unit L3 third lens unit L4 fourth group A linear image optical system B correction optical system B _1, B _2, B _3, B ₄ lenses of the correction optical system

Claims (7)

[Claims] 1. An optical system having a lens having a negative refractive power and a lens having a positive refractive power in an adjacent positional relationship, wherein at least one surface of the two lenses is aspherical, and One of the lens having power and the lens having positive refracting power is rotated, and a fixed point on the optical axis between the surface facing the other lens and the center of curvature of the surface is centered. A lens optical system having an image stabilizing function, wherein the lens system is rotated to correct a shake of a captured image when the optical system is tilted. 2. The lens optical system according to claim 1, wherein a radius of curvature r of a surface of the rotating lens facing the other lens satisfies the following expression. | R | / | f | ≦ 15.5 where f is the focal length of the entire optical system, and when the optical system is a variable magnification optical system, is the focal length at the telephoto end. 3. A lens having a negative refractive power and a lens having a positive refractive power are arranged in an imaging system, and a lens having a negative refractive power and a lens having a positive refractive power are arranged between the lens having the negative refractive power and the lens having the positive refractive power. The lens optical system according to claim 1, wherein the distance d satisfies the following expression. | D | / | r | ≦ 0.12 where r is the radius of curvature of the surface of the rotating lens facing the other lens. 4. The protection according to claim 1, wherein the magnitude of the refractive power of the lens having the negative refractive power is substantially equal to that of the lens having the positive refractive power. Lens optical system with vibration function. 5. The lens having an anti-vibration function according to claim 4, wherein the surfaces of the lens having the negative refractive power and the lens having the positive refractive power that do not face each other have almost no refractive power. Optical system. 6. The anti-vibration function according to claim 1, wherein the lens having the negative refractive power and the lens having the positive refractive power are manufactured using the same material. Lens optics. 7. The lens optical system according to claim 6, wherein a material of the lens having the negative refractive power and a material of the lens having the positive refractive power are plastic.