JP2011112788A - Zoom lens, optical apparatus, and method for manufacturing zoom lens - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a zoom lens having a focusing lens and a vibration-proof lens arranged in the same lens group, and having small size and high image forming performance. <P>SOLUTION: The zoom lens comprises, in order from an object side, a first lens group G1 having positive refractive power, a second lens group G2 having negative refractive power, and a rear group Gr including an optical element Oc having positive refractive power. The zoom lens varies power from a wide angle end state to a telephoto end state by changing the intervals of the respective groups. The optical element Oc comprises, in order from the object side, a first segment group Gr1 having positive refractive power, a second segment group Gr2 having positive refractive power, a third segment group Gr3 having negative refractive power, and a fourth segment group Gr4 having positive refractive power, and focuses on a near-distance object point from an infinite-distance object point being conducted by moving the first segment group Gr1 along an optical axis, the third segment group Gr3 being moved to include a component in a direction perpendicular to the optical axis. <P>COPYRIGHT: (C)2011,JPO&INPIT

Description

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

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

JP 2006-221092 A

  However, in the conventional zoom lens, the focusing lens and the anti-vibration lens are located in different lens groups, and the focusing lens driving mechanism and the anti-vibration lens driving mechanism must be arranged separately, and the lens is small. There was a problem of being unsuitable for conversion.

  The present invention has been made in view of the above problems, and includes a zoom lens having a focusing lens and an anti-vibration lens arranged in the same lens group and having a small size and high imaging performance. An optical device and a zoom lens manufacturing method are provided.

  In order to solve the above problems, the present invention includes, in order from the object side, a first lens unit having a positive refractive power, a second lens group having a negative refractive power, and a rear group including an optical element having a positive refractive power. Then, by changing the distance between the groups, zooming from the wide-angle end state to the telephoto end state is performed, and the optical element includes, in order from the object side, a first subgroup of positive refractive power and a positive refractive power The second partial group, the third partial group having a negative refractive power, and the fourth partial group having a positive refractive power, and moving the first partial group along the optical axis from an object point at infinity. Provided is a zoom lens characterized by focusing on a short-distance object point and moving the third partial group so as to include a component in a direction orthogonal to the optical axis.

  The present invention also provides an optical device having the zoom lens.

  In addition, the present invention provides a zoom lens manufacturing method including, in order from the object side, a first lens group having a positive refractive power, a second lens group having a negative refractive power, and a rear group including an optical element having a positive refractive power. In this order, in order from the object side, the optical element includes a first partial group having positive refractive power, a second partial group having positive refractive power, a third partial group having negative refractive power, and a fourth partial group having positive refractive power. And changing the distance between the first lens group, the second lens group, and the rear group to change from the wide-angle end state to the telephoto end state, and using the first partial group as the optical axis. In order to focus from an infinite object point to a short-distance object point by moving along, and moving the third partial group so as to include a component in a direction orthogonal to the optical axis, in order from the object side, A zoom lens comprising: the first lens group, the second lens group, and the rear group. To provide a method of manufacturing.

  According to the present invention, a zoom lens having a focusing lens and an anti-vibration lens arranged in the same lens group and having a small size and high imaging performance, an optical device having the zoom lens, and a method for manufacturing the zoom lens are provided. can do.

1 is a diagram illustrating a lens configuration of a zoom lens according to a first example, where W indicates a wide-angle end state, M indicates an intermediate focal length state, and T indicates a telephoto end state. FIG. 4A is a diagram illustrating various aberrations of the zoom lens according to the first embodiment at an infinite focus state, and a lateral aberration diagram during image stabilization. FIG. 5A is a wide-angle end state, FIG. 5B is an intermediate focal length state, and FIG. Each aberration diagram in the telephoto end state is shown. FIG. 5A is a diagram illustrating various aberrations of the zoom lens according to the first example when the close-up shooting distance is in focus, and a lateral aberration diagram at the time of image stabilization, in which (a) is Rw = 1000 mm, (b) is Rm = 1000 mm, (c) Each aberration diagram at Rt = 1000 mm is shown. FIG. 6 is a diagram illustrating a lens configuration of a zoom lens according to Example 2, where W indicates a wide-angle end state, M indicates an intermediate focal length state, and T indicates a telephoto end state. FIG. 7A is a diagram illustrating various aberrations of the zoom lens according to the second embodiment at an infinite focus state and a lateral aberration diagram at the time of image stabilization. FIG. 10A is a wide-angle end state, FIG. Each aberration diagram in the telephoto end state is shown. FIG. 7A is a diagram illustrating various aberrations of the zoom lens according to the second exemplary embodiment when a close-up shooting distance is in focus, and a lateral aberration diagram when image stabilization is performed. FIG. 9A illustrates Rw = 1000 mm, FIG. 9B illustrates Rm = 1000 mm, and FIG. Each aberration diagram at Rt = 1000 mm is shown. FIG. 10 is a diagram illustrating a lens configuration of a zoom lens according to Example 3, where W indicates a wide-angle end state, M indicates an intermediate focal length state, and T indicates a telephoto end state. FIG. 7A is a diagram illustrating various aberrations of the zoom lens according to the third exemplary embodiment in an infinite focus state and a lateral aberration diagram during image stabilization. FIG. 10A is a wide-angle end state, FIG. 9B is an intermediate focal length state, and FIG. Each aberration diagram in the telephoto end state is shown. FIG. 9A is a diagram illustrating various aberrations of the zoom lens according to the third example when the close-up shooting distance is in focus, and a lateral aberration diagram when the image stabilization is performed, where FIG. 9A is Rw = 1000 mm, FIG. Each aberration diagram at Rt = 1000 mm is shown. FIG. 10 is a diagram illustrating a lens configuration of a zoom lens according to a fourth example, where W indicates a wide-angle end state, M indicates an intermediate focal length state, and T indicates a telephoto end state. FIG. 9A is a diagram illustrating various aberrations of the zoom lens according to the fourth exemplary embodiment when the zoom lens is in focus, and a lateral aberration diagram when the image stabilization is performed, in which FIG. 9A is a wide-angle end state, FIG. Each aberration diagram in the telephoto end state is shown. FIG. 9A is a diagram illustrating various aberrations of the zoom lens according to the fourth example when the close-up shooting distance is in focus, and a lateral aberration diagram when the image stabilization is performed, in which Ra = 1000 mm, (b) Rm = 1000 mm, and (c). Each aberration diagram at Rt = 1000 mm is shown. FIG. 10 is a diagram illustrating a lens configuration of a zoom lens according to Example 5, where W indicates a wide-angle end state, M indicates an intermediate focal length state, and T indicates a telephoto end state. FIG. 9A is a diagram illustrating various aberrations of the zoom lens according to Example 5 in an infinite focus state and a lateral aberration diagram at the time of image stabilization. FIG. 10A is a wide-angle end state, FIG. Each aberration diagram in the telephoto end state is shown. FIG. 10 is a diagram illustrating various aberrations of the zoom lens according to Example 5 in a close focus state and a lateral aberration diagram during image stabilization, in which (a) shows Rw = 1000 mm, (b) shows Rm = 1000 mm, and (c) shows. Each aberration diagram at Rt = 1000 mm is shown. 1 shows an electronic still camera equipped with a zoom lens according to an embodiment, where (a) shows a front view and (b) shows a rear view. Sectional drawing along the AA line of Fig.16 (a) is shown. The manufacturing method of the zoom lens of this application is shown.

  Hereinafter, a zoom lens according to an embodiment of the present application will be described with reference to the drawings. The following embodiments are only for facilitating the understanding of the invention, and excluding additions and substitutions that can be performed by those skilled in the art without departing from the technical idea of the present invention. It is not intended.

  The zoom lens according to the present embodiment includes, in order from the object side, a first lens group having a positive refractive power, a second lens group having a negative refractive power, and a rear group including an optical element having a positive refractive power, By changing the interval between the groups, zooming from the wide-angle end state to the telephoto end state is performed, and the optical element includes, in order from the object side, a first subgroup having positive refractive power and a first partial group having positive refractive power. A second partial group, a third partial group having a negative refractive power, and a fourth partial group having a positive refractive power, and moving the first partial group along the optical axis to move from the object point at infinity. Focusing on an object point is performed, and the third partial group is moved so as to include a component in a direction orthogonal to the optical axis.

  With such a configuration, it is possible to achieve a compact zoom lens having a high imaging performance by disposing the focusing lens and the anti-vibration lens in the same lens group.

  Here, since the first partial group of positive refractive power in the optical element has less fluctuations in various aberrations during focusing, the first partial group is moved closer to the object point at infinity by moving along the optical axis. It is configured to focus on a distance object point. In addition, the third partial group of negative refractive power in the optical element has a small outer diameter of the lens and is suitable for disposing an anti-vibration driving mechanism on the outer periphery of the lens. By moving so as to include the components in the orthogonal direction, the image plane such as camera shake is corrected, that is, the image stabilization is performed.

  In the zoom lens, it is desirable that the distance in the optical axis direction between the second part group and the third part group and the distance in the optical axis direction between the third part group and the fourth part group are always fixed. With this configuration, when the present optical element is applied to a lens unit having a positive refractive power in a variable power optical system, the moving mechanism of the lens unit can be simplified, and decentration aberrations can be generated during zooming. Can be suppressed.

  In the zoom lens, it is preferable that the second partial group includes at least three positive lenses and at least one negative lens. With this configuration, the second partial group can satisfactorily correct various aberrations of the entire optical element, and can reduce aberration fluctuations during focusing and during image stabilization.

  Since the second partial group has the first partial group that is the focusing group on the object side and the third partial group that is the image stabilizing group on the image side, respectively, correction of aberration fluctuations during focusing and during image stabilization is possible. In order to perform well, a positive lens component for correcting aberration fluctuation at the time of focusing is arranged on the object side in the second partial group, and a positive lens component for correcting aberration fluctuation at the time of image stabilization on the image side in the second partial group. Are arranged so that different lens components correct aberration variations during focusing and during image stabilization. Here, the object side positive lens component for correcting aberration fluctuation at the time of focusing has at least two positive lenses and at least one negative lens, and the image side positive lens component for correcting aberration fluctuation at the time of image stabilization. By having a configuration including at least one positive lens, it is possible to satisfactorily correct aberration fluctuations during focusing and during image stabilization. The lens component refers to a lens made up of a single lens or a cemented lens.

In addition, it is desirable that the zoom lens satisfies the following conditional expression (1).
(1) 0.60 <Fb1 / Fb234 <1.70
Here, Fb1 represents the focal length of the first partial group, and Fb234 represents the combined focal length of the second partial group, the third partial group, and the fourth partial group.

  Conditional expression (1) is a conditional expression that defines an appropriate range of the ratio of the combined focal length of the second partial group, the third partial group, and the fourth partial group and the focal length of the first partial group. By satisfying conditional expression (1), it is possible to reduce aberration variation during focusing while reducing the overall length of the optical element.

  When exceeding the upper limit of conditional expression (1), the space | interval of a 1st partial group and a 2nd partial group spreads, and the full length of an optical element enlarges. If the refractive power of the second partial group is decreased in order to narrow this interval, the image plane fluctuation during image stabilization increases.

  Note that by setting the upper limit value of conditional expression (1) to 1.50, it is possible to more favorably correct the image plane fluctuation during image stabilization.

  If the lower limit value of conditional expression (1) is not reached, the distance between the first partial group and the second partial group is narrowed, making it difficult to secure a focusing space. If the refractive power of the second subgroup is increased to widen this interval in order to secure the space for focusing, the variation in spherical aberration at the time of focusing increases.

  By setting the lower limit value of conditional expression (1) to 0.80, it is possible to further reduce the variation of spherical aberration during focusing.

In addition, it is desirable that the zoom lens satisfies the following conditional expression (2).
(2) 0.60 <(Fb1 + Fb234) × Fb0 / (Fb1 × Fb234) <1.40
However, Fb1 is the focal length of the first partial group, Fb234 is the combined focal length of the second partial group, the third partial group, and the fourth partial group, and Fb0 is the focal point of the optical element when focused at infinity. Each distance is shown.

  By satisfying conditional expression (2), it is possible to reduce aberration fluctuations during focusing while reducing the overall length of the optical element.

  When exceeding the upper limit of conditional expression (2), the space | interval of a 1st partial group and a 2nd partial group spreads, and the full length of an optical element enlarges. If the refractive power of the second partial group is decreased in order to narrow this interval, the image plane fluctuation during image stabilization increases.

  Note that by setting the upper limit value of conditional expression (2) to 1.20, it is possible to more favorably correct image plane fluctuations during image stabilization.

  When the lower limit value of conditional expression (2) is not reached, the distance between the first partial group and the second partial group is narrowed, making it difficult to secure a focusing space. If the refractive power of the second subgroup is increased to widen this interval in order to secure the space for focusing, the variation in spherical aberration at the time of focusing increases.

  Note that by setting the lower limit value of conditional expression (2) to 0.80, it is possible to further reduce the fluctuation of spherical aberration during focusing.

In addition, it is desirable that the zoom lens satisfies the following conditional expression (3).
(3) | Fall / Ff | <1.30
Here, Fall is the focal length of the zoom lens at the time of focusing on infinity, and Ff is composed of the most image side lens of the first partial group and all the lenses arranged on the object side from the image side lens. The combined focal length when the optical system is focused at infinity is shown.

  Conditional expression (3) is a composite focal length at the time of focusing at infinity of an optical system composed of the most image side lens of the first partial group and all the lenses arranged on the object side from the image side lens. And an appropriate range of the ratio of the focal lengths of the zoom lens at the time of focusing on infinity. By satisfying conditional expression (3), various aberrations such as spherical aberration can be corrected satisfactorily.

  The definition of the above range means that the most object of the second partial group with respect to an optical system composed of the most image side lens of the first partial group and all the lenses arranged on the object side of the image side lens. This is equivalent to prescribing the magnification of an optical system composed of the lens on the side and all the lenses arranged on the image side with respect to the lens on the object side. When the conditional expression (3) is satisfied, the magnifications of the first partial group and the second partial group are made equal, or the magnification of the first partial group is made smaller than the magnification of the second partial group. As a result, the aberration of the optical system constituted by the most image side lens of the first partial group and all the lenses arranged on the object side from the image side lens is made equal to the aberration of the second partial group. Alternatively, the effect of making the aberration smaller than that of the second subgroup is obtained, and various aberrations of the zoom lens are corrected favorably.

  When the upper limit of conditional expression (3) is exceeded, it becomes difficult to correct various aberrations such as spherical aberration.

  By setting the upper limit value of conditional expression (3) to 1.00, various aberrations such as spherical aberration can be corrected more favorably.

  In the zoom lens, it is desirable that the rear group is composed of only the optical element. With such a configuration, the configuration of the optical system can be simplified.

  In the zoom lens, it is preferable that the rear group is composed of two lens groups, and the lens group on the image side of the two lens groups is composed of the optical element. With such a configuration, if the object side lens unit is a lens unit with negative refractive power, the image plane fluctuation during zooming can be reduced, and if the object side lens unit is a lens unit with positive refractive power, the aperture is An optical system having a large ratio can be realized.

  In the zoom lens, it is desirable to dispose an aperture stop at a position adjacent to the object side or the image side of the first partial group. With such a configuration, the aperture stop driving mechanism, the focusing lens driving mechanism, and the anti-vibration lens driving mechanism can be arranged in one optical element, and the zoom lens can be reduced in size.

  In addition, it is preferable that the zoom lens has a distance from the apex of the lens surface closest to the image side to the image surface (back focus) and is about 10 mm to 30 mm.

  The zoom lens preferably has an image height of 5.0 mm to 12.5 mm, and more preferably 5.0 mm to 9.5 mm.

  Hereinafter, numerical examples of the zoom lens according to the present embodiment will be described with reference to the accompanying drawings.

(First embodiment)
FIG. 1 is a diagram illustrating a lens configuration of a zoom lens according to a first example, where W indicates a wide-angle end state, M indicates an intermediate focal length state, and T indicates a telephoto end state. In addition, the code | symbol which shows the lens used for the following description is described only in the telephoto end state T, and description is abbreviate | omitted about another state. The same applies to other embodiments.

  The zoom lens according to Example 1 includes, in order from the object side, a first lens group G1 having a positive refractive power, a second lens group G2 having a negative refractive power, an aperture stop S1, and an optical element Oc having a positive refractive power. A rear group Gr, a dust-proof glass G, an optical low-pass filter OLPF, and a cover glass CG of a solid-state imaging device arranged on the image plane I.

  The first lens group G1 is composed of, in order from the object side, a biconvex positive lens L11, a negative meniscus lens L12 having a convex surface facing the object side, and a positive meniscus lens L13 having a convex surface facing the object side. It consists of a lens.

  The second lens group G2 is composed of a negative meniscus lens L21 having a convex surface facing the object side, a biconcave negative lens L22, and a positive meniscus lens L23 having a convex surface facing the object side. The lens includes a negative meniscus lens L24 having a convex surface directed toward the image plane I side.

  The optical element Oc (rear group Gr) includes, in order from the object side, a first partial group Gr1 having a positive refractive power, a second partial group Gr2 having a positive refractive power, a third partial group Gr3 having a negative refractive power, and a field stop. S2 and a fourth partial group Gr4 having positive refracting power, and by moving the first partial group Gr1 along the optical axis, focusing from an infinite object point to a short-distance object point is performed. Image shift is performed on the image plane I by moving the subgroup Gr3 so as to include a component in a direction orthogonal to the optical axis.

  The first partial group Gr1 includes a biconvex positive lens Lr1.

  The second partial group Gr2 includes, in order from the object side, a cemented lens formed by cementing a biconvex positive lens Lr2 and a negative meniscus lens Lr3 having a convex surface facing the image plane I, and a biconvex positive lens Lr4. The lens is composed of a cemented lens formed by cementing a negative meniscus lens Lr5 having a convex surface toward the object side and a biconvex positive lens Lr6.

  The third partial group Gr3 includes, in order from the object side, a cemented lens formed by cementing a biconvex positive lens Lr7 and a biconcave negative lens Lr8.

  The fourth partial group Gr4 includes, in order from the object side, a biconvex positive lens Lr9 and a negative meniscus lens Lr10 having a convex surface directed toward the image plane I side.

  In the zoom lens according to Example 1, when zooming from the wide-angle end state W to the telephoto end state T, the first lens group G1 moves to the object side, and the second lens group G2 has a concave shape on the object side. The optical element Oc (rear group Gr) moves to the object side along the locus along the optical axis.

  Further, the diagonal image height IH from the center of the solid-state imaging device of the first embodiment to the diagonal is 8.5 mm.

  Table 1 below shows specification values of the zoom lens of the first example. In the table, (overall specifications) indicates the focal length F in each state of the wide-angle end state (W), the intermediate focal length state (M), and the telephoto end state (T), and the F number FNO.

  In (surface data), the object surface is the object surface, the surface number is the lens surface number counted from the object side, r is the radius of curvature of the lens surface, d is the surface spacing of the lens surfaces, nd is the d-line (wavelength λ = 587.6 nm), νd is the Abbe number with respect to the d-line (wavelength λ = 587.6 nm), (variable) is the variable surface interval in focus, (stop) is the aperture stop S1, and (field stop) is the field of view. The diaphragm S2 and the image plane represent the image plane I, respectively. Note that “∞” of the radius of curvature r indicates a plane, and the refractive index of air nd = 1.00000 is omitted.

  In addition, (variable interval at the time of focusing) includes the wide-angle end state (W), the intermediate focal length state (M), and the telephoto end state (T) at the time of focusing at infinity and focusing on the close range. The value of the variable interval at the focal length f and magnification β is shown. D0 represents the distance from the object to the lens surface closest to the object, Bf represents the back focus, and TL represents the total length of the zoom lens. The (anti-vibration lens group movement amount and image plane movement amount at the time of anti-shake correction) includes a wide-angle end state (W), an intermediate focal length state (M) at the time of focusing on infinity and focusing on a close range, The image plane movement amount with respect to the lens movement amount in each state of the telephoto end state (T) is shown. Further, (value corresponding to the conditional expression) indicates a value corresponding to each conditional expression.

  In all the following specification values, “mm” is generally used as the focal length f, radius of curvature r, surface interval d and other lengths, etc. unless otherwise specified, but the optical system is proportional. Even if it is enlarged or proportionally reduced, the same optical performance can be obtained. Further, the unit is not limited to “mm”, and other appropriate units may be used. In all of the following embodiments, the same reference numerals as in this embodiment are used and the description thereof is omitted.

(Table 1)
(Overall specifications)
(W) (M) (T)
F 30.00 60.00 107.00
FNO 4.3 4.8 5.8

(Surface data)
Surface number rd nd νd
Object ∞
1) 104.9987 2.5000 1.516800 19.16
2) -98.0161 0.1000
3) 28.5522 1.1000 1.784700 50.44
4) 19.4068 4.4000 1.497820 14.95
5) 389.5870 (variable)
6) 223.4423 1.0000 1.741000 23.59
7) 22.0105 1.1000
8) -51.8131 1.0000 1.741000 23.59
9) 11.7594 2.2000 1.846660 56.14
10) 122.2362 1.2000
11) -16.7910 1.0000 1.741000 23.59
12) -1136.5791 (variable)
13> (Aperture) ∞ (Variable)
14) 73.3665 2.0000 1.516800 19.16
15) -27.2390 (variable)
16) 29.6447 3.3000 1.497820 14.95
17) -14.4744 1.0000 1.801000 36.97
18) -61.3016 0.1000
19) 13.3150 2.9000 1.517420 23.98
20) -157.6315 1.9000
21) 390.7053 1.0000 1.846660 56.14
22) 27.4326 2.0000 1.487490 17.31
23) -78.1115 2.7773
24) 106.3359 2.0000 1.805180 52.30
25) -15.0924 0.4904 1.804400 32.25
26) 15.0529 1.4000
27) (Field stop) ∞ 1.4924
28) 22.1990 2.1000 1.647690 38.54
29) -26.2091 1.1000
30) -9.6432 1.0000 1.795000 27.82
31) -22.0307 (variable)
32) ∞ 0.5000 1.516800 19.16
33) ∞ 4.6000
34) ∞ 1.8700 1.516800 19.16
35) ∞ 0.3000
36) ∞ 0.7000 1.516800 19.16
37) ∞ Bf
Image plane ∞

(Variable interval during focusing)
Focusing at infinity Focusing at close range
(W) (M) (T) (W) (M) (T)
F, β 30.00000 60.00000 107.00000 -0.03156 -0.06044 -0.10444
D0 ∞ ∞ ∞ 916.7700 906.4179 897.9680
d 5 1.81805 12.56575 16.54552 1.81805 12.56575 16.54552
d12 10.60697 5.94020 1.07619 10.60697 5.94020 1.07619
d13 1.40000 1.40000 1.40000 1.79703 2.53373 3.47996
d15 3.61101 3.61101 3.61101 3.21398 2.47728 1.53105
d31 15.16379 19.43504 28.76907 15.16379 19.43504 28.76907
Bf 0.50000 0.50000 0.50000 0.50000 0.50000 0.50000
TL 83.22999 93.58214 102.03195 83.22998 93.58216 102.03194

(Moving amount of image stabilization lens and amount of image plane movement during image stabilization)
Focusing at infinity Focusing at close range
(W) (M) (T) (W) (M) (T)
F, β 30.00000 60.00000 107.00000 -0.03156 -0.06044 -0.10444
Lens ± 0.122 ± 0.211 ± 0.292 ± 0.122 ± 0.211 ± 0.292
Image plane ± 0.157 ± 0.314 ± 0.560 ± 0.157 ± 0.314 ± 0.560

(Lens group data)
Group Start surface Focal length
G1 1 +45.606
G2 6 -10.732
Gr 14 +15.896

(Values for conditional expressions)
(1) Fb1 / Fb234 = 1.143
(2) (Fb1 + Fb234) × Fb0 / (Fb1 × Fb234) = 0.903
(3) | Fall / Ff | = 0.741

  2A and 2B are graphs showing various aberrations of the zoom lens according to the first embodiment in the infinitely focused state and lateral aberrations during image stabilization. FIG. 2A is a wide-angle end state, and FIG. 2B is an intermediate focal length state. (C) shows aberration diagrams in the telephoto end state. FIGS. 3A and 3B are graphs showing various aberrations of the zoom lens according to the first example when the close-up shooting distance is in focus and lateral aberrations during image stabilization. FIG. 3A shows Rw = 1000 mm, and FIG. 3B shows Rm = 1000 mm. (C) shows each aberration diagram of Rt = 1000 mm.

  In each aberration diagram, FNO is the F number, Y is the image height, NA is the numerical aperture, d is the d-line (λ = 587.6 nm), g is the g-line (λ = 435.6 nm), C Indicates the c-line (λ = 656.3 nm), and F indicates the f-line (λ = 486.1 nm). In the aberration diagram showing astigmatism, the solid line indicates the sagittal image plane, and the broken line indicates the meridional image plane. An aberration diagram showing lateral chromatic aberration is shown with reference to the d-line. In the aberration diagrams of all the following examples, the same reference numerals as those in this example are used, and description thereof is omitted.

  From each aberration diagram, the zoom lens according to the first example has excellent imaging performance with various aberrations corrected well from the wide-angle end state to the telephoto end state and during the image stabilization correction in each state. I understand that.

(Second embodiment)
FIG. 4 is a diagram illustrating the lens configuration of the zoom lens according to Example 2. W represents a wide-angle end state, M represents an intermediate focal length state, and T represents a telephoto end state.

  The zoom lens according to Example 2 includes, in order from the object side, a first lens group G1 having a positive refractive power, a second lens group G2 having a negative refractive power, an aperture stop S1, and an optical element Oc having a positive refractive power. A rear group Gr, a dust-proof glass G, an optical low-pass filter OLPF, and a cover glass CG of a solid-state imaging device arranged on the image plane I.

  The first lens group G1 is composed of, in order from the object side, a biconvex positive lens L11, a negative meniscus lens L12 having a convex surface facing the object side, and a positive meniscus lens L13 having a convex surface facing the object side. It consists of a lens.

  The second lens group G2 includes, in order from the object side, a cemented lens formed by cementing a biconcave negative lens L21, a biconcave negative lens L22, and a positive meniscus lens L23 having a convex surface toward the object side, and an image. It is composed of a negative meniscus lens L24 having a convex surface facing the surface I side.

  The optical element Oc (rear group Gr) includes, in order from the object side, a first partial group Gr1 having a positive refractive power, a second partial group Gr2 having a positive refractive power, a third partial group Gr3 having a negative refractive power, and a field stop. S2 and a fourth partial group Gr4 having positive refracting power, and by moving the first partial group Gr1 along the optical axis, focusing from an infinite object point to a short-distance object point is performed. Image shift is performed on the image plane I by moving the subgroup Gr3 so as to include a component in a direction orthogonal to the optical axis.

  The first partial group Gr1 includes a biconvex positive lens Lr1.

  The second partial group Gr2 includes, in order from the object side, a cemented lens formed by cementing a biconvex positive lens Lr2 and a negative meniscus lens Lr3 having a convex surface facing the image plane I, and a biconvex positive lens Lr4. And a cemented lens formed by cementing a biconcave negative lens Lr5 and a biconvex positive lens Lr6.

  The third partial group Gr3 includes, in order from the object side, a cemented lens formed by cementing a biconvex positive lens Lr7 and a biconcave negative lens Lr8.

  The fourth partial group Gr4 includes, in order from the object side, a biconvex positive lens Lr9 and a negative meniscus lens Lr10 having a convex surface directed toward the image plane I side.

  In the zoom lens according to the second example, when zooming from the wide-angle end state W to the telephoto end state T, the first lens group G1 moves to the object side, and the second lens group G2 has a concave shape on the object side. The optical element Oc (rear group Gr) moves to the object side along the locus along the optical axis.

  Further, the diagonal image height IH from the center of the solid-state imaging device of the second embodiment to the diagonal is 8.5 mm.

  Table 2 below shows specification values of the zoom lens of the second embodiment.

(Table 2)
(Overall specifications)
(W) (M) (T)
F 30.00 60.00 107.00
FNO 4.3 4.8 5.8

(Surface data)
Surface number rd nd νd
Object ∞
1) 107.0898 2.5000 1.518230 58.89
2) -99.2726 0.1000
3) 28.8641 1.1000 1.784700 26.30
4) 19.4065 4.4000 1.497820 82.56
5) 623.6707 (variable)
6) -101.6830 1.0000 1.741000 52.67
7) 24.6928 1.1000
8) -64.6171 1.0000 1.741000 52.67
9) 11.7906 2.2000 1.846660 23.78
10) 114.2322 1.2000
11) -18.8537 1.0000 1.741000 52.67
12) -731.1191 (variable)
13> (Aperture) ∞ (Variable)
14) 56.9161 1.8000 1.516800 64.12
15) -26.1469 (variable)
16) 31.5479 3.6000 1.497820 82.56
17) -15.1490 1.1000 1.801000 34.96
18) -67.0657 0.1000
19) 13.3178 3.2000 1.517420 52.32
20) -143.8096 2.1000
21) -114.9972 1.1000 1.846660 23.78
22) 34.8934 2.2000 1.487490 70.45
23) -54.4846 2.8255
24) 106.3359 2.0000 1.805180 25.43
25) -15.0924 0.5000 1.804400 39.57
26) 15.0522 1.4000
27) (Field stop) ∞ 1.7841
28) 20.5121 2.1000 1.647690 33.79
29) -30.0605 1.1000
30) -10.0058 1.0000 1.795000 45.30
31) -21.5527 (variable)
32) ∞ 0.5000 1.516800 64.12
33) ∞ 4.6000
34) ∞ 1.8700 1.516800 64.12
35) ∞ 0.3000
36) ∞ 0.7000 1.516800 64.12
37) ∞ Bf
Image plane ∞

(Variable interval during focusing)
Focusing at infinity Focusing at close range
(W) (M) (T) (W) (M) (T)
F, β 30.00000 60.00000 107.00000 -0.03154 -0.06033 -0.10411
D0 ∞ ∞ ∞ 916.5652 906.2131 897.7633
d 5 2.22767 12.97537 16.95514 2.22767 12.97537 16.95514
d12 10.44476 5.77799 0.91398 10.44476 5.77799 0.91398
d13 1.45757 1.45757 1.45757 1.84273 2.55124 3.44966
d15 3.39604 3.39604 3.39604 3.01088 2.30237 1.40395
d31 13.92910 18.20035 27.53438 13.92910 18.20035 27.53438
Bf 0.50000 0.50000 0.50000 0.50000 0.50000 0.50000
TL 83.43475 93.78691 102.23670 83.43476 93.78690 102.23670

(Moving amount of image stabilization lens and amount of image plane movement during image stabilization)
Focusing at infinity Focusing at close range
(W) (M) (T) (W) (M) (T)
F, β 30.00000 60.00000 107.00000 -0.03154 -0.06033 -0.10411
Lens ± 0.128 ± 0.221 ± 0.303 ± 0.128 ± 0.221 ± 0.303
Image plane ± 0.157 ± 0.314 ± 0.560 ± 0.157 ± 0.314 ± 0.560

(Lens group data)
Group Start surface Focal length
G1 1 +45.606
G2 6 -10.732
Gr 14 +16.308

(Values for conditional expressions)
(1) Fb1 / Fb234 = 0.909
(2) (Fb1 + Fb234) × Fb0 / (Fb1 × Fb234) = 0.891
(3) | Fall / Ff | = 0.558

  FIGS. 5A and 5B are graphs showing various aberrations of the zoom lens of Example 2 in the infinite focus state and lateral aberrations during image stabilization. FIG. 5A is a wide-angle end state, and FIG. 5B is an intermediate focal length state. (C) shows aberration diagrams in the telephoto end state. 6A and 6B are graphs showing various aberrations of the zoom lens according to the second example in the close-up shooting distance state and lateral aberrations at the time of image stabilization. FIG. 6A shows Rw = 1000 mm, FIG. 6B shows Rm = 1000 mm, (C) shows each aberration diagram of Rt = 1000 mm.

  From each aberration diagram, the zoom lens according to the second example has excellent imaging performance because various aberrations are well corrected from the wide-angle end state to the telephoto end state and during the image stabilization correction in each state. I understand that.

(Third embodiment)
FIG. 7 is a diagram illustrating the lens configuration of the zoom lens according to Example 3, where W indicates a wide-angle end state, M indicates an intermediate focal length state, and T indicates a telephoto end state.

  The zoom lens according to Example 3 includes, in order from the object side, a first lens group G1 having a positive refractive power, a second lens group G2 having a negative refractive power, an aperture stop S1, and an optical element Oc having a positive refractive power. A rear group Gr, a dust-proof glass G, an optical low-pass filter OLPF, and a cover glass CG of a solid-state imaging device arranged on the image plane I.

  The first lens group G1 is composed of, in order from the object side, a biconvex positive lens L11, a negative meniscus lens L12 having a convex surface facing the object side, and a positive meniscus lens L13 having a convex surface facing the object side. It consists of a lens.

  The second lens group G2 includes, in order from the object side, a cemented lens formed by cementing a biconcave negative lens L21, a biconcave negative lens L22, and a positive meniscus lens L23 having a convex surface toward the object side. It is composed of a concave negative lens L24.

  The optical element Oc (rear group Gr) includes, in order from the object side, a first partial group Gr1 having a positive refractive power, a second partial group Gr2 having a positive refractive power, a third partial group Gr3 having a negative refractive power, and a field stop. S2 and a fourth partial group Gr4 having positive refracting power, and by moving the first partial group Gr1 along the optical axis, focusing from an infinite object point to a short-distance object point is performed. Image shift is performed on the image plane I by moving the subgroup Gr3 so as to include a component in a direction orthogonal to the optical axis.

  The first partial group Gr1 includes a biconvex positive lens Lr1.

  The second partial group Gr2 includes, in order from the object side, a cemented lens formed by cementing a biconvex positive lens Lr2 and a negative meniscus lens Lr3 having a convex surface facing the image plane I, and a biconvex positive lens Lr4. And a cemented lens formed by cementing a biconcave negative lens Lr5 and a biconvex positive lens Lr6.

  The third partial group Gr3 includes, in order from the object side, a cemented lens formed by cementing a biconvex positive lens Lr7 and a biconcave negative lens Lr8.

  The fourth partial group Gr4 includes, in order from the object side, a biconvex positive lens Lr9 and a negative meniscus lens Lr10 having a convex surface directed toward the image plane I side.

  In the zoom lens according to the third example, when zooming from the wide-angle end state W to the telephoto end state T, the first lens group G1 moves to the object side, and the second lens group G2 has a concave shape on the object side. The optical element Oc (rear group Gr) moves to the object side along the locus along the optical axis.

  Further, the diagonal image height IH from the center of the solid-state imaging device of the third embodiment to the diagonal is 8.5 mm.

  Table 3 below shows specification values of the zoom lens of the third example.

(Table 3)
(Overall specifications)
(W) (M) (T)
F 30.00 60.00 107.00
FNO 4.3 4.8 5.8

(Surface data)
Surface number rd nd νd
Object ∞
1) 125.1574 2.5000 1.518230 58.89
2) -84.3301 0.1000
3) 28.3895 1.1000 1.784700 26.30
4) 18.9466 4.4000 1.497820 82.56
5) 419.5247 (variable)
6) -223.8932 0.8000 1.741000 52.67
7) 27.9983 1.1000
8) -41.3655 0.8000 1.741000 52.67
9) 12.3312 2.0000 1.846660 23.78
10) 160.7640 1.2000
11) -21.0724 0.8000 1.741000 52.67
12) 459.4400 (variable)
13> (Aperture) ∞ (Variable)
14) 122.4843 2.0000 1.516800 64.12
15) -28.4773 (variable)
16) 27.1989 2.8000 1.497820 82.56
17) -15.5490 0.8000 1.801000 34.96
18) -56.2214 0.1000
19) 12.4713 2.4000 1.517420 52.32
20) -468.0896 1.7000
21) -438.8420 0.8000 1.846660 23.78
22) 28.7077 1.6000 1.487490 70.45
23) -69.4120 2.6225
24) 112.2112 2.0000 1.805180 25.43
25) -15.9263 0.5000 1.804400 39.57
26) 15.8839 1.4000
27) (Field stop) ∞ 2.3924
28) 24.2073 2.1000 1.647690 33.79
29) -21.1678 1.1000
30) -9.8464 1.0000 1.795000 45.30
31) -27.4317 (variable)
32) ∞ 0.5000 1.516800 64.12
33) ∞ 4.6000
34) ∞ 1.8700 1.516800 64.12
35) ∞ 0.3000
36) ∞ 0.7000 1.516800 64.12
37) ∞ Bf
Image plane ∞

(Variable interval during focusing)
Focusing at infinity Focusing at close range
(W) (M) (T) (W) (M) (T)
F, β 30.00000 60.00000 107.00000 -0.03150 -0.06051 -0.10449
D0 ∞ ∞ ∞ 917.2587 907.7213 900.3241
d 5 2.29727 12.34224 16.45053 2.29727 12.34224 16.45053
d12 11.85041 6.39808 0.86562 11.85041 6.39808 0.86562
d13 0.42422 0.42422 0.42422 0.91515 1.76585 2.95151
d15 4.54719 4.54719 4.54719 4.05626 3.20556 2.01990
d31 15.03736 19.98210 28.80352 15.03736 19.98210 28.80352
Bf 0.49996 0.49996 0.49996 0.49996 0.49996 0.49996
TL 82.74133 92.27869 99.67587 82.74134 92.27868 99.67588

(Moving amount of image stabilization lens and amount of image plane movement during image stabilization)
Focusing at infinity Focusing at close range
(W) (M) (T) (W) (M) (T)
F, β 30.00000 60.00000 107.00000 -0.03154 -0.06033 -0.10411
Lens ± 0.125 ± 0.213 ± 0.300 ± 0.125 ± 0.213 ± 0.300
Image plane ± 0.157 ± 0.314 ± 0.560 ± 0.157 ± 0.314 ± 0.560

(Lens group data)
Group Start surface Focal length
G1 1 +45.606
G2 6 -11.422
Gr 14 +17.209

(Values for conditional expressions)
(1) Fb1 / Fb234 = 1.433
(2) (Fb1 + Fb234) × Fb0 / (Fb1 × Fb234) = 0.904
(3) | Fall / Ff | = 0.849

  FIGS. 8A and 8B are graphs showing various aberrations of the zoom lens according to the third example in the infinite focus state and lateral aberrations when the image stabilization is performed. FIG. 8A is a wide-angle end state, and FIG. (C) shows aberration diagrams in the telephoto end state. FIGS. 9A and 9B are graphs showing various aberrations of the zoom lens according to the third example when the close-up shooting distance is in focus and lateral aberrations during image stabilization. FIG. 9A shows Rw = 1000 mm, and FIG. 9B shows Rm = 1000 mm. (C) shows each aberration diagram of Rt = 1000 mm.

  From each aberration diagram, the zoom lens according to the third example has excellent imaging performance because various aberrations are well corrected from the wide-angle end state to the telephoto end state and during image stabilization correction in each state. I understand that.

(Fourth embodiment)
FIG. 10 is a diagram illustrating a lens configuration of a zoom lens according to Example 4, where W indicates a wide-angle end state, M indicates an intermediate focal length state, and T indicates a telephoto end state.

  The zoom lens according to Example 4 includes, in order from the object side, a first lens group G1 having a positive refractive power, a second lens group G2 having a negative refractive power, and a rear group Gr including an optical element Oc having a positive refractive power. , A dust-proof glass G, an optical low-pass filter OLPF, and a cover glass CG of a solid-state imaging device disposed on the image plane I.

  The first lens group G1 is composed of, in order from the object side, a biconvex positive lens L11, a negative meniscus lens L12 having a convex surface facing the object side, and a positive meniscus lens L13 having a convex surface facing the object side. It consists of a lens.

  The second lens group G2 is composed of a biconcave negative lens L21.

  The rear group Gr includes, in order from the object side, a third lens group G3 having negative refractive power, an aperture stop S1, and an optical element Oc having positive refractive power.

  The third lens group G3 of the rear group Gr includes, in order from the object side, a cemented lens formed by cementing a biconcave negative lens Lr1 and a biconvex positive lens Lr2, and a negative lens with a convex surface facing the image plane I side. It comprises a meniscus lens Lr3.

  The optical element Oc of the rear group Gr includes, in order from the object side, a first partial group Gr1 having a positive refractive power, a second partial group Gr2 having a positive refractive power, a third partial group Gr3 having a negative refractive power, and a field stop S2. And a fourth partial group Gr4 having positive refractive power, and the first partial group Gr1 is moved along the optical axis to focus from an infinite object point to a short-distance object point. Image shift is performed on the image plane I by moving the group Gr3 so as to include a component in a direction orthogonal to the optical axis.

  The first partial group Gr1 of the optical element Oc is composed of a biconvex positive lens Lr4.

  The second partial group Gr2 of the optical element Oc includes, in order from the object side, a cemented lens formed by cementing a biconvex positive lens Lr5 and a negative meniscus lens Lr6 having a convex surface toward the image plane I, and a biconvex shape. The lens includes a positive lens Lr7, and a cemented lens formed by cementing a biconcave negative lens Lr8 and a biconvex positive lens Lr9.

  The third partial group Gr3 of the optical element Oc includes, in order from the object side, a cemented lens formed by cementing a biconvex positive lens Lr10 and a biconcave negative lens Lr11.

  The fourth partial group Gr4 of the optical element Oc includes, in order from the object side, a biconvex positive lens Lr12 and a negative meniscus lens Lr13 having a convex surface directed toward the image plane I side.

  In the zoom lens according to Example 4, when zooming from the wide-angle end state W to the telephoto end state T, the first lens group G1 moves to the object side, and the second lens group G2 has an S-shaped locus. The third lens group G3 moves along the optical axis along a concave locus on the object side, and the optical element Oc moves toward the object side.

  Further, the diagonal image height IH from the center of the solid-state imaging device of the fourth embodiment to the diagonal is 8.5 mm.

  Table 4 below shows specification values of the zoom lens of the fourth example.

(Table 4)
(Overall specifications)
(W) (M) (T)
F 30.00 60.00 107.00
FNO 4.3 4.8 5.8

(Surface data)
Surface number rd nd νd
Object ∞
1) 80.5887 2.5000 1.518230 58.89
2) -125.6437 0.1000
3) 30.1350 1.1000 1.784700 26.30
4) 20.1659 4.4000 1.497820 82.56
5) 774.6747 (variable)
6) -139.0822 1.0000 1.741000 52.67
7) 23.4929 (variable)
8) -37.1938 1.0000 1.741000 52.67
9) 13.3906 2.2000 1.846660 23.78
10) -5477.8456 1.2000
11) -19.5048 1.0000 1.741000 52.67
12) -523.1128 (variable)
13> (Aperture) ∞ (Variable)
14) 64.7705 1.9000 1.516800 64.12
15) -26.6175 (variable)
16) 29.3621 3.4650 1.497820 82.56
17) -15.1957 1.1000 1.801000 34.96
18) -62.0277 0.1000
19) 13.2921 3.0000 1.517420 52.32
20) -105.3128 2.0000
21) -155.6218 1.1000 1.846660 23.78
22) 30.9418 2.1000 1.487490 70.45
23) -75.8545 2.5029
24) 106.3359 2.0000 1.805180 25.43
25) -15.0924 0.5000 1.804400 39.57
26) 15.0522 1.4000
27) (Field stop) ∞ 2.0046
28) 21.2520 2.1000 1.647690 33.79
29) -26.3195 1.1000
30) -10.1531 1.0000 1.795000 45.30
31) -24.9104 (variable)
32) ∞ 0.5000 1.516800 64.12
33) ∞ 4.6000
34) ∞ 1.8700 1.516800 64.12
35) ∞ 0.3000
36) ∞ 0.7000 1.516800 64.12
37) ∞ Bf
Image plane ∞

(Variable interval during focusing)
Focusing at infinity Focusing at close range
(W) (M) (T) (W) (M) (T)
F, β 30.00000 60.00000 107.00000 -0.03156 -0.06030 -0.10430
D0 ∞ ∞ ∞ 916.3279 904.9658 897.5260
d 5 2.18046 12.93514 16.90794 2.18046 12.93514 16.90794
d 7 1.36173 2.36263 1.36173 1.36173 2.36263 1.36173
d12 10.22924 5.55622 0.69846 10.22924 5.55622 0.69846
d13 1.42558 1.42558 1.42558 1.81567 2.53378 3.45546
d15 3.85828 3.85828 3.85828 3.46819 2.75008 1.82840
d31 14.27431 18.55389 27.87955 14.27431 18.55389 27.87955
Bf 0.50000 0.50000 0.50000 0.50000 0.50000 0.50000
TL 83.67210 95.03424 102.47403 83.67210 95.03424 102.47405

(Moving amount of image stabilization lens and amount of image plane movement during image stabilization)
Focusing at infinity Focusing at close range
(W) (M) (T) (W) (M) (T)
F, β 30.00000 60.00000 107.00000 -0.03154 -0.06033 -0.10411
Lens ± 0.124 ± 0.215 ± 0.296 ± 0.124 ± 0.215 ± 0.296
Image plane ± 0.157 ± 0.314 ± 0.560 ± 0.157 ± 0.314 ± 0.560

(Lens group data)
Group Start surface Focal length
G1 1 +45.606
G2 6 -27.052
G3 8 -20.092
Gr 14 +16.308

(Values for conditional expressions)
(1) Fb1 / Fb234 = 1.015
(2) (Fb1 + Fb234) × Fb0 / (Fb1 × Fb234) = 0.894
(3) | Fall / Ff | = 0.643

  FIGS. 11A and 11B are graphs showing various aberrations of the zoom lens according to the fourth example in the infinitely focused state and lateral aberrations at the time of image stabilization. FIG. 11A is a wide-angle end state, and FIG. 11B is an intermediate focal length state. (C) shows aberration diagrams in the telephoto end state. 12A and 12B are graphs showing various aberrations of the zoom lens according to the fourth example when the close-up shooting distance is in focus and lateral aberrations during image stabilization. FIG. 12A shows Rw = 1000 mm, and FIG. 12B shows Rm = 1000 mm. (C) shows each aberration diagram of Rt = 1000 mm.

  From each aberration diagram, the zoom lens according to the fourth example has excellent imaging performance with various aberrations corrected well from the wide-angle end state to the telephoto end state and during image stabilization correction in each state. I understand that.

(5th Example)
FIG. 13 is a diagram illustrating a lens configuration of a zoom lens according to Example 5. W represents a wide-angle end state, M represents an intermediate focal length state, and T represents a telephoto end state.

  The zoom lens according to Example 5 includes, in order from the object side, a first lens group G1 having a positive refractive power, a second lens group G2 having a negative refractive power, and a rear group Gr including an optical element Oc having a positive refractive power. , A dust-proof glass G, an optical low-pass filter OLPF, and a cover glass CG of a solid-state imaging device disposed on the image plane I.

  The first lens group G1 is composed of, in order from the object side, a biconvex positive lens L11, a negative meniscus lens L12 having a convex surface facing the object side, and a positive meniscus lens L13 having a convex surface facing the object side. It consists of a lens.

  The second lens group G2 includes, in order from the object side, a cemented lens formed by cementing a biconcave negative lens L21, a biconcave negative lens L22, and a positive meniscus lens L23 having a convex surface toward the object side, and an image. It is composed of a negative meniscus lens L24 having a convex surface facing the surface I side.

  The optical element Oc (rear group Gr) includes, in order from the object side, a first partial group Gr1 having a positive refractive power, an aperture stop S1, a second partial group Gr2 having a positive refractive power, and a third partial group having a negative refractive power. Consists of Gr3, field stop S2, and fourth subgroup Gr4 having positive refracting power. Focusing from an infinite object point to a close object point by moving the first subgroup Gr1 along the optical axis The third subgroup Gr3 is moved so as to include a component in a direction orthogonal to the optical axis, thereby performing image shift on the image plane I.

  The first partial group Gr1 includes a biconvex positive lens Lr1.

  The second partial group Gr2 includes, in order from the object side, a cemented lens formed by cementing a biconvex positive lens Lr2 and a negative meniscus lens Lr3 having a convex surface facing the image plane I, and a biconvex positive lens Lr4. And a cemented lens formed by cementing a biconcave negative lens Lr5 and a biconvex positive lens Lr6.

  The third partial group Gr3 includes, in order from the object side, a cemented lens formed by cementing a biconvex positive lens Lr7 and a biconcave negative lens Lr8.

  The fourth partial group Gr4 includes, in order from the object side, a biconvex positive lens Lr9 and a negative meniscus lens Lr10 having a convex surface directed toward the image plane I side.

  In the zoom lens according to Example 5, when zooming from the wide-angle end state W to the telephoto end state T, the first lens group G1 moves to the object side, and the second lens group G2 has a concave shape on the object side. The optical element Oc (rear group Gr) moves to the object side along the locus along the optical axis.

  Further, the diagonal image height IH from the center of the solid-state imaging device of the fifth embodiment to the diagonal is 8.5 mm.

  Table 5 below shows specification values of the zoom lens of the fifth example.

(Table 5)
(Overall specifications)
(W) (M) (T)
F 30.00 60.00 107.00
FNO 4.3 4.8 5.8

(Surface data)
Surface number rd nd νd
Object ∞
1) 107.0898 2.5000 1.518230 58.89
2) -99.2726 0.1000
3) 28.8641 1.1000 1.784700 26.30
4) 19.4065 4.4000 1.497820 82.56
5) 623.6707 (variable)
6) -101.6830 1.0000 1.741000 52.67
7) 24.6928 1.1000
8) -64.6171 1.0000 1.741000 52.67
9) 11.7906 2.2000 1.846660 23.78
10) 114.2322 1.2000
11) -18.8537 1.0000 1.741000 52.67
12) -731.1191 (variable)
13) 56.9161 1.8000 1.516800 64.12
14) -26.1469 (variable)
15> (Aperture) ∞ 0.1000
16) 31.5479 3.6000 1.497820 82.56
17) -15.1490 1.1000 1.801000 34.96
18) -67.0657 0.1000
19) 13.3178 3.2000 1.517420 52.32
20) -143.8096 2.1000
21) -114.9972 1.1000 1.846660 23.78
22) 34.8934 2.2000 1.487490 70.45
23) -54.4846 2.8255
24) 106.3359 2.0000 1.805180 25.43
25) -15.0924 0.5000 1.804400 39.57
26) 15.0522 1.4000
27) (Field stop) ∞ 1.7841
28) 20.5121 2.1000 1.647690 33.79
29) -30.0605 1.1000
30) -10.0058 1.0000 1.795000 45.30
31) -21.5527 (variable)
32) ∞ 0.5000 1.516800 64.12
33) ∞ 4.6000
34) ∞ 1.8700 1.516800 64.12
35) ∞ 0.3000
36) ∞ 0.7000 1.516800 64.12
37) ∞ Bf
Image plane ∞

(Variable interval during focusing)
Focusing at infinity Focusing at close range
(W) (M) (T) (W) (M) (T)
F, β 30.00000 60.00000 107.00000 -0.03154 -0.06033 -0.10411
D0 ∞ ∞ ∞ 916.5652 906.2131 897.7633
d 5 2.22767 12.97537 16.95514 2.22767 12.97537 16.95514
d12 11.90233 7.23556 2.37155 12.28749 8.32923 4.36364
d14 3.29604 3.29604 3.29604 2.91088 2.20237 1.30395
d31 13.92910 18.20035 27.53438 13.92910 18.20035 27.53438
Bf 0.50000 0.50000 0.50000 0.50000 0.50000 0.50000
TL 83.43475 93.78691 102.23670 83.43476 93.78690 102.23670

(Moving amount of image stabilization lens and amount of image plane movement during image stabilization)
Focusing at infinity Focusing at close range
(W) (M) (T) (W) (M) (T)
F, β 30.00000 60.00000 107.00000 -0.03154 -0.06033 -0.10411
Lens ± 0.128 ± 0.221 ± 0.303 ± 0.128 ± 0.221 ± 0.303
Image plane ± 0.157 ± 0.314 ± 0.560 ± 0.157 ± 0.314 ± 0.560

(Lens group data)
Group Start surface Focal length
G1 1 +45.606
G2 6 -10.732
Gr 13 +16.308

(Values for conditional expressions)
(1) Fb1 / Fb234 = 0.909
(2) (Fb1 + Fb234) × Fb0 / (Fb1 × Fb234) = 0.891
(3) | Fall / Ff | = 0.558

  FIGS. 14A and 14B are graphs showing various aberrations of the zoom lens according to the fifth example in the infinite focus state and lateral aberrations at the time of image stabilization. FIG. 14A is a wide-angle end state, and FIG. 14B is an intermediate focal length state. (C) shows aberration diagrams in the telephoto end state. FIGS. 15A and 15B are graphs showing various aberrations of the zoom lens according to Example 5 in the close-up shooting distance state and lateral aberrations during image stabilization. FIG. 15A shows Rw = 1000 mm, and FIG. 15B shows Rm = 1000 mm. (C) shows each aberration diagram of Rt = 1000 mm.

  From each aberration diagram, the zoom lens according to Example 5 has excellent imaging performance with various aberrations corrected satisfactorily from the wide-angle end state to the telephoto end state and during image stabilization correction in each state. I understand that.

  As described above, according to the present embodiment, a focusing lens and an anti-vibration lens are arranged in the same lens group (optical element) to achieve a small zoom lens having high imaging performance. Can do.

  In the above embodiment, all the lens groups are moved at the time of zooming. However, what is intended by the present application is not limited to this zooming method. For example, the first lens unit may be fixed in order to make the zooming mechanism of the first lens unit less decentered and to be advantageous for increasing the aperture ratio.

  Further, the optical element may be fixed so that the main drive mechanism can be arranged on the fixed cylinder. With this configuration, the assembly adjustment can be simplified.

  In the fourth example, the third lens group in the rear group has a negative refractive power, but may have a positive refractive power.

  In each of the above embodiments, the first partial group of the rear group is composed of a single biconvex positive lens. However, in order to correct chromatic aberration better, the first partial group may be configured to have an uneven structure. good.

  Moreover, although the three-group configuration is shown in the embodiment, the present invention can also be applied to other group configurations such as a 4-group or 5-group. Specifically, a configuration in which a lens or a lens group is added to the most object side or the most image plane side of the zoom lens of the present application may be used. The lens group refers to a portion having at least one lens separated by an air interval.

  In the zoom lens of the present application, the focusing lens group for focusing from an infinite object point to a short-distance object point can also be applied to autofocus. It is also suitable for driving with a sonic motor. In particular, in the zoom lens of the present application, it is preferable that at least a part of the optical elements is a focusing lens group.

  In the zoom lens of the present application, an image generated by camera shake by moving the anti-vibration lens group so as to include a component perpendicular to the optical axis, or rotating (swinging) in the in-plane direction including the optical axis. It can also be configured to correct blurring.

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

  In the zoom lens of the present application, it is preferable that the aperture stop be disposed in front of or behind the first partial group of the optical elements. However, a lens frame may be used instead of providing a member as the aperture stop. .

  Further, an antireflection film having a high transmittance in a wide wavelength range may be provided on the lens surface of the lens constituting the zoom lens of the present application. Thereby, flare and ghost can be reduced, and high optical performance with high contrast can be achieved.

  The zoom lens according to this embodiment has a zoom ratio of about 2.5 to 7.0.

  In the zoom lens of the present application, the first lens group may have only one positive lens component, but the first lens group preferably has two positive lens components.

  In the zoom lens of the present application, the second lens group may have two negative lens components, but the second lens group preferably has three negative lens components.

  In the zoom lens of the present application, it is preferable that the rear group has three positive lens components and one negative lens component. In the rear group, it is preferable to arrange the lens components in order of positive / negative / positive from the object side with an air gap interposed therebetween.

  Next, a camera having a zoom lens according to an embodiment will be described with reference to the drawings. FIG. 16 shows an electronic still camera equipped with the zoom lens according to the embodiment, where (a) shows a front view and (b) shows a rear view. FIG. 17 is a cross-sectional view taken along the line AA in FIG.

  16 and 17, in the electronic still camera 1 (hereinafter simply referred to as a camera), when a power button (not shown) is pressed, a shutter (not shown) of the photographic lens 2 is opened, and light from a subject (not shown) emits light from the photographic lens. 2 is focused and imaged on an image sensor C (for example, CCD, CMOS, etc.) disposed on the image plane I. The subject image formed on the image sensor C is displayed on the liquid crystal monitor 3 disposed on the back surface of the camera 1. The photographer determines the composition of the subject image while looking at the liquid crystal monitor 3, and then presses the release button 4 to photograph the subject image with the image sensor C, and records and saves it in a memory (not shown). At this time, blurring of the camera 1 caused by camera shake or the like is detected by an angular velocity sensor (not shown) built in the camera 1 or the taking lens barrel, and a first vibration lens is provided on the taking lens 2 by an anti-vibration mechanism (not shown). The three subgroups Gr3 are shifted in the direction perpendicular to the optical axis of the taking lens 2 to correct image blur on the image plane I caused by camera shake.

  The photographic lens 2 is composed of the zoom lens according to the embodiment. The camera 1 also includes an auxiliary light emitting unit 5 that emits auxiliary light when the subject is dark, and a zoom lens that is the photographing lens 2 when zooming from the wide-angle end state (W) to the telephoto end state (T). A wide (W) -tele (T) button 6 and function buttons 7 used for setting various conditions of the camera 1 are arranged.

  Thus, the camera 1 including the zoom lens according to the embodiment is configured.

  The outline of the manufacturing method of the zoom lens of the present application will be described below with reference to FIG. FIG. 18 is a diagram illustrating a manufacturing method of the zoom lens of the present application.

  The zoom lens manufacturing method according to the present application includes, in order from the object side, a zoom lens having a first lens group having a positive refractive power, a second lens group having a negative refractive power, and a rear group including an optical element having a positive refractive power. This manufacturing method includes steps S1 and S2 shown in FIG.

Step S1:
Step S1 includes, in order from the object side, a first partial group having positive refractive power, a second partial group having positive refractive power, a third partial group having negative refractive power, and a fourth partial group having positive refractive power. Prepare an optical element with positive refractive power,
In order from the object side, an optical member including a first lens group having a positive refractive power, a second lens group having a negative refractive power, and a rear group including the optical element is disposed in a cylindrical lens barrel.

Step S2:
Step S2 is a mechanism for changing the distance between the first lens group, the second lens group, and the rear group when zooming from the wide-angle end state to the telephoto end state;
A mechanism for moving the first partial group along the optical axis when focusing from an infinite object point to a short-distance object point;
When the image shift is performed on the image plane, a mechanism for moving the third partial group so as to include a component in a direction orthogonal to the optical axis is disposed.

  According to the zoom lens manufacturing method of the present application, it is possible to manufacture a zoom lens having a small size and high imaging performance by disposing the focusing lens and the image stabilizing lens in the same lens group.

  In addition, each said Example has shown the specific example of this invention, and this invention is not limited to these.

G1 1st lens group G2 2nd lens group Gr Rear group Oc Optical element Gr1 1st partial group Gr2 2nd partial group Gr3 3rd partial group Gr4 4th partial group I Image surface 1 Electronic still camera 2 Imaging lens (zoom lens)

Claims (11)

In order from the object side, a first lens group having a positive refractive power, a second lens group having a negative refractive power, and a rear group including an optical element having a positive refractive power,
By changing the interval of each group, zooming from the wide-angle end state to the telephoto end state,
The optical element includes, in order from the object side, a first partial group having a positive refractive power, a second partial group having a positive refractive power, a third partial group having a negative refractive power, and a fourth partial group having a positive refractive power. Have
Focusing from an infinite object point to a short distance object point by moving the first subgroup along the optical axis,
A zoom lens, wherein the third partial group is moved so as to include a component in a direction orthogonal to the optical axis.   The distance in the optical axis direction between the second partial group and the third partial group and the distance in the optical axis direction between the third partial group and the fourth partial group are always fixed. The zoom lens according to 1.   3. The zoom lens according to claim 1, wherein the second partial group includes at least three positive lenses and at least one negative lens. The zoom lens according to any one of claims 1 to 3, wherein the following condition is satisfied.
0.60 <Fb1 / Fb234 <1.70
However,
Fb1: Focal length of the first partial group Fb234: Composite focal length of the second partial group, the third partial group, and the fourth partial group The zoom lens according to claim 1, wherein the following condition is satisfied.
0.60 <(Fb1 + Fb234) × Fb0 / (Fb1 × Fb234) <1.40
However,
Fb1: Focal length of the first partial group Fb234: Composite focal length of the second partial group, the third partial group, and the fourth partial group Fb0: Focal length of the optical element at the time of focusing on infinity The zoom lens according to claim 1, wherein the following condition is satisfied.
| Fall / Ff | <1.30
However,
Fall: focal length of the zoom lens at the time of focusing on infinity Ff: an optical system including the most image side lens of the first partial group and all the lenses arranged on the object side from the image side lens Combined focal length when focusing on infinity   The zoom lens according to claim 1, wherein the rear group includes only the optical element.   The zoom lens according to any one of claims 1 to 6, wherein the rear group includes two lens groups, and an image side lens group of the two lens groups includes the optical element.   9. The zoom lens according to claim 1, wherein an aperture stop is disposed at a position adjacent to the object side or the image side of the first partial group.   An optical apparatus comprising the zoom lens according to claim 1. In order from the object side, in a method of manufacturing a zoom lens having a first lens group having a positive refractive power, a second lens group having a negative refractive power, and a rear group including an optical element having a positive refractive power,
In order from the object side, a first partial group having positive refractive power, a second partial group having positive refractive power, a third partial group having negative refractive power, and a fourth partial group having positive refractive power are arranged on the optical element. And
By changing the distance between the first lens group, the second lens group, and the rear group, zooming from the wide-angle end state to the telephoto end state is performed.
Focusing from an infinite object point to a short distance object point by moving the first subgroup along the optical axis,
Arranging the first lens group, the second lens group, and the rear group in order from the object side so as to move the third partial group so as to include a component in a direction orthogonal to the optical axis. A zoom lens manufacturing method characterized by the above.

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