JP6683279B2 - Zoom lens and optical equipment - Google Patents

Description

The present invention relates to a zoom lens and an optical device suitable for a photographic camera, an electronic still camera, a video camera, etc.
The present application claims priority based on Japanese Patent Application No. 2015-017209 filed on January 30, 2015, and the content thereof is incorporated herein.

  Conventionally, a wide-angle variable power optical system has been proposed (for example, refer to Patent Document 1).

JP, 2007-279077, A

  However, the conventional variable-magnification optical system as described above has a problem that the F number is bright and it is not possible to sufficiently meet the demand for an optical system having high optical performance.

One aspect of the present invention is, in order from the object side along the optical axis, a first lens group having a negative refractive power, a second lens group having a positive refractive power, and a third lens having a negative refractive power. The lens group, the fourth lens group having a positive refracting power, and the fifth lens group having a positive refracting power are substantially composed of five lens groups. The distance between the second lens group changes, the distance between the second lens group and the third lens group changes, the distance between the third lens group and the fourth lens group changes, and The distance between the fourth lens group and the fifth lens group changes, and a zoom lens satisfying the following conditional expression is provided.
3.171 ≦ f5 / (− f1) ≦ 4.162
0.200 <f5 / f4 <2.600
However,
f5: focal length of the fifth lens group f1: focal length of the first lens group f4: focal length of the fourth lens group

Further, according to one embodiment of the present invention, a first lens group having a negative refracting power, a second lens group having a positive refracting power, and a second lens group having a negative refracting power are provided in order from the object side along the optical axis. Three lens groups, a fourth lens group having a positive refracting power, and a fifth lens group having a positive refracting power, which substantially comprises five lens groups, and the first lens upon zooming. The distance between the lens group and the second lens group changes, the distance between the second lens group and the third lens group changes, the distance between the third lens group and the fourth lens group changes, A distance between the fourth lens group and the fifth lens group is changed, and a zoom lens satisfying the following conditional expression is provided.
6.234 ≦ f5 / (− f1) <10.000
0.200 <f5 / f4 <2.600
However,
f5: focal length of the fifth lens group f1: focal length of the first lens group f4: focal length of the fourth lens group

1A, 1B, and 1C are cross-sectional views of the zoom lens according to Example 1 in a wide-angle end state, an intermediate focal length state, and a telephoto end state, respectively. 2 (a), 2 (b), and 2 (c) show focusing of an object at infinity in the wide-angle end state, intermediate focal length state, and telephoto end state of the zoom lens according to Example 1, respectively. FIG. 7 is a diagram of various types of aberration of FIG. FIG. 3A, FIG. 3B, and FIG. 3C show focusing of a short-distance object in the wide-angle end state, the intermediate focal length state, and the telephoto end state of the zoom lens according to Example 1, respectively. FIG. 7 is a diagram of various types of aberration of FIG. 4 (a), 4 (b), and 4 (c) are the meridional laterals during image stabilization in the wide-angle end state, intermediate focal length state, and telephoto end state of the zoom lens according to Example 1, respectively. It is an aberration diagram. FIG. 5A, FIG. 5B, and FIG. 5C are cross-sectional views of the zoom lens according to Example 2 in the wide-angle end state, the intermediate focal length state, and the telephoto end state, respectively. 6 (a), 6 (b), and 6 (c) show focusing of an object at infinity in the wide-angle end state, the intermediate focal length state, and the telephoto end state of the zoom lens according to the second example, respectively. FIG. 7 is a diagram of various types of aberration of FIG. 7 (a), 7 (b), and 7 (c) show focusing of a short-distance object in the wide-angle end state, intermediate focal length state, and telephoto end state of the zoom lens according to Example 2, respectively. FIG. 7 is a diagram of various types of aberration of FIG. FIG. 8A, FIG. 8B, and FIG. 8C are meridional laterals during image stabilization in the wide-angle end state, the intermediate focal length state, and the telephoto end state of the zoom lens according to the second example, respectively. It is an aberration diagram. 9A, 9B, and 9C are cross-sectional views of the zoom lens according to Example 3 in the wide-angle end state, the intermediate focal length state, and the telephoto end state, respectively. FIG. 10A, FIG. 10B, and FIG. 10C are respectively for focusing the object at infinity in the wide-angle end state, the intermediate focal length state, and the telephoto end state of the zoom lens according to the third example. FIG. 7 is a diagram of various types of aberration of FIG. 11 (a), 11 (b), and 11 (c) show focusing of a short-distance object in the wide-angle end state, intermediate focal length state, and telephoto end state of the zoom lens according to the third example, respectively. FIG. 7 is a diagram of various types of aberration of FIG. 12 (a), 12 (b), and 12 (c) are the meridional laterals during image stabilization in the wide-angle end state, the intermediate focal length state, and the telephoto end state of the zoom lens according to Example 3, respectively. It is an aberration diagram. 13A, 13B, and 13C are cross-sectional views of the zoom lens according to Example 4 in the wide-angle end state, the intermediate focal length state, and the telephoto end state, respectively. 14 (a), 14 (b), and 14 (c) show focusing of an object at infinity in the wide-angle end state, intermediate focal length state, and telephoto end state of the zoom lens according to Example 4, respectively. FIG. 7 is a diagram of various types of aberration of FIG. 15 (a), 15 (b), and 15 (c) show focusing of a short-distance object in the wide-angle end state, intermediate focal length state, and telephoto end state of the zoom lens according to Example 4, respectively. FIG. 7 is a diagram of various types of aberration of FIG. 16 (a), 16 (b), and 16 (c) are the meridional laterals during image stabilization in the wide-angle end state, intermediate focal length state, and telephoto end state of the zoom lens according to Example 4, respectively. It is an aberration diagram. 17A, 17B, and 17C are cross-sectional views of the zoom lens according to the fifth example in a wide-angle end state, an intermediate focal length state, and a telephoto end state, respectively. 18 (a), 18 (b), and 18 (c) show focusing of an object at infinity in the wide-angle end state, intermediate focal length state, and telephoto end state of the zoom lens according to Example 5, respectively. FIG. 7 is a diagram of various types of aberration of FIG. 19 (a), 19 (b), and 19 (c) show focusing of a short-distance object in the wide-angle end state, intermediate focal length state, and telephoto end state of the zoom lens according to Example 5, respectively. FIG. 7 is a diagram of various types of aberration of FIG. 20 (a), 20 (b), and 20 (c) are the meridional laterals during image stabilization in the wide-angle end state, intermediate focal length state, and telephoto end state of the zoom lens according to Example 5, respectively. It is an aberration diagram. 21 (a), 21 (b), and 21 (c) are cross-sectional views of the zoom lens according to Example 6 in the wide-angle end state, the intermediate focal length state, and the telephoto end state, respectively. 22 (a), 22 (b), and 22 (c) show focusing of an object at infinity in the wide-angle end state, intermediate focal length state, and telephoto end state of the zoom lens according to Example 6, respectively. FIG. 7 is a diagram of various types of aberration of FIG. 23 (a), 23 (b), and 23 (c) show focusing of a short-distance object in the wide-angle end state, intermediate focal length state, and telephoto end state of the zoom lens according to Example 6, respectively. FIG. 7 is a diagram of various types of aberration of FIG. 24 (a), 24 (b), and 24 (c) are the meridional laterals during image stabilization in the wide-angle end state, the intermediate focal length state, and the telephoto end state of the zoom lens according to Example 6, respectively. It is an aberration diagram. 25 (a), 25 (b), and 25 (c) are cross-sectional views of the zoom lens according to Example 7 in the wide-angle end state, the intermediate focal length state, and the telephoto end state, respectively. 26 (a), 26 (b), and 26 (c) show focusing of an object at infinity in the wide-angle end state, intermediate focal length state, and telephoto end state of the zoom lens according to Example 7, respectively. FIG. 7 is a diagram of various types of aberration of FIG. 27 (a), 27 (b), and 27 (c) show focusing of a short-distance object in the wide-angle end state, intermediate focal length state, and telephoto end state of the zoom lens according to Example 7, respectively. FIG. 7 is a diagram of various types of aberration of FIG. 28 (a), 28 (b), and 28 (c) are the meridional laterals during image stabilization in the wide-angle end state, the intermediate focal length state, and the telephoto end state of the zoom lens according to Example 7, respectively. It is an aberration diagram. 29A, 29B, and 29C are cross-sectional views of the zoom lens according to Example 8 in the wide-angle end state, the intermediate focal length state, and the telephoto end state, respectively. 30 (a), 30 (b), and 30 (c) show focusing of an object at infinity in the wide-angle end state, intermediate focal length state, and telephoto end state of the zoom lens according to Example 8, respectively. FIG. 7 is a diagram of various types of aberration of FIG. 31 (a), 31 (b), and 31 (c) show focusing of a short-distance object in the wide-angle end state, intermediate focal length state, and telephoto end state of the zoom lens according to Example 8, respectively. FIG. 7 is a diagram of various types of aberration of FIG. 32 (a), 32 (b), and 32 (c) are the meridional laterals during image stabilization in the wide-angle end state, the intermediate focal length state, and the telephoto end state of the zoom lens according to Example 8, respectively. It is an aberration diagram. 33A, 33B, and 33C are cross-sectional views of the zoom lens according to Example 9 in the wide-angle end state, the intermediate focal length state, and the telephoto end state, respectively. 34 (a), 34 (b), and 34 (c) show focusing of an object at infinity in a wide-angle end state, an intermediate focal length state, and a telephoto end state of the zoom lens according to Example 9, respectively. FIG. 7 is a diagram of various types of aberration of FIG. 35 (a), 35 (b), and 35 (c) show focusing of a short-distance object in the wide-angle end state, intermediate focal length state, and telephoto end state of the zoom lens according to the ninth example, respectively. FIG. 7 is a diagram of various types of aberration of FIG. 36 (a), 36 (b), and 36 (c) are respectively the meridional lateral sides at the time of image stabilization in the wide-angle end state, the intermediate focal length state, and the telephoto end state of the zoom lens according to the ninth example. It is an aberration diagram. 37 (a), 37 (b), and 37 (c) are cross-sectional views of the zoom lens according to Example 10 in the wide-angle end state, the intermediate focal length state, and the telephoto end state, respectively. 38 (a), 38 (b), and 38 (c) show focusing of an object at infinity in the wide-angle end state, intermediate focal length state, and telephoto end state of the zoom lens according to Example 10, respectively. FIG. 7 is a diagram of various types of aberration of FIG. 39 (a), 39 (b), and 39 (c) show focusing of a short-distance object in a wide-angle end state, an intermediate focal length state, and a telephoto end state of the zoom lens according to Example 10, respectively. FIG. 7 is a diagram of various types of aberration of FIG. 40 (a), 40 (b), and 40 (c) are the meridional laterals during image stabilization in the wide-angle end state, intermediate focal length state, and telephoto end state of the zoom lens according to Example 10, respectively. It is an aberration diagram. 41A, 41B, and 41C are cross-sectional views of the zoom lens according to Example 11 in the wide-angle end state, the intermediate focal length state, and the telephoto end state, respectively. 42 (a), 42 (b), and 42 (c) show focusing of an object at infinity in the wide-angle end state, intermediate focal length state, and telephoto end state of the zoom lens according to Example 11, respectively. FIG. 7 is a diagram of various types of aberration of FIG. 43 (a), 43 (b), and 43 (c) show focusing of a short-distance object in the wide-angle end state, intermediate focal length state, and telephoto end state of the zoom lens according to Example 11, respectively. FIG. 7 is a diagram of various types of aberration of FIG. 44 (a), 44 (b), and 44 (c) are the meridional laterals during image stabilization in the wide-angle end state, the intermediate focal length state, and the telephoto end state of the zoom lens according to Example 11, respectively. It is an aberration diagram. FIG. 45 is a schematic diagram showing the structure of a camera including a zoom lens. FIG. 46 is a diagram showing the outline of the method of manufacturing the zoom lens.

  Hereinafter, a zoom lens, an optical device, and a method for manufacturing the zoom lens will be described with respect to the embodiments. First, a zoom lens according to an embodiment will be described.

A zoom lens according to an embodiment includes, in order from the object side along an optical axis, a first lens group having a negative refractive power, a second lens group having a positive refractive power, and a first lens group having a negative refractive power. It has three lens groups, a fourth lens group having a positive refracting power, and a fifth lens group, and during zooming, the distance between the first lens group and the second lens group changes, The distance between the second lens group and the third lens group changes, the distance between the third lens group and the fourth lens group changes, and the distance between the fourth lens group and the fifth lens group changes. Change. In one example, the fifth lens group can have a positive refractive power.
With this configuration, it is possible to realize zooming, and it is possible to achieve excellent aberration correction during zooming.

The zoom lens satisfies the following conditional expression (1).
(1) 1.000 <f5 / (-f1) <10.000
However,
f5: focal length of the fifth lens group f1: focal length of the first lens group

  Conditional expression (1) is a conditional expression for defining an appropriate range of the ratio between the focal length of the fifth lens group and the focal length of the first lens group. By satisfying the conditional expression (1), it is possible to realize a wide-angle brightness with an F number of about F2.8 to F4.0 and satisfactorily correct various aberrations such as spherical aberration.

  When the corresponding value of the conditional expression (1) exceeds the upper limit value, the power of the first lens group with respect to the fifth lens group increases, and it becomes difficult to correct the field curvature and the curvature aberration particularly in the wide-angle end state. There is a nature. In order to secure the effect, it is preferable to set the upper limit of conditional expression (1) to 8.700. Further, in order to further secure the effect, it is preferable that the upper limit value of the conditional expression (1) is set to 7.400.

  On the other hand, when the corresponding value of the conditional expression (1) is less than the lower limit value, the power of the fifth lens group with respect to the first lens group increases, and it becomes difficult to correct the field curvature and the curvature aberration especially in the telephoto end state. Could be. In order to secure the effect, it is preferable to set the lower limit of conditional expression (1) to 1.700. In order to further secure the effect, it is preferable that the lower limit value of conditional expression (1) is set to 2.400.

Further, the zoom lens preferably can satisfy the following conditional expression (2).
(2) 0.300 <| m12 | / fw <5.000
However,
| M12 |: Amount of change in the distance from the wide-angle end state to the telephoto end state on the optical axis from the most image-side lens surface of the first lens group to the most object-side lens surface of the second lens group fw : Focal length of the entire zoom lens system in the wide-angle end state

  Conditional expression (2) relates to the zooming load of the first lens group and the second lens group, from the lens surface closest to the image side of the first lens group with respect to the focal length of the entire zoom lens system in the wide-angle end state. It is a conditional expression for defining an appropriate range of the ratio of the amount of change from the wide-angle end state to the telephoto end state of the distance on the optical axis to the most object side lens surface of the second lens group.

  When the corresponding value of the conditional expression (2) exceeds the upper limit value, the distance between the first lens group and the image plane increases, and particularly the spherical aberration and coma aberration correction burdens of the second lens group increase, Correction of spherical aberration and coma may be difficult. In order to secure the effect, it is preferable to set the upper limit of conditional expression (2) to 4.000. In order to further secure the effect, it is preferable that the upper limit of conditional expression (2) be set to 3.000.

  On the other hand, if the corresponding value of the conditional expression (2) is less than the lower limit value, the variable magnification load of the lens groups other than the first lens group increases, and in particular, the power of the fourth lens group increases, which causes coma aberration. Correction may be difficult. In order to secure the effect, it is preferable to set the lower limit of conditional expression (2) to 0.600. Further, in order to further secure the effect, it is preferable that the lower limit value of conditional expression (2) is set to 0.900.

Further, the zoom lens preferably can satisfy the following conditional expression (3).
(3) 0.200 <f5 / f4 <4.00
However,
f5: focal length of the fifth lens group f4: focal length of the fourth lens group

  Conditional expression (3) is a conditional expression for defining an appropriate range of the ratio between the focal length of the fifth lens group and the focal length of the fourth lens group. When the corresponding value of the conditional expression (3) exceeds the upper limit value, the power of the fourth lens group with respect to the fifth lens group increases, and it may be difficult to correct coma aberration. In order to secure the effect, it is preferable to set the upper limit of conditional expression (3) to 3.300. Further, in order to further secure the effect, it is preferable that the upper limit value of the conditional expression (3) is set to 2.600.

  On the other hand, when the corresponding value of the conditional expression (3) is less than the lower limit value, the power of the fifth lens group with respect to the fourth lens group increases, which may make it difficult to correct the field curvature. In order to secure the effect, it is preferable that the lower limit value of conditional expression (3) be set to 0.350. In order to further secure the effect, it is preferable that the lower limit value of conditional expression (3) be 0.450.

Further, it is preferable that the zoom lens is configured so that at least a part of the lenses in the third lens group can be moved so as to include a component in a direction orthogonal to the optical axis. For example, it is preferable that the zoom lens is configured so that at least two lenses in the third lens group can be moved so as to include a component in a direction orthogonal to the optical axis.
As described above, by configuring at least two lenses in the third lens group to be movable so as to include a component in the direction orthogonal to the optical axis as an anti-vibration lens group, the size of the anti-vibration lens group can be reduced. In addition, it is possible to realize high accuracy, and it is possible to favorably correct decentering coma aberration, decentering field curvature, and eccentric magnification chromatic aberration during image stabilization.

Further, it is preferable that the zoom lens is configured so that at least a part of the lenses in the second lens group can be moved so as to include a component in a direction orthogonal to the optical axis. For example, the zoom lens can preferably be configured so that at least two lenses in the second lens group can be moved so as to include a component in a direction orthogonal to the optical axis.
As described above, by arranging at least two lenses in the second lens group as a vibration-proof lens group so as to be movable so as to include a component in the direction orthogonal to the optical axis, the size of the vibration-proof lens group is reduced. In addition, it is possible to satisfactorily correct eccentric coma aberration, eccentric field curvature, and eccentric magnification chromatic aberration during image stabilization.

Further, it is preferable that the zoom lens is configured so that at least a part of the lenses in the fourth lens group can be moved so as to include a component in a direction orthogonal to the optical axis. For example, it is preferable that the zoom lens is configured so that at least two lenses in the fourth lens group can be moved so as to include a component in a direction orthogonal to the optical axis.
In this way, at least two lenses in the fourth lens group are configured to be movable so as to include a component in the direction orthogonal to the optical axis as a vibration isolation lens group, thereby reducing the size of the vibration isolation lens group. In addition, it is possible to satisfactorily correct eccentric coma aberration, eccentric field curvature, and eccentric magnification chromatic aberration during image stabilization.

Further, the zoom lens is preferably capable of focusing from an object at infinity to a near object by moving at least a part of the lenses in the second lens group along the optical axis. For example, the zoom lens is preferably capable of focusing from an object at infinity to a near object by moving at least two lenses in the second lens group along the optical axis.
With this configuration, the focusing lens group can be downsized, and the variation of chromatic aberration and the variation of field curvature due to focusing can be favorably corrected.

Further, the zoom lens is preferably capable of focusing from an object at infinity to a near object by moving at least a part of the lenses in the third lens group along the optical axis. For example, the zoom lens is preferably capable of focusing from an object at infinity to a near object by moving at least two lenses in the third lens group along the optical axis.
With this configuration, the focusing lens group can be downsized, and the variation of chromatic aberration and the variation of field curvature due to focusing can be favorably corrected.

Further, the zoom lens is preferably capable of focusing from an object at infinity to a near object by moving at least a part of the lenses in the fourth lens group along the optical axis. For example, the zoom lens is preferably capable of focusing from an object at infinity to a near object by moving at least two lenses in the fourth lens group along the optical axis.
With this configuration, the focusing lens group can be downsized, and the variation of chromatic aberration and the variation of field curvature due to focusing can be favorably corrected.

Further, the zoom lens is preferably capable of focusing from an object at infinity to a near object by moving a part or all of the fifth lens group along the optical axis.
With this configuration, it is possible to satisfactorily correct variations in axial chromatic aberration, variations in spherical aberration, and variations in coma due to focusing.

The zoom lens can preferably have an aperture stop between the second lens group and the third lens group.
With this configuration, spherical aberration, coma, and lateral chromatic aberration can be favorably corrected.

  Moreover, the optical device according to the embodiment includes the zoom lens having the above-described configuration. Thereby, it is possible to realize an optical device having a high F number and high optical performance.

Further, in the method for manufacturing a zoom lens according to the embodiment, the first lens group having a negative refractive power, the second lens group having a positive refractive power, and the negative refractive power are sequentially arranged from the object side along the optical axis. A method of manufacturing a zoom lens having a third lens group having a power, a fourth lens group having a positive refractive power, and a fifth lens group, which is configured to satisfy the following conditional expression (1): During zooming, the distance between the first lens group and the second lens group changes, the distance between the second lens group and the third lens group changes, and the third lens group and the third lens group change. The distance between the fourth lens group and the fourth lens group changes, and the distance between the fourth lens group and the fifth lens group changes. In one example, the fifth lens group can have a positive refractive power.
(1) 1.000 <f5 / (-f1) <10.000
However,
f5: focal length of the fifth lens group f1: focal length of the first lens group

  With such a zoom lens manufacturing method, it is possible to manufacture a zoom lens lens having a bright F number and high optical performance.

(Numerical example)
Hereinafter, zoom lenses according to numerical examples will be described with reference to the accompanying drawings.

(First embodiment)
1A, 1B, and 1C are cross-sectional views of the zoom lens according to Example 1 in a wide-angle end state, an intermediate focal length state, and a telephoto end state, respectively.
The arrow below each lens group in FIG. 1A indicates the moving direction of each lens group during zooming from the wide-angle end state to the intermediate focal length state. The arrow below each lens group in FIG. 1B indicates the moving direction of each lens group during zooming from the intermediate focal length state to the telephoto end state.

  As shown in FIG. 1A, the zoom lens according to the present embodiment includes, in order from the object side along the optical axis, a first lens group G1 having a negative refractive power and a second lens group G1 having a positive refractive power. It is composed of a lens group G2, a third lens group G3 having a negative refractive power, a fourth lens group G4 having a positive refractive power, and a fifth lens group G5 having a positive refractive power.

  The first lens group G1 includes, in order from the object side along the optical axis, a negative meniscus lens L11 having a convex surface facing the object side, a negative meniscus lens L12 having a convex surface facing the object side, a biconcave lens L13, and a biconvex lens. And L14. The negative meniscus lens L11 is an aspherical lens in which the object-side lens surface and the image-side lens surface have an aspherical shape.

The second lens group G2 includes, in order from the object side along the optical axis, a second F lens group G2F having a positive refractive power and a second R lens group G2R having a positive refractive power.
The second F lens group G2F includes, in order from the object side along the optical axis, a cemented lens of a biconvex lens L21 and a negative meniscus lens L22 having a concave surface facing the object side, and a negative meniscus lens L23 having a convex surface facing the object side. It consists of The biconvex lens L21 is an aspherical lens having an aspherical surface on the object side.
The second R lens group G2R is composed of, in order from the object side along the optical axis, a cemented lens of a negative meniscus lens L24 having a convex surface facing the object side, a biconvex lens L25, and a negative meniscus lens L26 having a concave surface facing the object side. Has been done.

  The third lens group G3 is composed of an aperture stop S, a cemented lens of a biconcave lens L31 and a positive meniscus lens L32 having a convex surface directed toward the object side, and a flare cut stop FS in order from the object side along the optical axis. Has been done. The positive meniscus lens L32 is an aspherical lens whose lens surface on the image side has an aspherical shape.

  The fourth lens group G4 includes, in order from the object side along the optical axis, a cemented lens of a biconvex lens L41 and a negative meniscus lens L42 having a concave surface facing the object side, and a negative meniscus lens L43 having a convex surface facing the object side. It is composed of a cemented lens with a positive meniscus lens L44 having a convex surface facing the object side. The negative meniscus lens L42 is an aspherical lens having an aspherical surface on the image side.

  The fifth lens group G5 is composed of a positive meniscus lens L51 having a concave surface facing the object side. The positive meniscus lens L51 is an aspherical lens having an aspherical surface on the object side and the image side.

  On the image plane I, an image pickup device (not shown) composed of CCD, CMOS or the like is arranged.

  With the above-described configuration, in the zoom lens according to the present embodiment, the distance between the first lens group G1 and the second lens group G2 decreases during zooming from the wide-angle end state to the telephoto end state, and the second lens group The distance between the lens group G2 and the third lens group G3 increases, the distance between the third lens group G3 and the fourth lens group G4 decreases, and the distance between the fourth lens group G4 and the fifth lens group G5 increases. As described above, the first lens group G1, the second lens group G2, the third lens group G4, and the fourth lens group G4 move along the optical axis with respect to the image plane I. Specifically, during zooming, the first lens group G1 once moves to the image plane I side and then to the object side, the second lens group G2 moves to the object side, and the third lens group G3 moves to the object side. To the object side, the fifth lens group G5 is fixed with respect to the image plane I.

  The aperture stop S is arranged between the second lens group G2 and the third lens group G3, and moves together with the third lens group G3 during zooming from the wide-angle end state to the telephoto end state.

  Further, in the zoom lens according to the present embodiment, by moving the second F lens group G2F to the image plane I side, focusing from an object at infinity to a near object is performed.

  In the zoom lens according to the present embodiment, a cemented lens of the biconcave lens L31 of the third lens group G3 and the positive meniscus lens L32 having a convex surface facing the object side is used as a vibration-proof lens group and a component in a direction orthogonal to the optical axis. By moving in a direction including, the image plane is corrected when the image blur occurs, that is, the image stabilization is performed.

Here, when the focal length of the entire zoom lens system according to the present embodiment is f, and the ratio of the amount of movement of the image on the image plane I to the amount of movement of the image stabilizing lens group during shake correction is K (hereinafter, This ratio is called the image stabilization coefficient K.) In order to correct the rotational shake of the angle θ, the image stabilization lens group may be shifted by (f · tan θ) / K in the direction orthogonal to the optical axis. .
In the wide-angle end state, the zoom lens according to the present example has an image stabilization coefficient K of 0.54 and a focal length of 16.48 (mm) (see Table 1 below), so that 0.81 ° The movement amount of the anti-vibration lens unit for correcting the rotational shake is 0.43 (mm). Further, in the intermediate focal length state, the image stabilization coefficient K is 0.68 and the focal length is 25.21 (mm) (see Table 1 below), so to correct the rotational blur of 0.66 °. The movement amount of the image stabilizing lens unit is 0.42 (mm). Further, in the telephoto end state, the image stabilization coefficient K is 0.85, and the focal length is 33.95 (mm) (see Table 1 below). Therefore, in order to correct the rotational shake of 0.57 °, The movement amount of the image stabilizing lens unit is 0.39 (mm).

Table 1 below lists specifications of the zoom lens according to Example 1.
In [Overall Specifications] in Table 1, f is the focal length of the entire zoom lens system, FNO is the F number, ω is the half angle of view (unit: degrees), Y is the image height, TL is the total length of the optical system, and BF is The back focus is shown respectively. Here, the optical system total length TL is the distance on the optical axis from the lens surface closest to the object in the first lens group G1 to the image plane I. The back focus BF is the distance on the optical axis from the most image-side lens surface in the fifth lens group G5 to the image plane I. Further, W indicates the wide-angle end state, M indicates the intermediate focal length state, and T indicates the telephoto end state.

  In [Surface data], the surface number is the order of the lens surfaces counted from the object side, r is the radius of curvature of the lens surfaces, d is the distance between the lens surfaces, nd is the refractive index for the d line (wavelength λ = 587.6 nm), νd represents the Abbe number for the d line (wavelength λ = 587.6 nm). Further, the object plane is the object plane, the (stop) is the aperture stop S, the (FS) is the flare cut stop FS, and the image plane is the image plane I, respectively. The radius of curvature r = ∞ indicates a plane, and the description of the refractive index d = 1.00000 of air is omitted. When the lens surface is an aspherical surface, the surface number is marked with * and the paraxial radius of curvature is shown in the column of radius of curvature r.

  The [lens group data] shows the starting surface number and the focal length of each lens group.

[Aspherical surface data] indicates an aspherical surface coefficient and a conic constant when the shape of the aspherical surface shown in [Surface data] is expressed by the following equation.
x = (h2 / r) / [1+ {1-κ (h / r) 2} 1/2]
+ A4h4 + A6h6 + A8h8 + A10h10
Here, h is the height in the direction perpendicular to the optical axis, x is the distance along the optical axis direction from the tangent plane of the vertex of the aspherical surface at the height h to the aspherical surface, and κ is the conic constant. , A4, A6, A8 and A10 are aspherical surface coefficients, and r is a radius of curvature of the reference spherical surface (paraxial radius of curvature). Moreover, "E-n" shows "x10-n", for example, "1.234E-05" shows "1.234x10-5." The quadratic aspherical coefficient A2 is 0, and the description is omitted.

In [Variable distance data], f is the focal length of the entire zoom lens system, β is the photographing magnification, and dn (n is an integer) is the variable surface distance between the nth surface and the (n + 1) th surface. Show. Further, d0 indicates the distance from the object to the lens surface closest to the object. It should be noted that W indicates a wide-angle end state, M indicates an intermediate focal length state, T indicates a telephoto end state, infinity indicates an object at infinity, and short distance indicates an object at short distance.
In [Conditional expression corresponding value], the corresponding value of each conditional expression is shown.
Here, “mm” is generally used as the unit of the focal length f, the radius of curvature r, and other lengths described in Table 1. However, the optical system is not limited to this because the same optical performance can be obtained even if the optical system is enlarged or reduced proportionally.

  Note that the reference numerals in Table 1 described above are similarly used in the tables of the respective embodiments described later.

(Table 1) First Example [Overall Specifications]
W M T
f 16.48 25.21 33.95
FNO 2.83 2.83 2.83
ω 54.1 39.9 31.7
Y 21.64 21.64 21.64
TL 162.368 156.100 161.776
BF 18.068 18.076 18.058

[Surface data]
Surface number rd nd νd
Object ∞
* 1) 75.44949 2.000 1.85135 40.1
* 2) 20.28508 6.283
3) 51.06676 2.000 1.90043 37.4
4) 24.72875 14.151
5) -37.47670 2.000 1.49782 82.6
6) 256.37590 0.150
7) 92.17324 6.061 2.00100 29.1
8) -101.88567 (variable)

* 9) 49.32957 10.021 1.61492 58.4
10) -33.33841 1.500 1.61772 49.8
11) -82.04309 0.150
12) 101.37291 1.500 1.51823 58.8
13) 37.71250 (variable)

14) 27.89843 1.500 1.80518 25.4
15) 20.73501 12.485 1.48749 70.3
16) -35.76178 1.500 1.68893 31.2
17) -69.08870 (variable)

18) (Aperture) ∞ 4.000
19) -191.55206 1.500 1.74400 44.8
20) 29.63471 3.611 1.80244 25.6
* 21) 65.28008 1.000
22) (FS) ∞ (variable)

23) 26.78513 6.812 1.49782 82.6
24) -98.18107 1.500 1.88202 37.2
* 25) -107.04814 0.150
26) 135.48608 1.500 1.90043 37.4
27) 20.03626 9.030 1.49782 82.6
28) 2971.25110 (variable)

* 29) -129.34917 5.005 1.76116 50.5
* 30) -43.36071 (BF)
Image plane ∞

[Lens group data]
Starting surface Focal length
G1 1 -26.25
G2 9 39.27
G3 18 -70.00
G4 23 93.83
G5 29 83.59

[Aspherical data]
Surface number: 1
κ = 5.92300E-01
A4 = -2.43736E-06
A6 = 2.64717E-09
A8 = -1.54187E-12
A10 = 5.99784E-16

Surface number: 2
κ = 4.21200E-01
A4 = -6.62142E-06
A6 = 3.27522E-12
A8 = -7.76064E-12
A10 = 9.08049E-15

Surface number: 9
κ = 1.00000E + 00
A4 = -2.887523E-06
A6 = 2.47805E-10
A8 = 0.00000E + 00
A10 = 0.00000E + 00

Surface number: 21
κ = 8.46000E-01
A4 = -5.01566E-07
A6 = -1.49741E-08
A8 = 1.12108E-10
A10 = -2.97302E-13

Surface number: 25
κ = 1.00000E + 00
A4 = 1.18848E-05
A6 = -5.83406E-10
A8 = 2.65926E-11
A10 = -1.81664E-13

Surface number: 29
κ = 1.00000E + 00
A4 = 1.04301E-05
A6 = -2.89394E-08
A8 = 6.51407E-11
A10 = -6.888449E-14

Surface number: 30
κ = 1.00000E + 00
A4 = 1.61530E-05
A6 = -3.59475E-08
A8 = 7.02618E-11
A10 = -6.91220E-14

[Variable interval data]
W M T W M T
Infinity infinity infinity infinity short range short range short range
d 0 ∞ ∞ ∞ 110.00 116.28 110.58
β − − − -0.1212 -0.1798 -0.2542
f 16.48 25.21 33.95 − − −
d 8 29.353 9.442 0.500 34.199 14.324 5.898
d13 6.626 6.626 6.626 1.780 1.743 1.228
d17 2.000 5.729 7.157 2.000 5.729 7.157
d22 7.842 3.616 1.500 7.842 3.616 1.500
d28 3.071 17.203 32.526 3.071 17.203 32.526
BF 18.068 18.076 18.058 18.152 18.261 18.427

[Values corresponding to each conditional expression]
(1) f5 / (-f1) = 3.184
(2) | m12 | /fw=1.751
(3) f5 / f4 = 0.891

2 (a), 2 (b), and 2 (c) show focusing of an object at infinity in the wide-angle end state, intermediate focal length state, and telephoto end state of the zoom lens according to Example 1, respectively. FIG. 7 is a diagram of various types of aberration of FIG.
FIG. 3A, FIG. 3B, and FIG. 3C show focusing of a short-distance object in the wide-angle end state, the intermediate focal length state, and the telephoto end state of the zoom lens according to Example 1, respectively. FIG. 7 is a diagram of various types of aberration of FIG.
4 (a), 4 (b), and 4 (c) are the meridional laterals during image stabilization in the wide-angle end state, intermediate focal length state, and telephoto end state of the zoom lens according to Example 1, respectively. It is an aberration diagram.

  In each aberration diagram, FNO is an F number, A is a ray incident angle, that is, a half angle of view (unit is “°”), NA is a numerical aperture, and H0 is an object height (unit: mm). In the figure, d represents the aberration curve at the d line (wavelength λ = 587.6 nm), g represents the aberration curve at the g line (wavelength λ = 435.8 nm), and those not mentioned are those at the d line. An aberration curve is shown. In the spherical aberration diagram, the F number value corresponding to the maximum aperture is shown, in the astigmatism diagram and the distortion diagram, the maximum value of the half field angle or object height is shown, and in the lateral aberration diagram, each half field angle or each object height is shown. Indicates the value of. In the astigmatism diagram, the solid line shows the sagittal image plane, and the broken line shows the meridional image plane. Further, the lateral aberration diagram shows meridional lateral aberrations for the d-line and the g-line. Note that the same reference numerals as in this example are used in the various aberration diagrams of the examples below.

  As is clear from each aberration diagram, the zoom lens according to Example 1 has various aberrations favorably corrected from the wide-angle end state to the telephoto end state, and also has high optical performance during image stabilization. I understand.

(Second embodiment)
FIG. 5A, FIG. 5B, and FIG. 5C are cross-sectional views of the zoom lens according to Example 2 in the wide-angle end state, the intermediate focal length state, and the telephoto end state, respectively.
The arrow below each lens group in FIG. 5A indicates the moving direction of each lens group during zooming from the wide-angle end state to the intermediate focal length state. The arrow below each lens group in FIG. 5B indicates the moving direction of each lens group during zooming from the intermediate focal length state to the telephoto end state.

  As shown in FIG. 5A, in the zoom lens according to the present embodiment, the first lens group G1 having a negative refractive power and the second lens having a positive refractive power are sequentially arranged from the object side along the optical axis. It is composed of a lens group G2, a third lens group G3 having a negative refractive power, a fourth lens group G4 having a positive refractive power, and a fifth lens group G5 having a positive refractive power.

  The first lens group G1 includes, in order from the object side along the optical axis, a negative meniscus lens L11 having a convex surface directed toward the object side, a negative meniscus lens L12 having a convex surface directed toward the object side, a biconcave lens L13, and a biconvex lens. And L14. The negative meniscus lens L11 is an aspherical lens in which the object-side lens surface and the image-side lens surface have an aspherical shape.

The second lens group G2 includes, in order from the object side along the optical axis, a second F lens group G2F having a positive refractive power and a second R lens group G2R having a positive refractive power.
The second F lens group G2F includes, in order from the object side along the optical axis, a cemented lens of a biconvex lens L21 and a negative meniscus lens L22 having a concave surface facing the object side, and a negative meniscus lens L23 having a convex surface facing the object side. It consists of The biconvex lens L21 is an aspherical lens having an aspherical surface on the object side.
The second R lens group G2R is composed of, in order from the object side along the optical axis, a cemented lens of a negative meniscus lens L24 having a convex surface facing the object side, a biconvex lens L25, and a negative meniscus lens L26 having a concave surface facing the object side. Has been done.

  The third lens group G3 is composed of an aperture stop S, a cemented lens of a biconcave lens L31 and a positive meniscus lens L32 having a convex surface directed toward the object side, and a flare cut stop FS in order from the object side along the optical axis. Has been done. The positive meniscus lens L32 is an aspherical lens whose lens surface on the image side has an aspherical shape.

  The fourth lens group G4 includes, in order from the object side along the optical axis, a cemented lens of a biconvex lens L41 and a negative meniscus lens L42 having a concave surface facing the object side, and a negative meniscus lens L43 having a convex surface facing the object side. It is composed of a cemented lens with a positive meniscus lens L44 having a convex surface facing the object side. The negative meniscus lens L42 is an aspherical lens having an aspherical surface on the image side.

  The fifth lens group G5 is composed of a positive meniscus lens L51 having a concave surface facing the object side. The positive meniscus lens L51 is an aspherical lens having an aspherical surface on the object side and the image side.

  On the image plane I, an image pickup device (not shown) composed of CCD, CMOS or the like is arranged.

  With the above-described configuration, in the zoom lens according to the present embodiment, the distance between the first lens group G1 and the second lens group G2 decreases during zooming from the wide-angle end state to the telephoto end state, and the second lens group The distance between the lens group G2 and the third lens group G3 increases, the distance between the third lens group G3 and the fourth lens group G4 decreases, and the distance between the fourth lens group G4 and the fifth lens group G5 increases. As described above, the first lens group G1, the second lens group G2, the third lens group G4, and the fourth lens group G4 move along the optical axis with respect to the image plane I. Specifically, during zooming, the first lens group G1 once moves to the image plane I side and then to the object side, and the second lens group G2 and the fourth lens group G4 move integrally to the object side. The third lens group G3 moves toward the object side, and the fifth lens group G5 is fixed with respect to the image plane I.

  The aperture stop S is arranged between the second lens group G2 and the third lens group G3, and moves together with the third lens group G3 during zooming from the wide-angle end state to the telephoto end state.

  Further, in the zoom lens according to the present embodiment, by moving the second F lens group G2F to the image plane I side, focusing from an object at infinity to a near object is performed.

  In the zoom lens according to the present embodiment, a cemented lens of the biconcave lens L31 of the third lens group G3 and the positive meniscus lens L32 having a convex surface facing the object side is used as a vibration-proof lens group and a component in a direction orthogonal to the optical axis. By moving in a direction including, the image plane is corrected when the image blur occurs, that is, the image stabilization is performed.

Here, when the focal length of the entire zoom lens system according to the present embodiment is f and the ratio of the amount of movement of the image on the image plane I to the amount of movement of the image stabilizing lens group during blur correction is K, the angle is In order to correct the rotational shake of θ, it is sufficient to shift the antivibration lens group by (f · tan θ) / K in the direction orthogonal to the optical axis.
In the wide-angle end state, the zoom lens according to the present example has a vibration isolation coefficient K of 0.56 and a focal length of 16.48 (mm) (see Table 2 below), so that 0.81 ° The movement amount of the anti-vibration lens unit for correcting the rotational shake is 0.42 (mm). Further, in the intermediate focal length state, the image stabilization coefficient K is 0.70 and the focal length is 25.21 (mm) (see Table 2 below), so to correct the rotational shake of 0.66 °. The movement amount of the image stabilizing lens unit is 0.41 (mm). In addition, in the telephoto end state, the image stabilization coefficient K is 0.87 and the focal length is 33.95 (mm) (see Table 2 below). Therefore, in order to correct the rotational shake of 0.57 °, The movement amount of the image stabilizing lens unit is 0.38 (mm).

  Table 2 below lists specifications of the zoom lens according to the second example.

(Table 2) Second embodiment [Overall specifications]
W M T
f 16.48 25.21 33.95
FNO 2.83 2.83 2.83
ω 54.0 40.0 31.8
Y 21.64 21.64 21.64
TL 162.361 156.840 162.363
BF 18.070 18.065 18.063

[Surface data]
Surface number rd nd νd
Object ∞

* 1) 73.22991 2.000 1.85135 40.1
* 2) 19.62926 7.474
3) 61.15202 2.000 1.90043 37.4
4) 26.50584 12.785
5) -37.55896 2.000 1.49782 82.6
6) 312.93830 0.150
7) 97.61558 6.381 2.00100 29.1
8) -90.94529 (variable)

* 9) 45.42754 8.894 1.58313 59.4
10) -33.86178 1.500 1.65160 58.6
11) -73.70296 1.496
12) 108.06528 1.500 1.51742 52.2
13) 36.32590 (variable)

14) 27.56863 1.500 1.84416 24.0
15) 20.91099 12.393 1.48749 70.3
16) -40.66843 1.500 1.80328 25.5
17) -63.71042 (variable)

18) (Aperture) ∞ 3.500
19) -208.49060 1.500 1.74400 44.8
20) 26.99771 3.953 1.80244 25.6
* 21) 62.64116 1.000
22) (FS) ∞ (variable)

23) 26.9 1271 7.631 1.49782 82.6
24) -57.70103 1.500 1.88202 37.2
* 25) -93.99278 0.150
26) 62.42449 1.500 1.90043 37.4
27) 19.07512 7.749 1.49782 82.6
28) 83.05930 (variable)

* 29) -135.00000 5.076 1.77250 49.5
* 30) -44.25074 (BF)
Image plane ∞

[Lens group data]
Starting surface Focal length
G1 1 -26.24
G2 9 40.29
G3 18 -70.00
G4 23 92.95
G5 29 83.19

[Aspherical data]
Surface number: 1
κ = 7.56000E-02
A4 = -2.78471E-06
A6 = 3.86364E-09
A8 = -2.69774E-12
A10 = 9.05111E-16

Surface number: 2
κ = 1.77500E-01
A4 = -2.58137E-06
A6 = 2.51888E-09
A8 = 2.34244E-12
A10 = 1.66721E-16

Surface number: 9
κ = 1.00000E + 00
A4 = -2.97350E-06
A6 = -1.01164E-09
A8 = 5.03482E-12
A10 = -6.996957E-15

Surface number: 21
κ = 1.27800E + 00
A4 = -2.19664E-07
A6 = -2.34247E-08
A8 = 1.80346E-10
A10 = -4.74051E-13

Surface number: 25
κ = 1.00000E + 00
A4 = 1.15418E-05
A6 = 5.82895E-09
A8 = -4.75474E-12
A10 = -1.24299E-13

Surface number: 29
κ = 1.00000E + 00
A4 = 1.07645E-05
A6 = -4.55569E-08
A8 = 1.31690E-10
A10 = 1.37085E-13

Surface number: 30
κ = 1.00000E + 00
A4 = 1.60203E-05
A6 = -5.49184E-08
A8 = 1.40358E-10
A10 = -1.35750E-13

[Variable interval data]
W M T W M T
Infinity infinity infinity infinity short range short range short range
d 0 ∞ ∞ ∞ 110.01 115.53 110.00
β − − − -0.1220 -0.1816 -0.2566
f 16.48 25.21 33.95 − − −
d 8 28.899 9.423 0.500 33.772 14.498 6.164
d13 6.862 6.862 6.862 1.989 1.787 1.198
d17 2.000 5.572 7.582 2.000 5.572 7.582
d22 7.082 3.510 1.500 7.082 3.510 1.500
d28 4.315 18.275 32.723 4.315 18.275 32.723
BF 18.070 18.065 18.063 18.155 18.254 18.438

[Values corresponding to each conditional expression]
(1) f5 / (-f1) = 3.171
(2) | m12 | /fw=1.723
(3) f5 / f4 = 0.895

6 (a), 6 (b), and 6 (c) show focusing of an object at infinity in the wide-angle end state, the intermediate focal length state, and the telephoto end state of the zoom lens according to the second example, respectively. FIG. 7 is a diagram of various types of aberration of FIG.
7 (a), 7 (b), and 7 (c) show focusing of a short-distance object in the wide-angle end state, intermediate focal length state, and telephoto end state of the zoom lens according to Example 2, respectively. FIG. 7 is a diagram of various types of aberration of FIG.
FIG. 8A, FIG. 8B, and FIG. 8C are meridional laterals during image stabilization in the wide-angle end state, the intermediate focal length state, and the telephoto end state of the zoom lens according to the second example, respectively. It is an aberration diagram.

  As is clear from each aberration diagram, the zoom lens according to Example 2 has various aberrations favorably corrected from the wide-angle end state to the telephoto end state, and has high optical performance even during image stabilization. I understand.

(Third embodiment)
9A, 9B, and 9C are cross-sectional views of the zoom lens according to Example 3 in the wide-angle end state, the intermediate focal length state, and the telephoto end state, respectively.
The arrow below each lens group in FIG. 9A indicates the moving direction of each lens group during zooming from the wide-angle end state to the intermediate focal length state. The arrow below each lens group in FIG. 9B indicates the moving direction of each lens group during zooming from the intermediate focal length state to the telephoto end state.

  As shown in FIG. 9A, in the zoom lens according to the present embodiment, the first lens group G1 having a negative refractive power and the second lens group having a positive refractive power are arranged in this order from the object side along the optical axis. It is composed of a lens group G2, a third lens group G3 having a negative refractive power, a fourth lens group G4 having a positive refractive power, and a fifth lens group G5 having a positive refractive power.

  The first lens group G1 includes, in order from the object side along the optical axis, a negative meniscus lens L11 having a convex surface directed toward the object side, a negative meniscus lens L12 having a convex surface directed toward the object side, a biconcave lens L13, and a biconvex lens. And L14. The negative meniscus lens L11 is an aspherical lens in which the object-side lens surface and the image-side lens surface have an aspherical shape.

The second lens group G2 includes, in order from the object side along the optical axis, a second F lens group G2F having a positive refractive power and a second R lens group G2R having a positive refractive power.
The second F lens group G2F includes, in order from the object side along the optical axis, a cemented lens of a biconvex lens L21 and a negative meniscus lens L22 having a concave surface facing the object side, and a negative meniscus lens L23 having a convex surface facing the object side. It consists of The biconvex lens L21 is an aspherical lens having an aspherical surface on the object side.
The second R lens group G2R is composed of, in order from the object side along the optical axis, a cemented lens of a negative meniscus lens L24 having a convex surface facing the object side, a biconvex lens L25, and a negative meniscus lens L26 having a concave surface facing the object side. Has been done.

  The third lens group G3 is composed of an aperture stop S, a cemented lens of a biconcave lens L31 and a positive meniscus lens L32 having a convex surface directed toward the object side, and a flare cut stop FS in order from the object side along the optical axis. Has been done. The positive meniscus lens L32 is an aspherical lens whose lens surface on the image side has an aspherical shape.

  The fourth lens group G4 includes, in order from the object side along the optical axis, a cemented lens of a biconvex lens L41 and a negative meniscus lens L42 having a concave surface facing the object side, and a negative meniscus lens L43 having a convex surface facing the object side. It is composed of a cemented lens with a positive meniscus lens L44 having a convex surface facing the object side. The negative meniscus lens L42 is an aspherical lens having an aspherical surface on the image side.

  The fifth lens group G5 is composed of a positive meniscus lens L51 having a concave surface facing the object side. The positive meniscus lens L51 is an aspherical lens having an aspherical surface on the object side and the image side.

  On the image plane I, an image pickup device (not shown) composed of CCD, CMOS or the like is arranged.

  With the above-described configuration, in the zoom lens according to the present embodiment, the distance between the first lens group G1 and the second lens group G2 decreases during zooming from the wide-angle end state to the telephoto end state, and the second lens group The distance between the lens group G2 and the third lens group G3 increases, the distance between the third lens group G3 and the fourth lens group G4 decreases, and the distance between the fourth lens group G4 and the fifth lens group G5 increases. As described above, the first lens group G1, the second lens group G2, the third lens group G4, the fourth lens group G4, and the fifth lens group G5 move along the optical axis with respect to the image plane I. Specifically, during zooming, the first lens group G1 once moves to the image plane I side and then to the object side, and the second lens group G2 and the fourth lens group G4 move integrally to the object side. Then, the third lens group G3 moves to the object side, and the fifth lens group G5 once moves to the object side and then moves to the image plane I side.

  The aperture stop S is arranged between the second lens group G2 and the third lens group G3, and moves together with the third lens group G3 during zooming from the wide-angle end state to the telephoto end state.

  Further, in the zoom lens according to the present embodiment, by moving the second F lens group G2F to the image plane I side, focusing from an object at infinity to a near object is performed.

  In the zoom lens according to the present embodiment, a cemented lens of the biconcave lens L31 of the third lens group G3 and the positive meniscus lens L32 having a convex surface facing the object side is used as a vibration-proof lens group and a component in a direction orthogonal to the optical axis. By moving in a direction including, the image plane is corrected when the image blur occurs, that is, the image stabilization is performed.

Here, when the focal length of the entire zoom lens system according to the present embodiment is f and the ratio of the amount of movement of the image on the image plane I to the amount of movement of the image stabilizing lens group during blur correction is K, the angle is In order to correct the rotational shake of θ, it is sufficient to shift the antivibration lens group by (f · tan θ) / K in the direction orthogonal to the optical axis.
In the wide-angle end state, the zoom lens according to the present example has a vibration isolation coefficient K of 0.56 and a focal length of 16.48 (mm) (see Table 3 below), so that 0.81 ° The movement amount of the anti-vibration lens unit for correcting the rotational shake is 0.42 (mm). Further, in the intermediate focal length state, the image stabilization coefficient K is 0.70 and the focal length is 25.21 (mm) (see Table 3 below), so to correct the rotational shake of 0.66 °. The movement amount of the image stabilizing lens unit is 0.41 (mm). In addition, in the telephoto end state, the image stabilization coefficient K is 0.87 and the focal length is 33.95 (mm) (see Table 3 below). Therefore, in order to correct the rotational shake of 0.57 °, The movement amount of the image stabilizing lens unit is 0.39 (mm).

  Table 3 below lists specifications of the zoom lens according to the third example.

(Table 3) Third embodiment [Overall specifications]
W M T
f 16.48 25.21 33.95
FNO 2.83 2.83 2.83
ω 54.0 39.9 31.7
Y 21.64 21.64 21.64
TL 162.369 156.568 162.359
BF 18.069 18.479 18.059

[Surface data]
Surface number rd nd νd
Object ∞
* 1) 73.35843 2.000 1.85135 40.1
* 2) 19.65231 7.423
3) 60.85659 2.000 1.90043 37.4
4) 26.46067 12.865
5) -37.68469 2.000 1.49782 82.6
6) 319.60622 0.150
7) 98.35638 6.315 2.00100 29.1
8) -91.84642 (variable)

* 9) 45.12179 9.169 1.58313 59.4
10) -32.35918 1.500 1.65160 58.6
11) -70.79534 1.426
12) 116.36340 1.500 1.51742 52.2
13) 36.40999 (variable)

14) 27.76490 1.500 1.84500 23.9
15) 21.11208 12.352 1.48749 70.3
16) -40.48676 1.500 1.79173 26.0
17) -63.27082 (variable)

18) (Aperture) ∞ 3.500
19) -209.12746 1.500 1.74400 44.8
20) 27.47317 3.887 1.80244 25.6
* 21) 62.77212 1.000
22) (FS) ∞ (variable)

23) 26.82011 7.501 1.49782 82.6
24) -55.69746 1.500 1.88202 37.2
* 25) -89.72149 0.150
26) 63.20031 1.500 1.90043 37.4
27) 19.07631 7.703 1.49782 82.6
28) 80.36061 (variable)

* 29) -135.00000 5.077 1.77250 49.5
* 30) -44.25947 (BF)
Image plane ∞

[Lens group data]
Starting surface Focal length
G1 1 -26.11
G2 9 40.20
G3 18 -70.00
G4 23 93.63
G5 29 83.21

[Aspherical data]
Surface number: 1
κ = 8.75000E-02
A4 = -2.78056E-06
A6 = 3.66529E-09
A8 = -2.32659E-12
A10 = 7.29739E-16

Surface number: 2
κ = 1.25600E-01
A4 = -1.66529E-06
A6 = 1.18889E-09
A8 = 5.12891E-12
A10 = -1.72885E-16

Surface number: 9
κ = 1.00000E + 00
A4 = -3.12858E-06
A6 = -1.15459E-09
A8 = 5.52871E-12
A10 = -7.23502E-15

Surface number: 21
κ = 1.36390E + 00
A4 = -1.54769E-07
A6 = -2.666171E-08
A8 = 2.07963E-10
A10 = -5.54299E-13

Surface number: 25
κ = 1.00000E + 00
A4 = 1.15286E-05
A6 = 7.02471E-09
A8 = -1.60325E-11
A10 = -9.68792E-14

Surface number: 29
κ = 1.00000E + 00
A4 = 1.12240E-05
A6 = -4.41692E-08
A8 = 1.19461E-10
A10 = -1.22999E-13

Surface number: 30
κ = 1.00000E + 00
A4 = 1.62814E-05
A6 = -5.22346E-08
A8 = 1.25318E-10
A10 = -1.19716E-13

[Variable interval data]
W M T W M T
Infinity infinity infinity infinity short range short range short range
d 0 ∞ ∞ ∞ 110.00 115.79 110.00
β − − − -0.1221 -0.1814 -0.2567
f 16.48 25.21 33.95 − − −
d 8 28.797 9.141 0.500 33.624 14.169 6.113
d13 6.847 6.847 6.847 2.020 1.820 1.234
d17 2.000 5.812 7.792 2.000 5.812 7.792
d22 7.292 3.480 1.500 7.292 3.480 1.500
d28 4.346 17.791 32.643 4.346 17.791 32.643
BF 18.069 18.479 18.059 18.154 18.667 18.434

[Values corresponding to each conditional expression]
(1) f5 / (-f1) = 3.187
(2) | m12 | /fw=1.717
(3) f5 / f4 = 0.889

FIG. 10A, FIG. 10B, and FIG. 10C are respectively for focusing the object at infinity in the wide-angle end state, the intermediate focal length state, and the telephoto end state of the zoom lens according to the third example. FIG. 7 is a diagram of various types of aberration of FIG.
11 (a), 11 (b), and 11 (c) show focusing of a short-distance object in the wide-angle end state, intermediate focal length state, and telephoto end state of the zoom lens according to the third example, respectively. FIG. 7 is a diagram of various types of aberration of FIG.
12 (a), 12 (b), and 12 (c) are the meridional laterals during image stabilization in the wide-angle end state, the intermediate focal length state, and the telephoto end state of the zoom lens according to Example 3, respectively. It is an aberration diagram.

  As is clear from each aberration diagram, the zoom lens according to the third example is satisfactorily corrected for various aberrations from the wide-angle end state to the telephoto end state, and has high optical performance even during image stabilization. I understand.

(Fourth embodiment)
13A, 13B, and 13C are cross-sectional views of the zoom lens according to Example 4 in the wide-angle end state, the intermediate focal length state, and the telephoto end state, respectively.
The arrow below each lens group in FIG. 13A indicates the moving direction of each lens group during zooming from the wide-angle end state to the intermediate focal length state. The arrow below each lens group in FIG. 13B indicates the moving direction of each lens group during zooming from the intermediate focal length state to the telephoto end state.

  As shown in FIG. 13A, in the zoom lens according to the present embodiment, the first lens group G1 having a negative refractive power and the second lens having a positive refractive power are arranged in this order from the object side along the optical axis. It is composed of a lens group G2, a third lens group G3 having a negative refractive power, a fourth lens group G4 having a positive refractive power, and a fifth lens group G5 having a positive refractive power.

  The first lens group G1 includes, in order from the object side along the optical axis, a negative meniscus lens L11 having a convex surface directed toward the object side, a negative meniscus lens L12 having a convex surface directed toward the object side, a biconcave lens L13, and a biconvex lens. And L14. The negative meniscus lens L11 is an aspherical lens in which the object-side lens surface and the image-side lens surface have an aspherical shape.

The second lens group G2 includes, in order from the object side along the optical axis, a second F lens group G2F having a positive refractive power and a second R lens group G2R having a positive refractive power.
The second F lens group G2F includes, in order from the object side along the optical axis, a cemented lens of a biconvex lens L21 and a negative meniscus lens L22 having a concave surface facing the object side, and a negative meniscus lens L23 having a convex surface facing the object side. It consists of The biconvex lens L21 is an aspherical lens having an aspherical surface on the object side.
The second R lens group G2R is composed of, in order from the object side along the optical axis, a cemented lens of a negative meniscus lens L24 having a convex surface facing the object side, a biconvex lens L25, and a negative meniscus lens L26 having a concave surface facing the object side. Has been done.

  The third lens group G3 is composed of an aperture stop S, a cemented lens of a biconcave lens L31 and a positive meniscus lens L32 having a convex surface directed toward the object side, and a flare cut stop FS in order from the object side along the optical axis. Has been done. The positive meniscus lens L32 is an aspherical lens whose lens surface on the image side has an aspherical shape.

  The fourth lens group G4 includes, in order from the object side along the optical axis, a cemented lens of a biconvex lens L41 and a negative meniscus lens L42 having a concave surface facing the object side, and a negative meniscus lens L43 having a convex surface facing the object side. It is composed of a cemented lens with a positive meniscus lens L44 having a convex surface facing the object side. The negative meniscus lens L42 is an aspherical lens having an aspherical surface on the image side.

  The fifth lens group G5 is composed of a positive meniscus lens L51 having a concave surface facing the object side. The positive meniscus lens L51 is an aspherical lens having an aspherical surface on the object side and the image side.

  On the image plane I, an image pickup device (not shown) composed of CCD, CMOS or the like is arranged.

  With the above-described configuration, in the zoom lens according to the present embodiment, the distance between the first lens group G1 and the second lens group G2 decreases during zooming from the wide-angle end state to the telephoto end state, and the second lens group The distance between the lens group G2 and the third lens group G3 increases, the distance between the third lens group G3 and the fourth lens group G4 decreases, and the distance between the fourth lens group G4 and the fifth lens group G5 increases. As described above, the first lens group G1, the second lens group G2, the third lens group G4, and the fourth lens group G4 move along the optical axis with respect to the image plane I. Specifically, during zooming, the first lens group G1 first moves to the image plane I side and then to the object side, and the second lens group G2 and the fourth lens group G4 move integrally to the object side. The third lens group G3 moves toward the object side, and the fifth lens group G5 is fixed with respect to the image plane I.

  The aperture stop S is arranged between the second lens group G2 and the third lens group G3, and moves together with the third lens group G3 during zooming from the wide-angle end state to the telephoto end state.

  Further, in the zoom lens according to the present embodiment, by moving the second F lens group G2F to the image plane I side, focusing from an object at infinity to a near object is performed.

  In the zoom lens according to the present embodiment, a cemented lens of the biconcave lens L31 of the third lens group G3 and the positive meniscus lens L32 having a convex surface facing the object side is used as a vibration-proof lens group and a component in a direction orthogonal to the optical axis. By moving in a direction including, the image plane is corrected when the image blur occurs, that is, the image stabilization is performed.

Here, when the focal length of the entire zoom lens system according to the present embodiment is f and the ratio of the amount of movement of the image on the image plane I to the amount of movement of the image stabilizing lens group during blur correction is K, the angle is In order to correct the rotational shake of θ, it is sufficient to shift the antivibration lens group by (f · tan θ) / K in the direction orthogonal to the optical axis.
In the wide-angle end state, the zoom lens according to the present example has an image stabilization coefficient K of 0.81 and a focal length of 18.54 (mm) (see Table 4 below), so 0.77 ° The movement amount of the anti-vibration lens unit for correcting the rotational shake is 0.30 (mm). Further, in the intermediate focal length state, the image stabilization coefficient K is 1.00 and the focal length is 25.21 (mm) (see Table 4 below), so to correct the rotational shake of 0.66 °. The movement amount of the image stabilizing lens unit is 0.29 (mm). Further, in the telephoto end state, the image stabilization coefficient K is 1.26 and the focal length is 33.95 (mm) (see Table 4 below), so that the correction of rotational shake of 0.57 ° is performed. The movement amount of the image stabilizing lens unit is 0.27 (mm).

  Table 4 below lists specifications of the zoom lens according to Example 4.

(Table 4) Fourth embodiment [Overall specifications]
W M T
f 18.54 25.21 33.95
FNO 2.83 2.83 2.83
ω 49.9 40.1 31.7
Y 21.64 21.64 21.64
TL 160.545 157.622 162.364
BF 18.069 18.074 18.064

[Surface data]
Surface number rd nd νd
Object ∞
* 1) 64.13853 2.000 1.82080 42.7
* 2) 20.5 2237 7.450
3) 42.79628 2.000 1.84300 37.4
4) 23.01367 14.005
5) -42.12649 2.000 1.49782 82.6
6) 60.80104 0.150
7) 55.48158 6.486 2.00100 29.1
8) -197.93506 (variable)

* 9) 46.12318 12.702 1.58313 59.4
10) -26.66064 1.500 1.61772 49.8
11) -71.59323 0.150
12) 68.72530 1.500 1.51742 52.2
13) 35.19343 (variable)

14) 27.39712 1.500 1.84666 23.8
15) 20.26274 11.974 1.48749 70.3
16) -34.96195 1.500 1.80000 25.6
17) -55.58525 (variable)

18) (Aperture) ∞ 4.000
19) -144.55027 1.500 1.74400 44.8
20) 20.23731 4.012 1.80244 25.6
* 21) 40.54944 1.000
22) (FS) ∞ (variable)

23) 29.62933 6.997 1.49782 82.6
24) -75.50908 1.500 1.88202 37.2
* 25) -112.41227 0.150
26) 34.10106 1.500 1.90043 37.4
27) 19.08383 7.811 1.49782 82.6
28) 56.03390 (variable)

* 29) -135.00000 4.569 1.77250 49.5
* 30) -51.50452 (BF)
Image plane ∞

[Lens group data]
Starting surface Focal length
G1 1 -26.00
G2 9 38.17
G3 18 -45.00
G4 23 54.97
G5 29 105.29

[Aspherical data]
Surface number: 1
κ = 1.97190E + 00
A4 = -3.80899E-06
A6 = 3.65826E-09
A8 = -2.38771E-12
A10 = 7.43869E-16

Surface number: 2
κ = 8.82000E-02
A4 = -1.21936E-06
A6 = 2.60285E-09
A8 = 9.42881E-13
A10 = 3.22230E-15

Surface number: 9
κ = 1.00000E + 00
A4 = -3.225645E-06
A6 = 5.35394E-10
A8 = 0.00000E + 00
A10 = 0.00000E + 00

Surface number: 21
κ = 4.59700E-01
A4 = -1.02727E-06
A6 = -1.01707E-08
A8 = 9.24484E-11
A10 = -2.40570E-13

Surface number: 25
κ = 1.00000E + 00
A4 = 9.28617E-06
A6 = 1.98222E-09
A8 = 3.47233E-11
A10 = -1.62414E-13

Surface number: 29
κ = 1.00000E + 00
A4 = 8.29178E-06
A6 = -3.50865E-08
A8 = 1.26307E-10
A10 = -1.60070E-13

Surface number: 30
κ = 1.00000E + 00
A4 = 1.30379E-05
A6 = -4.40208E-08
A8 = 1.33306E-10
A10 = -1.56261E-13

[Variable interval data]
W M T W M T
Infinity infinity infinity infinity short range short range short range
d 0 ∞ ∞ ∞ 111.82 114.75 110.00
β − − − -0.1327 -0.1788 -0.2514
f 18.54 25.21 33.95 − − −
d 8 22.618 9.438 0.500 27.248 14.104 5.591
d13 8.395 8.395 8.395 3.766 3.729 3.304
d17 3.500 5.288 6.734 3.500 5.288 6.734
d22 4.734 2.946 1.500 4.734 2.946 1.500
d28 5.273 15.525 29.215 5.273 15.525 29.215
BF 18.069 18.074 18.064 18.169 18.256 18.424

[Values corresponding to each conditional expression]
(1) f5 / (-f1) = 4.050
(2) | m12 | /fw=1.193
(3) f5 / f4 = 1.915

14 (a), 14 (b), and 14 (c) show focusing of an object at infinity in the wide-angle end state, intermediate focal length state, and telephoto end state of the zoom lens according to Example 4, respectively. FIG. 7 is a diagram of various types of aberration of FIG.
15 (a), 15 (b), and 15 (c) show focusing of a short-distance object in the wide-angle end state, intermediate focal length state, and telephoto end state of the zoom lens according to Example 4, respectively. FIG. 7 is a diagram of various types of aberration of FIG.
16 (a), 16 (b), and 16 (c) are the meridional laterals during image stabilization in the wide-angle end state, intermediate focal length state, and telephoto end state of the zoom lens according to Example 4, respectively. It is an aberration diagram.

  As is clear from each aberration diagram, the zoom lens according to Example 4 is properly corrected for various aberrations from the wide-angle end state to the telephoto end state, and has high optical performance even during vibration isolation. I understand.

(Fifth embodiment)
17A, 17B, and 17C are cross-sectional views of the zoom lens according to the fifth example in a wide-angle end state, an intermediate focal length state, and a telephoto end state, respectively.
The arrow below each lens group in FIG. 17A indicates the moving direction of each lens group during zooming from the wide-angle end state to the intermediate focal length state. The arrow below each lens group in FIG. 17B indicates the moving direction of each lens group during zooming from the intermediate focal length state to the telephoto end state.

  As shown in FIG. 17A, in the zoom lens according to the present embodiment, the first lens group G1 having a negative refractive power and the second lens having a positive refractive power are sequentially arranged from the object side along the optical axis. It is composed of a lens group G2, a third lens group G3 having a negative refractive power, a fourth lens group G4 having a positive refractive power, and a fifth lens group G5 having a positive refractive power.

  The first lens group G1 includes, in order from the object side along the optical axis, a negative meniscus lens L11 having a convex surface facing the object side, a negative meniscus lens L12 having a convex surface facing the object side, a biconcave lens L13, and a biconvex lens. And L14. The negative meniscus lens L11 is an aspherical lens in which the object-side lens surface and the image-side lens surface have an aspherical shape.

The second lens group G2 includes, in order from the object side along the optical axis, a second F lens group G2F having a positive refractive power and a second R lens group G2R having a positive refractive power.
The second F lens group G2F includes, in order from the object side along the optical axis, a cemented lens of a biconvex lens L21 and a negative meniscus lens L22 having a concave surface facing the object side, and a negative meniscus lens L23 having a convex surface facing the object side. It consists of The biconvex lens L21 is an aspherical lens having an aspherical surface on the object side.
The second R lens group G2R is composed of, in order from the object side along the optical axis, a cemented lens of a negative meniscus lens L24 having a convex surface facing the object side, a biconvex lens L25, and a negative meniscus lens L26 having a concave surface facing the object side. Has been done.

  The third lens group G3 is composed of an aperture stop S, a cemented lens of a biconcave lens L31 and a positive meniscus lens L32 having a convex surface directed toward the object side, and a flare cut stop FS in order from the object side along the optical axis. Has been done. The positive meniscus lens L32 is an aspherical lens whose lens surface on the image side has an aspherical shape.

  The fourth lens group G4 includes, in order from the object side along the optical axis, a cemented lens of a biconvex lens L41 and a negative meniscus lens L42 having a concave surface facing the object side, and a negative meniscus lens L43 having a convex surface facing the object side. It is composed of a cemented lens with a positive meniscus lens L44 having a convex surface facing the object side. The negative meniscus lens L42 is an aspherical lens having an aspherical surface on the image side.

  The fifth lens group G5 is composed of a positive meniscus lens L51 having a concave surface facing the object side. The positive meniscus lens L51 is an aspherical lens having an aspherical surface on the object side and the image side.

  On the image plane I, an image pickup device (not shown) composed of CCD, CMOS or the like is arranged.

  With the above-described configuration, in the zoom lens according to the present embodiment, the distance between the first lens group G1 and the second lens group G2 decreases during zooming from the wide-angle end state to the telephoto end state, and the second lens group The distance between the lens group G2 and the third lens group G3 increases, the distance between the third lens group G3 and the fourth lens group G4 decreases, and the distance between the fourth lens group G4 and the fifth lens group G5 increases. As described above, the first lens group G1, the second lens group G2, the third lens group G4, and the fourth lens group G4 move along the optical axis with respect to the image plane I. Specifically, during zooming, the first lens group G1 once moves to the image plane I side and then to the object side, and the second lens group G2 and the fourth lens group G4 move integrally to the object side. The third lens group G3 moves toward the object side, and the fifth lens group G5 is fixed with respect to the image plane I.

  The aperture stop S is arranged between the second lens group G2 and the third lens group G3, and moves together with the third lens group G3 during zooming from the wide-angle end state to the telephoto end state.

  Further, in the zoom lens according to the present embodiment, by moving the second F lens group G2F to the image plane I side, focusing from an object at infinity to a near object is performed.

  In the zoom lens according to the present embodiment, a cemented lens of the biconcave lens L31 of the third lens group G3 and the positive meniscus lens L32 having a convex surface facing the object side is used as a vibration-proof lens group and a component in a direction orthogonal to the optical axis. By moving in a direction including, the image plane is corrected when the image blur occurs, that is, the image stabilization is performed.

Here, when the focal length of the entire zoom lens system according to the present embodiment is f and the ratio of the amount of movement of the image on the image plane I to the amount of movement of the image stabilizing lens group during blur correction is K, the angle is In order to correct the rotational shake of θ, it is sufficient to shift the antivibration lens group by (f · tan θ) / K in the direction orthogonal to the optical axis.
In the wide-angle end state, the zoom lens according to the present example has an image stabilization coefficient K of 0.47 and a focal length of 15.45 (mm) (see Table 5 below), so that 0.84 ° is obtained. The movement amount of the anti-vibration lens unit for correcting the rotational shake is 0.48 (mm). Further, in the intermediate focal length state, the image stabilization coefficient K is 0.61 and the focal length is 25.21 (mm) (see Table 5 below), so to correct the rotational blur of 0.66 °. The movement amount of the image stabilizing lens unit is 0.48 (mm). In addition, in the telephoto end state, the image stabilization coefficient K is 0.76 and the focal length is 33.95 (mm) (see Table 5 below). Therefore, in order to correct the rotational shake of 0.57 °, The movement amount of the image stabilizing lens unit is 0.44 (mm).

  Table 5 below lists specifications of the zoom lens according to the fifth example.

(Table 5) Fifth Example [Overall Specifications]
W M T
f 15.45 25.21 33.95
FNO 2.83 2.83 2.83
ω 56.2 40.0 31.8
Y 21.64 21.64 21.64
TL 168.787 161.395 167.660
BF 18.067 18.070 18.058

[Surface data]
Surface number rd nd νd
Object ∞
* 1) 84.32721 2.000 1.82080 42.7
* 2) 22.42250 6.533
3) 40.43903 2.000 1.90043 37.4
4) 22.79897 18.443
5) -36.72174 2.000 1.49782 82.6
6) 108.66132 0.150
7) 86.07473 6.091 2.00100 29.1
8) -113.52466 (variable)

* 9) 56.20536 8.334 1.58313 59.4
10) -34.82724 1.500 1.62896 51.8
11) -62.67282 0.150
12) 1521.91690 1.500 1.51742 52.2
13) 63.48881 (variable)

14) 32.18721 1.500 1.83207 24.9
15) 23.97842 11.952 1.48749 70.3
16) -42.36534 1.500 1.79889 25.4
17) -64.06791 (variable)

18) (Aperture) ∞ 4.000
19) -402.90754 1.500 1.74400 44.8
20) 29.51707 4.016 1.80244 25.6
* 21) 67.51202 1.000
22) (FS) ∞ (variable)

23) 30.01453 8.025 1.49782 82.6
24) -48.32228 1.500 1.88202 37.2
* 25) -80.74589 0.150
26) 73.99805 1.500 1.90043 37.4
27) 19.28578 8.991 1.49782 82.6
28) 131.61654 (variable)

* 29) -135.00000 5.020 1.77250 49.5
* 30) -45.90440 (BF)
Image plane ∞

[Lens group data]
Starting surface Focal length
G1 1 -26.00
G2 9 40.61
G3 18 -85.00
G4 23 113.40
G5 29 87.88

[Aspherical data]
Surface number: 1
κ = 1.07450E + 00
A4 = -1.57852E-06
A6 = 2.55869E-09
A8 = -1.24755E-12
A10 = 2.99043E-16

Surface number: 2
κ = 2.82500E-01
A4 = -5.25879E-06
A6 = 2.99379E-09
A8 = -1.07006E-13
A10 = 2.38338E-15

Surface number: 9
κ = 1.00000E + 00
A4 = -3.44380E-06
A6 = 6.36234E-10
A8 = 0.00000E + 00
A10 = 0.00000E + 00

Surface number: 21
κ = 5.97700E-01
A4 = -1.14555E-08
A6 = -6.90561E-09
A8 = 2.24606E-11
A10 = -2.11799E-15

Surface number: 25
κ = 1.00000E + 00
A4 = 8.46457E-06
A6 = -1.83245E-09
A8 = 1.13124E-11
A10 = -6.67256E-14

Surface number: 29
κ = 1.00000E + 00
A4 = 1.35371E-05
A6 = -4.85133E-08
A8 = 1.04081E-10
A10 = -9.31604E-14

Surface number: 30
κ = 1.00000E + 00
A4 = 2.00382E-05
A6 = -5.78531E-08
A8 = 1.07159E-10
A10 = -8.91147E-14

[Variable interval data]
W M T W M T
Infinity Infinity Infinity Infinity Near Distance Near Distance Near
d 0 ∞ ∞ ∞ 103.58 110.97 104.70
β − − − -0.1177 -0.1847 -0.2625
f 15.45 25.21 33.95 − − −
d 8 32.660 9.394 0.500 37.602 14.284 5.903
d13 6.126 6.126 6.126 1.184 1.237 0.724
d17 1.500 5.658 7.190 1.500 5.658 7.190
d22 7.190 3.032 1.500 7.190 3.032 1.500
d28 3.889 19.760 34.930 3.889 19.760 34.930
BF 18.067 18.070 18.058 18.146 18.265 18.451

[Values corresponding to each conditional expression]
(1) f5 / (-f1) = 3.380
(2) | m12 | /fw=2.082
(3) f5 / f4 = 0.775

18 (a), 18 (b), and 18 (c) show focusing of an object at infinity in the wide-angle end state, intermediate focal length state, and telephoto end state of the zoom lens according to Example 5, respectively. FIG. 7 is a diagram of various types of aberration of FIG.
19 (a), 19 (b), and 19 (c) show focusing of a short-distance object in the wide-angle end state, intermediate focal length state, and telephoto end state of the zoom lens according to Example 5, respectively. FIG. 7 is a diagram of various types of aberration of FIG.
20 (a), 20 (b), and 20 (c) are the meridional laterals during image stabilization in the wide-angle end state, intermediate focal length state, and telephoto end state of the zoom lens according to Example 5, respectively. It is an aberration diagram.

  As is apparent from each aberration diagram, the zoom lens according to Example 5 has various aberrations favorably corrected from the wide-angle end state to the telephoto end state, and has high optical performance even during vibration isolation. I understand.

(Sixth embodiment)
21 (a), 21 (b), and 21 (c) are cross-sectional views of the zoom lens according to Example 6 in the wide-angle end state, the intermediate focal length state, and the telephoto end state, respectively.
The arrow below each lens group in FIG. 21A indicates the moving direction of each lens group during zooming from the wide-angle end state to the intermediate focal length state. The arrow below each lens group in FIG. 21B indicates the moving direction of each lens group during zooming from the intermediate focal length state to the telephoto end state.

  As shown in FIG. 21A, in the zoom lens according to the present embodiment, the first lens group G1 having a negative refractive power and the second lens having a positive refractive power are arranged in this order from the object side along the optical axis. It is composed of a lens group G2, a third lens group G3 having a negative refractive power, a fourth lens group G4 having a positive refractive power, and a fifth lens group G5 having a positive refractive power.

  The first lens group G1 includes, in order from the object side along the optical axis, a negative meniscus lens L11 having a convex surface facing the object side, a negative meniscus lens L12 having a convex surface facing the object side, a biconcave lens L13, and a biconvex lens. And L14. The negative meniscus lens L11 is an aspherical lens in which the object-side lens surface and the image-side lens surface have an aspherical shape. The negative meniscus lens L12 is an aspherical lens having an aspherical surface on the image side.

The second lens group G2 includes, in order from the object side along the optical axis, a second F lens group G2F having a positive refractive power and a second R lens group G2R having a positive refractive power.
The second F lens group G2F is composed of, in order from the object side along the optical axis, a cemented lens of a biconvex lens L21 and a negative meniscus lens L22 having a concave surface facing the object side, and a biconcave lens L23. The biconvex lens L21 is an aspherical lens having an aspherical surface on the object side.
The second R lens group G2R is composed of, in order from the object side along the optical axis, a cemented lens of a negative meniscus lens L24 having a convex surface facing the object side, a biconvex lens L25, and a negative meniscus lens L26 having a concave surface facing the object side. Has been done. The negative meniscus lens L24 is an aspherical lens having an aspherical surface on the object side.

  The third lens group G3 is composed of an aperture stop S, a cemented lens of a biconcave lens L31 and a positive meniscus lens L32 having a convex surface directed toward the object side, and a flare cut stop FS in order from the object side along the optical axis. Has been done.

  The fourth lens group G4 includes, in order from the object side along the optical axis, a cemented lens of a biconvex lens L41 and a negative meniscus lens L42 having a concave surface facing the object side, and a negative meniscus lens L43 having a convex surface facing the object side. It is composed of a cemented lens with a positive meniscus lens L44 having a convex surface facing the object side. The negative meniscus lens L42 is an aspherical lens having an aspherical surface on the image side.

  The fifth lens group G5 is composed of a positive meniscus lens L51 having a concave surface facing the object side. The positive meniscus lens L51 is an aspherical lens having an aspherical surface on the object side and the image side.

  On the image plane I, an image pickup device (not shown) composed of CCD, CMOS or the like is arranged.

  With the above-described configuration, in the zoom lens according to the present embodiment, the distance between the first lens group G1 and the second lens group G2 decreases during zooming from the wide-angle end state to the telephoto end state, and the second lens group The distance between the lens group G2 and the third lens group G3 increases, the distance between the third lens group G3 and the fourth lens group G4 decreases, and the distance between the fourth lens group G4 and the fifth lens group G5 increases. As described above, the first lens group G1, the second lens group G2, the third lens group G4, and the fourth lens group G4 move along the optical axis with respect to the image plane I. Specifically, during zooming, the first lens group G1 once moves to the image plane I side and then to the object side, and the second lens group G2 and the fourth lens group G4 move integrally to the object side. The third lens group G3 moves toward the object side, and the fifth lens group G5 is fixed with respect to the image plane I.

  The aperture stop S is arranged between the second lens group G2 and the third lens group G3, and moves together with the third lens group G3 during zooming from the wide-angle end state to the telephoto end state.

  Further, in the zoom lens according to the present embodiment, by moving the second F lens group G2F to the image plane I side, focusing from an object at infinity to a near object is performed.

  Further, in the zoom lens according to the present embodiment, the second R lens group G2R is moved in the direction including the component in the direction orthogonal to the optical axis as the image stabilization lens group to correct the image surface when an image blur occurs, that is, to perform image stabilization. It is carried out.

Here, when the focal length of the entire zoom lens system according to the present embodiment is f and the ratio of the amount of movement of the image on the image plane I to the amount of movement of the image stabilizing lens group during blur correction is K, the angle is In order to correct the rotational shake of θ, it is sufficient to shift the antivibration lens group by (f · tan θ) / K in the direction orthogonal to the optical axis.
In the wide-angle end state, the zoom lens according to the present example has a vibration isolation coefficient K of 1.07 and a focal length of 16.48 (mm) (see Table 6 below), so 0.81 ° is set. The movement amount of the anti-vibration lens group for correcting the rotational shake is 0.22 (mm). Further, in the intermediate focal length state, the image stabilization coefficient K is 1.37 and the focal length is 25.21 (mm) (see Table 6 below), so to correct the rotational shake of 0.66 °. The movement amount of the image stabilizing lens group is 0.21 (mm). Further, in the telephoto end state, the image stabilization coefficient K is 1.67 and the focal length is 33.95 (mm) (see Table 6 below), so that the rotational shake of 0.57 ° is corrected. The movement amount of the image stabilizing lens unit is 0.20 (mm).

  Table 6 below lists specifications of the zoom lens according to Example 6.

(Table 6) Sixth Example [Overall Specifications]
W M T
f 16.48 25.21 33.95
FNO 4.00 4.00 4.00
ω 54.1 39.8 31.7
Y 21.64 21.64 21.64
TL 162.369 156.678 160.978
BF 18.069 18.064 18.074

[Surface data]
Surface number rd nd νd
Object ∞
* 1) 180.13769 2.000 1.82080 42.7
* 2) 19.96088 6.970
3) 94.52854 2.000 1.90043 37.4
* 4) 28.44278 9.857
5) -42.62350 2.000 1.49782 82.6
6) 244.08326 0.150
7) 61.25466 5.605 2.00100 29.1
8) -150.06559 (variable)

* 9) 36.24721 7.764 1.58313 59.4
10) -22.60689 1.500 1.65844 50.8
11) -43.72965 0.151
12) -207.94715 1.500 1.51742 52.2
13) 40.03120 (variable)

* 14) 43.25649 1.500 1.79504 28.7
15) 26.23995 11.085 1.48749 70.3
16) -21.42752 1.500 1.68893 31.2
17) -29.56586 (variable)

18) (Aperture) ∞ 4.000
19) -74.75529 1.500 1.74400 44.8
20) 22.57348 3.362 1.80244 25.6
21) 84.92681 1.000
22) (FS) ∞ (variable)

23) 34.18409 11.631 1.49782 82.6
24) -22.09869 1.500 1.88202 37.2
* 25) -35.01463 0.150
26) 64.77675 1.500 1.90043 37.4
27) 18.18435 8.523 1.49782 82.6
28) 70.17847 (variable)

* 29) -135.00000 5.121 1.77250 49.5
* 30) -46.54146 (BF)
Image plane ∞

[Lens group data]
Starting surface Focal length
G1 1 -23.15
G2 9 37.14
G3 18 -58.82
G4 23 86.56
G5 29 89.68

[Aspherical data]
Surface number: 1
κ = 2.00000E + 00
A4 = 7.91245E-06
A6 = -3.69643E-09
A8 = 1.11415E-12
A10 = -2.04281E-16

Surface number: 2
κ = 1.05500E-01
A4 = -1.07575E-05
A6 = 4.04887E-08
A8 = -2.80099E-11
A10 = 8.02396E-14

Surface number: 4
κ = 1.00000E + 00
A4 = 2.14895E-05
A6 = 5.07570E-09
A8 = -8.70469E-11
A10 = 9.89182E-14

Surface number: 9
κ = 1.00000E + 00
A4 = -5.58940E-06
A6 = -6.24739E-09
A8 = 0.00000E + 00
A10 = 0.00000E + 00

Surface number: 14
κ = 1.00000E + 00
A4 = -4.10738E-06
A6 = 2.26991E-09
A8 = -1.27958E-11
A10 = 2.28497E-14

Surface number: 25
κ = 1.00000E + 00
A4 = 6.63910E-06
A6 = -2.70332E-09
A8 = -1.14938E-11
A10 = -3.86980E-14

Surface number: 29
κ = 1.00000E + 00
A4 = 2.96724E-06
A6 = -7.37447E-10
A8 = 4.28602E-11
A10 = -7.07831E-14

Surface number: 30
κ = 1.00000E + 00
A4 = 5.46618E-06
A6 = -9.05640E-09
A8 = 6.16567E-11
A10 = -8.57111E-14

[Variable interval data]
W M T W M T
Infinity infinity infinity infinity short range short range short range
d 0 ∞ ∞ ∞ 110.00 115.69 111.40
β − − − -0.1243 -0.1848 -0.2589
f 16.48 25.21 33.95 − − −
d 8 27.344 8.875 0.500 31.204 12.826 4.873
d13 7.541 7.541 7.541 3.681 3.590 3.168
d17 2.000 7.319 11.342 2.000 7.319 11.342
d22 10.842 5.524 1.500 10.842 5.524 1.500
d28 4.704 17.488 30.153 4.704 17.488 30.158
BF 18.069 18.064 18.074 18.157 18.259 18.456

[Values corresponding to each conditional expression]
(1) f5 / (-f1) = 3.873
(2) | m12 | /fw=1.629
(3) f5 / f4 = 1.036

22 (a), 22 (b), and 22 (c) show focusing of an object at infinity in the wide-angle end state, intermediate focal length state, and telephoto end state of the zoom lens according to Example 6, respectively. FIG. 7 is a diagram of various types of aberration of FIG.
23 (a), 23 (b), and 23 (c) show focusing of a short-distance object in the wide-angle end state, intermediate focal length state, and telephoto end state of the zoom lens according to Example 6, respectively. FIG. 7 is a diagram of various types of aberration of FIG.
24 (a), 24 (b), and 24 (c) are the meridional laterals during image stabilization in the wide-angle end state, the intermediate focal length state, and the telephoto end state of the zoom lens according to Example 6, respectively. It is an aberration diagram.

  As is clear from each aberration diagram, the zoom lens according to Example 6 has various aberrations favorably corrected from the wide-angle end state to the telephoto end state, and has high optical performance even during image stabilization. I understand.

(Seventh embodiment)
25 (a), 25 (b), and 25 (c) are cross-sectional views of the zoom lens according to Example 7 in the wide-angle end state, the intermediate focal length state, and the telephoto end state, respectively.
The arrow below each lens group in FIG. 25A indicates the moving direction of each lens group during zooming from the wide-angle end state to the intermediate focal length state. The arrow below each lens group in FIG. 25B indicates the moving direction of each lens group during zooming from the intermediate focal length state to the telephoto end state.

  As shown in FIG. 25A, in the zoom lens according to the present example, the first lens group G1 having a negative refractive power and the second lens group having a positive refractive power are sequentially arranged from the object side along the optical axis. It is composed of a lens group G2, a third lens group G3 having a negative refractive power, a fourth lens group G4 having a positive refractive power, and a fifth lens group G5 having a positive refractive power.

  The first lens group G1 has, in order from the object side along the optical axis, a negative meniscus lens L11 having a convex surface directed to the object side, a negative meniscus lens L12 having a convex surface directed to the object side, and a concave surface directed to the object side. It is composed of a negative meniscus lens L13 and a biconvex lens L14. The negative meniscus lens L11 is an aspherical lens in which the object-side lens surface and the image-side lens surface have an aspherical shape.

The second lens group G2 includes, in order from the object side along the optical axis, a second F lens group G2F having a positive refractive power and a second R lens group G2R having a positive refractive power.
The second F lens group G2F includes, in order from the object side along the optical axis, a cemented lens of a biconvex lens L21 and a negative meniscus lens L22 having a concave surface facing the object side, and a negative meniscus lens L23 having a convex surface facing the object side. It consists of The biconvex lens L21 is an aspherical lens having an aspherical surface on the object side.
The second R lens group G2R is composed of, in order from the object side along the optical axis, a cemented lens of a negative meniscus lens L24 having a convex surface facing the object side, a biconvex lens L25, and a negative meniscus lens L26 having a concave surface facing the object side. Has been done.

  The third lens group G3 is composed of an aperture stop S, a cemented lens of a biconcave lens L31 and a positive meniscus lens L32 having a convex surface directed toward the object side, and a flare cut stop FS in order from the object side along the optical axis. Has been done. The positive meniscus lens L32 is an aspherical lens whose lens surface on the image side has an aspherical shape.

  The fourth lens group G4 includes, in order from the object side along the optical axis, a cemented lens of a biconvex lens L41 and a negative meniscus lens L42 having a concave surface facing the object side, and a negative meniscus lens L43 having a convex surface facing the object side. It is composed of a cemented lens with a positive meniscus lens L44 having a convex surface facing the object side. The negative meniscus lens L42 is an aspherical lens having an aspherical surface on the image side.

  The fifth lens group G5 is composed of a positive meniscus lens L51 having a concave surface facing the object side. The positive meniscus lens L51 is an aspherical lens having an aspherical surface on the object side and the image side.

  On the image plane I, an image pickup device (not shown) composed of CCD, CMOS or the like is arranged.

  With the above-described configuration, in the zoom lens according to the present embodiment, the distance between the first lens group G1 and the second lens group G2 decreases during zooming from the wide-angle end state to the telephoto end state, and the second lens group The distance between the lens group G2 and the third lens group G3 increases, the distance between the third lens group G3 and the fourth lens group G4 decreases, and the distance between the fourth lens group G4 and the fifth lens group G5 increases. As described above, the first lens group G1, the second lens group G2, the third lens group G4, and the fourth lens group G4 move along the optical axis with respect to the image plane I. Specifically, during zooming, the first lens group G1 once moves to the image plane I side and then to the object side, and the second lens group G2 and the fourth lens group G4 move integrally to the object side. The third lens group G3 moves toward the object side, and the fifth lens group G5 is fixed with respect to the image plane I.

  The aperture stop S is arranged between the second lens group G2 and the third lens group G3, and moves together with the third lens group G3 during zooming from the wide-angle end state to the telephoto end state.

  Further, in the zoom lens according to the present embodiment, by moving the second F lens group G2F to the image plane I side, focusing from an object at infinity to a near object is performed.

  In the zoom lens according to the present embodiment, a cemented lens of the biconcave lens L31 of the third lens group G3 and the positive meniscus lens L32 having a convex surface facing the object side is used as a vibration-proof lens group and a component in a direction orthogonal to the optical axis. By moving in a direction including, the image plane is corrected when the image blur occurs, that is, the image stabilization is performed.

Here, when the focal length of the entire zoom lens system according to the present embodiment is f and the ratio of the amount of movement of the image on the image plane I to the amount of movement of the image stabilizing lens group during blur correction is K, the angle is In order to correct the rotational shake of θ, it is sufficient to shift the antivibration lens group by (f · tan θ) / K in the direction orthogonal to the optical axis.
In the wide-angle end state, the zoom lens according to the present example has an image stabilization coefficient K of 0.56 and a focal length of 16.48 (mm) (see Table 7 below), so that 0.81 ° is set. The movement amount of the anti-vibration lens unit for correcting the rotational shake is 0.42 (mm). Further, in the intermediate focal length state, the image stabilization coefficient K is 0.70 and the focal length is 25.21 (mm) (see Table 7 below), so to correct the rotational shake of 0.66 °. The movement amount of the image stabilizing lens unit is 0.41 (mm). In addition, in the telephoto end state, the image stabilization coefficient K is 0.87 and the focal length is 33.95 (mm) (see Table 7 below). Therefore, in order to correct the rotational shake of 0.57 °, The movement amount of the image stabilizing lens unit is 0.39 (mm).

  Table 7 below lists specifications of the zoom lens according to the seventh example.

(Table 7) Seventh Example [Overall Specifications]
W M T
f 16.48 25.21 33.95
FNO 4.00 4.00 4.00
ω 54.0 39.8 31.8
Y 21.64 21.64 21.64
TL 152.197 148.076 154.253
BF 18.060 18.054 18.063

[Surface data]
Surface number rd nd νd
Object ∞
* 1) 89.63662 2.000 1.82080 42.7
* 2) 19.03463 6.400
3) 59.00594 2.000 1.90043 37.4
4) 25.04291 12.879
5) -34.42001 2.000 1.49782 82.6
6) -220.10809 0.150
7) 110.12188 5.234 2.00100 29.1
8) -94.03704 (variable)

* 9) 34.70954 8.195 1.58313 59.4
10) -22.32702 1.500 1.64013 58.3
11) -56.97811 0.150
12) 143.57014 1.500 1.51742 52.2
13) 29.47978 (variable)

14) 25.69484 1.500 1.79504 28.7
15) 18.31640 7.768 1.48749 70.3
16) -37.27717 1.500 1.73708 28.4
17) -69.75583 (variable)

18) (Aperture) ∞ 4.000
19) -172.99604 1.500 1.74400 44.8
20) 25.25276 3.145 1.80244 25.6
* 21) 65.66381 1.000
22) (FS) ∞ (variable)

23) 28.13736 7.994 1.49782 82.6
24) -39.84408 1.500 1.88202 37.2
* 25) -55.75469 0.150
26) 79.86144 1.500 1.90043 37.4
27) 18.03173 8.303 1.49782 82.6
28) 109.39627 (variable)

* 29) -135.00000 5.201 1.77250 49.5
* 30) -43.87168 (BF)
Image plane ∞

[Lens group data]
Starting surface Focal length
G1 1 -25.31
G2 9 38.11
G3 18 -70.00
G4 23 97.42
G5 29 82.09

[Aspherical data]
Surface number: 1
κ = 0.00000E + 00
A4 = -1.65798E-06
A6 = 2.891887E-09
A8 = -2.10545E-12
A10 = 1.01969E-15

Surface number: 2
κ = 1.52100E-01
A4 = -3.98735E-06
A6 = 1.20818E-08
A8 = -2.50960E-11
A10 = 4.32957E-14

Surface number: 9
κ = 1.00000E + 00
A4 = -5.15908E-06
A6 = 1.64281E-09
A8 = 0.00000E + 00
A10 = 0.00000E + 00

Surface number: 21
κ = 1.89270E + 00
A4 = -3.35320E-07
A6 = -5.17749E-08
A8 = 8.91765E-10
A10 = -5.73216E-12

Surface number: 25
κ = 1.00000E + 00
A4 = 1.10647E-05
A6 = 2.12638E-08
A8 = -1.45298E-10
A10 = 1.80548E-13

Surface number: 29
κ = 1.00000E + 00
A4 = 9.54720E-06
A6 = -3.28939E-08
A8 = 9.31216E-11
A10 = -9.94866E-14

Surface number: 30
κ = 1.00000E + 00
A4 = 1.57892E-05
A6 = -4.68421E-08
A8 = 1.10504E-10
A10 = -1.06766E-13

[Variable interval data]
W M T W M T
Infinity infinity infinity infinity short range short range short range
d 0 ∞ ∞ ∞ 120.16 124.28 118.11
β − − − -0.1141 -0.1719 -0.2434
f 16.48 25.21 33.95 − − −
d 8 26.758 8.756 0.500 31.009 13.089 5.283
d13 7.532 7.532 7.532 3.280 3.198 2.749
d17 2.000 5.495 7.430 2.000 5.495 7.430
d22 6.930 3.434 1.500 6.930 3.434 1.500
d28 3.850 17.737 32.161 3.850 17.737 32.161
BF 18.060 18.054 18.063 18.135 18.223 18.401

[Values corresponding to each conditional expression]
(1) f5 / (-f1) = 3.244
(2) | m12 | /fw=1.593
(3) f5 / f4 = 0.843

26 (a), 26 (b), and 26 (c) show focusing of an object at infinity in the wide-angle end state, intermediate focal length state, and telephoto end state of the zoom lens according to Example 7, respectively. FIG. 7 is a diagram of various types of aberration of FIG.
27 (a), 27 (b), and 27 (c) show focusing of a short-distance object in the wide-angle end state, intermediate focal length state, and telephoto end state of the zoom lens according to Example 7, respectively. FIG. 7 is a diagram of various types of aberration of FIG.
28 (a), 28 (b), and 28 (c) are the meridional laterals during image stabilization in the wide-angle end state, the intermediate focal length state, and the telephoto end state of the zoom lens according to Example 7, respectively. It is an aberration diagram.

  As is clear from each aberration diagram, the zoom lens according to Example 7 is properly corrected for various aberrations from the wide-angle end state to the telephoto end state, and has high optical performance even during vibration isolation. I understand.

(Eighth Example)
29A, 29B, and 29C are cross-sectional views of the zoom lens according to Example 8 in the wide-angle end state, the intermediate focal length state, and the telephoto end state, respectively.
The arrow below each lens group in FIG. 29A indicates the moving direction of each lens group during zooming from the wide-angle end state to the intermediate focal length state. The arrow below each lens group in FIG. 29B indicates the moving direction of each lens group during zooming from the intermediate focal length state to the telephoto end state.

  As shown in FIG. 29A, in the zoom lens according to the present embodiment, the first lens group G1 having a negative refractive power and the second lens having a positive refractive power are sequentially arranged from the object side along the optical axis. It is composed of a lens group G2, a third lens group G3 having a negative refractive power, a fourth lens group G4 having a positive refractive power, and a fifth lens group G5 having a positive refractive power.

  The first lens group G1 includes, in order from the object side along the optical axis, a negative meniscus lens L11 having a convex surface directed toward the object side, a negative meniscus lens L12 having a convex surface directed toward the object side, a biconcave lens L13, and a biconvex lens. And L14. The negative meniscus lens L11 is an aspherical lens in which the object-side lens surface and the image-side lens surface have an aspherical shape. The negative meniscus lens L12 is an aspherical lens having an aspherical surface on the image side.

The second lens group G2 includes, in order from the object side along the optical axis, a second F lens group G2F having a positive refractive power and a second R lens group G2R having a positive refractive power.
The second F lens group G2F is composed of, in order from the object side along the optical axis, a cemented lens of a biconvex lens L21 and a negative meniscus lens L22 having a concave surface facing the object side, and a biconcave lens L23. The biconvex lens L21 is an aspherical lens having an aspherical surface on the object side.
The second R lens group G2R is composed of, in order from the object side along the optical axis, a cemented lens of a negative meniscus lens L24 having a convex surface facing the object side, a biconvex lens L25, and a negative meniscus lens L26 having a concave surface facing the object side. Has been done. The negative meniscus lens L24 is an aspherical lens having an aspherical surface on the object side.

  The third lens group G3 is composed of an aperture stop S, a cemented lens of a biconcave lens L31 and a positive meniscus lens L32 having a convex surface directed toward the object side, and a flare cut stop FS in order from the object side along the optical axis. Has been done.

  The fourth lens group G4 includes, in order from the object side along the optical axis, a cemented lens of a biconvex lens L41 and a negative meniscus lens L42 having a concave surface facing the object side, and a negative meniscus lens L43 having a convex surface facing the object side. It is composed of a cemented lens with a positive meniscus lens L44 having a convex surface facing the object side. The negative meniscus lens L42 is an aspherical lens having an aspherical surface on the image side.

  The fifth lens group G5 is composed of a positive meniscus lens L51 having a concave surface facing the object side. The positive meniscus lens L51 is an aspherical lens having an aspherical surface on the object side and the image side.

  On the image plane I, an image pickup device (not shown) composed of CCD, CMOS or the like is arranged.

  With the above-described configuration, in the zoom lens according to the present embodiment, the distance between the first lens group G1 and the second lens group G2 decreases during zooming from the wide-angle end state to the telephoto end state, and the second lens group The distance between the lens group G2 and the third lens group G3 increases, the distance between the third lens group G3 and the fourth lens group G4 decreases, and the distance between the fourth lens group G4 and the fifth lens group G5 increases. As described above, the first lens group G1, the second lens group G2, the third lens group G4, and the fourth lens group G4 move along the optical axis with respect to the image plane I. Specifically, during zooming, the first lens group G1 once moves to the image plane I side and then to the object side, and the second lens group G2 and the fourth lens group G4 move integrally to the object side. The third lens group G3 moves toward the object side, and the fifth lens group G5 is fixed with respect to the image plane I.

  The aperture stop S is arranged between the second lens group G2 and the third lens group G3, and moves together with the third lens group G3 during zooming from the wide-angle end state to the telephoto end state.

  Further, in the zoom lens according to the present embodiment, by moving the second F lens group G2F to the image plane I side, focusing from an object at infinity to a near object is performed.

  In the zoom lens according to the present embodiment, the cemented lens of the biconvex lens L41 in the fourth lens group G4 and the negative meniscus lens L42 having the concave surface facing the object side is used as a vibration isolation lens group in the direction orthogonal to the optical axis. By moving in the direction including the component, image plane correction, that is, image stabilization is performed when an image blur occurs.

Here, when the focal length of the entire zoom lens system according to the present embodiment is f and the ratio of the amount of movement of the image on the image plane I to the amount of movement of the image stabilizing lens group during blur correction is K, the angle is In order to correct the rotational shake of θ, it is sufficient to shift the antivibration lens group by (f · tan θ) / K in the direction orthogonal to the optical axis.
In the wide-angle end state, the zoom lens according to the present example has a vibration isolation coefficient K of 0.84 and a focal length of 16.48 (mm) (see Table 8 below), so that 0.81 ° The movement amount of the anti-vibration lens unit for correcting the rotational shake is 0.28 (mm). Further, in the intermediate focal length state, the image stabilization coefficient K is 1.12 and the focal length is 25.21 (mm) (see Table 8 below), so to correct the rotational shake of 0.66 °. The movement amount of the image stabilizing lens unit is 0.26 (mm). In addition, in the telephoto end state, the image stabilization coefficient K is 1.39 and the focal length is 33.94 (mm) (see Table 8 below). Therefore, in order to correct the rotational shake of 0.57 °, The movement amount of the image stabilizing lens unit is 0.24 (mm).

  Table 8 below lists specifications of the zoom lens according to Example 8.

(Table 8) Eighth Example [Overall specifications]
W M T
f 16.48 25.21 33.94
FNO 4.00 4.00 4.00
ω 54.1 40.0 31.8
Y 21.64 21.64 21.64
TL 156.155 150.831 154.903
BF 18.066 18.053 18.060

[Surface data]
Surface number rd nd νd
Object ∞
* 1) 193.58721 2.000 1.82080 42.7
* 2) 20.02145 6.905
3) 90.01817 2.000 1.90043 37.4
* 4) 27.89307 9.933
5) -41.38646 2.000 1.49782 82.6
6) 388.04959 0.150
7) 63.78120 5.582 2.00100 29.1
8) -140.47475 (variable)

* 9) 34.11887 7.683 1.58313 59.4
10) -23.19093 1.500 1.65844 50.8
11) -43.34847 0.150
12) -133.64479 1.500 1.51742 52.2
13) 43.43678 (variable)

* 14) 43.27875 1.500 1.79504 28.7
15) 26.75575 9.166 1.48749 70.3
16) -21.47016 1.500 1.68893 31.2
17) -29.83058 (variable)

18) (Aperture) ∞ 4.000
19) -117.95737 1.500 1.74400 44.8
20) 20.54277 3.285 1.80244 25.6
21) 54.89929 1.000
22) (FS) ∞ (variable)

23) 32.72024 9.645 1.49782 82.6
24) -23.86366 1.500 1.88202 37.2
* 25) -34.86203 0.150
26) 69.62430 1.500 1.90043 37.4
27) 18.05008 9.020 1.49782 82.6
28) 104.94552 (variable)

* 29) -135.00000 4.710 1.77250 49.5
* 30) -48.92153 (BF)
Image plane ∞

[Lens group data]
Starting surface Focal length
G1 1 -23.31
G2 9 35.87
G3 18 -54.84
G4 23 83.18
G5 29 97.01

[Aspherical data]
Surface number: 1
κ = 2.00000E + 00
A4 = 7.90218E-06
A6 = -3.67128E-09
A8 = 1.11425E-12
A10 = -3.22487E-16

Surface number: 2
κ = 9.06000E-02
A4 = -1.10492E-05
A6 = 4.18700E-08
A8 = -2.82799E-11
A10 = 8.48422E-14

Surface number: 4
κ = 1.00000E + 00
A4 = 2.06544E-05
A6 = 1.14896E-09
A8 = -9.32488E-11
A10 = 1.06908E-13

Surface number: 9
κ = 1.00000E + 00
A4 = -5.99937E-06
A6 = -8.64207E-09
A8 = 0.00000E + 00
A10 = 0.00000E + 00

Surface number: 14
κ = 1.00000E + 00
A4 = -5.24242E-06
A6 = 3.78138E-09
A8 = -1.26184E-11
A10 = -1.01048E-14

Surface number: 25
κ = 1.00000E + 00
A4 = 5.70046E-06
A6 = -3.54520E-09
A8 = 1.13461E-11
A10 = -1.29870E-13

Surface number: 29
κ = 1.00000E + 00
A4 = 2.14047E-06
A6 = -2.58918E-09
A8 = 4.54444E-11
A10 = -7.04486E-14

Surface number: 30
κ = 1.00000E + 00
A4 = 5.01764E-06
A6 = -9.55833E-09
A8 = 5.69307E-11
A10 = -7.79067E-14

[Variable interval data]
W M T W M T
Infinity infinity infinity infinity short range short range short range
d 0 ∞ ∞ ∞ 116.21 121.52 117.46
β − − − -0.1183 -0.1768 -0.2470
f 16.48 25.21 33.94 − − −
d 8 27.092 8.876 0.500 30.852 12.622 4.589
d13 7.348 7.348 7.348 3.588 3.603 3.259
d17 2.000 6.293 9.740 2.000 6.293 9.740
d22 9.240 4.947 1.500 9.240 4.947 1.500
d28 4.528 17.433 29.874 4.528 17.433 29.874
BF 18.066 18.053 18.060 18.146 18.232 18.406

[Values corresponding to each conditional expression]
(1) f5 / (-f1) = 4.162
(2) | m12 | /fw=1.614
(3) f5 / f4 = 1.166

30 (a), 30 (b), and 30 (c) show focusing of an object at infinity in the wide-angle end state, intermediate focal length state, and telephoto end state of the zoom lens according to Example 8, respectively. FIG. 7 is a diagram of various types of aberration of FIG.
31 (a), 31 (b), and 31 (c) show focusing of a short-distance object in the wide-angle end state, intermediate focal length state, and telephoto end state of the zoom lens according to Example 8, respectively. FIG. 7 is a diagram of various types of aberration of FIG.
32 (a), 32 (b), and 32 (c) are the meridional laterals during image stabilization in the wide-angle end state, the intermediate focal length state, and the telephoto end state of the zoom lens according to Example 8, respectively. It is an aberration diagram.

  As is clear from each aberration diagram, the zoom lens according to Example 8 is properly corrected for various aberrations from the wide-angle end state to the telephoto end state, and has high optical performance even during vibration isolation. I understand.

(Ninth embodiment)
33A, 33B, and 33C are cross-sectional views of the zoom lens according to Example 9 in the wide-angle end state, the intermediate focal length state, and the telephoto end state, respectively.
The arrow below each lens group in FIG. 33A indicates the moving direction of each lens group during zooming from the wide-angle end state to the intermediate focal length state. The arrow below each lens group in FIG. 33B indicates the moving direction of each lens group during zooming from the intermediate focal length state to the telephoto end state.

  As shown in FIG. 33A, in the zoom lens according to the present embodiment, the first lens group G1 having a negative refractive power and the second lens group having a positive refractive power are arranged in this order from the object side along the optical axis. It includes a lens group G2, an aperture stop S, a third lens group G3 having a negative refractive power, a fourth lens group G4 having a positive refractive power, and a fifth lens group G5 having a positive refractive power. Has been done.

  The first lens group G1 includes, in order from the object side along the optical axis, a negative meniscus lens L11 having a convex surface directed toward the object side, a negative meniscus lens L12 having a convex surface directed toward the object side, a biconcave lens L13, and a biconvex lens. And L14. The negative meniscus lens L11 is an aspherical lens in which the object-side lens surface and the image-side lens surface have an aspherical shape. The negative meniscus lens L12 is an aspherical lens having an aspherical surface on the image side.

  The second lens group G2 has, in order from the object side along the optical axis, a cemented lens of a biconvex lens L21 and a negative meniscus lens L22 having a concave surface facing the object side, a biconcave lens L23, and a convex surface facing the object side. It is composed of a negative meniscus lens L24, a biconvex lens L25, and a cemented lens of a negative meniscus lens L26 having a concave surface facing the object side. The biconvex lens L21 is an aspherical lens having an aspherical surface on the object side. The negative meniscus lens L24 is an aspherical lens having an aspherical surface on the object side.

  The third lens group G3 is composed of a cemented lens of a biconcave lens L31 and a positive meniscus lens L32 having a convex surface directed toward the object side.

  The fourth lens group G4 includes, in order from the object side along the optical axis, a cemented lens of a biconvex lens L41 and a negative meniscus lens L42 having a concave surface facing the object side, and a negative meniscus lens L43 having a convex surface facing the object side. It is composed of a cemented lens with a positive meniscus lens L44 having a convex surface facing the object side. The negative meniscus lens L42 is an aspherical lens having an aspherical surface on the image side.

  The fifth lens group G5 is composed of a positive meniscus lens L51 having a concave surface facing the object side. The positive meniscus lens L51 is an aspherical lens having an aspherical surface on the object side and the image side.

  On the image plane I, an image pickup device (not shown) composed of CCD, CMOS or the like is arranged.

  With the above-described configuration, in the zoom lens according to the present embodiment, the distance between the first lens group G1 and the second lens group G2 decreases during zooming from the wide-angle end state to the telephoto end state, and the second lens group The distance between the lens group G2 and the third lens group G3 increases, the distance between the third lens group G3 and the fourth lens group G4 decreases, and the distance between the fourth lens group G4 and the fifth lens group G5 increases. As described above, the first lens group G1, the second lens group G2, the third lens group G4, the fourth lens group G4, and the fifth lens group move along the optical axis with respect to the image plane I. Specifically, during zooming, the first lens group G1 once moves to the image plane I side and then to the object side, and the second lens group G2 and the fourth lens group G4 move integrally to the object side. Then, the third lens group G3 moves to the object side, and the fifth lens group G5 moves to the image plane I side.

  The aperture stop S is arranged between the second lens group G2 and the third lens group G3, and moves integrally with the third lens group G3 during zooming from the wide-angle end state to the telephoto end state.

  Further, in the zoom lens according to the present embodiment, by moving the third lens group G3 toward the image plane I, focusing from an object at infinity to a near object is performed.

  In the zoom lens according to the present embodiment, a cemented lens of the negative meniscus lens L24 having a convex surface facing the object side in the second lens group G2, the biconvex lens L25, and the negative meniscus lens L26 having a concave surface facing the object side is formed. The image stabilizing lens unit is moved in a direction including a component in a direction orthogonal to the optical axis to correct the image surface when an image blur occurs, that is, to perform image stabilization.

Here, when the focal length of the entire zoom lens system according to the present embodiment is f and the ratio of the amount of movement of the image on the image plane I to the amount of movement of the image stabilizing lens group during blur correction is K, the angle is In order to correct the rotational shake of θ, it is sufficient to shift the antivibration lens group by (f · tan θ) / K in the direction orthogonal to the optical axis.
In the wide-angle end state, the zoom lens according to the present example has a vibration isolation coefficient K of 1.06 and a focal length of 16.48 (mm) (see Table 9 below), so that 0.81 ° The movement amount of the anti-vibration lens group for correcting the rotational shake is 0.22 (mm). Further, in the intermediate focal length state, the image stabilization coefficient K is 1.32 and the focal length is 25.21 (mm) (see Table 9 below), so to correct the rotational shake of 0.66 °. The movement amount of the image stabilizing lens unit is 0.22 (mm). Further, in the telephoto end state, the image stabilization coefficient K is 1.64 and the focal length is 33.95 (mm) (see Table 9 below). Therefore, in order to correct the rotational shake of 0.57 °, The movement amount of the image stabilizing lens unit is 0.20 (mm).

  Table 9 below lists specifications of the zoom lens according to the ninth example.

(Table 9) Ninth Example [Overall Specifications]
W M T
f 16.48 25.21 33.95
FNO 4.00 4.00 4.00
ω 54.0 39.4 31.8
Y 21.64 21.64 21.64
TL 162.365 154.491 161.772
BF 23.901 22.523 18.067

[Surface data]
Surface number rd nd νd
Object ∞
* 1) 206.62948 2.000 1.82080 42.7
* 2) 22.78595 5.394
3) 79.60930 2.000 1.90043 37.4
* 4) 28.62293 12.227
5) -36.79633 2.000 1.49782 82.6
6) 138.93269 0.150
7) 59.13309 5.614 2.00100 29.1
8) -157.09491 (variable)

* 9) 78.52593 8 .740 1.58313 59.4
10) -18.33622 1.500 1.65844 50.8
11) -31.62205 0.320
12) -53.95141 1.500 1.51742 52.2
13) 1642.72200 5.830
* 14) 56.55132 1.500 1.79504 28.7
15) 30.04155 10.867 1.48749 70.3
16) -20.18962 1.500 1.68893 31.2
17) -26.35355 (variable)

18) (Aperture) ∞ (Variable)

19) -107.45547 1.500 1.74400 44.8
20) 19.22984 3.482 1.80244 25.6
21) 51.40293 (variable)

22) 43.71137 7.983 1.49782 82.6
23) -23.27350 1.500 1.88202 37.2
* 24) -31.21 137 0.150
25) 71.81959 1.500 1.90043 37.4
26) 18.76437 8.473 1.49782 82.6
27) 145.88740 (variable)

* 28) -135.00000 4.550 1.77250 49.5
* 29) -52.15640 (BF)
Image plane ∞

[Lens group data]
Starting surface Focal length
G1 1 -24.38
G2 9 34.96
G3 19 -50.79
G4 22 84.06
G5 28 107.45

[Aspherical data]
Surface number: 1
κ = 0.00000E + 00
A4 = 7.49847E-06
A6 = -4.72101E-09
A8 = 1.34426E-12
A10 = 7.77327E-16

Surface number: 2
κ = 1.11000E-02
A4 = -2.39129E-05
A6 = 4.34446E-08
A8 = -4.32137E-11
A10 = 3.44930E-14

Surface number: 4
κ = 1.00000E + 00
A4 = 3.53137E-05
A6 = 6.78430E-09
A8 = -4.22471E-11
A10 = 4.95919E-14

Surface number: 9
κ = 1.00000E + 00
A4 = -4.89433E-06
A6 = -9.35308E-09
A8 = 0.00000E + 00
A10 = 0.00000E + 00

Surface number: 14
κ = 1.00000E + 00
A4 = -6.54457E-06
A6 = 5.07738E-09
A8 = -5.16352E-11
A10 = 2.09233E-13

Surface number: 24
κ = 1.00000E + 00
A4 = 2.08758E-06
A6 = 1.15759E-08
A8 = -7.29250E-11
A10 = 1.18188E-13

Surface number: 28
κ = 1.00000E + 00
A4 = 2.27203E-06
A6 = 1.20614E-09
A8 = 2.01555E-11
A10 = -4.02390E-14

Surface number: 29
κ = 1.00000E + 00
A4 = 6.10900E-06
A6 = -4.88513E-09
A8 = 2.18415E-11
A10 = -3.91619E-14

[Variable interval data]
W M T W M T
Infinity infinity infinity infinity short range short range short range
d 0 ∞ ∞ ∞ 110.00 117.87 110.60
β − − − -0.1310 -0.1947 -0.2863
f 16.48 25.21 33.95 − − −
d 8 27.288 7.805 0.500 27.288 7.805 0.500
d17 2.000 7.042 8.304 2.000 7.042 8.304
d18 4.000 4.000 4.000 5.664 7.386 9.288
d21 12.429 7.386 6.125 10.765 4.000 0.837
d27 2.468 15.455 34.496 2.468 15.455 34.496
BF 23.901 22.523 18.067 23.999 22.740 18.534

[Values corresponding to each conditional expression]
(1) f5 / (-f1) = 4.408
(2) | m12 | /fw=1.626
(3) f5 / f4 = 1.278

34 (a), 34 (b), and 34 (c) show focusing of an object at infinity in a wide-angle end state, an intermediate focal length state, and a telephoto end state of the zoom lens according to Example 9, respectively. FIG. 7 is a diagram of various types of aberration of FIG.
35 (a), 35 (b), and 35 (c) show focusing of a short-distance object in the wide-angle end state, intermediate focal length state, and telephoto end state of the zoom lens according to the ninth example, respectively. FIG. 7 is a diagram of various types of aberration of FIG.
36 (a), 36 (b), and 36 (c) are respectively the meridional lateral sides at the time of image stabilization in the wide-angle end state, the intermediate focal length state, and the telephoto end state of the zoom lens according to the ninth example. It is an aberration diagram.

  As is clear from each aberration diagram, the zoom lens according to Example 9 is properly corrected for various aberrations from the wide-angle end state to the telephoto end state, and has high optical performance even during vibration isolation. I understand.

(Tenth Example)
37 (a), 37 (b), and 37 (c) are cross-sectional views of the zoom lens according to Example 10 in the wide-angle end state, the intermediate focal length state, and the telephoto end state, respectively.
The arrow below each lens group in FIG. 37A indicates the moving direction of each lens group during zooming from the wide-angle end state to the intermediate focal length state. The arrow below each lens group in FIG. 37 (b) indicates the moving direction of each lens group during zooming from the intermediate focal length state to the telephoto end state.

  As shown in FIG. 37A, in the zoom lens according to the present example, the first lens group G1 having a negative refractive power and the second lens group having a positive refractive power are arranged in this order from the object side along the optical axis. It is composed of a lens group G2, a third lens group G3 having a negative refractive power, a fourth lens group G4 having a positive refractive power, and a fifth lens group G5 having a positive refractive power.

  The first lens group G1 includes, in order from the object side along the optical axis, a negative meniscus lens L11 having a convex surface directed toward the object side, a negative meniscus lens L12 having a convex surface directed toward the object side, a biconcave lens L13, and a biconvex lens. And L14. The negative meniscus lens L11 is an aspherical lens in which the object-side lens surface and the image-side lens surface have an aspherical shape. The negative meniscus lens L12 is an aspherical lens having an aspherical surface on the image side.

  The second lens group G2 has, in order from the object side along the optical axis, a cemented lens of a biconvex lens L21 and a negative meniscus lens L22 having a concave surface facing the object side, a biconcave lens L23, and a convex surface facing the object side. It is composed of a negative meniscus lens L24, a biconvex lens L25, and a cemented lens of a negative meniscus lens L26 having a concave surface facing the object side. The biconvex lens L21 is an aspherical lens having an aspherical surface on the object side. The negative meniscus lens L24 is an aspherical lens having an aspherical surface on the object side.

  The third lens group G3 includes, in order from the object side along the optical axis, an aperture stop S, and a cemented lens of a biconcave lens L31 and a positive meniscus lens L32 having a convex surface directed toward the object side.

The fourth lens group G4 includes, in order from the object side along the optical axis, a fourth F lens group G4F having a positive refractive power and a fourth R lens group G4R having a negative refractive power.
The fourth F lens group G4F is composed of a cemented lens of a biconvex lens L41 and a negative meniscus lens L42 having a concave surface facing the object side. The negative meniscus lens L42 is an aspherical lens having an aspherical surface on the image side.
The fourth R lens group G4R is composed of a cemented lens of a negative meniscus lens L43 having a convex surface facing the object side and a positive meniscus lens L44 having a convex surface facing the object side.

  The fifth lens group G5 is composed of a positive meniscus lens L51 having a concave surface facing the object side. The positive meniscus lens L51 is an aspherical lens having an aspherical surface on the object side and the image side.

  On the image plane I, an image pickup device (not shown) composed of CCD, CMOS or the like is arranged.

  With the above-described configuration, in the zoom lens according to the present embodiment, the distance between the first lens group G1 and the second lens group G2 decreases during zooming from the wide-angle end state to the telephoto end state, and the second lens group The distance between the lens group G2 and the third lens group G3 increases, the distance between the third lens group G3 and the fourth lens group G4 decreases, and the distance between the fourth lens group G4 and the fifth lens group G5 increases. As described above, the first lens group G1, the second lens group G2, the third lens group G4, the fourth lens group G4, and the fifth lens group move along the optical axis with respect to the image plane I. Specifically, during zooming, the first lens group G1 once moves to the image plane I side and then to the object side, and the second lens group G2 and the fourth lens group G4 move integrally to the object side. Then, the third lens group G3 moves to the object side, and the fifth lens group G5 once moves to the object side and then moves to the image plane I side.

  The aperture stop S is arranged between the second lens group G2 and the third lens group G3, and moves together with the third lens group G3 during zooming from the wide-angle end state to the telephoto end state.

  Further, in the zoom lens according to the present embodiment, by moving the fourth F lens group G4F toward the object side, focusing from an object at infinity to a near object is performed.

  Further, the zoom lens according to the present embodiment is a cemented lens of the negative meniscus lens L24 having a convex surface facing the object side in the second lens group G2, the biconvex lens L25, and the negative meniscus lens L26 having a concave surface facing the object side. The image stabilizing lens unit is moved in a direction including a component in a direction orthogonal to the optical axis to correct the image surface when an image blur occurs, that is, to perform image stabilization.

Here, when the focal length of the entire zoom lens system according to the present embodiment is f and the ratio of the amount of movement of the image on the image plane I to the amount of movement of the image stabilizing lens group during blur correction is K, the angle is In order to correct the rotational shake of θ, it is sufficient to shift the antivibration lens group by (f · tan θ) / K in the direction orthogonal to the optical axis.
In the wide-angle end state, the zoom lens according to the present example has an image stabilization coefficient K of 1.01 and a focal length of 16.48 (mm) (see Table 10 below), so 0.81 ° The movement amount of the anti-vibration lens unit for correcting the rotational shake is 0.23 (mm). Further, in the intermediate focal length state, the image stabilization coefficient K is 1.28 and the focal length is 25.22 (mm) (see Table 10 below), so to correct the rotational blur of 0.66 °. The movement amount of the image stabilizing lens group is 0.23 (mm). In addition, in the telephoto end state, the image stabilization coefficient K is 1.58 and the focal length is 33.95 (mm) (see Table 10 below), so to correct rotational shake of 0.57 °. The movement amount of the image stabilizing lens unit is 0.21 (mm).

  Table 10 below lists specifications of the zoom lens according to Example 10.

(Table 10) Tenth Example [Overall Specifications]
W M T
f 16.48 25.22 33.95
FNO 4.00 4.00 4.00
ω 54.0 39.5 31.8
Y 21.64 21.64 21.64
TL 157.040 150.577 158.386
BF 19.612 20.204 18.091

[Surface data]
Surface number rd nd νd
Object ∞
* 1) 748.12416 2.000 1.82080 42.7
* 2) 24.27981 6.249
3) 82.72688 2.000 1.90043 37.4
* 4) 29.19843 11.941
5) -38.35396 2.000 1.49782 82.6
6) 123.88139 0.150
7) 58.33566 5.662 2.00100 29.1
8) -157.62198 (variable)

* 9) 53.58324 6.922 1.58313 59.4
10) -22.47903 1.500 1.65454 55.0
11) -43.36840 0.150
12) -111.21206 1.500 1.51742 52.2
13) 108.52980 7.626
* 14) 45.76109 1.500 1.82227 25.8
15) 27.94575 10.712 1.48749 70.3
16) -23.08227 1.500 1.68893 31.2
17) -31.09319 (variable)

18) (Aperture) ∞ 4.000
19) -95.69123 1.500 1.74400 44.8
20) 28.24642 3.135 1.80244 25.6
21) 114.16154 (variable)

22) 45.66871 6.767 1.49782 82.6
23) -24.10121 1.500 1.88202 37.2
* 24) -36.88706 (variable)

25) 51.43628 1.500 1.90043 37.4
26) 17.97428 6.908 1.49782 82.6
27) 53.78862 (variable)

* 28) -135.00000 4.998 1.77250 49.5
* 29) -46.24500 (BF)
Image plane ∞

[Lens group data]
Starting surface Focal length
G1 1 -24.13
G2 9 36.72
G3 18 -77.89
G4 22 151.54
G5 28 88.87

[Aspherical data]
Surface number: 1
κ = 0.00000E + 00
A4 = 9.52593E-06
A6 = -6.95106E-09
A8 = 1.81770E-12
A10 = 4.34677E-16

Surface number: 2
κ = 1.04000E-01
A4 = -2.28424E-05
A6 = 3.85220E-08
A8 = -4.02855E-11
A10 = 2.50646E-14

Surface number: 4
κ = 1.00000E + 00
A4 = 3.45313E-05
A6 = 2.43926E-08
A8 = -5.26585E-11
A10 = -1.44105E-14

Surface number: 9
κ = 1.00000E + 00
A4 = -3.39462E-06
A6 = -4.52751E-09
A8 = 0.00000E + 00
A10 = 0.00000E + 00

Surface number: 14
κ = 1.00000E + 00
A4 = -3.99540E-06
A6 = 6.90128E-09
A8 = -7.15162E-11
A10 = 2.30252E-13

Surface number: 24
κ = 1.00000E + 00
A4 = 2.95224E-06
A6 = 6.31531E-09
A8 = -6.95778E-11
A10 = 9.58472E-14

Surface number: 28
κ = 1.00000E + 00
A4 = 3.07452E-06
A6 = 6.73524E-10
A8 = 1.35472E-11
A10 = -3.33968E-14

Surface number: 29
κ = 1.00000E + 00
A4 = 7.09095E-06
A6 = -3.53806E-09
A8 = 1.19967E-11
A10 = -2.88780E-14

[Variable interval data]
W M T W M T
Infinity infinity infinity infinity short range short range short range
d 0 ∞ ∞ ∞ 115.33 121.81 114.01
β − − − -0.1237 -0.1846 -0.2688
f 16.48 25.22 33.95 − − −
d 8 26.754 7.684 0.500 26.754 7.684 0.500
d17 2.000 7.900 9.425 2.000 7.900 9.425
d21 11.786 5.887 4.361 10.002 2.909 0.209
d24 0.150 0.150 0.150 1.935 3.128 4.301
d27 5.019 17.035 34.140 5.019 17.035 34.140
BF 19.612 20.204 18.091 19.700 20.399 18.504

[Values corresponding to each conditional expression]
(1) f5 / (-f1) = 3.682
(2) | m12 | /fw=1.593
(3) f5 / f4 = 0.586

38 (a), 38 (b), and 38 (c) show focusing of an object at infinity in the wide-angle end state, intermediate focal length state, and telephoto end state of the zoom lens according to Example 10, respectively. FIG. 7 is a diagram of various types of aberration of FIG.
39 (a), 39 (b), and 39 (c) show focusing of a short-distance object in a wide-angle end state, an intermediate focal length state, and a telephoto end state of the zoom lens according to Example 10, respectively. FIG. 7 is a diagram of various types of aberration of FIG.
40 (a), 40 (b), and 40 (c) are the meridional laterals during image stabilization in the wide-angle end state, intermediate focal length state, and telephoto end state of the zoom lens according to Example 10, respectively. It is an aberration diagram.

  As is clear from each aberration diagram, the zoom lens of the tenth example has various aberrations favorably corrected from the wide-angle end state to the telephoto end state, and has high optical performance even during image stabilization. I understand.

(Eleventh embodiment)
41A, 41B, and 41C are cross-sectional views of the zoom lens according to Example 11 in the wide-angle end state, the intermediate focal length state, and the telephoto end state, respectively.
The arrow below each lens group in FIG. 41A indicates the moving direction of each lens group during zooming from the wide-angle end state to the intermediate focal length state. The arrow below each lens group in FIG. 41B indicates the moving direction of each lens group during zooming from the intermediate focal length state to the telephoto end state.

  As shown in FIG. 41A, in the zoom lens according to the present embodiment, the first lens group G1 having a negative refractive power and the second lens having a positive refractive power are arranged in this order from the object side along the optical axis. It is composed of a lens group G2, a third lens group G3 having a negative refractive power, a fourth lens group G4 having a positive refractive power, and a fifth lens group G5 having a positive refractive power.

  The first lens group G1 includes, in order from the object side along the optical axis, a negative meniscus lens L11 having a convex surface directed toward the object side, a negative meniscus lens L12 having a convex surface directed toward the object side, a biconcave lens L13, and a biconvex lens. And L14. The negative meniscus lens L11 is an aspherical lens in which the object-side lens surface and the image-side lens surface have an aspherical shape. The negative meniscus lens L12 is an aspherical lens having an aspherical surface on the image side.

  The second lens group G2 has, in order from the object side along the optical axis, a cemented lens of a biconvex lens L21 and a negative meniscus lens L22 having a concave surface facing the object side, a biconcave lens L23, and a convex surface facing the object side. It is composed of a negative meniscus lens L24, a biconvex lens L25, and a cemented lens of a negative meniscus lens L26 having a concave surface facing the object side. The biconvex lens L21 is an aspherical lens having an aspherical surface on the object side. The negative meniscus lens L24 is an aspherical lens having an aspherical surface on the object side.

  The third lens group G3 is composed of an aperture stop S, a cemented lens of a biconcave lens L31 and a positive meniscus lens L32 having a convex surface directed toward the object side, and a flare cut stop FS in order from the object side along the optical axis. Has been done.

  The fourth lens group G4 includes, in order from the object side along the optical axis, a cemented lens of a biconvex lens L41 and a negative meniscus lens L42 having a concave surface facing the object side, and a negative meniscus lens L43 having a convex surface facing the object side. It is composed of a cemented lens with a biconvex lens L44. The negative meniscus lens L42 is an aspherical lens having an aspherical surface on the image side.

  The fifth lens group G5 is composed of a positive meniscus lens L51 having a concave surface facing the object side. The positive meniscus lens L51 is an aspherical lens having an aspherical surface on the object side and the image side.

  On the image plane I, an image pickup device (not shown) composed of CCD, CMOS or the like is arranged.

  With the above-described configuration, in the zoom lens according to the present embodiment, the distance between the first lens group G1 and the second lens group G2 decreases during zooming from the wide-angle end state to the telephoto end state, and the second lens group The distance between the lens group G2 and the third lens group G3 increases, the distance between the third lens group G3 and the fourth lens group G4 decreases, and the distance between the fourth lens group G4 and the fifth lens group G5 increases. As described above, the first lens group G1, the second lens group G2, the third lens group G4, the fourth lens group G4, and the fifth lens group move along the optical axis with respect to the image plane I. Specifically, during zooming, the first lens group G1 once moves to the image plane I side and then to the object side, and the second lens group G2 and the fourth lens group G4 move integrally to the object side. Then, the third lens group G3 moves to the object side, and the fifth lens group G5 once moves to the object side and then moves to the image plane I side.

  The aperture stop S is arranged between the second lens group G2 and the third lens group G3, and moves together with the third lens group G3 during zooming from the wide-angle end state to the telephoto end state.

  Further, in the zoom lens according to the present embodiment, by moving the fifth lens group G5 toward the object side, focusing from an object at infinity to a near object is performed.

  In the zoom lens according to the present embodiment, a cemented lens of the negative meniscus lens L24 having a convex surface facing the object side in the second lens group G2, the biconvex lens L25, and the negative meniscus lens L26 having a concave surface facing the object side is formed. The image stabilizing lens unit is moved in a direction including a component in a direction orthogonal to the optical axis to correct the image surface when an image blur occurs, that is, to perform image stabilization.

Here, when the focal length of the entire zoom lens system according to the present embodiment is f and the ratio of the amount of movement of the image on the image plane I to the amount of movement of the image stabilizing lens group during blur correction is K, the angle is In order to correct the rotational shake of θ, it is sufficient to shift the antivibration lens group by (f · tan θ) / K in the direction orthogonal to the optical axis.
In the wide-angle end state, the zoom lens according to the present example has an image stabilization coefficient K of 0.97 and a focal length of 16.48 (mm) (see Table 11 below), so that 0.81 ° The movement amount of the anti-vibration lens group for correcting the rotational shake is 0.24 (mm). Further, in the intermediate focal length state, the image stabilization coefficient K is 1.19 and the focal length is 25.21 (mm) (see Table 11 below), so to correct the rotational blur of 0.66 °. The movement amount of the image stabilizing lens unit is 0.24 (mm). In addition, in the telephoto end state, the image stabilization coefficient K is 1.43 and the focal length is 33.94 (mm) (see Table 11 below). Therefore, in order to correct the rotational shake of 0.57 °, The movement amount of the image stabilizing lens unit is 0.23 (mm).

  Table 11 below lists specifications of the zoom lens according to Example 11.

(Table 11) Eleventh Example [Overall Specifications]
W M T
f 16.48 25.21 33.94
FNO 4.00 4.00 4.00
ω 54.1 40.4 32.8
Y 21.64 21.64 21.64
TL 162.327 153.706 157.417
BF 18.026 19.051 18.015

[Surface data]
Surface number rd nd νd
Object ∞
* 1) 132.59820 2.000 1.82080 42.7
* 2) 19.32271 7.442
3) 160.87743 2.000 1.90043 37.4
* 4) 32.91214 9.741
5) -38.07464 2.000 1.49782 82.6
6) 561.24096 0.150
7) 73.09225 5.033 2.00100 29.1
8) -129.44599 (variable)

* 9) 40.27118 7.618 1.58313 59.4
10) -22.79658 1.500 1.65160 58.6
11) -37.12857 2.061
12) -39.17300 1.500 1.51742 52.2
13) 1874.52540 1.776
* 14) 51.35062 1.500 1.79504 28.7
15) 28.77558 8.221 1.48749 70.3
16) -23.13956 1.500 1.68893 31.2
17) -31.27181 (variable)

18) (Aperture) ∞ 4.000
19) -105.52859 1.500 1.74400 44.8
20) 25.92479 2.859 1.80244 25.6
21) 69.72964 1.000
22) (FS) ∞ (variable)

23) 65.71858 10.859 1.49782 82.6
24) -19.28535 1.500 1.88202 37.2
* 25) -31.97958 0.150
26) 89.97758 1.500 1.90043 37.4
27) 24.75006 11.838 1.49782 82.6
28) -103.72759 (variable)

* 29) -135.00000 4.892 1.77250 49.5
* 30) -59.90604 (BF)
Image plane ∞

[Lens group data]
Starting surface Focal length
G1 1 -21.74
G2 9 34.29
G3 18 -60.80
G4 23 73.88
G5 29 135.56

[Aspherical data]
Surface number: 1
κ = 0.00000E + 00
A4 = 1.16094E-05
A6 = -9.06420E-09
A8 = 2.81639E-12
A10 = 2.24774E-15

Surface number: 2
κ = 1.30300E-01
A4 = -1.18813E-05
A6 = 5.68936E-08
A8 = -9.29931E-11
A10 = 2.59824E-14

Surface number: 4
κ = 1.00000E + 00
A4 = 2.67754E-05
A6 = -6.40784E-09
A8 = -5.02628E-11
A10 = 2.60885E-13

Surface number: 9
κ = 1.00000E + 00
A4 = -2.85903E-06
A6 = -6.888788E-09
A8 = 0.00000E + 00
A10 = 0.00000E + 00

Surface number: 14
κ = 1.00000E + 00
A4 = -4.52862E-06
A6 = 3.83779E-09
A8 = -2.25240E-11
A10 = 7.59629E-14

Surface number: 25
κ = 1.00000E + 00
A4 = 4.32494E-06
A6 = 5.82097E-09
A8 = -4.56667E-11
A10 = 3.78592E-14

Surface number: 29
κ = 1.00000E + 00
A4 = 9.68518E-06
A6 = -2.01079E-08
A8 = 1.31643E-11
A10 = -2.09414E-15

Surface number: 30
κ = 1.00000E + 00
A4 = 8.93441E-06
A6 = -2.666479E-08
A8 = 2.35900E-11
A10 = -9.65459E-15

[Variable interval data]
W M T W M T
Infinity infinity infinity infinity short range short range short range
d 0 ∞ ∞ ∞ 230.00 238.63 234.90
β − − − -0.0651 -0.0951 -0.1271
f 16.48 25.21 33.94 − − −
d 8 29.064 8.952 0.500 29.064 8.952 0.500
d17 2.000 9.683 15.225 2.000 9.683 15.225
d22 14.725 7.042 1.500 14.725 7.042 1.500
d28 4.371 14.839 28.037 0.147 6.667 14.415
BF 18.026 19.051 18.015 22.275 22.275 31.731

[Values corresponding to each conditional expression]
(1) f5 / (-f1) = 6.234
(2) | m12 | /fw=1.734
(3) f5 / f4 = 1.835

42 (a), 42 (b), and 42 (c) show focusing of an object at infinity in the wide-angle end state, intermediate focal length state, and telephoto end state of the zoom lens according to Example 11, respectively. FIG. 7 is a diagram of various types of aberration of FIG.
43 (a), 43 (b), and 43 (c) show focusing of a short-distance object in the wide-angle end state, intermediate focal length state, and telephoto end state of the zoom lens according to Example 11, respectively. FIG. 7 is a diagram of various types of aberration of FIG.
44 (a), 44 (b), and 44 (c) are the meridional laterals during image stabilization in the wide-angle end state, the intermediate focal length state, and the telephoto end state of the zoom lens according to Example 11, respectively. It is an aberration diagram.

  As is apparent from each aberration diagram, the zoom lens according to Example 11 has good correction of various aberrations from the wide-angle end state to the telephoto end state, and also has high optical performance during image stabilization. I understand.

  As described above, according to each of the above-described embodiments, it is possible to realize a zoom lens having a bright F number and high optical performance. In particular, in a zoom lens with a zoom ratio of about 1.5 to 2.5, to realize a zoom lens with an F number of about 2.8 to 4.0 and a wide angle of view. You can Further, the vibration proof lens group can be downsized, and high optical performance can be exhibited even during vibration proof. Further, according to each of the above-described embodiments, it is possible to realize a zoom lens in which the half angle of view (unit: degree) in the wide-angle end state is 39 <ωW <57 (more preferably 42 <ωW <57). .

  In the zoom lens, the half angle of view (unit: degree) in the wide-angle end state is preferably 39 <ωW <57 (more preferably 42 <ωW <57). Further, in the zoom lens, it is preferable that the F number is substantially constant during zooming. Further, in the zoom lens, the motor for moving the focusing lens group is preferably a stepping motor. In the zoom lens, it is preferable that the first lens group G1 temporarily moves to the image plane I side and then moves to the object side during zooming. Further, in the zoom lens, it is preferable that the fifth lens group G5 is fixed with respect to the image plane I during zooming. Further, in the zoom lens, it is preferable that the second lens group G2 and the fourth lens group G4 move to the object side along the same movement locus and have the same movement amount during zooming. Further, in the zoom lens, during zooming, the distance between the first lens group G1 and the second lens group G2 changes, the distance between the second lens group G2 and the third lens group G3 changes, and the third lens It is preferable that the distance between the group G3 and the fourth lens group G4 changes, and the distance between the fourth lens group G4 and the fifth lens group G5 changes.

  It should be noted that each of the above-described examples shows one specific example, and the present embodiment is not limited to these. The following contents can be appropriately adopted as long as the optical performance of the zoom lens is not impaired.

  Although the numerical example of the zoom lens has a five-group configuration, it is also applicable to other group configurations such as six groups. Further, a configuration in which a lens or a lens group is added to the most object side or a configuration in which a lens or a lens group is added to the most image side may be used. The term “lens group” refers to a portion having at least one lens separated by an air gap.

  Further, in the zoom lens, a single lens group or a plurality of lens groups or a partial lens group may be moved in the optical axis direction to form a focusing lens group for focusing from an object at infinity to a near object. The focusing lens group can be applied to autofocus, and is also suitable for driving by a motor for autofocus, for example, an ultrasonic motor. In particular, it is preferable that a part of the second lens group G2 is a focusing lens group, but it is possible to use all or part of the third lens group G3 and the fifth lens group G5 as a focusing lens group. Alternatively, the entire second lens group G2 may be a focusing lens group.

  Also, in a zoom lens, the lens group or partial lens group is moved so as to have a component perpendicular to the optical axis, or is rotated (swinged) in a direction including the optical axis to correct image blur caused by camera shake. It may be a group of anti-vibration lenses. In particular, it is preferable that the whole of the third lens group G3 is the vibration-proof lens group, but the whole or part of the fourth lens group G4 may be the vibration-proof lens group, and part of the third lens group. May be an anti-vibration lens group.

  Further, the lens surface of the lens forming the zoom lens may be a spherical surface or a flat surface, or may be an aspherical surface. When the lens surface is a spherical surface or a flat surface, lens processing and assembly adjustment are facilitated, and deterioration of optical performance due to an error in lens processing and assembly adjustment can be prevented, which is preferable. Further, even if the image plane is deviated, the drawing performance is less deteriorated, which is preferable. When the lens surface is an aspherical surface, either an aspherical surface formed by grinding, a glass mold aspherical surface formed by molding glass into an aspherical shape, or a composite aspherical surface formed by resin on the glass surface 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.

  Further, in the zoom lens, it is preferable that the aperture stop be arranged between the second lens group G2 and the third lens group G3, but its role in the frame of the lens without providing a member as the aperture stop. May be substituted.

  Further, in order to reduce flare and ghosts and achieve high optical performance with high contrast, an antireflection film having a high transmittance in a wide wavelength range may be provided on the lens surface of the zoom lens. .

Next, a camera equipped with a zoom lens will be described based on FIG.
FIG. 45 is a schematic diagram showing the structure of a camera including a zoom lens.
As shown in FIG. 45, the camera 1 is a digital single-lens reflex camera provided with the zoom lens according to the first embodiment as the taking lens 2.
In the digital single-lens reflex camera 1 shown in FIG. 45, light from an object (subject) not shown is condensed by the taking lens 2 and is focused on the focusing plate 5 via the quick return mirror 3. The light imaged on the focusing plate 5 is reflected a plurality of times in the pentaprism 7 and guided to the eyepiece lens 9. This allows the photographer to observe the object (subject) image as an erect image through the eyepiece lens 9.

  When the photographer presses a release button (not shown), the quick return mirror 3 is retracted out of the optical path, and the light of the object (subject) collected by the taking lens 2 forms a subject image on the image sensor 11. As a result, the light from the object is captured by the image sensor 11 and stored in a memory (not shown) as an object image. In this way, the photographer can photograph an object with the camera 1.

  Here, the zoom lens according to the first embodiment mounted on the camera 1 as the taking lens 2 is a zoom lens having a bright F number and high optical performance. Therefore, the camera 1 is a camera having high optical performance. Even if the camera in which the zoom lens according to the second to eleventh embodiments is mounted as the taking lens 2 is configured, the same effect as that of the camera 1 can be obtained. Further, the camera 1 may be one that detachably holds the taking lens 2, or one that is molded integrally with the taking lens 2. Further, the camera 1 may be a camera that does not have a quick return mirror or the like.

  Next, a method of manufacturing the zoom lens will be described. FIG. 46 is a diagram showing the outline of the method of manufacturing the zoom lens.

A method of manufacturing a zoom lens includes a first lens group having a negative refracting power, a second lens group having a positive refracting power, and a third lens having a negative refracting power in order from the object side along an optical axis. A method for manufacturing a zoom lens having a group, a fourth lens group having a positive refractive power, and a fifth lens group, including the following steps S1 and S2 as shown in FIG.
Step S1: Configure to satisfy the following conditional expression (1).
(1) 1.000 <f5 / (-f1) <10.000
However,
f5: Focal length of the fifth lens group f1: Focal length of the first lens group Step S2: During zooming, the interval between the first lens group and the second lens group changes, and the second lens The distance between the lens group and the third lens group changes, the distance between the third lens group and the fourth lens group changes, and the distance between the fourth lens group and the fifth lens group changes. To configure.

  According to such a zoom lens manufacturing method, it is possible to manufacture a zoom lens having a bright F number and high optical performance. In particular, in a zoom lens having a zoom ratio of about 1.5 to 2.5, a zoom lens having an F number of about 2.8 to 4.0 and a wide angle of view should be manufactured. You can

G1 First lens group G2 Second lens group G3 Third lens group G4 Fourth lens group G5 Fifth lens group Gf Focusing lens group S Aperture stop FS Flare cut stop I Image plane 1 Optical device 2 Photographing lens 3 Quick return mirror 5 Focusing plate 7 Penta prism 9 Eyepiece 11 Image sensor

Claims (12)

A first lens group having a negative refractive power, a second lens group having a positive refractive power, a third lens group having a negative refractive power, and a positive refractive power in order from the object side along the optical axis. And a fifth lens group having a positive refracting power, and is substantially composed of five lens groups.
At the time of zooming, the distance between the first lens group and the second lens group changes, the distance between the second lens group and the third lens group changes, and the third lens group and the fourth lens group change. The distance between the lens group changes, the distance between the fourth lens group and the fifth lens group changes,
A zoom lens that satisfies the following conditional expressions.
3.171 ≦ f5 / (− f1) ≦ 4.162
0.200 <f5 / f4 <2.600
However,
f5: focal length of the fifth lens group f1: focal length of the first lens group f4: focal length of the fourth lens group A first lens group having a negative refractive power, a second lens group having a positive refractive power, a third lens group having a negative refractive power, and a positive refractive power in order from the object side along the optical axis. And a fifth lens group having a positive refracting power, and is substantially composed of five lens groups.
At the time of zooming, the distance between the first lens group and the second lens group changes, the distance between the second lens group and the third lens group changes, and the third lens group and the fourth lens group change. The distance between the lens group changes, the distance between the fourth lens group and the fifth lens group changes,
A zoom lens that satisfies the following conditional expressions.
6.234 ≦ f5 / (− f1) <10.000
0.200 <f5 / f4 <2.600
However,
f5: focal length of the fifth lens group f1: focal length of the first lens group f4: focal length of the fourth lens group The zoom lens according to claim 1, which satisfies the following conditional expression.
0.300 <| m12 | / fw <5.000
However,
| M12 |: change amount fw of the distance on the optical axis from the most image-side lens surface of the first lens group to the most object-side lens surface of the second lens group from the wide-angle end state to the telephoto end state : Focal length of the entire zoom lens system in the wide-angle end state   The zoom lens according to claim 1, wherein at least a part of the lenses in the third lens group is configured to be movable so as to include a component in a direction orthogonal to the optical axis.   4. The zoom lens according to claim 1, wherein at least a part of the lenses in the second lens group is configured to be movable so as to include a component in a direction orthogonal to the optical axis.   4. The zoom lens according to claim 1, wherein at least a part of the lenses in the fourth lens group is configured to be movable so as to include a component in a direction orthogonal to the optical axis. 7. The zoom lens according to claim 1, wherein at least a part of the lenses in the second lens group is moved along an optical axis to focus an object at infinity to a near object. .
  The zoom lens according to any one of claims 1 to 6, wherein focusing is performed from an object at infinity to a near object by moving at least a part of lenses in the third lens group along an optical axis. .   7. The zoom lens according to claim 1, wherein at least a part of the lenses in the fourth lens group is moved along the optical axis to focus an object at infinity to a near object. .   The zoom lens according to any one of claims 1 to 6, wherein focusing is performed from an object at infinity to a near object by moving at least a part of lenses in the fifth lens group along an optical axis. .   11. The zoom lens according to claim 1, further comprising an aperture stop between the second lens group and the third lens group.   An optical device comprising the zoom lens according to claim 1.