JP2024044856A - Zoom lens and image capturing device - Google Patents

Abstract

To provide a compact, light-weight zoom lens which offers high optical performance, and an image capturing device.SOLUTION: A zoom lens (30) disclosed herein comprises a negative front group and a positive rear group in order from an object side, the front group comprising a positive lens group G1 (G1) and a negative composite lens group Gn (G2) in order from the object side, and the rear group comprising a positive composite lens group Gp (G3), a negative lens group Gf (G4), and a negative lens group Gr (G5). The zoom lens (30) has specific optical characteristics represented by two specific expressions.SELECTED DRAWING: Figure 1

Description

The present invention relates to a zoom lens and an imaging device.

In recent years, imaging devices using solid-state imaging devices, such as digital still cameras and digital video cameras, have become widespread. Along with this, the optical systems of these imaging devices have become more sophisticated and smaller, and compact imaging device systems are rapidly becoming popular. In particular, for telephoto zoom lenses with long focal lengths, there is a growing demand for higher performance optical systems as well as smaller size and lighter weight.

As a configuration for miniaturizing telephoto zoom lenses, for example, a zoom lens is known that has, in order from the object side, a first lens group with positive refractive power, a second lens group with negative refractive power, a third lens group with positive refractive power, and a lens group with negative refractive power in the rear group, and that changes the magnification by changing the spacing between adjacent lens groups.

As a configuration for shortening the overall optical length of a zoom lens, for example, a zoom lens is known that includes, in order from the object side, a first lens group with positive refractive power, a second lens group with negative refractive power, a third lens group with positive refractive power, a fourth lens group with positive refractive power, and a fifth lens group with negative refractive power, and that shortens the overall length by increasing the composite lateral magnification at the telephoto end of the lens group closer to the image plane than the fifth lens group (see, for example, Patent Document 1).

JP 2014-126850 A

However, the zoom lens described in Patent Document 1 has a configuration in which the first lens group moves toward the object side when changing the magnification. There is room left. Additionally, due to the configuration in which the first lens group, which has the heaviest weight, is moved, the addition to the mechanical components for driving the first lens group becomes large, which may make it difficult to achieve smooth magnification change operation. .

One aspect of the present invention aims to provide a zoom lens and an imaging device that are small, lightweight, and have high optical performance.

In order to solve the above problems, a zoom lens according to one aspect of the present invention includes, in order from the object side, a front group having a negative refractive power and a rear group having a positive refractive power, and the front group has only a lens group G1 having a positive refractive power and a composite lens group Gn having a negative refractive power as lens groups and composite lens groups, in order from the object side, and the rear group includes, in order from the object side, , a composite lens group Gp having a positive refractive power, and a lens group Gf having a negative refractive power, and the rear group further includes a lens group Gr having a negative refractive power closer to the image plane than the lens group Gf. The composite lens group Gn has one or more lens groups, and the composite lens group Gp has one or more lens groups, and when changing the magnification between the wide-angle end and the telephoto end, there is a difference between adjacent lens groups. The distance on the optical axis changes, the lens group G1 is fixed, and when changing the magnification from the wide-angle end to the telephoto end, the lens group Gr moves on the optical axis toward the object side, and during focusing, the lens group G1 is fixed. Group Gf moves on the optical axis and satisfies the following equation.
-0.90≦fr/ft≦-0.03...(1)
1.01≦βrt/βrw≦1.50 (2)
however,
fr: Focal length of the lens group Gr ft: Focal length of the zoom lens at the telephoto end when focusing on infinity βrt: Lateral magnification of the lens group Gr at the telephoto end when focusing on infinity βrw: The lens Lateral magnification at wide-angle end when group Gr is focused at infinity

Moreover, in order to solve the above-mentioned problem, an imaging device according to one aspect of the present invention includes the above-mentioned zoom lens and an optical image formed by the zoom lens provided on the image plane side of the zoom lens. and an image sensor that converts the signal into an electrical signal.

According to one aspect of the present invention, it is possible to provide a zoom lens and an imaging device that are small, lightweight, and have high optical performance.

FIG. 3 is a diagram schematically showing the optical configuration of the zoom lens of Example 1 at the wide-angle end when focusing at infinity. FIG. 3 is a diagram showing longitudinal aberration at the wide-angle end of the zoom lens of Example 1 when focusing at infinity. FIG. 3 is a diagram showing longitudinal aberration of the zoom lens of Example 1 at an intermediate focal length state when focusing at infinity. 4 is a diagram showing longitudinal aberration at the telephoto end when the zoom lens of Example 1 is focused on infinity. FIG. 7 is a diagram schematically showing the optical configuration of the zoom lens of Example 2 at the wide-angle end when focusing at infinity. FIG. 13A and 13B are diagrams illustrating longitudinal aberration at the wide-angle end when the zoom lens of Example 2 is focused on an object at infinity. 13 is a diagram showing longitudinal aberration of the zoom lens of Example 2 in a middle focal length state when focused on infinity. FIG. 13A and 13B are diagrams illustrating longitudinal aberration at the telephoto end when the zoom lens of Example 2 is focused on infinity. FIG. 11 is a diagram illustrating an optical configuration of a zoom lens according to a third embodiment at a wide-angle end when focused on infinity. 7 is a diagram showing longitudinal aberration at the wide-angle end of the zoom lens of Example 3 when focusing at infinity. FIG. FIG. 7 is a diagram showing the longitudinal aberration of the zoom lens of Example 3 at an intermediate focal length state when focusing at infinity. 13A and 13B are diagrams illustrating longitudinal aberration at the telephoto end when the zoom lens of Example 3 is focused on an object at infinity. FIG. 13 is a diagram illustrating an optical configuration of a zoom lens according to a fourth embodiment at a wide-angle end when focused on infinity. FIG. 7 is a diagram showing longitudinal aberration at the wide-angle end of the zoom lens of Example 4 when focusing at infinity. FIG. 7 is a diagram showing longitudinal aberration of the zoom lens of Example 4 at an intermediate focal length state when focusing at infinity. FIG. 7 is a diagram showing longitudinal aberration at the telephoto end of the zoom lens of Example 4 when focusing at infinity. FIG. 13 is a diagram illustrating an optical configuration of a zoom lens according to a fifth embodiment at a wide-angle end when focused on infinity. FIG. 13 is a diagram showing longitudinal aberration at the wide-angle end when the zoom lens of Example 5 is focused on an object at infinity. FIG. 13 is a diagram showing longitudinal aberration of the zoom lens of Example 5 in a middle focal length state when focused on infinity. FIG. 7 is a diagram showing longitudinal aberration at the telephoto end of the zoom lens of Example 5 when focusing at infinity. FIG. 7 is a diagram schematically showing the optical configuration of the zoom lens of Example 6 at the wide-angle end when focusing at infinity. FIG. 7 is a diagram showing longitudinal aberration at the wide-angle end of the zoom lens of Example 6 when focusing at infinity. FIG. 12 is a diagram showing longitudinal aberration of the zoom lens of Example 6 at an intermediate focal length state when focusing at infinity. FIG. 13 is a diagram showing longitudinal aberration at the telephoto end when the zoom lens of Example 6 is focused on an object at infinity. FIG. 13 is a diagram illustrating an optical configuration of a zoom lens according to a seventh embodiment at a wide-angle end when focused on infinity. FIG. 13 is a diagram showing longitudinal aberration at the wide-angle end when the zoom lens of Example 7 is focused on an object at infinity. FIG. 13 is a diagram showing longitudinal aberration of the zoom lens of Example 7 in a middle focal length state when focused on infinity. FIG. 13 is a diagram showing longitudinal aberration at the telephoto end when the zoom lens of Example 7 is focused on infinity. FIG. 7 is a diagram schematically showing the optical configuration of the zoom lens of Example 8 at the wide-angle end when focusing at infinity. FIG. 9 is a diagram showing longitudinal aberration at the wide-angle end of the zoom lens of Example 8 when focusing at infinity. FIG. 12 is a diagram showing longitudinal aberration of the zoom lens of Example 8 at an intermediate focal length state when focusing at infinity. FIG. 23 is a diagram showing longitudinal aberration at the telephoto end when the zoom lens of Example 8 is focused on infinity. 1 is a diagram schematically showing an example of the configuration of an imaging device according to an embodiment of the present invention.

DESCRIPTION OF THE PREFERRED EMBODIMENTS An embodiment of a zoom lens and an imaging device according to an embodiment of the present invention will be described below. More specifically, the present embodiment relates to a zoom lens and an imaging device suitable for an imaging device using a solid-state imaging device (CCD, CMOS, etc.) such as a digital still camera and a digital video camera. However, the zoom lens and imaging device described below are one embodiment of the zoom lens and imaging device according to the present invention, and the zoom lens and imaging device according to the present invention are not limited to the following embodiments. Note that in this specification, "in order" means arranged adjacently unless otherwise specified.

1. Zoom lens 1-1. Optical Configuration A zoom lens according to an embodiment of the present invention includes, in order from the object side, a front group having a negative refractive power and a rear group having a positive refractive power. A zoom lens according to an embodiment of the present invention may include only a front group and a rear group. The front group is a set of multiple lens groups on the object side that have negative refractive power as a whole, and the rear group is a set of multiple lens groups on the image side that have positive refractive power as a whole. is a set of lens groups having . If there are multiple combinations of front and rear groups under the above conditions, the optical axis of the front group, the lens group closest to the image plane, and the lens group closest to the object side of the rear group at the wide-angle end of the zoom lens. The set on the object side where the upper interval is widest is defined as the front group, and the set on the image plane side is defined as the rear group.

In this specification, a "lens group" includes one or more lenses. A "lens group" is one lens or a group of two or more lenses in which the distance between adjacent lens groups changes when changing the magnification between the wide-angle end and the telephoto end. When the lens group includes a plurality of lenses, the plurality of lenses maintain a relative positional relationship during zooming between the wide-angle end and the telephoto end. The lens group may be configured to be movable on the optical axis or may be fixed.

In this specification, a "composite lens group" is a collection of lenses determined according to their position on the optical axis and their overall refractive power. A composite lens group is composed of one or more lens groups. When a composite lens group is composed of two or more lens groups, each lens group can move independently along the optical axis.

A lens group may have one or more subgroups. A subgroup is made up of one or more lenses in a lens group. When a subgroup is made up of two or more lenses, it is made up of two or more lenses arranged in succession along the optical axis. The subgroup is fixed within the lens group, i.e., the subgroup is configured so that it can move on the optical axis with the lens group, but cannot move on the optical axis independently within the lens group. A subgroup can be identified as a lens or a set of two or more lenses that achieves a particular optical characteristic, such as the refractive power of the entire subgroup, from the lenses in the lens group.

The zoom lens may also have a cemented lens. The number of lenses in a cemented lens is the number of lenses that are cemented together. An example of a cemented lens is a cemented lens in which multiple lenses are integrated together with no air gap between them. Another example of a cemented lens is a cemented lens in which multiple lenses are integrated together and bonded together with a very thin adhesive that has a thickness that does not substantially affect the optical performance. In this case, the layer of adhesive is not counted as a lens. For example, a cemented lens in which two lenses are bonded together with a layer of adhesive is counted as two lenses.

Further, the lens included in the zoom lens may include a compound lens in which one lens and resin are integrated. For example, a compound lens in which one lens and resin are integrated is counted as one lens.

(1) Front group The front group has negative refractive power as a whole. The front group includes, as a lens group and a composite lens group, in order from the object side, only a lens group G1 having a positive refractive power and a composite lens group Gn having a negative refractive power. It is preferable to arrange the lens group G1 having a positive refractive power closest to the object side from the viewpoint of providing a telephoto type refractive power arrangement and shortening the total optical length of the zoom lens compared to the focal length.

(2) Lens group G1
Lens group G1 has positive refractive power. The lens group G1 includes, in order from the object side, a sub group G1a that is disposed closest to the object side and has a positive refractive power, and a sub group G1b that is disposed at an air interval from the sub group G1a. You may do so. This configuration is preferable from the viewpoint of reducing the diameter of the sub group G1b and from the viewpoint of reducing the weight of the lens group G1, which has the largest proportion of lens weight among the lens groups included in the zoom lens.

Sub group G1a may include one or more lenses having positive refractive power. The sub group G1a may include two or more lenses having positive refractive power. It is preferable for the subgroup G1a to have two or less lenses having positive refractive power from the viewpoint of reducing the weight of the subgroup G1a and from the viewpoint of efficiently and easily lowering the height of the light rays incident on the subgroup G1b. Further, it is preferable that the sub group G1a does not include a lens having negative refractive power from the viewpoint of reducing the weight of the lens group G1.

The subgroup G1b may have one or more lenses with positive refractive power and one or more lenses with negative refractive power. It is preferable that the subgroup G1b has a lens with positive refractive power and a lens with negative refractive power from the viewpoint of good and easy correction of spherical aberration and chromatic aberration. It is preferable that one of the lenses with positive refractive power in the subgroup G1b is arranged on the most object side of the subgroup G1b from the viewpoint of reducing the weight of the lens group G1. In addition, the lens with negative refractive power in the subgroup G1b tends to use a material with a larger specific gravity than the lens with positive refractive power in the subgroup G1a or the lens with positive refractive power in the subgroup G1b. Therefore, it is preferable that the air gap between the subgroup G1a and the subgroup G1b is the maximum air gap in the lens group G1 from the viewpoint of reducing the weight of the lens group G1.

It is preferable for lens group G1 to have one or more lenses with negative refractive power from the viewpoint of good and easy correction of spherical aberration and chromatic aberration. Lens group G1 may have a plurality of lenses with negative refractive power that satisfy the formula (7) described below. The lens with negative refractive power included in lens group G1 may be a lens with negative refractive power included in subgroup G1b.

(3) Composite lens group Gn
The composite lens group Gn has negative refractive power as a whole. The composition of the composite lens group Gn may be appropriately determined within a range in which the entire lens group has negative refractive power. The composite lens group Gn has one or more lens groups, and may be composed of only one lens group, or may be composed of a plurality of lens groups. For example, the composite lens group Gn may include one or more lens groups having negative refractive power. The composite lens group Gn is composed of a plurality of lens groups. By changing the distance between adjacent lens groups during zooming between the wide-angle end and the telephoto end, spherical aberration and field curvature can be suppressed over the entire zoom range. It is also preferable from the viewpoint of easy correction. When the composite lens group Gn is composed of a plurality of lens groups, the plurality of lens groups may include at least one lens group having positive refractive power.

It is preferable that the composite lens group Gn has at least one lens with negative refractive power, and it is more preferable that the composite lens group Gn has two or more lenses with negative refractive power. This configuration is preferable from the viewpoint of giving the composite lens group Gn a strong negative refractive power and obtaining a zoom lens with a high variable magnification.

Furthermore, it is preferable that the composite lens group Gn has at least one lens with positive refractive power. It is preferable that the composite lens group Gn has two or more lenses with negative refractive power and one or more lenses with positive refractive power, from the viewpoint of correcting various aberrations well and achieving both high zoom ratio and high performance. In this case, it is preferable that the lens closest to the object side in the composite lens group Gn is a lens with positive refractive power, since this can lower the height of the light rays incident on the lens group arranged on the image plane side of the composite lens group Gn, thereby contributing to the miniaturization and weight reduction of the entire zoom lens.

(4) Rear group The rear group has positive refractive power as a whole. The rear group includes, in order from the object side, a composite lens group Gp having a positive refractive power and a lens group Gf having a negative refractive power. The rear group further includes a lens group Gr having a negative refractive power closer to the image plane than the lens group Gf. Such a configuration is preferable from the viewpoint of easily realizing a zoom lens with a short overall length, since the telephoto type refractive power arrangement can be made stronger.

The rear group may be composed of only the aforementioned composite lens group Gp, lens group Gf, and lens group Gr, or may further include other lens groups. The rear group may have one or more lens groups between lens group Gf and lens group Gr. Alternatively, the rear group may have one or more lens groups on the image surface side of lens group Gr.

(5) Composite Lens Group Gp
The composite lens group Gp has a positive refractive power as a whole. The composite lens group Gp has one or more lens groups, and may be composed of only one lens group, or may have multiple lens groups. For example, the composite lens group Gp may have one or more lens groups having positive refractive power. When the composite lens group Gp is composed of multiple lens groups, the multiple lens groups may have at least one lens group having negative refractive power.

When the composite lens group Gp is composed of a plurality of lens groups, it is preferable to have a lens group having a positive refractive power closest to the object side. In addition, the composite lens group Gp includes, in order from the object side, a lens having a first positive refractive power, a lens having a second positive refractive power, a lens having a third positive refractive power, and a first lens having a positive refractive power. It is more preferable to have a lens with negative refractive power. Such a configuration is preferable from the viewpoint of strengthening the telephoto type refractive power arrangement and realizing miniaturization of the lens group and the aperture diameter arranged closer to the image plane than the composite lens group Gp.

The composite lens group Gp preferably includes an anti-shake group Gv that has negative refractive power and moves in a direction perpendicular to the optical axis to correct image blur. The anti-vibration group Gv is a collection of one or more lenses. The anti-vibration group Gv is arranged closer to the image plane than the first lens having negative refractive power, so that the angle of incidence of the axial light beam incident on the anti-vibration group Gv becomes gentler, and eccentricity during image stabilization is reduced. This is preferable from the viewpoint of suppressing the occurrence of aberrations. In the composite lens group Gp, it is preferable that the vibration isolation group Gv be arranged closer to the image plane side from the viewpoint of realizing a smaller diameter of the vibration isolation group Gv.

The configuration of the anti-vibration group Gv can be appropriately determined within a range in which the entire lens has a negative refractive power. It is preferable that the anti-vibration group Gv is composed of two or less lenses from the viewpoint of realizing miniaturization of the anti-vibration drive mechanism. In addition, the fact that the anti-vibration group Gv is composed of only a cemented lens consisting of one lens with positive refractive power and one lens with negative refractive power reduces chromatic aberration during anti-vibration. This is preferable from the viewpoint of good correction.

(6) Lens group Gf
The lens group Gf is disposed at a position adjacent to the image surface side of the composite lens group Gp. Such a configuration is preferable from the viewpoint of realizing the miniaturization and weight reduction of the zoom lens and the miniaturization of the focus mechanism. The lens group Gf has a negative refractive power as a whole and has at least one lens having a negative refractive power. The configuration of the lens group Gf can be appropriately determined within the range of having a negative refractive power as a whole and having at least one lens having a negative refractive power. For example, it is preferable that the lens group Gf further has a lens having a positive refractive power from the viewpoint of suppressing aberration fluctuations over the entire object distance. In addition, it is preferable that the lens group Gf has, in order from the object side, a lens having a positive refractive power and a lens having a negative refractive power from the viewpoint of realizing the miniaturization and weight reduction of the lens group Gf.

(7) Lens group Gr
Lens group Gr is arranged on the image plane side of lens group Gf, and has negative refractive power. In the case where a plurality of lens groups having a negative refractive index are arranged on the image plane side of the lens group Gf, the lens group Gr is a plurality of lens groups having a negative refractive index arranged on the image plane side of the lens group Gf. Among them, this lens group has the strongest negative refractive power. The configuration of the lens group Gr can be appropriately determined within a range in which the entire lens group has negative refractive power. For example, the lens group Gr may include one or more lenses having negative refractive power. In addition, the fact that the lens group Gr includes two or more lenses with negative refractive power and one or more lenses with positive refractive power is advantageous from the viewpoint of strengthening the telephoto type structure and reducing the overall length of the zoom lens. This is preferable from the viewpoint of realizing both shortening and high performance.

(8) Aperture diaphragm In the zoom lens, the aperture diaphragm may be disposed in the front group, may be disposed in the rear group, or may be disposed between the front group and the rear group. Moreover, it is preferable that the aperture diaphragm is disposed in the rear group, and may be disposed, for example, in the composite lens group Gp, or may be disposed between the composite lens group Gp and the lens group Gf. Disposing the aperture diaphragm in the rear group is preferable from the viewpoint of realizing a compact aperture diaphragm unit. Disposing the aperture diaphragm in the composite lens group Gp or between the composite lens group Gp and the lens group Gf is preferable from the viewpoint of realizing a compact aperture diaphragm unit, since the diameter of the incident light beam becomes small.

1-2. Operation (1) Magnification change In the zoom lens, the distance between adjacent lens groups on the optical axis changes when the magnification is changed between the wide-angle end and the telephoto end. The distance between each lens group on the optical axis changes when the magnification is changed between the wide-angle end and the telephoto end, and some lens groups may be fixed in the optical axis direction (do not move on the optical axis). The lens group G1 is the heaviest lens group among the lens groups of the zoom lens. Therefore, in order to move the heavy lens group to a predetermined position with high accuracy when the magnification is changed, the load applied to the member for driving the lens group G1 is also large, and the structure for driving the lens group G1 may also become large. From the viewpoint of realizing a compact zoom lens, it is preferable that the lens group G1 is fixed when the magnification is changed between the wide-angle end and the telephoto end.

Further, it is preferable that at least one of the one or more lens groups included in the composite lens group Gn moves on the optical axis toward the image plane side during zooming from the wide-angle end to the telephoto end. When the composite lens group Gn has a plurality of lens groups, all the lens groups may move during zooming. It is preferable for the lens groups of the composite lens group Gn to move in this manner during zooming from the viewpoint of reducing the diameter of the lens groups after the composite lens group Gn at the telephoto end.

When changing the magnification between the wide-angle end and the telephoto end, it is preferable that the distance between the composite lens group Gp and the lens group Gf on the optical axis be widened at the middle of the zoom. It is preferable to move in this manner from the viewpoint that it becomes easy to satisfactorily correct the curvature of field over the entire zoom range.

When changing magnification from the wide-angle end to the telephoto end, the lens group Gr moves along the optical axis toward the object side. When changing magnification from the wide-angle end to the telephoto end, the lens group Gr having negative refractive power moves along the optical axis toward the object side, which is preferable from the perspective of realizing a zoom lens with a high magnification ratio, since this allows for a larger magnification ratio.

(2) Focusing During focusing, the lens group Gf moves on the optical axis. During focusing from an infinity focused state to a minimum distance focused state, it is preferable that the lens group Gf moves toward the image surface along the optical axis. This configuration is preferable in a zoom lens in which the focus group is located closer to the image surface than the aperture diaphragm, from the viewpoint of suppressing fluctuations in the aperture diameter when moving from an infinity focused state to a minimum distance focused state.

The focus group in the zoom lens may further include lens groups other than lens group Gf. In a zoom lens, for example, one or more lens groups having positive or negative refractive power, which are arranged on the image plane side of the lens group Gf, are moved on the optical axis with a movement trajectory different from that of the lens group Gf. It is also possible to use a configuration in which focusing is performed using . In this way, the so-called floating focus method may be adopted for the zoom lens. Such a configuration is preferable from the viewpoint of better correcting spherical aberration and field curvature over the entire object distance.

1-3. Formula Expressing Conditions of Zoom Lens It is desirable that the zoom lens according to the present embodiment employs the above-described configuration and satisfies at least one or more of the following formulas.

1-3-1. Formula (1)
−0.90≦fr/ft≦−0.03 (1)
however,
fr: focal length of lens group Gr ft: focal length at telephoto end of zoom lens when focused at infinity

Equation (1) is a formula for appropriately setting the ratio between the focal length of the lens group Gr and the focal length of the zoom lens at the telephoto end when focusing on infinity. Specifically, equation (1) is a formula for appropriately setting the focal length of the lens group Gr relative to the focal length of the zoom lens at the telephoto end when focusing on infinity. Satisfying equation (1) is preferable from the standpoint of ensuring a telephoto type refractive power arrangement and easily realizing the miniaturization of the entire zoom lens.

When fr/ft is below the lower limit of formula (1), the telephoto type refractive power arrangement becomes weak, and it may be difficult to achieve a small overall length. For example, if the positive refractive power of lens group G1 is strengthened to ensure a telephoto configuration, it may be difficult to effectively correct chromatic aberration in particular. Also, when fr/ft is above the upper limit of formula (1), the telephoto type refractive power arrangement becomes too strong, and it may be difficult to effectively correct strong curvature of field in the over direction.

From the viewpoint of realizing miniaturization of the total length, fr/ft is more preferably -0.80 or more, more preferably -0.75 or more, and more preferably -0.70 or more. , more preferably -0.65 or more, more preferably -0.60 or more, more preferably -0.55 or more, more preferably -0.50 or more. Furthermore, from the viewpoint of satisfactorily correcting strong overdirection field curvature, fr/ft is more preferably -0.08 or less, more preferably -0.13 or less, and -0.18 It is more preferably below, more preferably -0.23 or less, even more preferably -0.28 or less.

1-3-2. Equation (2)
1.01≦βrt/βrw≦1.50 (2)
however,
βrt: lateral magnification at the telephoto end when the lens group Gr is focused at infinity βrw: lateral magnification at the wide-angle end when the lens group Gr is focused at infinity

Equation (2) is a formula for appropriately setting the ratio between the lateral magnification at the telephoto end when the lens group Gr is focused at infinity and the lateral magnification at the wide-angle end. Specifically, equation (2) is a formula for appropriately setting the lateral magnification at the telephoto end when the lens group Gr is focused at infinity relative to the lateral magnification at the wide-angle end when the lens group Gr is focused at infinity. Satisfying equation (2) is preferable from the viewpoint of achieving both high performance and high magnification by appropriately setting the zoom ratio of the lens group Gr.

If βrt/βrw falls below the lower limit of formula (2), it may become impossible to change the magnification with the lens group Gr, making it difficult to achieve a high variable magnification. To achieve a high variable magnification, the amount of movement of at least one of the lens groups in the composite lens group Gn becomes large, making it difficult to reduce the overall length of the zoom lens. Also, if βrt/βrw exceeds the upper limit of formula (2), the burden of changing the magnification of the lens group Gr becomes too large, making it difficult to satisfactorily correct the curvature of field.

From the viewpoint of achieving a high zoom ratio, βrt/βrw is preferably 1.03 or more, more preferably 1.05 or more, and even more preferably 1.07 or more. From the viewpoint of satisfactorily correcting the field curvature, βrt/βrw is preferably 1.40 or less, more preferably 1.30 or less, and even more preferably 1.25 or less.

1-3-3. Equation (3)
Xp/(-Xn)≦1.0 (3)
however,
Xn: the movement amount of the lens group having negative refractive power in the composite lens group Gn from the wide-angle end to the telephoto end, and Xp: the movement amount of the lens group having positive refractive power in the composite lens group Gp from the wide-angle end to the telephoto end. amount of movement

The formula (3) is a formula for appropriately setting the ratio of the movement amount of the lens group having a positive refractive power of the composite lens group Gp to the movement amount of the lens group having a negative refractive power of the composite lens group Gn when the magnification is changed from the wide-angle end to the telephoto end. When the composite lens group Gn has a plurality of lens groups having negative refractive power, it is sufficient that one or more lens groups having negative refractive power satisfy the formula (14). When the composite lens group Gp has a plurality of lens groups having positive refractive power, it is sufficient that one or more lens groups having positive refractive power satisfy the formula (3). Here, the sign of each movement amount is positive when the movement toward the object side on the optical axis is changed from the wide-angle end to the telephoto end. Satisfying the formula (3) is preferable from the viewpoint of making the diameter of the rear group small and realizing the weight reduction of the entire zoom lens.

When Xp/(-Xn) exceeds the upper limit of formula (3), the amount of movement of the lens group with positive refractive power in the composite lens group Gp becomes too large, which may make it difficult to achieve a small diameter for the rear group at the telephoto end.

From the viewpoint of realizing a smaller diameter of the rear group, Xp/(-Xn) is more preferably 0.90 or less, more preferably 0.80 or less, and even more preferably 0.75 or less. It is preferably 0.70 or less, and more preferably 0.70 or less. The lower limit of Xp/(-Xn) can be appropriately determined within the range in which the effects of the present invention can be obtained. For example, Xp/(-Xn) is more preferably 0.10 or more, more preferably 0.15 or more, and even more preferably 0.20 or more. If Xp/(-Xn) is below the lower limit, the amount of movement of the lens group having negative refractive power in the composite lens group Gn becomes too large, and the load applied to the mechanical members for driving the composite lens group Gn is also large. It may happen. Therefore, it may be difficult to achieve a good operating feel during zooming.

1-3-4. Equation (4)
0.65≦|fv|/fpt≦2.00 (4)
however,
fv: focal length of the image stabilization group Gv fpt: focal length at the telephoto end of the composite lens group Gp

Equation (4) is an equation for appropriately setting the ratio between the refractive power of the vibration reduction group Gv and the refractive power of the composite lens group Gp at the telephoto end. Specifically, equation (4) is an equation for appropriately setting the absolute value of the focal length of the vibration reduction group Gv relative to the focal length of the composite lens group Gp at the telephoto end. Satisfying equation (4) is preferable from the standpoint of suppressing aberrations that occur during vibration reduction while controlling the drive amount of the vibration reduction group Gv during vibration reduction within an appropriate range.

When |fv|/fpt is below the lower limit of formula (4), the drive amount of the vibration-reduction group Gv for correcting image blur is small, which is advantageous for miniaturizing the vibration-reduction drive mechanism, but it may be difficult to satisfactorily correct spherical aberration and astigmatism during vibration reduction. Also, when |fv|/fpt is above the upper limit of formula (4), the drive amount of the vibration-reduction group Gv for correcting image blur is large, which increases the size of the vibration-reduction drive mechanism and may make it difficult to achieve a compact zoom lens as a whole.

From the viewpoint of properly correcting spherical aberration and astigmatism during image stabilization, |fv|/fpt is more preferably 0.70 or more, more preferably 0.80 or more, and 0.90 It is more preferably 1.00 or more, and more preferably 1.00 or more. Further, from the viewpoint of realizing miniaturization of the entire zoom lens, |fv|/fpt is more preferably 1.90 or less, more preferably 1.80 or less, and more preferably 1.70 or less. It is more preferable that it is 1.65 or less.

1-3-5. Formula (5)
0.35≦Lt/ft≦0.70 (5)
however,
Lt: Total optical length of the zoom lens at the telephoto end when focusing on infinity ft: Focal length of the zoom lens at the telephoto end when focusing on infinity

Equation (5) is a formula for appropriately setting the ratio between the total optical length of the zoom lens at the telephoto end when focusing on infinity and the focal length of the zoom lens at the telephoto end when focusing on infinity. Specifically, equation (5) is a formula for appropriately setting the total optical length of the zoom lens at the telephoto end when focusing on infinity relative to the focal length of the zoom lens at the telephoto end when focusing on infinity. Specifically, "total optical length" is the total length on the optical axis from the object-side lens surface of the lens closest to the object among the lenses that make up the zoom lens to the image plane. Satisfying equation (5) is preferable from the perspective of realizing a small, lightweight zoom lens with a short optical length relative to the focal length.

If Lt/ft is less than the lower limit of equation (5), the total optical length of the zoom lens may become too short relative to the focal length, making it difficult to satisfactorily correct various aberrations. Furthermore, the sensitivity of each lens to errors increases, and the optical performance may deteriorate too much due to manufacturing errors. When Lt/ft exceeds the upper limit of equation (5), the amount of movement of each lens group during zooming increases in order to obtain a predetermined zoom ratio, and the amount of movement of each lens group increases along the optical axis. This may lead to an increase in the size of the variable power drive mechanism, making it difficult to realize a desired compact and lightweight zoom lens.

From the viewpoint of correcting various aberrations well and maintaining optical performance, Lt/ft is more preferably 0.38 or more, more preferably 0.41 or more, and more preferably 0.44 or more. is more preferable, and more preferably 0.47 or more. Further, from the viewpoint of realizing a compact and lightweight zoom lens, Lt/ft is more preferably 0.68 or less, more preferably 0.66 or less, and even more preferably 0.64 or less. It is preferably 0.62 or less, more preferably 0.60 or less.

1-3-6. Equation (6)
5.0≦|{1−(βft) ² }×(βcrt) ² |≦13.0 (6)
however,
βft: lateral magnification at the telephoto end when the lens group Gf is focused at infinity βcrt: lateral magnification at the telephoto end of all lens groups on the image side of the lens group Gf when focused at infinity

Equation (6) is an equation for appropriately setting the relationship |{1-(βft)2}×(βcrt) ² | between the lateral magnification of the lens group Gf at the telephoto end when focused at infinity and the lateral magnifications of all lens groups on the image plane side of the lens group ^Gf at the telephoto end when focused at infinity. Satisfying equation (6) is preferable from the viewpoint of controlling the focus position sensitivity within an appropriate range when the lens group Gf is used as the focus group.

If |{1-(βft) ² }×(βcrt) ² | is below the lower limit of formula (6), the focus movement amount becomes too large, which may lead to an increase in the size of the focus actuator. Also, if |{1-(βft) ² }×(βcrt) ² | is above the upper limit of formula (6), the focus movement amount per movement amount of the focus group, i.e., the focus position sensitivity, becomes too large, which may make focusing control difficult since the required focusing drive accuracy becomes high.

From the viewpoint of preventing the focus actuator from increasing in size, |{1-(βft) ² }×(βcrt) ² | is more preferably 5.4 or more, more preferably 5.8 or more, and 6 It is more preferably .2 or more, more preferably 6.6 or more, and even more preferably 7.0 or more. Further, |{1-(βft) ² }×(βcrt) ² | is more preferably 12.5 or less, more preferably 12.0 or less, and more preferably 11.5 or less. It is preferably 11.0 or less, more preferably 10.5 or less.

1-3-7. Equation (7)
−0.012≦ΔPgF1≦−0.001 (7)
however,
ΔPgF1: Anomalous dispersion of at least one lens having negative refractive power included in the lens group G1

Formula (7) is a formula for appropriately setting the anomalous dispersion ΔPgF1 at the g-line and F-line of at least one lens having a negative refractive power in the lens group G1. When the lens group G1 includes multiple lenses having a negative refractive power, at least one lens having a negative refractive power only needs to satisfy formula (7). Here, "anomalous dispersion" represents the deviation of the partial dispersion ratio from a reference line when a straight line passing through the coordinates of glass material C7 with a partial dispersion ratio of 0.5393 and νd of 60.49 and the coordinates of glass material F2 with a partial dispersion ratio of 0.5829 and νd of 36.30 is used as the reference line in a coordinate system with the partial dispersion ratio of the g-line and F-line on the vertical axis and the Abbe number νd for the d-line on the horizontal axis.

In general, in zoom lenses, chromatic aberration is corrected by using a low-dispersion glass material for lenses with positive refractive power, and using a high-dispersion glass material for lenses with negative refractive power. There is. However, when the reference line is a straight line passing through the coordinates of the partial dispersion ratio of glass materials C7 and F2 and the Abbe number (νd) for the d-line, the deviation of the partial dispersion ratio of the glass material on the low dispersion side from the reference line is positive. Located in the direction. In this case, in order to perform good chromatic aberration correction even on the short wavelength side of the visible light range, it is necessary to use a lens whose deviation from the reference line of the partial dispersion ratio is in the negative direction for the glass material on the high dispersion side. Therefore, it is preferable to satisfy Equation (7) from the viewpoint of easily realizing a zoom lens having high optical performance in which lateral chromatic aberration is well corrected, especially at the telephoto end.

When ΔPgF1 is below the lower limit of formula (7), excessive chromatic aberration correction may cause the curvature of the lens with negative refractive power in lens group G1 to become too strong. When the curvature of the lens with negative refractive power in lens group G1 becomes strong, it has a large impact on the lens weight, and it may become difficult to realize a lightweight zoom lens. Furthermore, when ΔPgF1 exceeds the upper limit of formula (7), chromatic aberration correction on the short wavelength side at the telephoto end becomes insufficient, and it may become difficult to realize a zoom lens with high optical performance.

From the viewpoint of realizing a lightweight zoom lens, ΔPgF1 is preferably -0.010 or more, more preferably -0.009 or more, more preferably -0.008 or more, and more preferably -0.007 or more. Furthermore, from the viewpoint of realizing a zoom lens with high optical performance, ΔPgF1 is more preferably -0.002 or less, more preferably -0.003 or less, more preferably -0.004 or less, and more preferably -0.005 or less.

1-3-8. Equation (8)
0.015≦ΔPgFr≦0.050 (8)
however,
ΔPgFr: Anomalous dispersion of at least one lens having negative refractive power included in the lens group Gr

Equation (8) is a formula for appropriately setting the anomalous dispersion ΔPgFr at the g-line and F-line of at least one lens having negative refractive power included in the lens group Gr. When the lens group Gr includes multiple lenses having negative refractive power, it is sufficient that at least one lens having negative refractive power satisfies equation (8).

Generally, in telephoto zoom lenses, lateral chromatic aberration on the short wavelength side tends to occur in the under direction at the telephoto end. Therefore, satisfying Expression (8) is preferable from the viewpoint of correcting the lateral chromatic aberration of magnification on the short wavelength side due to the lens group G1 by causing it to occur in the over direction and canceling it out. When the lens group G1 causes lateral chromatic aberration on the short wavelength side to occur in the over direction, longitudinal chromatic aberration on the short wavelength side will occur in the under direction. Therefore, it is preferable to satisfy Equation (8) from the viewpoint of satisfactorily correcting the longitudinal chromatic aberration in the under direction on the short wavelength side. Therefore, it is preferable to satisfy the expression (8) from the viewpoint of easily realizing a zoom lens having high optical performance in which chromatic aberration is well corrected.

If ΔPgFr is below the lower limit of formula (8), the correction of axial chromatic aberration at the telephoto end will be insufficient, and it may be difficult to realize a zoom lens with high optical performance. Also, if ΔPgFr is above the upper limit of formula (8), it may be difficult to achieve a good balance between axial chromatic aberration and lateral chromatic aberration.

From the viewpoint of realizing a zoom lens having high optical performance, ΔPgFr is more preferably 0.017 or more, more preferably 0.019 or more, more preferably 0.021 or more, and even more preferably 0.023 or more. Furthermore, from the viewpoint of realizing a good balance between axial chromatic aberration and lateral chromatic aberration, ΔPgFr is more preferably 0.045 or less, more preferably 0.040 or less, and even more preferably 0.035 or less.

1-3-9. Equation (9)
0.05≦fpt/ft≦0.20 (9)
however,
fpt: focal length at the telephoto end of the composite lens group Gp ft: focal length at the telephoto end of the zoom lens when focused at infinity

Equation (9) is an equation for appropriately setting the ratio between the focal length of the composite lens group Gp at the telephoto end and the focal length of the zoom lens at the telephoto end when focusing on infinity. Specifically, equation (9) is an equation for appropriately setting the focal length of the composite lens group Gp at the telephoto end relative to the focal length of the zoom lens at the telephoto end when focusing on infinity. Satisfying equation (9) is preferable from the standpoint of realizing a compact, lightweight zoom lens with a short overall length that easily corrects various aberrations.

If fpt/ft is less than the lower limit of equation (9), the refractive power of the composite lens group Gp will become too strong, making it difficult to properly correct spherical aberration and comatic aberration, making it difficult to use a zoom lens with high optical performance. This may be difficult to achieve. Furthermore, if fpt/ft exceeds the upper limit of equation (9), it may be difficult to shorten the total length of the zoom lens at the telephoto end. In order to realize a compact zoom lens with a desired short overall length, it is necessary to increase the positive refractive power of the lens group G1, which may make it particularly difficult to correct chromatic aberrations well.

From the viewpoint of realizing a zoom lens with high optical performance, fpt/ft is more preferably 0.06 or more, more preferably 0.07 or more, and more preferably 0.08 or more. , more preferably 0.09 or more. Further, from the viewpoint of shortening the total length of the zoom lens at the telephoto end, fpt/ft is more preferably 0.18 or less, more preferably 0.16 or less, and more preferably 0.14 or less. More preferred.

1-3-10. Equation (10)
0.40≦f1/fw≦3.00 (10)
however,
f1: focal length of lens group G1 fw: focal length at the wide-angle end of the zoom lens when focused at infinity

Equation (10) is an equation for appropriately setting the ratio between the focal length of lens group G1 and the focal length at the wide-angle end when the zoom lens is focused at infinity. Specifically, equation (10) is an equation for appropriately setting the focal length of lens group G1 relative to the focal length at the wide-angle end when the zoom lens is focused at infinity. Satisfying equation (10) is preferable from the perspective of realizing a zoom lens with high optical performance while realizing a compact zoom lens at the wide-angle end.

When f1/fw is less than the lower limit of equation (10), the refractive power of the lens group G1 becomes too large, and it may become difficult to satisfactorily correct the curvature of field at the wide-angle end. Furthermore, when f1/fw exceeds the upper limit of equation (10), the refractive power of the lens group G1 becomes too small, and it may become difficult to shorten the total optical length at the wide-angle end.

From the viewpoint of effectively correcting the curvature of field at the wide-angle end, f1/fw is preferably 0.50 or more, more preferably 0.60 or more, more preferably 0.70 or more, more preferably 0.80 or more, and more preferably 0.90 or more. Also, from the viewpoint of shortening the total optical length at the wide-angle end, f1/fw is more preferably 2.70 or less, more preferably 2.40 or less, more preferably 2.10 or less, and more preferably 1.90 or less.

1-3-11. Equation (11)
0.28≦f1/ft≦0.55 (11)
however,
f1: focal length of lens group G1 ft: focal length at telephoto end of zoom lens when focused at infinity

Equation (11) is an equation for appropriately setting the ratio between the focal length of lens group G1 and the focal length at the telephoto end of the zoom lens when focusing on infinity. Specifically, it is an equation for appropriately setting the focal length of lens group G1 relative to the focal length at the telephoto end of the zoom lens when focusing on infinity. Satisfying equation (11) is preferable from the standpoint of realizing a compact zoom lens at the telephoto end and realizing a zoom lens with high optical performance.

When f1/ft is less than the lower limit of equation (11), the refractive power of the lens group G1 becomes too large, and it may become difficult to satisfactorily correct spherical aberration at the telephoto end. Furthermore, when f1/ft exceeds the upper limit of equation (11), the refractive power of the lens group G1 becomes too small, and it may become difficult to shorten the total optical length at the telephoto end.

From the viewpoint of properly correcting spherical aberration at the telephoto end, f1/ft is more preferably 0.30 or more, more preferably 0.32 or more, and even more preferably 0.34 or more. . Further, from the viewpoint of shortening the total optical length at the telephoto end, f1/ft is more preferably 0.52 or less, more preferably 0.49 or less, and even more preferably 0.46 or less. It is preferably 0.44 or less, and more preferably 0.44 or less.

1-3-12. Equation (12)
0.50≦BFw/Yw≦4.50 (12)
BFw: Distance on the optical axis from the lens surface closest to the image plane to the image plane at the wide-angle end when the zoom lens is focused at infinity Yw: Maximum image height at the wide-angle end when the zoom lens is focused at infinity

Equation (12) is an equation for appropriately setting the ratio between the back focus and the maximum image height at the wide-angle end when the zoom lens is focused at infinity. Specifically, Equation (12) is expressed as: This is a formula for appropriately setting the distance on the optical axis from to the image plane. If another optical element is interposed between the lens surface closest to the image plane and the image plane, the optical distance of the other optical element is the air equivalent distance on the optical axis of the optical element. . Examples of the other optical element include a glass flat member having parallel surfaces, a filter, and the like. Examples of the flat glass member include dummy glass and cover glass. It is preferable to satisfy formula (12) from the viewpoint of ensuring a back focus suitable for exchanging zoom lenses at the wide-angle end and from the viewpoint of realizing a compact zoom lens.

If BFw/Yw is below the lower limit of equation (12), the back focus becomes too short, and the inclination angle of the light incident on the image sensor with respect to the optical axis may become too large. To reduce the inclination angle, the exit pupil diameter must be increased, which may make it difficult to reduce the diameter of the lens group located closest to the image plane in the zoom lens. Also, if BFw/Yw is above the upper limit of equation (12), the back focus becomes too long, and it may make it difficult to reduce the size of the zoom lens at the wide-angle end.

From the viewpoint of reducing the diameter of the lens group located closest to the image plane of the zoom lens, BFw/Yw is more preferably 0.70 or more, more preferably 0.75 or more, and 0.70 or more. It is more preferably 80 or more, more preferably 0.85 or more, and even more preferably 0.90 or more. Further, from the viewpoint of realizing miniaturization of the zoom lens at the wide-angle end, BFw/Yw is more preferably 4.20 or less, more preferably 3.90 or less, and 3.60 or less. is more preferable, and more preferably 3.30 or less.

2. Imaging Device Next, an imaging device according to an embodiment of the present invention will be described. The imaging device includes the zoom lens according to the embodiment described above, and an imaging element that is provided on the image plane side of the zoom lens and converts an optical image formed by the zoom lens into an electrical signal.

Here, the imaging element is not limited, and solid-state imaging elements such as CCD (Charge Coupled Device) sensors and CMOS (Complementary Metal Oxide Semiconductor) sensors can be used as the imaging element, and silver halide film can also be used. The imaging device according to this embodiment is suitable for imaging devices using the above-mentioned solid-state imaging elements, such as digital cameras and video cameras. The imaging device may be a fixed-lens imaging device in which the lens is fixed to the housing, or a lens-interchangeable imaging device such as a single-lens reflex camera or a mirrorless single-lens camera. In particular, the zoom lens according to this embodiment can ensure a back focus suitable for an interchangeable lens system. Therefore, it is suitable for imaging devices such as single-lens reflex cameras equipped with an optical finder, a phase difference sensor, and a reflex mirror for branching light to these sensors.

Fig. 33 is a diagram showing a schematic example of the configuration of an imaging device according to this embodiment. As shown in Fig. 33, a mirrorless single-lens camera 1 has a body 2 and a lens barrel 3 that is detachable from the body 2. The mirrorless single-lens camera 1 is one form of an imaging device.

The lens barrel 3 has a zoom lens 30. The zoom lens 30 includes a first lens group 31 , a second lens group 32 , a third lens group 33 , a fourth lens group 34 , and a fifth lens group 35 . The zoom lens 30 is configured to satisfy, for example, the above-mentioned equations (1) and (2). The first lens group 31 includes a first sub-a group 31a and a first sub-b group 31b. Note that a diaphragm 36 is arranged within the third lens group 33.

The first lens group 31 has a positive refractive power and corresponds to the aforementioned lens group G1. The second lens group 32 has a negative refractive power and corresponds to the aforementioned composite lens group Gn. The third lens group 33 has a positive refractive power and corresponds to the aforementioned composite lens group Gp. The fourth lens group 34 has a negative refractive power and corresponds to the aforementioned lens group Gf. The fifth lens group 35 has a negative refractive power and corresponds to the aforementioned lens group Gr. The first sub-a group 31a has a positive refractive power and corresponds to the aforementioned sub-group G1a. The first sub-b group 31b has a positive refractive power and corresponds to the aforementioned sub-group G1b. The first lens group 31 and the second lens group 32 correspond to the aforementioned front group. The third lens group 33, the fourth lens group 34, and the fifth lens group 35 correspond to the aforementioned rear group. The third lens group 33 corresponds to the aforementioned vibration-proof group.

The main body 2 has a CCD sensor 21 as an image sensor and a cover glass 22. The CCD sensor 21 is arranged in the main body 2 at a position where the optical axis OA of the zoom lens 30 in the lens barrel 3 mounted on the main body 2 is the central axis. Instead of the cover glass 22, the main body 2 may have a parallel flat plate having no substantial refractive power.

It is more preferable that the imaging device according to this embodiment has an image processing section that electrically processes the captured image data acquired by the imaging element to change the shape of the captured image, and an image correction data storage section that stores image correction data and an image correction program used to process the captured image data in the image processing section.

When a zoom lens is made smaller, distortion (curvature) of the captured image shape formed on the imaging plane is more likely to occur. In such cases, it is preferable to correct the distortion of the captured image shape. This correction can be performed, for example, by storing distortion correction data for correcting the distortion of the captured image shape in advance in an image correction data storage unit, and using the distortion correction data stored in the image correction data storage unit in the image processing unit. With such an imaging device, it is possible to further miniaturize the zoom lens, obtain a beautiful captured image, and miniaturize the entire imaging device.

Furthermore, in the imaging device according to this embodiment, it is preferable to have the image correction data storage unit store magnification chromatic aberration correction data in advance. It is also preferable that the image processing unit performs magnification chromatic aberration correction of the captured image using the magnification chromatic aberration correction data stored in the image correction data storage unit. By correcting the magnification chromatic aberration, i.e., color distortion aberration, with the image processing unit, it is possible to reduce the number of lenses that make up the zoom lens. Therefore, with such an imaging device, it is possible to further miniaturize the zoom lens, obtain a beautiful captured image, and miniaturize the entire imaging device.

The present invention is not limited to the above-described embodiments, and various modifications are possible within the scope of the claims. Embodiments obtained by appropriately combining the technical means disclosed in the different embodiments are also included in the technical scope of the present invention.

(summary)
A zoom lens according to a first aspect of the present invention has, in order from the object side, a front group having negative refractive power and a rear group having positive refractive power, the front group has, as lens groups and composite lens groups, only a lens group G1 having positive refractive power and a composite lens group Gn having negative refractive power, in that order from the object side, the rear group has, in order from the object side, a composite lens group Gp having positive refractive power and a lens group Gf having negative refractive power, the rear group further has a lens group Gr having negative refractive power on the image surface side of the lens group Gf, the composite lens group Gn has one or more lens groups, the composite lens group Gp has one or more lens groups, the distance on the optical axis between adjacent lens groups changes when zooming between the wide-angle end and the telephoto end, the lens group G1 is fixed, when zooming from the wide-angle end to the telephoto end, the lens group Gr moves on the optical axis toward the object side, and when focusing, the lens group Gf moves on the optical axis, and the zoom lens satisfies the following formula:
−0.90≦fr/ft≦−0.03 (1)
1.01≦βrt/βrw≦1.50 (2)
however,
fr: focal length of the lens group Gr; ft: focal length of the zoom lens at the telephoto end when focused on infinity; βrt: lateral magnification of the lens group Gr at the telephoto end when focused on infinity; βrw: lateral magnification of the lens group Gr at the wide-angle end when focused on infinity.

The zoom lens according to the second aspect of the present invention may be a zoom lens that satisfies the following formula in the first aspect.
Xp/(-Xn)≦1.0 (3)
however,
Xn: Amount of movement from the wide-angle end to the telephoto end of the lens group having at least one negative refractive power included in the composite lens group Gn. Xp: Wide-angle distance of the lens group having at least one positive refractive power included in the composite lens group Gp. Amount of movement from end to telephoto end

A zoom lens according to Aspect 3 of the present invention may be the zoom lens according to Aspect 1 or 2 described above, in which the composite lens group Gp has a negative refractive power and includes an image vibration reduction group Gv that moves in a direction perpendicular to the optical axis to correct image blur, and which satisfies the following formula:
0.65≦|fv|/fpt≦2.00 (4)
however,
fv: focal length of the image stabilization group Gv fpt: focal length at the telephoto end of the composite lens group Gp

The zoom lens according to aspect 4 of the present invention may be a zoom lens that satisfies the following formula in any one of aspects 1 to 3 above.
0.35≦Lt/ft≦0.70 (5)
however,
Lt: Total optical length of the zoom lens at the telephoto end when focused at infinity

The zoom lens according to aspect 5 of the present invention may be a zoom lens that satisfies the following formula in any one of aspects 1 to 4 above.
5.0≦｜{1-(βft) ² }×(βcrt) ² |≦13.0・・・・・・(6)
however,
βft: Lateral magnification at the telephoto end when lens group Gf is focused at infinity βcrt: Lateral magnification at the telephoto end when all lens groups on the image plane side than lens group Gf are focused at infinity

In the zoom lens according to aspect 6 of the present invention, in any one of aspects 1 to 5 above, lens group G1 includes one or more lenses having negative refractive power, and satisfies the following formula. , it may also be used as a zoom lens.
-0.012≦ΔPgF1≦-0.001 (7)
however,
ΔPgF1: Anomalous dispersion of at least one lens having negative refractive power included in lens group G1

A zoom lens according to Aspect 7 of the present invention may be the zoom lens according to any one of Aspects 1 to 6, which satisfies the following formula:
0.015≦ΔPgFr≦0.050 (8)
however,
ΔPgFr: Anomalous dispersion of at least one lens having negative refractive power included in the lens group Gr

The zoom lens according to aspect 8 of the present invention may be a zoom lens that satisfies the following expression in any one of aspects 1 to 7 above.
0.05≦fpt/ft≦0.20 (9)
however,
fpt: focal length of composite lens group Gp at telephoto end

A zoom lens according to Aspect 9 of the present invention may be the zoom lens according to any one of Aspects 1 to 8, which satisfies the following formula:
0.40≦f1/fw≦3.00 (10)
however,
f1: focal length of lens group G1 fw: focal length at the wide-angle end of the zoom lens when focused at infinity

A zoom lens according to Aspect 10 of the present invention may be a zoom lens according to any one of Aspects 1 to 9 above, which satisfies the following formula:
0.28≦f1/ft≦0.55 (11)
however,
f1: focal length of lens group G1

A zoom lens according to aspect 11 of the present invention includes the zoom lens according to any one of aspects 1 to 10 above, and is provided on the image plane side of the zoom lens, and converts an optical image formed by the zoom lens into an electrical signal. The image capturing device may include an image capturing element that performs conversion.

An embodiment of the present invention will be described below. In the following tables, all lengths are in mm, all angles of view are in degrees, and "E+a" indicates "×10 ^a ."

[Example 1]
FIG. 1 is a diagram showing the optical configuration of the zoom lens of Example 1 at the wide-angle end when focusing at infinity. The zoom lens of Example 1 is composed of, in order from the object side, a first lens group G1 having positive refractive power, a second lens group G2 having negative refractive power, a third lens group G3 having positive refractive power, a fourth lens group G4 having negative refractive power, and a fifth lens group G5 having negative refractive power. The first lens group G1 includes a first sub-a group G1a having positive refractive power and a first sub-b group G1b having positive refractive power. The third lens group G3 includes a sub-group Gv having negative refractive power. An aperture stop S is arranged in the third lens group G3. "IP" shown in FIG. 1 is an image plane.

The first lens group G1 is composed of, in order from the object side, a biconvex lens L1, a cemented lens of a biconvex lens L2 and a biconcave lens L3, and a biconvex lens L4. The first sub-a group G1a is composed of lens L1. The first sub-b group G1b is composed of a cemented lens of lens L2 and lens L3, and lens L4.

The second lens group G2 includes, in order from the object side, a cemented lens of a biconvex lens L5 and a biconcave lens L6, a biconcave lens L7, and a biconcave lens L8.

The third lens group G3 is composed of, in order from the object side, a biconvex lens L9, a positive meniscus lens L10 with its convex surface facing the object side, a cemented lens of a biconvex lens L11 and a biconcave lens L12, a biconvex lens L13, a triplet cemented lens of a negative meniscus lens L14 with its convex surface facing the object side, a biconvex lens L15 and a biconcave lens L16, a cemented lens of a positive meniscus lens L17 with its concave surface facing the object side and a biconcave lens L18, and a biconvex lens L19. The cemented lens of lenses L17 and L18 constitutes a subgroup Gv. The subgroup Gv is arranged to be movable in a direction perpendicular to the optical axis so as to correct image blur.

The fourth lens group G4 is composed of a negative meniscus lens L20 with a convex surface facing the object side.

The fifth lens group G5 includes, in order from the object side, a cemented lens of a biconcave lens L21 and a biconvex lens L22, a cemented lens of a biconvex lens L23 and a biconcave lens L24, and a negative meniscus lens L25 with a concave surface facing the object side. configured. The negative meniscus lens L25 is a composite resin type aspherical lens in which a composite resin film molded into an aspherical shape is attached to the object side surface.

In the zoom lens of Example 1, the first lens group G1 corresponds to the lens group G1 described above. The first sub-a group G1a corresponds to the sub-group G1a described above, and the first sub-b group G1b corresponds to the sub-group G1b described above. The second lens group G2 corresponds to the composite lens group Gn described above. The third lens group G3 corresponds to the composite lens group Gp described above. The fourth lens group G4 corresponds to the lens group Gf described above. The fifth lens group G5 corresponds to the lens group Gr described above. The first lens group G1 and the second lens group G2 correspond to the front group described above. The third lens group G3, the fourth lens group G4, and the fifth lens group G5 correspond to the rear group described above. The sub-group Gv corresponds to the vibration isolation group Gv described above.

The zoom lens of Example 1 performs a zooming operation by changing the distance between adjacent lens groups on the optical axis. In the figure, the arrows shown below each lens group at the wide-angle end indicate the locus of movement of each lens group when moving from the wide-angle end to the telephoto end. During zooming from the wide-angle end to the telephoto end, the first lens group G1 is fixed, the second lens group G2 moves on the optical axis toward the image plane, and the third lens group G3, fourth lens group G4, And the fifth lens group G5 moves on the optical axis toward the object side. During focusing, the fourth lens group G4 moves on the optical axis.

Next, we will explain an example in which specific numerical values of a zoom lens are applied. Table 1 shows the surface data of the zoom lens in Example 1.

In the surface data tables for the embodiments of the present invention, "surface number" refers to the order of the lens surface counted from the object side, "r" refers to the radius of curvature of the lens surface, "d" refers to the distance on the optical axis of the lens surface, "nd" refers to the refractive index for the d-line (wavelength λ=587.56 nm), and "νd" refers to the Abbe number for the d-line. In addition, the "S" designation in the surface number indicates that it is an aperture, and the "ASPH" designation indicates that the lens surface is aspheric. Furthermore, the designations "d(7)", "d(14)", etc. in the "d" column indicate that the distance on the optical axis of the lens surface is a variable distance that changes when changing magnification or focusing.

In Table 1, No. 1 to 7 are surface numbers of the first lens group G1; 8 to 14 are surface numbers of the second lens group G2. No. 15 to 33 are surface numbers of the third lens group G3; 22 represents an aperture stop. No. 34 and 35 are surface numbers of the fourth lens group G4; 36 to 44 are surface numbers of the fifth lens group G5. Note that the surface number of the object surface is "0", which is 1 smaller than the minimum value in the table. The surface number of the image plane is 1 larger than the maximum value in the table, and is "45" in this example.

[Table 1]
Surface number rd nd νd
Object plane ∞ d(0)
1 182.4497 10.0000 1.48749 70.44
2 -403.6984 26.6202
3 188.4803 9.3461 1.49700 81.61
4 -223.4841 2.7000 1.83481 42.72
5 262.8225 3.0000
6 242.8417 5.4615 1.49700 81.61
7 -1183.0117 d(7)
8 84.0753 7.2331 1.80610 33.27
9 -128.8885 1.5000 1.48749 70.44
10 62.3275 5.0723
11 -199.9849 1.7000 1.80420 46.50
12 176.6502 3.5867
13 -102.4296 1.5000 1.83481 42.72
14 185.5932 d(14)
15 121.4017 4.1486 1.80518 25.46
16 -454.9999 0.2000
17 43.9537 6.4374 1.49700 81.61
18 383.2534 0.2000
19 43.6627 7.3975 1.49700 81.61
20 -150.4361 1.5000 1.83400 37.34
21 55.9208 8.6104
22 S ∞ 2.5000
23 159.8368 3.3696 1.60562 43.71
24 -127.0059 0.2000
25 52.0010 1.2000 2.00069 25.46
26 19.2714 8.3553 1.51823 58.96
27 -39.5892 1.2000 1.83481 42.72
28 417.8253 2.7578
29 -109.8115 3.0362 1.80610 33.27
30 -40.3853 1.1000 1.63930 44.87
31 74.3588 2.3776
32 46.1051 3.9921 1.80518 25.46
33 -164.7419 d(33)
34 190.4021 1.0000 1.59282 68.62
35 36.1350 d(35)
36 -56.6572 1.1000 1.92286 20.88
37 25.1658 6.9096 1.68893 31.16
38 -32.9514 0.7000
39 90.9865 7.1625 1.75211 25.05
40 -20.6569 1.2000 1.59282 68.62
41 152.7300 4.3386
42 ASPH -33.2505 0.2500 1.53610 41.21
43 -34.1891 1.5000 1.87070 40.73
44 -82.3749 d(44)
Image plane ∞

Table 2 shows the specifications of the zoom lens of Example 1. In this specification table, from the left, the numerical values are shown for the wide-angle end, the intermediate focal length state, and the telephoto end. In this specification table, "f" represents the focal length of the zoom lens when focused at infinity, "FNo." represents the F-number, "ω" represents the half angle of view, and "Y" represents the maximum image height. Also, in the specification table, "d(n)" (n is an integer) represents the variable distance on the optical axis of the zoom lens when changing the magnification.

[Table 2]
Wide-angle end Mid-range Telephoto end
f 184.9819 349.9912 582.1707
F No. 5.1502 5.6457 6.5297
ω 6.5781 3.4710 2.1003
Y 21.6330 21.6330 21.6330
Wide-angle end Mid-range Telephoto end Wide-angle end Mid-range Telephoto end
d(0) ∞ ∞ ∞ 2070.5451 2070.5451 2070.5450
d(7) 8.4054 46.3531 63.0476 8.4054 46.3531 63.0476
d(14) 79.1475 35.7220 1.2000 79.1475 35.7220 1.2000
d(33) 3.0021 5.7207 3.9418 5.9658 16.0325 27.6185
d(35) 29.8255 27.1070 28.8859 26.8619 16.7952 5.2091
d(44) 48.6113 54.0890 71.9167 48.6113 54.0890 71.9167

Table 3 shows the aspheric coefficients of each aspheric surface in the zoom lens of Example 1. The aspheric coefficients in this table are values when each aspheric surface shape is defined by the following formula.
[Formula] z = ch ² / [1 + {1 - (1 + k) c ² h ² } ^1/2 ] + A 4 h ⁴ + A 6 h ⁶ + A 8 ^{h 8} + A ^{10 h 10} + A ^{12 h 12}

In the above formula, "z" is the displacement amount of the aspherical surface in the optical axis direction from the reference plane perpendicular to the optical axis, "c" is the curvature (1/r), "h" is the height from the optical axis, and " k" is a conical coefficient, and "An" (n is an integer) is an n-order aspherical coefficient. Note that the aspheric coefficients of surface numbers that are not displayed are 0.

[Table 3]
Surface number k A4 A6
42 0.0000 5.44991E-06 3.77913E-09
Surface number A8 A10 A12
42 1.20134E-11 8.72519E-14 -1.90492E-16

Table 4 shows the focal length of each lens group constituting the zoom lens of Example 1.

[Table 4]
Group number Focal length
G1 233.0280
G2 -65.3334
G3 60.5168
G4 -75.4136
G5 -218.2960

Figures 2, 3, and 4 are diagrams showing longitudinal aberrations of the zoom lens of Example 1 at the wide-angle end, in the intermediate focal length state, and at the telephoto end when focusing on infinity, respectively. The longitudinal aberrations shown in each figure are, from the left as you face the figure, spherical aberration (SA (mm)), astigmatism (AST (mm)), and distortion aberration (DIS (%)), respectively. The same applies to the other examples.

In the diagram showing spherical aberration, the vertical axis is the F number and the horizontal axis is defocus. In the diagram representing spherical aberration, the solid line represents the spherical aberration at the d-line (wavelength λ = 587.56 nm), the broken line represents the spherical aberration at the C-line (wavelength λ = 656.27 nm), and the dashed line represents the spherical aberration at the g-line (wavelength λ = 435.84 nm). show.

In the diagram showing astigmatism, the vertical axis represents the half angle of view, and the horizontal axis represents defocus. In the figure showing astigmatism, the solid line shows the astigmatism in the sagittal image plane (indicated by ds in the figure) for the d-line, and the broken line shows the astigmatism in the meridional plane (indicated by dm in the figure) for the d-line.

In the graph showing distortion, the vertical axis represents half angle of view, and the horizontal axis represents percentage.

[Example 2]
FIG. 5 is a diagram showing the optical configuration of the zoom lens of Example 2 at the wide-angle end when focusing on infinity. FIG. 6, FIG. 7, and FIG. 8 are diagrams showing longitudinal aberrations of the zoom lens of Example 2 at the wide-angle end, the intermediate focal length state, and the telephoto end when focusing on infinity, respectively. The zoom lens of Example 2 is composed of, in order from the object side, a first lens group G1 having positive refractive power, a second lens group G2 having negative refractive power, a third lens group G3 having negative refractive power, a fourth lens group G4 having positive refractive power, a fifth lens group G5 having negative refractive power, and a sixth lens group G6 having negative refractive power. The first lens group G1 includes a first sub-a group G1a having positive refractive power and a first sub-b group G1b having positive refractive power. The fourth lens group G4 includes a sub-group Gv having negative refractive power. An aperture stop S is arranged in the fourth lens group G4.

The first lens group G1 includes, in order from the object side, a biconvex lens L1, a cemented lens of a biconvex lens L2 and a biconcave lens L3, and a biconvex lens L4. The first sub-a group G1a is composed of a lens L1. The first sub-b group G1b is composed of a cemented lens of a lens L2 and a lens L3, and a lens L4.

The second lens group G2 includes, in order from the object side, a cemented lens of a biconvex lens L5 and a biconcave lens L6, and a biconcave lens L7.

The third lens group G3 is composed of a biconcave lens L8.

The fourth lens group G4 includes, in order from the object side, a biconvex lens L9, a positive meniscus lens L10 with a convex surface facing the object side, a cemented lens of a biconvex lens L11 and a biconcave lens L12, a biconvex lens L13, and a biconvex lens L13 on the object side. Consists of a three-piece cemented lens consisting of a negative meniscus lens L14 with a convex surface facing, a biconvex lens L15, and a biconcave lens L16, a cemented lens with a positive meniscus lens L17 and a biconcave lens L18 with a concave surface facing the object side, and a biconvex lens L19. be done. The cemented lens of lenses L17 and L18 constitutes a sub-group Gv. The sub group Gv is arranged so as to be movable in a direction perpendicular to the optical axis so as to correct image blur.

The fifth lens group G5 is composed of a negative meniscus lens L20 with its convex surface facing the object side.

The sixth lens group G6 is composed of, from the object side, a cemented lens of a biconcave lens L21 and a biconvex lens L22, a cemented lens of a biconvex lens L23 and a biconcave lens L24, and a negative meniscus lens L25 with its concave surface facing the object side. The negative meniscus lens L25 is a composite resin type aspherical lens with a composite resin film molded into an aspherical shape attached to the object side surface.

In the zoom lens of Example 2, the first lens group G1 corresponds to the aforementioned lens group G1. The first sub-group a G1a corresponds to the above-mentioned sub-group G1a, and the first sub-group B G1b corresponds to the above-mentioned sub-group G1b. The second lens group G2 and the third lens group G3 correspond to the above-mentioned composite lens group Gn. The fourth lens group G4 corresponds to the above-mentioned composite lens group Gp. The fifth lens group G5 corresponds to the above-mentioned lens group Gf. The sixth lens group G6 corresponds to the above-mentioned lens group Gr. The first lens group G1, the second lens group G2, and the third lens group G3 correspond to the above-mentioned front group. The fourth lens group G4, the fifth lens group G5, and the sixth lens group G6 correspond to the aforementioned rear group. The sub-group Gv corresponds to the above-mentioned anti-vibration group Gv.

The zoom lens of Example 2 performs a zooming operation by changing the distance between adjacent lens groups on the optical axis. When changing the magnification from the wide-angle end to the telephoto end, the first lens group G1 is fixed, the second lens group G2 and the third lens group G3 move on the optical axis toward the image plane, and the fourth lens group G4, The fifth lens group G5 and the sixth lens group G6 move on the optical axis toward the object side. During focusing, the fifth lens group G5 moves on the optical axis.

Table 5 is a table of surface data for the zoom lens of Example 2. In Table 5, No. 1 to 7 are surface numbers of the first lens group G1, No. 8 to 12 are surface numbers of the second lens group G2, and No. 13 and 14 are surface numbers of the third lens group G3. No. 15 to 33 are surface numbers of the fourth lens group G4, and No. 22 represents the aperture stop. No. 34 and 35 are surface numbers of the fifth lens group G5, and No. 36 to 44 are surface numbers of the sixth lens group G6.

[Table 5]
Surface number rd nd νd
Object plane ∞ d(0)
1 172.3685 10.0000 1.48749 70.44
2 -466.6312 26.9019
3 187.3246 9.2687 1.49700 81.61
4 -230.5965 2.5000 1.83481 42.72
5 246.0023 3.0000
6 190.2720 6.2969 1.49700 81.61
7 -1072.1852 d(7)
8 77.8587 7.3231 1.80610 33.27
9 -142.2214 1.5000 1.48749 70.44
10 63.5272 4.7685
11 -244.1937 1.7000 1.80420 46.50
12 104.9919 d(12)
13 -97.9818 1.5000 1.83481 42.72
14 194.4426 d(14)
15 105.6778 4.1057 1.80518 25.46
16 -659.0602 0.2000
17 44.4203 5.8251 1.49700 81.61
18 334.8743 0.2000
19 46.5822 7.9673 1.49700 81.61
20 -114.8096 1.5000 1.83400 37.34
21 63.6089 6.7379
22 S∞2.5000
23 234.0486 3.3421 1.60562 43.71
24 -102.1570 0.6914
25 53.1148 1.2000 2.00069 25.46
26 19.4680 8.3914 1.51823 58.96
27 -36.8410 1.2000 1.83481 42.72
28 1906.2293 2.6088
29 -119.1446 2.9444 1.80610 33.27
30 -41.8259 1.1000 1.63930 44.87
31 73.0637 2.2178
32 45.2983 3.9688 1.80518 25.46
33 -174.4977 d(33)
34 152.9104 1.0000 1.59282 68.62
35 34.1887 d(35)
36 -37.7950 1.1000 1.92286 20.88
37 26.7942 7.4286 1.68893 31.16
38 -28.1806 0.7000
39 155.7716 7.7609 1.75211 25.05
40 -19.4971 1.2000 1.59282 68.62
41 1515.7308 4.4453
42 ASPH -30.8499 0.2500 1.53610 41.21
43 -32.1437 1.5000 1.87070 40.73
44 -56.9736 d(44)
Image plane ∞

Table 6 shows the specifications of the zoom lens of Example 2. Table 7 shows the aspheric coefficients of each aspheric surface in the zoom lens of Example 2. Table 8 shows the focal lengths of each lens group constituting the zoom lens of Example 2.

[Table 6]
Wide-angle end Intermediate Telephoto end
f 185.0086 350.0125 582.1636
FNo. 5.8014 6.1650 6.5296
ω 6.5999 3.4907 2.1082
Y 21.6330 21.6330 21.6330
Wide-angle end Intermediate Telephoto end Wide-angle end Intermediate Telephoto end
d(0) ∞ ∞ ∞ 2070.5448 2070.5449 2070.5446
d(7) 12.5172 39.4888 56.7686 12.5172 39.4888 56.7686
d(12) 4.6966 5.6756 4.9219 4.6966 5.6756 4.9219
d(14) 74.8686 33.7845 1.2000 74.8686 33.7845 1.2000
d(33) 2.9989 6.4865 4.6940 5.9374 15.8708 27.4934
d(35) 31.6550 28.1675 29.9599 28.7165 18.7832 7.1606
d(44) 45.8745 59.0079 75.0666 45.8745 59.0079 75.0666

[Table 7]
Surface number k A4 A6
42 0.0000 5.33455E-06 7.84308E-09
Surface number A8 A10 A12
42 -2.79958E-11 2.54947E-13 -4.75745E-16

[Table 8]
Group Number Focal Length
G1 214.6420
G2 -207.4500
G3 -77.8618
G4 57.5179
G5 -74.5122
G6 -258.8370

[Example 3]
9 is a diagram showing the optical configuration of the zoom lens of Example 3 at the wide-angle end when focusing on infinity. FIGS. 10, 11, and 12 are diagrams showing longitudinal aberrations of the zoom lens of Example 3 at the wide-angle end, the intermediate focal length state, and the telephoto end when focusing on infinity, respectively. The zoom lens of Example 3 is composed of, in order from the object side, a first lens group G1 having positive refractive power, a second lens group G2 having positive refractive power, a third lens group G3 having negative refractive power, a fourth lens group G4 having positive refractive power, a fifth lens group G5 having negative refractive power, and a sixth lens group G6 having negative refractive power. The first lens group G1 includes a first sub-a group G1a having positive refractive power and a first sub-b group G1b having positive refractive power. The fourth lens group G4 includes a sub-group Gv having negative refractive power. An aperture stop S is arranged in the fourth lens group G4.

The first lens group G1 is composed of, in order from the object side, a biconvex lens L1, a cemented lens of a biconvex lens L2 and a biconcave lens L3, and a biconvex lens L4. The first sub-a group G1a is composed of lens L1. The first sub-b group G1b is composed of a cemented lens of lens L2 and lens L3, and lens L4.

The second lens group G2 includes, in order from the object side, a biconvex lens L5 and a biconcave lens L6.

The third lens group G3 includes, in order from the object side, a negative meniscus lens L7 with a convex surface facing the object side, and a negative meniscus lens L8 with a concave surface facing the object side.

The fourth lens group G4 is composed of, in order from the object side, a biconvex lens L9, a positive meniscus lens L10 with its convex surface facing the object side, a cemented lens of a biconvex lens L11 and a biconcave lens L12, a biconvex lens L13, a triplet cemented lens of a negative meniscus lens L14 with its convex surface facing the object side, a biconvex lens L15 and a biconcave lens L16, a cemented lens of a positive meniscus lens L17 with its concave surface facing the object side and a biconcave lens L18, and a biconvex lens L19. The cemented lens of lenses L17 and L18 constitutes a subgroup Gv. The subgroup Gv is arranged to be movable in a direction perpendicular to the optical axis so as to correct image blur.

The fifth lens group G5 is composed of a negative meniscus lens L20 with a convex surface facing the object side.

The sixth lens group G6 is composed of, from the object side, a cemented lens of a biconcave lens L21 and a biconvex lens L22, a cemented lens of a biconvex lens L23 and a biconcave lens L24, and a negative meniscus lens L25 with its concave surface facing the object side. The negative meniscus lens L25 is a composite resin type aspherical lens with a composite resin film molded into an aspherical shape attached to the object side surface.

In the zoom lens of Example 3, the first lens group G1 corresponds to the lens group G1 described above. The first sub-a group G1a corresponds to the sub-group G1a described above, and the first sub-b group G1b corresponds to the sub-group G1b described above. The second lens group G2 and the third lens group G3 correspond to the composite lens group Gn described above. The fourth lens group G4 corresponds to the composite lens group Gp described above. The fifth lens group G5 corresponds to the lens group Gf described above. The sixth lens group G6 corresponds to the lens group Gr described above. The first lens group G1, the second lens group G2, and the third lens group G3 correspond to the front group described above. The fourth lens group G4, the fifth lens group G5, and the sixth lens group G6 correspond to the rear group described above. The sub group Gv corresponds to the vibration isolation group Gv described above.

The zoom lens of Example 3 performs a zooming operation by changing the distance between adjacent lens groups on the optical axis. When changing the magnification from the wide-angle end to the telephoto end, the first lens group G1 is fixed, the second lens group G2 and the third lens group G3 move on the optical axis toward the image plane, and the fourth lens group G4, The fifth lens group G5 and the sixth lens group G6 move on the optical axis toward the object side. During focusing, the fifth lens group G5 moves on the optical axis.

Table 9 is a table of surface data for the zoom lens of Example 3. In Table 9, No. 1 to 7 are surface numbers of the first lens group G1, No. 8 to 11 are surface numbers of the second lens group G2, and No. 12 to 15 are surface numbers of the third lens group G3. No. 16 to 34 are surface numbers of the fourth lens group G4, and No. 23 represents the aperture stop. No. 35 and 36 are surface numbers of the fifth lens group G5, and No. 37 to 45 are surface numbers of the sixth lens group G6.

[Table 9]
Surface number rd nd νd
Object plane ∞ d(0)
1 175.2847 10.0000 1.48749 70.44
2 -445.8112 27.1481
3 204.0444 8.6050 1.49700 81.61
4 -233.5655 2.7000 1.83481 42.72
5 280.2832 3.0000
6 187.6493 6.0365 1.49700 81.61
7 -2236.2229 d(7)
8 96.1318 5.5977 1.77047 29.74
9 -349.0675 1.4104
10 -460.7200 1.5000 1.59349 67.00
11 82.5279 d(11)
12 747.7002 1.5000 1.74330 49.22
13 78.8618 5.9572
14 -70.0752 1.5000 1.77250 49.62
15 -2767.1835 d(15)
16 133.5099 3.9572 1.80518 25.46
17 -571.5164 0.2000
18 48.0149 6.6337 1.49700 81.61
19 2953.3024 0.2000
20 47.1234 10.0000 1.49700 81.61
21 -114.8386 1.5000 1.83400 37.34
22 69.3677 3.8799
23 S∞7.6694
24 263.4682 3.1546 1.60562 43.71
25 -110.2858 0.2000
26 55.4420 1.2000 2.00069 25.46
27 19.1999 8.1782 1.51823 58.96
28 -37.1350 1.2000 1.83481 42.72
29 1552.3735 2.6407
30 -108.5796 3.0672 1.80610 33.27
31 -39.6094 1.1000 1.63930 44.87
32 73.8435 2.3655
33 45.4628 4.1159 1.80518 25.46
34 -144.8730 d(34)
35 171.2908 1.0000 1.59282 68.62
36 35.5787 d(36)
37 -35.6989 1.1000 1.92286 20.88
38 31.2562 7.1269 1.68893 31.16
39 -26.6093 0.7000
40 91.5706 7.4959 1.75211 25.05
41 -20.9094 1.2000 1.59282 68.62
42 405.9052 4.2269
43 ASPH -32.8943 0.1500 1.53610 41.21
44 -35.3610 1.5000 1.87070 40.73
45 -96.0677 d(45)
Image plane ∞

Table 10 shows a specification table of the zoom lens of Example 3. Table 11 is a table showing aspherical coefficients of each aspherical surface in the zoom lens of Example 3. Table 12 shows the focal length of each lens group constituting the zoom lens of Example 3.

[Table 10]
Wide-angle end Intermediate Telephoto end
f 184.9759 350.0057 582.1347
FNo. 5.1699 5.7007 6.5258
ω 6.5695 3.4726 2.1003
Y 21.6330 21.6330 21.6330
Wide-angle end Intermediate Telephoto end Wide-angle end Intermediate Telephoto end
d(0) ∞ ∞ ∞ 2070.5451 2070.5451 2070.5451
d(7) 6.1221 40.7465 58.0025 6.1221 40.7465 58.0025
d(11) 5.3889 4.7208 3.6164 5.3889 4.7208 3.6164
d(15) 76.2871 34.9116 1.2000 76.2871 34.9116 1.2000
d(34) 3.0029 5.5514 3.7973 5.9848 15.5963 26.9742
d(36) 29.7175 27.1691 28.9231 26.7356 17.1241 5.7462
d(45) 48.2194 55.6386 73.1988 48.2194 55.6386 73.1988

[Table 11]
Surface number k A4 A6
43 0.0000 4.24654E-06 6.80969E-10
Surface number A8 A10 A12
43 2.12552E-11 -8.31897E-15 -1.10171E-16

[Table 12]
Group number Focal length
G1 214.6950
G2 480.0070
G3 -50.7792
G4 61.0824
G5 -75.9577
G6 -211.8270

[Example 4]
FIG. 13 is a diagram schematically showing the optical configuration of the zoom lens of Example 4 at the wide-angle end when focusing on infinity. 14, 15, and 16 are diagrams showing the longitudinal aberration of the zoom lens of Example 4 at the wide-angle end, intermediate focal length state, and telephoto end when focusing at infinity, respectively. The zoom lens of Example 4 includes, in order from the object side, a first lens group G1 having a positive refractive power, a second lens group G2 having a negative refractive power, and a third lens group G3 having a positive refractive power. , a fourth lens group G4 having a positive refractive power, a fifth lens group G5 having a negative refractive power, and a sixth lens group G6 having a negative refractive power. The first lens group G1 includes a first sub-a group G1a having a positive refractive power and a first sub-b group G1b having a negative refractive power. The fourth lens group G4 includes a sub-group Gv having negative refractive power. An aperture stop S is arranged between the third lens group G3 and the fourth lens group G4.

The first lens group G1 is composed of, in order from the object side, a biconvex lens L1, a positive meniscus lens L2 with its convex surface facing the object side, and a cemented lens of a biconvex lens L3 and a biconcave lens L4. The first sub-a group G1a is composed of lens L1. The first sub-b group G1b is composed of a cemented lens of lens L2 and lens L3, and lens L4.

The second lens group G2 includes, in order from the object side, a cemented lens consisting of a positive meniscus lens L5 with a convex surface facing the object side, a negative meniscus lens L6 with a convex surface facing the object side, and a positive meniscus lens with a concave surface facing the object side. It is composed of a cemented lens of a lens L7 and a biconcave lens L8, and a biconcave lens L9.

The third lens group G3 includes, in order from the object side, a positive meniscus lens L10 with a convex surface facing the object side, a biconvex lens L11, and a cemented lens of a biconvex lens L12 and a biconcave lens L13.

The fourth lens group G4 includes, in order from the object side, a biconvex lens L14, a negative meniscus lens L15 with a convex surface facing the object side, a three-piece cemented lens consisting of a biconvex lens L16, a biconcave lens L17, and a concave surface facing the object side. The lens is composed of a cemented lens of a positive meniscus lens L18 and a biconcave lens L19, and a cemented lens of a negative meniscus lens L20 with a convex surface facing the object side and a biconvex lens L21. The cemented lens of lenses L18 and L19 constitutes a sub-group Gv. The sub group Gv is arranged so as to be movable in a direction perpendicular to the optical axis so as to correct image blur.

The fifth lens group G5 is composed of, from the object side, a cemented lens consisting of a biconvex lens L22 and a biconcave lens L23.

The sixth lens group G6 is composed of, in order from the object side, a cemented lens of a negative meniscus lens L24 with its convex surface facing the object side and a biconvex lens L25, a cemented lens of a biconvex lens L26 and a biconcave lens L27, and a negative meniscus lens L28 with its concave surface facing the object side. The negative meniscus lens L28 is a composite resin type aspherical lens with a composite resin film molded into an aspherical shape attached to the object side surface.

In the zoom lens of Example 4, the first lens group G1 corresponds to the aforementioned lens group G1. The first sub-group a G1a corresponds to the above-mentioned sub-group G1a, and the first sub-group B G1b corresponds to the above-mentioned sub-group G1b. The second lens group G2 corresponds to the above-mentioned composite lens group Gn. The third lens group G3 and the fourth lens group G4 correspond to the above-mentioned composite lens group Gp. The fifth lens group G5 corresponds to the above-mentioned lens group Gf. The sixth lens group G6 corresponds to the above-mentioned lens group Gr. The first lens group G1 and the second lens group G2 correspond to the above-mentioned front group. The third lens group G3, the fourth lens group G4, the fifth lens group G5, and the sixth lens group G6 correspond to the aforementioned rear group. The sub-group Gv corresponds to the above-mentioned anti-vibration group Gv.

The zoom lens of Example 4 performs a magnification change operation by changing the distance on the optical axis between adjacent lens groups. When changing magnification from the wide-angle end to the telephoto end, the first lens group G1 is fixed, the second lens group G2 moves on the optical axis toward the image surface, and the third lens group G3, the fourth lens group G4, the fifth lens group G5, and the sixth lens group G6 move on the optical axis toward the object side. When focusing, the fifth lens group G5 moves on the optical axis.

Table 13 is a table of surface data of the zoom lens of Example 4. In Table 13, No. 1 to 7 are surface numbers of the first lens group G1; 8 to 15 are surface numbers of the second lens group G2. No. 16 to 22 are surface numbers of the third lens group G3; 23 represents an aperture stop, and No. 24 to 35 are surface numbers of the fourth lens group G4. No. 36 to 38 are surface numbers of the fifth lens group G5, and No. 39 to 47 are surface numbers of the sixth lens group G6.

[Table 13]
Surface number rd nd νd
Object plane ∞ d(0)
1 151.9293 10.6000 1.48749 70.44
2 -519.5684 29.7855
3 162.9951 5.9575 1.49700 81.61
4 1728.8044 0.8809
5 168.1106 8.2820 1.49700 81.61
6 -252.8425 3.0000 1.83481 42.72
7 157.1010 d(7)
8 60.4454 4.2150 1.80000 29.84
9 96.7504 1.7000 1.69680 55.46
10 50.4170 6.5910
11 -1588.5187 4.8519 1.80100 34.97
12 -77.7510 1.5000 1.49700 81.61
13 112.4948 4.6838
14 -80.2541 1.5000 1.83481 42.72
15 464.1728 d(15)
16 101.1685 4.1195 1.60562 43.71
17 2256.2991 0.2000
18 45.0963 7.9170 1.49700 81.61
19 -317.1815 0.2000
20 49.5278 8.2285 1.49700 81.61
21 -99.2343 1.5000 1.87070 40.73
22 88.4540 d(22)
23 S∞5.5275
24 960.0559 4.6327 1.51680 64.20
25 -90.8481 0.2000
26 54.8461 1.2000 1.91082 35.25
27 17.9262 8.8947 1.54814 45.78
28 -28.2645 1.2000 1.83481 42.72
29 330.2866 3.1317
30 -63.7040 3.6264 1.80610 33.27
31 -27.9860 1.1000 1.61772 49.81
32 63.4711 2.4267
33 44.7427 1.2000 1.90366 31.31
34 25.1696 5.6665 1.83400 37.34
35 -110.2890 d(35)
36 502.1105 3.1020 1.63854 55.38
37 -38.0143 1.0000 1.59282 68.62
38 31.3566 d(38)
39 138.3535 1.1000 1.92286 20.88
40 21.3454 7.0000 1.59270 35.31
41 -38.1411 0.2000
42 54.4899 7.1270 1.75520 27.51
43 -20.4237 1.2000 1.69680 55.46
44 41.9476 5.9746
45 ASPH -20.8854 0.2500 1.53610 41.21
46 -23.0668 1.5000 1.91082 35.25
47 -31.8491 d(47)
Image plane ∞

Table 14 shows a specification table of the zoom lens of Example 4. Table 15 is a table showing aspherical coefficients of each aspherical surface in the zoom lens of Example 4. Table 16 shows the focal length of each lens group constituting the zoom lens of Example 4.

[Table 14]
Wide-angle end Intermediate Telephoto end
f 185.0329 350.1211 582.2405
FNo. 5.1476 5.6976 6.5270
ω 6.6359 3.5169 2.1317
Y 21.6330 21.6330 21.6330
Wide-angle end Intermediate Telephoto end Wide-angle end Intermediate Telephoto end
d(0) ∞ ∞ ∞ 2070.5452 2070.5451 2070.5451
d(7) 1.5026 37.1050 55.5806 1.5026 37.1050 55.5806
d(15) 84.4457 37.8434 1.2000 84.4457 37.8434 1.2000
d(22) 4.2766 4.9044 5.8547 4.2766 4.9044 5.8547
d(35) 2.4964 4.3921 2.5016 5.6699 14.1487 24.8465
d(38) 17.9610 18.2330 28.7515 14.7875 8.4764 6.4067
d(47) 45.8001 54.0045 62.5941 45.8001 54.0045 62.5941

[Table 15]
Surface number k A4 A6
45 0.0000 2.07917E-05 2.90901E-08
Surface number A8 A10 A12
45 1.08256E-10 6.48354E-14 4.34761E-16

[Table 16]
Group Number Focal Length
G1 259.4720
G2 -71.9529
G3 58.8966
G4 359.9130
G5 -61.1261
G6 -488.0160

[Example 5]
Fig. 17 is a diagram showing the optical configuration of the zoom lens of Example 5 at the wide-angle end when focusing on infinity. Fig. 18, Fig. 19, and Fig. 20 are diagrams showing longitudinal aberrations of the zoom lens of Example 5 at the wide-angle end, the intermediate focal length state, and the telephoto end when focusing on infinity, respectively. The zoom lens of Example 5 is composed of, in order from the object side, a first lens group G1 having positive refractive power, a second lens group G2 having negative refractive power, a third lens group G3 having positive refractive power, a fourth lens group G4 having negative refractive power, a fifth lens group G5 having negative refractive power, and a sixth lens group G6 having negative refractive power. The first lens group G1 includes a first sub-a group G1a having positive refractive power and a first sub-b group G1b having positive refractive power. The fourth lens group G4 includes a sub-group Gv having negative refractive power. An aperture diaphragm S is disposed between the third lens group G3 and the fourth lens group G4.

The first lens group G1 includes, in order from the object side, a biconvex lens L1, a biconvex lens L2, and a cemented lens of a biconvex lens L3 and a biconcave lens L4. The first sub-a group G1a is composed of a lens L1. The first sub-b group G1b is composed of a cemented lens of a lens L2 and a lens L3, and a lens L4.

The second lens group G2 is composed of, in order from the object side, a cemented lens of a positive meniscus lens L5 with a convex surface facing the object side and a negative meniscus lens L6 with a convex surface facing the object side, a cemented lens of a positive meniscus lens L7 with a concave surface facing the object side and a biconcave lens L8, and a negative meniscus lens L9 with a concave surface facing the object side.

The third lens group G3 includes, in order from the object side, a positive meniscus lens L10 with a convex surface facing the object side, a biconvex lens L11, and a cemented lens of a biconvex lens L12 and a biconcave lens L13.

The fourth lens group G4 is a three-piece cemented lens consisting of, in order from the object side, a positive meniscus lens L14 with a concave surface facing the object side, a negative meniscus lens L15 with a convex surface facing the object side, a biconvex lens L16, and a biconcave lens L17. , a cemented lens of a positive meniscus lens L18 with a concave surface facing the object side and a biconcave lens L19, and a cemented lens of a negative meniscus lens L20 with a convex surface facing the object side and a biconvex lens L21. The cemented lens of lenses L18 and L19 constitutes a sub-group Gv. The sub group Gv is arranged so as to be movable in a direction perpendicular to the optical axis so as to correct image blur.

The fifth lens group G5 is composed of a cemented lens of a biconvex lens L22 and a biconcave lens L23 in order from the object side.

The sixth lens group G6 is composed of, in order from the object side, a cemented lens of a negative meniscus lens L24 with its convex surface facing the object side and a biconvex lens L25, a cemented lens of a biconvex lens L26 and a biconcave lens L27, and a negative meniscus lens L28 with its concave surface facing the object side. The negative meniscus lens L28 is a composite resin type aspherical lens with a composite resin film molded into an aspherical shape attached to the object side surface.

In the zoom lens of Example 5, the first lens group G1 corresponds to the aforementioned lens group G1. The first sub-group a G1a corresponds to the above-mentioned sub-group G1a, and the first sub-group B G1b corresponds to the above-mentioned sub-group G1b. The second lens group G2 corresponds to the above-mentioned composite lens group Gn. The third lens group G3 and the fourth lens group G4 correspond to the above-mentioned composite lens group Gp. The fifth lens group G5 corresponds to the above-mentioned lens group Gf. The sixth lens group G6 corresponds to the above-mentioned lens group Gr. The first lens group G1 and the second lens group G2 correspond to the above-mentioned front group. The third lens group G3, the fourth lens group G4, the fifth lens group G5, and the sixth lens group G6 correspond to the aforementioned rear group. The sub-group Gv corresponds to the above-mentioned anti-vibration group Gv.

The zoom lens of Example 5 performs a zooming operation by changing the distance between adjacent lens groups on the optical axis. During zooming from the wide-angle end to the telephoto end, the first lens group G1 is fixed, the second lens group G2 moves on the optical axis toward the image plane, and the third lens group G3, fourth lens group G4, The fifth lens group G5 and the sixth lens group G6 move on the optical axis toward the object side. During focusing, the fifth lens group G5 moves on the optical axis.

Table 17 is a table of surface data of the zoom lens of Example 5. In Table 17, No. 1 to 7 are surface numbers of the first lens group G1; 8 to 15 are surface numbers of the second lens group G2. No. 16 to 22 are surface numbers of the third lens group G3; 23 represents an aperture stop, and No. 24 to 35 are surface numbers of the fourth lens group G4. No. 36 to 38 are surface numbers of the fifth lens group G5, and No. 39 to 47 are surface numbers of the sixth lens group G6.

[Table 17]
Surface number rd nd νd
Object plane ∞ d(0)
1 169.8414 9.3235 1.48749 70.44
2 -728.1200 29.8699
3 150.3164 7.4299 1.49700 81.61
4 -1745.9586 0.2000
5 135.3383 8.8694 1.49700 81.61
6 -337.6166 3.0000 1.83481 42.72
7 135.5884 d(7)
8 63.9526 4.4632 1.80000 29.84
9 126.3700 1.7000 1.69680 55.46
10 48.3366 7.0467
11 -346.7227 4.5108 1.80100 34.97
12 -70.9343 1.5000 1.49700 81.61
13 128.1954 4.5956
14 -72.9113 1.5000 1.83481 42.72
15 -1506.6855 d(15)
16 91.0862 4.0894 1.60562 43.71
17 543.6365 0.2000
18 45.0435 7.9770 1.49700 81.61
19 -346.0660 0.2000
20 59.7389 7.4199 1.49700 81.61
21 -80.3697 1.5000 1.87070 40.73
22 239.4883 d(22)
23 S∞ 4.2707
24 -137.9289 4.0000 1.51680 64.20
25 -62.4885 0.2000
26 73.3823 1.2000 1.91082 35.25
27 19.4027 9.9310 1.54814 45.78
28 -24.9260 1.2000 1.83481 42.72
29 -1571.8078 2.9252
30 -64.4921 4.0000 1.80610 33.27
31 -28.8427 1.1000 1.61772 49.81
32 71.0222 2.4245
33 49.5594 1.2000 1.90366 31.31
34 24.6809 6.0948 1.83400 37.34
35 -107.1472 d(35)
36 560.7871 2.9173 1.63854 55.38
37 -44.4733 1.0000 1.59282 68.62
38 34.8639 d(38)
39 195.8798 1.1000 1.92286 20.88
40 22.5257 7.0000 1.59270 35.31
41 -35.8613 0.2000
42 53.3051 7.1677 1.75520 27.51
43 -20.3159 1.2000 1.69680 55.46
44 41.7380 6.4244
45 ASPH -19.2985 0.2500 1.53610 41.21
46 -21.2634 1.5000 1.91082 35.25
47 -29.7573 d(47)
Image plane ∞

Table 18 shows a specification table of the zoom lens of Example 5. Table 19 is a table showing aspherical coefficients of each aspherical surface in the zoom lens of Example 5. Table 20 shows the focal length of each lens group constituting the zoom lens of Example 5.

[Table 18]
Wide-angle end Mid-range Telephoto end
f 185.0226 350.1384 582.2199
F No. 5.1403 5.8832 6.5262
ω 6.6158 3.5115 2.1258
Y 21.6330 21.6330 21.6330
Wide-angle end Mid-range Telephoto end Wide-angle end Mid-range Telephoto end
d(0) ∞ ∞ ∞ 2070.5452 2070.5451 2070.5451
d(7) 3.6762 36.2957 55.3864 3.6762 36.2957 55.3864
d(15) 79.6736 36.0542 1.2000 79.6736 36.0542 1.2000
d(22) 4.7994 5.3564 6.2254 4.7994 5.3564 6.2254
d(35) 5.9404 7.3235 2.5023 9.5232 18.2514 27.2994
d(38) 19.4938 19.9576 30.4030 15.9110 9.0297 5.6059
d(47) 43.1703 51.7665 61.0368 43.1703 51.7665 61.0368

[Table 19]
Surface number k A4 A6
45 0.0000 2.18261E-05 2.25336E-08
Surface number A8 A10 A12
45 2.56953E-10 -8.42204E-13 2.76395E-15

[Table 20]
Group number Focal length
G1 236.3170
G2 -67.4597
G3 53.2018
G4 -2856.5300
G5 -67.6503
G6 -338.2150

[Example 6]
FIG. 21 is a diagram schematically showing the optical configuration of the zoom lens of Example 6 at the wide-angle end when focusing on infinity. FIGS. 22, 23, and 24 are diagrams showing longitudinal aberrations of the zoom lens of Example 6 at the wide-angle end, intermediate focal length state, and telephoto end when focusing at infinity, respectively. The zoom lens of Example 6 includes, in order from the object side, a first lens group G1 having a positive refractive power, a second lens group G2 having a negative refractive power, and a third lens group G3 having a positive refractive power. , a fourth lens group G4 having negative refractive power, and a fifth lens group G5 having negative refractive power. The first lens group G1 includes a first sub-a group G1a having a positive refractive power and a first sub-b group G1b having a positive refractive power. The third lens group G3 includes a sub-group Gv having negative refractive power. An aperture stop S is arranged within the third lens group G3.

The first lens group G1 is composed of, in order from the object side, a biconvex lens L1, a biconvex lens L2, and a cemented lens of a biconvex lens L3 and a biconcave lens L4. The first sub-a group G1a is composed of lens L1. The first sub-b group G1b is composed of a cemented lens of lens L2 and lens L3, and lens L4.

The second lens group G2 is composed of, in order from the object side, a cemented lens of a biconvex lens L5 and a biconcave lens L6, a cemented lens of a positive meniscus lens L7 with its concave surface facing the object side and a biconcave lens L8, and a biconcave lens L9.

The third lens group G3 includes, in order from the object side, a positive meniscus lens L10 with a convex surface facing the object side, a biconvex lens L11, a cemented lens of a biconvex lens L12 and a biconcave lens L13, and a concave surface facing the object side. A three-piece cemented lens consisting of a positive meniscus lens L14, a negative meniscus lens L15 with a convex surface facing the object side, a biconvex lens L16, and a biconcave lens L17, and a positive meniscus lens L18 with a concave surface facing the object side and a biconcave lens L19. It is composed of a cemented lens, a negative meniscus lens L20 with a convex surface facing the object side, and a biconvex lens L21. The cemented lens of lenses L18 and L19 constitutes a sub-group Gv. The sub group Gv is arranged so as to be movable in a direction perpendicular to the optical axis so as to correct image blur.

The fourth lens group G4 is composed of, in order from the object side, a cemented lens of a positive meniscus lens L22 with a concave surface and a biconcave lens L23.

The fifth lens group G5 includes, in order from the object side, a cemented lens of a negative meniscus lens L24 with a convex surface facing the object side and a biconvex lens L25, a cemented lens of a biconvex lens L26 and a biconcave lens L27, and a cemented lens with a concave surface facing the object side. It is composed of a negative meniscus lens L28 that is directed toward the lens. The negative meniscus lens L28 is a composite resin type aspherical lens in which a composite resin film molded into an aspherical shape is attached to the object side surface.

In the zoom lens of Example 6, the first lens group G1 corresponds to the lens group G1 described above. The first sub-a group G1a corresponds to the sub-group G1a described above, and the first sub-b group G1b corresponds to the sub-group G1b described above. The second lens group G2 corresponds to the composite lens group Gn described above. The third lens group G3 corresponds to the composite lens group Gp described above. The fourth lens group G4 corresponds to the lens group Gf described above. The fifth lens group G5 corresponds to the lens group Gr described above. The first lens group G1 and the second lens group G2 correspond to the front group described above. The third lens group G3, the fourth lens group G4, and the fifth lens group G5 correspond to the rear group described above. The sub-group Gv corresponds to the vibration isolation group Gv described above.

The zoom lens of Example 6 performs a zooming operation by changing the distance between adjacent lens groups on the optical axis. During zooming from the wide-angle end to the telephoto end, the first lens group G1 is fixed, the second lens group G2 moves on the optical axis toward the image plane, and the third lens group G3, fourth lens group G4, And the fifth lens group G5 moves on the optical axis toward the object side. During focusing, the fourth lens group G4 moves on the optical axis.

Table 21 is a table of surface data for the zoom lens of Example 6. In Table 21, No. 1 to 7 are surface numbers for the first lens group G1, No. 8 to 15 are surface numbers for the second lens group G2, No. 16 to 35 are surface numbers for the third lens group G3, and No. 23 represents the aperture stop. No. 36 to 38 are surface numbers for the fourth lens group G4, and No. 39 to 47 are surface numbers for the fifth lens group G5.

[Table 21]
Surface number rd nd νd
Object plane ∞ d(0)
1 206.9045 8.7203 1.48749 70.44
2 -535.7473 49.6554
3 124.6420 8.4061 1.49700 81.61
4 -572.0663 0.2000
5 250.4086 7.1255 1.49700 81.61
6 -207.4291 3.0000 1.83481 42.72
7 178.6123 d(7)
8 156.0998 4.1415 1.80518 25.46
9 -713.0123 1.7000 1.69680 55.46
10 137.8420 3.6952
11 -511.1605 4.5915 1.80610 40.73
12 -76.4395 1.5000 1.49700 81.61
13 96.9725 4.9580
14 -78.7377 1.5000 1.83481 42.72
15 413.3270 d(15)
16 63.4940 5.0068 1.61772 49.81
17 405.0584 0.2000
18 43.3956 7.4658 1.49700 81.61
19 -457.8945 0.2001
20 49.6109 7.5057 1.49700 81.61
21 -76.6056 1.5000 1.87070 40.73
22 67.9152 3.9825
23 S ∞ 5.3226
24 -255.0218 3.1532 1.58144 40.89
25 -62.0218 0.2000
26 40.7876 1.2000 1.91082 35.25
27 16.6997 9.3235 1.54814 45.78
28 -28.8101 1.2000 1.83481 42.72
29 152.4120 3.2844
30 -65.0436 3.0216 1.80610 33.27
31 -29.8757 1.1000 1.61772 49.81
32 65.8664 2.2965
33 40.1756 1.2000 1.90366 31.31
34 22.0992 5.4990 1.83400 37.34
35 -148.2010 d(35)
36 -336.2279 3.2525 1.63854 55.38
37 -27.2907 1.0000 1.59282 68.62
38 31.3797 d(38)
39 66.2174 1.1000 1.92286 20.88
40 17.5849 7.0000 1.59270 35.31
41 -41.9820 0.2000
42 58.1086 6.6061 1.75520 27.51
43 -18.2576 1.2000 1.69680 55.46
44 31.5289 5.7900
45 ASPH -19.5266 0.2500 1.53610 41.21
46 -21.2103 1.5000 1.91082 35.25
47 -26.0109 d(47)
Image plane ∞

Table 22 shows a specification table of the zoom lens of Example 6. Table 23 is a table showing aspherical coefficients of each aspherical surface in the zoom lens of Example 6. Table 24 shows the focal length of each lens group constituting the zoom lens of Example 6.

[Table 22]
Wide-angle end Mid-range Telephoto end
f 185.0391 350.1077 582.1701
F No. 5.1488 5.6978 6.5262
ω 6.5076 3.4492 2.0941
Y 21.6330 21.6330 21.6330
Wide-angle end Mid-range Telephoto end Wide-angle end Mid-range Telephoto end
d(0) ∞ ∞ ∞ 2070.5451 2070.5451 2070.5450
d(7) 1.5000 34.1201 50.6036 1.5000 34.1201 50.6036
d(15) 79.2208 35.6007 1.2000 79.2208 35.6007 1.2000
d(35) 2.4965 4.0168 2.5028 5.3012 12.4700 20.9922
d(38) 11.9366 15.3445 23.6215 9.1319 6.8913 5.1322
d(47) 44.5468 50.6186 61.7729 44.5468 50.6186 61.7729

[Table 23]
Surface number k A4 A6
45 0.0000 2.14515E-05 4.16103E-08
Surface number A8 A10 A12
45 3.58278E-10 -7.60201E-13 7.58936E-15

Table 24.
Group Number Focal Length
G1 240.8510
G2 -67.5018
G3 60.0454
G4 -52.1282
G5 -456.0090

[Example 7]
FIG. 25 is a diagram schematically showing the optical configuration of the zoom lens of Example 7 at the wide-angle end when focusing on infinity. 26, 27, and 28 are diagrams showing the longitudinal aberration of the zoom lens of Example 7 at the wide-angle end, intermediate focal length state, and telephoto end when focusing at infinity, respectively. The zoom lens of Example 7 includes, in order from the object side, a first lens group G1 having a positive refractive power, a second lens group G2 having a negative refractive power, and a third lens group G3 having a positive refractive power. , a fourth lens group G4 having negative refractive power, and a fifth lens group G5 having negative refractive power. The first lens group G1 includes a first sub-a group G1a having a positive refractive power and a first sub-b group G1b having a positive refractive power. The third lens group G3 includes a sub-group Gv having negative refractive power. An aperture stop S is arranged within the third lens group G3.

The first lens group G1 is composed of, from the object side, a biconvex lens L1, a cemented lens of a biconvex lens L2 and a biconcave lens L3, and a positive meniscus lens L4 with its convex surface facing the object side. The first sub-a group G1a is composed of lens L1. The first sub-b group G1b is composed of a cemented lens of lens L2 and lens L3, and lens L4.

The second lens group G2 includes, in order from the object side, a cemented lens of a biconvex lens L5 and a biconcave lens L6, a biconcave lens L7, and a biconcave lens L8.

The third lens group G3 is composed of, in order from the object side, a biconvex lens L9, a positive meniscus lens L10 with a convex surface facing the object side, a cemented lens of a biconvex lens L11 and a biconcave lens L12, a biconvex lens L13, a triplet cemented lens of a negative meniscus lens L14 with a convex surface facing the object side, a biconvex lens L15, and a negative meniscus lens L16 with a concave surface facing the object side, a cemented lens of a positive meniscus lens L17 with a concave surface facing the object side and a biconcave lens L18, and a biconvex lens L19. The cemented lens of the lenses L17 and L18 constitutes a subgroup Gv. The subgroup Gv is arranged to be movable in a direction perpendicular to the optical axis so as to correct image blur.

The fourth lens group G4 is composed of a negative meniscus lens L20 with its convex surface facing the object side.

The fifth lens group G5 is composed of, from the object side, a cemented lens of a biconcave lens L21 and a biconvex lens L22, a cemented lens of a biconvex lens L23 and a biconcave lens L24, and a negative meniscus lens L25 with its concave surface facing the object side. The negative meniscus lens L25 is a composite resin type aspherical lens with a composite resin film molded into an aspherical shape attached to the object side surface.

In the zoom lens of Example 7, the first lens group G1 corresponds to the aforementioned lens group G1. The first sub-group a G1a corresponds to the above-mentioned sub-group G1a, and the first sub-group B G1b corresponds to the above-mentioned sub-group G1b. The second lens group G2 corresponds to the above-mentioned composite lens group Gn. The third lens group G3 corresponds to the above-mentioned composite lens group Gp. The fourth lens group G4 corresponds to the aforementioned lens group Gf. The fifth lens group G5 corresponds to the above-mentioned lens group Gr. The first lens group G1 and the second lens group G2 correspond to the above-mentioned front group. The third lens group G3, the fourth lens group G4, and the fifth lens group G5 correspond to the aforementioned rear group. The sub-group Gv corresponds to the above-mentioned anti-vibration group Gv.

The zoom lens of Example 7 performs a magnification change operation by changing the distance on the optical axis between adjacent lens groups. When changing magnification from the wide-angle end to the telephoto end, the second lens group G2 moves on the optical axis toward the image surface, and the first lens group G1, the third lens group G3, the fourth lens group G4, and the fifth lens group G5 move on the optical axis toward the object side. When focusing, the fourth lens group G4 moves on the optical axis.

Table 25 is a table of surface data for the zoom lens of Example 7. In Table 25, No. 1 to 7 are surface numbers of the first lens group G1, No. 8 to 14 are surface numbers of the second lens group G2, No. 15 to 33 are surface numbers of the third lens group G3, and No. 22 represents the aperture stop. No. 34 and 35 are surface numbers of the fourth lens group G4. No. 36 to 44 are surface numbers of the fifth lens group G5.

[Table 25]
Surface number rd nd νd
Object plane ∞ d(0)
1 172.3802 10.0000 1.48749 70.44
2 -466.0819 26.4680
3 169.8051 9.2897 1.49700 81.61
4 -263.4463 2.5000 1.83481 42.72
5 226.0306 3.0000
6 180.5266 5.8396 1.49700 81.61
7 49261.6741 d(7)
8 82.5925 7.1450 1.80610 33.27
9 -135.3569 1.5000 1.48749 70.44
10 61.2463 4.5401
11 -410.1487 1.7000 1.80420 46.50
12 141.4302 3.9575
13 -94.4441 1.5000 1.83481 42.72
14 141.7533 d(14)
15 127.1737 3.9110 1.80518 25.46
16 -374.1390 0.2000
17 48.9558 5.7404 1.49700 81.61
18 1105.3240 0.2000
19 44.0541 7.9860 1.49700 81.61
20 -116.7261 1.5000 1.83400 37.34
21 63.0332 3.9536
22 S ∞ 9.4153
23 393.3859 3.2093 1.60562 43.71
24 -86.2503 0.2319
25 62.1900 1.2000 2.00069 25.46
26 20.5654 7.9590 1.51823 58.96
27 -34.5551 1.2000 1.83481 42.72
28 -413.5774 2.3360
29 -130.1270 3.0678 1.80610 33.27
30 -40.6450 1.1000 1.63930 44.87
31 64.9719 2.3553
32 44.8910 4.5000 1.80518 25.46
33 -194.2508 d(33)
34 126.1060 1.0000 1.59282 68.62
35 31.5877 d(35)
36 -73.0143 1.1000 1.92286 20.88
37 25.5204 7.5632 1.68893 31.16
38 -37.0338 0.7000
39 82.9678 7.9111 1.75211 25.05
40 -22.7677 1.2000 1.59282 68.62
41 87.6639 5.6099
42 ASPH -30.6150 0.2500 1.53610 41.21
43 -33.0113 1.5000 1.87070 40.73
44 -59.9951 d(44)
Image plane ∞

Table 26 shows a specification table of the zoom lens of Example 7. Table 27 is a table showing aspherical coefficients of each aspherical surface in the zoom lens of Example 7. Table 28 shows the focal length of each lens group constituting the zoom lens of Example 7.

[Table 26]
Wide-angle end Intermediate Telephoto end
f 184.9891 350.0115 582.1094
FNo. 5.8025 6.1007 6.5255
ω 6.6295 3.5092 2.1242
Y 21.6330 21.6330 21.6330
Wide-angle end Intermediate Telephoto end Wide-angle end Intermediate Telephoto end
d(0) ∞ ∞ ∞ 2100.5451 2087.7170 2072.8528
d(7) 1.5000 37.4228 59.2326 1.5000 37.4228 59.2326
d(14) 58.2807 25.1860 1.2000 58.2807 25.1860 1.2000
d(33) 7.9909 10.7393 3.0058 11.4266 21.7301 25.4774
d(35) 30.7812 19.2814 29.2251 27.3455 8.2906 6.7535
d(44) 36.5625 55.3140 70.1441 36.5625 55.3140 70.1441

[Table 27]
Surface number k A4 A6
42 0.0000 7.87716E-06 -1.01553E-09
Surface number A8 A10 A12
42 8.18662E-11 -2.73250E-13 5.01859E-16

[Table 28]
Group number Focal length
G1 220.1850
G2 -60.7037
G3 59.2832
G4 -71.3715
G5 -255.4510

[Example 8]
Fig. 29 is a diagram showing the optical configuration of the zoom lens of Example 8 at the wide-angle end when focusing on infinity. Figs. 30, 31, and 32 are diagrams showing longitudinal aberrations of the zoom lens of Example 8 at the wide-angle end, the intermediate focal length state, and the telephoto end when focusing on infinity, respectively. The zoom lens of Example 8 is composed of, in order from the object side, a first lens group G1 having positive refractive power, a second lens group G2 having negative refractive power, a third lens group G3 having positive refractive power, a fourth lens group G4 having negative refractive power, a fifth lens group G5 having negative refractive power, and a sixth lens group G6 having positive refractive power. The first lens group G1 includes a first sub-a group G1a having positive refractive power and a first sub-b group G1b having positive refractive power. The third lens group G3 includes a sub-group Gv having negative refractive power. An aperture stop S is arranged in the third lens group G3.

The first lens group G1 includes, in order from the object side, a biconvex lens L1, a biconvex lens L2, and a cemented lens of a biconvex lens L3 and a biconcave lens L4. The first sub-a group G1a is composed of a lens L1. The first sub-b group G1b is composed of a cemented lens of a lens L2 and a lens L3, and a lens L4.

The second lens group G2 is composed of, in order from the object side, a cemented lens of a positive meniscus lens L5 with a convex surface facing the object side and a negative meniscus lens L6 with a convex surface facing the object side, a cemented lens of a positive meniscus lens L7 with a concave surface facing the object side and a biconcave lens L8, and a biconcave lens L9.

The third lens group G3 includes, in order from the object side, a biconvex lens L10, a biconvex lens L11, a cemented lens of a biconvex lens L12 and a biconcave lens L13, a biconvex lens L14, and a negative meniscus lens with a convex surface facing the object side. A three-piece cemented lens of L15, a biconvex lens L16, and a biconcave lens L17, a cemented lens of a positive meniscus lens L18 and a biconcave lens L19 with a concave surface facing the object side, and a negative meniscus lens L20 with a convex surface facing the object side. It is composed of a cemented lens with a biconvex lens L21. The cemented lens of lenses L18 and L19 constitutes a sub-group Gv. The sub group Gv is arranged so as to be movable in a direction perpendicular to the optical axis so as to correct image blur.

The fourth lens group G4 is composed of, in order from the object side, a cemented lens consisting of a positive meniscus lens L22 with its concave surface facing and a biconcave lens L23.

The fifth lens group G5 includes, in order from the object side, a cemented lens of a negative meniscus lens L24 with a convex surface facing the object side and a biconvex lens L25, a cemented lens of a biconvex lens L26 and a biconcave lens L27, and a cemented lens with a concave surface facing the object side. It is composed of a negative meniscus lens L28 that is directed toward the lens. The negative meniscus lens L28 is a composite resin type aspherical lens in which a composite resin film molded into an aspherical shape is attached to the object side surface.

The sixth lens group G6 is composed of a biconvex lens L29.

In the zoom lens of Example 8, the first lens group G1 corresponds to the aforementioned lens group G1. The first sub-group a G1a corresponds to the above-mentioned sub-group G1a, and the first sub-group B G1b corresponds to the above-mentioned sub-group G1b. The second lens group G2 corresponds to the above-mentioned composite lens group Gn. The third lens group G3 corresponds to the above-mentioned composite lens group Gp. The fourth lens group G4 corresponds to the aforementioned lens group Gf. The fifth lens group G5 corresponds to the above-mentioned lens group Gr. The first lens group G1 and the second lens group G2 correspond to the above-mentioned front group. The third lens group G3, the fourth lens group G4, the fifth lens group G5, and the sixth lens group G6 correspond to the aforementioned rear group. The sub-group Gv corresponds to the above-mentioned anti-vibration group Gv.

The zoom lens of Example 8 performs a magnification change operation by changing the distance on the optical axis between adjacent lens groups. When changing magnification from the wide-angle end to the telephoto end, the first lens group G1 and the sixth lens group are fixed, the second lens group G2 moves on the optical axis toward the image surface, and the third lens group G3, the fourth lens group G4, and the fifth lens group G5 move on the optical axis toward the object side. When focusing, the fourth lens group G4 moves on the optical axis.

Table 29 is a table of surface data of the zoom lens of Example 8. In Table 29, No. 1 to 7 are surface numbers of the first lens group G1; 8 to 15 are surface numbers of the second lens group G2. No. 16 to 35 are surface numbers of the third lens group G3; 23 represents an aperture stop. No. 36 to 38 are surface numbers of the fourth lens group G4; 39 to 47 are surface numbers of the fifth lens group G5. 48 and 49 are surface numbers of the sixth lens group G6.

[Table 29]
Surface number rd nd νd
Object plane ∞ d(0)
1 167.0051 9.7717 1.48749 70.44
2 -581.8001 34.0529
3 148.0607 7.1345 1.49700 81.61
4 -1998.0634 0.2000
5 174.2255 8.0845 1.49700 81.61
6 -256.0406 3.0000 1.83481 42.72
7 155.6926 d(7)
8 75.6673 4.6247 1.80000 29.84
9 199.9490 1.7000 1.69680 55.46
10 60.4735 6.2405
11 -345.8231 4.4881 1.80100 34.97
12 -74.2304 1.5000 1.49700 81.61
13 132.9156 4.4201
14 -81.6451 1.5000 1.83481 42.72
15 718.4249 d(15)
16 167.0711 3.5462 1.60562 43.71
17 -668.6218 0.2000
18 50.3092 7.7533 1.49700 81.61
19 -173.3638 0.5194
20 48.5962 8.6061 1.49700 81.61
21 -80.9143 1.5000 1.87070 40.73
22 105.0696 7.2411
23 S ∞ 7.2229
24 2060.6500 4.0000 1.58144 40.75
25 -85.3052 0.2000
26 49.3627 1.2030 1.91082 35.25
27 17.6896 8.3492 1.54072 47.23
28 -32.2886 1.2000 1.83481 42.72
29 109.3314 3.3144
30 -72.6032 3.0427 1.80610 33.27
31 -31.7214 1.1000 1.61772 49.81
32 72.3530 2.2001
33 45.2497 1.2000 1.90366 31.31
34 27.7950 5.0000 1.83400 37.34
35 -109.1425 d(35)
36 -2448.6513 3.1258 1.63854 55.38
37 -31.9909 1.0000 1.59282 68.62
38 32.0214 d(38)
39 70.0871 1.1000 1.92286 20.88
40 20.0006 7.0000 1.59270 35.31
41 -58.4669 0.2000
42 35.5361 6.8580 1.75520 27.51
43 -27.4922 1.2000 1.69680 55.46
44 24.6912 6.1109
45 ASPH -33.6516 0.1500 1.53610 41.21
46 -47.0817 1.5000 1.83481 42.72
47 -178.1352 d(47)
48 156.1964 5.2414 1.51680 64.20
49 -83.7431 d(49)
Image plane ∞

Table 30 shows a specification table of the zoom lens of Example 8. Table 31 is a table showing aspherical coefficients of each aspherical surface in the zoom lens of Example 8. Table 32 shows the focal length of each lens group constituting the zoom lens of Example 8.

[Table 30]
Wide-angle end Intermediate Telephoto end
f 185.0202 350.0371 582.2048
FNo. 5.1485 5.6965 6.5266
ω 6.5165 3.4560 2.0986
Y 21.6330 21.6330 21.6330
Wide-angle end Intermediate Telephoto end Wide-angle end Intermediate Telephoto end
d(0) ∞ ∞ ∞ 2070.5452 2070.5451 2070.5452
d(7) 5.3690 38.3171 52.9577 5.3690 38.3171 52.9577
d(15) 80.4177 36.4695 1.2000 80.4177 36.4695 1.2000
d(35) 2.4976 4.2781 3.6043 5.9892 14.5841 25.3710
d(38) 19.2638 18.5798 28.0910 15.7722 8.2737 6.3243
d(47) 4.8505 14.7541 26.5456 4.8505 14.7541 26.5456
d(49) 29.4548 29.4548 29.4548 29.4548 29.4548 29.4548

Table 31.
Face number k A4 A6
45 0.0000 1.53321E-05 3.36775E-08
Face number A8 A10 A12
45 -4.71209E-11 1.01485E-12 -1.13213E-15

[Table 32]
Group number Focal length
G1 245.7150
G2 -70.4455
G3 65.0983
G4 -57.6700
G5 -110.0000
G6 106.2780

The values calculated using the above formulas in Examples 1 to 8 and the numerical values used in the formulas are shown in Table 33.

Table 33.
Example 1 Example 2 Example 3 Example 4
Formula (1) fr/ft -0.375 -0.445 -0.364 -0.838
Equation (2) βrt/βrw 1.084 1.086 1.090 1.035
Equation (3) Xp/(-Xn) 0.427 0.660 0.481 0.539
Equation (4) |fv|/fpt 1.391 1.499 1.371 0.978
Equation (5) Lt/ft 0.566 0.566 0.566 0.566
Equation (6) |{1-(βft) ² }×(βcrt) ² | 7.459 7.745 7.565 7.690
Equation (7) ΔPgF1 -0.0067 -0.0067 -0.0067 -0.0067
Equation (8) ΔPgFr 0.0283 0.0283 0.0283 0.0283
Equation (9) fpt/ft 0.104 0.099 0.105 0.111
Equation (10) f1/fw 1.260 1.160 1.161 1.402
Equation (11) f1/ft 0.400 0.369 0.369 0.446
Equation (12) BFw/Yw 2.247 2.121 2.229 2.117
Example 5 Example 6 Example 7 Example 8
Equation (1) fr/ft -0.581 -0.783 -0.439 -0.189
Equation (2) βrt/βrw 1.051 1.038 1.113 1.150
Equation (3) Xp/(-Xn) 0.518 0.589 0.900 0.665
Equation (4) |fv|/fpt 1.032 1.070 1.405 1.115
Equation (5) Lt/ft 0.566 0.566 0.562 0.566
Equation (6) |{1-(βft) ² }×(βcrt) ² | 7.062 9.124 7.765 7.892
Equation (7) ΔPgF1 -0.0067 -0.0067 -0.0067 -0.0067
Equation (8) ΔPgFr 0.0283 0.0283 0.0283 0.0283
Equation (9) fpt/ft 0.113 0.103 0.102 0.112
Equation (10) f1/fw 1.277 1.302 1.190 1.328
Equation (11) f1/ft 0.406 0.414 0.378 0.422
Equation (12) BFw/Yw 1.996 2.059 1.690 1.362
Example 1 Example 2 Example 3 Example 4
BFw 48.611 45.875 48.219 45.800
f1 233.028 214.642 214.695 259.472
fr -218.296 -258.837 -211.827 -488.016
βrt 1.371 1.418 1.424 1.027
βrw 1.265 1.305 1.307 0.992
fv -84.165 -86.235 -83.718 -63.414
fpt 60.517 57.518 61.082 64.843
Lt 329.455 329.455 329.455 329.455
βft 2.229 2.203 2.175 2.880
βcrt 1.371 1.418 1.424 1.027
Xp 23.305 29.192 24.979 29.168
Xn -54.642 -44.251 -51.880 -54.078
Example 5 Example 6 Example 7 Example 8
BFw 43.170 44.547 36.563 29.455
f1 236.317 240.851 220.185 245.715
fr -338.215 -456.009 -255.451 -110.000
βrt 1.080 1.039 1.295 1.503
βrw 1.027 1.002 1.163 1.307
fv -67.752 -64.235 -83.303 -72.570
fpt 65.626 60.045 59.283 65.098
Lt 329.455 329.455 327.147 329.455
βft 2.657 3.074 2.373 2.809
βcrt 1.080 1.039 1.295 1.070
Xp 26.764 28.917 27.040 31.629
Xn -51.710 -49.103 -30.040 -47.589

REFERENCE SIGNS LIST 1 mirrorless single-lens camera 2 body 3 lens barrel 21 CCD sensor 30 zoom lens 31, G1 first lens group 31a first sub-a group 31b first sub-b group 32 second lens group (composite lens group Gn)
33 third lens group (composite lens group Gp)
33v Sub-group (vibration control group Gv)
34 Fourth lens group (lens group Gf)
35 Fifth lens group (lens group Gr)
36, S Aperture stop OA Optical axis

Claims (11)

The lens has, in order from the object side, a front group having negative refractive power and a rear group having positive refractive power;
the front group includes, as a lens group and a composite lens group, in that order from the object side, a lens group G1 having a positive refractive power and a composite lens group Gn having a negative refractive power,
the rear group includes, in order from the object side, a composite lens group Gp having positive refractive power and a lens group Gf having negative refractive power;
the rear group further includes a lens group Gr having a negative refractive power located closer to the image surface than the lens group Gf,
The composite lens group Gn has one or more lens groups,
The composite lens group Gp has one or more lens groups,
When the magnification is changed between the wide-angle end and the telephoto end, the distance on the optical axis between the adjacent lens groups changes, and the lens group G1 is fixed.
When changing magnification from the wide-angle end to the telephoto end, the lens group Gr moves toward the object side on the optical axis,
During focusing, the lens group Gf moves along the optical axis,
A zoom lens that satisfies the following formula:
−0.90≦fr/ft≦−0.03 (1)
1.01≦βrt/βrw≦1.50 (2)
however,
fr: focal length of the lens group Gr, ft: focal length of the zoom lens at the telephoto end when focused on infinity, βrt: lateral magnification of the lens group Gr at the telephoto end when focused on infinity, βrw: lateral magnification of the lens group Gr at the wide-angle end when focused on infinity. The zoom lens according to claim 1, which satisfies the following formula.
Xp/(-Xn)≦1.0 (3)
however,
Xn: Amount of movement from the wide-angle end to the telephoto end of the lens group having at least one negative refractive power included in the composite lens group Gn. Xp: The lens group having at least one positive refractive power included in the composite lens group Gp. Amount of movement from wide-angle end to telephoto end The composite lens group Gp has a vibration isolation group Gv that has negative refractive power and moves in a direction perpendicular to the optical axis to correct image blur,
The zoom lens according to claim 1, which satisfies the following formula.
0.65≦|fv|/fpt≦2.00 (4)
however,
fv: Focal length of the image stabilization group Gv fpt: Focal length of the composite lens group Gp at the telephoto end 2. The zoom lens of claim 1, wherein the following formula is satisfied:
0.35≦Lt/ft≦0.70 (5)
however,
Lt: total optical length of the zoom lens at the telephoto end when focused on infinity The zoom lens according to claim 1, which satisfies the following formula.
5.0≦｜{1-(βft) ² }×(βcrt) ² |≦13.0・・・・・・(6)
however,
βft: Lateral magnification at the telephoto end when the lens group Gf is focused at infinity βcrt: Lateral magnification at the telephoto end when all lens groups on the image plane side than the lens group Gf are focused at infinity The lens group G1 includes one or more lenses having negative refractive power,
The zoom lens according to claim 1, which satisfies the following formula.
-0.012≦ΔPgF1≦-0.001 (7)
however,
ΔPgF1: anomalous dispersion of at least one lens having negative refractive power included in the lens group G1 2. The zoom lens of claim 1, wherein the following formula is satisfied:
0.015≦ΔPgFr≦0.050 (8)
however,
ΔPgFr: anomalous dispersion of at least one lens having negative refractive power included in the lens group Gr 2. The zoom lens of claim 1, wherein the following formula is satisfied:
0.05≦fpt/ft≦0.20 (9)
however,
fpt: focal length of the composite lens group Gp at the telephoto end 2. The zoom lens of claim 1, wherein the following formula is satisfied:
0.40≦f1/fw≦3.00 (10)
however,
f1: focal length of the lens group G1 fw: focal length of the zoom lens at the wide-angle end when focused on infinity The zoom lens according to claim 1, which satisfies the following formula.
0.28≦f1/ft≦0.55 (11)
however,
f1: Focal length of the lens group G1 An imaging device comprising the zoom lens according to any one of claims 1 to 10, and an image sensor provided on the image plane side of the zoom lens, which converts an optical image formed by the zoom lens into an electrical signal.

Images