JP2019074760A - Zoom lens - Google Patents

Abstract

To provide a zoom lens which offers a bright F-number and high optical performance.SOLUTION: A zoom lens comprises, in order from the object side along an optical axis, a first lens group G1 having negative 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, and a fifth lens group G5. Distance between each pair of adjacent lens groups changes in variable magnification. At least some lenses of the first through fifth lens groups are configured to be movable in a direction having a directional component perpendicular to the optical axis. The fifth lens group includes a meniscus-shaped positive lens which has a convex surface facing the image side and satisfies a condition expressed as: 1.100<(r1+r2)/(r1-r2)<5.000, where r1 represents a curvature radius of an object-side surface of the positive lens, and r2 represents a curvature radius of the image-side surface of the positive lens.SELECTED DRAWING: Figure 1

Description

The present invention relates to a zoom lens suitable for photographic cameras, electronic still cameras, video cameras and the like.
Priority is claimed on Japanese Patent Application No. 2015-01721, filed Jan. 30, 2015, the content of which is incorporated herein by reference.

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

JP 2007-279077

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

According to one aspect of the present invention, a first lens group having negative refractive power, a second lens group having positive refractive power, and a third lens having negative refractive power are arranged in order from the object side along the optical axis. And a fourth lens group having a positive refractive power, and a fifth lens group, and during zooming, a distance between the first lens group and the second lens group changes, and the second lens group The distance between the lens group and the third lens group changes, the distance between the third lens group and the fourth lens group changes, and the distance between the fourth lens group and the fifth lens group changes Of the first to fifth lens groups, at least a part of the lenses is configured to be movable so as to include a component in a direction orthogonal to the optical axis, and the fifth lens group is disposed on the image side Provided is a zoom lens having a positive meniscus lens with a convex surface, and satisfying the following conditional expression.
1.100 <(r1 + r2) / (r1-r2) <5.000
However,
r1: radius of curvature of the object-side surface of the positive lens r2: radius of curvature of the image-side surface of the positive lens

FIGS. 1A, 1B, and 1C are cross-sectional views of the zoom lens according to the first embodiment at the wide-angle end, at an intermediate focal length, and at the telephoto end, respectively. 2 (a), 2 (b) and 2 (c) show the zoom lens according to the first embodiment at the time of focusing on an infinity object in the wide-angle end state, the intermediate focal length state and the telephoto end state, respectively. FIG. 3 (a), 3 (b), and 3 (c) show the zoom lens according to the first embodiment at the time of near-field object focusing in the wide-angle end state, the intermediate focal length state, and the telephoto end state, respectively. FIG. 4 (a), 4 (b) and 4 (c) respectively show the meridional horizontal at the time of image stabilization in the wide-angle end state, the intermediate focal length state and the telephoto end state of the zoom lens according to the first embodiment. FIG. FIGS. 5A, 5B, and 5C are cross-sectional views of the zoom lens according to the second embodiment at the wide-angle end, at the intermediate focal length, and at the telephoto end, respectively. 6 (a), 6 (b), and 6 (c) show the zoom lens according to the second embodiment at the time of focusing on an infinite object in the wide-angle end state, the intermediate focal length state, and the telephoto end state, respectively. FIG. FIGS. 7A, 7B, and 7C show the zoom lens according to the second embodiment at the time of near distance object focusing in the wide-angle end state, the intermediate focal length state, and the telephoto end state, respectively. FIG. 8 (a), 8 (b), and 8 (c) show the meridional horizontal at the time of image stabilization in the wide-angle end state, the intermediate focal length state, and the telephoto end state of the zoom lens according to the second embodiment, respectively. FIG. FIGS. 9A, 9B, and 9C are cross-sectional views of the zoom lens according to the third embodiment in the wide-angle end state, in the intermediate focal length state, and in the telephoto end state, respectively. 10 (a), 10 (b), and 10 (c) show the zoom lens according to the third embodiment at the time of focusing on an infinity object in the wide-angle end state, the intermediate focal length state, and the telephoto end state, respectively. FIG. 11 (a), 11 (b) and 11 (c) show the zoom lens according to the third embodiment at the time of near-field focusing in the wide-angle end state, the intermediate focal length state and the telephoto end state, respectively. FIG. 12 (a), 12 (b) and 12 (c) show the meridional horizontal at the time of image stabilization in the wide-angle end state, the intermediate focal length state and the telephoto end state of the zoom lens according to the third embodiment, respectively. FIG. FIGS. 13A, 13B, and 13C are cross-sectional views of the zoom lens according to the fourth example at the wide-angle end, at an intermediate focal length, and at the telephoto end, respectively. FIGS. 14 (a), 14 (b) and 14 (c) show the zoom lens according to the fourth embodiment at the time of focusing on an infinity object in the wide-angle end state, the intermediate focal length state and the telephoto end state, respectively. FIG. FIGS. 15 (a), 15 (b) and 15 (c) show the zoom lens according to the fourth embodiment at the time of near object focusing in the wide-angle end state, the intermediate focal length state and the telephoto end state, respectively. FIG. 16 (a), 16 (b) and 16 (c) show the meridional horizontal at the time of image stabilization in the wide-angle end state, the intermediate focal length state and the telephoto end state of the zoom lens according to the fourth embodiment, respectively. FIG. FIGS. 17A, 17B, and 17C are cross-sectional views of the zoom lens according to the fifth embodiment at the wide-angle end, at the intermediate focal length, and at the telephoto end, respectively. 18 (a), 18 (b) and 18 (c) show the zoom lens according to the fifth embodiment at the time of focusing on an infinity object in the wide-angle end state, the intermediate focal length state and the telephoto end state, respectively. FIG. 19 (a), 19 (b), and 19 (c) show the zoom lens according to the fifth embodiment at the time of near-field object focusing in the wide-angle end state, the intermediate focal length state, and the telephoto end state, respectively. FIG. 20 (a), 20 (b), and 20 (c) show the meridional horizontal at the time of image stabilization in the wide-angle end state, the intermediate focal length state, and the telephoto end state of the zoom lens according to the fifth example, respectively. FIG. FIGS. 21 (a), 21 (b) and 21 (c) are cross-sectional views of the zoom lens according to the sixth embodiment at the wide-angle end, at the intermediate focal length, and at the telephoto end, respectively. 22 (a), 22 (b), and 22 (c) show the zoom lens according to the sixth embodiment at the time of focusing on an infinity object in the wide-angle end state, the intermediate focal length state, and the telephoto end state, respectively. FIG. FIGS. 23 (a), 23 (b) and 23 (c) show the zoom lens according to the sixth embodiment at the time of near object focusing in the wide-angle end state, the intermediate focal length state and the telephoto end state, respectively. FIG. FIGS. 24 (a), 24 (b) and 24 (c) show the meridional horizontal at the time of image stabilization in the wide-angle end state, the intermediate focal length state and the telephoto end state of the zoom lens according to the sixth embodiment, respectively. FIG. FIGS. 25 (a), 25 (b) and 25 (c) are cross-sectional views of the zoom lens according to the seventh embodiment at the wide-angle end, at the intermediate focal length, and at the telephoto end, respectively. 26 (a), 26 (b), and 26 (c) show the zoom lens according to the seventh embodiment at the time of focusing on an infinity object in the wide-angle end state, the intermediate focal length state, and the telephoto end state, respectively. FIG. 27 (a), 27 (b) and 27 (c) show the zoom lens according to the seventh embodiment at the time of near distance object focusing in the wide-angle end state, the intermediate focal length state and the telephoto end state, respectively. FIG. 28 (a), 28 (b) and 28 (c) show the meridional horizontal at the time of image stabilization in the wide-angle end state, the intermediate focal length state and the telephoto end state of the zoom lens according to the seventh embodiment, respectively. FIG. FIGS. 29A, 29B, and 29C are cross-sectional views of the zoom lens according to the eighth embodiment in the wide-angle end state, in the intermediate focal length state, and in the telephoto end state, respectively. 30 (a), 30 (b), and 30 (c) show the zoom lens according to the eighth embodiment at the time of focusing on an infinity object in the wide-angle end state, the intermediate focal length state, and the telephoto end state, respectively. FIG. 31 (a), 31 (b), and 31 (c) show the zoom lens according to the eighth embodiment at the time of near-field object focusing in the wide-angle end state, the intermediate focal length state, and the telephoto end state, respectively. FIG. 32 (a), 32 (b), and 32 (c) show the meridional horizontal at the time of image stabilization in the wide-angle end state, the intermediate focal length state, and the telephoto end state of the zoom lens according to the eighth embodiment, respectively. FIG. FIGS. 33A, 33B, and 33C are cross-sectional views of the zoom lens according to the ninth embodiment in the wide-angle end state, in the intermediate focal length state, and in the telephoto end state, respectively. 34 (a), 34 (b) and 34 (c) show the zoom lens according to the ninth embodiment at the time of focusing on an infinity object in the wide-angle end state, the intermediate focal length state and the telephoto end state, respectively. FIG. 35 (a), 35 (b) and 35 (c) show the zoom lens according to the ninth embodiment at the time of near object focusing in the wide-angle end state, the intermediate focal length state and the telephoto end state, respectively. FIG. 36 (a), 36 (b) and 36 (c) show the meridional horizontal at the time of image stabilization in the wide-angle end state, the intermediate focal length state and the telephoto end state of the zoom lens according to the ninth embodiment, respectively. FIG. FIGS. 37A, 37B, and 37C are cross-sectional views of the zoom lens according to Example 10 at the wide-angle end, at the intermediate focal length, and at the telephoto end, respectively. 38 (a), 38 (b) and 38 (c) show the zoom lens according to Example 10 when focusing on an infinity object in the wide-angle end state, in the intermediate focal length state and in the telephoto end state, respectively. FIG. 39 (a), 39 (b), and 39 (c) show the zoom lens according to Example 10 when focusing on a short distance at the wide-angle end, at the intermediate focal length, and at the telephoto end, respectively. FIG. 40 (a), 40 (b) and 40 (c) show the meridional horizontal at the time of image stabilization in the wide-angle end state, the intermediate focal length state and the telephoto end state of the zoom lens according to the tenth embodiment, respectively. FIG. 41 (a), 41 (b), and 41 (c) are cross-sectional views of the zoom lens according to Example 11 at the wide-angle end, at the intermediate focal length, and at the telephoto end, respectively. 42 (a), 42 (b) and 42 (c) show the zoom lens according to Example 11 when focusing on an infinity object in the wide-angle end state, in the intermediate focal length state and in the telephoto end state, respectively. FIG. 43 (a), 43 (b) and 43 (c) show the zoom lens according to Example 11 when focusing on a near object in the wide-angle end state, in the intermediate focal length state and in the telephoto end state, respectively. FIG. 44 (a), 44 (b) and 44 (c) respectively show the meridional horizontal at the time of image stabilization in the wide-angle end state, the intermediate focal length state and the telephoto end state of the zoom lens according to Example 11. FIG. FIG. 45 is a schematic view showing the configuration of a camera provided with a zoom lens. FIG. 46 is a diagram schematically showing a method of manufacturing a zoom lens.

  Hereinafter, a zoom lens, an optical device, and a method of manufacturing the zoom lens will be described in the embodiment. First, the zoom lens according to an embodiment will be described.

The zoom lens according to one embodiment includes, in order from the object side along the optical axis, a first lens group having negative refractive power, a second lens group having positive refractive power, and a second lens group having negative refractive power. The zoom lens has a third lens group, a fourth lens group having a positive refracting power, and a fifth lens group, and during zooming, the distance between the first lens group and the second lens group changes. The distance between the second lens group and the third lens group changes, the distance between the third lens group and the fourth lens group changes, and the distance between the fourth lens group and the fifth lens group is The first lens group to the fifth lens group are configured to be movable so as to include a component in a direction orthogonal to the optical axis among the first lens group to the fifth lens group, and the fifth lens group is configured to It has a positive meniscus lens with a convex surface on the side. In one example, the fifth lens group can have positive refractive power.
With this configuration, it is possible to realize zooming and to achieve good aberration correction at the time of zooming. In addition, good aberration correction can be achieved even at the time of image stabilization.

The zoom lens satisfies the following conditional expression (1).
(1) 1.100 <(r1 + r2) / (r1-r2) <5.000
However,
r1: radius of curvature of the object-side surface of the positive lens r2: radius of curvature of the image-side surface of the positive lens

  The conditional expression (1) is a conditional expression for defining the form factor of the positive lens in the fifth lens group. By satisfying the conditional expression (1), it is possible to realize brightness with an F number of about F2.8 to F4.0 while being wide-angle, and to correct various aberrations including spherical aberration well.

  When the corresponding value of the conditional expression (1) exceeds the upper limit value, the power of the positive lens is reduced, and the magnification change load of lenses other than the positive lens in the fifth lens group or the fifth lens group is not used. The magnification change burden of the lens group of In particular, as the power of the fourth lens unit increases, it may be difficult to correct coma. In order to secure the effect, it is preferably possible to set the upper limit of conditional expression (1) to 4.200. In order to further ensure the effect, it is preferable that the upper limit value of the conditional expression (1) be 3.400.

  On the other hand, when the corresponding value of the conditional expression (1) falls below the lower limit value, the power of the positive lens is increased, and the declination of the off-axis ray passing through the positive lens is increased. It can be difficult. In order to secure the effect, it is preferable that the lower limit value of conditional expression (1) be 1.400. In order to further ensure the effect, it is preferable that the lower limit value of the conditional expression (1) be 1.700.

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

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

  When the corresponding value of the conditional expression (2) exceeds the upper limit, the distance between the first lens unit and the image plane increases, and in particular, the burden of spherical aberration and coma aberration correction on the second lens unit increases. It may be difficult to correct spherical aberration and coma. In order to secure the effect, it is preferable that the upper limit value of conditional expression (2) be 4.000. Further, in order to further ensure the effect, it is preferable that the upper limit value of the conditional expression (2) be 3.000.

  On the other hand, when the corresponding value of the conditional expression (2) falls below the lower limit value, the magnification change load of the lens units other than the first lens unit increases, and in particular, the power of the fourth lens unit increases. Correction may be difficult. In order to secure the effect, it is preferable that the lower limit value of conditional expression (2) be 0.600. Further, in order to further ensure the effect, it is preferable that the lower limit value of the conditional expression (2) be 0.900.

Moreover, it is preferable that the zoom lens can satisfy the following conditional expression (3).
(3) 0.200 <f5 / f4 <4.000
However,
f5: focal length of the fifth lens group f4: focal length of the fourth lens group

  Conditional expression (3) is a conditional expression for defining an appropriate range of the ratio of the focal length of the fifth lens unit to the focal length of the fourth lens unit. If the corresponding value of the conditional expression (3) exceeds the upper limit value, the power of the fourth lens group with respect to the fifth lens group will increase, which may make it difficult to correct coma. In order to secure the effect, it is preferable that the upper limit value of conditional expression (3) be 3.300. Further, in order to further ensure the effect, it is preferable that the upper limit value of the conditional expression (3) be 2.600.

  On the other hand, if the corresponding value of the conditional expression (3) falls below the lower limit value, the power of the fifth lens group with respect to the fourth lens group will increase, which may make it difficult to correct field curvature. In order to secure the effect, it is preferable that the lower limit value of conditional expression (3) be 0.350. In order to further ensure the effect, it is preferable that the lower limit value of conditional expression (3) be 0.450.

Further, it is preferable that the zoom lens be configured to be movable so that at least a part of the lenses in the third lens group include components in a direction orthogonal to the optical axis. For example, the zoom lens can preferably be configured to be movable so that at least two lenses in the third lens group include components in a direction orthogonal to the optical axis.
As described above, by configuring at least two lenses in the third lens group to be movable as a vibration reduction lens group so as to include a component in a direction orthogonal to the optical axis, the size of the vibration reduction lens group can be reduced. Further, decentration coma aberration, decentration field curvature, and decentering magnification chromatic aberration at the time of image stabilization can be well corrected.

Preferably, the zoom lens can be configured to be movable so that at least a part of the lenses in the second lens group includes a component in a direction orthogonal to the optical axis. For example, the zoom lens can preferably be configured to be movable so that at least two lenses in the second lens group include components in a direction orthogonal to the optical axis.
As described above, by configuring so that at least two lenses in the second lens group can be moved as a vibration reduction lens group so as to include a component in a direction orthogonal to the optical axis, the vibration reduction lens group can be miniaturized. Further, decentration coma aberration, decentration field curvature, and decentering magnification chromatic aberration at the time of image stabilization can be well corrected.

In the zoom lens, preferably, at least a part of the lenses in the fourth lens group can be moved so as to include a component in a direction orthogonal to the optical axis. For example, it is preferable that the zoom lens be configured to be movable so that at least two lenses in the fourth lens group include components in a direction orthogonal to the optical axis.
As described above, by configuring so that at least two lenses in the fourth lens group can be moved as a vibration reduction lens group so as to include a component in a direction orthogonal to the optical axis, the vibration reduction lens group can be miniaturized. Further, decentration coma aberration, decentration field curvature, and decentering magnification chromatic aberration at the time of image stabilization can be well corrected.

The zoom lens is preferably capable of focusing from an infinite distance object to a near distance object by moving at least a part of lenses in the second lens group along the optical axis. For example, the zoom lens is preferably capable of focusing from an infinite distance object to a near distance object by moving at least two lenses in the second lens group along the optical axis.
With this configuration, downsizing of the focusing lens unit can be realized, and fluctuation of chromatic aberration and fluctuation of curvature of field due to focusing can be corrected well.

The zoom lens is preferably capable of focusing from an infinite distance object to a near distance object by moving at least a part of lenses in the third lens group along the optical axis. For example, the zoom lens is preferably capable of focusing from an infinite distance object to a near distance object by moving at least two lenses in the third lens group along the optical axis.
With this configuration, downsizing of the focusing lens unit can be realized, and fluctuation of chromatic aberration and fluctuation of curvature of field due to focusing can be corrected well.

The zoom lens is preferably capable of focusing from an infinite distance object to a near distance object by moving at least a part of lenses in the fourth lens group along the optical axis. For example, the zoom lens is preferably capable of focusing from an infinite distance object to a near distance object by moving at least two lenses in the fourth lens group along the optical axis.
With this configuration, downsizing of the focusing lens unit can be realized, and fluctuation of chromatic aberration and fluctuation of curvature of field due to focusing can be corrected well.

The zoom lens is preferably capable of focusing from an infinite distance object to a near distance object by moving a part or all of the fifth lens group along the optical axis.
According to this configuration, it is possible to satisfactorily correct the fluctuation of axial chromatic aberration, the fluctuation of spherical aberration, and the fluctuation of coma due to focusing.

Preferably, the zoom lens has an aperture stop between the second lens group and the third lens group.
By this configuration, spherical aberration, coma aberration, and lateral chromatic aberration can be corrected well.

  In addition, the optical apparatus includes the zoom lens having the above-described configuration. As a result, it is possible to realize an optical apparatus having a high F-number and high optical performance.

In the zoom lens manufacturing method, a first lens group having negative refractive power, a second lens group having positive refractive power, and a second lens group having negative refractive power are sequentially arranged from the object side along the optical axis. A method of manufacturing a zoom lens having a third lens group, a fourth lens group having positive refractive power, and a fifth lens group, wherein the fifth lens group has a meniscus shape with a convex surface facing the image side. It is configured to have a positive lens, and is configured to satisfy the following conditional expression, and at least a part of the lenses from the first lens group to the fifth lens group is a component in the direction orthogonal to the optical axis And the distance between the first lens group and the second lens group changes, and the distance between the second lens group and the third lens group changes. The distance between the third lens group and the fourth lens group changes, and Wherein the fourth lens group spacing between the fifth lens group are those configured to vary. In one example, the fifth lens group can have positive refractive power.
(1) 1.100 <(r1 + r2) / (r1-r2) <5.000
However,
r1: radius of curvature of the object-side surface of the positive lens r2: radius of curvature of the image-side surface of the positive lens

  Such a zoom lens manufacturing method makes it possible to manufacture a zoom lens lens having a bright F number and high optical performance.

(Numerical example)
Hereinafter, a zoom lens according to a numerical example will be described based on the attached drawings.

(First embodiment)
FIGS. 1A, 1B, and 1C are cross-sectional views of the zoom lens according to the first embodiment at the wide-angle end, at an intermediate focal length, and at the telephoto end, respectively.
Arrows under the respective lens units in FIG. 1A indicate the moving directions of the respective lens units during zooming from the wide-angle end state to the intermediate focal length state. Arrows under the respective lens units in FIG. 1B indicate moving directions of the respective lens units during zooming from the intermediate focal length state to the telephoto end state.

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

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

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

  The third lens group G3 includes, in order from the object side along the optical axis, an aperture stop S, a cemented lens of a biconcave lens L31 and a positive meniscus lens L32 with a convex surface facing the object side, and a flare cut stop FS It is done. The positive meniscus lens L32 is an aspheric lens having an aspheric lens surface on the image side.

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

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

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

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

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

  In the zoom lens according to the present embodiment, focusing from an infinite distance object to a near distance object is performed by moving the second F lens group G2F to the image plane I side.

  In the zoom lens according to the present embodiment, a component in a direction orthogonal to the optical axis with the cemented lens of the biconcave lens L31 of the third lens group G3 and the positive meniscus lens L32 having a convex surface facing the object side as a vibration reduction lens group. Image plane correction at the time of occurrence of image blur, that is, image stabilization is performed by moving in a direction including.

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

Table 1 below presents values of zoom lens according to the first example.
In [Overall specifications] in Table 1, f is the focal length of the whole zoom lens system, FNO is the f-number, ω is the half angle of view (unit: degree), Y is the image height, TL is the total optical system length, BF is The back focus is shown respectively. Here, the total length TL of the optical system is the distance on the optical axis from the lens surface closest to the object in the first lens group G1 to the image plane I. The back focus BF is a distance on the optical axis from the lens surface closest to the image in the fifth lens group G5 to the image plane I. Also, W indicates a wide-angle end state, M indicates an intermediate focal length state, and T indicates a focal length state at the telephoto end.

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

  [Lens group data] indicates the starting surface number and focal length of each lens group.

[Spherical surface data] shows the aspheric surface coefficient and the conical constant when the shape of the aspheric surface shown in [Surface data] is expressed by the following equation.
x = (h2 / r) / [1+ {1-κ (h / r) 2} 1/2]
+ A 4 h 4 + A 6 h 6 + A 8 h 8 + A 10 h 10
Here, h is the height in the direction perpendicular to the optical axis, x is the distance along the optical axis direction from the tangent plane of the apex of the aspheric surface at height h to the aspheric surface (sag amount), and κ is the conical constant , A4, A6, A8 and A10 are aspheric coefficients, and r is a radius of curvature (paraxial radius of curvature) of the reference spherical surface. Moreover, "E-n" shows "x10-n", for example, "1.234E-05" shows "1.234x10-5." The second-order aspheric coefficient A2 is 0, and the description is omitted.

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

  In addition, the code | symbol of Table 1 described above shall be similarly used also in the table | surface of each Example mentioned later.

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

[Plane data]
Face number r d nd d d
Object ∞
* 1) 75.44949 2.000 1.85135 40.1
* 2) 20.28508 6.283
3) 51.106676 2.000 1.90043 37.4
4) 24.72875 14.151
5) -37.47670 2.000 1.49782 82.6
6) 256.37590 0.150
7) 92.17324 6.061 2.00100 29.1
8) -101.88567 (variable)

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

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

18) (F-stop) 4.0 4.000
19) -191.55206 1.500 1.74400 44.8
20) 29.63471 3.611 1.80244 25.6
* 21) 65.28008 1.000
22) (FS) ∞ (variable)

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

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

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

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

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

Plane number: 9
κ = 1.00000E + 00
A4 = -2.87523E-06
A6 = 2.47805E-10
A8 = 0.00000 E + 00
A10 = 0.00000 E + 00

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

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

Plane number: 29
κ = 1.00000E + 00
A4 = 1.04301E-05
A6 =-2.89394E-08
A8 = 6.51407 E-11
A10 = -6.88449E-14

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

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

[Each conditional expression corresponding value]
(1) (r1 + r2) / (r1-r2) = 2.009
(2) | m12 |
(3) f5 / f4 = 0.891

2 (a), 2 (b) and 2 (c) show the zoom lens according to the first embodiment at the time of focusing on an infinity object in the wide-angle end state, the intermediate focal length state and the telephoto end state, respectively. FIG.
3 (a), 3 (b), and 3 (c) show the zoom lens according to the first embodiment at the time of near-field object focusing in the wide-angle end state, the intermediate focal length state, and the telephoto end state, respectively. FIG.
4 (a), 4 (b) and 4 (c) respectively show the meridional horizontal at the time of image stabilization in the wide-angle end state, the intermediate focal length state and the telephoto end state of the zoom lens according to the first embodiment. FIG.

  In each of the aberration diagrams, FNO denotes an F number, A denotes a light beam incident angle, that is, a half angle of view (unit: "°"), NA denotes a numerical aperture, and H0 denotes an object height (unit: mm). In the figure, d indicates the aberration curve at the d line (wavelength λ = 587.6 nm), g indicates the aberration curve at the g line (wavelength λ = 435.8 nm), and those not described indicate the d line An aberration curve is shown. The spherical aberration diagram shows the value of the F number corresponding to the maximum aperture, the astigmatism diagram and the distortion diagram show the maximum value of the half angle of view or the object height respectively, and in the lateral aberration diagram each half angle of view or each object height Indicates the value of. In astigmatism diagrams, a solid line indicates a sagittal image plane, and a broken line indicates a meridional image plane. Also, the lateral aberration diagrams show meridional lateral aberration with respect to the d-line and the g-line. The same reference numerals as in this example are used also in the various aberration diagrams of the examples below.

  As apparent from the respective aberration diagrams, in the zoom lens according to the first example, various aberrations are well corrected from the wide-angle end state to the telephoto end state, and also have high optical performance even at the time of vibration reduction. I understand.

Second Embodiment
FIGS. 5A, 5B, and 5C are cross-sectional views of the zoom lens according to the second embodiment at the wide-angle end, at the intermediate focal length, and at the telephoto end, respectively.
Arrows under the respective lens units in FIG. 5A indicate the moving directions of the respective lens units during zooming from the wide-angle end state to the intermediate focal length state. Arrows under the respective lens units in FIG. 5B indicate moving directions of the respective lens units during zooming from the intermediate focal length state to the telephoto end state.

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

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

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

  The third lens group G3 includes, in order from the object side along the optical axis, an aperture stop S, a cemented lens of a biconcave lens L31 and a positive meniscus lens L32 with a convex surface facing the object side, and a flare cut stop FS It is done. The positive meniscus lens L32 is an aspheric lens having an aspheric lens surface on the image side.

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

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

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

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

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

  In the zoom lens according to the present embodiment, focusing from an infinite distance object to a near distance object is performed by moving the second F lens group G2F to the image plane I side.

  In the zoom lens according to the present embodiment, a component in a direction orthogonal to the optical axis with the cemented lens of the biconcave lens L31 of the third lens group G3 and the positive meniscus lens L32 having a convex surface facing the object side as a vibration reduction lens group. Image plane correction at the time of occurrence of image blur, that is, image stabilization is performed by moving in a direction including.

Here, when the focal length of the entire zoom lens system according to the present embodiment is f, and the ratio of the amount of movement of the image on the image plane I to the amount of movement of the vibration reduction lens group at the time of blur correction is K In order to correct the rotational shake of θ, the anti-vibration lens group may be shifted by (f · tan θ) / K in the direction orthogonal to the optical axis.
In the zoom lens according to the present embodiment, in the wide-angle end state, the vibration reduction coefficient K is 0.56, and the focal length is 16.48 (mm) (see Table 2 below). The amount of movement of the anti-vibration lens group for correcting rotational shake is 0.42 (mm). Also, in the intermediate focal length state, the vibration reduction coefficient K is 0.70 and the focal length is 25.21 (mm) (see Table 2 below). The amount of movement of the anti-vibration lens group is 0.41 (mm). In the telephoto end state, the vibration reduction coefficient K is 0.87, and the focal length is 33.95 (mm) (see Table 2 below). The moving amount of the anti-vibration lens group is 0.38 (mm).

  Table 2 below presents values of zoom lens according to the second embodiment.

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

[Plane data]
Face number r d nd d d
Object ∞
* 1) 73.22991 2.000 1.85135 40.1
* 2) 19.62926 7.474
3) 61.15202 2.000 1.90043 37.4
4) 26.50584 12.785
5) -37.55896 2.000 1.49782 82.6
6) 312.93830 0.150
7) 97.61558 6.381 2.00100 29.1
8) -90.94529 (variable)

* 9) 45.22754 8.894 1.58313 59.4
10) -33.86178 1.500 1.65160 58.6
11) -73.70296 1.496
12) 108.06528 1.500 1.51742 52.2
13) 36.32590 (variable)

14) 27.56863 1.500 1.84416 24.0
15) 20.91099 12.393 1.48749 70.3
16) -40.68643 1.500 1.80328 25.5
17) -63.71042 (variable)

18) (F-stop) 3. 3.500
19) -208.49060 1.500 1.74400 44.8
20) 26.99 771 3.953 1.80244 25.6
* 21) 62.64116 1.000
22) (FS) ∞ (variable)

23) 26.91271 7.631 1.49782 82.6
24) -57.70103 1.500 1.88202 37.2
* 25) -93.99278 0.150
26) 62.42449 1.500 1.90043 37.4
27) 19.07512 7.749 1.49782 82.6
28) 83.05930 (variable)

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

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

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

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

Plane number: 9
κ = 1.00000E + 00
A4 = -2.97350E-06
A6 = -1.01164E-09
A8 = 5.03482E-12
A10 = -6.96957E-15

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

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

Plane number: 29
κ = 1.00000E + 00
A4 = 1.07645E-05
A6 = -4.55699E-08
A8 = 1.31690E-10
A10 = 1.37085E-13

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

[Variable interval data]
W M T W M T
Infinity infinity infinity infinity near distance near distance near distance
d 0 ∞ ∞ 0.01 110.01 115.53 110.00
β − − − − 0.1220 −0.1816 −0.2566
f 16.48 25.21 33.95---
d 8 28.899 9.423 0.500 33.772 14.498 6.164
d13 6.862 6.862 6.862 1.989 1.787 1.198
d17 2.000 5.572 7.582 2.000 5.572 7.582
d22 7.082 3.510 1.500 7.082 3.510 1.500
d28 4.315 18.275 32.723 4.315 18.275 32.723
BF 18.070 18.065 18.063 18.155 18.254 18.438

[Each conditional expression corresponding value]
(1) (r1 + r2) / (r1-r2) = 1.975
(2) | m12 | /fw=1.723
(3) f5 / f4 = 0.895

6 (a), 6 (b), and 6 (c) show the zoom lens according to the second embodiment at the time of focusing on an infinite object in the wide-angle end state, the intermediate focal length state, and the telephoto end state, respectively. FIG.
FIGS. 7A, 7B, and 7C show the zoom lens according to the second embodiment at the time of near distance object focusing in the wide-angle end state, the intermediate focal length state, and the telephoto end state, respectively. FIG.
8 (a), 8 (b), and 8 (c) show the meridional horizontal at the time of image stabilization in the wide-angle end state, the intermediate focal length state, and the telephoto end state of the zoom lens according to the second embodiment, respectively. FIG.

  As is apparent from the respective aberration diagrams, in the zoom lens according to the second example, various aberrations are well corrected from the wide-angle end state to the telephoto end state, and also have high optical performance even at the time of image stabilization. I understand.

Third Embodiment
FIGS. 9A, 9B, and 9C are cross-sectional views of the zoom lens according to the third embodiment in the wide-angle end state, in the intermediate focal length state, and in the telephoto end state, respectively.
Arrows under the respective lens units in FIG. 9A indicate the moving directions of the respective lens units during zooming from the wide-angle end state to the intermediate focal length state. Arrows under the respective lens units in FIG. 9B indicate moving directions of the respective lens units during zooming from the intermediate focal length state to the telephoto end state.

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

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

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

  The third lens group G3 includes, in order from the object side along the optical axis, an aperture stop S, a cemented lens of a biconcave lens L31 and a positive meniscus lens L32 with a convex surface facing the object side, and a flare cut stop FS It is done. The positive meniscus lens L32 is an aspheric lens having an aspheric lens surface on the image side.

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

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

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

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

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

  In the zoom lens according to the present embodiment, focusing from an infinite distance object to a near distance object is performed by moving the second F lens group G2F to the image plane I side.

  In the zoom lens according to the present embodiment, a component in a direction orthogonal to the optical axis with the cemented lens of the biconcave lens L31 of the third lens group G3 and the positive meniscus lens L32 having a convex surface facing the object side as a vibration reduction lens group. Image plane correction at the time of occurrence of image blur, that is, image stabilization is performed by moving in a direction including.

Here, when the focal length of the entire zoom lens system according to the present embodiment is f, and the ratio of the amount of movement of the image on the image plane I to the amount of movement of the vibration reduction lens group at the time of blur correction is K In order to correct the rotational shake of θ, the anti-vibration lens group may be shifted by (f · tan θ) / K in the direction orthogonal to the optical axis.
The zoom lens according to the present embodiment has an image stabilization coefficient K of 0.56 and a focal length of 16.48 (mm) (see Table 3 below) in the wide-angle end state, so 0.81 ° The amount of movement of the anti-vibration lens group for correcting rotational shake is 0.42 (mm). Moreover, in the intermediate focal length state, the vibration reduction coefficient K is 0.70 and the focal length is 25.21 (mm) (see Table 3 below). The amount of movement of the anti-vibration lens group is 0.41 (mm). In the telephoto end state, the vibration reduction coefficient K is 0.87, and the focal length is 33.95 (mm) (see Table 3 below). The moving amount of the vibration reduction lens group is 0.39 (mm).

  Table 3 below presents values of zoom lens according to the third example.

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

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

* 9) 45.12179 9.169 1.58313 59.4
10) -32.35918 1.500 1.65160 58.6
11) -70.95534 1.426
12) 116.36340 1.500 1.51742 52.2
13) 36.40999 (variable)

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

18) (F-stop) 3. 3.500
19) -209.12746 1.500 1.74400 44.8
20) 27.47317 3.887 1.80244 25.6
* 21) 62.77212 1.000
22) (FS) ∞ (variable)

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

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

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

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

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

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

Plane number: 21
κ = 1.36390E + 00
A4 = -1.54769E-07
A6 =-2.66171 E-08
A8 = 2.07963E-10
A10 = -5.54299E-13

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

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

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

[Variable interval data]
W M T W M T
Infinity infinity infinity infinity near distance near distance near distance
d 0 ∞ ∞ 0.00 110.00 115.79 110.00
β − − − − 0.1221 −0.1814 −0.2567
f 16.48 25.21 33.95---
d 8 28.797 9.141 0.500 33.624 14.169 6.113
d13 6.847 6.847 6.847 2.020 1.820 1.234
d17 2.000 5.812 7.792 2.000 5.812 7.792
d22 7.292 3.480 1.500 7.292 3.480 1.500
d28 4.346 17.791 32.643 4.346 17.791 32.643
BF 18.069 18.479 18.059 18.154 18.667 18.434

[Each conditional expression corresponding value]
(1) (r1 + r2) / (r1-r2) = 1.976
(2) | m12 | /fw=1.717
(3) f5 / f4 = 0.889

10 (a), 10 (b), and 10 (c) show the zoom lens according to the third embodiment at the time of focusing on an infinity object in the wide-angle end state, the intermediate focal length state, and the telephoto end state, respectively. FIG.
11 (a), 11 (b) and 11 (c) show the zoom lens according to the third embodiment at the time of near-field focusing in the wide-angle end state, the intermediate focal length state and the telephoto end state, respectively. FIG.
12 (a), 12 (b) and 12 (c) show the meridional horizontal at the time of image stabilization in the wide-angle end state, the intermediate focal length state and the telephoto end state of the zoom lens according to the third embodiment, respectively. FIG.

  As is apparent from the respective aberration diagrams, in the zoom lens according to the third example, various aberrations are well corrected from the wide-angle end state to the telephoto end state, and also have high optical performance even at the time of vibration reduction. I understand.

Fourth Embodiment
FIGS. 13A, 13B, and 13C are cross-sectional views of the zoom lens according to the fourth example at the wide-angle end, at an intermediate focal length, and at the telephoto end, respectively.
Arrows under the respective lens units in FIG. 13A indicate moving directions of the respective lens units during zooming from the wide-angle end state to the intermediate focal length state. Arrows under the respective lens units in FIG. 13B indicate moving directions of the respective lens units during zooming from the intermediate focal length state to the telephoto end state.

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

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

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

  The third lens group G3 includes, in order from the object side along the optical axis, an aperture stop S, a cemented lens of a biconcave lens L31 and a positive meniscus lens L32 with a convex surface facing the object side, and a flare cut stop FS It is done. The positive meniscus lens L32 is an aspheric lens having an aspheric lens surface on the image side.

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

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

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

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

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

  In the zoom lens according to the present embodiment, focusing from an infinite distance object to a near distance object is performed by moving the second F lens group G2F to the image plane I side.

  In the zoom lens according to the present embodiment, a component in a direction orthogonal to the optical axis with the cemented lens of the biconcave lens L31 of the third lens group G3 and the positive meniscus lens L32 having a convex surface facing the object side as a vibration reduction lens group. Image plane correction at the time of occurrence of image blur, that is, image stabilization is performed by moving in a direction including.

Here, when the focal length of the entire zoom lens system according to the present embodiment is f, and the ratio of the amount of movement of the image on the image plane I to the amount of movement of the vibration reduction lens group at the time of blur correction is K In order to correct the rotational shake of θ, the anti-vibration lens group may be shifted by (f · tan θ) / K in the direction orthogonal to the optical axis.
In the zoom lens according to this example, the vibration reduction coefficient K is 0.81 and the focal length is 18.54 (mm) (see Table 4 below) in the wide-angle end state, so 0.77 ° The amount of movement of the anti-vibration lens group for correcting rotational shake is 0.30 (mm). Also, in the intermediate focal length state, the vibration reduction coefficient K is 1.00 and the focal length is 25.21 (mm) (see Table 4 below). The amount of movement of the anti-vibration lens group is 0.29 (mm). In the telephoto end state, the vibration reduction coefficient K is 1.26, and the focal length is 33.95 (mm) (see Table 4 below). The moving amount of the anti-vibration lens group is 0.27 (mm).

  Table 4 below presents values of zoom lens according to the fourth example.

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

[Plane data]
Face number r d nd d d
Object ∞
* 1) 64.13853 2.000 1.82080 42.7
* 2) 20.52237 7.450
3) 42.79628 2.000 1.84300 37.4
4) 23.01367 14.005
5) -42.12649 2.000 1.49782 82.6
6) 60.80104 0.150
7) 55.48158 6.486 2.00100 29.1
8) -197.93506 (variable)

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

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

18) (F-stop) 4.0 4.000
19) -144.55027 1.500 1.74400 44.8
20) 20.23731 4.012 1.80244 25.6
* 21) 40.54944 1.000
22) (FS) ∞ (variable)

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

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

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

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

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

Plane number: 9
κ = 1.00000E + 00
A4 = -3.25645E-06
A6 = 5.35394E-10
A8 = 0.00000 E + 00
A10 = 0.00000 E + 00

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

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

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

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

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

[Each conditional expression corresponding value]
(1) (r1 + r2) / (r1-r2) = 2.234
(2) | m12 |
(3) f5 / f4 = 1.915

FIGS. 14 (a), 14 (b) and 14 (c) show the zoom lens according to the fourth embodiment at the time of focusing on an infinity object in the wide-angle end state, the intermediate focal length state and the telephoto end state, respectively. FIG.
FIGS. 15 (a), 15 (b) and 15 (c) show the zoom lens according to the fourth embodiment at the time of near object focusing in the wide-angle end state, the intermediate focal length state and the telephoto end state, respectively. FIG.
16 (a), 16 (b) and 16 (c) show the meridional horizontal at the time of image stabilization in the wide-angle end state, the intermediate focal length state and the telephoto end state of the zoom lens according to the fourth embodiment, respectively. FIG.

  As apparent from the respective aberration diagrams, in the zoom lens according to the fourth example, various aberrations are well corrected from the wide-angle end state to the telephoto end state, and also has high optical performance even at the time of vibration reduction. I understand.

Fifth Embodiment
FIGS. 17A, 17B, and 17C are cross-sectional views of the zoom lens according to the fifth embodiment at the wide-angle end, at the intermediate focal length, and at the telephoto end, respectively.
Arrows under the respective lens units in FIG. 17A indicate the moving directions of the respective lens units during zooming from the wide-angle end state to the intermediate focal length state. Arrows under the respective lens units in FIG. 17B indicate moving directions of the respective lens units upon zooming from the intermediate focal length state to the telephoto end state.

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

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

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

  The third lens group G3 includes, in order from the object side along the optical axis, an aperture stop S, a cemented lens of a biconcave lens L31 and a positive meniscus lens L32 with a convex surface facing the object side, and a flare cut stop FS It is done. The positive meniscus lens L32 is an aspheric lens having an aspheric lens surface on the image side.

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

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

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

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

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

  In the zoom lens according to the present embodiment, focusing from an infinite distance object to a near distance object is performed by moving the second F lens group G2F to the image plane I side.

  In the zoom lens according to the present embodiment, a component in a direction orthogonal to the optical axis with the cemented lens of the biconcave lens L31 of the third lens group G3 and the positive meniscus lens L32 having a convex surface facing the object side as a vibration reduction lens group. Image plane correction at the time of occurrence of image blur, that is, image stabilization is performed by moving in a direction including.

Here, when the focal length of the entire zoom lens system according to the present embodiment is f, and the ratio of the amount of movement of the image on the image plane I to the amount of movement of the vibration reduction lens group at the time of blur correction is K In order to correct the rotational shake of θ, the anti-vibration lens group may be shifted by (f · tan θ) / K in the direction orthogonal to the optical axis.
The zoom lens according to the present embodiment has an image stabilization coefficient K of 0.47 and a focal length of 15.45 (mm) (see Table 5 below) in the wide-angle end state, so 0.84 ° The amount of movement of the anti-vibration lens group for correcting rotational shake is 0.48 (mm). Also, in the intermediate focal length state, the vibration reduction coefficient K is 0.61 and the focal length is 25.21 (mm) (see Table 5 below). The amount of movement of the anti-vibration lens group is 0.48 (mm). In the telephoto end state, the vibration reduction coefficient K is 0.76, and the focal length is 33.95 (mm) (see Table 5 below). The moving amount of the anti-vibration lens group is 0.44 (mm).

  Table 5 below presents values of zoom lens according to the fifth example.

(Table 5) Fifth Example [Overall Specifications]
W M T
f 15.45 25.21 33.95
FNO 2.83 2.83 2.83
ω 56.2 40.0 31.8
Y 21.64 21.64 21.64
TL 168.787 161.395 167.660
BF 18.061 18.070 18.058

[Plane data]
Face number r d nd d d
Object ∞
* 1) 84.32721 2.000 1.82080 42.7
* 2) 22.42250 6.533
3) 40.43903 2.000 1.90043 37.4
4) 22.7989. 18.443
5) -36.72174 2.000 1.49782 82.6
6) 108. 66132 0.150
7) 86.07473 6.091 2.00100 29.1
8) -113.52466 (variable)

* 9) 56.20536 8.334 1.58313 59.4
10) -34.822724 1.500 1.62896 51.8
11) -62.67282 0.150
12) 15221 1690 1.500 1.51742 52.2
13) 63.48881 (variable)

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

18) (F-stop) 4.0 4.000
19) -402.90754 1.500 1.74400 44.8
20) 29.51707 4.016 1.80244 25.6
* 21) 67.51202 1.000
22) (FS) ∞ (variable)

23) 30.01453 8.025 1.49782 82.6
24) -48.32228 1.500 1.88202 37.2
* 25) -80.74589 0.150
26) 73.99805 1.500 1.90043 37.4
27) 19.28578 8.491 1.49782 82.6
28) 131.61654 (variable)

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

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

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

Plane number: 2
κ = 2.82500E-01
A4 = -2.25879E-06
A6 = 2.9379E-09
A8 = -1.07006E-13
A10 = 2.38338E-15

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

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

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

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

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

[Variable interval data]
W M T W M T
Infinity infinity infinity infinity near distance near distance near distance
d 0 ∞ ∞ 10 103.58 110.97 104.70
β----0.1177 -0.1847 -0.2625
f 15.45 25.21 33.95---
d 8 32.660 9.394 0.500 37.602 14.284 5.903
d13 6.126 6.126 6.126 1.184 1.237 0.724
d17 1.500 5.658 7.190 1.500 5.658 7.190
d22 7.190 3.032 1.500 7.190 3.032 1.500
d28 3.889 19.760 34.930 3.889 19.760 34.930
BF 18.061 18.070 18.058 18.146 18.265 18.451

[Each conditional expression corresponding value]
(1) (r1 + r2) / (r1-r2) = 2.030
(2) | m12 | / fw = 2.082
(3) f5 / f4 = 0.775

18 (a), 18 (b) and 18 (c) show the zoom lens according to the fifth embodiment at the time of focusing on an infinity object in the wide-angle end state, the intermediate focal length state and the telephoto end state, respectively. FIG.
19 (a), 19 (b), and 19 (c) show the zoom lens according to the fifth embodiment at the time of near-field object focusing in the wide-angle end state, the intermediate focal length state, and the telephoto end state, respectively. FIG.
20 (a), 20 (b), and 20 (c) show the meridional horizontal at the time of image stabilization in the wide-angle end state, the intermediate focal length state, and the telephoto end state of the zoom lens according to the fifth example, respectively. FIG.

  As apparent from the respective aberration diagrams, in the zoom lens according to the fifth example, various aberrations are well corrected from the wide-angle end state to the telephoto end state, and also has high optical performance even at the time of image stabilization. I understand.

Sixth Embodiment
FIGS. 21 (a), 21 (b) and 21 (c) are cross-sectional views of the zoom lens according to the sixth embodiment at the wide-angle end, at the intermediate focal length, and at the telephoto end, respectively.
Arrows under the respective lens units in FIG. 21A indicate moving directions of the respective lens units upon zooming from the wide-angle end state to the intermediate focal length state. Arrows under the respective lens units in FIG. 21B indicate the moving directions of the respective lens units during zooming from the intermediate focal length state to the telephoto end state.

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

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

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

  The third lens group G3 includes, in order from the object side along the optical axis, an aperture stop S, a cemented lens of a biconcave lens L31 and a positive meniscus lens L32 with a convex surface facing the object side, and a flare cut stop FS It is done.

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

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

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

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

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

  In the zoom lens according to the present embodiment, focusing from an infinite distance object to a near distance object is performed by moving the second F lens group G2F to the image plane I side.

  Further, in the zoom lens according to the present embodiment, image plane correction at the time of occurrence of an image blur, that is, image stabilization by moving the second R lens group G2R as a vibration reduction lens group in a direction including a component in a direction orthogonal It is carried out.

Here, when the focal length of the entire zoom lens system according to the present embodiment is f, and the ratio of the amount of movement of the image on the image plane I to the amount of movement of the vibration reduction lens group at the time of blur correction is K In order to correct the rotational shake of θ, the anti-vibration lens group may be shifted by (f · tan θ) / K in the direction orthogonal to the optical axis.
The zoom lens according to this example has an image stabilization coefficient K of 1.07 and a focal length of 16.48 (mm) (see Table 6 below) in the wide-angle end state, so 0.81 ° The moving amount of the anti-vibration lens group for correcting rotational shake is 0.22 (mm). In the intermediate focal length state, the vibration reduction coefficient K is 1.37 and the focal length is 25.21 (mm) (see Table 6 below). The amount of movement of the anti-vibration lens group is 0.21 (mm). In the telephoto end state, the vibration reduction coefficient K is 1.67, and the focal length is 33.95 (mm) (see Table 6 below). The moving amount of the anti-vibration lens group is 0.20 (mm).

  Table 6 below provides data values of the zoom lens according to the sixth example.

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

[Plane data]
Face number r d nd d d
Object ∞
* 1) 180.13769 2.000 1.82080 42.7
* 2) 19.96088 6.970
3) 94.52854 2.000 1.90043 37.4
* 4) 28.44278 9.857
5) -42.62350 2.000 1.49782 82.6
6) 244.0 8326 0.150
7) 61.25466 5.605 2.00100 29.1
8) -150.06559 (variable)

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

* 14) 43.25649 1.500 1.79504 28.7
15) 26.23 995 11.085 1.48 749 70.3
16) -21.42752 1.500 1.68893 31.2
17)-29.56586 (variable)

18) (F-stop) 4.0 4.000
19) -74.75529 1.500 1.74400 44.8
20) 22.57348 3.362 1.80244 25.6
21) 84.92681 1.000
22) (FS) ∞ (variable)

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

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

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

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

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

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

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

Plane number: 14
κ = 1.00000E + 00
A4 = -4. 10738E-06
A6 = 2.26991 E-09
A8 = -1.27958E-11
A10 = 2.28497E-14

Plane number: 25
κ = 1.00000E + 00
A4 = 6.63910E-06
A6 =-2.70332 E-09
A8 = -1.14938E-11
A10 = -3. 8980 E-14

Plane number: 29
κ = 1.00000E + 00
A4 = 2.96724E-06
A6 = -7.34747 E-10
A8 = 4.28602E-11
A10 = -7.07831E-14

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

[Variable interval data]
W M T W M T
Infinity infinity infinity infinity near distance near distance near distance
d 0 ∞ ∞ ∞ 110.00 115.69 111.40
β − − − − 0.1243 −0.1848 −0.2589
f 16.48 25.21 33.95---
d 8 27.344 8.875 0.500 31.204 12.826 4.873
d13 7.541 7.541 7.511 3.681 3.590 3.168
d17 2.000 7.319 11.342 2.000 7.319 11.342
d22 10.842 5.524 1.500 10.842 5.524 1.500
d28 4.704 17.488 30.153 4.704 17.488 30.158
BF 18.069 18.064 18.074 18.157 18.259 18.456

[Each conditional expression corresponding value]
(1) (r1 + r2) / (r1-r2) = 2.052
(2) | m12 | / fw = 1.629
(3) f5 / f4 = 1.036

22 (a), 22 (b), and 22 (c) show the zoom lens according to the sixth embodiment at the time of focusing on an infinity object in the wide-angle end state, the intermediate focal length state, and the telephoto end state, respectively. FIG.
FIGS. 23 (a), 23 (b) and 23 (c) show the zoom lens according to the sixth embodiment at the time of near object focusing in the wide-angle end state, the intermediate focal length state and the telephoto end state, respectively. FIG.
FIGS. 24 (a), 24 (b) and 24 (c) show the meridional horizontal at the time of image stabilization in the wide-angle end state, the intermediate focal length state and the telephoto end state of the zoom lens according to the sixth embodiment, respectively. FIG.

  As is apparent from the aberration diagrams, in the zoom lens according to Example 6, various aberrations are corrected well from the wide-angle end state to the telephoto end state, and also has high optical performance even at the time of vibration reduction. I understand.

Seventh Embodiment
FIGS. 25 (a), 25 (b) and 25 (c) are cross-sectional views of the zoom lens according to the seventh embodiment at the wide-angle end, at the intermediate focal length, and at the telephoto end, respectively.
Arrows under the respective lens units in FIG. 25A indicate the moving directions of the respective lens units during zooming from the wide-angle end state to the intermediate focal length state. Arrows under the respective lens units in FIG. 25B indicate the moving directions of the respective lens units during zooming from the intermediate focal length state to the telephoto end state.

  As shown in FIG. 25A, the zoom lens according to the present embodiment includes, in order from the object side along the optical axis, a first lens group G1 having negative refractive power, and a second lens group having positive refractive power. It comprises a lens group G2, a third lens group G3 having negative refractive power, a fourth lens group G4 having positive refractive power, and a fifth lens group G5 having positive refractive power.

  The first lens group G1 includes, in order from the object side along the optical axis, a negative meniscus lens L11 having a convex surface facing the object, a negative meniscus lens L12 having a convex surface facing the object, and a concave surface facing the object It comprises a negative meniscus lens L13 and a biconvex lens L14. The negative meniscus lens L11 is an aspheric lens in which the lens surface on the object side and the lens surface on the image side are aspheric.

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

  The third lens group G3 includes, in order from the object side along the optical axis, an aperture stop S, a cemented lens of a biconcave lens L31 and a positive meniscus lens L32 with a convex surface facing the object side, and a flare cut stop FS It is done. The positive meniscus lens L32 is an aspheric lens having an aspheric lens surface on the image side.

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

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

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

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

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

  In the zoom lens according to the present embodiment, focusing from an infinite distance object to a near distance object is performed by moving the second F lens group G2F to the image plane I side.

  In the zoom lens according to the present embodiment, a component in a direction orthogonal to the optical axis with the cemented lens of the biconcave lens L31 of the third lens group G3 and the positive meniscus lens L32 having a convex surface facing the object side as a vibration reduction lens group. Image plane correction at the time of occurrence of image blur, that is, image stabilization is performed by moving in a direction including.

Here, when the focal length of the entire zoom lens system according to the present embodiment is f, and the ratio of the amount of movement of the image on the image plane I to the amount of movement of the vibration reduction lens group at the time of blur correction is K In order to correct the rotational shake of θ, the anti-vibration lens group may be shifted by (f · tan θ) / K in the direction orthogonal to the optical axis.
The zoom lens according to the present embodiment has an image stabilization coefficient K of 0.56 and a focal length of 16.48 (mm) (see Table 7 below) in the wide-angle end state, so 0.81 ° The amount of movement of the anti-vibration lens group for correcting rotational shake is 0.42 (mm). Moreover, in the intermediate focal length state, the vibration reduction coefficient K is 0.70 and the focal length is 25.21 (mm) (see Table 7 below). The amount of movement of the anti-vibration lens group is 0.41 (mm). In the telephoto end state, the vibration reduction coefficient K is 0.87, and the focal length is 33.95 (mm) (see Table 7 below). The moving amount of the vibration reduction lens group is 0.39 (mm).

  Table 7 below presents values of zoom lens according to the seventh example.

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

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

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

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

18) (F-stop) 4.0 4.000
19) -172.99604 1.500 1.74400 44.8
20) 25.25276 3.145 1.80244 25.6
* 21) 65.
22) (FS) ∞ (variable)

23) 28.13736 7.94 1.49782 82.6
24) -39.84408 1.500 1.88202 37.2
* 25)-55. 75469 0.150
26) 79.86144 1.500 1.90043 37.4
27) 18.03173 8.303 1.49782 82.6
28) 109.39627 (variable)

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

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

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

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

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

Plane number: 21
κ = 1.89270E + 00
A4 = -3. 35320E-07
A6 = -5.17749E-08
A8 = 8.91765E-10
A10 = -5.73216E-12

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

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

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

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

[Each conditional expression corresponding value]
(1) (r1 + r2) / (r1-r2) = 1.963
(2) | m12 | / fw = 1.593
(3) f5 / f4 = 0.843

26 (a), 26 (b), and 26 (c) show the zoom lens according to the seventh embodiment at the time of focusing on an infinity object in the wide-angle end state, the intermediate focal length state, and the telephoto end state, respectively. FIG.
27 (a), 27 (b) and 27 (c) show the zoom lens according to the seventh embodiment at the time of near distance object focusing in the wide-angle end state, the intermediate focal length state and the telephoto end state, respectively. FIG.
28 (a), 28 (b) and 28 (c) show the meridional horizontal at the time of image stabilization in the wide-angle end state, the intermediate focal length state and the telephoto end state of the zoom lens according to the seventh embodiment, respectively. FIG.

  As apparent from the respective aberration diagrams, in the zoom lens according to the seventh example, various aberrations are corrected well from the wide-angle end state to the telephoto end state, and also has high optical performance even at the time of vibration reduction. I understand.

Eighth embodiment
FIGS. 29A, 29B, and 29C are cross-sectional views of the zoom lens according to the eighth embodiment in the wide-angle end state, in the intermediate focal length state, and in the telephoto end state, respectively.
Arrows under the respective lens units in FIG. 29A indicate the moving directions of the respective lens units during zooming from the wide-angle end state to the intermediate focal length state. Arrows under the respective lens units in FIG. 29B indicate moving directions of the respective lens units during zooming from the intermediate focal length state to the telephoto end state.

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

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

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

  The third lens group G3 includes, in order from the object side along the optical axis, an aperture stop S, a cemented lens of a biconcave lens L31 and a positive meniscus lens L32 with a convex surface facing the object side, and a flare cut stop FS It is done.

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

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

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

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

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

  In the zoom lens according to the present embodiment, focusing from an infinite distance object to a near distance object is performed by moving the second F lens group G2F to the image plane I side.

  In the zoom lens according to the present embodiment, a cemented lens of a double convex lens L41 in the fourth lens group G4 and a negative meniscus lens L42 having a concave surface facing the object side serves as a vibration reduction lens group in a direction orthogonal to the optical axis. Image plane correction at the time of occurrence of image blur, that is, image stabilization is performed by moving in the direction including the component.

Here, when the focal length of the entire zoom lens system according to the present embodiment is f, and the ratio of the amount of movement of the image on the image plane I to the amount of movement of the vibration reduction lens group at the time of blur correction is K In order to correct the rotational shake of θ, the anti-vibration lens group may be shifted by (f · tan θ) / K in the direction orthogonal to the optical axis.
The zoom lens according to the present example has an image stabilization coefficient K of 0.84 and a focal length of 16.48 (mm) (see Table 8 below) in the wide-angle end state, so 0.81 ° The amount of movement of the anti-vibration lens group for correcting rotational shake is 0.28 (mm). In the intermediate focal length state, the vibration reduction coefficient K is 1.12, and the focal length is 25.21 (mm) (see Table 8 below). The amount of movement of the anti-vibration lens group is 0.26 (mm). In the telephoto end state, the vibration reduction coefficient K is 1.39, and the focal length is 33.94 (mm) (see Table 8 below), so as to correct rotational shake of 0.57 °. The moving amount of the anti-vibration lens group is 0.24 (mm).

  Table 8 below provides data values of the zoom lens according to the eighth example.

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

[Plane data]
Face number r d nd d d
Object ∞
* 1) 193.58721 2.000 1.8080 42.7
* 2) 20.02145 6.905
3) 90.01817 2.000 1.90043 37.4
* 4) 27.89307 9.933
5) -41.38646 2.000 1.49782 82.6
6) 388.04959 0.150
7) 63.78120 5.582 2.00100 29.1
8) -140.47475 (variable)

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

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

18) (F-stop) 4.0 4.000
19) -117.95737 1.500 1.74400 44.8
20) 20.54277 3.285 1.80244 25.6
21) 54.89929 1.000
22) (FS) ∞ (variable)

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

* 29) -135.00000 4.710 1.77250 49.5
* 30) -48.921153 (BF)
Image plane ∞

[Lens group data]
Front focal length
G1-23.31
G2 9 35.87
G3 18-54.84
G4 23 83.18
G5 29 97.01

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

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

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

Plane number: 9
κ = 1.00000E + 00
A4 = -5.99537E-06
A6 = -8.64207E-09
A8 = 0.00000 E + 00
A10 = 0.00000 E + 00

Plane number: 14
κ = 1.00000E + 00
A4 = -5.24252E-06
A6 = 3.78138E-09
A8 = -1.26184E-11
A10 = -1.01048E-14

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

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

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

[Variable interval data]
W M T W M T
Infinity infinity infinity infinity near distance near distance near distance
d 0 ∞ ∞ ∞ 116.21 121.52 117.46
β----0.1183 -0.1768 -0.2470
f 16.48 25.21 33.94---
d 8 27.092 8.876 0.500 30.852 12.622 4.589
d13 7.348 7.348 7.348 3.588 3.603 3.259
d17 2.000 6.293 9.740 2.000 6.293 9.740
d22 9.240 4.94 1.500 9.240 4.94 1.500
d28 4.528 17.433 29.874 4.528 17.433 29.874
BF 18.066 18.053 18.060 18.146 18.232 18.406

[Each conditional expression corresponding value]
(1) (r1 + r2) / (r1-r2) = 2.137
(2) | m12 | /fw=1.614
(3) f5 / f4 = 1.166

30 (a), 30 (b), and 30 (c) show the zoom lens according to the eighth embodiment at the time of focusing on an infinity object in the wide-angle end state, the intermediate focal length state, and the telephoto end state, respectively. FIG.
31 (a), 31 (b), and 31 (c) show the zoom lens according to the eighth embodiment at the time of near-field object focusing in the wide-angle end state, the intermediate focal length state, and the telephoto end state, respectively. FIG.
32 (a), 32 (b) and 32 (c) show the meridional horizontal at the time of image stabilization in the wide-angle end state, the intermediate focal length state and the telephoto end state of the zoom lens according to the eighth example, respectively. FIG.

  As apparent from the respective aberration diagrams, in the zoom lens according to the eighth example, various aberrations are corrected well from the wide-angle end state to the telephoto end state, and also has high optical performance even at the time of image stabilization. I understand.

(9th embodiment)
FIGS. 33A, 33B, and 33C are cross-sectional views of the zoom lens according to the ninth embodiment in the wide-angle end state, in the intermediate focal length state, and in the telephoto end state, respectively.
Arrows under the respective lens units in FIG. 33A indicate moving directions of the respective lens units upon zooming from the wide-angle end state to the intermediate focal length state. Arrows under the respective lens units in FIG. 33B indicate the moving directions of the respective lens units during zooming from the intermediate focal length state to the telephoto end state.

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

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

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

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

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

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

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

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

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

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

  The zoom lens according to the present embodiment is a cemented lens of a negative meniscus lens L24 having a convex surface facing the object side in the second lens group G2, a biconvex lens L25, and a negative meniscus lens L26 having a concave surface facing the object side. Image plane correction at the time of occurrence of image blur, that is, image stabilization is performed by moving in a direction including a component in a direction orthogonal to the optical axis as a vibration reduction lens group.

Here, when the focal length of the entire zoom lens system according to the present embodiment is f, and the ratio of the amount of movement of the image on the image plane I to the amount of movement of the vibration reduction lens group at the time of blur correction is K In order to correct the rotational shake of θ, the anti-vibration lens group may be shifted by (f · tan θ) / K in the direction orthogonal to the optical axis.
The zoom lens according to this example has an image stabilization coefficient K of 1.06 and a focal length of 16.48 (mm) (see Table 9 below) in the wide-angle end state, so 0.81 ° The moving amount of the anti-vibration lens group for correcting rotational shake is 0.22 (mm). In the intermediate focal length state, the vibration reduction coefficient K is 1.32, and the focal length is 25.21 (mm) (see Table 9 below). The amount of movement of the anti-vibration lens group is 0.22 (mm). Also, in the telephoto end state, the vibration reduction coefficient K is 1.64 and the focal length is 33.95 (mm) (see Table 9 below), so as to correct rotational shake of 0.57 °. The moving amount of the anti-vibration lens group is 0.20 (mm).

  Table 9 below provides values of zoom lens according to the ninth example.

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

[Plane data]
Face number r d nd d d
Object ∞
* 1) 206.62948 2.000 1.8 2080 42.7
* 2) 22.78595 5.394
3) 79.60930 2.000 1.90043 37.4
* 4) 28.62293 12.227
5)-36.79633 2.000 1.49782 82.6
6) 138.93269 0.150
7) 59.13309 5.614 2.00100 29.1
8) -157.09491 (variable)

* 9) 78.52593 8.740 1.58313 59.4
10) -18.33622 1.500 1.65844 50.8
11)-31. 62205 0.320
12) -53.95141 1.500 1.51742 52.2
13) 1642.72200 5.830
* 14) 56. 55132 1. 500 1. 79 504 28.7
15) 30.04155 10.867 1.48749 70.3
16) -20.18962 1.500 1.68893 31.2
17) -26.35355 (variable)

18) (F-stop) ((Variable)

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

22) 43.71137 7.983 1.49782 82.6
23) -23.27350 1.500 1.88202 37.2
* 24)-31.21137 0.150
25) 71.81959 1.500 1.90043 37.4
26) 18.76437 8.473 1.49782 82.6
27) 145.88740 (variable)

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

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

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

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

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

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

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

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

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

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

[Variable interval data]
W M T W M T
Infinity infinity infinity infinity near distance near distance near distance
d 0 ∞ ∞ ∞ 110.00 117.87 110.60
β----0.1310 -0.194 -0.2863
f 16.48 25.21 33.95---
d 8 27.288 7.805 0.500 27.288 7.805 0.500
d17 2.000 7.042 8.304 2.000 7.042 8.304
d18 4.000 4.000 4.000 5.664 7.386 9.288
d21 12.429 7.386 6.125 10.765 4.000 0.837
d27 2.468 15.455 34.496 2.468 15.455 34.496
BF 23.901 22.523 18.063 23.999 22.740 18.534

[Each conditional expression corresponding value]
(1) (r1 + r2) / (r1-r2) = 2.259
(2) | m12 | /fw=1.626
(3) f5 / f4 = 1.278

34 (a), 34 (b) and 34 (c) show the zoom lens according to the ninth embodiment at the time of focusing on an infinity object in the wide-angle end state, the intermediate focal length state and the telephoto end state, respectively. FIG.
35 (a), 35 (b) and 35 (c) show the zoom lens according to the ninth embodiment at the time of near object focusing in the wide-angle end state, the intermediate focal length state and the telephoto end state, respectively. FIG.
36 (a), 36 (b) and 36 (c) show the meridional horizontal at the time of image stabilization in the wide-angle end state, the intermediate focal length state and the telephoto end state of the zoom lens according to the ninth embodiment, respectively. FIG.

  As apparent from the respective aberration diagrams, in the zoom lens according to the ninth example, various aberrations are corrected well from the wide-angle end state to the telephoto end state, and also has high optical performance even at the time of vibration reduction. I understand.

Tenth Example
FIGS. 37A, 37B, and 37C are cross-sectional views of the zoom lens according to Example 10 at the wide-angle end, at the intermediate focal length, and at the telephoto end, respectively.
Arrows under the respective lens units in FIG. 37A indicate the moving directions of the respective lens units during zooming from the wide-angle end state to the intermediate focal length state. Arrows under the respective lens units in FIG. 37B indicate the moving directions of the respective lens units during zooming from the intermediate focal length state to the telephoto end state.

  As shown in FIG. 37A, the zoom lens according to the present embodiment includes, in order from the object side along the optical axis, a first lens unit G1 having a negative refractive power, and a second lens unit having a positive refractive power. It comprises a lens group G2, a third lens group G3 having negative refractive power, a fourth lens group G4 having positive refractive power, and a fifth lens group G5 having positive refractive power.

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

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

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

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

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

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

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

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

  In the zoom lens according to the present embodiment, focusing from an infinite distance object to a near distance object is performed by moving the fourth F lens group G4F to the object side.

  The zoom lens according to the present embodiment is a cemented lens of a negative meniscus lens L24 having a convex surface facing the object side in the second lens group G2, a biconvex lens L25, and a negative meniscus lens L26 having a concave surface facing the object side. Image plane correction at the time of occurrence of image blur, that is, image stabilization is performed by moving in a direction including a component in a direction orthogonal to the optical axis as a vibration reduction lens group.

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

  Table 10 below provides data values of the zoom lens according to the tenth example.

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

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

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

18) (F-stop) 4.0 4.000
19) -95.69123 1.500 1.74400 44.8
20) 28.24642 3.135 1.80244 25.6
21) 114.16154 (variable)

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

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

* 28) -135.00000 4.98 1.77250 49.5
* 29) -46.24500 (BF)
Image plane ∞

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

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

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

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

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

Plane number: 14
κ = 1.00000E + 00
A4 = -3.99540E-06
A6 = 6.900128 E-09
A8 = -7.15162E-11
A10 = 2.30252E-13

Plane number: 24
κ = 1.00000E + 00
A4 = 2.95224E-06
A6 = 6.33151 E-09
A8 = -6.95778E-11
A10 = 9.58472 E-14

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

Plane number: 29
κ = 1.00000E + 00
A4 = 7.09095E-06
A6 = -3.5 3806E-09
A8 = 1.19967E-11
A10 = -2.88780 E-14

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

[Each conditional expression corresponding value]
(1) (r1 + r2) / (r1-r2) = 2.042
(2) | m12 | / fw = 1.593
(3) f5 / f4 = 0.586

38 (a), 38 (b) and 38 (c) show the zoom lens according to Example 10 when focusing on an infinity object in the wide-angle end state, in the intermediate focal length state and in the telephoto end state, respectively. FIG.
39 (a), 39 (b), and 39 (c) show the zoom lens according to Example 10 when focusing on a short distance at the wide-angle end, at the intermediate focal length, and at the telephoto end, respectively. FIG.
40 (a), 40 (b) and 40 (c) show the meridional horizontal at the time of image stabilization in the wide-angle end state, the intermediate focal length state and the telephoto end state of the zoom lens according to the tenth embodiment, respectively. FIG.

  As is apparent from the respective aberration diagrams, in the zoom lens according to Example 10, various aberrations are corrected well from the wide-angle end state to the telephoto end state, and also has high optical performance even at the time of image stabilization. I understand.

(Eleventh embodiment)
41 (a), 41 (b), and 41 (c) are cross-sectional views of the zoom lens according to Example 11 at the wide-angle end, at the intermediate focal length, and at the telephoto end, respectively.
Arrows under the respective lens units in FIG. 41A indicate the moving directions of the respective lens units at the time of zooming from the wide-angle end state to the intermediate focal length state. Arrows under the respective lens units in FIG. 41B indicate moving directions of the respective lens units during zooming from the intermediate focal length state to the telephoto end state.

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

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

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

  The third lens group G3 includes, in order from the object side along the optical axis, an aperture stop S, a cemented lens of a biconcave lens L31 and a positive meniscus lens L32 with a convex surface facing the object side, and a flare cut stop FS It is done.

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

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

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

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

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

  Further, in the zoom lens according to the present embodiment, focusing from an infinite distance object to a close distance object is performed by moving the fifth lens group G5 to the object side.

  The zoom lens according to the present embodiment is a cemented lens of a negative meniscus lens L24 having a convex surface facing the object side in the second lens group G2, a biconvex lens L25, and a negative meniscus lens L26 having a concave surface facing the object side. Image plane correction at the time of occurrence of image blur, that is, image stabilization is performed by moving in a direction including a component in a direction orthogonal to the optical axis as a vibration reduction lens group.

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

  Table 11 below provides data values of the zoom lens according to the eleventh example.

(Table 11) 11th embodiment [overall specifications]
W M T
f 16.48 25.21 33.94
FNO 4.00 4.00 4.00
ω 54.1 40.4 32.8
Y 21.64 21.64 21.64
TL 162.327 153.706 157.417
BF 18.026 19.051 18.015

[Plane data]
Face number r d nd d d
Object ∞
* 1) 132.59820 2.000 1.8080 42.7
* 2) 19.32271 7.442
3) 160.87743 2.000 1.90043 37.4
* 4) 32.91214 9.741
5) -38.07464 2.000 1.49782 82.6
6) 561.24096 0.150
7) 73.09225 5.033 2.00100 29.1
8) -129.44599 (variable)

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

18) (F-stop) 4.0 4.000
19) -105.52859 1.500 1.74400 44.8
20) 25.92479 2.859 1.80244 25.6
21) 69.72964 1.000
22) (FS) ∞ (variable)

23) 65.71858 10859 1.49782 82.6
24) -19.28535 1.500 1.88202 37.2
* 25)-31.97958 0.150
26) 89.977758 1.500 1.90043 37.4
27) 24.75006 11.838 1.49782 82.6
28) -103.72759 (variable)

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

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

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

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

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

Plane number: 9
κ = 1.00000E + 00
A4 = -2.85903E-06
A6 = -6.88788E-09
A8 = 0.00000 E + 00
A10 = 0.00000 E + 00

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

Plane number: 25
κ = 1.00000E + 00
A4 = 4.32494E-06
A6 = 5.82097E-09
A8 = -4.56687E-11
A10 = 3.78592 E-14

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

Plane number: 30
κ = 1.00000E + 00
A4 = 8.93441E-06
A6 = -2.66479E-08
A8 = 2.35900E-11
A10 = -9.65459E-15

[Variable interval data]
W M T W M T
Infinity infinity infinity infinity near distance near distance near distance
d 0 ∞ ∞ 0.00 230.00 238.63 234.90
β − − − − 0.0651 −0.0951 −0.1271
f 16.48 25.21 33.94---
d 8 29.064 8.952 0.500 29.064 8.952 0.500
d17 2.000 9.68 15.25 2.000 9.68 15.225
d22 14.725 7.042 1.500 14.725 7.042 1.500
d28 4.371 14.839 28.037 0.147 6.667 14.415
BF 18.026 19.051 18.012 22.275 22.275 31.731

[Each conditional expression corresponding value]
(1) (r1 + r2) / (r1-r2) = 2.596
(2) | m12 | /fw=1.734
(3) f5 / f4 = 1.835

42 (a), 42 (b) and 42 (c) show the zoom lens according to Example 11 when focusing on an infinity object in the wide-angle end state, in the intermediate focal length state and in the telephoto end state, respectively. FIG.
43 (a), 43 (b) and 43 (c) show the zoom lens according to Example 11 when focusing on a near object in the wide-angle end state, in the intermediate focal length state and in the telephoto end state, respectively. FIG.
44 (a), 44 (b) and 44 (c) respectively show the meridional horizontal at the time of image stabilization in the wide-angle end state, the intermediate focal length state and the telephoto end state of the zoom lens according to Example 11. FIG.

  As is apparent from the respective aberration diagrams, in the zoom lens according to Example 11, various aberrations are favorably corrected from the wide-angle end state to the telephoto end state, and also has high optical performance even at the time of vibration reduction. I understand.

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

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

  In addition, said each Example shows one specific example, and embodiment is not limited to these. The following contents can be adopted appropriately as long as the optical performance of the zoom lens is not impaired.

  Although a zoom lens having a five-group configuration is shown as a numerical example of the zoom lens, it is also applicable to other group configurations such as, for example, a six-group. Also, the lens or lens group may be added to the most object side, or the lens or lens group may be added to the most image side. The lens group indicates a portion having at least one lens separated by an air gap.

  In the zoom lens, a single or a plurality of lens groups or a partial lens group may be moved in the optical axis direction to provide a focusing lens group for focusing from an infinite distance object to a near distance object. The focusing lens group can also be applied to autofocus, and is also suitable for driving by a motor for autofocus, such as an ultrasonic motor. In particular, although it is preferable that a part of the second lens group G2 be a focusing lens group, it is preferable that the whole or a part of the third lens group G3 and the fifth lens group G5 be a focusing lens group. The entire second lens group G2 may be used as a focusing lens group.

  Also, in the zoom lens, the lens group or the partial lens group is moved so as to have a component perpendicular to the optical axis, or is rotationally moved (rocked) in a direction including the optical axis to correct image blurring caused by camera shake It is good also as an anti-vibration lens group. In particular, although it is preferable that the whole third lens group G3 be a vibration reduction lens group, the whole or a part of the fourth lens group G4 may be a vibration reduction lens group, and a part of the third lens group G4. As a vibration reduction lens group.

  Further, the lens surface of the lens constituting the zoom lens may be spherical or flat, or aspheric. When the lens surface is spherical or flat, it is preferable because lens processing and assembly adjustment can be facilitated, and deterioration of optical performance due to lens processing and assembly adjustment errors can be prevented. In addition, even when the image plane shifts, it is preferable because the deterioration of the imaging performance is small. When the lens surface is aspheric, any of aspheric aspheric surfaces by grinding, a glass mold aspheric surface formed by shaping a glass into aspheric surface shape, or a composite aspheric surface formed by forming a resin on a glass surface into an aspheric surface shape Good. The lens surface may be a diffractive surface, and the lens may be a gradient index lens (GRIN lens) or a plastic lens.

  Further, in the zoom lens, it is preferable that the aperture stop be disposed between the second lens group G2 and the third lens group G3, but the role of the aperture stop is not limited to providing a member as the aperture stop. May be substituted.

  In addition, an anti-reflection film having high transmittance over a wide wavelength range may be provided on the lens surface of the lens constituting the zoom lens in order to reduce flare and ghost and to achieve high optical performance with high contrast. .

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

  When the photographer presses a release button (not shown), the quick return mirror 3 retracts out of the optical path, and the light of an object (subject) condensed by the photographing lens 2 forms an object image on the image sensor 11. Thereby, the light from the object is imaged by the imaging device 11 and stored as an object image in a memory (not shown). Thus, the photographer can shoot an object with the camera 1.

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

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

The zoom lens manufacturing method includes, in order from the object side along the optical axis, a first lens group having negative refractive power, a second lens group having positive refractive power, and a third lens having negative refractive power. 46. A method of manufacturing a zoom lens having a lens group, a fourth lens group having a positive refractive power, and a fifth lens group having a positive refractive power, and as shown in FIG. S4 is included.
Step S1: The fifth lens group is configured to have a positive meniscus lens with a convex surface facing the image side.
Step S2: The following conditional expression (1) is satisfied.
(1) 1.100 <(r1 + r2) / (r1-r2) <5.000
However,
r1: radius of curvature of the object-side surface of the positive lens r2: radius of curvature of the image-side surface of the positive lens Step S3: a part of the lenses from the first lens group to the fifth lens group is an optical axis Movably to include a component in a direction orthogonal to
Step S4: During zooming from the wide-angle end state to the telephoto end state, the distance between the first lens group and the second lens group changes, and the distance between the second lens group and the third lens group is The distance between the third lens group and the fourth lens group changes, and the distance between the fourth lens group and the fifth lens group changes.

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

G1 1st lens group G2 2nd lens group G3 3rd lens group G4 4th lens group Gf 5th lens group Gf focusing lens group S aperture stop FS flare cut stop I image surface 1 optical device 2 photographing lens 3 quick return mirror 5 Focusing Plate 7 Penta Prism 9 Eyepiece 11 Image Sensor

Claims (1)

From the object side along the optical axis, a first lens group having negative refractive power, a second lens group having positive refractive power, a third lens group having negative refractive power, and positive refractive power And a fifth lens group, and
At the time of zooming, the distance between the first lens group and the second lens group changes, and the distance between the second lens group and the third lens group changes, and the third lens group and the fourth lens group change. The distance between the lens group changes, and the distance between the fourth lens group and the fifth lens group changes
At least a part of the lenses from the first lens group to the fifth lens group is configured to be movable so as to include a component in a direction orthogonal to the optical axis,
The fifth lens group has a positive meniscus lens with a convex surface facing the image side,
A zoom lens that satisfies the following conditional expressions.
1.100 <(r1 + r2) / (r1-r2) <5.000
However,
r1: radius of curvature of the object-side surface of the positive lens r2: radius of curvature of the image-side surface of the positive lens

Images