ZOOM LENS AND IMAGE DEVICE

Abstract

Zoom lens (1) comprising as a whole four or five lens groups, which, starting from one side of the object, consist of a first lens group (G1) having a positive refractive power and fixed relative to an image plane (Sim) during a change in magnification, a second lens group (G2) having a negative refractive power and moving during the change in magnification, one or two intermediate lens groups (G3, G4) comprising an mp lens group (G3 or G4) having a positive refractive power and moving during the change in magnification, and a rearmost lens group (G4 or G5) located at the image-side position of the entire system, having a positive refractive power and fixed relative to the image plane (Sim) during the change in magnification, the change in magnification is achieved by changing all distances between the adjacent lens groups, the most posterior lens group (G4 or G5), in order starting from the object side, consists of an anterior group (L41 to L44 or L51 to L54) with a positive refractive power, a middle group (Ois) with a negative refractive power and a posterior group (L48 to L51 or L58 to L61) with a positive refractive power, The air gaps between the front group and the middle group, and between the middle group and the rear group, remain constant during magnification changes and focusing. the anterior group includes at least two positive lenses and at least one negative lens, Image stabilization is achieved by shifting only the center group in directions perpendicular to the direction of the optical axis (Z). wherein the back group comprises a cemented lens (L49, L50 or L59, L60) formed by a positive lens and a negative lens cemented together, and the following conditional expressions (1) and (2) are satisfied: 0.20 < FGr3 / FGr < 0.45 1.75 < FGr1 / FGr3 < 3.00 where FGr3 is a focal length of the rear group of the furthest rear lens group, FGr is a focal length of the furthest rear lens group, and FGr1 is a focal length of the front group of the furthest rear lens group.

Description

BACKGROUND OF THE INVENTION Area of ​​the invention

[0001] The present invention relates to a zoom lens suitable for use with, in particular, digital cameras, interchangeable-lens digital cameras, etc., and to an imaging device equipped with the zoom lens. Description of the state of the art

[0002] So-called constant aperture zoom lenses with a zoom ratio of approximately 2.5 to 3.0 and a constant maximum aperture of approximately F2.8 or F4 over the entire zoom range are known.

[0003] Such a zoom lens has a four-group or five-group configuration, comprising, for example, in order starting from the object side, a first lens group which has a positive refractive power and is fixed during a change in magnification, a second lens group which has a negative refractive power and has a strong magnification change effect, approximately one or two magnification change groups which are provided in addition to the second lens group and which include a lens group with a positive refractive power, and a rearmost lens group which is fixed during a change in magnification.

[0004] In recent years, many lenses for digital cameras, single-lens reflex cameras, mirrorless cameras, etc., have been equipped with an image stabilization mechanism, and zoom lenses of the type described above, equipped with an image stabilization mechanism, are known as taught in patent documents 1 to 3. [Previous state documents][Patent documents] [Patent Document 1] Japanese Unexamined Patent Publication JP 2011- 99 964 A [Patent document 2] Japanese unexamined patent publication JP 2011-158599A [Patent document 3] Japanese unexamined patent publication JP 2012-118097A

[0005] Furthermore, a zoom lens of the type described above is also known from publication US 8,659,832 B2. SUMMARY OF THE INVENTION

[0006] In cases where an image stabilization function is provided, it is important to reduce the load exerted on the drive system by reducing the size and weight of the image stabilization lens unit and the displacement range of the image stabilization lens group. To address this problem, the most image-side lens group, as described in each of patent documents 1 to 3, consists of a front group with a positive refractive power, a middle group with a negative refractive power, and a rear group with a positive refractive power, with the middle group with a negative refractive power being used as the image stabilization lens group.

[0007] By arranging the lens group with a positive refractive power in front of the image stabilization lens group in this manner, the height of a ray incident on the image stabilization lens group is reduced, thus achieving a reduction in the size of the image stabilization lens group. Furthermore, by giving the image stabilization group a refractive power with the opposite sign to that of the lens groups in front of and behind it, the refractive power of the image stabilization lens group can be increased, thereby enhancing the sensitivity of the image shift to a shift in the image stabilization lens group.

[0008] As described above, it is desirable to reduce the size and weight of the image stabilization lens group and to reduce its displacement range. Furthermore, it is desirable to suppress variations in chromatic aberration and decentering coma caused by displacement of the image stabilization lens group. Providing the image stabilization lens group with a high refractive power increases its sensitivity, thus allowing for a reduction in the lens's displacement range. However, in this case, suppressing decentering coma becomes more difficult, and the sensitivity to mounting errors is also increased. Therefore, optimizing the refractive power of the image stabilization lens group is crucial.It is also important to optimize the configuration of the lens groups in front of and behind the image stabilization lens group, which affect the refractive power (sensitivity) of the image stabilization lens group and variation of aberrations when the lens is moved.

[0009] Most conventional lenses with the specifications described above are designed as interchangeable lenses for single-lens reflex cameras, and few such lenses are optimized for use as interchangeable lenses for so-called mirrorless cameras. The zoom lenses taught in patent documents 1 to 3 are optimized for use as interchangeable lenses for single-lens reflex cameras. In the case of an interchangeable lens for mirrorless cameras, it is not necessary to provide a back focus as long as that of an interchangeable lens for single-lens reflex cameras, and the optimal configuration of the rearmost lens group is naturally different from the conventional configuration.

[0010] In patent document 1, the front group of the rearmost lens group consists of only two positive lenses. To reduce the height of the beam incident on the image stabilization lens group, to provide the image stabilization lens group with a strong refractive power, and to reduce the overall length of the lens, it is necessary to provide the front group of the rearmost lens group with a strong refractive power. In this case, however, it is difficult to suppress spherical aberration, coma, and chromatic aberration. If, on the other hand, the front group is provided with a weak refractive power to avoid the situation described above, it is difficult to ensure sufficient refractive power for the image stabilization lens group, and the refractive power of the entire rearmost lens group becomes weak, resulting in a longer overall length of the optical system.The zoom lens of patent document 2 also exhibits the problems described above.

[0011] In patent documents 2 and 3, the image stabilization lens group does not exhibit strong refractive power, and its sensitivity is not high. In this case, the displacement range of the image stabilization lens during image stabilization becomes large, or a strong image stabilization effect is not expected.

[0012] In view of the circumstances described above, the present invention is directed to provide a zoom lens with high optical performance, high sensitivity to an image stabilization lens group, and suppressed variation of aberrations during image stabilization, as well as an imaging device equipped with the zoom lens.

[0013] A first aspect of the zoom lens according to the invention consists of four or five lens groups as a whole, which, starting from the object side, comprise a first lens group having a positive refractive power and remaining fixed relative to the image plane during a change in magnification, a second lens group having a negative refractive power and moving during the change in magnification, (exactly) one or two intermediate lens groups comprising an mp lens group having a positive refractive power and moving during the change in magnification, and a rearmost lens group located at the image-side position of the entire system, having a positive refractive power and remaining fixed relative to the image plane during the change in magnification. the change in magnification is achieved by changing all distances between the adjacent lens groups, The most posterior lens group, in order starting from the object side, consists of an anterior group with a positive refractive power, a medial group with a negative refractive power and a posterior group with a positive refractive power. The air gaps between the front group and the middle group, and between the middle group and the rear group, remain constant during magnification changes and focusing. the anterior group includes at least two positive lenses and at least (exactly) one negative lens, Image stabilization is achieved by shifting only the center group in directions perpendicular to the direction of the optical axis, and the following conditional expressions (1) and (2) are satisfied: 0.20 <FGr3 / FGr<0,45 and 1.75 <FGr1 / FGr3<3,00 where FGr3 is a focal length of the rear group of the furthest rear lens group, FGr is a focal length of the furthest rear lens group, and FGr1 is a focal length of the front group of the furthest rear lens group.

[0014] A second aspect of the zoom lens according to the invention consists of four or five lens groups as a whole, which, starting from the object side, comprise a first lens group having a positive refractive power and remaining fixed relative to the image plane during a change in magnification, a second lens group having a negative refractive power and moving during the change in magnification, (exactly) one or two intermediate lens groups comprising an mp lens group having a positive refractive power and moving during the change in magnification, and a rearmost lens group located at the image-side position of the entire system, having a positive refractive power and remaining fixed relative to the image plane during the change in magnification. the change in magnification is achieved by changing all distances between the adjacent lens groups, The most posterior lens group, in order starting from the object side, consists of an anterior group with a positive refractive power, a medial group with a negative refractive power and a posterior group with a positive refractive power. The air gaps between the front group and the middle group, and between the middle group and the rear group, remain constant during magnification changes and focusing. the anterior group includes at least two positive lenses, Image stabilization is achieved by shifting only the center group in directions perpendicular to the direction of the optical axis. the rear group includes a negative lens at its most image-side position, and the following conditional expressions (1) and (2) are satisfied: 0.20 <FGr3 / FGr<0,45 and 1.75 <FGr1 / FGr3<3,00 where FGr3 is a focal length of the rear group of the furthest rear lens group, FGr is a focal length of the furthest rear lens group, and FGr1 is a focal length of the front group of the furthest rear lens group.

[0015] It should be noted that the mp lens group is not part of a lens group (a sub-lens group) and is (precisely) an independent lens group. Here, "independent lens group" refers to a lens group in which the distance between the lens group and the adjacent lens group changes during a change in magnification. In the case that the middle lens group consists of two lens groups, and both of the two lens groups have a positive refractive power, the mp lens group can be either of the two lens groups.

[0016] In the zoom lens according to the invention, it is preferred that the rear group comprises a single lens with a negative meniscus shape at its furthest image-side position, the concave surface of which is directed towards the object side.

[0017] The Rück group is designed to include a cemented lens formed by (exactly) one positive lens and (exactly) one negative lens cemented together.

[0018] It is preferred that the anterior group consists of three positive lenses and (exactly) one negative lens.

[0019] It is preferred that the middle group consists of two negative lenses and (exactly) one positive lens.

[0020] It is preferred that the lens surface furthest towards the object of the back group is a convex surface and that the back group comprises a negative lens arranged at its image-side position and a cemented lens arranged on the object side of the negative lens.

[0021] In this case, it is preferred that the back group, starting from the object side, consists of a positive single lens, a cemented lens formed by (exactly) one positive lens and (exactly) one negative lens cemented together, and a single lens with a negative meniscus shape whose concave surface is directed towards the object side.

[0022] It is preferred that the first lens group, starting from the object side, consists of a negative lens, a positive lens, a positive lens and a positive lens.

[0023] It is preferred that focusing from an object at infinity to a next object is effected by moving only the entire mp lens group or a part of the lenses forming the mp lens group along the optical axis (Z).

[0024] It is preferred that the following condition expression (3) is satisfied: 0.5 <FGr1 / FGr<1,3 where FGr1 is a focal length of the front group of the furthest rear lens group and FGr is a focal length of the furthest rear lens group.

[0025] It is preferred that the following condition expression (4) is satisfied: 0.25 <FGr1 / Ft<0,60 where FGr1 is a focal length of the front group of the furthest rear lens group and Ft is a focal length of the entire system when the zoom lens at the telephoto end is focused on an object at infinity.

[0026] It is preferred that the following condition expression (5) is satisfied: 0.12 <FGr3 / Ft<0,27 where FGr3 is a focal length of the rear group of the rearmost lens group and Ft is a focal length of the entire system when the zoom lens at the telephoto end is focused on an object at infinity.

[0027] It is preferred that the following condition expression (6) is satisfied: 0.12 <BF / Ft<0,28 where BF is an equivalent air distance from the furthest rear lens group to the image plane and Ft is a focal length of the entire system when the zoom lens at the telephoto end is focused on an object at infinity.

[0028] It is preferred that the following condition expression (7) is satisfied: 1.1 <TL / Ft<1,6 where TL is the total length of the optical system and Ft is the focal length of the entire system when the zoom lens is focused at the telephoto end on an object at infinity. It should be noted that the total length of the optical system here refers to the distance from the object-side surface of the zoom lens furthest from the object to the image plane, where the distance from the image-side surface of the zoom lens furthest from the image plane is an equivalent air gap.

[0029] It is preferred that the zoom lens consists of four lens groups, which, starting from the object side, comprise the first lens group, the second lens group, the mp lens group and the rearmost lens group.

[0030] An imaging device according to the invention comprises the zoom lens described above.

[0031] It should be noted that the expression "consisting of / comprising" as used here means that the zoom lens may include, in addition to the elements mentioned above: lenses that have essentially no refractive power; optical elements other than lenses, such as an aperture, a mask, a cover glass, and filters; and mechanical components such as a lens flange, a lens tube, an image sensor, an image stabilization mechanism, etc.

[0032] The sign (positive or negative) regarding the surface shape and refractive power of any lens that includes an aspheric surface refers to the paraxial (near-axis) region.

[0033] The first aspect of the zoom lens according to the invention consists of four or five lens groups as a whole, which, starting from the object side, comprise the first lens group, which has a positive refractive power and is fixed relative to the image plane during the magnification change; the second lens group, which has a negative refractive power and is moved during the magnification change; (exactly) one or two center lens groups comprising the mp lens group, which has a positive refractive power and is moved during the magnification change; and the rearmost lens group, which is arranged at the image-side position of the entire system, has a positive refractive power and is fixed relative to the image plane during the magnification change, wherein the magnification change is effected by changing all distances between the adjacent lens groups.the rearmost lens group, in order starting from the object side, consists of a front group with a positive refractive power, a middle group with a negative refractive power and a back group with a positive refractive power, air gaps between the front group and the middle group and between the middle group and the back group are constant during magnification changes and during focusing, the front group comprises at least two positive lenses and at least (exactly) one negative lens, image stabilization is achieved by shifting only the middle group in directions perpendicular to the direction of the optical axis, and the following condition expressions (1) and (2) are satisfied: 0.20 <FGr3 / FGr<0,45 and 1.75 <FGr1 / FGr3<3,00

[0034] This configuration allows the creation of a zoom lens with high optical performance, high sensitivity to the image stabilization lens group, and suppressed variation of aberrations during image stabilization.

[0035] The second aspect of the zoom lens according to the invention consists of four or five lens groups as a whole, which, starting from the object side, comprise a first lens group having a positive refractive power and remaining fixed relative to the image plane during the magnification change, a second lens group having a negative refractive power and moving during the magnification change, (exactly) one or two center lens groups comprising the mp lens group having a positive refractive power and moving during the magnification change, and the rearmost lens group, located at the image-side position of the entire system, having a positive refractive power and remaining fixed relative to the image plane during the magnification change, wherein the magnification change is effected by changing all distances between the adjacent lens groups.the rearmost lens group, in order starting from the object side, consists of a front group with a positive refractive power, a middle group with a negative refractive power, and a back group with a positive refractive power; air gaps between the front group and the middle group and between the middle group and the back group are constant during magnification changes and during focusing; the front group comprises at least two positive lenses; image stabilization is achieved by shifting only the middle group in directions perpendicular to the direction of the optical axis; the back group comprises a negative lens at its image-side position; and the following condition expressions (1) and (2) are satisfied: 0.20 <FGr3 / FGr<0,45 1.75 <FGr1 / FGr3<3,00

[0036] This configuration allows the creation of a zoom lens with high optical performance, high sensitivity to the image stabilization lens group, and suppressed variation of aberrations during image stabilization.

[0037] The imaging device according to the invention, which is equipped with the zoom lens according to the invention, can achieve a large image stabilization effect and allows the production of high-quality images. BRIEF DESCRIPTION OF THE DRAWINGS Fig. Figure 1 is a sectional view illustrating the lens configuration of a zoom lens according to an embodiment of the present invention (a zoom lens of Example 1). Fig. Figure 2 is a sectional view illustrating the lens configuration of a zoom lens from Example 2 of the invention. Fig.Figure 3 is a sectional view illustrating the lens configuration of a zoom lens from Example 3 of the invention. Fig. Figure 4 is a sectional view illustrating the lens configuration of a zoom lens from Example 4 of the invention. Fig. Figure 5 is a sectional view illustrating the lens configuration of a zoom lens from Example 5 of the invention. Fig. Figure 6 is a sectional view illustrating the lens configuration of a zoom lens from Example 6 of the invention. Fig. Figure 7 is a sectional view illustrating the lens configuration of a zoom lens from Example 7 of the invention. Fig. Figure 8 is a sectional view illustrating the lens configuration of a zoom lens from Example 8 of the invention. Fig. Figure 9 is a sectional view illustrating the lens configuration of a zoom lens from Example 9 of the invention. Fig.Figure 10 shows aberration diagrams of the zoom lens of Example 1 of the invention, Fig. Figure 11 shows aberration diagrams of the zoom lens of Example 2 of the invention, Fig. Figure 12 shows aberration diagrams of the zoom lens of Example 3 of the invention, Fig. Figure 13 shows aberration diagrams of the zoom lens from Example 4 of the invention. Fig. Figure 14 shows aberration diagrams of the zoom lens of Example 5 of the invention. Fig. Figure 15 shows aberration diagrams of the zoom lens from Example 6 of the invention. Fig. Figure 16 shows aberration diagrams of the zoom lens of Example 7 of the invention. Fig. Figure 17 shows aberration diagrams of the zoom lens of Example 8 of the invention, Fig. Figure 18 shows aberration diagrams of the zoom lens of Example 9 of the invention, Fig.Figure 19 shows lateral aberration diagrams of the zoom lens of Example 1 of the invention, Fig. Figure 20 shows lateral aberration diagrams of the zoom lens of Example 1 of the invention (with image stabilization), Fig. Figure 21 shows lateral aberration diagrams of the zoom lens of Example 2 of the invention. Fig. Figure 22 shows lateral aberration diagrams of the zoom lens of Example 2 of the invention (with image stabilization), Fig. Figure 23 shows lateral aberration diagrams of the zoom lens of Example 3 of the invention. Fig. Figure 24 shows lateral aberration diagrams of the zoom lens of Example 3 of the invention (with image stabilization), Fig. Figure 25 shows lateral aberration diagrams of the zoom lens of Example 4 of the invention. Fig. Figure 26 shows lateral aberration diagrams of the zoom lens of Example 4 of the invention (with image stabilization), Fig.Figure 27 shows lateral aberration diagrams of the zoom lens of Example 5 of the invention. Fig. Figure 28 shows lateral aberration diagrams of the zoom lens of Example 5 of the invention (with image stabilization), Fig. Figure 29 shows lateral aberration diagrams of the zoom lens of Example 6 of the invention. Fig. Figure 30 shows lateral aberration diagrams of the zoom lens of Example 6 of the invention (with image stabilization), Fig. Figure 31 shows lateral aberration diagrams of the zoom lens of Example 7 of the invention. Fig. Figure 32 shows lateral aberration diagrams of the zoom lens of Example 7 of the invention (with image stabilization), Fig. Figure 33 shows lateral aberration diagrams of the zoom lens of Example 8 of the invention. Fig. Figure 34 shows lateral aberration diagrams of the zoom lens of Example 8 of the invention (with image stabilization), Fig.Figure 35 shows lateral aberration diagrams of the zoom lens of Example 9 of the invention. Fig. Figure 36 shows lateral aberration diagrams of the zoom lens of Example 9 of the invention (with image stabilization), Fig. Figure 37 is a perspective view showing the front of an imaging device according to an embodiment of the invention, and Fig. 38 is a perspective view showing the back of the building. Fig. 37 shows the imaging device. DESCRIPTION OF PREFERRED EXECUTION FORMS

[0038] An embodiment of the present invention is described in detail below with reference to the drawings. Fig. Figure 1 is a sectional view illustrating the lens configuration of a zoom lens according to one embodiment of the invention. The Fig.The illustrated configuration example is the same as the configuration of a zoom lens from Example 1, which is described later. Fig. 1 is the left side, the object side, and the right side is the image side. An aperture stop St shown in the drawing does not necessarily represent its size or shape, but rather its position along the optical axis Z. In the drawings, the symbol "Focus" denotes a focusing lens group used to achieve focusing, and the symbol "Ois" denotes an image stabilization lens group used to achieve image stabilization.

[0039] As in Fig.As shown in Figure 1, this zoom lens consists, in order starting from the object side, of a first lens group G1, which has a positive refractive power and is fixed relative to the image plane Sim during a change in magnification, a second lens group G2, which has a negative refractive power and is moved during the change in magnification, a third lens group G3 (which corresponds to an mp lens group according to the invention), which has a positive refractive power and is moved during the change in magnification, and a fourth lens group G4 (the rearmost lens group), which has a positive refractive power and is fixed relative to the image plane during the change in magnification, wherein the change in magnification is effected by changing all distances between the adjacent lens groups.

[0040] Locking the first lens group G1 and the fourth lens group G4 (the rearmost lens group) during magnification changes is advantageous for creating a so-called constant-aperture zoom lens. Locking the first lens group G1 also simplifies the use of a dustproof, weather-sealed structure.

[0041] When this zoom lens is used with an imaging device, it is preferable to provide a cover glass, a prism, and various filters, such as an infrared cutoff filter and a low-pass filter, etc., between the optical system and the imaging plane, depending on the configuration of the camera to which the lens is mounted. In the Fig. In the example shown in Figure 1, an optical element PP in the form of a plane-parallel plate, which is intended to represent such elements, is arranged between the lens system and the imaging plane Sim.

[0042] The fourth lens group G4 (the most posterior lens group) consists, in order starting from the object side, of an anterior group with a positive refractive power (lenses L41 to L44), a middle group with a negative refractive power (lenses L45 to L47; in Fig. 1 designated “Ois”) and a rear group with a positive refractive power (lenses L48 to L51), wherein the air gaps between the front group and the middle group and between the middle group and the rear group are constant during magnification changes and during focusing.

[0043] The front group comprises at least two positive lenses. Image stabilization is achieved by shifting only the middle group in directions perpendicular to the optical axis. The rear group comprises a negative lens at its position furthest from the image.

[0044] The front group, comprising at least two positive lenses, allows for successful correction of spherical aberration and coma, even if the front group and the middle group, which is the image stabilization lens group, have a high refractive power. If the front group, in addition to the at least two positive lenses, includes at least exactly one negative lens, successful correction of chromatic aberration can be achieved.

[0045] Furthermore, the negative lens positioned at the image-side position of the rear group allows the outgoing beam angle of the marginal ray to be increased by reducing the overall length of the lens. This configuration is particularly suitable for cases such as interchangeable lenses for so-called mirrorless cameras, where it is not necessary to provide a rear focus mechanism as long as that of an interchangeable lens for single-lens reflex cameras.

[0046] In the fourth lens group G4 (the rearmost lens group), the ray height through the front group, which has a positive refractive power, is reduced to achieve size and weight reduction of the middle group, which is the image stabilization lens group. The front and middle groups have refractive powers with opposite signs to allow the image stabilization group to have a strong refractive power, thus increasing the sensitivity of image shifts. This allows for a large image stabilization effect with a small shift range.

[0047] The zoom lens according to the invention satisfies the following condition expressions (1) and (2): 0.20 <FGrG / FGr<0,45 0.23 <FGr3 / FGr<0,45 1.75 <FGr1 / FGr3<3,00 1.80 <FGr1 / FGr3<2,80 where FGr3 is a focal length of the rear group of the furthest rear lens group, FGr is a focal length of the furthest rear lens group, and FGr1 is a focal length of the front group of the furthest rear lens group.

[0048] Condition expression (1) defines the ratio of the refractive power of the rear group in the fourth lens group G4 (the rearmost lens group). Meeting the lower limit of condition expression (1) prevents the refractive power of the rear group from becoming excessively strong, which is advantageous for correcting coma and distortion. Alternatively, meeting the lower limit of condition expression (1) simplifies obtaining the necessary back focus. Meeting the upper limit of condition expression (1) prevents the refractive power of the fourth lens group G4 (the rearmost lens group) from becoming excessively weak, which is advantageous for correcting astigmatism. Meeting the upper limit of condition expression (1) is also advantageous for reducing the overall length of the lens.

[0049] Condition expression (2) defines the ratio of the refractive power of the anterior group to the refractive power of the posterior group in the fourth lens group G4 (the most posterior lens group). Satisfying the lower limit of condition expression (2) prevents the refractive power of the anterior group from becoming excessively strong, which is advantageous for correcting spherical aberration and coma. Satisfying the upper limit of condition expression (2) prevents the refractive power of the posterior group from becoming excessively strong, which is advantageous for correcting coma and distortion. Alternatively, satisfying the upper limit of condition expression (2) prevents the refractive power of the anterior group from becoming excessively weak.This allows the incident ray height on the central group, which is the image stabilization lens group, to be kept low and the central group to be given a strong refractive power, which is advantageous for reducing the size of the image stabilization lens unit. That is, fulfilling condition (2) allows aberration correction and a size reduction of the image stabilization group to be achieved without increasing the size of the lens.

[0050] It should be noted that higher performance can be obtained if the conditional expressions (1-1) and / or (2-1) are satisfied.

[0051] In the zoom lens of this embodiment, it is preferred that the rear group, at its furthest image-side position, comprises a single lens with a negative meniscus shape, the concave surface of which faces the object side. The rear group, comprising a negative lens at its furthest image-side position, allows the output beam angle of the marginal ray to be increased, thereby reducing the overall length of the lens. This configuration is particularly suitable for applications such as interchangeable lenses for so-called mirrorless cameras, where it is not necessary to provide a rear focus mechanism as long as that of an interchangeable lens for single-lens reflex cameras. The negative meniscus shape with its object-side concave surface is advantageous for correcting field curvature and distortion.

[0052] It is preferred if the Rück group includes a cemented lens formed by exactly one positive lens and exactly one negative lens cemented together. The placement of the cemented lens in the Rück group allows for successful correction of lateral chromatic aberration.

[0053] It is preferred if the front group consists of three positive lenses and exactly one negative lens. This configuration allows for successful correction of spherical and chromatic aberration, even if the front group has a high refractive power, in order to reduce the incident ray height on the image stabilizing lens group and to reduce the overall length of the optical system.

[0054] It is preferred if the center group consists of two negative lenses and exactly one positive lens. This configuration allows for the suppression of aberration variations during image stabilization.

[0055] It is preferred that the most object-side lens surface in the rear group is convex, a negative lens is positioned at the most image-side position of the rear group, and a cemented lens is located on the object side of the negative lens. To increase the sensitivity of the center group, which is the image stabilization lens group, it is necessary to provide the center group with a strong negative refractive power. By reducing the angle of the marginal ray emanating from the center group with the most object-side convex surface of the rear group and by positioning the cemented lens closest to the convex surface, successful correction of aberrations, such as chromatic aberration, can be achieved. Furthermore, the negative lens at the most image-side position allows for an increase in the exit ray angle of the marginal ray, thus enabling a reduction in the overall length of the lens.

[0056] In this case, it is preferred that the back group, starting from the object side, consists of a positive single lens, a cemented lens formed by exactly one positive lens and exactly one negative lens cemented together, and a single lens with a negative meniscus shape whose concave surface faces the object side. This configuration allows the back group to achieve high optical performance with the minimum number of lenses, thus reducing the overall length of the objective and lowering costs.

[0057] It is preferred that the first lens group G1, starting from the object side, consists of a negative lens, a positive lens, a positive lens, and a positive lens. The first lens group G1, comprising three positive lenses in this manner, allows for the successful correction of chromatic and spherical aberrations, particularly at the telephoto end. In cases where the first lens group G1 is designed as a whole with a strong refractive power for purposes of magnification, etc., the configuration described above still allows the refractive power to be distributed across the lenses, thereby reducing aberrations occurring at each lens surface.

[0058] It is preferred if focusing from an object at infinity to the nearest object is achieved by moving only the entire third lens group G3 (the mp lens group) or a portion of the lenses forming the third lens group G3 (the mp lens group) along the optical axis. Using the internal focusing system described above allows for a reduction in the weight of the focusing lens, thereby accelerating the autofocus operation. Furthermore, achieving focus by moving the entire third lens group G3 (the mp lens group) allows for the suppression of aberration variations during focusing.

[0059] It is preferred if the following condition expression (3) is satisfied. Satisfying the lower limit of condition expression (3) prevents the refractive power of the front group from becoming excessively weak. This allows the incident ray height on the center group, which is the image stabilization lens group, to be kept small and the center group to have a strong refractive power, which is advantageous for reducing the size of the image stabilization lens unit. This is also advantageous for reducing the overall length of the lens. Satisfying the upper limit of condition expression (3) prevents the refractive power of the front group from becoming excessively strong, and this is advantageous for correcting spherical aberration and coma. It should be noted that higher performance can be obtained if the following condition expression (3-1) is satisfied. 0.5 <FGr1 / FGr<1,3 0.58 <FGr1 / FGr<1,15 where FGr1 is a focal length of the front group of the furthest rear lens group and FGr is a focal length of the furthest rear lens group.

[0060] It is preferred if the following condition expression (4) is satisfied. Satisfying the lower limit of condition expression (4) prevents the refractive power of the front group from becoming excessively weak. This allows the incident ray height on the center group, which is the image stabilization lens group, to be kept small and the center group to have a strong refractive power, which is advantageous for reducing the size of the image stabilization lens unit. This is also advantageous for reducing the overall length of the lens. Satisfying the upper limit of condition expression (4) prevents the refractive power of the front group from becoming excessively strong, and this is advantageous for correcting spherical aberration and coma. It should be noted that higher performance can be obtained if the following condition expression (4-1) is satisfied. 0.25 <FGr1 / Ft<0,60 0.29 <FGr1 / Ft<0,55 where FGr1 is a focal length of the front group of the furthest rear lens group and Ft is a focal length of the entire system when the zoom lens at the telephoto end is focused on an object at infinity.

[0061] It is preferred if the following condition expression (5) is satisfied. Satisfying the lower limit of condition expression (5) prevents the refractive power of the rear group from becoming excessively strong, which is advantageous for correcting coma and distortion. Satisfying the upper limit of condition expression (5) prevents the refractive power of the rear group from becoming excessively weak. This is advantageous for reducing the overall length of the lens and simplifies providing the center group, which is the image stabilization lens group, with a strong refractive power. It should be noted that higher performance can be obtained if the following condition expression (5-1) is satisfied. 0.12 <FGr3 / Ft<0,27 0.14 <FGr3 / Ft<0,25 where FGr3 is a focal length of the rear group of the rearmost lens group and Ft is a focal length of the entire system when the zoom lens at the telephoto end is focused on an object at infinity.

[0062] It is preferred if the following condition expression (6) is satisfied. Satisfying the lower limit of condition expression (6) simplifies ensuring a flange focal distance necessary for an interchangeable-lens camera and eliminates the need to provide each lens group with a strong refractive power for size reduction purposes, thereby simplifying aberration correction. Satisfying the upper limit of condition expression (6) is advantageous for reducing the overall length of the lens. It should be noted that higher performance can be obtained if the following condition expression (6-1) is satisfied. 0.12 <BF / Ft<0,28 0.14 <BF / Ft<0,25 where BF is an equivalent air distance from the furthest rear lens group to the image plane and Ft is a focal length of the entire system when the zoom lens at the telephoto end is focused on an object at infinity.

[0063] It is preferred if the following condition expression (7) is satisfied. Satisfying the lower bound of condition expression (7) simplifies ensuring optical performance. Satisfying the upper bound of condition expression (7) is advantageous for reducing the size of the lens system. It should be noted that higher performance can be obtained if the following condition expression (7-1) is satisfied. 1.1 <TL / Ft<1,6 1.15 <TL / Ft<1,55 where TL is the total length of the optical system and Ft is the focal length of the entire system when the zoom lens at the telephoto end is focused on an object at infinity.

[0064] It is preferred if the zoom lens according to the invention consists of four lens groups, which, starting from the object side, comprise the first lens group, the second lens group, the mp lens group, and the rearmost lens group. Minimizing the number of lens groups and designing the zoom lens with the four-group configuration described above allows for a simplification of the frame structure and a reduction in the influence of decentering.

[0065] If the zoom lens is used in a harsh environment, it is preferable if it has a multi-layer protective coating. In addition to the protective coating, the zoom lens can also be equipped with an anti-reflective coating to reduce ghosting, etc., during use.

[0066] In the Fig.In the example shown, the optical element PP is positioned between the lens system and the imaging plane Sim. However, instead of placing the various filters, such as a low-pass filter and a filter that cuts off a specific wavelength range, between the lens system and the imaging plane Sim, the various filters can be positioned between the lenses, or coatings with the same functions as the various filters can be applied to the lens surfaces of some of the lenses.

[0067] Numerical examples of the zoom lens according to the invention are described below.

[0068] First, a zoom lens from Example 1 will be described. Fig. Figure 1 is a sectional view illustrating the lens configuration of the zoom lens from Example 1.

[0069] It should be noted that in Fig. 1 and Fig.Figures 2 to 9, which correspond to examples 2 to 9 and are described later, show the left side as the object side and the right side as the image side. The aperture stop St shown in the drawings does not necessarily represent its size or shape, but rather its position along the optical axis Z. In the drawings, the symbol "FOCUS" denotes a focusing lens group used to achieve focusing, and the symbol "Ois" denotes an image stabilization lens group used to achieve image stabilization.

[0070] The zoom lens of Example 1 has a four-group configuration, which, starting from the object side, consists of a first lens group G1 with a positive refractive power, a second lens group G2 with a negative refractive power, a third lens group G3 (the mp lens group) with a positive refractive power, and a fourth lens group G4 (the furthest rear lens group) with a positive refractive power.

[0071] Table 1 shows basic lens data for the zoom lens of Example 1, Table 2 shows data on specifications of the zoom lens, and Table 3 shows data on distances between moving surfaces of the zoom lens. The following description explains the meanings of the symbols used in the tables with respect to Example 1. The same explanations generally apply to those relating to Examples 2 through 9.

[0072] In the lens data shown in Table 1, each value in the "Surface No." column represents a surface number, where the object-side surface of the element furthest from the object is the first surface and the number is incremented sequentially towards the image side. Each value in the "Radius of Curvature" column represents the radius of curvature of the corresponding surface, and each value in the "Spacing Distance" column represents the distance along the optical axis Z between the respective surface and the next surface. Each value in the "nd" column represents the refractive index of the corresponding optical element with respect to the d-line (wavelength of 587.6 nm), each value in the "vd" column represents the Abbe number of the corresponding optical element with respect to the d-line (wavelength of 587.6 nm), and each value in the "θgF" column represents the partial dispersion ratio of the corresponding optical element.

[0073] It should be noted that the partial dispersion ratio θgF is represented by the following formula: θgF=(ng−nF) / (nF−nC), where ng is a refractive index with respect to the g-line (the wavelength of 435.8 nm), nF is a refractive index with respect to the F-line (the wavelength of 486.1 nm) and nC is a refractive index with respect to the C-line (the wavelength of 656.3 nm).

[0074] The sign for the radius of curvature is specified such that a positive radius of curvature indicates a surface shape that is convex towards the object side, and a negative radius of curvature indicates a surface shape that is convex towards the image side. The basic lens data also includes aperture diaphragm (St) and optical element (PP) data, and the surface number and the text "(Aperture)" are shown in the surface number column at the position corresponding to the aperture diaphragm (St). In the lens data shown in Table 1, the value of each surface distance that changes during magnification is represented by the symbol "DD[Surface Number]". The numerical values ​​corresponding to each DD[Surface Number] at the wide-angle end, the center position, and the telephoto end are shown in Table 3.

[0075] The specifications shown in Table 2 include values ​​for zoom magnification, focal length f', back focus Bf', F-number Fno, and total angle of view 2ω at the wide-angle end, the middle position, and the telephoto end.

[0076] Regarding the basic lens data, the data on specifications, and the data on distances to moving surfaces, the angular unit is degrees and the length unit is millimeters; however, any other suitable units can be used, as optical systems are usable when scaled up or down proportionally. [Table 1] Example 1 - Lens data Surface No. radius of curvature Surface distance and vd θgF 1 274,96102 2,390 1,80100 34,97 0,58642 2 77,90148 7,850 1,49700 81,54 0,53748 3 -1203,47290 0,200 4 97,12166 5,000 1,43875 94,94 0,53433 5 3892,40898 0,200 6 62,76476 6,000 1,49700 81,54 0,53748 7 583,05158 DD[7] 8 110,71627 5,710 1,72047 34,71 0,58350 9 -42,66766 1,550 1,62230 53,17 0,55424 10 24,37958 4,958 11 -78,43069 1,260 1,49700 81,54 0,53748 12 25,54612 5,501 1,84661 23,88 0,62072 13 105,31259 4,001 14 -28,87373 1,250 1,91082 35,25 0,58224 15 391,32559 DD

[15] 16 -349,16836 2,950 1,80100 34,97 0,58642 17 -38,22034 0,100 18 63,65733 4,310 1,61800 63,33 0,54414 19 -39,25049 1,150 1,80518 25,42 0,61616 20 ∞ DD

[20] 21 (aperture) ∞ 1,300 22 27,59915 6,985 1,49700 81,54 0,53748 23 -58,46986 0,150 24 34,60348 2,550 1,65412 39,68 0,57378 25 95,96990 1,610 26 -53,62431 1,210 1,90366 31,31 0,59481 27 22,84961 6,512 1,49700 81,54 0,53748 28 -84,57206 2,500 29 293,69564 3,771 1,80518 25,42 0,61616 30 -23,04083 0,950 1,58913 61,13 0,54067 31 33,63593 2,693 32 -43,53615 1,050 1,80100 34,97 0,58642 33 62,25169 3,752 34 51,53927 6,921 1,80000 29,84 0,60178 35 -39,86271 3,848 36 50,27571 7,368 1,48749 70,24 0,53007 37 -26,02866 1,310 1,80518 25,42 0,61616 38 -69,72800 3,069 39 -30,18711 1,310 1,91082 35,25 0,58224 40 -51,30966 26,063 41 ∞ 2,850 1,51633 64,14 0,53531 42 ∞ [Table 2] Example 1 - Specifications (d-line) Wide-angle end center End of phone Zoom magnification 1,0 1,8 2,6 f' 51,517 92,224 135,968 Bf' 29,940 29,940 29,940 FNo. 2,88 2,89 2,88 2ω[°] 30,4 17,0 11,6 [Table 3] Example 1 - Distances with respect to zoom Wide-angle end center End of phone DD[7] 1,647 24,961 34,686 DD

[15] 11,849 7,355 2,477 DD

[20] 32,001 13,182 8,334

[0077] Fig. Figure 10 shows aberration diagrams of the zoom lens from Example 1. The in Fig.The 10 aberration diagrams shown above are those of spherical aberration, offense against the sine condition, astigmatism, distortion, and lateral chromatic aberration at the wide-angle end, in that order starting from the left side, which is in the middle. Fig. The 10 aberration diagrams shown are those of spherical aberration, violation of the sine condition, astigmatism, distortion, and lateral chromatic aberration at the center position, in that order starting from the left, and those in Fig.The 10 aberration diagrams shown below are those of spherical aberration, violation of the sine condition, astigmatism, distortion, and lateral chromatic aberration at the telephoto end, in that order starting from the left. The aberration diagrams for spherical aberration, violation of the sine condition, astigmatism, and distortion show those with respect to the d-line (wavelength 587.6 nm), which is used as a reference wavelength. The aberration diagrams for spherical aberration show those with respect to the d-line (wavelength 587.6 nm), the C-line (wavelength 656.3 nm), the F-line (wavelength 486.1 nm), and the g-line (wavelength 435.8 nm), each represented by a solid line, a long dashed line, a short dashed line, and a gray line, respectively.The aberration diagrams for astigmatism show those in the sagittal and tangential directions, each represented by a solid line and a short dashed line. The aberration diagrams for lateral chromatic aberration show those for the C-line (wavelength 656.3 nm), the F-line (wavelength 486.1 nm), and the g-line (wavelength 435.8 nm), each represented by a long dashed line, a short dashed line, and a gray line. It should be noted that these longitudinal aberration diagrams show aberrations when the zoom lens is focused on an object at infinity. In the aberration diagrams for spherical aberration and violation of the sine condition, the symbol "FNo." denotes the "F-number," and in the other aberration diagrams, the symbol "ω" denotes the "half-angle of view."

[0078] Fig.Figure 19 shows lateral aberration diagrams of the zoom lens from Example 1 without image stabilization. Fig. Figure 19 shows, in order from top to bottom, lateral aberration diagrams at the wide-angle end, the center position, and the telephoto end. Of the lateral aberration diagrams shown in two columns, the left-hand diagrams show aberrations in the tangential direction, and the right-hand diagrams show aberrations in the sagittal direction. Of the lateral aberration diagrams, the top one shows aberrations at the center of the image plane, the two in the middle show aberrations at the position where the image height is 80% of the maximum image height on the positive (+) side, and the two at the bottom show aberrations at the position where the image height is 80% of the maximum image height on the negative (-) side. Fig.Figure 20 shows lateral aberration diagrams of the zoom lens from Example 1 with image stabilization. The contents of the aberration diagrams are similar to or identical to those without image stabilization. It should be noted that in Fig. 19 and Fig. Twenty aberrations with respect to the d-line (wavelength 587.6 nm), the C-line (wavelength 656.3 nm), the F-line (wavelength 486.1 nm), and the g-line (wavelength 435.8 nm) are shown, each represented by a solid line, a long dashed line, a short dashed line, and a gray line, respectively. These lateral aberration diagrams show lateral aberrations when the zoom lens is focused on an object at infinity. The symbol "ω" in the aberration diagrams means "half field of view."

[0079] The symbols, meanings and descriptions of the various data from Example 1 described above also apply to the examples described below, unless otherwise stated, and the same explanations are not repeated in the following description.

[0080] The following describes a zoom lens from Example 2. The zoom lens from Example 2 has a lens group configuration similar to that of the zoom lens from Example 1. Fig. Figure 2 is a sectional view illustrating the lens configuration of the zoom lens from Example 2. Table 4 shows basic lens data for the zoom lens from Example 2, Table 5 shows data on the specifications of the zoom lens, and Table 6 shows data on the distances between moving surfaces of the zoom lens. Fig. Figure 11 shows aberration diagrams of the zoom lens, Fig.Figure 21 shows lateral aberration diagrams of the zoom lens without image stabilization and Fig. Figure 22 shows lateral aberration diagrams of the zoom lens with image stabilization. [Table 4] Example 2 - Lens data Surface No. radius of curvature Surface distance and vd θgF 1 147,14684 2,312 1,90366 31,31 0,59481 2 71,34579 6,799 1,49700 81,54 0,53748 3 4466,14983 0,262 4 82,92060 4,599 1,45562 91,31 0,53429 5 222,61947 0,209 6 72,46651 7,001 1,48749 70,24 0,53007 7 2229,87611 DD[7] 8 83,14047 6,305 1,64769 33,79 0,59393 9 -54,99973 1,501 1,61772 49,81 0,56035 10 22,65737 6,228 11 -129,46710 1,009 1,53775 74,70 0,53936 12 23,41440 5,501 1,84661 23,88 0,62072 13 90,28797 3,246 14 -32,56444 0,999 1,91082 35,25 0,58224 15 -754,10763 DD

[15] 16 -139,28102 3,100 1,91082 35,25 0,58224 17 -37,20322 0,100 18 45,57357 5,511 1,48749 70,24 0,53007 19 -45,00113 1,100 1,80518 25,42 0,61616 20 302,73331 DD

[20] 21 (aperture) ∞ 1,300 22 29,00638 5,564 1,53775 74,70 0,53936 23 -83,12098 0,182 24 28,22418 2,499 1,65412 39,68 0,57378 25 48,84185 1,900 26 -76,98887 1,210 1,90366 31,31 0,59481 27 20,91613 7,501 1,53775 74,70 0,53936 28 -71,39743 3,663 29 101,15891 4,706 1,80518 25,42 0,61616 30 -24,63022 0,882 1,60300 65,44 0,54022 31 26,11599 3,199 32 -41,59530 0,899 1,80100 34,97 0,58642 33 49,70954 2,255 34 43,72156 5,600 1,80000 29,84 0,60178 35 -36,00246 2,992 36 36,16338 5,708 1,48749 70,24 0,53007 37 -25,22381 1,199 1,80518 25,42 0,61616 38 -148,78795 4,102 39 -27,60609 1,199 1,91082 35,25 0,58224 40 -43,25152 23,562 41 ∞ 2,850 1,51633 64,14 0,53531 42 ∞ [Table 5] Example 2 - Specifications (d-line) Wide-angle end center End of phone Zoom magnification 1,0 1,8 2,6 f' 51,492 92,178 135,901 Bf' 27,440 27,440 27,440 FNo. 2,89 2,89 2,89 2ω[°] 30,2 17,0 11,6 [Table 6] Example 2 - Distances with respect to zoom Wide-angle end center End of phone DD[7] 1,199 24,644 34,908 DD

[15] 12,356 7,391 1,751 DD

[20] 31,802 13,322 8,698

[0081] The following describes a zoom lens from Example 3. The zoom lens from Example 3 has a lens group configuration similar to that of the zoom lens from Example 1. Fig. Figure 3 is a sectional view illustrating the lens configuration of the zoom lens in Example 3. Table 7 shows basic lens data for the zoom lens in Example 3, Table 8 shows data on the specifications of the zoom lens, and Table 9 shows data on the distances between moving surfaces of the zoom lens. Fig.Figure 12 shows aberration diagrams of the zoom lens. Fig. Figure 23 shows lateral aberration diagrams of the zoom lens without image stabilization and Fig. Figure 24 shows lateral aberration diagrams of the zoom lens with image stabilization. [Table 7] Example 3 - Lens data Surface No. radius of curvature Surface distance and vd θgF 1 263,09263 2,312 1,88100 40,14 0,57010 2 65,86876 7,199 1,49700 81,54 0,53748 3 -571,64100 0,262 4 65,97392 6,200 1,45562 91,31 0,53429 5 1175,27258 0,209 6 81,36467 5,500 1,53775 74,70 0,53936 7 614,16494 DD[7] 8 120,18724 5,912 1,72047 34,71 0,58350 9 -42,77946 1,200 1,62230 53,17 0,55424 10 26,30170 5,468 11 -3031,67199 1,009 1,43875 94,94 0,53433 12 24,69032 4,403 1,84661 23,88 0,62072 13 52,10852 4,001 14 -29,01944 0,999 1,88300 40,76 0,56679 15 677,75184 DD

[15] 16 -624,58221 3,099 1,91082 35,25 0,58224 17 -48,99609 0,100 18 84,61141 4,859 1,62041 60,29 0,54266 19 -45,52887 1,100 1,84666 23,78 0,62054 20 -11814,82817 DD

[20] 21 (aperture) ∞ 1,300 22 28,94841 7,001 1,49700 81,54 0,53748 23 -70,94964 2,298 24 35,48837 2,499 1,65412 39,68 0,57378 25 125,19811 1,799 26 -55,44889 1,210 1,90366 31,31 0,59481 27 24,47948 7,501 1,49700 81,54 0,53748 28 -71,45146 2,001 29 93,11345 4,160 1,80518 25,42 0,61616 30 -26,87211 0,849 1,58313 59,37 0,54345 31 26,83474 3,501 32 -31,98401 0,901 1,80100 34,97 0,58642 33 64,79704 2,718 34 52,34160 5,499 1,80000 29,84 0,60178 35 -36,46191 4,001 36 56,45949 7,310 1,48749 70,24 0,53007 37 -23,44294 1,199 1,80518 25,42 0,61616 38 -60,82914 2,999 39 -26,37941 1,199 1,91082 35,25 0,58224 40 -35,96318 22,238 41 ∞ 2,850 1,51633 64,14 0,53531 42 ∞ [Table 8] Example 3 - Specifications (d-line) Wide-angle end center End of phone Zoom magnification 1,0 1,8 3,1 f' 50,359 90,150 157,119 Bf' 26,122 26,122 26,122 FNo. 2,89 2,90 2,92 2ω[°] 31,0 17,2 10,0 [Table 9] Example 3 - Distances with respect to zoom Wide-angle end center End of phone DD[7] 1,199 24,327 37,203 DD

[15] 16,502 10,829 1,100 DD

[20] 32,001 14,546 11,399

[0082] The following describes a zoom lens from Example 4. The zoom lens from Example 4 has a lens group configuration similar to that of the zoom lens from Example 1. Fig.Figure 4 is a sectional view illustrating the lens configuration of the zoom lens in Example 4. Table 10 shows basic lens data for the zoom lens in Example 4, Table 11 shows data on the specifications of the zoom lens, and Table 12 shows data on the distances between moving surfaces of the zoom lens. Fig. Figure 13 shows aberration diagrams of the zoom lens, Fig. Figure 25 shows lateral aberration diagrams of the zoom lens without image stabilization and Fig. Figure 26 shows lateral aberration diagrams of the zoom lens with image stabilization. [Table 10] Example 4 - Lens data Surface No. radius of curvature Surface distance and vd θgF 1 188,13090 2,312 1,80610 33,27 0,58845 2 76,50883 7,200 1,49700 81,54 0,53748 3 -3204,67292 0,262 4 71,91851 6,200 1,43875 94,94 0,53433 5 718,81472 0,209 6 63,83157 5,500 1,43875 94,94 0,53433 7 286,11890 DD[7] 8 127,11673 5,510 1,72047 34,71 0,58350 9 -52,90722 1,200 1,62230 53,17 0,55424 10 24,99227 6,501 11 -273,45110 1,511 1,59522 67,74 0,54426 12 26,07897 5,501 1,84661 23,88 0,62072 13 90,43692 4,000 14 -28,20939 1,001 1,88300 40,76 0,56679 15 -219,42843 DD

[15] 16 4368,42118 3,099 1,91082 35,25 0,58224 17 -45,70178 0,100 18 75,53670 5,511 1,49700 81,54 0,53748 19 -37,32451 1,100 1,80518 25,42 0,61616 20 -582,89400 DD

[20] 21 (aperture) ∞ 1,300 22 31,57617 7,001 1,49700 81,54 0,53748 23 -84,25408 1,501 24 32,66369 2,500 1,65412 39,68 0,57378 25 452,11337 1,799 26 -77,71874 1,210 1,90366 31,31 0,59481 27 23,15115 5,500 1,49700 81,54 0,53748 28 -93,31207 2,001 29 664,84163 4,161 1,80518 25,42 0,61616 30 -28,96139 1,201 1,58313 59,37 0,54345 31 23,87736 3,200 32 -37,84433 0,899 1,80100 34,97 0,58642 33 66,37072 2,215 34 45,41616 8,001 1,80518 25,42 0,61616 35 -36,36637 1,453 36 44,07982 7,310 1,48749 70,24 0,53007 37 -23,31946 1,200 1,80518 25,42 0,61616 38 -147,09849 2,999 39 -27,43891 1,200 1,91082 35,25 0,58224 40 -35,75126 22,213 41 ∞ 2,850 1,51633 64,14 0,53531 42 ∞ [Table 11] Example 4 - Specifications (d-line) Wide-angle end center End of phone Zoom magnification 1,0 1,8 3,0 f' 51,153 91,572 154,995 Bf' 26,096 26,096 26,096 FNo. 2,89 2,89 2,89 2ω[°] 30,6 17,2 10,2 [Table 12] Example 4 - Distances with respect to zoom Wide-angle end center End of phone DD[7] 1,199 22,851 34,047 DD

[15] 17,079 11,080 1,673 DD

[20] 28,994 13,341 11,552

[0083] The following describes a zoom lens from Example 5. The zoom lens from Example 5 has a lens group configuration similar to that of the zoom lens from Example 1. Fig. Figure 5 is a sectional view illustrating the lens configuration of the zoom lens in Example 5. Table 13 shows basic lens data for the zoom lens in Example 5, Table 14 shows data on the specifications of the zoom lens, and Table 15 shows data on the distances between moving surfaces of the zoom lens. Fig. Figure 14 shows aberration diagrams of the zoom lens, Fig. Figure 27 shows lateral aberration diagrams of the zoom lens without image stabilization and Fig. Figure 28 shows lateral aberration diagrams of the zoom lens with image stabilization. [Table 13] Example 5 - Lens data Surface No. radius of curvature Surface distance and vd IgF 1 379,59503 2,390 1,80100 34,97 0,58642 2 87,06343 7,850 1,49700 81,54 0,53748 3 -423,40525 0,200 4 77,08956 6,600 1,43875 94,94 0,53433 5 505,15031 0,200 6 74,14509 4,950 1,49700 81,54 0,53748 7 428,65265 DD[7] 8 95,00168 5,710 1,72047 34,71 0,58350 9 -42,18184 1,550 1,62230 53,17 0,55424 10 25,82252 4,852 11 -127,50772 1,260 1,49700 81,54 0,53748 12 27,56506 4,000 1,84661 23,88 0,62072 13 102,12490 3,395 14 -31,04306 1,250 1,91082 35,25 0,58224 15 593,08219 DD

[15] 16 -587,37289 2,950 1,80100 34,97 0,58642 17 -43,88242 0,100 18 78,12881 4,310 1,61800 63,33 0,54414 19 -42,34007 1,150 1,80518 25,42 0,61616 20 ∞ DD

[20] 21 (aperture) ∞ 1,300 22 27,72433 6,373 1,49700 81,54 0,53748 23 -59,65321 0,150 24 34,01198 2,550 1,65412 39,68 0,57378 25 93,88248 1,610 26 -54,41210 1,210 1,90366 31,31 0,59481 27 23,35543 5,569 1,49700 81,54 0,53748 28 -77,98799 2,500 29 394,61491 3,771 1,80518 25,42 0,61616 30 -24,49939 0,950 1,58913 61,13 0,54067 31 37,65964 2,511 32 -48,39346 1,050 1,80100 34,97 0,58642 33 60,29812 4,948 34 52,39389 5,299 1,80000 29,84 0,60178 35 -39,28541 3,134 36 53,75550 7,501 1,48749 70,24 0,53007 37 -26,62926 1,310 1,80518 25,42 0,61616 38 -98,73317 6,921 39 -26,89205 1,310 1,91082 35,25 0,58224 40 -46,99846 18,856 41 ∞ 2,850 1,51633 64,14 0,53531 42 ∞ [Table 14] Example 5 - Specifications (d-line) Wide-angle end center End of phone Zoom magnification 1,0 1,8 2,4 f' 51,515 92,219 125,696 Bf' 22,736 22,736 22,736 FNo. 2,88 2,89 2,88 2ω[°] 30,4 17,0 12,4 [Table 15] Example 5 - Distances with respect to zoom Wide-angle end center End of phone DD[7] 1,199 26,087 34,640 DD

[15] 13,697 7,573 2,495 DD

[20] 32,001 13,236 9,762

[0084] The following describes a zoom lens from Example 6. The zoom lens from Example 6 has a lens group configuration similar to that of the zoom lens from Example 1. Fig. Figure 6 is a sectional view illustrating the lens configuration of the zoom lens in Example 6. Table 16 shows basic lens data for the zoom lens in Example 6, Table 17 shows data on the specifications of the zoom lens, and Table 18 shows data on the distances between moving surfaces of the zoom lens. Fig. Figure 15 shows aberration diagrams of the zoom lens, Fig. Figure 29 shows lateral aberration diagrams of the zoom lens without image stabilization and Fig. Figure 30 shows lateral aberration diagrams of the zoom lens with image stabilization. [Table 16] Example 6 - Lens data Surface No. radius of curvature Surface distance and vd θgF 1 358,57195 2,320 1,80100 34,97 0,58642 2 85,09780 7,200 1,49700 81,54 0,53748 3 -386,19076 0,200 4 72,25745 6,972 1,43875 94,94 0,53433 5 ∞ 0,200 6 69,93587 5,200 1,49700 81,54 0,53748 7 235,70554 DD[7] 8 96,21157 6,291 1,72047 34,71 0,58350 9 -43,59489 1,530 1,62230 53,17 0,55424 10 24,59706 5,600 11 -73,29120 1,410 1,49700 81,54 0,53748 12 27,09637 4,000 1,84661 23,88 0,62072 13 123,98633 2,799 14 -30,96977 1,200 1,91082 35,25 0,58224 15 353,74684 DD

[15] 16 -406,80952 2,850 1,80100 34,97 0,58642 17 -43,60631 0,100 18 74,86402 4,260 1,61800 63,33 0,54414 19 -43,68363 1,170 1,80518 25,42 0,61616 20 ∞ DD

[20] 21 (aperture) ∞ 1,300 22 28,04424 7,050 1,49700 81,54 0,53748 23 -59,60296 0,150 24 34,77250 2,570 1,65412 39,68 0,57378 25 89,21437 1,800 26 -51,39895 1,110 1,90366 31,31 0,59481 27 24,25217 5,266 1,49700 81,54 0,53748 28 -60,88125 2,800 29 733,80887 3,771 1,80518 25,42 0,61616 30 -23,29690 0,950 1,58913 61,13 0,54067 31 39,10301 2,801 32 -39,71546 1,000 1,80100 34,97 0,58642 33 62,34880 4,199 34 54,23606 5,285 1,80000 29,84 0,60178 35 -37,12789 4,367 36 51,75623 6,461 1,48749 70,24 0,53007 37 -25,77385 1,310 1,80518 25,42 0,61616 38 -86,83396 4,400 39 -27,43970 1,260 1,91082 35,25 0,58224 40 -40,98080 25,514 41 ∞ 2,850 1,51633 64,14 0,53531 42 ∞ [Table 17] Example 6 - Specifications (d-line) Wide-angle end center End of phone Zoom magnification 1,0 1,8 2,6 f' 51,516 92,222 135,965 Bf' 29,393 29,393 29,393 FNo. 2,88 2,89 2,88 2ω[°] 30,6 17,0 11,6 [Table 18] Example 6 - Distances with respect to zoom Wide-angle end center End of phone DD[7] 1,191 22,931 32,107 DD

[15] 14,409 8,821 2,687 DD

[20] 29,090 12,939 9,896

[0085] The following describes a zoom lens from Example 7. The zoom lens from Example 7 has a five-group configuration, which, starting from the object side, consists of a first lens group G1 with a positive refractive power, a second lens group G2 with a negative refractive power, a third lens group G3 with a negative refractive power, a fourth lens group G4 (the mp lens group) with a positive refractive power, and a fifth lens group G5 (the furthest rear lens group) with a positive refractive power. Fig.Figure 7 is a sectional view illustrating the lens configuration of the zoom lens in Example 7. Table 19 shows basic lens data for the zoom lens in Example 7, Table 20 shows data on the specifications of the zoom lens, and Table 21 shows data on the distances between moving surfaces of the zoom lens. Fig. Figure 16 shows aberration diagrams of the zoom lens, Fig. Figure 31 shows lateral aberration diagrams of the zoom lens without image stabilization and Fig. Figure 32 shows lateral aberration diagrams of the zoom lens with image stabilization. [Table 19] Example 7 - Lens data Surface No. radius of curvature Surface distance and vd θgF 1 303,47850 2,390 1,80100 34,97 0,58642 2 75,71759 7,850 1,49700 81,54 0,53748 3 -338,62836 0,200 4 67,27723 6,600 1,43875 94,94 0,53433 5 706,55071 0,200 6 67,16666 4,950 1,49700 81,54 0,53748 7 287,46150 DD[7] 8 98,18370 5,710 1,72047 34,71 0,58350 9 -49,05401 1,550 1,62230 53,17 0,55424 10 24,62771 DD

[10] 11 -75,51985 1,260 1,49700 81,54 0,53748 12 25,58057 5,388 1,84661 23,88 0,62072 13 106,72525 3,704 14 -31,24101 1,250 1,91082 35,25 0,58224 15 268,03486 DD

[15] 16 -521,95122 2,950 1,80100 34,97 0,58642 17 -44,70833 0,100 18 73,37158 4,310 1,61800 63,33 0,54414 19 -43,22381 1,150 1,80518 25,42 0,61616 20 ∞ DD

[20] 21 (aperture) ∞ 1,300 22 27,81729 6,868 1,49700 81,54 0,53748 23 -57,84476 0,150 24 34,09999 2,550 1,65412 39,68 0,57378 25 102,68991 1,610 26 -54,83237 1,210 1,90366 31,31 0,59481 27 23,14151 5,662 1,49700 81,54 0,53748 28 -87,93105 2,500 29 372,91281 3,771 1,80518 25,42 0,61616 30 -24,31863 0,950 1,58913 61,13 0,54067 31 36,29877 3,256 32 -44,08151 1,050 1,80100 34,97 0,58642 33 60,80519 3,831 34 50,53032 5,748 1,80000 29,84 0,60178 35 -39,43779 4,000 36 48,86127 8,012 1,48749 70,24 0,53007 37 -26,40743 1,310 1,80518 25,42 0,61616 38 -86,68447 3,157 39 -27,70770 1,310 1,91082 35,25 0,58224 40 -44,10429 24,901 41 ∞ 2,850 1,51633 64,14 0,53531 42 ∞ [Table 20] Example 7 - Specifications (d-line) Wide-angle end center End of phone Zoom magnification 1,0 1,8 2,6 f' 51,514 92,218 135,960 Bf' 28,781 28,781 28,781 FNo. 2,88 2,89 2,88 2ω[°] 30,4 17,0 11,6 [Table 21] Example 7 - Distances with respect to zoom Wide-angle end center End of phone DD[7] 1,199 20,933 29,242 DD

[10] 6,235 6,638 6,783 DD

[15] 14,153 8,593 2,488 DD

[20] 26,710 12,132 9,785

[0086] The following describes a zoom lens from Example 8. The zoom lens from Example 8 has a lens group configuration similar to that of the zoom lens from Example 7. Fig. Figure 8 is a sectional view illustrating the lens configuration of the zoom lens in Example 8. Table 22 shows basic lens data for the zoom lens in Example 8, Table 23 shows data on the specifications of the zoom lens, and Table 24 shows data on the distances between moving surfaces of the zoom lens. Fig. Figure 17 shows aberration diagrams of the zoom lens, Fig. Figure 33 shows lateral aberration diagrams of the zoom lens without image stabilization and Fig. Figure 34 shows lateral aberration diagrams of the zoom lens with image stabilization. [Table 22] Example 8 - Lens data Surface No. radius of curvature Surface distance and vd θgF 1 257,91881 2,390 1,83400 37,16 0,57759 2 73,18612 7,850 1,49700 81,54 0,53748 3 -329,42308 0,200 4 62,30117 6,600 1,43700 95,10 0,53364 5 849,43043 0,200 6 72,87230 4,950 1,49700 81,54 0,53748 7 263,78540 DD[7] 8 107,78333 5,710 1,72047 34,71 0,58350 9 -47,76821 1,550 1,62230 53,17 0,55424 10 25,18309 5,631 11 -93,23488 1,260 1,49700 81,54 0,53748 12 26,34063 3,999 1,84661 23,88 0,62072 13 99,67576 DD

[13] 14 -31,09640 1,250 1,91082 35,25 0,58224 15 318,83279 DD

[15] 16 -974,57258 2,950 1,80100 34,97 0,58642 17 -43,76266 0,100 18 65,14269 4,310 1,53775 74,70 0,53936 19 -49,97731 1,150 1,80518 25,42 0,61616 20 ∞ DD

[20] 21 (aperture) ∞ 1,300 22 28,69392 7,001 1,49700 81,54 0,53748 23 -59,87797 0,150 24 34,09590 2,550 1,65412 39,68 0,57378 25 85,63948 1,610 26 -54,93056 1,210 1,90366 31,31 0,59481 27 24,95033 6,359 1,49700 81,54 0,53748 28 -76,31225 2,500 29 141,63653 3,771 1,80518 25,42 0,61616 30 -23,83965 0,950 1,58913 61,13 0,54067 31 30,73799 2,499 32 -37,50492 1,050 1,80100 34,97 0,58642 33 53,05759 2,617 34 55,65453 6,802 1,83400 37,16 0,57759 35 -41,09507 4,001 36 52,54294 6,611 1,48749 70,24 0,53007 37 -38,16059 1,310 1,80518 25,42 0,61616 38 -57,00236 3,270 39 -28,19030 1,310 1,91082 35,25 0,58224 40 -47,93144 28,451 41 ∞ 2,850 1,51633 64,14 0,53531 42 ∞ [Table 23] Example 8 - Specifications (d-line) Wide-angle end center End of phone Zoom magnification 1,0 1,8 2,6 f' 51,526 92,240 135,992 Bf' 32,332 32,332 32,332 FNo. 2,88 2,89 2,88 2ω[°] 30,4 17,0 11,6 [Table 24] Example 8 - Distances with respect to zoom Wide-angle end center End of phone DD[7] 1,199 21,287 29,769 DD

[13] 4,000 4,585 4,348 DD

[15] 14,542 8,794 2,472 DD

[20] 26,846 11,921 9,998

[0087] The following describes a zoom lens from Example 9. The zoom lens from Example 9 has a lens group configuration similar to that of the zoom lens from Example 1. Fig. Figure 9 is a sectional view illustrating the lens configuration of the zoom lens in Example 9. Table 25 shows basic lens data for the zoom lens in Example 9, Table 26 shows data on the specifications of the zoom lens, and Table 27 shows data on the distances between moving surfaces of the zoom lens. Fig. Figure 18 shows aberration diagrams of the zoom lens, Fig. Figure 35 shows lateral aberration diagrams of the zoom lens without image stabilization and Fig. Figure 36 shows lateral aberration diagrams of the zoom lens with image stabilization. [Table 25] Example 9 - Lens data Surface No. radius of curvature Surface distance and vd θgF 1 180,37474 2,390 1,80100 34,97 0,58642 2 69,14868 7,850 1,49700 81,54 0,53748 3 -481,66507 0,200 4 60,15068 7,500 1,43875 94,94 0,53433 5 1142,76498 0,200 6 76,86117 4,500 1,49700 81,54 0,53748 7 187,53228 DD[7] 8 111,60159 5,710 1,72047 34,71 0,58350 9 -39,89381 1,550 1,62230 53,17 0,55424 10 24,07077 4,980 11 -64,75230 1,260 1,49700 81,54 0,53748 12 24,25512 5,408 1,84661 23,88 0,62072 13 94,37171 2,799 14 -28,39083 1,250 1,91082 35,25 0,58224 15 193,35819 DD

[15] 16 -2763,02905 2,950 1,80100 34,97 0,58642 17 -42,42344 0,100 18 118,96564 4,310 1,59282 68,62 0,54414 19 -37,94715 1,150 1,84666 23,78 0,62054 20 -229,69252 7,412 21 389,16162 2,200 1,68893 31,07 0,60041 22 -215,34129 DD

[22] 23 (aperture) ∞ 1,300 24 27,53581 7,001 1,49700 81,54 0,53748 25 -57,95147 0,150 26 36,50795 2,550 1,65412 39,68 0,57378 27 105,69164 1,610 28 -54,28866 1,210 1,90366 31,31 0,59481 29 22,84035 6,968 1,49700 81,54 0,53748 30 -80,66013 2,500 31 381,31349 3,771 1,80518 25,42 0,61616 32 -25,25989 0,950 1,58913 61,13 0,54067 33 39,74943 3,501 34 -39,07424 1,050 1,80100 34,97 0,58642 35 67,59646 4,073 36 53,40416 5,837 1,80000 29,84 0,60178 37 -38,04851 4,001 38 47,49724 6,893 1,48749 70,24 0,53007 39 -27,13146 1,310 1,80518 25,42 0,61616 40 -85,37597 3,001 41 -29,19153 1,310 1,91082 35,25 0,58224 42 -47,66122 25,665 43 ∞ 2,850 1,51633 64,14 0,53531 44 ∞ [Table 26] Example 9 - Specifications (d-line) Wide-angle end center End of phone Zoom magnification 1,0 1,8 2,6 f' 51,511 92,212 135,951 Bf' 29,545 29,545 29,545 FNo. 2,88 2,89 2,88 2ω[°] 30,6 17,0 11,6 [Table 27] Example 9 - Distances with respect to zoom Wide-angle end center End of phone DD[7] 1,697 21,960 30,401 DD

[15] 10,593 6,211 1,452 DD

[22] 21,360 5,480 1,796

[0088] Table 28 shows values ​​for the zoom lenses of Examples 1 to 9 that correspond to the condition formulas (1) to (7). In all examples, the d-line is used as a reference wavelength, and the values ​​shown in Table 28 below refer to the reference wavelength. [Table 28] Nr. Conditional expression Example 1 Example 2 Example 3 Example 4 Example 5 (1) FGr3 / FGr 0,276 0,271 0,257 0,369 0,448 (2) FGr1 / FGr3 2,446 2,355 2,408 1,963 2,253 (3) FGr1 / FGr 0,676 0,639 0,619 0,724 1,010 (4) FGr1 / Ft 0,504 0,430 0,402 0,331 0,518 (5) FGr3 / Ft 0,206 0,183 0,167 0,169 0,230 (6) BF / Ft 0,220 0,202 0,166 0,169 0,181 (7) TL / Ft 1,388 1,362 1,207 1,208 1,450 Nr. Conditional expression Example 6 Example 7 Example 8 Example 9 (1) FGr3 / FGr 0,428 0,435 0,398 0,420 (2) FGr1 / FGr3 2,286 2,311 2,550 2,446 (3) FGr1 / FGr 0,978 1,006 1,015 1,027 (4) FGr1 / Ft 0,468 0,475 0,487 0,503 (5) FGr3 / Ft 0,205 0,205 0,191 0,206 (6) BF / Ft 0,216 0,212 0,238 0,217 (7) TL / Ft 1,362 1,360 1,367 1,367

[0089] As can be seen from the data described above, each of the zoom lenses of examples 1 to 9 fulfills the condition expressions (1) to (7) and is a telephoto zoom lens with an angle of view of approximately 10 to 13 degrees at the telephoto end, a zoom ratio of approximately 2.4 to 3.1, and a large aperture with a maximum aperture of approximately F2.8 over the entire zoom range and with high optical performance with high sensitivity to an image stabilization lens group and suppressed variation of aberrations during image stabilization.

[0090] An embodiment of an imaging device according to the invention is described below with reference to Fig. 37 and Fig. 38 described. Fig. 37 and Fig.Figures 38 are perspective views, each showing the front and back of a camera 30. The camera 30 is a non-reflective digital camera to which an interchangeable lens 20 is detachably attached, the lens being a zoom lens 1 according to the embodiment of the invention, which is housed in a lens tube.

[0091] The camera 30 comprises a camera body 31, and a shutter release button 32 and a power button 33 are located on the top of the camera body 31. Operating sections 34 and 35 and a display section 36 are located on the rear of the camera body 31. The display section 36 shows a captured image and an image within the field of view before an imaging operation is performed.

[0092] An imaging aperture, through which light from the subject enters, is formed at the center of the front of the camera body 31, and a mounting bracket 37 is arranged at the position corresponding to the imaging aperture. The interchangeable lens 20 is attached to the camera body 31 by means of the mounting bracket 37.

[0093] The camera body 31 contains an image sensor (not shown), such as a CCD, for receiving a subject image formed by the interchangeable lens 20 and for outputting an image signal corresponding to the subject image; a signal processing circuit for processing the image signal output by the image sensor to generate an image; a storage medium for saving the generated image; etc. With this camera 30, a still image or a moving image can be captured when the shutter release button 32 is pressed, and the image data obtained by the imaging operation is stored in the storage medium.

[0094] The camera 30 of this embodiment, which is equipped with the zoom lens 1 according to the invention, can achieve a high image stabilization effect and allows the acquisition of high-quality images.

[0095] The present invention has been described with reference to the embodiments and examples. However, the present invention is not limited to the embodiments and examples described above, and various modifications can be made to the invention. For example, the values ​​of the radius of curvature, the surface distance, the refractive index, the Abbe number, the aspheric coefficients, etc., of each lens are not limited to the values ​​shown in the examples described above and can assume other values.

[0096] While the embodiment of the imaging device is described and shown in the drawings as an example of a non-reflective (so-called mirrorless) digital camera, this is not intended to limit the imaging device according to the invention. For example, the invention is also applicable to imaging devices such as video cameras, digital cameras, cinema cameras, and broadcast cameras.

Claims

[1] Zoom lens (1) comprising as a whole four or five lens groups, which, starting from one side of the object, consist of a first lens group (G1) having a positive refractive power and remaining fixed relative to an image plane (Sim) during a change in magnification, a second lens group (G2) having a negative refractive power and moving during the change in magnification, one or two intermediate lens groups (G3, G4) comprising an mp lens group (G3 or G4) having a positive refractive power and moving during the change in magnification, and a rearmost lens group (G4 or G5) located at the image-side position of the entire system, having a positive refractive power and remaining fixed relative to the image plane (Sim) during the change in magnification, the change in magnification is achieved by changing all distances between the adjacent lens groups, the most posterior lens group (G4 or G5), in order starting from the object side, consists of an anterior group (L41 to L44 or L51 to L54) with a positive refractive power, a middle group (Ois) with a negative refractive power and a posterior group (L48 to L51 or L58 to L61) with a positive refractive power, The air gaps between the front group and the middle group, and between the middle group and the rear group, remain constant during magnification changes and focusing. the anterior group includes at least two positive lenses and at least one negative lens, Image stabilization is achieved by shifting only the center group in directions perpendicular to the direction of the optical axis (Z). wherein the Rück group comprises a cemented lens (L49, L50 or L59, L60) formed by a positive lens and a negative lens cemented together, and the following conditional expressions (1) and (2) are satisfied: 0.20 <FGr3 / FGr<0,45 1.75 <FGr1 / FGr3<3,00 where FGr3 is a focal length of the rear group of the furthest rear lens group, FGr is a focal length of the furthest rear lens group, and FGr1 is a focal length of the front group of the furthest rear lens group. [2] Zoom lens (1) according to claim 1, wherein the rear group (L48 to L51 or L58 to L61) comprises a single lens (L51 or L61) with a negative meniscus shape at its most image-side position, the concave surface of which is directed towards the object side. [3] Zoom lens (1) according to one of claims 1 or 2, wherein the front group (L41 to L44 or L51 to L54) consists of three positive lenses and one negative lens. [4] Zoom lens (1) according to any one of claims 1 to 3, wherein the center group (Ois) consists of two negative lenses and one positive lens. [5] Zoom lens (1) according to any one of claims 1 to 4, wherein the object-side lens surface of the rear group (L48 to L51 or L58 to L61) is a convex surface and the rear group comprises a negative lens (L51 or L61) arranged at its image-side position and the cemented lens (L49, L50 or L59, L60) is arranged on the object side of the negative lens. [6] Zoom lens (1) according to claim 5, wherein the rear group (L48 to L51 or L58 to L61), in order starting from the object side, consists of a positive single lens (L48 or L58), the cement lens (L49, L50 or L59, L60) and a single lens (L51 or L61) with a negative meniscus shape, the concave surface of which is directed towards the object side. [7] Zoom lens according to any one of claims 1 to 6, wherein the first lens group (G1) consists, in order starting from the object side, of a negative lens (L11), a positive lens (L12), a positive lens (L13) and a positive lens (L14). [8] Zoom lens (1) according to any one of claims 1 to 7, wherein focusing from an object at infinity to a next object is effected by moving only the entire mp lens group (G3 or G4) or a part of the lenses forming the mp lens group along the optical axis (Z). [9] Zoom lens (1) according to any one of claims 1 to 8, wherein the following condition expression (3) is satisfied: 0.5 <FGr1 / FGr<1,3 [10] Zoom lens (1) according to any one of claims 1 to 9, wherein the following condition expression (4) is satisfied: 0.25 <FGr1 / Ft<0,60 where Ft is a focal length of the entire system when the zoom lens at the telephoto end is focused on an object at infinity. [11] Zoom lens (1) according to any one of claims 1 to 10, wherein the following condition expression (5) is satisfied: 0.12 <FGr3 / Ft<0,27 where Ft is a focal length of the entire system when the zoom lens at the telephoto end is focused on an object at infinity. [12] Zoom lens (1) according to any one of claims 1 to 11, wherein the following condition expression (6) is satisfied: 0.12 <BF / Ft<0,28 where BF is an equivalent air distance from the furthest rear lens group to the image plane (Sim) and Ft is a focal length of the entire system when the zoom lens at the telephoto end is focused on an object at infinity. [13] Zoom lens (1) according to any one of claims 1 to 12, wherein the following condition expression (7) is satisfied: 1.1 <TL / Ft<1,6 where TL is the total length of the optical system and Ft is the focal length of the entire system when the zoom lens at the telephoto end is focused on an object at infinity. [14] Zoom lens (1) according to any one of claims 1 to 13, comprising four lens groups which, starting from the object side in order, consist of the first lens group (G1), the second lens group (G2), the mp lens group (G3) and the furthest rear lens group (G4). [15] Imaging device comprising the zoom lens (1) according to any one of claims 1 to 14.

Images