Zoom lens and imaging device having the same

Abstract

A zoom lens that is small and has good optical characteristics, and an imaging device and an imaging system that have the same are provided. [Solution] The zoom lens L0 comprises, arranged in order from the object side to the image side, a first lens group L1 with negative refractive power, a second lens group L2 with positive refractive power, and a rear group LR including one or more lens groups. The rear group includes a focus lens group LP with positive refractive power that moves from the image side to the object side during focusing from infinity to a close distance. The focal length fLP of the focus lens group, the focal length fL1 of the first lens group, and the focal length fL2 of the second lens group satisfy a predetermined conditional expression.

Description

[Technical Field]

[0001] The present invention relates to a zoom lens suitable for imaging devices using solid-state imaging elements such as digital still cameras, digital video cameras, broadcast cameras, and surveillance cameras, or imaging devices such as cameras using silver halide photographic film. [Background technology]

[0002] Zoom lenses used in imaging devices are required to have a wide angle of view, be small in size, and have good optical characteristics. A known wide-angle zoom lens is a so-called negative-lead zoom lens, in which a lens group with negative refractive power is arranged closest to the object.

[0003] Negative-lead zoom lenses, in which a lens group with negative refractive power is positioned at the front, are characterized by the fact that it is relatively easy to achieve a wide angle of view and a long back focus. However, negative-lead zoom lenses tend to have an asymmetrical lens configuration with respect to the aperture stop, making it difficult to correct various aberrations. For example, it is difficult to suppress aberration fluctuations during focusing, making it very difficult to achieve high optical performance. In particular, with an inner focus system in which focusing is performed using a lens group located closer to the image than the first lens group L1, it is easy to make the focus lens group small and lightweight and to achieve high-speed focusing, but aberration fluctuations during focusing tend to increase. To achieve good optical performance while making the focus lens group small and lightweight, it is important to appropriately determine the power distribution of each lens group, including the focus lens group.

[0004] Patent Document 1 discloses a zoom lens comprising, arranged in order from the object side to the image side, a first lens group with negative refractive power, a second lens group with positive refractive power, a third lens group with negative refractive power, and a fourth lens group with positive refractive power. [Prior art documents] [Patent documents]

[0005] [Patent Document 1] Japanese Patent Application Publication No. 2019-040029 Summary of the Invention [Problem to be solved by the invention]

[0006] However, although the zoom lens described in Patent Document 1 achieves a compact focus lens group, the optical performance is insufficient.

[0007] The present invention provides a zoom lens that is small and has good optical characteristics, and an imaging device and an imaging system that include the same. [Means for solving the problem]

[0008] According to one aspect of the present invention, there is provided a zoom lens comprising, arranged in order from the object side to the image side, a first lens group having negative refractive power, a second lens group having positive refractive power, and a rear group including two or more lens groups, wherein the spacing between adjacent lens groups changes during zooming; the first lens group includes a first negative lens and a second negative lens arranged adjacent to each other in order from the object side to the image side, the image-side lens surface of the first negative lens being convex toward the object side; the rear group includes a focus lens group as the lens group having positive refractive power that moves from the image side to the object side during focusing from infinity to a close distance; and when the focal length of the focus lens group is fLP, the focal length of the first lens group is fL1, the focal length of the second lens group is fL2, the focal length of the first negative lens is fG1, and the focal length of the second negative lens is fG2, 1.20 <fLP / fL2<3.20 -3.00 <fL1 / fL2<-0.85 0 <fG1 / fG2<0.42 The present invention is characterized in that the following conditional expression is satisfied:

[0009] Other objects and features of the present invention will be described in the following embodiments. [Effects of the Invention]

[0010] According to the present invention, it is possible to provide a zoom lens that is small in size and has good optical characteristics, and an imaging device and an imaging system that include the same. [Brief explanation of the drawings]

[0011] [Figure 1] 1 is a lens cross-sectional view of a zoom lens according to a first embodiment. [Figure 2] 3A to 3C are aberration diagrams of the zoom lens of Example 1. [Figure 3] FIG. 10 is a cross-sectional view of a zoom lens according to a second embodiment. [Figure 4] 10A to 10C are aberration diagrams of the zoom lens of Example 2. [Figure 5] FIG. 10 is a cross-sectional view of a zoom lens according to a third embodiment. [Figure 6] 10A to 10C are aberration diagrams of the zoom lens of Example 3. [Figure 7] FIG. 10 is a cross-sectional view of a zoom lens according to a fourth embodiment. [Figure 8] 10A to 10C are aberration diagrams of the zoom lens of Example 4. [Figure 9] FIG. 10 is a cross-sectional view of a zoom lens according to a fifth embodiment. [Figure 10] 10A to 10C are aberration diagrams of the zoom lens of Example 5. [Figure 11] FIG. 10 is a cross-sectional view of a zoom lens according to a sixth embodiment. [Figure 12] 10A to 10C are aberration diagrams of the zoom lens of Example 6. [Figure 13] FIG. 1 is a schematic diagram of an imaging device. DETAILED DESCRIPTION OF THE INVENTION

[0012] DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS Hereinafter, embodiments of a zoom lens and an image pickup apparatus having the same according to the present invention will be described with reference to the accompanying drawings.

[0013] 1, 3, 5, 7, 9, and 11 are cross-sectional views of the zoom lens L0 of Examples 1 to 6, respectively, when focused on infinity at the wide-angle end. The zoom lens L0 of each Example is used in imaging devices such as digital video cameras, digital still cameras, broadcast cameras, silver halide film cameras, and surveillance cameras, as well as optical devices including interchangeable lenses.

[0014] In each lens cross-sectional view, the left side is the object side and the right side is the image side. The zoom lens L0 of each embodiment is configured with multiple lens groups. In this specification, a lens group refers to a component of the zoom lens L0 consisting of one lens or multiple lenses. A lens group may include an aperture stop or a flare-cutting stop. In the zoom lens L0 of each embodiment, the spacing between adjacent lens groups changes when zooming from the wide-angle end to the telephoto end.

[0015] In each lens cross-sectional view, Li represents the ith (i is a natural number) lens group included in the zoom lens L0, counting from the object side. SP is an aperture stop. FP is a flare-cut stop that cuts out unwanted light. IP is an image plane, on which the imaging surface of a solid-state imaging element (photoelectric conversion element) such as a CCD sensor or CMOS sensor is placed when the zoom lens L0 of each embodiment is used as the imaging optical system of a digital still camera or digital video camera. When the zoom lens L0 of each embodiment is used as the imaging optical system of a silver halide film camera, a photosensitive surface equivalent to the film surface is placed on the image plane IP.

[0016] The solid arrows in each lens cross-sectional diagram represent, in a simplified form, the movement locus of each lens group during zooming from the wide-angle end to the telephoto end. In this specification, the wide-angle end and the telephoto end refer to the zoom positions at which each lens group is located at the ends of its mechanically movable range along the optical axis. The dashed arrows in each lens cross-sectional diagram represent, in a simplified form, the movement locus of each lens group during focusing from infinity to the closest distance.

[0017] 2, 4, 6, 8, 10, and 12 are aberration diagrams of the zoom lens L0 of Examples 1 to 6, respectively. Each aberration diagram shows the state when focused at infinity, with (A) being the aberration diagram at the wide-angle end, (B) being the aberration diagram at the intermediate zoom position, and (C) being the aberration diagram at the telephoto end.

[0018] In the spherical aberration diagram, Fno is the F-number, and shows the amount of spherical aberration for the d-line (wavelength 587.6 nm) and g-line (wavelength 435.8 nm). In the astigmatism diagram, ΔS shows the amount of astigmatism on the sagittal image plane, and ΔM shows the amount of astigmatism on the meridional image plane. In the distortion diagram, the amount of distortion for the d-line is shown. In the chromatic aberration diagram, the amount of chromatic aberration for the g-line is shown. ω is the imaging half angle of view (°), which is the angle of view calculated by paraxial calculation.

[0019] Next, the characteristic configuration of the zoom lens L0 of each embodiment will be described.

[0020] The zoom lens L0 in each embodiment comprises, arranged in order from the object side to the image side, a first lens group L1 with negative refractive power, a second lens group L2 with positive refractive power, and a rear group LR including one or more lens groups. The rear group LR comprises all lens groups arranged closer to the image side than the second lens group L2. The zoom lens L0 is a zoom lens in which the spacing between adjacent lens groups changes during zooming. The rear group LR includes a lens group LP (focus lens group) with positive refractive power that moves from the image side to the object side during focusing from infinity to a close distance.

[0021] In the zoom lens L0 of each embodiment, the first lens unit L1 preferably includes a negative lens G1 (first negative lens) and a negative lens G2 (second negative lens) arranged in this order from the object side to the image side.

[0022] In the inner focus method, in which focusing is performed by a lens group located closer to the image than the first lens group L1, it is easy to make the focus lens group small and lightweight and to achieve high-speed focusing, but there is a tendency for aberration fluctuations to increase during focusing. In order to achieve good optical performance while making the focus lens group small and lightweight, it is important to appropriately set the power distribution of each lens group, including the focus lens group.

[0023] Therefore, in the zoom lens L0 of each embodiment, the focal length of each lens group is set appropriately. Specifically, the zoom lens L0 of each embodiment satisfies the following conditional expressions (1) and (2).

[0024] 1.20 <fLP / fL2<3.20 ···(1) -3.00 <fL1 / fL2<-0.85 ···(2) Here, fLP is the focal length of the lens group LP, fL1 is the focal length of the first lens group L1, and fL2 is the focal length of the second lens group L2.

[0025] Conditional expression (1) relates to the ratio of the focal length fLP of the lens unit LP to the focal length fL2 of the second lens unit L2. If the lower limit of conditional expression (1) is not met, the refractive power of the lens unit LP becomes strong, making it difficult to suppress fluctuations in various aberrations, including spherical aberration, that occur during focusing. On the other hand, if the upper limit of conditional expression (1) is exceeded, the refractive power of the lens unit LP becomes weak, making it necessary to move the lens unit LP for a longer distance during focusing.

[0026] Conditional expression (2) relates to the ratio of the focal length fL1 of the first lens group L1 to the focal length fL2 of the second lens group L2. If the lower limit of conditional expression (2) is not met, the refractive power of the first lens group L1 becomes too weak, making it difficult to reduce the size of the zoom lens. On the other hand, if the upper limit of conditional expression (2) is exceeded, the negative refractive power of the first lens group L1 becomes too strong, increasing off-axis aberrations such as coma and field curvature that occur in the first lens group L1 and making it difficult to adequately correct them.

[0027] With the above configuration, a zoom lens that is small in size and has good optical characteristics can be obtained.

[0028] It is more preferable that the numerical ranges of the above-mentioned conditional expressions (1) and (2) be set to the ranges of the following conditional expressions (1a) and (2a).

[0029] 1.30 <fLP / fL2<3.10 ···(1a) -2.50 <fL1 / fL2<-0.90 ···(2a) It is more preferable that the numerical ranges of the conditional expressions (1a) and (2a) satisfy the ranges of the following conditional expressions (1b) and (2b).

[0030] 1.40 <fLP / fL2<3.05 ···(1b) -2.00 <fL1 / fL2<-0.95 ···(2b) Here, the zoom lens L0 in each embodiment is designed to allow for the occurrence of distortion. Assuming the use of electronic aberration correction technology, which has been developed in recent years, this image processing technology can correct image distortion caused by distortion. Therefore, imaging optical systems incorporating these zoom lenses L0 have a design value for the amount of distortion that the zoom lens L0 possesses. Electronic images captured using these imaging optical systems are corrected by image processing in an arbitrary image processing unit (for example, a CPU attached to an imaging device such as a camera body) using the design value for the amount of distortion.

[0031] In a zoom lens that allows for distortion, a lens for correcting distortion is not required, making it easier to reduce the size and weight of the zoom lens. In particular, by making the effective imaging area (effective image circle diameter) of the image sensor at the wide-angle end smaller than the effective imaging area (effective image circle diameter) at the telephoto end and correcting the distortion, it contributes to reducing the diameter of the front lens.

[0032] In the zoom lens L0 of each embodiment, some lenses or some lens groups may be decentered (moved) in parallel in a direction including a component perpendicular to the optical axis (preferably in a direction perpendicular to the optical axis) during image blur correction, so that the zoom lens L0 has a function as an image stabilization optical system. Also, a parallel plate with substantially no refractive power, such as a low-pass filter or an infrared cut filter, may be disposed between the lens arranged closest to the image side and the imaging plane.

[0033] Next, conditions that are preferably satisfied in the zoom lens L0 of each embodiment will be described.

[0034] It is preferable that the zoom lens L0 of each embodiment satisfies one or more of the following conditional expressions (3) to (12).

[0035] 0.25 <DSPw / TLw<0.53 ···(3) 1.40 <ndG1<1.69 ···(4) 45<νdG1<95 (5) 1.40 <ndLPP<1.65 ···(6) 45<νdLPP<95 (7) 1.60 <ndL1P<2.10 ···(8) 15<νdL1P<45 (9) 0.50 <MLP / ML2<1.50 ···(10) 0 <fG1 / fG2<0.42 ···(11) -3.00<(G1R2+G1R1) / (G1R2-G1R1)<-0.10 ···(12) Here, DSPw is the distance on the optical axis from the aperture stop SP to the image plane IP at the wide-angle end. TLw is the total lens length of the zoom lens L0 at the wide-angle end. ndG1 is the refractive index of the negative lens G1 at the d-line, and νdG1 is the Abbe number of the negative lens G1 at the d-line. ndLPP is the refractive index of the positive lens LPP with the strongest refractive power (largest value of refractive power) among the positive lenses in the lens group LP at the d-line. Here, refractive power is expressed as the reciprocal of the focal length, and strong refractive power means that the value of the reciprocal of the focal length is large (small value of focal length). νdLPP is the Abbe number of the positive lens LPP with the strongest refractive power (largest value of refractive power) among the positive lenses in the lens group LP at the d-line. ndL1P is the refractive index of the positive lens L1P with the strongest refractive power (largest value of refractive power) among the positive lenses in the first lens group L1 at the d-line. νdL1P is the Abbe number for the d-line of the positive lens L1P with the strongest refractive power (largest refractive power value) among the positive lenses included in the first lens unit L1. MLP is the movement amount of the lens unit LP during zooming from the wide-angle end to the telephoto end when focused at infinity. The sign of the movement amount is negative when the lens unit LP is located closer to the object at the telephoto end than at the wide-angle end, and positive when it is located closer to the image. ML2 is the movement amount of the second lens unit L2 during zooming from the wide-angle end to the telephoto end. The sign of the movement amount is negative when the second lens unit L2 is located closer to the object at the telephoto end than at the wide-angle end, and positive when it is located closer to the image. fG1 is the focal length of the negative lens G1, and fG2 is the focal length of the negative lens G2. G1R2 is the radius of curvature of the image-side lens surface of the negative lens G1, and G1R1 is the radius of curvature of the object-side lens surface of the negative lens G1.

[0036] Conditional expression (3) relates to the ratio of the distance DSPw on the optical axis from the aperture stop SP to the image plane IP at the wide-angle end to the total lens length TLw at the wide-angle end. By positioning the aperture stop SP at an appropriate position, it becomes easy to reduce the diameter of the aperture stop SP while also reducing the size of the zoom lens L0. If the distance from the aperture stop SP to the image plane IP becomes too short, falling below the lower limit of conditional expression (3), the outer diameter of the lens positioned closer to the object than the aperture stop SP tends to increase. This makes it difficult to reduce the size of the zoom lens L0, which is undesirable. On the other hand, if the upper limit of conditional expression (3) is exceeded, the distance from the aperture stop SP to the image plane IP becomes too long, which causes the light beam diverging from the first lens unit L1 to enter the aperture stop SP without converging. This makes it difficult to reduce the diameter of the aperture stop SP, which makes it difficult to reduce the size of the zoom lens L0, which is undesirable.

[0037] Conditional expression (4) relates to the refractive index ndG1 of the negative lens G1. If the lower limit of conditional expression (4) is exceeded, the refractive index will be low, and therefore glass materials with low specific gravity will tend to be used. This is effective in reducing the weight of the zoom lens L0, but is undesirable because the refractive power will be weak and it will be difficult to reduce the size. If the upper limit of conditional expression (4) is exceeded, the specific gravity of the lens will be large, making it difficult to reduce the weight, and is undesirable.

[0038] Condition (5) relates to the Abbe number νdG1 of the negative lens G1 at the d-line. If the lower limit of condition (5) is exceeded, it becomes difficult to correct lateral chromatic aberration, which is undesirable. On the other hand, if the upper limit of condition (5) is exceeded, it becomes undesirable because lateral chromatic aberration is overcorrected.

[0039] Conditional expression (6) relates to the refractive index ndLPP at the d-line of the positive lens LPP, which has the strongest refractive power among the positive lenses included in the lens group LP. Below the lower limit of conditional expression (6), the refractive index of the positive lens LPP becomes too low, and the radius of curvature of the lens surface becomes too small to obtain the appropriate refractive power. This makes it difficult to correct various aberrations, including spherical aberration, which is undesirable. On the other hand, above the upper limit of conditional expression (6), the specific gravity of the positive lens LPP tends to increase, making it difficult to reduce the lens weight, which is undesirable.

[0040] Conditional expression (7) relates to the Abbe number νdLPP for the d-line of the positive lens LPP having the strongest refractive power among the positive lenses included in the lens group LP. If the lower limit of conditional expression (7) is not met, it becomes difficult to correct lateral chromatic aberration and longitudinal chromatic aberration, which is undesirable. If the upper limit of conditional expression (7) is exceeded, it becomes undesirable because the lateral chromatic aberration and longitudinal chromatic aberration are overcorrected.

[0041] Conditional expression (8) relates to the refractive index ndL1P at the d-line of the positive lens L1P, which has the strongest refractive power among the positive lenses included in the first lens group L1. If the upper limit of conditional expression (8) is exceeded and the refractive index of the positive lens L1P becomes high, the Petzval sum of the entire lens system becomes too small, making it difficult to correct curvature of field, which is undesirable. On the other hand, if the lower limit of conditional expression (8) is exceeded and the refractive index of the positive lens L1P becomes low, the Petzval sum of the entire lens system becomes too large, making it difficult to correct curvature of field, which is undesirable. Furthermore, in order to obtain an appropriate refractive power, the radius of curvature of the lens surface becomes small, making it difficult to correct off-axis aberrations such as coma, which is undesirable.

[0042] Conditional expression (9) relates to the Abbe number νdL1P for the d-line of the positive lens L1P with the strongest refractive power among the positive lenses included in the first lens group L1. If the lower limit of conditional expression (9) is not met, it becomes difficult to correct lateral chromatic aberration, which is undesirable. On the other hand, if the upper limit of conditional expression (9) is exceeded, it becomes difficult to correct lateral chromatic aberration and axial chromatic aberration, which is undesirable.

[0043] Conditional expression (10) relates to the ratio between the amount of movement MLP of the lens unit LP during zooming from the wide-angle end to the telephoto end when focused at infinity, and the amount of movement ML2 of the second lens unit L2 during zooming from the wide-angle end to the telephoto end. If the lower limit of conditional expression (10) is exceeded, the amount of movement of the second lens unit L2 increases, undesirably increasing the overall lens length at the wide-angle end. On the other hand, if the upper limit of conditional expression (10) is exceeded, the amount of movement of the second lens unit L2 decreases, and the refractive power of the second lens unit L2 becomes too strong to achieve the desired zoom ratio. This makes it difficult to suppress fluctuations in various aberrations, including spherical aberration, during zooming, undesirably.

[0044] Conditional expression (11) relates to the ratio of the focal length fG1 of the negative lens G1 to the focal length fG2 of the negative lens G2. If the lower limit of conditional expression (11) is exceeded, one of the negative lens G1 or the negative lens G2 will be a positive lens, making it difficult to achieve a wide angle, which is undesirable. Note that if the absolute value of the focal length of the negative lens G1 is excessively small compared to the focal length of the negative lens G2, it may be difficult to achieve both a wide angle and high performance. Therefore, as described below, it is also preferable to set the lower limit of conditional expression (11) to a value greater than 0. If the upper limit of conditional expression (11) is exceeded, the refractive power of the negative lens G1 will be too weak, making it difficult to reduce the size of the zoom lens L0, which is undesirable. Alternatively, the refractive power of the negative lens G2 will be too strong, making it difficult to correct off-axis aberrations such as field curvature, which is undesirable.

[0045] Conditional expression (12) relates to the shape of the negative lens G1. If the lower limit of conditional expression (12) is exceeded, the negative lens G1 will have negative refractive power, resulting in a meniscus shape convex toward the object side and a shape with weak refractive power. In this case, the negative lens G1 will not have sufficient refractive power, and the refractive power of the lens on the image side of the negative lens G1 will be strong, making it difficult to correct off-axis aberrations such as field curvature, which is undesirable. On the other hand, if the upper limit of conditional expression (12) is exceeded, the negative lens G1 will have a biconcave shape or a meniscus shape convex toward the image side, and the radius of curvature of the object-side surface of the negative lens G1 will be small. In this case, the occurrence of off-axis aberrations such as field curvature at the object-side surface of the negative lens G1 will increase, making correction difficult, which is undesirable. Alternatively, the negative lens G1 will have a shape with weak refractive power, making it difficult to correct off-axis aberrations such as field curvature, which is undesirable.

[0046] It is more preferable that the numerical ranges of the conditional expressions (3) to (12) be the numerical ranges of the following conditional expressions (3a) to (12a).

[0047] 0.28 <DSPw / TLw<0.51 ···(3a) 1.50 <ndG1<1.67 ···(4a) 50<νdG1<85 (5a) 1.45 <ndLPP<1.63 ···(6a) 55<νdLPP<90 (7a) 1.65 <ndL1P<2.05 ···(8a) 18<νdL1P<40 (9a) 0.60 <MLP / ML2<1.40 ···(10a) 0.05 <fG1 / fG2<0.41 ···(11a) -2.50<(G1R2+G1R1) / (G1R2-G1R1)<-0.30 (12a) It is more preferable that the numerical ranges of the conditional expressions (3) to (12) be the numerical ranges of the following conditional expressions (3b) to (12b).

[0048] 0.30 <DSPw / TLw<0.50 ···(3b) 1.55 <ndG1<1.65 ···(4b) 55<νdG1<75 (5b) 1.48 <ndLPP<1.61 ···(6b) 65<νdLPP<85 (7b) 1.68 <ndL1P<2.01 ···(8b) 20<νdL1P<35 (9b) 0.70 <MLP / ML2<1.30 ···(10b) 0.09 <fG1 / fG2<0.40 ···(11b) -2.00<(G1R2+G1R1) / (G1R2-G1R1)<-0.50 (12b) Next, the configuration that is preferably satisfied in the zoom lens L0 of each embodiment will be described.

[0049] The first lens group L1 preferably consists of a negative lens G1, a negative lens G2, and a positive lens L1P arranged in that order from the object side to the image side, which makes it easier to correct off-axis aberrations such as field curvature at the wide-angle end.

[0050] At least one of the object-side and image-side lens surfaces of the negative lens G2 preferably has an aspherical shape, which facilitates correction of off-axis aberrations such as coma and field curvature at the wide-angle end.

[0051] The negative lens G2 is preferably made of a resin material, which makes it easier to reduce the weight of the zoom lens L0 by using a resin material for the negative lens G2, which tends to have a large outer diameter.

[0052] It is preferable that the negative lens G1 and the negative lens G2 have an air gap on the optical axis, which makes it easier to correct off-axis aberrations such as coma and curvature of field.

[0053] When performing image blur correction, it is preferable to decenter (move) the second lens group L2 in a direction that includes a component perpendicular to the optical axis (preferably, in a direction perpendicular to the optical axis). By using the second lens group L2, in which the light beam converges, as the lens group for image blur correction, it becomes easy to make the lens group for image blur correction compact.

[0054] The number of lenses in the second lens group L2 is preferably three or less, which makes it easier to reduce the weight of the zoom lens L0.

[0055] It is preferable that the second lens group L2 includes an aperture stop SP, and that the aperture stop SP be located closest to the image side of the second lens group L2. Since the light beam converges on the image side of the second lens group L2, it is easy to make the aperture stop SP compact.

[0056] It is preferable to focus from infinity to close distances by moving the lens unit LP with positive refractive power included in the rear group LR from the image side to the object side. Axial rays converge on the image side of the second lens unit L2. This makes it easy to suppress fluctuations in various aberrations, including spherical aberration, during focusing.

[0057] The lens group LP preferably comprises one positive lens element having a meniscus shape with its concave surface facing the object side. Here, the one lens element is a single lens or a cemented lens. By making the lens surface facing the object side of the lens group LP concave, the angle of incidence of off-axial rays with respect to the lens surface can be made gentler, making it easier to suppress fluctuations in off-axial aberrations such as field curvature during focusing.

[0058] Next, the zoom lens L0 of each embodiment will be described in detail.

[0059] The zoom lens L0 of Examples 1 and 2 comprises a first lens unit L1, a second lens unit L2, a third lens unit L3 with positive refractive power, and a fourth lens unit L4 with negative refractive power. In the zoom lens L0 of Examples 1 and 2, the third lens unit L3 and the fourth lens unit L4 correspond to the rear group LR. During zooming from the wide-angle end to the telephoto end, the first lens unit L1 moves along a convex locus toward the image side, while the second lens unit L2, the third lens unit L3, and the fourth lens unit L4 move monotonically toward the object side. Note that in the zoom lens L0 of Examples 1 and 2, the second lens unit L2 and the fourth lens unit L4 move integrally (along the same locus) during zooming. The third lens unit L3 corresponds to the lens unit LP with positive refractive power, and focusing from an object point at infinity to an object point at a close distance is performed by moving the third lens unit L3 along the optical axis.

[0060] The zoom lens L0 of Example 3 comprises a first lens group L1, a second lens group L2, a third lens group L3 with positive refractive power, and a fourth lens group L4 with positive refractive power. In the zoom lens L0 of Example 3, the third lens group L3 and the fourth lens group L4 correspond to the rear group LR. During zooming from the wide-angle end to the telephoto end, the first lens group L1 moves along a convex locus toward the image side, while the second lens group L2, the third lens group L3, and the fourth lens group L4 move monotonically toward the object side. Note that in the zoom lens L0 of Example 3, the second lens group L2 and the fourth lens group L4 move integrally (along the same locus) during zooming. The third lens group L3 corresponds to the lens group LP with positive refractive power, and focusing from an object point at infinity to an object point at a close distance is performed by moving the third lens group L3 along the optical axis.

[0061] The zoom lens L0 of Example 4 is composed of a first lens unit L1, a second lens unit L2, a third lens unit L3 with positive refractive power, a fourth lens unit L4 with negative refractive power, and a fifth lens unit L5 with positive refractive power. In the zoom lens L0 of Example 4, the third lens unit L3, the fourth lens unit L4, and the fifth lens unit L5 correspond to the rear group LR. During zooming from the wide-angle end to the telephoto end, the first lens unit L1 moves along a convex locus toward the image side, the second lens unit L2, the third lens unit L3, and the fourth lens unit L4 move monotonically toward the object side, and the fifth lens unit L5 moves monotonically toward the image side. Note that in the zoom lens L0 of Example 4, the second lens unit L2 and the fourth lens unit L4 move together (along the same locus) during zooming. The third lens group L3 corresponds to the lens group LP having a positive refractive power, and by moving the third lens group L3 along the optical axis, focusing is performed from an object point at infinity to an object point at a close distance.

[0062] The zoom lens L0 of Example 5 comprises a first lens unit L1, a second lens unit L2, a third lens unit L3 with negative refractive power, a fourth lens unit L4 with positive refractive power, and a fifth lens unit L5 with negative refractive power. In the zoom lens L0 of Example 5, the third lens unit L3, the fourth lens unit L4, and the fifth lens unit L5 correspond to the rear group LR. During zooming from the wide-angle end to the telephoto end, the first lens unit L1 moves along a convex locus toward the image side, while the second lens unit L2, the third lens unit L3, the fourth lens unit L4, and the fifth lens unit L5 move monotonically toward the object side. Note that in the zoom lens L0 of Example 5, the second lens unit L2 and the fifth lens unit L5 move together (along the same locus) during zooming. The fourth lens group L4 corresponds to the lens group LP having a positive refractive power, and by moving the fourth lens group L4 along the optical axis, focusing is performed from an object point at infinity to an object point at a close distance.

[0063] The zoom lens L0 of Example 6 is composed of a first lens unit L1, a second lens unit L2, a third lens unit L3 with negative refractive power, a fourth lens unit L4 with positive refractive power, a fifth lens unit L5 with negative refractive power, and a sixth lens unit L6 with positive refractive power. In the zoom lens L0 of Example 6, the third lens unit L3, the fourth lens unit L4, the fifth lens unit L5, and the sixth lens unit L6 correspond to the rear group LR. During zooming from the wide-angle end to the telephoto end, the first lens unit L1 moves along a convex locus toward the image side, while the second lens unit L2, the third lens unit L3, the fourth lens unit L4, the fifth lens unit L5, and the sixth lens unit L6 move monotonically toward the object side. Note that in the zoom lens L0 of Example 6, the second lens unit L2 and the fifth lens unit L5 move together (along the same locus) during zooming. The fourth lens group L4 corresponds to the lens group LP having a positive refractive power, and by moving the fourth lens group L4 along the optical axis, focusing is performed from an object point at infinity to an object point at a close distance.

[0064] Numerical Examples 1 to 6 corresponding to Examples 1 to 6, respectively, are shown below.

[0065] In the surface data of each numerical example, r represents the radius of curvature of each optical surface, and d (mm) represents the axial spacing (distance on the optical axis) between the mth surface and the (m+1)th surface. Here, m is the surface number counted from the light incident side. Furthermore, nd represents the refractive index of each optical element with respect to the d-line, and vd represents the Abbe number of the optical element. Note that the Abbe number vd of a certain material is given by the following equation, where Nd, NF, and NC are the refractive indices at the d-line (587.6 nm), F-line (486.1 nm), and C-line (656.3 nm) of the Fraunhofer lines: νd=(Nd-1) / (NF-NC) It is expressed as:

[0066] In each numerical example, d, focal length (mm), F-number, and half angle of view (°) are all values ​​when the zoom lens L0 of each example is focused on an object at infinity. "Back focus" is the distance on the optical axis from the final lens surface (the lens surface closest to the image) to the paraxial image plane, expressed as an air-equivalent length. "Total lens length" is the distance on the optical axis from the forefront lens surface (the lens surface closest to the object) of the zoom lens L0 to the final surface plus the back focus. "Lens group" is not limited to cases where it is composed of multiple lenses, but also includes cases where it is composed of a single lens.

[0067] If the optical surface is aspherical, an asterisk (*) is added to the right of the surface number. The aspherical shape is expressed as follows: X is the displacement from the vertex of the surface in the optical axis direction, h is the height from the optical axis in the direction perpendicular to the optical axis, R is the paraxial radius of curvature, K is the conic constant, and A4, A6, A8, A10, and A12 are the aspherical coefficients of each order. X=(h 2 / R) / [1+[1-(1+K)(h / R) 2 ] 1 / 2 ]+A4×h 4 +A6×h 6 +A8×h 8 +A10×h 10 +A12×h 12 In addition, "e±XX" in each aspherical coefficient is "×10± XX " means. [Numerical Example 1] Unit: mm Surface Data Surface number rd nd νd 1 238.756 1.40 1.63854 55.4 2 18.479 7.21 3* 994.673 3.70 1.53110 55.9 4 56.399 0.30 5 28.004 3.60 1.69895 30.1 6 65.231 (variable) 7 21.644 3.00 1.90366 31.3 8 -709.102 2.60 9 -102.707 0.70 1.84666 23.9 10 16.164 0.37 11 26.583 2.05 1.77250 49.6 12 -76.939 2.00 13 (Aperture) ∞ 6.15 14 ∞ (variable) 15 -65.961 2.95 1.48749 70.2 16 -21.205 (variable) 17* -90.404 3.50 1.53110 55.9 18* -1111.779 (variable) Image plane ∞ Aspheric data 3rd page K = 0.00000e+000 A 4= 2.06228e-006 A 6=-3.09541e-009 A 8= 7.24904e-011 A10=-3.07809e-013 A12= 9.19241e-016 Page 17 K = 0.00000e+000 A 4=-1.01775e-004 A 6= 1.71677e-007 A 8= 1.83977e-010 A10=-1.16025e-011 A12= 2.80092e-014 Side 18 K = 0.00000e+000 A 4=-9.00719e-005 A 6= 2.07355e-007 A 8=-1.21619e-010 A10=-4.95038e-012 A12= 1.35424e-014 Various data Zoom ratio 1.96 Wide-angle Mid-range Telephoto Focal length 24.71 35.01 48.53 F-number 4.63 5.66 6.48 Half angle of view (°) 36.23 29.55 23.08 Image height 18.10 19.85 20.68 Lens length 105.60 98.52 99.03 BF 16.94 25.84 37.19 d 6 27.85 11.87 1.02 d14 10.04 10.38 10.30 d16 11.24 10.91 10.98 d18 16.94 25.84 37.19 Zoom lens group data Group starting plane focal length 1 1 -40.14 2 7 39.51 3 15 62.75 4 17 -185.51 [Numerical Example 2] Unit: mm Surface Data Surface number rd nd νd 1 194.836 1.40 1.63854 55.4 2 19.216 7.45 3* 97.731 3.30 1.53110 55.9 4 50.481 0.15 5 25.378 3.36 1.74077 27.8 6 40.484 (variable) 7 28.994 1.78 1.95375 32.3 8 -2837.037 4.32 9 -36.870 0.55 1.80810 22.8 10 26.363 0.35 11 61.033 1.82 1.85150 40.8 12 -30.900 2.06 13 (Aperture) ∞ (Variable) 14 ∞ 9.45 15 -87.219 2.77 1.48749 70.2 16 -22.880 (variable) 17* -140.744 3.55 1.53110 55.9 18* 244.765 (variable) Image plane ∞ Aspheric data 3rd page K = 0.00000e+000 A 4= 1.74257e-006 A 6=-2.46696e-009 A 8= 7.75729e-011 A10=-3.31377e-013 A12= 8.09051e-016 Page 17 K = 0.00000e+000 A 4=-8.76708e-005 A 6= 1.10417e-007 A 8= 2.08926e-009 A10=-3.00779e-011 A12= 1.05365e-013 Side 18 K = 0.00000e+000 A 4=-8.05410e-005 A 6= 2.07802e-007 A 8= 2.03128e-010 A10=-8.66422e-012 A12= 2.90115e-014 Various data Zoom ratio 1.96 Wide-angle Mid-range Telephoto Focal length 24.72 36.55 48.52 F-number 4.64 5.88 6.49 Half angle of view (°) 36.09 28.56 23.01 Image height 18.02 19.90 20.61 Lens length 108.53 98.64 98.06 BF 16.96 26.55 36.14 d 6 30.74 11.26 1.09 d13 7.26 7.81 8.06 d16 11.25 10.70 10.44 d18 16.96 26.55 36.14 Zoom lens group data Group starting plane focal length 1 1 -44.09 2 7 41.43 3 14 62.74 4 17 -167.72 [Numerical Example 3] Unit: mm Surface Data Surface number rd nd νd 1 232.845 1.40 1.62299 58.2 2 19.941 7.96 3* 111.062 3.30 1.53110 55.9 4 51.120 0.15 5 27.285 3.28 1.85026 32.3 6 42.225 (variable) 7 21.725 3.96 1.95375 32.3 8 1131.357 2.85 9 -46.823 0.55 1.80810 22.8 10 20.233 0.51 11 60.580 1.70 1.80400 46.5 12 -36.758 1.68 13 (Aperture) ∞ (Variable) 14 ∞ 5.20 15 -49.571 2.22 1.49700 81.5 16 -27.201 (variable) 17* 39.782 3.43 1.53110 55.9 18* 50.673 (variable) Image plane ∞ Aspheric data 3rd page K = 0.00000e+000 A 4= 1.84216e-006 A 6= 8.01311e-010 A 8= 5.12283e-011 A10=-2.30863e-013 A12= 5.59343e-016 Page 17 K = 0.00000e+000 A 4=-4.36850e-005 A 6=-1.04709e-007 A 8= 1.10943e-009 A10=-6.81115e-012 A12= 1.19305e-014 Side 18 K = 0.00000e+000 A 4=-4.39901e-005 A 6=-9.00326e-008 A 8= 9.46107e-010 A10=-5.28840e-012 A12= 9.00245e-015 Various data Zoom ratio 1.96 Wide-angle Mid-range Telephoto Focal length 24.71 36.32 48.52 F-number 4.64 5.88 6.49 Half angle of view (°) 36.10 28.72 23.02 Image height 18.02 19.90 20.62 Lens length 111.00 99.87 98.01 BF 16.96 26.97 36.98 d 6 34.02 12.88 1.01 d13 14.34 17.31 17.82 d16 7.48 4.50 3.99 d18 16.96 26.97 36.98 Zoom lens group data Group starting plane focal length 1 1 -46.24 2 7 38.99 3 14 117.40 4 17 314.18 [Numerical Example 4] Unit: mm Surface Data Surface number rd nd νd 1 -1120.940 1.40 1.63854 55.4 2 29.481 9.39 3* -105.871 3.30 1.53110 55.9 4* -390.341 0.15 5 37.169 5.61 2.00100 29.1 6 55.239 (variable) 7 22.578 3.84 1.85150 40.8 8 -4398.814 3.78 9 -49.047 3.04 1.76182 26.5 10 19.940 0.38 11 38.988 1.70 1.77250 49.6 12 -50.780 1.49 13 (Aperture) ∞ (Variable) 14 ∞ 8.31 15 -60.430 2.44 1.53775 74.7 16 -28.373 (variable) 17* 27.547 3.42 1.53110 55.9 18* 19.381 (variable) 19 -476.759 2.53 1.98612 16.5 20 -139.384 (variable) Image plane ∞ Aspheric data 3rd page K = 0.00000e+000 A 4= 1.73506e-005 A 6=-5.81504e-008 A 8= 2.33643e-010 A10=-4.73065e-013 A12= 3.72284e-016 Side 4 K = 2.78976e+002 A 4= 1.77155e-005 A 6=-5.73090e-008 A 8= 2.47146e-010 A10=-5.30598e-013 A12= 4.44306e-016 Page 17 K = 0.00000e+000 A 4=-1.15240e-004 A 6= 1.08980e-007 A 8= 1.09284e-009 A10=-9.51817e-012 A12= 2.49887e-014 Side 18 K = 0.00000e+000 A 4=-1.42130e-004 A 6= 2.49994e-007 A 8= 5.94173e-011 A10=-4.17813e-012 A12= 1.06545e-014 Various data Zoom ratio 2.07 Wide-angle Mid-range Telephoto Focal length 26.52 40.09 55.00 F-number 4.63 5.88 6.49 Half angle of view (°) 34.19 26.40 20.54 Image height 18.02 19.90 20.61 Lens total length 130.02 109.61 101.49 BF 11:57 11:28 11:00 d 6 47.80 18.28 1.05 d13 12.86 15.19 14.62 d16 4.53 2.19 2.76 d18 2.50 11.89 21.29 d20 11.57 11.28 11.00 Zoom lens group data Group starting plane focal length 1 1 -66.85 2 7 42.89 3 14 96.88 4 17 -144.01 5 19 199.00 [Numerical Example 5] Unit: mm Surface Data Surface number rd nd νd 1 80.208 1.40 1.63854 55.4 2 19.361 14.61 3* -164.348 2.80 1.53110 55.9 4* 253.136 0.15 5 38.801 2.51 1.92286 20.9 6 55.307 (variable) 7 21.105 4.44 1.91082 35.3 8 -157.113 0.10 9 -95.832 4.01 1.85451 25.2 10 15.464 0.27 11 20.249 2.55 1.63930 44.9 12 -54.619 1.98 13 (Aperture) ∞ (Variable) 14 -20.018 0.80 1.83481 42.7 15 -24.304 (variable) 16∞5.38 17 -79.509 2.82 1.49700 81.5 18 -23.407 (variable) 19* 106.844 3.57 1.53110 55.9 20* 35.485 (variable) Image plane ∞ Aspheric data 3rd page K = 0.00000e+000 A 4= 8.19088e-006 A 6=-4.23962e-008 A 8= 4.87158e-011 A10=2.63400e-013 A12=-6.28278e-016 Side 4 K =-1.79037e+002 A 4= 6.17666e-006 A 6=-5.09905e-008 A 8= 3.25197e-011 A10=3.67841e-013 A12=-9.82139e-016 Page 19 K = 0.00000e+000 A 4=-1.33629e-004 A 6= 9.73781e-008 A 8= 1.70352e-009 A10=-1.81236e-011 A12= 4.81540e-014 Page 20 K = 0.00000e+000 A 4=-1.31273e-004 A 6= 3.10386e-007 A 8= 7.12932e-012 A10=-5.06314e-012 A12= 1.39234e-014 Various data Zoom ratio 2.35 Wide-angle Mid-range Telephoto Focal length 20.61 33.70 48.50 F-number 4.63 5.88 6.49 Half angle of view (°) 41.17 30.56 23.03 Image height 18.02 19.90 20.61 Lens total length 120.00 104.38 100.66 BF 10.49 20.91 31.34 d 6 41.21 15.16 1.01 d13 4.86 6.13 7.40 d15 6.56 8.20 6.82 d18 9.48 6.58 6.69 d20 10.49 20.91 31.34 Zoom lens group data Group starting plane focal length 1 1 -45.32 2 7 32.92 3 14 -148.57 4 16 65.65 5 19 -101.81 [Numerical Example 6] Unit: mm Surface Data Surface number rd nd νd 1 91.050 1.40 1.63854 55.4 2 22.276 17.49 3* -59.262 2.80 1.53110 55.9 4* -858.745 0.15 5 46.234 3.30 1.92286 20.9 6 79.048 (variable) 7 21.043 4.64 1.80400 46.5 8 172.624 2.15 9 -5060.863 4.00 1.73037 32.2 10 13.782 0.37 11 17.389 4.12 1.75500 52.3 12 -278.333 1.71 13 (Aperture) ∞ (Variable) 14* -66.256 1.20 1.82165 24.0 15 -282.440 3.65 16 ∞ (variable) 17 -129.496 4.64 1.59522 67.7 18 -13.532 1.00 1.72916 54.7 19 -22.824 (variable) 20* 110.948 2.98 1.53110 55.9 21* 29.174 (variable) 22 154.476 2.41 1.98612 16.5 23 -14900.415 (variable) Image plane ∞ Aspheric data 3rd page K = 0.00000e+000 A 4= 2.47198e-005 A 6=-8.08847e-008 A 8= 1.65476e-010 A10=-1.37297e-013 A12= 3.16753e-017 Side 4 K =-8.61713e+003 A 4= 1.91654e-005 A 6=-6.74993e-008 A 8= 7.58767e-011 A10= 1.07307e-013 A12=-2.66741e-016 Side 14 K = 0.00000e+000 A 4=-9.45333e-006 A 6= 1.17313e-007 A 8=-6.37183e-012 A10= 2.95045e-011 A12= 0.00000e+000 Page 20 K = 0.00000e+000 A 4=-1.23685e-004 A 6= 4.03138e-007 A 8= 6.98371e-010 A10=-1.74137e-011 A12= 5.43473e-014 Page 21 K = 0.00000e+000 A 4=-1.34776e-004 A 6= 5.78897e-007 A 8=-1.36238e-009 A10=-2.66916e-012 A12= 1.50537e-014 Various data Zoom ratio 2.84 Wide-angle Mid-range Telephoto Focal length 20.61 39.47 58.50 F-number 4.64 5.88 6.49 Half angle of view (°) 41.17 26.75 19.41 Image height 18.02 19.90 20.61 Lens total length 135.00 120.11 125.50 BF 10.49 11.09 11.70 d 6 46.04 13.39 1.02 d13 2.30 4.06 5.83 d16 7.15 9.97 10.76 d19 9.71 5.12 2.57 d21 1.30 18.46 35.61 d23 10.49 11.09 11.70 Zoom lens group data Group starting plane focal length 1 1 -47.50 2 7 34.88 3 14 -105.62 4 17 55.50 5 20 -75.48 6 22 155.06 The various values ​​in each numerical example are summarized in Table 1 below.

[0068] [Table 1]

[0069] [Imaging device] Next, an embodiment of a digital camera (image capture device) that uses the zoom lens L0 of the present invention as an image capture optical system will be described with reference to Fig. 13. Fig. 13 is a schematic diagram of an image capture device (digital still camera) 10 of this embodiment. The image capture device 10 includes a camera body 13, a zoom lens 11 similar to any of the above-described embodiments 1 to 6, and a light receiving element (image capture element) 12 that is built into the camera body 13 and photoelectrically converts an optical image formed by the zoom lens 11. The camera body 13 may be a so-called single-lens reflex camera that has a quick-turn mirror, or a so-called mirrorless camera that does not have a quick-turn mirror.

[0070] The imaging device 10 of this embodiment has a zoom lens 11 that is small and has good optical characteristics, and therefore can obtain high-quality images.

[0071] It should be noted that an imaging element such as a CCD or CMOS sensor can be used as the light receiving element 12. In this case, various aberrations such as distortion and chromatic aberration of the image acquired by the light receiving element 12 can be electrically corrected to improve the image quality of the output image.

[0072] The zoom lens L0 of each of the above-described embodiments can be applied not only to the digital still camera shown in FIG. 13, but also to various optical devices such as silver halide film cameras, video cameras, and telescopes. [Imaging system] An imaging system (surveillance camera system) may be configured that includes the zoom lens L0 of each embodiment and a control unit that controls the zoom lens L0. In this case, the control unit can control the zoom lens L0 so that each lens group moves as described above during zooming, focusing, and image blur correction. In this case, the control unit does not need to be configured integrally with the zoom lens L0; the control unit may be configured separately from the zoom lens L0. For example, a control unit (control device) located far from the drive units that drive each lens of the zoom lens L0 may include a transmission unit that sends control signals (commands) to control the zoom lens L0. Such a control unit allows the zoom lens L0 to be remotely controlled.

[0073] Alternatively, the control unit may be provided with an operation unit such as a controller or buttons for remotely operating the zoom lens L0, thereby controlling the zoom lens L0 in response to user input to the operation unit. For example, the operation unit may be provided with a zoom-in button and a zoom-out button. In this case, the control unit may be configured to send a signal to a drive unit for the zoom lens L0 so that the magnification of the zoom lens L0 increases when the user presses the zoom-in button, and decreases when the user presses the zoom-out button.

[0074] The imaging system may also have a display unit such as a liquid crystal panel that displays information (movement state) related to the zoom of the zoom lens L0. Information related to the zoom of the zoom lens L0 may be, for example, the zoom magnification (zoom state) or the movement amount (movement state) of each lens group. In this case, the user can remotely operate the zoom lens L0 via an operation unit while viewing the information related to the zoom of the zoom lens L0 displayed on the display unit. In this case, the display unit and operation unit may be integrated by using, for example, a touch panel.

[0075] Although the preferred embodiments and examples of the present invention have been described above, the present invention is not limited to these embodiments and examples, and various combinations, modifications, and changes are possible within the scope of the gist of the present invention. [Explanation of symbols]

[0076] L0 zoom lens L1 First lens group L2 Second lens group LR rear group LP focus lens group

Claims

1. A zoom lens comprising, arranged in order from the object side to the image side, a first lens group having negative refractive power, a second lens group having positive refractive power, and a rear group including two or more lens groups, wherein the spacing between adjacent lens groups changes during zooming, the first lens group includes a first negative lens and a second negative lens arranged adjacent to each other in order from the object side to the image side, an image-side lens surface of the first negative lens is convex toward the object side, the rear group includes a focus lens group, which is the lens group having positive refractive power and moves from the image side to the object side during focusing from infinity to a close distance, When the focal length of the focus lens group is fLP, the focal length of the first lens group is fL1, the focal length of the second lens group is fL2, the focal length of the first negative lens is fG1, and the focal length of the second negative lens is fG2, 1.20<fLP / fL2<3.20 -3.00<fL1 / fL2<-0.85 0<fG1 / fG2<0.42 A zoom lens characterized by satisfying the following conditional expressions:

2. the second lens group includes an aperture stop; When the distance on the optical axis from the aperture stop to the image plane at the wide-angle end is DSPw and the total lens length of the zoom lens at the wide-angle end is TLw, 0.25<DSPw / TLw<0.53 2. The zoom lens according to claim 1, wherein the following condition is satisfied:

3. When the refractive index of the material of the first negative lens is ndG1, 1.40<ndG1<1.69 3. The zoom lens according to claim 1, wherein the following condition is satisfied:

4. When the Abbe number of the material of the first negative lens is νdG1, 45<νdG1<95 4. The zoom lens according to claim 1, wherein the following condition is satisfied:

5. the focus lens group includes one or more positive lenses, When the refractive index of the material of the positive lens having the largest refractive power among the positive lenses included in the focus lens group is ndLPP, 1.40<ndLPP<1.65 5. The zoom lens according to claim 1, wherein the following condition is satisfied:

6. the focus lens group includes one or more positive lenses, When the Abbe number of the material of the positive lens having the largest refractive power among the positive lenses included in the focus lens group is νdLPP, 45<νdLPP<95 6. The zoom lens according to claim 1, wherein the following condition is satisfied:

7. the first lens group includes one or more positive lenses; When the refractive index of the material of the positive lens having the largest refractive power among the positive lenses included in the first lens group is ndL1P, 1.60<ndL1P<2.10 7. The zoom lens according to claim 1, wherein the following condition is satisfied:

8. the first lens group includes one or more positive lenses; When the Abbe number of the material of the positive lens having the largest refractive power among the positive lenses included in the first lens group is νdL1P, 15<νdL1P<45 8. The zoom lens according to claim 1, wherein the following condition is satisfied:

9. 9. The zoom lens according to claim 1, wherein the first negative lens and the second negative lens have an air gap on the optical axis.

10. When the focus lens unit is focused at infinity, the amount of movement of the focus lens unit during zooming from the wide-angle end to the telephoto end is MLP, and the amount of movement of the second lens unit during zooming from the wide-angle end to the telephoto end is ML2. 0.50<MLP / ML2<1.50 10. The zoom lens according to claim 1, wherein the following condition is satisfied:

11. When the radius of curvature of the image-side lens surface of the first negative lens is G1R2 and the radius of curvature of the object-side lens surface of the first negative lens is G1R1, -3.00<(G1R2+G1R1) / (G1R2-G1R1)<-0.10 11. The zoom lens according to claim 1, wherein the following condition is satisfied:

12. 12. The zoom lens according to claim 1, wherein the first lens group consists of the first negative lens, the second negative lens, and a positive lens, arranged in this order from the object side to the image side.

13. 13. The zoom lens according to claim 1, wherein the second negative lens is made of a resin material.

14. 14. The zoom lens according to claim 1, wherein at least one of the object-side and image-side lens surfaces of the second negative lens has an aspherical shape.

15. the second lens group includes an aperture stop; 15. The zoom lens according to claim 1, wherein the aperture stop is disposed closest to the image side of the second lens group.

16. 16. The zoom lens according to claim 1, wherein the second lens group is composed of three or less lenses.

17. 17. The zoom lens according to claim 1, wherein the focus lens group is composed of one positive lens element having a meniscus shape with a concave surface facing the object side.

18. 18. The zoom lens according to claim 1, wherein the second lens group moves in a direction including a component perpendicular to the optical axis during image blur correction.

19. the rear group includes at least one aspherical lens; 19. The zoom lens according to claim 1, wherein at least one of the object-side lens surface and the image-side lens surface of the aspherical lens is an aspherical surface having an inflection point.

20. 20. The zoom lens according to claim 1, wherein the first lens group moves along a locus that is convex toward the image side during zooming from the wide-angle end to the telephoto end.

21. 21. The zoom lens according to claim 1, wherein the rear group comprises, arranged in order from the object side to the image side, a third lens group having a positive refractive power and a fourth lens group having a negative refractive power.

22. 21. The zoom lens according to claim 1, wherein the rear group comprises, in order from the object side to the image side, a third lens group having a positive refractive power and a fourth lens group having a positive refractive power.

23. 21. The zoom lens according to claim 1, wherein the rear group consists of, arranged in order from the object side to the image side, a third lens group having a positive refractive power, a fourth lens group having a negative refractive power, and a fifth lens group having a positive refractive power.

24. 21. The zoom lens according to claim 1, wherein the rear group consists of, arranged in order from the object side to the image side, a third lens group having negative refractive power, a fourth lens group having positive refractive power, and a fifth lens group having negative refractive power.

25. 21. The zoom lens according to claim 1, wherein the rear group consists of, arranged in order from the object side to the image side, a third lens group having negative refractive power, a fourth lens group having positive refractive power, a fifth lens group having negative refractive power, and a sixth lens group having positive refractive power.

26. 26. An imaging device comprising: the zoom lens according to claim 1; and an imaging element that receives an image formed by the zoom lens.

27. 27. The image pickup apparatus according to claim 26, wherein the effective image circle diameter of the image pickup element at the wide-angle end is smaller than the effective image circle diameter at the telephoto end.

28. 28. An imaging system comprising: the zoom lens according to claim 1; and a control unit that controls the zoom lens during zooming.

29. 29. The imaging system according to claim 28, wherein the control unit is configured as a separate unit from the zoom lens and includes a transmission unit that transmits a control signal for controlling the zoom lens.

30. 30. The imaging system according to claim 28, wherein the control unit is configured as a separate unit from the zoom lens and has an operation unit for operating the zoom lens.

31. 31. The imaging system according to claim 28, further comprising a display unit that displays information related to the zoom of the zoom lens.

Images