Zoom lens and imaging device

Abstract

A zoom lens according to the present invention is configured of: a first lens group having a positive refractive power; a second lens group having a negative reflective power; a middle lens group having at least one positive lens group and having a positive refractive power as a whole; and a rear lens group having at least a negative lens group and a positive lens group. When the object distance changes from infinity to a short distance, the negative lens group and the positive lens group in the rear lens group individually move along the optical axis direction with mutually different trajectories, and the negative lens group in the rear lens group moves towards the image surface side. During zooming from the wide angle end to the telephoto end, the first lens group moves toward the object side with respect to the image surface, and the first lens group, the second lens group, the middle lens group, and the rear lens group individually move such that the mutual gaps between adjacent lens groups change along the optical axis.

Description

Zoom lens and imaging device

[0001] The present disclosure relates to a zoom lens and an imaging device.

[0002] There are universal demands for optical systems used in imaging devices to be small and lightweight, have a bright F-number, provide high image quality throughout the entire focusing range, and have a high maximum imaging magnification, all of which must be achieved at a high level. For example, as a zoom lens with a standard angle of view, a positive-lead configuration has been proposed in which a lens group with positive refractive power is positioned closest to the object side and moves toward the object side as the magnification changes, and in which focusing is performed from infinity to close distances by moving multiple lens groups separately to achieve high image quality throughout the entire focusing range (see Patent Documents 1 and 2).

[0003] JP 2015-102588 A International Publication No. 2019 / 97719

[0004] With the configurations proposed in Patent Documents 1 and 2, it is difficult to fully satisfy the above-mentioned demands.

[0005] It is desirable to provide a zoom lens that is small and lightweight, yet has a large aperture and high optical performance, suppresses performance fluctuations due to shooting distance, and has a high maximum shooting magnification, and an imaging device equipped with such a zoom lens.

[0006] A first zoom lens according to an embodiment of the present disclosure includes, in order from the object side to the image plane side, a first lens group having positive refractive power, a second lens group having negative refractive power, an intermediate lens group having at least one positive lens group and having positive refractive power overall, and a rear lens group having, at least from the object side, a negative lens group and a positive lens group. When the object distance changes from infinity to a close distance, the negative lens group and the positive lens group in the rear lens group move along different loci in the optical axis direction, and the negative lens group in the rear lens group moves toward the image plane, thereby performing focusing. When zooming from the wide-angle end to the telephoto end, the first lens group moves toward the object side with respect to the image plane, and the first lens group, the second lens group, the intermediate lens group, and the rear lens group each move so that the spacing between adjacent lens groups changes on the optical axis. The intermediate lens group has at least two negative lenses, and satisfies the following conditional expression: -0.31≦(1−βrp_w ２ ) / [(1-βrn_w ２ ) *βrp_w ２ ]≦0 (1) where, βrn_w: lateral magnification of the negative lens group in the rear lens group at the wide-angle end and when focused on infinity, and βrp_w: lateral magnification of the positive lens group in the rear lens group at the wide-angle end and when focused on infinity.

[0007] A second zoom lens according to an embodiment of the present disclosure is configured to include, in order from the object side to the image plane side, a first lens group having positive refractive power, a second lens group having negative refractive power, an intermediate lens group having at least one positive lens group and having positive refractive power overall, and a rear lens group having, in order from the object side, at least a negative lens group and a positive lens group; when the object distance changes from infinity to a close distance, the negative lens group and the positive lens group in the rear lens group move along different loci in the optical axis direction, and the negative lens group in the rear lens group moves toward the image plane, thereby performing focusing; when zooming from the wide-angle end to the telephoto end, the first lens group moves toward the object side with respect to the image plane, and the first lens group, the second lens group, the intermediate lens group, and the rear lens group each move such that the spacing between adjacent lens groups changes on the optical axis; the first lens group has three lenses, and satisfies the following conditional expression: -0.31≦(1−βrp_w ２ ) / [(1-βrn_w ２ ) *βrp_w ２ ]≦0 (1) where, βrn_w: lateral magnification of the negative lens group in the rear lens group at the wide-angle end and when focused on infinity, and βrp_w: lateral magnification of the positive lens group in the rear lens group at the wide-angle end and when focused on infinity.

[0008] A first imaging device according to one embodiment of the present disclosure includes a zoom lens and an imaging element that outputs an imaging signal corresponding to an optical image formed by the zoom lens, and the zoom lens is configured by the first zoom lens according to the embodiment of the present disclosure.

[0009] A second imaging device according to an embodiment of the present disclosure includes a zoom lens and an imaging element that outputs an imaging signal corresponding to an optical image formed by the zoom lens, and the zoom lens is configured by the second zoom lens according to the embodiment of the present disclosure.

[0010] In the first and second zoom lenses or the first and second image pickup devices according to an embodiment of the present disclosure, the configuration of each lens group is optimized so that the lenses are small and lightweight, yet have a large aperture and high optical performance, and are able to simultaneously suppress performance variations due to shooting distance and achieve a high maximum shooting magnification.

[0011] FIG. 1 is a lens cross-sectional view showing a first configuration example (Example 1) of a zoom lens according to an embodiment of the present disclosure. FIG. 2 is an aberration diagram showing longitudinal aberration of the zoom lens according to Example 1 at the wide-angle end when focused on infinity. FIG. 3 is an aberration diagram showing longitudinal aberration of the zoom lens according to Example 1 at an intermediate position when focused on infinity. FIG. 4 is an aberration diagram showing longitudinal aberration of the zoom lens according to Example 1 at the telephoto end when focused on infinity. FIG. 5 is an aberration diagram showing longitudinal aberration of the zoom lens according to Example 1 at the wide-angle end when focused on a close distance. FIG. 6 is an aberration diagram showing longitudinal aberration of the zoom lens according to Example 1 at an intermediate position when focused on a close distance. FIG. 7 is an aberration diagram showing longitudinal aberration of the zoom lens according to Example 1 at the telephoto end when focused on a close distance. FIG. 8 is an aberration diagram showing lateral aberration of the zoom lens according to Example 1 at the wide-angle end when focused on infinity. FIG. 9 is an aberration diagram showing lateral aberration of the zoom lens according to Example 1 at the intermediate position when focused on infinity. FIG. 10 is an aberration diagram showing lateral aberration of the zoom lens according to Example 1 at the telephoto end when focused on infinity. FIG. 11 is an aberration diagram showing lateral aberration of the zoom lens according to Example 1 at the wide-angle end when focused on a close distance. FIG. 12 is an aberration diagram showing lateral aberration of the zoom lens according to Example 1 at an intermediate position when focused on a close distance. FIG. 13 is an aberration diagram showing lateral aberration of the zoom lens according to Example 1 at the telephoto end when focused on a close distance. FIG. 14 is a lens cross-sectional view showing a second configuration example (Example 2) of the zoom lens according to one embodiment. FIG. 15 is an aberration diagram showing longitudinal aberration of the zoom lens according to Example 2 at the wide-angle end when focused on infinity. FIG. 16 is an aberration diagram showing longitudinal aberration of the zoom lens according to Example 2 at the intermediate position when focused on infinity. FIG. 17 is an aberration diagram showing longitudinal aberration of the zoom lens according to Example 2 at the telephoto end when focused on infinity. Fig. 18 is an aberration diagram showing longitudinal aberration of the zoom lens according to Example 2 at the wide-angle end and when focusing on a close distance. Fig. 19 is an aberration diagram showing longitudinal aberration of the zoom lens according to Example 2 at an intermediate position and when focusing on a close distance. Fig. 20 is an aberration diagram showing longitudinal aberration of the zoom lens according to Example 2 at the telephoto end and when focusing on a close distance. Fig. 21 is an aberration diagram showing lateral aberration of the zoom lens according to Example 2 at the wide-angle end and when focusing on infinity.FIG. 22 is an aberration diagram showing lateral aberration of the zoom lens according to Example 2 at an intermediate position and focused on infinity. FIG. 23 is an aberration diagram showing lateral aberration of the zoom lens according to Example 2 at a telephoto end and focused on infinity. FIG. 24 is an aberration diagram showing lateral aberration of the zoom lens according to Example 2 at a wide-angle end and focused on a close distance. FIG. 25 is an aberration diagram showing lateral aberration of the zoom lens according to Example 2 at an intermediate position and focused on a close distance. FIG. 26 is an aberration diagram showing lateral aberration of the zoom lens according to Example 2 at a telephoto end and focused on a close distance. FIG. 27 is a lens cross-sectional view showing a third configuration example (Example 3) of a zoom lens according to an embodiment. FIG. 28 is an aberration diagram showing longitudinal aberration of the zoom lens according to Example 3 at a wide-angle end and focused on infinity. FIG. 29 is an aberration diagram showing longitudinal aberration of the zoom lens according to Example 3 at an intermediate position and focused on infinity. FIG. 30 is an aberration diagram showing longitudinal aberration of the zoom lens according to Example 3 at the telephoto end when focusing on infinity. FIG. 31 is an aberration diagram showing longitudinal aberration of the zoom lens according to Example 3 at the wide-angle end when focusing on a close distance. FIG. 32 is an aberration diagram showing longitudinal aberration of the zoom lens according to Example 3 at an intermediate position when focusing on a close distance. FIG. 33 is an aberration diagram showing longitudinal aberration of the zoom lens according to Example 3 at the telephoto end when focusing on a close distance. FIG. 34 is an aberration diagram showing lateral aberration of the zoom lens according to Example 3 at the wide-angle end when focusing on infinity. FIG. 35 is an aberration diagram showing lateral aberration of the zoom lens according to Example 3 at an intermediate position when focusing on infinity. FIG. 36 is an aberration diagram showing lateral aberration of the zoom lens according to Example 3 at the telephoto end when focusing on infinity. FIG. 37 is an aberration diagram showing lateral aberration of the zoom lens according to Example 3 at the wide-angle end when focusing on a close distance. Fig. 38 is an aberration diagram showing lateral aberration of the zoom lens according to Example 3 at an intermediate position and when focusing on a close distance. Fig. 39 is an aberration diagram showing lateral aberration of the zoom lens according to Example 3 at a telephoto end and when focusing on a close distance. Fig. 40 is a lens cross-sectional view showing a fourth configuration example (Example 4) of the zoom lens according to an embodiment. Fig. 41 is an aberration diagram showing longitudinal aberration of the zoom lens according to Example 4 at a wide-angle end and when focusing on infinity. Fig. 42 is an aberration diagram showing longitudinal aberration of the zoom lens according to Example 4 at an intermediate position and when focusing on infinity.Fig. 43 is an aberration diagram showing longitudinal aberration of the zoom lens according to Example 4 at the telephoto end when focusing on infinity. Fig. 44 is an aberration diagram showing longitudinal aberration of the zoom lens according to Example 4 at the wide-angle end when focusing on a close distance. Fig. 45 is an aberration diagram showing longitudinal aberration of the zoom lens according to Example 4 at an intermediate position when focusing on a close distance. Fig. 46 is an aberration diagram showing longitudinal aberration of the zoom lens according to Example 4 at the telephoto end when focusing on a close distance. Fig. 47 is an aberration diagram showing lateral aberration of the zoom lens according to Example 4 at the wide-angle end when focusing on infinity. Fig. 48 is an aberration diagram showing lateral aberration of the zoom lens according to Example 4 at an intermediate position when focusing on infinity. Fig. 49 is an aberration diagram showing lateral aberration of the zoom lens according to Example 4 at the telephoto end when focusing on infinity. Fig. 50 is an aberration diagram showing lateral aberration of the zoom lens according to Example 4 at the wide-angle end when focusing on a close distance. FIG. 51 is an aberration diagram showing lateral aberration of the zoom lens according to Example 4 at an intermediate position and when focusing on a close distance. FIG. 52 is an aberration diagram showing lateral aberration of the zoom lens according to Example 4 at a telephoto end and when focusing on a close distance. FIG. 53 is a lens cross-sectional view showing a fifth configuration example (Example 5) of the zoom lens according to an embodiment. FIG. 54 is an aberration diagram showing longitudinal aberration of the zoom lens according to Example 5 at a wide-angle end and when focusing on infinity. FIG. 55 is an aberration diagram showing longitudinal aberration of the zoom lens according to Example 5 at an intermediate position and when focusing on infinity. FIG. 56 is an aberration diagram showing longitudinal aberration of the zoom lens according to Example 5 at a telephoto end and when focusing on infinity. FIG. 57 is an aberration diagram showing longitudinal aberration of the zoom lens according to Example 5 at a wide-angle end and when focusing on a close distance. FIG. 58 is an aberration diagram showing longitudinal aberration of the zoom lens according to Example 5 at an intermediate position and when focusing on a close distance. Fig. 59 is an aberration diagram showing longitudinal aberration of the zoom lens according to Example 5 at the telephoto end when focusing on a close distance. Fig. 60 is an aberration diagram showing lateral aberration of the zoom lens according to Example 5 at the wide-angle end when focusing on infinity. Fig. 61 is an aberration diagram showing lateral aberration of the zoom lens according to Example 5 at an intermediate position when focusing on infinity. Fig. 62 is an aberration diagram showing lateral aberration of the zoom lens according to Example 5 at the telephoto end when focusing on infinity. Fig. 63 is an aberration diagram showing lateral aberration of the zoom lens according to Example 5 at the wide-angle end when focusing on a close distance.Fig. 64 is an aberration diagram showing lateral aberration of the zoom lens according to Example 5 at an intermediate position and when focusing on a close distance. Fig. 65 is an aberration diagram showing lateral aberration of the zoom lens according to Example 5 at a telephoto end and when focusing on a close distance. Fig. 66 is a lens cross-sectional view showing a sixth configuration example (Example 6) of the zoom lens according to an embodiment. Fig. 67 is an aberration diagram showing longitudinal aberration of the zoom lens according to Example 6 at a wide-angle end and when focusing on infinity. Fig. 68 is an aberration diagram showing longitudinal aberration of the zoom lens according to Example 6 at an intermediate position and when focusing on infinity. Fig. 69 is an aberration diagram showing longitudinal aberration of the zoom lens according to Example 6 at a telephoto end and when focusing on infinity. Fig. 70 is an aberration diagram showing longitudinal aberration of the zoom lens according to Example 6 at a wide-angle end and when focusing on a close distance. Fig. 71 is an aberration diagram showing longitudinal aberration of the zoom lens according to Example 6 at an intermediate position and when focusing on a close distance. 72 is an aberration diagram showing longitudinal aberration of the zoom lens according to Example 6 at the telephoto end when focusing on a close distance. FIG. 73 is an aberration diagram showing lateral aberration of the zoom lens according to Example 6 at the wide-angle end when focusing on infinity. FIG. 74 is an aberration diagram showing lateral aberration of the zoom lens according to Example 6 at the intermediate position when focusing on infinity. FIG. 75 is an aberration diagram showing lateral aberration of the zoom lens according to Example 6 at the telephoto end when focusing on infinity. FIG. 76 is an aberration diagram showing lateral aberration of the zoom lens according to Example 6 at the wide-angle end when focusing on a close distance. FIG. 77 is an aberration diagram showing lateral aberration of the zoom lens according to Example 6 at the intermediate position when focusing on a close distance. FIG. 78 is an aberration diagram showing lateral aberration of the zoom lens according to Example 6 at the telephoto end when focusing on a close distance. FIG. 79 is a block diagram showing an example of the configuration of an imaging device. FIG. 80 is a block diagram showing an example of the schematic configuration of a vehicle control system. Fig. 81 is an explanatory diagram showing an example of the installation positions of the vehicle outside information detection unit and the imaging unit. Fig. 82 is a diagram showing an example of the schematic configuration of an endoscope system. Fig. 83 is a block diagram showing an example of the functional configuration of the camera and CCU shown in Fig. 82. Fig. 84 is a diagram showing an example of the schematic configuration of a microsurgical system.

[0012] Hereinafter, embodiments of the present disclosure will be described in detail with reference to the drawings. The description will be made in the following order: 0. Comparative Example 1. Basic Structure of Lens 2. Actions and Effects 3. Application Example to Imaging Device 4. Numerical Examples of Lens 5. Application Example 6. Other Embodiments

[0013] <0. Comparative Example> The zoom lens described in Patent Document 1 (JP 2015-102588 A) has a configuration in which the first lens group and the intermediate lens group are insufficiently optimized to suppress spherical aberration at the telephoto end, which is required as the aperture increases, making it difficult to increase the aperture while maintaining high image quality. In fact, Patent Document 1 does not propose any examples of a large-aperture zoom lens with an F-number of 4 or less at the telephoto end.

[0014] Furthermore, in the variable magnification optical system described in Patent Document 2 (WO 2019 / 97719), the ratio between the amount of movement of the focus lens group and the amount of movement of the image plane, i.e., the relationship between focus sensitivity and the trajectory of the focus lens group, is inappropriate from the perspective of suppressing the focus stroke. For this reason, if an attempt is made to increase the maximum shooting magnification (to increase close-up shooting capability), the focus stroke and therefore the overall length of the optical system become redundant, making the optical system unsuitable for compact, lightweight design and high-speed AF (autofocus).

[0015] Therefore, there is a need for the development of a zoom lens that is small and lightweight, yet has a large aperture and high optical performance, suppresses performance fluctuations due to shooting distance, and has a high maximum shooting magnification.

[0016] 1. Basic Lens Configuration FIG. 1 shows a first configuration example of a zoom lens according to an embodiment of the present disclosure, which corresponds to the configuration of Example 1 described below. FIG. 14 shows a second configuration example of a zoom lens according to an embodiment, which corresponds to the configuration of Example 2 described below. FIG. 27 shows a third configuration example of a zoom lens according to an embodiment, which corresponds to the configuration of Example 3 described below. FIG. 40 shows a fourth configuration example of a zoom lens according to an embodiment, which corresponds to the configuration of Example 4 described below. FIG. 53 shows a fifth configuration example of a zoom lens according to an embodiment, which corresponds to the configuration of Example 5 described below. FIG. 66 shows a sixth configuration example of a zoom lens according to an embodiment, which corresponds to the configuration of Example 6 described below.

[0017] 1 and other figures, Z1 indicates the optical axis. An optical member such as a cover glass for protecting the image sensor may be disposed between the zoom lenses 1 to 6 according to the first to sixth configuration examples and the image plane IMG. In addition to the cover glass, various optical filters such as a low-pass filter and an infrared cut filter may also be disposed as optical members.

[0018] Below, the configuration of a zoom lens according to an embodiment of the present disclosure will be described in association with zoom lenses 1 to 6 according to the respective configuration examples shown in FIG. 1 and the like, as appropriate; however, the technology according to the present disclosure is not limited to the configuration examples shown in the drawings.

[0019] A zoom lens according to one embodiment is composed of, in order from the object side to the image plane side, a first lens group Gr1 having an overall positive refractive power, a second lens group Gr2 having an overall negative refractive power, an intermediate lens group Grm having an overall positive refractive power, and a rear lens group Grr.

[0020] The intermediate lens group Grm has at least one positive lens group. In the examples described below, in the zoom lens 1 according to Example 1, the fourth lens group Gr4 and the fifth lens group Gr5 are positive lens groups in the intermediate lens group Grm. In the zoom lenses 2 to 5 according to Examples 2 to 5, the third lens group Gr3 and the fourth lens group Gr4 are positive lens groups in the intermediate lens group Grm. In the zoom lens 6 according to Example 6, the third lens group Gr3 is a positive lens group in the intermediate lens group Grm.

[0021] The rear lens group Grr has, in order from the object side, at least a negative lens group Grrn and a positive lens group Grrp. In the examples described later, in the zoom lens 1 according to Example 1, the sixth lens group Gr6 is the negative lens group Grrn, and the seventh lens group Gr7 is the positive lens group Grrp. In the zoom lenses 2 to 5 according to Examples 2 to 5, the fifth lens group Gr5 is the negative lens group Grrn, and the sixth lens group Gr6 is the positive lens group Grrp. In the zoom lens 6 according to Example 6, the fourth lens group Gr4 is the negative lens group Grrn, and the fifth lens group Gr5 is the positive lens group Grrp.

[0022] The first lens group Gr1 may have three lenses, and the middle lens group Grm may have at least two negative lenses.

[0023] In a zoom lens according to one embodiment, when the object distance changes from infinity to a close distance, the negative lens group Grrn and the positive lens group Grrp in the rear lens group Grr move along different loci in the optical axis direction, and the negative lens group Grrn in the rear lens group Grr moves toward the image plane, thereby performing focusing. In other words, the negative lens group Grrn and the positive lens group Grrp each function as a focus lens group.

[0024] In addition, in a zoom lens according to an embodiment, when zooming from the wide-angle end (Wide) to the telephoto end (Tele), the first lens group Gr1 moves toward the object side with respect to the image plane IMG, and the first lens group Gr1, the second lens group Gr2, the intermediate lens group Grm, and the rear lens group Grr each move such that the spacing between adjacent lens groups changes on the optical axis. In Figure 1 etc., the upper row shows the lens arrangement when the wide-angle end is at the wide-angle end and focused at infinity, and the lower row shows an outline of the movement locus of each lens group when zooming from the wide-angle end to the telephoto end, indicated by arrows.

[0025] In addition, the zoom lens according to one embodiment may further satisfy certain conditional expressions, etc., which will be described later.

[0026] 2. Actions and Effects Next, the actions and effects of the zoom lens according to an embodiment of the present disclosure will be described. Additionally, a more preferable configuration of the zoom lens according to an embodiment of the present disclosure, and its actions and effects will be described. Note that the effects described in this specification are merely examples and are not intended to be limiting, and other effects may also be present.

[0027] In a zoom lens according to one embodiment, the configuration of each lens group is optimized to achieve a compact, high-performance, and high-zoom ratio zoom lens, and an imaging device equipped with such a zoom lens.

[0028] A zoom lens according to one embodiment of the present invention is configured, in order from the object side to the image plane side, with a first lens group Gr1 having an overall positive refractive power, a second lens group Gr2 having an overall negative refractive power, an intermediate lens group Grm having an overall positive refractive power, and a rear lens group Grr. The intermediate lens group Grm has at least one positive lens group. The rear lens group Grr has, in order from the object side, at least a negative lens group Grrn and a positive lens group Grrp. With this configuration, zooming is performed by changing the spacing between the first lens group Gr1, the second lens group Gr2, the intermediate lens group Grm, and the rear lens group Grr, thereby achieving a large variable magnification effect suitable for a zoom lens.

[0029] Furthermore, by configuring the first lens group Gr1 to have three lenses, or by configuring the intermediate lens group Grm to have at least two negative lenses, it is possible to obtain an aberration correction capability that can withstand a large aperture at the telephoto end.

[0030] In addition, in a zoom lens according to one embodiment, a negative lens group Grrn is disposed immediately after an intermediate lens group Grm having a positive refractive power, and by giving the negative lens group Grrn high focus sensitivity (the ratio of the amount of movement of the image plane position to the unit amount of movement of the group), the negative lens group Grrn contributes to the miniaturization of the lens barrel. The negative lens group Grrn also functions as a focus lens group suitable for high-speed AF. Furthermore, by moving the negative lens group Grrn toward the image plane during focusing, which changes the object distance from infinity to a close distance, the negative lens group Grrn can be given the primary ability to focus on close distances.

[0031] Furthermore, by arranging a positive lens group Grrp as another focus lens group adjacent to the image plane side of the negative lens group Grrn, it becomes possible to overlap the focus strokes of the negative lens group Grrn and the positive lens group Grrp in a single space within the lens barrel, resulting in a configuration advantageous for reducing the size and weight of the lens barrel. Also, by moving the negative lens group Grrn and the positive lens group Grrp as focus lens groups on different trajectories during focusing, the degree of freedom in aberration correction during focusing at a finite object distance is increased, and high optical performance can be achieved throughout the entire focusing range.

[0032] The zoom lens according to an embodiment may satisfy the following conditional expression (1): −0.31≦(1−βrp_w ２ ) / [(1-βrn_w ２ ) *βrp_w ２ ]≦0 (1) where, βrn_w: lateral magnification of the negative lens group Grrn in the rear lens group Grr at the wide-angle end and when focused on infinity, and βrp_w: lateral magnification of the positive lens group Grrp in the rear lens group Grr at the wide-angle end and when focused on infinity.

[0033] Conditional expression (1) relates the lateral magnification of the negative lens group Grrn in the rear lens group Grr to the lateral magnification of the positive lens group Grrp. In pursuit of compact optical systems, the negative lens group Grrn and the positive lens group Grrp are disposed close to each other in the lens barrel. If one of the lens groups Grrn moves significantly toward the image plane beyond a certain stroke amount, the other lens group Grrp also moves toward the image plane to avoid the movement. Given this background, when the lower limit of conditional expression (1) is exceeded, the absolute value of the focus sensitivity of the positive lens group Grrp becomes large relative to the focus sensitivity of the negative lens group Grrn. Furthermore, when focusing to change the object distance from infinity to a close distance, if the negative lens group Grrn is moved significantly toward the image plane to obtain a high maximum imaging magnification, the focus sensitivity of the positive lens group Grrp, which moves to avoid the negative lens group Grrn, is strongly offset, resulting in a longer focus stroke and making it difficult to reduce the lens barrel size. The upper limit of conditional expression (1) is 0 because the negative lens group Grrn has a negative refractive power and the positive lens group Grrp has a positive refractive power.

[0034] It should be noted that a greater effect can be obtained by setting the numerical range of conditional expression (1) to the following conditional expression (1A): −0.28≦(1−βrp_w ２ ) / [(1-βrn_w ２ ) *βrp_w ２ ]≦0 … (1A)

[0035] In a zoom lens according to an embodiment, the intermediate lens group Grm may have at least one lens group including a positive lens group, and at least one lens group in the intermediate lens group Grm may be configured to move relative to the image plane IMG during zooming. This provides a degree of freedom in the relative relationship between that lens group and the other lens groups, making it easier to balance the magnification effect and aberration correction, and improving the imaging performance of the optical system.

[0036] Furthermore, in a zoom lens according to one embodiment, the intermediate lens group Grm may be configured to include two positive lens groups. The intermediate lens group Grm increases the axial ray height and plays an important role in correcting spherical aberration and coma. In the intermediate lens group Grm, the two positive lens groups change their relative relationship and move during zooming, thereby providing flexibility in both the zooming effect and the aberration correction, and realizing a variable-magnification optical system that is suitable for large apertures and has an F-number of 3 or less while covering the standard angle of view within the zooming range. In the examples described below, zoom lenses 1 to 5 according to Examples 1 to 5 have this configuration.

[0037] Furthermore, the zoom lens according to an embodiment may satisfy the following conditional expression (2): 0.60<fm_w / fw<1.60 (2) where, fw: focal length of the entire system at the wide-angle end, and fm_w: focal length of the intermediate lens group Grm at the wide-angle end.

[0038] Conditional expression (2) defines a preferable range for the ratio between the focal length of the entire system at the wide-angle end and the focal length of the middle lens group Grm at the wide-angle end. If the lower limit of conditional expression (2) is not met, the refractive power of the middle lens group Grm at the wide-angle end becomes too strong, making it difficult to correct spherical aberration, coma, and other aberrations at the wide-angle end. On the other hand, if the upper limit of conditional expression (2) is met, the refractive power of the middle lens group Grm becomes too weak, and in order to obtain a desired zoom ratio, it is necessary to ensure a large amount of movement of the middle lens group Grm during zooming, making it difficult to reduce the size of the lens barrel.

[0039] It should be noted that a better effect can be obtained by setting the numerical range of conditional expression (2) as in the following conditional expression (2A): 0.80<fm_w / fw<1.30 (2A)

[0040] Furthermore, the zoom lens according to an embodiment may satisfy the following conditional expression (3): 0.25<fm_t / ft<0.70 (3) where ft is the focal length of the entire system at the telephoto end, and fm_t is the focal length of the intermediate lens group Grm at the telephoto end.

[0041] Conditional expression (3) defines a preferable range for the ratio between the focal length of the entire system at the telephoto end and the focal length of the middle lens group Grm at the telephoto end. If the lower limit of conditional expression (3) is not met, the refractive power of the middle lens group Grm at the telephoto end becomes too strong, making it difficult to correct spherical aberration, coma, and other aberrations at the telephoto end. On the other hand, if the upper limit of conditional expression (3) is exceeded, the refractive power of the middle lens group Grm becomes too weak, and in order to obtain a desired zoom ratio, it is necessary to ensure a large amount of movement of the middle lens group Grm during zooming, making it difficult to reduce the size of the lens barrel.

[0042] It should be noted that a better effect can be obtained by setting the numerical range of conditional expression (3) as in the following conditional expression (3A): 0.28<fm_t / ft<0.50 (3A)

[0043] In addition, in the zoom lens according to one embodiment, the negative lens group Grrn in the rear lens group Grr may be configured as a single lens. By configuring the negative lens group Grrn as a single lens, the negative lens group Grrn can be a focus lens group that is small in volume and lightweight, and the thickness in the optical axis direction can also be reduced. At the same time, the actuator that drives the negative lens group Grrn can also be made smaller, resulting in an optical system that is desirable for reducing the size and weight of the lens barrel.

[0044] In addition, in the zoom lens according to one embodiment, the positive lens group Grrp in the rear lens group Grr may be configured as a single lens. By configuring the positive lens group Grrp as a single lens, the positive lens group Grrp can be a focus lens group that is small in volume and lightweight, and the thickness in the optical axis direction can also be reduced. At the same time, the actuator that drives the positive lens group Grrp can also be made smaller, resulting in an optical system that is desirable for reducing the size and weight of the lens barrel.

[0045] By configuring the negative lens group Grrn as a single lens with negative refractive power and the positive lens group Grrp as a single lens with positive refractive power, the rear lens group Grr is configured such that a negative lens whose edge thickness is relatively large relative to its center thickness and a positive lens whose center thickness is relatively large relative to its edge thickness are connected as adjacent groups.As a result, when the thicknesses of the single lenses constituting the negative lens group Grrn and the positive lens group Grrp are added together in the optical axis direction, the difference in thickness between the lens center and the lens periphery is small.This improves space efficiency and is even more advantageous for reducing the size of the lens barrel.

[0046] Furthermore, the zoom lens according to one embodiment may satisfy the following conditional expression (4): 0.2<BF_w / fw≦1.2 (4), where BF_w is the back focus (the distance from the surface of the rear lens group Grr closest to the image plane to the image plane IMG) at the wide-angle end and when focused at infinity.

[0047] Conditional expression (4) defines a suitable range for the back focal length at the wide-angle end and when focusing at infinity, and is a conditional expression for providing a variable-magnification optical system suitable primarily for interchangeable lenses in interchangeable-lens mirrorless camera systems. If the lower limit of conditional expression (4) is exceeded, the back focal length becomes too short, causing the image plane IMG and the final surface of the zoom lens to become too close, resulting in an optical system unsuitable for interchangeable-lens cameras. If the upper limit of conditional expression (4) is exceeded, the back focal length becomes too long, making it difficult to effectively correct aberrations that cause problems at peripheral image heights, such as distortion, field curvature, and chromatic aberration of magnification, in the lens groups close to the image plane IMG, resulting in an optical system that fails to take advantage of the advantages of interchangeable-lens mirrorless camera systems. Furthermore, if the back focal length becomes too long, the negative power of the second lens group Gr2 becomes too strong, making it difficult to suppress aberrations that occur in the second lens group Gr2.

[0048] It should be noted that a better effect can be obtained by setting the numerical range of conditional expression (4) as in the following conditional expression (4A): 0.4<BF_w / fw≦1.0 (4)

[0049] Furthermore, in a zoom lens according to an embodiment, the first lens group Gr1 may have a lens L1i that satisfies the following conditional expression (5). Note that in the examples described below, in zoom lenses 1 to 6 according to Examples 1 to 6, the lens L11 corresponds to the lens L1i that satisfies the conditional expression (5): nd_L1i / dL1i>0.50 (5) where, nd_L1i: refractive index at the d-line of the glass material of the lens L1i in the first lens group Gr1 that satisfies the conditional expression (5), and d_L1i: ratio (specific gravity) of the mass of the glass material of the lens L1i in the first lens group Gr1 that satisfies the conditional expression (5) at room temperature (15 degrees Celsius to 25 degrees Celsius) to the mass of the same volume of pure water at 4 degrees Celsius under a pressure of 101.325 kPa (standard atmospheric pressure).

[0050] Conditional expression (5) defines a suitable condition for the relationship between the refractive index and specific gravity of the lens L1i in the first lens group Gr1 relative to the d-line. In general, in zoom lenses, the lens diameter of the first lens group Gr1, which is the leading lens group, is often the largest in the optical system, and therefore reducing the weight of the first lens group Gr1 is important in reducing the overall lens barrel weight. The specifications required for the optical system require the first lens group Gr1 to have a certain refractive power. However, it is obvious that, when imparting the same refractive power to a lens group, using a glass material with a higher refractive index can reduce the lens volume. Meanwhile, since the glass materials typically used in camera lenses tend to have a higher specific gravity as their refractive index increases, simply pursuing a higher refractive index can result in a heavier lens weight due to the increased specific gravity. However, some glass materials have a relatively low specific gravity relative to their refractive index. Therefore, by using a glass material with a large refractive index / specific gravity value, it is possible to realize an optical system that is suitable for reducing the weight of the first lens group Gr1, and ultimately the entire lens barrel, while obtaining the desired refractive index. If the lower limit of conditional expression (5) is not met, the glass material selected will have a refractive index / specific gravity ratio that is not conducive to weight reduction, and the weight of the lens barrel will increase.

[0051] Furthermore, in a zoom lens according to an embodiment, the second lens group Gr2 may have a positive lens L2p that satisfies the following conditional expression (6). Note that in the examples described below, in the zoom lens 1 according to Example 1, the lens L23 corresponds to the positive lens L2p that satisfies the conditional expression (6). In the zoom lenses 2 to 6 according to Examples 2 to 6, the lens L24 corresponds to the positive lens L2p that satisfies the conditional expression (6). 1.955<nd_L2p (6) where, nd_L2p: refractive index for the d-line of the positive lens L2p in the second lens group Gr2 that satisfies the conditional expression (6).

[0052] By using a high-refractive-index glass material that satisfies conditional expression (6) for the positive lens L2p in the second lens group Gr2, the central thickness of the positive lens L2p can be reduced, and the thickness of the second lens group Gr2 can be reduced. In general, reducing the thickness of a lens group not only contributes to the miniaturization of the lens barrel itself, but also makes it possible to ensure a greater amount of movement of the lens group during zooming, making it an effective means of miniaturization without increasing the refractive power of the lens group, which would make manufacturing more difficult. If the value falls below the lower limit of conditional expression (6), the refractive index will be lowered, and in order for the positive lens L2p to maintain the same refractive power, it will be necessary to compensate for this with refractive power due to curvature, which will increase the central thickness of the positive lens L2p, resulting in an optical system that is not desirable for miniaturizing the lens barrel, etc.

[0053] In a zoom lens according to an embodiment, the intermediate lens group Grm may include a positive lens Lmp_asp on which an aspherical surface having a partial negative refractive action is formed. In the examples described below, in the zoom lens 1 according to Example 1, the lens L41 corresponds to the positive lens Lmp_asp on which this aspherical surface is formed. In the zoom lenses 2 to 5 according to Examples 2 to 5, the lens L31 corresponds to the positive lens Lmp_asp on which this aspherical surface is formed.

[0054] The middle lens group Grm is a lens group in which the height of on-axis marginal rays increases due to the negative refractive power of the second lens group Gr2, and correction of spherical aberration becomes a challenge when increasing the aperture. Because the middle lens group Grm has positive refractive power as a whole, it inevitably contains many lenses and surfaces with positive refractive action, but in order to offset the positive spherical aberration of these surfaces, surfaces with strong negative refractive power are required within the middle lens group Grm. If such surfaces were provided solely with spherical surfaces, lenses with strong negative refractive power would be required, and such lenses would have an extremely large edge thickness relative to their center thickness, which is disadvantageous in terms of reducing the thickness of the middle lens group Grm and shortening the overall optical length. Therefore, for example, by providing a refractive surface in the intermediate lens group Grm that has a positive paraxial refractive power but is provided with an aspherical surface with a negative refractive action that cancels out spherical aberration in the peripheral area, it becomes possible to correct spherical aberration well without the need for an extremely negative refractive surface that would be detrimental to reducing the thickness of the intermediate lens group Grm and the overall optical length, and this is suitable for use as an optical system for a large-aperture zoom lens.

[0055] In the zoom lens according to one embodiment, the first lens group Gr1 may have a positive lens L1p that satisfies the following conditional expression (7). Note that in the examples described below, in zoom lenses 1 to 6 according to Examples 1 to 6, the lens L12 corresponds to the positive lens L1p that satisfies the conditional expression (7). θgF_L1p-(-0.001801*νd_L1p+0.648262)>0.005 (7) where θgF_L1p: partial dispersion ratio between the g-line and the F-line of the positive lens L1p in the first lens group Gr1 that satisfies the conditional expression (7), and νd_L1p: Abbe number for the d-line of the positive lens L1p in the first lens group Gr1 that satisfies the conditional expression (7).

[0056] Conditional expression (7) defines a suitable range for the anomalous dispersion of the positive lens L1p in the first lens group Gr1. By using a glass material with high anomalous dispersion that satisfies conditional expression (7) for the positive lens L1p in the first lens group Gr1, balanced correction of axial chromatic aberration and chromatic aberration of magnification becomes possible for wavelengths in the range from the g-line to the F-line from the wide-angle end to the telephoto end. If the lower limit of conditional expression (7) is not satisfied, correction of chromatic aberration becomes insufficient.

[0057] It should be noted that a greater effect can be obtained by setting the numerical range of conditional expression (7) as in the following conditional expression (7A): θgF_L1p−(−0.001801*νd_L1p+0.648262)>0.010 (7A)

[0058] In a zoom lens according to an embodiment, the first lens group Gr1 may have a negative lens L1n that satisfies the following conditional expression (8). In the examples described below, in zoom lenses 1 to 6 according to Examples 1 to 6, the lens L11 corresponds to the negative lens L1n that satisfies the conditional expression (8): νd_L1n<23.0 (8) where νd_L1n: Abbe number for the d-line of the negative lens L1n in the first lens group Gr1 that satisfies the conditional expression (8).

[0059] Conditional expression (8) defines a suitable range for the Abbe number of the negative lens L1n in the first lens group Gr1. By using a glass material with a small Abbe number and large dispersion that satisfies conditional expression (8) for the negative lens L1n in the first lens group Gr1, it is possible to achieve good correction of axial chromatic aberration in the first lens group Gr1, which has positive refractive power as a whole, and to achieve good correction of lateral chromatic aberration from the wide-angle end to the telephoto end. If the upper limit of conditional expression (8) is exceeded, correction of chromatic aberration becomes insufficient.

[0060] It should be noted that a better effect can be obtained by setting the numerical range of conditional expression (8) as in the following conditional expression (8A): νd_L1n<21.0 (8A)

[0061] In a zoom lens according to an embodiment, the intermediate lens group Grm may have a positive lens Lmp that satisfies the following conditional expression (9). In the examples described below, in a zoom lens 1 according to Example 1, lenses L42 and L53 correspond to the positive lens Lmp that satisfies conditional expression (9). In zoom lenses 2 to 5 according to Examples 2 to 5, lenses L32 and L43 correspond to the positive lens Lmp that satisfies conditional expression (9). In a zoom lens 6 according to Example 6, lenses L32 and L36 correspond to the positive lens Lmp that satisfies conditional expression (9). θgF_Lmp−(−0.001801*νd_Lmp+0.648262)>0.045 (9) where, θgF_Lmp: partial dispersion ratio for the g-line and the F-line of the positive lens Lmp in the intermediate lens group Grm that satisfies conditional expression (9), and νd_Lmp: Abbe number for the d-line of the positive lens Lmp in the intermediate lens group Grm that satisfies conditional expression (9).

[0062] Conditional expression (9) defines a suitable range of anomalous dispersion for the positive lens Lmp in the middle lens group Grm. By using a glass material with large anomalous dispersion that satisfies conditional expression (9) for the positive lens Lmp in the middle lens group Grm, where axial rays are high, it becomes possible to achieve good correction of axial chromatic aberration at wavelengths ranging from the g-line to the F-line from the wide-angle end to the telephoto end. If the lower limit of conditional expression (9) is not satisfied, correction of chromatic aberration becomes insufficient.

[0063] It should be noted that a better effect can be obtained by setting the numerical range of conditional expression (9) as in the following conditional expression (9A): θgF_Lmp−(−0.001801*νd_Lmp+0.648262)>0.050 (9A)

[0064] Furthermore, in a zoom lens according to an embodiment, the lens Lrr in the rear lens group Grr that is located closest to the image plane may be configured as a negative lens that satisfies the following conditional expression (10). Note that in the examples described below, in the zoom lens 1 according to Example 1, the lens L83 corresponds to the lens Lrr that satisfies the conditional expression (10). In the zoom lenses 2 to 5 according to Examples 2 to 5, the lens L72 corresponds to the lens Lrr that satisfies the conditional expression (10). 0.9<(r2_rr+r1_rr) / (r2_rr-r1_rr)<6.9 (10) where, r1_rr: radius of curvature of the object-side surface of the lens Lrr that is located closest to the image plane in the rear lens group Grr, r2_rr: radius of curvature of the image-side surface of the lens Lrr that is located closest to the image plane in the rear lens group Grr.

[0065] Conditional expression (10) defines the shape factor. A negative lens that satisfies conditional expression (10) is a concave meniscus lens with a convex, flat, or very gently concave surface facing the image plane side. By adopting this shape, if the final lens of a zoom lens according to one embodiment has an abutment surface for a lens frame component on the object side, the effective optical path diameter of the image plane side surface can be secured at a larger ratio compared to the lens diameter. Below the lower limit of conditional expression (10), the final lens surface becomes a concave surface with a strong concave shape facing the image plane IMG, making it difficult to effectively utilize the space at the rear of the lens barrel. Above the upper limit of conditional expression (10), the power of the negative lens becomes too strong, resulting in insufficient correction of off-axis aberrations such as distortion and field curvature.

[0066] Furthermore, a greater effect can be achieved by setting the numerical range of conditional expression (10) as in the following conditional expression (10A). By setting the lower limit to a value greater than 1, the image-side surface of lens Lrr is shaped to protrude toward the image side, making it possible to effectively utilize the back focus space. 1.0<(r2_rr+r1_rr) / (r2_rr-r1_rr)<4.0 (10A)

[0067] 3. Application Example to Imaging Device Next, a specific application example to an imaging device of the zoom lens according to an embodiment of the present disclosure will be described.

[0068] 79 shows an example of the configuration of an image pickup device 100 to which a zoom lens according to one embodiment is applied. This image pickup device 100 is, for example, a digital still camera, and includes a camera block 110, a camera signal processing unit 20, an image processing unit 30, an LCD (Liquid Crystal Display) 40, an R / W (Reader / Writer) 50, a CPU (Central Processing Unit) 60, an input unit 70, and a lens drive control unit 80.

[0069] The camera block 110 is responsible for the imaging function and includes an imaging lens 111 and an imaging element 112 such as a CCD (Charge Coupled Device) or a CMOS (Complementary Metal Oxide Semiconductor). The imaging element 112 converts an optical image formed by the imaging lens 111 into an electrical signal, and outputs an imaging signal (image signal) corresponding to the optical image. The zoom lenses 1 to 6 according to the configuration examples shown in FIG. 1 and the like can be used as the imaging lens 111.

[0070] The camera signal processing unit 20 performs various signal processing on the image signal output from the image sensor 112, such as analog-to-digital conversion, noise removal, image quality correction, and conversion into luminance and color difference signals.

[0071] The image processing unit 30 performs recording and playback processing of image signals, and performs compression encoding and decompression decoding processing of image signals based on a predetermined image data format, conversion processing of data specifications such as resolution, etc.

[0072] The LCD 40 has a function of displaying various data such as the operation status of the user on the input unit 70 and captured images. The R / W 50 writes image data encoded by the image processing unit 30 to the memory card 1000 and reads image data recorded on the memory card 1000. The memory card 1000 is, for example, a semiconductor memory that is detachable from a slot connected to the R / W 50.

[0073] The CPU 60 functions as a control processing unit that controls each circuit block provided in the imaging device 100, and controls each circuit block based on instruction input signals and the like from the input unit 70. The input unit 70 is made up of various switches and the like that are operated as required by the user. The input unit 70 is composed of, for example, a shutter release button for operating the shutter and a selection switch for selecting an operation mode, and is configured to output instruction input signals to the CPU 60 in response to user operations. The lens drive control unit 80 controls the drive of the lenses arranged in the camera block 110, and is configured to control motors and the like (not shown) that drive each lens of the imaging lens 111 based on control signals from the CPU 60.

[0074] The following describes the operation of the imaging device 100. In a standby state for imaging, under the control of the CPU 60, an image signal corresponding to an image captured by the camera block 110 is output to the LCD 40 via the camera signal processing unit 20 and displayed as a camera-through image. Furthermore, when an instruction input signal for zooming or focusing is input from the input unit 70, for example, the CPU 60 outputs a control signal to the lens drive control unit 80, and a predetermined lens of the imaging lens 111 moves under the control of the lens drive control unit 80.

[0075] When a shutter (not shown) of the camera block 110 is operated in response to an instruction input signal from the input unit 70, the captured image signal is output from the camera signal processing unit 20 to the image processing unit 30, where it is compressed and encoded and converted into digital data in a predetermined data format. The converted data is output to the R / W 50 and written to the memory card 1000.

[0076] Focusing is performed by the lens drive control unit 80 moving a predetermined lens of the imaging lens 111 based on a control signal from the CPU 60, for example, when the shutter release button on the input unit 70 is pressed halfway or fully pressed for recording (photographing).

[0077] When reproducing image data recorded on memory card 1000, the R / W 50 reads out the specified image data from memory card 1000 in response to an operation on input unit 70, and after the image processing unit 30 performs an expansion / decoding process, the reproduced image signal is output to LCD 40 and the reproduced image is displayed.

[0078] Although the above-described embodiment shows an example in which the imaging device is applied to a digital still camera, the application range of the imaging device is not limited to digital still cameras and can be applied to various other imaging devices. For example, the imaging device can be applied to digital single-lens reflex cameras, digital non-reflex cameras, digital video cameras, surveillance cameras, etc. Furthermore, the imaging device can be widely used as a camera unit of digital input / output devices such as mobile phones with built-in cameras and information terminals with built-in cameras. Furthermore, the imaging device can be applied to cameras with interchangeable lenses.

[0079] 4. Numerical Examples of Lenses Next, specific numerical examples of the zoom lens according to an embodiment of the present disclosure will be described. Here, examples will be described in which specific numerical values ​​are applied to zoom lenses 1 to 6 according to the configuration examples shown in FIG. 1 etc.

[0080] The meanings of symbols used in the following tables and explanations are as follows: "Si" indicates the number of the i-th surface, with the symbols increasing sequentially from the surface closest to the object. "ri" indicates the value (mm) of the paraxial radius of curvature of the i-th surface. "di" indicates the value (mm) of the axial distance between the i-th surface and the (i+1)-th surface. "ndi" indicates the value of the refractive index at the d-line (wavelength 587.6 nm) of the material of the optical element that comprises the i-th surface. "νdi" indicates the value of the Abbe number at the d-line of the material of the optical element that comprises the i-th surface. "φi" indicates the value (mm) of the effective diameter of the i-th surface. A portion where the value of "ri" is "∞" indicates a flat surface, a diaphragm surface, etc. "ASP" in the surface number (Si) column indicates that the surface in question is configured with an aspherical shape. "STO" in the surface number column indicates that an aperture diaphragm St is disposed at the corresponding position. "OBJ" in the surface number column indicates that the surface in question is the object plane (subject plane). "IMG" in the surface number column indicates that the surface in question is the image plane. "f" indicates the focal length of the entire system (unit: mm). "Fno" indicates the maximum aperture (F-number). "ω" indicates the half angle of view (unit: °). "Y" indicates the image height (unit: mm). "L" indicates the total optical length (the distance on the optical axis from the surface closest to the object to the image plane IMG) (unit: mm).

[0081] Furthermore, some of the lenses used in each embodiment have aspherical lens surfaces. The aspherical shape is defined by the following formula. In the tables showing aspherical coefficients described later, "E-i" is an exponential expression with the base 10, that is, "10 －ｉ " For example, "0.12345E-05" represents "0.12345 x 10 －５ " represents.

[0082] (Aspherical surface formula) x = c ２ y ２ / (1+(1-(1+k)c ２ y ２ ) １／２ ) + A4・y ４ +A6・y ６ +A8・y ８ +A10·y １０ +A12·y １２ +A14·y１４ Here, the distance from the vertex of the lens surface in the optical axis direction (sag amount) is "x," the height in the direction perpendicular to the optical axis is "y," the paraxial curvature (the reciprocal of the radius of curvature) at the vertex of the lens surface is "c," and the conic constant is "k." A4, A6, A8, A10, A12, and A14 are the 4th-, 6th-, 8th-, 10th-, 12th-, and 14th-order aspheric coefficients, respectively.

[0083] Example 1 Table 1 shows basic lens data for the zoom lens 1 according to Example 1 shown in FIG. 1 . Table 2 shows values ​​for the focal length f, F-number, total angle of view 2ω, image height Y, and total optical length L of the entire system of the zoom lens 1 according to Example 1. Table 3 shows data on surface separations that are variable during zooming and focusing in the zoom lens 1 according to Example 1. Table 3 also shows values ​​for the magnification β of the zoom lens 1 according to Example 1. Table 2 also shows values ​​for the wide-angle end (Wide), the middle position (Mid), and the telephoto end (Tele) when the object distance (d0) is infinity. Table 3 also shows values ​​for the wide-angle end (Wide), the middle position (Mid), and the telephoto end (Tele) when the object distance (d0) is infinity and when the object distance is close. Table 4 also shows values ​​for the wide-angle end (Wide), the middle position (Mid), and the telephoto end (Tele) when the object distance (d0) is infinity and when the object distance is close. Table 5 shows the initial surface and focal length (unit: mm) of each lens group of the zoom lens 1 according to Example 1.

[0084] The zoom lens 1 according to Example 1 has a configuration in which the first lens group Gr1 to the eighth lens group Gr8 are arranged in this order from the object side to the image plane side. An aperture stop St is arranged on the object side of the fourth lens group Gr4. The third lens group Gr3 to the fifth lens group Gr5 form the intermediate lens group Grm. The sixth lens group Gr6 to the eighth lens group Gr8 form the rear lens group Grr. Note that, for example, a flare cutter whose diameter changes during zooming may be arranged on the image plane side (surface No. 27) of the fifth lens group Gr5 in order to improve peripheral optical performance.

[0085] The first lens group Gr1 has positive refractive power. The first lens group Gr1 is composed of, in order from the object side to the image plane side, lenses L11 to L13. The lens L11 corresponds to the lens L1i that satisfies the above conditional expression (5). The lens L11 corresponds to the negative lens L1n that satisfies the above conditional expression (8). The lens L12 corresponds to the positive lens L1p that satisfies the above conditional expression (7).

[0086] The second lens group Gr2 has negative refractive power and is composed of, in order from the object side to the image plane side, lenses L21 to L23. The lens L23 corresponds to the positive lens L2p that satisfies the above conditional expression (6).

[0087] The third lens group Gr3 has negative refractive power and is made up of a lens L31.

[0088] The fourth lens group Gr4 has positive refractive power. The fourth lens group Gr4 is composed of, in order from the object side to the image plane side, lenses L41 to L43. The lens L41 corresponds to the positive lens Lmp_asp having an aspherical surface. The lens L42 corresponds to the positive lens Lmp that satisfies the above conditional expression (9).

[0089] The fifth lens group Gr5 has positive refractive power and is composed of, in order from the object side to the image plane side, lenses L51 to L55. The lens L53 corresponds to the positive lens Lmp that satisfies the above conditional expression (9).

[0090] The sixth lens group Gr6 has negative refractive power and is made up of a lens L61. The sixth lens group Gr6 is a focus lens group that corresponds to the negative lens group Grrn in the rear lens group Grr.

[0091] The seventh lens group Gr7 has positive refractive power and is made up of a lens L71. The seventh lens group Gr7 is a focus lens group that corresponds to the positive lens group Grrp in the rear lens group Grr.

[0092] The eighth lens group Gr8 has negative refractive power and is composed of, in order from the object side to the image plane side, lenses L81 to L83. The lens L83 corresponds to the lens Lrr that satisfies the above conditional expression (10).

[0093] During zooming from the wide-angle end to the telephoto end, the first lens group Gr1 moves toward the object side relative to the image plane IMG, and each of the first to seventh lens groups Gr1 to Gr7 moves so that the spacing between adjacent lens groups changes.

[0094] When the object distance changes from infinity to a close distance, focusing is performed by the sixth lens group Gr6 and the seventh lens group Gr7 moving in the optical axis direction along different trajectories, and when the object distance changes from infinity to a close distance, focusing is performed by the sixth lens group Gr6 moving toward the image plane.

[0095] The above configuration realizes a zoom lens that is small and lightweight, yet has a large aperture and high optical performance, suppresses performance fluctuations due to shooting distance, and achieves a high maximum shooting magnification.

[0096]

[0097]

[0098]

[0099]

[0100]

[0101] FIG. 2 shows longitudinal aberration of the zoom lens 1 according to Example 1 at the wide-angle end when focused at infinity. FIG. 3 shows longitudinal aberration of the zoom lens 1 according to Example 1 at an intermediate position when focused at infinity. FIG. 4 shows longitudinal aberration of the zoom lens 1 according to Example 1 at the telephoto end when focused at infinity. FIG. 5 shows longitudinal aberration of the zoom lens 1 according to Example 1 at the wide-angle end when focused at a close distance. FIG. 6 shows longitudinal aberration of the zoom lens 1 according to Example 1 at an intermediate position when focused at a close distance. FIG. 7 shows longitudinal aberration of the zoom lens 1 according to Example 1 at the telephoto end when focused at a close distance. FIG. 8 shows lateral aberration of the zoom lens 1 according to Example 1 at the wide-angle end when focused at infinity. FIG. 9 shows lateral aberration of the zoom lens 1 according to Example 1 at an intermediate position when focused at infinity. FIG. 10 shows lateral aberration of the zoom lens 1 according to Example 1 at the telephoto end when focused at infinity. Fig. 11 shows the lateral aberration of the zoom lens 1 according to Example 1 at the wide-angle end and when focusing on a close distance. Fig. 12 shows the lateral aberration of the zoom lens 1 according to Example 1 at the intermediate position and when focusing on a close distance. Fig. 13 shows the lateral aberration of the zoom lens 1 according to Example 1 at the telephoto end and when focusing on a close distance.

[0102] 2 to 7 show spherical aberration, astigmatism (field curvature), and distortion as longitudinal aberrations. In the spherical aberration diagrams in FIGS. 2 to 7 and the lateral aberration diagrams in FIGS. 8 to 13, the solid line shows values ​​at the d-line (587.56 nm), the dashed-dotted line shows values ​​at the g-line (435.84 nm), and the dashed line shows values ​​at the C-line (656.27 nm). In the astigmatism diagrams in FIGS. 2 to 7, S shows values ​​at the sagittal image plane, and T shows values ​​at the tangential image plane. The astigmatism diagrams and distortion diagrams in FIGS. 2 to 7 show values ​​at the d-line. The same applies to the aberration diagrams in the other examples that follow.

[0103] As can be seen from each aberration diagram, the zoom lens 1 according to Example 1 has excellent correction of various aberrations and has excellent imaging performance.

[0104] Example 2 Table 6 shows basic lens data for the zoom lens 2 according to Example 2 shown in FIG. 14 . Table 7 shows the values ​​of the focal length f, F-number, total angle of view 2ω, image height Y, and total optical length L of the entire system for the zoom lens 2 according to Example 2. Table 8 shows data on surface separations that are variable during zooming and focusing for the zoom lens 2 according to Example 2. Table 8 also shows the value of the magnification β for the zoom lens 2 according to Example 2. Table 7 also shows values ​​for the wide-angle end (Wide), the middle position (Mid), and the telephoto end (Tele) when the object distance (d0) is infinity. Table 8 also shows values ​​for the wide-angle end (Wide), the middle position (Mid), and the telephoto end (Tele) when the object distance (d0) is infinity and when the object distance is close. Table 9 also shows values ​​of coefficients representing the shape of the aspherical surfaces for the zoom lens 2 according to Example 2. Table 10 shows the initial surface and focal length (unit: mm) of each lens group of the zoom lens 2 according to Example 2.

[0105] The zoom lens 2 according to Example 2 has a configuration in which the first lens group Gr1 to the seventh lens group Gr7 are arranged in this order from the object side to the image plane side. An aperture stop St is arranged on the object side of the third lens group Gr3. The third lens group Gr3 and the fourth lens group Gr4 form the intermediate lens group Grm. The fifth lens group Gr5 to the seventh lens group Gr7 form the rear lens group Grr. Note that, for example, a flare cutter whose diameter changes during zooming may be arranged on the object side of the fourth lens group Gr4 (surface No. 21) in order to improve peripheral optical performance.

[0106] The first lens group Gr1 has positive refractive power. The first lens group Gr1 is composed of, in order from the object side to the image plane side, lenses L11 to L13. The lens L11 corresponds to the lens L1i that satisfies the above conditional expression (5). The lens L11 corresponds to the negative lens L1n that satisfies the above conditional expression (8). The lens L12 corresponds to the positive lens L1p that satisfies the above conditional expression (7).

[0107] The second lens group Gr2 has negative refractive power and is composed of, in order from the object side to the image plane side, lenses L21 to L25. The lens L24 corresponds to the positive lens L2p that satisfies the above conditional expression (6).

[0108] The third lens group Gr3 has positive refractive power. The third lens group Gr3 is composed of, in order from the object side to the image plane side, lenses L31 to L33. The lens L31 corresponds to the positive lens Lmp_asp having an aspherical surface. The lens L32 corresponds to the positive lens Lmp that satisfies the above conditional expression (9).

[0109] The fourth lens group Gr4 has positive refractive power and is composed of, in order from the object side to the image plane side, lenses L41 to L45. The lens L43 corresponds to the positive lens Lmp that satisfies the above conditional expression (9).

[0110] The fifth lens group Gr5 has negative refractive power and is made up of a lens L51. The fifth lens group Gr5 is a focus lens group that corresponds to the negative lens group Grrn in the rear lens group Grr.

[0111] The sixth lens group Gr6 has positive refractive power and is made up of a lens L61. The sixth lens group Gr6 is a focus lens group that corresponds to the positive lens group Grrp in the rear lens group Grr.

[0112] The seventh lens group Gr7 has negative refractive power and is composed of, in order from the object side to the image plane side, a lens L71 and a lens L72. The lens L72 corresponds to the lens Lrr that satisfies the above conditional expression (10).

[0113] During zooming from the wide-angle end to the telephoto end, the first lens group Gr1 moves toward the object side relative to the image plane IMG, and each of the first to sixth lens groups Gr1 to Gr6 moves so that the spacing between adjacent lens groups changes.

[0114] When the object distance changes from infinity to a close distance, focusing is performed by the fifth lens group Gr5 and the sixth lens group Gr6 moving in the optical axis direction along different trajectories, and when the object distance changes from infinity to a close distance, focusing is performed by the fifth lens group Gr5 moving toward the image plane.

[0115] The above configuration realizes a zoom lens that is small and lightweight, yet has a large aperture and high optical performance, suppresses performance fluctuations due to shooting distance, and achieves a high maximum shooting magnification.

[0116]

[0117]

[0118]

[0119]

[0120]

[0121] FIG. 15 shows longitudinal aberration of the zoom lens 2 according to Example 2 at the wide-angle end when focused on infinity. FIG. 16 shows longitudinal aberration of the zoom lens 2 according to Example 2 at an intermediate position when focused on infinity. FIG. 17 shows longitudinal aberration of the zoom lens 2 according to Example 2 at the telephoto end when focused on infinity. FIG. 18 shows longitudinal aberration of the zoom lens 2 according to Example 2 at the wide-angle end when focused on a close distance. FIG. 19 shows longitudinal aberration of the zoom lens 2 according to Example 2 at an intermediate position when focused on a close distance. FIG. 20 shows longitudinal aberration of the zoom lens 2 according to Example 2 at the telephoto end when focused on a close distance. FIG. 21 shows lateral aberration of the zoom lens 2 according to Example 2 at the wide-angle end when focused on infinity. FIG. 22 shows lateral aberration of the zoom lens 2 according to Example 2 at an intermediate position when focused on infinity. FIG. 23 shows lateral aberration of the zoom lens 2 according to Example 2 at the telephoto end when focused on infinity. Fig. 24 shows the lateral aberration of the zoom lens 2 according to Example 2 at the wide-angle end and when focusing on a close distance. Fig. 25 shows the lateral aberration of the zoom lens 2 according to Example 2 at the intermediate position and when focusing on a close distance. Fig. 26 shows the lateral aberration of the zoom lens 2 according to Example 2 at the telephoto end and when focusing on a close distance.

[0122] As can be seen from each aberration diagram, the zoom lens 2 according to Example 2 has excellent correction of various aberrations and has excellent imaging performance.

[0123] [Example 3] Table 11 shows basic lens data for the zoom lens 3 according to Example 3 shown in FIG. 27 . Table 12 shows values ​​for the focal length f, F-number, full angle of view 2ω, image height Y, and total optical length L of the entire system of the zoom lens 3 according to Example 3. Table 13 shows data on surface separations that are variable during zooming and focusing in the zoom lens 3 according to Example 3. Table 13 also shows values ​​for the magnification β of the zoom lens 3 according to Example 3. Table 12 shows values ​​for the wide-angle end (Wide), the middle position (Mid), and the telephoto end (Tele) when the object distance (d0) is infinity. Table 13 shows values ​​for the wide-angle end (Wide), the middle position (Mid), and the telephoto end (Tele) when the object distance (d0) is infinity and when the object distance is close. Table 14 shows the values ​​of coefficients representing the shape of the aspherical surface in the zoom lens 3 according to Example 3. Table 15 shows the first surface and focal length (unit: mm) of each lens group in the zoom lens 3 according to Example 3.

[0124] The zoom lens 3 according to Example 3 has a configuration in which the first lens group Gr1 to the seventh lens group Gr7 are arranged in this order from the object side to the image plane side. An aperture stop St is arranged on the object side of the third lens group Gr3. The third lens group Gr3 and the fourth lens group Gr4 form the intermediate lens group Grm. The fifth lens group Gr5 to the seventh lens group Gr7 form the rear lens group Grr. Note that, for example, a flare cutter whose diameter changes during zooming may be arranged on the object side of the fourth lens group Gr4 (surface No. 21) in order to improve peripheral optical performance.

[0125] The first lens group Gr1 has positive refractive power. The first lens group Gr1 is composed of, in order from the object side to the image plane side, lenses L11 to L13. The lens L11 corresponds to the lens L1i that satisfies the above conditional expression (5). The lens L11 corresponds to the negative lens L1n that satisfies the above conditional expression (8). The lens L12 corresponds to the positive lens L1p that satisfies the above conditional expression (7).

[0126] The second lens group Gr2 has negative refractive power and is composed of, in order from the object side to the image plane side, lenses L21 to L25. The lens L24 corresponds to the positive lens L2p that satisfies the above conditional expression (6).

[0127] The third lens group Gr3 has positive refractive power. The third lens group Gr3 is composed of, in order from the object side to the image plane side, lenses L31 to L33. The lens L31 corresponds to the positive lens Lmp_asp having an aspherical surface. The lens L32 corresponds to the positive lens Lmp that satisfies the above conditional expression (9).

[0128] The fourth lens group Gr4 has positive refractive power and is composed of, in order from the object side to the image plane side, lenses L41 to L45. The lens L43 corresponds to the positive lens Lmp that satisfies the above conditional expression (9).

[0129] The fifth lens group Gr5 has negative refractive power and is made up of a lens L51. The fifth lens group Gr5 is a focus lens group that corresponds to the negative lens group Grrn in the rear lens group Grr.

[0130] The sixth lens group Gr6 has positive refractive power and is made up of a lens L61. The sixth lens group Gr6 is a focus lens group that corresponds to the positive lens group Grrp in the rear lens group Grr.

[0131] The seventh lens group Gr7 has negative refractive power and is composed of, in order from the object side to the image plane side, a lens L71 and a lens L72. The lens L72 corresponds to the lens Lrr that satisfies the above conditional expression (10).

[0132] During zooming from the wide-angle end to the telephoto end, the first lens group Gr1 moves toward the object side relative to the image plane IMG, and each of the first to seventh lens groups Gr1 to Gr7 moves so that the spacing between adjacent lens groups changes.

[0133] When the object distance changes from infinity to a close distance, focusing is performed by the fifth lens group Gr5 and the sixth lens group Gr6 moving in the optical axis direction along different trajectories, and when the object distance changes from infinity to a close distance, focusing is performed by the fifth lens group Gr5 moving toward the image plane.

[0134] The above configuration realizes a zoom lens that is small and lightweight, yet has a large aperture and high optical performance, suppresses performance fluctuations due to shooting distance, and achieves a high maximum shooting magnification.

[0135]

[0136]

[0137]

[0138]

[0139]

[0140] FIG. 28 shows longitudinal aberration of the zoom lens 3 according to Example 3 at the wide-angle end when focused on infinity. FIG. 29 shows longitudinal aberration of the zoom lens 3 according to Example 3 at an intermediate position when focused on infinity. FIG. 30 shows longitudinal aberration of the zoom lens 3 according to Example 3 at the telephoto end when focused on infinity. FIG. 31 shows longitudinal aberration of the zoom lens 3 according to Example 3 at the wide-angle end when focused on a close distance. FIG. 32 shows longitudinal aberration of the zoom lens 3 according to Example 3 at an intermediate position when focused on a close distance. FIG. 33 shows longitudinal aberration of the zoom lens 3 according to Example 3 at the telephoto end when focused on a close distance. FIG. 34 shows lateral aberration of the zoom lens 3 according to Example 3 at the wide-angle end when focused on infinity. FIG. 35 shows lateral aberration of the zoom lens 3 according to Example 3 at an intermediate position when focused on infinity. FIG. 36 shows lateral aberration of the zoom lens 3 according to Example 3 at the telephoto end when focused on infinity. Fig. 37 shows the lateral aberration of the zoom lens 3 according to Example 3 at the wide-angle end and when focusing on a close distance. Fig. 38 shows the lateral aberration of the zoom lens 3 according to Example 3 at the intermediate position and when focusing on a close distance. Fig. 39 shows the lateral aberration of the zoom lens 3 according to Example 3 at the telephoto end and when focusing on a close distance.

[0141] As can be seen from each aberration diagram, the zoom lens 3 according to Example 3 has excellent correction of various aberrations and has excellent imaging performance.

[0142] Example 4 Table 16 shows basic lens data for the zoom lens 4 according to Example 4 shown in FIG. 40 . Table 17 shows values ​​for the focal length f of the entire system, the F-number, the total angle of view 2ω, the image height Y, and the total optical length L of the zoom lens 4 according to Example 4. Table 18 shows data on surface separations that are variable during zooming and focusing in the zoom lens 4 according to Example 4. Table 18 also shows values ​​for the magnification β of the zoom lens 4 according to Example 4. Table 17 shows values ​​for the wide-angle end (Wide), the middle position (Mid), and the telephoto end (Tele) when the object distance (d0) is infinity. Table 18 shows values ​​for the wide-angle end (Wide), the middle position (Mid), and the telephoto end (Tele) when the object distance (d0) is infinity and when the object distance is close. Table 19 shows the values ​​of coefficients representing the shape of the aspherical surface in the zoom lens 4 according to Example 4. Table 20 shows the first surface and focal length (unit: mm) of each lens group in the zoom lens 4 according to Example 4.

[0143] The zoom lens 4 according to Example 4 has a configuration in which the first lens group Gr1 to the seventh lens group Gr7 are arranged in this order from the object side to the image plane side. An aperture stop St is arranged on the object side of the third lens group Gr3. The third lens group Gr3 and the fourth lens group Gr4 form the intermediate lens group Grm. The fifth lens group Gr5 to the seventh lens group Gr7 form the rear lens group Grr. Note that, for example, a flare cutter whose diameter changes during zooming may be arranged on the object side of the fourth lens group Gr4 (surface No. 21) in order to improve peripheral optical performance.

[0144] The first lens group Gr1 has positive refractive power. The first lens group Gr1 is composed of, in order from the object side to the image plane side, lenses L11 to L13. The lens L11 corresponds to the lens L1i that satisfies the above conditional expression (5). The lens L11 corresponds to the negative lens L1n that satisfies the above conditional expression (8). The lens L12 corresponds to the positive lens L1p that satisfies the above conditional expression (7).

[0145] The second lens group Gr2 has negative refractive power and is composed of, in order from the object side to the image plane side, lenses L21 to L25. The lens L24 corresponds to the positive lens L2p that satisfies the above conditional expression (6).

[0146] The third lens group Gr3 has positive refractive power. The third lens group Gr3 is composed of, in order from the object side to the image plane side, lenses L31 to L33. The lens L31 corresponds to the positive lens Lmp_asp having an aspherical surface. The lens L32 corresponds to the positive lens Lmp that satisfies the above conditional expression (9).

[0147] The fourth lens group Gr4 has positive refractive power and is composed of, in order from the object side to the image plane side, lenses L41 to L45. The lens L43 corresponds to the positive lens Lmp that satisfies the above conditional expression (9).

[0148] The fifth lens group Gr5 has negative refractive power and is made up of a lens L51. The fifth lens group Gr5 is a focus lens group that corresponds to the negative lens group Grrn in the rear lens group Grr.

[0149] The sixth lens group Gr6 has positive refractive power and is made up of a lens L61. The sixth lens group Gr6 is a focus lens group that corresponds to the positive lens group Grrp in the rear lens group Grr.

[0150] The seventh lens group Gr7 has negative refractive power and is composed of, in order from the object side to the image plane side, a lens L71 and a lens L72. The lens L72 corresponds to the lens Lrr that satisfies the above conditional expression (10).

[0151] During zooming from the wide-angle end to the telephoto end, the first lens group Gr1 moves toward the object side relative to the image plane IMG, and each of the first to sixth lens groups Gr1 to Gr6 moves so that the spacing between adjacent lens groups changes.

[0152] When the object distance changes from infinity to a close distance, focusing is performed by the fifth lens group Gr5 and the sixth lens group Gr6 moving in the optical axis direction along different trajectories, and when the object distance changes from infinity to a close distance, focusing is performed by the fifth lens group Gr5 moving toward the image plane.

[0153] The above configuration realizes a zoom lens that is small and lightweight, yet has a large aperture and high optical performance, suppresses performance fluctuations due to shooting distance, and achieves a high maximum shooting magnification.

[0154]

[0155]

[0156]

[0157]

[0158]

[0159] FIG. 41 shows longitudinal aberration of the zoom lens 4 according to Example 4 at the wide-angle end when focused at infinity. FIG. 42 shows longitudinal aberration of the zoom lens 4 according to Example 4 at an intermediate position when focused at infinity. FIG. 43 shows longitudinal aberration of the zoom lens 4 according to Example 4 at the telephoto end when focused at infinity. FIG. 44 shows longitudinal aberration of the zoom lens 4 according to Example 4 at the wide-angle end when focused at a close distance. FIG. 45 shows longitudinal aberration of the zoom lens 4 according to Example 4 at an intermediate position when focused at a close distance. FIG. 46 shows longitudinal aberration of the zoom lens 4 according to Example 4 at the telephoto end when focused at a close distance. FIG. 47 shows lateral aberration of the zoom lens 4 according to Example 4 at the wide-angle end when focused at infinity. FIG. 48 shows lateral aberration of the zoom lens 4 according to Example 4 at an intermediate position when focused at infinity. FIG. 49 shows lateral aberration of the zoom lens 4 according to Example 4 at the telephoto end when focused at infinity. Fig. 50 shows the lateral aberration of the zoom lens 4 according to Example 4 at the wide-angle end and when focusing on a close distance. Fig. 51 shows the lateral aberration of the zoom lens 4 according to Example 4 at the intermediate position and when focusing on a close distance. Fig. 52 shows the lateral aberration of the zoom lens 4 according to Example 4 at the telephoto end and when focusing on a close distance.

[0160] As can be seen from each aberration diagram, the zoom lens 4 according to Example 4 has excellent correction of various aberrations and has excellent imaging performance.

[0161] [Example 5] Table 21 shows basic lens data for the zoom lens 5 according to Example 5 shown in FIG. 53 . Table 22 shows values ​​for the focal length f, F-number, total angle of view 2ω, image height Y, and total optical length L of the entire system for the zoom lens 5 according to Example 5. Table 23 shows data on surface separations that are variable during zooming and focusing for the zoom lens 5 according to Example 5. Table 23 also shows values ​​for the magnification β of the zoom lens 5 according to Example 5. Table 22 shows values ​​for the wide-angle end (Wide), the middle position (Mid), and the telephoto end (Tele) when the object distance (d0) is infinity. Table 23 shows values ​​for the wide-angle end (Wide), the middle position (Mid), and the telephoto end (Tele) when the object distance (d0) is infinity and when the object distance is close. Table 24 shows the values ​​of coefficients representing the shape of the aspherical surface in the zoom lens 5 according to Example 5. Table 25 shows the initial surface and focal length (unit: mm) of each lens group in the zoom lens 5 according to Example 5.

[0162] The zoom lens 5 according to Example 5 has a configuration in which the first lens group Gr1 to the seventh lens group Gr7 are arranged in this order from the object side to the image plane side. The aperture stop St is arranged on the object side of the third lens group Gr3. The third lens group Gr3 and the fourth lens group Gr4 form the intermediate lens group Grm. The fifth lens group Gr5 to the seventh lens group Gr7 form the rear lens group Grr. Note that, for example, a flare cutter whose diameter changes during zooming may be arranged on the object side of the fourth lens group Gr4 (surface No. 21) in order to improve peripheral optical performance.

[0163] The first lens group Gr1 has positive refractive power. The first lens group Gr1 is composed of, in order from the object side to the image plane side, lenses L11 to L13. The lens L11 corresponds to the lens L1i that satisfies the above conditional expression (5). The lens L11 corresponds to the negative lens L1n that satisfies the above conditional expression (8). The lens L12 corresponds to the positive lens L1p that satisfies the above conditional expression (7).

[0164] The second lens group Gr2 has negative refractive power and is composed of, in order from the object side to the image plane side, lenses L21 to L25. The lens L24 corresponds to the positive lens L2p that satisfies the above conditional expression (6).

[0165] The third lens group Gr3 has positive refractive power. The third lens group Gr3 is composed of, in order from the object side to the image plane side, lenses L31 to L33. The lens L31 corresponds to the positive lens Lmp_asp having an aspherical surface. The lens L32 corresponds to the positive lens Lmp that satisfies the above conditional expression (9).

[0166] The fourth lens group Gr4 has positive refractive power and is composed of, in order from the object side to the image plane side, lenses L41 to L45. The lens L43 corresponds to the positive lens Lmp that satisfies the above conditional expression (9).

[0167] The fifth lens group Gr5 has negative refractive power and is made up of a lens L51. The fifth lens group Gr5 is a focus lens group that corresponds to the negative lens group Grrn in the rear lens group Grr.

[0168] The sixth lens group Gr6 has positive refractive power and is made up of a lens L61. The sixth lens group Gr6 is a focus lens group that corresponds to the positive lens group Grrp in the rear lens group Grr.

[0169] The seventh lens group Gr7 has negative refractive power and is composed of, in order from the object side to the image plane side, a lens L71 and a lens L72. The lens L72 corresponds to the lens Lrr that satisfies the above conditional expression (10).

[0170] During zooming from the wide-angle end to the telephoto end, the first lens group Gr1 moves toward the object side relative to the image plane IMG, and each of the first to sixth lens groups Gr1 to Gr6 moves so that the spacing between adjacent lens groups changes.

[0171] When the object distance changes from infinity to a close distance, focusing is performed by the fifth lens group Gr5 and the sixth lens group Gr6 moving in the optical axis direction along different trajectories, and when the object distance changes from infinity to a close distance, focusing is performed by the fifth lens group Gr5 moving toward the image plane.

[0172] The above configuration realizes a zoom lens that is small and lightweight, yet has a large aperture and high optical performance, suppresses performance fluctuations due to shooting distance, and achieves a high maximum shooting magnification.

[0173]

[0174]

[0175]

[0176]

[0177]

[0178] FIG. 54 shows longitudinal aberration of the zoom lens 5 according to Example 5 at the wide-angle end when focused at infinity. FIG. 55 shows longitudinal aberration of the zoom lens 5 according to Example 5 at an intermediate position when focused at infinity. FIG. 56 shows longitudinal aberration of the zoom lens 5 according to Example 5 at the telephoto end when focused at infinity. FIG. 57 shows longitudinal aberration of the zoom lens 5 according to Example 5 at the wide-angle end when focused at a close distance. FIG. 58 shows longitudinal aberration of the zoom lens 5 according to Example 5 at an intermediate position when focused at a close distance. FIG. 59 shows longitudinal aberration of the zoom lens 5 according to Example 5 at the telephoto end when focused at a close distance. FIG. 60 shows lateral aberration of the zoom lens 5 according to Example 5 at the wide-angle end when focused at infinity. FIG. 61 shows lateral aberration of the zoom lens 5 according to Example 5 at an intermediate position when focused at infinity. FIG. 62 shows lateral aberration of the zoom lens 5 according to Example 5 at the telephoto end when focused at infinity. Fig. 63 shows the lateral aberration of the zoom lens 5 according to Example 5 at the wide-angle end and when focusing on a close distance. Fig. 64 shows the lateral aberration of the zoom lens 5 according to Example 5 at the intermediate position and when focusing on a close distance. Fig. 65 shows the lateral aberration of the zoom lens 5 according to Example 5 at the telephoto end and when focusing on a close distance.

[0179] As can be seen from each aberration diagram, the zoom lens 5 according to Example 5 has excellent correction of various aberrations and has excellent imaging performance.

[0180] [Example 6] Table 26 shows basic lens data for the zoom lens 6 according to Example 6 shown in FIG. 66 . Table 27 shows values ​​for the focal length f of the entire system, the F-number, the total angle of view 2ω, the image height Y, and the total optical length L of the zoom lens 6 according to Example 6. Table 28 shows data on surface separations that are variable during zooming and focusing in the zoom lens 6 according to Example 6. Table 28 also shows values ​​for the magnification β of the zoom lens 6 according to Example 6. Table 27 shows values ​​for the wide-angle end (Wide), the middle position (Mid), and the telephoto end (Tele) when the object distance (d0) is infinity. Table 28 shows values ​​for the wide-angle end (Wide), the middle position (Mid), and the telephoto end (Tele) when the object distance (d0) is infinity and when the object distance is close. Table 29 shows the values ​​of coefficients representing the shape of the aspherical surface in the zoom lens 6 according to Example 6. Table 30 shows the first surface and focal length (unit: mm) of each lens group in the zoom lens 6 according to Example 6.

[0181] The zoom lens 6 according to Example 6 is configured such that the first to fifth lens groups Gr1 to Gr5 are arranged in this order from the object side to the image plane side. The aperture stop St is arranged on the object side of the third lens group Gr3. The third lens group Gr3 constitutes the middle lens group Grm. The fourth lens group Gr4 and the fifth lens group Gr5 constitute the rear lens group Grr.

[0182] The first lens group Gr1 has positive refractive power. The first lens group Gr1 is composed of, in order from the object side to the image plane side, lenses L11 to L13. The lens L11 corresponds to the lens L1i that satisfies the above conditional expression (5). The lens L11 corresponds to the negative lens L1n that satisfies the above conditional expression (8). The lens L12 corresponds to the positive lens L1p that satisfies the above conditional expression (7).

[0183] The second lens group Gr2 has negative refractive power and is composed of, in order from the object side to the image plane side, lenses L21 to L25. The lens L24 corresponds to the positive lens L2p that satisfies the above conditional expression (6).

[0184] The third lens group Gr3 has positive refractive power. The third lens group Gr3 is composed of, in order from the object side to the image plane side, lenses L31 to L38. The lens L32 corresponds to the positive lens Lmp_asp having an aspherical surface. The lens L36 corresponds to the positive lens Lmp that satisfies the above conditional expression (9).

[0185] The fourth lens group Gr4 has negative refractive power and is made up of a lens L41. The fourth lens group Gr4 is a focus lens group that corresponds to the negative lens group Grrn in the rear lens group Grr.

[0186] The fifth lens group Gr5 has positive refractive power and is made up of a lens L51. The fifth lens group Gr5 is a focus lens group that corresponds to the positive lens group Grrp in the rear lens group Grr.

[0187] During zooming from the wide-angle end to the telephoto end, the first lens group Gr1 moves toward the object side relative to the image plane IMG, and each of the first lens group Gr1 to the fifth lens group Gr5 moves so that the spacing between adjacent lens groups changes.

[0188] When the object distance changes from infinity to a close distance, focusing is performed by the fourth lens group Gr4 and the fifth lens group Gr5 moving along different trajectories in the optical axis direction, and when the object distance changes from infinity to a close distance, focusing is performed by the fourth lens group Gr4 moving toward the image plane.

[0189] The above configuration realizes a zoom lens that is small and lightweight, yet has a large aperture and high optical performance, suppresses performance fluctuations due to shooting distance, and achieves a high maximum shooting magnification.

[0190]

[0191]

[0192]

[0193]

[0194]

[0195] FIG. 67 shows longitudinal aberration of the zoom lens 6 according to Example 6 at the wide-angle end when focused at infinity. FIG. 68 shows longitudinal aberration of the zoom lens 6 according to Example 6 at an intermediate position when focused at infinity. FIG. 69 shows longitudinal aberration of the zoom lens 6 according to Example 6 at the telephoto end when focused at infinity. FIG. 70 shows longitudinal aberration of the zoom lens 6 according to Example 6 at the wide-angle end when focused at a close distance. FIG. 71 shows longitudinal aberration of the zoom lens 6 according to Example 6 at an intermediate position when focused at a close distance. FIG. 72 shows longitudinal aberration of the zoom lens 6 according to Example 6 at the telephoto end when focused at a close distance. FIG. 73 shows lateral aberration of the zoom lens 6 according to Example 6 at the wide-angle end when focused at infinity. FIG. 74 shows lateral aberration of the zoom lens 6 according to Example 6 at an intermediate position when focused at infinity. FIG. 75 shows lateral aberration of the zoom lens 6 according to Example 6 at the telephoto end when focused at infinity. Fig. 76 shows the lateral aberration of the zoom lens 6 according to Example 6 at the wide-angle end and when focusing on a close distance. Fig. 77 shows the lateral aberration of the zoom lens 6 according to Example 6 at the intermediate position and when focusing on a close distance. Fig. 78 shows the lateral aberration of the zoom lens 6 according to Example 6 at the telephoto end and when focusing on a close distance.

[0196] As can be seen from each aberration diagram, the zoom lens 6 according to Example 6 has excellent correction of various aberrations and has excellent imaging performance.

[0197] [Other Numerical Data for Each Example] [Tables 31] to [Table 34] show the values ​​for each of the above-mentioned conditional expressions, etc., summarized for each example. As can be seen from [Tables 31] to [Table 34], the values ​​for each example fall within the corresponding numerical range for each conditional expression.

[0198]

[0199]

[0200]

[0201]

[0202] 5. Application Examples 5.1 First Application Example The technology according to the present disclosure can be applied to various products. For example, the technology according to the present disclosure may be realized as a device mounted on any type of moving body, such as an automobile, an electric vehicle, a hybrid electric vehicle, a motorcycle, a bicycle, personal mobility, an airplane, a drone, a ship, a robot, construction machinery, or agricultural machinery (tractor).

[0203] 80 is a block diagram showing a schematic configuration example of a vehicle control system 7000, which is an example of a mobile object control system to which the technology according to the present disclosure can be applied. The vehicle control system 7000 includes a plurality of electronic control units connected via a communication network 7010. In the example shown in FIG. 80 , the vehicle control system 7000 includes a drive system control unit 7100, a body system control unit 7200, a battery control unit 7300, an outside-vehicle information detection unit 7400, an inside-vehicle information detection unit 7500, and an integrated control unit 7600. The communication network 7010 connecting these multiple control units may be an in-vehicle communication network conforming to any standard, such as a Controller Area Network (CAN), a Local Interconnect Network (LIN), a Local Area Network (LAN), or FlexRay (registered trademark).

[0204] Each control unit includes a microcomputer that performs arithmetic processing according to various programs, a memory unit that stores the programs executed by the microcomputer or parameters used in various calculations, and a drive circuit that drives various controlled devices. Each control unit includes a network I / F for communicating with other control units via a communication network 7010, and a communication I / F for communicating with devices or sensors inside and outside the vehicle via wired or wireless communication. Figure 80 illustrates the functional configuration of the integrated control unit 7600, including a microcomputer 7610, a general-purpose communication I / F 7620, a dedicated communication I / F 7630, a positioning unit 7640, a beacon receiving unit 7650, an in-vehicle device I / F 7660, an audio / video output unit 7670, an in-vehicle network I / F 7680, and a memory unit 7690. The other control units also include a microcomputer, a communication I / F, a memory unit, and the like.

[0205] The drivetrain control unit 7100 controls the operation of devices related to the drivetrain of the vehicle in accordance with various programs. For example, the drivetrain control unit 7100 functions as a control device for a drive force generating device for generating drive force for the vehicle, such as an internal combustion engine or a drive motor, a drive force transmission mechanism for transmitting drive force to the wheels, a steering mechanism for adjusting the steering angle of the vehicle, and a braking device for generating braking force for the vehicle. The drivetrain control unit 7100 may also function as a control device for an ABS (Antilock Brake System) or an ESC (Electronic Stability Control), etc.

[0206] A vehicle state detection unit 7110 is connected to the drivetrain control unit 7100. The vehicle state detection unit 7110 includes at least one of a gyro sensor that detects the angular velocity of the axial rotational motion of the vehicle body, an acceleration sensor that detects the acceleration of the vehicle, or a sensor that detects the amount of operation of the accelerator pedal, the amount of operation of the brake pedal, the steering angle of the steering wheel, the engine rotation speed, the rotation speed of the wheels, etc. The drivetrain control unit 7100 performs arithmetic processing using signals input from the vehicle state detection unit 7110, and controls the internal combustion engine, the drive motor, the electric power steering device, the brake device, etc.

[0207] The body system control unit 7200 controls the operation of various devices equipped in the vehicle body according to various programs. For example, the body system control unit 7200 functions as a control device for a keyless entry system, a smart key system, a power window device, or various lamps such as headlamps, backup lamps, brake lamps, turn signals, and fog lamps. In this case, radio waves transmitted from a portable device that serves as a key or signals from various switches can be input to the body system control unit 7200. The body system control unit 7200 receives these radio waves or signals and controls the vehicle's door lock device, power window device, lamps, etc.

[0208] The battery control unit 7300 controls the secondary battery 7310, which is the power supply source for the drive motor, in accordance with various programs. For example, information such as battery temperature, battery output voltage, or remaining battery capacity is input to the battery control unit 7300 from a battery device equipped with the secondary battery 7310. The battery control unit 7300 performs arithmetic processing using these signals, and controls the temperature regulation of the secondary battery 7310 or a cooling device or the like equipped in the battery device.

[0209] The outside vehicle information detection unit 7400 detects information outside the vehicle equipped with the vehicle control system 7000. For example, at least one of an imaging unit 7410 and an outside vehicle information detection unit 7420 is connected to the outside vehicle information detection unit 7400. The imaging unit 7410 includes at least one of a time-of-flight (ToF) camera, a stereo camera, a monocular camera, an infrared camera, and other cameras. The outside vehicle information detection unit 7420 includes at least one of an environmental sensor for detecting the current weather or climate, or a surrounding information detection sensor for detecting other vehicles, obstacles, pedestrians, etc. around the vehicle equipped with the vehicle control system 7000.

[0210] The environmental sensor may be, for example, at least one of a raindrop sensor that detects rain, a fog sensor that detects fog, a sunshine sensor that detects the degree of sunshine, and a snow sensor that detects snowfall. The surrounding information detection sensor may be at least one of an ultrasonic sensor, a radar device, and a LIDAR (Light Detection and Ranging, Laser Imaging Detection and Ranging) device. The imaging unit 7410 and the outside vehicle information detection unit 7420 may each be provided as an independent sensor or device, or may be provided as a device in which multiple sensors or devices are integrated.

[0211] Here, Figure 81 shows an example of the installation positions of the imaging unit 7410 and the vehicle exterior information detection unit 7420. The imaging units 7910, 7912, 7914, 7916, and 7918 are provided, for example, at least one of the front nose, side mirrors, rear bumper, back door, and upper part of the windshield inside the vehicle cabin of the vehicle 7900. The imaging unit 7910 provided on the front nose and the imaging unit 7918 provided on the upper part of the windshield inside the vehicle cabin mainly acquire images of the front of the vehicle 7900. The imaging units 7912 and 7914 provided on the side mirrors mainly acquire images of the sides of the vehicle 7900. The imaging unit 7916 provided on the rear bumper or back door mainly acquires images of the rear of the vehicle 7900. The imaging unit 7918 provided on the upper part of the windshield inside the vehicle cabin is mainly used to detect leading vehicles, pedestrians, obstacles, traffic lights, traffic signs, lanes, etc.

[0212] 81 shows an example of the imaging ranges of the imaging units 7910, 7912, 7914, and 7916. Imaging range a indicates the imaging range of the imaging unit 7910 provided on the front nose, imaging ranges b and c indicate the imaging ranges of the imaging units 7912 and 7914 provided on the side mirrors, respectively, and imaging range d indicates the imaging range of the imaging unit 7916 provided on the rear bumper or back door. For example, by overlaying the image data captured by the imaging units 7910, 7912, 7914, and 7916, a bird's-eye view image of the vehicle 7900 viewed from above can be obtained.

[0213] The outside vehicle information detection units 7920, 7922, 7924, 7926, 7928, and 7930 provided on the front, rear, sides, corners, and above the windshield inside the vehicle cabin of the vehicle 7900 may be, for example, ultrasonic sensors or radar devices. The outside vehicle information detection units 7920, 7926, and 7930 provided on the front nose, rear bumper, back door, and above the windshield inside the vehicle cabin of the vehicle 7900 may be, for example, LIDAR devices. These outside vehicle information detection units 7920 to 7930 are mainly used to detect preceding vehicles, pedestrians, obstacles, etc.

[0214] Returning to FIG. 80 , the explanation will be continued. The outside vehicle information detection unit 7400 causes the imaging unit 7410 to capture an image outside the vehicle and receives the captured image data. The outside vehicle information detection unit 7400 also receives detection information from the connected outside vehicle information detection unit 7420. If the outside vehicle information detection unit 7420 is an ultrasonic sensor, a radar device, or a LIDAR device, the outside vehicle information detection unit 7400 emits ultrasonic waves or electromagnetic waves and receives information on the received reflected waves. Based on the received information, the outside vehicle information detection unit 7400 may perform object detection processing or distance detection processing for people, vehicles, obstacles, signs, text on the road, etc. Based on the received information, the outside vehicle information detection unit 7400 may also perform environmental recognition processing for recognizing rainfall, fog, road conditions, etc. Based on the received information, the outside vehicle information detection unit 7400 may also calculate the distance to an object outside the vehicle.

[0215] The outside vehicle information detection unit 7400 may also perform image recognition processing or distance detection processing to recognize people, vehicles, obstacles, signs, or characters on the road surface based on the received image data. The outside vehicle information detection unit 7400 may perform processing such as distortion correction or alignment on the received image data, and may also generate an overhead image or a panoramic image by combining image data captured by different image capturing units 7410. The outside vehicle information detection unit 7400 may also perform viewpoint conversion processing using image data captured by different image capturing units 7410.

[0216] The interior information detection unit 7500 detects information inside the vehicle. A driver state detection unit 7510 that detects the driver's state is connected to the interior information detection unit 7500, for example. The driver state detection unit 7510 may include a camera that captures an image of the driver, a biosensor that detects the driver's biometric information, or a microphone that collects sound from within the vehicle cabin. The biosensor is provided, for example, on the seat or steering wheel, and detects the biometric information of a passenger sitting in the seat or the driver gripping the steering wheel. The interior information detection unit 7500 may calculate the driver's level of fatigue or concentration based on the detection information input from the driver state detection unit 7510, or may determine whether the driver is dozing off. The interior information detection unit 7500 may perform processing such as noise canceling on the collected audio signal.

[0217] The integrated control unit 7600 controls the overall operation of the vehicle control system 7000 according to various programs. An input unit 7800 is connected to the integrated control unit 7600. The input unit 7800 may be implemented by a device that can be operated by a passenger, such as a touch panel, a button, a microphone, a switch, or a lever. Data obtained by voice recognition of a voice input through a microphone may be input to the integrated control unit 7600. The input unit 7800 may be, for example, a remote control device using infrared or other radio waves, or an externally connected device such as a mobile phone or a personal digital assistant (PDA) that can operate the vehicle control system 7000. The input unit 7800 may be, for example, a camera, in which case the passenger can input information using gestures. Alternatively, data obtained by detecting the movement of a wearable device worn by the passenger may be input. Furthermore, the input unit 7800 may include, for example, an input control circuit that generates an input signal based on information input by the passenger using the input unit 7800 and outputs the input signal to the integrated control unit 7600. Passengers and the like operate this input unit 7800 to input various data to the vehicle control system 7000 and to instruct processing operations.

[0218] The storage unit 7690 may include a ROM (Read Only Memory) that stores various programs executed by the microcomputer, and a RAM (Random Access Memory) that stores various parameters, calculation results, sensor values, etc. The storage unit 7690 may also be realized by a magnetic storage device such as an HDD (Hard Disc Drive), a semiconductor storage device, an optical storage device, a magneto-optical storage device, or the like.

[0219] The general-purpose communication I / F 7620 is a general-purpose communication I / F that mediates communication with various devices present in the external environment 7750. The general-purpose communication I / F 7620 may implement a cellular communication protocol such as GSM (Global System of Mobile communications), WiMAX (registered trademark), LTE (Long Term Evolution), or LTE-Advanced (LTE-A), or other wireless communication protocols such as a wireless LAN (also referred to as Wi-Fi (registered trademark)) or Bluetooth (registered trademark). The general-purpose communication I / F 7620 may connect to a device (e.g., an application server or a control server) present on an external network (e.g., the Internet, a cloud network, or an operator-specific network) via, for example, a base station or an access point. In addition, the general-purpose communication I / F 7620 may connect to a terminal located near the vehicle (for example, a terminal of a driver, pedestrian, or store, or an MTC (Machine Type Communication) terminal) using, for example, P2P (Peer To Peer) technology.

[0220] The dedicated communication I / F 7630 is a communication I / F that supports a communication protocol designed for use in vehicles. The dedicated communication I / F 7630 may implement a standard protocol such as WAVE (Wireless Access in Vehicle Environment), which is a combination of a lower layer IEEE 802.11p and an upper layer IEEE 1609, DSRC (Dedicated Short Range Communications), or a cellular communication protocol. The dedicated communication I / F 7630 typically performs V2X communication, which is a concept including one or more of vehicle-to-vehicle communication, vehicle-to-infrastructure communication, vehicle-to-home communication, and vehicle-to-pedestrian communication.

[0221] The positioning unit 7640 performs positioning by receiving, for example, GNSS signals from GNSS (Global Navigation Satellite System) satellites (for example, GPS signals from GPS (Global Positioning System) satellites), and generates position information including the latitude, longitude, and altitude of the vehicle. Note that the positioning unit 7640 may identify the current position by exchanging signals with a wireless access point, or may obtain position information from a terminal such as a mobile phone, PHS, or smartphone that has a positioning function.

[0222] The beacon receiving unit 7650 receives, for example, radio waves or electromagnetic waves transmitted from radio stations or the like installed on the road, and acquires information such as the current location, congestion, road closures, required travel time, etc. The function of the beacon receiving unit 7650 may be included in the dedicated communication I / F 7630 described above.

[0223] The in-vehicle device I / F 7660 is a communication interface that mediates connections between the microcomputer 7610 and various in-vehicle devices 7760 present in the vehicle. The in-vehicle device I / F 7660 may establish a wireless connection using a wireless communication protocol such as a wireless LAN, Bluetooth (registered trademark), NFC (Near Field Communication), or WUSB (Wireless USB). The in-vehicle device I / F 7660 may also establish a wired connection via a connection terminal (and, if necessary, a cable) not shown, such as a Universal Serial Bus (USB), a High-Definition Multimedia Interface (HDMI (registered trademark), or an MHL (Mobile High-Definition Link)). The in-vehicle device 7760 may include, for example, at least one of a mobile device or wearable device owned by a passenger, or an information device carried or installed in the vehicle. The in-vehicle device 7760 may also include a navigation device that searches for a route to a desired destination. The in-vehicle device I / F 7660 exchanges control signals or data signals with these in-vehicle devices 7760 .

[0224] The in-vehicle network I / F 7680 is an interface that mediates communication between the microcomputer 7610 and the communication network 7010. The in-vehicle network I / F 7680 transmits and receives signals in accordance with a predetermined protocol supported by the communication network 7010.

[0225] The microcomputer 7610 of the integrated control unit 7600 controls the vehicle control system 7000 in accordance with various programs based on information acquired via at least one of the general-purpose communication I / F 7620, the dedicated communication I / F 7630, the positioning unit 7640, the beacon receiving unit 7650, the in-vehicle device I / F 7660, and the in-vehicle network I / F 7680. For example, the microcomputer 7610 may calculate control target values ​​for the driving force generating device, the steering mechanism, or the braking device based on the acquired information inside and outside the vehicle, and output control commands to the drivetrain control unit 7100. For example, the microcomputer 7610 may perform cooperative control aimed at realizing functions of an Advanced Driver Assistance System (ADAS), including vehicle collision avoidance or impact mitigation, following driving based on the following distance, vehicle speed maintenance driving, vehicle collision warning, vehicle lane departure warning, etc. In addition, the microcomputer 7610 may perform cooperative control for the purpose of autonomous driving, in which the vehicle travels autonomously without relying on driver operation, by controlling a driving force generating device, steering mechanism, braking device, etc. based on information acquired about the vehicle's surroundings.

[0226] The microcomputer 7610 may generate three-dimensional distance information between the vehicle and objects such as surrounding structures and people, and create local map information including information about the vicinity of the vehicle's current location, based on information acquired via at least one of the general-purpose communication I / F 7620, the dedicated communication I / F 7630, the positioning unit 7640, the beacon receiving unit 7650, the in-vehicle device I / F 7660, and the in-vehicle network I / F 7680. Furthermore, the microcomputer 7610 may predict dangers, such as a vehicle collision, the approach of a pedestrian, or entry into a closed road, based on the acquired information, and generate a warning signal. The warning signal may be, for example, a signal for generating a warning sound or turning on a warning lamp.

[0227] The audio / image output unit 7670 transmits at least one audio and / or image output signal to an output device capable of visually or audibly notifying vehicle occupants or the outside of the vehicle of information. In the example of FIG. 80 , an audio speaker 7710, a display unit 7720, and an instrument panel 7730 are illustrated as output devices. The display unit 7720 may include, for example, at least one of an on-board display and a head-up display. The display unit 7720 may have an AR (Augmented Reality) display function. The output device may also be other devices, such as headphones, a wearable device such as an eyeglass-type display worn by the occupant, a projector, or a lamp. When the output device is a display device, the display device visually displays results obtained by various processes performed by the microcomputer 7610 or information received from other control units in various formats, such as text, images, tables, and graphs. When the output device is an audio output device, the audio output device converts audio signals, such as reproduced audio data or acoustic data, into analog signals and audibly outputs the analog signals.

[0228] In the example shown in FIG. 80 , at least two control units connected via the communication network 7010 may be integrated into a single control unit. Alternatively, each control unit may be composed of multiple control units. Furthermore, the vehicle control system 7000 may include another control unit not shown. In the above description, some or all of the functions performed by one of the control units may be assigned to another control unit. In other words, as long as information is transmitted and received via the communication network 7010, predetermined arithmetic processing may be performed by one of the control units. Similarly, a sensor or device connected to one of the control units may be connected to another control unit, and multiple control units may transmit and receive detection information to each other via the communication network 7010.

[0229] In the vehicle control system 7000 described above, the zoom lens and imaging device of the present disclosure can be applied to the imaging unit 7410 and the imaging units 7910, 7912, 7914, 7916, and 7918.

[0230] 5.2 Second Application Example The technology according to the present disclosure can be applied to a medical imaging system, which is a medical system that uses imaging technology, such as an endoscope system or a microscope system.

[0231] [Endoscopic System] An example of an endoscope system will be described with reference to Figs. 82 and 83 . Fig. 82 is a diagram illustrating an example of the schematic configuration of an endoscope system 5000 to which the technology according to the present disclosure can be applied. Fig. 83 is a diagram illustrating an example of the configuration of an endoscope 5001 and a CCU (Camera Control Unit) 5039. Fig. 82 illustrates a state in which an operator (e.g., a doctor) 5067, who is a surgical participant, is performing surgery on a patient 5071 on a patient bed 5069 using the endoscope system 5000. As shown in Fig. 82 , the endoscope system 5000 includes an endoscope 5001, which is a medical imaging device, a CCU 5039, a light source device 5043, a recording device 5053, an output device 5055, and a support device 5027 that supports the endoscope 5001.

[0232] In endoscopic surgery, an insertion aid called a trocar 5025 is inserted into a patient 5071. Then, a scope 5003 and surgical tools 5021 connected to an endoscope 5001 are inserted into the body of the patient 5071 via the trocar 5025. The surgical tools 5021 are, for example, energy devices such as an electric scalpel, forceps, etc.

[0233] A surgical image, which is a medical image showing the inside of the body of a patient 5071 photographed by an endoscope 5001, is displayed on a display device 5041. An operator 5067 performs a procedure on the surgical target using a surgical tool 5021 while viewing the surgical image displayed on the display device 5041. Note that the medical image is not limited to a surgical image, and may be a diagnostic image photographed during a diagnosis.

[0234] [Endoscope] The endoscope 5001 is an imaging unit that captures images of the inside of the patient's 5071. For example, as shown in FIG. 83 , the endoscope 5001 is a camera 5005 that includes a focusing optical system 50051 that focuses incident light, a zoom optical system 50052 that changes the focal length of the imaging unit to enable optical zoom, a focus optical system 50053 that changes the focal length of the imaging unit to enable focus adjustment, and a light-receiving element 50054. The endoscope 5001 generates pixel signals by focusing light onto the light-receiving element 50054 via a connected scope 5003, and outputs the pixel signals to the CCU 5039 via a transmission system. The scope 5003 has an objective lens at its tip and is an insertion section that guides light from a connected light source device 5043 into the inside of the patient's 5071. The scope 5003 is, for example, a rigid scope for rigid endoscopes or a flexible scope for flexible endoscopes. The scope 5003 may be a direct-view endoscope or an oblique-view endoscope. Furthermore, the pixel signal may be a signal based on a signal output from a pixel, such as a RAW signal or an image signal. Furthermore, a configuration may be adopted in which a memory is installed in the transmission system connecting the endoscope 5001 and the CCU 5039, and parameters related to the endoscope 5001 and the CCU 5039 are stored in the memory. The memory may be located, for example, in a connection portion of the transmission system or on a cable. For example, parameters at the time of shipment of the endoscope 5001 and parameters that change when power is applied may be stored in the memory of the transmission system, and the operation of the endoscope may be changed based on parameters read from the memory. Furthermore, the endoscope and the transmission system may be collectively referred to as an endoscope. The light-receiving element 50054 is a sensor that converts received light into a pixel signal, and is, for example, a CMOS (Complementary Metal Oxide Semiconductor) type image sensor. It is preferable that the light-receiving element 50054 be an image sensor capable of color imaging with a Bayer array. Furthermore, the light receiving element 50054 is preferably an imaging element having a number of pixels corresponding to a resolution of, for example, 4K (3840 horizontal pixels × 2160 vertical pixels), 8K (7680 horizontal pixels × 4320 vertical pixels), or square 4K (3840 or more horizontal pixels × 3840 or more vertical pixels). The light receiving element 50054 may be a single sensor chip or multiple sensor chips.For example, a prism may be provided to separate incident light into predetermined wavelength bands, and each wavelength band may be imaged by a different light-receiving element. Alternatively, multiple light-receiving elements may be provided for stereoscopic vision. The light-receiving element 50054 may be a sensor including an image processing circuit within its chip structure, or a Time of Flight (ToF) sensor. The transmission system may be, for example, an optical fiber cable or wireless transmission. Wireless transmission may be performed via any means capable of transmitting pixel signals generated by the endoscope 5001. For example, the endoscope 5001 and the CCU 5039 may be connected wirelessly, or the endoscope 5001 and the CCU 5039 may be connected via a base station in the operating room. In this case, the endoscope 5001 may simultaneously transmit not only pixel signals but also information related to the pixel signals (e.g., pixel signal processing priority, synchronization signal, etc.). The endoscope may be configured such that the scope and camera are integrated, or a light-receiving element is provided at the tip of the scope.

[0235] [CCU (Camera Control Unit)] The CCU 5039 is a control device that comprehensively controls the connected endoscope 5001 and light source device 5043. For example, as shown in FIG. 83 , the CCU 5039 is an information processing device having an FPGA 50391, a CPU 50392, a RAM 50393, a ROM 50394, a GPU 50395, and an I / F 50396. The CCU 5039 may also comprehensively control the connected display device 5041, recording device 5053, and output device 5055. For example, the CCU 5039 controls the irradiation timing, irradiation intensity, and type of irradiation light source of the light source device 5043. The CCU 5039 also performs image processing such as development processing (e.g., demosaic processing) and correction processing on pixel signals output from the endoscope 5001, and outputs the processed pixel signals (e.g., an image) to an external device such as the display device 5041. Furthermore, the CCU 5039 transmits a control signal to the endoscope 5001 to control the driving of the endoscope 5001. The control signal is, for example, information regarding imaging conditions such as the magnification and focal length of the imaging unit. The CCU 5039 may have an image down-conversion function and be configured to be able to simultaneously output a high-resolution (e.g., 4K) image to the display device 5041 and a low-resolution (e.g., HD) image to the recording device 5053.

[0236] The CCU 5039 may also be connected to external devices (e.g., recording devices, display devices, output devices, and support devices) via an IP converter that converts signals into a predetermined communication protocol (e.g., IP (Internet Protocol)). The connection between the IP converter and the external devices may be configured as a wired network, or a partial or entire network may be configured as a wireless network. For example, the IP converter on the CCU 5039 side may have a wireless communication function and transmit the received video to an IP switcher or an output-side IP converter via a wireless communication network such as a fifth-generation mobile communication system (5G) or a sixth-generation mobile communication system (6G).

[0237] [Light Source Device] The light source device 5043 is a device capable of emitting light in a predetermined wavelength band and includes, for example, multiple light sources and a light source optical system that guides the light from the multiple light sources. The light sources are, for example, a xenon lamp, an LED light source, or an LD light source. The light source device 5043 has, for example, LED light sources corresponding to the three primary colors R, G, and B, and emits white light by controlling the output intensity and output timing of each light source. Furthermore, the light source device 5043 may include a light source that can emit special light used for special light observation, in addition to a light source that emits normal light used for normal light observation. The special light is light in a predetermined wavelength band different from the normal light used for normal light observation, such as near-infrared light (light with a wavelength of 760 nm or more), infrared light, blue light, or ultraviolet light. The normal light is, for example, white light or green light. Narrowband light observation, a type of special light observation, alternately emits blue light and green light to utilize the wavelength-dependence of light absorption in body tissue, enabling high-contrast imaging of specific tissue, such as blood vessels on the surface of the mucous membrane. Furthermore, in fluorescence observation, a type of special light observation, excitation light is applied to excite a drug injected into the body tissue, and fluorescence emitted by the drug as a marker is received to obtain a fluorescence image, thereby making it easier for the surgeon to visualize body tissues that are difficult for the surgeon to see under normal light. For example, in fluorescence observation using infrared light, infrared light having an excitation wavelength band is applied to a drug such as indocyanine green (ICG) injected into the body tissue, and the fluorescence of the drug is received, making it easier to visualize the structure of the body tissue and affected areas. Furthermore, in fluorescence observation, a drug (e.g., 5-ALA) that is excited by special light in the blue wavelength band and emits fluorescence in the red wavelength band may be used. The type of light irradiated by the light source device 5043 is set under the control of the CCU 5039. The CCU 5039 may have a mode in which normal light observation and special light observation are alternately performed by controlling the light source device 5043 and the endoscope 5001. In this case, it is preferable to superimpose information based on pixel signals obtained by special light observation on pixel signals obtained by normal light observation. The special light observation may be infrared light observation, which irradiates infrared light to view areas deeper than the surface of an organ, or multispectral observation using hyperspectral spectroscopy. Furthermore, photodynamic therapy may be combined.

[0238] [Recording Device] The recording device 5053 is a device, such as a recorder, that records pixel signals (e.g., images) acquired from the CCU 5039. The recording device 5053 records images acquired from the CCU 5039 on a HDD, SSD, or optical disk. The recording device 5053 may be connected to a network within the hospital so as to be accessible from devices outside the operating room. The recording device 5053 may also have an image down-conversion or up-conversion function.

[0239] [Display Device] The display device 5041 is a device capable of displaying an image, such as a display monitor. The display device 5041 displays an image based on pixel signals acquired from the CCU 5039. The display device 5041 may also function as an input device that enables gaze recognition, voice recognition, and instruction input using gestures by including a camera and a microphone.

[0240] [Output Device] The output device 5055 is a device, such as a printer, that outputs information acquired from the CCU 5039. The output device 5055 prints, for example, a print image based on pixel signals acquired from the CCU 5039 onto paper.

[0241] [Support Device] The support device 5027 is an articulated arm including a base 5029 having an arm control device 5045, an arm 5031 extending from the base 5029, and a holder 5032 attached to the tip of the arm 5031. The arm control device 5045 is configured with a processor such as a CPU and controls the drive of the arm 5031 by operating according to a predetermined program. The support device 5027 controls the position and posture of the endoscope 5001 held by the holder 5032, for example, by controlling parameters such as the length of each link 5035 constituting the arm 5031 and the rotation angle and torque of each joint 5033 using the arm control device 5045. This allows the endoscope 5001 to be changed to a desired position or posture, allowing the scope 5003 to be inserted into the patient 5071 and the observation area within the body to be changed. The support device 5027 functions as an endoscope support arm that supports the endoscope 5001 during surgery. This allows the support device 5027 to take the place of an assistant scopist who holds the endoscope 5001. The support device 5027 may also be a device that supports a microscope device 5301 (described later) and may also be called a medical support arm. The support device 5027 may be controlled autonomously by the arm control device 5045, or may be controlled by the arm control device 5045 based on user input. For example, the control method may be a master-slave method in which the support device 5027, which serves as a slave device (replica device) serving as a patient cart, is controlled based on the movement of a master device (primary device) that serves as an operator console near the user. The support device 5027 may also be remotely controlled from outside the operating room.

[0242] The above describes an example of an endoscope system 5000 to which the technology according to the present disclosure can be applied. For example, the technology according to the present disclosure may be applied to a microscope system.

[0243] [Microscope System] Fig. 84 is a diagram showing an example of the schematic configuration of a microsurgical system to which the technology according to the present disclosure can be applied. In the following description, the same components as those in the endoscope system 5000 are denoted by the same reference numerals, and redundant description thereof will be omitted.

[0244] 84 shows a schematic diagram of an operator 5067 performing surgery on a patient 5071 on a patient bed 5069 using a microsurgical system 5300. For simplicity, the illustration of the cart 5037 of the microsurgical system 5300 is omitted, and the illustration of the microscope device 5301 that replaces the endoscope 5001 is simplified. However, the microscope device 5301 in this description may refer to the microscope unit 5303 provided at the tip of the link 5035, or may refer to the entire configuration including the microscope unit 5303 and the support device 5027.

[0245] As shown in Fig. 84, during surgery, a microsurgical system 5300 is used to display an enlarged image of the surgical site captured by a microscope device 5301 on a display device 5041 installed in an operating room. The display device 5041 is installed in a position facing the surgeon 5067, who performs various procedures on the surgical site, such as resecting the affected area, while observing the state of the surgical site using the image displayed on the display device 5041. Microsurgical systems are used, for example, in ophthalmic surgery and brain surgery.

[0246] The above describes examples of an endoscopic system 5000 and a microsurgery system 5300 to which the technology of the present disclosure can be applied. Note that the systems to which the technology of the present disclosure can be applied are not limited to these examples. For example, the support device 5027 may support another observation device or another surgical tool at its tip instead of the endoscope 5001 or the microscope unit 5303. Examples of such other observation devices include forceps, a surgeon, an insufflation tube for insufflation, or an energy treatment tool for incising tissue or sealing blood vessels by cauterization. Supporting these observation devices and surgical tools with a support device allows them to be more stably fixed in position than when medical staff support them manually, and also reduces the burden on medical staff. The technology of the present disclosure may be applied to support devices that support components other than the microscope unit.

[0247] Of the configurations described above, the technology according to the present disclosure can be suitably applied to the camera 5005. In particular, the zoom lens according to the present disclosure can be suitably applied to at least some of the optical systems of the camera 5005: the focusing optical system 50051, the zoom optical system 50052, and the focus optical system 50053.

[0248] 6. Other Embodiments The technology according to the present disclosure is not limited to the above-described embodiment and examples, and various modifications are possible.

[0249] For example, the shapes and numerical values ​​of each part shown in the above embodiment and example are merely examples of specific embodiments for implementing this technology, and the technical scope of this technology should not be interpreted in a limited manner based on these.

[0250] Furthermore, for example, the configuration may include a number of lenses different from the number of lenses shown in the above embodiment and example, or may include a lens that has substantially no refractive power.

[0251] For example, the present technology can be configured as follows. According to the present technology configured as follows, the configuration of each lens group is optimized so that it is possible to simultaneously achieve a small and lightweight zoom lens with a large aperture and high optical performance, suppress performance variation due to shooting distance, and a high maximum shooting magnification. This makes it possible to provide a small and lightweight zoom lens with a large aperture and high optical performance, suppress performance variation due to shooting distance, and a high maximum shooting magnification, as well as an imaging device equipped with such a zoom lens.

[0252] [1] A zoom lens comprising, in order from the object side to the image plane side, a first lens group having positive refractive power, a second lens group having negative refractive power, an intermediate lens group having at least one positive lens group and having positive refractive power as a whole, and a rear lens group having, at least from the object side, a negative lens group and a positive lens group, wherein, when the object distance changes from infinity to a close distance, the negative lens group and the positive lens group in the rear lens group move along the optical axis on mutually different loci, and the negative lens group in the rear lens group moves toward the image plane, thereby performing focusing, and when zooming from the wide-angle end to the telephoto end, the first lens group moves toward the object side with respect to the image plane, and the first lens group, the second lens group, the intermediate lens group, and the rear lens group each move so that a distance between adjacent lens groups changes on the optical axis, and the intermediate lens group has at least two negative lenses, and the following conditional expression is satisfied. -0.31≦(1-βrp_w ２ ) / [(1-βrn_w ２ ) *βrp_w ２]≦0 (1) where, βrn_w: lateral magnification of the negative lens group in the rear lens group at the wide-angle end and when focused on infinity, and βrp_w: lateral magnification of the positive lens group in the rear lens group at the wide-angle end and when focused on infinity. [2] A zoom lens comprising, in order from the object side to the image plane side, a first lens group having positive refractive power, a second lens group having negative refractive power, an intermediate lens group having at least one positive lens group and having positive refractive power as a whole, and a rear lens group having, at least from the object side, a negative lens group and a positive lens group, wherein, when the object distance changes from infinity to a close distance, the negative lens group and the positive lens group in the rear lens group move along the optical axis on mutually different loci, and the negative lens group in the rear lens group moves toward the image plane, thereby performing focusing, and when zooming from the wide-angle end to the telephoto end, the first lens group moves toward the object side with respect to the image plane, and the first lens group, the second lens group, the intermediate lens group, and the rear lens group each move so that a distance between adjacent lens groups changes on the optical axis, and the first lens group has three lenses, and the following conditional expression is satisfied. -0.31≦(1-βrp_w ２ ) / [(1-βrn_w ２ ) *βrp_w ２]≦0 ... (1) where, βrn_w: lateral magnification of the negative lens group in the rear lens group at the wide-angle end and when focused on infinity, βrp_w: lateral magnification of the positive lens group in the rear lens group at the wide-angle end and when focused on infinity. [3] The zoom lens according to [1] or [2] above, wherein the intermediate lens group has at least one lens group including the positive lens group, and at least one lens group in the intermediate lens group moves relative to the image plane during zooming. [4] The zoom lens according to any one of [1] to [3] above, wherein the intermediate lens group has two positive lens groups. [5] The zoom lens according to any one of [1] to [4] above, wherein the intermediate lens group satisfies the following conditional expression: 0.60<fm_w / fw<1.60 ... (2) where, fw: focal length of the entire system at the wide-angle end, fm_w: focal length of the intermediate lens group at the wide-angle end. [6] The zoom lens according to any one of [1] to [5] above, wherein the intermediate lens group satisfies the following condition: 0.25<fm_t / ft<0.70 (3) where ft: focal length of the entire system at the telephoto end, fm_t: focal length of the intermediate lens group at the telephoto end. [7] The zoom lens according to any one of [1] to [6] above, wherein the negative lens group in the rear lens group is composed of a single lens. [8] The zoom lens according to any one of [1] to [7] above, wherein the positive lens group in the rear lens group is composed of a single lens. [9] The zoom lens according to any one of [1] to [8] above, wherein the zoom lens further satisfies the following condition: 0.2<BF_w / fw≦1.2 (4) where BF_w: back focus (distance from the surface of the rear lens group closest to the image plane to the image plane) at the wide-angle end and when focusing at infinity.

[10] The zoom lens according to any one of the above [1] to [9], wherein the first lens group has a lens that satisfies the following conditional expression (5):nd_L1i / dL1i>0.50 ... (5) where, nd_L1i: refractive index at the d-line of the glass material of the lens in the first lens group that satisfies conditional formula (5), d_L1i: ratio (specific gravity) of the mass of the glass material of the lens in the first lens group that satisfies conditional formula (5) at room temperature (15 degrees Celsius to 25 degrees Celsius) to the mass of the same volume of pure water at 4 degrees Celsius under a pressure of 101.325 kPa (standard atmospheric pressure).

[11] A zoom lens according to any one of [1] to

[10] above, wherein the second lens group has a positive lens that satisfies the following conditional formula (6): 1.955<nd_L2p ... (6) where, nd_L2p: refractive index at the d-line of the positive lens in the second lens group that satisfies conditional formula (6).

[12] The zoom lens according to any one of [1] to

[11] above, wherein the intermediate lens group includes a positive lens having an aspherical surface partially formed with negative refractive action.

[13] The zoom lens according to any one of [1] to

[12] above, wherein the first lens group includes a positive lens that satisfies the following conditional expression (7): θgF_L1p-(-0.001801*νd_L1p+0.648262)>0.005 ... (7) where θgF_L1p: partial dispersion ratio between the g-line and the F-line of the positive lens in the first lens group that satisfies the conditional expression (7), and νd_L1p: Abbe number for the d-line of the positive lens in the first lens group that satisfies the conditional expression (7).

[14] The zoom lens according to any one of [1] to

[13] above, wherein the first lens group includes a negative lens that satisfies the following conditional expression (8). νd_L1n<23.0 (8) where νd_L1n: Abbe number for the d-line of the negative lens in the first lens group that satisfies the conditional expression (8).

[15] The zoom lens according to any one of the above [1] to

[14] , wherein the intermediate lens group has a positive lens that satisfies the following conditional expression (9):θgF_Lmp-(-0.001801*νd_Lmp+0.648262)>0.045 ... (9) where, θgF_Lmp: partial dispersion ratio for the g-line and the F-line of the positive lens in the intermediate lens group that satisfies the conditional expression (9), and νd_Lmp: Abbe number for the d-line of the positive lens in the intermediate lens group that satisfies the conditional expression (9).

[16] The zoom lens according to any one of the above [1] to

[15] , wherein the lens in the rear lens group that is located closest to the image plane is a negative lens that satisfies the following conditional expression (10): 0.9<(r2_rr+r1_rr) / (r2_rr-r1_rr)<6.9 ... (10) where, r1_rr: radius of curvature of the object-side surface of the lens located closest to the image plane in the rear lens group, and r2_rr: radius of curvature of the image-side surface of the lens located closest to the image plane in the rear lens group.

[17] A zoom lens includes a zoom lens and an image sensor that outputs an image signal corresponding to an optical image formed by the zoom lens, the zoom lens comprising, in order from the object side to the image plane side, a first lens group having positive refractive power, a second lens group having negative refractive power, an intermediate lens group having at least one positive lens group and having positive refractive power as a whole, and a rear lens group having at least a negative lens group and a positive lens group, in that order from the object side, when the object distance changes from infinity to a close distance, the negative lens group and the positive lens group in the rear lens group move along different loci in the optical axis direction, and the negative lens group in the rear lens group moves toward the image plane side, thereby performing focusing, and when zooming from the wide-angle end to the telephoto end, the first lens group moves toward the object side with respect to the image plane, and the first lens group, the second lens group, the intermediate lens group, and the rear lens group each move so that the intervals between adjacent lens groups change on the optical axis, An imaging device in which the intermediate lens group has at least two negative lenses, and the following conditional expression is satisfied: −0.31≦(1−βrp_w. ２ ) / [(1-βrn_w ２ ) *βrp_w ２]≦0 (1) where, βrn_w: lateral magnification of the negative lens group in the rear lens group at the wide-angle end and when focused on infinity, and βrp_w: lateral magnification of the positive lens group in the rear lens group at the wide-angle end and when focused on infinity.

[18] A zoom lens includes a zoom lens and an image sensor that outputs an image signal corresponding to an optical image formed by the zoom lens, the zoom lens comprising, in order from the object side to the image plane side, a first lens group having positive refractive power, a second lens group having negative refractive power, an intermediate lens group having at least one positive lens group and having positive refractive power as a whole, and a rear lens group having at least a negative lens group and a positive lens group, in that order from the object side, when the object distance changes from infinity to a close distance, the negative lens group and the positive lens group in the rear lens group move along different loci in the optical axis direction, and the negative lens group in the rear lens group moves toward the image plane side, thereby performing focusing, and when zooming from the wide-angle end to the telephoto end, the first lens group moves toward the object side with respect to the image plane, and the first lens group, the second lens group, the intermediate lens group, and the rear lens group each move so that the intervals between adjacent lens groups change on the optical axis, An imaging apparatus in which the first lens group has three lenses and the following condition is satisfied: -0.31≦(1−βrp_w ２ ) / [(1-βrn_w ２ ) *βrp_w ２ ]≦0 ... (1) where, βrn_w: lateral magnification of the negative lens group in the rear lens group at the wide-angle end and when focused on infinity βrp_w: lateral magnification of the positive lens group in the rear lens group at the wide-angle end and when focused on infinity

[19] The zoom lens according to any one of [1] to

[16] above, further comprising a lens having substantially no refractive power.

[20] The imaging device according to

[17] or

[18] above, further comprising a lens having substantially no refractive power.

[0253] This application claims priority based on Japanese Patent Application No. 2022-46233, filed on March 23, 2022, in the Japan Patent Office, the entire contents of which are incorporated herein by reference.

[0254] Those skilled in the art will recognize that various modifications, combinations, subcombinations, and variations may occur depending on design requirements and other factors, and are intended to be within the scope of the appended claims and their equivalents.

Claims

1. From the object side to the image plane side, a first lens group having a positive refractive power; a second lens group having negative refractive power; an intermediate lens group having at least one positive lens group and having a positive refractive power as a whole; a rear lens group having, in order from the object side, at least a negative lens group and a positive lens group, when the object distance changes from infinity to a close distance, the negative lens group and the positive lens group in the rear lens group move along different loci in the optical axis direction, and the negative lens group in the rear lens group moves toward an image plane, thereby performing focusing; during zooming from the wide-angle end to the telephoto end, the first lens group moves toward the object side with respect to an image plane, and the first lens group, the second lens group, the intermediate lens group, and the rear lens group each move such that a distance between adjacent lens groups changes on the optical axis; the intermediate lens group has at least two negative lenses; The following condition is satisfied: Zoom lens. -0.31≦(1-βrp_w 2 ) / [(1-βrn_w 2 )*βrp_w 2 ]≦0 …(1) however, βrn_w: lateral magnification of the negative lens group in the rear lens group at the wide-angle end and when focused on infinity βrp_w: lateral magnification of the positive lens group in the rear lens group at the wide-angle end and when focused on infinity Let us assume that.

2. From the object side to the image plane side, a first lens group having a positive refractive power; a second lens group having negative refractive power; an intermediate lens group having at least one positive lens group and having a positive refractive power as a whole; a rear lens group having, in order from the object side, at least a negative lens group and a positive lens group, when the object distance changes from infinity to a close distance, the negative lens group and the positive lens group in the rear lens group move along different loci in the optical axis direction, and the negative lens group in the rear lens group moves toward an image plane, thereby performing focusing; during zooming from the wide-angle end to the telephoto end, the first lens group moves toward the object side with respect to an image plane, and the first lens group, the second lens group, the intermediate lens group, and the rear lens group each move such that a distance between adjacent lens groups changes on the optical axis; the first lens group has three lenses; The following condition is satisfied: Zoom lens. -0.31≦(1-βrp_w 2 ) / [(1-βrn_w 2 )*βrp_w 2 ]≦0 …(1) however, βrn_w: lateral magnification of the negative lens group in the rear lens group at the wide-angle end and when focused on infinity βrp_w: lateral magnification of the positive lens group in the rear lens group at the wide-angle end and when focused on infinity Let us assume that.

3. The intermediate lens group has at least one lens group including the positive lens group, and at least one lens group in the intermediate lens group moves with respect to an image plane during zooming.

3. The zoom lens according to claim 2.

4. The intermediate lens group includes two positive lens groups.

3. The zoom lens according to claim 2.

5. The intermediate lens group satisfies the following condition:

3. The zoom lens according to claim 2. 0.60<fm_w / fw<1.60...(2) however, fw: focal length of the entire system at the wide-angle end fm_w: focal length of the intermediate lens group at the wide-angle end Let us assume that.

6. The intermediate lens group satisfies the following condition:

3. The zoom lens according to claim 2. 0.25<fm_t / ft<0.70...(3) however, ft: focal length of the entire system at the telephoto end fm_t: focal length of the intermediate lens group at the telephoto end Let us assume that.

7. The negative lens group in the rear lens group is composed of a single lens.

3. The zoom lens according to claim 2.

8. The positive lens group in the rear lens group is composed of a single lens.

3. The zoom lens according to claim 2.

9. Furthermore, the following condition is satisfied:

3. The zoom lens according to claim 2. 0.2<BF_w / fw≦1.2...(4) however, BF_w: Back focus at the wide-angle end and when focusing on infinity (the distance from the surface of the rear lens group closest to the image surface to the image surface) Let us assume that.

10. The first lens group has a lens that satisfies the following conditional expression (5):

3. The zoom lens according to claim 2. nd_L1i / dL1i>0.50...(5) however, nd_L1i: the refractive index at the d line of the glass material of the lens in the first lens group that satisfies the conditional expression (5), d_L1i: the ratio (specific gravity) of the mass of the glass material of the lens in the first lens group that satisfies the conditional formula (5) at room temperature (15 degrees Celsius to 25 degrees Celsius) to the mass of the same volume of pure water at 4 degrees Celsius under a pressure of 101.325 kPa (standard atmospheric pressure) Let us assume that.

11. The second lens group has a positive lens that satisfies the following condition (6):

3. The zoom lens according to claim 2. 1.955<nd_L2p...(6) however, nd_L2p: the refractive index at the d line of the positive lens in the second lens group that satisfies the conditional expression (6) Let us assume that.

12. The intermediate lens group includes a positive lens having an aspheric surface partially having a negative refractive effect.

3. The zoom lens according to claim 2.

13. The first lens group has a positive lens that satisfies the following condition (7):

3. The zoom lens according to claim 2. θgF_L1p-(-0.001801*νd_L1p+0.648262)>0.005...(7) however, θgF_L1p: partial dispersion ratio between the g line and the F line of the positive lens in the first lens group that satisfies the conditional expression (7) νd_L1p: the Abbe number for the d line of the positive lens in the first lens group that satisfies the conditional expression (7) Let us assume that.

14. The first lens group has a negative lens that satisfies the following condition (8):

3. The zoom lens according to claim 2. νd_L1n<23.0...(8) however, νd_L1n: the Abbe number for the d line of the negative lens in the first lens group that satisfies the conditional expression (8); Let us assume that.

15. The intermediate lens group has a positive lens that satisfies the following condition (9):

3. The zoom lens according to claim 2. θgF_Lmp-(-0.001801*νd_Lmp+0.648262)>0.045...(9) however, θgF_Lmp: the partial dispersion ratio of the positive lens in the intermediate lens group that satisfies the conditional expression (9) to the g-line and the F-line νd_Lmp: the Abbe number for the d-line of the positive lens in the intermediate lens group that satisfies the conditional expression (9) Let us assume that.

16. The lens in the rear lens group that is disposed closest to the image surface side is a negative lens that satisfies the following condition (10):

3. The zoom lens according to claim 2. 0.9<(r2_rr+r1_rr) / (r2_rr-r1_rr)<6.9...(10) however, r1_rr: the radius of curvature of the object-side surface of the lens arranged closest to the image surface in the rear lens group r2_rr: the radius of curvature of the image-side surface of the lens arranged closest to the image side in the rear lens group Let us assume that.

17. a zoom lens and an image sensor that outputs an image signal corresponding to an optical image formed by the zoom lens; The zoom lens comprises: From the object side to the image plane side, a first lens group having a positive refractive power; a second lens group having negative refractive power; an intermediate lens group having at least one positive lens group and having a positive refractive power as a whole; a rear lens group having, in order from the object side, at least a negative lens group and a positive lens group, when the object distance changes from infinity to a close distance, the negative lens group and the positive lens group in the rear lens group move along different loci in the optical axis direction, and the negative lens group in the rear lens group moves toward an image plane, thereby performing focusing; during zooming from the wide-angle end to the telephoto end, the first lens group moves toward the object side with respect to an image plane, and the first lens group, the second lens group, the intermediate lens group, and the rear lens group each move such that a distance between adjacent lens groups changes on the optical axis; the intermediate lens group has at least two negative lenses; The following condition is satisfied: Imaging device. -0.31≦(1-βrp_w 2 ) / [(1-βrn_w 2 )*βrp_w 2 ]≦0 …(1) however, βrn_w: lateral magnification of the negative lens group in the rear lens group at the wide-angle end and when focused on infinity βrp_w: lateral magnification of the positive lens group in the rear lens group at the wide-angle end and when focused on infinity Let us assume that.

18. a zoom lens and an image sensor that outputs an image signal corresponding to an optical image formed by the zoom lens; The zoom lens comprises: From the object side to the image plane side, a first lens group having a positive refractive power; a second lens group having negative refractive power; an intermediate lens group having at least one positive lens group and having a positive refractive power as a whole; a rear lens group having, in order from the object side, at least a negative lens group and a positive lens group, when the object distance changes from infinity to a close distance, the negative lens group and the positive lens group in the rear lens group move along different loci in the optical axis direction, and the negative lens group in the rear lens group moves toward an image plane, thereby performing focusing; during zooming from the wide-angle end to the telephoto end, the first lens group moves toward the object side with respect to an image plane, and the first lens group, the second lens group, the intermediate lens group, and the rear lens group each move such that a distance between adjacent lens groups changes on the optical axis; the first lens group has three lenses; The following condition is satisfied: Imaging device. -0.31≦(1-βrp_w 2 ) / [(1-βrn_w 2 )*βrp_w 2 ]≦0 …(1) however, βrn_w: lateral magnification of the negative lens group in the rear lens group at the wide-angle end and when focused on infinity βrp_w: lateral magnification of the positive lens group in the rear lens group at the wide-angle end and when focused on infinity Let us assume that.

19. Further comprising a lens having substantially no refractive power.

17. The zoom lens according to claim 1.

20. The zoom lens further comprising a lens having substantially no refractive power. The imaging device according to claim 17 or 18.