JP6808382B2 - Zoom lens and imaging device with it - Google Patents

Description

The present invention relates to a zoom lens and an image pickup device having the same, and is suitable for an image pickup optical system used in an image pickup device such as a digital camera, a video camera, a TV camera, a surveillance camera, and a silver salt film camera.

It is required that the imaging optical system used in the imaging device (camera) includes a wide imaging angle of view, has high resolution, and is a compact zoom lens in the whole system. Further, it is required to have high optical performance on the entire screen corresponding to a large-sized (for example, full size or ASP size) image sensor, and to be a zoom lens that can easily image a close object point.

Conventionally, as a zoom lens having a wide angle of view and a small size in the whole system, a negative lead type zoom lens in which a lens group having a negative refractive power is arranged on the object side is known. Among negative lead type zoom lenses, there is known a zoom lens in which focusing is performed using a compact and lightweight lens group (Patent Document 1).

In Patent Document 1, the lens group is composed of the first lens group to the fifth lens group having negative, positive, positive, negative, and positive refractive powers in order from the object side to the image side, and zooming is performed by changing the distance between adjacent lens groups. A five-group zoom lens that focuses on a fourth lens group is disclosed. Further, in order to reduce aberration fluctuation during focusing, a negative lead type zoom lens using a floating method in which a plurality of lens groups (subgroups) are moved during focusing is known (Patent Documents 2 and 3).

Patent Document 2 is composed of a first lens group to a fourth lens group having negative, positive, negative, and positive refractive powers in this order from the object side to the image side. Then, in a zoom lens in which the distance between adjacent lens groups changes during zooming, a zoom lens using floating that moves the second lens group and the third lens group during focusing is disclosed.

Patent Document 3 is composed of a first lens group to a third lens group having negative, positive, and positive refractive powers in this order from the object side to the image side. Then, in a zoom lens in which the distance between adjacent lens groups changes during zooming, a zoom lens using a floating that moves a part of a part group of the second lens group and the third lens group during focusing is disclosed.

Japanese Unexamined Patent Publication No. 2012-47813 JP 2015-197593 Japanese Unexamined Patent Publication No. 2012-212123

The zoom lens used in the image pickup device has a wide angle of view and the entire lens system is small, the focus lens group is small and lightweight, and it is easy to take close-range images, and there is little aberration fluctuation during focusing. It is requested. In a negative lead type zoom lens, it is important to appropriately set the refractive power and lens configuration of each lens group in order to obtain high optical performance over the entire zoom range and object distance while the entire system is small. ..

For example, it is important to appropriately set the refractive power and moving conditions of the first lens group and the second lens group during zooming, the selection of the lens group to be moved when floating is used, and the refractive power and moving conditions. Come on. In addition, if the angle of incidence of the light flux on the image sensor arranged on the image plane becomes large, the optical performance around the screen deteriorates when a large image sensor is used. For this reason, it is important to appropriately set the refractive power arrangement, the refractive power, and the like of each lens group. If these settings are not appropriate, it will be difficult to obtain a zoom lens with a small size, a wide angle of view, and high optical performance over the entire object distance.

An object of the present invention is to provide a zoom lens that can easily obtain high optical performance over an entire object distance while being compact and having a wide angle of view as a whole.

The zoom lens as one aspect of the present invention is a first lens group having a negative refractive power, a second lens group having a positive refractive power, and a first portion having a positive refractive power arranged in order from the object side to the image side. It has a group, a second subgroup of negative power, and a third subgroup of positive power, and the distance between the first lens group and the second lens group is shorter at the telephoto end than at the wide-angle end. In a zoom lens where the distance between adjacent lens groups changes during zooming,
When focusing from infinity to the closest distance, the first lens group moves to the object side, the second lens group moves to the image side, and the first lens group moves in zooming from the wide-angle end to the telephoto end. When the amount is M1, the amount of movement of the second lens group in zooming from the wide-angle end to the telephoto end is M2 , the focal length of the first lens group is f1, and the focal length of the second lens group is f2 .
0.00 <M1 / M2 <1.00
-1.50 <f1 / f2 <-0.60
It is characterized by satisfying the conditional expression.

According to the present invention, it is possible to obtain a zoom lens that can easily obtain high optical performance over an entire object distance while being compact and having a wide angle of view as a whole.

Cross-sectional view of the lens of Example 1 (A), (B), (C), (D) Aberration diagram at the wide-angle end, the zoom position of the middle 1, the zoom position of the middle 2, and the telephoto end when focusing on the infinity of Example 1. (A), (B), (C), (D) Aberration diagram at the wide-angle end, the zoom position of the middle 1, the zoom position of the middle 2, and the telephoto end when focusing on the closest distance of the first embodiment. Cross-sectional view of the lens of Example 2 (A), (B), (C), (D) Aberration diagram at the wide-angle end, the zoom position of the middle 1, the zoom position of the middle 2, and the telephoto end when focusing at infinity in Example 2. (A), (B), (C), (D) Aberration diagram at the wide-angle end, the zoom position of the middle 1, the zoom position of the middle 2, and the telephoto end when focusing on the closest distance of the second embodiment. Cross-sectional view of the lens of Example 3 (A), (B), (C), (D) Aberration diagram at the wide-angle end, the zoom position of the middle 1, the zoom position of the middle 2, and the telephoto end when focusing at infinity in Example 3. (A), (B), (C), (D) Aberration diagram at the wide-angle end, the zoom position of the middle 1, the zoom position of the middle 2, and the telephoto end when focusing on the closest distance of Example 3. Cross-sectional view of the lens of Example 4 (A), (B), (C), (D) Aberration diagram at the wide-angle end, the zoom position of the middle 1, the zoom position of the middle 2, and the telephoto end when focusing at infinity in Example 4. (A), (B), (C), (D) Aberration diagram at the wide-angle end, the zoom position of the middle 1, the zoom position of the middle 2, and the telephoto end when focusing on the closest distance of Example 4. Cross-sectional view of the lens of Example 5 (A), (B), (C), (D) Aberration diagram at the wide-angle end, the zoom position of the middle 1, the zoom position of the middle 2, and the telephoto end when focusing at infinity in Example 5. (A), (B), (C), (D) Aberration diagram at the wide-angle end, the zoom position of the middle 1, the zoom position of the middle 2, and the telephoto end when focusing on the closest distance of Example 5. Cross-sectional view of the lens of Example 6 (A), (B), (C), (D) Aberration diagram at the wide-angle end, the zoom position of the middle 1, the zoom position of the middle 2, and the telephoto end when focusing at infinity in Example 6. (A), (B), (C), (D) Aberration diagram at the wide-angle end, the zoom position of the middle 1, the zoom position of the middle 2, and the telephoto end when focusing on the closest distance of Example 6. Schematic diagram of the main part of the image pickup apparatus of the present invention

Hereinafter, preferred embodiments of the present invention will be described with reference to the accompanying drawings. The zoom lens of the present invention has a first lens group having a negative refractive power, a second lens group having a positive refractive power, and a first subset group (FP1) having a positive refractive power arranged in order from the object side to the image side. It is composed of a second subgroup of negative power (FN) and a third subgroup of positive power (FP2). At the telephoto end, the distance between the first lens group and the second lens group is narrower than at the wide-angle end, and the distance between adjacent lens groups changes during zooming.

When focusing from infinity to the closest distance, the first subgroup moves to the object side and the second subgroup moves to the image side. Here, the lens group refers to a lens system composed of one or a plurality of lenses divided by a change in the lens spacing in the optical axis direction due to zooming.

FIG. 1 is a cross-sectional view of the lens of the first embodiment. 2 (A) to 2 (D) focus on the wide-angle end (short focal length end), the zoom position of the middle 1, the zoom position of the middle 2, and the telephoto end (long focal length end) of the first embodiment. It is an aberration diagram at the time of. 3 (A) to 3 (D) are aberration diagrams when focusing on the wide-angle end of Example 1, the zoom position of the middle 1, the zoom position of the middle 2, and the closest distance at the telephoto end.

Here, the closest distance represents from the surface number 1 to the object point, and is 50 mm at the wide-angle end, 80 mm at the zoom position of the middle 1, 80 mm at the zoom position of the middle 2, and 200 mm at the telephoto end. The first embodiment is a zoom lens having a zoom ratio of 2.83 times and an aperture ratio of about 2.89 to 5.77.

FIG. 4 is a cross-sectional view of the lens of the second embodiment. 5 (A) to 5 (D) are aberration diagrams when focusing on the wide-angle end, the zoom position of the middle 1, the zoom position of the middle 2, and the telephoto end of the second embodiment. 6 (A) to 6 (D) are aberration diagrams when focusing on the wide-angle end of Example 2, the zoom position of the middle 1, the zoom position of the middle 2, and the closest distance at the telephoto end.

The closest distance represents the surface number 1 to the object point, which is 50 mm at the wide-angle end, 80 mm at the zoom position of the middle 1, 80 mm at the zoom position of the middle 2, and 200 mm at the telephoto end. The second embodiment is a zoom lens having a zoom ratio of 2.83 times and an aperture ratio of about 2.88 to 5.77.

FIG. 7 is a cross-sectional view of the lens of the third embodiment. 8 (A) to 8 (D) are aberration diagrams when the wide-angle end of Example 3, the zoom position of the middle 1, the zoom position of the middle 2, and the telephoto end are focused to infinity. 9 (A) to 9 (D) are aberration diagrams when focusing on the wide-angle end of Example 3, the zoom position of the middle 1, the zoom position of the middle 2, and the closest distance at the telephoto end.

The closest distance represents the surface number 1 to the object point, which is 50 mm at the wide-angle end, 80 mm at the zoom position of the middle 1, 80 mm at the zoom position of the middle 2, and 200 mm at the telephoto end. Example 3 is a zoom lens having a zoom ratio of 2.85 times and an aperture ratio of about 2.06 to 5.78.

FIG. 10 is a cross-sectional view of the lens of the fourth embodiment. 11 (A) to 11 (D) are aberration diagrams when the wide-angle end of Example 4, the zoom position of the middle 1, the zoom position of the middle 2, and the telephoto end are focused to infinity. 12 (A) to 12 (D) are aberration diagrams when focusing on the wide-angle end of Example 4, the zoom position of the middle 1, the zoom position of the middle 2, and the closest distance at the telephoto end.

The closest distance represents the surface number 1 to the object point, which is 50 mm at the wide-angle end, 80 mm at the zoom position of the middle 1, 80 mm at the zoom position of the middle 2, and 200 mm at the telephoto end. Example 4 is a zoom lens having a zoom ratio of 2.83 times and an aperture ratio of about 2.06 to 5.05.

FIG. 13 is a cross-sectional view of the lens of the fifth embodiment. 14 (A) to 14 (D) are aberration diagrams when focusing on the wide-angle end, the zoom position of the middle 1, the zoom position of the middle 2, and the telephoto end of the fifth embodiment. 15 (A) to 15 (D) are aberration diagrams when focusing on the wide-angle end of Example 5, the zoom position of the middle 1, the zoom position of the middle 2, and the closest distance at the telephoto end.

The closest distance represents the surface number 1 to the object point, which is 50 mm at the wide-angle end, 80 mm at the zoom position of the middle 1, 80 mm at the zoom position of the middle 2, and 200 mm at the telephoto end. Example 5 is a zoom lens having a zoom ratio of 2.83 times and an aperture ratio of about 2.88 to 5.77.

FIG. 16 is a cross-sectional view of the lens of the sixth embodiment. 17 (A) to 17 (D) are aberration diagrams when focusing on the wide-angle end, the zoom position of the middle 1, the zoom position of the middle 2, and the telephoto end of the sixth embodiment. 18 (A) to 18 (D) are aberration diagrams when focusing on the wide-angle end of Example 6, the zoom position of the middle 1, the zoom position of the middle 2, and the closest distance at the telephoto end.

The closest distance represents the surface number 1 to the object point, which is 50 mm at the wide-angle end, 80 mm at the zoom position of the middle 1, 80 mm at the zoom position of the middle 2, and 200 mm at the telephoto end. Example 6 is a zoom lens having a zoom ratio of 2.83 times and an aperture ratio of about 2.88 to 5.77. FIG. 19 is a schematic view of a main part of the image pickup apparatus of the present invention.

The zoom lens of each embodiment is an imaging optical system used in an imaging device such as a video camera, a digital camera, and a silver halide film camera. In the cross-sectional view of the lens, the left side is the object side (front) and the right side is the image side (rear). The zoom lens of each embodiment may be used for the projector. In this case, the left side is the screen side and the right side is the projected image side.

In the lens cross-sectional view, OL is a zoom lens. i indicates the order of the lens groups from the object side, and Li is the i-th lens group. FP1 represents the first subgroup of positive power, FN represents the second subgroup of negative power, and FP2 represents the third subgroup of positive power. SP1 is an aperture stop. SP2 is a flare cut aperture. G is an optical block corresponding to an optical filter, a face plate, an infrared cut filter, or the like.

IP is an image plane, and when used as an image pickup optical system for video cameras and digital still cameras, it is used on the image pickup surface of solid-state image sensors (photoelectric conversion elements) such as CCD sensors and CMOS sensors, and when used as a silver halide film camera. Corresponds to the film surface.

In the cross-sectional view of the lens, the solid arrow indicates the movement locus of each lens group in zooming from the wide-angle end to the telephoto end when the lens is in focus at infinity. The dotted arrow indicates the movement locus of each lens group during zooming from the wide-angle end to the telephoto end when the lens is in focus at the closest distance. The arrow relating to the focus indicates the moving direction of the first subgroup FP1 and the second subgroup FN when focusing from infinity to the closest distance.

In the longitudinal aberration diagram, d is the d line (wavelength 587.6 nm) and g is the g line (wavelength 435.8 nm). M is the meridional image plane of the d line, and S is the sagittal image plane of the d line. Chromatic aberration of magnification is represented by the g-line. ω is a half angle of view (degrees), and Fno is an F number. In each of the following embodiments, the wide-angle end and the telephoto end refer to the zoom positions when the variable magnification lens group is located at both ends of the movable range on the optical axis on the mechanism. The zoom position of the middle 1 is the zoom position where the first lens group L1 is located closest to the image side in zooming.

The lens configurations of the zoom lenses of Examples 1, 2 and 6 are as follows in order from the object side to the image side. Negative refractive power first lens group L1, aperture aperture SP1, positive refractive power second lens group L2, positive refractive power first subset FP1, negative refractive power second subset FN, positive It is composed of a third subset FP2 of refractive power. The first subgroup FP1 with a positive refractive power and the second subgroup FN with a negative refractive power constitute the third lens group L3. The third subgroup FP2 of positive refractive power constitutes the fourth lens group L4.

The distance between adjacent lens groups changes during zooming. In order to reduce the size of the entire system with a zoom ratio of about 3 times, the zoom configuration has a first lens group L1 with a negative refractive power and a second lens group L2 with a positive refractive power in order from the object side to the image side. It has a negative lead lens configuration.

A positive reed zoom configuration in which the first lens group has a positive refractive power is advantageous for increasing the zoom ratio, but the effective diameter of the front lens becomes large when aiming for a wide angle of view at the wide-angle end. Therefore, at a zoom magnification of about 3 times, a negative lead zoom configuration in which the first lens group has a negative refractive power is more advantageous for miniaturization of the entire system.

When zooming from the wide-angle end to the telephoto end, the first lens group L1 moves toward the object side with a trajectory convex toward the image side, and the aperture diaphragm SP1 moves toward the object side. Further, the second lens group L2 moves to the object, the first subgroup FP1 and the second subgroup FN move integrally to the object side, and the third subgroup FP2 moves to the image side.

When zooming from the wide-angle end to the telephoto end, by moving the first lens group L1 so that it is located on the object side, the total length of the lens at the wide-angle end is shortened, and the aperture aperture SP1 and the first lens group L1 are brought closer to each other. , We are trying to reduce the effective diameter of the front lens. Further, by moving the movement locus of the first lens group L1 toward the image side in a convex locus during zooming, the image plane characteristics in zooming are satisfactorily corrected.

Further, during zooming, the aperture diaphragm SP1 is moved independently of each lens group L1 (with a different trajectory). Specifically, at the zoom position of the intermediate focal length, the lens moves away from the second lens group L2 toward the object side and moves in a trajectory that is convex toward the object side with respect to the second lens group L2. Alternatively, the locus is such that the distance between the aperture diaphragm SP1 and the second lens group L2 narrows from the wide-angle end to the telephoto end. As a result, the underline flare of off-axis rays at the zoom position from the wide-angle end to the intermediate focal length is cut, and the optical performance at the zoom position from the wide-angle end to the intermediate focal length is improved.

Further, by setting the first subgroup FP1 and the second subgroup FN as different movement loci with respect to the second lens group L2 having a positive refractive power in zooming, the image plane at the zoom position of the intermediate focal length in zooming. The characteristics are corrected well. Further, in zooming, the third subgroup FP2 having a positive refractive power is moved to the image side to have a scaling effect. As a result, the amount of movement of the second lens group L2, the first subgroup FP1 and the second subgroup FN is reduced, and the total length of the lens at the telephoto end is shortened. Further, the final third subgroup FP2 is composed of one positive lens.

By making the third subgroup FP2 have a positive refractive power, the exit pupil at the wide-angle end is moved away to the object side, and the telecentricity is improved. That is, the incident height of the luminous flux on the image plane is reduced.

Since the third subgroup FP2 is arranged at a position close to the imaging point (image plane) and the effective diameter of the lens becomes large, if the third subgroup FP2 is composed of a plurality of lenses, the thickness of the lens increases and the entire lens becomes thicker. The system becomes large. Therefore, it is composed of one lens. Further, a second subgroup FN having a negative refractive power is arranged on the object side of the third subgroup FP2 having a positive refractive power. By making the third subgroup FP2 a positive refractive power, the effective diameter of the second subgroup FN on the object side of the third subgroup FP2 is reduced, and the total length of the lens is shortened by making it a negative refractive power. doing.

Further, the first subgroup FP1 having a positive refractive power is arranged on the object side of the second subgroup FN having a negative refractive power. The first subgroup FP1 having a positive refractive power is arranged on the object side of the second subgroup FN. As a result, of the first subgroup FP1, the second subgroup FN, and the third subgroup FP2 (fourth lens group L4), the first subgroup FP1 and the third subgroup FP2 of positive refractive power are positively refracted. The power is dispersed.

Since the third subgroup FP2 arranged in front of the image plane has a large effective diameter, if the refractive power is strong, the lens wall thickness becomes thick, which affects the camera thickness at the time of retracting. Therefore, by giving the first subgroup FP1 having a small effective diameter a positive refractive power, the positive refractive power of the third subgroup FP2 is weakened and the lens wall thickness is reduced.

Further, the first subgroup FP1 having a positive refractive power different from the second subgroup FN having a negative refractive power is arranged on the object side. As a result, the positional sensitivity of the first subgroup FP1 and the second subgroup FN is increased. Further, the first subgroup FP1 is arranged on the object side of the second subgroup FN at a position closer to the image side than the aperture stop SP1, so that the effective diameter is smaller than that of the second subgroup FN. Therefore, the first subgroup FP1 and the second subgroup FN are used as a focusing lens group to reduce the amount of movement during focusing from infinity to the nearest distance, and facilitate rapid focusing.

The first subgroup FP1 of positive refractive power is configured to move to the object side when focusing from infinity to the closest distance. The second subgroup FN of negative refractive power is configured to move to the image side when focusing from infinity to the closest distance. By adopting a structure in which the first subgroup FP1 and the second subgroup FN move at the same time when focusing from infinity to the closest distance, for example, the second subgroup FN can be moved to the closest distance as compared with focusing alone. Makes it easier to focus.

In the lens cross-sectional view, the solid line curve FP1a and the dotted line curve FP1b with respect to the first subgroup FP1 are movement loci for correcting image plane fluctuations due to scaling when focusing at infinity and the closest distance, respectively. Is. Further, when focusing from infinity to a short-distance object point, the first subgroup FP1 is extended to the object side as shown by the arrow FP1c.

The solid curve FNa and the dotted curve FNb with respect to the second subgroup FN are movement loci for correcting image plane fluctuations due to scaling when focusing at infinity and the closest distance, respectively. Further, when focusing from infinity to the nearest distance at the telephoto end, the second subgroup FN is moved toward the image side as shown by the arrow FNc.

The lens configurations of the zoom lenses of Examples 3 and 4 are as follows in order from the object side to the image side. Negative refractive power first lens group L1, flare cut aperture SP2, positive refractive power second lens group L2, aperture aperture SP1, positive refractive power first segment group FP1, negative refractive power second portion It is composed of the group FN and the third subgroup FP2 of positive refractive power.

The lens configuration of the zoom lens of the fifth embodiment is as follows in order from the object side to the image side. Negative refractive power first lens group L1, aperture aperture SP1, positive refractive power second lens group L2, flare cut aperture SP2, positive refractive power first subset FP1, negative refractive power second portion It is composed of the group FN and the third subgroup FP2 of positive refractive power.

In Examples 3, 4 and 5, the first subgroup FP1 of positive power constitutes the third lens group L3, and the second subgroup FN of negative power constitutes the fourth lens group L4. The third subgroup FP2 of the refractive power of the above constitutes the fifth lens group L5. The distance between adjacent lens groups changes during zooming. The flare cut diaphragm SP2 has a constant opening diameter.

In order to reduce the size of the entire system by setting the zoom ratio to about 3 times, the zoom configuration consists of the first lens group L1 with negative refractive power and the second lens group L2 with positive refractive power in order from the object side to the image side. It has a negative lead lens configuration. A positive reed zoom configuration in which the first lens group has a positive refractive power is advantageous for high zoom, but the front lens diameter becomes large. Therefore, at a zoom magnification of about 3 times, a negative lead zoom configuration in which the first lens group L1 has a negative refractive power is more advantageous for miniaturization of the entire system.

When zooming from the wide-angle end to the telephoto end, the first lens group L1 moves toward the object side with a trajectory convex toward the image side, and the flare cut aperture SP2 moves toward the object side. Further, the second lens group L2 moves to the object, the first subgroup FP1 moves to the object side, the second subgroup FN moves to the object side, and the third subgroup FP2 moves to the image side. The aperture stop SP moves on the same trajectory as the second lens group L2.

When zooming from the wide-angle end to the telephoto end, by moving the first lens group L1 so that it is located on the object side, the total length of the lens at the wide-angle end is shortened, and the aperture aperture SP1 and the first lens group L1 are brought closer to each other. , We are trying to reduce the effective diameter of the front lens. Further, during zooming, in Examples 3 and 4, the flare cut aperture SP2 is set to a different trajectory from each lens group, and at the zoom position of the intermediate focal length, the object is separated from the second lens group L2 to the object side with respect to the second lens group L2. It moves in a trajectory that becomes convex to the side.

Alternatively, the locus is such that the distance between the aperture diaphragm SP1 and the second lens group L2 narrows from the wide-angle end to the telephoto end. As a result, the underline flare of off-axis rays at the zoom position from the wide-angle end to the intermediate focal length is cut, and the optical performance at the zoom position from the wide-angle end to the intermediate focal length is improved. Further, by setting the first subgroup FP1 and the second subgroup FN of the positive refractive power as different movement loci with respect to the second lens group L2 of the positive refractive power in zooming, the intermediate focal length in zooming can be determined. The image plane characteristics are satisfactorily corrected at the zoom position.

Further, in zooming, the third subgroup FP2 having a positive refractive power is moved to the image side to have a scaling effect. As a result, the amount of movement of the second lens group L2, the first subgroup FP1 and the second subgroup FN is reduced, and the total length of the lens at the telephoto end is shortened. Further, the final third subgroup FP2 is composed of one positive lens. By making the third subgroup FP2 have a positive refractive power, the exit pupil at the wide-angle end is moved away to the object side, and the telecentricity is improved.

Since the third subgroup FP2 is arranged at a position close to the imaging point (image plane) and the effective diameter of the lens becomes large, if the third subgroup FP2 is composed of a plurality of lenses, the thickness of the lens increases and the entire lens becomes thicker. The system becomes large. Therefore, it is composed of one lens. Further, a second subgroup FN having a negative refractive power is arranged on the object side of the third subgroup FP2 having a positive refractive power. By making the third subgroup FP2 a positive refractive power, the effective diameter of the second subgroup FN on the object side of the third subgroup FP2 is reduced, and by making it a negative refractive power, the total length of the lens is shortened. ing. Further, the first subgroup FP1 having a positive refractive power is arranged on the object side of the second subgroup FN having a negative refractive power.

The first subgroup FP1 having a positive refractive power is arranged on the object side of the second subgroup FN. As a result, the positive refractive powers of the first subgroup FP1 and the third subgroup FP2 among the first subgroup FP1, the second subgroup FN, and the third subgroup FP2 arranged on the image side are dispersed. doing.

Since the third subgroup FP2 arranged in front of the image plane has a large effective diameter, if the refractive power is strong, the lens wall thickness becomes thick, which affects the camera thickness at the time of retracting. Therefore, by giving the first subgroup FP1 having a small effective diameter a positive refractive power, the positive refractive power of the third subgroup FP2 is weakened and the lens wall thickness is reduced. Further, by arranging the first subgroup FP1 having a positive refractive power different from the second subgroup FN having a negative power on the object side, the position sensitivity of the first subgroup FP1 and the second subgroup FN The degree is high.

Further, the first subgroup FP1 is arranged on the object side of the second subgroup FN at a position closer to the image side than the aperture stop SP1, so that the effective diameter is smaller than that of the second subgroup FN. Therefore, the first subgroup FP1 and the second subgroup FN are used as a focusing lens group to reduce the amount of movement during focusing from infinity to the nearest distance, and facilitate rapid focusing.

The first subgroup FP1 of positive refractive power is configured to move to the object side when focusing from infinity to the closest distance. The second subgroup FN of negative refractive power is configured to move to the image side when focusing from infinity to the closest distance. By adopting a structure in which the first subgroup FP1 and the second subgroup FN move at the same time when focusing from infinity to the closest distance, for example, the second subgroup FN can be moved to the closest distance as compared with focusing alone. Makes it easier to focus.

In the lens cross-sectional view, the solid line curve FP1a and the dotted line curve FP1b with respect to the first subgroup FP1 are movement loci for correcting image plane fluctuations due to scaling when focusing at infinity and the closest distance, respectively. Is.

Further, when focusing from infinity to a short-distance object point, the first subgroup FP1 is extended to the object side as shown by the arrow FP1c. The solid curve FNa and the dotted curve FNb with respect to the second subgroup FN are movement loci for correcting image plane fluctuations due to scaling when focusing at infinity and the closest distance, respectively. Further, when focusing from infinity to the nearest distance at the telephoto end, the second subgroup FN is moved toward the image side as shown by the arrow FNc.

In each embodiment, the amount of movement of the first lens group L1 in zooming from the wide-angle end to the telephoto end is M1, and the amount of movement of the second lens group L2 is M2. At this time,
0.00 <M1 / M2 <1.00 ... (1)
Satisfies the conditional expression.

Here, the sign of the amount of movement is negative when the lens group is located on the object side and positive when it is located on the image side at the telephoto end as compared with the wide-angle end.

Conditional expression (1) defines the ratio of the amount of movement of the first lens group L1 and the amount of movement of the second lens group L2 in zooming from the wide-angle end to the telephoto end. When the amount of movement of the first lens group L1 exceeds the upper limit of the conditional expression (1), the total length of the lens at the wide-angle end becomes short. By shortening the total lens length at the wide-angle end, the distance between the first lens group L1 and the aperture diaphragm SP1 becomes narrower, and the effective diameter of the first lens group L1 becomes smaller.

Therefore, although it is advantageous for miniaturization of the first lens group L1, the amount of movement in zooming of the first lens group L1 and the second lens group L2 becomes large. As a result, the total length of the lens at the telephoto end is increased, the number of lens barrel members for performing the retracted state is increased, and the radial direction is increased, which is not preferable.

When the first lens group L1 moves so as to exceed the lower limit value of the conditional expression (1), the first lens group L1 becomes a movement locus located from the object side to the image side during zooming, so that it becomes a wider angle end than the telephoto end. The total length of the lens becomes longer. Then, at the wide-angle end, the aperture diaphragm SP1 and the first lens group L1 are in the direction of spreading, so that the effective diameter of the first lens group L1 becomes large, the optical axis direction of the first lens group L1 becomes long, and the radial direction becomes long. It's getting bigger. It is preferable that the numerical range of the conditional expression (1) is as follows.
0.10 <M1 / M2 <0.80 ... (1a)

Further, more preferably, when the numerical range of the conditional expression (1a) is set as follows, the effect meant by the conditional expression described above can be obtained to the maximum.
0.20 <M1 / M2 <0.60 ... (1b)

In each embodiment, by configuring as described above, it is possible to obtain a zoom lens in which the entire system is compact, has high performance, and is easy to focus on the closest distance.

It is more preferable that one or more of the following conditional expressions are satisfied in each embodiment. Let MfFN be the amount of movement of the second subgroup FN in focusing from infinity to the nearest distance, and MfFP1 be the amount of movement of the first subgroup FP1. Let the focal length of the first subgroup FP1 be fP1 and the focal length of the second subgroup FN be fN. Let the focal length of the third subgroup FP2 be fP2.

When focusing at infinity, the distance between the second subgroup FN and the third subgroup FP2 at the wide-angle end is DW4, and the focal length of the entire system at the wide-angle end is fW. Let DW2 be the distance between the second lens group L2 and the first subgroup FP1 at the wide-angle end when focusing at infinity. Let the focal length of the first lens group L1 be f1 and the focal length of the second lens group L2 be f2. Let the movement amount of the first subgroup FP1 in zooming from the wide-angle end to the telephoto end be MFP1. Let the amount of movement of the second subgroup FN in zooming from the wide-angle end to the telephoto end be MFN, and the amount of movement of the third subgroup FP2 in zooming from the wide-angle end to the telephoto end be MFP2.

The radius of curvature of the lens surface on the most object side of the second subgroup FN is FNR1, and the radius of curvature of the lens surface on the most image side of the second subgroup FN is FNR2. The radius of curvature of the lens surface on the most object side of the first subgroup FP1 is FP1R1, and the radius of curvature of the lens surface on the most image side of the first subgroup FP1 is FP1R2. The radius of curvature of the lens surface on the most object side of the third subgroup FP2 is FP2R1, and the radius of curvature of the lens surface on the most image side of the third subgroup FP2 is FP2R2.

The zoom lens has an aperture diaphragm SP1, the length from the aperture diaphragm SP1 at the wide-angle end to the image plane is DSPI, and the length from the aperture diaphragm SP1 at the wide-angle end to the lens surface on the object side of the first subgroup FP1 is on the optical axis. Let the length be DSP1. The length on the optical axis from the aperture diaphragm SP1 at the wide-angle end to the lens surface on the object side of the second subgroup FN is defined as the DSN.

When zooming from the wide-angle end to the telephoto end, the first lens group L1 moves in a convex locus toward the image side, and during zooming, the zoom position where the first lens group L1 is located closest to the image side is defined as the zoom position of the middle 1. To do. At this time, the amount of movement of the first lens group L1 from the wide-angle end to the intermediate 1 zoom position is M1a, and the amount of movement of the first lens group L1 from the intermediate 1 zoom position to the telephoto end is M1b.

Let G1Nd be the refractive index of the material of the lens on the most object side of the first lens group L1. Here, the sign of the amount of movement in focusing from infinity to the nearest distance is negative when moving to the object side and positive when moving to the image side. At this time, it is preferable to satisfy one or more of the following conditional expressions.

-1.00 <MfFP1 / MfFN <0.00 ... (2)
-1.80 <fP1 / fN <-0.30 ... (3)
-2.00 <fP2 / fN <-0.50 ... (4)
0.40 <fP2 / fP1 <1.20 ... (5)
0.10 <DW4 / fW <1.00 ... (6)
0.10 <DW2 / fW <1.00 ... (7)
-1.50 <f1 / f2 <-0.60 ... (8)
-1.50 <M1 / fW <-0.20 ... (9)
1.00 <M2 / MFP1 <1.50 ... (10)
-12.00 <MFN / MFP2 <-2.00 ... (11)
1.00 <(FNR2 + FNR1) / (FNR2-FNR1) <15.00
... (12)
0.20 <(FP1R2 + FP1R1) / (FP1R2-FP1R1) <5.00
... (13)
0.20 <(FP2R2 + FP2R1) / (FP2R2-FP2R1) <3.00
... (14)
0.05 <DSP1 / DSIP <0.60 ... (15)
0.20 <DSN / DSNP <0.70 ... (16)
-0.50 <M1a / M1b <0.00 ... (17)
1.920 <G1Nd <2.060 ... (18)

Next, the technical meaning of each of the above conditional expressions will be described. Conditional expression (2) limits the ratio of the amount of movement of the first subgroup FP1 and the second subgroup FN in focusing from infinity to the closest distance. When the amount of movement of the first subgroup FP1 with respect to the second subgroup FN exceeds the upper limit of the conditional expression (2), the position sensitivity of the first subgroup FP1 is higher than that of the second subgroup FN. Therefore, the amount of movement during focusing can be reduced. However, in addition to the fluctuation of spherical aberration, the fluctuation of coma becomes large, which is not preferable.

When the amount of movement of the second subgroup FN with respect to the first subgroup FP1 exceeds the lower limit of the conditional expression (2), the second subgroup FN and the third subgroup FP2 are likely to physically interfere with each other. This is not preferable because it makes focusing to a desired macro region difficult.

The conditional expression (3) defines the ratio of the refractive power of the first subgroup FP1 to the refractive power of the second subgroup FN. When the negative refractive power of the second subgroup FN becomes weaker (when the absolute value of the negative refractive power becomes smaller) beyond the upper limit of the conditional expression (3), focusing to the closest vicinity of the second subgroup FN at the wide-angle end. The amount of movement at that time becomes large. Then, the second subgroup FN and the third subgroup FP2 are likely to interfere with each other, and focusing to a desired macro region becomes difficult, which is not preferable.

When the negative refractive power of the second subgroup FN becomes stronger than the lower limit of the conditional expression (3) (when the absolute value of the negative refractive power becomes larger), the amount of movement in Focusing can be shortened, so that the entire system is compact. It is advantageous for conversion. However, it is not preferable because the eccentric sensitivity becomes high and the assembly manufacturing becomes difficult.

The conditional expression (4) defines the ratio of the refractive power of the third subgroup FP2 to the refractive power of the second subgroup FN. When the positive refractive power of the third subgroup FP2 with respect to the second subgroup FN becomes stronger beyond the upper limit of the conditional expression (4), the incident angle at the wide-angle end improves, but the positive refraction of the third subgroup FP2. The power becomes stronger. Therefore, the thickness of the third subgroup FP2 in the optical axis direction increases, and the entire system becomes large, which is not preferable. The third subgroup FP2 is a lens having a large effective diameter because it is arranged near the image plane, but it is not good because the central wall thickness increases as the refractive power becomes stronger due to the larger effective diameter.

If the refractive power of the third subgroup FP2 with respect to the second subgroup FN becomes weaker than the lower limit of the conditional expression (4), the incident angle of the light flux at the wide-angle end becomes tight, which is not preferable.

The conditional expression (5) defines the ratio of the refractive powers of the first subgroup FP1 and the third subgroup FP2. If the positive refractive power of the third subgroup FP2 with respect to the first subgroup FP1 becomes weaker than the upper limit of the conditional expression (5), the incident angle of the light flux at the wide-angle end becomes tight, which is not preferable. Further, since the refractive power of the first subgroup FP1 becomes stronger, the eccentric sensitivity of the first subgroup FP1 becomes higher, which makes assembly and manufacturing difficult, which is not preferable.

When the positive refractive power of the third subgroup FP2 with respect to the first subgroup FP1 becomes stronger beyond the lower limit of the conditional expression (5), the incident angle of the light beam at the wide-angle end becomes better (smaller), but the third part As the refractive power of the group FP2 becomes stronger, the thickness of the third subgroup FP2 in the optical axis direction increases. And it is not preferable because the whole system becomes large.

Conditional expression (6) defines the distance DW4 between the second subgroup FN and the third subgroup FP2 at the wide-angle end when focusing at infinity. When the DW4 becomes larger than the upper limit of the conditional expression (6), the amount of movement of the second subgroup FN in focusing from infinity to the nearest distance is sufficiently secured, but the third subgroup FP2 is arranged on the image side. It will be in the direction of being done. Therefore, the amount of movement of the third subgroup FP2 in zooming is reduced, and the image plane characteristics deteriorate over the entire zoom range.

Further, the zoom ratio in zooming of the third subgroup FP2 becomes small, the amount of movement of the second lens group L2 for gaining the zoom ratio becomes large, and the total length of the lens at the telephoto end becomes long, which is not preferable.

If the interval DW4 becomes smaller than the lower limit of the conditional expression (6), interference with the third subgroup FP2 occurs in the focusing of the second subgroup FN from infinity to the closest distance, which is not preferable. In order to realize focusing to the closest distance, it is necessary to strengthen the refractive power of the second subgroup FN, which increases the eccentric sensitivity of the second subgroup FN and affects the assembly, which is not preferable.

The conditional expression (7) defines the distance DW2 between the second lens group L2 and the first subgroup FP1 at the wide-angle end when focusing at infinity. When the interval DW2 becomes larger than the upper limit of the conditional expression (7), the amount of movement of the second lens group and the first subgroup FP1 can be sufficiently secured when focusing to the closest distance, but the second subgroup FN and the first subgroup FN The distance from the three subgroup FP2 becomes narrower. As a result, the second subgroup FN and the third subgroup FP2 tend to interfere with each other during focusing, which is not preferable.

Further, since the second subgroup FN having a negative refractive power is arranged on the image side at the wide-angle end, the incident angle of the light flux on the image plane becomes tight, which is not preferable. In order to relax the incident angle, it is necessary to move the second subgroup FN toward the object side, which is not preferable because the total length of the lens at the wide-angle end becomes long.

If the DW2 becomes smaller than the lower limit of the conditional expression (7), it becomes difficult to secure a sufficient amount of movement of the first subgroup FP1 during focusing from infinity to a close distance. As a result, it becomes difficult to focus on an object located at a short distance, which is not preferable.

The conditional expression (8) defines the ratio of the refractive powers of the first lens group L1 and the second lens group L2. When the negative refractive power of the first lens group L1 with respect to the second lens group L2 becomes stronger beyond the upper limit of the conditional expression (8), the amount of movement of the second lens group L2 in zooming becomes large and the total length of the lens at the telephoto end increases. Increase. Further, the Petzval sum becomes small and the curvature of field tends to be under, which is not preferable.

When the negative refractive power of the first lens group L1 with respect to the second lens group L2 becomes weaker than the lower limit of the conditional expression (8), the total length of the lens tends to be shortened, but the first lens group L1 becomes radial. It is not preferable because it expands and the whole system becomes large. Further, the Petzval sum becomes large and the curvature of field tends to be over, which is not preferable.

The conditional expression (9) defines the amount of movement of the first lens group L1 in zooming. If the amount of movement of the first lens group L1 exceeds the upper limit of the conditional expression (9), the total length of the lens at the telephoto end increases and the entire system becomes large, which is not preferable. Further, while keeping the total length of the lens constant at the telephoto end, if the upper limit is exceeded, the total length of the lens at the wide-angle end becomes shorter and the effective diameter of the front lens becomes smaller, but the refractive power of the first lens group L1 becomes stronger and therefore the image plane. The curvature is under, which is not preferable.

When the amount of movement of the first lens group L1 becomes smaller than the lower limit of the conditional expression (9), the total length of the lens at the telephoto end becomes short, but the total length of the lens at the wide-angle end becomes large, and the first lens group L1 and the aperture stop Since the distance from SP1 becomes large, the effective diameter of the front lens becomes large, which is not preferable.

The conditional expression (10) defines the ratio of the amount of movement of the second lens group L2 and the first subgroup FP1 during zooming. If the amount of movement of the second lens group L2 exceeds the upper limit of the conditional expression (10), the total length of the lens becomes long at the telephoto end, which is not preferable. If the amount of movement of the second lens group L2 becomes smaller than the lower limit of the conditional expression (10), the entire system can be easily miniaturized, but the second lens group L2 and the first subgroup FP1 are at the telephoto end. It is not preferable because it tends to interfere. Further, it is not preferable because the second lens group L2 and the first subgroup FP1 are likely to interfere with each other in focusing at the telephoto end at the closest distance from infinity.

The conditional expression (11) defines the ratio of the movement amount of the second subgroup FN to the movement amount of the third subgroup FP2 in zooming. If the amount of movement of the second subgroup FN exceeds the lower limit of the conditional expression (11), the total length of the lens becomes long at the telephoto end, which is not preferable. When the amount of movement of the third subgroup FP2 exceeds the upper limit of the conditional expression (11), the scaling factor becomes larger in the third subgroup FP2, and the lens group on the object side of the third subgroup FP2 becomes larger. The amount of movement in zooming can be reduced.

However, since the third subgroup FP2 is located on the object side at the wide-angle end, it easily interferes with the second subgroup FN, which is not preferable. In order to avoid interference, it is necessary to increase the total length of the lens at the wide-angle end, which is not preferable because the entire system becomes large.

The conditional expression (12) defines the lens shape of the second subgroup FN. The conditional expression (12) means that the second subgroup FN is composed of a meniscus-shaped lens having a convex surface facing the image side. The second subgroup FN is a meniscus-shaped lens with a convex surface facing the image side, so that it is arranged concentrically with off-axis rays. As a result, when focusing from infinity to the closest distance, the concentric state with the off-axis light beam does not change even after moving to the image side, and the image plane fluctuation due to focusing is reduced.

When the lens shape changes beyond the upper limit of the conditional expression (12), the shape becomes a shape in the direction in which the difference between the curvature of the lens surface on the object side and the curvature of the lens surface on the image side disappears, and the lens shape with the first lens group L1. This is not preferable because the symmetry of the lens is broken and a lot of coma is generated. When the lens shape changes beyond the lower limit of the conditional expression (12), the difference between the curvature of the lens surface on the object side and the curvature of the lens surface on the image side becomes large, and the symmetry of the lens shape with the first lens group L1. Will improve and coma will be reduced. However, the negative refractive power becomes strong, the Petzval sum becomes large in the positive direction, and the curvature of field becomes excessive, which is not preferable.

The conditional expression (13) defines the lens shape of the first subgroup FP1. The conditional expression (13) means that the first subgroup FP1 has a meniscus shape or a biconvex shape with a convex surface facing the image side. If the first subgroup FP1 has a meniscus shape with a convex surface facing the image side, the second subgroup FN has a lens shape with a concave surface facing the image side, so that the second subgroup FN and the first subgroup when retracted. The air spacing of the FP1 can be made closer, which is effective for miniaturization of the entire system.

When the lens shape changes beyond the upper limit of the conditional expression (13), the positive refractive power of the first subgroup FP1 becomes weak. When the refractive power of the first subgroup FP1 becomes weaker, the positive refractive power of the third subgroup FP2, which is a lens group having the same positive refractive power as the first subgroup FP1, becomes stronger. It is not preferable because the thickness becomes thick and the collapsible thickness becomes thick.

When the lens shape changes beyond the lower limit of the conditional expression (13), the lens surface on the object side of the second subgroup FN becomes a biconvex shape with a strong curvature toward the object side or a meniscus shape with the convex surface facing the object side. Become. A lens shape in which the convex shape does not face the image side of the second subgroup FN is not preferable because a wasted space is created between the first subgroup FP1 and the second subgroup FN at the time of collapsing and the collapsing thickness becomes thick.

Conditional expression (14) defines the lens shape of the third subgroup FP2. The conditional expression (14) means that it has a meniscus shape or a biconvex shape with a convex surface facing the image side. If the curvature of the lens surface on the object side of the third subgroup FP2 exceeds the upper limit of the conditional expression (14), the curvature of field becomes good at the telephoto end, but the curvature of field increases at the wide-angle end. Not preferable. Specifically, at the wide-angle end, the curvature of field is under at a low image height, and the curvature of field is over at a high image height.

When the curvature of the lens surface on the object side of the third subgroup FP2 exceeds the lower limit of the conditional expression (14) and the concave surface is directed toward the object side, the curvature of field improves at the wide-angle end, but the image at the telephoto end. The curvature of field is over, which is not preferable. Further, if the lens shape of the third subgroup FP2 having a large effective diameter has a meniscus shape with a tight curvature, a space is required in the peripheral portion due to the structure, and the entire system becomes large, which is not preferable.

Conditional expression (15) defines the ratio of the length from the aperture stop SP1 at the wide-angle end to the lens surface of the first subgroup FP1 on the object side and the length from the aperture stop SP1 at the wide-angle end to the imaging point. Here, when determining the length from the aperture diaphragm SP1 to the imaging point, if there is a filter or the like having no refractive power between the final lens surface and the image plane, those lengths are the lengths converted to air. ..

When the first subgroup FP1 approaches the imaging point (image plane) beyond the upper limit of the conditional expression (15), the distance between the second lens group L2 and the first subgroup FP1 is in the direction of separation. Therefore, there is no interference in focusing from infinity to the closest distance, but the distance between the second subgroup FN and the third subgroup FP2 is narrowed, so that the amount of movement of the second subgroup FN during focusing is limited. Attempting to avoid this limitation is not preferable because the total length of the lens at the wide-angle end becomes long.

If the first subgroup FP1 moves away from the imaging point beyond the lower limit of the conditional expression (15), the second lens group L2 and the first subgroup FP1 are likely to interfere with each other in focusing from infinity to the closest distance. Not preferred.

Conditional expression (16) defines the ratio of the length from the aperture stop SP1 at the wide-angle end to the lens surface of the second subgroup FN on the object side and the length from the aperture stop SP1 at the wide-angle end to the imaging point. If the second subgroup FN approaches the imaging point beyond the upper limit of the conditional expression (16), the amount of space to move during focusing becomes small, which is not preferable. In addition, it is necessary to strengthen the refractive power of the second subgroup FN in order to reduce the size of the entire system, and as a result, the angle of incidence of the light beam on the image plane becomes tight, or the angle of incidence is finally relaxed. It is not preferable because the refractive power of the lens group (third subgroup FP2) becomes strong and the lens group thickness becomes thick.

When the second subgroup FN approaches the aperture stop SP1 beyond the lower limit of the conditional expression (16), a margin of space for movement during focusing can be secured, but the symmetry between the first lens group L1 and the aperture stop SP1 is broken. , It is not preferable because a lot of coma aberration occurs.

The conditional expression (17) defines the amount of movement when the first lens group L1 moves toward the image side in a convex locus in zooming. If the amount of movement of the first lens group L1 toward the object increases beyond the upper limit of the conditional expression (17), the total length of the lens at the telephoto end becomes long, which is not preferable. If the amount of movement of the first lens group L1 toward the image side exceeds the lower limit of the conditional expression (17), the total length of the lens becomes long at the wide-angle end and the effective diameter of the front lens becomes large, which is not preferable.

Conditional expression (18) Defines the refractive index of the material of the lens on the most object side of the first lens group L1. When the refractive index becomes large beyond the upper limit of the conditional expression (18), the existing glass material becomes a glass material having a small Abbe number, and the glass material of the positive lens in the first lens group L1 for achromatication decreases. It is not preferable because it is difficult to erase the color. When the refractive index becomes smaller than the lower limit of the conditional expression (18), there are many glass materials for achromatication, but since the refractive index becomes low, the size of the effective diameter of the front lens becomes large, which is not preferable.

In each embodiment, it is preferable that the numerical range of the conditional expressions (2) to (18) is as follows.

-0.85 <MfFP1 / MfFN <-0.05 ... (2a)
-1.50 <fP1 / fN <-0.40 ... (3a)
-1.90 <fP2 / fN <-0.55 ... (4a)
0.50 <fP2 / fP1 <1.00 ... (5a)
0.15 <DW4 / fW <0.90 ... (6a)
0.20 <DW2 / fW <0.80 ... (7a)
-1.30 <f1 / f2 <-0.65 ... (8a)
-1.30 <M1 / fW <-0.30 ... (9a)
1.01 <M2 / MFP1 <1.40 ... (10a)
-11.00 <MFN / MFP2 <-2.50 ... (11a)
1.005 <(FNR2 + FNR1) / (FNR2-FNR1) <12.000
... (12a)
0.50 <(FP1R2 + FP1R1) / (FP1R2-FP1R1) <4.50
... (13a)
0.25 <(FP2R2 + FP2R1) / (FP2R2-FP2R1) <2.00
... (14a)
0.08 <DSP1 / DSIP <0.50 ... (15a)
0.25 <DSN / DSNP <0.65 ... (16a)
−0.40 <M1a / M1b <0.00 ・ ・ ・ (17a)
1.930 <G1Nd <2.030 ... (18a)

Further, more preferably, when the numerical range of the conditional expressions (2a) to (18a) is set as follows, the effect meant by each of the conditional expressions described above can be obtained to the maximum.

-0.70 <MfFP1 / MfFN <-0.10 ... (2b)
-1.30 <fP1 / fN <-0.45 ... (3b)
-1.85 <fP2 / fN <-0.60 ... (4b)
0.60 <fP2 / fP1 <0.90 ... (5b)
0.20 <DW4 / fW <0.80 ... (6b)
0.25 <DW2 / fW <0.60 ... (7b)
-1.20 <f1 / f2 <-0.70 ... (8b)
-1.25 <M1 / fW <-0.33 ... (9b)
1.02 <M2 / MFP1 <1.30 ... (10b)
-10.30 <MFN / MFP2 <-3.00 ... (11b)
1.01 <(FNR2 + FNR1) / (FNR2-FNR1) <9.50
... (12b)
0.70 <(FP1R2 + FP1R1) / (FP1R2-FP1R1) <4.00
... (13b)
0.30 <(FP2R2 + FP2R1) / (FP2R2-FP2R1) <1.65
... (14b)
0.10 <DSP1 / DSIP <0.45 ... (15b)
0.30 <DSN / DSNP <0.60 ... (16b)
−0.385 <M1a / M1b <0.00 ・ ・ ・ (17b)
1.950 <G1Nd <2.010 ... (18b)

In each embodiment, by configuring each element as described above, a zoom lens is obtained which is easy to focus to the closest distance while the whole system is compact and has high optical performance. When aiming to reduce the effective diameter of the first lens group in a negative lead zoom lens, the refractive power of the first lens group L1 having a negative refractive power becomes stronger, so the first lens group is composed of three lenses. Is good.

For miniaturization, two lens configurations, a negative lens and a positive lens, in which the number of lenses is reduced can be considered. However, if the refractive power of the first lens group is increased for compactification, the curvature of the negative lens becomes tight. Further, since the distance between the two lenses is required to improve the spherical aberration and the image plane characteristics, the thickness of the first lens group is required to some extent even in the case of the two lens configuration. Therefore, by dividing the refractive power of the negative lens in the first lens group and using two negative lenses, it becomes easy to reduce the size in the radial direction while maintaining good optical performance.

In order to satisfactorily correct various aberrations, it is preferable that the first lens group L1 is composed of three lenses, a negative lens 11, a negative lens 12, and a positive lens 13, in this order from the object side to the image side. Further, the negative lens 11 on the most object side uses a high refractive index material, and the lens surface of the negative lens 12 having a smaller lens diameter than the negative lens 11 is made aspherical, so that the aspherical surface can be easily processed. High optical performance can be obtained while reducing the size of the entire system.

Further, the first lens 11 is preferably in a meniscus shape with a concave surface on the image side. By making the second partial group FN of the negative refractive power a single lens having a meniscus shape with the convex surface facing the image side, the shape is symmetrical with respect to the first lens L1 of the negative refractive power and the aperture stop SP1. The coma aberration is corrected well.

It is desirable that the second lens group L2 has a positive refractive power. At the wide-angle end, the axial light beam becomes a divergent light beam when it passes through the first lens group L1 having a negative refractive power, but the lens group located closest to the object side of the rear group following the first lens group L1 has a positive refractive power. As a result, it has a converging effect on the light beam and reduces the effective diameter of the lens in the rear group.

Further, it is desirable that the second lens group L1 has a positive lens 21, a positive lens 22, and a negative lens 23 in this order from the object side to the image side, and the positive lens 21 has an aspherical lens surface. By having the positive lens 21 on the most object side having a large effective diameter having an aspherical lens surface, it is easy to satisfactorily correct spherical aberration and coma aberration in the entire zoom region. Further, the third lens group is preferably composed of one positive lens.

When zooming from the wide-angle end to the telephoto end, the second lens group L2, the first subgroup FP1, and the second subgroup FN all move to the object side. Further, when zooming from the wide-angle end to the telephoto end, the third subgroup FP2 moves to the image side. According to this, a high scaling ratio can be effectively obtained.

Next, an embodiment of a digital camera (optical device) using the zoom lens of the present invention as an imaging optical system will be described with reference to FIG. In FIG. 19, 20 is a digital camera body, 21 is an image pickup optical system composed of the zoom lenses of the above-described embodiments, 22 is an image pickup element such as a CCD that receives a subject image by the image pickup optical system 21, and 23 is an image pickup element. This is a recording means for recording a subject image received by 22. Reference numeral 24 denotes a finder for observing a subject image displayed on a display element (not shown).

The display element is composed of a liquid crystal panel or the like, and a subject image formed on the image pickup element 22 is displayed. Reference numeral 24 denotes a liquid crystal display panel having a function equivalent to that of a finder.

By applying the zoom lens of the present invention to an image pickup device such as a digital camera in this way, a compact image pickup device having high optical performance is realized.

Next, numerical data 1 to 6 corresponding to Examples 1 to 6 of the present invention are shown. In each numerical data, i indicates the order of the surfaces from the object side, ndi and ri are the radius of curvature of the lens surface, di is the lens wall thickness and air spacing between the i-th surface and the i + 1-plane, ndi, νdi. Indicates the refractive index and Abbe number for the d-line, respectively. In the numerical data 3 and 4, the interval value is marked with a “−” sign because the aperture is stopped from the object surface, and the lens is counted in this order.

Further, the two surfaces on the most image side are glass materials such as a face plate. Further, k is a conical constant, and A4, A6, A8, and A10 are aspherical coefficients. The aspherical shape is when the displacement in the optical axis direction at the height h from the optical axis is x with respect to the surface apex.
x = (h ² / R) / [1 + {1- (1 + k) (h / R) ² } ^1/2 ] + A4h ⁴ + A6h ⁶ + A8h ⁸ + A10h ¹⁰
It is represented by. However, R is the radius of curvature of the paraxial axis.

The numerical value "E ± XX" means "x10 ^{± XX} ". Further, the portion where the distance d of each optical surface is (variable) changes during zooming, and the surface distance according to the focal length is described in the attached table. Tables 1A and 1B show the calculation results of each conditional expression based on the lens data of the numerical data 1 to 6 described below.

[Numerical data 1]
Unit mm

Surface data Surface number rd nd ν d
1 76.577 0.85 1.95375 32.3
2 15.499 4.26
3 * 65.924 1.40 1.53160 55.8
4 * 28.208 0.15
5 21.601 2.24 1.95906 17.5
6 43.976 (variable)
7 (Aperture) (SP1) ∞ (Variable)
8 * 13.639 2.21 1.69350 53.2
9 * -182.217 1.11
10 20.617 3.08 2.00100 29.1
11 -11.603 0.60 1.85478 24.8
12 8.846 2.00
13 (SP2) ∞ (variable)
14 328.008 2.08 1.74330 49.3
15 * -26.016 2.70
16 -25.700 0.70 1.83400 37.2
17 -77.285 (variable)
18 -340.267 3.60 1.53160 55.8
19 * -24.859 (variable)
20 ∞ 1.30 1.51633 64.1
21 ∞ 0.50
Image plane ∞

Aspherical data third surface
K = 0.00000e + 000 A 4 = -1.01756e-005 A 6 = -2.307078e-007 A 8 = 9.83465e-010

4th side
K = 0.00000e + 000 A 4 = -2.29560e-005 A 6 = -2.67140e-007 A 8 = 1.06706e-009 A10 = -1.01510e-013

8th page
K = 0.00000e + 000 A 4 = -6.93027e-005 A 6 = -3.22498e-007 A 8 = -5.41392e-009

Side 9
K = 0.00000e + 000 A 4 = 2.49446e-005

Page 15
K = 0.00000e + 000 A 4 = 4.40364e-007 A 6 = -3.52863e-008 A 8 = -3.87550e-010

Page 19
K = 0.00000e + 000 A 4 = 5.62098e-005 A 6 = -1.45256e-007 A 8 = 2.55362e-010

Various data Zoom ratio 2.83
Wide-angle end Middle 1 Middle 2 Telephoto end Focal length 15.45 22.75 26.04 43.70
F number 2.89 3.60 4.00 5.77
Half angle of view (degrees) 38.02 30.56 27.29 17.09
Total lens length 69.79 66.41 66.81 75.34
BF 8.65 7.97 7.57 4.69

d 6 20.96 10.52 7.89 2.02
d 7 1.99 1.93 1.79 0.10
d13 5.48 6.63 7.18 10.31
d17 5.72 12.38 15.40 31.23
d19 7.30 6.61 6.21 3.33

At close focus (distance from surface number 1 to object point)
50mm 80mm 80mm 200mm
d 6 20.96 10.52 7.89 2.02
d 7 1.99 1.93 1.79 0.10
d13 3.87 5.85 6.23 9.10
d15 7.70 9.03 10.13 7.20
d17 2.33 6.83 8.92 27.94
d19 7.30 6.61 6.21 3.33
d21 0.50 0.50 0.50 0.50

Focal length
1 1 -29.09
2 8 25.47
3 14 91.30
4 18 50.25

[Numerical data 2]
Unit mm

Surface data Surface number rd nd ν d
1 74.111 0.85 2.00100 29.1
2 15.977 4.79
3 * 61.391 1.20 1.58573 59.7
4 * 25.653 0.56
5 23.402 2.60 1.95906 17.5
6 58.274 (variable)
7 (Aperture) (SP1) ∞ (Variable)
8 * 15.590 3.00 1.76802 49.2
9 * -144.212 1.79
10 21.549 2.60 1.95375 32.3
11 -17.690 0.60 1.85478 24.8
12 10.031 2.74
13 (SP2) ∞ (variable)
14 -59.298 1.20 1.95375 32.3
15 -21.585 3.65
16 -20.917 1.55 1.67300 38.1
17 -13.219 0.50 1.72825 28.5
18 -49.907 (variable)
19 1551.093 4.00 1.77250 49.5
20 * -32.506 (variable)
21 ∞ 1.30 1.51633 64.1
22 ∞ 0.50
Image plane ∞

Aspherical data third surface
K = 0.00000e + 000 A 4 = -2.29628e-005 A 6 = 2.45167e-008 A 8 = -3.64727e-010 A10 = 1.13474e-012

4th side
K = 0.00000e + 000 A 4 = -3.90911e-005 A 6 = 2.88273e-008 A 8 = -7.44512e-010 A10 = 2.53874e-012

8th page
K = -1.41037e-002 A 4 = -3.75568e-005 A 6 = -1.22940e-007 A 8 = 1.34745e-010

Side 9
K = 0.00000e + 000 A 4 = 1.58555e-005

20th page
K = 0.00000e + 000 A 4 = 2.25597e-005 A 6 = -3.57346e-008 A 8 = 3.62029e-011

Various data Zoom ratio 2.83
Wide-angle end Middle 1 Middle 2 Telephoto end Focal length 15.45 21.71 26.07 43.70
F number 2.88 3.50 4.00 5.77
Half angle of view (degrees) 38.01 31.75 27.26 17.09
Total lens length 73.53 70.70 71.46 81.81
BF 9.53 9.28 9.04 6.94

d 6 22.91 11.98 7.61 2.09
d 7 0.00 1.42 1.92 0.10
d13 4.02 4.37 4.71 6.70
d18 5.44 12.01 16.55 34.35
d20 8.18 7.93 7.68 5.58

At close focus (distance from surface number 1 to object point)
50mm 80mm 80mm 200mm
d 6 22.91 11.98 7.61 2.09
d 7 0.00 1.42 1.92 0.10
d13 2.28 3.59 3.69 5.45
d15 8.75 9.53 10.96 8.09
d18 2.09 6.91 10.26 31.16
d20 8.18 7.93 7.68 5.58
d22 0.50 0.50 0.50 0.50

Focal length
1 1 -29.13
2 8 26.77
3 14 112.97
4 19 41.26

[Numerical data 3]
Unit mm

Surface data Surface number rd nd ν d
1 115.898 1.00 1.95375 32.3
2 16.600 5.00
3 * 282.648 1.20 1.58573 59.7
4 * 24.916 0.30
5 22.736 2.70 1.95906 17.5
6 53.461 (variable)
7 (SP2) ∞ (variable)
8 * 19.620 3.65 1.85135 40.1
9 * -102.233 2.00
10 26.476 3.60 1.88300 40.8
11 -29.098 0.60 1.85478 24.8
12 12.091 3.47
13 (Aperture) (SP1) ∞ (Variable)
14 -86.525 0.70 1.68893 31.1
15 16.587 3.20 1.88300 40.8
16 -27.502 (variable)
17 * -34.234 1.00 1.69350 53.2
18 -295.311 (variable)
19 58.601 4.90 1.53160 55.8
20 * -31.375 (variable)
21 ∞ 1.30 1.51633 64.1
22 ∞ 0.50
Image plane ∞

Aspherical data third surface
K = 0.00000e + 000 A 4 = 1.63022e-005 A 6 = -1.86018e-008 A 8 = -1.34343e-010

4th side
K = 0.00000e + 000 A 4 = 6.64320e-006 A 6 = -4.89576e-008 A 8 = -1.46214e-010

8th page
K = -1.41037e-002 A 4 = -2.211133e-005 A 6 = -2.45947e-008

Side 9
K = 0.00000e + 000 A 4 = 5.90844e-006

Page 17
K = 0.00000e + 000 A 4 = -2.18571e-005 A 6 = 7.39569e-008 A 8 = -2.84554e-009

20th page
K = 0.00000e + 000 A 4 = 3.00769e-005 A 6 = -2.40015e-008 A 8 = 2.87542e-011

Various data Zoom ratio 2.85
Wide-angle end Middle 1 Middle 2 Telephoto end Focal length 15.45 16.16 26.00 44.00
F number 2.06 2.20 3.50 5.78
Half angle of view (degrees) 38.01 39.73 27.33 16.98
Total lens length 76.88 76.85 81.58 95.60
BF 9.44 9.38 7.95 4.70

d 6 16.71 15.80 8.48 2.45
d 7 1.25 1.07 -0.58 -0.93
d13 3.89 4.03 5.72 7.60
d16 4.54 4.71 6.89 10.00
d18 7.72 8.53 19.80 38.45
d20 8.09 8.02 6.59 3.34

At close focus (distance from surface number 1 to object point)
50mm 80mm 80mm 200mm
d 6 16.71 15.80 8.48 2.45
d 7 1.25 1.07 -0.58 -0.93
d13 2.17 3.54 4.65 5.99
d16 10.24 9.42 15.29 15.32
d18 3.74 4.31 12.47 34.74
d20 8.09 8.02 6.59 3.34
d22 0.50 0.50 0.50 0.50

Focal length
1 1 -22.00
2 8 29.70
3 14 27.95
4 17 -55.92
5 19 39.18

[Numerical data 4]
Unit mm

Surface data Surface number rd nd ν d
1 117.391 1.00 2.00100 29.1
2 19.846 5.00
3 * 332.714 1.20 1.58573 59.7
4 * 40.910 0.30
5 28.763 2.80 1.95906 17.5
6 76.299 (variable)
7 (SP2) ∞ (variable)
8 * 19.647 4.09 1.85135 40.1
9 * -150.119 1.58
10 23.758 3.36 1.88300 40.8
11 -41.943 0.90 1.85478 24.8
12 11.832 3.47
13 (Aperture) (SP1) ∞ (Variable)
14 -80.896 1.00 1.69895 30.1
15 22.724 3.42 1.88300 40.8
16 -30.315 (variable)
17 * -23.402 1.00 1.69350 53.2
18 * -91.963 (variable)
19 232.943 5.20 1.59201 67.0
20 * -28.000 (variable)
21 ∞ 1.30 1.51633 64.1
22 ∞ 0.50
Image plane ∞

Aspherical data third surface
K = 0.00000e + 000 A 4 = -2.70634e-008 A 6 = 4.26310e-008 A 8 = -5.96223e-011

4th side
K = 0.00000e + 000 A 4 = -2.80012e-006 A 6 = 4.34912e-008 A 8 = -1.02259e-010

8th page
K = -1.41037e-002 A 4 = -1.78164e-005 A 6 = -2.62673e-008

Side 9
K = 0.00000e + 000 A 4 = 3.57156e-006

Page 17
K = 0.00000e + 000 A 4 = 3.78072e-005 A 6 = 3.12691e-007 A 8 = -2.44431e-009

Page 18
K = 0.00000e + 000 A 4 = 4.87963e-005 A 6 = 1.83684e-007 A 8 = -1.36312e-009

20th page
K = 0.00000e + 000 A 4 = 2.07848e-005 A 6 = -4.32159e-008 A 8 = 5.20787e-011

Various data Zoom ratio 2.83
Wide-angle end Middle 1 Middle 2 Telephoto end Focal length 17.90 25.26 30.07 50.67
F number 2.06 2.52 3.00 5.05
Half angle of view (degrees) 34.01 28.00 24.07 14.85
Total lens length 84.12 81.28 81.95 90.36
BF 11.77 10.85 10.11 6.43

d 6 23.02 13.73 10.20 2.00
d 7 1.98 0.57 -0.08 -0.99
d13 3.61 5.55 6.65 9.99
d16 2.70 4.62 5.80 10.00
d18 6.72 11.63 14.94 28.61
d20 10.41 9.49 8.76 5.08

At close focus (distance from surface number 1 to object point)
50mm 80mm 80mm 200mm
d 6 23.02 13.73 10.20 2.00
d 7 1.98 0.57 -0.08 -0.99
d13 1.56 4.56 5.34 8.20
d16 8.52 12.22 15.68 16.72
d18 2.96 5.03 6.36 23.68
d20 10.41 9.49 8.76 5.08
d22 0.50 0.50 0.50 0.50

Focal length
1 1 -31.71
2 8 30.40
3 14 34.72
4 17 -45.53
5 19 42.54

[Numerical data 5]
Unit mm

Surface data Surface number rd nd ν d
1 72.579 0.70 2.00100 29.1
2 20.326 4.50
3 * -74.405 1.20 1.58313 59.4
4 * 49.343 0.88
5 23.291 2.10 1.95906 17.5
6 44.181 (variable)
7 (Aperture) (SP1) ∞ (Variable)
8 * 18.232 3.00 1.77250 49.5
9 * -85.005 1.60
10 25.246 2.80 1.95375 32.3
11 -17.363 0.60 1.85478 24.8
12 12.242 2.74
13 (SP2) ∞ (variable)
14 148.748 2.10 1.88300 40.8
15 -25.477 (variable)
16 -16.543 0.70 1.83400 37.2
17 -2056.249 (variable)
18 * 417.602 5.40 1.59201 67.0
19 * -22.351 (variable)
20 ∞ 1.30 1.51633 64.1
21 ∞ 0.50
Image plane ∞

Aspherical data third surface
K = 0.00000e + 000 A 4 = 6.84946e-005 A 6 = -9.84114e-007 A 8 = 7.17643e-009 A10 = -1.96317e-011

4th side
K = 0.00000e + 000 A 4 = 8.36427e-005 A 6 = -1.00679e-006 A 8 = 7.93824e-009 A10 = -2.23888e-011

8th page
K = -1.41037e-002 A 4 = -3.34581e-005 A 6 = -1.03774e-007 A 8 = 1.69118e-010

Side 9
K = 0.00000e + 000 A 4 = 9.20213e-006

Page 18
K = 0.00000e + 000 A 4 =-8.59285e-006

Page 19
K = 0.00000e + 000 A 4 = 3.27888e-005 A 6 = -6.39636e-008 A 8 = 1.13443e-010

Various data Zoom ratio 2.83
Wide-angle end Middle 1 Middle 2 Telephoto end Focal length 17.92 24.54 30.03 50.67
F number 2.88 3.50 4.00 5.77
Half angle of view (degrees) 33.98 28.70 24.10 14.85
Total lens length 73.73 71.59 72.47 82.15
BF 7.74 7.70 7.56 5.19

d 6 21.54 12.59 8.20 2.14
d 7 0.00 0.87 1.30 0.86
d13 7.83 8.38 8.90 11.09
d15 4.51 4.90 5.18 5.78
d17 3.78 8.81 13.01 28.77
d19 6.38 6.34 6.20 3.83

At close focus (distance from surface number 1 to object point)
50mm 80mm 80mm 200mm
d 6 21.54 12.59 8.20 2.14
d 7 0.00 0.87 1.30 0.86
d13 6.62 7.90 8.30 10.41
d15 7.63 8.01 8.94 8.00
d17 1.87 6.19 9.85 27.23
d19 6.38 6.34 6.20 3.83
d21 0.50 0.50 0.50 0.50

Focal length
1 1 -29.12
2 8 26.27
3 14 24.77
4 16 -20.00
5 18 36.00

[Numerical data 6]
Unit mm

Surface data Surface number rd nd ν d
1 230.579 0.70 1.95375 32.3
2 18.261 4.50
3 -316.966 1.20 1.58313 59.4
4 * 100.965 1.20
5 28.470 1.90 1.98738 16.4
6 58.052 (variable)
7 (Aperture) (SP1) ∞ (Variable)
8 * 15.913 3.20 1.76802 49.2
9 * -154.619 1.90
10 19.458 2.30 1.91082 35.3
11 -61.067 0.60 1.85478 24.8
12 10.431 2.74
13 (SP2) ∞ (variable)
14 -32.868 1.00 1.80400 46.6
15 -19.220 3.04
16 -14.129 0.70 1.68893 31.1
17 -17.542 (variable)
18 -122.530 2.80 1.53160 55.8
19 * -28.770 (variable)
20 ∞ 1.30 1.51633 64.1
21 ∞ 0.50
Image plane ∞

Aspherical data 4th surface
K = 0.00000e + 000 A 4 = -3.58677e-006 A 6 = 4.41917e-008 A 8 = -4.79957e-010 A10 = 1.60314e-012

8th page
K = -1.41037e-002 A 4 = -2.53994e-005 A 6 = -2.06589e-008 A 8 = -2.25174e-010

Side 9
K = 0.00000e + 000 A 4 = 1.51133e-005

Page 19
K = 0.00000e + 000 A 4 = 3.59260e-005 A 6 = -4.01298e-008 A 8 = -1.00406e-011

Various data Zoom ratio 2.83
Wide-angle end Middle 1 Middle 2 Telephoto end Focal length 17.92 25.27 30.36 50.67
F number 2.88 3.53 4.00 5.77
Half angle of view (degrees) 33.98 27.99 23.87 14.85
Total lens length 76.23 73.86 74.60 84.25
BF 9.18 7.65 6.94 4.70

d 6 23.63 12.63 8.14 1.83
d 7 0.00 1.47 1.94 0.00
d13 2.50 3.09 3.35 3.43
d17 13.14 21.24 26.45 46.50
d19 7.82 6.29 5.58 3.34

At close focus (distance from surface number 1 to object point)
100mm 120mm 120mm 250mm
d 6 23.63 12.63 8.14 1.83
d 7 0.00 1.47 1.94 0.00
d13 1.34 2.10 2.05 2.37
d15 9.53 12.62 15.32 13.09
d17 7.80 12.64 15.47 37.51
d19 7.82 6.29 5.58 3.34
d21 0.50 0.50 0.50 0.50

Focal length
1 1 -29.14
2 8 27.56
3 14 107.46
4 18 70.00

L0 Zoom lens L1 1st lens group L2 2nd lens group FP1 1st subgroup FN 2nd subgroup FP2 3rd subgroup

Claims (21)

The first lens group of negative power, the second lens group of positive power, the first part group of positive power, and the second part group of negative power arranged in order from the object side to the image side. It has a third subset of positive power, and the distance between the first lens group and the second lens group is shorter at the telephoto end than at the wide-angle end, and the distance between adjacent lens groups changes during zooming. In the zoom lens
When focusing from infinity to the closest distance, the first subgroup moves to the object side, and the second subgroup moves to the image side.
The amount of movement of the first lens group in zooming from the wide-angle end to the telephoto end is M1, the amount of movement of the second lens group in zooming from the wide-angle end to the telephoto end is M2 , and the focal length of the first lens group is f1. When the focal length of the second lens group is f2 ,
0.00 <M1 / M2 <1.00
-1.50 <f1 / f2 <-0.60
A zoom lens characterized by satisfying the conditional expression. The first lens group of negative power, the second lens group of positive power, the first part group of positive power, and the second part group of negative power arranged in order from the object side to the image side. It has a third subset of positive power, and the distance between the first lens group and the second lens group is shorter at the telephoto end than at the wide-angle end, and the distance between adjacent lens groups changes during zooming. In the zoom lens
When focusing from infinity to the closest distance, the first subgroup moves to the object side, and the second subgroup moves to the image side.
The movement amount of the first lens group in zooming from the wide-angle end to the telephoto end is M1, the movement amount of the second lens group in zooming from the wide-angle end to the telephoto end is M2, and the movement amount in focusing from infinity to the nearest distance is described above. When the movement amount of the second subgroup is MfFN and the movement amount of the first subgroup in focusing from infinity to the nearest distance is MfFP1.
0.00 <M1 / M2 <1.00
-1.00 <MfFP1 / MfFN <0.00
Satisfies the following conditional expressions and to Luz Murenzu. When the focal length of the first subgroup is fP1 and the focal length of the second subgroup is fN,
-1.80 <fP1 / fN <-0.30
The zoom lens according to claim 1 or 2, wherein the zoom lens satisfies the conditional expression. When the focal length of the second subgroup is fN and the focal length of the third subgroup is fP2,
-2.00 <fP2 / fN <-0.50
The zoom lens according to any one of claims 1 to 3, wherein the zoom lens satisfies the conditional expression. When the distance between the second subgroup and the third subgroup on the optical axis at the wide-angle end is DW4 and the focal length of the entire system at the wide-angle end is fW when focusing at infinity.
0.10 <DW4 / fW <1.00
The zoom lens according to any one of claims 1 to 4 , wherein the zoom lens satisfies the conditional expression. When the distance between the second lens group and the first subgroup on the optical axis at the wide-angle end is DW2 and the focal length of the entire system at the wide-angle end is fW when focusing at infinity.
0.10 <DW2 / fW <1.00
The zoom lens according to any one of claims 1 to 5 , wherein the zoom lens satisfies the conditional expression. The first lens group of negative power, the second lens group of positive power, the first part group of positive power, and the second part group of negative power arranged in order from the object side to the image side. It has a third subset of positive power, and the distance between the first lens group and the second lens group is shorter at the telephoto end than at the wide-angle end, and the distance between adjacent lens groups changes during zooming. In the zoom lens
When focusing from infinity to the closest distance, the first subgroup moves to the object side, and the second subgroup moves to the image side.
The amount of movement of the first lens group in zooming from the wide-angle end to the telephoto end is M1, the amount of movement of the second lens group in zooming from the wide-angle end to the telephoto end is M2, and the focal length of the entire system at the wide-angle end is fW. When
0.00 <M1 / M2 <1.00
-1.50 <M1 / fW <-0.20
Satisfies the following conditional expressions and to Luz Murenzu. The first lens group of negative power, the second lens group of positive power, the first part group of positive power, and the second part group of negative power arranged in order from the object side to the image side. It has a third subset of positive power, and the distance between the first lens group and the second lens group is shorter at the telephoto end than at the wide-angle end, and the distance between adjacent lens groups changes during zooming. In the zoom lens
When focusing from infinity to the closest distance, the first subgroup moves to the object side, and the second subgroup moves to the image side.
The amount of movement of the first lens group in zooming from the wide-angle end to the telephoto end is M1, the amount of movement of the second lens group in zooming from the wide-angle end to the telephoto end is M2, and the amount of movement of the second lens group in zooming from the wide-angle end to the telephoto end is M2. When the movement amount of the first subgroup is MFP1,
0.00 <M1 / M2 <1.00
1.00 <M2 / MFP1 <1.50
Satisfies the following conditional expressions and to Luz Murenzu. The first lens group of negative power, the second lens group of positive power, the first part group of positive power, and the second part group of negative power arranged in order from the object side to the image side. It has a third subset of positive power, and the distance between the first lens group and the second lens group is shorter at the telephoto end than at the wide-angle end, and the distance between adjacent lens groups changes during zooming. In the zoom lens
When focusing from infinity to the closest distance, the first subgroup moves to the object side, and the second subgroup moves to the image side.
The amount of movement of the first lens group in zooming from the wide-angle end to the telephoto end is M1, the amount of movement of the second lens group in zooming from the wide-angle end to the telephoto end is M2, and the amount of movement of the second lens group in zooming from the wide-angle end to the telephoto end is M2. When the movement amount of the second subgroup is MFN and the movement amount of the third subgroup in zooming from the wide-angle end to the telephoto end is MFP2.
0.00 <M1 / M2 <1.00
-12.00 <MFN / MFP2 <-2.00
Satisfies the following conditional expressions and to Luz Murenzu. When the radius of curvature of the lens surface on the most object side of the second subgroup is FNR1 and the radius of curvature of the lens surface on the most image side of the second subgroup is FNR2,
1.00 <(FNR2 + FNR1) / (FNR2-FNR1) <15.00
The zoom lens according to any one of claims 1 to 9 , wherein the zoom lens satisfies the conditional expression. The first lens group of negative power, the second lens group of positive power, the first part group of positive power, and the second part group of negative power arranged in order from the object side to the image side. It has a third subset of positive power, and the distance between the first lens group and the second lens group is shorter at the telephoto end than at the wide-angle end, and the distance between adjacent lens groups changes during zooming. In the zoom lens
When focusing from infinity to the closest distance, the first subgroup moves to the object side, and the second subgroup moves to the image side.
The zoom lens further has an aperture diaphragm and
The amount of movement of the first lens group in zooming from the wide-angle end to the telephoto end is M1, the amount of movement of the second lens group in zooming from the wide-angle end to the telephoto end is M2, and the amount of movement of the second lens group in zooming from the wide-angle end to the image plane. When the distance on the optical axis is DSPI and the distance on the optical axis from the aperture aperture at the wide-angle end to the lens surface on the object side of the first subgroup is DSP1.
0.00 <M1 / M2 <1.00
0.05 <DSP1 / DSIP <0.60
Satisfies the following conditional expressions and to Luz Murenzu. The first lens group of negative power, the second lens group of positive power, the first part group of positive power, and the second part group of negative power arranged in order from the object side to the image side. It has a third subset of positive power, and the distance between the first lens group and the second lens group is shorter at the telephoto end than at the wide-angle end, and the distance between adjacent lens groups changes during zooming. In the zoom lens
When focusing from infinity to the closest distance, the first subgroup moves to the object side, and the second subgroup moves to the image side.
The zoom lens further has an aperture diaphragm and
The amount of movement of the first lens group in zooming from the wide-angle end to the telephoto end is M1, the amount of movement of the second lens group in zooming from the wide-angle end to the telephoto end is M2, and the amount of movement of the second lens group in zooming from the wide-angle end to the image plane. When the distance on the optical axis is DSPI and the distance on the optical axis from the aperture aperture at the wide-angle end to the lens surface on the object side of the second segment group is DSN.
0.00 <M1 / M2 <1.00
0.20 <DSN / DSNP <0.70
Satisfies the following conditional expressions and to Luz Murenzu. The first lens group of negative power, the second lens group of positive power, the first part group of positive power, and the second part group of negative power arranged in order from the object side to the image side. It has a third subset of positive power, and the distance between the first lens group and the second lens group is shorter at the telephoto end than at the wide-angle end, and the distance between adjacent lens groups changes during zooming. In the zoom lens
When focusing from infinity to the closest distance, the first subgroup moves to the object side, and the second subgroup moves to the image side.
When zooming from the wide-angle end to the telephoto end, the first lens group moves in a convex locus toward the image side .
When the amount of movement of the first lens group in zooming from the wide-angle end to the telephoto end is M1, and the amount of movement of the second lens group in zooming from the wide-angle end to the telephoto end is M2.
0.00 <M1 / M2 <1.00
Satisfies the following conditional expressions and to Luz Murenzu. When the zoom position where the first lens group is located closest to the image side is set as the intermediate zoom position during zooming, the amount of movement of the first lens group from the wide-angle end to the intermediate zoom position is M1a, and the distance from the intermediate zoom position is telephoto. When the amount of movement of the first lens group at the edge is M1b,
-0.50 <M1a / M1b <0.00
The zoom lens according to claim 13 , wherein the zoom lens satisfies the conditional expression. The first lens group of negative power, the second lens group of positive power, the first part group of positive power, and the second part group of negative power arranged in order from the object side to the image side. It has a third subset of positive power, and the distance between the first lens group and the second lens group is shorter at the telephoto end than at the wide-angle end, and the distance between adjacent lens groups changes during zooming. In the zoom lens
When focusing from infinity to the closest distance, the first subgroup moves to the object side, and the second subgroup moves to the image side.
The first lens group is composed of three lenses .
When the amount of movement of the first lens group in zooming from the wide-angle end to the telephoto end is M1, and the amount of movement of the second lens group in zooming from the wide-angle end to the telephoto end is M2.
0.00 <M1 / M2 <1.00
This to satisfy the conditional expression, features and be Luz Murenzu. The first lens group of negative power, the second lens group of positive power, the first part group of positive power, and the second part group of negative power arranged in order from the object side to the image side. It has a third subset of positive power, and the distance between the first lens group and the second lens group is shorter at the telephoto end than at the wide-angle end, and the distance between adjacent lens groups changes during zooming. In the zoom lens
When focusing from infinity to the closest distance, the first subgroup moves to the object side, and the second subgroup moves to the image side.
The amount of movement of the first lens group in zooming from the wide-angle end to the telephoto end is M1, the amount of movement of the second lens group in zooming from the wide-angle end to the telephoto end is M2, and the most object in the first lens group. When the refractive index of the material of the lens arranged on the side is G1Nd,
0.00 <M1 / M2 <1.00
1.920 <G1Nd <2.060
Satisfies the following conditional expressions and to Luz Murenzu. The first lens group of negative power, the second lens group of positive power, the first part group of positive power, and the second part group of negative power arranged in order from the object side to the image side. It has a third subset of positive power, and the distance between the first lens group and the second lens group is shorter at the telephoto end than at the wide-angle end, and the distance between adjacent lens groups changes during zooming. In the zoom lens
When focusing from infinity to the closest distance, the first subgroup moves to the object side, and the second subgroup moves to the image side.
The first lens group is composed of a negative lens, a negative lens, and a positive lens arranged in order from the object side to the image side .
When the amount of movement of the first lens group in zooming from the wide-angle end to the telephoto end is M1, and the amount of movement of the second lens group in zooming from the wide-angle end to the telephoto end is M2.
0.00 <M1 / M2 <1.00
This to satisfy the conditional expression, features and be Luz Murenzu. The first lens group of negative power, the second lens group of positive power, the first part group of positive power, and the second part group of negative power arranged in order from the object side to the image side. It has a third subset of positive power, and the distance between the first lens group and the second lens group is shorter at the telephoto end than at the wide-angle end, and the distance between adjacent lens groups changes during zooming. In the zoom lens
When focusing from infinity to the closest distance, the first subgroup moves to the object side, and the second subgroup moves to the image side.
The second lens group is composed of a positive lens, a positive lens, and a negative lens arranged in order from the object side to the image side .
When the amount of movement of the first lens group in zooming from the wide-angle end to the telephoto end is M1, and the amount of movement of the second lens group in zooming from the wide-angle end to the telephoto end is M2.
0.00 <M1 / M2 <1.00
This to satisfy the conditional expression, features and be Luz Murenzu. According to any one of claims 1 to 18 , wherein the second lens group, the first subgroup, and the second subgroup move toward the object when zooming from the wide-angle end to the telephoto end. Described zoom lens. The first lens group of negative power, the second lens group of positive power, the first part group of positive power, and the second part group of negative power arranged in order from the object side to the image side. It has a third subset of positive power, and the distance between the first lens group and the second lens group is shorter at the telephoto end than at the wide-angle end, and the distance between adjacent lens groups changes during zooming. In the zoom lens
When focusing from infinity to the closest distance, the first subgroup moves to the object side, and the second subgroup moves to the image side.
When zooming from the wide-angle end to the telephoto end, the third subgroup moves to the image side .
When the amount of movement of the first lens group in zooming from the wide-angle end to the telephoto end is M1, and the amount of movement of the second lens group in zooming from the wide-angle end to the telephoto end is M2.
0.00 <M1 / M2 <1.00
Satisfies the following conditional expressions and to Luz Murenzu. A zoom lens according to any one of claims 1 to 2 0, an imaging apparatus characterized by comprising an imaging element for receiving an image formed by the zoom lens.