JP7218208B2 - ZOOM LENS, IMAGING DEVICE AND IMAGING SYSTEM HAVING THE SAME - Google Patents

Description

The present invention relates to a zoom lens and an imaging apparatus having the zoom lens, and is particularly suitable as an imaging optical system for use in imaging apparatuses such as digital still cameras, video cameras, surveillance cameras, broadcast cameras, and the like.

A zoom lens used in an imaging apparatus is required to have good optical performance over the entire zoom range while being compact and having a high zoom ratio. As a zoom lens that satisfies such requirements, a positive lead type zoom lens having a first lens group with a positive refractive power closest to the object side is known.

Patent Document 1 discloses a zoom lens composed of first to sixth lens groups having positive, negative, positive, positive, positive, and positive refractive powers arranged in order from the object side to the image side.

Patent Document 2 discloses a zoom lens composed of first to seventh lens groups having refractive powers of positive, negative, positive, positive, negative, negative, and positive arranged in order from the object side to the image side. there is

JP 2014-142451 A JP 2015-212725 A

2. Description of the Related Art In recent years, as imaging devices, for example, devices such as surveillance cameras that have a pan-tilt mechanism and devices that use image recognition technology such as person identification have been adopted. In such an image pickup apparatus, further improvement in performance is required while maintaining the downsizing of the optical system and the increase in the zoom ratio.

In a positive lead type zoom lens, in order to achieve higher optical performance over the entire zoom range while miniaturizing the zoom lens and increasing the zoom ratio, the number of lens groups that make up the zoom lens and the number of lenses in each lens group It is important to set the configuration appropriately.

SUMMARY OF THE INVENTION It is an object of the present invention to provide a zoom lens that is compact and has a high zoom ratio and yet is capable of obtaining good optical characteristics over the entire zoom range, and an imaging apparatus and an imaging system having the zoom lens.

The zoom lens of the present invention has a rear group including a first lens group with positive refractive power, a second lens group with negative refractive power, and four or more lens groups arranged in order from the object side to the image side. A zoom lens that
having an aperture stop,
During zooming, the first lens group is stationary, and two or more lens groups arranged closer to the image side than the aperture stop move to change the distance between adjacent lens groups ,
The first lens group has five or more lenses including a plurality of positive lenses ,
DL1 is the distance on the optical axis from the most object-side lens surface to the most image-side lens surface of the first lens group, fw is the focal length of the zoom lens at the wide-angle end, and the focal point of the zoom lens at the telephoto end When the distance is ft and the minimum Abbe number of the material of the plurality of positive lenses is νd1min ,
0.05<DL1/ft<0.40
25.0<ft/fw<200.0
55<νd1min
It is characterized by satisfying the following conditional expression:

According to the present invention, it is possible to obtain a compact zoom lens that can easily obtain good optical characteristics over the entire zoom range at a high zoom ratio.

Lens sectional view of Example 1 Various aberration diagrams of Example 1 Lens sectional view of Example 2 Various aberration diagrams of Example 2 Lens sectional view of Example 3 Various aberration diagrams of Example 3 Lens sectional view of Example 4 Various aberration diagrams of Example 4 Lens sectional view of Example 5 Various aberration diagrams of Example 5 Lens sectional view of Example 6 Example 6 Aberration chart Lens sectional view of Example 7 Various aberration diagrams of Example 7 Lens sectional view of Example 8 Various aberration diagrams of Example 8 Lens section of Example 9 Various aberration diagrams of Example 9 Embodiment of the Imaging Device of the Present Invention

The zoom lens of the present invention has high optical performance over the entire zoom range while being compact and having a high zoom ratio.

A zoom lens of the present invention includes a first lens group with positive refractive power, a second lens group with negative refractive power, and a rear group including four or more lens groups arranged in order from the object side to the image side. and the first lens group does not move during zooming. The distance between adjacent lens groups changes during zooming. A zoom lens has an aperture stop and two or more lens groups on the image side of the aperture stop that move during zooming. The first lens group has five or more lenses and does not move during zooming.

FIG. 1 is a cross-sectional view of the zoom lens at the wide-angle end (short focal length end) of Example 1 of the present invention. 2A, 2B, and 2C are aberration diagrams at the wide-angle end, intermediate zoom position, and telephoto end (long focal length end) of the zoom lens of Example 1, respectively. Example 1 is a zoom lens with a zoom ratio of 38.50 and an F number of 1.60 to 5.20.

FIG. 3 is a lens sectional view at the wide-angle end of the zoom lens of Example 2 of the present invention. 4A, 4B, and 4C are aberration diagrams of the zoom lens of Example 2 at the wide-angle end, intermediate zoom position, and telephoto end, respectively. Example 2 is a zoom lens with a zoom ratio of 39.10 and an F number of 1.65 to 4.94.

FIG. 5 is a lens sectional view at the wide-angle end of the zoom lens of Example 3 of the present invention. 6A, 6B, and 6C are aberration diagrams of the zoom lens of Example 3 at the wide-angle end, intermediate zoom position, and telephoto end, respectively. Example 3 is a zoom lens with a zoom ratio of 45.00 and an F number of 1.60 to 5.20.

FIG. 7 is a lens sectional view at the wide-angle end of the zoom lens of Example 4 of the present invention. 8A, 8B, and 8C are aberration diagrams of the zoom lens of Example 4 at the wide-angle end, intermediate zoom position, and telephoto end, respectively. Example 4 is a zoom lens with a zoom ratio of 38.50 and an F number of 1.60 to 5.20.

FIG. 9 is a lens sectional view at the wide-angle end of the zoom lens of Example 5 of the present invention. 10A, 10B, and 10C are aberration diagrams of the zoom lens of Example 5 at the wide-angle end, intermediate zoom position, and telephoto end, respectively. Example 5 is a zoom lens with a zoom ratio of 42.00 and an F number of 1.60 to 5.20.

FIG. 11 is a lens cross-sectional view at the wide-angle end of the zoom lens according to Example 6 of the present invention. 12A, 12B, and 12C are aberration diagrams of the zoom lens of Example 6 at the wide-angle end, intermediate zoom position, and telephoto end, respectively. Example 6 is a zoom lens with a zoom ratio of 38.50 and an F number of 1.60 to 5.20.

FIG. 13 is a lens sectional view at the wide-angle end of the zoom lens of Example 7 of the present invention. 14A, 14B, and 14C are aberration diagrams of the zoom lens of Example 7 at the wide-angle end, intermediate zoom position, and telephoto end, respectively. Example 7 is a zoom lens with a zoom ratio of 70.00 and an F number of 2.00 to 8.00.

FIG. 15 is a lens sectional view at the wide-angle end of the zoom lens of Example 8 of the present invention. 16A, 16B, and 16C are aberration diagrams of the zoom lens of Example 8 at the wide-angle end, intermediate zoom position, and telephoto end, respectively. Example 8 is a zoom lens with a zoom ratio of 39.10 and an F number of 1.65 to 4.94.

FIG. 17 is a cross-sectional view of the zoom lens at the wide-angle end of Example 9 of the present invention. 18A, 18B, and 18C are aberration diagrams of the zoom lens of Example 9 at the wide-angle end, intermediate zoom position, and telephoto end, respectively. Example 9 is a zoom lens with a zoom ratio of 38.50 and an F number of 1.60 to 5.20.

19A and 19B are schematic diagrams of essential parts of the image pickup apparatus of the present invention.

The zoom lens of each embodiment is an imaging optical system used in imaging devices such as video cameras, digital cameras, TV cameras, surveillance cameras, and the like. In the sectional view of the lens, the left side is the subject side (object side) (front), and the right side is the image side (rear side). In the lens sectional view, L0 is a zoom lens. i indicates the order of the lens groups from the object side, and Li is the i-th lens group. LR is a rear group including a plurality of lens groups.

In the lens sectional view, SP is an aperture stop, which is arranged on the image side of the second lens unit L2. In the cross-sectional view of the lens, P is an optical element corresponding to an optical filter, face plate, crystal low-pass filter, infrared cut filter, and the like. I is an image plane, on which an imaging element (photoelectric conversion element) such as a CCD sensor or a CMOS sensor is placed when used as an imaging optical system of a video camera or a digital still camera.

Arrows indicate the locus of movement of each lens group during zooming (magnification change) from the wide-angle end to the telephoto end. The focus arrow indicates the direction of movement of the lens group during focusing from infinity to close.

In the spherical aberration diagrams, Fno is the F-number. In addition, the solid line is the d-line (wavelength 587.56 nm), the double-dotted line is the g-line (wavelength 435.84 nm), the dashed-dotted line is the C-line (wavelength 656.27 nm), and the rough dotted line is the F-line (wavelength 486.13 nm). showing. In the astigmatism diagrams, the solid line is the sagittal image plane on the d-line, and the dotted line is the meridional image plane. Distortion is shown for the d-line. The diagram of chromatic aberration of magnification shows aberrations of g-line, C-line, and F-line with respect to d-line. ω is the imaging half angle of view.

In the lens cross-sectional views of Examples 1, 3 to 7, and 9, L1 is the first lens group with positive refractive power, L2 is the second lens group with negative refractive power, and LR is the rear group. The rear group LR includes a third lens group L3 with positive refractive power, a fourth lens group L4 with negative refractive power, a fifth lens group L5 with positive refractive power, a sixth lens group L6 with negative refractive power, and a positive refractive power. It consists of a seventh lens group with refractive power. Examples 1, 3 to 7, and 9 are seven-group zoom lenses. The first lens unit L1 and the seventh lens unit L7 are stationary during zooming.

The fifth lens unit L5 is moved to correct image plane fluctuations accompanying zooming, and focusing is performed. A solid-line curve 5a and a dotted-line curve 5b regarding the fifth lens unit L5 are movement trajectories for correcting image plane fluctuations accompanying zooming when focusing on infinity and short distance, respectively. Focusing from infinity to a short distance is performed by extending the fifth lens unit L5 forward (toward the object side) as indicated by an arrow 5c.

In the lens cross-sectional views of Examples 2 and 8, L1 is the first lens group with positive refractive power, L2 is the second lens group with negative refractive power, and LR is the rear group. The rear group LR comprises a third lens group L3 with positive refractive power, a fourth lens group L4 with positive refractive power, a fifth lens group L5 with negative refractive power, and a sixth lens group L6 with positive refractive power. be. Examples 2 and 8 are six-group zoom lenses. In Examples 2 and 8, the first lens unit L1 and the sixth lens unit L6 do not move during zooming.

In Examples 2 and 8, the fifth lens unit L5 is moved to correct the image plane fluctuation accompanying zooming, and focusing is performed.

A solid-line curve 5a and a dotted-line curve 5b regarding the fifth lens unit L5 are movement trajectories for correcting image plane fluctuations accompanying zooming when focusing on infinity and short distance, respectively. Focusing from infinity to short distance is performed by retracting the fifth lens unit L5 backward as indicated by an arrow 5C.

Each embodiment has a first lens group with positive refractive power, a second lens group with negative refractive power, and a rear group including four or more lens groups, which are arranged in order from the object side to the image side. However, the distance between adjacent lens groups changes during zooming. The first lens group L1 has five or more lenses, and two or more lens groups that move toward the image side of the aperture stop SP during zooming. The first lens unit L1 does not move during zooming, so that the zoom lenses of the respective embodiments are small in size and have a high zoom ratio, while also satisfactorily correcting various aberrations.

In addition, five or more lenses are arranged in the first lens unit L1 where the height of incidence of axial marginal rays is high at the telephoto end, thereby softening the curvature of each lens surface. It also reduces the occurrence of spherical aberration and coma on the telephoto side. At least one set of the five or more lenses here may be cemented together. That is, even when n lenses are cemented together to form one cemented lens, the number of lenses is n.

Also, in order to satisfactorily correct aberration fluctuations during zooming, two or more lens groups are provided that move toward the image side of the aperture stop SP during zooming. Generally, in an imaging optical system, off-axis rays cross the optical axis at the position of the aperture stop, so the direction of separation from the optical axis is reversed before and after the aperture stop. Therefore, by moving a plurality of lens groups on the image side of the aperture stop SP during zooming, it becomes easy to satisfactorily correct spherical aberration and curvature of field, especially on the wide-angle side.

In addition, by keeping the first lens unit L1, which has the largest outer diameter, stationary during zooming, a compact imaging apparatus is obtained while preventing an increase in size of the drive system.

In each embodiment, DL1 is the distance (optical total length) on the optical axis from the lens surface closest to the object side to the lens surface closest to the image side in the first lens unit L1. Let fw be the focal length of the zoom lens L0 at the wide-angle end, and ft be the focal length of the zoom lens L0 at the telephoto end. At this time,
0.05<DL1/ft<0.40 (1)
25.0<ft/fw<200.0 (2)
satisfies the following conditional expression.

By satisfying the conditional expressions (1) and (2), it is possible to achieve a compact zoom lens and a high zoom ratio, while achieving high optical performance over the entire zoom range.

Next, the technical meanings of the above conditional expressions (1) and (2) will be explained.

Conditional expression (1) defines the ratio of the distance (optical total length) on the optical axis from the lens surface closest to the object side to the lens surface closest to the image side in the first lens unit L1 and the focal length at the telephoto end. ing. By satisfying the conditional expression (1), the zoom lens can be downsized and spherical aberration, coma aberration, etc. can be satisfactorily corrected on the telephoto side, and the downsizing of the zoom lens and good optical performance can be obtained.

If the upper limit of conditional expression (1) is exceeded, the ratio between the total optical length and the focal length at the telephoto end becomes too large, and light rays forming an image at the peripheral image height on the wide-angle side extend beyond the optical axis in the first lens unit L1. will pass through a position far from That is, the effective diameter of the first lens unit L1 increases, making it difficult to achieve a compact zoom lens. Further, if the lower limit of conditional expression (1) is exceeded, the focal length at the telephoto end becomes long, and the zoom lens becomes large in order to correct various aberrations, which is not preferable.

Conditional expression (2) defines the zoom ratio of the zoom lens. By satisfying the conditional expression (2), it is easy to realize a compact zoom lens and a high zoom ratio. If the lower limit of conditional expression (2) is exceeded, the zoom ratio becomes too small, making it difficult to increase the zoom ratio. On the other hand, if the upper limit of conditional expression (2) is exceeded, the refractive power of each lens group becomes excessively strong, which increases various aberrations such as spherical aberration and coma, which is not preferable.

In each embodiment, preferably, the numerical ranges of conditional expressions (1) and (2) are set as follows.

0.06<DL1/ft<0.20 (1a)
30.0<ft/fw<100.0 (2a)
In each embodiment, it is more preferable to set the numerical ranges of conditional expressions (1a) and (2a) as follows.

0.07<DL1/ft<0.15 (1b)
35.0<ft/fw<80.0 (2b)
In each embodiment, it is preferable to satisfy one or more of the following conditional expressions.

Let f1 be the focal length of the first lens group L1, and f2 be the focal length of the second lens group L2. Let BFw be the back focus at the wide-angle end. Let TD be the distance on the optical axis from the lens surface closest to the object side to the image plane (lens total length). The first lens unit L1 has a plurality of positive lenses, and the minimum Abbe number of the material of the positive lenses included in the first lens unit L1 is νd1 _min .

At this time, it is preferable to satisfy one or more of the following conditional expressions.

-10.0<f1/f2<-5.0 (3)
0.3<BFw/fw<3.0 (4)
0.3<TD/ft<1.4 (5)
-5.0<f2/fw<-1.0 (6)
0.1<f1/ft<1.0 (7)
55<νd1 _min (8)
Next, the technical meaning of the above conditional expressions will be explained.

Conditional expression (3) defines the ratio between the focal length of the first lens unit L1 and the focal length of the second lens unit L2. Exceeding the upper limit of conditional expression (3) is not preferable because the positive refractive power of the first lens unit L1 becomes excessively strong, which increases various aberrations such as spherical aberration and coma, especially on the telephoto side. . In addition, the refractive power of the second lens unit L2 is excessively weakened (the absolute value of the negative refractive power becomes small), and the amount of movement of the second lens unit L2 increases during zooming for high zooming. This is not preferable because it increases the size of the lens.

If the lower limit of conditional expression (3) is exceeded, the negative refractive power of the second lens unit L2 becomes excessively strong (the absolute value of the negative refractive power increases). This is not preferable because the variation of coma aberration becomes large.

Conditional expression (4) defines the ratio of the focal length of the zoom lens at the back focus and the wide-angle end. Here, the back focus is the distance from the final surface of the lens to the paraxial image plane expressed in air conversion length.

Exceeding the upper limit of conditional expression (4) is not preferable because the back focus becomes too long and the size of the zoom lens increases. If the lower limit of conditional expression (4) is exceeded, the back focus becomes too short, and the space for mounting optical elements such as a low-pass filter and an infrared cut filter becomes insufficient, which is not preferable.

Conditional expression (5) defines the ratio of the total length of the lens to the focal length of the zoom lens at the telephoto end. Exceeding the upper limit of conditional expression (5) is not preferable because the total length of the lens becomes too long and the size of the zoom lens increases. If the lower limit of conditional expression (5) is exceeded, the total length of the lens becomes excessively short, and the refractive power of each lens group becomes excessively strong, thereby increasing various aberrations such as spherical aberration and coma.

Conditional expression (6) defines the ratio of the focal length of the second lens unit L2 to the focal length of the zoom lens at the wide-angle end. If the lower limit of conditional expression (6) is exceeded, the negative refracting power of the second lens unit L2 becomes weak, and it is necessary to excessively increase the amount of movement of the second lens unit L2 in order to achieve a high zoom ratio. , the zoom lens becomes large, which is not preferable. If the negative refractive power of the second lens unit L2 increases beyond the upper limit of conditional expression (6), fluctuations in curvature of field and coma increase during zooming, which is undesirable.

Conditional expression (7) defines the ratio between the focal length of the first lens unit L1 and the focal length of the zoom lens at the telephoto end. If the upper limit of conditional expression (7) is exceeded, the positive refractive power of the first lens unit L1 becomes weak, and it is necessary to increase the amount of movement of the lens units during zooming in order to achieve a high zoom ratio. The zoom lens becomes large, which is not preferable. If the lower limit of conditional expression (7) is exceeded, the positive refracting power of the first lens unit L1 becomes strong and spherical aberration increases at the telephoto end, which is not preferable.

Conditional expression (8) defines the Abbe number or the minimum Abbe number among the materials of the positive lens included in the first lens unit L1. By satisfying conditional expression (8), it becomes easy to suppress chromatic aberration on the telephoto side. In recent years, the number of surveillance cameras that use near-infrared illumination as nighttime illumination has increased, and there is a demand for correction of chromatic aberration in the visible region to the near-infrared region. By correcting chromatic aberration in the visible region to the near-infrared region, a zoom lens suitable for monitoring not only during the daytime but also at nighttime can be easily obtained.

If the lower limit of conditional expression (8) is exceeded, the dispersion of the material of the positive lens becomes highly dispersed, and longitudinal chromatic aberration and lateral chromatic aberration increase on the telephoto side, which is not preferable. In addition, when trying to correct chromatic aberration, it is necessary to increase the refractive power of each lens, which is not preferable because spherical aberration and coma aberration increase on the telephoto side.

In each embodiment, preferably, the numerical ranges of conditional expressions (3) to (8) are set as follows.

-9.0<f1/f2<-5.5 (3a)
0.6<BF/fw<2.0 (4a)
0.4<TD/ft<1.2 (5a)
−4.0<f2/fw<−1.4 (6a)
0.15<f1/ft<0.7 (7a)
67<νd1 _min (8a)
In each embodiment, it is more preferable to set the numerical ranges of conditional expressions (3a) to (8a) as follows.

-8.0<f1/f2<-6.0 (3b)
0.9<BF/fw<1.5 (4b)
0.5<TD/ft<1.0 (5b)
-3.0<f2/fw<-1.8 (6b)
0.2<f1/ft<0.5 (7b)
79<νd1 _min (8b)
Focusing in each embodiment is preferably performed by moving at least one lens group in the rear group LR along the optical axis. In each embodiment, focusing may be performed by moving not one lens group but a plurality of lens groups along the optical axis.

In each embodiment, it is preferable that the number of positive lenses included in the first lens group L1 is three or more. As a result, the curvature of the positive lens, which has a strong positive refractive power (power) in the first lens unit L1 having a positive focal length, is relaxed to reduce spherical aberration and coma, especially on the telephoto side. making it easier.

It is preferable to arrange the aperture stop SP closer to the image side than the second lens unit L2. By locating the second lens unit closer to the image side than the second lens unit L2, which has a strong negative refractive power because it serves as the main zoom lens unit, it is possible to reduce the size and weight of the zoom lens by suppressing an increase in the effective diameter of the rear group LR. making it easy to achieve.

In each embodiment, the aperture diameter of the aperture diaphragm SP may be fixed or varied during zooming. By changing the diameter of the aperture stop SP, it is possible to cut underline coma flare caused by off-axis luminous flux, which is greatly generated at the telephoto end, and obtain better optical performance.

In each embodiment, by configuring each element as described above, the zoom lens can be downsized and the zoom can be increased, and high optical performance can be obtained over the entire zoom range.

Also, by arbitrarily combining a plurality of the above conditional expressions, the effect of the present invention can be further enhanced.

Next, the lens construction of the lens group of each embodiment will be described. Unless otherwise specified, each lens is arranged in order from the object side to the image side.
[Example 1]
The first lens unit L1 is composed of a cemented lens in which a negative lens and a positive lens are cemented together, a cemented lens in which a positive lens and a negative lens are cemented together, and a positive lens, and does not move during zooming. By having five lenses, spherical aberration and coma are well corrected especially on the telephoto side. Also, by having a cemented lens, longitudinal chromatic aberration is corrected well, especially at the telephoto end.

The second lens unit L2 is composed of a negative lens, a cemented lens in which a negative lens and a positive lens are cemented together, and a negative lens, and moves during zooming.

The third lens group L3 is composed of a positive lens and does not move during zooming.

The fourth lens group L4 is composed of a negative lens and moves during zooming.

The fifth lens unit L5 is composed of a cemented lens in which a positive lens and a negative lens are cemented together, and moves during zooming to serve as a compensator and focus. Having one cemented lens suppresses fluctuations in chromatic aberration of magnification during focusing, and also facilitates control during focusing due to weight reduction.

The sixth lens group L6 is composed of a negative lens and moves during zooming.

The seventh lens group L7 is composed of a positive lens, and does not move during zooming.

By making the final lens group a lens group with a positive refractive power, telecentricity is enhanced, and off-axis light beams enter the image sensor at an angle close to vertical, suppressing light falloff around the screen due to shading. ing.

An aperture stop SP is provided between the second lens group L2 and the third lens group L3 and does not move during zooming.
[Example 2]
The lens configuration of the first lens unit L1 is the same as that of the first embodiment.

The second lens unit L2 is composed of three negative lenses and a positive lens, and moves during zooming.

The third lens unit L3 is composed of two positive lenses, a cemented lens in which a negative lens and a positive lens are cemented together, and moves during zooming.

The fourth lens unit L4 is composed of a cemented lens in which a positive lens and a negative lens are cemented together, and moves during zooming.

The fifth lens unit L5 is composed of a cemented lens in which a positive lens and a negative lens are cemented together, and moves during zooming to serve as a compensator and a focus.

The sixth lens unit L6 is composed of a cemented lens in which a positive lens and a negative lens are cemented together, and does not move during zooming.

An aperture stop SP is provided between the second lens group L2 and the third lens group L3 and does not move during zooming.
[Example 3]
The first lens unit L1 is composed of a cemented lens in which a negative lens and a positive lens are cemented together, and three positive lenses, and does not move during zooming.

The lens configuration of the second lens unit L2 is the same as that of the first embodiment.

The third lens unit L3 is composed of a positive lens, has an aperture diaphragm SP on the object side, and moves together with the aperture diaphragm SP (in the same locus) during zooming.

The lens configurations of the fourth lens group L4, the fifth lens group L5, the sixth lens group L6, and the seventh lens group L7 are the same as those of the first embodiment.
[Example 4]
The first lens unit L1 is composed of a cemented lens in which a negative lens and a positive lens are cemented together, a cemented lens in which a negative lens and a positive lens are cemented together, and a positive lens, and does not move during zooming.

The lens configurations of the second lens group L2, the third lens group L3, the fourth lens group L4, the fifth lens group L5, the sixth lens group L6, and the seventh lens group L7 are the same as those of the first embodiment.

An aperture stop SP is provided between the second lens group L2 and the third lens group L3 and does not move during zooming.
[Example 5]
The first lens unit L1 is composed of a cemented lens in which a negative lens and a positive lens are cemented together, a cemented lens in which a positive lens and a negative lens are cemented together, and two positive lenses, and does not move during zooming.

The lens configurations of the second lens group L2, the third lens group L3, the fourth lens group L4, the fifth lens group L5, the sixth lens group L6, and the seventh lens group L7 are the same as those of the first embodiment.

An aperture stop SP is provided between the second lens group L2 and the third lens group L3 and does not move during zooming.
[Example 6]
The lens configuration of the first lens unit L1 is the same as that of the third embodiment.

The lens configurations of the second lens group L2, the third lens group L3, the fourth lens group L4, the fifth lens group L5, the sixth lens group L6, and the seventh lens group L7 are the same as those of the first embodiment.

An aperture stop SP is provided between the second lens group L2 and the third lens group L3 and does not move during zooming.
[Example 7]
The lens configurations of the first lens group L1, the second lens group L2, the third lens group L3, the fourth lens group L4, the fifth lens group L5, the sixth lens group L6, and the seventh lens group L7 are the same as those in the first embodiment. It is the same.

An aperture stop SP is provided between the second lens group L2 and the third lens group L3 and does not move during zooming.
[Example 8]
The lens configuration of the first lens unit L1 is the same as that of the first embodiment.

The lens configuration of the second lens unit L2 is the same as that of the second embodiment.

The third lens unit L3 is composed of a cemented lens in which a positive lens and a negative lens are cemented together, and does not move during zooming.

The fourth lens unit L4 is composed of two positive lenses, a cemented lens in which a negative lens and a positive lens are cemented together, and a cemented lens in which a positive lens and a negative lens are cemented together, and moves during zooming.

The lens configurations of the fifth lens group L5 and the sixth lens group L6 are the same as those of the second embodiment.

An aperture stop SP is provided between the third lens group L3 and the fourth lens group L4 and does not move during zooming.
[Example 9]
The lens configurations of the first lens group L1 to the seventh lens group L7 are the same as those of the first embodiment.

An aperture stop SP is provided between the second lens group L2 and the third lens group L3 and does not move during zooming.

Next, an embodiment of an imaging apparatus using the zoom lens of the present invention as an imaging optical system will be described with reference to FIG.

In FIG. 19A, 10 is a surveillance camera body, and 11 is an imaging optical system configured by any one of the zoom lenses described in the first to ninth embodiments. Reference numeral 12 denotes an imaging element (photoelectric conversion element) such as a CCD sensor or a CMOS sensor, which is built in the camera body and receives an object image formed by the imaging optical system 11 . A memory 13 records information corresponding to the subject image photoelectrically converted by the image sensor 12 . Reference numeral 14 denotes a network cable for transferring the subject image photoelectrically converted by the image sensor 12 .

FIG. 19(B) shows an example in which a dome-shaped cover 15 is inserted into the camera body 10 and the camera is attached to the ceiling. The imaging device is not limited to a surveillance camera, and can also be used in a video camera, a digital camera, and the like.

The image pickup apparatus of the present invention may have a circuit for electrically correcting either one or both of the distortion aberration and the chromatic aberration of magnification together with any one of the zoom lenses described above.

If the zoom lens is configured to allow for distortion aberration and the like in this manner, the number of lenses in the entire zoom lens can be reduced, facilitating miniaturization. Further, by electrically correcting the chromatic aberration of magnification, it becomes easy to reduce color bleeding in the photographed image and improve the resolving power.

Although preferred embodiments of the present invention have been described above, the present invention is not limited to these embodiments, and various modifications and changes are possible within the scope of the gist.

For example, an imaging system (monitoring system) including the zoom lens of each embodiment and a control section for controlling the zoom lens may be configured. In this case, the controller can control the zoom lens so that each lens group moves as described above during zooming, focusing, and image blur correction. At this time, the controller does not need to be configured integrally with the zoom lens, and the controller may be configured separately from the zoom lens.

For example, a configuration in which a control unit (control device) disposed far from a driving unit that drives each lens of a zoom lens includes a transmission unit that transmits a control signal (command) for controlling the zoom lens is adopted. may According to such a controller, the zoom lens can be remotely controlled. Further, by providing an operation unit such as a controller and buttons for remotely operating the zoom lens in the control unit, the zoom lens may be controlled according to the user's input to the operation unit.

For example, an enlargement button and a reduction button are provided as an operation unit, and when the user presses the enlargement button, the magnification of the zoom lens increases, and when the user presses the reduction button, the magnification of the zoom lens decreases. For example, it may be configured such that a signal is sent from the control section to the driving section of the zoom lens. The imaging system may also have a display unit such as a liquid crystal panel that displays information (moving state) regarding zooming of the zoom lens. The information about the zoom of the zoom lens is, for example, the zoom magnification (zoom state) and the movement amount (movement state) of each lens group. In this case, the user can remotely operate the zoom lens via the operation unit while viewing information about the zoom of the zoom lens displayed on the display unit. At this time, the display unit and the operation unit may be integrated by adopting a touch panel or the like.

Numerical Examples 1 to 9 corresponding to Examples 1 to 9 of the present invention are shown below. In each numerical example, i indicates the order of the optical surfaces from the object side. ri is the radius of curvature of the i-th optical surface (i-th surface), di is the distance between the i-th surface and the i+1-th surface, and ndi and νdi are the refraction of the material of the i-th optical member with respect to the d-line. ratio and Abbe number. BF (back focus) is the distance from the final surface of the lens excluding the filter to the paraxial image plane expressed in terms of air length. * means aspheric surface.

Here, the Abbe numbers of the optical materials used in each claim and each example of the present invention are as follows.

Let nF, nd, and nC be the refractive indices for the F-line (486.1 nm), d-line (587.6 nm), and C-line (656.3 nm) of Fraunhofer lines, respectively. The Abbe number νd is given by the following formula.

νd = (nd-1)/(nF-nC)
Further, when k is the eccentricity, A4, A6, A8, A10, and A12 are the aspherical coefficients, and x is the displacement in the optical axis direction at the position of the height h from the surface vertex, the aspherical shape is teeth,
x=(h ² /R)/[1+{1−(1+k)(h/R) ² } ^1/2 ]+A4h ⁴ +A6h ⁶ +A8h ⁸ +A10h ¹⁰ +A12h ¹²
is represented by where R is the paraxial radius of curvature.

Further, the locus of movement of the n-th lens group in each example is represented by the following formula, and the lens arrangement in the middle of the zoom described above is described as intermediate in Numerical Examples 1 to 9.

Note that m2 in the formula is a value obtained by normalizing the amount of movement of the second lens group, which is the main variable magnification group, from the wide-angle end by the amount of movement from the wide-angle end to the telephoto end. 1 at the end. mn is the amount of movement of the n-th lens group from the wide-angle end. Bnk is the k-th order movement amount coefficient of the n-th lens.

mn=Σ(Bnk× ^mnk )
=Bn1·m2+Bn2·m2 ² +Bn3·m2 ³ +Bn4·m2 ⁴
+Bn5·m2 ⁵ +Bn6·m2 ⁶ +Bn7·m2 ⁷ +Bn8·m2 ⁸
+Bn9・m2 ⁹ +Bn10・m2 ¹⁰
Table 1 shows the correspondence with the above-described conditional expressions in each numerical example.

(Numerical example 1)
unit mm

Surface data surface number rd nd vd
1 135.440 1.50 1.80400 46.5
2 41.572 5.34 1.49700 81.5
3 -417.011 0.15
4 162.239 4.07 1.49700 81.5
5 -62.757 1.25 1.69680 55.5
6 -219.940 0.15
7 42.032 4.81 1.49700 81.5
8 -363.361 (variable)
9 -90.232 0.60 2.00100 29.1
10 12.377 4.86
11 -15.200 0.50 1.91082 35.3
12 -49.301 3.59 1.95906 17.5
13 -13.312 0.15
14* -27.315 0.50 1.85135 40.1
15 -270.531 (variable)
16 (Aperture) ∞ 0.50
17* 15.648 5.21 1.61881 63.9
18* -94.254 (variable)
19 28.417 0.70 2.00100 29.1
20 13.447 (variable)
21* 12.154 4.51 1.49710 81.6
22 -14.442 0.70 2.00100 29.1
23 -19.358 (variable)
24 58.558 0.50 1.82080 42.7
25* 11.571 (variable)
26 -19.935 1.55 1.53110 55.9
27* -6.240 0.67
28 ∞ 0.80 1.51633 64.1
29 ∞ 3.28
Image plane ∞

14th surface of aspheric data
K = 1.43437e+000 A 4= 6.66427e-006 A 6= 3.35319e-007 A 8=-9.44873e-009 A10= 8.56172e-011

17th side
K = 8.84661e-001 A 4=-5.67657e-005 A 6=-7.26367e-007 A 8= 5.45842e-009 A10=-4.29017e-011 A12=-7.80384e-014

18th side
K = 5.52561e+001 A 4= 6.98422e-006 A 6=-7.55519e-007 A 8= 1.77602e-008 A10=-1.83767e-010 A12= 7.21553e-013

21st side
K =-7.18856e-001 A 4=-4.15424e-005 A 6=-3.13278e-007 A 8= 1.15458e-008 A10=-2.82199e-010 A12= 2.71965e-012

25th side
K = 1.00003e+000 A 4= 4.32466e-006 A 6= 1.01322e-006 A 8=-5.85839e-007 A10= 4.77749e-008 A12=-1.45650e-009

27th side
K = 0.00000e+000 A 4= 1.47511e-003 A 6=-1.68990e-005 A 8= 6.09181e-007

Various data Zoom ratio 38.50
Wide Angle Medium Telephoto Focal Length 4.50 52.35 173.30
F number 1.60 3.80 5.20
Half angle of view (degrees) 36.2 3.79 1.07
Image height 3.20 3.20 3.20
Overall lens length 129.57 129.57 129.57
BF 4.47 4.47 4.47

d8 0.70 38.34 47.75
d15 53.01 15.37 5.96
d18 3.56 6.38 10.91
d20 15.70 2.04 7.96
d23 8.64 10.09 1.00
d25 2.08 11.46 10.09

Lens group data group Starting surface Focal length
1 1 63.07
2 9 -9.97
3 16 22.09
4 19 -26.11
5 21 18.03
6 24 -17.65
7 26 16.45

Zoom trajectory data
B41=15.3828 B42=-62.9295 B43=144.1545
B44=-153.1555 B45=45.2281 B46=18.6793

B61=-38.7593 B62=73.0649 B63=-103.8985 B64=56.1375 B65=14.3168
B66=-56.4231 B67=132.8078 B68=11.6954 B69=-157.7514 B610=60.7977


(Numerical example 2)
unit mm

Surface data surface number rd nd vd
1 87.044 1.55 1.80400 46.5
2 36.672 6.92 1.49700 81.5
3 817.941 0.20
4 97.926 5.45 1.49700 81.5
5 -77.724 1.33 1.69680 55.5
6 ∞ 0.10
7 39.606 5.56 1.49700 81.5
8 -505.418 (variable)
9 72.999 0.71 1.83481 42.7
10 8.504 3.40
11 404.480 0.53 1.77250 49.6
12 13.778 3.15
13 -15.499 0.51 1.69680 55.5
14 -276.818 0.10
15 31.737 2.88 1.85478 24.8
16 -26.275 (variable)
17 ∞ 0.00
18 (aperture) ∞ (variable)
19 14.441 5.14 1.49700 81.5
20 105.509 3.11
21* 15.764 4.50 1.58313 59.4
22* -86.935 0.55
23 -47.897 0.60 1.74951 35.3
24 11.108 3.93 1.49700 81.5
25 -44.961 (variable)
26 20.488 3.16 1.49700 81.5
27 -12.610 0.50 1.69680 55.5
28 -38.098 (variable)
29 -140.306 1.57 1.95906 17.5
30 -16.787 0.50 1.83481 42.7
31 8.404 (variable)
32 13.235 4.17 1.60311 60.6
33 -7.665 0.50 1.84666 23.8
34 -12.653 1.50
35 ∞ 0.80 1.51500 70.0
36 ∞ 3.38
Image plane ∞

Aspheric surface data 21st surface
K = 5.81215e-001 A 4=-2.56847e-005 A 6=-3.97306e-007 A 8= 4.95147e-009 A10= 2.39812e-011

22nd side
K = 0.00000e+000 A 4= 9.21408e-005 A 6=-9.12258e-007 A 8= 2.78140e-008 A10=-1.28331e-010

Various data Zoom ratio 39.10
Wide Angle Medium Telephoto Focal Length 4.42 47.59 172.64
F number 1.65 3.20 4.94
Half angle of view (degrees) 36.2 3.79 1.07
Image height 3.20 3.20 3.20
Total lens length 129.68 129.68 129.68
BF 5.41 5.41 5.41

d8 0.65 38.37 46.65
d16 47.80 10.08 1.80
d18 8.16 2.56 1.40
d25 0.60 0.33 0.46
d28 1.78 7.35 1.50
d31 4.39 4.70 11.57

Lens group data group Starting surface Focal length
1 1 63.02
2 9 -8.96
3 17 ∞
4 19 21.46
5 26 37.70
6 29 -10.08
7 32 13.12

Zoom trajectory data
B41=-45.2975 B42=127.307 B43=-249.8951 B44=452.9196 B45=-555.4795
B46=261.6228 B47=84.2931 B48=-230.2443 B49=366.7707 B410=-218.7572

B51=-34.0636 B52=111.3409 B53=-280.5657 B54=395.7194 B55=40.7277
B56=-890.5878 B57=1091.8866 B58=-877.2889 B59=856.531 B510=-420.6029


(Numerical example 3)
unit mm

Surface data surface number rd nd vd
1 6378.951 1.50 1.77250 49.6
2 52.010 6.18 1.43875 94.7
3 -251.454 0.15
4 57.987 4.49 1.43875 94.7
5 -888.827 0.15
6 83.270 2.72 1.49700 81.5
7 879.307 0.15
8 68.122 2.26 1.49700 81.5
9 172.003 (variable)
10 -685.683 0.60 2.00100 29.1
11 11.778 5.66
12 -18.554 0.50 1.91082 35.3
13 -67.002 3.58 1.95906 17.5
14 -15.314 0.81
15* -20.293 0.50 1.85135 40.1
16 -48.965 (variable)
17 (Aperture) ∞ 0.50
18* 13.176 6.14 1.61881 63.9
19* -90.285 (variable)
20 21.940 0.70 1.95375 32.3
21 11.069 (variable)
22* 13.142 4.54 1.49710 81.6
23 -13.712 0.70 2.00069 25.5
24 -19.040 (variable)
25 -668.508 0.50 1.82080 42.7
26* 9.993 (variable)
27* -26.950 1.60 1.53110 55.9
28 -6.073 0.67
29 ∞ 0.80 1.51633 64.1
30 ∞ 3.30
Image plane ∞

15th surface of aspheric data
K =-6.00362e+000 A 4=-7.70911e-005 A 6= 4.97190e-007 A 8=-4.46748e-009 A10= 3.91718e-011

18th side
K=-1.80133e-001 A 4=-2.43183e-005 A 6=-1.50341e-007 A 8= 9.50217e-010 A10=-8.10974e-012 A12=-2.93505e-014

19th side
K =-2.11917e+002 A 4=-6.99216e-006 A 6= 1.39784e-007 A 8= 9.41579e-010 A10=-2.95461e-011 A12= 1.23098e-013

22nd side
K =-3.59743e-001 A 4=-2.14802e-005 A 6=-3.25018e-007 A 8= 5.25552e-009 A10=-4.72182e-011 A12= 9.90734e-014

26th side
K = 5.26272e+000 A 4=-5.68854e-004 A 6=-7.09256e-006 A 8=-4.71978e-006 A10= 4.23128e-007 A12=-2.48105e-008

27th side
K = 0.00000e+000A4=-1.38855e-003

Various data Zoom ratio 45.00
Wide Angle Medium Telephoto Focal Length 4.23 50.48 190.19
F number 1.60 3.80 5.20
Half angle of view (degrees) 38.1 3.36 0.89
Image height 3.20 3.20 3.20
Overall lens length 130.00 130.00 130.00
BF 4.49 4.49 4.49

d9 1.06 47.14 58.66
d16 63.12 12.56 1.00
d19 1.54 2.31 4.70
d21 6.16 2.53 14.20
d24 7.70 12.90 1.00
d26 1.73 3.86 1.73

Lens group data group Starting surface Focal length
1 1 72.75
2 10 -10.92
3 17 19.01
4 20 -24.18
5 22 19.33
6 25 -11.99
7 27 14.38

Zoom trajectory data
B31=-4.4405 B32=-1.7135 B33=0.9893
B34=-39.0032 B35=80.1558 B36=-40.4991

B41=3.6799 B42=-27.7952 B43=32.1447
B44=-51.2537 B45=71.8712 B46=-29.9972

B61=-41.045 B62=81.4093 B63=-28.9859
B64=-67.377 B65=97.1261 B66=-41.1278


(Numerical example 4)
unit mm

Surface data surface number rd nd vd
1 153.363 1.50 1.80400 46.5
2 44.040 6.41 1.49700 81.6
3 -265.691 0.15
4 73.203 1.25 1.69680 55.5
5 40.749 3.97 1.49700 81.6
6 295.334 0.15
7 38.446 4.59 1.49700 81.6
8 -3321.585 (variable)
9 -65.589 0.60 2.00100 29.1
10 12.363 4.69
11 -16.717 0.50 1.88100 40.1
12 -40.735 3.32 1.95906 17.5
13 -13.286 0.50
14* -20.668 0.50 1.85135 40.1
15 -105.959 (variable)
16 (Aperture) ∞ 1.00
17* 14.117 5.62 1.61881 63.9
18* -51.205 (variable)
19 33.835 0.70 1.95375 32.3
20 12.399 (variable)
21* 11.764 4.37 1.49710 81.6
22 -13.219 0.70 2.00069 25.5
23 -17.603 (variable)
24 263.909 0.50 1.82080 42.7
25* 13.927 (variable)
26 -14.821 1.36 1.53110 55.9
27* -6.071 0.67
28 ∞ 0.80 1.51633 64.1
29 ∞ 3.29
Image plane ∞

14th surface of aspheric data
K =-1.74427e+000 A 4=-1.74000e-005 A 6= 3.38382e-007 A 8=-1.20814e-008 A10= 1.33727e-010

17th side
K=-1.56879e-001 A 4=-3.16522e-005 A 6=-4.75486e-007 A 8= 1.44912e-009 A10= 2.27402e-011 A12=-4.19535e-013

18th side
K = 6.08604e+000 A 4= 2.02176e-005 A 6=-8.11587e-007 A 8= 1.44777e-008 A10=-1.37555e-010 A12= 3.51563e-013

21st side
K =-5.97589e-001 A 4=-4.80112e-005 A 6=-5.88238e-007 A 8= 2.41253e-008 A10=-6.39426e-010 A12= 6.99695e-012

25th side
K =-3.79812e-001 A 4= 1.37000e-004 A 6=-4.42390e-006 A 8= 3.96804e-007 A10=-2.03834e-008 A12= 2.45593e-010

27th side
K = 0.00000e+000 A 4= 1.45537e-003 A 6=-1.01966e-005 A 8= 4.95915e-007

Various data Zoom ratio 38.50
Wide Angle Medium Telephoto Focal Length 4.43 47.98 170.67
F number 1.60 3.80 5.20
Half angle of view (degrees) 37.5 3.53 0.98
Image height 3.20 3.20 3.20
Overall lens length 120.00 120.00 120.00
BF 4.48 4.48 4.48

d8 0.70 38.14 47.51
d15 48.44 11.00 1.63
d18 2.71 4.07 6.59
d20 11.49 2.61 14.12
d23 7.81 11.97 1.00
d25 1.70 5.06 2.00

Lens group data group Starting surface Focal length
1 1 62.39
2 9 -9.39
3 16 18.49
4 19 -20.85
5 21 17.09
6 24 -17.93
7 26 18.37

Zoom trajectory data
B41=10.1934 B42=-44.6796 B43=120.7353
B44=-154.5859 B45=66.7157 B46=5.5037

B61=-17.6213 B62=-32.1241 B63=78.2779
B64=-45.6835 B65=84.184 B66=-67.3328


(Numerical Example 5)
unit mm

Surface data surface number rd nd vd
1 322.187 1.50 1.77250 49.6
2 42.038 6.90 1.49700 81.5
3 -285.380 0.15
4 230.631 3.53 1.49700 81.5
5 -84.532 1.25 1.69680 55.5
6 -2147.795 0.15
7 98.483 2.31 1.49700 81.5
8 -2669.401 0.15
9 44.643 4.59 1.49700 81.5
10 -400.190 (variable)
11 -172.534 0.60 1.91082 35.3
12 9.900 5.04
13 -16.552 0.50 1.85150 40.8
14 26.171 6.09 1.85478 24.8
15 -13.563 0.15
16* -18.111 0.50 1.85135 40.1
17 -46.536 (variable)
18 (Aperture) ∞ 0.50
19* 15.989 3.74 1.61881 63.9
20* ∞ (variable)
21 37.449 0.70 2.00100 29.1
22 20.418 (variable)
23* 14.314 6.16 1.49710 81.6
24 -11.209 0.70 2.00100 29.1
25 -16.095 (variable)
26 35.354 0.50 1.82080 42.7
27* 11.558 (variable)
28 -15.031 1.69 1.53110 55.9
29* -5.916 0.67
30 ∞ 0.80 1.51633 64.1
31 ∞ 3.30
Image plane ∞

Aspheric data 16th surface
K=-2.21932e-001 A 4= 7.96679e-008 A 6= 5.00899e-007 A 8=-1.00273e-008 A10= 8.58812e-011

19th side
K = 1.09773e+000 A 4=-7.21817e-005 A 6=-4.02238e-007 A 8= 2.27832e-009 A10=-4.56724e-011 A12= 1.21014e-013

20th side
K = 0.00000e+000 A 4=-2.31055e-005 A 6=-1.46406e-007 A 8= 7.40237e-009 A10=-1.04526e-010 A12= 6.31908e-013

23rd side
K =-1.45431e+000 A 4=-1.71568e-005 A 6=-3.97033e-007 A 8= 1.89998e-008 A10=-4.52871e-010 A12= 4.67027e-012

27th side
K = 1.41939e+000 A 4=-5.74407e-005 A 6= 5.63401e-006 A 8=-1.00957e-006 A10= 6.42580e-008 A12=-1.53975e-009

29th side
K = 0.00000e+000 A 4= 1.32196e-003 A 6=-1.37652e-005 A 8= 6.28554e-007

Various data Zoom ratio 42.00
Wide Angle Medium Telephoto Focal Length 4.05 43.72 170.00
F number 1.60 3.80 5.20
Half angle of view (degrees) 40.0 3.95 1.02
Image height 3.20 3.20 3.20
Overall lens length 140.00 140.00 140.00
BF 4.49 4.49 4.49

d10 0.70 40.62 50.60
d17 53.22 13.30 3.32
d20 1.00 6.06 10.71
d22 22.82 6.99 6.81
d25 7.83 8.54 1.00
d27 2.27 12.33 15.41


Lens group data group Starting surface Focal length
1 1 64.14
2 11 -9.89
3 18 25.84
4 21 -45.79
5 23 20.17
6 26 -21.12
7 28 17.26

Zoom trajectory data
B41=35.6457 B42=-84.2873 B43=109.8969
B44=-78.0583 B45=-11.4756 B46=37.9868

B61=-66.5165 B62=95.7769 B63=-92.4075 B64=197.3611 B65=-278.4582
B66=190.4987 B67=22.8005 B68=4.3698 B69=-245.2554 B610=158.6922


(Numerical Example 6)
unit mm

Surface data surface number rd nd vd
1 -422.675 1.50 1.75500 52.3
2 46.929 5.35 1.43875 94.7
3 -157.325 0.15
4 53.183 4.06 1.43875 94.7
5 -556.403 0.15
6 90.475 1.93 1.49700 81.5
7 369.727 0.15
8 66.861 2.63 1.49700 81.5
9 508.390 (variable)
10 -96.644 0.60 2.00100 29.1
11 11.679 4.52
12 -20.579 0.50 1.91082 35.3
13 27.046 6.09 1.96300 24.1
14 -15.183 0.15
15* -27.966 0.50 1.85135 40.1
16 1190.867 (variable)
17 (Aperture) ∞ 1.00
18* 14.931 6.11 1.61881 63.9
19* -67.276 (variable)
20 34.460 0.70 1.95375 32.3
21 13.285 (variable)
22* 11.503 5.04 1.49710 81.6
23 -11.211 0.70 2.00069 25.5
24 -15.252 (variable)
25 -951.385 0.50 1.82080 42.7
26* 11.460 (variable)
27* -16.077 1.50 1.53110 55.9
28 -6.528 0.66
29 ∞ 0.80 1.51633 64.1
30 ∞ 3.26
Image plane ∞

15th surface of aspheric data
K =-1.75172e+001 A 4=-9.98944e-005 A 6= 1.04317e-006 A 8=-1.14636e-008 A10= 8.13498e-011

18th side
K=-2.63607e-001 A 4=-1.49032e-005 A 6=-2.98459e-007 A 8= 1.57868e-009 A10= 3.37882e-012 A12=-1.42972e-013

19th side
K = 3.36428e+001 A 4= 3.43992e-005 A 6=-6.33319e-007 A 8= 1.22749e-008 A10=-1.10772e-010 A12= 3.59241e-013

22nd side
K =-4.40141e-001 A 4=-5.78878e-005 A 6=-1.37493e-006 A 8= 4.30944e-008 A10=-9.75740e-010 A12= 9.02113e-012

26th surface
K = 6.03496e+000 A 4=-3.37770e-004 A 6= 2.06232e-007 A 8=-3.65601e-006 A10= 2.93644e-007 A12=-1.29759e-008

27th side
K=0.00000e+000A4=-8.83192e-004

Various data Zoom ratio 38.50
Wide Angle Medium Telephoto Focal Length 4.42 49.08 170.14
F number 1.60 3.80 5.20
Half angle of view (degrees) 38.7 3.57 1.02
Image height 3.20 3.20 3.20
Overall lens length 130.00 130.00 130.00
BF 4.45 4.45 4.45

d9 0.70 44.70 55.71
d16 56.71 12.70 1.70
d19 3.54 5.90 10.30
d21 12.03 1.96 11.04
d24 6.77 9.24 1.00
d26 1.70 6.94 1.70

Lens group data group Starting surface Focal length
1 1 68.87
2 10 -10.66
3 17 20.32
4 20 -23.04
5 22 16.45
6 25 -13.79
7 27 19.63

Zoom trajectory data
B41=18.2682 B42=-55.7695 B43=95.0767
B44=-104.126 B45=52.3977 B46=0.9083

B61=-42.5485 B62=67.028 B63=-20.5297
B64=-53.3001 B65=80.9524 B66=-31.6021


(Numerical Example 7)
unit mm

Surface data surface number rd nd vd
1 97.575 1.50 1.80400 46.5
2 43.324 8.34 1.43875 94.7
3 -270.559 0.15
4 169.187 4.64 1.43875 94.7
5 -70.646 1.25 1.69680 55.5
6 -251.472 0.15
7 43.366 4.78 1.49700 81.5
8 -420.232 (variable)
9 -78.439 0.60 2.00100 29.1
10 12.444 4.72
11 -16.348 0.50 1.91082 35.3
12 491.796 3.95 1.95906 17.5
13 -14.325 0.15
14* -30.531 0.50 1.85135 40.1
15 108.610 (variable)
16 (Aperture) ∞ 0.50
17* 17.514 3.81 1.61881 63.9
18* -87.687 (variable)
19 37.056 0.70 2.00100 29.1
20 15.491 (variable)
21* 13.698 4.69 1.49710 81.6
22 -16.371 0.70 2.00100 29.1
23 -21.870 (variable)
24 77.784 0.50 1.82080 42.7
25* 11.528 (variable)
26 67.235 2.37 1.53110 55.9
27* -7.132 0.67
28 ∞ 0.80 1.51633 64.1
29 ∞ 3.30
Image plane ∞

14th surface of aspheric data
K = 1.52484e+000 A 4= 1.12385e-005 A 6= 1.57118e-007 A 8=-5.52513e-009 A10= 5.25293e-011

17th side
K = 5.20371e-001 A 4=-2.14326e-005 A 6=-6.09708e-007 A 8= 3.85409e-009 A10= 9.61034e-011 A12=-1.04085e-012

18th side
K =-1.98997e+001 A 4= 1.35023e-005 A 6=-8.00131e-007 A 8= 1.16920e-008 A10= 4.01490e-011 A12=-1.08039e-012

21st side
K =-4.57676e-001 A 4=-3.91231e-005 A 6=-2.94622e-007 A 8= 3.91944e-009 A10=-3.94012e-011 A12= 1.39346e-013

25th side
K = 6.87944e-001 A 4= 4.03532e-005 A 6=-6.95302e-006 A 8= 6.42026e-007 A10=-3.16127e-008 A12= 4.66273e-010

27th side
K = 0.00000e+000 A 4= 1.32939e-003 A 6=-1.88148e-005 A 8= 3.63400e-007

Various data Zoom ratio 70.00
Wide Angle Medium Telephoto Focal Length 3.93 64.65 275.16
F number 2.00 5.60 8.00
Half angle of view (degrees) 40.9 2.60 0.60
Image height 3.20 3.20 3.20
Overall lens length 151.09 151.09 151.09
BF 4.49 4.49 4.49

d8 0.70 39.64 49.38
d15 55.13 16.19 6.45
d18 5.36 9.04 16.67
d20 27.57 3.79 15.92
d23 11.36 16.61 1.00
d25 1.70 16.56 12.40

Lens group data group Starting surface Focal length
1 1 64.42
2 9 -8.56
3 16 23.92
4 19 -27.03
5 21 20.23
6 24 -16.55
7 26 12.28

Zoom trajectory data
B41=19.223 B42=-63.9456 B43=143.963
B44=-161.9712 B45=37.3846 B46=36.6528

B61=-50.7275 B62=82.4843 B63=-102.5533 B64=22.5162 B65=24.6001
B66=-39.7583 B67=147.2659 B68=26.6225 B69=-140.163 B610=19.0119


(Numerical Example 8)
unit mm

Surface data surface number rd nd vd
1 94.551 1.62 1.80400 46.5
2 37.687 7.54 1.49700 81.5
3 705.249 0.20
4 82.897 6.14 1.49700 81.5
5 -78.658 1.37 1.69680 55.5
6 ∞ 0.10
7 40.291 5.48 1.49700 81.5
8 -525.977 (variable)
9 58.833 0.69 1.83481 42.7
10 8.334 3.41
11 -1062.500 0.52 1.77250 49.6
12 13.075 3.21
13 -14.617 0.50 1.69680 55.5
14 -128.536 0.10
15 34.210 2.87 1.85478 24.8
16 -24.396 (variable)
17 43.434 4.96 1.49700 81.5
18 -17.057 0.60 1.69680 55.5
19 -44.084 0.50
20 ∞ 0.00
21 (aperture) ∞ (variable)
22 13.444 4.82 1.49700 81.5
23 34.673 0.26
24* 20.599 4.84 1.58313 59.4
25* -31.886 0.60
26 -57.038 0.60 1.74951 35.3
27 12.249 3.39 1.49700 81.5
28 -40.721 0.20
29 -122.365 3.62 1.49700 81.5
30 -7.534 0.50 1.69680 55.5
31 -24.633 (variable)
32 -40.135 1.14 1.95906 17.5
33 -13.708 0.50 1.83481 42.7
34 11.063 (variable)
35 10.630 4.05 1.60311 60.6
36 -9.090 0.50 1.84666 23.8
37 -17.329 1.50
38 ∞ 0.80 1.51500 70.0
39 ∞ 3.38
Image plane ∞

24th surface of aspheric data
K = 2.12553e-001 A 4= 4.71462e-006 A 6= 3.51123e-007 A 8=-3.12901e-009 A10= 3.73578e-011

25th side
K = 0.00000e+000 A 4= 1.13965e-004 A 6= 1.49256e-008 A 8=-9.61766e-009 A10= 9.71070e-011

Various data Zoom ratio 39.10
Wide Angle Medium Telephoto Focal Length 4.55 51.34 178.03
F number 1.65 3.20 4.94
Half angle of view (degrees) 35.4 3.56 1.05
Image height 3.20 3.20 3.20
Total lens length 133.12 133.12 133.12
BF 5.40 5.40 5.40

d8 0.65 38.37 46.65
d16 47.80 10.08 1.80
d21 10.26 2.22 2.39
d31 1.84 8.48 0.30
d34 2.10 3.49 11.50


Lens group data group Starting surface Focal length
1 1 62.68
2 9 -8.74
3 17 65.02
4 22 22.30
5 32 -10.93
6 35 13.30

Zoom trajectory data
B41=-28.9495 B42=-13.556 B43=178.2486 B44=-267.433 B45=52.9397
B46=145.774 B47=-26.0656 B48=54.5484 B49=-229.9484 B410=126.5757


(Numerical example 9)
unit mm

Surface data surface number rd nd vd
1 142.206 1.50 1.83400 37.2
2 57.154 4.30 1.48749 70.2
3 -434.246 0.15
4 241.469 2.62 1.48749 70.2
5 -129.459 1.25 1.80000 29.8
6 -456.604 0.15
7 54.477 3.02 1.69680 55.5
8 409.199 (variable)
9 -129.346 0.60 2.00100 29.1
10 13.696 5.51
11 -15.094 0.50 1.91082 35.3
12 -716.652 4.57 1.92286 18.9
13 -15.116 0.52
14* -19.963 0.50 1.85135 40.1
15 -41.157 (variable)
16 (Aperture) ∞ 0.50
17* 13.365 5.18 1.61881 63.9
18* -188.868 (variable)
19 27.478 0.70 2.00100 29.1
20 14.226 (variable)
21* 13.003 4.23 1.49710 81.6
22 -13.935 0.70 2.00100 29.1
23 -18.502 (variable)
24 44.031 0.50 1.82080 42.7
25* 10.366 (variable)
26 64.155 1.62 1.53110 55.9
27* -18.071 0.67
28 ∞ 0.80 1.51633 64.1
29 ∞ 3.29
Image plane ∞

14th surface of aspheric data
K =-8.41939e+000 A 4=-1.25082e-004 A 6= 9.60415e-007 A 8=-7.39534e-009 A10= 2.68057e-011

17th side
K = 3.25812e-001 A 4=-4.05611e-005 A 6=-6.90017e-007 A 8= 3.51883e-009 A10=-1.62418e-011 A12=-1.32957e-013

18th side
K =-1.22058e+003 A 4= 7.54439e-006 A 6=-7.74394e-007 A 8= 1.66246e-008 A10=-1.55754e-010 A12= 5.86124e-013

21st side
K =-6.70793e-001 A 4=-5.29949e-005 A 6=-1.40125e-006 A 8= 5.20571e-008 A10=-1.23449e-009 A12= 1.11866e-011

25th side
K = 1.32944e+000 A 4=-1.12160e-004 A 6= 1.39468e-005 A 8=-1.83278e-006 A10= 9.43187e-008 A12=-1.83677e-009

27th side
K = 0.00000e+000 A 4=-1.10572e-004 A 6= 4.24796e-006 A 8=-2.39266e-007

Various data Zoom ratio 38.50
Wide Angle Medium Telephoto Focal Length 4.42 53.27 170.00
F number 1.60 3.80 5.20
Half angle of view (degrees) 41.7 3.42 1.07
Image height 3.20 3.20 3.20
Overall lens length 130.00 130.00 130.00
BF 4.49 4.49 4.49

d8 0.70 46.82 58.34
d15 58.65 12.53 1.00
d18 1.00 2.67 5.26
d20 17.99 3.40 6.22
d23 6.58 8.25 4.02
d25 1.70 12.94 11.77

Lens group data group Starting surface Focal length
1 1 75.07
2 9 -10.61
3 16 20.37
4 19 -30.27
5 21 18.48
6 24 -16.63
7 26 26.73

Zoom trajectory data
B41=18.1599 B42=-61.3797 B43=134.206
B44=-151.1273 B45=41.7034 B46=22.6971

B61=-58.451 B62=87.9398 B63=-90.5556 B64=41.0952 B65=69.95
B66=-128.6733 B67=165.9398 B68=-21.0821 B69=-130.2882 B610=54.059


Table 1 shows the relationship between each conditional expression described above and each numerical example.

L0 zoom lens L1 first lens group L2 second lens group LR rear group

Claims (15)

A zoom lens having a rear group including a first lens group with positive refractive power, a second lens group with negative refractive power, and four or more lens groups arranged in order from the object side to the image side,
having an aperture stop,
During zooming, the first lens group is stationary, and two or more lens groups arranged closer to the image side than the aperture stop move to change the distance between adjacent lens groups,
The first lens group has five or more lenses including a plurality of positive lenses ,
DL1 is the distance on the optical axis from the most object-side lens surface to the most image-side lens surface of the first lens group, fw is the focal length of the zoom lens at the wide-angle end, and the focal point of the zoom lens at the telephoto end When the distance is ft and the minimum Abbe number of the material of the plurality of positive lenses is νd1min ,
0.05<DL1/ft<0.40
25.0<ft/fw<200.0
55<νd1min
A zoom lens characterized by satisfying the following conditional expression: A zoom lens having a rear group including a first lens group with positive refractive power, a second lens group with negative refractive power, and four or more lens groups arranged in order from the object side to the image side,
having an aperture stop,
During zooming, the first lens group is stationary, and two or more lens groups arranged closer to the image side than the aperture stop move to change the distance between adjacent lens groups,
The first lens group has five or more lenses,
The rear group includes a third lens group with positive refractive power, a fourth lens group with negative refractive power, a fifth lens group with positive refractive power, and a negative refractive power, arranged in order from the object side to the image side. It consists of a sixth lens group of and a seventh lens group of positive refractive power,
DL1 is the distance on the optical axis from the most object-side lens surface to the most image-side lens surface of the first lens group, fw is the focal length of the zoom lens at the wide-angle end, and the focal point of the zoom lens at the telephoto end When the distance is ft,
0.05<DL1/ft<0.40
25.0<ft/fw<200.0
A zoom lens characterized by satisfying the following conditional expression: A zoom lens having a rear group including a first lens group with positive refractive power, a second lens group with negative refractive power, and four or more lens groups arranged in order from the object side to the image side,
having an aperture stop,
During zooming, the first lens group is stationary, and two or more lens groups arranged closer to the image side than the aperture stop move to change the distance between adjacent lens groups,
The first lens group has five or more lenses,
The rear group includes a third lens group with positive refractive power, a fourth lens group with positive refractive power, a fifth lens group with negative refractive power, and a positive refractive power, arranged in order from the object side to the image side. is composed of a sixth lens group of
DL1 is the distance on the optical axis from the most object-side lens surface to the most image-side lens surface of the first lens group, fw is the focal length of the zoom lens at the wide-angle end, and the focal point of the zoom lens at the telephoto end When the distance is ft,
0.05<DL1/ft<0.40
25.0<ft/fw<200.0
A zoom lens characterized by satisfying the following conditional expression: When the focal length of the first lens group is f1 and the focal length of the second lens group is f2,
-10.0<f1/f2<-5.0
4. The zoom lens according to any one of claims 1 to 3, wherein the following conditional expression is satisfied. When the back focus at the wide-angle end is BFw,
0.3<BFw/fw<3.0
5. The zoom lens according to any one of claims 1 to 4, wherein the following conditional expression is satisfied. When the distance on the optical axis from the lens surface closest to the object to the image plane is TD,
0.3<TD/ft<1.4
6. The zoom lens according to any one of claims 1 to 5 , wherein the following conditional expression is satisfied. When the focal length of the second lens group is f2,
-5.0<f2/fw<-1.0
7. The zoom lens according to any one of claims 1 to 6 , wherein the following conditional expression is satisfied. When the focal length of the first lens group is f1,
0.1<f1/ft<1.0
8. The zoom lens according to any one of claims 1 to 7 , wherein the following conditional expression is satisfied. 9. The zoom lens according to claim 1 , wherein said first lens group has three or more positive lenses. 10. The zoom lens according to any one of claims 1 to 9 , wherein the second lens group is arranged closer to the object side than the aperture stop. An imaging apparatus, comprising: the zoom lens according to any one of claims 1 to 10 ; and an imaging device for receiving an image formed by the zoom lens. An imaging system, comprising: the zoom lens according to any one of claims 1 to 10 ; and a control section for controlling the zoom lens. 13. The imaging system according to claim 12 , wherein the control section transmits a control signal for controlling the zoom lens. 14. The imaging system according to claim 12 , wherein the control section has an operation section for operating the zoom lens. 15. The imaging system according to any one of claims 12 to 14 , further comprising a display section for displaying information about zooming of said zoom lens.

Images