WO2013105190A1

WO2013105190A1 - Zoom lens system, imaging device, and camera

Info

Publication number: WO2013105190A1
Application number: PCT/JP2012/008241
Authority: WO
Inventors: 岩下　勉; 朴　一武; 靖典東地
Original assignee: パナソニック株式会社
Priority date: 2012-01-13
Filing date: 2012-12-25
Publication date: 2013-07-18
Also published as: JP2013145286A

Abstract

A zoom lens system that: has a plurality of lens groups configured from one or more lens elements; is provided with two or more aperture stops; has one or more lens elements positioned between the two or more aperture stops; and is characterized in that when zooming from a wide-angle end toward a telescopic end during imaging, the amount of light is adjusted by selecting one of the two or more aperture stops according to the zoom position.

Description

Zoom lens system, imaging device and camera

The present disclosure relates to a zoom lens system, an imaging device, and a camera.

Demand for downsizing and high performance of a camera having an image sensor that performs photoelectric conversion (hereinafter simply referred to as a digital camera) such as a digital still camera or a digital video camera is extremely strong. In particular, a compact digital camera equipped with a zoom lens system having a high zooming ratio is strongly demanded for its convenience. Furthermore, there is a need for a zoom lens system having a wide angle range with a wide shooting range. As such a zoom lens system, for example, various zoom lens systems having a negative lead three-group structure and a positive lead four-group structure have been proposed.

In Patent Document 1, a variable aperture for determining an open F-number is arranged on the object side of a second lens group having a three-group configuration of the negative lead and having a positive refractive power. A zoom lens is disclosed in which a mechanical aperture for cutting harmful rays is arranged on the image side.

JP 2010-243637 A

The present disclosure not only has a high resolution but also a zooming ratio as high as 5 times or more, and also has a large angle of view at the wide-angle end and can be sufficiently adapted to wide-angle shooting while being compact. Provided is a zoom lens system capable of forming an image having a desired brightness in accordance with a zoom position. The present disclosure also provides an imaging apparatus including the zoom lens system and a thin and compact camera including the imaging apparatus.

The zoom lens system in the present disclosure is:
Having a plurality of lens groups composed of at least one lens element;
With at least two aperture stops,
At least one lens element is disposed between the at least two aperture stops;
During zooming from the wide-angle end to the telephoto end during imaging, one of the at least two aperture stops is selected and the amount of light is adjusted according to the zoom position.

An imaging apparatus according to the present disclosure
An imaging apparatus capable of outputting an optical image of an object as an electrical image signal,
A zoom lens system that forms an optical image of the object;
An image sensor that converts an optical image formed by the zoom lens system into an electrical image signal;
The zoom lens system is
Having a plurality of lens groups composed of at least one lens element;
With at least two aperture stops,
At least one lens element is disposed between the at least two aperture stops;
During zooming from the wide-angle end to the telephoto end during imaging, one of the at least two aperture stops is selected and the amount of light is adjusted according to the zoom position.

The camera in the present disclosure is
A camera that converts an optical image of an object into an electrical image signal, and displays and stores the converted image signal;
An image pickup apparatus including a zoom lens system that forms an optical image of an object, and an image sensor that converts an optical image formed by the zoom lens system into an electrical image signal;
The zoom lens system is
Having a plurality of lens groups composed of at least one lens element;
With at least two aperture stops,
At least one lens element is disposed between the at least two aperture stops;
During zooming from the wide-angle end to the telephoto end during imaging, one of the at least two aperture stops is selected and the amount of light is adjusted according to the zoom position.

The zoom lens system according to the present disclosure not only has high resolution, but also has a high zooming ratio of about 5 times or more, and also has a large angle of view at the wide-angle end and is small enough to be used for wide-angle shooting. In addition, it is possible to form an image having a desired brightness according to the zoom position.

FIG. 1 is a lens arrangement diagram illustrating an infinitely focused state of the zoom lens system according to Embodiment 1 (Numerical Example 1). FIG. 2 is a longitudinal aberration diagram of the zoom lens system according to Numerical Example 1 when the zoom lens system is in focus at infinity. FIG. 3 is a lens arrangement diagram illustrating an infinitely focused state of the zoom lens system according to Embodiment 2 (Numerical Example 2). FIG. 4 is a longitudinal aberration diagram of the zoom lens system according to Numerical Example 2 when the zoom lens system is in focus at infinity. FIG. 5 is a lens arrangement diagram illustrating an infinitely focused state of the zoom lens system according to Embodiment 3 (Numerical Example 3). FIG. 6 is a longitudinal aberration diagram of the zoom lens system according to Numerical Example 3 when the zoom lens system is in focus at infinity. FIG. 7 is a lens arrangement diagram illustrating an infinitely focused state of the zoom lens system according to Embodiment 4 (Numerical Example 4). FIG. 8 is a longitudinal aberration diagram of the zoom lens system according to Numerical Example 4 when the zoom lens system is in focus at infinity. FIG. 9 is a schematic configuration diagram of a digital still camera according to the fifth embodiment.

Hereinafter, embodiments will be described in detail with reference to the drawings as appropriate. However, more detailed explanation than necessary may be omitted. For example, detailed descriptions of already well-known matters and repeated descriptions for substantially the same configuration may be omitted. This is to avoid the following description from becoming unnecessarily redundant and to facilitate understanding by those skilled in the art.

In addition, the inventors provide the accompanying drawings and the following description in order for those skilled in the art to fully understand the present disclosure, and are not intended to limit the subject matter described in the claims. Absent.

(Embodiments 1 to 4)
1, 3, 5, and 7 are lens arrangement diagrams of the zoom lens systems according to Embodiments 1 to 4, respectively, and all represent the zoom lens system in an infinitely focused state.

In each figure, (a) shows a lens configuration at the wide angle end (shortest focal length state: focal length f _W ), and (b) shows an intermediate position (intermediate focal length state: focal length f _M = √ (f _W * f). The lens configuration of _T )) and (c) show the lens configuration at the telephoto end (longest focal length state: focal length f _T ). Also, in each figure, the broken line arrows provided between FIGS. (A) and (b) are obtained by connecting the positions of the lens groups in the wide-angle end, the intermediate position, and the telephoto end in order from the top. Straight line. The wide-angle end and the intermediate position, and the intermediate position and the telephoto end are simply connected by a straight line, which is different from the actual movement of each lens group.

Further, in each figure, an arrow attached to the lens group represents focusing from an infinitely focused state to a close object focused state. That is, FIGS. 1, 3, 5, and 7 show directions in which a third lens group G3, which will be described later, moves during focusing from an infinitely focused state to a close object focused state.

In the zoom lens systems according to

Embodiments

1 and 2, in order from the object side to the image side, the first lens group G1 having negative power, the second lens group G2 having positive power, and the positive power And a third lens group G3. During zooming, the distance between the lens groups, that is, the distance between the first lens group G1 and the second lens group G2, and the distance between the second lens group G2 and the third lens group G3 are all changed. All lens groups move in the direction along the optical axis. The zoom lens system according to each embodiment can reduce the size of the entire lens system while maintaining high optical performance by arranging these lens groups in a desired power arrangement.

In the zoom lens systems according to

Embodiments

3 and 4, the first lens group G1 having a positive power, the second lens group G2 having a negative power, and the positive power in order from the object side to the image side. And a fourth lens group G4 having a positive power. During zooming, the distance between the lens groups, that is, the distance between the first lens group G1 and the second lens group G2, the distance between the second lens group G2 and the third lens group G3, and the third lens group G3 and the third lens group G3. All the lens groups are moved in the direction along the optical axis so that the intervals between the four lens groups G4 are all changed. The zoom lens system according to each embodiment can reduce the size of the entire lens system while maintaining high optical performance by arranging these lens groups in a desired power arrangement.

In FIGS. 1, 3, 5 and 7, an asterisk * attached to a specific surface indicates that the surface is aspherical. In each figure, a symbol (+) and a symbol (−) attached to a symbol of each lens group correspond to a power symbol of each lens group. In each figure, the straight line described on the rightmost side represents the position of the image plane S. The object side of the image plane S (FIGS. 1 and 3: the image plane S and the most image side lens surface of the third lens group G3). 5 and 7: between the image plane S and the most image side lens surface of the fourth lens group G4), a parallel flat plate P equivalent to an optical low-pass filter, a face plate of an image sensor, or the like is provided. It has been.

(Embodiment 1)
As shown in FIG. 1, the first lens group G1 includes, in order from the object side to the image side, a negative meniscus first lens element L1 having a convex surface facing the object side, and a positive meniscus having a convex surface facing the object side. The second lens element L2 having a shape. Among these, the second lens element L2 has two aspheric surfaces.

The second lens group G2 includes, in order from the object side to the image side, a biconvex third lens element L3, a biconcave fourth lens element L4, and a negative meniscus second lens element with a convex surface facing the object side. 5 lens elements L5. Among these, the third lens element L3 and the fourth lens element L4 are cemented, and in the surface data in the corresponding numerical value example described later, the adhesion between the third lens element L3 and the fourth lens element L4. Surface number 7 is given to the agent layer. The fifth lens element L5 has two aspheric surfaces.

The third lens group G3 comprises solely a positive meniscus sixth lens element L6 with the convex surface facing the image side. The sixth lens element L6 has two aspheric surfaces.

An aperture stop 1 (surface number 5 in the surface data in the corresponding numerical example described later) A1 is provided immediately on the object side of the third lens element L3, and immediately on the object side of the fifth lens element L5, An aperture stop 2 (surface number 10 in the surface data in the corresponding numerical example described later) A2 is provided. The aperture stop 1A1 and the aperture stop 2A2 move on the optical axis integrally with the second lens group G2 during zooming from the wide-angle end to the telephoto end during imaging.

A parallel plate P is provided on the object side of the image plane S, that is, between the image plane S and the sixth lens element L6.

During zooming from the wide-angle end to the telephoto end during imaging, the first lens group G1 moves toward the object side along a locus convex to the image side, and the second lens group G2 moves toward the object side substantially monotonously. The third lens group G3 moves to the image side substantially monotonously. That is, during zooming, all the lens groups are placed on the optical axis so that the distance between the first lens group G1 and the second lens group G2 changes and the distance between the second lens group G2 and the third lens group G3 increases. Move along each.

In focusing from the infinitely focused state to the close object focused state, the third lens group G3 moves toward the object side along the optical axis.

By moving the entire second lens group G2 in a direction orthogonal to the optical axis, it is possible to correct image point movement due to vibration of the entire system. That is, when correcting the image point movement due to the vibration of the entire system, the entire second lens group G2 moves in a direction perpendicular to the optical axis, thereby suppressing the enlargement of the entire zoom lens system and making it compact. However, it is possible to optically correct image blur due to camera shake, vibration, etc. while maintaining excellent imaging characteristics with small decentration coma and decentering astigmatism.

(Embodiment 2)
As shown in FIG. 3, the first lens group G1 includes, in order from the object side to the image side, a negative meniscus first lens element L1 having a convex surface facing the object side, and a positive meniscus having a convex surface facing the object side. The second lens element L2 having a shape. Among these, the second lens element L2 has two aspheric surfaces.

(Embodiment 3)
As shown in FIG. 5, the first lens group G1 includes, in order from the object side to the image side, a negative meniscus first lens element L1 having a convex surface facing the object side, and a biconvex second lens element L2. It consists of. The first lens element L1 and the second lens element L2 are cemented, and in the surface data in the corresponding numerical value example described later, the adhesive layer between the first lens element L1 and the second lens element L2 is used. Surface number 2 is given. The second lens element L2 has an aspheric image side surface.

The second lens group G2 includes, in order from the object side to the image side, a biconcave third lens element L3, a biconcave fourth lens element L4, and a positive meniscus second lens element with a convex surface facing the object side. 5 lens elements L5. Among these, the fourth lens element L4 has an aspheric object side surface.

The third lens group G3 includes, in order from the object side to the image side, a biconvex sixth lens element L6, a positive meniscus seventh lens element L7 with a convex surface facing the object side, and a convex surface facing the object side. And a negative meniscus eighth lens element L8. Among these, the seventh lens element L7 and the eighth lens element L8 are cemented, and in the surface data in the corresponding numerical value example described later, the adhesion between the seventh lens element L7 and the eighth lens element L8. Surface number 16 is given to the agent layer. The sixth lens element L6 has two aspheric surfaces.

The fourth lens group G4 comprises solely a biconvex ninth lens element L9. The ninth lens element L9 has two aspheric surfaces.

An aperture stop 1 (surface number 11 in the surface data in the corresponding numerical example described later) A1 is provided immediately on the object side of the sixth lens element L6, and immediately on the object side of the seventh lens element L7, An aperture stop 2 (surface number 14 in the surface data in the corresponding numerical example described later) A2 is provided. The aperture stop 1A1 and the aperture stop 2A2 move on the optical axis integrally with the third lens group G3 during zooming from the wide-angle end to the telephoto end during imaging.

A parallel plate P is provided on the object side of the image plane S, that is, between the image plane S and the ninth lens element L9.

During zooming from the wide-angle end to the telephoto end during imaging, the first lens group G1 moves to the object side substantially monotonously, and the second lens group G2 slightly draws a slightly convex locus on the object side. The third lens group G3 moves toward the object side with a convex locus on the object side, and the fourth lens group G4 moves toward the image side substantially monotonously. That is, during zooming, the distance between the first lens group G1 and the second lens group G2 changes, the distance between the second lens group G2 and the third lens group G3 changes, and the third lens group G3 and the fourth lens. All the lens groups move along the optical axis so that the distance from the group G4 increases.

By moving the entire third lens group G3 in a direction perpendicular to the optical axis, it is possible to correct image point movement due to vibration of the entire system. That is, when correcting the image point movement due to the vibration of the entire system, the entire third lens group G3 moves in a direction perpendicular to the optical axis, thereby suppressing the enlargement of the entire zoom lens system and making it compact. However, it is possible to optically correct image blur due to camera shake, vibration, etc. while maintaining excellent imaging characteristics with small decentration coma and decentering astigmatism.

(Embodiment 4)
As shown in FIG. 7, the first lens group G1 includes, in order from the object side to the image side, a negative meniscus first lens element L1 having a convex surface facing the object side, and a biconvex second lens element L2. It consists of. The first lens element L1 and the second lens element L2 are cemented, and in the surface data in the corresponding numerical value example described later, the adhesive layer between the first lens element L1 and the second lens element L2 is used. Surface number 2 is given. The second lens element L2 has an aspheric image side surface.

A zoom lens system such as the zoom lens systems according to Embodiments 1 to 4 includes at least two aperture stops, and at least one lens element is disposed between the at least two aperture stops. Then, during zooming from the wide-angle end to the telephoto end during imaging, one of these at least two aperture stops is selected and the amount of light is adjusted according to the zoom position. That is, in the zoom lens system according to the present disclosure, at the time of zooming, one aperture stop selected from a plurality of aperture stops so that an image having a desired brightness can be formed at that zoom position. The light quantity is adjusted by one aperture stop selected from a plurality of aperture stops so that an image having a desired brightness can be formed at another zoom position. As described above, the zoom lens system according to the present disclosure includes at least two aperture stops that can contribute to the F-number. Therefore, the light amount can be appropriately adjusted according to the zoom position, and the zoom position can be adjusted according to the zoom position. An image having a desired brightness can be formed.

In the zoom lens systems according to Embodiments 1 to 4, the zoom lens system was selected at the wide-angle end during zooming from the wide-angle end to the telephoto end during imaging, as shown in various data in the corresponding numerical examples described later. The aperture stop is different from the aperture stop selected at the telephoto end. In the zoom lens systems according to Embodiments 1 to 4, the aperture stop 1A1 is selected so that the F-number is small at the wide-angle end, that is, the amount of light is large and a bright image is formed, and the F-number is large at the telephoto end. That is, the aperture stop 2A2 is selected so that the amount of light is small and a dark image is formed compared to the wide-angle end.

Each lens group constituting the zoom lens system according to Embodiments 1 to 4 includes a refractive lens element that deflects incident light by refraction (that is, a type in which deflection is performed at an interface between media having different refractive indexes) However, the present invention is not limited to this. For example, a diffractive lens element that deflects incident light by diffraction, a refractive / diffractive hybrid lens element that deflects incident light by a combination of diffraction and refraction, and a refractive index that deflects incident light by the refractive index distribution in the medium Each lens group may be composed of a distributed lens element or the like. In particular, in a refractive / diffractive hybrid lens element, forming a diffractive structure at the interface of media having different refractive indexes is advantageous because the wavelength dependency of diffraction efficiency is improved.

As described above, Embodiments 1 to 4 have been described as examples of the technology disclosed in the present application. However, the technology in the present disclosure is not limited to this, and can also be applied to an embodiment in which changes, replacements, additions, omissions, and the like are appropriately performed.

(Embodiment 5)
FIG. 9 is a schematic configuration diagram of a digital still camera according to the fifth embodiment. In FIG. 9, the digital still camera includes an image pickup apparatus including a zoom lens system 1 and an image pickup device 2 that is a CCD, a liquid crystal monitor 3, and a housing 4. As the zoom lens system 1, the zoom lens system according to Embodiment 1 is used. In FIG. 9, the zoom lens system 1 includes a first lens group G1, a second lens group G2 including an aperture stop 1A1 and an aperture stop 2A2, and a third lens group G3. In the housing 4, the zoom lens system 1 is disposed on the front side, and the imaging element 2 is disposed on the rear side of the zoom lens system 1. A liquid crystal monitor 3 is disposed on the rear side of the housing 4, and an optical image of the subject by the zoom lens system 1 is formed on the image plane S.

The lens barrel is composed of a main lens barrel 5, a movable lens barrel 6, and a cylindrical cam 7. When the cylindrical cam 7 is rotated, the first lens group G1, the aperture stop 1A1, the aperture stop 2A2, the second lens group G2, and the third lens group G3 move to predetermined positions with the image sensor 2 as a reference, and a wide angle. Zooming from the end to the telephoto end can be performed. The third lens group G3 is movable in the optical axis direction by a focus adjustment motor.

Thus, by using the zoom lens system according to Embodiment 1 for a digital still camera, it is possible to provide a small digital still camera that has a high ability to correct resolution and curvature of field and has a short overall lens length when not in use. it can. In the digital still camera shown in FIG. 9, any of the zoom lens systems according to the second to fourth embodiments may be used instead of the zoom lens system according to the first embodiment. Further, the optical system of the digital still camera shown in FIG. 9 can be used for a digital video camera for moving images. In this case, not only a still image but also a moving image with high resolution can be taken.

In the digital still camera according to the fifth embodiment, the zoom lens system according to the first to fourth embodiments is shown as the zoom lens system 1, but these zoom lens systems do not use the entire zooming area. May be. That is, a range in which the optical performance is ensured may be cut out according to a desired zooming area, and used as a zoom lens system having a lower magnification than the zoom lens system described in the first to fourth embodiments.

Furthermore, in the fifth embodiment, an example in which the zoom lens system is applied to a so-called collapsible lens barrel is shown, but the present invention is not limited to this. For example, a prism having an internal reflection surface or a surface reflection mirror may be disposed at an arbitrary position such as in the first lens group G1, and the zoom lens system may be applied to a so-called bent lens barrel. Further, in the fifth embodiment, a part of the lens groups constituting the zoom lens system such as the entire second lens group G2 and a part of the second lens group G2 are retracted from the optical axis when retracted. A zoom lens system may be applied to the sliding lens barrel.

As described above, the fifth embodiment has been described as an example of the technique disclosed in the present application. However, the technology in the present disclosure is not limited to this, and can also be applied to an embodiment in which changes, replacements, additions, omissions, and the like are appropriately performed.

In addition, an image pickup apparatus including the zoom lens system according to Embodiments 1 to 4 described above and an image pickup device such as a CCD or a CMOS is used as a camera for a portable information terminal such as a smartphone, a monitoring camera for a monitoring system, a Web The present invention can also be applied to cameras, in-vehicle cameras, and the like.

Hereinafter, numerical examples in which the zoom lens systems according to Embodiments 1 to 4 are specifically implemented will be described. In each numerical example, the unit of length in the table is “mm”, and the unit of angle of view is “°”. In each numerical example, r is a radius of curvature, d is a surface interval, nd is a refractive index with respect to the d line, vd is an Abbe number with respect to the d line, and the diameters of the diaphragm 1 and the diaphragm 2 are effective diameters. In each numerical example, the surface marked with * is an aspherical surface, and the aspherical shape is defined by the following equation.

here,
Z: distance from a point on the aspheric surface having a height h from the optical axis to the tangent plane of the aspheric vertex,
h: height from the optical axis,
r: vertex radius of curvature,
κ: conic constant,
An: n-order aspherical coefficient.

2, 4, 6 and 8 are longitudinal aberration diagrams of the zoom lens systems according to Numerical Examples 1 to 4, respectively.

In each longitudinal aberration diagram, (a) shows the aberration at the wide angle end, (b) shows the intermediate position, and (c) shows the aberration at the telephoto end. Each longitudinal aberration diagram shows spherical aberration (SA (mm)), astigmatism (AST (mm)), and distortion (DIS (%)) in order from the left side. In the spherical aberration diagram, the vertical axis represents the F number (indicated by F in the figure), the solid line is the d line (d-line), the short broken line is the F line (F-line), and the long broken line is the C line (C- line). In the astigmatism diagram, the vertical axis represents the image height (indicated by H in the figure), the solid line represents the sagittal plane (indicated by s), and the broken line represents the meridional plane (indicated by m in the figure). is there. In the distortion diagram, the vertical axis represents the image height (indicated by H in the figure).

(Numerical example 1)
The zoom lens system of Numerical Example 1 corresponds to Embodiment 1 shown in FIG. Table 1 shows surface data of the zoom lens system of Numerical Example 1, Table 2 shows aspheric data, and Table 3 shows various data.

Table 1 (surface data)

Surface number r d nd vd
Object ∞
1 196.45960 0.30000 1.72916 54.7
2 5.98460 1.86770
3 * 8.66670 1.53070 1.63550 23.9
4 * 14.84410 variable
5 (Aperture 1) ∞ -0.30000
6 4.58530 1.58970 1.72916 54.7
7 -8.94400 0.00500 1.56732 42.8
8 -8.94400 0.30000 1.62004 36.3
9 36.01690 0.49620
10 (Aperture 2) ∞ 0.00000
11 * 8.37030 1.28650 1.63550 23.9
12 * 3.69800 Variable
13 * -35.59240 1.43840 1.54310 56.0
14 * -7.00810 Variable
15 ∞ 0.50000 1.51680 64.2
16 ∞ 0.37000
17 ∞ (BF)
Image plane ∞

Table 2 (Aspheric data)

3rd surface K = 0.00000E + 00, A4 = -1.96013E-04, A6 = 8.08283E-06, A8 = -1.38859E-06
A10 = 5.09613E-08, A12 = -4.79626E-11, A14 = 1.28647E-11, A16 = -1.00260E-12
4th surface K = 0.00000E + 00, A4 = -4.49795E-04, A6 = 2.80911E-06, A8 = -1.82439E-06
A10 = 1.18077E-07, A12 = -2.34888E-09, A14 = -9.27771E-18, A16 = 1.24568E-16
11th surface K = 0.00000E + 00, A4 = -2.78446E-03, A6 = -2.52712E-04, A8 = 8.93720E-06
A10 = 2.13422E-05, A12 = -7.27526E-06, A14 = 1.74476E-07, A16 = 1.16882E-07
12th surface K = 0.00000E + 00, A4 = 1.43930E-04, A6 = 2.45586E-04, A8 = -7.63582E-05
A10 = -2.11697E-05, A12 = 1.03466E-05, A14 = 5.08150E-06, A16 = -1.72649E-06
13th surface K = 0.00000E + 00, A4 = 6.59545E-04, A6 = -7.68656E-05, A8 = 7.03087E-06
A10 = -2.67241E-07, A12 = 4.96282E-09, A14 = 1.20119E-18, A16 = 5.61307E-17
14th surface K = 0.00000E + 00, A4 = 1.81052E-03, A6 = -1.03965E-04, A8 = 8.50713E-06
A10 = -3.50264E-07, A12 = 7.11113E-09, A14 = -7.86620E-19, A16 = -3.92809E-17

Table 3 (various data)

Zoom ratio 4.60994
Wide angle Medium telephoto Focal length 4.4515 9.2575 20.5212
F number 2.66857 3.93480 6.80005
Angle of view 42.0647 22.4483 10.4203
Image height 3.4000 3.8770 3.8770
Total lens length 30.6310 26.1886 31.7260
BF 0.04090 -0.00776 -0.01299
d4 14.7223 5.6089 0.6000
d12 3.0287 8.1765 18.7176
d14 3.4549 3.0269 3.0372
Entrance pupil position 7.1348 4.9579 2.6926
Exit pupil position -13.0677 -39.0826 56.0917
Front principal point 10.0747 12.0222 30.7198
Rear principal point position 26.1795 16.9311 11.2048
Aperture 1 (diameter) 4.1000 4.1000 4.1000
Aperture 2 (diameter) 3.3600 3.3600 3.3600
* Aperture 1 is for the wide-angle end, and aperture 2 is for the middle and telephoto ends.

Single lens data Lens Start surface Focal length 1 1 -8.4710
2 3 29.8926
3 6 4.3739
4 8 -11.5259
5 11 -11.6736
6 13 15.7880

Zoom lens group data Group Start surface Focal length Lens configuration length Front principal point position Rear principal point position 1 1 -12.19926 3.69840 -0.09212 0.68998
2 5 8.89034 3.37740 -2.80370 -0.37274
3 13 15.78795 1.43840 1.14049 1.66296

Zoom lens group magnification group Start surface Wide angle Medium telephoto 1 1 0.00000 0.00000 0.00000
2 5 -0.48752 -0.97455 -2.16119
3 13 0.74849 0.77868 0.77835

(Numerical example 2)
The zoom lens system of Numerical Example 2 corresponds to Embodiment 2 shown in FIG. Table 4 shows surface data of the zoom lens system of Numerical Example 2, Table 5 shows aspheric data, and Table 6 shows various data.

Table 4 (surface data)

Surface number r d nd vd
Object ∞
1 196.45960 0.30000 1.72916 54.7
2 5.98460 1.86770
3 * 8.66670 1.53070 1.63550 23.9
4 * 14.84410 variable
5 (Aperture 1) ∞ -0.30000
6 4.58530 1.58970 1.72916 54.7
7 -8.94400 0.00500 1.56732 42.8
8 -8.94400 0.30000 1.62004 36.3
9 36.01690 0.49620
10 (Aperture 2) ∞ 0.00000
11 * 8.37030 1.28650 1.63550 23.9
12 * 3.69800 Variable
13 * -35.59240 1.43840 1.54310 56.0
14 * -7.00810 Variable
15 ∞ 0.50000 1.51680 64.2
16 ∞ 0.37000
17 ∞ (BF)
Image plane ∞

Table 5 (Aspheric data)

3rd surface K = 0.00000E + 00, A4 = -1.96013E-04, A6 = 8.08283E-06, A8 = -1.38859E-06
A10 = 5.09613E-08, A12 = -4.79626E-11, A14 = 1.28647E-11, A16 = -1.00260E-12
4th surface K = 0.00000E + 00, A4 = -4.49795E-04, A6 = 2.80911E-06, A8 = -1.82439E-06
A10 = 1.18077E-07, A12 = -2.34888E-09, A14 = -9.27771E-18, A16 = 1.24568E-16
11th surface K = 0.00000E + 00, A4 = -2.78446E-03, A6 = -2.52712E-04, A8 = 8.93720E-06
A10 = 2.13422E-05, A12 = -7.27526E-06, A14 = 1.74476E-07, A16 = 1.16882E-07
12th surface K = 0.00000E + 00, A4 = 1.43930E-04, A6 = 2.45586E-04, A8 = -7.63582E-05
A10 = -2.11697E-05, A12 = 1.03466E-05, A14 = 5.08150E-06, A16 = -1.72649E-06
13th surface K = 0.00000E + 00, A4 = 6.59545E-04, A6 = -7.68656E-05, A8 = 7.03087E-06
A10 = -2.67241E-07, A12 = 4.96282E-09, A14 = 1.20119E-18, A16 = 5.61307E-17
14th surface K = 0.00000E + 00, A4 = 1.81052E-03, A6 = -1.03965E-04, A8 = 8.50713E-06
A10 = -3.50264E-07, A12 = 7.11113E-09, A14 = -7.86620E-19, A16 = -3.92809E-17

Table 6 (various data)

Zoom ratio 4.60994
Wide angle Medium telephoto Focal length 4.4515 9.2575 20.5212
F number 2.66857 3.86762 6.65393
Angle of View 42.0642 22.4488 10.4205
Image height 3.4000 3.8770 3.8770
Total lens length 30.6310 26.1886 31.7260
BF 0.04090 -0.00776 -0.01299
d4 14.7223 5.6089 0.6000
d12 3.0287 8.1765 18.7176
d14 3.4549 3.0269 3.0372
Entrance pupil position 7.1348 4.9579 2.6926
Exit pupil position -13.0677 -39.0826 56.0917
Front principal point 10.0747 12.0222 30.7198
Rear principal point position 26.1795 16.9311 11.2048
Aperture 1 (diameter) 4.1000 4.1000 4.1000
Aperture 2 (diameter) 3.4400 3.4400 3.4400
* Aperture 1 is a wide-angle / intermediate aperture, and aperture 2 is a telephoto end.

Single lens data Lens Start surface Focal length 1 1 -8.4710
2 3 29.8926
3 6 4.3739
4 8 -11.5259
5 11 -11.6736
6 13 15.7880

Zoom lens group data Group Start surface Focal length Lens configuration length Front principal point position Rear principal point position 1 1 -12.19926 3.69840 -0.09212 0.68998
2 5 8.89034 3.37740 -2.80370 -0.37274
3 13 15.78795 1.43840 1.14049 1.66296

Zoom lens group magnification group Start surface Wide angle Medium telephoto 1 1 0.00000 0.00000 0.00000
2 5 -0.48752 -0.97455 -2.16119
3 13 0.74849 0.77868 0.77835

(Numerical Example 3)
The zoom lens system of Numerical Example 3 corresponds to Embodiment 3 shown in FIG. Table 7 shows surface data of the zoom lens system of Numerical Example 3, Table 8 shows aspheric data, and Table 9 shows various data.

Table 7 (surface data)

Surface number r d nd vd
Object ∞
1 15.33220 0.50000 1.92286 20.9
2 12.03590 0.01000 1.56732 42.8
3 12.03590 3.30000 1.58332 59.1
4 * -143.37120 Variable
5 -113.96490 0.30000 1.77250 49.6
6 5.08880 2.55380
7 * -16.51260 0.60000 1.54410 56.1
8 15.13410 0.11490
9 10.75730 0.95960 1.94595 18.0
10 33.23970 Variable
11 (Aperture 1) ∞ -0.08590
12 * 4.23020 1.67510 1.51776 69.9
13 * -14.19860 0.25000
14 (Aperture 2) ∞ 0.00000
15 5.26140 0.89530 1.70154 41.1
16 9.13560 0.01000 1.56732 42.8
17 9.13560 0.35000 1.84666 23.8
18 3.25590 Variable
19 * 21.65070 1.74000 1.54410 56.1
20 * -17.66480 variable
21 ∞ 0.80000 1.51680 64.2
22 ∞ 0.37000
23 ∞ (BF)
Image plane ∞

Table 8 (Aspherical data)

4th surface K = 0.00000E + 00, A4 = 1.69025E-05, A6 = 1.93134E-07, A8 = -1.17642E-08
A10 = 3.27810E-10, A12 = -4.48109E-12, A14 = 2.36404E-14, A16 = 0.00000E + 00
7th surface K = 0.00000E + 00, A4 = 4.61142E-04, A6 = -3.45253E-05, A8 = 2.34230E-06
A10 = -4.73645E-08, A12 = 0.00000E + 00, A14 = 0.00000E + 00, A16 = 0.00000E + 00
12th surface K = 0.00000E + 00, A4 = -1.15181E-03, A6 = 3.93138E-04, A8 = -1.67053E-04
A10 = 4.07248E-05, A12 = -2.82709E-06, A14 = -6.18533E-08, A16 = 0.00000E + 00
13th surface K = 0.00000E + 00, A4 = 1.13400E-03, A6 = 6.51554E-04, A8 = -2.72078E-04
A10 = 6.63743E-05, A12 = -4.88291E-06, A14 = -5.65986E-08, A16 = 2.37810E-12
19th surface K = 0.00000E + 00, A4 = 9.22737E-04, A6 = -5.75715E-05, A8 = 2.79486E-06
A10 = -4.21216E-08, A12 = 0.00000E + 00, A14 = 0.00000E + 00, A16 = 0.00000E + 00
20th surface K = 0.00000E + 00, A4 = 1.48827E-03, A6 = -1.65871E-04, A8 = 1.65675E-05
A10 = -1.21484E-06, A12 = 5.87659E-08, A14 = -1.53743E-09, A16 = 1.59274E-11

Table 9 (various data)

Zoom ratio 9.33019
Wide angle Medium telephoto Focal length 4.6197 14.1110 43.1029
F number 3.24493 5.08837 6.30160
Angle of View 41.2135 15.3419 5.1314
Image height 3.4500 3.9020 3.9020
Total lens length 34.3989 41.5046 48.4135
BF 0.43414 0.32845 0.37289
d4 0.3060 6.3831 13.7180
d10 11.6829 4.9579 0.3859
d18 3.5500 11.3731 16.4768
d20 4.0831 4.1192 3.1171
Entrance pupil position 9.6445 22.5852 56.8422
Exit pupil position -13.6977 -57.7278 807.5997
Front principal point position 12.7540 33.2665 102.2466
Rear principal point position 29.7792 27.3935 5.3106
Aperture 1 (diameter) 3.7760 3.7760 3.7760
Aperture 2 (diameter) 3.4400 3.4400 3.4400
* Aperture 1 is for the wide-angle end, and aperture 2 is for the middle and telephoto ends.

Single lens data Lens Start surface Focal length 1 1 -65.4255
2 3 19.1855
3 5 -6.2990
4 7 -14.4169
5 9 16.4715
6 12 6.4962
7 15 16.1465
8 17 -6.1427
9 19 18.1620

Zoom lens group data Group Start surface Focal length Lens construction length Front principal point position Rear principal point position 1 1 27.66189 3.81000 0.06360 1.50233
2 5 -5.87785 4.52830 0.27326 1.13244
3 11 9.07354 3.09450 -2.32889 -0.22903
4 19 18.16203 1.74000 0.63039 1.22567

Zoom lens group magnification group Start surface Wide angle Medium telephoto 1 1 0.00000 0.00000 0.00000
2 5 -0.31105 -0.45849 -1.07160
3 11 -0.79715 -1.64253 -1.99160
4 19 0.67355 0.67738 0.73011

(Numerical example 4)
The zoom lens system of Numerical Example 4 corresponds to Embodiment 4 shown in FIG. Table 10 shows surface data of the zoom lens system of Numerical Example 4, Table 11 shows aspheric data, and Table 12 shows various data.

Table 10 (surface data)

Surface number r d nd vd
Object ∞
1 15.33220 0.50000 1.92286 20.9
2 12.03590 0.01000 1.56732 42.8
3 12.03590 3.30000 1.58332 59.1
4 * -143.37120 Variable
5 -113.96490 0.30000 1.77250 49.6
6 5.08880 2.55380
7 * -16.51260 0.60000 1.54410 56.1
8 15.13410 0.11490
9 10.75730 0.95960 1.94595 18.0
10 33.23970 Variable
11 (Aperture 1) ∞ -0.08590
12 * 4.23020 1.67510 1.51776 69.9
13 * -14.19860 0.25000
14 (Aperture 2) ∞ 0.00000
15 5.26140 0.89530 1.70154 41.1
16 9.13560 0.01000 1.56732 42.8
17 9.13560 0.35000 1.84666 23.8
18 3.25590 Variable
19 * 21.65070 1.74000 1.54410 56.1
20 * -17.66480 variable
21 ∞ 0.80000 1.51680 64.2
22 ∞ 0.37000
23 ∞ (BF)
Image plane ∞

Table 11 (Aspheric data)

4th surface K = 0.00000E + 00, A4 = 1.69025E-05, A6 = 1.93134E-07, A8 = -1.17642E-08
A10 = 3.27810E-10, A12 = -4.48109E-12, A14 = 2.36404E-14, A16 = 0.00000E + 00
7th surface K = 0.00000E + 00, A4 = 4.61142E-04, A6 = -3.45253E-05, A8 = 2.34230E-06
A10 = -4.73645E-08, A12 = 0.00000E + 00, A14 = 0.00000E + 00, A16 = 0.00000E + 00
12th surface K = 0.00000E + 00, A4 = -1.15181E-03, A6 = 3.93138E-04, A8 = -1.67053E-04
A10 = 4.07248E-05, A12 = -2.82709E-06, A14 = -6.18533E-08, A16 = 0.00000E + 00
13th surface K = 0.00000E + 00, A4 = 1.13400E-03, A6 = 6.51554E-04, A8 = -2.72078E-04
A10 = 6.63743E-05, A12 = -4.88291E-06, A14 = -5.65986E-08, A16 = 2.37810E-12
19th surface K = 0.00000E + 00, A4 = 9.22737E-04, A6 = -5.75715E-05, A8 = 2.79486E-06
A10 = -4.21216E-08, A12 = 0.00000E + 00, A14 = 0.00000E + 00, A16 = 0.00000E + 00
20th surface K = 0.00000E + 00, A4 = 1.48827E-03, A6 = -1.65871E-04, A8 = 1.65675E-05
A10 = -1.21484E-06, A12 = 5.87659E-08, A14 = -1.53743E-09, A16 = 1.59274E-11

Table 12 (various data)

Zoom ratio 9.33019
Wide angle Medium telephoto Focal length 4.6197 14.1110 43.1029
F number 3.24493 5.00440 6.18468
Angle of View 41.2147 15.3422 5.1313
Image height 3.4500 3.9020 3.9020
Total lens length 34.3989 41.5046 48.4135
BF 0.43414 0.32845 0.37289
d4 0.3060 6.3831 13.7180
d10 11.6829 4.9579 0.3859
d18 3.5500 11.3731 16.4768
d20 4.0831 4.1192 3.1171
Entrance pupil position 9.6445 22.5852 56.8422
Exit pupil position -13.6977 -57.7278 807.5997
Front principal point position 12.7540 33.2665 102.2466
Rear principal point position 29.7792 27.3935 5.3106
Aperture 1 (diameter) 3.7760 3.7760 3.7760
Aperture 2 (diameter) 3.5100 3.5100 3.5100
* Aperture 1 is a wide-angle / intermediate aperture, and aperture 2 is a telephoto end.

Single lens data Lens Start surface Focal length 1 1 -65.4255
2 3 19.1855
3 5 -6.2990
4 7 -14.4169
5 9 16.4715
6 12 6.4962
7 15 16.1465
8 17 -6.1427
9 19 18.1620

Zoom lens group data Group Start surface Focal length Lens construction length Front principal point position Rear principal point position 1 1 27.66189 3.81000 0.06360 1.50233
2 5 -5.87785 4.52830 0.27326 1.13244
3 11 9.07354 3.09450 -2.32889 -0.22903
4 19 18.16203 1.74000 0.63039 1.22567

Zoom lens group magnification group Start surface Wide angle Medium telephoto 1 1 0.00000 0.00000 0.00000
2 5 -0.31105 -0.45849 -1.07160
3 11 -0.79715 -1.64253 -1.99160
4 19 0.67355 0.67738 0.73011

As described above, the embodiments have been described as examples of the technology in the present disclosure. For this purpose, the accompanying drawings and detailed description are provided.

Accordingly, among the components described in the accompanying drawings and the detailed description, not only the components essential for solving the problem, but also the components not essential for solving the problem in order to illustrate the above technique. May also be included. Therefore, it should not be immediately recognized that these non-essential components are essential as those non-essential components are described in the accompanying drawings and detailed description.

In addition, since the above-described embodiments are for illustrating the technique in the present disclosure, various modifications, replacements, additions, omissions, and the like can be made within the scope of the claims and the equivalents thereof.

The present disclosure can be applied to digital input devices such as digital cameras, cameras of portable information terminals such as smartphones, surveillance cameras in surveillance systems, Web cameras, and in-vehicle cameras. In particular, the present disclosure can be applied to a photographing optical system that requires high image quality, such as a digital camera.

G1 1st lens group G2 2nd lens group G3 3rd lens group G4 4th lens group L1 1st lens element L2 2nd lens element L3 3rd lens element L4 4th lens element L5 5th lens element L6 6th lens element L7 7th lens element L8 8th lens element L9 9th lens element A1 Aperture stop 1
A2 Aperture stop 2
P Parallel plate S Image plane 1 Zoom lens system 2 Image sensor 3 Liquid crystal monitor 4 Case 5 Main barrel 6 Moving barrel 7 Cylindrical cam

Claims

A zoom lens system having a plurality of lens groups each composed of at least one lens element,
With at least two aperture stops,
At least one lens element is disposed between the at least two aperture stops;
A zoom lens system, wherein, during zooming from the wide-angle end to the telephoto end during imaging, one of the at least two aperture stops is selected and the amount of light is adjusted according to the zoom position.
The zoom lens system according to claim 1, wherein an aperture stop selected at the wide angle end and an aperture stop selected at the telephoto end are different during zooming from the wide angle end to the telephoto end during imaging.
An imaging apparatus capable of outputting an optical image of an object as an electrical image signal,
A zoom lens system that forms an optical image of the object;
An image sensor that converts an optical image formed by the zoom lens system into an electrical image signal;
An imaging apparatus, wherein the zoom lens system is the zoom lens system according to claim 1.
A camera that converts an optical image of an object into an electrical image signal, and displays and stores the converted image signal;
An image pickup apparatus including a zoom lens system that forms an optical image of an object, and an image sensor that converts an optical image formed by the zoom lens system into an electrical image signal;
The camera according to claim 1, wherein the zoom lens system is the zoom lens system according to claim 1.