JP2014052413A - Zoom lens and image capturing device having the same - Google Patents

Abstract

PROBLEM TO BE SOLVED: To obtain a zoom lens having a wide angle of view, little occurrence of decentration aberrations even during image stabilization, easy high-speed focusing, and little aberration fluctuation during focusing.
[Solution]
In order from the object side to the image side, a first lens group having a negative refractive power, a second lens group having a positive refractive power, a third lens group having a negative refractive power, and a plurality of lens groups having a positive refractive power as a whole. A zoom lens having four or more lens groups that move during zooming, and the third lens group moves in a direction having a component in a direction perpendicular to the optical axis to shift the imaging position. A vibration-proof group that moves in a direction perpendicular to the axis, the rear group has a focus group, and the focal length fis of the third lens group and the focal length fR of the rear group at the telephoto end are respectively appropriate. Set to.
Satisfy the following conditional expression.
[Selection] Figure 1

Description

  The present invention relates to a zoom lens and is suitable for an imaging apparatus such as a digital camera, a video camera, a TV camera, a surveillance camera, and a silver salt film camera.

  An imaging optical system used in an imaging apparatus (camera) such as a video camera or a digital still camera is required to be a zoom lens having a wide angle of view and high optical performance over the entire zoom range. In addition, there is a need for a function that can perform focusing at high speed, and that has a function of suppressing image degradation due to image blurring caused by vibration such as camera shake during shooting in order to obtain a higher-definition image, a so-called anti-vibration function. Yes.

  2. Description of the Related Art Conventionally, a negative lead type zoom lens in which a lens group having a negative refractive power is positioned on the object side is known as a zoom lens that can easily widen the angle of view. In order to perform focusing at high speed, there is known a zoom lens using an inner focus method in which focusing is performed with a lens group that is smaller and lighter on the image side than the lens group on the most object side. A wide-angle zoom lens that is a negative lead type, uses an inner focus method, and has an anti-vibration function is known (Patent Documents 1 and 2).

  In Patent Document 1, the first to sixth lens units having negative, positive, negative, positive, negative, and positive refractive powers are sequentially arranged from the object side to the image side, and zooming is performed by changing each lens group interval. A zoom lens is disclosed. In Patent Document 1, image stabilization is performed with the fifth lens group, and focusing is performed with a part of the first lens group or the second lens group.

  Patent Document 2 discloses a four-group zoom lens that is composed of lens groups having negative, positive, negative, and positive refractive powers in order from the object side to the image side, and performs zooming by changing the distance between the lens groups. In Japanese Patent Laid-Open No. 2004-228688, some lens groups in the third lens group perform image stabilization, and focusing is performed in some lens groups in the second lens group. Non-Patent Document 1 discloses the aberration of an optical system having decentration.

JP 2004-061679 A JP 10-039210 A

By Matsuya Yoshiya Third-order aberration theory of optical system with eccentricity Japan Opto-Mechatronics Association 1989

  A negative lead type zoom lens preceded by a lens unit having a negative refractive power is characterized in that a wide angle of view is relatively easy. In the above-described four-group zoom lens, the first lens group and the second lens group as a whole constitute a lens group having a positive refractive power at the zoom position at the telephoto end, and the third lens group and the fourth lens group as a whole are negative. This constitutes a lens group having a refractive power of 2. The entire optical system is of a so-called telefort type and has a feature that the focal length at the telephoto end can be easily increased.

  In general, a negative lead type zoom lens is asymmetric in lens configuration with respect to the aperture stop, and therefore it is difficult to correct various aberrations. For example, decentration aberrations frequently occur during image stabilization, and aberration fluctuations during focusing increase, making it very difficult to obtain high optical performance.

  For example, in a negative lead type zoom lens, in order to perform high-speed focusing, in the inner focus type in which focusing is performed with a small and light lens group closer to the image side than the first lens group, there is a tendency that aberration fluctuations during focusing increase. is there. In order to achieve a wide angle of view in a negative lead type zoom lens with little occurrence of decentration aberrations during image stabilization and to perform high-speed focusing using the inner focus type, the refractive power of each lens group It is important to set the lens configuration appropriately.

  For example, if the lens group for anti-vibration and the focus group are appropriately set from multiple lens groups and the refractive power of these lens groups is not set appropriately, high optical performance can be obtained at the wide angle of view during vibration isolation and focusing. Will become difficult.

  SUMMARY OF THE INVENTION An object of the present invention is to provide a zoom lens that has a wide angle of view, generates less decentration aberrations even during image stabilization, is easy to perform high-speed focusing, and has less aberration fluctuations during focusing.

The zoom lens according to the present invention includes, in order from the object side to the image side, a first lens group having a negative refractive power, a second lens group having a positive refractive power, a third lens group having a negative refractive power, and a positive refraction as a whole. A zoom lens having a rear group including a plurality of lens groups of force, and four or more lens groups moving during zooming, wherein the third lens group is in a direction having a component perpendicular to the optical axis. A vibration-proof group that moves and moves the imaging position in a direction perpendicular to the optical axis, the rear group has a focus group, the focal length of the vibration-proof group of the third lens group is fis, and telephoto When the focal length of the rear group at the end is fR,
0.8 <| fR / fis | <1.3
It satisfies the following conditional expression.

  According to the present invention, it is possible to obtain a zoom lens that has a wide angle of view, generates less decentration aberrations even during image stabilization, is easy to perform high-speed focusing, and has less aberration fluctuations during focusing.

Cross-sectional view of a lens according to Example 1 of the present invention Aberration diagram in the reference state of Example 1 of the present invention Aberration diagram in the anti-vibration state when the optical axis is tilted by 0.3 ° in Example 1 of the present invention Lens sectional drawing of Example 2 of the present invention Aberration diagram in the reference state of Example 2 of the present invention Aberration diagram in the vibration proof state when the optical axis is inclined by 0.3 ° in Example 2 of the present invention Lens sectional view of Example 3 of the present invention Aberration diagram in the reference state of Example 3 of the present invention Aberration diagram in the image stabilization state when the optical axis is tilted by 0.3 ° in Example 3 of the present invention Lens sectional view of Example 4 of the present invention Aberration diagram in the reference state of Example 4 of the present invention Aberration diagram in the vibration proof state when the optical axis is inclined by 0.3 ° in Example 4 of the present invention Schematic diagram of main parts of an imaging apparatus of the present invention

  Embodiments of a zoom lens and an image pickup apparatus having the same according to the present invention will be described below with reference to the accompanying drawings. The zoom lens of the present invention includes, in order from the object side to the image side, a first lens group having a negative refractive power, a second lens group having a positive refractive power, a third lens group having a negative refractive power, and a plurality of lens groups. And a rear group of positive refractive power as a whole. The rear group includes, in order from the object side to the image side, a fourth lens group having a positive refractive power, a fifth lens group having a negative refractive power, and a sixth lens group having a positive refractive power. During zooming, four or more lens groups move.

  The third lens group includes an image stabilization group that has an image stabilization function that moves in a direction having a component perpendicular to the optical axis to move the imaging position in a direction perpendicular to the optical axis. At the time of focusing from an infinitely distant object to a close object, at least the fifth lens unit moves to the image side.

  In the zoom lens of the present invention, a lens group having refractive power such as a converter lens or an afocal lens group may be located on the object side of the first lens group and / or the image side of the final lens group.

  1A, 1B, and 1C are cross-sectional views of the zoom lens of Embodiment 1 of the present invention at the wide-angle end (short focal length end), the intermediate zoom position, and the telephoto end (long focal length end), respectively. FIG. FIGS. 2A, 2B, and 2C are aberration diagrams when the zoom lens of Example 1 of the present invention is focused on an object at infinity at the wide-angle end, the intermediate zoom position, and the telephoto end, respectively. 3A, 3B, and 3C focus on an object at infinity at the wide-angle end, the intermediate zoom position, and the telephoto end of the zoom lens according to Embodiment 1 of the present invention, respectively, and the optical axis is 0.3. FIG. 6 is a lateral aberration diagram when image blur is corrected (anti-vibration correction) when tilted.

  4A, 4B, and 4C are lens cross-sectional views at the wide-angle end, the intermediate zoom position, and the telephoto end, respectively, of the zoom lens according to the second exemplary embodiment of the present invention. FIGS. 5A, 5B, and 5C are aberration diagrams when the zoom lens of Example 2 of the present invention is focused on an object at infinity at the wide-angle end, the intermediate zoom position, and the telephoto end, respectively. FIGS. 6A, 6B, and 6C focus on an object at infinity at the wide-angle end, the intermediate zoom position, and the telephoto end of the zoom lens according to Embodiment 2 of the present invention, respectively, and the optical axis is 0.3. FIG. 6 is a lateral aberration diagram when image blur is corrected when tilted.

  FIGS. 7A, 7B, and 7C are lens cross-sectional views at the wide-angle end, the intermediate zoom position, and the telephoto end of the zoom lens according to Embodiment 3 of the present invention, respectively. 8A, 8B, and 8C are aberration diagrams when the zoom lens of Example 3 of the present invention is focused on an object at infinity at the wide-angle end, the intermediate zoom position, and the telephoto end, respectively. FIGS. 9A, 9B, and 9C focus on an object at infinity at the wide-angle end, the intermediate zoom position, and the telephoto end of the zoom lens according to Embodiment 3 of the present invention, respectively, and the optical axis is 0.3. FIG. 6 is a lateral aberration diagram when image blur is corrected when tilted.

  FIGS. 10A, 10B, and 10C are lens cross-sectional views at the wide-angle end, the intermediate zoom position, and the telephoto end, respectively, of the zoom lens according to the fourth exemplary embodiment of the present invention. FIGS. 11A, 11B, and 11C are aberration diagrams when the zoom lens of Example 4 of the present invention is focused on an object at infinity at the wide-angle end, the intermediate zoom position, and the telephoto end, respectively. FIGS. 12A, 12B, and 12C respectively focus on an object at infinity at the wide-angle end, the intermediate zoom position, and the telephoto end of the zoom lens according to Embodiment 4 of the present invention, and the optical axis is 0.3. FIG. 6 is a lateral aberration diagram when image blur is corrected when tilted. FIG. 13 is a schematic diagram of a main part of a single-lens reflex camera (imaging device) including the zoom lens of the present invention.

  The zoom lens of each embodiment is a photographing lens system (optical system) used in an imaging apparatus such as a video camera, a digital video camera, or a silver salt film camera. In the lens cross-sectional view, the left side is the object side (front), and the right side is the image side (rear). In the lens cross-sectional view, i indicates the order of the lens groups from the object side, and Li is the i-th lens group. SP is an aperture stop. SSP is an F-number aperture (Fno aperture). The F number diaphragm SSP adjusts the value of the F number at each zoom position by changing the aperture diameter during zooming.

  IP is an image plane, and when used as a photographing optical system for a video camera or a digital still camera, on the imaging surface of a solid-state imaging device (photoelectric conversion device) such as a CCD sensor or a CMOS sensor, Corresponds to the film surface. The arrows indicate the movement trajectory of each lens unit during zooming from the wide-angle end to the telephoto end.

  The spherical aberration diagram shows the d-line. In the astigmatism diagram, M and S are a meridional image surface and a sagittal image surface at the d-line. Fno is the F number, and ω is the half angle of view. In the lateral aberration diagram, Y is the image height. In each of the following embodiments, the wide-angle end and the telephoto end refer to zoom positions when the zoom lens unit is positioned at both ends of a range in which the zoom lens group can move on the optical axis.

  The zoom lens according to each exemplary embodiment sequentially (continuously) from the object side to the image side, the first lens unit L1 having a negative refractive power, the second lens unit L2 having a positive refractive power, and the third lens unit having a negative refractive power. The lens unit L3 includes a plurality of lens units, and has a rear unit LR having a positive refractive power as a whole. Four or more lens groups move during zooming. The third lens unit L3 has an image stabilizing group that moves in a direction having a component perpendicular to the optical axis and moves the imaging position in a direction perpendicular to the optical axis.

  In Examples 1, 2, and 4, image stabilization is performed by all of the third lens unit L3, and in Example 3, some lens units of the third lens unit L3. The rear group LR has a focus group. The rear group LR includes a fourth lens unit L4 having a positive refractive power, a fifth lens unit L5 having a negative refractive power, and a sixth lens unit L6 having a positive refractive power in order from the object side to the image side. The fifth lens unit L5 moves.

  A second focus group (floating lens group Lflo) that moves in the optical axis direction during focusing is provided on the object side of the focus group. The anti-vibration group includes one lens having a positive refractive power and one lens having a negative refractive power. The third lens unit L3 includes at least one aspheric surface.

  Next, the image stabilization function according to the zoom lens of the present invention will be described. In general, a condition necessary for reducing the eccentric field curvature in the vibration-proof state is expressed by the following equation.

_{α 'p · P q -α p} (P p + P q) = 0 ··· (A) formula (A) P _p is the Petzval sum of the image-stabilizing group in the formula, P _q is on the image side of the vibration-proof group The Petzval sum of the rear group, α _p represents the angle of light incident on the image stabilization group, and α ′ _p represents the angle of light emitted from the image stabilization group. From equation (A), in order to make the field curvature in the eccentric state zero, for example, in this equation (A), the following condition is required.

Α ′ _p = 0, that is, the light beam emitted from the image stabilizing group is parallel to the optical axis (afocal). The combined Petzval sum of the image stabilizing lens group and the lens group on the image side from the image stabilizing group is 0. It is necessary to be.

  While maintaining the performance of the reference state and the performance of the vibration proof function, approaching the above formula (A) leads to the improvement of the vibration proof performance. The Petzval sum is represented by a relational expression between the refractive power of the lens (or lens group) and the refractive index of the material. That is, if the ratio of the refractive powers of the image stabilizing group and the lens group on the image side of the image stabilizing group is close to 1, the above formula (A) is satisfied, which leads to an improvement in field curvature at the time of decentering.

In the negative lead type 6-group zoom lens having a large aperture ratio including a wide-angle region, the present inventor has a third lens group having a negative refractive power and a refractive power of a rear group located closer to the image side than the third lens group. Set appropriately. As a result, the inventors have found a condition that can favorably correct the decentered field curvature. Based on this, the present invention is characterized by the following configuration. The focal length of the anti-vibration group of the third lens unit L3 is fis, and the focal length of the rear group LR at the telephoto end is fR. At this time,
0.8 <| fR / fis | <1.3 (1)
The following conditional expression is satisfied.

  Conditional expression (1) is mainly for favorably correcting the decentered field curvature with respect to the anti-vibration group of the third lens unit L3 and the refractive power of the rear unit LR at the telephoto end. If the ratio of the refractive powers of the image stabilizing group and the rear group LR exceeds the upper limit value or the lower limit value of the conditional expression (1), the direction deviates from the condition of the decentered field curvature described above. It becomes difficult to obtain good optical performance.

  Furthermore, if the refractive power of the vibration isolation group exceeds the upper limit of conditional expression (1), it becomes difficult to correct the variation of spherical aberration due to zooming, and the optical performance at the center of the screen in the vibration isolation state deteriorates. . If the refractive power of the vibration isolation group becomes weaker than the lower limit of conditional expression (1), downsizing becomes difficult. Further, by providing a focus group in the rear group LR where the height of the light beam from the optical axis is low, it is less susceptible to spherical aberration due to focus, and the optical performance in the entire focus area is improved.

In the present invention, the following conditional expression is more preferably satisfied. The focal length of the focus group in the rear group LR is fr, and the focal length of the entire system at the wide angle end is fw. At this time,
1.8 <| fr / fw | <3.0 (2)
It is good to satisfy the following conditional expression.

  Conditional expression (2) relates to the refractive power of the focus group. If the upper limit of conditional expression (2) is exceeded and the refractive power of the focus group becomes weak, the amount of movement of the focus group becomes large during focusing, and the entire system becomes large. If the lower limit of conditional expression (2) is exceeded and the refracting power of the focus group becomes strong, image plane fluctuations will increase during zooming, making it difficult to correct this aberration well. Conditional expressions (1) and (2) are more desirably within the following numerical ranges.

1.00 <| fR / fis | <1.25 (1a)
2.0 <| fr / fw | <2.5 (2a)
Below, each Example of this invention is described.

  In Example 1 of FIG. 1, the first lens unit L1 moves to the image side during zooming from the wide-angle end to the telephoto end. The second lens unit L2 moves to the object side. The third lens unit L3 moves along a locus convex to the object side integrally with the stop SP and the F-number stop (Fno stop) SP2 (the same movement locus). The fourth lens unit L4 moves to the object side. The fifth lens unit L5 moves to the object side. The sixth lens unit L6 is stationary.

  During zooming from the wide-angle end to the telephoto end, the first lens unit L1, the second lens unit L2, the fourth lens unit L4, and the fifth lens unit L5 perform zooming and an image plane that moves by zooming (image plane variation) ) Is corrected by the movement of the third lens unit L3. By moving the five lens groups during zooming, a necessary zoom ratio is obtained, and variations in various aberrations due to zooming are suppressed. The fifth lens unit L5 is a focus unit, and performs focusing from an infinitely distant object to a very close object by moving to the image side.

  Further, when focusing from an infinite object to a close object, the first and second partial lens groups (second focus group) Lflo from the object side in the fourth lens unit L4 are independent of the fifth lens unit L5. (With different trajectories). That is, floating is used. As a result, aberration fluctuations during focusing are corrected. In addition, the entire third lens unit L3 is moved in a direction having a component perpendicular to the optical axis, and the image blur is corrected when the zoom lens vibrates by moving the imaging position. That is, vibration isolation is performed.

  In the first embodiment, the conditional expressions (1) and (2) are more preferably in the following numerical ranges.

1.0 <| fR / fis | ≦ 1.2
2.0 <| fr / fw | <2.3
In Example 1, the first lens unit L1 has two aspheric surfaces. As a result, the meridional image plane that is insufficiently corrected when the sagittal curvature of the image around the screen is corrected at the wide-angle end, and distortion are satisfactorily corrected.

  In Example 1, one aspheric surface is provided for each of the fifth lens unit L5 and the sixth lens unit L6. As a result, the field curvature at the wide-angle end and the distortion at the telephoto end are corrected well.

  In Example 2 of FIG. 4, the first lens unit L1 moves to the image side during zooming from the wide-angle end to the telephoto end. The second lens unit L2 moves to the object side. The third lens unit L3 does not move. The fourth lens unit L4 moves to the object side. The fifth lens unit L5 moves to the object side. The sixth lens unit L6 is stationary.

  During zooming from the wide-angle end to the telephoto end, the second lens unit L2, the fourth lens unit L4, and the fifth lens unit L5 move to perform zooming, and the image plane that moves by zooming is changed to the first lens unit L1. It is corrected by moving. By moving the four lens groups during zooming, a necessary zoom ratio is obtained and fluctuations in various aberrations due to zooming are suppressed.

  Further, by moving the fifth lens unit L5 to the image side, focusing from an object at infinity to an object at a close distance is performed. Further, during focusing from an object at infinity to a close object, the lens unit Lflo including the second and third lenses from the object side of the third lens unit L3 and the aperture stop SP moves independently of the fifth lens unit L5. Is used. As a result, aberration fluctuations during focusing are corrected. In addition, the entire third lens unit L3 is shaken.

  In the second embodiment, the conditional expressions (1) and (2) necessary for obtaining higher performance and the meaning thereof are the same as those in the numerical embodiment 1. More preferably, each of the conditional expressions (1) and (2) is within the following numerical ranges. It is desirable to be.

1.0 <| fR / fis | <1.2
2.2 <| fr / fw | <2.5
In Example 2, the first lens unit L1 has two aspheric surfaces. As a result, the meridional image plane that is insufficiently corrected when the sagittal curvature of the image around the screen is corrected at the wide-angle end, and distortion are satisfactorily corrected. In Example 2, the third lens unit L3 is provided with one aspherical surface, and spherical aberration is corrected well at the telephoto end. In Example 2, one aspheric surface is provided for each of the fifth lens unit L5 and the sixth lens unit L6. As a result, the field curvature is corrected at the wide-angle end, and the distortion is corrected at the telephoto end.

  Example 3 in FIG. 7 is the same zoom type as Example 2 in FIG. In Example 3, the fifth lens unit L5 is moved to the image side to focus from an object at infinity to an object at a close range. Further, when focusing from an object at infinity to a close object, the fifth lens unit L5 includes a lens unit Lflo including the second and third lenses, the stop SP, and the fourth lens from the object side of the third lens unit L3. It uses floating that moves independently. As a result, aberration fluctuations during focusing are corrected.

  The third lens group L3 is divided into a third-a lens group L3a and a third-b lens group L3b in order from the object side to the image side. The third-a lens unit L3a performs image stabilization. In Example 3, the conditional expressions (1) and (2) and their meanings necessary for obtaining higher performance are the same as those in Numerical Example 1, but more desirably, in the following numerical ranges, respectively. It is desirable to be.

1.0 <| fR / fis | <1.2
2.2 <| fr / fw | <2.5
In Example 3, the first lens unit L1 has two aspheric surfaces. As a result, the meridional image plane that is insufficiently corrected when the sagittal curvature of the image around the screen is corrected at the wide-angle end, and distortion are satisfactorily corrected. In Example 3, one aspheric surface is provided in the third lens unit L3. Thereby, spherical aberration is corrected at the telephoto end. In Example 3, one aspherical surface is provided for each of the fifth lens unit L5 and the sixth lens unit L6. As a result, the field curvature is corrected at the wide-angle end, and the distortion is corrected at the telephoto end.

  Example 4 in FIG. 10 is the same zoom type as Example 1 in FIG. In Example 4, the fifth lens unit L5 is moved to the image side to focus from an object at infinity to an object at close range. In addition, the entire third lens unit L3 is shaken.

  In Example 4, the conditional expressions (1) and (2) and their meanings necessary for obtaining higher performance are the same as those in Example 1, but more preferably within the following numerical ranges. It is desirable.

1.0 <| fR / fis | <1.3
2.0 <| fr / fw | <2.2
In Example 4, the first lens unit L1 has two aspheric surfaces. As a result, the meridional image plane that is insufficiently corrected when the sagittal curvature of the image around the screen is corrected at the wide-angle end, and distortion are satisfactorily corrected. In Example 4, one aspherical surface is provided for each of the fifth lens unit L5 and the sixth lens unit L6. As a result, the field curvature is corrected at the wide-angle end, and the distortion is corrected at the telephoto end.

  Next, an embodiment in which the zoom lens shown in Embodiments 1 to 4 is applied to an imaging apparatus will be described with reference to FIG. FIG. 13 is a schematic view of the main part of a single-lens reflex camera. In FIG. 13, reference numeral 10 denotes a photographing lens having the zoom lens 1 according to the first to fourth embodiments. The zoom lens 1 is held by a lens barrel 2 that is a holding member. Reference numeral 20 denotes a camera body, which includes a quick return mirror 3 that reflects the light beam from the photographing lens 10 upward, and a focusing screen 4 that is disposed at an image forming position of the photographing lens 10. Further, it is constituted by a penta roof prism 5 for converting an inverted image formed on the focusing screen 4 into an erect image, an eyepiece 6 for observing the erect image, and the like.

  Reference numeral 7 denotes a photosensitive surface, on which a solid-state imaging device (photoelectric conversion device) or a silver salt film that receives an image formed by a zoom lens such as a CCD sensor or a CMOS sensor is arranged. At the time of photographing, the quick return mirror 3 is retracted from the optical path, and an image is formed on the photosensitive surface 7 by the photographing lens 10.

  The zoom lens of the present invention can be similarly applied to a so-called mirrorless camera having no quick return mirror.

  Numerical examples 1 to 4 corresponding to the examples 1 to 4 are shown below. In each numerical example, i indicates the order of the surfaces from the object side. In numerical examples, ri is the radius of curvature of the i-th lens surface in order from the object side, di is the i-th lens thickness and air spacing in order from the object side, and ndi and νdi are the i-th lens in order from the object side. The refractive index and Abbe number of the material. BF is a back focus. The aspherical shape is the X axis in the optical axis direction, the H axis in the direction perpendicular to the optical axis, the light traveling direction is positive, r is the paraxial radius of curvature, k is the conic constant, and each aspheric coefficient is A4, A6, A8. , A10, A12,

Shall be given in “E ± xx” in each aspherical coefficient means “× 10 ^{± xx} ”. Table 1 shows the relationship between the above-described conditional expressions and numerical examples.

Numerical example 1
Unit mm

Surface data
Surface number rd nd νd Effective diameter
1 * 196.2 2.5 1.81600 46.6 64.2
2 37.108 15.77 52.79
3 -87.808 3 1.67790 55.3 52.28
4 193.218 0.1 51.36
5 150.601 5 1.84666 23.9 51.36
6 * -535.09 (variable) 51.02
7 364.3 4 1.59282 68.6 39.01
8 -202.896 0.5 39.17
9 92.548 1.5 1.84666 23.8 39.14
10 47.931 7 1.59282 68.6 38.44
11 -156.671 0.15 38.26
12 54.198 4.44 1.88300 40.8 37.85
13 332.084 (variable) 37.39
14 (Fno aperture) ∞ 2.2 26.95
15 -182.294 1.3 1.85026 32.3 26.16
16 66.941 2.81 25.64
17 -53.616 1.3 1.70154 41.2 25.64
18 34.437 5 1.80518 25.4 26.8
19 -71.646 0.7 26.94
20 (Aperture) ∞ (Variable) 26.85
21 -1885.026 1.8 1.76182 26.5 26.74
22 27.152 5 1.49700 81.5 26.63
23 -111.905 0.5 26.76
24 78.076 3.65 1.75 500 52.3 27.13
25 -3545.744 0.1 26.97
26 53.21 4.29 1.54072 47.2 26.74
27 -100.41 (variable) 26.3
28 -824.848 4 1.80809 22.8 24.98
29 -31.396 1.5 1.68893 31.1 25.08
30 * 32.335 (variable) 25.15
31 54.443 5 1.49700 81.5 35.94
32 -243.747 1.8 1.56732 42.8 36.14
33 * -1009.292 38.31 36.46
Image plane ∞

Aspheric data
First side
K = 0 A 4 = 1.6576E-06 A 6 = -1.7906E-10 A 8 = -7.5648E-13
A10 = 8.3288E-16 A12 = -2.8004E-19
6th page
K = 0 A 4 = 2.6536E-07 A 6 = -2.1869E-10 A 8 = -1.0520E-12
A10 = 2.0002E-15 A12 = -1.1706E-18
30th page
K = 0 A 4 = 2.6901E-06 A 6 = 6.0073E-10 A 8 = -4.3855E-11
A10 = 4.0316E-13 A12 = -1.2298E-15
Side 33
K = 0 A 4 = -1.0168E-06 A 6 = -4.9484E-10 A 8 = -6.4460E-12
A10 = 1.9436E-14 A12 = -1.6566E-17

Various data
Zoom ratio 2.75

Focal length 24.7 35.21 68
F number 2.9 2.9 2.9
Angle of view 41.21 31.57 17.65
Image height 21.64 21.64 21.64
Total lens length 223.94 207.87 180.56
BF 38.31 38.31 38.31

d6 70.28 43.64 3.92
d13 2.06 6.64 23.43
d20 22.1 16.61 2.38
d27 1.61 1.26 8.62
d30 4.67 16.5 19

Entrance pupil position 36.32 35.46 45.15
Exit pupil position -64.58 -81.07 -61.31
Front principal point position 55.1 60.29 66.73
Rear principal point position 13.6 3.1 -29.69

Numerical example 2
Unit mm

Surface data
Surface number rd nd νd Effective diameter
1 * 362.69 2.5 1.83481 42.7 65.36
2 39.575 14.9 54.11
3 -110.274 3 1.81600 46.6 53.6
4 360.181 0.1 53.12
5 147.49 5 1.80809 22.8 53.12
6 * -431.199 (variable) 52.82
7 190.423 4 1.59282 68.6 40.73
8 -185.424 0.5 40.76
9 111.553 1.5 1.84666 23.8 40.42
10 57.057 6.75 1.59282 68.6 39.7
11 -152.806 0.15 39.43
12 52.595 4.16 1.88300 40.8 37.52
13 161.033 (variable) 36.55
14 (Fno aperture) ∞ 2.2 26.56
15 * 2587.899 1.3 1.85026 32.3 25.63
16 50.533 4.75 24.99
17 -37.055 1.3 1.65 160 58.5 25
18 39.377 4.2 1.80518 25.4 26.66
19 -76.303 0.7 26.8
20 (Aperture) ∞ (Variable) 26.92
21 73.606 5.83 1.72047 34.7 27.16
22 -42.075 1.8 1.84666 23.9 26.89
23 28.245 7.25 1.49700 81.5 26.43
24 -49.491 0.1 26.8
25 40.357 4.29 1.72342 38 26.78
26 -265.361 (variable) 26.79
27 252.791 3.59 1.80809 22.8 26.38
28 -31.346 1.2 1.68893 31.1 26.35
29 * 28.767 (variable) 25.25
30 62.841 4.44 1.51742 52.4 34.33
31 -756.344 1.8 1.81600 46.6 34.55
32 * 284.297 38.45 34.81
Image plane ∞

Aspheric data
First side
K = 0 A 4 = 1.8101E-06 A 6 = -5.2601E-10 A 8 = -3.9127E-13
A10 = 6.0823E-16 A12 = -2.2293E-19
6th page
K = 0 A 4 = 3.4793E-07 A 6 = 4.3814E-11 A 8 = -1.6229E-12
A10 = 2.4321E-15 A12 = -1.2420E-18
15th page
K = 0 A 4 = -2.3540E-08 A 6 = -3.6445E-10 A 8 = -1.3268E-12
A10 = 5.1001E-15 A12 = 2.3657E-17
29th page
K = 0 A 4 = 3.9673E-06 A 6 = 7.8750E-09 A 8 = -6.0753E-11
A10 = 2.9342E-13 A12 = -5.0706E-16
32nd page
K = 0 A 4 = -1.2476E-06 A 6 = -4.4446E-09 A 8 = 1.4244E-11
A10 = -4.5223E-14 A12 = 6.5128E-17

Various data
Zoom ratio 2.74

Focal length 24.8 35.46 67.88
F number 2.9 2.9 2.9
Angle of View 41.1 31.39 17.68
Image height 21.64 21.64 21.64
Total lens length 222.12 200.09 179.64
BF 38.45 38.45 38.45

d6 67.47 39.56 3.52
d13 2.06 7.94 23.53
d20 19.38 14.18 2.29
d26 1.9 1.43 6.12
d29 5.55 11.23 18.43

Entrance pupil position 36.29 35.93 46.27
Exit pupil position -58.64 -55.44 -48.57
Front principal point position 54.76 58 61.2
Rear principal point position 13.65 2.99 -29.43

Numerical Example 3
Unit mm

Surface data
Surface number rd nd νd Effective diameter
1 * 345.302 2.5 1.83481 42.7 65.28
2 38.993 15.28 53.89
3 -110.712 3 1.81600 46.6 53.2
4 387.696 0.1 52.73
5 148.923 5 1.80809 22.8 52.71
6 * -465.464 (variable) 52.39
7 187.748 4 1.59282 68.6 40.4
8 -192.748 0.5 40.43
9 112.882 1.5 1.84666 23.8 40.12
10 57.321 6.68 1.59282 68.6 39.43
11 -150.442 0.15 39.18
12 51.852 4.15 1.88300 40.8 37.31
13 159.241 (variable) 36.35
14 (Fno aperture) ∞ 2.2 26.99
15 * 565.596 1.3 1.85026 32.3 25.99
16 50.457 4.87 25.31
17 -36.601 1.3 1.65160 58.5 25.29
18 42.032 4.54 1.80518 25.4 26.85
19 -72.011 0.7 27.05
20 (Aperture) ∞ 0.51 27.11
21 -500 1.5 1.65 160 58.5 27.13
22 -9130.85 (variable) 27.19
23 76.049 5.83 1.72047 34.7 27.3
24 -42.872 1.8 1.84666 23.9 27.02
25 28.656 6.77 1.49700 81.5 26.58
26 -48.331 0.1 26.86
27 40.318 4.29 1.72342 38 26.76
28 -290.909 (variable) 26.25
29 262.709 3.43 1.80809 22.8 25.92
30 -31.689 1.2 1.68893 31.1 25.89
31 * 29.05 (variable) 24.93
32 64.115 4.44 1.51742 52.4 33.79
33 -191.243 1.8 1.81600 46.6 33.98
34 * 469.952 38.45 34.35
Image plane ∞

Aspheric data
First side
K = 0 A 4 = 1.82695E-06 A 6 = -5.59826E-10 A 8 = -3.60185E-13
A10 = 6.06446E-16 A12 = -2.21010E-19
6th page
K = 0 A 4 = 3.61845E-07 A 6 = 5.85680E-11 A 8 = -1.72273E-12
A10 = 2.44714E-15 A12 = -1.11301E-18
15th page
K = 0 A 4 = 1.97376E-07 A 6 = -3.80131E-10 A 8 = -5.00794E-12
A10 = 2.14044E-14 A12 = 2.17990E-17
No. 31
K = 0 A 4 = 4.11460E-06 A 6 = 8.17932E-09 A 8 = -5.99184E-11
A10 = 2.92751E-13 A12 = -5.60420E-16
34th page
K = 0 A 4 = -1.44710E-06 A 6 = -4.68443E-09 A 8 = 1.41827E-11
A10 = -4.22006E-14 A12 = 5.95456E-17

Various data
Zoom ratio 2.73

Focal length 24.86 35.19 67.87
F number 2.9 2.9 2.9
Angle of View 41.03 31.58 17.68
Image height 21.64 21.64 21.64
Total lens length 222.18 200.75 179.07
BF 38.45 38.45 38.45

d6 67.59 40.52 3.5
d13 2.06 7.7 23.05
d22 17.39 12.19 0.3
d28 1.9 1.33 6.46
d31 5.34 11.11 17.87

Entrance pupil position 36.19 35.86 45.8
Exit pupil position -55.56 -52.88 -46.46
Front principal point position 54.47 57.49 59.42
Rear principal point position 13.59 3.26 29.43

Numerical Example 4
Unit mm

Surface data
Surface number rd nd νd Effective diameter
1 * 683.387 2.5 1.69680 55.5 67.2
2 35.736 16.16 53.26
3 -95.283 3 1.69700 48.5 52.94
4 227.091 0.1 52.06
5 180.628 5 1.84666 23.9 52.05
6 * -693.867 (variable) 51.69
7 207.908 4 1.59282 68.6 41.14
8 -189.06 0.5 41.27
9 97.281 1.5 1.84666 23.8 41.2
10 44.305 7 1.59282 68.6 40.34
11 -137.056 0.15 40.29
12 54.672 4.44 1.88300 40.8 38.67
13 325.488 (variable) 37.92
14 (Fno aperture) ∞ 2.2 26.15
15 -155.659 1.3 1.83400 37.2 25.4
16 68.417 3 24.92
17 -47.869 1.3 1.72000 43.7 24.93
18 31.611 5 1.80518 25.4 26.27
19 -73.205 0.7 26.43
20 (Aperture) ∞ (Variable) 26.47
21 1261.153 1.8 1.85026 32.3 26.52
22 29.049 5 1.49700 81.5 26.52
23 -82.058 0.5 26.7
24 74.332 3.65 1.75 500 52.3 27.32
25 -8952.075 0.1 27.23
26 53.149 4.29 1.49700 81.5 27.09
27 -65.982 (variable) 26.84
28 28854.334 4 1.80809 22.8 25.23
29 -31.585 1.5 1.72151 29.2 25.25
30 * 31.008 39.96 25.04
31 49.492 6 1.49700 81.5 38.35
32 -203.948 1.8 1.65160 58.5 38.51
33 * -311.601 39.96 38.77
Image plane ∞

Aspheric data
First side
K = 0 A 4 = 2.52853E-06 A 6 = -9.26695E-10 A 8 = -5.49944E-13
A10 = 7.82065E-16 A12 = -2.59519E-19
6th page
K = 0 A 4 = 1.61298E-07 A 6 = -3.26146E-10 A 8 = -1.47280E-12
A10 = 1.97891E-15 A12 = -8.92676E-19
30th page
K = 0 A 4 = 1.85730E-06 A 6 = -5.97366E-09 A 8 = 2.39496E-11
A10 = 1.04595E-13 A12 = -7.58148E-16
Side 33
K = 0 A 4 = -2.92686E-07 A 6 = -7.05282E-10 A 8 = -4.37424E-12
A10 = 1.68920E-14 A12 = -1.68449E-17

Various data
Zoom ratio 2.95

Focal length 22.98 33.55 67.9
F number 2.9 2.9 2.9
Angle of view 43.27 32.82 17.67
Image height 21.64 21.64 21.64
Total lens length 221.92 206.85 183.76
BF 39.96 39.96 39.96

d6 68.17 40.46 2.54
d13 2.06 6.58 25.16
d20 19.61 15.35 2.16
d27 1.61 2.1 9.16
d30 4.01 15.91 18.29

Entrance pupil position 35.02 34.23 46.42
Exit pupil position -63.94 -88.98 -66.62
Front principal point position 52.92 59.05 71.07
Rear principal point position 16.98 6.41 -27.94

L1 1st lens group L2 2nd lens group L3 3rd lens group L4 4th lens group L5 5th lens group L6 6th lens group SP Aperture

Claims (9)

In order from the object side to the image side, a first lens group having a negative refractive power, a second lens group having a positive refractive power, a third lens group having a negative refractive power, and a plurality of lens groups having a positive refractive power as a whole. A zoom lens having four or more lens groups that move during zooming, wherein the third lens group moves in a direction having a component in a direction perpendicular to the optical axis to change the imaging position. It has a vibration isolation group that moves in the direction perpendicular to the optical axis,
When the rear group has a focus group, the focal length of the image stabilizing group of the third lens group is fis, and the focal length of the rear group at the telephoto end is fR,
0.8 <| fR / fis | <1.3
A zoom lens satisfying the following conditional expression: When the focal length of the focus group of the rear group is fr and the focal length of the entire system at the wide angle end is fw,
1.8 <| fr / fw | <3.0
The zoom lens according to claim 1, wherein the following conditional expression is satisfied.   3. The zoom lens according to claim 1, further comprising a second focus group that moves in an optical axis direction during focusing on the object side of the focus group.   4. The zoom lens according to claim 1, wherein the anti-vibration group includes one lens having a positive refractive power and one lens having a negative refractive power. 5.   The rear group includes, in order from the object side to the image side, a fourth lens group having a positive refractive power, a fifth lens group having a negative refractive power, and a sixth lens group having a positive refractive power. The zoom lens according to claim 1, wherein the five lens groups move.   The zoom lens according to claim 1, wherein the third lens group includes at least one aspheric surface.   The rear group includes, in order from the object side to the image side, a fourth lens group having a positive refractive power, a fifth lens group having a negative refractive power, and a sixth lens group having a positive refractive power. The first lens group moves to the image side during zooming toward the end, and the second lens group, the fourth lens group, and the fifth lens group move to the object side. 6. The zoom lens according to any one of 6 above. The rear group includes, in order from the object side to the image side, a fourth lens group having a positive refractive power, a fifth lens group having a negative refractive power, and a sixth lens group having a positive refractive power. During zooming to the end, the first lens group moves toward the image side, the second lens group, the fourth lens group, and the fifth lens group move toward the object side, and the third lens group moves toward the object side. 7. The zoom lens according to claim 1, wherein the zoom lens moves along a convex locus.   An image pickup apparatus comprising: the zoom lens according to claim 1; and a photoelectric conversion element that receives an image formed by the zoom lens.