JP2008304857A - Zoom lens system and camera system - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a zoom lens system which has a maximum half angle of around 3.3° at its telephoto end, makes high-speed automatic focusing possible, has an image blurring-correcting function, has excellent imaging characteristics and is compact in size; and to provide a camera using the zoom lens system. <P>SOLUTION: The zoom lens system has, sequentially from an object side, the first lens group having positive power, the second lens group having negative power, the third lens group having positive power, the fourth lens group having negative power, the fifth lens group having positive power and the sixth lens group having negative power. The fifth lens group has, sequentially from the object side, the fifth-a lens group and the fifth-b lens group arranged through the fifth-a lens group and an air interval which does not change at the time of zooming. The zoom lens system changes, at the time of zooming, an interval between the first and second lens groups and an interval between the third and fourth lens groups so that the air intervals between the first and second lens groups and the air interval between the third and fourth lens groups may be longer at the telephoto end than at the wide-angle end. The zoom lens system moves, at the time of focusing, the sixth lens group along the optical axis, and also parallely moves the fifth-b lens group in the direction perpendicular to the optical axis when the image blurring caused by the oscillation of the whole system is corrected. <P>COPYRIGHT: (C)2009,JPO&INPIT

Description

  The present invention relates to a zoom lens system and a camera system, and more particularly to a zoom lens system suitable as an imaging optical system used in an interchangeable lens apparatus of a so-called digital single lens reflex camera system, and a camera system including the interchangeable lens apparatus.

  A camera body having an imaging element such as a CCD (Charge Coupled Device), CMOS (Complementary Metal-Oxide Semiconductor), and an interchangeable lens apparatus having an imaging optical system for forming an optical image on the light receiving surface of the imaging element The market for digital single-lens reflex camera systems in which the imaging lens system is detachable from the camera body is rapidly expanding. Such an interchangeable lens device is popularly equipped with a zoom lens system capable of forming an optical image so as to be variable in magnification.

  Among zoom lens systems, in particular, the telephoto zoom lens system has a long focal length at the telephoto end, and therefore the total optical length (the distance from the apex of the lens surface closest to the object side to the image plane) tends to be long. Therefore, a configuration in which the optical total length at the telephoto end is shorter than the focal length at the telephoto end by arranging the lens group with the positive power closest to the object side and the lens group with the negative power closest to the image side. There are many.

  In a telephoto zoom lens system, a configuration in which the number of lens groups is increased in order to reduce various aberrations has been proposed. For example, there is a configuration using six positive, negative, positive, positive, and negative lens groups (for example, Patent Documents). 1). In the telephoto zoom lens system, the focal length at the telephoto end is long, and thus image blur due to vibration is likely to occur. In view of this, a method has been proposed in which some lens groups are translated in a direction perpendicular to the optical axis in accordance with the posture change of the entire lens system (for example, Patent Documents 2, 3, and 4). The telephoto zoom lens system disclosed in Patent Literatures 2, 3, and 4 is composed of six lens groups that are positive, negative, positive, negative, positive and negative in order from the object side, and the second lens group positioned second from the object side is the optical axis. Image blur correction is performed by translating in the vertical direction.

Furthermore, the zoom lens system disclosed in Patent Document 2 aims to improve the imaging characteristics at the time of close-up shooting, and performs focusing by moving the two lens groups of the fourth lens group and the sixth lens group. Like to do.
Japanese Patent No. 3313879 JP 2000-47107 A Japanese Patent Laid-Open No. 2007-3600 Japanese Patent No. 3706644

  The focusing of the telephoto zoom lens is generally performed by moving the first group closest to the object side. The focusing method based on the movement of the first group has a problem that high-speed autofocus cannot be performed because the first lens group is large and heavy.

  However, the zoom lens systems of Patent Documents 1, 3, and 4 do not mention focusing at all. In the zoom lens system of Patent Document 2, focusing is performed by moving the two lens groups of the fourth lens group and the sixth lens group, so that the configuration of the lens barrel is inevitable, and high-speed autofocusing is inevitable. Is difficult to do.

  In addition, the zoom lens system of Patent Document 1 makes no mention of image blur correction. In the telephoto zoom lenses disclosed in Patent Documents 2, 3, and 4, image blur correction is performed by parallel movement in a direction perpendicular to the optical axis of the second lens group. However, the second lens group includes three lenses. The weight is heavy. For this reason, there is a problem that the actuator for moving the second lens group in parallel increases, and the outer diameter of the lens barrel increases.

  The present invention is a compact zoom lens system having a maximum half angle of view at the telephoto end of about 3.3 °, capable of high-speed autofocus, equipped with an image blur correction function, good imaging characteristics, and zooming thereof. An object is to provide a camera system using a lens system.

  One of the above objects is achieved by the following zoom lens system. That is, the zoom lens system of the present invention includes, in order from the object side to the image side, a first lens group having a positive power, a second lens group having a negative power, and a third lens group having a positive power. A fourth lens group having a negative power; a fifth lens group having a positive power; and a sixth lens group having a negative power; the fifth lens group includes a 5a lens group from the object side; The 5a lens group and a 5b lens group disposed through an air gap that does not change during zooming, and the air gap between the first lens group and the second lens group during zooming is greater than the wide-angle end than the telephoto end. And the distance between the lens groups is changed so that the air distance between the third lens group and the fourth lens group is longer at the telephoto end than at the wide-angle end. Of the entire system Upon correction of the image blur caused by movement, translating the first 5b lens group in a direction perpendicular to the optical axis.

  One of the above objects is achieved by the following camera system. That is, the camera system of the present invention is a camera system that converts an optical image of an object into an electrical image signal and displays and stores the converted image signal, and changes the optical image of the object. An interchangeable lens device including a zoom lens system formed so as to be doubled, and an image pickup device that is detachably connected to the interchangeable lens device and receives an optical image formed by the zoom lens system and converts it into an electrical image signal The zoom lens system includes, in order from the object side to the image side, a first lens group having a positive power, a second lens group having a negative power, and a first lens group having a positive power. A third lens group, a fourth lens group having a negative power, a fifth lens group having a positive power, and a sixth lens group having a negative power, and the fifth lens group from the object side. 5th aren And a 5b lens group disposed via an air space that does not change during zooming, and the air space between the first lens group and the second lens group during zooming At the time of focusing, the distance between the lens groups is changed so that the telephoto end is longer than the wide-angle end, and the air interval between the third lens group and the fourth lens group is longer than the wide-angle end at the telephoto end. In the zoom lens system, the sixth lens group is moved along the optical axis, and the fifth lens group is translated in a direction perpendicular to the optical axis when correcting image blur due to vibration of the entire system.

  According to the present invention, a high-speed autofocus with a maximum half field angle of about 3.3 ° at the telephoto end, an image blur correction function, a compact zoom lens system with good imaging characteristics, and It is possible to provide a camera system using the zoom lens system.

(Embodiments 1 to 7)
FIG. 1 is a lens arrangement diagram of the zoom lens system according to Embodiment 1. FIG. FIG. 5 is a lens arrangement diagram of the zoom lens system according to Embodiment 2. FIG. 9 is a lens arrangement diagram of the zoom lens system according to Embodiment 3. FIG. 13 is a lens arrangement diagram of the zoom lens system according to Embodiment 4. FIG. 17 is a lens arrangement diagram of the zoom lens system according to Embodiment 5. FIG. 21 is a lens layout diagram of the zoom lens system according to Embodiment 6. FIG. 25 is a lens layout diagram of the zoom lens system according to Embodiment 7.

1, 5, 9, 13, 17, 21, and 25 represent the zoom lens system in the infinitely focused state. In each figure, (a) shows the lens configuration at the wide angle end (shortest focal length state: focal length f _W ), and (b) shows the intermediate position (intermediate focal length state: focal length f _M = √ (f _W * f). _T )) shows a lens configuration, and FIG. 8C shows a 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. Therefore, between the wide-angle end and the intermediate position, and between 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. Furthermore, in each figure, the arrow attached to the lens group represents the focusing from the infinite focus state to the close object focus state. That is, the moving direction during focusing from the infinitely focused state to the close object focused state is shown.

  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, and is located on the object side of the image plane S (between the image plane S and the most image side lens surface of the sixth lens group G6). Are provided with a parallel plate P equivalent to an optical low-pass filter, a face plate of an image sensor, or the like. Further, in each drawing, a diaphragm A is provided between the most image side lens surface of the third lens group G3 and the most object side lens surface of the fourth lens group G4.

  The zoom lens system according to each embodiment includes, in order from the object side to the image side, a first lens group G1 having a positive power, a second lens group G2 having a negative power, and a third lens having a positive power. The lens group G3 includes a fourth lens group G4 having negative power, a fifth lens group G5 having positive power, and a sixth lens group G6 having negative power.

  In the first to third embodiments, the first lens group G1 includes, in order from the object side to the image side, a first lens element L1 having a positive power with a convex surface facing the object side, and a negative lens with a convex surface facing the object side. It consists of a cemented lens element formed by cementing the lens element L2 and the positive lens element L3. On the other hand, in the fourth to seventh embodiments, the first lens group G1 includes a cemented lens element formed by cementing a negative lens element L1 having a convex surface facing the object side and a positive lens element L2, and a convex surface facing the object side. And a third lens element L3 having a positive power directed thereto. Any of the configurations of the first lens group G1 may be adopted. However, when the effect of downsizing is further obtained, the first to third embodiments are adopted, and when the effect of the optical performance is obtained, the fourth to fourth embodiments are used. It is desirable to adopt 7.

  The second lens group G2 includes, in order from the object side to the image side, a cemented lens element formed by cementing a fourth lens element L4 having a positive power and a fifth lens element L5 having a negative power. And a sixth lens element L6 having a negative power facing the concave surface. In the zoom lens system of the present invention, it is advantageous to correct various aberrations by increasing the distance between the image-side principal point of the first lens group G1 and the object-side principal point of the second lens group G2 at the wide angle end. The correction of various aberrations tends to be advantageous when the distance between the image side principal point of the second lens group G2 and the object side principal point of the third lens group G3 is shortened. Therefore, if the most object side of the second lens group G2 is a cemented lens element, the object side principal point and the image side principal point of the second lens group G2 are biased toward the image side, so that the first lens group G1 and the second lens group G2 There is an effect that various aberrations can be satisfactorily corrected while securing a necessary amount of the closest distance between the lens group G2 and the closest distance between the second lens group G2 and the third lens group G3. Yes, it is preferable.

  The third lens group G3 includes a seventh lens element having positive power, and a cemented lens element formed by cementing an eighth lens element L8 having positive power and a ninth lens element L9 having negative power. Become. The fourth lens group G4 includes only a cemented lens element formed by cementing a tenth lens element L10 having negative power and an eleventh lens element L11 having negative power.

  The fifth lens group G5 includes, in order from the object side to the image side, a 5a lens group, and a 5b lens group that is arranged with an air gap that does not change during zooming. The 5a lens group includes a twelfth lens element L12 having positive power, a thirteenth lens element L13 having negative power, and a fourteenth lens element L14 having positive power. The 5b lens group includes only a cemented lens element formed by cementing a fifteenth lens element L15 having negative power and a sixteenth lens element L16 having positive power.

  The sixth lens group G6 includes, in order from the object side to the image side, a seventeenth lens element L17 having negative power, an eighteenth lens element L18 having positive power, and a nineteenth lens element L19 having negative power. It consists of a cemented lens element formed by cementing.

  In the zoom lens system of each embodiment, during zooming, the air gap between the first lens group G1 and the second lens group G2 is longer at the telephoto end than at the wide-angle end, and the third lens group G3 and the fourth lens group. The interval between the lens groups is changed so that the air interval between G4 is longer at the telephoto end than at the wide-angle end. Specifically, in the zoom lens system of each embodiment, during zooming from the wide-angle end to the telephoto end, the first lens group G1 moves to the object side, and the second lens group G2 is fixed with respect to the image plane S. Then, the third lens group G3 to the sixth lens group G6 all move toward the object side while changing the distance between them. In focusing, the sixth lens group G6 is moved along the optical axis. Specifically, the zoom lens system of each embodiment moves the sixth lens group G6 to the image side during focusing from the infinite focus state to the close object focus state. Further, when correcting image blur due to vibration of the entire system, the 5b lens group is translated in a direction perpendicular to 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.

  The zoom lens system of each embodiment will be described in more detail. In the zoom lens system of each embodiment, at the wide-angle end, the first lens group G1 and the second lens group G2 approach each other, and the combined power of the first lens group G1 and the second lens group G2 becomes negative. Since the combined power from the lens group G3 to the sixth lens group G6 is positive, the entire lens system has a retrofocus configuration. When the first lens group G1 and the second lens group G2 are made into one lens group, the entire lens system has a power arrangement having good symmetry with negative, positive, negative, positive and negative, and it is easy to correct off-axis aberrations. For example, distortion can be reduced in the entire zoom range.

  On the other hand, in the zoom lens system of each embodiment, at the telephoto end, the power of the first lens group G1 is positive, and the combined power of the second lens group G2 to the sixth lens group G6 is negative. Since the air gap between the group G1 and the second lens group G2 is long, the entire lens system has a telephoto type lens configuration. Therefore, at the telephoto end, the total optical length can be shorter than the focal length of the entire lens system.

  In the zoom lens system of each embodiment, since the entire lens system is composed of six lens groups, the burden on zooming of each lens group is reduced, and various aberrations of the entire lens system can be easily corrected. Furthermore, the zoom lens system of each embodiment can reduce changes in spherical aberration and curvature of field due to changes in shooting distance, and can widen a shooting range in which high-quality shooting can be performed.

  In the zoom lens system of each embodiment, the second lens group G2 can always be fixed in position. In this case, there are five lens groups that move for zooming, and the number of parts of the lens barrel can be reduced accordingly. In focusing, the sixth lens group G6 is moved along the optical axis. Since the sixth lens group G6 is small and light, high-speed driving is possible even with a small motor or actuator, and high-speed autofocus is possible.

Assuming that the focal length of the entire lens system is f and the inclination of the lens system due to camera shake is θ, the image eccentricity eM on the imaging surface of the imaging device can be expressed as follows.
eM = f · tanθ
From the above equation, it can be seen that when the image blur angle θ is the same, the image decentering amount eM increases as the focal length f of the entire lens system increases. In other words, image blur increases as the focal length of the entire lens system increases. Therefore, if the camera shake correction can be realized at a level where there is no practical problem at the telephoto end, the camera shake correction can be realized at a level where there is no practical problem even at other zoom positions.

  In the zoom lens system of each embodiment, when the image blur is optically corrected, the zoom lens system as a whole is increased in size by moving the fifth lens group in the direction perpendicular to the optical axis in this way. It is possible to correct image blur while maintaining excellent imaging characteristics with small decentration coma and decentering astigmatism while suppressing and compact configuration.

  The following description is given for conditions preferable to be satisfied by a zoom lens system having the above basic configuration like the zoom lens systems according to Embodiments 1 to 7. A plurality of preferable conditions are defined for the zoom lens system according to each embodiment, but a zoom lens system configuration that satisfies all of the plurality of conditions is most desirable. However, by satisfying individual conditions, it is possible to obtain a zoom lens system that exhibits the corresponding effects.

All conditions described below are satisfied only under the following two preconditions (A) and (B) unless otherwise specified.
3.8 <f _T / f _W (A)
ω _T <3.3 (B)
here,
ω _T : Maximum half angle of view (°) at the telephoto end
f _T : focal length of the entire system at the telephoto end,
f _W : the focal length of the entire system at the wide angle end.

As in the zoom lens systems according to Embodiments 1 to 7, it is preferable that the zoom lens system having the basic configuration as described above satisfies the following conditional expression (1): 0.4 <f ₁ / f _T < 0.7 (1)
here,
f ₁ : focal length of the first lens group,
f _T is the focal length of the entire system at the telephoto end.

Conditional expression (1) is a condition for satisfactorily correcting the spherical aberration generated in the first lens group and shortening the optical total length by defining the power of the first lens group. When f ₁ / f _T exceeds the lower limit of the conditional expression (1), the spherical aberration generated in the first lens group becomes excessive, and it becomes difficult to correct the spherical aberration with other lens groups. If f ₁ / f _T exceeds the upper limit of conditional expression (1), the air gap between the first lens group and the second lens group at the telephoto end becomes long, and the total optical length becomes long. .

As in the zoom lens systems according to Embodiments 1 to 7, it is preferable that the zoom lens system having the basic configuration as described above satisfies the following conditional expression (2): 0.1 <| f ₂ | / f _T <0.16 (2)
here,
f ₂ : focal length of the second lens group,
f _T is the focal length of the entire system at the telephoto end.

Conditional expression (2) is a condition for shortening the total optical length at the telephoto end by regulating the power of the second lens group. When | f ₂ | / f _T exceeds the lower limit of the conditional expression (2), the most object side surface of the third lens group at the telephoto end as compared with the height of the axial ray in the second lens group Therefore, the length in the optical axis direction required to reduce the height of the on-axis light beam on the most object side surface of the sixth lens group becomes long, so that the total optical length becomes long. . When | f ₂ | / f _T exceeds the upper limit of conditional expression (2), the combined power of the first lens group and the second lens group becomes weak at the wide-angle end. The air interval between the three lens groups becomes long or the back focus becomes long, and in any case, the optical total length at the wide angle end becomes long.

As in the zoom lens systems according to Embodiments 1 to 7, it is preferable that the zoom lens system having the basic configuration as described above satisfies the following conditional expression (3): 0.1 <| f ₄ | / f _T <0.35 (3)
here,
f ₄ : focal length of the fourth lens group,
f _T is the focal length of the entire system at the telephoto end.

Conditional expression (3) regulates the power of the fourth lens group to improve the spherical aberration of the entire lens system and to provide a good balance between the spherical aberration and the change in field curvature when the shooting distance changes. It is a condition to make it. When | f ₄ | / f _T exceeds the lower limit of the conditional expression (3), various aberrations occurring in the fourth lens group become excessive. Therefore, even if an attempt is made to correct these various aberrations with other lens groups, coma aberration Or astigmatism cannot be corrected. If | f ₄ | / f _T exceeds the upper limit of conditional expression (3), it becomes difficult to correct the change in spherical aberration due to the change in shooting distance with the fourth lens group, and the shooting distance has changed. In this case, it becomes difficult to improve the balance between spherical aberration and curvature of field.

As in the zoom lens systems according to Embodiments 1 to 7, it is preferable that the zoom lens system having the above basic configuration satisfies the following conditional expression (4): 0.18 <| f ₆ | / f _T <0.26 (4)
here,
f ₆ : focal length of the sixth lens group,
f _T is the focal length of the entire system at the telephoto end.

Conditional expression (4) reduces the total optical length by restricting the power of the sixth lens group, sets the parallel movement amount of the 5b lens group at the time of camera shake correction to an appropriate value, and corrects various aberrations satisfactorily. It is a condition to do. When | f ₆ | / f _T exceeds the lower limit of the conditional expression (4), it is advantageous to shorten the optical total length, but coma and astigmatism generated in the sixth lens group becomes excessive. It becomes difficult to correct these off-axis aberrations with other lens groups in a balanced manner. If | f ₆ | / f _T exceeds the upper limit of conditional expression (4), the total optical length at the telephoto end becomes long, and the amount of parallel movement of the 5b lens group at the time of camera shake correction becomes excessive. The actuator for translating the 5b lens group becomes large, and it is difficult to make the lens barrel compact.

As in the zoom lens systems according to Embodiments 1 to 7, it is preferable that the zoom lens system having the basic configuration as described above satisfies the following conditional expression (5): 0.2 <f _5b / f _T < 0.3 (5)
here,
f _5b : focal length of the 5b lens group,
f _T is the focal length of the entire system at the telephoto end.

Conditional expression (5) is a condition for regulating the amount of translation of the 5b lens group that is translated for image blur correction. When f _5b / f _T exceeds the lower limit of the conditional expression (5), since the outer diameters of the two lens elements constituting the 5b lens group are both large, the 5b lens group becomes heavy, and the 5b The actuator that translates the lens group becomes large, which is contrary to the intention of the present invention to make the lens barrel compact. If f _5b / f _T exceeds the upper limit of conditional expression (5), the amount of parallel movement of the 5b lens group at the time of camera shake correction becomes large, the actuator becomes large, and the lens barrel becomes compact. I can't.

Further, it is desirable that the 5b lens group includes a lens element having a positive power and a lens element having a negative power, and satisfies the following conditional expression (6).
n _p > 1.65 (6)
here,
n _p is the refractive index of the positive lens element of the 5b lens group.

Conditional expression (6) is a condition for satisfactorily correcting decentration coma and decentering astigmatism upon image blur correction by defining the refractive index of the positive lens constituting the 5b lens group. If n _p does not satisfy the conditional expression (6), either decentration coma aberration or decentering astigmatism becomes excessive, so that the image formation characteristic is lowered only in a part of the screen during image blur correction. End up.

As in the zoom lens systems according to Embodiments 1 to 7, it is preferable that the zoom lens system having the above-described basic configuration satisfies the following conditional expression (7): 2.1 <β _6T <2.7 ... (7)
here,
β _6T is the magnification in the infinitely focused state at the telephoto end of the sixth lens group.

Conditional expression (7) defines the magnification at the telephoto end of the sixth lens group, thereby shortening the total optical length, setting the parallel movement amount of the fifth lens group during camera shake correction to an appropriate value, and various aberrations. This is a condition for good correction. If β _6T exceeds the lower limit of conditional expression (7), the total optical length at the telephoto end becomes long, and the amount of translation of the 5b lens group at the time of camera shake correction becomes excessive, and the 5b lens group is translated. Therefore, it is difficult to make the lens barrel compact. Further, when β _6T exceeds the upper limit of conditional expression (7), it is advantageous to shorten the optical total length, but coma and astigmatism generated in the sixth lens group becomes excessive, and these off-axis It becomes difficult to correct aberrations with other lens groups in a balanced manner.

(Embodiment 8)
FIG. 29 is a schematic diagram of a camera system according to the eighth embodiment. 29, the camera system mainly includes an interchangeable lens device 300 and a camera body 400. The interchangeable lens device 300 is detachable from the camera main body 400. The interchangeable lens device 300 holds an imaging lens system 301 therein. The imaging lens system 301 is the zoom lens system according to any one of Embodiments 1 to 7 described above. The camera body includes, for example, a quick return mirror 401 for switching an optical path, an image sensor 402 that receives an optical image formed by a zoom lens system, and converts it into an electrical image signal, a liquid crystal display 403, and a focusing screen 404, a pentaprism 405, and an eyepiece lens system 406.

  Since the camera system according to Embodiment 8 includes the zoom lens system according to any one of Embodiments 1 to 7, it is possible to generate an electrical image signal based on a good optical image.

  Hereinafter, numerical examples in which the zoom lens systems according to Embodiments 1 to 7 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, and vd is an Abbe number with respect to the d line.

  FIG. 2 is a longitudinal aberration diagram of the zoom lens system according to Example 1 when the zoom lens system is in focus at infinity. FIG. 6 is a longitudinal aberration diagram of the zoom lens system according to Example 2 when the zoom lens system is in focus at infinity. FIG. 10 is a longitudinal aberration diagram of the zoom lens system according to Example 3 when the zoom lens system is in focus at infinity. FIG. 14 is a longitudinal aberration diagram of the zoom lens system according to Example 4 when the zoom lens system is in focus at infinity. FIG. 18 is a longitudinal aberration diagram of the zoom lens system according to Example 5 when the zoom lens system is in focus at infinity. FIG. 22 is a longitudinal aberration diagram of the zoom lens system according to Example 6 when the zoom lens system is in focus at infinity. FIG. 26 is a longitudinal aberration diagram of the zoom lens system according to Example 7 at the infinite focus state.

  FIG. 3 is a longitudinal aberration diagram of the zoom lens system according to Example 1 in a close object focusing state (object distance: 4 m). FIG. 7 is a longitudinal aberration diagram of the zoom lens system according to Example 2 in a close object focusing state (object distance: 4 m). FIG. 11 is a longitudinal aberration diagram of the zoom lens system according to Example 3 in a close object focusing state (object distance: 4 m). FIG. 15 is a longitudinal aberration diagram of the zoom lens system according to Example 4 in a close object focusing state (object distance: 4 m). FIG. 19 is a longitudinal aberration diagram of the zoom lens system according to Example 5 in a close object in-focus state (object distance 4 m). FIG. 23 is a longitudinal aberration diagram of a zoom lens system according to Example 6 in a close object in-focus state (object distance 4 m). FIG. 27 is a longitudinal aberration diagram of a zoom lens system according to Example 7 in a close object in-focus state (object distance 4 m).

  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).

  FIG. 4 is a lateral aberration diagram in a basic state where image blur correction is not performed and in an image blur correction state at the telephoto end of the zoom lens system according to Example 1. FIG. 8 is a lateral aberration diagram in a basic state where image blur correction is not performed and in an image blur correction state at the telephoto end of the zoom lens system according to Example 2. FIG. 12 is a lateral aberration diagram in a basic state where image blur correction is not performed and in an image blur correction state at the telephoto end of the zoom lens system according to Example 3. FIG. 16 is a lateral aberration diagram in a basic state where image blur correction is not performed and in an image blur correction state at the telephoto end of a zoom lens system according to Example 4. FIG. 20 is a lateral aberration diagram in a basic state where image blur correction is not performed and in an image blur correction state at the telephoto end of a zoom lens system according to Example 5. FIG. 24 is a lateral aberration diagram in a basic state where image blur correction is not performed and in an image blur correction state at the telephoto end of a zoom lens system according to Example 6. FIG. 28 is a lateral aberration diagram in a basic state where image blur correction is not performed and in an image blur correction state at the telephoto end of a zoom lens system according to Example 7.

  In each lateral aberration diagram, the upper three aberration diagrams show the basic state where image blur correction is not performed at the telephoto end, and the lower three aberration diagrams show that the entire 5b lens group is moved by a predetermined amount in a direction perpendicular to the optical axis. This corresponds to the image blur correction state at the telephoto end. In each lateral aberration diagram in the basic state, the upper row shows the lateral aberration at the image point of + 70% of the maximum image height, the middle row shows the lateral aberration at the axial image point, and the lower row shows the lateral aberration at the image point of −70% of the maximum image height. Respectively. In each lateral aberration diagram in the image blur correction state, the upper stage is the lateral aberration at the image point of + 70% of the maximum image height, the middle stage is the lateral aberration at the axial image point, and the lower stage is at the image point of −70% of the maximum image height. Each corresponds to lateral aberration. In each lateral aberration diagram, the horizontal axis represents the distance from the principal ray on the pupil plane, 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) characteristics. In each lateral aberration diagram, the meridional plane is a plane including the optical axis of the first lens group G1 and the optical axis of the 5b lens group.

  The amount of movement of the 5b lens group in the direction perpendicular to the optical axis in the image blur correction state is 0.498 mm in Example 1, 0.504 mm in Example 2, and 0 in Example 3 at the telephoto end. .502 mm, Example 4 is 0.634 mm, Example 5 is 0.618 mm, Example 6 is 0.618 mm, and Example 7 is 0.618 mm. Note that when the shooting distance is ∞ and the zoom lens system is tilted by about 0.25 ° at the telephoto end, the entire amount of the 5b lens unit is translated in the direction perpendicular to the optical axis by the above values. It is equal to the amount of image eccentricity when

  As can be seen from the respective lateral aberration diagrams, the symmetry of the lateral aberration at the axial image point is good. Further, when the lateral aberration at the + 70% image point and the lateral aberration at the -70% image point are compared in the basic state, the curvature is small and the inclinations of the aberration curves are almost equal. It can be seen that the aberration is small. This means that sufficient imaging performance is obtained even in the image blur correction state. When the image blur correction angle of the zoom lens system is the same, the amount of parallel movement required for image blur correction decreases as the focal length of the entire zoom lens system decreases. Therefore, at any zoom position, it is possible to perform sufficient image blur correction without deteriorating the imaging characteristics for an image blur correction angle up to about 0.25 °.

(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, and Table 2 shows various data.

Table 1 (surface data)

Surface number rd nd vd
1 70.26600 3.18000 1.48749 70.4
2 271.90200 0.20000
3 58.17900 1.60000 1.80610 33.3
4 37.27500 5.80000 1.49700 81.6
5 807.29500 Variable
6 128.23200 2.45000 1.80518 25.5
7 -45.73000 0.90000 1.71300 53.9
8 27.07600 2.94600
9 -25.81600 0.90000 1.62299 58.1
10 -4564.74100 Variable
11 51.86000 3.02000 1.49700 81.6
12 -36.08900 0.15000
13 38.92200 2.20000 1.60311 60.7
14 -222.70400 0.90000 1.67270 32.2
15 83.91000 2.00000
16 (Aperture) ∞ Variable
17 -25.21500 0.90000 1.60311 60.7
18 87.92100 1.71000 1.64769 33.8
19 -107.17800 Variable
20 -237.28500 2.06000 1.48749 70.4
21 -35.93200 0.15000
22 113.33600 0.90000 1.80518 25.5
23 33.37700 0.42400
24 50.31100 2.53000 1.51680 64.2
25 -72.23900 0.80000
26 33.72800 3.32000 1.77250 49.6
27 -67.96000 0.70000 1.80518 25.5
28 1072.43900 Variable
29 125.35800 0.90000 1.83481 42.7
30 17.70400 0.60000
31 17.46600 4.06000 1.68893 31.2
32 -53.83700 0.90000 1.77250 49.6
33 32.62200 Variable
34 ∞ 4.60000 1.51680 64.2
35 ∞ 0.99973
Image plane ∞

Table 2 (various data)

Zoom ratio 3.84276
Wide angle Medium telephoto Focal length 51.0024 99.9796 195.9903
F number 4.01723 4.86955 5.81192
Angle of View 12.3035 6.2293 3.1761
Image height 11.0000 11.0000 11.0000
Optical total length 129.7258 153.3123 169.4992
BF 0.99997 1.00050 0.99973
d5 2.3310 25.9171 42.1047
d10 15.6740 10.4224 3.2793
d16 4.2923 6.9363 11.4821
d19 13.7118 8.1835 3.3093
d28 9.9421 6.8762 1.7166
d33 31.9746 43.1763 55.8075

(Numerical example 2)
The zoom lens system of Numerical Example 2 corresponds to Embodiment 2 shown in FIG. Table 3 shows surface data of the zoom lens system of Numerical Example 2, and Table 4 shows various data.

Table 3 (surface data)

Surface number rd nd vd
1 69.41900 3.18000 1.48749 70.4
2 258.63300 0.20000
3 58.15700 1.60000 1.80610 33.3
4 37.24100 5.80000 1.49700 81.6
5 787.44800 Variable
6 126.32700 2.46000 1.80518 25.5
7 -45.61000 0.90000 1.71300 53.9
8 27.03600 2.95900
9 -25.64700 0.90000 1.62299 58.1
10 -2019.57400 Variable
11 52.03700 3.03000 1.49700 81.6
12 -35.95700 0.15000
13 38.84900 2.21000 1.60311 60.7
14 -220.41300 0.90000 1.67270 32.2
15 82.92800 2.00000
16 (Aperture) ∞ Variable
17 -25.17300 0.90000 1.60311 60.7
18 84.16200 1.75000 1.64769 33.8
19 -107.92900 Variable
20 -213.08900 2.07000 1.48749 70.4
21 -35.40000 0.15000
22 115.81300 0.90000 1.80518 25.5
23 33.54900 0.44200
24 51.80800 2.59000 1.51680 64.2
25 -66.05000 0.80000
26 31.73000 3.23000 1.72916 54.7
27 -90.75500 0.70000 1.80518 25.5
28 1092.26900 Variable
29 131.79100 0.90000 1.83481 42.7
30 17.48700 0.60000
31 17.30 100 4.09000 1.68893 31.2
32 -56.42900 0.90000 1.77250 49.6
33 33.28600 Variable
34 ∞ 4.60000 1.51680 64.2
35 ∞ 1.00028
Image plane ∞

Table 4 (various data)

Zoom ratio 3.84300
Wide angle Medium telephoto Focal length 51.0001 99.9789 195.9933
F number 4.01054 4.86160 5.81089
Angle of View 12.3152 6.2335 3.1772
Image height 11.0000 11.0000 11.0000
Optical total length 129.8770 153.5561 169.7665
BF 1.00037 1.00009 1.00028
d5 2.3469 26.0261 42.2364
d10 15.6607 10.4506 3.2807
d16 4.3093 6.9635 11.4685
d19 13.7053 8.1636 3.3678
d28 9.9591 6.8699 1.7322
d33 31.9843 43.1713 55.7696

(Numerical Example 3)
The zoom lens system of Numerical Example 3 corresponds to Embodiment 3 shown in FIG. Table 5 shows surface data of the zoom lens system of Numerical Example 3, and Table 6 shows various data.

Table 5 (surface data)

Surface number rd nd vd
1 69.85000 3.15000 1.48749 70.4
2 257.22000 0.20000
3 57.33400 1.60000 1.80610 33.3
4 37.16600 5.80000 1.49700 81.6
5 760.35000 Variable
6 128.74000 2.45000 1.80518 25.5
7 -45.67000 0.90000 1.71300 53.9
8 26.96000 2.96300
9 -25.64400 0.90000 1.62299 58.1
10 -2716.20000 Variable
11 51.35400 3.03000 1.49700 81.6
12 -36.00500 0.15000
13 39.20600 2.36000 1.60311 60.7
14 -125.99000 0.90000 1.67270 32.2
15 82.75200 2.00000
16 (Aperture) ∞ Variable
17 -24.97200 0.90000 1.60311 60.7
18 56.07400 2.03000 1.64769 33.8
19 -99.89100 Variable
20 -204.76000 2.02000 1.48749 70.4
21 -36.40000 0.15000
22 145.01000 0.90000 1.80518 25.5
23 34.84500 0.47600
24 57.69900 2.66000 1.51680 64.2
25 -53.90000 0.80000
26 29.84600 3.32000 1.69680 55.5
27 -93.84000 0.70000 1.80518 25.5
28 1025.18000 Variable
29 141.09500 0.90000 1.83481 42.7
30 17.40300 0.60000
31 17.26300 4.06000 1.68893 31.2
32 -58.43400 0.90000 1.77250 49.6
33 33.98300 Variable
34 ∞ 4.60000 1.51680 64.2
35 ∞ 0.99982
Image plane ∞

Table 6 (various data)

Zoom ratio 3.84306
Wide angle Medium telephoto Focal length 51.0007 99.9810 195.9989
F number 4.00357 4.83714 5.78215
Angle of view 12.3228 6.2370 3.1783
Image height 11.0000 11.0000 11.0000
Optical total length 130.3224 154.0270 169.9736
BF 1.00005 1.00043 0.99982
d5 2.3125 26.0167 41.9640
d10 15.4807 10.5000 3.2811
d16 4.3419 6.9833 11.3888
d19 13.7357 8.1071 3.3666
d28 10.0717 6.8389 1.7313
d33 31.9609 43.1616 55.8230

(Numerical example 4)
The zoom lens system of Numerical Example 4 corresponds to Embodiment 4 shown in FIG. Table 7 shows surface data of the zoom lens system of Numerical Example 4 and Table 8 shows various data.

Table 7 (surface data)

Surface number rd nd vd
1 72.75400 1.77000 1.80610 33.3
2 47.31300 5.88000 1.49700 81.6
3 375.29800 0.20800
4 92.73800 3.87000 1.49700 81.6
5 -1170.85900 Variable
6 104.42600 2.89000 1.80518 25.5
7 -56.11200 0.93000 1.69680 55.5
8 27.58400 3.38500
9 -35.39300 0.94000 1.48749 70.4
10 69.12300 Variable
11 38.89200 3.33000 1.49700 81.6
12 -66.37000 0.20800
13 27.38400 3.96000 1.48749 70.4
14 -64.46800 1.04000 1.80518 25.5
15 406.00600 Variable
16 (Aperture) ∞ 3.00000
17 -22.97800 2.15000 1.80610 33.3
18 -12.50000 0.70000 1.69680 55.5
19 68.07200 Variable
20 -103.27400 2.22000 1.51680 64.2
21 -22.74100 0.20800
22 133.98400 3.31000 1.56384 60.8
23 -18.79000 0.72800 1.80610 40.7
24 -51.52500 0.48800
25 36.23600 3.05000 1.72916 54.7
26 -37.79900 0.73000 1.72825 28.3
27 386.76000 Variable
28 76.49400 0.73000 1.75500 52.3
29 18.29700 0.80000
30 18.20500 3.27000 1.64769 33.8
31 -137.18600 0.73000 1.77250 49.6
32 30.91000 Variable
33 ∞ 4.60000 1.51680 64.2
34 ∞ 0.99990
Image plane ∞

Table 8 (various data)

Zoom ratio 3.84258
Wide angle Medium telephoto Focal length 51.0022 99.9786 195.9796
F number 4.12088 4.84317 5.60097
Angle of View 12.1828 6.1864 3.1643
Image height 11.0000 11.0000 11.0000
Optical total length 136.5384 162.3097 179.6471
BF 1.00003 0.99980 0.99990
d5 3.9366 29.7081 47.0455
d10 17.4097 10.8609 3.9819
d15 9.2444 11.8630 15.3296
d19 8.9072 5.9928 2.1744
d27 9.5425 7.1668 1.5459
d32 31.3730 40.5933 53.4449

(Numerical example 5)
The zoom lens system of Numerical Example 5 corresponds to Embodiment 5 shown in FIG. Table 9 shows surface data of the zoom lens system of Numerical Example 5 and Table 10 shows various data.

Table 9 (surface data)

Surface number rd nd vd
1 72.92800 1.70000 1.80610 33.3
2 47.58400 5.81000 1.49700 81.6
3 355.60600 0.20000
4 93.04300 3.84000 1.49700 81.6
5 -1292.04200 Variable
6 106.46000 2.80000 1.80518 25.5
7 -58.69300 1.00000 1.69680 55.5
8 27.58400 3.39000
9 -35.32400 0.93000 1.48749 70.4
10 71.31300 Variable
11 40.48200 3.29000 1.49700 81.6
12 -64.72400 0.20000
13 27.01400 3.95000 1.48749 70.4
14 -66.63500 1.00000 1.80518 25.5
15 542.40500 Variable
16 (Aperture) ∞ 3.00000
17 -23.19800 2.13000 1.80610 33.3
18 -12.62800 0.75000 1.69680 55.5
19 67.33500 Variable
20 -90.91500 2.25000 1.51680 64.2
21 -21.79900 0.20000
22 122.46800 3.37000 1.56384 60.8
23 -18.48600 0.75000 1.80610 40.7
24 -56.20500 0.50000
25 35.33200 3.10000 1.72916 54.7
26 -37.20300 0.75000 1.72825 28.3
27 388.35300 Variable
28 ∞ 0.00000
29 90.89800 0.75000 1.77250 49.6
30 19.17500 0.80000
31 19.12000 3.13000 1.67270 32.2
32 -153.43400 0.75000 1.77250 49.6
33 31.40000 Variable
34 ∞ 4.60000 1.51680 64.2
35 ∞ 1.00000
Image plane ∞

Table 10 (various data)

Zoom ratio 3.84316
Wide angle Medium telephoto Focal length 50.9998 99.9798 196.0001
F number 4.07509 4.78302 5.54165
Angle of View 12.3667 6.2780 3.2070
Image height 11.1820 10.9990 10.9820
Optical total length 136.1616 162.3840 179.8948
BF 0.99975 0.99974 1.00000
d5 3.9370 30.1593 47.6690
d10 17.3561 10.7424 3.8401
d15 9.2079 11.8077 15.3253
d19 9.0498 6.1354 2.1744
d27 9.3330 6.9926 1.6070
d34 31.3380 40.6069 53.3390

(Numerical example 6)
The zoom lens system of Numerical Example 6 corresponds to Embodiment 6 shown in FIG. Table 11 shows surface data of the zoom lens system of Numerical Example 6 and Table 12 shows various data.

Table 11 (surface data)

Surface number rd nd vd
1 73.66000 1.70000 1.80610 33.3
2 46.74900 5.75000 1.49700 81.6
3 288.49700 0.20000
4 86.79800 4.15000 1.48749 70.4
5 -776.18100 Variable
6 108.92600 2.79000 1.80518 25.5
7 -58.57100 1.00000 1.69680 55.5
8 27.27200 3.34000
9 -37.14700 0.93000 1.48749 70.4
10 72.02000 Variable
11 39.98100 3.29000 1.49700 81.6
12 -65.91900 0.20000
13 26.59500 4.01000 1.48749 70.4
14 -65.42000 1.00000 1.80518 25.5
15 473.28200 Variable
16 (Aperture) ∞ 3.00000
17 -23.03300 2.17000 1.80610 33.3
18 -12.44600 0.75000 1.69680 55.5
19 67.69200 Variable
20 -85.30600 2.24000 1.51680 64.2
21 -21.62600 0.20000
22 114.28500 3.42000 1.56384 60.8
23 -18.37200 0.75000 1.80610 40.7
24 -56.40500 0.50000
25 35.49100 3.05000 1.72916 54.7
26 -38.39800 0.75000 1.72825 28.3
27 373.84800 Variable
28 91.37400 0.75000 1.77250 49.6
29 19.41600 0.80000
30 19.30700 3.11000 1.67270 32.2
31 -154.25100 0.75000 1.77250 49.6
32 31.15000 Variable
33 ∞ 4.60000 1.51680 64.2
34 ∞ 0.99977
Image plane ∞

Table 12 (various data)

Zoom ratio 3.84277
Wide angle Medium telephoto Focal length 51.0017 99.9821 195.9878
F number 4.07161 4.77163 5.58817
Angle of View 12.1666 6.1849 3.1660
Image height 11.0000 11.0000 11.0000
Optical total length 136.5435 163.0256 180.0212
BF 0.99986 1.00022 0.99977
d5 3.8956 30.3775 47.3733
d10 17.4195 10.7987 3.6973
d15 9.0576 11.6208 15.2607
d19 9.3084 6.4384 2.1744
d27 9.2979 6.8410 1.8269
d32 31.3646 40.7490 53.4888

(Numerical example 7)
The zoom lens system of Numerical Example 7 corresponds to Embodiment 7 shown in FIG. Table 13 shows surface data of the zoom lens system of Numerical Example 7, and Table 14 shows various data.

Table 13 (surface data)

Surface number rd nd vd
1 81.45500 1.70000 1.74950 35.0
2 48.56500 5.66000 1.49700 81.6
3 343.86800 0.20000
4 85.25500 4.14000 1.49700 81.6
5 -986.18000 Variable
6 107.89700 2.76000 1.80518 25.5
7 -60.67700 1.00000 1.69680 55.5
8 27.57700 3.38000
9 -35.65600 0.93000 1.48749 70.4
10 74.16900 Variable
11 41.33100 3.29000 1.49700 81.6
12 -63.01500 0.20000
13 26.68500 3.97000 1.48749 70.4
14 -68.08400 1.00000 1.80518 25.5
15 514.81500 Variable
16 (Aperture) ∞ 3.00000
17 -23.22800 2.14000 1.80610 33.3
18 -12.60000 0.75000 1.69680 55.5
19 66.04200 Variable
20 -92.34600 2.27000 1.51680 64.2
21 -21.69300 0.20000
22 127.09800 3.38000 1.56384 60.8
23 -18.40500 0.75000 1.80610 40.7
24 -56.57700 0.50000
25 35.65500 3.09000 1.72916 54.7
26 -36.90300 0.75000 1.72825 28.3
27 429.21000 Variable
28 93.17700 0.75000 1.77250 49.6
29 19.31300 0.80000
30 19.18900 3.15000 1.67270 32.2
31 -137.14000 0.75000 1.77250 49.6
32 31.35500 Variable
33 ∞ 4.60000 1.51680 64.2
34 ∞ 0.99978
Image plane ∞

Table 14 (various data)

Zoom ratio 3.84297
Wide angle Medium telephoto Focal length 51.0063 99.9930 196.0157
F number 4.09171 4.79964 5.56873
Angle of View 12.1831 6.1876 3.1651
Image height 11.0000 11.0000 11.0000
Optical total length 136.1719 162.4083 179.8314
BF 0.99992 0.99986 0.99978
d5 3.9335 30.1698 47.5930
d10 17.3089 10.6816 3.6971
d15 8.8817 11.6133 15.2900
d19 9.2150 6.2477 2.1744
d27 9.3407 6.9493 1.6247
d32 31.3822 40.6367 53.3424

  Table 15 below shows the corresponding values for each condition in the zoom lens system of each numerical example.

Table 15 (corresponding values of conditions)

Conditional Example Example 1 Example 2 Example 3 Example 4 Example 5 Example 6 Example 7
(1) 0.500 0.501 0.495 0.571 0.579 0.581 0.580
(2) 0.120 0.120 0.119 0.138 0.138 0.139 0.139
(3) 0.298 0.297 0.308 0.139 0.139 0.139 0.139
(4) 0.197 0.197 0.197 0.243 0.240 0.239 0.238
(5) 0.235 0.238 0.237 0.278 0.270 0.273 0.271
(6) 1.77250 1.72916 1.69680 1.72916 1.72916 1.72916 1.72916
(7) 2.569 2.570 2.577 2.218 2.232 2.239 2.242

  The zoom lens system according to the present invention is applicable to digital input devices such as a digital still camera, a digital video camera, a mobile phone device, a PDA (Personal Digital Assistance), a surveillance camera in a surveillance system, a web camera, an in-vehicle camera, It is particularly suitable for a photographing optical system that requires high image quality, such as a digital still camera and a digital video camera. In particular, the present invention is suitable for an interchangeable lens apparatus that can be attached to and detached from the camera body.

Lens arrangement diagram showing an infinitely focused state of the zoom lens system according to Embodiment 1 (Example 1) Longitudinal aberration diagram of the zoom lens system according to Example 1 in an infinite focus state Longitudinal aberration diagram of the close-up object in-focus state (object distance 4 m) of the zoom lens system according to Example 1 Lateral aberration diagram in the basic state where image blur correction is not performed and in the image blur correction state at the telephoto end of the zoom lens system according to Embodiment 1 Lens arrangement diagram showing an infinitely focused state of the zoom lens system according to Embodiment 2 (Example 2) Longitudinal aberration diagram of the zoom lens system according to Example 2 in an infinitely focused state Longitudinal aberration diagram of the close-up object in-focus state (object distance 4 m) of the zoom lens system according to Example 2 Lateral aberration diagrams in the basic state where image blur correction is not performed and in the image blur correction state at the telephoto end of the zoom lens system according to Example 2 Lens arrangement diagram showing an infinitely focused state of the zoom lens system according to Embodiment 3 (Example 3) Longitudinal aberration diagram of the zoom lens system according to Example 3 in an infinitely focused state Longitudinal aberration diagram of the zoom lens system according to Example 3 in a close object focusing state (object distance: 4 m) Lateral aberration diagram in the basic state where image blur correction is not performed and in the image blur correction state at the telephoto end of the zoom lens system according to Example 3 Lens arrangement diagram showing an infinitely focused state of the zoom lens system according to Embodiment 4 (Example 4) Longitudinal aberration diagram of the zoom lens system according to Example 4 in an infinitely focused state Longitudinal aberration diagram of close-up object focusing state (object distance: 4 m) of the zoom lens system according to Example 4 Lateral aberration diagrams in the basic state where image blur correction is not performed and in the image blur correction state at the telephoto end of the zoom lens system according to Embodiment 4 Lens arrangement diagram showing an infinitely focused state of a zoom lens system according to Embodiment 5 (Example 5) Longitudinal aberration diagram of the zoom lens system according to Example 5 in an infinitely focused state Longitudinal aberration diagram of the close-up object in-focus state (object distance 4 m) of the zoom lens system according to Example 5 Lateral aberration diagrams in the basic state where image blur correction is not performed and in the image blur correction state at the telephoto end of the zoom lens system according to Example 5 Lens arrangement diagram showing an infinitely focused state of a zoom lens system according to Embodiment 6 (Example 6) Longitudinal aberration diagram of the zoom lens system according to Example 6 in focus at infinity Longitudinal aberration diagram of the close-up object in-focus state (object distance 4 m) of the zoom lens system according to Example 6 Horizontal aberration diagram in the basic state where image blur correction is not performed and in the image blur correction state at the telephoto end of the zoom lens system according to Example 6 Lens arrangement diagram showing an infinitely focused state of a zoom lens system according to Embodiment 7 (Example 7) Longitudinal aberration diagram of the zoom lens system according to Example 7 in a focused state at infinity Longitudinal aberration diagram of close-up object focusing state (object distance: 4 m) of zoom lens system according to example 7 Lateral aberration diagrams in the basic state where image blur correction is not performed and in the image blur correction state at the telephoto end of the zoom lens system according to Example 7 Schematic diagram of a camera system according to Embodiment 8

Explanation of symbols

G1 1st lens group G2 2nd lens group G3 3rd lens group G4 4th lens group G5 5th lens group G6 6th lens group A Aperture

Claims (11)

In order from the object side to the image side, a first lens group having a positive power, a second lens group having a negative power, a third lens group having a positive power, and a fourth lens group having a negative power. And a fifth lens group having a positive power and a sixth lens group having a negative power,
The fifth lens group includes a 5a lens group from the object side, and a 5b lens group disposed with an air space that does not change during zooming with the 5a lens group.
During zooming, the air gap between the first lens group and the second lens group is longer at the telephoto end than at the wide angle end, and the air gap between the third lens group and the fourth lens group is at the telephoto end than at the wide angle end. Change the distance between each lens group so that it is long,
During focusing, the sixth lens group is moved along the optical axis,
A zoom lens system that translates the fifth lens group in a direction perpendicular to the optical axis when correcting image blur due to vibration of the entire system.   The zoom lens system according to claim 1, wherein the second lens group is fixed with respect to an image plane.   2. The zoom lens system according to claim 1, wherein the second lens group includes a cemented lens element formed by cementing lens elements having mutually different powers on the most object side. The zoom lens system according to claim 1, satisfying the following conditions:
0.4 <f ₁ / f _T <0.7
(However, f _T / f _W > 3.8, ω _T <3.3)
here,
f ₁ : focal length of the first lens group,
f _T : focal length of the entire system at the telephoto end,
f _W : focal length of the entire system at the wide-angle end,
ω _T : Maximum half angle of view (°) at the telephoto end
It is. The zoom lens system according to claim 1, satisfying the following conditions:
0.1 <| f ₂ | / f _T <0.16
(However, f _T / f _W > 3.8, ω _T <3.3)
here,
f ₂ : focal length of the second lens group,
f _T : focal length of the entire system at the telephoto end,
f _W : focal length of the entire system at the wide-angle end,
ω _T : Maximum half angle of view (°) at the telephoto end
It is. The zoom lens system according to claim 1, satisfying the following conditions:
0.1 <| f ₄ | / f _T <0.35
(However, f _T / f _W > 3.8, ω _T <3.3)
here,
f ₄ : focal length of the fourth lens group,
f _T : focal length of the entire system at the telephoto end,
f _W : focal length of the entire system at the wide-angle end,
ω _T : Maximum half angle of view (°) at the telephoto end
It is. The zoom lens system according to claim 1, satisfying the following conditions:
0.18 <| f ₆ | / f _T <0.26
(However, f _T / f _W > 3.8, ω _T <3.3)
here,
f ₆ : focal length of the sixth lens group,
f _T : focal length of the entire system at the telephoto end,
f _W : focal length of the entire system at the wide-angle end,
ω _T : Maximum half angle of view (°) at the telephoto end
It is. The zoom lens system according to claim 1, satisfying the following conditions:
0.2 <f _5b / f _T <0.3
(However, f _T / f _W > 3.8, ω _T <3.3)
here,
f _5b : focal length of the 5b lens group,
f _T : focal length of the entire system at the telephoto end,
f _W : focal length of the entire system at the wide-angle end,
ω _T : Maximum half angle of view (°) at the telephoto end
It is. The zoom lens system according to claim 1, wherein the fifth lens group includes a lens element having a positive power and a lens element having a negative power, and satisfies the following condition.
n _p > 1.65
here,
n _p is the refractive index of the positive lens element of the 5b lens group. The zoom lens system according to claim 1, satisfying the following conditions:
2.1 <β _6T <2.7
(However, f _T / f _W > 3.8, ω _T <3.3)
here,
β _6T : magnification at the infinite focus state at the telephoto end of the sixth lens group,
f _T : focal length of the entire system at the telephoto end,
f _W : focal length of the entire system at the wide-angle end,
ω _T : Maximum half angle of view (°)
It is. A camera system for converting an optical image of an object into an electrical image signal and displaying and storing the converted image signal,
An interchangeable lens device including a zoom lens system that forms an optical image of an object so as to be variable
A camera body including an image sensor that is detachably connected to the interchangeable lens device, receives an optical image formed by the zoom lens system, and converts the optical image into an electrical image signal;
The zoom lens system includes:
In order from the object side to the image side, a first lens group having a positive power, a second lens group having a negative power, a third lens group having a positive power, and a fourth lens group having a negative power. And a fifth lens group having a positive power and a sixth lens group having a negative power,
The fifth lens group includes a 5a lens group from the object side, and a 5b lens group disposed with an air space that does not change during zooming with the 5a lens group.
During zooming, the air gap between the first lens group and the second lens group is longer at the telephoto end than at the wide angle end, and the air gap between the third lens group and the fourth lens group is at the telephoto end than at the wide angle end. Change the distance between each lens group so that it is long,
During focusing, the sixth lens group is moved along the optical axis,
A camera system, which is a zoom lens system, that translates the fifth lens group in a direction perpendicular to the optical axis when correcting image blur due to vibration of the entire system.

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