JP6675252B2 - Variable power optical system and image pickup apparatus provided with the same - Google Patents

Description

  The present invention relates to a variable power optical system and an imaging apparatus including the same.

  2. Description of the Related Art In recent years, imaging optical systems have been used in a wide range of fields, such as digital cameras, video cameras, surveillance cameras, and cameras for videoconferencing systems.

  As such an imaging optical system, a zoom optical system is used. As a zoom optical system, there are zoom optical systems disclosed in Patent Literature 1, Patent Literature 2, and Patent Literature 3. The zoom optical system of Patent Document 1 includes, in order from the object 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, A fourth lens group having a positive refractive power.

  The zoom optical systems disclosed in Patent Literature 2 and Patent Literature 3 include, in order from the object side, a first lens group having a positive refractive power, a second lens group having a negative refractive power, and a positive refractive power. A third lens group, a fourth lens group having a negative refractive power, and a fifth lens group having a positive refractive power.

JP 2012-11285 A JP 2011-221554 A JP 2001-350093 A

  However, in Patent Documents 1 to 3, securing of a wide angle of view at the wide-angle end, securing of a small F-number, and favorable correction of various aberrations cannot be performed at the same time.

  The present invention has been made in view of such a problem, and a variable power optical system that can secure a wide angle of view and a small F-number at a wide-angle end, and in which various aberrations are satisfactorily corrected. And an imaging device provided with the same.

In order to solve the above-described problems and achieve the object, a variable power optical system according to the present invention includes:
From the object side,
A first lens group having a positive refractive power;
A second lens group having a negative refractive power;
A third lens group having a positive refractive power;
A fourth lens group having a negative refractive power;
A fifth lens group having a positive refractive power;
And a sixth lens group consists of,
The sixth lens group includes a negative lens and a positive lens,
At the time of at least one of zooming, focusing, or camera shake correction, each lens group moves relatively differently with respect to the adjacent lens group,
The second lens group moves so that the distance between the first lens group and the second lens group increases at the telephoto end from the wide-angle end,
The aperture stop is located between the lens surface closest to the image side in the second lens group and the lens surface closest to the image side in the third lens group, or the image stop in the third lens group. It is adjacent to the lens surface located on the side ,
During zooming, the fourth lens group is fixed,
The fourth lens group moves in a direction orthogonal to the optical axis,
During zooming, the sixth lens group is fixed,
The first lens group includes a negative lens and two positive meniscus lenses both having a convex surface facing the object side,
The first lens group has no reflecting surface,
The fifth lens group includes a single lens or a cemented lens,
And wherein to Rukoto and satisfies the following conditional expression (1).
0.012 ≦ DG5G6aw / fG5 ≦ 5.0 (1)
here,
DG5G6aw is an air gap between the fifth lens unit and the sixth lens unit at the wide-angle end,
fG5 is the focal length of the fifth lens group,
It is.

In addition, the imaging device of the present invention,
Optics,
An imaging element having an imaging surface and converting an image formed on the imaging surface by the optical system into an electric signal,
The optical system is any one of the above-described zoom optical systems.

  According to the present invention, it is possible to provide a variable power optical system which can secure a wide angle of view and a small F-number at the wide angle end and in which various aberrations are satisfactorily corrected, and an image pickup apparatus including the same. it can.

FIG. 2 is a lens cross-sectional view of a variable power optical system according to the first embodiment. FIG. 7 is a lens cross-sectional view of a variable power optical system according to a second embodiment. FIG. 10 is a lens cross-sectional view of a variable power optical system according to a third embodiment. FIG. 14 is a lens cross-sectional view of a zoom optical system according to a fourth embodiment. FIG. 14 is a lens cross-sectional view of a zoom optical system according to a fifth embodiment. FIG. 14 is a lens cross-sectional view of a zoom optical system according to a sixth embodiment. FIG. 3 is an aberration diagram of the variable power optical system according to the first exemplary embodiment. FIG. 10 is an aberration diagram of a variable power optical system according to the second embodiment. FIG. 10 is an aberration diagram of a variable power optical system according to the third embodiment. FIG. 14 is an aberration diagram of a variable power optical system according to the fourth embodiment. FIG. 14 is an aberration diagram of the variable power optical system of the fifth example. FIG. 14 is an aberration diagram of the variable power optical system of the sixth embodiment. It is sectional drawing of an imaging device. It is a front perspective view of an imaging device. It is a rear perspective view of an imaging device. FIG. 3 is a configuration block diagram of an internal circuit of a main part of the imaging device. FIG. 1 is a diagram illustrating a configuration of a video conference system.

  Prior to the description of the embodiment, the operation and effect of the embodiment according to an aspect of the present invention will be described. In describing the operation and effect of the present embodiment specifically, a specific example will be described. However, as in the case of the embodiments described later, the illustrated embodiments are only a part of the embodiments included in the present invention, and there are many variations in the embodiments. Therefore, the present invention is not limited to the illustrated embodiment.

  In the following description, “corrected” means that the aberration amount is equal to or less than an allowable value for aberration correction. Further, the camera shake correction means that the amount of image blur caused by the camera shake is less than or equal to an allowable value.

  The basic configuration of the variable power optical system according to the first embodiment and the variable power optical system according to the second embodiment (hereinafter, referred to as “power variable optical system according to the present embodiment”) will be described. In addition, when the technical significance of the same configuration has been described, the description will be omitted. Regarding the technical significance of the conditional expression, for example, the technical significance of the conditional expression (1) and the technical significance of the conditional expression (1- *) (* is a number) are the same, and therefore the conditional expression (1- Description of the technical significance of *) is omitted. In the following description, the lens component means a single lens or a cemented lens.

  The basic configuration of the variable power optical system according to the present embodiment includes, in order from the object side, a first lens group having a positive refractive power, a second lens group having a negative refractive power, and a third lens group having a positive refractive power. A lens group, a fourth lens group having a negative refractive power, a fifth lens group having a positive refractive power, and a sixth lens group. The sixth lens group includes a negative lens and a positive lens. Each of the lens units moves relatively differently with respect to the adjacent lens unit at least at one or more of the time of zooming, the time of focusing, and the time of camera shake correction. The second lens group moves so that the distance between the first lens group and the second lens group at the time of focusing on the object expands from the wide-angle end to the telephoto end. Is located between the lens surface located and the lens surface located closest to the image side in the third lens group, or , It is adjacent to the lens surface located nearest to the image side in the third lens group.

  The basic configuration includes a first lens group, a second lens group, a third lens group, a fourth lens group, and a fifth lens group. In this case, the order of the refractive power can be a positive refractive power, a negative refractive power, a positive refractive power, a negative refractive power, and a positive refractive power. Therefore, in the basic configuration, the arrangement of the refractive power is symmetric about the third lens group. As a result, it is possible to secure a wide angle of view and a high zoom ratio at the wide-angle end while shortening the overall length of the optical system.

  Here, for example, a case where the half angle of view exceeds 25 degrees is referred to as a wide angle of view. Further, for example, a case where the zoom ratio exceeds 5.5 times is referred to as a high zoom ratio. However, it is not limited to this value.

  In the basic configuration, the arrangement of the refractive power is substantially symmetric or symmetric over a wide range of the variable power range. Therefore, it is possible to shorten the entire length of the optical system and to correct aberrations in a wide zoom range. As for the aberration correction, it is possible to correct the field curvature and the coma mainly in a wide range of the variable power range.

  In the optical system, the diameter of the first lens group is the largest. When the above-described basic configuration is used for the variable power optical system, the refractive power of the fourth lens group can be made negative and the refractive power of the fifth lens group can be made positive. An enlargement optical system can be configured. As a result, the diameter of the first lens group can be reduced.

  As described above, with the basic configuration, in an optical system having a wide angle of view and a high zoom ratio, it is possible to reduce the size of the optical system and ensure good imaging performance.

  Each of the lens units can move relatively differently with respect to the adjacent lens units at least at one of the times of zooming, focusing, and camera shake correction.

  “One or more points in time” refers to at least one of at the time of zooming, at the time of focusing, or at the time of camera shake correction. In the basic configuration, a group of lenses in a minimum unit that can move independently of an adjacent lens is defined as one lens group. One lens group includes one lens or a plurality of lenses.

  For example, in a case where the lens groups are divided from the viewpoint that the distance changes at the time of zooming, it is assumed that the lens groups have been divided into four lens groups. Here, it is assumed that one focusing lens group, one camera shake correction lens group, and a lens group that is neither a focusing lens group nor a camera shake correction lens group exist in the fourth lens group. In this case, the focusing lens group and the camera shake correction lens group are regarded as a lens group that moves differently from the adjacent group. Therefore, the fourth lens group is considered to be composed of at least three lens groups. As a result, if the lens groups are divided from the viewpoint of "moving differently from the adjacent groups", it can be divided into at least six lens groups.

  The aperture stop can be located between the lens surface closest to the image side in the second lens group and the lens surface closest to the image side in the third lens group. Alternatively, the aperture stop can be arranged so as to be adjacent to the lens surface located closest to the image side in the third lens group. Thereby, the diameter of each of the first lens group, the second lens group, and the third lens group can be reduced. In addition, as described above, since the arrangement of the refractive power can be made substantially symmetric about the third lens group, the total length of the optical system can be shortened.

  If the refractive power of each lens group can be increased, the zooming effect can be increased. If the zooming action can be increased, the overall length of the optical system can be reduced and the diameter of the optical system can be reduced. However, when the zooming action becomes large, it becomes difficult to secure good imaging performance over a wide zooming range when securing a small F-number.

  The second lens group can contribute to ensuring a wide angle of view at the wide-angle end. When the zooming action can be increased, chromatic aberration of magnification easily occurs in the second lens group. Even if chromatic aberration of magnification occurs in the second lens group, if the occurrence of chromatic aberration of magnification in the entire optical system can be suppressed, the angle of view at the wide-angle end can be made wider, and the miniaturization of the optical system and the securing of a small F-number can be realized. it can.

  Between the fifth lens group and the image plane, the separation state of the on-axis light beam and the off-axis light beam at the wide-angle end is similar to that of the second lens group. If the lens group can be arranged between the fifth lens group and the image plane, lateral chromatic aberration can be generated in this lens group. At this time, the direction in which chromatic aberration of magnification occurs in this lens group can be reversed from the direction in which chromatic aberration of magnification occurs in the second lens group.

  In the basic configuration, the sixth lens group can be arranged between the fifth lens group and the image plane. The sixth lens group has a negative lens and a positive lens. Therefore, by using the negative lens and the positive lens, the direction in which the chromatic aberration of magnification occurs in the sixth lens group can be reversed from the direction in which the chromatic aberration of magnification occurs in the second lens group.

  As described above, since the sixth lens group can have a function of correcting magnification aberration, chromatic aberration of magnification generated in the second lens group can be corrected by the sixth lens group. As a result, it is possible to correct the chromatic aberration of magnification and to increase the magnification from a wide angle range.

  However, if the chromatic aberration of magnification is mainly corrected, astigmatism and coma may occur. Therefore, if only the chromatic aberration of magnification is mainly suppressed, the imaging performance may be adversely affected. A fifth lens group having a positive refractive power can be arranged on the object side of the sixth lens group. By doing so, the fifth lens group can also suppress generation other than chromatic aberration of magnification.

  When the fifth lens group and the sixth lens group can be separated from each other, the aberration correcting action in the fifth lens group and the aberration correcting action in the sixth lens group can be both increased.

  The fourth lens group can be located between the third lens group and the fifth lens group. The refractive power of the third lens group and the refractive power of the fifth lens group can both be positive. Since the refractive power of the fourth lens group can be made negative, the lateral magnification of the fourth lens group can be increased.

  If the lateral magnification of the lens group can be increased, the ratio between the amount of movement of the lens group and the amount of movement of the image on the image plane can be increased, and the diameter and weight of the lens group can be reduced. The movement of the lens group includes movement in a direction along the optical axis and movement in a direction orthogonal to the optical axis.

  The movement of the lens group in the direction along the optical axis is performed at the time of zooming or focusing. If the lateral magnification of the lens group can be increased, the zooming effect and the focusing sensitivity can be increased. The movement of the lens group in the direction orthogonal to the optical axis is performed at the time of camera shake correction. If the lateral magnification of the lens group can be increased, the camera shake correction sensitivity can be increased. As described above, the lateral magnification of the fourth lens group can be increased. Therefore, the fourth lens group can be used for any of zooming, focusing, and camera shake correction.

  In any of zooming, focusing, and camera shake correction, having a large lateral magnification of the fourth lens group contributes to downsizing of the optical system. As described above, by increasing the lateral magnification of the fourth lens group, the entire optical system can be reduced in size.

The variable power optical system according to the first embodiment has the above-described basic configuration. At the time of variable power, the fourth lens group can be fixed, and the fourth lens group can be moved in a direction orthogonal to the optical axis. It is characterized by satisfying the expression (1).
0.012 ≦ DG5G6aw / fG5 ≦ 5.0 (1)
here,
DG5G6aw is an air gap between the fifth lens unit and the sixth lens unit at the wide-angle end,
fG5 is the focal length of the fifth lens group,
It is.

  When the imaging device is held by hand, the imaging device may vibrate due to camera shake in some cases. When vibration is applied to the optical system due to camera shake, a clear image cannot be obtained due to the influence of the vibration. In order to obtain a clearer and higher resolution image, camera shake correction may be performed in the optical system.

  For example, when the imaging device is fixed to a tripod, or when the imaging device is fixed to an outer wall of a building, and vibration occurs on the fixed side, the vibration can be transmitted to the imaging device. Such vibration may be regarded as the same as vibration due to camera shake. Therefore, the vibration in such a case may be considered to be included in the vibration due to camera shake.

  As described above, the fourth lens group can be used for any of zooming, focusing, and camera shake correction. In the variable power optical system of the first embodiment, the fourth lens group can be moved in a direction orthogonal to the optical axis. Thereby, camera shake correction can be performed.

  The movement of the lens group can be described in terms of a zoom function, a focusing function, and a camera shake correction function. The phrase "the fourth lens group can be fixed at the time of zooming" describes the movement of the fourth lens group from the viewpoint of only the zooming function. Therefore, “the fourth lens group can be fixed at the time of zooming” includes, for example, a mode in which the fourth lens group moves in a direction orthogonal to the optical axis to perform camera shake correction while zooming. Also, a mode may be included in which the fourth lens group moves in a direction along the optical axis in order to simultaneously focus while changing the magnification.

  Since the lateral magnification of the fourth lens group is large, it is better to simply control the position of the fourth lens group. Although the fourth lens group can be used for zooming, the fourth lens group is fixed during zooming. By doing so, an error in the position of the fourth lens group does not occur during zooming. As a result, camera shake correction can be performed with high accuracy while maintaining high imaging performance. Since the weight of the fourth lens group can be reduced, camera shake correction can be performed with high follow-up performance.

  When the lower limit of conditional expression (1) is exceeded, it is possible to obtain the effect of correcting astigmatism and the effect of correcting coma. When falling below the upper limit of conditional expression (1), the sum of the thickness of the fifth lens unit on the optical axis and the thickness of the sixth lens unit on the optical axis decreases. On the object side of the fifth lens group, the lens group moves during zooming. As the sum of the thicknesses of the two lens groups decreases, the movable space of the moving lens group increases. Therefore, a high zoom ratio can be obtained.

The variable power optical system according to the second embodiment has the above-described basic configuration, and can fix the sixth lens unit during zooming, and satisfies the following conditional expression (1-1).
0.014 ≦ DG5G6aw / fG5 ≦ 5.0 (1-1)
here,
DG5G6aw is an air gap between the fifth lens unit and the sixth lens unit at the wide-angle end,
fG5 is the focal length of the fifth lens group,
It is.

  The height of the light beam incident on the sixth lens group changes during zooming. If the sixth lens group is fixed at the time of zooming, it is possible to reduce both the change in the diameter of the central luminous flux incident on the sixth lens group and the change in the height of the peripheral rays. As a result, it becomes easy to suppress a change in chromatic aberration of magnification from the wide-angle end to the telephoto end and to secure a small F-number.

  The center light beam diameter is the diameter of a light beam that forms an image at the center of the image plane. The marginal ray height is the height of a ray that forms an image around the image plane.

  When the lens group is moved near the image plane, dust is likely to be generated due to the movement of the lens group. The sixth lens group can be located near the image plane. If the sixth lens group is prevented from moving along the optical axis, the generation of dust can be reduced. When the image pickup device is arranged on the image plane, dust can be reduced from adhering to the image pickup plane.

  A lens group that moves along the optical axis during focusing (hereinafter, referred to as a “focusing lens group”) can be arranged near the sixth lens group. If the sixth lens group is fixed at the time of zooming, it is not necessary to dispose a zooming actuator near the sixth lens group. Therefore, a focusing actuator can be arranged near the focusing lens group. As a result, the size of the focusing unit can be reduced. The focusing unit can be composed of, for example, a focusing lens group and a focusing actuator.

  As described above, the movement of the lens group can be described in terms of the zoom function, the focusing function, and the camera shake correction function. The phrase "the sixth lens group can be fixed at the time of zooming" describes the movement of the sixth lens group from the viewpoint of only the zooming function. Therefore, "the sixth lens group can be fixed at the time of zooming" includes, for example, a mode in which the sixth lens group moves in a direction orthogonal to the optical axis in order to simultaneously perform camera shake correction while zooming. Also, a mode may be included in which the sixth lens group moves in a direction along the optical axis in order to simultaneously focus while changing the magnification.

  In the variable power optical system of the first embodiment, the sixth lens group can be fixed at the time of variable power.

The zoom optical system according to the second embodiment can satisfy the following conditional expression (1).
0.012 ≦ DG5G6aw / fG5 ≦ 5.0 (1)
here,
DG5G6aw is an air gap between the fifth lens unit and the sixth lens unit at the wide-angle end,
fG5 is the focal length of the fifth lens group,
It is.

  In the variable power optical system of the second embodiment, the fourth lens group can move in at least one of a direction along the optical axis and a direction orthogonal to the optical axis.

  As described above, the weight of the fourth lens group can be reduced. In any of zooming, focusing, and camera shake correction, zooming, focusing, and camera shake correction can be performed with high accuracy and high followability. Further, the size of the optical system can be reduced.

  In the variable power optical system according to the second embodiment, the fourth lens group can move in the direction along the optical axis during variable power.

  By doing so, zooming can be performed with high accuracy and high followability. Further, the size of the optical system can be reduced.

  In the variable power optical system according to the second embodiment, the fourth lens group is zoomed during zooming so that the distance between the third lens group and the fourth lens group at the time of focusing on an object at infinity is wider at the telephoto end than at the wide angle end. You can move.

  The image plane position can be corrected over a wide zoom range. As a result, good imaging performance is obtained.

  In the zoom optical system of the second embodiment, at the time of zooming, the fourth lens group can move to the object side and then move to the image side.

  In this case, the fourth lens group moves along a locus convex toward the object side. Therefore, it is possible to correct the fluctuation of the image plane position in the intermediate focal length state. Further, good imaging performance can be obtained in a wide range of the variable power range.

  In the variable power optical system of the second embodiment, the fourth lens group can move in a direction orthogonal to the optical axis.

  In the variable power optical system according to the second embodiment, the fourth lens group can be fixed during zooming.

  In the variable power optical system of the present embodiment, the fifth lens group can move in at least one of a direction along the optical axis and a direction perpendicular to the optical axis.

  A sixth lens group can be arranged on the image side of the fifth lens group. In this case, the fifth lens group can be located closer to the object side. Since the fourth lens group is arranged on the object side of the fifth lens group, the fifth lens group comes close to the fourth lens group. In this case, since the refractive power of the fourth lens group is a negative refractive power and the refractive power of the fifth lens group is a positive refractive power, the lateral magnification of the fifth lens group can be increased.

  As described above, when the lateral magnification of the lens group can be increased, the ratio between the movement amount of the lens group and the movement amount of the image on the image plane can be increased, and the diameter and weight of the lens group can be reduced. Since the lateral magnification of the fifth lens group can be increased, the fifth lens group can be used for any of zooming, focusing, and camera shake correction.

  In any of zooming, focusing, and camera shake correction, having the fifth lens unit have a large lateral magnification contributes to downsizing of the optical system. As described above, by increasing the lateral magnification of the fifth lens group, the entire optical system can be reduced in size.

  In the variable power optical system according to the present embodiment, the fifth lens group can move in the direction along the optical axis during variable power.

  By doing so, zooming can be performed with high accuracy and high followability. Further, the size of the optical system can be reduced.

  In the variable power optical system of the present embodiment, the fifth lens group can move in the direction along the optical axis at the time of focusing.

  By doing so, focusing can be performed with high accuracy and high tracking performance. Further, the size of the optical system can be reduced.

  In the variable power optical system according to the present embodiment, the distance between the fifth lens unit and the sixth lens unit can be made constant during zooming.

  During zooming, the sixth lens group can be fixed. In this case, if the distance between the fifth lens group and the sixth lens group can be made constant, the fifth lens group can be fixed during zooming.

  Since the lateral magnification of the fifth lens group is large, it is better to simply control the position of the fifth lens group. Although the fifth lens group can be used for zooming, the fifth lens group is fixed during zooming. By doing so, an error in the position of the fifth lens group does not occur during zooming. As a result, camera shake correction and focusing can be performed with high accuracy while maintaining high imaging performance. Since the fifth lens group can be reduced in weight, camera shake correction and focusing can be performed with high tracking performance.

  In the variable power optical system of the present embodiment, the entire length of the variable power optical system can be made constant at the time of variable power.

  When the lens group located closest to the object moves during zooming, the position of the center of gravity of the entire optical system may change. When the position of the center of gravity of the entire optical system changes, the posture at the time of photographing may change from the posture before zooming. As described above, when the lens group located closest to the object moves during zooming, it may be difficult to shoot in a fixed posture.

  If the entire length of the variable power optical system can be kept constant during zooming, the lens group located closest to the object side during zooming can be kept stationary. If the lens group located closest to the object side can be kept stationary during zooming, zooming can be performed with less change in posture during shooting.

  Also, there is no movable part in the lens barrel in appearance. Therefore, when an optical unit is configured using the variable power optical system and the lens barrel according to the present embodiment, an optical unit having higher durability, dust resistance, and waterproofness can be configured. For example, when this optical unit is used for a surveillance camera, the surveillance camera can be installed outdoors for a long period of time.

The variable power optical system according to the present embodiment can satisfy the following conditional expression (2).
0.0 ≦ ΔSS / LTLw ≦ 0.11 (2)
here,
ΔSS is the maximum value of the amount of movement of the aperture stop during zooming,
LTLw is the total length of the variable power optical system at the wide-angle end,
It is.

  By satisfying conditional expression (2), it is possible to reduce a sharp change in the F-number due to zooming. As a result, the amount of change in the aperture diameter of the aperture stop at the time of changing the culture can be reduced. Further, even when the F-number is small, it is possible to maintain a state in which the light quantity fluctuation is small in a wide range of the variable power range.

  Further, electric means may be used for changing the aperture diameter of the aperture stop. As the electric means, for example, there is an electric wire for transmitting an electric signal. At the time of zooming, the transmission path of the electric signal, that is, the length of the electric wire may change with the movement of the aperture stop. By satisfying conditional expression (2), the amount of movement of the aperture stop can be reduced, so that a change in the length of the electric wire can be reduced. As a result, electrical means having a highly durable structure can be realized.

  ΔSS / LTLw = 0 means that the position of the aperture stop is fixed.

The variable power optical system according to the present embodiment can satisfy the following conditional expression (3).
1.30 ≦ | fG2 / fw | ≦ 4.50 (3)
here,
fG2 is the focal length of the second lens group,
fw is the focal length of the variable power optical system at the wide angle end,
It is.

  If the lower limit of conditional expression (3) is exceeded, the angle of the light beam entering the second lens group from the first lens group will be smaller for off-axis rays. As a result, the diameter of the first lens group can be reduced. In addition, both the amount of chromatic aberration of magnification and the amount of distortion near the wide angle end are reduced.

  When the value goes below the upper limit of conditional expression (3), the refractive power of the second lens unit becomes small, so that a wide angle of view can be secured.

The variable power optical system according to the present embodiment can satisfy the following conditional expression (4).
−0.065 ≦ fG2 × PG1G2a ≦ 0.190 (4)
here,
PG1G2a is represented by the following equation:
PG1G2a = 1 / RG1B-1 / RG2F,
RG1B is the radius of curvature of the lens surface of the first lens group located closest to the image,
RG2F is a radius of curvature of a lens surface of the second lens group located closest to the object,
It is.

  If the lower limit of conditional expression (4) is exceeded, mainly the occurrence of astigmatism and the change in distortion can be reduced near the wide-angle end. As a result, the angle of view at the wide-angle end can be widened.

  When falling below an upper limit value of conditional expression (4), the refractive power of the second lens group can be reduced. Therefore, even if the angle of view at the wide-angle end is widened, the diameter of the second lens group can be reduced.

The variable power optical system according to the present embodiment can satisfy the following conditional expression (5).
−0.11 ≦ (LTLt−LTLw) /LTLw≦0.11 (5)
here,
LTLt is the total length of the variable power optical system at the telephoto end,
LTLw is the total length of the variable power optical system at the wide-angle end,
It is.

  If the lower limit of conditional expression (5) is exceeded, an increase in field curvature near the wide-angle end can be suppressed while achieving a high zoom ratio, and spherical aberration near the telephoto end can be reduced. The increase can be suppressed. Therefore, good imaging performance can be obtained.

  When falling below the upper limit value of conditional expression (5), it is possible to suppress an increase in the moving amount of the first lens unit during zooming. If the increase in the amount of movement of the first lens group can be suppressed, zooming can be performed with the posture during shooting stabilized. Therefore, stable shooting can be performed.

The zoom optical system according to the present embodiment can satisfy the following conditional expression (6).
4.0 ≦ fG1 / fw ≦ 35 (6)
here,
fG1 is the focal length of the first lens group,
fw is the focal length of the variable power optical system at the wide angle end,
It is.

  When the value exceeds the lower limit of conditional expression (6), the position of the entrance pupil can be kept from moving away from the lens surface closest to the object side to the image side. Therefore, even if the angle of view at the wide-angle end is widened, the diameter of the first lens group does not increase. As a result, the size of the optical system can be reduced.

  When the value goes below the upper limit of conditional expression (6), the zooming effect obtained by the first lens unit and the second lens unit can be increased, so that a high zoom ratio can be secured.

The variable power optical system of the present embodiment can satisfy the following conditional expression (7).
0.30 ≦ fG1 / ft ≦ 2.5 (7)
here,
fG1 is the focal length of the first lens group,
fw is the focal length of the variable power optical system at the telephoto end,
It is.

  The technical significance of conditional expression (7) is the same as the technical significance of conditional expression (6).

The variable power optical system of the present embodiment can satisfy the following conditional expression (8).
3.5 ≦ | fG1 / fG2 | ≦ 9.1 (8)
here,
fG1 is the focal length of the first lens group,
fG2 is the focal length of the second lens group,
It is.

  The technical significance of conditional expression (8) is the same as the technical significance of conditional expression (6).

The variable power optical system of the present embodiment can satisfy the following conditional expression (9).
1.0 ≦ fG3 / fw ≦ 8.0 (9)
here,
fG3 is the focal length of the third lens group,
fw is the focal length of the variable power optical system at the wide angle end,
It is.

  If the lower limit of conditional expression (9) is exceeded, the amount of spherical aberration generated mainly in the third lens group will decrease. Therefore, a small F-number can be secured at the wide-angle end. When falling below the upper limit value of conditional expression (9), the zooming effect of the third lens unit increases. As a result, a high zoom ratio can be secured.

The zoom optical system according to the present embodiment can satisfy the following conditional expression (10).
-14% <DTw <5% (10)
here,
DTw is the amount of distortion at the maximum angle of view at the wide-angle end, and is represented by the following equation:
DTw = (IHw1−IHw2) / IHw2 × 100 (%),
IHw1 is an actual image height when a light beam including a light ray having a maximum angle of view at the wide-angle end is formed on an image plane;
IHw2 is a paraxial image height when a light beam including a light ray having a maximum angle of view at the wide-angle end is formed on an image plane,
In each case, the image height when focusing on an object point at infinity,
It is.

  If the lower limit of conditional expression (10) is exceeded, the distortion of the image will be small, so that the subject can be photographed accurately. Alternatively, even if the distortion is corrected electrically, the image around the image is not greatly stretched. Therefore, it is possible to prevent the image from deteriorating in the peripheral portion of the image.

  When the value goes below the upper limit of conditional expression (10), the angle of view obtained in a state where no distortion occurs is widened. Therefore, a sufficient amount of information can be obtained at the wide-angle end.

  In the variable power optical system according to the present embodiment, the first lens group can include a negative lens and a positive meniscus lens having a convex surface facing the object side.

  By doing so, the zoom ratio can be increased, and the occurrence of chromatic aberration can be reduced by reflecting the zoom range widely. Further, since a positive meniscus lens having a convex surface facing the object side can be arranged in the first lens group, fluctuation of astigmatism during zooming can be reduced. As a result, stable imaging performance can be obtained over a wide zoom range.

  In the variable power optical system of the present embodiment, the first lens group can include a negative lens and two positive lenses.

  By doing so, it is possible to suppress the occurrence of spherical aberration in the first lens near the telephoto end. As a result, it is possible to increase the zoom ratio. Further, at least one of the positive lenses can be a positive meniscus lens having a convex surface facing the object side. By doing so, it is possible to suppress the occurrence of spherical aberration and reduce the fluctuation of astigmatism during zooming. As a result, stable imaging performance can be obtained over a wide zoom range.

  In the variable power optical system of the present embodiment, the two positive lenses can both be positive meniscus lenses with convex surfaces facing the object side.

  By doing so, fluctuations in astigmatism during zooming can be reduced. As a result, stable imaging performance can be obtained over a wide zoom range.

  In the variable power optical system of the present embodiment, one positive lens can be provided separately from the two positive lenses.

  By doing so, the refractive power of the first lens group can be increased. As a result, the overall length of the optical system can be reduced.

  In the variable power optical system of the present embodiment, the third lens group can include a positive lens and a negative lens.

  In order to increase the zoom ratio and decrease the F-number, it is preferable that spherical aberration can be corrected over a wide range of the wavelength range used. The third lens group can be located near the aperture stop. In this case, the third lens group is more involved in correcting spherical aberration. If a positive lens and a negative lens can be arranged in the third lens group, spherical aberration can be corrected.

  If the spherical aberration is corrected, even if the lens group is moved, it is possible to suppress the fluctuation of aberration due to the movement. Since the third lens group can be moved in a direction perpendicular to the optical axis, camera shake correction can be performed while maintaining high imaging performance.

  In the variable power optical system of the present embodiment, the third lens group can move so as to be located closer to the object side at the telephoto end than at the wide-angle end when focusing on an object at infinity.

  By doing so, the zooming effect of the third lens group can be increased. As a result, the zoom ratio can be increased.

  In the variable power optical system of the present embodiment, the third lens group can be fixed at the time of variable power.

  When the lens group is moved, the position at the time of stopping the lens group may vary due to the play of the moving mechanism. The third lens group has a large contribution to the variable power operation. Therefore, the third lens group is fixed at the time of zooming. By doing so, the deviation of the position of the third lens group from the designed position can be suppressed in a wide range of the variable power range. As a result, good imaging performance can be obtained in a wide zoom range. The third lens group may be fixed at the time of zooming, or may correspond to at least one of a focusing lens group and a camera shake correction lens group.

In the variable power optical system of the present embodiment, the third lens group can include a predetermined positive lens satisfying the following conditional expression (11).
63 ≦ νdG3P1 ≦ 100 (11)
here,
νdG3P1 is the Abbe number of a predetermined positive lens,
It is.

  If the lower limit of conditional expression (11) is exceeded, the occurrence of axial chromatic aberration in the third lens group will be small. Therefore, even if the zoom ratio is increased, good imaging performance can be secured over a wide zoom range. For example, even when a magnification ratio exceeding 10 times is to be obtained, good imaging performance can be secured in a wide range of the magnification range.

  In the variable power optical system of the present embodiment, the third lens group has a first positive lens and a cemented lens, and the cemented lens can be composed of a positive lens and a negative lens.

  The effect of correcting axial chromatic aberration and the effect of correcting lateral chromatic aberration can be enhanced by the cemented lens. In addition, the effect of correcting spherical aberration and the effect of correcting coma can be enhanced mainly at the cemented surface of the first positive lens and the cemented lens.

  In the variable power optical system of the present embodiment, the shape of the cemented lens can be a meniscus shape with the convex surface facing the object side.

  The effect of correcting axial chromatic aberration and the effect of correcting lateral chromatic aberration can be enhanced by the cemented lens. In addition, the effect of correcting spherical aberration and the effect of correcting coma can be enhanced mainly by the first positive lens and the cemented lens.

  A biconvex lens component having a positive refractive power can be arranged on the image side of the cemented lens. By doing so, the effect of correcting spherical aberration and the effect of correcting coma can be further enhanced. As a result, the zoom ratio can be increased and the F-number can be reduced.

  In the variable power optical system of the present embodiment, the relative position between the third lens unit and the fourth lens unit or the relative position between the fourth lens unit and the fifth lens unit is set between the wide-angle end and the telephoto end. Can change.

  By doing so, it is possible to correct the field curvature even when the zoom ratio is increased. For example, even if the zoom ratio exceeds 10 times, the field curvature can be corrected.

In the variable power optical system of the present embodiment, the fourth lens group can include a predetermined negative lens satisfying the following conditional expression (12).
51 ≦ νdG4N1 ≦ 100 (12)
here,
νdG4N1 is the Abbe number of the predetermined negative lens,
It is.

  If the lower limit of conditional expression (12) is exceeded, the fluctuation of chromatic aberration during focusing, that is, the fluctuation of axial chromatic aberration and the fluctuation of lateral chromatic aberration can be reduced. Therefore, good imaging performance can be obtained.

  As a method of suppressing the occurrence of chromatic aberration, there is a method of disposing a positive lens having a higher dispersion than a negative lens in the fourth lens group. However, if a positive lens is arranged in the fourth lens group, the weight of the fourth lens group may increase. By satisfying conditional expression (12), it is not necessary to arrange a high dispersion positive lens in the fourth lens group. In this case, it is possible to prevent the weight of the fourth lens group from increasing. Therefore, when focusing is performed by the fourth lens group, high-speed focusing becomes easy.

The variable power optical system of the present embodiment can satisfy the following conditional expression (13).
−1.5 ≦ SFG4 ≦ 1.8 (13)
here,
SFG4 is represented by the following equation:
SFG4 = (RG4f + RG4r) / (RG4f-RG4r),
RG4f is the radius of curvature of the lens surface of the fourth lens group located closest to the object,
RG4r is the radius of curvature of the lens surface of the fourth lens group located closest to the image,
It is.

  If the lower limit of conditional expression (13) is exceeded or the upper limit of conditional expression (13) is exceeded, the amount of occurrence of various aberrations in the fourth lens group decreases. For example, the occurrence of spherical aberration, astigmatism, and coma are reduced. Therefore, good imaging performance can be obtained.

  When conditional expression (13) is satisfied, when focusing or camera shake correction is performed by the fourth lens unit, spherical aberration and image plane deviation at a close distance are reduced. Even when the lens group is moved for camera shake correction, the asymmetry of the spherical aberration and the asymmetry of the astigmatism hardly increase. Therefore, good imaging performance can be obtained.

  In the variable power optical system of the present embodiment, the fourth lens group can be composed of one negative lens.

  The fourth lens group can be moved for focusing or for camera shake correction. By configuring the fourth lens group with one lens, the weight of the fourth lens group can be reduced. Then, the fourth lens group can be moved at high speed during focusing or when correcting camera shake. That is, it is possible to perform camera shake focusing with high tracking performance and camera shake correction with high tracking performance. In addition, the position of the lens group can be easily controlled. As a result, it is possible to improve the shooting accuracy and speed.

  In the variable power optical system of the present embodiment, the fifth lens group can be configured by a lens component having no air space.

  By doing so, the thickness of the fifth lens group in the optical axis direction can be reduced. In this case, the space on the object side and the space on the image side of the fifth lens group can be increased. Further, occurrence of higher-order chromatic aberration of magnification can be suppressed.

  In the variable power optical system of the present embodiment, the sixth lens group can include a negative lens and a positive lens.

  By doing so, the thickness of the sixth lens group in the optical axis direction can be reduced. In this case, the space on the object side of the sixth lens group can be increased.

  The negative lens and the positive lens in the sixth lens group can be cemented. By doing so, it is possible to suppress the occurrence of high-order coma aberration and high-order astigmatism.

  In the variable power optical system according to the present embodiment, the fifth lens group can be composed of one positive lens, and the sixth lens group can be composed of one negative lens and one positive lens.

  By doing so, the thickness of each of the fifth lens unit and the sixth lens unit in the optical axis direction can be reduced. In this case, the space on both sides of the fifth lens group can be increased. When the lens group located on the object side of the fifth lens group is moved along the optical axis, the moving space can be widened. As a result, a high zoom ratio can be secured.

  The fifth lens group can be moved for focusing or for camera shake correction. By configuring the fifth lens group with one lens, the weight of the fifth lens group can be reduced. Then, the fifth lens group can be moved at a high speed at the time of focusing or at the time of camera shake correction. That is, it is possible to perform camera shake focusing with high tracking performance and camera shake correction with high tracking performance. In addition, the position of the lens group can be easily controlled. As a result, it is possible to improve the shooting accuracy and speed.

The variable power optical system of the present embodiment can satisfy the following conditional expression (14).
0.5 ≦ fG5 / fG56w ≦ 2.5 (14)
here,
fG5 is the focal length of the fifth lens group,
fG56w is a composite focal length of the fifth lens unit and the sixth lens unit at the wide-angle end,
It is.

  If the lower limit of conditional expression (14) is exceeded, correction of astigmatism and correction of coma hardly become excessive. Therefore, good imaging performance can be obtained. When the value goes below the upper limit value of conditional expression (14), correction of astigmatism and correction of coma aberration hardly become insufficient. Therefore, good imaging performance can be obtained.

The variable power optical system of the present embodiment can satisfy the following conditional expression (15).
0.5 ≦ | fG5 / fG4 | ≦ 2.5 (15)
here,
fG4 is the focal length of the fourth lens group,
fG5 is the focal length of the fifth lens group,
It is.

  When the value exceeds the lower limit of conditional expression (15), correction of astigmatism and correction of coma hardly become excessive. Therefore, good imaging performance can be obtained. When the value goes below the upper limit of conditional expression (15), correction of astigmatism and correction of coma are unlikely to be insufficient. Therefore, good imaging performance can be obtained. Further, since the fluctuation of the image plane position at the time of focusing is reduced, good imaging performance is obtained.

The variable power optical system of the present embodiment can satisfy the following conditional expression (16).
0.026 ≦ DG56aw / fG56w ≦ 0.4 (16)
here,
DG56aw is an air gap between the fifth lens unit and the sixth lens unit at the wide-angle end,
fG56w is a composite focal length of the fifth lens unit and the sixth lens unit at the wide-angle end,
It is.

  If the lower limit of conditional expression (16) is exceeded, a sufficient astigmatism correction effect and coma correction effect will be obtained. When falling below an upper limit value of conditional expression (16), the thickness of the fifth lens unit in the optical axis direction does not increase. In this case, the movable space of the lens group that moves during zooming increases. Therefore, a high zoom ratio can be obtained.

The variable power optical system of the present embodiment can satisfy the following conditional expression (17).
0.1 ≦ DG56aw / fw ≦ 2.0 (17)
here,
DG56aw is an air gap between the fifth lens unit and the sixth lens unit at the wide-angle end,
fw is the focal length of the variable power optical system at the wide angle end,
It is.

  The technical significance of conditional expression (17) is the same as the technical significance of conditional expression (16).

The variable power optical system of the present embodiment can satisfy the following conditional expression (18).
0.3 ≦ | MGG4backw × (MGG4w−1) | ≦ 1.5 (18)
here,
MGG4w is the lateral magnification of the fourth lens group at the wide-angle end,
MGG4backw is a lateral magnification in a predetermined optical system at the wide-angle end,
The predetermined optical system is an optical system including all lenses located on the image side of the fourth lens group;
The lateral magnification is the lateral magnification when focusing on an object at infinity,
It is.

  When the value exceeds the lower limit of conditional expression (18), correction of astigmatism and correction of coma do not tend to be insufficient. Therefore, good imaging performance can be obtained. Further, when performing the camera shake correction by moving the fourth lens group, the camera shake correction sensitivity does not become too low. In this case, since the amount of movement of the fourth lens group does not increase, it is possible to improve the followability during camera shake correction.

  When the value goes below the upper limit of conditional expression (18), correction of astigmatism and correction of coma do not become excessive. Therefore, good imaging performance can be obtained.

In the variable power optical system of the present embodiment, the fifth lens group includes one positive lens, and can satisfy the following conditional expression (19).
52 ≦ νdG5P ≦ 100 (19)
here,
νdG5P is the Abbe number of the positive lens in the fifth lens group,
It is.

  If the lower limit of conditional expression (19) is exceeded, lateral chromatic aberration can be corrected. Therefore, good imaging performance can be obtained. When camera shake correction is performed by moving the fifth lens group, the occurrence of chromatic aberration does not increase. Therefore, good imaging performance can be obtained.

The variable power optical system of the present embodiment can satisfy the following conditional expression (20).
18.5 ≦ νdG6N ≦ 50 (20)
here,
νdG6N is the minimum Abbe number among the Abbe numbers of the negative lens in the sixth lens group,
It is.

  If the lower limit of conditional expression (20) is exceeded, generation of a secondary spectrum can be suppressed. In this case, chromatic aberration of magnification can be corrected. Therefore, good imaging performance can be obtained.

  In the zoom optical system according to the present embodiment, the aperture stop can be located between the second lens group and the third lens group.

  By doing so, the diameter of the first lens group and the diameter of the second lens group can both be reduced.

  In the variable power optical system of the present embodiment, the aperture stop can be fixed at the time of variable power.

  If the aperture stop is moved at the time of zooming, there may be a variation in the position when the movement of the aperture stop is stopped. When the stop position of the aperture stop varies, the value of the F-number changes. During zooming, if the aperture stop can be fixed, the position of the aperture stop will not vary. In this case, the value of the F number can be stabilized. As a result, even when the F-number is small, a stable light amount can be secured in a wide range of the variable power range.

  Further, electric means may be used for changing the aperture diameter of the aperture stop. As the electric means, for example, there is an electric wire for transmitting an electric signal. If the aperture stop is fixed at the time of zooming, the amount of movement of the aperture stop can be reduced, so that the change in the length of the electric wire can be reduced. As a result, electrical means having a highly durable structure can be realized.

The variable power optical system of the present embodiment can satisfy the following conditional expression (21).
2.3 ≦ fG1 / fG3 ≦ 7 (21)
here,
fG1 is the focal length of the first lens group,
fG3 is the focal length of the third lens group,
It is.

  If the lower limit of conditional expression (21) is exceeded, the zooming effect of the third lens unit will increase. Therefore, a high zoom ratio can be obtained. When falling below an upper limit value of conditional expression (21), it is possible to suppress occurrence of spherical aberration and coma in the third lens unit. Therefore, a small F number can be obtained.

The variable power optical system of the present embodiment can satisfy the following conditional expression (22).
0.5 ≦ | fG3 / fG4 | ≦ 2.0 (22)
here,
fG3 is the focal length of the third lens group,
fG4 is the focal length of the fourth lens group,
It is.

  If the lower limit of conditional expression (22) is exceeded, the effect of correcting the field curvature in the fourth lens group will be enhanced. Therefore, good imaging performance can be obtained in a wide range of the variable power range. When falling below the upper limit value of conditional expression (22), the amount of astigmatism generated in the fourth lens unit does not increase. For this reason, a state in which the image is blurred due to an assembly error hardly occurs.

The variable power optical system of the present embodiment can satisfy the following conditional expression (23).
0.25 ≦ fG2 / fG4 ≦ 1.5 (23)
here,
fG2 is the focal length of the second lens group,
fG4 is the focal length of the fourth lens group,
It is.

  If the lower limit of conditional expression (23) is exceeded, lateral chromatic aberration of the second lens group will not increase. Therefore, good imaging performance can be obtained. When falling below an upper limit value of conditional expression (23), the zooming effect of the second lens unit increases. Therefore, a high zoom ratio can be obtained.

The variable power optical system of the present embodiment can satisfy the following conditional expression (24).
0.25 ≦ | fG2 / fG3 | ≦ 1.5 (24)
here,
fG2 is the focal length of the second lens group,
fG3 is the focal length of the third lens group,
It is.

  The technical significance of conditional expression (24) is the same as the technical significance of conditional expression (23).

In the variable power optical system of the present embodiment, the first lens group includes, in order from the object side, a negative lens and a positive lens, and the positive lens of the first lens group is close to the negative lens of the first lens group. Thus, the following conditional expression (25) can be satisfied.
−0.1 ≦ fG1 × PG1NPa ≦ 0.27 (25)
here,
fG1 is the focal length of the first lens group,
PG1NPa is represented by the following equation:
PG1NPa = 1 / RG1NB-1 / RG1PF,
RG1NB is the radius of curvature of the image side lens surface of the negative lens in the first lens group,
RG1PF is the radius of curvature of the object-side lens surface of the positive lens in the first lens group,
It is.

  If the lower limit of conditional expression (25) is exceeded, the amount of astigmatism does not increase near the telephoto end. Therefore, good imaging performance can be obtained. When falling below the upper limit of conditional expression (25), the amount of spherical aberration generated near the telephoto end does not increase. Therefore, good imaging performance can be obtained.

  The negative lens of the first lens group and the positive lens of the first lens group can be cemented. By doing so, it is possible to reduce the error in the relative position when assembling the two lenses. Therefore, good imaging performance can be obtained.

The variable power optical system of the present embodiment can satisfy the following conditional expression (26).
2.5 ≦ fG5 / fw ≦ 15 (26)
here,
fG5 is the focal length of the fifth lens group,
fw is the focal length of the variable power optical system at the wide angle end,
It is.

  If the lower limit of conditional expression (26) is exceeded, the correction of astigmatism and the correction of coma hardly become excessive. Therefore, good imaging performance can be obtained even when the angle of view is increased. When the value goes below the upper limit of conditional expression (26), correction of astigmatism and correction of coma are less likely to be insufficient. Therefore, good imaging performance can be obtained.

The variable power optical system of the present embodiment can satisfy the following conditional expression (27).
-1.9≤SFG5≤0.95 (27)
here,
SFG5 is represented by the following equation:
SFG5 = (RG5f + RG5r) / (RG5f-RG5r),
RG5f is the radius of curvature of the lens surface of the fifth lens group located closest to the object,
RG5r is the radius of curvature of the lens surface of the fifth lens group located closest to the image,
It is.

  If the lower limit of conditional expression (27) is exceeded or the upper limit of conditional expression (27) is not exceeded, the amount of occurrence of various aberrations in the fifth lens group will not increase. For example, occurrence of spherical aberration, astigmatism, and coma do not increase. Therefore, good imaging performance can be obtained.

  Also, when focusing or camera shake correction is performed by the fifth lens group, spherical aberration and image plane deviation at a close distance increase. When the lens group is moved for camera shake correction, the asymmetry of spherical aberration and the asymmetry of astigmatism increase. Therefore, it is difficult to obtain good imaging performance.

  In the variable power optical system according to the present embodiment, at the time of variable power, the aperture stop can be moved or fixed in only one direction.

  During zooming, the aperture stop can move along the optical axis. If the direction of movement of the aperture stop is reversed during zooming, an error may occur in the position of the aperture stop with respect to the image plane. The position error occurs due to backlash in a moving mechanism using gears, for example. By changing the direction of movement of the aperture stop in only one direction during zooming, the position of the aperture stop can always be stabilized. The F-number changes with the magnification. When the position of the aperture stop can be stabilized, the position of the aperture stop can be matched or substantially matched with the position at the time of design. As a result, it is possible to reduce an error when the F number is changed.

  When the F-number is reduced, flare is likely to occur. If the position of the aperture stop can be fixed at the time of zooming, the error when the F-number is changed can be further reduced. As a result, the occurrence of flare can be reduced.

The variable power optical system of the present embodiment can satisfy the following conditional expression (28).
26.9 ° ≦ ΩHw / 2 ≦ 75 ° (28)
here,
ΩHw is the total horizontal angle of view at the wide-angle end,
It is.

  If the lower limit of conditional expression (28) is exceeded, a wide range can be imaged. Therefore, for example, in a surveillance camera, blind spots decrease. Videoconferencing cameras can shoot multiple people at once, even in a small room. When the value goes below the upper limit of conditional expression (28), the diameter of the first lens unit does not increase, so that the optical system can be downsized.

The variable power optical system of the present embodiment can satisfy the following conditional expression (29).
5.5 ≦ ft / fw ≦ 120 (29)
here,
ft is the focal length of the variable power optical system at the telephoto end,
fw is the focal length of the variable power optical system at the wide angle end,
It is.

  When the value exceeds the lower limit of conditional expression (29), a high-definition image is obtained. Therefore, for example, a surveillance camera can clearly capture a license plate of an automobile, a face of a person, and the like. When falling below the upper limit value of conditional expression (29), the overall length of the optical system can be shortened. As a result, the size of the optical system can be reduced.

The variable power optical system of the present embodiment can satisfy the following conditional expression (30).
0.6 ≦ FNOw ≦ 1.84 (30)
here,
FNOw is the F-number at the wide-angle end,
It is.

  If the lower limit of conditional expression (30) is exceeded, it is possible to suppress the occurrence of spherical aberration and the occurrence of astigmatism near the wide-angle end in each of the first lens group, the second lens group, and the third lens group. Even when good imaging performance is obtained, each lens group does not increase in size. Therefore, the size of the optical system can be reduced.

  When the value goes below the upper limit of conditional expression (30), sufficient brightness can be secured at the wide-angle end. Therefore, for example, with a surveillance camera, a good image can be obtained by monitoring when it is cloudy or at night.

The variable power optical system of the present embodiment can satisfy the following conditional expression (31).
0.7 ≦ FNOt ≦ 5.1 (31)
here,
FNOt is the F-number at the telephoto end,
It is.

  If the lower limit of conditional expression (31) is exceeded, the generation of spherical aberration and the generation of astigmatism near the telephoto end can be suppressed in each of the first lens group, the second lens group, and the third lens group. Even when good imaging performance is obtained, each lens group does not increase in size. Therefore, the size of the optical system can be reduced.

  When falling below the upper limit value of conditional expression (31), sufficient brightness can be secured at the telephoto end. Therefore, for example, with a surveillance camera, a good image can be obtained by monitoring when it is cloudy or at night.

The variable power optical system of the present embodiment can satisfy the following conditional expression (32).
−20 ≦ ft / fw + 143.9 × tan (ΩHw / 2) −121.88 ≦ 140 (32)
here,
fw is the focal length of the variable power optical system at the wide angle end,
ft is the focal length of the variable power optical system at the telephoto end,
ΩHw is the total horizontal angle of view at the wide-angle end,
It is.

  For example, a surveillance camera may check the field of view at the wide-angle end or magnify a predetermined area to check the inside of the predetermined area in detail. In order to obtain more detailed information, the zoom ratio may be increased.

  In a variable power optical system, the shooting area can be proportional to f × tan ω (f is the focal length and ω is the angle of view). Therefore, as the horizontal angle of view at the wide-angle end becomes narrower, the amount of information in the shooting area may decrease in proportion to the angle of view tan. That is, the reduction rate of the information amount is equal to or more than the change rate of the angle of view.

  When the horizontal angle of view at the wide-angle end is narrow, compensate for the amount of information by increasing the zoom ratio and narrowing the angle of view at the telephoto end compared to when the horizontal angle of view at the wide-angle end is wide. Becomes possible. If the lower limit of conditional expression (32) is exceeded, a sufficient amount of information will be obtained.

The variable power optical system of the present embodiment can satisfy the following conditional expression (33).
−1.5 ≦ ft / fw + 126.52 × tan (ΩHw / 2) −101.91 ≦ 140 (33)
here,
fw is the focal length of the variable power optical system at the wide angle end,
ft is the focal length of the variable power optical system at the telephoto end,
ΩHw is the total horizontal angle of view at the wide-angle end,
It is.

  The technical significance of conditional expression (33) is the same as the technical significance of conditional expression (32).

The variable power optical system of the present embodiment can satisfy the following conditional expression (34).
−2.0 ≦ ft / fw + 13.38 × tan (ΩHw / 2) −21.0 ≦ 140 (34)
here,
fw is the focal length of the variable power optical system at the wide angle end,
ft is the focal length of the variable power optical system at the telephoto end,
ΩHw is the total horizontal angle of view at the wide-angle end,
It is.

  The technical significance of conditional expression (34) is the same as the technical significance of conditional expression (32).

The variable power optical system of the present embodiment can satisfy the following conditional expression (35).
-3 ≦ ft / fw + 80.72 × tan (ΩHw / 2) −62.0 ≦ 140 (35)
here,
fw is the focal length of the variable power optical system at the wide angle end,
ft is the focal length of the variable power optical system at the telephoto end,
ΩHw is the total horizontal angle of view at the wide-angle end,
It is.

  The technical significance of conditional expression (35) is the same as the technical significance of conditional expression (32).

  The variable power optical system according to the present embodiment can include a positive lens and a negative lens between the fifth lens group and the image plane.

  If the refractive power of each lens group can be increased, the zooming effect can be increased. If the zooming action can be increased, the overall length of the optical system can be reduced and the diameter of the optical system can be reduced. However, when the zooming action becomes large, it becomes difficult to secure good imaging performance over a wide zooming range when securing a small F-number.

  The second lens group can contribute to ensuring a wide angle of view at the wide-angle end. When the zooming action can be increased, chromatic aberration of magnification easily occurs in the second lens group. Even if chromatic aberration of magnification occurs in the second lens group, if the occurrence of chromatic aberration of magnification in the entire optical system can be suppressed, the angle of view at the wide-angle end can be made wider, and the miniaturization of the optical system and the securing of a small F-number can be realized. it can.

  Between the fifth lens group and the image plane, the separation state of the on-axis light beam and the off-axis light beam at the wide-angle end is similar to that of the second lens group. If a lens can be arranged between the fifth lens group and the image plane, lateral chromatic aberration can be generated by this lens. At this time, the direction in which chromatic aberration of magnification occurs in this lens group can be reversed from the direction in which chromatic aberration of magnification occurs in the second lens group.

  A positive lens and a negative lens can be arranged between the fifth lens group and the image plane. Using the negative lens and the positive lens, the direction in which the chromatic aberration of magnification occurs in the positive lens and the negative lens can be reversed from the direction in which the chromatic aberration of magnification occurs in the second lens group.

  As described above, since the positive lens and the negative lens can have a function of correcting magnification aberration, chromatic aberration of magnification generated in the second lens group can be corrected by the positive lens and the negative lens. As a result, it is possible to correct the chromatic aberration of magnification and to increase the magnification from a wide angle range.

  However, if the chromatic aberration of magnification is mainly corrected, astigmatism and coma may occur. Therefore, if only the chromatic aberration of magnification is mainly suppressed, the imaging performance may be adversely affected. In a portion close to the fourth lens group, the ability to correct aberration is high in the range from the fifth lens group to the image plane. A lens component having a positive refractive power can be arranged in a portion closest to the fourth lens group. By doing so, it is possible to suppress the occurrence of other than the chromatic aberration of magnification in the lens component.

The variable power optical system of the present embodiment can satisfy the following conditional expression (36).
0.04 ≦ ΔG1 / LTLw ≦ 0.33 (36)
here,
ΣG1 is the thickness of the first lens group,
LTLw is the total length of the variable power optical system at the wide-angle end,
It is.

  If the lower limit of conditional expression (36) is exceeded, the refractive power of the first lens group can be sufficiently ensured. Therefore, the total length of the optical system can be reduced. When the total length of the optical system is shortened by falling below the upper limit of conditional expression (36), it is possible to secure a space for moving the second lens unit during zooming. Therefore, a high zoom ratio can be secured while securing a wide angle of view on the wide-angle side.

  In the variable power optical system of the present embodiment, the fourth lens group and the fifth lens group can move together during focusing.

  By doing so, the imaging performance when focusing on an object at a close distance can be improved.

The variable power optical system of the present embodiment can satisfy the following conditional expression (37).
0.01 ≦ | fG5 / fG6 | ≦ 3.0 (37)
here,
fG5 is the focal length of the fifth lens group,
fG6 is the focal length of the sixth lens group,
It is.

  Between the fifth lens group and the sixth lens group, an astigmatism correcting action and a magnification chromatic aberration correcting action occur. When the value exceeds the lower limit of conditional expression (36) or falls below the upper limit of conditional expression (36), the effect of correcting astigmatism and the effect of correcting chromatic aberration of magnification increase. Therefore, good imaging performance can be obtained.

  The imaging apparatus according to the present embodiment includes an optical system, and an imaging device that has an imaging surface and converts an image formed on the imaging surface by the optical system into an electric signal. It is a double optical system.

  An imaging device capable of obtaining a high-quality image can be provided.

The imaging apparatus according to the present embodiment can satisfy the following conditional expression (38).
2.5mm ≦ Rimg ≦ 40mm (38)
here,
Rimg is the radius of the image circle in the image sensor,
It is.

  The optical system used for the surveillance camera can have a high resolution in order to secure a sufficient amount of information. The high resolution is, for example, a high-definition resolution or a resolution that exceeds the high-definition resolution. In order to obtain such a resolution, the number of pixels of the image sensor is preferably, for example, at least 2.5 million pixels or more, 3 million images or more, or 8 million pixels.

  When the value exceeds the lower limit of conditional expression (30), the pixel pitch does not become too small even when a high resolution is secured. In this case, the sensitivity of the imaging device can be kept high. Therefore, a good image can be obtained.

  Examples of the imaging device include a digital camera, a video camera, a surveillance camera, and a camera of a video conference system.

  There are, for example, two photographing needs in digital cameras and video cameras. The first need for photography is to photograph a large building or to take a commemorative photograph against a vast background. A second need for photographing is a need to use a single photographing lens to perform photographing from a wide range to magnified photographing of a subject.

  In order to satisfy the first shooting need, the angle of view of the optical system may be made wider. In order to satisfy the second photographing need, the zoom ratio of the optical system may be increased. As an optical system that satisfies the two photographing needs, for example, there is a zoom optical system having a half angle of view of 33 degrees or more and a zoom ratio of 5 times or more. Since the variable power optical system having such specifications can be used in various photographing scenes, it can be said that the variable power optical system is easy to use.

  As a need for a surveillance camera, it may be possible to perform monitoring over a wider area or to perform monitoring at a higher magnification. For example, monitoring at a higher magnification makes it easy to specify a number on a license plate or a person.

  Further, as needs in the video conference system, it is possible that the state of the entire conference room can be grasped or the state of a part of the conference room can be grasped in detail.

  For this reason, in the imaging apparatus, the need for an optical system that has a wide angle of view at the wide-angle end and a zoom ratio of more than 5 may be high.

  In a digital camera or a video camera, mobility may be important. Here, the mobility refers to, for example, ease of carrying, stability at the time of hand-held shooting, high-speed focus speed, and the like. The optical system may be small and lightweight in order to improve the mobility of the device. Further, in a surveillance camera, a place where the surveillance camera is installed may be limited, and thus the optical system may be required to be reduced in size and diameter.

  Further, when the image pickup apparatus vibrates due to camera shake, if the shooting speed is low, the image may be unclear due to the influence of the vibration. In order to obtain a clear image, the F-number may be reduced.

The variable magnification optical system according to the present embodiment can be mainly used for an optical system of an imaging device using an electronic imaging device. In this case, the half angle of view can be 36 degrees or more. The half angle of view may be 40 degrees or more, or even 42 degrees or more. The correspondence between the half angle of view and the focal length is as follows.
Half angle of view Focal length 40 degrees or more 25.7 mm or less 42 degrees or more and 24 mm or less

  The variable power optical system of the present embodiment can secure a wide angle of view and a small F-number at the wide-angle end, and can satisfactorily correct various aberrations. Furthermore, the variable power optical system of the present embodiment is excellent in mobility and freedom of installation, and the optical system is reduced in size and diameter. According to the variable power optical system of the present embodiment, it is possible to provide an imaging optical system that is effective for stable shooting and quick shooting without missing shooting opportunities.

  The above-described variable power optical system and optical device can simultaneously satisfy a plurality of configurations. By doing so, it is possible to obtain a good zoom optical system and optical device. The combination of the configurations is arbitrary. In addition, for each conditional expression, only the upper limit or the lower limit of the numerical range of the conditional expression that is more limited can be limited.

  At least one of conditional expressions (1-1) to (38) can be combined with the basic configuration of the variable power optical system according to the present embodiment. In this combination, it is possible not to include the conditional expression (1).

For each conditional expression, the lower limit or the upper limit can be changed as follows.
The conditional expressions (1) and (1-1) are as follows.
The lower limit is 0.013, 0.014, 0.02, 0.023, 0.025, 0.034, 0.035, 0.04, 0.045, 0.046, 0.05, 0.06 Can be either.
The upper limit can be any of 3.8, 2.6, 1.4, 0.6, 0.5, 0.3, 0.25, 0.17.
The conditional expression (2) is as follows.
The upper limit can be any of 0.11, 0.1, 0.065, 0.03.
The conditional expression (3) is as follows.
The lower limit can be any of 1.4, 1.5, 1.52, 1.6, 1.8, 2.0, 2.2, 2.5.
The upper limit can be any of 4.3, 4.2, 4.1, 4.0, 3.8, 3.6, 3.5, 3.2, 2.76.
Conditional expression (4) is as follows.
The lower limit can be any of -0.06, -0.059, -0.053, -0.05, -0.048, -0.04, -0.02.
The upper limit can be any of 0.15, 0.11, 0.08, 0.074, 0.05, and 0.035.
The conditional expression (5) is as follows.
The lower limit can be any of -0.089, -0.068, -0.048, and -0.03.
The upper limit can be any of 0.083, 0.055, 0.05, and 0.028.
The conditional expression (6) is as follows.
The lower limit can be any of 5.6, 6.0, 7.2, 8.0, 8.8, 10, 10.45.
The upper limit can be any one of 31, 30, 27, 25, 22, and 18.
Conditional expression (7) is as follows.
The lower limit can be any of 0.33, 0.36, 0.38, 0.41, 0.50, 0.60, 0.70, 0.80.
The upper limit can be any of 2.3, 2.2, 2.0, 1.9, 1.8, 1.6, 1.29.
Conditional expression (8) is as follows.
The lower limit can be any of 4.0, 4.5, 4.6, 5.1, 5.6.
The upper limit can be 8.7, 8.5, 8.4, 8.0, 7.4, or 6.9.
The conditional expression (9) is as follows.
The lower limit can be any of 1.5, 1.9, 2.0, 2.4, 2.5, 2.8.
The upper limit can be any of 7.5, 7.4, 7.0, 6.7, 6.5, 6.1, 5.5.
The conditional expression (10) is as follows (unit is “%”).
The lower limit can be any of -12.5, -11.0, -9.5, and -8.0.
The upper limit can be any of 2.7, 0.49, -1.8, and -4.1.
The conditional expression (11) is as follows.
The lower limit can be any of 64, 65, 66, 67, 69, 70, 74, 80.
The upper limit can be any of 95, 91, 86, 82.
The conditional expression (12) is as follows.
The lower limit can be any of 52, 53, 54, 55.52, 56, 59, 63, 65.
The upper limit can be any of 95, 91, 86, 82.
The conditional expression (13) is as follows.
The lower limit can be any of -1.1, -1.0, -0.8, -0.71, -0.60, -0.50, -0.32, and 0.07.
The upper limit can be any of 1.5, 1.3, 1.2, 1.1, 1.0, 0.90, 0.80, 0.70.
The conditional expression (14) is as follows.
The lower limit can be any of 0.59, 0.6, 0.68, 0.7, 0.77, 0.8, 0.86.
The upper limit can be any of 2.2, 2.0, 1.8, 1.7, 1.6, 1.44.
The conditional expression (15) is as follows.
The lower limit can be any of 0.58, 0.6, 0.66, 0.7, 0.74, 0.83, 0.9.
The upper limit can be any of 2.2, 2.0, 1.9, 1.8, 1.6, 1.34.
The conditional expression (16) is as follows.
The lower limit can be any of 0.03, 0.04, 0.05, 0.06, 0.07.
The upper limit can be any of 0.4, 0.35, 0.3, 0.28, 0.24.
The conditional expression (17) is as follows.
The lower limit can be any of 0.12, 0.13, 0.15, 0.18, 0.20.
The upper limit can be any of 1.7, 1.5, 1.2, and 0.97.
The conditional expression (18) is as follows.
The lower limit can be any of 0.35, 0.4, 0.42, 0.5, 0.55, 0.67, 0.79.
The upper limit can be any of 1.4, 1.3, 1.2, 1.1, 1.0, 0.94.
The conditional expression (19) is as follows.
The lower limit can be any of 54, 55, 56, 58, 59, 63, 67.
The upper limit can be any of 95, 91, 86, 82.
The conditional expression (20) is as follows.
The lower limit can be any of 19, 20, 23, 25.
The upper limit can be any of 47, 45, 42, 40.
The conditional expression (21) is as follows.
The lower limit can be any of 2.5, 2.6, 2.8, 3.0, 3.30.
The upper limit can be any of 6.5, 6.2, 5.5, 5.4, 4.6, 3.83.
The conditional expression (22) is as follows.
The lower limit can be any of 0.56, 0.63, 0.69, 0.7, 0.75, 0.85.
The upper limit can be any of 1.8, 1.7, 1.6, 1.5, 1.4, 1.26.
The conditional expression (23) is as follows.
The lower limit can be any of 0.2, 0.29, 0.33, 0.35, 0.37, 0.40, 0.53.
The upper limit can be any of 1.6, 1.3, 1.2, 1.1, 1.0, 0.9.
The conditional expression (24) is as follows.
The lower limit can be any of 0.31, 0.35, 0.38, 0.4, 0.44, 0.45, 0.51.
The upper limit can be any of 1.3, 1.2, 1.1, 1.0, 0.9, 0.65.
The conditional expression (25) is as follows.
The lower limit can be any of -0.08, -0.05, -0.03, -0.01, 0.00.
The upper limit can be any of 0.2, 0.15, 0.1.
The conditional expression (26) is as follows.
The lower limit can be any of 2.70, 2.89, 3.0, 3.09, 3.1, 3.2, 3.28, 4.0.
The upper limit can be any of 12.7, 12, 10, 10.4, 8.1, 8.0, 7.0, 5.80.
The conditional expression (27) is as follows.
The lower limit can be any of -1.7, -1.5, -1.4, -1.2, -0.98, -0.97, -0.8, -0.7. .
The upper limit can be any of 0.8, 0.7, 0.6, 0.5, 0.4, 0.3, -0.3, and 0.27.
The conditional expression (28) is as follows (unit is “° (degree)”).
The lower limit can be any of 28.8, 30.74, 32.65, 34, 34.57, 37, 39, 41.
The upper limit can be any of 67, 59, 51, 43.05.
The conditional expression (29) is as follows.
The lower limit can be any of 6.9, 7.0, 8.3, 9.5, 9.8, 11.1, 12, 13.5, 14, 21.
The upper limit can be any of 100, 81, 80, 63, 60, 45, 44, 40, 35, 30, 26.
The conditional expression (30) is as follows.
The lower limit can be any of 0.65, 0.76, 0.8, 0.9, 1.1, 1.26.
The upper limit can be any of 1.8, 1.79, 1.78, 1.75, 1.70, 1.65.
The conditional expression (31) is as follows.
The lower limit can be any of 0.8, 1.0, 1.2, 1.3, 1.7, 1.97.
The upper limit can be any of 5.0, 4.9, 4.8, 4.7, 4.6, 4.3, 4.0, 3.5, 4.48.
The conditional expression (32) is as follows.
The lower limit is -14.4, -10, -8.7, -6.0, -5.0, -4.0, -3.1, 0.0, 1.0, 2.6, 4. 5 can be used.
The upper limit can be any of 112, 100, 83, 75, 60, 55, 50, 45, 40, 27.
The conditional expression (33) is as follows.
Lower limit value is any of 1.5, 3.0, 4.0, 4.5, 5.0, 6.0, 7.0, 7.5, 8.0, 9.0, 10.6 can do.
The upper limit can be any of 113, 100, 85, 75, 60, 58, 50, 45, 40, 30.
The conditional expression (34) is as follows.
The lower limit can be any of -1.2, -0.4, 0.4, 1.1, 2.0, 3.5.
The upper limit can be any of 120, 108, 90, 77, 70, 60, 50, 45, 40, 14.
The conditional expression (35) is as follows.
The lower limit can be any of 1.6, 4, 6.1, 8, 9, 10.7, 12, 14, 15.3.
The upper limit can be any of 112, 100, 84, 75, 60, 56, 50, 45, 40, 28.
The conditional expression (36) is as follows.
The lower limit can be any of 0.050, 0.059, 0.069, 0.08.
The upper limit can be any of 0.3, 0.25, 0.2, 0.15.
The conditional expression (37) is as follows.
The lower limit can be any of 0.016, 0.022, 0.028, and 0.03.
The upper limit can be any of 2.4, 1.9, 1.3, 0.70.
The conditional expression (38) is as follows (the unit is “mm”).
The lower limit can be any of 2.7, 2.90, 3.0, 3.1, 3.30, 3.4, 3.5, 3.8, 4.1.
The upper limit can be any of 31, 22, 13, 4.00.

  Hereinafter, embodiments of the variable power optical system will be described in detail with reference to the drawings. The present invention is not limited by the embodiment.

  A lens cross-sectional view of each embodiment will be described. (A) is a lens cross-sectional view at a wide-angle end, (b) is a lens cross-sectional view at an intermediate focal length state, and (c) is a lens cross-sectional view at a telephoto end.

  The aberration diagrams of each embodiment will be described. (A) is spherical aberration (SA) at the wide-angle end, (b) is astigmatism (AS) at the wide-angle end, (c) is distortion (DT) at the wide-angle end, and (d) is chromatic aberration of magnification at the wide-angle end ( CC).

  (E) is spherical aberration (SA) in the intermediate focal length state, (f) is astigmatism (AS) in the intermediate focal length state, (g) is distortion (DT) in the intermediate focal length state, (h) ) Shows the chromatic aberration of magnification (CC) in the intermediate focal length state.

  (I) is spherical aberration (SA) at the telephoto end, (j) is astigmatism (AS) at the telephoto end, (k) is distortion (DT) at the telephoto end, and (l) is magnification at the telephoto end. Chromatic aberration (CC) is shown.

  Both the lens cross-sectional view and the aberration diagram are diagrams when an object at infinity is in focus.

  The first lens group is G1, the second lens group is G2, the third lens group is G3, the fourth lens group is G4, the fifth lens group is G5, the sixth lens group is G6, and the aperture stop (brightness stop) is S and the image plane (imaging plane) are indicated by I. Further, a cover glass C of the image sensor can be arranged between the sixth lens group G6 and the image plane I.

  The variable power optical system according to the first embodiment includes, in order from the object side, a first lens group G1 having a positive refractive power, a second lens group G2 having a negative refractive power, and a third lens having a positive refractive power. The zoom lens includes a group G3, a fourth lens group G4 having a negative refractive power, a fifth lens group G5 having a positive refractive power, and a sixth lens group G6 having a positive refractive power. The aperture stop S is arranged between the second lens group G2 and the third lens group G3.

  The first lens group G1 includes a negative meniscus lens L1 having a convex surface facing the object side, a positive meniscus lens L2 having a convex surface facing the object side, and a positive meniscus lens L3 having a convex surface facing the object side. I have. Here, the negative meniscus lens L1 and the positive meniscus lens L2 are joined.

  The second lens group G2 includes a negative meniscus lens L4 having a convex surface facing the object side, a biconcave negative lens L5, and a biconvex positive lens L6.

  The third lens group G3 includes a biconvex positive lens L7, a negative meniscus lens L8 having a convex surface facing the object side, and a biconvex positive lens L9. Here, the negative meniscus lens L8 and the biconvex positive lens L9 are joined.

  The fourth lens group G4 includes a biconcave negative lens L10.

  The fifth lens group G5 includes a biconvex positive lens L11.

  The sixth lens group G6 includes a biconcave negative lens L12 and a biconvex positive lens L13. Here, the biconcave negative lens L12 and the biconvex positive lens L13 are joined.

  At the time of zooming, the first lens group G1 is fixed, the second lens group G2 moves to the image side, the third lens group G3 moves to the object side, the fourth lens group G4 moves to the image side, The fifth lens group G5 moves to the image side, and the sixth lens group G6 is fixed. The aperture stop S is fixed.

  At the time of focusing, the fifth lens group G5 moves along the optical axis, and at the time of camera shake correction, the fourth lens group G4 moves in a direction perpendicular to the optical axis.

  The aspherical surface is provided on a total of eight surfaces of both sides of the biconcave negative lens L5, both sides of the biconvex positive lens L7, both sides of the biconcave negative lens L10, and both sides of the biconvex positive lens L11. Have been.

  The variable power optical system according to the second embodiment includes, in order from the object side, a first lens group G1 having a positive refractive power, a second lens group G2 having a negative refractive power, and a third lens having a positive refractive power. The zoom lens includes a group G3, a fourth lens group G4 having a negative refractive power, a fifth lens group G5 having a positive refractive power, and a sixth lens group G6 having a positive refractive power. The aperture stop S is arranged between the second lens group G2 and the third lens group G3.

  The first lens group G1 includes a negative meniscus lens L1 having a convex surface facing the object side, a positive meniscus lens L2 having a convex surface facing the object side, and a positive meniscus lens L3 having a convex surface facing the object side. I have. Here, the negative meniscus lens L1 and the positive meniscus lens L2 are joined.

  The second lens group G2 includes a negative meniscus lens L4 having a convex surface facing the object side, a biconcave negative lens L5, and a biconvex positive lens L6.

  The third lens group G3 includes a biconvex positive lens L7, a negative meniscus lens L8 having a convex surface facing the object side, and a biconvex positive lens L9. Here, the negative meniscus lens L8 and the biconvex positive lens L9 are joined.

  The fourth lens group G4 includes a biconcave negative lens L10.

  The fifth lens group G5 includes a biconvex positive lens L11.

  The sixth lens group G6 includes a negative meniscus lens L12 having a convex surface facing the object side, and a positive meniscus lens L13 having a convex surface facing the object side. Here, the negative meniscus lens L12 and the positive meniscus lens L13 are joined.

  During zooming, the first lens group G1 is fixed, the second lens group G2 moves to the image side, the third lens group G3 moves to the object side, and the fourth lens group G4, the fifth lens group G5, and the The six-lens group G6 is fixed. The aperture stop S is fixed.

  At the time of focusing, the fifth lens group G5 moves along the optical axis, and at the time of camera shake correction, the fourth lens group G4 moves in a direction perpendicular to the optical axis.

  The aspherical surface is provided on a total of eight surfaces of both sides of the biconcave negative lens L5, both sides of the biconvex positive lens L7, both sides of the biconcave negative lens L10, and both sides of the biconvex positive lens L11. Have been.

  The variable power optical system according to the third embodiment includes, in order from the object side, a first lens group G1 having a positive refractive power, a second lens group G2 having a negative refractive power, and a third lens having a positive refractive power. The zoom lens includes a group G3, a fourth lens group G4 having a negative refractive power, a fifth lens group G5 having a positive refractive power, and a sixth lens group G6 having a positive refractive power. The aperture stop S is arranged between the second lens group G2 and the third lens group G3.

  The first lens group G1 includes a negative meniscus lens L1 having a convex surface facing the object side, a positive meniscus lens L2 having a convex surface facing the object side, and a positive meniscus lens L3 having a convex surface facing the object side. I have. Here, the negative meniscus lens L1 and the positive meniscus lens L2 are joined.

  The second lens group G2 includes a negative meniscus lens L4 having a convex surface facing the object side, a biconcave negative lens L5, and a biconvex positive lens L6.

  The third lens group G3 includes a biconvex positive lens L7, a negative meniscus lens L8 having a convex surface facing the object side, and a biconvex positive lens L9. Here, the negative meniscus lens L8 and the biconvex positive lens L9 are joined.

  The fourth lens group G4 includes a biconcave negative lens L10.

  The fifth lens group G5 includes a biconvex positive lens L11.

  The sixth lens group G6 includes a negative meniscus lens L12 having a convex surface facing the object side, and a biconvex positive lens L13. Here, the negative meniscus lens L12 and the biconvex positive lens L13 are joined.

  During zooming, the first lens group G1 is fixed, the second lens group G2 moves to the image side, the third lens group G3 moves to the object side, and the fourth lens group G4 moves to the object side. Moving to the image side, the fifth lens group G5 and the sixth lens group G6 are fixed. The aperture stop S is fixed.

  At the time of focusing, the fifth lens group G5 moves along the optical axis, and at the time of camera shake correction, the fourth lens group G4 moves in a direction perpendicular to the optical axis.

  The aspherical surface is provided on a total of eight surfaces of both sides of the biconcave negative lens L5, both sides of the biconvex positive lens L7, both sides of the biconcave negative lens L10, and both sides of the biconvex positive lens L11. Have been.

  The variable power optical system of Example 4 includes, in order from the object side, a first lens group G1 having a positive refractive power, a second lens group G2 having a negative refractive power, and a third lens having a positive refractive power. The zoom lens includes a group G3, a fourth lens group G4 having a negative refractive power, a fifth lens group G5 having a positive refractive power, and a sixth lens group G6 having a positive refractive power. The aperture stop S is arranged between the second lens group G2 and the third lens group G3.

  The first lens group G1 includes a negative meniscus lens L1 having a convex surface facing the object side, a positive meniscus lens L2 having a convex surface facing the object side, and a positive meniscus lens L3 having a convex surface facing the object side. I have. Here, the negative meniscus lens L1 and the positive meniscus lens L2 are joined.

  The second lens group G2 includes a negative meniscus lens L4 having a convex surface facing the object side, a biconcave negative lens L5, and a biconvex positive lens L6.

  The third lens group G3 includes a biconvex positive lens L7, a negative meniscus lens L8 having a convex surface facing the object side, and a biconvex positive lens L9. Here, the negative meniscus lens L8 and the biconvex positive lens L9 are joined.

  The fourth lens group G4 includes a biconcave negative lens L10.

  The fifth lens group G5 includes a biconvex positive lens L11.

  The sixth lens group G6 includes a negative meniscus lens L12 having a convex surface facing the object side, and a biconvex positive lens L13. Here, the negative meniscus lens L12 and the biconvex positive lens L13 are joined.

  During zooming, the first lens group G1 moves to the image side and then moves to the object side, the second lens group G2 moves to the image side, the third lens group G3 moves to the object side, and the fourth lens group The group G4, the fifth lens group G5, and the sixth lens group G6 are fixed. The aperture stop S is fixed.

  At the time of focusing, the fifth lens group G5 moves along the optical axis, and at the time of camera shake correction, the fourth lens group G4 moves in a direction perpendicular to the optical axis.

  The aspherical surface is provided on a total of eight surfaces of both sides of the biconcave negative lens L5, both sides of the biconvex positive lens L7, both sides of the biconcave negative lens L10, and both sides of the biconvex positive lens L11. Have been.

  The variable power optical system of Example 5 includes, in order from the object side, a first lens group G1 having a positive refractive power, a second lens group G2 having a negative refractive power, and a third lens having a positive refractive power. The zoom lens includes a group G3, a fourth lens group G4 having a negative refractive power, a fifth lens group G5 having a positive refractive power, and a sixth lens group G6 having a positive refractive power. The aperture stop S is arranged between the second lens group G2 and the third lens group G3.

  The first lens group G1 includes a negative meniscus lens L1 having a convex surface facing the object side, a positive meniscus lens L2 having a convex surface facing the object side, and a positive meniscus lens L3 having a convex surface facing the object side. I have. Here, the negative meniscus lens L1 and the positive meniscus lens L2 are joined.

  The second lens group G2 includes a negative meniscus lens L4 having a convex surface facing the object side, a biconcave negative lens L5, and a biconvex positive lens L6.

  The third lens group G3 includes a biconvex positive lens L7, a negative meniscus lens L8 having a convex surface facing the object side, and a biconvex positive lens L9. Here, the negative meniscus lens L8 and the biconvex positive lens L9 are joined.

  The fourth lens group G4 includes a biconcave negative lens L10.

  The fifth lens group G5 includes a biconvex positive lens L11 and a negative meniscus lens L12 having a convex surface facing the image side. Here, the biconvex positive lens L11 and the negative meniscus lens L12 are joined.

  The sixth lens group G6 includes a negative meniscus lens L13 having a convex surface facing the object side, and a biconvex positive lens L14. Here, the negative meniscus lens L13 and the biconvex positive lens L14 are joined.

  During zooming, the first lens group G1 is fixed, the second lens group G2 moves to the image side, the third lens group G3 moves to the object side, and the fourth lens group G4 moves to the object side. Moving to the image side, the fifth lens group G5 and the sixth lens group G6 are fixed. The aperture stop S is fixed.

  At the time of focusing, the fifth lens group G5 moves along the optical axis, and at the time of camera shake correction, the fourth lens group G4 or the fifth lens group G5 moves in a direction perpendicular to the optical axis.

  The aspherical surface is provided on a total of seven surfaces including both sides of the biconcave negative lens L5, both sides of the biconvex positive lens L7, both sides of the biconcave negative lens L10, and the object side surface of the biconvex positive lens L11. Have been.

  The zoom optical system according to Example 6 includes, in order from the object side, a first lens group G1 having a positive refractive power, a second lens group G2 having a negative refractive power, and a third lens having a positive refractive power. The zoom lens includes a group G3, a fourth lens group G4 having a negative refractive power, a fifth lens group G5 having a positive refractive power, and a sixth lens group G6 having a negative refractive power. The aperture stop S is arranged between the second lens group G2 and the third lens group G3.

  The first lens group G1 includes a negative meniscus lens L1 having a convex surface facing the object side, a biconvex positive lens L2, a positive meniscus lens L3 having a convex surface facing the object side, and a positive meniscus lens having a convex surface facing the object side. L4. Here, the negative meniscus lens L1 and the biconvex positive lens L2 are joined.

  The second lens group G2 includes a negative meniscus lens L5 having a convex surface facing the object side, a biconcave negative lens L6, and a biconvex positive lens L7.

  The third lens group G3 includes a biconvex positive lens L8, a negative meniscus lens L9 having a convex surface facing the object side, and a biconvex positive lens L10. Here, the negative meniscus lens L9 and the biconvex positive lens L10 are joined.

  The fourth lens group G4 includes a biconcave negative lens L11.

  The fifth lens group G5 includes a biconvex positive lens L12.

  The sixth lens group G6 includes a biconcave negative lens L13 and a biconvex positive lens L14. Here, the biconcave negative lens 13 and the biconvex positive lens L14 are joined.

  During zooming, the first lens group G1 is fixed, the second lens group G2 moves to the image side, the third lens group and the fourth lens group G4 are fixed, and the fifth lens group G5 moves to the object side. Thereafter, the lens moves to the image side, and the sixth lens group G6 is fixed. The aperture stop S is fixed.

  At the time of focusing, the fifth lens group G5 moves along the optical axis, and at the time of camera shake correction, the fourth lens group G4 moves in a direction perpendicular to the optical axis.

  The aspheric surfaces are provided on a total of eight surfaces including both sides of the negative meniscus lens L5, both sides of the biconvex positive lens L8, both sides of the biconcave negative lens L11, and both sides of the biconvex positive lens L12. ing.

  Table 1 shows the results obtained by dividing the lens groups based on the two criteria. The lens group can be divided depending on whether or not the lens moves relatively differently with respect to the adjacent lens. The relative movement with respect to the adjacent lens differs during zooming, when focusing, or when correcting camera shake. When classified based on the relative movement during zooming, when classified based on the relative movement during focusing, and when classified based on the relative movement during camera shake correction And the lens groups are different.

For example, in the second embodiment, when the classification is performed based on the relative movement at the time of zooming, the following is performed.
First lens group: L1, L2, L3
Second lens group: L4, L5, L6
Third lens group: L7, L8, L9
Fourth lens group: L10, L11, L12, L13

When the classification is performed based on the relative movement at the time of focusing, it is as follows.
First lens group: L1, L2, L3, L4, L5, L6, L7, L8, L9
Second lens group: L10
Third lens group: L11, L12, L13

When the classification is performed based on the relative movement at the time of camera shake correction, the following is performed.
First lens group: L1, L2, L3, L4, L5, L6, L7, L8, L9, L10
Second lens group: L11
Third lens group: L12, L13

  As described above, when the image is classified based on the relative motion during zooming, when the image is classified based on the relative motion during focusing, and when the image is classified based on the relative motion during camera shake correction. In this case, the number of lens groups and the number of lenses included in one lens group are different.

Assuming that a group of lenses composed of the smallest number of lenses is one lens group, the following is obtained based on changes in the intervals at the time of zooming, focusing, and correction of camera shake.
First lens group: L1, L2, L3
Second lens group: L4, L5, L6
Third lens group: L7, L8, L9
Fourth lens group: L10
Fifth lens group: L11
Sixth lens group: L12, L13

In Table 1, the case where the lens group is divided by the change of the interval only at the time of zooming is referred to as “classification 1”, and the case where the lens group is divided by the change of the interval at the time of zooming, focusing, and correction of camera shake is “divided”. 2 ".

  Hereinafter, numerical data of each of the above embodiments will be shown. In the surface data, r is the radius of curvature of each lens surface, d is the distance between each lens surface, nd is the refractive index of the d line of each lens, vd is the Abbe number of each lens, and * is an aspheric surface.

  In the zoom data, f is the focal length of the variable power optical system, and FNO. Is the F number, ω is the half angle of view, IH is the image height, LTL is the total length of the optical system, and BF is the back focus. The back focus is the distance from the optical surface closest to the image side to the paraxial image surface. The total length is obtained by adding the back focus to the distance from the lens surface closest to the object to the lens surface closest to the image. WE is the wide-angle end, ST is the intermediate focal length state, and TE is the telephoto end.

The aspherical shape is represented by the following equation, where z is the optical axis direction, y is the direction orthogonal to the optical axis, k is the cone coefficient, and A4, A6, A8, A10, A12. expressed.
^{z = (y 2 / r)} / [1+ {1- (1 + k) (y / r) 2} 1/2]
^{+ A4y 4 + A6y 6 + A8y} 8 + A10y 10 + A12y 12 + ...
In the aspheric coefficient, “en” (n is an integer) indicates “10− ⁿ ”. Note that the symbols of these specification values are common to numerical data in the embodiments described later.

Numerical example 1
Unit: mm

Surface data surface number rd nd νd
Physical surface ∞ ∞
1 76.358 1.400 1.85478 24.80
2 34.099 9.961 1.49700 81.54
3 750.873 0.150
4 35.998 6.007 1.83481 42.73
5 128.422 variable
6 115.893 0.800 1.77250 49.60
7 9.600 6.946
8 * -19.203 0.820 1.85135 40.10
9 * 18.055 0.828
10 28.409 3.119 2.00069 25.46
11 -42.211 Variable
12 (aperture) ∞ variable
13 * 21.462 4.500 1.80610 40.88
14 * -69.689 0.100
15 16.891 2.110 2.00069 25.46
16 9.055 4.952 1.49700 81.54
17 -35.239 Variable
18 * -29.799 0.858 1.51633 64.14
19 * 11.466 Variable
20 * 19.994 4.974 1.59201 67.02
21 * -11.555 variable
22 -67.886 0.523 1.92286 20.88
23 9.332 3.735 1.90043 37.37
24 -50.184 4.825
Image plane ∞

Aspheric surface data 8th surface
k = 0.0000
A4 = 1.4190e-004, A6 = -5.0390e-006, A8 = 1.1656e-007,
A10-1.4459e-009, A12 = 6.9370e-012, A14 = 0.0000e + 000
9th page
k = 0.0000
A4 = 3.1502e-005, A6 = -4.6522e-006, A8 = 1.1052e-007,
A10 = -1.3514e-009, A12 = 6.5108e-012, A14 = 0.0000e + 000
Thirteenth
k = 0.0000
A4 = -1.1778e-005, A6 = -1.4823e-007, A8 = 3.9038e-009,
A10 = -1.2515e-010, A12 = 5.4754e-013, A14 = 0.0000e + 000
Side 14
k = 0.0000
A4 = 1.6142e-005, A6 = -9.8514e-008, A8 = -4.7755e-009,
A10 = 2.6274e-011, A12 = -2.5866e-013, A14 = 0.0000e + 000
18th page
k = 0.0000
A4 = -4.4383e-004, A6 = 4.0371e-006, A8 = 1.3468e-007,
A10 = -4.6965e-009, A12 = 6.9962e-011, A14 = 0.0000e + 000
19th page
k = 0.0000
A4 = -5.4052e-004, A6 = -1.3916e-006, A8 = 3.0352e-007,
A10 = -8.0286e-009, A12 = 1.0508e-010, A14 = 0.0000e + 000
20th page
k = 0.0000
A4 = -3.4323e-005, A6 = -3.0201e-006, A8 = 2.2878e-008,
A10 = -9.9332e-010, A12 = 0.0000e + 000, A14 = 0.0000e + 000
Surface 21
k = 0.0000
A4 = 2.7302e-004, A6 = -3.3353e-006, A8 = 7.7118e-009,
A10 = -3.8748e-010, A12 = 0.0000e + 000, A14 = 0.0000e + 000

Zoom data
WE ST TE
f 4.001 14.360 58.297
FNO. 1.417 2.395 3.630
2ω 86.3 27.6 6.8
IH 3.60 3.60 3.60
LTL 112.102 112.102 112.102
BF 4.825 4.825 4.825

d5 0.401 21.095 32.932
d11 33.728 13.034 1.197
d12 10.618 7.177 1.195
d17 0.999 5.013 11.520
d19 7.557 7.640 7.635
d21 2.190 1.534 1.014

Each group focal length
f1 = 58.51995 f2 = -9.45149 f3 = 15.19986 f4 = -15.9238
f5 = 13.14017 f6 = 389.62769

Numerical example 2
Unit: mm

Surface data surface number rd nd νd
Physical surface ∞ ∞
1 81.040 1.400 1.85478 24.80
2 31.264 8.940 1.49700 81.54
3 354.912 0.150
4 36.279 5.450 1.90043 37.37
5 172.059 Variable
6 107.527 0.800 1.75500 52.32
7 10.000 6.239
8 * -20.630 0.800 1.85135 40.10
9 * 22.049 2.062
10 41.189 2.700 2.00069 25.46
11 -53.219 Variable
12 (aperture) ∞ variable
13 * 17.884 3.700 1.82080 42.71
14 * -98.517 0.739
15 24.943 0.550 1.95375 32.32
16 9.050 5.700 1.59282 68.63
17 -30.778 variable
18 * -15.087 0.550 1.49700 81.54
19 * 13.007 6.050
20 * 14.756 5.219 1.49700 81.54
21 * -12.076 0.800
22 31.498 0.500 1.92286 18.90
23 8.411 4.250 1.88300 40.76
24 87.922 5.200
Image plane ∞

Aspheric surface data 8th surface
k = 0.0000
A4 = 2.1520e-004, A6 = -6.4489e-006, A8 = 9.7910e-008,
A10 = -7.9110e-010, A12 = 2.5549e-012, A14 = 0.0000e + 000
9th page
k = 0.0000
A4 = 1.3630e-004, A6 = -6.1502e-006, A8 = 9.1768e-008,
A10 = -6.2920e-010, A12 = 1.4410e-012, A14 = 0.0000e + 000
Thirteenth
k = 0.0000
A4 = -1.3970e-005, A6 = 4.7758e-007, A8 = -1.3134e-008,
A10 = 8.1039e-011, A12 = 0.0000e + 000, A14 = 0.0000e + 000
Side 14
k = 0.0000
A4 = 2.9296e-005, A6 = 1.9795e-007, A8 = -9.9355e-009,
A10 = 6.0400e-011, A12 = 0.0000e + 000, A14 = 0.0000e + 000
18th page
k = 0.0000
A4 = -3.4204e-004, A6 = 9.6433e-006, A8 = 4.7726e-009,
A10 = -1.8121e-009, A12 = 0.0000e + 000, A14 = 0.0000e + 000
19th page
k = 0.0000
A4 = -5.1284e-004, A6 = 5.8114e-006, A8 = 7.5767e-008,
A10 = -2.2253e-009, A12 = 0.0000e + 000, A14 = 0.0000e + 000
20th page
k = 0.0000
A4 = -1.1498e-006, A6 = -2.2945e-006, A8 = 4.0844e-009,
A10 = -5.8297e-011, A12 = 0.0000e + 000, A14 = 0.0000e + 000
Surface 21
k = 0.0000
A4 = 3.1930e-004, A6 = -2.8428e-006, A8 = 4.3333e-009,
A10 = 7.6108e-012, A12 = 0.0000e + 000, A14 = 0.0000e + 000

Zoom data
WE ST TE
f 3.951 14.220 44.208
FNO. 1.634 1.902 1.972
2ω 86.4 26.5 8.6
IH 3.41 3.41 3.41
LTL 106.27 106.27 106.27
BF 5.200 5.200 5.200

d5 0.373 21.442 32.369
d11 33.356 12.287 1.360
d12 8.080 4.581 1.072
d17 2.662 6.161 9.670
Each group focal length
f1 = 56.59748 f2 = -9.95663 f3 = 15.24881 f4 = -13.96397
f5 = 14.28508 f6 = 65.84716

Numerical example 3
Unit: mm

Surface data surface number rd nd νd
Physical surface ∞ ∞
1 96.913 1.600 1.92119 23.96
2 35.025 6.931 1.51633 64.14
3 275.273 0.250
4 42.405 4.600 1.91082 35.25
5 264.575 Variable
6 264.575 0.950 1.78800 47.37
7 10.900 5.812
8 * -120.313 0.800 1.85135 40.10
9 * 15.518 5.151
10 45.483 2.700 1.92286 20.88
11 -120.498 variable
12 (aperture) ∞ variable
13 * 19.628 4.725 1.80610 40.88
14 * -850.000 5.541
15 28.431 0.650 1.85478 24.80
16 10.174 5.150 1.49700 81.54
17 -30.905 Variable
18 * -58.733 0.700 1.58313 59.38
19 * 11.744 variable
20 * 13.004 3.800 1.58313 59.38
21 * -850.000 3.800
22 18.320 0.600 2.00100 29.13
23 8.400 5.727 1.61800 63.40
24 -31.484 2.042
25 ∞ 0.500 1.51633 64.14
26 ∞ 3.500
Image plane ∞

Aspheric surface data 8th surface
k = 0.0000
A4 = 1.5897e-004, A6 = -4.6243e-006, A8 = 6.0294e-008,
A10 = -4.3744e-010, A12 = 1.4215e-012, A14 = 0.0000e + 000
9th page
k = 0.0000
A4 = 5.4622e-005, A6 = -4.8681e-006, A8 = 6.2006e-008,
A10 = -4.3749e-010, A12 = 1.3677e-012, A14 = 0.0000e + 000
Thirteenth
k = 0.0000
A4 = -8.0152e-007, A6 = -3.4395e-007, A8 = 9.0517e-009,
A10 = -1.4953e-010, A12 = 9.3464e-013, A14 = 0.0000e + 000
Side 14
k = 0.0000
A4 = 2.4705e-005, A6 = -4.0759e-007, A8 = 1.0962e-008,
A10 = -2.0152e-010, A12 = 1.4434e-012, A14 = 0.0000e + 000
18th page
k = 0.0000
A4 = 1.5541e-004, A6 = -6.7393e-006, A8 = 2.3846e-007,
A10 = -5.0744e-009, A12 = 5.5675e-011, A14 = 0.0000e + 000
19th page
k = 0.0000
A4 = 1.4156e-004, A6 = -9.5105e-006, A8 = 3.6964e-007,
A10 = -8.9290e-009, A12 = 1.0492e-010, A14 = 0.0000e + 000
20th page
k = 0.0000
A4 = 2.1326e-005, A6 = -1.5883e-006, A8 = 2.2701e-008,
A10 = -3.9311e-010, A12 = 1.3883e-012, A14 = 0.0000e + 000
Surface 21
k = 0.0000
A4 = 8.9785e-005, A6 = -2.2240e-006, A8 = 4.2912e-008,
A10 = -8.1741e-010, A12 = 4.8550e-012, A14 = 0.0000e + 000

Zoom data
WE ST TE
f 3.920 13.900 55.458
FNO. 1.642 2.762 3.803
2ω 93.9 31.9 8.1
IH 4.00 4.00 4.00
LTL 135.2677 135.2677 135.2677
BF 3.500 3.500 3.500

d5 0.701 19.946 37.993
d11 38.792 19.547 1.500
d12 25.310 5.263 1.200
d17 1.806 8.048 22.221
d19 3.300 17.105 6.995

Each group focal length
f1 = 69.5426 f2 = -10.66131 f3 = 21.0955 f4 = -16.72209
f5 = 22.00062 f6 = 35.18717

Numerical example 4
Unit: mm

Surface data surface number rd nd νd
Physical surface ∞ ∞
1 96.913 1.600 1.92119 23.96
2 35.025 6.931 1.51633 64.14
3 275.273 0.250
4 42.405 4.600 1.91082 35.25
5 264.575 Variable
6 264.575 0.950 1.78800 47.37
7 10.900 5.812
8 * -120.313 0.800 1.85135 40.10
9 * 15.518 5.151
10 45.483 2.700 1.92286 20.88
11 -120.498 variable
12 (aperture) ∞ variable
13 * 19.628 4.725 1.80610 40.88
14 * -850.000 5.541
15 28.431 0.650 1.85478 24.80
16 10.174 5.150 1.49700 81.54
17 -30.905 Variable
18 * -58.733 0.700 1.58313 59.38
19 * 11.744 3.300
20 * 13.004 3.800 1.58313 59.38
21 * -850.000 3.800
22 18.320 0.600 2.00100 29.13
23 8.400 5.727 1.61800 63.40
24 -31.484 5.870
Image plane ∞

Aspheric surface data 8th surface
k = 0.0000
A4 = 1.5897e-004, A6 = -4.6243e-006, A8 = 6.0294e-008,
A10 = -4.3744e-010, A12 = 1.4215e-012, A14 = 0.0000e + 000
9th page
k = 0.0000
A4 = 5.4622e-005, A6 = -4.8681e-006, A8 = 6.2006e-008,
A10 = -4.3749e-010, A12 = 1.3677e-012, A14 = 0.0000e + 000
Thirteenth
k = 0.0000
A4 = -8.0152e-007, A6 = -3.4395e-007, A8 = 9.0517e-009,
A10 = -1.4953e-010, A12 = 9.3464e-013, A14 = 0.0000e + 000
Side 14
k = 0.0000
A4 = 2.4705e-005, A6 = -4.0759e-007, A8 = 1.0962e-008,
A10 = -2.0152e-010, A12 = 1.4434e-012, A14 = 0.0000e + 000
18th page
k = 0.0000
A4 = 1.5541e-004, A6 = -6.7393e-006, A8 = 2.3846e-007,
A10 = -5.0744e-009, A12 = 5.5675e-011, A14 = 0.0000e + 000
19th page
k = 0.0000
A4 = .4156e-004, A6 = -9.5105e-006, A8 = 3.6964e-007,
A10 = -8.9290e-009, A12 = 1.0492e-010, A14 = 0.0000e + 000
20th page
k = 0.0000
A4 = 2.1326e-005, A6 = -1.5883e-006, A8 = 2.2701e-008,
A10 = -3.9311e-010, A12 = 1.3883e-012, A14 = 0.0000e + 000
Surface 21
k = 0.0000
A4 = 8.9785e-005, A6 = -2.2240e-006, A8 = 4.2912e-008,
A10 = -8.1741e-010, A12 = 4.8550e-012, A14 = 0.0000e + 000

Zoom data
WE ST TE
f 3.920 12.513 53.868
FNO. 1.702 2.246 3.635
2ω 88.0 30.9 7.4
IH 3.57 3.57 3.57
LTL 135.268 121.687 131.637
BF 5.870 5.870 5.870

d5 0.702 19.945 37.993
d11 42.422 9.598 1.500
d12 21.680 15.215 1.200
d17 1.807 8.272 22.287

Each group focal length
f1 = 69.5426 f2 = -10.66131 f3 = 21.0955 f4 = -16.72209
f5 = 22.00062 f6 = 35.18716

Numerical example 5
Unit: mm

Surface data surface number rd nd νd
Physical surface ∞ ∞
1 96.913 1.600 1.92119 23.96
2 35.025 6.931 1.51633 64.14
3 275.273 0.250
4 42.405 4.600 1.91082 35.25
5 264.575 Variable
6 264.575 0.950 1.78800 47.37
7 10.900 5.812
8 * -120.313 0.800 1.85135 40.10
9 * 15.518 5.151
10 45.483 2.700 1.92286 20.88
11 -120.498 variable
12 (aperture) ∞ variable
13 * 19.628 4.725 1.80610 40.88
14 * -850.000 5.541
15 28.431 0.650 1.85478 24.80
16 10.174 5.150 1.49700 81.54
17 -30.905 Variable
18 * -58.733 0.700 1.58313 59.38
19 * 11.744 variable
20 * 13.004 3.800 1.58313 59.38
21 -25.125 0.500 1.60562 43.70
22 -850.000 3.500
23 18.320 0.600 2.00100 29.13
24 8.400 5.727 1.63854 55.38
25 -31.484 1.986
26 ∞ 0.500 1.51633 64.14
27 ∞ 3.500
Image plane ∞

Aspheric surface data 8th surface
k = 0.0000
A4 = 1.5897e-004, A6 = -4.6243e-006, A8 = 6.0294e-008,
A10 = -4.3744e-010, A12 = 1.4215e-012, A14 = 0.0000e + 000
9th page
k = 0.0000
A4 = 5.4622e-005, A6 = -4.8681e-006, A8 = 6.2006e-008,
A10 = -4.3749e-010, A12 = 1.3677e-012, A14 = 0.0000e + 000
Thirteenth
k = 0.0000
A4 = -8.0152e-007, A6 = -3.4395e-007, A8 = 9.0517e-009,
A10 = -1.4953e-010, A12 = 9.3464e-013, A14 = 0.0000e + 000
Side 14
k = 0.0000
A4 = 2.4705e-005, A6 = -4.0759e-007, A8 = 1.0962e-008,
A10 = -2.0152e-010, A12 = 1.4434e-012, A14 = 0.0000e + 000
18th page
k = 0.0000
A4 = 1.5541e-004, A6 = -6.7393e-006, A8 = 2.3846e-007,
A10 = -5.0744e-009, A12 = 5.5675e-011, A14 = 0.0000e + 000
19th page
k = 0.0000
A4 = 1.4156e-004, A6 = -9.5105e-006, A8 = 3.6964e-007,
A10 = -8.9290e-009, A12 = 1.0492e-010, A14 = 0.0000e + 000
20th page
k = 0.0000
A4 = -4.0000e-005, A6 = -8.0000e-007, A8 = 2.4500e-008,
A10 = -4.0300e-010, A12 = 1.6334e-012, A14 = 9.5550e-015

Zoom data
WE ST TE
f 3.858 13.681 54.586
FNO. 1.616 2.718 3.743
2ω 93.6 31.6 8.1
IH 3.90 3.90 3.90
LTL 135.4117 135.4117 135.4117
BF 3.500 3.500 3.500

d5 0.701 19.946 37.993
d11 38.792 19.547 1.500
d12 25.310 5.263 1.201
d17 1.806 8.048 22.220
d19 3.300 17.105 6.995

Each group focal length
f1 = 69.5426 f2 = -10.66131 f3 = 21.0955 f4 = -16.72209
f5 = 22.3873 f6 = 31.96736

Numerical example 6
Unit: mm

Surface data surface number rd nd νd
Physical surface ∞ ∞
1 79.517 1.100 2.00330 28.27
2 45.491 6.851 1.43700 95.10
3 -687.604 0.100
4 50.578 4.150 1.49700 81.54
5 555.118 0.100
6 29.923 4.250 1.59282 68.63
7 76.911 Variable
8 * 150.040 0.650 1.88202 37.22
9 * 5.666 4.069
10 -13.844 0.700 1.88300 40.76
11 334.372 0.100
12 21.015 1.900 1.95906 17.47
13 -68.494 Variable
14 (aperture) ∞ 0.800
15 * 16.100 6.517 1.49700 81.54
16 * -18.939 0.144
17 30.290 0.800 1.95906 17.47
18 20.553 5.602 1.59282 68.63
19 -23.052 0.830
20 * -62.097 0.600 1.69680 55.53
21 * 14.000 variable
22 * 11.683 2.600 1.49700 81.54
23 * -38.228 Variable
24 -50.000 0.500 1.65412 39.68
25 5.000 3.917 1.53775 74.70
26 -18.511 2.794
Image plane ∞

Aspheric surface data 8th surface
k = 0.0000
A4 = 1.4563e-004, A6 = -8.1300e-006, A8 = 2.4155e-007,
A10 = -4.3334e-009, A12 = 3.2588e-011, A14 = 0.0000e + 000
9th page
k = 0.0000
A4 = 4.2136e-005, A6 = -2.1915e-005, A8 = 9.8346e-007,
A10 = -3.7075e-008, A12 = -8.9279e-011, A14 = 0.0000e + 000
15th
k = 0.0000
A4 = -6.8790e-005, A6 = -9.3832e-008, A8 = 3.1300e-010,
A10 = -1.0048e-012
16th page
k = 0.0000
A4 = 1.1899e-004, A6 = -4.1425e-007, A8 = 3.6636e-009,
A10 = -5.2358e-012, A12 = 0.0000e + 000, A14 = 0.0000e + 000
20th page
k = 0.0000
A4 = 1.4274e-004, A6 = -3.1072e-006, A8 = 7.8038e-008,
A10 = -8.8650e-010, A12 = 7.2486e-012, A14 = -5.0943e-014
Surface 21
k = 0.0000
A4 = 6.8931e-005, A6 = -1.5697e-006, A8 = 1.3021e-008,
A10 = 8.2153e-010, A12 = 8.8275e-012, A14 = -3.6668e-013
Surface 22
k = 0.0000
A4 = -5.9011e-005, A6 = -1.2149e-007, A8 = -1.4798e-007,
A10 = 0.0000e + 000, A12 = 0.0000e + 000, A14 = 0.0000e + 000
Surface 23
k = 0.0000
A4 = 7.2308e-005, A6 = 1.6790e-006, A8 = -3.2715e-007,
A10 = 4.4426e-009, A12 = 0.0000e + 000, A14 = 0.0000e + 000

Zoom data
WE ST TE
f 4.351 24.502 109.997
FNO. 1.258 2.799 4.475
2ω 76.6 15.0 3.3
IH 3.30 3.30 3.30
LTL 94.333 94.333 94.333
BF 2.794 2.794 2.794

d7 0.412 23.766 32.083
d13 33.048 9.694 1.377
d21 9.731 2.989 10.014
d23 2.068 8.810 1.785

Each group focal length
f1 = 45.45958 f2 = -6.61814 f3 = 12.30182 f4 = -16.3426
f5 = 18.32165 f6 = -218.10859

Next, the values of the conditional expressions in each embodiment are listed below. The value described in the following (1) corresponds to the value of the conditional expression (1-1).

Example 1 Example 2 Example 3
(1) DG5G6aw / fG5 0.167 0.056 0.173
(2) ΔSS / LTLw 0 0 0
(3) | fG2 / fw | 2.362 2.520 2.720
(4) fG2 × PG1G2a 0.008 0.035 0.000
(5) (LTLt-LTLw) / LTLw 0.000 0.000 0.000
(6) fG1 / fw 14.626 14.325 17.741
(7) fG1 / ft 1.004 1.280 1.254
(8) | fG1 / fG2 | 6.192 5.684 6.523
(9) fG3 / fw 3.799 3.860 5.382
(10) DTw -4.03 -8.01 -4.75
(11) νdG3P1 81.54 68.63 81.54
(12) νdG4N1 64.14 81.54 59.38
(13) SFG4 0.444 0.074 0.667
(14) fG5 / fG56w 0.985 1.206 1.387
(15) | fG5 / fG4 | 0.825 1.023 1.316
(16) DG56aw / fG56w 0.164 0.068 0.240
(17) DG56aw / fw 0.547 0.202 0.969
(18) | MGG4backw × (MGG4w-1) | 0.795 0.809 0.878
(19) νdG5P 67.02 81.54 59.38
(20) νdG6N 20.88 18.9 29.13
(21) fG1 / fG3 3.85 3.712 3.297
(22) | fG3 / fG4 | 0.955 1.092 1.262
(23) fG2 / fG4 0.594 0.713 0.638
(24) | fG2 / fG3 | 0.622 0.653 0.505
(25) fG1 × PG1NPa 0.000 0.000 0.000
(26) fG5 / fw 3.284 3.616 5.613
(27) SFG5 0.267 0.100 -0.970
(28) ΩHw / 2 39.260 39.314 43.045
(29) ft / fw 14.571 11.190 14.148
(30) FNOw 1.417 1.634 1.642
(31) FNOt 3.630 1.972 3.803
(32) ft / fw + 143.9
× tan (ΩHw / 2) -121.88 10.3 7.1 26.7
(33) ft / fw + 126.52
× tan (ΩHw / 2) -101.91 16.1 12.9 30.4
(34) ft / fw + 13.38
× tan (ΩHw / 2) -21.0 4.5 1.1 5.6
(35) ft / fw + 80.72
× tan (ΩHw / 2) -62.0 18.5 15.3 27.5
(36) ΣG1 / LTLw 0.156 0.150 0.099
(37) | fG5 / fG6 | 0.034 0.217 0.625
(38) Rimg 3.600 3.414 4.000

Example 4 Example 5 Example 6
(1) DG5G6aw / fG5 0.173 0.156 0.113
(2) ΔSS / LTLw 0 0 0
(3) | fG2 / fw ｜ 2.720 2.763 1.521
(4) fG2 × PG1G2a 0.000 0.000 -0.042
(5) (LTLt-LTLw) / LTLw -0.027 0.000 0.000
(6) fG1 / fw 17.741 18.025 10.448
(7) fG1 / ft 1.291 1.274 0.413
(8) | fG1 / fG2 | 6.523 6.523 6.869
(9) fG3 / fw 5.382 5.468 2.827
(10) DTw -5.77 -5.12 -4.04
(11) νdG3P1 81.54 81.54 81.54
(12) νdG4N1 59.38 59.38 55.53
(13) SFG4 0.667 0.667 0.632
(14) fG5 / fG56w 1.387 1.441 0.855
(15) | fG5 / fG4 | 1.316 1.339 1.121
(16) DG56aw / fG56w 0.240 0.225 0.097
(17) DG56aw / fw 0.969 0.907 0.475
(18) | MGG4backw × (MGG4w-1) | 0.878 0.864 0.944
(19) νdG5P 59.38 59.38 81.54
(20) νdG6N 29.13 29.13 39.68
(21) fG1 / fG3 3.297 3.297 3.695
(22) | fG3 / fG4 | 1.262 1.262 0.753
(23) fG2 / fG4 0.638 0.638 0.405
(24) | fG2 / fG3 | 0.505 0.505 0.538
(25) fG1 × PG1NPa 0.000 0.000 0.000
(26) fG5 / fw 5.612 5.803 4.211
(27) SFG5 -0.970 -0.970 -0.532
(28) ΩHw / 2 40.116 42.887 34.570
(29) ft / fw 13.742 14.148 25.281
(30) FNOw 1.702 1.616 1.258
(31) FNOt 3.635 3.743 4.475
(32) ft / fw + 143.9
× tan (ΩHw / 2) -121.88 13.1 25.9 2.6
(33) ft / fw + 126.52
× tan (ΩHw / 2) -101.91 18.4 29.8 10.6
(34) ft / fw + 13.38
× tan (ΩHw / 2) -21.0 4.0 5.6 13.5
(35) ft / fw + 80.72
× tan (ΩHw / 2) -62.0 19.8 27.1 18.9
(36) ΣG1 / LTLw 0.099 0.099 0.176
(37) | fG5 / fG6 | 0.625 0.700 0.084
(38) Rimg 3.570 3.900 3.300

  FIG. 13 is a sectional view of a single-lens mirrorless camera as an electronic imaging device. In FIG. 13, a photographing optical system 2 can be arranged in a lens barrel of the single-lens mirrorless camera 1. The mount 3 makes the photographing optical system 2 detachable from the body of the single lens mirrorless camera 1. As the mount 3, a screw type mount, a bayonet type mount, or the like can be used. In this example, a bayonet type mount is used, but the present invention is not limited to this. Further, an imaging element surface 4 and a back monitor 5 can be arranged on the body of the single-lens mirrorless camera 1. Note that an image sensor, a small-sized CCD or CMOS, or the like may be used as the image sensor.

  As the photographing optical system 2 of the single-lens mirrorless camera 1, for example, the variable power optical systems shown in the above-described first to sixth embodiments can be used.

  14 and 15 are conceptual diagrams of the configuration of the imaging device. FIG. 14 is a front perspective view of a digital camera 40 as an imaging device, and FIG. 15 is a rear perspective view of the same. The zoom optical system of the present embodiment can be used as the photographing optical system 41 of the digital camera 40.

  The digital camera 40 of this embodiment can include a photographing optical system 41 located on a photographing optical path 42, a shutter button 45, a liquid crystal display monitor 47, and the like. When the shutter button 45 disposed on the upper part of the digital camera 40 is pressed, the photographing can be performed through the photographing optical system 41, for example, the variable magnification optical system of the first embodiment in conjunction with the pressing. An object image formed by the photographing optical system 41 can be formed on an image sensor (photoelectric conversion surface) provided near the imaging plane. The object image received by the image sensor can be displayed as an electronic image on a liquid crystal display monitor 47 provided on the back of the camera by the processor. The photographed electronic image can be recorded in a memory.

  FIG. 16 is a block diagram showing an internal circuit of a main part of the digital camera 40. In the following description, the above-described processor may be configured by, for example, the CDS / ADC 24, the temporary storage memory 17, the processor 18, and the like. The memory can be constituted by the storage 19 and the like.

  As shown in FIG. 16, the digital camera 40 is connected to the input device 12, a control unit 13 connected to the input device 12, and a control signal output port of the control unit 13 via buses 14 and 15. It may include an imaging drive circuit 16 and a temporary storage memory 17, a processor 18, a storage 19, a display 20, and a setting information storage memory 21.

  The above-described temporary storage memory 17, processor 18, storage 19, display 20, and setting information storage memory 21 can mutually input and output data via a bus 22. Further, the image sensor 49 and the CDS / ADC 24 can be connected to the image drive circuit 16.

  The input device 12 may include various input buttons and switches. Event information input from outside (camera user) can be notified to the control unit 13 via these. The control unit 13 is a central processing unit including, for example, a CPU, and has a built-in program memory (not shown), and can control the entire digital camera 40 according to a program stored in the program memory.

  The imaging sensor 49 is driven and controlled by the imaging drive circuit 16, converts the amount of light of each pixel of the object image formed via the imaging optical system 41 into an electric signal, and outputs the electric signal to the CDS / ADC 24.

  The CDS / ADC 24 amplifies an electric signal input from the image sensor 49, performs analog / digital conversion, and performs raw image data (Bayer data, hereinafter referred to as RAW data) only after the amplification and digital conversion. Can be output to the temporary storage memory 17.

  The temporary storage memory 17 may be a buffer such as an SDRAM, for example, and may be a memory device that temporarily stores RAW data output from the CDS / ADC 24. The processor 18 reads out the RAW data stored in the temporary storage memory 17 or the RAW data stored in the storage 19 and performs various image processing including distortion correction based on the image quality parameter specified by the control unit 13. This is a circuit that can be performed electrically.

  In the storage 19, a card-type or stick-type recording medium such as a flash memory is detachably mounted, and RAW data transferred from the temporary storage memory 17 and image processing by the processor 18 are performed on these flash memories. Image data can be recorded and retained.

  The display 20 is configured by a liquid crystal display monitor 47 or the like, and can display photographed RAW data, image data, an operation menu, and the like. The setting information storage memory 21 may include a ROM unit in which various image quality parameters are stored in advance, and a RAM unit that stores image quality parameters read from the ROM unit by an input operation of the input device 12.

  FIG. 17 shows a configuration of the video conference system. The video conference system 100 may include a plurality of video conference devices 110, 120, and 130. Then, each of the video conference devices 110, 120, and 130 may be connected to a network, for example, a wide area network (WAN) 140.

  The video conference device 110 may include a main body 111, a camera 112, and a display 113. Similarly, the video conference device 120 and the video conference device 130 may include similar units. The camera 112 may include, for example, the variable power optical system according to the first embodiment and an image sensor. Through the camera 112, conference participants and conference materials can be photographed.

  The video conference devices 110, 120, and 130 can be arranged at bases (remote locations) apart from each other. Thus, the video of each of the conference participants 119, 129, 139 can be transmitted via the wide area network (WAN) 140 to a video conference device used by other conference participants. As a result, an image 129 'of the conference participant 129 and an image 139' of the conference participant 139 can be displayed on the display 113. Also, audio can be transmitted along with the transmission of the video. The same applies to the displays 123 and 133.

  In this way, by using the video conference system 100, each of the conference participants 119, 129, and 139 confirms the state and speech contents of the conference participants other than itself even if the bases are remote. While the meeting can proceed. Note that the video conference devices used at each site do not necessarily need to be the same device.

  The present invention can take various modifications without departing from the spirit thereof. Also, the number of shapes shown in each of the above embodiments is not necessarily limited. In each of the above embodiments, the cover glass does not necessarily have to be provided. Further, a lens which is not shown in the above embodiments and which has substantially no refractive power may be arranged in each lens group or outside each lens group.

  As described above, the present invention can secure a wide angle of view and a small F-number at the wide-angle end, and is suitable for a variable power optical system in which various aberrations are satisfactorily corrected and an imaging apparatus including the same. ing.

G1 First lens group G2 Second lens group G3 Third lens group G4 Fourth lens group G5 Fifth lens group G6 Sixth lens group S Aperture stop C Cover glass I Image plane 1 Single lens mirrorless camera 2 Photographing optical system 3 Mirror Mount of cylinder 4 Image sensor surface 5 Back monitor 12 Input device 13 Control unit 14, 15 Bus 16 Imaging drive circuit 17 Temporary storage memory 18 Processor 19 Storage 20 Display 21 Setting information storage memory 22 Bus 24 CDS / ADC
Reference Signs List 40 digital camera 41 shooting optical system 42 shooting optical path 45 shutter button 47 liquid crystal display monitor 49 image sensor 100 video conference system 110, 120, 130 video conference device 111, 121, 131 main body 112, 122, 132 camera 113, 123, 133 Display 119, 129, 139 Conference participants 119 ', 129', 139 'Video of conference participants 140 Wide area network (WAN)

Claims (59)

From the object side,
A first lens group having a positive refractive power;
A second lens group having a negative refractive power;
A third lens group having a positive refractive power;
A fourth lens group having a negative refractive power;
A fifth lens group having a positive refractive power;
And a sixth lens group consists of,
The sixth lens group includes a negative lens and a positive lens,
At the time of at least one of zooming, focusing, or camera shake correction, each lens group moves relatively differently with respect to the adjacent lens group,
The second lens group moves so that an interval between the first lens group and the second lens group increases from a wide-angle end to a telephoto end,
The diaphragm apertures, a lens surface positioned nearest to the image side in the second lens group, a lens surface positioned nearest to the image side in the third lens group, or located between, or, the third lens Adjacent to the lens surface located closest to the image side in the group,
During zooming, the fourth lens group is fixed,
The fourth lens group moves in a direction orthogonal to the optical axis,
At the time of zooming, the sixth lens group is fixed,
The first lens group includes a negative lens and two positive meniscus lenses both having a convex surface facing the object side,
The first lens group has no reflecting surface,
The fifth lens group includes a single lens or a cemented lens,
A variable power optical system characterized by satisfying the following conditional expression (1).
0.012 ≦ DG5G6aw / fG5 ≦ 5.0 (1)
here,
DG5G6aw is an air gap between the fifth lens unit and the sixth lens unit at a wide-angle end,
fG5 is the focal length of the fifth lens group,
It is. The variable power optical system according to claim 1, wherein the fifth lens group moves in at least one of a direction along an optical axis and a direction orthogonal to the optical axis. The variable power optical system according to claim 2, wherein the fifth lens group moves in a direction along an optical axis during zooming. 3. The fifth lens group moves in a direction along an optical axis during focusing.
Or the variable power optical system according to 3. The variable power optical system according to claim 4, wherein at the time of zooming, the distance between the fifth lens group and the sixth lens group is constant. The variable power optical system according to any one of claims 1 to 5, wherein a total length of the variable power optical system is constant at the time of variable power. The variable power optical system according to any one of claims 1 to 6, wherein the following conditional expression (2) is satisfied.
0.0 ≦ ΔSS / LTLw ≦ 0.11 (2)
here,
ΔSS is the maximum value of the amount of movement of the aperture stop during zooming,
LTLw is the total length of the variable power optical system at the wide-angle end,
It is. The variable power optical system according to any one of claims 1 to 7, wherein the following conditional expression (3) is satisfied.
1.30 ≦ | fG2 / fw | ≦ 4.50 (3)
here,
fG2 is the focal length of the second lens group,
fw is the focal length of the variable power optical system at the wide angle end,
It is. The variable power optical system according to any one of claims 1 to 8, wherein the following conditional expression (4) is satisfied.
−0.065 ≦ fG2 × PG1G2a ≦ 0.190 (4)
here,
PG1G2a is represented by the following equation:
PG1G2a = 1 / RG1B-1 / RG2F,
RG1B is the radius of curvature of the lens surface of the first lens group located closest to the image,
RG2F is a radius of curvature of a lens surface of the second lens group located closest to the object,
It is. The variable power optical system according to any one of claims 1 to 9, wherein the following conditional expression (5) is satisfied.
−0.11 ≦ (LTLt−LTLw) /LTLw≦0.11 (5)
here,
LTLt is the total length of the variable power optical system at the telephoto end,
LTLw is the total length of the variable power optical system at the wide-angle end,
It is. The variable power optical system according to claim 1, wherein the following conditional expression (6) is satisfied.
4.0 ≦ fG1 / fw ≦ 35 (6)
here,
fG1 is the focal length of the first lens group,
fw is the focal length of the variable power optical system at the wide angle end,
It is. The variable power optical system according to claim 1, wherein the following conditional expression (7) is satisfied.
0.30 ≦ fG1 / ft ≦ 2.5 (7)
here,
fG1 is the focal length of the first lens group,
ft is the focal length of the variable power optical system at the telephoto end,
It is. 13. The variable power optical system according to claim 1, wherein the following conditional expression (8) is satisfied.
3.5 ≦ | fG1 / fG2 | ≦ 9.1 (8)
here,
fG1 is the focal length of the first lens group,
fG2 is the focal length of the second lens group,
It is. 14. The variable power optical system according to claim 1, wherein the following conditional expression (9) is satisfied.
1.0 ≦ fG3 / fw ≦ 8.0 (9)
here,
fG3 is the focal length of the third lens group,
fw is the focal length of the variable power optical system at the wide angle end,
It is. The variable power optical system according to any one of claims 1 to 14, wherein the following conditional expression (10) is satisfied.
-14% <DTw <5% (10)
here,
DTw is the amount of distortion at the maximum angle of view at the wide-angle end, and is represented by the following equation:
DTw = (IHw1−IHw2) / IHw2 × 100 (%),
IHw1 is an actual image height when a light beam including a light ray having a maximum angle of view at the wide-angle end is formed on an image plane;
IHw2 is a paraxial image height when a light beam including a light ray having a maximum angle of view at the wide-angle end is formed on an image plane,
In each case, the image height at infinity object point focusing,
It is. 16. The variable power optical system according to claim 15, further comprising one positive lens in addition to the two positive meniscus lenses. 17. The variable power optical system according to claim 1, wherein the third lens group includes a positive lens and a negative lens. 18. The variable power optical system according to claim 1, wherein the third lens group moves so as to be located closer to the object side at a telephoto end than at a wide angle end. 18. The variable power optical system according to claim 1, wherein at the time of zooming, the third lens group is fixed. 20. The variable power optical system according to claim 1, wherein the third lens group includes a predetermined positive lens satisfying the following conditional expression (11).
63 ≦ νdG3P1 ≦ 100 (11)
here,
νdG3P1 is the Abbe number of the predetermined positive lens,
It is. The third lens group includes a first positive lens and a cemented lens,
21. The variable power optical system according to claim 1, wherein the cemented lens includes a positive lens and a negative lens. 22. The variable power optical system according to claim 21, wherein the shape of the cemented lens is a meniscus shape having a convex surface facing the object side. The relative position between the third lens group and the fourth lens group or the relative position between the fourth lens group and the fifth lens group changes between a wide-angle end and a telephoto end. The variable power optical system according to any one of claims 1 to 22. 24. The variable power optical system according to claim 1, wherein the fourth lens group includes a predetermined negative lens satisfying the following conditional expression (12).
51 ≦ νdG4N1 ≦ 100 (12)
here,
νdG4N1 is the Abbe number of the predetermined negative lens,
It is. 25. The variable power optical system according to claim 1, wherein the following conditional expression (13) is satisfied.
−1.5 ≦ SFG4 ≦ 1.8 (13)
here,
SFG4 is represented by the following equation:
SFG4 = (RG4f + RG4r) / (RG4f-RG4r),
RG4f is the radius of curvature of the lens surface of the fourth lens group located closest to the object,
RG4r is the radius of curvature of the lens surface of the fourth lens group located closest to the image,
It is. 26. The variable power optical system according to claim 1, wherein the fourth lens group includes one negative lens. 27. The variable power optical system according to claim 1, wherein the sixth lens group includes a negative lens and a positive lens. The fifth lens group includes one positive lens,
The variable-power optical system according to any one of claims 1 to 27, wherein the sixth lens group includes one negative lens and one positive lens. 29. The variable power optical system according to claim 1, wherein the following conditional expression (14) is satisfied.
0.5 ≦ fG5 / fG56w ≦ 2.5 (14)
here,
fG5 is the focal length of the fifth lens group,
fG56w is a composite focal length of the fifth lens unit and the sixth lens unit at the wide-angle end,
It is. 30. The variable power optical system according to claim 1, wherein the following conditional expression (15) is satisfied.
0.5 ≦ | fG5 / fG4 | ≦ 2.5 (15)
here,
fG4 is the focal length of the fourth lens group,
fG5 is the focal length of the fifth lens group,
It is. 31. The variable power optical system according to claim 1, wherein the following conditional expression (16) is satisfied.
0.026 ≦ DG56aw / fG56w ≦ 0.4 (16)
here,
DG56aw is an air gap between the fifth lens unit and the sixth lens unit at the wide-angle end,
fG56w is a composite focal length of the fifth lens unit and the sixth lens unit at the wide-angle end,
It is. 32. The variable power optical system according to claim 1, wherein the following conditional expression (17) is satisfied.
0.1 ≦ DG56aw / fw ≦ 2.0 (17)
here,
DG56aw is an air gap between the fifth lens unit and the sixth lens unit at the wide-angle end,
fw is the focal length of the variable power optical system at the wide angle end,
It is. 33. The variable power optical system according to claim 1, wherein the following conditional expression (18) is satisfied.
0.3 ≦ | MGG4backw × (MGG4w−1) | ≦ 1.5 (18)
here,
MGG4w is a lateral magnification of the fourth lens group at the wide-angle end,
MGG4backw is a lateral magnification in a predetermined optical system at the wide-angle end,
The predetermined optical system is an optical system including all lenses located on the image side of the fourth lens group;
The lateral magnification is the lateral magnification when focusing on an object at infinity,
It is. The fifth lens group includes one positive lens,
The variable power optical system according to any one of claims 1 to 33, wherein the following conditional expression (19) is satisfied.
52 ≦ νdG5P ≦ 100 (19)
here,
νdG5P is the Abbe number of the positive lens in the fifth lens group,
It is. 35. The variable power optical system according to claim 1, wherein the following conditional expression (20) is satisfied.
18.5 ≦ νdG6N ≦ 50 (20)
here,
νdG6N is the minimum Abbe number among the Abbe numbers of the negative lenses in the sixth lens group,
It is. 36. The variable power optical system according to claim 1, wherein the aperture stop is located between the second lens group and the third lens group. 37. The variable power optical system according to claim 1, wherein the aperture stop is fixed at the time of zooming. The variable power optical system according to any one of claims 1 to 37, wherein the following conditional expression (21) is satisfied.
2.3 ≦ fG1 / fG3 ≦ 7 (21)
here,
fG1 is the focal length of the first lens group,
fG3 is the focal length of the third lens group,
It is. The variable power optical system according to any one of claims 1 to 38, wherein the following conditional expression (22) is satisfied.
0.5 ≦ | fG3 / fG4 | ≦ 2.0 (22)
here,
fG3 is the focal length of the third lens group,
fG4 is the focal length of the fourth lens group,
It is. The variable power optical system according to any one of claims 1 to 39, wherein the following conditional expression (23) is satisfied.
0.25 ≦ fG2 / fG4 ≦ 1.5 (23)
here,
fG2 is the focal length of the second lens group,
fG4 is the focal length of the fourth lens group,
It is. 41. The variable power optical system according to claim 1, wherein the following conditional expression (24) is satisfied.
0.25 ≦ | fG2 / fG3 | ≦ 1.5 (24)
here,
fG2 is the focal length of the second lens group,
fG3 is the focal length of the third lens group,
It is. One positive meniscus lens of the first lens group is close to a negative lens of the first lens group;
42. The variable power optical system according to claim 1, wherein the following conditional expression (25) is satisfied.
−0.1 ≦ fG1 × PG1NPa ≦ 0.27 (25)
here,
fG1 is the focal length of the first lens group,
PG1NPa is represented by the following equation:
PG1NPa = 1 / RG1NB-1 / RG1PF,
RG1NB is a radius of curvature of an image-side lens surface of the negative lens of the first lens group,
RG1PF is a radius of curvature of an object-side lens surface of the one positive meniscus lens of the first lens group;
It is. 43. The variable power optical system according to claim 1, wherein the following conditional expression (26) is satisfied.
2.5 ≦ fG5 / fw ≦ 15 (26)
here,
fG5 is the focal length of the fifth lens group,
fw is the focal length of the variable power optical system at the wide angle end,
It is. The variable power optical system according to any one of claims 1 to 43, wherein the following conditional expression (27) is satisfied.
-1.9≤SFG5≤0.95 (27)
here,
SFG5 is represented by the following equation:
SFG5 = (RG5f + RG5r) / (RG5f-RG5r),
RG5f is a radius of curvature of a lens surface of the fifth lens group located closest to the object,
RG5r is the radius of curvature of the lens surface of the fifth lens group located closest to the image,
It is. The variable power optical system according to any one of claims 1 to 44, wherein at the time of zooming, the aperture stop moves in only one direction or is fixed. The variable power optical system according to any one of claims 1 to 45, wherein the following conditional expression (28) is satisfied.
26.9 ° ≦ ΩHw / 2 ≦ 75 ° (28)
here,
ΩHw is the total horizontal angle of view at the wide-angle end,
It is. 47. The variable power optical system according to claim 1, wherein the following conditional expression (29) is satisfied.
5.5 ≦ ft / fw ≦ 120 (29)
here,
ft is the focal length of the variable power optical system at the telephoto end,
fw is the focal length of the variable power optical system at the wide angle end,
It is. The variable power optical system according to any one of claims 1 to 47, wherein the following conditional expression (30) is satisfied.
0.6 ≦ FNOw ≦ 1.84 (30)
here,
FNOw is the F-number at the wide-angle end,
It is. 49. The variable power optical system according to any one of claims 1 to 48, wherein the following conditional expression (31) is satisfied.
0.7 ≦ FNOt ≦ 5.1 (31)
here,
FNOt is the F-number at the telephoto end,
It is. 50. The variable power optical system according to any one of claims 1 to 49, wherein the following conditional expression (32) is satisfied.
−20 ≦ ft / fw + 143.9 × tan (ΩHw / 2) −121.88 ≦ 140 (32)
here,
fw is the focal length of the variable power optical system at the wide angle end,
ft is the focal length of the variable power optical system at the telephoto end,
ΩHw is the total horizontal angle of view at the wide-angle end,
It is. The variable power optical system according to any one of claims 1 to 50, wherein the following conditional expression (33) is satisfied.
−1.5 ≦ ft / fw + 126.52 × tan (ΩHw / 2) −101.91 ≦ 140 (33)
here,
fw is the focal length of the variable power optical system at the wide angle end,
ft is the focal length of the variable power optical system at the telephoto end,
ΩHw is the total horizontal angle of view at the wide-angle end,
It is. 52. The variable power optical system according to claim 1, wherein the following conditional expression (34) is satisfied.
−2.0 ≦ ft / fw + 13.38 × tan (ΩHw / 2) −21.0 ≦ 140 (34)
here,
fw is the focal length of the variable power optical system at the wide angle end,
ft is the focal length of the variable power optical system at the telephoto end,
ΩHw is the total horizontal angle of view at the wide-angle end,
It is. 53. The variable power optical system according to claim 1, wherein the following conditional expression (35) is satisfied.
-3 ≦ ft / fw + 80.72 × tan (ΩHw / 2) −62.0 ≦ 140 (35)
here,
fw is the focal length of the variable power optical system at the wide angle end,
ft is the focal length of the variable power optical system at the telephoto end,
ΩHw is the total horizontal angle of view at the wide-angle end,
It is. The variable power optical system according to any one of claims 1 to 53, further comprising a positive lens and a negative lens between the fifth lens group and an image plane. The variable power optical system according to any one of claims 1 to 54, wherein the following conditional expression (36) is satisfied.
0.04 ≦ ΔG1 / LTLw ≦ 0.33 (36)
here,
ΣG1 is the thickness of the first lens group,
LTLw is the total length of the variable power optical system at the wide-angle end,
It is. The variable power optical system according to any one of claims 1 to 55, wherein at the time of focusing, the fourth lens group and the fifth lens group move together. 57. The variable power optical system according to claim 1, wherein the following conditional expression (37) is satisfied.
0.01 ≦ | fG5 / fG6 | ≦ 3.0 (37)
here,
fG5 is the focal length of the fifth lens group,
fG6 is the focal length of the sixth lens group,
It is. Optics,
An imaging element having an imaging surface and converting an image formed on the imaging surface by the optical system into an electric signal,
58. An imaging apparatus, wherein the optical system is the variable power optical system according to any one of claims 1 to 57. The imaging apparatus according to claim 58, wherein the following conditional expression (38) is satisfied.
2.5mm ≦ Rimg ≦ 40mm (38)
here,
Rimg is the radius of the image circle in the image sensor,
It is.

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