JP2017187639A - Zoom optical system and imaging apparatus including the same - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a zoom optical system ensuring a wide angle of view and a small F number at a wide angle end, in which various aberrations are favorably corrected, and an imaging apparatus including the zoom optical system.SOLUTION: The zoom optical system has a plurality of lens groups; and the plurality of lens groups comprises at least two lens groups having a positive refractive power and one lens group or two or more lens groups having a negative refractive power. The at least two lens groups having a positive refractive power include a positive lens group and an image-side positive lens group. The image-side positive lens group does not move along the optical axis. Each of intervals between adjoining lens groups in the plurality of lens groups vary upon varying a power, focusing, or varying a power and focusing. The positive lens group includes a predetermined positive lens satisfying a conditional formula (2) 60.8≤νdGPMP1≤100.0; and the image-side positive lens group has a first sub lens group and a second sub lens group and satisfies a conditional formula (1) 0.1≤fGBUN1/fGPM≤2.1.SELECTED DRAWING: Figure 1

Description

  The present invention relates to a zoom optical system and an image pickup apparatus including the same.

  In recent years, imaging optical systems have been used in a wide range of fields such as digital cameras, video cameras, surveillance cameras, and video conferencing system cameras.

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

  The zoom optical systems disclosed in Patent Document 2 and Patent Document 3 have, 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-A-2005-49843 JP 2011-221554 A JP 2011-175098 A

  However, in Patent Documents 1 to 3, securing a wide angle of view at the wide-angle end, securing a small F-number, and correcting various aberrations have not been performed simultaneously.

  The present invention has been made in view of such problems, and can provide a zoom optical system capable of ensuring a wide angle of view and a small F-number at the wide-angle end, and in which various aberrations are well corrected. An object of the present invention is to provide an imaging apparatus including the same.

In order to solve the above-described problems and achieve the object, the zoom optical system of the present invention includes:
Having a plurality of lens groups and an aperture stop,
The plurality of lens groups includes two or more lens groups having a positive refractive power and one or more lens groups having a negative refractive power,
The two or more lens groups having positive refractive power include a positive lens group having positive refractive power and an image side positive lens group,
The one or more lens groups having negative refractive power have an object side negative lens group,
The image-side positive lens group does not move along the optical axis both during zooming and in focus,
In the plurality of lens groups, the distance between the adjacent lens groups changes at the time of zooming, focusing, or zooming and focusing,
The positive lens group has the largest refractive power among the two or more lens groups having positive refractive power excluding the image side positive lens group,
The image side positive lens group is located closest to the image side among the two or more lens groups having positive refractive power,
When the plurality of lens groups have two or more lens groups having negative refractive power, the object-side negative lens group is located closest to the object side among one or more lens groups having negative refractive power,
The object-side negative lens group moves so that the distance between the object-side negative lens group and the positive lens group at the time of focusing on an object at infinity is narrower at the telephoto end than at the wide-angle end,
The aperture stop is located between the lens surface located closest to the image side in the object side negative lens group and the lens surface located closest to the image side in the positive lens group, or is located closest to the image side in the positive lens group. Next to the lens surface located at
The image side positive lens group includes a first sub lens group having a positive refractive power and a second sub lens group including a positive lens and a negative lens.

The imaging device of the present invention is
Optical system,
An imaging device having an imaging surface and converting an image formed on the imaging surface by an optical system into an electrical 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 zoom optical system in which a wide angle of view at a wide-angle end and a small F-number can be ensured, and various aberrations are favorably corrected, and an imaging apparatus including the zoom optical system. .

FIG. 3 is a lens cross-sectional view of the zoom optical system of Example 1. 6 is a lens cross-sectional view of a zoom optical system according to Example 2. FIG. 6 is a lens cross-sectional view of a zoom optical system according to Example 3. FIG. 6 is a lens cross-sectional view of a zoom optical system according to Example 4. FIG. 10 is a lens cross-sectional view of a zoom optical system according to Example 5. FIG. 10 is a lens cross-sectional view of a zoom optical system according to Example 6. FIG. 12 is a lens cross-sectional view of a zoom optical system according to Example 7. FIG. 10 is a lens cross-sectional view of a zoom optical system according to Example 8. FIG. FIG. 4 is an aberration diagram of the zoom optical system according to Example 1. 6 is an aberration diagram of the zoom optical system according to Example 2. FIG. FIG. 6 is an aberration diagram of the zoom optical system according to Example 3. FIG. 6 is an aberration diagram of the zoom optical system according to Example 4. FIG. 10 is an aberration diagram of the zoom optical system according to Example 5. 10 is an aberration diagram of the zoom optical system according to Example 6. FIG. 10 is an aberration diagram of the zoom optical system according to Example 7. FIG. 10 is an aberration diagram of the zoom optical system according to Example 8. FIG. It is sectional drawing of an imaging device. It is a front perspective view of an imaging device. It is a back perspective view of an imaging device. It is a block diagram of the internal circuit of the main part of the imaging apparatus. It is a figure which shows the structure of a video conference system.

  Prior to the description of the examples, effects of the embodiment according to an aspect of the present invention will be described. It should be noted that, when the operational effects of the present embodiment are specifically described, a specific example will be shown and described. However, as in the case of the embodiments to be described later, those exemplified aspects are only a part of the aspects included in the present invention, and there are many variations in the aspects. 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. Regarding camera shake correction, it means that the amount of image blur caused by camera shake is less than or equal to an allowable value.

  The basic configuration of the zoom optical system of the first embodiment to the zoom optical system of the fourth embodiment (hereinafter referred to as “zoom optical system of the present embodiment”) will be described. In addition, description is abbreviate | omitted when the technical significance of the same structure has already been described. Regarding the technical significance of the conditional expression, for example, the technical significance of the conditional expression (2) is the same as the technical significance of the conditional expression (2- *) (* is a number). Explanation 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 zoom optical system according to the present embodiment includes a plurality of lens groups and an aperture stop. The plurality of lens groups includes two or more lens groups having positive refractive power and 1 having negative refractive power. Or two or more lens groups each having a positive refractive power and a positive lens group having a positive refractive power and an image side positive lens group, and having a negative refractive power. 1 or two or more lens groups having an object-side negative lens group, and the image-side positive lens group does not move along the optical axis at the time of zooming or focusing, and a plurality of lenses In the lens group, the distance from the adjacent lens group changes at the time of zooming, focusing, or zooming and focusing, and the positive lens group is a positive refraction excluding the image side positive lens group. Among the two or more lens groups having power, the image side positive lens group has the largest refractive power. Among the upper lens groups, when the lens group is located closest to the image side and the plurality of lens groups have two or more lens groups having negative refractive power, the object side negative lens group has 1 or 2 having negative refractive power. Among the above lens groups, the object side negative lens group is located closest to the object side, and the distance between the object side negative lens group and the positive lens group at the time of focusing on an object at infinity is closer to the telephoto end than to the wide angle end. The aperture stop is positioned between the lens surface closest to the image side in the object-side negative lens group and the lens surface closest to the image side in the positive lens group, or A positive lens group is adjacent to a lens surface located closest to the image side, and the image side positive lens group includes a first sub lens group having a positive refractive power, and a second sub lens including a positive lens and a negative lens. A group.

  The basic configuration includes a plurality of lens groups and an aperture stop. In the plurality of lens groups, the distance between adjacent lens groups changes at the time of zooming, focusing, or zooming and focusing.

  The plurality of lens groups includes two or more lens groups having a positive refractive power and one or more lens groups having a negative refractive power. The two or more lens groups having a positive refractive power are: One or two or more lens groups each having a positive lens group and an image side positive lens group and having a negative refractive power include an object side negative lens group.

  In the basic configuration, both the object-side negative lens group and the positive lens group are included in a plurality of lens groups. In the plurality of lens groups, there is a lens group in which an interval between adjacent lens groups is changed. Therefore, the object side negative lens group and the positive lens group can be moved. In this way, a wide angle of view can be secured at the wide angle end. In addition, the overall length of the optical system can be shortened in a wide range of the zooming range. Here, for example, a case where the half angle of view exceeds 30 degrees is referred to as a wide angle of view. However, it is not limited to this value.

  In the basic configuration, the image side positive lens group is located closest to the image side among the two or more lens groups having positive refractive power. The image side positive lens group can be arranged, for example, on the most image side among all the lens groups. If the refractive power of the lens unit located closest to the image side can be made positive, the F-number can be reduced. Here, for example, a case where the F number at the wide-angle end is 4.0 or less, or a case where the F number at the telephoto end is 5.1 or less is referred to as a small F number. However, it is not limited to this value.

  The image-side positive lens group can be prevented from moving along the optical axis at any time of zooming or focusing. In this way, the back focus can be shortened. As a result, the overall length of the optical system can be shortened. Further, the change in the F number can be reduced in a wide range of the zooming range.

  The height of the light beam incident on the second sub lens group changes during zooming. If the image side positive lens unit is fixed at the time of zooming, the second sub lens unit is also fixed. If the second sub lens group is fixed at the time of zooming, it is possible to reduce both the change in the central beam diameter incident on the second sub lens group and the change in the peripheral ray height. As a result, it becomes easy to suppress the change in lateral chromatic aberration from the wide angle end to the telephoto end, and to secure a small F number.

  The central light beam diameter is the diameter of a light beam that forms an image at the center of the image plane. The peripheral ray height is the height of a ray that forms an image on the periphery of the image plane.

  If the lens group is moved near the image plane, dust tends to be generated due to the movement of the lens group. The image side positive lens group can be positioned near the image plane. If the image-side positive lens group cannot be moved along the optical axis, the generation of dust can be reduced. When the image sensor is arranged on the image plane, it is possible to reduce adhesion of dust to the image plane.

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

  The aperture stop can be positioned between the lens surface located closest to the image side in the object side negative lens group and the lens surface located closest to the image side in the positive 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 positive lens group. By doing so, the diameter of the positive lens group does not increase even when the angle of view is widened. As a result, the optical system can be reduced in size.

  When the refractive power of each lens group is increased, the zooming effect can be increased. If the zooming action can be increased, the overall length of the optical system can be shortened and the diameter of the optical system can be reduced. However, when the zooming action is increased, it is difficult to ensure good imaging performance in a wide range of zooming when securing a small F number.

  The object side negative lens unit is involved in ensuring a wide angle of view at the wide angle end. When the zooming effect is increased, lateral chromatic aberration is likely to occur in the object-side negative lens group. Even if chromatic aberration of magnification occurs in the object side negative lens group, if the generation 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, the optical system can be made smaller, and a small F-number can be secured. realizable.

  The separation state between the on-axis light beam and the off-axis light beam at the wide-angle end is similar between the object-side negative lens group and the image-side positive lens group. Accordingly, lateral chromatic aberration is likely to occur even in the image side positive lens group. At this time, the direction of occurrence of lateral chromatic aberration in the image side positive lens group can be reversed from the direction of occurrence of lateral chromatic aberration in the object side negative lens group.

  In this way, by providing the image-side positive lens group with a magnification aberration correcting function, the magnification chromatic aberration generated in the object-side negative lens group can be corrected by the image-side positive lens group.

  In order to give the image side positive lens group a function of correcting the magnification aberration, the second sub lens group is arranged in the image side positive lens group. At this time, if the second sub lens group can be composed of a negative lens and a positive lens, lateral chromatic aberration generated in the object side negative lens group can be corrected by the image side positive lens group.

  However, astigmatism and coma aberration may occur if the lateral chromatic aberration is corrected intensively. Therefore, if only the lateral chromatic aberration is focused on, the imaging performance can be adversely affected. In this case, the first sub lens group having positive refractive power can be arranged on the object side of the second sub lens group. By doing in this way, the aberration correction capability in the whole image side positive lens group can be improved. As a result, it is possible to correct lateral chromatic aberration in the entire optical system and to correct astigmatism and coma.

  If the first sub lens group and the second sub lens group can be arranged apart from each other, the aberration correction capability of the entire image side positive lens group can be enhanced. A certain amount of air space can be provided between the first sub lens group and the second sub lens group.

  As will be described later, the first sub lens group can move in a direction orthogonal to the optical axis. In this way, camera shake correction can be performed with the first sub lens group.

  When the imaging apparatus is held by hand, the imaging apparatus 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, if vibration occurs on the fixed side, the vibration can be transmitted to the imaging device. Such vibration may be considered the same as vibration due to camera shake. Therefore, the vibration in such a case may be regarded as being included in the vibration due to camera shake.

  As described above, the lens of the image side positive lens group can be divided into a lens constituting the first sub lens group and a lens constituting the second sub lens group. If such a configuration can be adopted, lateral chromatic aberration, astigmatism, and coma can be corrected as described above. In addition, if such a configuration can be adopted, the second sub lens group can be separated from the image plane. Therefore, the magnification of the first sub lens group can be increased.

  When the magnification of the first sub lens group is increased, the ratio of the amount of movement when the lens or lens group is moved in the direction perpendicular to the optical axis and the amount of movement of the image on the image plane (hereinafter referred to as “camera shake”). Correction sensitivity ”) can be increased in the first sub lens group. For this reason, camera shake correction can be performed by the first sub lens group. As described above, when a configuration in which the image-side positive lens group is divided into two sub-lens groups can be adopted, camera shake can be corrected with a small amount of movement. In addition, since the movement amount is small, it is possible to perform camera shake correction with higher followability.

  In addition, if a lens group that performs camera shake correction is included in the lens group that moves at the time of zooming, an error may occur in the detected camera shake amount due to a change in the lens position caused by zooming. If the image side positive lens unit is fixed at the time of zooming, the second sub lens unit is also fixed. The error can be reduced by fixing the second sub lens group at the time of zooming.

The zoom optical system according to the first embodiment includes the above-described basic configuration, and the positive lens group includes a predetermined positive lens that satisfies the following conditional expression (2), and satisfies the following conditional expression (1): It is characterized by doing.
0.1 ≦ fGBUN1 / fGPM ≦ 2.1 (1)
60.8 ≦ νdGPMP1 ≦ 100.0 (2)
here,
fGBUN1 is the focal length of the first sub lens group,
fGPM is the focal length of the positive lens group,
νdGPMP1 is the Abbe number of a predetermined positive lens,
The predetermined positive lens is a positive lens having the largest Abbe number among the positive lenses in the positive lens group,
It is.

  If the lower limit of conditional expression (1) is exceeded, the occurrence of aberrations in the first sub-lens group, mainly the occurrence of coma and astigmatism, can be suppressed. As a result, good imaging performance can be obtained near the wide-angle end. If the upper limit of conditional expression (1) is not reached, the correction effect of the first sub lens unit, mainly the correction effect of coma aberration and the correction effect of astigmatism can be increased. As a result, good imaging performance can be obtained near the wide-angle end.

  If the lower limit of conditional expression (2) is exceeded, the occurrence of longitudinal chromatic aberration in the positive lens group can be suppressed. As a result, good imaging performance can be ensured in a wide range of the zooming range. If the upper limit of conditional expression (2) is not reached, chromatic aberration can be corrected well.

The zoom optical system according to the second embodiment has the above-described basic configuration and satisfies the following conditional expressions (3) and (4).
0.02 ≦ DGBUN12a / fGBUN1 ≦ 4.0 (3)
0.43 ≦ | (MGGBUN1back) × (MGGBUN1-1) | ≦ 5.0 (4)
here,
DGBUN12a is an air gap between the first sub lens group and the second sub lens group,
fGBUN1 is the focal length of the first sub lens group,
MGGBUN1 is the lateral magnification in the first sub lens group,
MGGBUN1back is the lateral magnification in a given optical system,
The predetermined optical system is an optical system composed of all lenses positioned on the image side of the first sub lens group,
The horizontal magnification is the horizontal magnification when focusing on an object at infinity,
It is.

  If the lower limit of conditional expression (3) is exceeded, the occurrence of astigmatism and coma can be suppressed.

  If the upper limit of conditional expression (3) is not reached, the thickness of the image side positive lens unit in the optical axis direction decreases. In this case, the movement space of the lens group that moves during zooming increases, and a high zoom ratio can be obtained.

  When the lower limit value of conditional expression (4) is exceeded or the upper limit value is exceeded, the occurrence of astigmatism and coma aberration can be suppressed.

  As will be described later, the first sub lens group can move in a direction orthogonal to the optical axis. In this way, camera shake correction can be performed with the first sub lens group. By exceeding the lower limit value of the conditional expression (4), it is possible to improve the camera shake correction sensitivity. In this case, since the amount of movement of the first sub lens group can be reduced, the followability of the first sub lens group with respect to camera shake can be improved.

The zoom optical system according to the third embodiment includes the above-described basic configuration, and the positive lens group includes a predetermined positive lens that satisfies the following conditional expression (2-1). It is characterized by satisfaction.
64.8 ≦ νdGPMP1 ≦ 100.0 (2-1)
-2.6 ≦ SFGBUN1 ≦ 0.95 (5)
here,
νdGPMP1 is the Abbe number of a predetermined positive lens,
The predetermined positive lens is a positive lens having the largest Abbe number among the positive lenses in the positive lens group,
SFGBUN1 is represented by the following equation:
SFGBUN1 = (RGBUN1f) + (RGBUN1r) / (RGBUN1f−RGBUN1)
RGBUN1f is the radius of curvature of the lens surface located closest to the object side of the first sub lens group,
RGBUN1r is the radius of curvature of the lens surface located closest to the image side of the first sub lens group.

  When the lower limit value of conditional expression (5) is exceeded or the upper limit value is exceeded, the occurrence of astigmatism and coma in the first sub lens group can be suppressed.

  As will be described later, camera shake correction can be performed by the first sub lens group. When the lower limit value of conditional expression (5) is exceeded or the upper limit value is exceeded, the asymmetry of spherical aberration and the astigmatism become small. Therefore, good camera shake correction performance can be obtained.

The zoom optical system according to the fourth embodiment has the above-described basic configuration, and the interval between the image-side positive lens group and the lens group located next to the image-side positive lens group changes during zooming, and the first sub- The lens surface closest to the image side of the lens group is a convex surface on the image side, and satisfies the following conditional expressions (6), (7), and (8).
2.0 ≦ fGPM / fw ≦ 20.0 (6)
2.3 ≦ fGBUN1 / fw ≦ 9.7 (7)
3.0 ≦ | LTLmax / fGN1 | ≦ 16.3 (8)
here,
fGPM is the focal length of the positive lens group,
fGBUN1 is the focal length of the first sub lens group,
fw is the focal length of the zoom optical system at the wide-angle end,
LTLmax is the maximum overall length of the zoom optical system,
fGN1 is the focal length of the object side negative lens unit,
It is.

  The distance from the lens group located next to the image side positive lens group can be changed during zooming. By doing in this way, the incident angle of the light ray which injects into an image side positive lens group can be changed. As a result, the correction effect of lateral chromatic aberration, the correction effect of astigmatism, and the correction effect of coma aberration can be enhanced in a wide range of zooming range. As a result, good imaging performance can be obtained.

  The lens surface located closest to the image side of the first sub lens group can be a convex surface on the image side. By doing so, the occurrence of coma chromatic aberration can be reduced.

  If the lower limit value of conditional expression (6) is exceeded, the occurrence of spherical aberration in the positive lens group can be mainly suppressed. As a result, a small F number can be secured at the wide angle end. If the upper limit of conditional expression (6) is not reached, the zooming effect in the positive lens group can be improved. As a result, the optical system can be reduced in size.

  By satisfying conditional expression (7), it is possible to suppress the occurrence of aberrations in the positive lens group, mainly the occurrence of coma and astigmatism.

  If the lower limit of conditional expression (8) is exceeded, the diameter of the object-side negative lens group will be reduced. As a result, the diameter of the optical unit can be reduced. If the upper limit value of conditional expression (8) is not reached, the zooming action in the positive lens group will become stronger. As a result, the diameter of the lens unit located on the image side relative to the object-side negative lens unit can be reduced. The optical unit includes, for example, a zoom optical system and a lens barrel.

  In the zoom optical system of the first embodiment to the zoom optical system of the third embodiment, the lens surface located closest to the image side of the first sub lens group can be a convex surface on the image side.

  By doing so, the occurrence of coma chromatic aberration can be reduced.

  In the zoom optical system of the first embodiment to the zoom optical system of the third embodiment, the distance between the image side positive lens group and the lens group located next to the image side positive lens group can be changed during zooming.

The zoom optical system according to the second embodiment to the zoom optical system according to the fourth embodiment can satisfy the following conditional expression (1).
0.1 ≦ fGBUN1 / fGPM ≦ 2.1 (1)
here,
fGBUN1 is the focal length of the first sub lens group,
fGPM is the focal length of the positive lens group,
It is.

In the zoom optical system of the second embodiment and the zoom optical system of the fourth embodiment, the positive lens group can include a predetermined positive lens that satisfies the following conditional expression (2-2).
60 ≦ νdGPMP1 ≦ 100.0 (2-2)
here,
νdGPMP1 is the Abbe number of a predetermined positive lens,
The predetermined positive lens is a positive lens having the largest Abbe number among the positive lenses in the positive lens group,
It is.

The zoom optical system of the first embodiment, the zoom optical system of the third embodiment, and the zoom optical system of the fourth embodiment can satisfy the following conditional expression (3).
0.02 ≦ DGBUN12a / fGBUN1 ≦ 4.0 (3)
here,
DGBUN12a is an air gap between the first sub lens group and the second sub lens group,
fGBUN1 is the focal length of the first sub lens group,
It is.

The zoom optical system of the first embodiment, the zoom optical system of the third embodiment, and the zoom optical system of the fourth embodiment can satisfy the following conditional expression (4).
0.43 ≦ | (MGGBUN1back) × (MGGBUN1-1) | ≦ 5.0 (4)
here,
MGGBUN1 is the lateral magnification in the first sub lens group,
MGGBUN1back is the lateral magnification in a given optical system,
The predetermined optical system is an optical system composed of all lenses positioned on the image side of the first sub lens group,
The horizontal magnification is the horizontal magnification when focusing on an object at infinity,
It is.

The zoom optical system of the first embodiment, the zoom optical system of the second embodiment, and the zoom optical system of the fourth embodiment can satisfy the following conditional expression (5).
-2.6 ≦ SFGBUN1 ≦ 0.95 (5)
here,
SFGBUN1 is represented by the following equation:
SFGBUN1 = (RGBUN1f) + (RGBUN1r) / (RGBUN1f−RGBUN1)
RGBUN1f is the radius of curvature of the lens surface located closest to the object side of the first sub lens group,
RGBUN1r is the radius of curvature of the lens surface located closest to the image side of the first sub lens group.

The zoom optical system of the first embodiment to the zoom optical system of the third embodiment can satisfy the following conditional expression (6).
2.0 ≦ fGPM / fw ≦ 20.0 (6)
here,
fGPM is the focal length of the positive lens group,
fw is the focal length of the zoom optical system at the wide-angle end,
It is.

The zoom optical system of the first embodiment to the zoom optical system of the third embodiment can satisfy the following conditional expression (7).
2.3 ≦ fGBUN1 / fw ≦ 9.7 (7)
here,
fGBUN1 is the focal length of the first sub lens group,
fw is the focal length of the zoom optical system at the wide-angle end,
It is.

The zoom optical system of the first embodiment to the zoom optical system of the third embodiment can satisfy the following conditional expression (8-1).
1.0 ≦ | LTLmax / fGN1 | ≦ 19.0 (8-1)
here,
LTLmax is the maximum overall length of the zoom optical system,
fGN1 is the focal length of the object side negative lens unit,
It is.

  In the zoom optical system of the present embodiment, the lens surface located closest to the object side in the first sub lens group can be a convex surface on the object side.

  By doing so, the occurrence of spherical aberration can be reduced.

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

  By doing in this way, a zooming effect can be heightened. As a result, the optical system can be miniaturized.

The zoom optical system of the present embodiment can satisfy the following conditional expression (9).
0.25 ≦ | fGN1 / fGPM | ≦ 2.0 (9)
here,
fGN1 is the focal length of the object side negative lens unit,
fGPM is the focal length of the positive lens group,
It is.

  If the lower limit of conditional expression (9) is exceeded, the occurrence of lateral chromatic aberration in the object-side negative lens group can be suppressed. If the upper limit value of conditional expression (9) is not reached, the occurrence of spherical aberration in the positive lens group can be suppressed. As a result, a small F number can be secured.

The zoom optical system according to the present embodiment can satisfy the following conditional expression (10).
1.05 ≦ | fGN1 / fw | ≦ 5.5 (10)
here,
fGN1 is the focal length of the object side negative lens unit,
fw is the focal length of the zoom optical system at the wide-angle end,
It is.

  If the lower limit of conditional expression (10) is exceeded, the occurrence of lateral chromatic aberration in the object-side negative lens group can be suppressed. If the upper limit value of conditional expression (10) is not reached, the diameter of the object side negative lens unit becomes small. As a result, the optical unit can be reduced in diameter. In addition, the amount of movement of the object side negative lens unit during zooming is reduced. As a result, zooming can be performed at high speed.

The zoom optical system of the present embodiment can satisfy the following conditional expression (11).
2.0 ≦ fGB / fw ≦ 23 (11)
here,
fGB is the focal length of the image side positive lens unit,
fw is the focal length of the zoom optical system at the wide-angle end,
It is.

  If the lower limit of conditional expression (11) is exceeded, the diameter of the image-side positive lens group can be reduced. As a result, the optical unit can be reduced in diameter. In addition, the occurrence of lateral chromatic aberration can be suppressed. If the upper limit of conditional expression (11) is not reached, it is possible to achieve both a wide angle of view and a small F number.

The zoom optical system of the present embodiment can satisfy the following conditional expression (12).
3.5 ≦ fGBUN1 / IHw35 ≦ 14.0 (12)
here,
fGBUN1 is the focal length of the first sub lens group,
IHw35 is represented by the following formula:
IHw35 = fw × tan35 °,
fw is the focal length of the zoom optical system at the wide-angle end,
It is.

  IHw35 is the distance from the position where the principal ray incident on the zoom optical system at an angle of 35 degrees intersects the paraxial image plane to the optical axis. This chief ray is the chief ray when the angle of view is 35 degrees.

  If the lower limit value of conditional expression (12) is exceeded or the upper limit value is exceeded, the occurrence of aberrations in the first sub-lens group, mainly the occurrence of coma and astigmatism, can be suppressed.

The zoom optical system of the present embodiment can satisfy the following conditional expression (13).
1.8 ≦ | fGN1 / IHw35 | ≦ 8.0 (13)
here,
fGN1 is the focal length of the object side negative lens unit,
IHw35 is represented by the following formula:
IHw35 = fw × tan35 °,
fw is the focal length of the zoom optical system at the wide-angle end,
It is.

  If the lower limit of conditional expression (13) is exceeded, the occurrence of lateral chromatic aberration in the object-side negative lens group can be suppressed. If the upper limit value of conditional expression (13) is not reached, the diameter of the object-side negative lens group decreases. As a result, the optical unit can be reduced in diameter. In addition, the amount of movement of the object side negative lens unit during zooming is reduced. As a result, zooming can be performed at high speed.

The zoom optical system of the present embodiment can satisfy the following conditional expression (14).
0.1 ≦ DGBUN12a / fw ≦ 2.0 (14)
here,
DGBUN12a is an air gap between the first sub lens group and the second sub lens group,
fw is the focal length of the zoom optical system at the wide-angle end,
It is.

  If the lower limit of conditional expression (14) is exceeded, the occurrence of astigmatism and coma can be suppressed. If the upper limit of conditional expression (14) is not reached, the thickness of the image side positive lens group in the optical axis direction decreases. In this case, the space on the object side of the image side positive lens group can be widened. When the lens group positioned on the object side of the image side positive lens group is moved along the optical axis, the moving space can be widened. As a result, a high zoom ratio can be obtained.

  In the zoom optical system of the present embodiment, the first sub lens group can be composed of lens components having no air gap.

  In this way, the thickness of the image side positive lens group in the optical axis direction can be reduced. In this case, the space on the object side of the image side positive lens group can be widened. When the lens group positioned on the object side of the image side positive lens group is moved along the optical axis, the moving space can be widened. In addition, the occurrence of high-order chromatic aberration of magnification can be suppressed.

In the zoom optical system of the present embodiment, the first sub lens group is composed of one positive lens,
The following conditional expression (15) can be satisfied.
52 ≦ νdGBUN1P ≦ 100.0 (15)
here,
νdGBUN1P is the Abbe number of the positive lens in the first sub lens group,
It is.

  When the lower limit of conditional expression (15) is exceeded, the occurrence of lateral chromatic aberration can be suppressed. Further, as will be described later, camera shake correction can be performed by the first sub lens group. When the first sub lens group is moved, the occurrence of chromatic aberration can be reduced.

  In the zoom optical system of the present embodiment, the second sub lens group can be composed of a negative lens and a positive lens.

  In this way, the thickness of the image side positive lens group in the optical axis direction can be reduced. In this case, the space on the object side of the image side positive lens group can be widened. When the lens group positioned on the object side of the image side positive lens group is moved along the optical axis, the moving space can be widened. As a result, the zoom ratio can be increased.

  In the zoom optical system of the present embodiment, the first sub lens group can be composed of one positive lens, and the second sub lens group can be composed of one negative lens and one positive lens.

  In this way, the thickness of the image side positive lens group in the optical axis direction can be reduced. In this case, the space on the object side of the image side positive lens group can be widened. When the lens group positioned on the object side of the image side positive lens group is moved along the optical axis, the moving space can be widened. As a result, it is possible to reduce the size of the optical system and secure a high zoom ratio.

  In the zoom optical system of the present embodiment, the second sub lens group can be composed of a negative lens, a positive lens, and a negative lens disposed closest to the image side.

  By doing so, it is possible to correct the lateral chromatic aberration in the image side positive lens group.

  In the zoom optical system of the present embodiment, the positive lens and the negative lens of the second sub lens group can be cemented.

  By doing in this way, generation | occurrence | production of a high-order coma aberration and generation | occurrence | production of a high-order astigmatism can be suppressed.

  In the zoom optical system of the present embodiment, the second sub lens group can be fixed at the time of zooming.

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

  If the lens group is moved near the image plane, dust tends to be generated due to the movement of the lens group. The second sub lens group is located near the image plane. Therefore, the generation of dust can be reduced by fixing the second sub lens group at the time of zooming. When the image sensor is arranged on the image plane, it is possible to reduce the adhesion of dust to the image plane.

  A lens group that moves along the optical axis at the time of focusing (hereinafter referred to as “focusing lens group”) can be disposed near the second sub lens group. If the second sub lens group is fixed at the time of zooming, the zooming actuator need not be arranged in the vicinity of the second sub lens group. Therefore, the focusing actuator can be arranged in the vicinity of the focusing lens group. As a result, the focusing unit can be reduced in size.

In the zoom optical system of the present embodiment, the second sub lens group can include a negative lens that satisfies the following conditional expression (16).
18.5 ≦ νdGBUN2N ≦ 55.0 (16)
here,
νdGBUN2N is the Abbe number of the negative lens in the second sub lens group,
It is.

  If the lower limit of conditional expression (16) is exceeded, the generation of secondary spectrum and the occurrence of lateral chromatic aberration can be suppressed.

  In the zoom optical system of the present embodiment, the aperture stop can be disposed on the object side with respect to the positive lens group.

  By doing in this way, the diameter of the lens group located on the object side from the positive lens group can be reduced.

  In the zoom optical system of the present embodiment, a moving lens group is disposed on the object side of the image-side positive lens group, and the moving lens group can move along the optical axis during zooming.

  By doing in this way, the incident angle of the light ray which injects into an image side positive lens group can be changed. As a result, the correction effect of lateral chromatic aberration, the correction effect of astigmatism, and the correction effect of coma aberration can be enhanced in a wide range of zooming range. As a result, good imaging performance can be obtained.

  The zoom optical system of the present embodiment can move the first sub lens group in a direction orthogonal to the optical axis.

  As described in the basic configuration, when the imaging apparatus is held by hand, in some cases, the imaging apparatus may vibrate due to camera shake. 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.

  The first sub lens group has a relatively small influence on the spherical aberration compared to the other lens groups. Therefore, camera shake correction can be performed by the first sub lens group. In this way, even if the lens is moved, the deterioration of the imaging performance at the center of the image can be reduced. In addition, camera shake correction sensitivity can be increased.

  The lateral chromatic aberration generated in the first sub lens group can be corrected by the second sub lens group. Therefore, it is possible to reduce the deterioration of the imaging performance at the periphery of the image.

  In the zoom optical system of the present embodiment, an intermediate lens group is disposed between the object-side negative lens group and the positive lens group, and the refractive power of the intermediate lens group in the comparison of the refractive power based on the absolute value is negative on the object side. It can be made smaller than the refractive power of the lens group and smaller than the refractive power of the positive lens group.

  When the intermediate lens group has a negative refractive power, the intermediate lens group and the object-side negative lens group can share the negative refractive power. Further, when the intermediate lens group has a positive refractive power, the intermediate lens group and the positive lens group can share the positive refractive power. In either case, the astigmatism correction capability and the spherical aberration correction capability can be mainly improved.

  Further, at the time of zooming, the distance between the intermediate lens group and the object-side negative lens group and the distance between the intermediate lens group and the positive lens group can be changed. In this way, field curvature can be corrected. As a result, good imaging performance can be obtained from the center of the image to the periphery in a wide range from the wide-angle end to the telephoto end.

  The aperture stop can be disposed between the intermediate lens group and the positive lens group. By doing in this way, the imaging performance in the periphery of an image can be made more favorable.

  In the zoom optical system of the present embodiment, the intermediate lens group can be a moving lens group, and the intermediate lens group can move along the optical axis during focusing.

  By doing so, it is possible to reduce the fluctuation of spherical aberration and the fluctuation of astigmatism during focusing. As a result, good imaging performance can be obtained.

  In the zoom optical system of the present embodiment, the object-side negative lens group and the positive lens group can be arranged adjacent to each other.

  In this case, no lens group is disposed between the object-side negative lens group and the positive lens group. Therefore, the object side negative lens group and the positive lens group can be brought closer to each other in the vicinity of the telephoto end. Thereby, zooming can be made higher.

  In the zoom optical system of the present embodiment, an image side negative lens group having negative refractive power can be disposed between the positive lens group and the image side positive lens group.

  In this way, the distance between the image side negative lens group and the positive lens group can be changed by moving the image side negative lens group along the optical axis. Thereby, good imaging performance can be obtained in a wide range of the zooming range.

  In the configuration in which the object-side negative lens group and the positive lens group are adjacent to each other, astigmatism fluctuations and field curvature fluctuations are likely to occur during zooming. By changing the distance between the image-side negative lens group and the positive lens group, it is possible to suppress fluctuations in astigmatism and field curvature that occur during zooming. As a result, even in a configuration in which the object-side negative lens group and the positive lens group are adjacent to each other, good imaging performance can be obtained in a wide range of the zooming range.

  In the zoom optical system of the present embodiment, the image-side negative lens group is a moving lens group, and can move along the optical axis during focusing.

  The image side negative lens group having a negative refractive power is disposed between a positive lens group having a positive refractive power and an image side positive lens group having a positive refractive power. At this position, the beam diameter is small. Therefore, the diameter of the image side negative lens group can be reduced. Furthermore, the magnification of the image side negative lens group can be increased. Therefore, a focusing lens group that is lightweight and has a small amount of movement during focusing can be configured. As a result, high-speed focusing can be realized.

  In the zoom optical system of the present embodiment, the image-side negative lens group can be prevented from moving along the optical axis during zooming.

  The image side negative lens group can be fixed at the time of zooming. By doing so, the number of lens groups that move during zooming can be reduced, so that the zooming mechanism can be simplified.

  In the zoom optical system of the present embodiment, the image-side negative lens group is a moving lens group, and can move along the optical axis during zooming.

  By doing so, the distance between the positive lens group and the image-side negative lens group and the distance between the image-side negative lens group and the image-side positive lens group can be changed during zooming. As a result, it is possible to suppress fluctuations in astigmatism and field curvature during zooming. In addition, the zoom ratio can be further increased.

The zoom optical system of the present embodiment can satisfy the following conditional expression (17) or (17-1).
31.9 ° ≦ ΩHw / 2 ≦ 75.0 ° (17)
31.9 ° ≦ ΩHw / 2 ≦ 88.0 ° (17-1)
here,
ΩHw is the horizontal angle of view at the wide-angle end,
It is.

  Exceeding the lower limit of conditional expression (17-1) enables wide-range imaging. Therefore, for example, even if the distance to the subject is as close as 2 m, a range having a width of about 3 m can be confirmed at a time.

  For example, when the zoom optical system of the present embodiment is used for a surveillance camera, the blind spot can be reduced. Also, the distance from the subject is difficult in an elevator or a place with a narrow road. Even in such a place, a wide range can be monitored by using the zoom optical system of the present embodiment for the monitoring camera.

  For example, when the zoom optical system of the present embodiment is used in a video conference camera, a plurality of people can be photographed at a time even in a small room. In a video conference, for example, if 1.5 m can be secured as a distance to a subject, a range having a width of about 2.3 m can be confirmed at a time. In terms of the number of people, about 5 people can be confirmed at a time. As described above, the zoom optical system of the present embodiment is effective as a zoom optical system for a video conference in a place where a large space cannot be taken.

  If the upper limit of conditional expression (17-1) is not reached, the diameter of the lens group located closer to the object side than the aperture stop can be reduced, so that the optical system can be miniaturized. In addition, since deformation at the periphery of the image is reduced, an accurate image can be obtained.

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

  In order to increase the zoom ratio and reduce the F number, it is preferable to correct spherical aberration in a wide range of wavelength regions that contribute to image formation. The third lens group located near the aperture stop can be greatly involved in spherical aberration. Therefore, spherical aberration can be corrected if at least a positive lens and a negative lens can be used in the positive lens group. When the spherical aberration is corrected, camera shake correction can be performed as described later.

  In the zoom optical system of the present embodiment, the positive lens group includes a first positive lens disposed closest to the object side and a second positive lens disposed closest to the image side, and an image of the second positive lens. The side lens surface can be a convex surface.

  By doing so, the refractive power of the positive lens group can be shared by the two positive lenses. Therefore, the refractive power of the positive lens group can be increased while suppressing the deterioration of aberration. As a result, the overall length of the optical system can be shortened and the F number can be reduced.

  By increasing the refractive power of the first positive lens, the zooming effect in the positive lens group can be increased. By making the lens surface on the image side of the second positive lens convex, it is possible to enhance the spherical aberration correction effect and the coma aberration correction effect.

  In the zoom optical system of the present embodiment, the total length of the zoom optical system can be made constant during zooming.

  If 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. If the position of the center of gravity of the entire optical system changes, the posture at the time of shooting 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 take a picture in a fixed posture.

  If the overall length of the zoom optical system can be made constant during zooming, the lens group located closest to the object side during zooming can be prevented from moving. If the lens group located closest to the object side during zooming can be prevented from moving, zooming can be performed with less change in posture during shooting.

  Further, in terms of appearance, there is no movable part in the lens barrel. Therefore, when an optical unit is configured using the zoom optical system and the lens barrel of the present embodiment, an optical unit with 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.

  In the zoom optical system of the present embodiment, at the time of zooming, the aperture stop can be moved only in one direction along the optical axis or can be prevented from moving.

  At the time of zooming, the aperture stop can move along the optical axis. If the moving direction 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 is caused by backlash in a moving mechanism using a gear, for example. By changing the moving direction of the aperture stop to only one direction at the time of zooming, the position of the aperture stop can always be stabilized. The F number changes with zooming. If 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, the error when changing the F number can be reduced.

  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.

  In the zoom optical system of the present embodiment, the aperture stop can be prevented from moving along the optical axis during zooming.

  If the aperture stop is fixed at the time of zooming, the rapid change of the F number due to zooming can be reduced. As a result, even when the F number is small, it is possible to secure a stable light amount over a wide range of zooming range.

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

  In the zoom optical system of the present embodiment, a predetermined positive lens group having a positive refractive power can be disposed on the object side of the object-side negative lens group.

  In this case, a lens group having a positive refractive power (predetermined positive lens group, image side positive lens group) is arranged on the object side and the image side of the positive lens group. Therefore, it becomes easy to adopt an optically symmetric configuration around the positive lens group in the wide zoom range and the entire zoom range. As a result, a wide angle of view and a high zoom ratio at the wide angle end can be ensured. Furthermore, the overall length of the optical system can be shortened, and it is possible to satisfactorily correct mainly field curvature and coma aberration in a wide range of zooming range. An optically symmetric configuration is, for example, an array of refractive powers.

  A telephoto type optical system can be configured by the predetermined positive lens group and the object-side negative lens group. In this case, the distance between the predetermined positive lens group and the object-side negative lens group can be made wider at the telephoto end than at the wide angle end. By doing in this way, the effect | action which a telephoto type has can be strengthened. As a result, the overall length of the optical system can be shortened and the zoom ratio can be increased.

  The predetermined positive lens group can be disposed closest to the object side. By doing in this way, the effect | action which a telephoto type has can be strengthened more. As a result, the overall length of the optical system can be shortened and the zoom ratio can be increased.

  Since the diameter of the light beam incident on the positive lens group can be reduced, the diameter of the positive lens group can be reduced even if the F number near the telephoto end is reduced.

  As described above, in a zoom optical system having a wide angle of view and a high zoom ratio, it is possible to obtain an optical system that is small and can ensure good imaging performance.

The zoom optical system of the present embodiment can satisfy the following conditional expression (18).
2.3 ≦ fGP1 / fGPM ≦ 7 (18)
here,
fGP1 is a focal length of a predetermined positive lens group,
fGPM is the focal length of the positive lens group,
It is.

  If the lower limit of conditional expression (18) is exceeded, the zooming action in the positive lens group can be strengthened. As a result, a high zoom ratio can be obtained. If the upper limit of conditional expression (18) is not reached, the occurrence of spherical aberration and coma in the positive lens group can be suppressed. As a result, a small F number is obtained.

  In the zoom optical system of the present embodiment, the predetermined positive lens group includes a negative lens and a positive lens, the positive lens of the predetermined positive lens group is a meniscus lens, and the lens surface on the object side of the meniscus lens is The surface can be convex to the object side.

  The predetermined positive lens group can include a negative lens and a positive lens. As a result, a high zoom ratio can be realized, and the occurrence of chromatic aberration can be reduced over a wide range of the zoom range.

  The positive lens of the predetermined positive lens group can be a meniscus lens. The lens surface on the object side of the meniscus lens can be a convex surface on the object side. By doing so, the fluctuation of astigmatism at the time of zooming can be reduced. As a result, stable imaging performance can be obtained in a wide range of the zooming range.

  In the zoom optical system of the present embodiment, the predetermined positive lens group can be composed of a negative lens and two positive lenses.

  In a predetermined positive lens group, spherical aberration tends to occur near the telephoto end. By doing so, it is possible to suppress the occurrence of spherical aberration near the telephoto end. As a result, a high zoom ratio can be obtained.

  Of the two positive lenses, at least one positive lens can be a positive meniscus lens having a convex surface facing the object side. By doing in this way, the fluctuation | variation of astigmatism can be reduced with the fluctuation | variation of the spherical aberration at the time of zooming. As a result, stable imaging performance can be obtained in a wide range of the zooming range.

  In the zoom optical system of the present embodiment, the two positive lenses in the predetermined positive lens group are both meniscus lenses, and the lens surface on the object side of the meniscus lens can be a convex surface on the object side.

  As a result, a high zoom ratio can be realized, and the occurrence of chromatic aberration can be reduced over a wide range of the zoom range. In addition, the fluctuation of astigmatism at the time of zooming can be reduced. As a result, stable imaging performance can be obtained in a wide range of the zooming range.

  In the zoom optical system according to the present embodiment, the predetermined positive lens group can further include another positive lens.

  By doing so, the positive refractive power in the predetermined positive lens group can be increased. As a result, the overall length of the optical system can be shortened.

The zoom optical system of the present embodiment can satisfy the following conditional expression (19).
0.5 ≦ | fGPM / fGNB | ≦ 2.0 (19)
here,
fGPM is the focal length of the positive lens group,
fGNB is a focal length of the image side negative lens unit,
It is.

  If the lower limit of conditional expression (19) is exceeded, the occurrence of curvature of field in the image side negative lens unit can be suppressed. If the upper limit of conditional expression (19) is not reached, the occurrence of astigmatism in the image side negative lens unit can be suppressed. As a result, it is possible to prevent the image from being in one-sided blur due to assembly errors.

The zoom optical system of the present embodiment can satisfy the following conditional expression (20).
0.25 ≦ fGN1 / fGNB ≦ 1.5 (20)
here,
fGN1 is the focal length of the object side negative lens unit,
fGNB is a focal length of the image side negative lens unit,
It is.

  If the lower limit of conditional expression (20) is exceeded, the occurrence of lateral chromatic aberration due to the object-side negative lens group can be suppressed. If the upper limit of conditional expression (20) is exceeded, the zooming effect in the object-side negative lens group can be strengthened.

The zoom optical system of the present embodiment can satisfy the following conditional expression (21).
0.03 ≦ ΔGPMM / LTLw ≦ 0.3 (21)
here,
ΔGPMM is the amount of movement of the positive lens group when moving from the wide-angle end to the telephoto end.
LTLw is the total length of the zoom optical system at the wide-angle end,
It is.

  If the lower limit of conditional expression (21) is exceeded, the zooming action in the lens group can be dispersed in the object-side negative lens group. As a result, even when the angle of view at the wide angle end of the wide angle of view is wide, fluctuations in lateral chromatic aberration can be suppressed.

  If the upper limit of conditional expression (21) is not reached, the amount of movement of the positive lens group can be reduced. As a result, the zooming speed is improved. Further, even when the F number near the telephoto end is reduced, the diameter of the positive lens group can be reduced and the occurrence of spherical aberration can be suppressed.

  In the zoom optical system of the present embodiment, the positive lens group can be prevented from moving along the optical axis during zooming.

  When the lens group is moved, the position when the lens group is stopped may vary due to the play of the moving mechanism. The positive lens group can be involved in the generation of spherical aberration and coma. Therefore, the positive lens group is fixed at the time of zooming. By doing in this way, about the position of a positive lens group, the shift | offset | difference from a design position can be suppressed in the wide range of a zooming range. As a result, good imaging performance can be obtained in a wide range of the zooming range.

  Near the telephoto end, the amount of spherical aberration and the amount of coma are likely to increase. In an optical system in which the half angle of view at the telephoto end is 4 degrees or less, if the positive lens group can be fixed at the time of zooming, it is effective for suppressing the occurrence of these aberrations.

  In the zoom optical system of the present embodiment, the object side negative lens group can be disposed closest to the object side.

  By doing so, it is possible to secure a wider angle of view.

In the zoom optical system of the present embodiment, the object-side negative lens group includes a first negative meniscus lens, a second negative meniscus lens, and one positive lens, and the first negative meniscus lens is The second negative meniscus lens located closest to the object side is located on the image side of the first negative meniscus lens, the lens surface on the object side of the first negative meniscus lens, and the lens on the object side of the second negative meniscus lens. Both surfaces can be concave on the image side.
On the most object side

  The negative refractive power of the object-side negative lens unit is greatly involved in reducing the diameter of the optical system. By increasing the negative refractive power of the object-side negative lens group, the diameter of the optical system can be reduced. In addition, the angle of view can be widened.

  When the negative refractive power of the object side negative lens unit is increased, the amount of curvature of field and the amount of astigmatism are likely to increase. In the lens group located closest to the object side, the height when the off-axis principal ray passes through the lens group is the highest.

  Therefore, the first negative meniscus lens is disposed closest to the object side of the object side negative lens group. Then, the second negative meniscus lens is disposed on the image side of the first negative meniscus lens. The object-side lens surface of the first negative meniscus lens and the object-side lens surface of the second negative meniscus lens are both concave on the image side. If it can do in this way, rapid refraction of light rays can be reduced while increasing the negative refractive power of the object side negative lens group. As a result, the occurrence of field curvature and astigmatism can be reduced. Further, by arranging a positive lens, it is possible to reduce the occurrence of longitudinal chromatic aberration and lateral chromatic aberration.

  In the zoom optical system of the present embodiment, the intermediate lens group has a positive refractive power and can be disposed on the object side of the aperture stop.

  In this way, it is possible to secure a wide angle of view by increasing the negative refractive power of the object side negative lens group, and at the same time, it is possible to correct lateral chromatic aberration that tends to occur by widening the angle of view.

The zoom optical system of the present embodiment can satisfy the following conditional expression (22).
7.0 ≦ ft / fw ≦ 120 (22)
here,
ft is the focal length of the zoom optical system at the telephoto end,
fw is the focal length of the zoom optical system at the wide-angle end,
It is.

  If the lower limit of conditional expression (22) is exceeded, a high-definition image can be obtained. Therefore, for example, when the zoom optical system according to the present embodiment is used for a surveillance camera, it is possible to clearly photograph an automobile license plate, a human face, and the like. If the upper limit of conditional expression (22) is not reached, the total length of the optical system can be shortened. As a result, the optical system can be reduced in size.

The zoom optical system of the present embodiment can satisfy the following conditional expression (23).
0.6 ≦ FNOw ≦ 4.0 (23)
here,
FNOw is the F number at the wide-angle end,
It is.

  If the lower limit value of conditional expression (23) is exceeded, the occurrence of spherical aberration and astigmatism near the wide-angle end can be suppressed in each of the object-side negative lens group and the positive lens group. Further, even in a predetermined positive lens group, it is possible to suppress the occurrence of spherical aberration and astigmatism near the wide-angle end.

  If the upper limit of conditional expression (23) is not reached, sufficient brightness can be secured at the wide-angle end. Therefore, for example, when the zoom optical system of the present embodiment is used for a monitoring camera, a good image can be obtained by monitoring in cloudy weather or monitoring at night.

The zoom optical system of the present embodiment can satisfy the following conditional expression (24).
0.7 ≦ FNOt ≦ 5.1 (24)
here,
FNOt is the F number at the telephoto end.
It is.

  If the lower limit of conditional expression (24) is exceeded, the occurrence of spherical aberration and astigmatism near the telephoto end can be suppressed in each of the object-side negative lens group and the positive lens group. Further, even in a predetermined positive lens group, it is possible to suppress the occurrence of spherical aberration and astigmatism near the telephoto end.

  If the upper limit of conditional expression (24) is not reached, sufficient brightness can be secured at the telephoto end. Therefore, for example, when the zoom optical system of the present embodiment is used for a monitoring camera, a good image can be obtained by monitoring in cloudy weather or monitoring at night.

The zoom optical system of the present embodiment can satisfy the following conditional expression (25) or (25-1).
0.0 ≦ ft / fw + 13.38 × tan (ΩHw / 2) −21.0 ≦ 80 (25)
0.0 ≦ ft / fw + 13.38 × tan (ΩHw / 2) −21.0 ≦ 350 (25-1)
here,
fw is the focal length of the zoom optical system at the wide-angle end,
ft is the focal length of the zoom optical system at the telephoto end,
ΩHw is the horizontal angle of view at the wide-angle end,
It is.

  For example, in a surveillance camera, the visual field range at the wide-angle end may be confirmed, or the predetermined area may be enlarged to confirm in detail the predetermined area. When considering more detailed information, the zoom ratio may be increased.

  In the zoom 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 can be reduced in proportion to the tan of the angle of view. That is, the reduction rate of the information amount is equal to or higher than the change rate of the angle of view.

  If 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 the case where the horizontal angle of view at the wide-angle end is wide. Is possible. In a surveillance camera, the larger the amount of information obtained by imaging, the better. In surveillance camera applications, the amount of information can be compensated by narrowing the angle of view at the telephoto end.

  If the lower limit of conditional expression (25-1) is exceeded, a sufficient amount of information can be obtained. If the lower limit of conditional expression (25-1) is not reached, the diameter of the object-side negative lens group can be reduced, and the optical system can be made smaller. Alternatively, the occurrence of astigmatism in the object side negative lens unit can be reduced.

The zoom optical system of the present embodiment can satisfy the following conditional expression (26).
0.04 ≦ ΣGP1 / LTLw ≦ 0.35 (26)
here,
ΣGP1 is the thickness of a predetermined positive lens group,
LTLw is the total length of the zoom optical system at the wide-angle end,
It is.

  If the lower limit of conditional expression (26) is exceeded, the refractive power of the predetermined positive lens group can be increased. As a result, the overall length of the optical system can be shortened. If the upper limit of conditional expression (26) is not reached, it is possible to secure a space for moving the lens group located next to the predetermined positive lens group at the time of zooming. Therefore, high zooming can be ensured while securing a wide angle of view on the wide angle side.

The zoom optical system of the present embodiment can satisfy the following conditional expression (27).
−2.3 <fw × FNOw / fGN1 <−0.4 (27)
here,
fw is the focal length of the zoom optical system at the wide-angle end,
FNOw is the F number at the wide-angle end,
fGN1 is the focal length of the object side negative lens unit,
It is.

  If the lower limit of conditional expression (27) is exceeded, a wide angle of view can be obtained even when a small F number is obtained while reducing the diameter of the optical system. When the upper limit of conditional expression (27) is not reached, the optical system can be reduced in diameter.

The zoom optical system of the present embodiment can satisfy the following conditional expression (28).
1.9 <SPGN1Ln1 <6.5 (28)
here,
SPGN1Ln1 is represented by the following equation:
SPGN1Ln1 = (RGN1Ln1f + RGN1Ln1r) / (RGN1Ln1f−RGN1Ln1r)
RGN1Ln1f is the radius of curvature of the object-side lens surface of the first negative meniscus lens,
RGN1Ln1r is the radius of curvature of the lens surface on the image side of the first negative meniscus lens,
It is.

  Below the lower limit of conditional expression (28), the difference in curvature between the object-side lens surface and the image-side lens surface becomes too large. As a result, astigmatism occurs.

  When the upper limit of conditional expression (28) is exceeded, the difference in curvature between the object-side lens surface and the image-side lens surface becomes too small. Therefore, the refractive power of the object side negative lens unit becomes small. In this case, the incident height of the light incident on the lens group located on the image side is higher than that on the object side negative lens group. As a result, the diameter of the lens unit positioned on the image side is larger than that of the object-side negative lens unit.

  If the negative refractive power of the object side negative lens unit is forcibly increased to reduce the diameter of the optical system while exceeding the upper limit value of conditional expression (28), the curvature of the lens surface of the first negative meniscus lens will be reduced. Too much. In this case, since the top of the object side surface protrudes toward the object side, the entire length of the optical system is increased and the diameter including the lens frame is increased.

The zoom optical system of the present embodiment can satisfy the following conditional expression (29).
-25% <DTw <5% (29)
here,
DTw is the amount of distortion at the maximum angle of view at the wide-angle end, and is expressed by the following equation:
DTw = (IHw1-IHw2) / IHw2 × 100 (%),
IHw1 is a real image height when a light beam including a light beam having a maximum angle of view forms an image on the image plane,
IHw2 is a paraxial image height when a light beam including a light beam having a maximum angle of view forms an image on the image plane,
In both cases, the image height when focusing on an object point at infinity
It is.

  If the lower limit value of conditional expression (29) is not reached, the distortion of the image becomes too large. This makes it difficult to accurately recognize the subject. Alternatively, when the image obtained by the imaging apparatus is electrically distorted, the peripheral portion of the image is greatly stretched, so that the image in the peripheral portion is significantly deteriorated.

  If the upper limit of conditional expression (29) is exceeded, the angle of view becomes too narrow than the angle of view in the non-aberration state. Therefore, a sufficient amount of information cannot be obtained at the wide angle end.

  The image pickup apparatus of the present embodiment includes an optical system and an image pickup element that has an image pickup surface and converts an image formed on the image pickup surface by the optical system into an electric signal, and the optical system is the zoom of the present embodiment. It is an optical system.

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

The zoom optical system of the present embodiment can satisfy the following conditional expression (30).
3.15 mm ≦ Rimg ≦ 40.0 mm (30)
here,
Rimg is the radius of the image circle in the image sensor,
It is.

  The optical system used in the surveillance camera can have a high resolution in order to ensure 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 resolution, the number of pixels of the image sensor is preferably at least 2.5 million pixels, 3 million images or more, or 8 million pixels, for example.

  If the lower limit of conditional expression (30) is exceeded, the pixel pitch will not be too small even if a high resolution is secured. Therefore, the sensitivity of the image sensor can be kept high. If the upper limit of conditional expression (30) is not reached, the imaging device can be downsized.

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

  For example, there may be two shooting needs in the shooting needs of a digital camera or a video camera. The first shooting needs are the need to shoot a large building and the need to take a commemorative photo with a vast background. The second shooting need is a need to perform from a wide range of shooting to a magnified shooting of a subject with one shooting lens.

  In order not to miss the photographing opportunity, it is preferable that a high-resolution image is stably obtained. For this purpose, it is only necessary to improve the imaging performance of the optical system and stabilize the imaging performance. By doing so, a high-resolution image can be stably formed.

  When vibration due to camera shake or vibration other than camera shake occurs, image blurring occurs. When image blurring occurs, it becomes difficult to stably obtain a high-resolution image. In order to stably obtain a high-resolution image, it is only necessary to suppress image blur due to vibration as much as possible.

  Image blur due to vibration can be suppressed by reducing the open F number. If a part of the optical system can be moved, image blur due to vibration can be corrected.

  In order not to miss the shooting opportunity, it is only necessary to be able to zoom quickly.

  As a need for a surveillance camera, it may be possible to monitor a wider range or to monitor at a higher magnification. For example, monitoring at a higher magnification can easily identify the number on the license plate or the person.

  In digital cameras and video cameras, mobility may be important. Here, mobility refers to, for example, ease of carrying, stability during hand-held shooting, and high speed of focus speed. In order to improve the mobility of the apparatus, the optical system may be small and light. In addition, in a surveillance camera, the location where the surveillance camera is installed may be limited. Therefore, there are cases where the optical system is required to be reduced in size and diameter.

The zoom optical system according to the present embodiment can be used mainly for an optical system of an imaging apparatus 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, and further 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 36 degrees or more 29 mm or less 40 degrees or more 26 mm or less 42 degrees or more 24 mm or less

  The zoom optical system of this embodiment can ensure a wide angle of view at the wide-angle end and a small F number, and can correct various aberrations satisfactorily. Further, the zoom 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 zoom 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 a shooting opportunity.

  The zoom optical system and optical device described above can satisfy a plurality of configurations at the same time. By doing in this way, a favorable zoom optical system and optical device can be obtained. Moreover, the combination of a structure is arbitrary. For each conditional expression, only the upper limit value or lower limit value of the numerical range of the more limited conditional expression can be limited.

  At least one of conditional expressions (9) to (30) can be combined with the basic configuration of the zoom optical system according to the present embodiment. In this combination, conditional expressions (1), (2), (2-1), and (3) to (8) can be excluded.

About each conditional expression, a lower limit or an upper limit can be changed as follows.
Conditional expression (1) is as follows.
The lower limit value can be set to 0.26, 0.3, 0.4, 0.42, 0.5, 0.58, 0.6, or 0.75.
The upper limit value can be any of 2.0, 1.8, 1.7, 1.6, 1.56, and 1.4.
Conditional expressions (2), (2-1), and (2-2) are as follows.
The lower limit value can be any of 61, 63, 64, 65, 66, 69, 70, 71, 73, 74, 76, 77, and 80.
The upper limit value can be any one of 95, 91, and 86.
Conditional expression (3) is as follows.
The lower limit value can be any of 0.025, 0.03, 0.035, and 0.04.
The upper limit value can be any of 3.0, 2.1, 1.1, 0.5, 0.4, 0.3, 0.2, and 0.17.
Conditional expression (4) is as follows.
The lower limit value can be any of 0.44, 0.45, 0.47, 0.5, 0.52, 0.55, 0.56, 0.6, and 0.61.
The upper limit value can be any of 4.0, 3.0, 2.9, 2.0, 1.9, 1.5, 1.2, 1.0, and 0.80.
Conditional expression (5) is as follows.
Lower limit value is -2.2, -2.0, -1.8, -1.5, -1.4, -1.0, -0.97, -0.8, -0.7 Can be.
The upper limit value can be any of 0.8, 0.70, 0.5, 0.44, 0.3, 0.19, 0.0, -0.07, and -0.3.
Conditional expression (6) is as follows.
The lower limit value can be any of 2.2, 2.3, 2.4, 2.5, 2.6, 2.7, 2.9, 3.4, 3.6.
The upper limit value can be any of 16.4, 12.7, 10.0, 9.1, 9.0, 8.0, 7.0, 5.5.
Conditional expression (7) is as follows.
The lower limit value can be any of 2.5, 2.6, 2.8, 2.9, 3.5, 4.0, and 4.5.
The upper limit value can be any of 9.0, 8.7, 8.5, 8.0, 7.8, 7.0, 6.8, 6.5, 5.9.
Conditional expressions (8) and (8-1) are as follows.
The lower limit is 2.0, 3.2, 4.0, 4.7, 5.0, 5.4, 6.0, 6.4, 7.0, 7.5, 7.7, 8.0. , 8.2, 8.5, 9.0, or 9.9.
Upper limit is 18.1, 18.0, 17.5, 17.2, 17.0, 16.5, 16.3, 16.1, 16.0, 15.8, 15.6, 15.5 , 15.3, 15.0, 14.5, or 14.0.
Conditional expression (9) is as follows.
The lower limit value can be any of 0.26, 0.27, 0.28, 0.29, 0.30, 0.4, and 0.45.
The upper limit value can be set to 1.7, 1.5, 1.4, 1.3, 1.2, 1.0, or 0.70.
Conditional expression (10) is as follows.
The lower limit value can be any one of 1.1, 1.15, 1.2, 1.3, 1.4, 1.5, 2.1, and 2.5.
The upper limit value can be any of 5.0, 4.7, 4.5, 4.3, 4.1, 4.0, and 3.5.
Conditional expression (11) is as follows.
The lower limit value can be any one of 2.2, 2.3, 2.4, 2.5, 2.6, 2.7, 2.8, and 3.05.
The upper limit value can be any of 21.5, 20.9, 20, 19, 18.8, 18, 16.7, and 14.56.
Conditional expression (12) is as follows.
The lower limit value can be any of 3.7, 3.8, 4.0, 4.2, 4.5, and 5.0.
The upper limit value can be any of 13.0, 12.6, 12.0, 11.2, 10.0, 9.8, and 8.4.
Conditional expression (13) is as follows.
The lower limit value can be any one of 1.8, 1.9, 2.1, 3.0, and 3.5.
The upper limit value can be any of 7.3, 7.0, 6.7, 6.5, 6.0, 5.8, and 5.1.
Conditional expression (14) is as follows.
The lower limit value can be any one of 0.12, 0.13, 0.14, 0.15, 0.16, and 0.18.
The upper limit value can be any of 1.7, 1.5, 1.2, and 0.97.
Conditional expression (15) is as follows.
The lower limit value can be any of 52, 53, 55, 59, 63, and 67.
The upper limit value can be any of 95, 91, 86, and 82.
Conditional expression (16) is as follows.
The lower limit value can be any one of 20, 21, 23, 24, 25, 26, 27, 28, and 29.
The upper limit value can be any of 55, 54, 53, 53.5, 50, and 45.
The conditional expressions (17) and (17-1) are as follows (the unit is “° (degree)”).
The lower limit value can be any of 32, 33, 36, 37, 39, 41, and 48.
The upper limit value can be any one of 85, 80, 75, 70, 66, 65, 61, and 56.
Conditional expression (18) is as follows.
The lower limit value can be any of 2.5, 2.6, 2.7, 2.8, 2.9, 3.0, and 3.2.
The upper limit value can be any of 6.5, 6.2, 6.0, 5.5, 5.3, 5.0, 4.5, 4.0, 3.6.
Conditional expression (19) is as follows.
The lower limit value can be any of 0.63, 0.7, 0.76, 0.85, 0.89, and 1.0.
The upper limit value can be any one of 1.8, 1.7, 1.6, 1.5, 1.4, and 1.3.
Conditional expression (20) is as follows.
The lower limit value can be any of 0.31, 0.35, 0.37, 0.4, 0.42, 0.45, and 0.48.
The upper limit value can be any one of 1.34, 1.2, 1.1, 1.0, and 0.84.
Conditional expression (21) is as follows.
The lower limit value can be any of 0.05, 0.06, 0.09, 0.1, 0.11, 0.13, and 0.14.
The upper limit value can be any of 0.28, 0.25, 0.23, 0.22, and 0.20.
Conditional expression (22) is as follows.
The lower limit value can be any of 8.7, 9.5, 10.4, 12, 12.1, 13.5, 13.7, 14, and 20.
The upper limit value can be any one of 100, 81, 80, 63, 60, 45, 44, and 25.
Conditional expression (23) is as follows.
The lower limit value can be any one of 0.77, 0.8, 0.85, 0.9, 1.0, 1.1, 1.2, and 1.3.
Upper limit is 3.7, 3.5, 3.4, 3.2, 3.0, 2.9, 2.6, 2.5, 2.4, 2.2, 2.0, 1.84 It can be either 1.8.
Conditional expression (24) is as follows.
The lower limit value can be any of 1.2, 1.25, 1.5, 1.7, 1.79, 2.0, 2.2, 2.34, and 2.88.
Upper limit is 5.0, 4.80, 4.7, 4.51, 4.5, 4.3, 4.21, 4.2, 4.0, 3.91, 3.5, 2.95. Can be either.
Conditional expressions (25) and (25-1) are as follows.
The lower limit value can be any one of 0.13, 0.2, 0.26, 0.3, 0.39, 0.45, 0.52, 1.0, and 3.5.
The upper limit value can be any one of 300, 150, 80, 70, 63, 60, 50, 46, 45, 40, 35, 30, 25, 20, and 13.
Conditional expression (26) is as follows.
The lower limit value can be any of 0.05, 0.07, 0.08, and 0.10.
The upper limit value can be any of 0.31, 0.26, 0.22, and 0.18.
Conditional expression (27) is as follows.
The lower limit value can be any of -2.2, -2.1, -1.9, -1.8, -1.7, -1.6, and -1.55.
The upper limit value can be any one of -0.42, -0.43, -0.45, -0.46, -0.5, -0.6, -0.8, and -1.0. .
Conditional expression (28) is as follows.
The lower limit value can be any of 2.5, 2.6, 3.0, 3.2, 3.9, 4.0, and 4.5.
The upper limit value can be any of 6.1, 6.0, 5.8, 5.7, 5.5, 5.4, 5.0.
The conditional expression (29) is as follows (the unit is “%”).
The lower limit value can be any of -23, -22.0, -21, -20.0, -18, -17.0, -16.5, -16, and -15.0.
Upper limit is 4.5, 4.0, 3.0, 2.8, 2.5, 0.68, 0, -1.5, -3.0, -3.5, -3.6 Can be crab.
The conditional expression (30) is as follows (unit: “mm”).
The lower limit can be any of 3.2, 3.25, 3.3, 3.4, 3.5, 3.6, 3.8, 4.0, 4.1, 5.0. .
The upper limit value can be any of 38, 35, 33, 26, 19, and 12.

  Embodiments of the zoom optical system will be described below in detail with reference to the drawings. Note that the present invention is not limited to the embodiments.

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

  An aberration diagram of each example 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 (DT). 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 aberration (DT) in the intermediate focal length state, (h) ) Shows lateral chromatic aberration (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, the image plane (imaging plane) is indicated by I. Further, a cover glass C of the image sensor can be disposed between the lens group located closest to the image side and the image plane I.

Each of the above-described “predetermined positive lens group”, “object side negative lens group”, “intermediate lens group”, “positive lens group”, “image side negative lens group”, and “image side positive lens group” Table 1 shows the relationship between the first lens group G1 to the sixth lens group G6.

  The zoom optical system of Example 1 includes, in order from the object side, a first lens group G1 having a negative refractive power, a second lens group G2 having a positive refractive power, and a third lens group having a positive refractive power. G3 and a fourth lens group G4 having a positive refractive power. The aperture stop S is disposed 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 negative meniscus lens L2 having a convex surface facing the object side, a negative meniscus lens L3 having a convex surface facing the object side, and a biconcave negative lens. L4 and a positive meniscus lens L5 having a convex surface facing the object side.

  The second lens group G2 includes a negative meniscus lens L6 having a convex surface directed toward the object side, and a biconvex positive lens L7. Here, the negative meniscus lens L6 and the biconvex positive lens L7 are cemented.

  The third lens group G3 includes a positive meniscus lens L8 having a convex surface directed toward the image side, a biconcave negative lens L9, a biconvex positive lens L10, a biconcave negative lens L11, a biconvex positive lens L12, and an object side. And a negative meniscus lens L13 having a convex surface facing the surface, and a biconvex positive lens L14. Here, the negative meniscus lens L13 and the biconvex positive lens L14 are cemented.

  The fourth lens group G4 includes a biconvex positive lens L15, a biconcave negative lens L16, a biconvex positive lens L17, and a negative meniscus lens L18 having a convex surface directed toward the object side. Here, the biconcave negative lens L16 and the biconvex positive lens L17 are cemented.

  The first sub lens group includes a biconvex positive lens L15. The second sub lens group includes a biconcave negative lens L16, a biconvex positive lens L17, and a negative meniscus lens L18.

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

  During focusing, the second lens group G2 moves along the optical axis. During camera shake correction, the biconvex positive lens L15 moves in a direction perpendicular to the optical axis.

  The aspheric surfaces are provided on a total of six surfaces including both side surfaces of the negative meniscus lens L2, both side surfaces of the biconvex positive lens L12, the object side surface of the biconvex positive lens L15, and the image side surface of the negative meniscus lens L18. Yes.

  The zoom optical system of Example 2 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 group having a positive refractive power. G3 includes a fourth lens group G4 having a negative refractive power and a fifth lens group G5 having a positive refractive power. The aperture stop S is disposed 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. Yes. Here, the negative meniscus lens L1 and the positive meniscus lens L2 are cemented.

  The second lens group G2 includes a negative meniscus lens L4 having a convex surface directed toward 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 directed toward the object side, and a biconvex positive lens L9. Here, the negative meniscus lens L8 and the biconvex positive lens L9 are cemented.

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

  The fifth lens group G5 includes a biconvex positive lens L11, a negative meniscus lens L12 having a convex surface directed toward the object side, and a biconvex positive lens L13. Here, the negative meniscus lens L12 and the biconvex positive lens L13 are cemented.

  The first sub lens group includes a biconvex positive lens L11. The second sub lens group is composed of a negative meniscus lens L12 and a biconvex positive lens L13.

  At the time of zooming, the first lens group G1 moves to the image side, 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 The group G4 and the fifth lens group G5 are fixed. The aperture stop S is fixed.

  During focusing, the fourth lens group G4 moves along the optical axis. During camera shake correction, the biconvex positive lens L11 moves in a direction perpendicular to the optical axis.

  The aspheric surfaces are provided on a total of eight surfaces including both side surfaces of the biconcave negative lens L5, both side surfaces of the biconvex positive lens L7, both side surfaces of the biconcave negative lens L10, and both side surfaces of the biconvex positive lens L11. It has been.

  The zoom optical system of Example 3 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 group having a positive refractive power. G3 includes a fourth lens group G4 having a negative refractive power and a fifth lens group G5 having a positive refractive power. The aperture stop S is disposed 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. Yes. Here, the negative meniscus lens L1 and the positive meniscus lens L2 are cemented.

  The second lens group G2 includes a negative meniscus lens L4 having a convex surface directed toward 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 directed toward the object side, and a biconvex positive lens L9. Here, the negative meniscus lens L8 and the biconvex positive lens L9 are cemented.

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

  The fifth lens group G5 includes a biconvex positive lens L11, a negative meniscus lens L12 having a convex surface on the image side, a negative meniscus lens L13 having a convex surface on the object side, and a biconvex positive lens L14. ing. Here, the biconvex positive lens L11 and the negative meniscus lens L12 are cemented. The negative meniscus lens L13 and the biconvex positive lens L14 are cemented.

  The first sub lens group includes a biconvex positive lens L11 and a negative meniscus lens L12. The second sub lens group is composed of a negative meniscus lens L13 and a biconvex positive lens L14.

  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, and the fourth lens group G4 moves to the object side. Moving to the image side, the fifth lens group G5 is fixed. The aperture stop S is fixed.

  During focusing, the fourth lens group G4 moves along the optical axis. During camera shake correction, the biconvex positive lens L11 and the negative meniscus lens L12 move in a direction perpendicular to the optical axis.

  The aspheric surfaces are provided on a total of seven surfaces including both side surfaces of the biconcave negative lens L5, both side surfaces of the biconvex positive lens L7, both side surfaces of the biconcave negative lens L10, and the object side surface of the biconvex positive lens L11. It has been.

  The zoom optical system of Embodiment 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 group having a negative refractive power. G3 includes a fourth lens group G4 having a positive refractive power, a fifth lens group G5 having a negative refractive power, and a sixth lens group G6 having a positive refractive power. The aperture stop S is disposed between the third lens group G3 and the fourth lens group G4.

  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. Yes. Here, the negative meniscus lens L1 and the positive meniscus lens L2 are cemented.

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

  The third lens group G3 includes a negative meniscus lens L7 having a convex surface directed toward the image side.

  The fourth lens group G4 includes a biconvex positive lens L8, a negative meniscus lens L9 having a convex surface directed toward the object side, and a biconvex positive lens L10. Here, the negative meniscus lens L9 and the biconvex positive lens L10 are cemented.

  The fifth lens group G5 is composed of a biconcave negative lens L11.

  The sixth lens group G6 includes a biconvex positive lens L12, a negative meniscus lens L13 having a convex surface directed toward the object side, and a biconvex positive lens L14. Here, the negative meniscus lens L13 and the biconvex positive lens L14 are cemented.

  The first sub lens group includes a biconvex positive lens L12. The second sub lens group is composed of a negative meniscus lens L13 and a biconvex positive lens L14.

  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 image side, the fourth lens group G4 moves to the object side, The fifth lens group G5 moves to the object side and then 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 third lens group G3 moves along the optical axis, and at the time of camera shake correction, the biconvex positive lens L12 moves in a direction perpendicular to the optical axis.

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

  The zoom 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 group having a positive refractive power. G3 includes a fourth lens group G4 having a negative refractive power and a fifth lens group G5 having a positive refractive power. The aperture stop S is disposed 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. Yes. Here, the negative meniscus lens L1 and the positive meniscus lens L2 are cemented.

  The second lens group G2 includes a negative meniscus lens L4 having a convex surface directed toward 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 directed toward the object side, and a biconvex positive lens L9. Here, the negative meniscus lens L8 and the biconvex positive lens L9 are cemented.

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

  The fifth lens group G5 includes a biconvex positive lens L11, a negative meniscus lens L12 having a convex surface directed toward the object side, and a biconvex positive lens L13. Here, the negative meniscus lens L12 and the biconvex positive lens L13 are cemented.

  The first sub lens group includes a biconvex positive lens L11. The second sub lens group is composed of a negative meniscus lens L12 and a biconvex positive lens L13.

  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, and the fourth lens group G4 moves to the object side. Moving to the image side, the fifth lens group G5 is fixed. The aperture stop S is fixed.

  During focusing, the fourth lens group G4 moves along the optical axis. During camera shake correction, the biconvex positive lens L11 moves in a direction perpendicular to the optical axis.

  The aspheric surfaces are provided on a total of eight surfaces including both side surfaces of the biconcave negative lens L5, both side surfaces of the biconvex positive lens L7, both side surfaces of the biconcave negative lens L10, and both side surfaces of the biconvex positive lens L11. It has been.

  The zoom optical system of 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 group having a positive refractive power. G3 includes a fourth lens group G4 having a negative refractive power and a fifth lens group G5 having a positive refractive power. The aperture stop S is disposed 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. Yes. Here, the negative meniscus lens L1 and the positive meniscus lens L2 are cemented.

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

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

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

  The fifth lens group G5 includes a biconvex positive lens L11, a negative meniscus lens L12 having a convex surface directed toward the object side, and a biconvex positive lens L13. Here, the negative meniscus lens L12 and the biconvex positive lens L13 are cemented.

  The first sub lens group includes a biconvex positive lens L11. The second sub lens group is composed of a negative meniscus lens L12 and a biconvex positive lens L13.

  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, and the fourth lens group G4 moves to the object side. Moving to the image side, the fifth lens group G5 is fixed. The aperture stop S is fixed.

  During focusing, the fourth lens group G4 moves along the optical axis. During camera shake correction, the biconvex positive lens L11 moves in a direction perpendicular to the optical axis.

  The aspheric surfaces are provided on a total of eight surfaces including both side surfaces of the biconcave negative lens L5, both side surfaces of the positive meniscus lens L7, both side surfaces of the biconcave negative lens L10, and both side surfaces of the biconvex positive lens L11. ing.

  The zoom optical system of Example 7 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 group having a positive refractive power. G3 includes a fourth lens group G4 having a negative refractive power and a fifth lens group G5 having a positive refractive power. The aperture stop S is disposed 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 cemented.

  The second lens group G2 includes a negative meniscus lens L5 having a convex surface directed toward 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 directed toward the object side, and a biconvex positive lens L10. Here, the negative meniscus lens L9 and the biconvex positive lens L10 are cemented.

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

  The fifth lens group G5 includes a biconvex positive lens L12, a biconcave negative lens L13, and a biconvex positive lens L14. Here, the biconcave negative lens L13 and the biconvex positive lens L14 are cemented.

  The first sub lens group includes a biconvex positive lens L12. The second sub lens group includes a biconcave negative lens L13 and a biconvex positive lens L14.

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

  During focusing, the fourth lens group G4 moves along the optical axis. During camera shake correction, the biconvex positive lens L12 moves in a direction perpendicular to the optical axis.

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

  The zoom optical system of Example 8 includes, in order from the object side, a first lens group G1 having a negative refractive power, a second lens group G2 having a positive refractive power, and a third lens group having a negative refractive power. G3 includes a fourth lens group G4 having a positive refractive power and a fifth lens group G5 having a positive refractive power. The aperture stop S is disposed 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 negative meniscus lens L2 having a convex surface facing the object side, a negative meniscus lens L3 having a convex surface facing the object side, and a biconcave negative lens. L4 and a positive meniscus lens L5 having a convex surface facing the object side.

  The second lens group G2 includes a negative meniscus lens L6 having a convex surface directed toward the object side, and a biconvex positive lens L7. Here, the negative meniscus lens L6 and the biconvex positive lens L7 are cemented.

  The third lens group G3 includes a biconvex positive lens L8, a biconcave negative lens L9, a biconvex positive lens L10, and a biconcave negative lens L11.

  The fourth lens group G4 includes a positive meniscus lens L12 having a convex surface directed toward the object side, a negative meniscus lens L13 having a convex surface directed toward the object side, and a biconvex positive lens L14. Here, the negative meniscus lens L13 and the biconvex positive lens L14 are cemented.

  The fifth lens group G5 includes a biconvex positive lens L15, a biconcave negative lens L16, a biconvex positive lens L17, and a biconcave negative lens L18. Here, the biconcave negative lens L16 and the biconvex positive lens L17 are cemented.

  The first sub lens group includes a biconvex positive lens L15. The second sub lens group includes a biconcave negative lens L16, a biconvex positive lens L17, and a biconcave negative lens L18.

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

  During focusing, the second lens group G2 moves along the optical axis. During camera shake correction, the biconvex positive lens L15 moves in a direction perpendicular to the optical axis.

  The aspheric surfaces are provided on a total of six surfaces including both side surfaces of the negative meniscus lens L2, both side surfaces of the positive meniscus lens L12, the object side surface of the biconvex positive lens L15, and the image side surface of the biconcave negative lens L18. Yes.

  Table 2 shows the result of dividing the lens group according to two criteria. The lens group can be divided according to whether or not the distance between adjacent lenses changes. The distance between adjacent lenses changes when zooming or focusing. The grouping of lens groups is different between the case where the lens group is divided based on the change in the distance at the time of zooming and the case where the lens group is divided based on the change in the distance at the time of focusing.

For example, in the second embodiment, when classification is performed based on the interval change at the time of zooming, it is as follows.
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 classified based on the interval change 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

  As described above, the number of lens groups and the number of lenses included in one lens group are divided according to the interval change at the time of zooming and according to the interval change at the time of focusing. Is different.

Assuming that a group of lenses having the smallest number of lenses is a single lens group, the following is the case when the change in the interval at the time of zooming and the change in the interval at the time of focusing are used as a reference.
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, L12, L13

In Table 2, “Language 1” is the case where the lens group is divided by the change in the interval only during zooming, and “Language 2” is the case where the lens group is divided by the change in the interval during zooming and the interval change at the time of focusing. It is said.

  Below, the numerical data of each said Example are shown. In the surface data, r is the radius of curvature of each lens surface, d is the distance between the lens surfaces, nd is the refractive index of the d-line of each lens, νd is the Abbe number of each lens, and * is an aspherical surface.

  In the zoom data, f is the focal length of the zoom optical system, FNO. Is the F number, ω is the half field angle, 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 back focus to the distance from the most object side lens surface to the most image side lens surface. WE is a wide angle end, ST is an intermediate focal length state, and TE is a telephoto end.

  In each group focal length, f1, f2,... Are focal lengths of the lens groups.

The aspherical shape is expressed by the following equation when the optical axis direction is z, the direction orthogonal to the optical axis is y, the cone coefficient is k, and the aspherical coefficients are 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, “e−n” (n is an integer) indicates “10 ⁻ⁿ ”. The symbols of these specification values are common to the numerical data of the examples described later.

Numerical example 1
Unit mm

Surface data surface number rd nd νd
Object ∞ ∞
1 34.469 2.500 1.72916 54.68
2 22.000 6.582
3 * 14.379 2.800 1.49700 81.54
4 * 6.982 6.318
5 18.956 1.500 1.88300 40.76
6 12.192 9.033
7 -57.928 1.150 1.49700 81.54
8 20.683 0.100
9 18.969 3.398 1.90366 31.32
10 47.795 Variable
11 49.077 0.700 1.90366 31.32
12 15.623 3.721 1.76200 40.10
13 -50.213 Variable
14 (Aperture) ∞ 3.033
15 -268.899 3.776 1.49700 81.54
16 -17.125 0.100
17 -17.544 0.700 1.90366 31.32
18 121.455 0.260
19 26.173 3.386 1.80810 22.76
20 -40.802 0.306
21 -34.402 0.700 1.88300 40.76
22 40.587 0.500
23 * 19.315 2.754 1.49700 81.54
24 * -106.534 0.100
25 34.261 0.700 1.88300 40.76
26 12.578 5.939 1.49700 81.54
27 -18.203 Variable
28 * 33.750 4.000 1.49700 81.54
29 -38.814 1.500
30 -50.000 0.700 1.69680 55.53
31 29.032 7.000 1.49700 81.54
32 -18.880 0.100
33 37.523 1.200 1.69350 53.18
34 * 15.442
Image plane ∞

Aspheric data 3rd surface
k = -5.1452
A4 = -1.9119e-005, A6 = 1.7142e-007, A8 = -5.4830e-010,
A10 = 9.1544e-013, A12 = -6.5441e-016, A14 = 0.0000e + 000
4th page
k = -1.5491
A4 = 1.7766e-005, A6 = 6.3967e-007, A8 = -4.2627e-009,
A10 = 1.7518e-011, A12 = -4.1823e-014, A14 = 0.0000e + 000
23rd page
k = 0.0000
A4 = 4.1558e-005, A6 = 1.7862e-007, A8 = -2.8046e-009,
A10 = 7.1475e-011, A12 = 0.0000e + 000, A14 = 0.0000e + 000
24th page
k = 0.0000
A4 = 8.5865e-005, A6 = 3.8320e-007, A8 = -6.5118e-009,
A10 = 9.7933e-011, A12 = 0.0000e + 000, A14 = 0.0000e + 000
28th page
k = 0.0000
A4 = -4.2991e-005, A6 = -1.9973e-007, A8 = 7.5589e-010,
A10 = -2.0666e-012, A12 = 0.0000e + 000, A14 = 0.0000e + 000
34th page
k = 0.0000
A4 = 1.5891e-005, A6 = -1.9482e-007, A8 = 5.3162e-011,
A10 = -1.1083e-012, A12 = -3.1247e-014, A14 = 0.0000e + 000

Zoom data
WE ST TE
f 7.300 9.900 14.031
FNO. 1.967 2.382 2.986
2ω 127.4 105.0 80.8
IH 11.85 11.85 11.85
LTL 113.582 112.346 117.513
BF 15.430 15.430 15.430

d10 15.370 7.338 1.240
d13 7.724 5.520 3.352
d27 0.500 9.500 22.934

Each group focal length
f1 = -11.5429 f2 = 41.3593 f3 = 37.8827 f4 = 106.32

Numerical example 2
Unit mm

Surface data surface number rd nd νd
Object ∞ ∞
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
Image plane ∞

Aspheric 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
13th page
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
14th page
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
21st page
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. 1.731 2.334 3.694
2ω 88.0 30.9 7.4
IH 3.86 3.86 3.86
LTL 135.267 121.686 131.638
BF 5.868 5.868 5.868

d5 0.700 19.944 37.993
d11 42.422 9.597 1.500
d12 21.682 15.217 1.201
d17 1.809 8.274 22.290

Each group focal length
f1 = 69.5426 f2 = -10.6613 f3 = 21.0955 f4 = -16.7221
f5 = 15.85838

Numerical Example 3
Unit mm

Surface data surface number rd nd νd
Object ∞ ∞
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 ∞
Image plane ∞

Aspheric 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
13th page
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
14th page
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 135.4113 135.4113 135.4113
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 = -10.6613 f3 = 21.0955 f4 = -16.7221
f5 = 15.5369

Numerical Example 4
Unit mm

Surface data surface number rd nd νd
Object ∞ ∞
1 92.120 1.600 1.92119 23.96
2 32.500 6.800 1.51633 64.14
3 433.690 0.250
4 37.024 4.600 1.91082 35.25
5 159.340 Variable
6 800.000 0.950 1.78800 47.37
7 11.344 5.429
8 * 179.882 0.800 1.85135 40.10
9 * 15.233 5.797
10 42.969 2.700 1.92286 20.88
11 -104.967 Variable
12 -19.693 0.600 1.49700 81.54
13 -50.402 Variable
14 (Aperture) ∞ Variable
15 * 20.587 4.304 1.80610 40.88
16 * -65.944 4.329
17 35.216 0.650 1.85478 24.80
18 10.461 5.150 1.49700 81.54
19 -39.681 Variable
20 * -21.773 0.700 1.58313 59.38
21 * 17.472 Variable
22 * 17.764 3.800 1.58313 59.38
23 * -50.000 3.800
24 16.092 0.600 2.00100 29.13
25 8.400 6.464 1.55332 71.68
26 -24.899
Image plane ∞

Aspheric data 8th surface
k = 0.0000
A4 = 1.9204e-004, A6 = -4.6001e-006, A8 = 5.9027e-008,
A10 = -4.6276e-010, A12 = 1.6492e-012, A14 = 0.0000e + 000
9th page
k = 0.0000
A4 = 9.2635e-005, A6 = -5.0300e-006, A8 = 5.7997e-008,
A10 = -4.2610e-010, A12 = 1.4426e-012, A14 = 0.0000e + 000
15th page
k = 0.0000
A4 = -3.3191e-006, A6 = -2.7346e-007, A8 = 9.1363e-009,
A10 = -1.5390e-010, A12 = 9.5150e-013, A14 = 0.0000e + 000
16th page
k = 0.0000
A4 = 2.7388e-005, A6 = -3.7164e-007, A8 = 1.1596e-008,
A10 = -1.9852e-010, A12 = 1.2889e-012, A14 = 0.0000e + 000
20th page
k = 0.0000
A4 = 1.4804e-004, A6 = -6.9716e-006, A8 = 2.5556e-007,
A10 = -5.1495e-009, A12 = 5.3645e-011, A14 = 0.0000e + 000
21st page
k = 0.0000
A4 = 9.5164e-005, A6 = -9.0906e-006, A8 = 3.6881e-007,
A10 = -8.4439e-009, A12 = 9.3371e-011, A14 = 0.0000e + 000
22nd page
k = 0.0000
A4 = 4.7318e-005, A6 = -1.5859e-006, A8 = 2.8805e-008,
A10 = -4.3652e-010, A12 = 1.2135e-013, A14 = 0.0000e + 000
23rd page
k = 0.0000
A4 = 1.1433e-004, A6 = -2.1168e-006, A8 = 4.6215e-008,
A10 = -8.8917e-010, A12 = 3.9636e-012, A14 = 0.0000e + 000

Zoom data
WE ST TE
f 3.920 13.901 55.482
FNO. 1.632 2.500 3.750
2ω 88.3 28.1 7.3
IH 3.60 3.60 3.60
LTL 137.265 137.265 137.265
BF 6.581 6.581 6.581

d5 0.700 18.594 34.123
d11 12.834 4.127 3.688
d13 25.577 16.390 1.300
d14 20.450 3.847 1.196
d19 1.800 8.403 24.049
d21 10.000 20.000 7.005

Each group focal length
f1 = 63.7451 f2 = -13.8805 f3 = -65.4593 f4 = 19.7499
f5 = -16.5148 f6 = 15.8345

Numerical Example 5
Unit mm

Surface data surface number rd nd νd
Object ∞ ∞
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 ∞
Image plane ∞

Aspheric 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
13th page
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
14th page
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 + 0000
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
21st page
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 135.267 135.267 135.267
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 = -10.6613 f3 = 21.0955 f4 = -16.7221
f5 = 15.8584

Numerical Example 6
Unit mm

Surface data surface number rd nd νd
Object ∞ ∞
1 172.259 1.400 1.80000 29.84
2 34.197 8.700 1.49700 81.54
3 1460.498 0.142
4 44.219 5.350 1.88300 40.76
5 512.943 Variable
6 2423.461 0.800 1.75500 52.32
7 10.943 6.466
8 * -60.609 0.800 1.85135 40.10
9 * 15.318 3.626
10 46.981 2.850 2.00069 25.46
11 -60.777 Variable
12 (Aperture) ∞ Variable
13 * 17.473 4.255 1.80610 40.88
14 * 5183.259 4.168
15 24.073 1.156 1.85478 24.80
16 9.050 5.689 1.49700 81.54
17 -38.695 variable
18 * -39.794 1.380 1.51633 64.14
19 * 10.215 Variable
20 * 10.888 5.000 1.59201 67.02
21 * -34.693 0.700
22 84.518 0.679 1.91082 35.25
23 8.600 5.937 1.59282 68.63
24 -17.000 1.223
25 ∞ 0.300 1.51633 64.14
26 ∞
Image plane ∞

Aspheric data 8th surface
k = 0.0000
A4 = 2.4982e-004, A6 = -6.3097e-006, A8 = 7.4826e-008,
A10 = -4.8887e-010, A12 = 1.3090e-012, A14 = 0.0000e + 000
9th page
k = 0.0000
A4 = 1.1296e-004, A6 = -6.5158e-006, A8 = 7.8796e-008,
A10 = -5.1308e-010, A12 = 1.3875e-012, A14 = 0.0000e + 000
13th page
k = 0.0000
A4 = -1.3869e-005, A6 = 3.6314e-008, A8 = -1.0447e-009,
A10 = 1.2984e-011, A12 = -1.9446e-013, A14 = 0.0000e + 000
14th page
k = 0.0000
A4 = 1.5375e-005, A6 = -1.8471e-008, A8 = 7.7633e-010,
A10 = -1.9570e-011, A12 = -4.4054e-014, A14 = 0.0000e + 000
18th page
k = 0.0000
A4 = 3.8084e-004, A6 = -1.1061e-005, A8 = 1.5509e-007,
A10 = -5.1645e-010, A12 = -8.3679e-012, A14 = 0.0000e + 000
19th page
k = 0.0000
A4 = 3.7263e-004, A6 = -1.0803e-005, A8 = 4.6473e-008,
A10 = 2.7164e-009, A12 = -4.6246e-011, A14 = 0.0000e + 000
20th page
k = 0.0000
A4 = -8.0337e-006, A6 = -9.6749e-007, A8 = -3.4950e-008,
A10 = 1.1473e-009, A12 = -1.6740e-011, A14 = 0.0000e + 000
21st page
k = 0.0000
A4 = 2.2738e-004, A6 = -4.8854e-006, A8 = 8.1344e-008,
A10 = -1.0966e-009, A12 = 8.6599e-013, A14 = 0.0000e + 000

Zoom data
WE ST TE
f 3.880 13.900 54.911
FNO. 1.535 2.448 3.615
2ω 94.2 30.7 8.0
IH 3.90 3.90 3.90
LTL 133.266 133.266 133.266
BF 3.500 3.500 3.500

d5 0.652 21.730 38.666
d11 39.284 18.206 1.270
d12 24.209 8.359 1.200
d17 1.800 6.158 18.490
d19 3.300 14.792 9.619

Each group focal length
f1 = 70.5085 f2 = -11.245 f3 = 19.5499 f4 = -15.5968
f5 = 14.4976

Numerical Example 7
Unit mm

Surface data surface number rd nd νd
Object ∞ ∞
1 66.004 1.400 2.00330 28.27
2 38.845 6.600 1.43700 95.10
3 -5121.326 0.150
4 45.472 3.850 1.49700 81.61
5 390.188 0.150
6 28.589 4.112 1.59282 68.63
7 86.592 Variable
8 * 250.431 0.700 1.88202 37.22
9 * 5.800 3.217
10 -15.216 0.700 1.88300 40.76
11 25.038 0.158
12 15.612 2.000 1.95906 17.47
13 -77.613 Variable
14 (Aperture) ∞ 1.600
15 * 14.305 6.618 1.49700 81.54
16 * -18.618 0.100
17 55.444 0.800 1.95906 17.47
18 26.621 5.500 1.59282 68.63
19 -19.566 Variable
20 * -21.828 0.600 1.61881 63.85
21 * 11.866 Variable
22 * 13.609 2.600 1.69350 53.18
23 * -23.632 1.400
24 -50.000 0.500 1.67270 32.10
25 5.832 4.000 1.61800 63.40
26 -19.455
Image plane ∞

Aspheric data 8th surface
k = 0.0000
A4 = 1.1657e-004, A6 = -4.7771e-006, A8 = 1.0266e-007,
A10 = -1.2292e-009, A12 = 6.8533e-012, A14 = 0.0000e + 000
9th page
k = 0.0000
A4 = 2.8399e-005, A6 = -5.0316e-006, A8 = 7.6629e-008,
A10 = -5.6198e-009, A12 = 7.3385e-015, A14 = 0.0000e + 000
15th page
k = 0.0000
A4 = -6.7271e-005, A6 = -5.6952e-008, A8 = 4.3217e-009,
A10 = 0.0000e + 000, A12 = 0.0000e + 000, A14 = 0.0000e + 000
16th page
k = 0.0000
A4 = 1.5796e-004, A6 = -3.0143e-007, A8 = 9.1071e-009,
A10 = 0.0000e + 000, A12 = 0.0000e + 000, A14 = 0.0000e + 000
20th page
k = 0.0000
A4 = 4.3078e-004, A6 = 8.3968e-008, A8 = 5.8477e-008,
A10 = -2.0285e-009, A12 = 1.1271e-011, A14 = -9.0058e-016
21st page
k = 0.0000
A4 = 2.5317e-004, A6 = 7.9304e-006, A8 = 1.0323e-007,
A10 = -7.7729e-011, A12 = 1.4809e-012, A14 = -9.2727e-014
22nd page
k = 0.0000
A4 = -2.1886e-004, A6 = -2.7224e-006, A8 = -4.4772e-008,
A10 = 0.0000e + 000, A12 = 0.0000e + 000, A14 = 0.0000e + 000
23rd page
k = 0.0000
A4 = -5.7837e-005, A6 = -5.0381e-006, A8 = 1.2328e-008,
A10 = 0.0000e + 000, A12 = 0.0000e + 000, A14 = 0.0000e + 000

Zoom data
WE ST TE
f 4.400 24.502 110.303
FNO. 1.284 2.708 3.912
2ω 74.1 14.5 3.2
IH 3.20 3.20 3.20
LTL 91.334 91.334 91.334
BF 2.794 2.794 2.794

d7 0.600 20.511 28.740
d13 28.361 8.450 0.221
d19 3.500 9.017 2.821
d21 9.324 3.807 10.003

Each group focal length
f1 = 41.3141 f2 = -5.95179 f3 = 12.667 f4 = -12.3386
f5 = 12.4793

Numerical Example 8
Unit mm

Surface data surface number rd nd νd
Object ∞ ∞
1 32.958 2.500 1.72916 54.68
2 22.000 6.718
3 * 14.650 2.800 1.49700 81.54
4 * 6.982 6.128
5 18.885 1.500 1.88300 40.76
6 12.192 9.331
7 -37.493 1.150 1.49700 81.54
8 23.368 0.100
9 20.920 3.295 1.90366 31.32
10 65.843 Variable
11 45.610 0.700 1.90366 31.32
12 14.567 3.710 1.76200 40.10
13 -61.117 Variable
14 (Aperture) ∞ 3.233
15 558.614 2.201 1.49700 81.54
16 -18.807 0.398
17 -19.200 0.700 1.90366 31.32
18 676.224 0.422
19 31.028 4.500 1.80810 22.76
20 -51.532 0.280
21 -43.996 0.700 1.88300 40.76
22 43.492 Variable
23 * 17.431 3.576 1.49700 81.54
24 * 123.888 0.100
25 32.396 0.700 1.88300 40.76
26 12.894 5.405 1.49700 81.54
27 -20.350 Variable
28 * 25.139 4.000 1.49700 81.54
29 -60.137 1.500
30 -55.825 0.700 1.73400 51.47
31 40.354 7.000 1.49700 81.54
32 -17.122 0.100
33 -127.773 1.200 1.69350 53.18
34 * 29.469
Image plane ∞

Aspheric data 3rd surface
k = -5.1578
A4 = -2.6367e-005, A6 = 1.9350e-007, A8 = -5.5344e-010,
A10 = 8.6354e-013, A12 = -5.9596e-016, A14 = 0.0000e + 000
4th page
k = -1.4638
A4 = -6.3458e-006, A6 = 6.5895e-007, A8 = -4.0609e-009,
A10 = 1.8497e-011, A12 = -4.6613e-014, A14 = 0.0000e + 000
23rd page
k = 0.0000
A4 = 5.3550e-005, A6 = 2.5268e-007, A8 = -1.1773e-009,
A10 = 6.9280e-011, A12 = 0.0000e + 000, A14 = 0.0000e + 000
24th page
k = 0.0000
A4 = 9.7341e-005, A6 = 5.2429e-007, A8 = -6.3742e-009,
A10 = 1.3623e-010, A12 = 0.0000e + 000, A14 = 0.0000e + 000
28th page
k = 0.0000
A4 = -1.8653e-005, A6 = -1.7106e-007, A8 = -1.7490e-010,
A10 = -2.7884e-012, A12 = 0.0000e + 000, A14 = 0.0000e + 000
34th page
k = 0.0000
A4 = 4.9646e-005, A6 = 2.0461e-007, A8 = -4.7353e-009,
A10 = 6.4260e-011, A12 = -3.6929e-013, A14 = 0.0000e + 000

Zoom data
WE ST TE
f 7.299 9.899 14.026
FNO. 2.880 2.880 2.880
2ω 119.9 98.8 75.6
IH 10.80 10.80 10.80
LTL 113.574 113.212 118.104
BF 14.367 14.367 14.367

d10 14.271 7.305 1.246
d13 9.057 6.973 3.474
d22 0.733 0.171 0.739
d27 0.500 9.750 23.631

Each group focal length
f1 = -11.4848 f2 = 44.9051 f3 = -53.7943 f4 = 23.2175
f5 = 90.307

Next, the values of the conditional expressions in each example are listed below. The value described in the following (2) corresponds to the value of the conditional expression (2-1) and the value of the conditional expression (2-2). The value described in the following (8) corresponds to the value of the conditional expression (8-1). The value described in the following (17) corresponds to the value of the conditional expression (17-1). The value described in the following (25) corresponds to the value of the conditional expression (25-1). A hyphen (-) indicates that a value cannot be calculated.

Example 1 Example 2 Example 3 Example 4
(1) fGBUN1 / fGPM 0.977 1.043 1.061 1.162
(2) νdGPMP1 81.54 81.54 81.54 81.54
(3) DGBUN12a / fGBUN1 0.041 0.173 0.156 0.166
(4) | (MGGBUN1back) ×
(MGGBUN1-1) | 0.696 0.646 0.625 0.640
(5) SFGBUN1 -0.070 -0.970 -0.970 -0.476
(6) fGPM / fw 5.190 5.382 5.468 5.038
(7) fGBUN1 / fw 5.069 5.612 5.803 5.855
(8) | LTLmax / fGN1 | 10.181 12.688 12.701 9.889
(9) | fGN1 / fGPM | 0.305 0.505 0.505 0.703
(10) | fGN1 / fw | 1.581 2.720 2.763 3.541
(11) fGB / fw 14.565 4.046 4.027 4.039
(12) fGBUN1 / IHw35 7.239 8.015 8.287 8.362
(13) | fGN1 / IHw35 | 2.258 3.884 3.946 5.057
(14) DGBUN12a / fw 0.205 0.969 0.907 0.969
(15) νdGBUN1P 81.54 59.38 59.38 59.38
(16) νdGBUN2N 53.18 29.13 29.13 29.13
(17) ΩHw / 2 56.256 40.118 42.887 39.998
(18) fGP1 / fGPM − 3.297 3.297 3.228
(19) | fGPM / fGNB | − 1.262 1.262 1.196
(20) fGN1 / fGNB − 0.638 0.638 0.840
(21) ΔGPMM / LTLw 0.198 0.151 0.178 0.140
(22) ft / fw 1.922 13.742 14.148 14.153
(23) FNOw 2.986 1.731 1.616 1.632
(24) FNOt 1.967 3.694 3.743 3.750
(25) ft / fw + 13.38
× tan (ΩHw / 2) -21.0 0.95 4.02 5.58 4.38
(26) ΣGP1 / LTLw − 0.099 0.099 0.097
(27) fw × FNOw / fGN1 -1.244 -0.636 -0.585 -0.461
(28) SPGN1Ln1 4.529 − − −
(29) DTw -16.2307 -5.77414 -5.12255 -5.37673
(30) Rimg 11.85 3.57 3.9 3.6

Example 5 Example 6 Example 7 Example 8
(1) fGBUN1 / fGPM 1.043 0.746 1.01 1.561
(2) νdGPMP1 81.54 81.54 81.54 81.54
(3) DGBUN12a / fGBUN1 0.173 0.048 0.109 0.041
(4) | (MGGBUN1back) ×
(MGGBUN1-1) | 0.646 0.802 0.609 0.692
(5) SFGBUN1 -0.970 -0.522 -0.269 -0.410
(6) fGPM / fw 5.382 5.039 2.879 3.181
(7) fGBUN1 / fw 5.613 3.761 2.913 4.964
(8) | LTLmax / fGN1 | 12.688 11.860 15.346 10.284
(9) | fGN1 / fGPM | 0.505 0.575 0.470 0.495
(10) | fGN1 / fw | 2.720 2.898 1.353 1.573
(11) fGB / fw 4.046 3.736 2.836 12.372
(12) fGBUN1 / IHw35 8.016 5.372 4.161 7.090
(13) | fGN1 / IHw35 | 3.884 4.139 1.932 2.247
(14) DGBUN12a / fw 0.969 0.180 0.318 0.206
(15) νdGBUN1P 59.38 67.02 53.18 81.54
(16) νdGBUN2N 29.13 35.25 32.1 51.47
(17) ΩHw / 2 43.045 43.180 33.343 55.680
(18) fGP1 / fGPM 3.297 3.607 3.262 −
(19) | fGPM / fGNB | 1.262 1.253 1.027 −
(20) fGN1 / fGNB 0.638 0.721 0.482 −
(21) ΔGPMM / LTLw 0.178 0.173 − 0.204
(22) ft / fw 14.148 14.152 25.068 1.922
(23) FNOw 1.642 1.535 1.284 2.880
(24) FNOt 3.803 3.615 3.912 2.880
(25) ft / fw + 13.38
× tan (ΩHw / 2) -21.0 5.64 5.71 12.87 0.52
(26) ΣGP1 / LTLw 0.099 0.117 0.178 −
(27) fw × FNOw / fGN1 -0.604 -0.530 -0.949 -1.830
(28) SPGN1Ln1 − − − 5.015
(29) DTw -4.74879 -6.62018 -3.63712 -14.3949
(30) Rimg 4 3.9 3.2 10.8

  FIG. 29 is a cross-sectional view of a single lens mirrorless camera as an electronic imaging apparatus. In FIG. 29, the photographing optical system 2 can be arranged in the lens barrel of the single lens mirrorless camera 1. The mount 3 enables the photographing optical system 2 to be attached to and detached 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. In addition, an imaging element surface 4 and a back monitor 5 can be disposed on the body of the single-lens mirrorless camera 1. Note that an image sensor, a small CCD, a CMOS, or the like can be used as the image sensor.

  As the photographing optical system 2 of the single-lens mirrorless camera 1, for example, the zoom optical system shown in the first to eighth embodiments can be used.

  30 and 31 are conceptual diagrams of the configuration of the imaging apparatus. 30 is a front perspective view of a digital camera 40 as an imaging device, and FIG. 31 is a rear perspective view of the same. The zoom optical system of this embodiment can be used for the photographing optical system 41 of the digital camera 40.

  The digital camera 40 of this embodiment can include a photographing optical system 41 positioned on the 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, photographing can be performed through the photographing optical system 41, for example, the zoom optical system of the first embodiment in conjunction therewith. The object image formed by the photographing optical system 41 can be formed on an image sensor (photoelectric conversion surface) provided in the vicinity of the image forming surface. The object image received by the image sensor can be displayed as an electronic image on the liquid crystal display monitor 47 provided on the back of the camera by the processor. The taken electronic image can be recorded in a memory.

  FIG. 32 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 constituted by, for example, the CDS / ADC 24, the temporary storage memory 17, the processor 18, and the like. The memory can be composed of a storage 19 or the like.

  As shown in FIG. 32, the digital camera 40 is connected to the input device 12, the control unit 13 connected to the input device 12, and the control signal output port of the control unit 13 via buses 14 and 15. The imaging drive circuit 16 and the temporary storage memory 17, the processor 18, the storage 19, the display 20, and the setting information storage memory 21 may be provided.

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

  The input device 12 may include various input buttons and switches. Event information input from outside (camera user) via these can be notified to the control unit 13. The control unit 13 is a central processing unit composed of, 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 and can convert the light quantity of each pixel of the object image formed via the imaging optical system 41 into an electrical signal and output it to the CDS / ADC 24.

  The CDS / ADC 24 amplifies the electric signal input from the image sensor 49, performs analog / digital conversion, and performs raw video data (Bayer data, hereinafter referred to as RAW data) that is simply subjected to the amplification and digital conversion. Is a circuit that can output to the temporary storage memory 17.

  The temporary storage memory 17 may be a buffer made of, for example, SDRAM or the like, 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. It is a circuit that can be performed electrically.

  The storage 19 is detachably mounted with a card-type or stick-type recording medium made of, for example, a flash memory or the like, and RAW data transferred from the temporary storage memory 17 or image processing is performed on these flash memories by the processor 18. Image data can be recorded and retained.

  The display 20 includes a liquid crystal display monitor 47 and the like, and can display captured RAW data, image data, an operation menu, and the like. The setting information storage memory 21 may include a ROM unit that stores various image quality parameters 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. 21 shows the configuration of the video conference system. The video conference system 100 can include a plurality of video conference apparatuses 110, 120, and 130. Each of the video conference apparatuses 110, 120, and 130 can be connected to a network, for example, a wide area network (WAN) 140.

  The video conference apparatus 110 can include a main body 111, a camera 112, and a display 113. Similarly, the video conference apparatus 120 and the video conference apparatus 130 may include similar units. The camera 112 can include, for example, the variable magnification optical system and the image sensor of the first embodiment. Through the camera 112, a conference participant or conference material can be photographed.

  The video conference apparatuses 110, 120, and 130 can be arranged at bases (remote places) that are separated from each other. Therefore, the video of each of the conference participants 119, 129, and 139 can be transmitted via the wide area network (WAN) 140 to the video conference device used by the other conference participants. As a result, the video image 129 ′ of the conference participant 129 and the video image 139 ′ of the conference participant 139 can be displayed on the display 113. In addition, audio can be transmitted together with video transmission. 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 of the conference participants other than themselves and the content of the remarks even if the bases of the conferences are remote locations. However, the conference can proceed. Note that the video conference apparatus used at each site is not necessarily the same apparatus.

  The present invention can take various modifications without departing from the spirit of the present invention. Further, the number of shapes shown in the above embodiments is not necessarily limited. Moreover, in each said Example, a cover glass does not necessarily need to arrange | position. In addition, a lens that is not illustrated in each of the above embodiments and has substantially no refractive power may be disposed in each lens group or outside each lens group.

  As described above, the present invention can ensure a wide angle of view at the wide-angle end and a small F number, and is suitable for a zoom optical system in which various aberrations are well corrected and an image pickup apparatus including the same. Yes.

G1 1st lens group G2 2nd lens group G3 3rd lens group G4 4th lens group G5 5th lens group G6 6th lens group S Aperture stop I Image surface 1 Single-lens mirrorless camera 2 Shooting optical system 3 Mount of lens barrel 4 Image sensor surface 5 Back monitor 12 Input device 13 Control unit 14, 15 Bus 16 Imaging drive circuit 17 Temporary memory 18 Processor 19 Storage 20 Display 21 Setting information memory 22 Bus 24 CDS / ADC
DESCRIPTION OF SYMBOLS 40 Digital camera 41 Imaging optical system 42 Optical path for imaging 45 Shutter button 47 Liquid crystal display monitor 49 Imaging 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 participant 119 ', 129', 139 'Video of conference participant 140 Wide Area Network (WAN)

Claims (69)

Having a plurality of lens groups and an aperture stop,
The plurality of lens groups includes two or more lens groups having a positive refractive power and one or more lens groups having a negative refractive power,
The two or more lens groups having a positive refractive power include a positive lens group having a positive refractive power and an image side positive lens group,
The one or more lens groups having negative refractive power include an object-side negative lens group,
The image-side positive lens group does not move along the optical axis at any time of zooming or focusing,
In the plurality of lens groups, the distance between the adjacent lens groups changes at the time of zooming, focusing, or zooming and focusing, respectively.
The positive lens group has the largest refractive power among the two or more lens groups having the positive refractive power excluding the image side positive lens group, and has a predetermined condition that satisfies the following conditional expression (2): Have a positive lens,
The image side positive lens group is located closest to the image side among the two or more lens groups having positive refractive power,
When the plurality of lens groups have two or more lens groups having negative refractive power, the object-side negative lens group is closest to the object side among the one or more lens groups having negative refractive power. Position to,
The object side negative lens group moves so that the distance between the object side negative lens group and the positive lens group at the time of focusing on an object at infinity is narrower at the telephoto end than at the wide angle end,
The aperture stop is positioned between a lens surface located closest to the image side in the object side negative lens group and a lens surface located closest to the image side in the positive lens group, or the positive lens group Next to the lens surface located closest to the image side in
The image side positive lens group includes a first sub lens group having a positive refractive power, and a second sub lens group including a positive lens and a negative lens.
A zoom optical system satisfying the following conditional expression (1):
0.1 ≦ fGBUN1 / fGPM ≦ 2.1 (1)
60.8 ≦ νdGPMP1 ≦ 100.0 (2)
here,
fGBUN1 is the focal length of the first sub lens group,
fGPM is the focal length of the positive lens group,
νdGPMP1 is the Abbe number of the predetermined positive lens,
The predetermined positive lens is a positive lens having a maximum Abbe number among the positive lenses in the positive lens group,
The lens component is a single lens or a cemented lens,
It is. Having a plurality of lens groups and an aperture stop,
The plurality of lens groups includes two or more lens groups having a positive refractive power and one or more lens groups having a negative refractive power,
The two or more lens groups having a positive refractive power include a positive lens group having a positive refractive power and an image side positive lens group,
The one or more lens groups having negative refractive power include an object-side negative lens group,
The image-side positive lens group does not move along the optical axis at any time of zooming or focusing,
In the plurality of lens groups, the distance between the adjacent lens groups changes at the time of zooming, focusing, or zooming and focusing, respectively.
The positive lens group has the largest refractive power among the two or more lens groups having the positive refractive power excluding the image side positive lens group,
The image side positive lens group is located closest to the image side among the two or more lens groups having positive refractive power,
When the plurality of lens groups have two or more lens groups having negative refractive power, the object-side negative lens group is closest to the object side among the one or more lens groups having negative refractive power. Position to,
The object side negative lens group moves so that the distance between the object side negative lens group and the positive lens group at the time of focusing on an object at infinity is narrower at the telephoto end than at the wide angle end,
The aperture stop is positioned between a lens surface located closest to the image side in the object side negative lens group and a lens surface located closest to the image side in the positive lens group, or the positive lens group Next to the lens surface located closest to the image side in
The image side positive lens group includes a first sub lens group having a positive refractive power, and a second sub lens group including a positive lens and a negative lens.
A zoom optical system satisfying the following conditional expressions (3) and (4):
0.02 ≦ DGBUN12a / fGBUN1 ≦ 4.0 (3)
0.43 ≦ | (MGGBUN1back) × (MGGBUN1-1) | ≦ 5.0 (4)
here,
DGBUN12a is an air gap between the first sub lens group and the second sub lens group,
fGBUN1 is the focal length of the first sub lens group,
MGGBUN1 is a lateral magnification in the first sub lens group,
MGGBUN1back is the lateral magnification in a given optical system,
The predetermined optical system is an optical system composed of all lenses positioned on the image side of the first sub lens group,
The horizontal magnification is the horizontal magnification when focusing on an object at infinity,
The lens component is a single lens or a cemented lens,
It is. Having a plurality of lens groups and an aperture stop,
The plurality of lens groups includes two or more lens groups having a positive refractive power and one or more lens groups having a negative refractive power,
The two or more lens groups having a positive refractive power include a positive lens group having a positive refractive power and an image side positive lens group,
The one or more lens groups having negative refractive power include an object-side negative lens group,
The image-side positive lens group does not move along the optical axis at any time of zooming or focusing,
In the plurality of lens groups, the distance between the adjacent lens groups changes at the time of zooming, focusing, or zooming and focusing, respectively.
The positive lens group has the largest refractive power among the two or more lens groups having the positive refractive power excluding the image side positive lens group, and satisfies the following conditional expression (2-1). Having a predetermined positive lens,
The image side positive lens group is located closest to the image side among the two or more lens groups having positive refractive power,
When the plurality of lens groups have two or more lens groups having negative refractive power, the object-side negative lens group is closest to the object side among the one or more lens groups having negative refractive power. Position to,
The object side negative lens group moves so that the distance between the object side negative lens group and the positive lens group at the time of focusing on an object at infinity is narrower at the telephoto end than at the wide angle end,
The aperture stop is positioned between a lens surface located closest to the image side in the object side negative lens group and a lens surface located closest to the image side in the positive lens group, or the positive lens group Next to the lens surface located closest to the image side in
The image side positive lens group includes a first sub lens group having a positive refractive power, and a second sub lens group including a positive lens and a negative lens.
A zoom optical system satisfying the following conditional expression (5):
64.8 ≦ νdGPMP1 ≦ 100.0 (2-1)
-2.6 ≦ SFGBUN1 ≦ 0.95 (5)
here,
νdGPMP1 is the Abbe number of the predetermined positive lens,
The predetermined positive lens is a positive lens having a maximum Abbe number among the positive lenses in the positive lens group,
SFGBUN1 is represented by the following equation:
SFGBUN1 = (RGBUN1f) + (RGBUN1r) / (RGBUN1f−RGBUN1)
RGBUN1f is the radius of curvature of the lens surface located closest to the object side of the first sub lens group,
RGBUN1r is the radius of curvature of the lens surface located closest to the image side of the first sub lens group. The lens component is a single lens or a cemented lens,
It is. Having a plurality of lens groups and an aperture stop,
The plurality of lens groups includes two or more lens groups having a positive refractive power and one or more lens groups having a negative refractive power,
The two or more lens groups having a positive refractive power include a positive lens group having a positive refractive power and an image side positive lens group,
The one or more lens groups having negative refractive power include an object-side negative lens group,
The image-side positive lens group does not move along the optical axis at any time of zooming or focusing,
In the plurality of lens groups, the distance between the adjacent lens groups changes at the time of zooming, focusing, or zooming and focusing, respectively.
The positive lens group has the largest refractive power among the two or more lens groups having the positive refractive power excluding the image side positive lens group,
The image side positive lens group is located closest to the image side among the two or more lens groups having positive refractive power,
When the plurality of lens groups have two or more lens groups having negative refractive power, the object-side negative lens group is closest to the object side among the one or more lens groups having negative refractive power. Position to,
The object side negative lens group moves so that the distance between the object side negative lens group and the positive lens group at the time of focusing on an object at infinity is narrower at the telephoto end than at the wide angle end,
The aperture stop is positioned between a lens surface located closest to the image side in the object side negative lens group and a lens surface located closest to the image side in the positive lens group, or the positive lens group Next to the lens surface located closest to the image side in
The image side positive lens group includes a first sub lens group having a positive refractive power, and a second sub lens group including a positive lens and a negative lens.
The distance between the image side positive lens group and the lens group located next to the image side positive lens group changes during zooming,
The lens surface located closest to the image side of the first sub lens group is a convex surface on the image side,
A zoom optical system satisfying the following conditional expressions (6), (7), and (8):
2.0 ≦ fGPM / fw ≦ 20.0 (6)
2.3 ≦ fGBUN1 / fw ≦ 9.7 (7)
3.0 ≦ | LTLmax / fGN1 | ≦ 16.3 (8)
here,
fGPM is the focal length of the positive lens group,
fGBUN1 is the focal length of the first sub lens group,
fw is the focal length of the zoom optical system at the wide-angle end,
LTLmax is the maximum length among the total length of the zoom optical system,
fGN1 is the focal length of the object side negative lens unit,
The lens component is a single lens or a cemented lens,
It is.   4. The zoom optical system according to claim 1, wherein a lens surface located closest to the image side of the first sub lens group is a convex surface toward the image side. 5.   4. The zoom optical system according to claim 1, wherein an interval between the image-side positive lens group and a lens group located next to the image-side positive lens group changes during zooming. 5. system. The zoom optical system according to any one of claims 2 to 4, wherein the following conditional expression (1) is satisfied.
0.1 ≦ fGBUN1 / fGPM ≦ 2.1 (1)
here,
fGBUN1 is the focal length of the first sub lens group,
fGPM is the focal length of the positive lens group,
It is. 5. The zoom optical system according to claim 2, wherein the positive lens group includes a predetermined positive lens that satisfies the following conditional expression (2-2).
60 ≦ νdGPMP1 ≦ 100.0 (2-2)
here,
νdGPMP1 is the Abbe number of the predetermined positive lens,
The predetermined positive lens is a positive lens having a maximum Abbe number among the positive lenses in the positive lens group,
It is. The zoom optical system according to claim 1, wherein the following conditional expression (3) is satisfied.
0.02 ≦ DGBUN12a / fGBUN1 ≦ 4.0 (3)
here,
DGBUN12a is an air gap between the first sub lens group and the second sub lens group,
fGBUN1 is the focal length of the first sub lens group,
It is. The zoom optical system according to claim 1, wherein the following conditional expression (4) is satisfied.
0.43 ≦ | (MGGBUN1back) × (MGGBUN1-1) | ≦ 5.0 (4)
here,
MGGBUN1 is a lateral magnification in the first sub lens group,
MGGBUN1back is the lateral magnification in a given optical system,
The predetermined optical system is an optical system composed of all lenses positioned on the image side of the first sub lens group,
The horizontal magnification is the horizontal magnification when focusing on an object at infinity,
It is. The zoom optical system according to claim 1, wherein the following conditional expression (5) is satisfied.
-2.6 ≦ SFGBUN1 ≦ 0.95 (5)
here,
νdGPMP1 is the Abbe number of the predetermined positive lens,
The predetermined positive lens is a positive lens having a maximum Abbe number among the positive lenses in the positive lens group,
SFGBUN1 is represented by the following equation:
SFGBUN1 = (RGBUN1f) + (RGBUN1r) / (RGBUN1f−RGBUN1)
RGBUN1f is the radius of curvature of the lens surface located closest to the object side of the first sub lens group,
RGBUN1r is the radius of curvature of the lens surface located closest to the image side of the first sub lens group. The zoom optical system according to any one of claims 1 to 3, wherein the following conditional expression (6) is satisfied.
2.0 ≦ fGPM / fw ≦ 20.0 (6)
here,
fGPM is the focal length of the positive lens group,
fw is the focal length of the zoom optical system at the wide-angle end,
The lens component is a single lens or a cemented lens,
It is. The zoom optical system according to any one of claims 1 to 3, wherein the following conditional expression (7) is satisfied.
2.3 ≦ fGBUN1 / fw ≦ 9.7 (7)
here,
fGBUN1 is the focal length of the first sub lens group,
fw is the focal length of the zoom optical system at the wide-angle end,
It is. The zoom optical system according to claim 1, wherein the following conditional expression (8-1) is satisfied.
1.0 ≦ | LTLmax / fGN1 | ≦ 19.0 (8-1)
here,
LTLmax is the maximum length among the total length of the zoom optical system,
fGN1 is the focal length of the object side negative lens unit,
It is.   6. The zoom optical system according to claim 4, wherein a lens surface located closest to the object side of the first sub lens group is a convex surface toward the object side.   16. The zoom optical system according to claim 1, wherein the positive lens group moves so as to be positioned closer to the object side at the telephoto end than at the wide-angle end when an object at infinity is in focus. The zoom optical system according to any one of claims 1 to 16, wherein the following conditional expression (9) is satisfied.
0.25 ≦ | fGN1 / fGPM | ≦ 2.0 (9)
here,
fGN1 is the focal length of the object side negative lens unit,
fGPM is the focal length of the positive lens group,
It is. The zoom optical system according to any one of claims 1 to 17, wherein the following conditional expression (10) is satisfied.
1.05 ≦ | fGN1 / fw | ≦ 5.5 (10)
here,
fGN1 is the focal length of the object side negative lens unit,
fw is the focal length of the zoom optical system at the wide-angle end,
It is. The zoom optical system according to any one of claims 1 to 18, wherein the following conditional expression (11) is satisfied.
2.0 ≦ fGB / fw ≦ 23 (11)
here,
fGB is a focal length of the image-side positive lens unit,
fw is the focal length of the zoom optical system at the wide-angle end,
It is. The zoom optical system according to any one of claims 1 to 19, wherein the following conditional expression (12) is satisfied.
3.5 ≦ fGBUN1 / IHw35 ≦ 14.0 (12)
here,
fGBUN1 is the focal length of the first sub lens group,
IHw35 is represented by the following formula:
IHw35 = fw × tan35 °,
fw is the focal length of the zoom optical system at the wide-angle end,
It is. The zoom optical system according to any one of claims 1 to 20, wherein the following conditional expression (13) is satisfied.
1.8 ≦ | fGN1 / IHw35 | ≦ 8.0 (13)
here,
fGN1 is the focal length of the object side negative lens unit,
IHw35 is represented by the following formula:
IHw35 = fw × tan35 °,
fw is the focal length of the zoom optical system at the wide-angle end,
It is. The zoom optical system according to any one of claims 1 to 21, wherein the following conditional expression (14) is satisfied.
0.1 ≦ DGBUN12a / fw ≦ 2.0 (14)
here,
DGBUN12a is an air gap between the first sub lens group and the second sub lens group,
fw is the focal length of the zoom optical system at the wide-angle end,
It is.   The zoom optical system according to any one of claims 1 to 22, wherein the first sub lens group includes a lens component having no air interval. The first sub lens group includes one positive lens,
The zoom optical system according to any one of claims 1 to 23, wherein the following conditional expression (15) is satisfied.
52 ≦ νdGBUN1P ≦ 100.0 (15)
here,
νdGBUN1P is the Abbe number of the positive lens of the first sub lens group,
It is.   The zoom optical system according to any one of claims 1 to 24, wherein the second sub lens group includes a negative lens and a positive lens. The first sub lens group includes one positive lens,
The zoom optical system according to any one of claims 1 to 25, wherein the second sub lens group includes one negative lens and one positive lens.   The zoom optical system according to any one of claims 1 to 26, wherein the second sub lens group includes a negative lens, a positive lens, and a negative lens disposed closest to the image side. .   28. The zoom optical system according to claim 25, wherein the positive lens and the negative lens of the second sub lens group are cemented.   The zoom optical system according to any one of claims 1 to 28, wherein the second sub lens group is fixed at the time of zooming. 25. The zoom optical system according to claim 1, wherein the second sub lens group includes a negative lens that satisfies the following conditional expression (16).
18.5 ≦ νdGBUN2N ≦ 55.0 (16)
here,
νdGBUN2N is the Abbe number of the negative lens of the second sub lens group,
It is.   The zoom optical system according to any one of claims 1 to 30, wherein the aperture stop is disposed on the object side of the positive lens group. A moving lens group is disposed on the object side of the image side positive lens group,
The zoom optical system according to any one of claims 1 to 31, wherein the moving lens group moves along an optical axis during zooming.   The zoom optical system according to any one of claims 1 to 32, wherein the first sub lens group is moved in a direction perpendicular to the optical axis. An intermediate lens group is disposed between the object side negative lens group and the positive lens group,
In the comparison of the refractive power based on the absolute value, the refractive power of the intermediate lens group is smaller than the refractive power of the refractive power of the object side negative lens group and smaller than the refractive power of the positive lens group. The zoom optical system according to any one of claims 1 to 33.   The zoom optical system according to claim 34, wherein the intermediate lens group is a moving lens group, and moves along the optical axis during focusing.   The zoom optical system according to any one of claims 1 to 33, wherein the object-side negative lens group and the positive lens group are disposed adjacent to each other.   37. The image side negative lens group having a negative refractive power is disposed between the positive lens group and the image side positive lens group. 37. Zoom optical system.   The zoom optical system according to claim 37, wherein the image-side negative lens group is a moving lens group, and moves along the optical axis during focusing.   The zoom optical system according to claim 37 or 38, wherein the image-side negative lens group does not move along the optical axis during zooming.   The zoom optical system according to claim 37 or 38, wherein the image-side negative lens group is a moving lens group, and moves along the optical axis during zooming. The zoom optical system according to any one of claims 1 to 40, wherein the following conditional expression (17-1) is satisfied.
31.9 ° ≦ ΩHw / 2 ≦ 88.0 ° (17-1)
here,
ΩHw is the horizontal angle of view at the wide-angle end,
It is.   The zoom optical system according to any one of claims 1 to 41, wherein the positive lens group includes a positive lens and a negative lens. The positive lens group includes a first positive lens disposed closest to the object side, and a second positive lens disposed closest to the image side.
43. The zoom optical system according to claim 1, wherein an image-side lens surface of the second positive lens is a convex surface.   43. The zoom optical system according to any one of claims 1 to 42, wherein an overall length of the zoom optical system is constant during zooming.   The zoom optical system according to any one of claims 1 to 44, wherein at the time of zooming, the aperture stop moves only in one direction along the optical axis or does not move.   45. The zoom optical system according to claim 1, wherein the aperture stop does not move along the optical axis during zooming.   The zoom optical system according to any one of claims 1 to 46, wherein a predetermined positive lens group having a positive refractive power is disposed on the object side of the object-side negative lens group. 48. The zoom optical system according to claim 47, wherein the following conditional expression (18) is satisfied.
2.3 ≦ fGP1 / fGPM ≦ 7 (18)
here,
fGP1 is the focal length of the predetermined positive lens group,
fGPM is the focal length of the positive lens group,
It is. The predetermined positive lens group includes a negative lens and a positive lens,
The positive lens of the predetermined positive lens group is a meniscus lens;
49. The zoom optical system according to claim 47, wherein a lens surface on the object side of the meniscus lens is a convex surface on the object side.   The zoom optical system according to any one of claims 47 to 49, wherein the predetermined positive lens group includes a negative lens and two positive lenses. The two positive lenses of the predetermined positive lens group are both meniscus lenses,
51. The zoom optical system according to claim 50, wherein a lens surface on the object side of the meniscus lens is a convex surface on the object side.   52. The zoom optical system according to claim 51, wherein the predetermined positive lens group further includes another positive lens. The zoom optical system according to any one of claims 37 to 40, wherein the following conditional expression (19) is satisfied.
0.5 ≦ | fGPM / fGNB | ≦ 2.0 (19)
here,
fGPM is the focal length of the positive lens group,
fGNB is a focal length of the image-side negative lens unit,
It is. The zoom optical system according to any one of claims 37 to 40, 53, wherein the following conditional expression (20) is satisfied.
0.25 ≦ fGN1 / fGNB ≦ 1.5 (20)
here,
fGN1 is the focal length of the object side negative lens unit,
fGNB is a focal length of the image-side negative lens unit,
It is. The zoom optical system according to any one of claims 1 to 53, wherein the following conditional expression (21) is satisfied.
0.03 ≦ ΔGPMM / LTLw ≦ 0.3 (21)
here,
ΔGPMM is the amount of movement of the positive lens group when moving from the wide-angle end to the telephoto end,
LTLw is the total length of the zoom optical system at the wide-angle end,
It is.   The zoom optical system according to any one of claims 1 to 55, wherein the positive lens group does not move along the optical axis during zooming.   The zoom optical system according to any one of claims 1 to 46, wherein the object-side negative lens group is disposed closest to the object side. The object-side negative lens group includes a first negative meniscus lens, a second negative meniscus lens, and one positive lens.
The first negative meniscus lens is located closest to the object side;
The second negative meniscus lens is located on the image side of the first negative meniscus lens;
58. The object-side lens surface of the first negative meniscus lens and the object-side lens surface of the second negative meniscus lens are both concave surfaces on the image side. The zoom optical system according to any one of claims.   36. The zoom optical system according to claim 34 or 35, wherein the intermediate lens group has a positive refractive power and is disposed closer to the object side than the aperture stop. The zoom optical system according to any one of claims 1 to 59, wherein the following conditional expression (22) is satisfied.
7.0 ≦ ft / fw ≦ 120 (22)
here,
ft is the focal length of the zoom optical system at the telephoto end,
fw is the focal length of the zoom optical system at the wide-angle end,
It is. The zoom optical system according to any one of claims 1 to 59, wherein the following conditional expression (23) is satisfied.
0.6 ≦ FNOw ≦ 4.0 (23)
here,
FNOw is the F number at the wide-angle end,
It is. The zoom optical system according to any one of claims 1 to 61, wherein the following conditional expression (24) is satisfied.
0.7 ≦ FNOt ≦ 5.1 (24)
here,
FNOt is the F number at the telephoto end.
It is. The zoom optical system according to any one of claims 1 to 62, wherein the following conditional expression (25-1) is satisfied.
0.0 ≦ ft / fw + 13.38 × tan (ΩHw / 2) −21.0 ≦ 350 (25-1)
here,
fw is the focal length of the zoom optical system at the wide-angle end,
ft is the focal length of the zoom optical system at the telephoto end,
ΩHw is the horizontal angle of view at the wide-angle end,
It is. 53. The zoom optical system according to claim 47, wherein the following conditional expression (26) is satisfied.
0.04 ≦ ΣGP1 / LTLw ≦ 0.35 (26)
here,
ΣGP1 is the thickness of the predetermined positive lens group,
LTLw is the total length of the zoom optical system at the wide-angle end,
It is. The zoom optical system according to any one of claims 1 to 64, wherein the following conditional expression (27) is satisfied.
−2.3 <fw × FNOw / fGN1 <−0.4 (27)
here,
fw is the focal length of the zoom optical system at the wide-angle end,
FNOw is the F number at the wide-angle end,
fGN1 is the focal length of the object side negative lens unit,
It is. 59. A zoom optical system according to claim 58, wherein the following conditional expression (28) is satisfied.
1.9 <SPGN1Ln1 <6.5 (28)
here,
SPGN1Ln1 is represented by the following equation:
SPGN1Ln1 = (RGN1Ln1f + RGN1Ln1r) / (RGN1Ln1f−RGN1Ln1r)
RGN1Ln1f is a radius of curvature of the object-side lens surface of the first negative meniscus lens,
RGN1Ln1r is a radius of curvature of the image-side lens surface of the first negative meniscus lens,
It is. The zoom optical system according to any one of claims 1 to 65, wherein the following conditional expression (29) is satisfied.
-25% <DTw <5% (29)
here,
DTw is the amount of distortion at the maximum angle of view at the wide-angle end, and is expressed by the following equation:
DTw = (IHw1-IHw2) / IHw2 × 100 (%),
IHw1 is a real image height when a light beam including a light beam having a maximum angle of view forms an image on the image plane,
IHw2 is a paraxial image height when a light beam including a light beam having a maximum angle of view forms an image on the image plane,
In both cases, the image height when focusing on an object point at infinity
It is. Optical system,
An imaging element having an imaging surface and converting an image formed on the imaging surface by the optical system into an electrical signal;
An image pickup apparatus, wherein the optical system is the zoom optical system according to any one of claims 1 to 67. 68. The imaging device according to claim 67, wherein the following conditional expression (30) is satisfied.
3.15 mm ≦ Rimg ≦ 40.0 mm (30)
here,
Rimg is the radius of the image circle in the image sensor,
It is.

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