JP2019132887A - Zoom optical system and image capturing device having the same - Google Patents

Abstract

To provide a zoom optical system which is compact with a short total optical system length, and yet offers high image-forming performance even while making image blur correction, and to provide an image capturing device having the same.SOLUTION: A zoom optical system comprises a first lens group having positive refractive power, a second lens group having negative refractive power, a third lens group having positive refractive power, and a fourth lens group having negative refractive power arranged in order from the object side. The second lens group and the fourth lens group move along an optical axis while zooming. The third lens group comprises a first lens element and a second lens element, the first lens element being located next to the second lens element disposed on the most image side. Only the second lens element is moved in a direction perpendicular to the optical axis to make image blur correction. The zoom optical system satisfies the following conditional expressions (1), (2): -0.05<Δ1G/Δ2G<0.05 ...(1), 0.10<dG3L12/dG3<0.35 ...(2).SELECTED DRAWING: Figure 1

Description

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

  A zooming optical system having a high zooming ratio is disclosed in Patent Document 1, Patent Document 2, and Patent Document 3.

  The variable power optical system disclosed in Patent Document 1 and the variable power optical system disclosed in Patent Document 3 include a first lens group having a positive refractive power and a second lens group having a negative refractive power. And a third lens group having a positive refractive power, a fourth lens group having a negative refractive power, and a fifth lens group G having a positive refractive power. At the time of zooming, the second lens group and the fourth lens group move along the optical axis.

  The variable magnification optical system disclosed in Patent Document 2 includes a first lens group having a positive refractive power, a second lens group having a negative refractive power, and a third lens group having a positive refractive power; The lens unit includes a fourth lens group having negative refractive power and a fifth lens group having positive refractive power. At the time of zooming, the second lens group, the third lens group, and the fourth lens group move.

  In the variable magnification optical system disclosed in Patent Document 1, the third lens group includes a blur correction lens. In the variable magnification optical system disclosed in Patent Document 2, the fifth lens group includes a blur correction lens. The variable magnification optical system disclosed in Patent Document 3 does not include a shake correction lens. The blur correction lens is a lens that moves in a direction orthogonal to the optical axis.

Japanese Patent Laying-Open No. 2017-116678 (first embodiment) Japanese Patent No. 5549134 (first embodiment) Japanese Patent No. 5303310 (first embodiment)

  In the variable magnification optical system disclosed in Patent Document 1, the blur correction lens is located closer to the object side than the lens located closest to the image side in the third lens group. In this case, since the shake correction lens becomes large, a mechanism for moving the shake correction lens becomes large. In addition, since the blur correction lens becomes heavy, it is difficult to perform blur correction at high speed.

  In the variable magnification optical system disclosed in Patent Document 2, the number of lenses constituting the fifth lens group increases. In this case, since the fifth lens group becomes large, the entire length of the optical system becomes long. Further, it is not possible to secure a sufficient movement space for the lens group that moves during zooming. Therefore, a high zoom ratio cannot be obtained.

  In the variable magnification optical system disclosed in Patent Document 3, for example, a blur correction lens can be disposed in the third lens group. In this case, the blur correction lens can be disposed on the most image side of the third lens group. However, the third lens group cannot secure a wide lens interval. For this reason, the height of the axial ray increases at the wide-angle end. If the blur correction lens is moved at a position where the light beam is high, the variation in spherical aberration increases. Therefore, the imaging performance at the time of blur correction deteriorates.

  The present invention has been made in view of such a problem, and has a variable magnification optical system having high imaging performance even at the time of blur correction, and an imaging apparatus including the same, while the overall length of the optical system is short and small The purpose is to provide.

In order to solve the above-described problems and achieve the object, a variable magnification optical system according to at least some embodiments of the present invention includes:
From the object side,
A first lens group having a positive refractive power;
A second lens group having negative refractive power;
A third lens group having positive refractive power;
A fourth lens group having negative refractive power,
During zooming, the second lens group and the fourth lens group move in the optical axis direction,
The third lens group has a first lens element and a second lens element,
The first lens element is located next to the second lens element,
The second lens element is located closest to the image side,
Blur is corrected by moving only the second lens element in the direction perpendicular to the optical axis,
The following conditional expressions (1) and (2) are satisfied.
-0.05 <Δ1G / Δ2G <0.05 (1)
0.10 <dG3L12 / dG3 <0.35 (2)
here,
Δ1G is the amount of movement of the first lens group from the wide-angle end to the telephoto end,
Δ2G is the amount of movement of the second lens group from the wide-angle end to the telephoto end,
dG3L12 is the air spacing between the first lens element and the second lens element,
dG3 is the thickness of the third lens group,
It is.

An imaging device according to at least some embodiments of the present invention
Optical system,
An imaging element 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 the variable magnification optical system described above.

  According to the present invention, it is possible to provide a variable magnification optical system having a high image forming performance even at the time of blur correction and an image pickup apparatus including the same while the total length of the optical system is short and small.

2 is a lens cross-sectional view of a variable magnification optical system according to Example 1. FIG. 6 is a lens cross-sectional view of a variable magnification optical system of Example 2. FIG. 6 is a lens cross-sectional view of a variable magnification optical system according to Example 3. FIG. 6 is a lens cross-sectional view of a variable magnification optical system of Example 4. FIG. 10 is a lens cross-sectional view of a variable magnification optical system of Example 5. FIG. 10 is a lens cross-sectional view of a variable magnification optical system of Example 6. FIG. 10 is a lens cross-sectional view of a variable magnification optical system according to Example 7. FIG. 10 is a lens cross-sectional view of a variable magnification optical system of Example 8. FIG. 10 is a lens cross-sectional view of a variable magnification optical system of Example 9. FIG. 12 is a lens cross-sectional view of a variable magnification optical system according to Example 10. FIG. 12 is a lens cross-sectional view of a variable magnification optical system according to Example 11. FIG. FIG. 3 is an aberration diagram of the variable magnification optical system according to Example 1. 6 is an aberration diagram of the variable magnification optical system according to Example 2. FIG. FIG. 6 is an aberration diagram of the variable magnification optical system according to Example 3. FIG. 6 is an aberration diagram of the variable magnification optical system of Example 4. FIG. 10 is an aberration diagram of the variable magnification optical system of Example 5. 10 is an aberration diagram of the variable magnification optical system of Example 6. FIG. 10 is an aberration diagram of the variable magnification optical system of Example 7. FIG. 10 is an aberration diagram of the variable magnification optical system of Example 8. FIG. 10 is an aberration diagram of the variable magnification optical system of Example 9. FIG. FIG. 10 is an aberration diagram of the variable magnification optical system according to Example 10. FIG. 10 is an aberration diagram of the variable magnification optical system of Example 11. 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.

  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.

The variable magnification optical system of this embodiment includes, in order from the object side, a first lens group having a positive refractive power, a second lens group having a negative refractive power, and a third lens group having a positive refractive power. A fourth lens group having a negative refractive power, and at the time of zooming, the second lens group and the fourth lens group move in the optical axis direction, and the third lens group includes the first lens element and And the second lens element, the first lens element is located next to the second lens element, the second lens element is located closest to the image side, and only the second lens element is perpendicular to the optical axis. The blur is corrected by moving in the direction, and the following conditional expressions (1) and (2) are satisfied.
-0.05 <Δ1G / Δ2G <0.05 (1)
0.10 <dG3L12 / dG3 <0.35 (2)
here,
Δ1G is the amount of movement of the first lens group from the wide-angle end to the telephoto end,
Δ2G is the amount of movement of the second lens group from the wide-angle end to the telephoto end,
dG3L12 is the air spacing between the first lens element and the second lens element,
dG3 is the thickness of the third lens group,
It is.

  The variable magnification optical system of this embodiment includes, in order from the object side, a first lens group having a positive refractive power, a second lens group having a negative refractive power, and a third lens group having a positive refractive power. Have. In the variable magnification optical system of the present embodiment, the lens group having a positive refractive power is located closest to the object side. Therefore, the variable magnification optical system of the present embodiment is a positive leading type optical system.

  The positive-preceding type optical system is an optical system that is advantageous for securing a high zoom ratio and securing a bright F number from the wide-angle end to the telephoto end. Therefore, the zooming optical system of the present embodiment can secure a high zooming ratio and can secure a bright F number from the wide-angle end to the telephoto end.

  By arranging the second lens group having a negative refractive power and the third lens group having a positive refractive power, the diameter of the axial light beam on the image side can be made smaller than that of the third lens group. Therefore, the lens group located on the image side with respect to the third lens group can be downsized.

  At the time of zooming, the second lens group and the fourth lens group move. In the variable magnification optical system of the present embodiment, the magnification is changed mainly by the second lens group, and the image plane variation due to the magnification change is corrected by the fourth lens group.

  As described above, the diameter of the axial light beam is smaller on the image side than the third lens group. Therefore, even if the fourth lens group is moved, fluctuations in spherical aberration and axial chromatic aberration can be suppressed.

  The third lens group includes a first lens element and a second lens element. The first lens element is located next to the second lens element. The second lens element is located closest to the image side.

  In the third lens group, the diameter of the axial light beam is smaller on the image side than on the object side. Therefore, only the second lens element is moved in the direction perpendicular to the optical axis. Since the diameter of the axial light beam is small at the position of the second lens element, the second lens element can be reduced in size. In this case, since the second lens element can be lightened, blurring can be corrected at high speed.

  Further, the second lens element is farther from the image plane than the fourth lens group. Therefore, the height of the off-axis light beam at the position of the second lens element is lower than the height of the off-axis light beam at the position of the fourth lens group. As a result, fluctuations in astigmatism during blur correction can be suppressed.

  Conditional expression (1) is a conditional expression relating to the ratio between the amount of movement of the first lens group during zooming and the amount of movement of the second lens group during zooming. The amount of movement is the amount of movement from the wide-angle end to the telephoto end. When the lens group moves to the image side, the movement amount becomes a positive value.

  By satisfying conditional expression (1), the movement of the first lens group relative to the second lens group can be suppressed. By reducing the amount of movement of the first lens group relative to the amount of movement of the second lens group, manufacturing errors can be reduced and the moving mechanism can be simplified.

  When the value exceeds the lower limit value of the conditional expression (1), the movement of the first lens group, for example, the movement toward the object side can be suppressed. Therefore, the total length of the optical system can be shortened. When the value is lower than the upper limit value of conditional expression (1), the movement of the first lens group, for example, the movement toward the image side can be suppressed. Therefore, a sufficient zoom ratio can be ensured in the second lens group.

  When the value exceeds the lower limit value of the conditional expression (2), the air gap between the first lens element and the second lens element can be widened. In this case, since the height of the axial ray passing through the second lens element can be lowered, it is possible to suppress the variation in spherical aberration during blur correction.

  When the value is lower than the upper limit value of the conditional expression (2), the air gap between the first lens element and the second lens element can be narrowed. In this case, the second lens element can be made small while maintaining high blur correction sensitivity. As a result, the third lens group can also be made small.

In the variable magnification optical system of the present embodiment, it is preferable that the second lens element is a positive lens and satisfies the following conditional expression (3).
0.800 <| fG3L2 / fG3 | <2.500 (3)
here,
fG3L2 is the focal length of the second lens element,
fG3 is the focal length of the third lens group,
It is.

  Conditional expression (3) is a conditional expression relating to the ratio between the focal length of the second lens element and the focal length of the third lens unit.

  When the value exceeds the lower limit value of conditional expression (3), the focal length of the second lens element becomes longer than the focal length of the third lens group. Therefore, the generation of astigmatism at the wide angle end can be suppressed.

  When the value is lower than the upper limit value of the conditional expression (3), the focal length of the second lens element becomes shorter than the focal length of the third lens group. In this case, the height of the off-axis light beam incident on the fourth lens group can be reduced. Therefore, the fourth lens group can be made small.

In the variable magnification optical system of the present embodiment, it is preferable that the third lens group has an object-side positive lens closest to the object side and satisfies the following conditional expression (4).
0.400 <| fG3Lo / fG3 | <1.200 (4)
here,
fG3Lo is the focal length of the object side positive lens,
fG3 is the focal length of the third lens group,
It is.

  Conditional expression (4) is a conditional expression regarding the ratio of the focal length of the object side positive lens to the focal length of the third lens unit.

  When the value exceeds the lower limit value of the conditional expression (4), the focal length of the object side positive lens becomes longer than the focal length of the third lens group. Therefore, it is possible to suppress the occurrence of spherical aberration at the wide angle end.

  When the value is lower than the upper limit value of the conditional expression (4), the focal length of the object side positive lens becomes shorter than the focal length of the third lens group. In this case, at the wide-angle end, the height of the axial ray within the third lens group, for example, the height of the axial ray closer to the image side than the object-side positive lens can be suppressed. Therefore, the diameter of the lens located on the image side from the object side positive lens can be reduced.

In the variable magnification optical system of the present embodiment, it is preferable that the second lens element is a positive lens and satisfies the following conditional expression (5).
-4 <SFG3L2 <-0.25 (5)
here,
SFG3L2 = (RG3L2o + RG3L2i) / (RG3L2o−RG3L2i),
RG3L2o is the radius of curvature of the object side surface of the second lens element,
RG3L2i is the radius of curvature of the image side surface of the second lens element,
It is.

  Conditional expression (5) is a conditional expression related to the shaping factor of the second lens element.

  When the value exceeds the lower limit value of the conditional expression (5), the positive refractive power on the object side lens surface of the second lens element can be reduced. Therefore, the generation of astigmatism can be suppressed.

  When the value is lower than the upper limit value of the conditional expression (5), the positive refractive power on the object side lens surface of the second lens element can be increased. Therefore, the generation of spherical aberration can be suppressed.

The variable magnification optical system of the present embodiment preferably satisfies the following conditional expressions (6) and (7).
0.300 <| (1-βG3L2w) × βbackw | <1.000 (6)
0.500 <| (1-βG3L2t) × βbackt | <2.000 (7)
here,
βG3L2w is the lateral magnification of the second lens element at the wide-angle end,
βG3L2t is the lateral magnification of the second lens element at the telephoto end,
βbackw is the lateral magnification of a predetermined lens group at the wide-angle end,
βbackt is the lateral magnification of a predetermined lens group at the telephoto end,
The horizontal magnification is the horizontal magnification when focusing on an object point at infinity,
The predetermined lens group is a lens group composed of all lenses located on the image side of the third lens group,
It is.

  When the value exceeds the lower limit value of conditional expression (6), the effect of blur correction can be improved. When the value is lower than the upper limit value of conditional expression (6), the occurrence of spherical aberration at the positive lens in the third lens group can be suppressed at both the wide-angle end and the telephoto end.

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

  In the variable magnification optical system according to the present embodiment, it is preferable that the third lens group includes three positive lens elements and at least one negative lens element.

  By using three positive lens elements for the third lens group, the positive refractive power of the third lens group can be shared by the three lens elements. As a result, even when the refractive power of the third lens group is increased, the occurrence of spherical aberration at the wide angle end can be suppressed.

  By using one or more negative lens elements in the third lens group, axial chromatic aberration generated in the positive lens can be corrected. In addition, it is possible to suppress the occurrence of axial chromatic aberration in the third lens group.

  The zoom optical system of the present embodiment preferably has an aperture stop that limits the axial light beam, and the aperture stop is preferably located between the second lens group and the image side surface of the third lens group.

  By arranging the aperture stop between the second lens group and the third lens group or in the third lens group, the axial beam diameter on the image side of the third lens group can be suppressed. it can.

  As described above, at the time of zooming, the fourth lens group moves in the optical axis direction. Since the fourth lens group is located closer to the image side than the third lens group, the fourth lens group moves in a place where the axial beam diameter is small. Therefore, it is possible to correct the image plane variation while suppressing the variation in spherical aberration and the variation in longitudinal chromatic aberration during zooming.

The variable magnification optical system of the present embodiment preferably satisfies the following conditional expression (8).
2.00 <fG3 / fw <5.50 (8)
here,
fG3 is the focal length of the third lens group,
fw is the focal length of the variable magnification optical system at the wide angle end,
It is.

  Conditional expression (8) is a conditional expression relating to the ratio between the focal length of the third lens group and the focal length of the variable magnification optical system at the wide-angle end.

  When the value exceeds the lower limit value of conditional expression (8), the focal length of the third lens group becomes longer than the focal length of the variable magnification optical system at the wide angle end. In this case, since the refractive power of the third lens group can be reduced, the occurrence of spherical aberration in the third lens group can be suppressed at the wide angle end.

  When the value is lower than the upper limit value of conditional expression (8), the focal length of the third lens group becomes shorter than the focal length of the variable magnification optical system at the wide angle end. In this case, since the refractive power of the third lens group can be increased, the length of the lens group positioned closer to the image side than the third lens group can be shortened.

The variable magnification optical system of the present embodiment preferably satisfies the following conditional expression (9).
0.070 <fG3 / ft <0.170 (9)
here,
fG3 is the focal length of the third lens group,
ft is the focal length of the variable magnification optical system at the telephoto end,
It is.

  Conditional expression (9) is a conditional expression relating to the ratio between the focal length of the third lens group and the focal length of the variable magnification optical system at the telephoto end.

  When the value exceeds the lower limit value of conditional expression (9), the focal length of the third lens group becomes longer than the focal length of the variable magnification optical system at the telephoto end. In this case, since the refractive power of the third lens group can be reduced, the occurrence of spherical aberration in the third lens group can be suppressed at the wide angle end.

  When the value is less than the upper limit value of conditional expression (9), the focal length of the third lens group becomes shorter than the focal length of the variable magnification optical system at the telephoto end. In this case, since the refractive power of the third lens group can be increased, the length of the lens group positioned closer to the image side than the third lens group can be shortened.

The variable magnification optical system according to the present embodiment preferably satisfies the following conditional expression (10).
10 <β2Gt / β2Gw <40 (10)
here,
β2Gt is the lateral magnification of the second lens group at the telephoto end,
β2Gw is the lateral magnification of the second lens group at the wide-angle end,
The magnification is the magnification when focusing on an object point at infinity,
It is.

  Conditional expression (10) is a conditional expression regarding the zoom ratio of the second lens unit.

  When the value exceeds the lower limit value of conditional expression (10), the zooming effect in the second lens group can be increased. In this case, since the zooming burden in the lens group other than the second lens group can be reduced, the movement amount of the lens group other than the second lens group can be suppressed. When the movement amount of the lens group is suppressed, the space in which the lens group moves can be reduced on the image side than the second lens group. Therefore, the total length of the optical system can be shortened.

  On the wide-angle side, movement of the second lens group tends to increase distortion distortion, astigmatism fluctuation, and lateral chromatic aberration fluctuation. Therefore, it is preferable that fluctuations of these aberrations are suppressed on the wide angle side.

  When the value is lower than the upper limit value of conditional expression (10), the zooming effect in the second lens group can be reduced. In this case, the movement amount of the second lens group can be suppressed. Therefore, it is possible to maintain good imaging performance while suppressing fluctuations in various aberrations at the time of zooming, particularly fluctuations in distortion, fluctuations in astigmatism, and fluctuations in lateral chromatic aberration.

The variable magnification optical system of the present embodiment preferably satisfies the following conditional expression (11).
0.040 <dG3L12 / fG3L2 <0.400 (11)
here,
dG3L12 is the air spacing between the first lens element and the second lens element,
fG3L2 is the focal length of the second lens element,
It is.

  Conditional expression (11) is a conditional expression relating to the ratio between the air distance between the first lens element and the second lens element and the focal length of the second lens element.

  When the value exceeds the lower limit value of the conditional expression (11), the focal distance of the second lens element can be shortened while widening the air gap between the first lens element and the second lens element. In this case, the refractive power of the second lens element can be increased. Therefore, the blur correction sensitivity can be increased without deteriorating the spherical aberration at the wide angle end.

  When the value is lower than the upper limit value of conditional expression (11), the air gap between the first lens element and the second lens element can be suppressed. As a result, the third lens group can be made smaller.

In the variable magnification optical system of the present embodiment, it is preferable that the first lens group has at least one negative lens that satisfies the following conditional expressions (12) and (13).
24 <νd1Gn <56 (12)
0.53 <θg, F1Gn <0.62 (13)
here,
νd1Gn is the maximum Abbe number among the Abbe numbers of the negative lenses included in the first lens group,
θg, F1Gn is the minimum partial dispersion ratio among the partial dispersion ratios of the negative lens included in the first lens group,
The partial dispersion ratio is expressed by θg, F1Gn = (ng1Gn−nF1Gn) / (nF1Gn−nC1Gn),
ng1Gn, nF1Gn, and nC1Gn are the refractive index for g-line, the refractive index for F-line, the refractive index for C-line,
It is.

  Conditional expression (12) is a conditional expression regarding the Abbe number of the negative lens of the first lens group.

  In the first lens group, it is preferable that the negative refractive power is appropriately ensured while ensuring the positive refractive power as a whole.

  When the value exceeds the lower limit value of the conditional expression (12), it is possible to appropriately secure a negative refractive power while suppressing the occurrence of chromatic aberration in the first lens group. As a result, the occurrence of astigmatism on the telephoto side can be suppressed.

  When the value is lower than the upper limit value of conditional expression (12), the occurrence of chromatic aberration in the first lens group can be suppressed. As a result, good imaging performance can be maintained.

  Conditional expression (13) is a conditional expression related to partial dispersion of the negative lens of the first lens group.

  When the value exceeds the lower limit value of conditional expression (13), the glass material effective for correcting chromatic aberration increases. Since the number of selectable glass materials increases, chromatic aberration can be favorably corrected.

  At the telephoto end, chromatic aberration of g-line with respect to F-line is likely to occur in the first lens group. Therefore, it is preferable to suppress the occurrence of this chromatic aberration.

  When the value is lower than the upper limit value of conditional expression (13), the occurrence of chromatic aberration of g-line with respect to F-line in the first lens group can be suppressed. As a result, good imaging performance can be maintained.

  In the variable magnification optical system of the present embodiment, it is preferable that only the fourth lens group moves to the image side when focusing from an infinite object point to a close object point.

  By moving only the fourth lens group, the focusing mechanism can be simplified. In addition, the beam diameter is small near the image plane. Since the fourth lens group is located near the image plane, the fourth lens group can be made smaller and lighter. By using the fourth lens group as the focusing lens group, a light focusing lens group having a small diameter can be realized. As a result, a fast focusing speed can be secured.

  In the zoom optical system of the present embodiment, it is preferable that the first lens unit is fixed during zooming.

  By doing so, the first lens group is always fixed with respect to the image plane. As a result, manufacturing errors can be further reduced, and the mechanical configuration can be further simplified.

The variable magnification optical system according to the present embodiment preferably satisfies the following conditional expression (14).
19 <ft / fw <50 (14)
here,
ft is the focal length of the variable magnification optical system at the telephoto end,
fw is the focal length of the variable magnification optical system at the wide angle end,
It is.

  When the value exceeds the lower limit value of the conditional expression (14), a high zoom ratio can be secured. When the value is lower than the upper limit value of conditional expression (14), the occurrence of various aberrations can be suppressed.

  The imaging apparatus of the present embodiment includes an optical system and an imaging element that has an imaging surface and converts an image formed on the imaging surface by the optical system into an electrical signal, and the optical system is the above-described embodiment. This is a variable magnification optical system.

  According to the image pickup apparatus of the present embodiment, an image in which chromatic aberration is favorably corrected can be acquired even though it is a small apparatus.

  As for the above-mentioned composition, it is more preferred to satisfy a plurality simultaneously mutually. Moreover, you may make it satisfy some structures simultaneously. For example, any of the above-described other variable magnification optical systems may be used in any of the above-described variable magnification optical systems.

  As for the conditional expressions, each conditional expression may be satisfied individually. This is preferable because each effect can be easily obtained.

For each conditional expression, the lower limit value or the upper limit value may be changed as follows. This is preferable because the effect of each conditional expression can be further ensured.
Conditional expression (1) is as follows.
It is preferable to set the lower limit to −0.03 or −0.01.
The upper limit is preferably set to 0.03 or 0.01.
Conditional expression (2) is as follows.
It is preferable to set the lower limit to 0.12 or 0.15.
The upper limit is preferably set to 0.30 or 0.28.
Conditional expression (3) is as follows.
The lower limit value is preferably 1.000 or 1.100.
It is preferable to set the upper limit to 2.300 or 1.700.
Conditional expression (4) is as follows.
The lower limit value is preferably set to 0.600 or 0.650.
The upper limit is preferably 1.000 or 0.950.
Conditional expression (5) is as follows.
It is preferable to set the lower limit to −2.7 or −1.6.
It is preferable to set the upper limit to −0.5 or −1.0.
Conditional expression (6) is as follows.
The lower limit is preferably set to 0.350 or 0.400.
The upper limit is preferably set to 0.800 or 0.750.
Conditional expression (7) is as follows.
The lower limit value is preferably set to 0.550 or 0.600.
The upper limit is preferably set to 1.700 or 1.500.
Conditional expression (8) is as follows.
It is preferable to set the lower limit to 2.30 or 2.60.
The upper limit is preferably set to 5.00 or 4.70.
Conditional expression (9) is as follows.
The lower limit is preferably 0.080 or 0.090.
The upper limit is preferably set to 0.150 or 0.130.
Conditional expression (10) is as follows.
The lower limit is preferably 12 or 15.
The upper limit is preferably 35 or 30.
Conditional expression (11) is as follows.
The lower limit is preferably set to 0.060 or 0.080.
The upper limit is preferably set to 0.300 or 0.200.
Conditional expression (12) is as follows.
The lower limit is preferably set to 36 or 40.
Conditional expression (13) is as follows.

  Hereinafter, embodiments of the variable magnification optical system will be described in detail with reference to the drawings. Note that the present invention is not limited to the embodiments.

  The lens cross-sectional view of each example shows a lens cross-sectional view at the wide-angle 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 (DT) in the intermediate focal length state, and (h) is The lateral chromatic aberration (CC) in the intermediate focal length state is shown.

  (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.

  The lens cross-sectional view is a lens cross-sectional view when focusing on an object point at infinity. The aberration diagram is an aberration diagram at the time of focusing on an object point at infinity.

  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 aperture stop is S, and the image plane (imaging surface) is I. It is.

  The variable magnification optical system of Example 1 includes, in order from the object side, a first lens group G1 having a positive refractive power, a second lens group G2 having a negative refractive power, and a third lens having a positive refractive power. It includes a group G3, 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, a positive meniscus lens L3 having a convex surface facing the object side, and a convex surface facing the object side. And a positive meniscus lens L4. Here, the negative meniscus lens L1 and the positive meniscus lens L2 are cemented.

  The second lens group G2 includes a negative meniscus lens L5 having a convex surface facing the object side, a biconcave negative lens L6, a positive meniscus lens L7 having a convex surface facing the object side, and a negative meniscus lens having a convex surface facing the image side. L8. Here, the biconcave negative lens L6 and the positive meniscus lens L7 are cemented.

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

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

  The fifth lens group G5 is composed of a biconvex positive lens L15.

  At the time of zooming from the wide angle end to the telephoto end, the first lens group G1 and the fifth lens group G5 are fixed. The second lens group G2 moves to the image side. The third lens group G3 and the fourth lens group G4 move to the object side. The aperture stop S moves together with the third lens group G3.

  When focusing from an infinite object point to a close object point, the fourth lens group G4 moves to the image side.

  The aspheric surfaces are the object side surface of the biconcave negative lens L6, both surfaces of the biconvex positive lens L9, the image side surface of the biconvex positive lens L11, the image side surface of the biconcave negative lens L14, and both surfaces of the biconvex positive lens L15. And a total of seven surfaces.

  The variable magnification 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 having a positive refractive power. It includes a group G3, 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, a positive meniscus lens L3 having a convex surface facing the object side, and a convex surface facing the object side. And a positive meniscus lens L4. Here, the negative meniscus lens L1 and the positive meniscus lens L2 are cemented.

  The second lens group G2 includes a negative meniscus lens L5 having a convex surface facing the object side, a biconcave negative lens L6, a positive meniscus lens L7 having a convex surface facing the object side, and a negative meniscus lens having a convex surface facing the image side. L8. Here, the biconcave negative lens L6 and the positive meniscus lens L7 are cemented.

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

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

  The fifth lens group G5 is composed of a biconvex positive lens L15.

  At the time of zooming from the wide angle end to the telephoto end, the first lens group G1 and the fifth lens group G5 are fixed. The second lens group G2 moves to the image side. The third lens group G3 and the fourth lens group G4 move to the object side. The aperture stop S moves together with the third lens group G3.

  When focusing from an infinite object point to a close object point, the fourth lens group G4 moves to the image side.

  The aspheric surfaces are the object side surface of the biconcave negative lens L6, both surfaces of the biconvex positive lens L9, the image side surface of the biconvex positive lens L11, the image side surface of the biconcave negative lens L14, and both surfaces of the biconvex positive lens L15. And a total of seven surfaces.

  The variable magnification 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 having a positive refractive power. It includes a group G3, 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 biconcave negative lens L5, a biconcave negative lens L6, and a biconvex positive lens L7. Here, the biconcave negative lens L6 and the biconvex positive lens L7 are cemented.

  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, a negative meniscus lens L10 having a convex surface directed toward the object side, a biconvex positive lens L11, and an object side. And a positive meniscus lens L12 having a convex surface. Here, the negative meniscus lens L10 and the biconvex positive lens L11 are cemented.

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

  The fifth lens group G5 is composed of a biconvex positive lens L15.

  At the time of zooming from the wide angle end to the telephoto end, the first lens group G1 and the fifth lens group G5 are fixed. The second lens group G2 moves to the image side. The third lens group G3 moves toward the object side from the wide-angle end to the intermediate focal length state, and is fixed from the intermediate focal length state to the telephoto end. The fourth lens group G4 moves to the object side. The aperture stop S moves together with the third lens group G3.

  When focusing from an infinite object point to a close object point, the fourth lens group G4 moves to the image side.

  The aspheric surfaces are provided on a total of seven surfaces including both surfaces of the biconcave negative lens L5, both surfaces of the biconvex positive lens L8, the image side surface of the biconcave negative lens L14, and both surfaces of the biconvex positive lens L15. .

  The variable magnification optical system of Example 4 includes, in order from the object side, a first lens group G1 having a positive refractive power, a second lens group G2 having a negative refractive power, and a third lens having a positive refractive power. It includes a group G3, 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 biconcave negative lens L5, a biconcave negative lens L6, and a biconvex positive lens L7. Here, the biconcave negative 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 negative meniscus lens L10 having a convex surface facing the object side, a biconvex positive lens L11, and a positive meniscus having a convex surface facing the object side. And a lens L12. Here, the negative meniscus lens L10 and the biconvex positive lens L11 are cemented.

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

  The fifth lens group G5 is composed of a biconvex positive lens L15.

  At the time of zooming from the wide angle end to the telephoto end, the first lens group G1 and the fifth lens group G5 are fixed. The second lens group G2 moves to the image side. The third lens group G3 and the fourth lens group G4 move to the object side. The aperture stop S moves together with the third lens group G3.

  When focusing from an infinite object point to a close object point, the fourth lens group G4 moves to the image side.

  The aspheric surfaces are provided on a total of seven surfaces including both surfaces of the biconcave negative lens L5, both surfaces of the biconvex positive lens L8, the image side surface of the biconcave negative lens L14, and both surfaces of the biconvex positive lens L15. .

  The variable magnification optical system of Example 5 includes, in order from the object side, a first lens group G1 having a positive refractive power, a second lens group G2 having a negative refractive power, and a third lens having a positive refractive power. It includes a group G3, 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 biconcave negative lens L5, a biconcave negative lens L6, and a biconvex positive lens L7. Here, the biconcave negative 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 negative meniscus lens L10 having a convex surface facing the object side, a biconvex positive lens L11, and a positive meniscus having a convex surface facing the object side. And a lens L12. Here, the negative meniscus lens L10 and the biconvex positive lens L11 are cemented.

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

  The fifth lens group G5 is composed of a biconvex positive lens L15.

  At the time of zooming from the wide angle end to the telephoto end, the first lens group G1 and the fifth lens group G5 are fixed. The second lens group G2 moves to the image side. The third lens group G3 and the fourth lens group G4 move to the object side. The aperture stop S moves together with the third lens group G3.

  When focusing from an infinite object point to a close object point, the fourth lens group G4 moves to the image side.

  The aspheric surfaces are provided on a total of seven surfaces including both surfaces of the biconcave negative lens L5, both surfaces of the biconvex positive lens L8, the image side surface of the biconcave negative lens L14, and both surfaces of the biconvex positive lens L15. .

  The variable magnification 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 having a positive refractive power. It includes a group G3, a fourth lens group G4 having negative refractive power, and a fifth lens group G5 having negative 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 biconcave negative lens L5, a biconcave negative lens L6, and a biconvex positive lens L7. Here, the biconcave negative 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 negative meniscus lens L10 having a convex surface facing the object side, a biconvex positive lens L11, and a biconvex positive lens L12. Has been. Here, the negative meniscus lens L10 and the biconvex positive lens L11 are cemented.

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

  The fifth lens group G5 includes a negative meniscus lens L15 having a convex surface directed toward the object side, and a biconvex positive lens L16.

  At the time of zooming from the wide angle end to the telephoto end, the first lens group G1 and the fifth lens group G5 are fixed. The second lens group G2 moves to the image side. The third lens group G3 and the fourth lens group G4 move to the object side. The aperture stop S moves together with the third lens group G3.

  When focusing from an infinite object point to a close object point, the fourth lens group G4 moves to the image side.

  The aspheric surfaces are provided on a total of six surfaces including both surfaces of the biconcave negative lens L5, both surfaces of the biconvex positive lens L8, the image side surface of the biconcave negative lens L14, and the object side surface of the negative meniscus lens L15. .

  The variable magnification 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 having a positive refractive power. It includes a group G3, a fourth lens group G4 having negative refractive power, and a fifth lens group G5 having negative 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 biconcave negative lens L5, a biconcave negative lens L6, and a biconvex positive lens L7. Here, the biconcave negative 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 negative meniscus lens L10 having a convex surface facing the object side, a biconvex positive lens L11, and a biconvex positive lens L12. Has been. Here, the negative meniscus lens L10 and the biconvex positive lens L11 are cemented.

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

  The fifth lens group G5 includes a negative meniscus lens L15 having a convex surface directed toward the object side, and a biconvex positive lens L16. Here, the negative meniscus lens L15 and the biconvex positive lens L16 are cemented.

  At the time of zooming from the wide angle end to the telephoto end, the first lens group G1 and the fifth lens group G5 are fixed. The second lens group G2 moves to the image side. The third lens group G3 and the fourth lens group G4 move to the object side. The aperture stop S moves together with the third lens group G3.

  When focusing from an infinite object point to a close object point, the fourth lens group G4 moves to the image side.

  The aspheric surfaces are provided on a total of six surfaces including both surfaces of the biconcave negative lens L5, both surfaces of the biconvex positive lens L8, the image side surface of the biconcave negative lens L14, and the object side surface of the negative meniscus lens L15. .

  The variable magnification optical system of Example 8 includes, in order from the object side, a first lens group G1 having a positive refractive power, a second lens group G2 having a negative refractive power, and a third lens having a positive refractive power. It includes a group G3, 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 biconcave negative lens L5, a biconcave negative lens L6, and a biconvex positive lens L7. Here, the biconcave negative lens L6 and the biconvex positive lens L7 are cemented.

  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, a negative meniscus lens L10 having a convex surface directed toward the object side, a biconvex positive lens L11, and an object side. And a positive meniscus lens L12 having a convex surface. Here, the negative meniscus lens L10 and the biconvex positive lens L11 are cemented.

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

  The fifth lens group G5 is composed of a biconvex positive lens L15.

  At the time of zooming from the wide angle end to the telephoto end, the first lens group G1 and the fifth lens group G5 are fixed. The second lens group G2 moves to the image side. The third lens group G3 and the fourth lens group G4 move to the object side. The aperture stop S moves together with the third lens group G3.

  When focusing from an infinite object point to a close object point, the fourth lens group G4 moves to the image side.

  The aspheric surfaces are provided on a total of seven surfaces including both surfaces of the biconcave negative lens L5, both surfaces of the biconvex positive lens L8, the image side surface of the biconcave negative lens L14, and both surfaces of the biconvex positive lens L15. .

  The variable magnification optical system of Example 9 includes, in order from the object side, a first lens group G1 having a positive refractive power, a second lens group G2 having a negative refractive power, and a third lens having a positive refractive power. It includes a group G3, 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 biconcave negative lens L5, a biconcave negative lens L6, and a biconvex positive lens L7. Here, the biconcave negative 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 negative meniscus lens L10 having a convex surface facing the object side, a biconvex positive lens L11, and a biconvex positive lens L12. Has been. Here, the negative meniscus lens L10 and the biconvex positive lens L11 are cemented.

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

  The fifth lens group G5 includes a negative meniscus lens L15 having a convex surface directed toward the object side, and a biconvex positive lens L16.

  At the time of zooming from the wide angle end to the telephoto end, the first lens group G1 and the fifth lens group G5 are fixed. The second lens group G2 moves to the image side. The third lens group G3 and the fourth lens group G4 move to the object side. The aperture stop S moves together with the third lens group G3.

  When focusing from an infinite object point to a close object point, the fourth lens group G4 moves to the image side.

  The aspheric surfaces are provided on a total of six surfaces including both surfaces of the biconcave negative lens L5, both surfaces of the biconvex positive lens L8, the image side surface of the biconcave negative lens L14, and the object side surface of the negative meniscus lens L15. .

  The variable magnification optical system of Example 10 includes, in order from the object side, a first lens group G1 having a positive refractive power, a second lens group G2 having a negative refractive power, and a third lens having a positive refractive power. The lens unit G3 includes a group G3 and a fourth lens group G4 having a negative 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 biconcave negative lens L5, a biconcave negative lens L6, and a biconvex positive lens L7. Here, the biconcave negative 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 negative meniscus lens L10 having a convex surface facing the object side, a biconvex positive lens L11, and a biconvex positive lens L12. Has been. Here, the negative meniscus lens L10 and the biconvex positive lens L11 are cemented.

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

  At the time of zooming from the wide angle end to the telephoto end, the first lens group G1 is fixed. The second lens group G2 moves to the image side. The third lens group G3 and the fourth lens group G4 move to the object side. The aperture stop S moves together with the third lens group G3.

  When focusing from an infinite object point to a close object point, the fourth lens group G4 moves to the image side.

  The aspheric surfaces are provided on a total of six surfaces including both surfaces of the biconcave negative lens L5, both surfaces of the biconvex positive lens L8, the image side surface of the biconvex positive lens L12, and the image side surface of the biconcave negative lens L14. Yes.

  The variable magnification optical system of Example 11 includes, in order from the object side, a first lens group G1 having a positive refractive power, a second lens group G2 having a negative refractive power, and a third lens having a positive refractive power. It includes a group G3, 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 biconcave negative lens L5, a biconcave negative lens L6, and a biconvex positive lens L7. Here, the biconcave negative lens L6 and the biconvex positive lens L7 are cemented.

  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, a negative meniscus lens L10 having a convex surface directed toward the object side, a biconvex positive lens L11, and an object side. And a positive meniscus lens L12 having a convex surface. Here, the negative meniscus lens L10 and the biconvex positive lens L11 are cemented.

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

  The fifth lens group G5 is composed of a biconvex positive lens L15.

  During zooming from the wide-angle end to the telephoto end, the first lens group G1 is fixed from the wide-angle end to the intermediate focal length state, and moves to the object side from the intermediate focal length state to the telephoto end. The second lens group G2 moves to the image side. The third lens group G3 and the fourth lens group G4 move to the object side. The fifth lens group G5 is fixed. The aperture stop S moves together with the third lens group G3.

  When focusing from an infinite object point to a close object point, the fourth lens group G4 moves to the image side.

  The aspheric surfaces are provided on a total of seven surfaces including both surfaces of the biconcave negative lens L5, both surfaces of the biconvex positive lens L8, the image side surface of the biconcave negative lens L14, and both surfaces of the biconvex positive lens L15. .

  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 entire system, FNO. Is the F number, ω is the half field angle, BF is the back focus, and LTL is the total length of the optical system. The back focus represents the distance from the lens surface closest to the image side to the paraxial image surface in terms of air. 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.

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 57.633 1.40 1.85478 24.80
2 38.572 5.93 1.43875 94.93
3 490.001 0.18
4 36.363 4.14 1.49700 81.54
5 188.906 0.18
6 29.512 2.93 1.49700 81.54
7 68.414 Variable
8 88.150 0.50 2.00100 29.13
9 8.614 4.14
10 * -25.698 0.50 1.49710 81.56
11 11.879 2.77 1.94595 17.98
12 94.253 1.18
13 -22.729 0.50 1.80400 46.58
14 -85.330 Variable
15 (Aperture) ∞ 0.00
16 * 10.194 4.39 1.74320 49.34
17 * -243.497 2.51
18 -181.491 0.50 1.85025 30.05
19 7.800 5.41 1.49710 81.56
20 * -17.733 3.01
21 9.010 1.70 1.49710 81.56
22 20.096 Variable
23 -65.198 1.51 1.80810 22.76
24 -11.327 0.40 1.80625 40.91
25 * 11.895 Variable
26 * 26.662 1.90 1.49710 81.56
27 * -11.036 0.30
28 ∞ 2.12 1.51633 64.14
29 ∞ 2.13
Imaging surface ∞

Aspheric data 10th surface
k = 0.000
A4 = 7.11948e-06, A6 = -1.97071e-07, A8 = 9.24421e-10,
A10 = -7.41300e-11
16th page
k = 0.000
A4 = -3.85831e-05, A6 = 1.37977e-08, A8 = -3.03550e-09,
A10 = 9.74886e-12
17th page
k = 0.000
A4 = 6.30997e-05, A6 = 1.11002e-07, A8 = -4.07565e-09,
A10 = 3.25070e-11
20th page
k = 0.000
A4 = 1.45167e-04, A6 = 2.38984e-06, A8 = -4.76218e-08,
A10 = 2.90285e-09
25th page
k = 0.000
A4 = -5.66474e-05, A6 = 2.31002e-06, A8 = 6.32569e-09
26th page
k = 0.000
A4 = -3.70123e-04, A6 = -1.70588e-05, A8 = -5.47215e-07
No. 27
k = 0.000
A4 = 2.53570e-04, A6 = -2.81699e-05, A8 = -1.69955e-07

Zoom data

Zoom ratio 22.00

Wide angle end Medium telephoto end f 5.30 24.86 116.63
FNO. 1.62 3.40 4.51
2ω 70.93 15.87 3.36
IH 3.60 3.60 3.60
BF (in air) 3.84 3.84 3.84
LTL (in air) 89.29 89.29 89.29

d7 0.60 15.86 26.05
d14 34.78 13.09 2.28
d22 2.01 6.16 2.00
d25 2.40 4.68 9.46

Each group focal length
f1 = 42.75 f2 = -7.36 f3 = 14.76 f4 = -12.36 f5 = 15.97

Numerical example 2
Unit mm

Surface data Surface number rd nd νd
Object ∞ ∞
1 60.529 1.40 1.85478 24.80
2 39.609 6.04 1.43875 94.93
3 942.077 0.18
4 36.341 4.16 1.49700 81.54
5 190.377 0.18
6 29.305 2.96 1.49700 81.54
7 67.794 Variable
8 87.378 0.50 2.00100 29.13
9 8.505 3.99
10 * -31.916 0.50 1.49710 81.56
11 11.042 2.82 1.94595 17.98
12 67.930 1.23
13 -22.222 0.50 1.80400 46.58
14 -121.906 Variable
15 (Aperture) ∞ 0.00
16 * 10.216 4.50 1.74320 49.34
17 * -234.105 2.43
18 -265.801 0.50 1.85025 30.05
19 7.800 5.41 1.49710 81.56
20 * -18.000 2.99
21 8.963 1.73 1.49710 81.56
22 19.620 Variable
23 -72.803 1.52 1.80810 22.76
24 -11.498 0.40 1.80625 40.91
25 * 11.015 Variable
26 * 26.570 1.97 1.49710 81.56
27 * -10.578 0.30
28 ∞ 2.12 1.51633 64.14
29 ∞ 2.13
Imaging surface ∞

Aspheric data 10th surface
k = 0.000
A4 = 7.84635e-06, A6 = -3.51089e-07, A8 = 4.58848e-09,
A10 = -9.80301e-11
16th page
k = 0.000
A4 = -3.99790e-05, A6 = 1.41009e-08, A8 = -3.21870e-09,
A10 = 9.91084e-12
17th page
k = 0.000
A4 = 6.38132e-05, A6 = 1.17445e-07, A8 = -4.30311e-09,
A10 = 3.54323e-11
20th page
k = 0.000
A4 = 1.44012e-04, A6 = 2.41475e-06, A8 = -5.36044e-08,
A10 = 3.02832e-09
25th page
k = 0.000
A4 = -5.59992e-05, A6 = 3.01217e-06, A8 = 1.95297e-08
26th page
k = 0.000
A4 = -3.69824e-04, A6 = -2.32267e-05, A8 = -4.24190e-07
No. 27
k = 0.000
A4 = 2.38599e-04, A6 = -3.23880e-05, A8 = -8.14732e-08

Zoom data

Zoom ratio 23.00

Wide angle end Medium telephoto end f 5.28 25.31 121.50
FNO. 1.63 3.40 4.50
2ω 70.82 15.58 3.23
IH 3.60 3.60 3.60
BF (in air) 3.84 3.84 3.84
LTL (in air) 89.29 89.29 89.29

d7 0.60 16.01 26.18
d14 34.54 12.74 2.28
d22 2.00 6.61 2.00
d25 2.40 4.19 9.09

Each group focal length
f1 = 42.56 f2 = -7.17 f3 = 14.65 f4 = -11.77 f5 = 15.49

Numerical Example 3
Unit mm

Surface data Surface number rd nd νd
Object ∞ ∞
1 101.325 1.80 1.88300 40.76
2 43.803 8.85 1.43875 94.93
3 -406.863 0.18
4 45.668 5.27 1.49700 81.54
5 177.307 0.18
6 52.732 4.61 1.49700 81.54
7 480.427 Variable
8 * -98.148 1.00 1.85135 40.10
9 * 11.503 6.28
10 -14.871 0.50 1.55032 75.50
11 25.421 3.03 1.92286 20.88
12 -109.248 Variable
13 (Aperture) ∞ 0.00
14 * 12.309 5.17 1.74320 49.34
15 * -111.777 0.98
16 542.713 0.50 1.60342 38.03
17 13.805 3.08
18 22.378 0.40 1.85026 32.27
19 8.636 4.75 1.49700 81.54
20 -55.400 5.96
21 14.827 2.16 1.55032 75.50
22 83.083 Variable
23 -44.755 1.67 1.80518 25.42
24 -25.242 0.40 1.74320 49.34
25 * 17.364 Variable
26 * 13.164 1.92 1.74320 49.34
27 * -58.476 0.30
28 ∞ 2.12 1.51633 64.14
29 ∞ 2.13
Imaging surface ∞

Aspheric data 8th surface
k = 0.000
A4 = 5.50918e-05, A6 = -4.23935e-08, A8 = -7.49161e-10,
A10 = 1.75420e-12
9th page
k = 0.000
A4 = 3.08495e-05, A6 = 1.21188e-07, A8 = 9.03771e-09
14th page
k = 0.000
A4 = -3.10937e-05, A6 = -1.49209e-07, A8 = -2.26123e-10,
A10 = -8.11110e-12
15th page
k = 0.000
A4 = 2.40777e-05, A6 = -6.59087e-08, A8 = 7.85749e-11,
A10 = 2.81942e-12
25th page
k = 0.000
A4 = -1.97924e-05, A6 = -2.09989e-06, A8 = 4.83988e-08
26th page
k = 0.000
A4 = 4.96161e-05, A6 = -2.64216e-06, A8 = 4.62613e-08
No. 27
k = 0.000
A4 = 1.65710e-04

Zoom data

Zoom ratio 40.00

Wide angle end Middle Telephoto end f 4.85 30.65 193.99
FNO. 1.64 3.51 4.86
2ω 75.55 12.81 2.02
IH 3.60 3.60 3.60
BF (in air) 3.82 3.82 3.82
LTL (in air) 129.28 129.28 129.28


d7 0.60 25.83 43.43
d12 58.68 19.87 2.28
d22 3.98 9.75 2.62
d25 3.50 11.31 18.44

Each group focal length
f1 = 62.35 f2 = -9.84 f3 = 21.30 f4 = -16.90 f5 = 14.62

Numerical Example 4
Unit mm

Surface data Surface number rd nd νd
Object ∞ ∞
1 117.187 2.00 1.88300 40.76
2 47.194 9.81 1.43875 94.93
3 -290.648 0.18
4 49.864 5.78 1.49700 81.54
5 214.724 0.18
6 53.848 5.65 1.49700 81.54
7 694.612 Variable
8 * -123.115 1.00 1.85135 40.10
9 * 12.032 6.58
10 -14.353 0.50 1.55032 75.50
11 26.130 3.09 1.92286 20.88
12 -117.700 Variable
13 (Aperture) ∞ 0.00
14 * 13.463 6.45 1.74320 49.34
15 * -53.683 0.85
16 -94.268 0.50 1.62035 34.19
17 16.587 3.38
18 25.839 0.40 1.85026 32.27
19 9.109 5.24 1.49700 81.54
20 -52.634 3.44
21 14.535 2.45 1.55233 50.36
22 85.956 Variable
23 -482.631 1.09 1.80518 25.42
24 -54.394 0.40 1.74320 49.34
25 * 11.821 variable
26 * 21.331 3.36 1.74320 49.34
27 * -26.322 0.30
28 ∞ 2.12 1.51633 64.14
29 ∞ 2.13
Imaging surface ∞

Aspheric data 8th surface
k = 0.000
A4 = 4.59781e-05, A6 = -6.20623e-08, A8 = -1.15639e-10,
A10 = -5.13778e-13
9th page
k = 0.000
A4 = 2.77282e-05, A6 = -1.89302e-08, A8 = 9.62194e-09
14th page
k = 0.000
A4 = -2.22589e-05, A6 = -7.98107e-08, A8 = -2.14489e-10,
A10 = -3.00000e-12
15th page
k = 0.000
A4 = 3.22935e-05, A6 = -9.15485e-08, A8 = 6.63055e-11,
A10 = 1.73518e-12
25th page
k = 0.000
A4 = -2.85879e-05, A6 = -2.25904e-06, A8 = 8.82363e-08
26th page
k = 0.000
A4 = -4.87622e-04, A6 = -1.36973e-05, A8 = -7.21269e-08
No. 27
k = 0.000
A4 = -7.08982e-04, A6 = -3.03954e-06, A8 = 1.27290e-08

Zoom data

Zoom ratio 38.00

Wide-angle end Medium telephoto end f 5.79 35.67 220.01
FNO. 1.66 3.50 4.86
2ω 74.48 12.83 2.06
IH 4.20 4.20 4.20
BF (in air) 3.82 3.82 3.82
LTL (in air) 134.28 134.28 134.28

d7 0.60 28.67 44.12
d12 57.50 19.49 2.28
d22 4.55 11.20 2.50
d25 5.47 8.76 19.23

Each group focal length
f1 = 63.49 f2 = -9.98 f3 = 20.95 f4 = -15.76 f5 = 16.35

Numerical Example 5
Unit mm

Surface data Surface number rd nd νd
Object ∞ ∞
1 107.714 2.00 1.88300 40.76
2 45.410 9.71 1.43875 94.93
3 -494.106 0.18
4 48.505 6.25 1.49700 81.54
5 259.815 0.18
6 54.366 5.47 1.49700 81.54
7 499.183 Variable
8 * -106.869 1.00 1.85135 40.10
9 * 11.595 6.40
10 -16.396 0.70 1.55032 75.50
11 25.334 3.17 1.92286 20.88
12 -115.321 Variable
13 (Aperture) ∞ 0.00
14 * 13.321 5.89 1.74320 49.34
15 * -57.484 0.97
16 -715.255 0.70 1.64858 31.26
17 16.304 4.05
18 37.404 0.40 1.85026 32.27
19 9.364 4.88 1.49700 81.54
20 -50.637 2.80
21 15.192 2.48 1.55793 46.68
22 255.364 Variable
23 -87.718 0.98 1.80518 25.42
24 -54.050 0.40 1.74320 49.34
25 * 13.768 variable
26 * 22.814 3.40 1.74320 49.34
27 * -21.477 0.30
28 ∞ 2.12 1.51633 64.14
29 ∞ 2.13
Imaging surface ∞

Aspheric data 8th surface
k = 0.000
A4 = 3.45208e-05, A6 = 6.71452e-09, A8 = -7.56622e-10,
A10 = 2.13342e-12
9th page
k = 0.000
A4 = 6.74586e-06, A6 = 1.01235e-07, A8 = 3.97278e-09
14th page
k = 0.000
A4 = -2.60000e-05, A6 = -1.00274e-07, A8 = -1.38853e-10,
A10 = -3.71310e-12
15th page
k = 0.000
A4 = 3.37463e-05, A6 = -9.15950e-08, A8 = 2.40631e-10,
A10 = 8.35367e-13
25th page
k = 0.000
A4 = -1.34821e-05, A6 = -2.70414e-06, A8 = 1.03758e-07
26th page
k = 0.000
A4 = -2.91132e-04, A6 = -1.75541e-05, A8 = 3.86548e-07,
A10 = -1.38546e-08
No. 27
k = 0.000
A4 = -3.15000e-04, A6 = -9.44000e-06, A8 = 5.38000e-08,
A10 = -1.84000e-09

Zoom data

Zoom ratio 38.00

Wide-angle end Middle Telephoto end f 5.67 34.94 215.53
FNO. 1.63 3.44 4.88
2ω 76.25 13.15 2.12
IH 4.20 4.20 4.20
BF (in air) 3.82 3.82 3.82
LTL (in air) 134.28 134.28 134.28

d7 0.60 28.47 44.02
d12 58.30 20.07 2.28
d22 5.87 11.98 2.50
d25 3.67 7.93 19.64

Each group focal length
f1 = 63.73 f2 = -10.47 f3 = 21.55 f4 = -16.03 f5 = 15.39

Numerical Example 6
Unit mm

Surface data Surface number rd nd νd
Object ∞ ∞
1 98.210 1.80 1.88300 40.76
2 43.350 9.45 1.43875 94.93
3 -573.227 0.18
4 46.134 5.41 1.49700 81.54
5 151.587 0.18
6 49.264 5.05 1.49700 81.54
7 467.153 Variable
8 * -114.661 1.00 1.85135 40.10
9 * 11.594 6.47
10 -14.155 0.50 1.55032 75.50
11 32.038 2.74 1.92286 20.88
12 -109.415 Variable
13 (Aperture) ∞ 0.00
14 * 12.924 5.28 1.74320 49.34
15 * -86.742 0.87
16 -224.609 0.50 1.60342 38.03
17 14.716 4.82
18 27.042 0.57 1.85026 32.27
19 9.600 4.29 1.49700 81.54
20 -66.027 2.70
21 16.261 2.50 1.55032 75.50
22 -107.422 Variable
23 -87.958 1.22 1.98612 16.48
24 -24.853 0.40 1.88300 40.80
25 * 40.876 Variable
26 * 23.032 0.40 1.88202 37.22
27 6.261 0.10
28 6.218 2.61 1.49700 81.61
29 -26.696 0.30
30 ∞ 2.12 1.51633 64.14
31 ∞ 2.13
Imaging surface ∞

Aspheric data 8th surface
k = 0.000
A4 = 4.29117e-05, A6 = 3.77372e-07, A8 = -4.06303e-09,
A10 = 1.04361e-11
9th page
k = 0.000
A4 = 1.12275e-05, A6 = 6.44411e-07, A8 = 9.65513e-09
14th page
k = 0.000
A4 = -2.81724e-05, A6 = -1.00042e-07, A8 = -1.71389e-10,
A10 = -6.27995e-12
15th page
k = 0.000
A4 = 2.47797e-05, A6 = -4.66770e-08, A8 = -1.89181e-10,
A10 = 2.00206e-12
25th page
k = 0.000
A4 = -4.17441e-06, A6 = 8.41651e-08, A8 = -1.05493e-08
26th page
k = 0.000
A4 = -1.03921e-04, A6 = -3.28179e-06, A8 = -2.38147e-08

Zoom data

Zoom ratio 40.00

Wide angle end Medium telephoto end f 4.93 31.16 197.22
FNO. 1.76 3.60 5.18
2ω 73.88 12.71 2.01
IH 3.60 3.60 3.60
BF (in air) 3.82 3.82 3.82
LTL (in air) 131.28 131.28 131.28

d7 0.60 27.01 43.04
d12 59.72 21.43 2.28
d22 6.58 7.45 2.50
d25 1.50 12.51 20.58

Each group focal length
f1 = 62.76 f2 = -9.30 f3 = 20.65 f4 = -34.70 f5 = -500.95

Numerical Example 7
Unit mm

Surface data Surface number rd nd νd
Object ∞ ∞
1 102.143 1.80 1.88300 40.76
2 44.111 9.51 1.43875 94.93
3 -467.797 0.18
4 46.391 5.41 1.49700 81.54
5 151.190 0.18
6 48.418 5.11 1.49700 81.54
7 417.637 Variable
8 * -111.855 1.00 1.85135 40.10
9 * 11.734 6.58
10 -14.080 0.50 1.55032 75.50
11 32.262 2.79 1.92286 20.88
12 -113.767 Variable
13 (Aperture) ∞ 0.00
14 * 12.900 5.29 1.74320 49.34
15 * -86.572 0.87
16 -183.280 0.50 1.60342 38.03
17 14.741 4.66
18 24.200 0.71 1.85026 32.27
19 9.284 4.06 1.49700 81.54
20 -81.329 3.31
21 16.066 2.38 1.55032 75.50
22 -122.544 Variable
23 -76.924 1.20 1.98612 16.48
24 -23.240 0.40 1.88300 40.80
25 * 43.268 variable
26 * 19.943 0.40 1.88202 37.22
27 6.121 2.54 1.43875 94.66
28 -17.868 0.30
29 ∞ 2.12 1.51633 64.14
30 ∞ 2.13
Imaging surface ∞

Aspheric data 8th surface
k = 0.000
A4 = 4.23956e-05, A6 = 3.84304e-07, A8 = -4.23222e-09,
A10 = 1.13823e-11
9th page
k = 0.000
A4 = 1.05403e-05, A6 = 7.59170e-07, A8 = 7.67389e-09
14th page
k = 0.000
A4 = -2.79453e-05, A6 = -9.43714e-08, A8 = -2.23776e-10,
A10 = -7.14702e-12
15th page
k = 0.000
A4 = 2.34175e-05, A6 = -3.41245e-08, A8 = -4.08755e-10,
A10 = 2.43584e-12
25th page
k = 0.000
A4 = -3.48993e-06, A6 = 1.21990e-07, A8 = -2.00781e-08
26th page
k = 0.000
A4 = -1.36064e-04, A6 = -2.42234e-06, A8 = 5.21722e-09

Zoom data

Zoom ratio 40.00

Wide angle end Middle Telephoto end f 4.91 31.05 196.55
FNO. 1.75 3.58 5.18
2ω 73.81 12.62 1.99
IH 3.60 3.60 3.60
BF (in air) 3.82 3.82 3.82
LTL (in air) 131.28 131.28 131.28

d7 0.60 27.02 42.98
d12 59.65 21.41 2.28
d22 6.43 7.34 2.50
d25 1.41 12.31 20.33

Each group focal length
f1 = 62.70 f2 = -9.27 f3 = 20.70 f4 = -34.54 f5 = -500.18

Numerical Example 8
Unit mm

Surface data Surface number rd nd νd
Object ∞ ∞
1 105.173 1.80 1.88300 40.76
2 44.394 8.51 1.43875 94.93
3 -891.218 0.18
4 49.058 5.44 1.49700 81.54
5 264.884 0.18
6 49.219 4.91 1.49700 81.54
7 456.972 Variable
8 * -123.817 1.00 1.85135 40.10
9 * 11.444 6.34
10 -14.434 0.50 1.55032 75.50
11 26.046 3.12 1.92286 20.88
12 -103.589 Variable
13 (Aperture) ∞ 0.00
14 * 12.328 5.16 1.74320 49.34
15 * -97.146 0.95
16 3208.564 0.50 1.60342 38.03
17 13.625 3.14
18 21.547 0.48 1.85026 32.27
19 8.612 6.41 1.49700 81.54
20 -65.777 6.20
21 15.165 2.23 1.55032 75.50
22 107.186 Variable
23 -44.869 1.77 1.80518 25.42
24 -27.967 0.40 1.74320 49.34
25 * 17.785 Variable
26 * 13.394 1.84 1.74320 49.34
27 * -58.321 0.30
28 ∞ 2.12 1.51633 64.14
29 ∞ 2.13
Imaging surface ∞

Aspheric data 8th surface
k = 0.000
A4 = 6.27679e-05, A6 = -4.61276e-08, A8 = -9.66567e-10,
A10 = 2.48700e-12
9th page
k = 0.000
A4 = 4.24556e-05, A6 = 1.69848e-07, A8 = 9.76631e-09
14th page
k = 0.000
A4 = -3.15220e-05, A6 = -1.43109e-07, A8 = -3.68318e-10,
A10 = -6.75502e-12
15th page
k = 0.000
A4 = 2.36012e-05, A6 = -5.52824e-08, A8 = -1.22254e-11,
A10 = 3.44260e-12
25th page
k = 0.000
A4 = -2.45195e-05, A6 = -2.37408e-06, A8 = 5.73836e-08
26th page
k = 0.000
A4 = -1.10234e-04, A6 = -5.62527e-06, A8 = 3.31973e-08
No. 27
k = 0.000
A4 = -9.31816e-05

Zoom data

Zoom ratio 40.00

Wide angle end Middle Telephoto end f 4.85 30.65 193.99
FNO. 1.64 3.47 4.94
2ω 74.16 12.83 2.02
IH 3.60 3.60 3.60
BF (in air) 3.82 3.82 3.82
LTL (in air) 131.15 131.15 131.15

d7 0.60 26.07 43.29
d12 58.98 19.85 2.28
d22 3.84 9.77 2.69
d25 2.84 10.56 18.00

Each group focal length
f1 = 62.26 f2 = -9.85 f3 = 22.19 f4 = -17.13 f5 = 14.82

Numerical Example 9
Unit mm

Surface data Surface number rd nd νd
Object ∞ ∞
1 104.214 1.80 1.88300 40.76
2 44.547 9.25 1.43875 94.93
3 -414.636 0.18
4 47.030 5.25 1.49700 81.54
5 156.823 0.18
6 48.547 4.99 1.49700 81.54
7 445.294 Variable
8 * -118.170 1.00 1.85135 40.10
9 * 11.636 6.47
10 -14.116 0.50 1.55032 75.50
11 30.605 2.80 1.92286 20.88
12 -110.143 Variable
13 (Aperture) ∞ 0.00
14 * 12.896 5.39 1.74320 49.34
15 * -95.438 0.92
16 -212.717 0.50 1.60342 38.03
17 14.985 4.45
18 23.626 0.68 1.85026 32.27
19 9.076 4.47 1.49700 81.54
20 -71.643 3.90
21 15.457 2.46 1.55032 75.50
22 -351.385 Variable
23 -72.450 1.23 1.98612 16.48
24 -23.143 0.40 1.88300 40.80
25 * 35.067 variable
26 * 26.203 0.40 1.88202 37.22
27 7.369 0.10
28 7.215 2.87 1.49700 81.61
29 -12.987 0.30
30 ∞ 2.12 1.51633 64.14
31 ∞ 2.13
Imaging surface ∞

Aspheric data 8th surface
k = 0.000
A4 = 4.06093e-05, A6 = 3.48661e-07, A8 = -3.62581e-09,
A10 = 9.09073e-12
9th page
k = 0.000
A4 = 1.15134e-05, A6 = 5.30641e-07, A8 = 9.41933e-09
14th page
k = 0.000
A4 = -2.75103e-05, A6 = -1.04390e-07, A8 = -1.83841e-10,
A10 = -6.02716e-12
15th page
k = 0.000
A4 = 2.12500e-05, A6 = -4.28396e-08, A8 = -1.33012e-10,
A10 = 1.99328e-12
25th page
k = 0.000
A4 = -4.91879e-06, A6 = -1.73227e-07, A8 = -5.68436e-09
26th page
k = 0.000
A4 = -2.19697e-04, A6 = -9.25732e-07, A8 = -2.43858e-08

Zoom data

Zoom ratio 40.00

Wide angle end Middle Telephoto end f 4.85 30.68 194.17
FNO. 1.71 3.61 5.02
2ω 74.31 12.82 2.03
IH 3.60 3.60 3.60
BF (in air) 3.82 3.82 3.82
LTL (in air) 131.28 131.28 131.28

d7 0.60 26.05 43.08
d12 59.33 20.63 2.28
d22 5.54 7.72 2.51
d25 1.80 12.87 19.39

Each group focal length
f1 = 62.43 f2 = -9.40 f3 = 21.08 f4 = -28.94 f5 = 42.90

Numerical Example 10
Unit mm

Surface data Surface number rd nd νd
Object ∞ ∞
1 98.580 1.80 1.88300 40.76
2 43.657 8.82 1.43875 94.93
3 -1513.058 0.18
4 55.615 4.30 1.49700 81.54
5 162.451 0.18
6 39.783 6.25 1.49700 81.54
7 347.137 Variable
8 * -208.836 1.00 1.85135 40.10
9 * 10.739 6.74
10 -14.585 0.50 1.55032 75.50
11 28.504 3.00 1.92286 20.88
12 -101.724 Variable
13 (Aperture) ∞ 0.00
14 * 13.116 6.82 1.74320 49.34
15 * -75.210 0.77
16 -155.372 0.50 1.60342 38.03
17 16.058 3.22
18 24.604 0.40 1.85026 32.27
19 8.771 6.15 1.49700 81.54
20 -87.779 4.78
21 18.216 2.86 1.55032 75.50
22 * -75.122 variable
23 -45.171 1.06 1.98612 16.48
24 -27.342 0.40 1.88300 40.80
25 * 57.494 variable
26 ∞ 2.12 1.51633 64.14
27 ∞ 2.13
Imaging surface ∞

Aspheric data 8th surface
k = 0.000
A4 = 6.37420e-05, A6 = -4.91662e-08, A8 = -1.90651e-09,
A10 = 6.80358e-12
9th page
k = 0.000
A4 = 3.12247e-05, A6 = 7.10193e-07, A8 = 1.52586e-09
14th page
k = 0.000
A4 = -2.60762e-05, A6 = -6.66582e-08, A8 = -2.54822e-10,
A10 = -3.43689e-12
15th page
k = 0.000
A4 = 2.82972e-05, A6 = -6.66924e-09, A8 = -4.61191e-10,
A10 = 3.38898e-12
22nd page
k = 0.000
A4 = -3.54888e-06, A6 = -2.24783e-07, A8 = 5.93566e-09
25th page
k = 0.000
A4 = -2.29067e-05, A6 = 2.13802e-06, A8 = -1.02251e-07

Zoom data

Zoom ratio 40.00

Wide-angle end Medium Telephoto end f 5.10 32.23 204.00
FNO. 1.77 3.70 5.34
2ω 74.31 12.81 2.02
IH 3.60 3.60 3.60
BF (in air) 5.24 15.67 23.81
LTL (in air) 131.28 131.28 131.28

d7 0.60 26.47 42.97
d12 58.86 20.40 2.28
d22 6.86 9.01 2.50
d25 1.71 12.15 20.28

Each group focal length
f1 = 62.59 f2 = -9.51 f3 = 22.34 f4 = -29.75

Numerical Example 11
Unit mm

Surface data Surface number rd nd νd
Object ∞ ∞
1 101.325 1.80 1.88300 40.76
2 43.803 8.85 1.43875 94.93
3 -406.863 0.18
4 45.668 5.27 1.49700 81.54
5 177.307 0.18
6 52.732 4.61 1.49700 81.54
7 480.427 Variable
8 * -98.148 1.00 1.85135 40.10
9 * 11.503 6.28
10 -14.871 0.50 1.55032 75.50
11 25.421 3.03 1.92286 20.88
12 -109.248 Variable
13 (Aperture) ∞ 0.00
14 * 12.309 5.17 1.74320 49.34
15 * -111.777 0.98
16 542.713 0.50 1.60342 38.03
17 13.805 3.08
18 22.378 0.40 1.85026 32.27
19 8.636 4.75 1.49700 81.54
20 -55.400 5.96
21 14.827 2.16 1.55032 75.50
22 83.083 Variable
23 -44.755 1.67 1.80518 25.42
24 -25.242 0.40 1.74320 49.34
25 * 17.364 Variable
26 * 13.164 1.92 1.74320 49.34
27 * -58.476 0.30
28 ∞ 2.12 1.51633 64.14
29 ∞ 2.13
Imaging surface ∞

Aspheric data 8th surface
k = 0.000
A4 = 5.50918e-05, A6 = -4.23935e-08, A8 = -7.49161e-10,
A10 = 1.75420e-12
9th page
k = 0.000
A4 = 3.08495e-05, A6 = 1.21188e-07, A8 = 9.03771e-09
14th page
k = 0.000
A4 = -3.10937e-05, A6 = -1.49209e-07, A8 = -2.26123e-10,
A10 = -8.11110e-12
15th page
k = 0.000
A4 = 2.40777e-05, A6 = -6.59087e-08, A8 = 7.85749e-11,
A10 = 2.81942e-12
25th page
k = 0.000
A4 = -1.97924e-05, A6 = -2.09989e-06, A8 = 4.83988e-08
26th page
k = 0.000
A4 = 4.96161e-05, A6 = -2.64216e-06, A8 = 4.62613e-08
No. 27
k = 0.000
A4 = 1.65710e-04

Zoom data

Zoom ratio 41.30

Wide-angle end Medium Telephoto end f 4.85 30.65 200.31
FNO. 1.64 3.51 4.96
2ω 75.55 12.81 1.95
IH 3.60 3.60 3.60
BF (in air) 3.82 3.82 3.83
LTL (in air) 129.28 129.28 129.49

d7 0.60 25.83 43.63
d12 58.68 19.87 2.28
d22 3.98 9.75 1.83
d25 3.50 11.31 19.23

Each group focal length
f1 = 62.35 f2 = -9.84 f3 = 21.30 f4 = -16.90 f5 = 14.62

Next, the values of the conditional expressions in each example are listed below. -(Hyphen) indicates no corresponding configuration.

Conditional Example Example 1 Example 2 Example 3 Example 4
(1) Δ1G / Δ2G 0.000 0.000 0.000 0.000
(2) dG3L12 / dG3 0.172 0.170 0.259 0.151
(3) | fG3L2 / fG3 | 2.118 2.151 1.523 1.493
(4) | fG3Lo / fG3 | 0.899 0.906 0.713 0.721
(5) SFG3L2 -2.625 -2.682 -1.434 -1.407
(6) | (1-βG3L2w)
× βbackw | 0.416 0.419 0.453 0.600
(7) | (1-βG3L2t)
× βbackt | 0.647 0.638 0.811 0.923
(8) fG3 / fw 2.784 2.773 4.391 3.618
(9) fG3 / ft 0.127 0.121 0.110 0.095
(10) β2Gt / β2Gw 12.51 13.49 19.69 23.47
(11) dG3L12 / fG3L2 0.0962 0.0949 0.1838 0.1099
(12) νd1Gn 24.8 24.8 40.76 40.76
(13) θg, F1Gn 0.612 0.612 0.567 0.567
(14) ft / fw 22.00 23.00 40.00 38.00

Conditional Example Example 5 Example 6 Example 7 Example 8
(1) Δ1G / Δ2G 0.000 0.000 0.000 0.000
(2) dG3L12 / dG3 0.126 0.125 0.152 0.247
(3) | fG3L2 / fG3 | 1.338 1.252 1.254 1.434
(4) | fG3Lo / fG3 | 0.700 0.750 0.747 0.677
(5) SFG3L2 -1.127 -0.737 -0.768 -1.330
(6) | (1-βG3L2w)
× βbackw | 0.622 0.713 0.692 0.601
(7) | (1-βG3L2t)
× βbackt | 0.978 1.385 1.360 0.822
(8) fG3 / fw 3.800 4.188 4.214 4.575
(9) fG3 / ft 0.100 0.105 0.105 0.114
(10) β2Gt / β2Gw 24.16 15.44 15.32 18.82
(11) dG3L12 / fG3L2 0.0971 0.1046 0.1273 0.1947
(12) νd1Gn 40.76 40.76 40.76 40.76
(13) θg, F1Gn 0.567 0.567 0.567 0.567
(14) ft / fw 38.00 40.00 40.00 40.00

Conditional Example Example 9 Example 10 Example 11
(1) Δ1G / Δ2G 0.000 0.000 -0.005
(2) dG3L12 / dG3 0.171 0.187 0.259
(3) | fG3L2 / fG3 | 1.279 1.206 1.523
(4) | fG3Lo / fG3 | 0.741 0.696 0.713
(5) SFG3L2 -0.916 -0.610 -1.434
(6) | (1-βG3L2w)
× βbackw | 0.627 0.594 0.453
(7) | (1-βG3L2t)
× βbackt | 1.204 1.190 0.790
(8) fG3 / fw 4.342 4.380 4.391
(9) fG3 / ft 0.109 0.110 0.106
(10) β2Gt / β2Gw 16.47 16.58 21.57
(11) dG3L12 / fG3L2 0.1445 0.1775 0.1838
(12) νd1Gn 40.76 40.76 40.76
(13) θg, F1Gn 0.567 0.567 0.567
(14) ft / fw 40.00 40.00 41.30

  FIG. 23 is a cross-sectional view of a single-lens mirrorless camera as an imaging apparatus. In FIG. 23, a photographing optical system 2 is disposed in the lens barrel of the single-lens mirrorless camera 1. The mount unit 3 allows the photographing optical system 2 to be attached to and detached from the body of the single lens mirrorless camera 1. As the mount unit 3, a screw type mount, a bayonet type mount, or the like is used. In this example, a bayonet type mount is used. An imaging element surface 4 and a back monitor 5 are disposed on the body of the single lens mirrorless camera 1. A small CCD or CMOS is used as the image sensor.

  As the photographing optical system 2 of the single lens mirrorless camera 1, for example, the variable magnification optical system shown in the above embodiment is used.

  24 and 25 are conceptual diagrams of the configuration of the imaging apparatus. FIG. 24 is a front perspective view of a digital camera 40 as an imaging apparatus, and FIG. 25 is a rear perspective view of the same. The variable magnification optical system of the present embodiment is used for the photographing optical system 41 of the digital camera 40.

  The digital camera 40 of this embodiment includes 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, In conjunction with this, photographing is performed through the photographing optical system 41, for example, the variable magnification optical system of the first embodiment. An object image formed by the photographing optical system 41 is formed on an image sensor (photoelectric conversion surface) provided in the vicinity of the imaging surface. The object image received by the image sensor is displayed on the liquid crystal display monitor 47 provided on the back of the camera as an electronic image by the processing means. The taken electronic image can be recorded in the storage means.

  FIG. 26 is a block diagram showing an internal circuit of a main part of the digital camera 40. In the following description, the processing means described above is configured by, for example, the CDS / ADC unit 24, the temporary storage memory 17, the image processing unit 18, and the like, and the storage unit is configured by the storage medium unit 19 or the like.

  As shown in FIG. 26, the digital camera 40 is connected to the operation unit 12, the control unit 13 connected to the operation unit 12, and the control signal output port of the control unit 13 via buses 14 and 15. An imaging drive circuit 16, a temporary storage memory 17, an image processing unit 18, a storage medium unit 19, a display unit 20, and a setting information storage memory unit 21 are provided.

  The temporary storage memory 17, the image processing unit 18, the storage medium unit 19, the display unit 20, and the setting information storage memory unit 21 can mutually input and output data via the bus 22. In addition, a CCD 49 and a CDS / ADC unit 24 are connected to the imaging drive circuit 16.

  The operation unit 12 includes various input buttons and switches, and notifies the control unit 13 of event information input from the outside (camera user) via these buttons. 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 controls the entire digital camera 40 according to a program stored in the program memory.

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

  The CDS / ADC unit 24 amplifies the electrical signal input from the CCD 49 and performs analog / digital conversion, and raw video data (Bayer data, hereinafter referred to as RAW data) obtained by performing the amplification and digital conversion. Is output to the temporary storage memory 17.

  The temporary storage memory 17 is a buffer made of, for example, SDRAM, and is a memory device that temporarily stores RAW data output from the CDS / ADC unit 24. The image processing unit 18 reads out the RAW data stored in the temporary storage memory 17 or the RAW data stored in the storage medium unit 19, and includes distortion correction based on the image quality parameter designated by the control unit 13. It is a circuit that performs various image processing electrically.

  The storage medium unit 19 is detachably mounted with a card-type or stick-type recording medium made of, for example, a flash memory, and the RAW data transferred from the temporary storage memory 17 or the image processing unit 18 to these flash memories. Image-processed image data is recorded and held.

  The display unit 20 includes a liquid crystal display monitor 47 and the like, and displays captured RAW data, image data, an operation menu, and the like. The setting information storage memory unit 21 includes 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 operation unit 12.

  The variable magnification optical system of the present embodiment can be used for surveillance cameras and endoscopes. The imaging device is not limited to the single lens mirrorless camera described above. A surveillance camera and an endoscope are also included in the imaging apparatus of the present embodiment.

  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 does not substantially have a refractive power may be disposed in each lens group or outside each lens group.

  As described above, the present invention is suitable for a variable magnification optical system having a high imaging performance even during blur correction and an image pickup apparatus including the same while the entire length of the optical system is short and compact.

G1 1st lens group G2 2nd lens group G3 3rd lens group G4 4th lens group G5 5th lens group S Aperture stop I Imaging surface 1 Single-lens mirrorless camera 2 Imaging optical system 3 Mount part 4 Imaging element surface 5 Back monitor DESCRIPTION OF SYMBOLS 12 Operation part 13 Control part 14, 15 Bus 16 Imaging drive circuit 17 Temporary storage memory 18 Image processing part 19 Storage medium part 20 Display part 21 Setting information storage memory part 22 Bus 24 CDS / ADC part 40 Digital camera 41 Shooting optical system 42 Optical path for shooting 45 Shutter button 47 LCD monitor 49 CCD

Claims (16)

From the object side,
A first lens group having a positive refractive power;
A second lens group having negative refractive power;
A third lens group having positive refractive power;
A fourth lens group having negative refractive power,
At the time of zooming, the second lens group and the fourth lens group move in the optical axis direction,
The third lens group includes a first lens element and a second lens element,
The first lens element is located next to the second lens element;
The second lens element is located closest to the image side,
Blur is corrected by moving only the second lens element in a direction perpendicular to the optical axis,
A variable magnification optical system characterized by satisfying the following conditional expressions (1) and (2).
-0.05 <Δ1G / Δ2G <0.05 (1)
0.10 <dG3L12 / dG3 <0.35 (2)
here,
Δ1G is the amount of movement of the first lens group from the wide-angle end to the telephoto end,
Δ2G is the amount of movement of the second lens group from the wide-angle end to the telephoto end,
dG3L12 is an air gap between the first lens element and the second lens element;
dG3 is the thickness of the third lens group,
It is. The second lens element is a positive lens;
The zoom lens system according to claim 1, wherein the following conditional expression (3) is satisfied.
0.800 <| fG3L2 / fG3 | <2.500 (3)
here,
fG3L2 is the focal length of the second lens element,
fG3 is the focal length of the third lens group,
It is. The third lens group has an object-side positive lens closest to the object side,
The zoom lens system according to claim 1, wherein the following conditional expression (4) is satisfied.
0.400 <| fG3Lo / fG3 | <1.200 (4)
here,
fG3Lo is the focal length of the object side positive lens,
fG3 is the focal length of the third lens group,
It is. The second lens element is a positive lens;
The zoom lens system according to claim 1, wherein the following conditional expression (5) is satisfied.
-4 <SFG3L2 <-0.25 (5)
here,
SFG3L2 = (RG3L2o + RG3L2i) / (RG3L2o−RG3L2i),
RG3L2o is the radius of curvature of the object side surface of the second lens element,
RG3L2i is the radius of curvature of the image side surface of the second lens element,
It is. The zoom lens system according to claim 1, wherein the following conditional expressions (6) and (7) are satisfied.
0.300 <| (1-βG3L2w) × βbackw | <1.000 (6)
0.500 <| (1-βG3L2t) × βbackt | <2.000 (7)
here,
βG3L2w is the lateral magnification of the second lens element at the wide-angle end,
βG3L2t is the lateral magnification of the second lens element at the telephoto end,
βbackw is the lateral magnification of a predetermined lens group at the wide-angle end,
βbackt is the lateral magnification of a predetermined lens group at the telephoto end,
The lateral magnification is the lateral magnification when focusing on an object point at infinity,
The predetermined lens group is a lens group including all lenses positioned on the image side of the third lens group,
It is.   The variable magnification optical system according to claim 1, wherein the third lens group includes one positive lens element and at least one negative lens element. An aperture stop that limits the axial luminous flux;
2. The variable magnification optical system according to claim 1, wherein the aperture stop is positioned between an image side surface of the second lens group and the third lens group. The zoom lens system according to claim 1, wherein the following conditional expression (8) is satisfied.
2.00 <fG3 / fw <5.50 (8)
here,
fG3 is the focal length of the third lens group,
fw is the focal length of the variable magnification optical system at the wide-angle end,
It is. The zoom lens system according to claim 1, wherein the following conditional expression (9) is satisfied.
0.070 <fG3 / ft <0.170 (9)
here,
fG3 is the focal length of the third lens group,
ft is the focal length of the zoom optical system at the telephoto end,
It is. The zoom lens system according to claim 1, wherein the following conditional expression (10) is satisfied.
10 <β2Gt / β2Gw <40 (10)
here,
β2Gt is the lateral magnification of the second lens group at the telephoto end,
β2Gw is the lateral magnification of the second lens group at the wide-angle end,
The magnification is the magnification at the time of focusing on an object point at infinity,
It is. The zoom lens system according to claim 1, wherein the following conditional expression (11) is satisfied.
0.040 <dG3L12 / fG3L2 <0.400 (11)
here,
dG3L12 is an air gap between the first lens element and the second lens element;
fG3L2 is the focal length of the second lens element,
It is. 2. The variable magnification optical system according to claim 1, wherein the first lens group includes at least one negative lens that satisfies the following conditional expressions (12) and (13).
24 <νd1Gn <56 (12)
0.53 <θg, F1Gn <0.62 (13)
here,
νd1Gn is the maximum Abbe number among the Abbe numbers of the negative lenses included in the first lens group,
θg, F1Gn is the minimum partial dispersion ratio among the partial dispersion ratios of the negative lens included in the first lens group,
The partial dispersion ratio is expressed by θg, F1Gn = (ng1Gn−nF1Gn) / (nF1Gn−nC1Gn),
ng1Gn, nF1Gn, and nC1Gn are the refractive index for g-line, the refractive index for F-line, the refractive index for C-line,
It is.   2. The variable magnification optical system according to claim 1, wherein only the fourth lens group moves toward the image side when focusing from an infinite object point to a close object point.   2. The variable magnification optical system according to claim 1, wherein the first lens group is fixed at the time of zooming. The zoom lens system according to claim 1, wherein the following conditional expression (14) is satisfied.
19 <ft / fw <50 (14)
here,
ft is the focal length of the zoom optical system at the telephoto end,
fw is the focal length of the variable magnification optical system at the wide-angle end,
It is. Optical system,
An imaging device having an imaging surface and converting an image formed on the imaging surface by the optical system into an electrical signal;
An imaging apparatus, wherein the optical system is the variable magnification optical system according to claim 1.

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