JP2017156428A - Variable power optical system, optical apparatus and method for manufacturing variable power optical system - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a variable power optical system that is small and has good optical performance, an optical apparatus and a method for manufacturing a variable power optical system.SOLUTION: The variable power optical system includes, successively from an object side, a first lens group G1 having a positive refractive power, a second lens group G2 having a negative refractive power, a third lens group G3 having a positive refractive power, a fourth lens group G4 having a negative refractive power, and a fifth lens group G5 having a positive refractive power, in which upon varying powers from a wide angle end state to a telephoto end state, intervals among the lens groups vary; and upon focusing, the fourth lens group G4 moves along the optical axis. The first lens group G1 is constituted by a single lens component.SELECTED DRAWING: Figure 1

Description

  The present invention relates to a variable magnification optical system, an optical apparatus, and a method for manufacturing the variable magnification optical system.

  Conventionally, a variable magnification optical system suitable for a photographic camera, an electronic still camera, a video camera, and the like has been proposed (see, for example, Patent Document 1). However, Patent Document 1 has a problem that further improvement in optical performance is desired.

JP 2006-113572 A

  The variable magnification optical system according to the first aspect of the present invention has, in order from the object side, a first lens group having a positive refractive power, a second lens group having a negative refractive power, and a positive refractive power. A first lens having a third lens group, a fourth lens group having a negative refractive power, and a fifth lens group having a positive refractive power, during zooming from the wide-angle end state to the telephoto end state; The distance between the second lens group and the second lens group is changed, the distance between the second lens group and the third lens group is changed, the distance between the third lens group and the fourth lens group is changed, and The distance from the fifth lens group changes, and at the time of focusing, the fourth lens group moves along the optical axis, and the first lens group is composed of one lens component.

  The variable magnification optical system manufacturing method according to the first aspect of the present invention 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 positive lens group. And a fourth lens group having negative refracting power, and a fifth lens group having positive refracting power. At the time of zooming from the state to the telephoto end state, the distance between the first lens group and the second lens group changes, the distance between the second lens group and the third lens group changes, and the third lens group and the fourth lens group change. The distance between the lens group is changed and the distance between the fourth lens group and the fifth lens group is changed, and the fourth lens group is arranged to move along the optical axis at the time of focusing, One lens component is arranged as the first lens group.

It is sectional drawing which shows the lens structure of the variable magnification optical system which concerns on 1st Example. FIG. 5A is a diagram illustrating various aberrations in the wide-angle end state of the variable magnification optical system according to the first example, where FIG. 9A is a diagram illustrating various aberrations when in the infinite focus state, and FIG. FIG. 10 is a lateral aberration diagram when camera shake correction is performed. FIG. 4A is a diagram illustrating various aberrations in the intermediate focal length state of the variable magnification optical system according to the first example, where FIG. 5A is a diagram illustrating various aberrations when the zoom lens is in the infinite focus state, and FIG. FIG. 6 is a lateral aberration diagram when camera shake correction is performed in FIG. FIG. 5A is a diagram illustrating various aberrations in the telephoto end state of the variable magnification optical system according to the first example, where FIG. 9A is a diagram illustrating various aberrations in the infinite focus state, and FIG. FIG. 10 is a lateral aberration diagram when camera shake correction is performed. FIG. 5A is a diagram illustrating various aberrations of the zoom optical system according to the first example in a close-up focus state, where FIG. 9A is a diagram illustrating various aberrations when the zoom lens is in the wide-angle end state, and FIG. FIG. 4C is a diagram illustrating various aberrations in the telephoto end state. It is sectional drawing which shows the lens structure of the variable magnification optical system which concerns on 2nd Example. FIG. 6A is a diagram illustrating various aberrations in the wide-angle end state of the variable magnification optical system according to the second example, where FIG. 9A is a diagram illustrating all aberrations in the infinite focus state, and FIG. FIG. 10 is a lateral aberration diagram when camera shake correction is performed. FIG. 7A is a diagram illustrating various aberrations in the intermediate focal length state of the variable magnification optical system according to the second example, where FIG. 9A is a diagram illustrating various aberrations when in the infinite focus state, and FIG. FIG. 6 is a lateral aberration diagram when camera shake correction is performed in FIG. FIG. 6A is a diagram illustrating various aberrations in the telephoto end state of the variable magnification optical system according to the second example, where FIG. 9A is a diagram illustrating various aberrations when in the infinite focus state, and FIG. FIG. 10 is a lateral aberration diagram when camera shake correction is performed. FIG. 9A is a diagram illustrating various aberrations of the zoom optical system according to Example 2 in a close-up focus state, where FIG. 9A is a diagram illustrating all aberrations when the zoom lens is in the wide-angle end state, and FIG. FIG. 4C is a diagram illustrating various aberrations in the telephoto end state. It is sectional drawing which shows the lens structure of the variable magnification optical system which concerns on 3rd Example. FIG. 7A is a diagram illustrating various aberrations in the wide-angle end state of the variable magnification optical system according to the third example, where FIG. 9A is a diagram illustrating various aberrations when in the infinite focus state, and FIG. FIG. 10 is a lateral aberration diagram when camera shake correction is performed. FIG. 6A is a diagram illustrating various aberrations in the intermediate focal length state of the variable magnification optical system according to the third example, where FIG. 9A is a diagram illustrating various aberrations when in the infinite focus state, and FIG. FIG. 6 is a lateral aberration diagram when camera shake correction is performed in FIG. FIG. 7A is a diagram illustrating various aberrations in the telephoto end state of the variable magnification optical system according to the third example, where FIG. 9A is a diagram illustrating various aberrations when in the infinite focus state, and FIG. FIG. 10 is a lateral aberration diagram when camera shake correction is performed. FIG. 9A is a diagram illustrating various aberrations of the zoom optical system according to Example 3 in a close-up focus state, where FIG. 9A is a diagram illustrating various aberrations when in the wide-angle end state, and FIG. FIG. 4C is a diagram illustrating various aberrations in the telephoto end state. It is sectional drawing which shows the lens structure of the variable magnification optical system which concerns on 4th Example. FIG. 6A is a diagram illustrating various aberrations in the wide-angle end state of the variable magnification optical system according to the fourth example, where FIG. 9A is a diagram illustrating all aberrations in the infinite focus state, and FIG. FIG. 10 is a lateral aberration diagram when camera shake correction is performed. FIG. 7A is a diagram illustrating various aberrations in the intermediate focal length state of the variable magnification optical system according to the fourth example, where FIG. 9A is a diagram illustrating various aberrations in the infinite focus state, and FIG. FIG. 6 is a lateral aberration diagram when camera shake correction is performed in FIG. FIG. 7A is a diagram illustrating various aberrations in the telephoto end state of the variable magnification optical system according to the fourth example, where FIG. 9A is a diagram illustrating various aberrations when in the infinite focus state, and FIG. FIG. 10 is a lateral aberration diagram when camera shake correction is performed. FIG. 9A is a diagram illustrating various aberrations of the zoom optical system according to Example 4 in a close-up focus state, where FIG. 9A is a diagram illustrating various aberrations when in the wide-angle end state, and FIG. FIG. 4C is a diagram illustrating various aberrations in the telephoto end state. It is sectional drawing which shows the lens structure of the variable magnification optical system which concerns on 5th Example. FIG. 6A is a diagram illustrating various aberrations in the wide-angle end state of the variable magnification optical system according to Example 5; FIG. 9A is a diagram illustrating all aberrations in the infinite focus state, and FIG. FIG. 10 is a lateral aberration diagram when camera shake correction is performed. FIG. 9A is a diagram illustrating various aberrations in the intermediate focal length state of the variable magnification optical system according to the fifth example, where FIG. 9A is a diagram illustrating various aberrations when in the infinite focus state, and FIG. FIG. 6 is a lateral aberration diagram when camera shake correction is performed in FIG. FIG. 7A is a diagram illustrating various aberrations of the zoom optical system according to Example 5 in the telephoto end state, where FIG. 9A is a diagram illustrating various aberrations in the infinite focus state, and FIG. FIG. 10 is a lateral aberration diagram when camera shake correction is performed. FIG. 9A is a diagram illustrating various aberrations of the variable magnification optical system according to Example 5 in the close-up focus state, where FIG. 9A is a diagram illustrating aberrations at the wide-angle end state, and FIG. FIG. 4C is a diagram illustrating various aberrations in the telephoto end state. It is sectional drawing which shows the lens structure of the variable magnification optical system which concerns on 6th Example. FIG. 6A is a diagram illustrating various aberrations of the variable magnification optical system according to Example 6 in the wide-angle end state, where FIG. 9A is a diagram illustrating various aberrations when in the infinite focus state, and FIG. FIG. 10 is a lateral aberration diagram when camera shake correction is performed. FIG. 9A is a diagram illustrating various aberrations in the intermediate focal length state of the variable magnification optical system according to the sixth example, where FIG. 9A is a diagram illustrating various aberrations when in the infinite focus state, and FIG. FIG. 6 is a lateral aberration diagram when camera shake correction is performed in FIG. FIG. 9A is a diagram illustrating various aberrations of the zoom optical system according to Example 6 in the telephoto end state, where FIG. 9A is a diagram illustrating aberrations in the infinite focus state, and FIG. FIG. 10 is a lateral aberration diagram when camera shake correction is performed. FIG. 9A is a diagram illustrating various aberrations of the zoom optical system according to Example 6 in a close-up focus state, where FIG. 9A is a diagram illustrating aberrations at the wide-angle end state, and FIG. FIG. 4C is a diagram illustrating various aberrations in the telephoto end state. It is sectional drawing of the camera carrying the said variable magnification optical system. It is a flowchart for demonstrating the manufacturing method of the said variable magnification optical system.

  Hereinafter, preferred embodiments will be described with reference to the drawings. As shown in FIG. 1, the variable magnification optical system ZL according to the present embodiment includes, in order from the object side, a first lens group G1 having a positive refractive power, a second lens group G2 having a negative refractive power, A third lens group G3 having a positive refractive power, a fourth lens group G4 having a negative refractive power, and a fifth lens group G5 having a positive refractive power, and from the wide-angle end state to the telephoto end state At the time of zooming, the distance between the first lens group G1 and the second lens group G2 changes, the distance between the second lens group G2 and the third lens group G3 changes, and the third lens group G3 and the fourth lens group G4 change. The distance between the lens group G4 changes and the distance between the fourth lens group G4 and the fifth lens group G5 changes. As described above, the variable magnification optical system ZL according to the present embodiment has a positive, negative, positive, and negative five-group configuration, and the distance between the lens groups changes at the time of zooming, so that small and good optical performance can be obtained. .

  The variable magnification optical system ZL according to the present embodiment is configured such that the fourth lens group G4 moves along the optical axis during focusing. In this way, by focusing with the fourth lens group G4, it is possible to suppress changes in image magnification, spherical aberration, and astigmatism fluctuations during focusing.

  In the zoom optical system ZL according to the present embodiment, it is desirable that the first lens group G1 is composed of one lens component. With this configuration, a small and good optical performance can be obtained.

  In the zoom optical system ZL according to the present embodiment, it is desirable that the fifth lens group G5 is fixed with respect to the image plane I during zooming. Since the fifth lens group G5 is fixed with respect to the image plane I at the time of zooming, the mechanism for moving the lens group can be simplified, and a compact zooming optical system ZL can be achieved. In addition, manufacturing error sensitivity (astigmatism fluctuation) can be reduced.

  In the zoom optical system ZL according to the present embodiment, it is desirable that the first lens group G1 includes a lens that satisfies the following conditional expression (1).

40.000 <νd1 (1)
However,
νd1: Abbe number with respect to the d-line of the medium of the lens constituting the first lens group G1

  Conditional expression (1) defines the Abbe number of the first lens group G1. By disposing a lens that satisfies the conditional expression (1) in the first lens group G1, fluctuations in axial chromatic aberration and lateral chromatic aberration that occur during zooming can be suppressed. In order to secure the effect of the conditional expression (1), it is desirable to set the lower limit value of the conditional expression (1) to 50.000. In order to further secure the effect of conditional expression (1), it is desirable to set the lower limit of conditional expression (1) to 60.000.

  In addition, it is desirable that the variable magnification optical system ZL according to the present embodiment satisfies the following conditional expression (2).

2.000 <f1 / (d12t-d12w) <8.00 (3)
However,
d12t: Distance between the first lens group G1 and the second lens group G2 in the telephoto end state d12w: Distance between the first lens group G1 and the second lens group G2 in the wide-angle end state f1: Focal length of the first lens group G1

  Conditional expression (2) defines the focal length of the first lens group G1 with respect to the amount of change in the distance between the first lens group G1 and the second lens group G2 from the wide-angle end state to the telephoto end state. Exceeding the upper limit value of conditional expression (2) is not preferable because when the amount of movement of the first lens group G1 becomes small, fluctuations in spherical aberration during zooming cannot be suppressed. In order to secure the effect of conditional expression (2), it is desirable to set the upper limit of conditional expression (2) to 7.600. In order to further secure the effect of conditional expression (2), it is desirable to set the upper limit value of conditional expression (2) to 7.300. On the other hand, if the lower limit of conditional expression (2) is not reached, the focal length of the first lens group G1 becomes small, which makes it difficult to correct chromatic aberration, which is not preferable. In order to secure the effect of conditional expression (2), it is desirable to set the lower limit value of conditional expression (2) to 2.200. In order to further secure the effect of the conditional expression (2), it is desirable to set the lower limit value of the conditional expression (2) to 2.400.

  In addition, it is desirable that the variable magnification optical system ZL according to the present embodiment satisfies the following conditional expression (3).

0.120 <(d12t-d12w) ² / Σ (dit-diw) ² <0.900 (3)
However,
d12t: Distance between the first lens group G1 and the second lens group G2 in the telephoto end state d12w: Distance between the first lens group G1 and the second lens group G2 in the wide-angle end state Σ (dit-diw) ² : Wide-angle end Sum of squares of the amount of change between each lens group when zooming from the lens to the telephoto end

  Conditional expression (3) is the amount of change from the wide-angle end state to the telephoto end state of the group interval between the first lens group G1 and the second lens group G2 with respect to the amount of change from the wide-angle end state to the telephoto end state of each group interval. The relationship is defined. Exceeding the upper limit of conditional expression (3) is not preferable because it becomes difficult to correct chromatic aberration when the amount of movement of the first lens group G1 increases. In order to secure the effect of conditional expression (3), it is desirable to set the upper limit value of conditional expression (3) to 0.800. In order to further secure the effect of conditional expression (3), it is desirable to set the upper limit value of conditional expression (3) to 0.700. On the other hand, if the lower limit of conditional expression (3) is not reached, it is not preferable because the variation of spherical aberration during zooming cannot be suppressed when the amount of movement of the first lens group G1 becomes small. In order to secure the effect of conditional expression (3), it is desirable to set the lower limit value of conditional expression (3) to 0.140. In order to further secure the effect of conditional expression (3), it is desirable to set the lower limit of conditional expression (3) to 0.150.

  In addition, it is desirable that the variable magnification optical system ZL according to the present embodiment satisfies the following conditional expression (4).

0.800 <f5 / f1 <4.100 (4)
However,
f5: focal length of the fifth lens group G5 f1: focal length of the first lens group G1

  Conditional expression (4) defines the focal length of the first lens group G1 with respect to the focal length of the fifth lens group G5. Exceeding the upper limit of conditional expression (4) is not preferable because the focal length of the first lens group G1 becomes small and correction of chromatic aberration becomes difficult. In order to secure the effect of conditional expression (4), it is desirable to set the upper limit of conditional expression (4) to 3.750. In order to further secure the effect of the conditional expression (4), it is desirable to set the upper limit of the conditional expression (4) to 3.400. If the lower limit value of conditional expression (4) is not reached, the focal length of the first lens group G1 increases and the total length in the telephoto end state increases, making it impossible to realize a compact optical system. Further, it is not preferable because fluctuations in spherical aberration and astigmatism during zooming cannot be suppressed. In order to secure the effect of conditional expression (4), it is desirable to set the lower limit of conditional expression (4) to 1.000. In order to further secure the effect of conditional expression (4), it is desirable to set the lower limit of conditional expression (4) to 1.400.

  In addition, it is desirable that the variable magnification optical system ZL according to the present embodiment satisfies the following conditional expression (5).

0.400 <(-f4) / f1 <3.0000 (5)
However,
f4: focal length of the fourth lens group G4 f1: focal length of the first lens group G1

  Conditional expression (5) defines the focal length of the first lens group G1 with respect to the focal length of the fourth lens group G4 which is a focusing lens group. Exceeding the upper limit value of conditional expression (5) is not preferable because fluctuations in spherical aberration and astigmatism during focusing cannot be suppressed. In order to secure the effect of conditional expression (5), it is desirable to set the upper limit value of conditional expression (5) to 2.500. In order to further secure the effect of the conditional expression (5), it is desirable to set the upper limit value of the conditional expression (5) to 2.200. On the other hand, if the lower limit of conditional expression (5) is not reached, the refractive power of the fourth lens group G4 becomes too weak, and the amount of movement during focusing increases. In this case, it is not preferable because fluctuations in spherical aberration and astigmatism during focusing cannot be suppressed. In order to secure the effect of conditional expression (5), it is desirable to set the lower limit value of conditional expression (5) to 0.500. In order to further secure the effect of the conditional expression (5), it is desirable to set the lower limit value of the conditional expression (5) to 0.700.

  In the variable magnification optical system ZL according to the present embodiment, it is desirable that the fifth lens group G5 is composed of a single lens. With this configuration, the configuration of the variable magnification optical system ZL is simplified, and a compact lens can be realized.

  In the zoom optical system ZL according to this embodiment, it is desirable that the fifth lens group G5 includes a lens that satisfies the following conditional expression (6).

νd5 ≦ 35.000 (6)
However,
νd5: Abbe number with respect to the d-line of the medium of the lens constituting the fifth lens group G5

  Conditional expression (6) defines the Abbe number of the fifth lens group G5. Exceeding the upper limit value of the conditional expression (6) is not preferable because a change in lateral chromatic aberration during zooming cannot be suppressed. In order to secure the effect of conditional expression (6), it is desirable to set the upper limit value of conditional expression (6) to 30.000. In order to further secure the effect of conditional expression (6), it is desirable to set the upper limit of conditional expression (6) to 25.000.

  In the variable magnification optical system ZL according to the present embodiment, it is desirable that one lens component of the first lens group G1 is composed of a single lens. With this configuration, the configuration of the variable magnification optical system ZL is simplified, and further miniaturization can be realized.

  In addition, it is desirable that the variable magnification optical system ZL according to the present embodiment satisfies the following conditional expression (7).

29.00 ° <ωw <60.00 ° (7)
However,
ωw: Half angle of view in the wide-angle end state

  Conditional expression (7) defines an appropriate range of the maximum half angle of view in the wide-angle end state. By satisfying this conditional expression (7), various aberrations such as coma, distortion, and field curvature can be favorably corrected while having a wide angle of view. If the lower limit of conditional expression (7) is not reached, fluctuations in spherical aberration and chromatic spherical aberration during zooming cannot be suppressed. In order to secure the effect of the conditional expression (7), it is desirable to set the lower limit value of the conditional expression (7) to 32.00 °. In order to further secure the effect of conditional expression (7), it is desirable to set the lower limit of conditional expression (7) to 35.00 °. In order to secure the effect of the conditional expression (7), it is desirable that the upper limit value of the conditional expression (7) is 55.00 °. In order to further secure the effect of the conditional expression (7), it is desirable to set the upper limit value of the conditional expression (7) to 50.00 °. In order to further secure the effect of the conditional expression (7), it is desirable to set the upper limit value of the conditional expression (7) to 45.00 °.

  In addition, it is desirable that the variable magnification optical system ZL according to the present embodiment satisfies the following conditional expression (8).

2.50 ° <ωt <22.00 ° (8)
However,
ωt: Half angle of view in telephoto end state

  Conditional expression (8) defines an appropriate range of the maximum half angle of view in the telephoto end state. By satisfying this conditional expression (8), various aberrations such as coma, distortion, and curvature of field can be favorably corrected. If the lower limit of conditional expression (8) is not reached, image blur correction (hereinafter referred to as “anti-vibration”) is performed with lens components (anti-vibration lens group Gvr) other than the most image side and most object side in the third lens group G3. Is also not preferable because the decentration coma aberration during image stabilization becomes relatively large. In order to secure the effect of the conditional expression (8), it is desirable that the lower limit value of the conditional expression (8) is 4.50 °. In order to further secure the effect of the conditional expression (8), it is desirable to set the lower limit value of the conditional expression (8) to 6.50 °. In order to secure the effect of the conditional expression (8), it is desirable that the upper limit value of the conditional expression (8) is 20.00 °. In order to further secure the effect of the conditional expression (8), it is desirable to set the upper limit value of the conditional expression (8) to 18.00 °. In order to further secure the effect of the conditional expression (8), it is desirable to set the upper limit value of the conditional expression (8) to 16.00 °.

  Note that the conditions and configurations described above each exhibit the above-described effects, and are not limited to satisfying all the conditions and configurations. The above-described effects can be obtained even if the combination of the above conditions or configurations is satisfied.

  Next, a camera that is an optical apparatus including the variable magnification optical system ZL according to the present embodiment will be described with reference to FIG. This camera 1 is a so-called mirrorless camera of interchangeable lens provided with a variable magnification optical system ZL according to the present embodiment as a photographing lens 2. In the camera 1, light from an object (subject) (not shown) is collected by the photographing lens 2 and is on the imaging surface of the imaging unit 3 via an OLPF (Optical low pass filter) (not shown). A subject image is formed on the screen. Then, the subject image is photoelectrically converted by the photoelectric conversion element provided in the imaging unit 3 to generate an image of the subject. This image is displayed on an EVF (Electronic view finder) 4 provided in the camera 1. Thus, the photographer can observe the subject via the EVF 4.

  Further, when a release button (not shown) is pressed by the photographer, an image photoelectrically converted by the imaging unit 3 is stored in a memory (not shown). In this way, the photographer can shoot the subject with the camera 1. In the present embodiment, an example of a mirrorless camera has been described. However, a variable power optical system ZL according to the present embodiment is applied to a single-lens reflex camera that has a quick return mirror in the camera body and observes a subject with a finder optical system. Even when the camera is mounted, the same effect as the camera 1 can be obtained.

  The contents described below can be appropriately adopted as long as the optical performance is not impaired.

  In the present embodiment, the variable magnification optical system ZL having the five-group configuration is shown, but the above-described configuration conditions and the like can be applied to other group configurations such as the sixth group and the seventh group. Further, a configuration in which a lens or a lens group is added closest to the object side, or a configuration in which a lens or a lens group is added closest to the image plane side may be used. Specifically, a configuration in which a lens group whose position relative to the image plane is fixed at the time of zooming or focusing is added to the most image plane side. The lens group refers to a portion having at least one lens separated by an air interval that changes at the time of zooming or focusing. The lens component refers to a single lens or a cemented lens in which a plurality of lenses are cemented.

  Alternatively, a single lens group, a plurality of lens groups, or a partial lens group may be moved in the optical axis direction to be a focusing lens group that performs focusing from an object at infinity to a near object. In this case, the focusing lens group can be applied to autofocus, and is also suitable for driving a motor for autofocus (such as an ultrasonic motor). In particular, it is preferable that at least a part of the fourth lens group G4 is a focusing lens group, and the positions of other lenses are fixed with respect to the image plane during focusing. Considering the load applied to the motor, it is preferable that the focusing lens group is composed of a single lens.

  In addition, the lens group or partial lens group is moved so as to have a displacement component perpendicular to the optical axis, or rotated (swinged) in the in-plane direction including the optical axis to correct image blur caused by camera shake. An anti-vibration lens group may be used. In particular, it is preferable that at least a part of the third lens group G3 is an anti-vibration lens group.

  Further, the lens surface may be formed as a spherical surface, a flat surface, or an aspheric surface. When the lens surface is a spherical surface or a flat surface, lens processing and assembly adjustment are facilitated, and optical performance deterioration due to errors in processing and assembly adjustment can be prevented. Further, even when the image plane is deviated, it is preferable because there is little deterioration in drawing performance. When the lens surface is an aspheric surface, the aspheric surface is an aspheric surface by grinding, a glass mold aspheric surface made of glass with an aspheric shape, or a composite aspheric surface made of resin with an aspheric shape on the glass surface. Any aspherical surface may be used. The lens surface may be a diffractive surface, and the lens may be a gradient index lens (GRIN lens) or a plastic lens.

  The aperture stop S is preferably arranged in the vicinity of or in the third lens group G3. However, the role of the aperture stop may be substituted by a lens frame without providing a member as an aperture stop.

  Further, each lens surface may be provided with an antireflection film having high transmittance in a wide wavelength region in order to reduce flare and ghost and achieve high optical performance with high contrast.

  The variable magnification optical system ZL of the present embodiment has a variable magnification ratio of about 1.8 to 10 times.

  Hereinafter, an outline of a method for manufacturing the variable magnification optical system ZL according to the present embodiment will be described with reference to FIG. First, each lens is arranged to prepare the first lens group G1, the second lens group G2, the third lens group G3, the fourth lens group G4, and the fifth lens group G5 (step S100), and from the wide-angle end state. At the time of zooming to the telephoto end state, the lens groups G1 to G5 are arranged so that the distance between them changes (step S200). Further, at the time of focusing, the fourth lens group G4 is arranged so as to move along the optical axis (step S300), and one lens component is arranged as the first lens group G1 (step S400).

  Specifically, in the present embodiment, for example, as illustrated in FIG. 1, a cemented positive lens in which a negative meniscus lens L11 having a convex surface facing the object side and a biconvex positive lens L12 are sequentially joined from the object side, and A positive meniscus lens L13 having a convex surface facing the object side is disposed to form the first lens group G1, a negative meniscus negative lens L21 having an aspherical surface provided with a resin layer on the object side lens surface, biconcave A negative lens L22 and a biconvex positive lens L23 are arranged to form the second lens group G2, and a positive meniscus lens positive lens L31 having an aspheric lens surface on the object side, an aperture stop S, an object side A cemented positive lens obtained by cementing a negative meniscus lens L32 having a convex surface toward the surface and a positive meniscus lens L33 having a convex surface toward the object side, and a biconvex positive lens L34 and the image-side lens surface are aspherical A cemented positive lens formed by cementing the negative meniscus lens-shaped negative lens L35 having a concave surface facing the object side is disposed to form the third lens group G3, and the lens surface on the image side is formed in an aspherical shape. A negative lens L41 having a negative meniscus shape is arranged as the fourth lens group G4, and a positive meniscus lens-shaped positive lens L51 having a concave surface facing the object side in which the object-side and image-side lens surfaces are formed in an aspheric shape. Is the fifth lens group G5. The lens groups thus prepared are arranged according to the above-described procedure to manufacture the variable magnification optical system ZL.

  With the configuration as described above, it is possible to provide a variable magnification optical system ZL having a small size and good optical performance, an optical apparatus having the variable magnification optical system ZL, and a method for manufacturing the variable magnification optical system ZL.

  Hereinafter, each example of the present application will be described with reference to the drawings. 1, 6, 11, 16, 21, and 26 are sectional views showing the configuration and refractive power distribution of the variable magnification optical system ZL (ZL1 to ZL6) according to each example. . In addition, in the lower part of the sectional views of these variable magnification optical systems ZL1 to ZL6, each lens group when changing the magnification from the wide-angle end state (W) to the telephoto end state (T) through the intermediate focal length state (M). The movement direction along the optical axis of G1 to G5 is indicated by an arrow.

In each embodiment, the height of the aspheric surface in the direction perpendicular to the optical axis is y, and the distance (sag amount) along the optical axis from the tangential plane of the apex of each aspheric surface to each aspheric surface at height y. Is S (y), r is the radius of curvature of the reference sphere (paraxial radius of curvature), K is the conic constant, and An is the nth-order aspherical coefficient, it is expressed by the following equation (a). . In the following examples, “E−n” indicates “× 10 ⁻ⁿ ”.

S (y) = (y ² / r) / {1+ (1−K × y ² / r ² ) ^1/2 }
+ A4 × y ⁴ + A6 × y ⁶ + A8 × y ⁸ + A10 × y ¹⁰ + A12 × y ¹² (a)

  In each embodiment, the secondary aspheric coefficient A2 is zero. In the table of each example, an aspherical surface is marked with * on the right side of the surface number.

[First embodiment]
FIG. 1 is a diagram showing a configuration of a variable magnification optical system ZL1 according to the first example. The variable magnification optical system ZL1 includes, in order from the object side, a first lens group G1 having a positive refractive power, a second lens group G2 having a negative refractive power, and a third lens group G3 having a positive refractive power. And a fourth lens group G4 having a negative refractive power and a fifth lens group G5 having a positive refractive power.

  In the variable magnification optical system ZL1, the first lens group G1 includes, in order from the object side, a cemented positive lens in which a negative meniscus lens L11 having a convex surface facing the object side and a positive meniscus lens L12 having a convex surface facing the object side are cemented. It consists of The second lens group G2 includes, in order from the object side, a biconcave negative lens L21, a biconcave negative lens L22, and a positive meniscus lens L23 having a convex surface directed toward the object side. The third lens group G3 has, in order from the object side, a positive lens L31 having a biconvex positive lens shape in which the lens surface on the object side is formed in an aspheric shape, a biconvex positive lens L32, and a concave surface facing the object side. It is composed of a cemented positive lens in which a negative meniscus lens L33 is cemented, and a cemented positive lens in which a negative meniscus lens L34 having a convex surface facing the object side and a biconvex positive lens L35 are cemented. Thus, the third lens group G3 is composed of three lens components having positive refractive power. The fourth lens group G4 includes a negative meniscus negative lens L41 having an aspheric lens surface on the image side and a convex surface facing the object side. The fifth lens group G5 includes a positive meniscus lens L51 having a convex surface directed toward the object side. The aperture stop S is disposed on the object side of the third lens group G3 (the object side of the positive lens L31). The positive lens L31 and the negative lens L41 are glass mold aspheric lenses. The first lens group G1 is composed of one lens component (junction lens). The fifth lens group G5 is composed of one lens component (single lens).

  In the variable magnification optical system ZL1, the distance between the first lens group G1 and the second lens group G2 increases during the magnification change from the wide-angle end state to the telephoto end state, and the second lens group G2 and the third lens group G3. Is decreased, the distance between the third lens group G3 and the fourth lens group G4 is increased, and the distance between the fourth lens group G4 and the fifth lens group G5 is increased. The second lens group G2, the third lens group G3, and the fourth lens group G4 are configured to move along the optical axis. The aperture stop S moves integrally with the third lens group G3. The fifth lens group G5 is fixed with respect to the image plane during zooming.

  In the variable magnification optical system ZL1, focusing from an infinite distance to a short-distance object point is performed by moving the fourth lens group G4 to the image side. The fourth lens group G4 is composed of a single lens.

  In the variable magnification optical system ZL1, image position correction (anti-shake) at the time of occurrence of camera shake is performed by stabilizing the cemented positive lens in which the biconvex positive lens L32 and the negative meniscus lens L33 are cemented in the third lens group G3. This is performed by moving the image stabilizing lens group Gvr so as to have a displacement component in a direction orthogonal to the optical axis. Note that the focal length of the entire system is f, and the image stabilization coefficient (the ratio of the image movement amount on the imaging surface to the movement amount of the image stabilization lens group Gvr in correcting the image position when camera shake occurs) is K. In order to correct the rotational shake at the angle θ, the anti-vibration lens group Gvr may be moved in the direction orthogonal to the optical axis by (f · tan θ) / K (the same applies to the following embodiments). In the first embodiment, in the wide-angle end state, the image stabilization coefficient is 0.69 and the focal length is 10.17 [mm]. Therefore, the image stabilization lens for correcting the rotation blur of 0.50 ° is used. The movement amount of the group Gvr is 0.13 [mm]. Further, in the intermediate focal length state of the first embodiment, the image stabilization coefficient is 0.86 and the focal length is 18.17 [mm], so that the rotational blur of 0.50 ° is corrected. The moving amount of the anti-vibration lens group Gvr is 0.18 [mm]. In the telephoto end state of the first embodiment, the image stabilization coefficient is 1.21, and the focal length is 48.50 [mm]. Therefore, the anti-shake for correcting the rotation blur of 0.50 ° is required. The moving amount of the vibration lens group Gvr is 0.35 [mm]. Here, the cemented positive lens in which the negative meniscus lens L34 and the biconvex positive lens L35 are cemented corresponds to the most image-side lens component G3L of the third lens group G3.

  Table 1 below lists values of specifications of the variable magnification optical system ZL1. In Table 1, f is the focal length of the entire system, FNO is the F number, ω is the half field angle, Y is the maximum image height, TL is the full length, and BF is the back focus value. This is shown for each end state, intermediate focal length state, and telephoto end state. Here, the total length TL indicates the distance on the optical axis from the most object side lens surface (first surface) to the image plane I at the time of infinite focusing. Further, the back focus BF indicates the distance (air conversion length) on the optical axis from the lens surface (32nd surface) closest to the image plane to the image plane I when focusing on infinity. In the lens data, the first column m indicates the order (surface number) of the lens surfaces from the object side along the traveling direction of the light beam, the second column r indicates the curvature radius of each lens surface, and the third column. d is the distance on the optical axis from each optical surface to the next optical surface (surface interval). The fourth column nd and the fifth column νd are the refractive index and Abbe number for the d-line (λ = 587.6 nm). Is shown. Further, the radius of curvature of 0.00000 indicates a plane, and the refractive index of air of 1.0000 is omitted. The lens group focal length indicates the number of the start surface and the focal length of each of the first to fifth lens groups G1 to G5.

  Here, the focal length f, the radius of curvature r, the surface interval d, and other length units listed in all the following specification values are generally “mm”, but the optical system is proportionally enlarged or proportional. Since the same optical performance can be obtained even if the image is reduced, the present invention is not limited to this. The description of these symbols and the description of the specification table are the same in the following embodiments.

(Table 1) First Example [Overall Specifications]
Wide-angle end state Intermediate focal length state Telephoto end state f = 10.17 to 18.17 to 48.50
FNo = 3.54 to 4.23 to 5.73
ω [°] = 38.1 to 23.7 to 9.1
Y = 6.70-7.75-7.97
TL = 71.638 to 73.782 to 93.744
BF = 12.116 to 12.116 to 12.116
BF (air equivalent length) = 12.116 to 12.116 to 12.116

[Lens data]
m r d nd νd
Object ∞
1 32.34508 0.900 1.75520 27.6
2 21.15371 4.896 1.62299 58.1
3 2495.21530 D3
4 -310.92005 0.900 1.72916 54.6
5 8.14844 4.237
6 -27.47484 0.900 1.51680 63.9
7 24.23307 0.100
8 14.46734 2.374 1.84666 23.8
9 41.08040 D9
10 0.00000 0.500 Aperture stop S
11 * 22.59721 1.859 1.62262 58.2
12 -219.49343 1.815
13 138.78758 2.736 1.65844 50.8
14 -10.05398 0.900 1.90366 31.3
15 -19.82246 2.100
16 29.47122 0.900 1.74400 44.8
17 9.09502 3.450 1.49782 82.6
18 -16.19199 D18
19 17662.68900 1.000 1.58913 61.2
20 * 19.84465 D20
21 86.05770 1.837 1.72825 28.4
22 2063.41170 12.116
Image plane ∞

[Lens focal length]
Lens group Start surface Focal length 1st lens group 1 59.03
Second lens group 4 -10.53
Third lens group 10 14.28
Fourth lens group 19 -33.72
Fifth lens group 21 123.27

  In the variable magnification optical system ZL1, the eleventh surface and the twentieth surface are formed in an aspheric shape. Table 2 below shows aspheric data, that is, the values of the conic constant K and the aspheric constants A4 to A12.

(Table 2)
[Aspherical data]
11th face K = 1.00000e + 00
A4 A6 A8 A10 A12
-7.86220e-05 4.32849e-07 -1.12684e-08 0.00000e + 00 0.00000e + 00
20th face K = 1.00000e + 00
A4 A6 A8 A10 A12
3.63605e-06 1.58785e-06 -1.92237e-07 5.32409e-09 0.00000e + 00

  In the variable magnification optical system ZL1, the axial air distance D3 between the first lens group G1 and the second lens group G2, the axial air distance D9 between the second lens group G2 and the third lens group G3, and the third lens group. As described above, the axial air distance D18 between G3 and the fourth lens group G4 and the axial air distance D20 between the fourth lens group G4 and the fifth lens group G5 change during zooming. Table 3 below shows variable intervals in the focal length states of the wide-angle end state (W), the intermediate focal length state (M), and the telephoto end state (T) in the infinitely focused state and the close-up focused state. D0 represents the distance from the most object-side surface (first surface) of the variable magnification optical system ZL1 to the object, and β represents the magnification (the same applies to the following examples).

(Table 3)
[Variable interval data]
Infinity close
W M T W M T
D0 ∞ ∞ ∞ 128.36 126.22 106.26
β − − − -0.0701 -0.1212 -0.3017
f 10.17 18.17 48.50 − − −
D3 1.325 6.599 20.512 1.325 6.599 20.512
D9 18.793 9.399 2.000 18.793 9.399 2.000
D18 1.500 2.765 3.044 2.048 4.084 8.517
D20 6.500 11.498 24.668 5.952 10.179 19.195

Table 4 below shows values corresponding to the conditional expressions in the variable magnification optical system ZL1. In Table 4, f1 is the focal length of the first lens group G1, f4 is the focal length of the fourth lens group G4, f5 is the focal length of the fifth lens group G5, and νd1 is the first lens group G1. Νd5 is the Abbe number of the lens medium constituting the fifth lens group G5 with respect to the d-line, and d12t is the first lens group G1 and the second lens group G2 in the telephoto end state. , D12w is the distance between the first lens group G1 and the second lens group G2 in the wide-angle end state, and Σ (dit-diw) ² is each lens when the magnification is changed from the wide-angle end state to the telephoto end state. Ωw represents a half angle of view in the wide-angle end state, and ωt represents a half angle of view in the telephoto end state. The description of the reference numerals is the same in the following embodiments.

(Table 4)
[Values for conditional expressions]
(1) νd1 = 58.1
(2) f1 / (d12t-d12w) = 3.077
(3) (d12t-d12w) ² / Σ (dit-diw) ² = 0.375
(4) f5 / f1 = 2.088
(5) (−f4) /f1=0.571
(6) νd5 = 28.4
(7) ωw = 38.1 °
(8) ωt = 9.1 °

  As described above, the variable magnification optical system ZL1 satisfies all the conditional expressions (1) to (8).

  FIG. 2 is a spherical aberration diagram, astigmatism diagram, distortion diagram, magnification chromatic aberration diagram, and lateral aberration diagram in the wide-angle end state, the intermediate focal length state, and the telephoto end state of the variable magnification optical system ZL1 when focusing on infinity. FIGS. 3A and 4A are lateral aberration diagrams when image blur correction is performed in the wide-angle end state, the intermediate focal length state, and the telephoto end state when focusing on infinity. 2 (b), FIG. 3 (b), FIG. 4 (b), spherical aberration diagrams, astigmatism diagrams, distortion diagrams in the wide-angle end state, the intermediate focal length state, and the telephoto end state at the close focus. The lateral chromatic aberration diagram and lateral aberration diagram are shown in FIGS. In each aberration diagram, FNO is an F number, A is a half angle of view (unit is [°]), NA is a numerical aperture, and H0 is an object height. The spherical aberration diagram shows the F-number or numerical aperture value corresponding to the maximum aperture, the astigmatism diagram and the distortion diagram show the half field angle or the maximum object height, and the lateral aberration diagram shows each half image. The value of a corner or each object height is shown. d represents a d-line (λ = 587.6 nm), and g represents a g-line (λ = 435.8 nm). In the astigmatism diagram, the solid line indicates the sagittal image plane, and the broken line indicates the meridional image plane. Also, the same reference numerals as in this example are used in the aberration diagrams of the examples shown below. From these aberration diagrams, it is understood that various aberrations are satisfactorily corrected from the wide-angle end state to the telephoto end state in the variable magnification optical system ZL1.

[Second Embodiment]
FIG. 6 is a diagram illustrating a configuration of the variable magnification optical system ZL2 according to the second example. The variable magnification optical system ZL2 includes, in order from the object side, a first lens group G1 having a positive refractive power, a second lens group G2 having a negative refractive power, and a third lens group G3 having a positive refractive power. And a fourth lens group G4 having a negative refractive power and a fifth lens group G5 having a positive refractive power.

  In the zoom optical system ZL2, the first lens group G1 includes a positive meniscus lens L11 having a convex surface directed toward the object side. The second lens group G2 includes, in order from the object side, a negative meniscus lens L21 having a convex surface directed toward the object side, a biconcave negative lens L22, and a positive meniscus lens L23 having a convex surface directed toward the object side. . Further, in the third lens group G3, in order from the object side, a positive lens L31 having a biconvex positive lens shape in which the lens surface on the object side is formed in an aspheric shape, and a lens surface in the image side are formed in an aspheric shape. The lens includes a biconvex positive lens-shaped positive lens L32 and a cemented positive lens in which a negative meniscus lens L33 having a convex surface facing the object side and a biconvex positive lens L34 are cemented. Thus, the third lens group G3 is composed of three lens components having positive refractive power. The fourth lens group G4 includes a negative meniscus negative lens L41 having an aspheric lens surface on the image side and a convex surface facing the object side. The fifth lens group G5 includes a positive meniscus lens L51 having a concave surface directed toward the object side. The aperture stop S is disposed between the positive lens L31 and the positive lens L32 of the third lens group G3. The positive lens L31, the positive lens L32, and the negative lens L41 are glass molded aspheric lenses. The first lens group G1 is composed of one lens component (single lens). The fifth lens group G5 is composed of one lens component (single lens).

  In the variable magnification optical system ZL2, the distance between the first lens group G1 and the second lens group G2 increases during the magnification change from the wide-angle end state to the telephoto end state, and the second lens group G2 and the third lens group G3. Is decreased, the distance between the third lens group G3 and the fourth lens group G4 is increased, and the distance between the fourth lens group G4 and the fifth lens group G5 is increased. The second lens group G2, the third lens group G3, and the fourth lens group G4 are configured to move along the optical axis. The aperture stop S moves integrally with the third lens group G3. The fifth lens group G5 is fixed with respect to the image plane during zooming.

  In the variable magnification optical system ZL2, focusing from an infinite distance to a short distance object point is performed by moving the fourth lens group G4 to the image side. The fourth lens group G4 is composed of a single lens.

  In the variable magnification optical system ZL2, the correction of image position (anti-shake) at the time of occurrence of camera shake is performed by using the positive lens L32 in the third lens group G3 as the anti-shake lens group Gvr, and this anti-shake lens group Gvr as the optical axis. It is performed by moving so as to have a displacement component in a direction orthogonal to the direction. That is, the anti-vibration lens group Gvr in the variable magnification optical system ZL2 is composed of a single lens. In the second embodiment, in the wide-angle end state, the image stabilization coefficient is 0.83 and the focal length is 10.30 [mm]. Therefore, the image stabilization lens for correcting the rotation blur of 0.50 ° is used. The movement amount of the group Gvr is 0.11 [mm]. Further, in the intermediate focal length state of the second embodiment, the image stabilization coefficient is 1.03 and the focal length is 18.00 [mm], so that the rotational blur of 0.50 ° is corrected. The moving amount of the anti-vibration lens group Gvr is 0.15 [mm]. Further, in the telephoto end state of the second embodiment, the image stabilization coefficient is 1.30 and the focal length is 29.10 [mm]. Therefore, the anti-shake for correcting the rotation blur of 0.50 ° is required. The moving amount of the vibration lens group Gvr is 0.20 [mm]. Here, the cemented positive lens in which the negative meniscus lens L33 and the biconvex positive lens L34 are cemented corresponds to the most image-side lens component G3L of the third lens group G3.

  Table 5 below lists values of specifications of the variable magnification optical system ZL2.

(Table 5) Second Example [Overall Specifications]
Wide-angle end state Intermediate focal length state Telephoto end state f = 10.30 to 18.00 to 29.10
FNo = 3.62 to 4.41 to 5.50
ω [°] = 37.7 to 23.9 to 15.2
Y = 6.96 to 7.83 to 7.97
TL = 61.283 to 64.483 to 73.283
BF = 13.549 to 13.549 to 13.549
BF (air equivalent length) = 13.549 to 13.549 to 13.549

[Lens data]
m r d nd νd
Object ∞
1 35.62351 3.039 1.51680 63.9
2 324.34362 D2
3 200.00000 1.000 1.69680 55.5
4 7.70916 3.406
5 -24.82548 0.850 1.58913 61.2
6 27.31877 0.157
7 14.00000 2.054 1.84666 23.8
8 44.00332 D8
9 * 33.75124 1.404 1.62263 58.2
10 -118.85028 1.500
11 0.00000 1.500 Aperture stop S
12 51.48519 1.577 1.62263 58.2
13 * -28.96931 1.500
14 19.70495 0.850 1.84666 23.8
15 9.59601 2.355 1.49782 82.6
16 -13.97847 D16
17 167.72851 0.850 1.58913 61.2
18 * 11.10365 D18
19 -55.00000 1.992 1.84666 23.8
20 -22.59467 13.549
Image plane ∞

[Lens focal length]
Lens group Start surface Focal length 1st lens group 1 77.16
Second lens group 3 -10.97
Third lens group 9 11.91
4th lens group 17 -20.22
5th lens group 19 44.05

  In the variable magnification optical system ZL2, the ninth surface, the thirteenth surface, and the eighteenth surface are formed in an aspherical shape. Table 6 below shows the aspheric data, that is, the values of the conic constant K and the aspheric constants A4 to A12.

(Table 6)
[Aspherical data]
Surface 9 K = 1.00000e + 00
A4 A6 A8 A10 A12
-1.17196e-04 -1.66927e-06 4.54983e-08 0.00000e + 00 0.00000e + 00
Surface 13 K = 1.00000e + 00
A4 A6 A8 A10 A12
3.95781e-05 -7.83445e-07 2.83596e-08 0.00000e + 00 0.00000e + 00
18th page K = 1.00000e + 00
A4 A6 A8 A10 A12
3.84742e-05 -3.95114e-06 2.48978e-07 -8.34383e-09 0.00000e + 00

  In this zoom optical system ZL2, the axial air distance D2 between the first lens group G1 and the second lens group G2, the axial air distance D8 between the second lens group G2 and the third lens group G3, and the third lens group. As described above, the axial air gap D16 between G3 and the fourth lens group G4 and the axial air gap D18 between the fourth lens group G4 and the fifth lens group G5 change during zooming. Table 7 below shows variable intervals in the focal length states of the wide-angle end state (W), the intermediate focal length state (M), and the telephoto end state (T) in the infinitely focused state and the close-up focused state.

(Table 7)
[Variable interval data]
Infinity close
W M T W M T
D0 ∞ ∞ ∞ 138.72 135.52 126.72
β − − − -0.0678 -0.1165 -0.1927
f 10.30 18.00 29.10 − − −
D2 1.800 7.462 12.655 1.800 7.462 12.655
D8 14.391 6.090 1.800 14.391 6.090 1.800
D16 1.500 3.314 4.791 1.835 4.143 6.489
D18 6.010 10.034 16.454 5.675 9.205 14.757

  Table 8 below shows values corresponding to the conditional expressions in the variable magnification optical system ZL2.

(Table 16)
[Values for conditional expressions]
(1) νd1 = 63.9
(2) f1 / (d12t−d12w) = 7.108
(3) (d12t−d12w) ² / Σ (dit-diw) ² = 0.297
(4) f5 / f1 = 0.571
(5) (−f4) /f1=0.262
(6) νd5 = 23.8
(7) ωw = 37.7 °
(8) ωt = 15.2 °

  Thus, this variable magnification optical system ZL2 satisfies all the conditional expressions (1) to (8).

  FIG. 7 shows spherical aberration diagrams, astigmatism diagrams, distortion diagrams, magnification chromatic aberration diagrams, and lateral aberration diagrams of the variable magnification optical system ZL2 in the wide-angle end state, the intermediate focal length state, and the telephoto end state at the time of focusing on infinity. (A), FIG. 8 (a), and FIG. 9 (a) are diagrams showing lateral aberrations when image blur correction is performed in the wide-angle end state, the intermediate focal length state, and the telephoto end state when focusing on infinity. 7 (b), FIG. 8 (b), and FIG. 9 (b), spherical aberration diagrams, astigmatism diagrams, distortion diagrams in the wide-angle end state, intermediate focal length state, and telephoto end state during close-up focusing. The lateral chromatic aberration diagram and lateral aberration diagram are shown in FIGS. From these aberration diagrams, it is understood that various aberrations are satisfactorily corrected from the wide-angle end state to the telephoto end state in the variable magnification optical system ZL2.

[Third embodiment]
FIG. 11 is a diagram illustrating a configuration of the variable magnification optical system ZL3 according to the third example. The variable magnification optical system ZL3 includes, in order from the object side, a first lens group G1 having a positive refractive power, a second lens group G2 having a negative refractive power, and a third lens group G3 having a positive refractive power. And a fourth lens group G4 having a negative refractive power and a fifth lens group G5 having a positive refractive power.

  In the zoom optical system ZL3, the first lens group G1 includes a positive meniscus lens L11 having a convex surface directed toward the object side. The second lens group G2 includes, in order from the object side, a negative meniscus lens L21 having a convex surface directed toward the object side, and a negative lens having a biconcave negative lens shape in which the lens surfaces on the object side and the image side are formed in an aspheric shape. L22 and a positive meniscus lens L23 having a convex surface facing the object side. Further, in the third lens group G3, in order from the object side, a positive lens L31 having a biconvex positive lens shape in which the lens surface on the object side is formed in an aspheric shape, and a lens surface in the image side are formed in an aspheric shape. The lens includes a biconvex positive lens-shaped positive lens L32 and a cemented positive lens in which a negative meniscus lens L33 having a convex surface facing the object side and a biconvex positive lens L34 are cemented. Thus, the third lens group G3 is composed of three lens components having positive refractive power. The fourth lens group G4 includes a negative meniscus negative lens L41 having an aspheric lens surface on the image side and a convex surface facing the object side. The fifth lens group G5 includes a positive meniscus lens L51 having a concave surface directed toward the object side. The aperture stop S is disposed between the positive lens L31 and the positive lens L32 of the third lens group G3. The negative lens L22, the positive lens L31, the positive lens L32, and the negative lens L41 are glass molded aspheric lenses. The first lens group G1 is composed of one lens component (single lens). The fifth lens group G5 is composed of one lens component (single lens).

  In the variable magnification optical system ZL3, when the magnification is changed from the wide-angle end state to the telephoto end state, the distance between the first lens group G1 and the second lens group G2 increases, and the second lens group G2 and the third lens group G3. Is decreased, the distance between the third lens group G3 and the fourth lens group G4 is increased, and the distance between the fourth lens group G4 and the fifth lens group G5 is increased. The second lens group G2, the third lens group G3, and the fourth lens group G4 are configured to move along the optical axis. The aperture stop S moves integrally with the third lens group G3. The fifth lens group G5 is fixed with respect to the image plane during zooming.

  In the variable magnification optical system ZL3, focusing from infinity to a short-distance object point is performed by moving the fourth lens group G4 to the image side. The fourth lens group G4 is composed of a single lens.

  In the variable magnification optical system ZL3, image position correction (anti-vibration) at the time of occurrence of camera shake is performed by using the positive lens L32 in the third lens group G3 as the anti-vibration lens group Gvr, and the anti-vibration lens group Gvr as the optical axis. It is performed by moving so as to have a displacement component in a direction orthogonal to the direction. That is, the image stabilizing lens group Gvr in the variable magnification optical system ZL3 is composed of a single lens. In the third embodiment, in the wide-angle end state, the image stabilization coefficient is 0.41 and the focal length is 10.30 [mm]. Therefore, the image stabilization lens for correcting the rotation blur of 0.50 ° is used. The movement amount of the group Gvr is 0.22 [mm]. Further, in the intermediate focal length state of the third embodiment, the image stabilization coefficient is 0.51, and the focal length is 18.00 [mm], so that the rotational blur of 0.50 ° is corrected. The moving amount of the anti-vibration lens group Gvr is 0.31 [mm]. Further, in the telephoto end state of the third embodiment, the image stabilization coefficient is 0.64 and the focal length is 29.10 [mm], so that the anti-shake for correcting the rotation blur of 0.50 ° is performed. The moving amount of the vibration lens group Gvr is 0.40 [mm]. Here, the cemented positive lens in which the negative meniscus lens L33 and the biconvex positive lens L34 are cemented corresponds to the most image-side lens component G3L of the third lens group G3.

  Table 9 below provides values of specifications of the variable magnification optical system ZL3.

(Table 9) Third Example [Overall Specifications]
Wide-angle end state Intermediate focal length state Telephoto end state f = 10.30 to 18.00 to 29.10
FNo = 3.61 to 4.40 to 5.52
ω [°] = 40.2 to 24.2 to 15.4
Y = 8.19 to 8.19 to 8.19
TL = 63.284 to 64.891 to 76.284
BF = 13.550-13.550-13.550
BF (air equivalent length) = 13.550 to 13.550 to 13.550

[Lens data]
m r d nd νd
Object ∞
1 33.61149 3.895 1.51680 63.9
2 323.38590 D2
3 200.00000 1.000 1.67003 47.1
4 7.75519 3.712
5 * -199.11981 0.850 1.62263 58.2
6 * 12.83535 1.215
7 13.51415 2.470 1.80518 25.4
8 57.19295 D8
9 * 22.27845 1.553 1.58913 61.2
10 -54.73672 1.500
11 0.00000 1.500 Aperture stop S
12 166.91413 1.403 1.58913 61.2
13 * -42.48113 1.500
14 24.65589 0.850 1.75520 27.6
15 8.64799 2.346 1.49782 82.6
16 -12.66309 D16
17 141.08623 0.850 1.62263 58.2
18 * 12.57056 D18
19 -76.77811 1.891 1.84666 23.8
20 -26.30007 13.550
Image plane ∞

[Lens focal length]
Lens group Start surface Focal length 1st lens group 1 72.25
Second lens group 3 -11.94
Third lens group 9 12.82
Fourth lens group 17 -22.22
5th lens group 19 46.45

  In the variable magnification optical system ZL3, the fifth surface, the sixth surface, the ninth surface, the thirteenth surface, and the eighteenth surface are formed in an aspherical shape. Table 10 below shows the aspheric data, that is, the values of the conic constant K and the aspheric constants A4 to A12.

(Table 10)
[Aspherical data]
Surface 5 K = 1.00000e + 00
A4 A6 A8 A10 A12
2.63618e-04 -4.56871e-06 4.40438e-08 -1.68618e-10 0.00000e + 00
6th surface K = 1.00000e + 00
A4 A6 A8 A10 A12
1.82171e-04 -6.53508e-06 7.09825e-08 -9.77402e-10 3.44260e-12
Surface 9 K = 1.00000e + 00
A4 A6 A8 A10 A12
-1.19764e-04 -1.25633e-06 1.89897e-08 0.00000e + 00 0.00000e + 00
Surface 13 K = 1.00000e + 00
A4 A6 A8 A10 A12
3.12457e-05 -9.85529e-07 2.86908e-08 0.00000e + 00 0.00000e + 00
18th page K = 1.00000e + 00
A4 A6 A8 A10 A12
3.02684e-05 4.14910e-06 -5.85881e-07 2.45691e-08 0.00000e + 00

  In this zoom optical system ZL3, the axial air gap D2 between the first lens group G1 and the second lens group G2, the axial air gap D8 between the second lens group G2 and the third lens group G3, and the third lens group. As described above, the axial air gap D16 between G3 and the fourth lens group G4 and the axial air gap D18 between the fourth lens group G4 and the fifth lens group G5 change during zooming. Table 11 below shows the variable intervals in each of the focal length states of the wide-angle end state (W), the intermediate focal length state (M), and the telephoto end state (T) in the infinitely focused state and the closest focused state.

(Table 11)
[Variable interval data]
Infinity close
W M T W M T
D0 ∞ ∞ ∞ 136.72 135.11 123.72
β − − − -0.0680 -0.1161 -0.1915
f 10.30 18.00 29.10 − − −
D2 1.800 7.059 13.463 1.800 7.059 13.463
D8 15.078 5.656 1.800 15.078 5.656 1.800
D16 1.500 3.201 3.473 1.902 4.184 5.298
D18 4.821 8.890 17.464 4.419 7.907 15.638

  Table 12 below shows values corresponding to the conditional expressions in the variable magnification optical system ZL3.

(Table 12)
[Values for conditional expressions]
(1) νd1 = 63.9
(2) f1 / (d12t-d12w) = 6.195
(3) (d12t-d12w) ² / Σ (dit-diw) ² = 0.286
(4) f5 / f1 = 0.463
(5) (-f4) /f1=0.308
(6) νd5 = 23.8
(7) ωw = 40.2 °
(8) ωt = 15.4 °

  Thus, this zoom optical system ZL3 satisfies all the conditional expressions (1) to (8).

  FIG. 12 shows spherical aberration diagrams, astigmatism diagrams, distortion diagrams, magnification chromatic aberration diagrams, and lateral aberration diagrams of the variable magnification optical system ZL3 in the wide-angle end state, the intermediate focal length state, and the telephoto end state at the time of focusing on infinity. FIGS. 13A and 14A are lateral aberration diagrams when image blur correction is performed in the wide-angle end state, the intermediate focal length state, and the telephoto end state when focusing on infinity. 12 (b), FIG. 13 (b), and FIG. 14 (b), spherical aberration diagrams, astigmatism diagrams, distortion diagrams in the wide-angle end state, the intermediate focal length state, and the telephoto end state at the close focus. The lateral chromatic aberration diagram and lateral aberration diagram are shown in FIGS. From these respective aberration diagrams, it can be seen that various aberrations are satisfactorily corrected from the wide-angle end state to the telephoto end state in the variable magnification optical system ZL3.

[Fourth embodiment]
FIG. 16 is a diagram showing a configuration of a variable magnification optical system ZL4 according to the fourth example. The variable magnification optical system ZL4 includes, in order from the object side, a first lens group G1 having a positive refractive power, a second lens group G2 having a negative refractive power, and a third lens group G3 having a positive refractive power. And a fourth lens group G4 having a negative refractive power and a fifth lens group G5 having a positive refractive power.

  In the zoom optical system ZL4, the first lens group G1 includes a positive meniscus lens L11 having a convex surface directed toward the object side. The second lens group G2 includes, in order from the object side, a negative meniscus lens L21 having a convex surface directed toward the object side, and a negative lens having a biconcave negative lens shape in which the lens surfaces on the object side and the image side are formed in an aspheric shape. L22 and a positive meniscus lens L23 having a convex surface facing the object side. Further, in the third lens group G3, in order from the object side, a positive lens L31 having a biconvex positive lens shape in which the lens surface on the object side is formed in an aspheric shape, and a lens surface in the image side are formed in an aspheric shape. The lens includes a biconvex positive lens-shaped positive lens L32 and a cemented positive lens in which a negative meniscus lens L33 having a convex surface facing the object side and a biconvex positive lens L34 are cemented. Thus, the third lens group G3 is composed of three lens components having positive refractive power. The fourth lens group G4 includes a negative lens L41 having a biconcave negative lens shape in which the image-side lens surface is formed in an aspherical shape. The fifth lens group G5 includes a positive meniscus lens L51 having a concave surface directed toward the object side. The aperture stop S is disposed between the positive lens L31 and the positive lens L32 of the third lens group G3. The negative lens L22, the positive lens L31, the positive lens L32, and the negative lens L41 are glass molded aspheric lenses. The first lens group G1 is composed of one lens component (single lens). The fifth lens group G5 is composed of one lens component (single lens).

  In the variable magnification optical system ZL4, when the magnification is changed from the wide-angle end state to the telephoto end state, the distance between the first lens group G1 and the second lens group G2 increases, and the second lens group G2 and the third lens group G3. Is decreased, the distance between the third lens group G3 and the fourth lens group G4 is increased, and the distance between the fourth lens group G4 and the fifth lens group G5 is increased. The second lens group G2, the third lens group G3, and the fourth lens group G4 are configured to move along the optical axis. The aperture stop S moves integrally with the third lens group G3. The fifth lens group G5 is fixed with respect to the image plane during zooming.

  In the variable magnification optical system ZL4, focusing from an infinite distance to a short-distance object point is performed by moving the fourth lens group G4 to the image side. The fourth lens group G4 is composed of a single lens.

  In the variable magnification optical system ZL4, image position correction (anti-vibration) at the time of occurrence of camera shake is performed by using the positive lens L32 in the third lens group G3 as the anti-vibration lens group Gvr, and the anti-vibration lens group Gvr as the optical axis. It is performed by moving so as to have a displacement component in a direction orthogonal to the direction. That is, the image stabilizing lens group Gvr in the variable magnification optical system ZL4 is composed of a single lens. In the fourth embodiment, in the wide-angle end state, the image stabilization coefficient is 0.96 and the focal length is 9.27 [mm]. Therefore, the image stabilization lens for correcting the rotation blur of 0.50 ° is used. The movement amount of the group Gvr is 0.08 [mm]. Further, in the intermediate focal length state of the fourth embodiment, the image stabilization coefficient is 1.22, and the focal length is 18.00 [mm], so that the rotational blur of 0.50 ° is corrected. The moving amount of the anti-vibration lens group Gvr is 0.13 [mm]. Further, in the telephoto end state of the fourth embodiment, since the image stabilization coefficient is 1.54 and the focal length is 29.10 [mm], the anti-shake for correcting the rotation blur of 0.50 ° is required. The moving amount of the vibration lens group Gvr is 0.17 [mm]. Here, the cemented positive lens in which the negative meniscus lens L33 and the biconvex positive lens L34 are cemented corresponds to the most image-side lens component G3L of the third lens group G3.

  Table 13 below provides values of specifications of the variable magnification optical system ZL4.

(Table 13) Fourth Example [Overall Specifications]
Wide-angle end state Intermediate focal length state Telephoto end state f = 9.27 to 18.00 to 29.10
FNo = 3.63 to 4.51 to 5.62
ω [°] = 40.7 to 23.9 to 15.2
Y = 6.80 to 7.86 to 7.97
TL = 64.283 to 67.004 to 76.283
BF = 13.549 to 13.549 to 13.549
BF (air equivalent length) = 13.549 to 13.549 to 13.549

[Lens data]
m r d nd νd
Object ∞
1 33.97551 3.713 1.51680 63.9
2 313.97719 D2
3 200.00000 1.000 1.69680 55.5
4 7.55046 4.060
5 * -38.65804 0.850 1.58913 61.2
6 * 21.29952 0.100
7 14.00000 2.227 1.84666 23.8
8 42.23084 D8
9 * 44.75981 1.317 1.62262 58.2
10 -539.86502 1.500
11 0.00000 1.500 Aperture stop S
12 34.24579 1.609 1.62262 58.2
13 * -29.07077 1.500
14 19.00255 0.850 1.90 200 25.3
15 9.43667 2.363 1.49782 82.6
16 -12.69277 D16
17 -445.11665 0.850 1.58913 61.2
18 * 11.74230 D18
19 -104.44105 1.997 1.84666 23.8
20 -27.62902 13.549
Image plane ∞

[Lens focal length]
Lens group Start surface Focal length 1st lens group 1 73.39
Second lens group 3 -10.86
Third lens group 9 11.78
Fourth lens group 17 -19.41
Fifth lens group 19 43.85

  In the variable magnification optical system ZL4, the fifth surface, the sixth surface, the ninth surface, the thirteenth surface, and the eighteenth surface are formed in an aspherical shape. Table 14 below shows aspheric data, that is, the values of the conical constant K and the aspheric constants A4 to A12.

(Table 14)
[Aspherical data]
Surface 5 K = 1.00000e + 00
A4 A6 A8 A10 A12
-5.78996e-05 1.17227e-06 -2.35038e-08 8.42883e-11 0.00000e + 00
6th surface K = 1.00000e + 00
A4 A6 A8 A10 A12
-9.12145e-05 8.05476e-07 -2.35584e-08 0.00000e + 00 0.00000e + 00
Surface 9 K = 1.00000e + 00
A4 A6 A8 A10 A12
-1.31071e-04 -1.59209e-06 2.45019e-08 0.00000e + 00 0.00000e + 00
Surface 13 K = 1.00000e + 00
A4 A6 A8 A10 A12
5.13314e-05 -5.12176e-07 1.98470e-08 0.00000e + 00 0.00000e + 00
18th page K = 1.00000e + 00
A4 A6 A8 A10 A12
2.28330e-05 -7.34466e-07 -1.38689e-07 6.30019e-09 0.00000e + 00

  In the variable magnification optical system ZL4, the axial air gap D2 between the first lens group G1 and the second lens group G2, the axial air gap D8 between the second lens group G2 and the third lens group G3, and the third lens group. As described above, the axial air gap D16 between G3 and the fourth lens group G4 and the axial air gap D18 between the fourth lens group G4 and the fifth lens group G5 change during zooming. Table 15 below shows the variable intervals in the focal length states of the wide-angle end state (W), the intermediate focal length state (M), and the telephoto end state (T) in the infinitely focused state and the close-up focused state.

(Table 15)
[Variable interval data]
Infinity close
W M T W M T
D0 ∞ ∞ ∞ 135.72 133.00 123.72
β − − − -0.0616 -0.1160 -0.1915
f 9.27 18.00 29.10 − − −
D2 1.814 8.601 13.713 1.814 8.601 13.713
D8 16.516 5.968 1.800 16.516 5.968 1.800
D16 1.501 3.393 4.413 1.768 4.173 5.948
D18 5.466 10.056 17.372 5.200 9.276 15.837

  Table 16 below shows values corresponding to the conditional expressions in the variable magnification optical system ZL4.

(Table 16)
[Values for conditional expressions]
(1) νd1 = 63.9
(2) f1 / (d12t−d12w) = 6.168
(3) (d12t-d12w) ² / Σ (dit-diw) ² = 0.279
(4) f5 / f1 = 0.597
(5) (−f4) /f1=0.264
(6) νd5 = 23.8
(7) ωw = 40.7 °
(8) ωt = 15.2 °

  Thus, this variable magnification optical system ZL4 satisfies all the conditional expressions (1) to (8).

  FIG. 17 shows spherical aberration diagrams, astigmatism diagrams, distortion diagrams, magnification chromatic aberration diagrams, and lateral aberration diagrams of the variable magnification optical system ZL4 in the wide-angle end state, the intermediate focal length state, and the telephoto end state when focusing on infinity. (A), FIG. 18 (a), and FIG. 19 (a) are lateral aberration diagrams when image blur correction is performed in the wide-angle end state, the intermediate focal length state, and the telephoto end state at the time of focusing on infinity. 17 (b), FIG. 18 (b), and FIG. 19 (b), spherical aberration diagrams, astigmatism diagrams, distortion aberration diagrams in the wide-angle end state, the intermediate focal length state, and the telephoto end state at the close focus. A lateral chromatic aberration diagram and a lateral aberration diagram are shown in FIGS. From these aberration diagrams, it is understood that various aberrations are satisfactorily corrected from the wide-angle end state to the telephoto end state in the variable magnification optical system ZL4.

[Fifth embodiment]
FIG. 21 is a diagram showing a configuration of a variable magnification optical system ZL5 according to the fifth example. The variable magnification optical system ZL5 includes, in order from the object side, a first lens group G1 having a positive refractive power, a second lens group G2 having a negative refractive power, and a third lens group G3 having a positive refractive power. And a fourth lens group G4 having a negative refractive power and a fifth lens group G5 having a positive refractive power.

  In the variable magnification optical system ZL5, the first lens group G1 includes a biconvex positive lens L11. The second lens group G2 includes, in order from the object side, a biconcave negative lens L21, a biconcave negative lens L22, and a positive meniscus lens L23 having a convex surface directed toward the object side. The third lens group G3 includes, in order from the object side, a positive lens L31 having a biconvex positive lens shape having an aspheric lens surface on the object side, a positive meniscus lens L32 having a concave surface facing the object side, and an object It consists of a cemented positive lens cemented with a negative meniscus lens L33 with a concave surface facing side, and a cemented positive lens with a negative meniscus lens L34 with a convex surface facing the object side and a biconvex positive lens L35 cemented. Thus, the third lens group G3 is composed of three lens components having positive refractive power. The fourth lens group G4 includes, in order from the object side, a positive meniscus lens L41 having a concave surface directed toward the object side and a negative lens L42 having a biconcave negative lens shape in which the image side lens surface is formed in an aspherical shape. It consists of a cemented negative lens. The fifth lens group G5 includes a cemented positive lens in which a biconvex positive lens L51 and a biconcave negative lens L52 are cemented in order from the object side. The aperture stop S is disposed on the object side of the third lens group G3 (the object side of the positive lens L31). The positive lens L31, the positive lens L32, and the negative lens L42 are glass molded aspheric lenses. The first lens group G1 is composed of one lens component (single lens). The fifth lens group G5 is composed of one lens component (junction lens).

  In the variable magnification optical system ZL5, when the magnification is changed from the wide-angle end state to the telephoto end state, the distance between the first lens group G1 and the second lens group G2 increases, and the second lens group G2 and the third lens group G3. Is decreased, the distance between the third lens group G3 and the fourth lens group G4 is increased, and the distance between the fourth lens group G4 and the fifth lens group G5 is increased. The second lens group G2, the third lens group G3, and the fourth lens group G4 are configured to move along the optical axis. The aperture stop S moves integrally with the third lens group G3. The fifth lens group G5 is fixed with respect to the image plane during zooming.

  In the variable magnification optical system ZL5, focusing from infinity to a short-distance object point is performed by moving the fourth lens group G4 to the image side.

  In the variable magnification optical system ZL5, image position correction (anti-shake) at the time of occurrence of camera shake is performed by using a cemented positive lens in which the positive meniscus lens L32 and the negative meniscus lens L33 in the third lens group G3 are cemented. The group Gvr is used, and the vibration-proof lens group Gvr is moved so as to have a displacement component in a direction orthogonal to the optical axis. In the fifth embodiment, in the wide-angle end state, the image stabilization coefficient is 0.43 and the focal length is 10.30 [mm]. Therefore, the image stabilization lens for correcting the rotation blur of 0.50 °. The movement amount of the group Gvr is 0.21 [mm]. Further, in the intermediate focal length state of the fifth embodiment, since the image stabilization coefficient is 0.56 and the focal length is 18.00 [mm], the rotation blur of 0.50 ° is corrected. The moving amount of the anti-vibration lens group Gvr is 0.28 [mm]. In the telephoto end state of the fifth embodiment, the image stabilization coefficient is 0.73 and the focal length is 30.26 [mm]. The moving amount of the vibration lens group Gvr is 0.36 [mm]. Here, the cemented positive lens in which the negative meniscus lens L34 and the biconvex positive lens L35 are cemented corresponds to the most image-side lens component G3L of the third lens group G3.

  Table 17 below provides values of specifications of the variable magnification optical system ZL5.

(Table 17) Fifth Example [Overall Specifications]
Wide-angle end state Intermediate focal length state Telephoto end state f = 10.30 to 18.00 to 30.26
FNo = 3.71 to 4.55 to 5.75
ω [°] = 37.7 to 23.9 to 14.5
Y = 6.77 to 7.77 to 7.97
TL = 64.245 to 66.885 to 79.284
BF = 12.117 to 12.117 to 12.117
BF (air equivalent length) = 12.117 to 12.117 to 12.117

[Lens data]
m r d nd νd
Object ∞
1 57.09618 2.833 1.49782 82.6
2 -83.26625 D2
3 -64.01769 0.900 1.72916 54.6
4 8.73070 2.764
5 -49.39768 0.900 1.51680 63.9
6 20.00511 0.437
7 13.86318 2.129 1.84666 23.8
8 46.07446 D8
9 0.00000 0.500 Aperture stop S
10 * 21.28713 1.806 1.62262 58.2
11 -219.49343 1.800
12 -937.71858 2.288 1.65844 50.8
13 -12.03509 0.900 1.90366 31.3
14 -23.24399 2.100
15 29.47122 0.900 1.74965 34.0
16 9.78909 2.762 1.49782 82.6
17 -16.20858 D17
18 -186.63581 1.000 2.00069 25.5
19 -30.00000 0.900 1.62940 35.4
20 * 22.83165 D20
21 70.62458 2.209 1.84666 23.8
22 -100.00000 0.900 1.72825 28.4
23 2063.41170 12.117
Image plane ∞

[Lens focal length]
Lens Group Start Surface Focal Length First Lens Group 1 68.50
Second lens group 3 -11.80
Third lens group 9 14.83
Fourth lens group 18 -48.81
5th lens group 21 78.06

  In the variable magnification optical system ZL5, the tenth surface and the twentieth surface are formed in an aspherical shape. Table 18 below shows the data of the aspheric surface, that is, the values of the conic constant K and the aspheric constants A4 to A12.

(Table 18)
[Aspherical data]
10th page K = 1.00000e + 00
A4 A6 A8 A10 A12
-7.99825e-05 1.73203e-07 -1.66026e-08 0.00000e + 00 0.00000e + 00
20th face K = 1.00000e + 00
A4 A6 A8 A10 A12
3.01138e-05 -4.83908e-07 5.39231e-10 1.40011e-11 0.00000e + 00

  In the zoom optical system ZL5, the axial air distance D2 between the first lens group G1 and the second lens group G2, the axial air distance D8 between the second lens group G2 and the third lens group G3, and the third lens group. As described above, the axial air distance D17 between G3 and the fourth lens group G4 and the axial air distance D20 between the fourth lens group G4 and the fifth lens group G5 change during zooming. Table 19 below shows variable intervals in the respective focal length states of the wide-angle end state (W), the intermediate focal length state (M), and the telephoto end state (T) in the infinite focus state and the close-up focus state.

(Table 19)
[Variable interval data]
Infinity close
W M T W M T
D0 ∞ ∞ ∞ 185.75 183.11 170.72
β − − − -0.0518 -0.0906 -0.1581
f 10.30 18.00 30.26 − − −
D2 1.800 5.650 11.395 1.800 5.650 11.395
D8 15.201 6.380 2.000 15.201 6.380 2.000
D17 1.500 3.058 2.955 2.214 4.720 6.232
D20 5.600 11.652 22.789 4.886 9.990 19.513

  Table 20 below shows values corresponding to the conditional expressions in the variable magnification optical system ZL5.

(Table 20)
[Values for conditional expressions]
(1) νd1 = 82.6
(2) f1 / (d12t-d12w) = 7.139
(3) (d12t-d12w) ² / Σ (dit-diw) ² = 0.163
(4) f5 / f1 = 1.140
(5) (−f4) /f1=0.713
(6) νd5 = 28.4
(7) ωw = 37.7 °
(8) ωt = 14.5 °

  Thus, this zoom optical system ZL5 satisfies all the conditional expressions (1) to (8).

  FIG. 22 is a spherical aberration diagram, astigmatism diagram, distortion diagram, magnification chromatic aberration diagram, and lateral aberration diagram of the variable magnification optical system ZL5 in the wide-angle end state, the intermediate focal length state, and the telephoto end state at the time of focusing on infinity. (A), FIG. 23 (a), and FIG. 24 (a) are diagrams showing lateral aberrations when image blur correction is performed in the wide-angle end state, the intermediate focal length state, and the telephoto end state when focusing on infinity. 22 (b), FIG. 23 (b), FIG. 24 (b), spherical aberration diagrams, astigmatism diagrams, distortion diagrams in the wide-angle end state, the intermediate focal length state, and the telephoto end state at the close focus. A lateral chromatic aberration diagram and a lateral aberration diagram are shown in FIGS. From these respective aberration diagrams, it is understood that various aberrations are satisfactorily corrected from the wide-angle end state to the telephoto end state in the variable magnification optical system ZL5.

[Sixth embodiment]
FIG. 26 is a diagram illustrating a configuration of the variable magnification optical system ZL6 according to the sixth example. The variable magnification optical system ZL6 includes, in order from the object side, a first lens group G1 having a positive refractive power, a second lens group G2 having a negative refractive power, and a third lens group G3 having a positive refractive power. And a fourth lens group G4 having a negative refractive power and a fifth lens group G5 having a positive refractive power.

  In the zoom optical system ZL6, the first lens group G1 includes a positive meniscus lens L11 having a convex surface directed toward the object side. The second lens group G2 includes, in order from the object side, a negative meniscus lens L21 having a convex surface directed toward the object side, a biconcave negative lens L22, and a positive meniscus lens L23 having a convex surface directed toward the object side. . The third lens group G3 has, in order from the object side, a positive lens L31 having a biconvex positive lens shape in which the lens surface on the object side is formed in an aspheric shape, a biconvex positive lens L32, and a concave surface facing the object side. It is composed of a cemented positive lens in which a negative meniscus lens L33 is cemented, and a cemented positive lens in which a negative meniscus lens L34 having a convex surface facing the object side and a biconvex positive lens L35 are cemented. Thus, the third lens group G3 is composed of three lens components having positive refractive power. The fourth lens group G4 includes, in order from the object side, a positive meniscus lens L41 having a concave surface directed toward the object side and a negative lens L42 having a biconcave negative lens shape in which the image side lens surface is formed in an aspherical shape. It consists of a cemented negative lens. The fifth lens group G5 includes a cemented positive lens in which a biconvex positive lens L51 and a biconcave negative lens L52 are cemented in order from the object side. The aperture stop S is disposed on the object side of the third lens group G3 (the object side of the positive lens L31). The positive lens L31, the positive lens L32, and the negative lens L42 are glass molded aspheric lenses. The first lens group G1 is composed of one lens component (single lens). The fifth lens group G5 is composed of one lens component (junction lens).

  In the variable magnification optical system ZL6, when the magnification is changed from the wide-angle end state to the telephoto end state, the distance between the first lens group G1 and the second lens group G2 increases, and the second lens group G2 and the third lens group G3. The distance between the third lens group G3 and the fourth lens group G4 changes, the distance between the fourth lens group G4 and the fifth lens group G5 changes, and the back focus BF changes. In addition, the first lens group G1, the second lens group G2, the third lens group G3, the fourth lens group G4, and the fifth lens group are configured to move along the optical axis. The aperture stop S moves integrally with the third lens group G3.

  In the variable magnification optical system ZL6, focusing from an infinite distance to a short-distance object point is performed by moving the fourth lens group G4 to the image side.

  In the variable magnification optical system ZL6, image position correction (anti-shake) at the time of occurrence of camera shake is performed by using a cemented positive lens obtained by cementing the positive meniscus lens L32 and the negative meniscus lens L33 in the third lens group G3. The group Gvr is used, and the vibration-proof lens group Gvr is moved so as to have a displacement component in a direction orthogonal to the optical axis. In the sixth embodiment, in the wide-angle end state, the image stabilization coefficient is 0.74 and the focal length is 10.30 [mm]. The movement amount of the group Gvr is 0.12 [mm]. In the intermediate focal length state of the sixth embodiment, the image stabilization coefficient is 0.91 and the focal length is 18.00 [mm]. The moving amount of the anti-vibration lens group Gvr is 0.17 [mm]. In the telephoto end state of the sixth embodiment, the image stabilization coefficient is 1.08 and the focal length is 30.00 [mm]. The moving amount of the vibration lens group Gvr is 0.24 [mm]. Here, the cemented positive lens in which the negative meniscus lens L34 and the biconvex positive lens L35 are cemented corresponds to the most image-side lens component G3L of the third lens group G3.

  Table 21 below provides values of specifications of the variable magnification optical system ZL6.

(Table 21) Sixth Example [Overall specifications]
Wide angle end state Intermediate focal length state Telephoto end state f = 10.30 to 18.00 to 30.00
FNo = 4.10 to 4.82 to 5.62
ω [°] = 37.7 to 23.9 to 14.9
Y = 6.77 to 7.58 to 7.80
TL = 64.247 to 65.089 to 78.749
BF = 7.838 to 16.554 to 15.244
BF (air equivalent length) = 7.838 to 16.554 to 15.244

[Lens data]
m r d nd νd
Object ∞
1 22.52929 4.999 1.49782 82.6
2 248.61062 D2
3 4865.94900 0.900 1.72916 54.6
4 8.63494 3.142
5 -64.21918 0.900 1.51680 63.9
6 13.26867 1.920
7 13.33792 1.985 1.84666 23.8
8 25.02924 D8
9 0.00000 0.500 Aperture stop S
10 * 18.92196 1.753 1.62262 58.2
11 -219.49343 1.800
12 75.77393 2.459 1.65844 50.8
13 -8.96476 0.900 1.90366 31.3
14 -17.67634 2.375
15 29.47122 0.900 1.65290 47.9
16 6.98841 2.867 1.49782 82.6
17 -20.84873 D17
18 -63.57202 1.000 2.00069 25.5
19 -30.00000 0.900 1.65816 33.0
20 * 14.81127 D20
21 22.62294 3.433 1.74682 36.0
22 -100.00000 0.900 1.74397 44.9
23 2063.41170 BF
Image plane ∞

[Lens focal length]
Lens group Start surface Focal length 1st lens group 1 49.40
Second lens group 3 -10.00
Third lens group 9 13.16
4th lens group 18 -20.36
5th lens group 21 30.57

  In the zoom optical system ZL6, the tenth surface and the twentieth surface are formed in an aspherical shape. Table 22 below shows the aspheric data, that is, the values of the conical constant K and the aspheric constants A4 to A12.

(Table 22)
[Aspherical data]
10th page K = 1.00000e + 00
A4 A6 A8 A10 A12
-7.14717e-05 2.26370e-07 3.68476e-09 0.00000e + 00 0.00000e + 00
20th face K = 1.00000e + 00
A4 A6 A8 A10 A12
-5.68760e-06 -6.85618e-07 -3.31915e-08 5.71453e-10 0.00000e + 00

  In the zoom optical system ZL6, the axial air distance D2 between the first lens group G1 and the second lens group G2, the axial air distance D8 between the second lens group G2 and the third lens group G3, and the third lens group. The axial air gap D17 between G3 and the fourth lens group G4, the axial air gap D20 between the fourth lens group G4 and the fifth lens group G5, and the back focus BF change as described above. To do. Table 23 below shows the variable intervals in each of the focal length states of the wide-angle end state (W), the intermediate focal length state (M), and the telephoto end state (T) in the infinitely focused state and the close-up focused state.

(Table 23)
[Variable interval data]
Infinity close
W M T W M T
D0 ∞ ∞ ∞ 185.91 184.85 170.99
β − − − -0.0514 -0.0907 -0.1507
f 10.30 18.00 30.00 − − −
D2 2.001 5.151 12.675 2.001 5.151 12.675
D8 13.676 4.791 2.054 13.376 4.491 1.754
D17 2.617 1.500 2.548 3.029 2.448 4.656
D20 4.483 3.461 12.597 4.071 2.513 10.489
BF 7.838 16.554 15.244 7.982 16.917 15.808

  Table 24 below shows values corresponding to the conditional expressions in the variable magnification optical system ZL6.

(Table 24)
[Values for conditional expressions]
(1) νd1 = 82.6
(2) f1 / (d12t-d12w) = 4.628
(3) (d12t-d12w) ² / Σ (dit-diw) ² = 0.362
(4) f5 / f1 = 0.619
(5) (-f4) /f1=0.512
(7) ωw = 37.7 °
(8) ωt = 14.9 °

  Thus, this variable magnification optical system ZL6 satisfies the conditional expressions (1) to (5), (7), and (8).

  FIG. 27 shows a spherical aberration diagram, an astigmatism diagram, a distortion diagram, a lateral chromatic aberration diagram, and a lateral aberration diagram in the wide-angle end state, the intermediate focal length state, and the telephoto end state of the variable magnification optical system ZL6 when focusing on infinity. (A), FIG. 28 (a), and FIG. 29 (a) are diagrams showing lateral aberrations when image blur correction is performed in the wide-angle end state, the intermediate focal length state, and the telephoto end state when focusing on infinity. 27 (b), FIG. 28 (b), and FIG. 29 (b), a spherical aberration diagram, an astigmatism diagram, a distortion aberration diagram in the wide-angle end state, the intermediate focal length state, and the telephoto end state at the close focus. A lateral chromatic aberration diagram and a lateral aberration diagram are shown in FIGS. From these aberration diagrams, it can be seen that the variable magnification optical system ZL6 is well corrected for various aberrations from the wide-angle end state to the telephoto end state.

ZL (ZL1 to ZL6) Variable magnification optical system G1 First lens group G2 Second lens group G3 Third lens group G4 Fourth lens group G5 Fifth lens group Gvr Anti-vibration lens group 1 Camera (optical device)

Claims (14)

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;
A fifth lens group having a positive refractive power,
At the time of zooming from the wide-angle end state to the telephoto end state, the distance between the first lens group and the second lens group changes, and the distance between the second lens group and the third lens group changes, The distance between the third lens group and the fourth lens group changes, the distance between the fourth lens group and the fifth lens group changes,
During focusing, the fourth lens group moves along the optical axis,
The zoom lens system according to claim 1, wherein the first lens group includes one lens component.
The lens component indicates a single lens or a cemented lens.   2. The variable magnification optical system according to claim 1, wherein the fifth lens group is fixed with respect to the image plane during zooming. 3. The variable magnification optical system according to claim 1, wherein the first lens group includes a lens that satisfies a condition of the following expression. 4.
40.000 <νd1
However,
νd1: Abbe number for the d-line of the medium of the lens constituting the first lens group The zoom lens system according to any one of claims 1 to 3, wherein a condition of the following formula is satisfied.
2.000 <f1 / (d12t-d12w) <8.00
However,
d12t: Distance between the first lens group and the second lens group in the telephoto end state d12w: Distance between the first lens group and the second lens group in the wide-angle end state f1: Focal length of the first lens group The zoom lens system according to any one of claims 1 to 4, wherein a condition of the following formula is satisfied.
0.120 <(d12t-d12w) ² / Σ (dit-diw) ² <0.900
However,
d12t: Distance between the first lens group and the second lens group in the telephoto end state d12w: Distance between the first lens group and the second lens group in the wide-angle end state Σ (dit-diw) ² : Wide-angle end Sum of squares of the amount of change between each lens group when zooming from the lens to the telephoto end The zoom lens system according to any one of claims 1 to 5, wherein a condition of the following formula is satisfied.
0.800 <f5 / f1 <4.100
However,
f5: focal length of the fifth lens group f1: focal length of the first lens group The zoom lens system according to any one of claims 1 to 6, wherein a condition of the following formula is satisfied.
0.400 <(− f4) / f1 <3,000
However,
f4: focal length of the fourth lens group f1: focal length of the first lens group   The variable power optical system according to any one of claims 1 to 7, wherein the fifth lens group includes a single lens. The variable power optical system according to claim 1, wherein the fifth lens group includes a lens that satisfies a condition of the following expression.
νd5 ≦ 35.000
However,
νd5: Abbe number for the d-line of the medium of the lens constituting the fifth lens group   The variable power optical system according to any one of claims 1 to 9, wherein one lens component of the first lens group is configured by a single lens. The variable magnification optical system according to claim 1, wherein the condition of the following formula is satisfied.
29.00 ° <ωw <60.00 °
However,
ωw: Half angle of view at wide-angle end The zoom lens system according to any one of claims 1 to 11, wherein a condition of the following formula is satisfied.
2.50 ° <ωt <22.00 °
However,
ωt: Half angle of view in telephoto end state   An optical apparatus comprising the variable magnification optical system according to claim 1. In order from the object side, a first lens group having a positive refractive power, a second lens group having a negative refractive power, a third lens group having a positive refractive power, and a fourth lens having a negative refractive power A variable magnification optical system having a group and a fifth lens group having a positive refractive power,
At the time of zooming from the wide-angle end state to the telephoto end state, the distance between the first lens group and the second lens group changes, and the distance between the second lens group and the third lens group changes, The distance between the third lens group and the fourth lens group is changed, and the distance between the fourth lens group and the fifth lens group is changed.
The fourth lens group is arranged to move along the optical axis at the time of focusing,
A method of manufacturing a variable magnification optical system, wherein one lens component is arranged as the first lens group.