Imaging optical system

Abstract

To provide a compact imaging optical system which offers small open F-numbers over an entire zoom range.SOLUTION: An imaging optical system provided herein consists of a first lens group G1 having positive refractive power, a second lens group G2 having negative refractive power, and a rear lens group GR having positive refractive power arranged in order from the object side, the rear lens group GR consisting of multiple lens groups including a focusing lens group GF configured to move while shifting focus from an object at infinity to a nearby object. The imaging optical system satisfies predetermined conditional expressions.SELECTED DRAWING: Figure 1

Description

Technical Field

[0001] The present invention relates to an imaging optical system suitable for a photographing lens used in a digital camera, a video camera, and the like.

Background Art

[0002] In recent years, so-called mirrorless cameras that eliminate a quick return mirror disposed between an imaging optical system and an imaging device and guide light rays to a finder optical system have become widespread. Since the housing of a mirrorless camera is downsized by eliminating the mirror, downsizing of the imaging optical system has been demanded accordingly. In addition, a large-aperture zoom lens with a small open F-number throughout the zoom range has been demanded.

Prior Art Documents

Patent Documents

[0003]

Patent Document 1

Patent Document 2

Summary of the Invention

Problems to be Solved by the Invention

[0004] In Patent Document 1, a bright positive-lead type zoom lens with an open F-number of about 2.8 is disclosed. However, there is a problem that the size of the imaging optical system is large. In addition, in Patent Document 2, a positive-lead type zoom lens with a downsized imaging optical system is disclosed. However, there is a problem that the open F-number at the telephoto end is as dark as about 6.3.

[0005] The present invention has been made in view of such a situation, and an object thereof is to provide a small imaging optical system with a small open F-number throughout the zoom range.

Means for Solving the Problems

[0006] In order to achieve the above object, the imaging optical system of the present invention comprises, 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 rear lens group GR having a positive refractive power. The rear lens group GR comprises a plurality of lens groups including a focusing lens group GF that moves during focusing from an infinite object to a close-distance object, and satisfies the following conditional expressions. (1) 1.80 < f1 / fRW < 5.50 (2) 12.0 < LTW×FnoT / Ymax < 30.0 However, f1: Focal length of the first lens group G1 fRW: Focal length of the rear lens group GR at infinity focus at the wide-angle end LTW: Overall optical length of the imaging optical system at the wide-angle end FnoT: Aperture value at infinity focus of the imaging optical system at the telephoto end Ymax: Maximum image height of the imaging optical system

[0007] Also, in the imaging optical system of the present invention, preferably, the lens group located closest to the image plane in the rear lens group GR is fixed with respect to the image plane.

[0008] Also, in the imaging optical system of the present invention, preferably, it satisfies the following conditional expression. (3) 2.00 < f1 / fW < 6.00 However, f1: Focal length of the first lens group G1 fW: Focal length at infinity focus of the imaging optical system at the wide-angle end

[0009] Also, in the imaging optical system of the present invention, preferably, it satisfies the following conditional expression. (4) 4.00 < f1 / |f2| < 6.50 However, f1: Focal length of the first lens group G1 f2: Focal length of the second lens group G2

[0010] In addition, in the imaging optical system for implementing the present invention, preferably, the first lens group G1 is composed of one negative lens and one positive lens.

[0011] In addition, in the imaging optical system for implementing the present invention, preferably, the following conditional expressions are satisfied. (5) 1.70 < nd1ave However, nd1ave: Average value of the refractive indices with respect to the d-line of all the lenses constituting the first lens group G1

[0012] In addition, in the imaging optical system for implementing the present invention, preferably, the rear lens group GR has a negative lens, and the negative lens located closest to the object side among them satisfies the following conditional expression. (6) νdRn < 50 (7) PgFRn + 0.0024 × νdRn < 0.675 However, νdRn: Abbe number with respect to the d-line of the negative lens located closest to the object side among the negative lenses included in the rear lens group GR PgFRn: Partial dispersion ratio with respect to the g-line and F-line of the negative lens located closest to the object side among the negative lenses included in the rear lens group GR

[0013] In addition, in the imaging optical system for implementing the present invention, preferably, the rear lens group GR is composed of a third lens group G3 having a positive refractive power from the object side, a fourth lens group G4 having a positive or negative refractive power, a fifth lens group G5 having a negative refractive power, and a sixth lens group G6 having a positive refractive power. The fourth lens group G4 moves along the optical axis during focusing from an infinite object to a close object and satisfies the following conditional expression. (8) 0.40 < |f4| / fT < 1.50 However, f4: Focal length of the fourth lens group G4 fT: Focal length at infinity focusing of the imaging optical system at the telephoto end

[0014] In addition, in the imaging optical system for implementing the present invention, preferably, during zooming, the third lens group G3 and the fifth lens group G5 move along the same locus.

[0015] In addition, the imaging optical system for implementing the present invention preferably satisfies the following conditional expressions. (9) BFT / Ymax < 2.00 However, BFT: Back focus of the imaging optical system at the telephoto end Ymax: Maximum image height of the imaging optical system

[0016] In addition, the imaging optical system for implementing the present invention preferably satisfies the following conditional expressions. (10) 0.80 < M1 / fW < 2.00 However, M1: Movement amount in zooming from the wide-angle end to the telephoto end of the first lens group G1 fW: Focal length at infinity focus of the imaging optical system at the wide-angle end

[0017] In addition, the imaging optical system for implementing the present invention, the rear lens group GR has an anti-vibration lens group GS that moves including a component in a direction perpendicular to the optical axis, and satisfies the following conditional expression. (11) 0.50 < |fS| / fW < 4.0 However, fS: Focal length of the anti-vibration lens group GS fW: Focal length at infinity focus of the imaging optical system at the wide-angle end

Advantages of the Invention

[0018] According to the imaging optical system for implementing the present invention, it is possible to provide an imaging optical system with a small aperture value throughout the zoom range and a small size.

Brief Description of the Drawings

[0019]

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Mode for Carrying Out the Invention

[0020] Hereinafter, embodiments of the present invention will be described. When the refractive indices with respect to the g-line (wavelength 435.8 nm), F-line (wavelength 486.1 nm), d-line (wavelength 587.6 nm), and C-line (wavelength 656.3 nm) are ng, nF, nd, and nC, respectively, the Abbe number νd and the partial dispersion ratio θgF are expressed by the following formulas. νd = (nd - 1) / (nF - nC) θgF = (ng - nF) / (nF - nC)

[0021] As can be seen from FIGS. 1, 17, 33, 49, 65, 81, 97, 113, 129, 145, and 161, the imaging optical system of the present invention 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 rear lens group GR having a positive refractive power. The rear lens group GR includes a focusing lens group GF that moves during focusing from an infinite object to a close object, and is characterized by satisfying the following conditional expressions. (1) 1.80 < f1 / fRW < 5.50 (2) 12.0 < LTW × FnoT / Ymax < 30.0 However, f1: Focal length of the first lens group G1 fRW: Focal length of the rear lens group GR at infinity focus at the wide-angle end LTW: Overall optical length of the imaging optical system at the wide-angle end FnoT: Aperture F value at infinity focus of the imaging optical system at the telephoto end Ymax: Maximum image height of the imaging optical system

[0022] By defining the ratio of the focal length of the first lens group G1 to the rear lens group GR at the wide-angle end in conditional expression (1), both miniaturization and correction of various aberrations are achieved simultaneously.

[0023] When the refractive power of the first lens group G1 becomes weaker beyond the upper limit of conditional expression (1), the movement amount of the first lens group G1 during zooming increases. As a result, the mechanisms required for movement increase, leading to an increase in the size of the lens barrel. Also, since the overall optical length at the telephoto end becomes longer, it becomes difficult to ensure the peripheral light quantity ratio at the telephoto end. To ensure the peripheral light quantity ratio, it is necessary to increase the diameter of the first lens group G1, which leads to an increase in the size of the imaging optical system. Further, when the refractive power of the rear lens group GR becomes stronger, it becomes difficult to suppress spherical aberration and coma aberration generated in the rear lens group GR.

[0024] When the refractive power of the first lens group G1 becomes stronger beyond the lower limit of conditional expression (1), it becomes difficult to suppress the astigmatism generated in the first lens group G1. Also, when the refractive power of the rear lens group GR becomes weaker, the action of converging the light beam diffused by the second lens group G2 becomes weaker. Therefore, the overall length of the rear lens group GR becomes longer and the diameter becomes larger, leading to an increase in the size of the imaging optical system.

[0025] Regarding conditional expression (1), preferably, by limiting its lower limit value to 2.20 and its upper limit value to 4.50, the above-described effects can be made more certain.

[0026] By defining the ratio of the overall optical length at the wide-angle end of the imaging optical system, the open F value at the telephoto end, and the maximum image height in conditional expression (2), ensuring the brightness of the imaging optical system, miniaturization, and correction of various aberrations are achieved.

[0027] Generally, the lower the F-number of an optical system, the higher the on-axis ray passing through the optical system. Also, the higher the maximum image height, the higher the off-axis ray passing through the group closest to the object side or the image plane side. This corresponds to a decrease in the component of FnoT / Ymax in conditional expression (2). To correct various aberrations in such a situation, it is effective to increase the overall length of the optical system and make the incident rays on each surface in the optical system gentler. However, in order to achieve miniaturization, it is necessary to appropriately set the overall length according to the F-number at the telephoto end and the maximum image height.

[0028] When the overall optical length at the wide-angle end exceeds the upper limit of conditional expression (2) and becomes large with respect to the ratio of the F-number at the telephoto end and the maximum image height, various aberrations generated in the entire system are likely to be suppressed, but the overall length of the optical system becomes long. Or, the F-number at the telephoto end becomes large, making it difficult to achieve a bright optical system.

[0029] When the overall optical length at the wide-angle end is less than the lower limit of conditional expression (2) with respect to the ratio of the F-number at the telephoto end and the maximum image height, the overall length can be kept short, but since the refraction of the rays in the optical system becomes strong, the aberrations generated in each group increase, and it becomes difficult to satisfactorily correct fluctuations such as astigmatism, spherical aberration, and coma aberration mainly during zooming.

[0030] Still, for conditional expression (2), preferably, by limiting its lower limit value to 15.0 and its upper limit value to 26.0, the above-mentioned effects can be made more certain. Furthermore, in order to achieve an optical system with a smaller F-number and a shorter overall length at the more telephoto end, by limiting the upper limit value to 21.0, an optical system with a smaller F-number and a shorter overall length at the telephoto end can be achieved.

[0031] Furthermore, in the imaging optical system of the present invention, it is desirable that the lens group located closest to the image plane is fixed with respect to the image plane. By fixing the lens group located closest to the image plane during zooming, the mechanism required for zooming can be simplified, and miniaturization of the lens barrel becomes possible.

[0032] Furthermore, in the imaging optical system of the present invention, it is desirable to satisfy the following conditional expression. (3) 2.00 < f1 / fW < 6.00 However, f1: Focal length of the first lens group G1 fW: Focal length at infinity focus of the imaging optical system at the wide-angle end

[0033] By defining the ratio of the focal length of the first lens group G1 to that of the imaging optical system at the wide-angle end, conditional expression (3) achieves both miniaturization and correction of various aberrations.

[0034] If the refractive power of the first lens group G1 becomes weaker beyond the upper limit of conditional expression (3), the movement amount during zooming of the first lens group G1 increases, resulting in an increase in the mechanisms required for movement and causing the lens barrel to become larger. Also, as the overall optical length at the telephoto end becomes longer, it becomes difficult to ensure the peripheral light quantity ratio at the telephoto end, and to ensure the peripheral light quantity ratio, it is necessary to increase the diameter of the first lens group G1, leading to an increase in the size of the imaging optical system.

[0035] If the refractive power of the first lens group G1 becomes stronger beyond the lower limit of conditional expression (3), it becomes difficult to suppress the spherical aberration and astigmatism generated in the first lens group G1.

[0036] Furthermore, for conditional expression (3), preferably, by limiting the lower limit value to 2.50 and the upper limit value to 5.00, the above-described effects can be made more certain.

[0037] Furthermore, in the imaging optical system of the present invention, it is desirable to satisfy the following conditional expression. (4) 4.00 < f1 / |f2| < 6.50 However, f1: Focal length of the first lens group G1 f2: Focal length of the second lens group G2

[0038] By defining the ratio of the focal lengths of the first lens group G1 and the second lens group G2, conditional expression (4) achieves both compactification and correction of various aberrations.

[0039] If the refractive power of the first lens group G1 becomes weaker beyond the upper limit of conditional expression (4), the amount of movement during zooming of the first lens group G1 increases, so that the mechanisms required for movement increase, leading to an increase in the size of the lens barrel. In addition, since the overall optical length at the telephoto end becomes longer, it becomes difficult to ensure the peripheral light quantity ratio at the telephoto end, and in order to ensure the peripheral light quantity ratio, it is necessary to increase the diameter of the first lens group G1, leading to an increase in the size of the imaging optical system. Further, if the refractive power of the second lens group G2 becomes stronger, it becomes difficult to suppress the coma aberration at the telephoto end and the astigmatism at the wide-angle end generated in the second lens group G2.

[0040] If the refractive power of the first lens group G1 becomes stronger beyond the lower limit of conditional expression (4), it becomes difficult to suppress the astigmatism generated in the first lens group G1. Further, if the refractive power of the second lens group G2 becomes weaker, the amount of movement of the second lens group G2 during zooming increases, and the mechanisms required for movement increase, leading to an increase in the size of the lens barrel.

[0041] Incidentally, regarding conditional expression (4), it is desirable to limit the lower limit value thereof to 4.30 and the upper limit value to 5.70, so that the above-described effects can be made more certain.

[0042] Furthermore, in the imaging optical system of the present invention, it is desirable that the first lens group G1 be composed of one negative lens and one positive lens. By configuring the first lens group G1 with two lenses, the overall length of the first lens group G1 can be kept short, and further, by simplifying the structure for holding the lenses, the imaging optical system can be miniaturized. In addition, by combining a negative lens and a positive lens, chromatic aberration generated in the first lens group G1 can be suppressed.

[0043] Furthermore, in the imaging optical system of the present invention, it is desirable to satisfy the following conditional expression. (5) 1.70 < nd1ave However, nd1ave: The average value of the refractive indices with respect to the d-line of all the lenses constituting the first lens group G1

[0044] Conditional expression (5) defines the average value of the refractive indices of all the lenses constituting the first lens group G1.

[0045] When the refractive index of the lens constituting the first lens group G1 becomes smaller than the lower limit of conditional expression (5), the radius of curvature of the lens surface becomes smaller, making it difficult to correct coma aberration.

[0046] Furthermore, regarding conditional expression (5), preferably by limiting its lower limit value to 1.76, the above-described effect can be made more certain.

[0047] Furthermore, in the imaging optical system of the present invention, the rear lens group GR has a negative lens, and it is desirable that the negative lens located closest to the object side among them satisfies the following conditional expressions. (6) νdRn < 50 (7) PgFRn + 0.0024 × νdRn < 0.675 However, νdRn: Abbe number with respect to the d-line of the negative lens located closest to the object side among the negative lenses included in the rear lens group GR PgFRn: Partial dispersion ratio with respect to the g-line and F-line of the negative lens located closest to the object side among the negative lenses included in the rear lens group GR

[0048] Conditional expressions (6) and (7) define preferable optical characteristics for the material of the negative lens located closest to the object side among the negative lenses included in the rear lens group GR in order to correct chromatic aberration well. By using a high-dispersion optical material having negative anomalous partial dispersibility as the material of the negative lens located closest to the object side among the negative lenses included in the rear lens group GR, chromatic aberration fluctuations including secondary spectrum during zooming are suppressed.

[0049] When the Abbe number of the negative lens located closest to the object side among the negative lenses included in the rear lens group GR becomes smaller than the upper limit of conditional expression (6), the color cancellation effect in the rear lens group GR becomes smaller, making it difficult to suppress chromatic aberration.

[0050] Furthermore, regarding conditional expression (6), preferably by limiting its upper limit value to 41.0, the above-described effect can be made more certain.

[0051] Among the negative lenses of the rear lens group GR that exceed the upper limit of conditional expression (7), when the abnormal partial dispersibility of the negative lens located closest to the object side becomes small, the effect of achromatism including secondary spectrum in the rear lens group GR becomes small, and it becomes difficult to suppress chromatic aberration.

[0052] In addition, regarding conditional expression (7), preferably, by limiting the upper limit value thereof to 0.672, the above-described effect can be made more certain.

[0053] Furthermore, in the imaging optical system of the present invention, the rear lens group GR is composed of a third lens group G3 having a positive refractive power from the object side, a fourth lens group G4 having a positive or negative refractive power, a fifth lens group G5 having a negative refractive power, and a sixth lens group G6 having a positive refractive power. The fourth lens group G4 moves along the optical axis when focusing from an infinite object to a near-distance object, and preferably satisfies the following conditional expression. (8) 0.40 < |f4| / fT < 1.50 However, f4: Focal length of the fourth lens group G4 fT: Focal length at infinity focus of the imaging optical system at the telephoto end

[0054] Conditional expression (8) stipulates the ratio of the focal length of the fourth lens group G4 that moves during focusing to the focal length of the imaging optical system at the telephoto end, thereby achieving both miniaturization and correction of various aberrations.

[0055] When the refractive power of the fourth lens group G4 becomes weaker beyond the upper limit of conditional expression (8), the moving distance during focusing of the fourth lens group G4 becomes large, so it becomes difficult to shorten the overall length of the optical system.

[0056] When the refractive power of the fourth lens group G4 becomes stronger beyond the lower limit of conditional expression (8), it becomes difficult to suppress the astigmatism generated in the fourth lens group G4, and the aberration variation during focusing becomes large. Also, the amount of aberration variation when the fourth lens group G4 is decentered becomes large, which is not preferable.

[0057] Furthermore, for conditional expression (8), preferably by limiting its lower limit value to 0.45 and its upper limit value to 1.20, the above-described effects can be made more certain.

[0058] Furthermore, in the imaging optical system of the present invention, when zooming, it is desirable that the third lens group G3 and the fifth lens group G5 move along the same locus. Thereby, the mechanisms required for the movement of the third lens group G3 and the fifth lens group G5 during zooming can be made the same, the structure can be simplified, and the lens barrel can be miniaturized.

[0059] Furthermore, in the imaging optical system of the present invention, it is desirable to satisfy the conditional expressions shown below. (9) BFT / Ymax < 2.00 However, BFT: The back focus of the imaging optical system at the telephoto end Ymax: The maximum image height of the imaging optical system

[0060] Conditional expression (9) defines the ratio of the back focus to the maximum image height in the imaging optical system, enabling miniaturization. Here, the back focus is the air-equivalent length on the optical axis from the most image-side surface of the rear lens group GR to the image plane.

[0061] If the back focus becomes large beyond the upper limit of conditional expression (9), the overall length becomes long, which is not preferable.

[0062] Furthermore, for conditional expression (9), preferably by limiting its upper limit value to 1.65, the above-described effects can be made more certain.

[0063] Furthermore, in the imaging optical system of the present invention, it is desirable to satisfy the conditional expressions shown below. (10) 0.80 < M1 / fW < 2.00 However, M1: The movement amount in the zooming from the wide-angle end to the telephoto end of the first lens group G1 fW: The focal length at infinity focus of the imaging optical system at the wide-angle end

[0064] The conditional expression (10) enables miniaturization by defining the movement amount of the first lens group G1 from the wide-angle end to the telephoto end and the overall optical length of the imaging optical system at the wide-angle end.

[0065] If the movement amount of the first lens group G1 from the wide-angle end to the telephoto end exceeds the upper limit of the conditional expression (10), the mechanism required for movement increases, leading to an increase in the size of the lens barrel. Also, since the overall optical length at the telephoto end becomes longer, it becomes difficult to ensure the peripheral light quantity ratio at the telephoto end, and in order to ensure the peripheral light quantity ratio, it is necessary to increase the diameter of the first lens group G1, resulting in an increase in the size of the imaging optical system, which is not preferable.

[0066] If the movement amount of the first lens group G1 from the wide-angle end to the telephoto end is less than the lower limit of the conditional expression (10), it becomes necessary to increase the refractive power of the first lens group G1, making it difficult to suppress the spherical aberration and astigmatism generated in the first lens group G1.

[0067] Regarding the conditional expression (10), preferably, by limiting its lower limit value to 0.95 and its upper limit value to 1.70, the above-described effects can be made more certain.

[0068] Furthermore, in the imaging optical system of the present invention, the rear lens group GR has an anti-vibration lens group GS that moves including a component in the direction perpendicular to the optical axis, and it is desirable to satisfy the conditional expression shown below. (11) 0.50 < |fS| / fW < 4.0 However, fS: Focal length of the anti-vibration lens group GS fW: Focal length of the imaging optical system at infinity focus at the wide-angle end

[0069] The conditional expression (11) enables both a high anti-vibration effect and good imaging performance by defining the ratio of the anti-vibration lens group GS to the focal length of the imaging optical system at infinity focus at the wide-angle end.

[0070] If the refractive power of the anti-vibration lens group GS becomes smaller than the upper limit of the conditional expression (11), the movement amount during anti-vibration increases, leading to a decrease in the responsiveness of anti-vibration and an increase in the size of the lens barrel.

[0071] When the refractive power of the anti-vibration lens group GS exceeds the lower limit of the conditional expression (11), the aberration variation during anti-vibration increases.

[0072] Furthermore, regarding the conditional expression (11), it is desirable to limit its lower limit value to 0.80 and its upper limit value to 2.20, so that the above-described effects can be made more certain.

[0073] Next, the lens configuration of an embodiment according to the imaging optical system of the present invention will be described. In the following description, the lens configuration will be described in the order from the object side to the image plane side.

Embodiment

[0074] FIG. 1 is a lens configuration diagram of the imaging optical system according to Embodiment 1 of the present invention.

[0075] The imaging optical system of Embodiment 1 includes a first lens group G1 having a positive refractive power, a second lens group G2 having a negative refractive power, an aperture stop, a third lens group G3 having a positive refractive power, a fourth lens group G4 having a negative refractive power, a fifth lens group G5 having a negative refractive power, and a sixth lens group G6 having a positive refractive power. When zooming from the wide-angle end to the telephoto end, the distance between the first lens group G1 and the second lens group G2 increases, the distance between the second lens group G2 and the third lens group G3 decreases, 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, the distance between the fifth lens group G5 and the sixth lens group G6 increases, the third lens group G3 and the fifth lens group G5 move along the same locus, and the sixth lens group G6 is fixed with respect to the image plane. The fourth lens group G4 is a focusing lens group GF, and moves toward the image plane side along the optical axis when focusing from an infinite object to a close object. The rear lens group GR corresponds to the third lens group G3, the fourth lens group G4, the fifth lens group G5, and the sixth lens group G6.

[0076] The first lens group G1 consists of a cemented lens of a concave meniscus lens L1 with a convex surface facing the object side and a convex meniscus lens L2 with a convex surface facing the object side. The second lens group G2 consists of a concave meniscus lens L3 with a convex surface facing the object side and an aspherical R1 surface, a cemented lens of a biconcave lens L4 and a biconvex lens L5, and a concave meniscus lens L6 with a convex surface facing the image plane side. The third lens group G3 consists of a biconvex lens L7 with both R1 and R2 surfaces being aspherical, a cemented lens of a biconcave lens L8 and a convex meniscus lens L9 with a convex surface facing the object side, and a biconvex lens L10 with both R1 and R2 surfaces being aspherical. The biconvex lens L10 is an anti-vibration lens group GS, and during anti-vibration, it moves including a component in a direction perpendicular to the optical axis. The fourth lens group G4 consists of a concave meniscus lens L11 with a convex surface facing the object side. The fifth lens group G5 consists of a biconcave lens L12. The sixth lens group G6 consists of a biconvex lens L13.

Embodiment

[0077] FIG. 17 is a lens configuration diagram of the imaging optical system according to Embodiment 2 of the present invention.

[0078] The imaging optical system of Embodiment 2 includes a first lens group G1 having a positive refractive power, a second lens group G2 having a negative refractive power, an aperture stop, a third lens group G3 having a positive refractive power, a fourth lens group G4 having a negative refractive power, a fifth lens group G5 having a negative refractive power, and a sixth lens group G6 having a positive refractive power. When zooming from the wide-angle end to the telephoto end, the distance between the first lens group G1 and the second lens group G2 increases, the distance between the second lens group G2 and the third lens group G3 decreases, 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, the distance between the fifth lens group G5 and the sixth lens group G6 increases, the third lens group G3 and the fifth lens group G5 move along the same trajectory, and the sixth lens group G6 is fixed with respect to the image plane. The fourth lens group G4 is a focusing lens group GF, and during focusing from an infinite object to a close object, it moves toward the image plane side along the optical axis. The rear lens group GR corresponds to the third lens group G3, the fourth lens group G4, the fifth lens group G5, and the sixth lens group G6.

[0079] The first lens group G1 consists of a cemented lens of a concave meniscus lens L1 with its convex surface facing the object side and a convex meniscus lens L2 with its convex surface facing the object side. The second lens group G2 consists of a concave meniscus lens L3 with its convex surface facing the object side and an aspherical R1 surface, a cemented lens of a biconcave lens L4 and a biconvex lens L5, and a concave meniscus lens L6 with its convex surface facing the image side. The third lens group G3 consists of a biconvex lens L7 with both R1 and R2 surfaces being aspherical, a cemented lens of a concave meniscus lens L8 with its convex surface facing the object side and a convex meniscus lens L9 with its convex surface facing the object side, and a biconvex lens L10 with both R1 and R2 surfaces being aspherical. The biconvex lens L10 is an anti-vibration lens group GS, and during anti-vibration, it moves with a component in a direction perpendicular to the optical axis. The fourth lens group G4 consists of a concave meniscus lens L11 with its convex surface facing the object side. The fifth lens group G5 consists of a biconcave lens L12. The sixth lens group G6 consists of a biconvex lens L13.

Embodiment

[0080] FIG. 33 is a lens configuration diagram of the imaging optical system according to Embodiment 3 of the present invention.

[0081] The imaging optical system according to Embodiment 3 includes a first lens group G1 having a positive refractive power, a second lens group G2 having a negative refractive power, an aperture stop, a third lens group G3 having a positive refractive power, a fourth lens group G4 having a negative refractive power, a fifth lens group G5 having a negative refractive power, and a sixth lens group G6 having a positive refractive power. When zooming from the wide-angle end to the telephoto end, the distance between the first lens group G1 and the second lens group G2 increases, the distance between the second lens group G2 and the third lens group G3 decreases, 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, the distance between the fifth lens group G5 and the sixth lens group G6 increases, the third lens group G3 and the fifth lens group G5 move along the same locus, and the sixth lens group G6 is fixed with respect to the image plane. The fourth lens group G4 is a focusing lens group GF, and during focusing from an infinite object to a close object, it moves toward the image side along the optical axis. The rear lens group GR corresponds to the third lens group G3, the fourth lens group G4, the fifth lens group G5, and the sixth lens group G6.

[0082] The first lens group G1 consists of a cemented lens of a concave meniscus lens L1 with a convex surface facing the object side and a convex meniscus lens L2 with a convex surface facing the object side. The second lens group G2 consists of a concave meniscus lens L3 with a convex surface facing the object side and an aspherical R1 surface, a cemented lens of a biconcave lens L4 and a biconvex lens L5, and a concave meniscus lens L6 with a convex surface facing the image side. The third lens group G3 consists of a biconvex lens L7 with both R1 and R2 surfaces being aspherical, a cemented lens of a biconcave lens L8 and a convex meniscus lens L9 with a convex surface facing the object side, and a biconvex lens L10 with both R1 and R2 surfaces being aspherical. The biconvex lens L10 is an anti-vibration lens group GS, and during anti-vibration, it moves including a component in a direction perpendicular to the optical axis. The fourth lens group G4 consists of a concave meniscus lens L11 with a convex surface facing the object side. The fifth lens group G5 consists of a biconcave lens L12. The sixth lens group G6 consists of a biconvex lens L13.

Embodiment

[0083] FIG. 49 is a lens configuration diagram of the imaging optical system according to Embodiment 4 of the present invention.

[0084] The imaging optical system of Embodiment 4 includes a first lens group G1 having a positive refractive power, a second lens group G2 having a negative refractive power, an aperture stop, a third lens group G3 having a positive refractive power, a fourth lens group G4 having a negative refractive power, a fifth lens group G5 having a negative refractive power, and a sixth lens group G6 having a positive refractive power. When zooming from the wide-angle end to the telephoto end, the distance between the first lens group G1 and the second lens group G2 increases, the distance between the second lens group G2 and the third lens group G3 decreases, 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, the distance between the fifth lens group G5 and the sixth lens group G6 increases, the third lens group G3 and the fifth lens group G5 move along the same trajectory, and the sixth lens group G6 is fixed with respect to the image plane. The fourth lens group G4 is a focusing lens group GF, and it moves toward the image side along the optical axis during focusing from an infinite object to a close object. The rear lens group GR corresponds to the third lens group G3, the fourth lens group G4, the fifth lens group G5, and the sixth lens group G6.

[0085] The first lens group G1 consists of a concave meniscus lens L1 with a convex surface facing the object side and a convex meniscus lens L2 with a convex surface facing the object side. The second lens group G2 consists of a concave meniscus lens L3 with a convex surface facing the object side and an aspherical R1 surface, a cemented lens of a biconcave lens L4 and a biconvex lens L5, and a concave meniscus lens L6 with a convex surface facing the image side. The third lens group G3 consists of a convex meniscus lens L7 with a convex surface facing the object side and both R1 and R2 surfaces being aspherical, a cemented lens of a concave meniscus lens L8 with a convex surface facing the object side and a biconvex lens L9, and a biconvex lens L10 with both R1 and R2 surfaces being aspherical. The biconvex lens L10 is an anti-vibration lens group GS, and during anti-vibration, it moves including a component in a direction perpendicular to the optical axis. The fourth lens group G4 consists of a concave meniscus lens L11 with a convex surface facing the object side. The fifth lens group G5 consists of a concave meniscus lens L12 with a convex surface facing the image side. The sixth lens group G6 consists of a convex meniscus lens L13 with a convex surface facing the image side.

Embodiment

[0086] FIG. 65 is a lens configuration diagram of the imaging optical system according to Embodiment 5 of the present invention.

[0087] The imaging optical system according to Embodiment 5 includes a first lens group G1 having a positive refractive power, a second lens group G2 having a negative refractive power, an aperture stop, a third lens group G3 having a positive refractive power, a fourth lens group G4 having a negative refractive power, a fifth lens group G5 having a negative refractive power, and a sixth lens group G6 having a positive refractive power. When zooming from the wide-angle end to the telephoto end, the distance between the first lens group G1 and the second lens group G2 increases, the distance between the second lens group G2 and the third lens group G3 decreases, 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, the distance between the fifth lens group G5 and the sixth lens group G6 increases, the third lens group G3 and the fifth lens group G5 move along the same trajectory, and the sixth lens group G6 is fixed with respect to the image plane. The fourth lens group G4 is a focusing lens group GF, and during focusing from an infinite object to a close object, it moves toward the image side along the optical axis. The rear lens group GR corresponds to the third lens group G3, the fourth lens group G4, the fifth lens group G5, and the sixth lens group G6.

[0088] The first lens group G1 consists of a cemented lens of a concave meniscus lens L1 with its convex surface facing the object side and a convex meniscus lens L2 with its convex surface facing the object side. The second lens group G2 consists of a concave meniscus lens L3 with its convex surface facing the object side and an aspherical R1 surface, a cemented lens of a biconcave lens L4 and a biconvex lens L5, and a concave meniscus lens L6 with its convex surface facing the image side. The third lens group G3 consists of a biconvex lens L7 with both R1 and R2 surfaces being aspherical, a cemented lens of a biconcave lens L8 and a convex meniscus lens L9 with its convex surface facing the object side, a concave meniscus lens L10 with its convex surface facing the image side, a convex meniscus lens L11 with its convex surface facing the image side, and a biconvex lens L12 with both R1 and R2 surfaces being aspherical. The biconvex lens L12 is an anti-vibration lens group GS, and it moves including a component in a direction perpendicular to the optical axis during anti-vibration. The fourth lens group G4 consists of a concave meniscus lens L13 with its convex surface facing the object side. The fifth lens group G5 consists of a concave meniscus lens L14 with its convex surface facing the image side. The sixth lens group G6 consists of a biconvex lens L15.

Embodiment

[0089] FIG. 81 is a lens configuration diagram of the imaging optical system according to Embodiment 6 of the present invention.

[0090] The imaging optical system of Example 6 includes a first lens group G1 having a positive refractive power, a second lens group G2 having a negative refractive power, an aperture stop, a third lens group G3 having a positive refractive power, a fourth lens group G4 having a negative refractive power, a fifth lens group G5 having a negative refractive power, and a sixth lens group G6 having a positive refractive power. When zooming from the wide-angle end to the telephoto end, the distance between the first lens group G1 and the second lens group G2 increases, the distance between the second lens group G2 and the third lens group G3 decreases, 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, the distance between the fifth lens group G5 and the sixth lens group G6 increases, the third lens group G3 and the fifth lens group G5 move along the same locus, and the sixth lens group G6 is fixed with respect to the image plane. The fourth lens group G4 is a focusing lens group GF and moves toward the image plane side along the optical axis when focusing from an infinite object to a close object. The rear lens group GR corresponds to the third lens group G3, the fourth lens group G4, the fifth lens group G5, and the sixth lens group G6.

[0091] The first lens group G1 consists of a cemented lens of a concave meniscus lens L1 with a convex surface facing the object side and a convex meniscus lens L2 with a convex surface facing the object side. The second lens group G2 consists of a concave meniscus lens L3 with a convex surface facing the object side and an aspherical R1 surface, a cemented lens of a biconcave lens L4 and a biconvex lens L5, and a concave meniscus lens L6 with a convex surface facing the image plane side. The third lens group G3 consists of a biconvex lens L7 with both R1 and R2 surfaces being aspherical, a biconcave lens L8, a cemented lens of a convex meniscus lens L9 with a convex surface facing the object side, and a biconvex lens L10 with both R1 and R2 surfaces being aspherical. The biconvex lens L10 is an anti-vibration lens group GS and moves including a component in a direction perpendicular to the optical axis during anti-vibration. The fourth lens group G4 consists of a concave meniscus lens L11 with a convex surface facing the object side. The fifth lens group G5 consists of a concave meniscus lens L12 with a convex surface facing the image plane side. The sixth lens group G6 consists of a convex meniscus lens L13 with a convex surface facing the image plane side.

Example

[0092] FIG. 97 is a lens configuration diagram of the imaging optical system of Example 7 of the present invention.

[0093] The imaging optical system of Example 7 includes a first lens group G1 having a positive refractive power, a second lens group G2 having a negative refractive power, an aperture stop, a third lens group G3 having a positive refractive power, a fourth lens group G4 having a negative refractive power, a fifth lens group G5 having a negative refractive power, and a sixth lens group G6 having a positive refractive power. When zooming from the wide-angle end to the telephoto end, the distance between the first lens group G1 and the second lens group G2 increases, the distance between the second lens group G2 and the third lens group G3 decreases, 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, the distance between the fifth lens group G5 and the sixth lens group G6 increases, the third lens group G3 and the fifth lens group G5 move along the same locus, and the sixth lens group G6 is fixed with respect to the image plane. The fourth lens group G4 is a focusing lens group GF and moves toward the image plane side along the optical axis when focusing from an infinite object to a close object. The rear lens group GR corresponds to the third lens group G3, the fourth lens group G4, the fifth lens group G5, and the sixth lens group G6.

[0094] The first lens group G1 consists of a cemented lens of a concave meniscus lens L1 with a convex surface facing the object side and a convex meniscus lens L2 with a convex surface facing the object side. The second lens group G2 consists of a concave meniscus lens L3 with a convex surface facing the object side and an aspherical R1 surface, a cemented lens of a biconcave lens L4 and a biconvex lens L5, and a concave meniscus lens L6 with a convex surface facing the image plane side. The third lens group G3 consists of a biconvex lens L7 with both R1 and R2 surfaces being aspherical, a biconcave lens L8, a cemented lens of a convex meniscus lens L9 with a convex surface facing the object side, and a biconvex lens L10 with both R1 and R2 surfaces being aspherical. The biconvex lens L10 is an anti-vibration lens group GS and moves including a component in a direction perpendicular to the optical axis during anti-vibration. The fourth lens group G4 consists of a concave meniscus lens L11 with a convex surface facing the object side. The fifth lens group G5 consists of a concave meniscus lens L12 with a convex surface facing the image plane side. The sixth lens group G6 consists of a convex meniscus lens L13 with a convex surface facing the image plane side.

Example

[0095] FIG. 113 is a lens configuration diagram of the imaging optical system of Example 8 of the present invention.

[0096] The imaging optical system of Example 8 includes a first lens group G1 having a positive refractive power, a second lens group G2 having a negative refractive power, an aperture stop, a third lens group G3 having a positive refractive power, a fourth lens group G4 having a negative refractive power, a fifth lens group G5 having a negative refractive power, and a sixth lens group G6 having a positive refractive power. When zooming from the wide-angle end to the telephoto end, the distance between the first lens group G1 and the second lens group G2 increases, the distance between the second lens group G2 and the third lens group G3 decreases, 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, the distance between the fifth lens group G5 and the sixth lens group G6 increases, the third lens group G3 and the fifth lens group G5 move along the same locus, and the sixth lens group G6 is fixed with respect to the image plane. The fourth lens group G4 is a focusing lens group GF and moves toward the image plane side along the optical axis during focusing from an infinite object to a close object. The rear lens group GR corresponds to the third lens group G3, the fourth lens group G4, the fifth lens group G5, and the sixth lens group G6.

[0097] The first lens group G1 consists of a cemented lens of a concave meniscus lens L1 with a convex surface facing the object side and a convex meniscus lens L2 with a convex surface facing the object side. The second lens group G2 consists of a concave meniscus lens L3 with a convex surface facing the object side and an aspherical R1 surface, a cemented lens of a biconcave lens L4 and a biconvex lens L5, and a concave meniscus lens L6 with a convex surface facing the image plane side. The third lens group G3 consists of a biconvex lens L7 with both R1 and R2 surfaces being aspherical, a cemented lens of a concave meniscus lens L8 with a convex surface facing the object side and a convex meniscus lens L9 with a convex surface facing the object side, and a biconvex lens L10 with both R1 and R2 surfaces being aspherical. The biconvex lens L10 is an anti-vibration lens group GS and moves including a component in a direction perpendicular to the optical axis during anti-vibration. The fourth lens group G4 consists of a concave meniscus lens L11 with a convex surface facing the object side. The fifth lens group G5 consists of a concave meniscus lens L12 with a convex surface facing the image plane side. The sixth lens group G6 consists of a convex meniscus lens L13 with a convex surface facing the image plane side.

Example

[0098] FIG. 129 is a lens configuration diagram of the imaging optical system according to Embodiment 9 of the present invention.

[0099] The imaging optical system according to Embodiment 9 includes a first lens group G1 having a positive refractive power, a second lens group G2 having a negative refractive power, an aperture stop, a third lens group G3 having a positive refractive power, a fourth lens group G4 having a negative refractive power, a fifth lens group G5 having a negative refractive power, and a sixth lens group G6 having a positive refractive power. When zooming from the wide-angle end to the telephoto end, the distance between the first lens group G1 and the second lens group G2 increases, the distance between the second lens group G2 and the third lens group G3 decreases, 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, the distance between the fifth lens group G5 and the sixth lens group G6 increases, the third lens group G3 and the fifth lens group G5 move along the same locus, and the sixth lens group G6 is fixed with respect to the image plane. The fourth lens group G4 is a focusing lens group GF and moves toward the image plane side along the optical axis when focusing from an infinite object to a close object. The rear lens group GR corresponds to the third lens group G3, the fourth lens group G4, the fifth lens group G5, and the sixth lens group G6.

[0100] The first lens group G1 consists of a cemented lens of a concave meniscus lens L1 with a convex surface facing the object side and a convex meniscus lens L2 with a convex surface facing the object side. The second lens group G2 consists of a concave meniscus lens L3 with a convex surface facing the object side and an aspherical R1 surface, a cemented lens of a biconcave lens L4 and a biconvex lens L5, and a concave meniscus lens L6 with a convex surface facing the image plane side. The third lens group G3 consists of a biconvex lens L7 with both R1 and R2 surfaces being aspherical, a cemented lens of a concave meniscus lens L8 with a convex surface facing the object side and a convex meniscus lens L9 with a convex surface facing the object side, a cemented lens of a biconcave lens L10 and a convex meniscus lens L11 with a convex surface facing the object side, and a biconvex lens L12 with both R1 and R2 surfaces being aspherical. The biconvex lens L12 is an anti-vibration lens group GS and moves including a component in a direction perpendicular to the optical axis during anti-vibration. The fourth lens group G4 consists of a concave meniscus lens L13 with a convex surface facing the object side. The fifth lens group G5 consists of a concave meniscus lens L14 with a convex surface facing the image plane side. The sixth lens group G6 consists of a convex meniscus lens L15 with a convex surface facing the object side.

Example

[0101] FIG. 145 is a lens configuration diagram of the imaging optical system according to Embodiment 10 of the present invention.

[0102] The imaging optical system according to Embodiment 10 includes a first lens group G1 having a positive refractive power, a second lens group G2 having a negative refractive power, an aperture stop, a third lens group G3 having a positive refractive power, a fourth lens group G4 having a negative refractive power, a fifth lens group G5 having a negative refractive power, and a sixth lens group G6 having a positive refractive power. When zooming from the wide-angle end to the telephoto end, the distance between the first lens group G1 and the second lens group G2 increases, the distance between the second lens group G2 and the third lens group G3 decreases, 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, the distance between the fifth lens group G5 and the sixth lens group G6 increases, the third lens group G3 and the fifth lens group G5 move along the same locus, and the sixth lens group G6 is fixed with respect to the image plane. The fourth lens group G4 is a focusing lens group GF and moves toward the image plane side along the optical axis during focusing from an infinite object to a near-distance object. The rear lens group GR corresponds to the third lens group G3, the fourth lens group G4, the fifth lens group G5, and the sixth lens group G6.

[0103] The first lens group G1 consists of a cemented lens of a concave meniscus lens L1 with its convex surface facing the object side and a convex meniscus lens L2 with its convex surface facing the object side. The second lens group G2 consists of a concave meniscus lens L3 with its convex surface facing the object side and both R1 and R2 surfaces being aspherical, a cemented lens of a biconcave lens L4 and a biconvex lens L5, and a concave meniscus lens L6 with its convex surface facing the image side. The third lens group G3 consists of a biconvex lens L7 with both R1 and R2 surfaces being aspherical, a cemented lens of a biconcave lens L8 and a convex meniscus lens L9 with its convex surface facing the object side, and a biconvex lens L10 with both R1 and R2 surfaces being aspherical. The biconvex lens L10 is an anti-vibration lens group GS, and it moves including a component in a direction perpendicular to the optical axis during anti-vibration. The fourth lens group G4 consists of a concave meniscus lens L11 with its convex surface facing the object side. The fifth lens group G5 consists of a concave meniscus lens L12 with its convex surface facing the image side. The sixth lens group G6 consists of a convex meniscus lens L13 with its convex surface facing the image side.

Embodiment

[0104] FIG. 161 is a lens configuration diagram of the imaging optical system according to Embodiment 11 of the present invention.

[0105] The imaging optical system of Example 11 includes a first lens group G1 having a positive refractive power, a second lens group G2 having a negative refractive power, an aperture stop, a third lens group G3 having a positive refractive power, a fourth lens group G4 having a positive refractive power, a fifth lens group G5 having a negative refractive power, and a sixth lens group G6 having a positive refractive power. When zooming from the wide-angle end to the telephoto end, the distance between the first lens group G1 and the second lens group G2 increases, the distance between the second lens group G2 and the third lens group G3 decreases, 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, the distance between the fifth lens group G5 and the sixth lens group G6 increases, the third lens group G3 and the fifth lens group G5 move along the same locus, and the sixth lens group G6 is fixed with respect to the image plane. The fourth lens group G4 is a focusing lens group GF and moves toward the object side along the optical axis when focusing from an infinite object to a close object. The fifth lens group G5 is an anti-shake lens group GS and moves including a component in a direction perpendicular to the optical axis during anti-shake. The rear lens group GR corresponds to the third lens group G3, the fourth lens group G4, the fifth lens group G5, and the sixth lens group G6.

[0106] The first lens group G1 consists of a cemented lens of a concave meniscus lens L1 with a convex surface facing the object side and a convex meniscus lens L2 with a convex surface facing the object side. The second lens group G2 consists of a concave meniscus lens L3 with a convex surface facing the object side and both aspherical surfaces of R1 and R2, a cemented lens of a biconcave lens L4 and a biconvex lens L5, and a concave meniscus lens L6 with a convex surface facing the image plane side. The third lens group G3 consists of a biconvex lens L7 with both aspherical surfaces of R1 and R2, a cemented lens of a concave meniscus lens L8 with a convex surface facing the object side and a convex meniscus lens L9 with a convex surface facing the object side, and a cemented lens of a biconcave lens L10 and a biconvex lens L11. The fourth lens group G4 consists of a biconvex lens L12 with both aspherical surfaces of R1 and R2. The fifth lens group G5 consists of a concave meniscus lens L13 with a convex surface facing the object side. The sixth lens group G6 consists of a biconvex lens L14.

[0107] The following shows the specific numerical data of each example of the imaging optical system of the present invention described above.

[0108] In [Surface Data], the surface number is the number of the lens surface or aperture stop counted from the object side, r is the radius of curvature of each surface, d is the distance between each surface, nd is the refractive index with respect to the d-line (wavelength 587.56 nm), and vd is the Abbe number with respect to the d-line.

[0109] An asterisk (*) attached to the surface number indicates that the shape of the lens surface is aspherical. Also, BF represents the back focus.

[0110] A diaphragm () attached to the surface number indicates that the aperture stop is located at that position. Infinity (∞) is entered for the radius of curvature with respect to a plane or an aperture stop.

[0111] [Aspherical Data] shows the values of the coefficients that give the aspherical shape of the lens surface marked with an asterisk in [Surface Data]. The shape of the aspherical surface is such that when the displacement from the optical axis in the direction perpendicular to the optical axis is y, the displacement in the optical axis direction from the intersection of the aspherical surface and the optical axis (sag amount) is z, the radius of curvature of the reference sphere is r, the conic coefficient is K, and the aspherical coefficients of the 4th to **th order are A4, A6, ···, A16 respectively, the coordinates of the aspherical surface are represented by the following formula.

[0112] TIFF0007689714000001.tif19137

[0113] [Various Data] shows values such as the zoom ratio and the focal length in each focal length state.

[0114] [Variable Interval Data] shows the values of the variable interval and BF in each focal length state.

[0115] [Lens Group Data] shows the surface number of the most object-side surface that constitutes each lens group and the combined focal length of the entire group.

[0116] In addition, for all the following specification values, the units of the described focal length f, radius of curvature r, lens surface interval d, and other lengths are millimeters (mm) unless otherwise specified. However, in the optical system, the same optical performance can be obtained in both proportional magnification and proportional reduction, so it is not limited to this.

[0117] In addition, a list of corresponding values of the conditional expressions in each of these examples is shown.

[0118] Also, in the aberration diagrams corresponding to each example, d, g, and C represent the d-line, g-line, and C-line respectively, and △S and △M represent the sagittal image plane and the meridional image plane respectively.

[0119] Numerical Example 1 Unit: mm [Surface Data] Surface Number r d nd vd PgF Object Surface ∞ (d0) 1 42.4041 0.9000 1.94594 17.98 0.6546 2 31.9285 6.7226 1.80420 46.50 0.5573 3 222.8493 (d3) 4* 108.9547 1.3340 1.80610 40.73 0.5694 5 13.0391 5.4197 6 -30.0939 1.8955 1.61340 44.27 0.5633 7 17.2404 3.7808 1.92119 23.96 0.6202 8 -100.0838 2.5950 9 -16.3540 0.9000 1.87070 40.73 0.5682 10 -24.6204 (d10) 11 (Aperture) ∞ 1.2000 12* 19.8492 5.4945 1.77250 49.50 0.5519 13* -60.0349 0.3826 14 -366.2956 1.8682 1.77047 29.74 0.5951 15 14.2993 3.4620 1.49700 81.61 0.5389 16 34.2759 3.1228 17* 24.2253 5.1628 1.59271 66.97 0.5367 18* -22.4374 (d18) 19 61.8773 0.9000 1.74330 49.22 0.5495 20 21.4587 (d20) 21 -256.7002 0.8000 1.62004 36.30 0.5873 22 237.6414 (d22) 23 326.6251 3.2840 1.72916 54.67 0.5453 24 -58.3586 (BF) Image plane ∞ [Aspherical data] Surface 4, Surface 12, Surface 13, Surface 17, Surface 18 K 0.0000 0.0000 0.0000 0.0000 0.0000 A4 1.55138E-05 -1.83238E-05 1.19464E-05 -2.39839E-05 3.08287E-05 A6 -1.04404E-07 -8.34593E-09 -1.73604E-08 1.85323E-08 -1.24805E-08 A8 1.57103E-09 -9.45349E-11 3.97624E-09 7.05415E-09 -1.48225E-09 A10 -1.42124E-11 -4.14960E-11 -2.39721E-10 -1.30039E-10 2.62402E-10 A12 7.07326E-14 5.82724E-13 4.39804E-12 7.94872E-13 -7.00142E-12 A14 -1.39865E-16 -3.69214E-15 -3.87616E-14 8.64117E-15 8.43479E-14 A16 0.00000E+00 0.00000E+00 1.26022E-16 -8.15382E-17 -3.71725E-16 [Various data] Zoom ratio 2.61 Wide angle Medium Telephoto Focal length 18.60 30.00 48.50 F-number 2.92 2.92 2.92 Full picture angle 2ω 79.04 49.46 31.24 Image height Y 14.20 14.20 14.20 Overall lens length 91.81 98.14 114.15 [Variable interval data] Wide angle Medium Telephoto d0 ∞ ∞ ∞ d3 1.2000 9.2981 18.0093 d10 12.5745 4.9764 1.7000 d18 1.6500 3.6748 1.9507 d20 8.7323 6.7075 8.4316 d22 0.7827 6.6120 17.1831 BF 17.6476 17.6476 17.6476 Wide angle Medium Telephoto d0 721.9425 1164.3501 1883.2288 d3 1.2000 9.2981 18.0093 d10 12.5745 4.9764 1.7000 d18 1.9867 4.1475 2.4658 d20 8.3956 6.2348 7.9166 d22 0.7827 6.6120 17.1831 BF 17.6476 17.6476 17.6476 [Lens group data] Group starting surface Focal length G1 1 68.57 G2 4 -14.63 G3 12 18.95 G4 19 -44.62 G5 21 -198.90 G6 23 68.15

[0120] Numerical example 2 Unit: mm [Surface data] Surface number r d nd vd PgF Object surface ∞ (d0) 1 38.7099 0.9000 1.94594 17.98 0.6546 2 27.7773 7.4568 1.83481 42.72 0.5647 3 179.7754 (d3) 4* 122.8167 1.3418 1.85135 40.10 0.5695 5 12.9020 5.1695 6 -31.2112 0.8000 1.61340 44.27 0.5633 7 15.6260 4.3245 1.92119 23.96 0.6202 8 -102.5099 2.3934 9 -15.6694 0.9000 1.88300 40.81 0.5656 10 -24.3331 (d10) 11 (Aperture) ∞ 1.1000 12* 18.0948 5.1486 1.77250 49.50 0.5519 13* -61.8421 0.3000 14 402.3842 0.9000 1.77047 29.74 0.5951 15 13.2883 3.3499 1.49700 81.61 0.5389 16 23.3742 3.9682 17* 19.7038 6.0680 1.59271 66.97 0.5367 18* -21.7445 (d18) 19 64.8045 0.9000 1.74330 49.22 0.5495 20 19.5913 (d20) 21 -185.5740 0.8000 1.72825 28.32 0.6059 22 308.1656 (d22) 23 308.1656 4.0958 1.61997 63.88 0.5426 24 -42.6690 (BF) Image plane ∞ [Aspherical data] Surface 4, Surface 12, Surface 13, Surface 17, Surface 18 K 0.0000 0.0000 0.0000 0.0000 0.0000 A4 1.47109E-05 -2.53421E-05 6.79565E-06 -3.88113E-05 3.61927E-05 A6 -7.08372E-08 -2.90336E-08 6.55692E-09 5.82013E-08 -7.39857E-09 A8 7.97362E-10 5.50493E-10 4.61921E-09 1.24861E-09 -4.70623E-09 A10 -5.03414E-12 -3.84489E-11 -2.21040E-10 4.28091E-11 3.10776E-10 A12 2.04962E-14 3.25848E-13 3.64982E-12 -1.24889E-12 -6.39658E-12 A14 -3.51721E-17 -2.47441E-15 -3.31914E-14 1.38691E-14 6.29811E-14 A16 0.00000E+00 0.00000E+00 1.17190E-16 -4.81520E-17 -2.34532E-16 [Various data] Zoom ratio 2.61 Wide angle Middle Telephoto Focal length 18.60 30.00 48.50 F-number 2.92 2.92 2.92 Full picture angle 2ω 79.70 49.68 31.55 Image height Y 14.20 14.20 14.20 Overall lens length 89.31 95.22 110.47 [Variable interval data] Wide angle Middle Telephoto d0 ∞ ∞ ∞ d3 1.1000 8.5574 15.3066 d10 11.6421 4.6847 1.6000 d18 1.5000 3.2600 1.7491 d20 7.4720 5.7120 7.2229 d22 0.7000 6.1169 17.6950 BF 16.9770 16.9770 16.9770 Wide angle Middle Telephoto d0 721.3487 1163.3021 1886.3109 d3 1.1000 8.5574 15.3066 d10 11.6421 4.6847 1.6000 d18 1.7933 3.6714 2.1775 d20 7.1787 5.3006 6.7945 d22 0.7000 6.1169 17.6950 BF 16.9770 16.9770 16.9770 [Lens group data] Group Starting surface Focal length G1 1 61.44 G2 4 -13.52 G3 12 17.97 G4 19 -38.10 G5 21 -158.94 G6 23 60.73

[0121] Numerical Example 3 Unit: mm [Surface Data] Surface Number r d nd vd PgF Object Surface ∞ (d0) 1 46.5648 0.9000 1.94594 17.98 0.6546 2 35.7311 6.0969 1.77250 49.63 0.5504 3 289.7975 (d3) 4* 84.0931 1.3142 1.85108 40.12 0.5685 5 13.4448 5.4605 6 -33.7847 0.8000 1.61340 44.27 0.5633 7 15.8729 4.5546 1.92119 23.96 0.6202 8 -134.9879 2.6848 9 -15.8601 0.9000 1.90043 37.37 0.5767 10 -22.7317 (d10) 11 (Aperture) ∞ 0.7000 12* 18.2080 5.3697 1.80610 40.73 0.5694 13* -68.3430 0.5222 14 -162.4046 0.9000 1.78880 28.43 0.6009 15 12.6129 3.9665 1.49700 81.61 0.5389 16 29.8567 3.3062 17* 19.4939 6.4127 1.59271 66.97 0.5367 18* -21.2236 (d18) 19 77.5014 0.9000 1.74330 49.22 0.5495 20 19.5283 (d20) 21 -127.7080 0.8000 1.51742 52.15 0.5590 22 963.7790 (d22) 23 1999.4385 3.4394 1.72916 54.67 0.5453 24 -49.1054 (BF) Image plane ∞ [Aspherical data] Surface 4, Surface 12, Surface 13, Surface 17, Surface 18 K 0.0000 0.0000 0.0000 0.0000 0.0000 A4 1.09556E-05 -1.83199E-05 7.97168E-07 -5.46727E-05 2.75178E-05 A6 -4.86675E-08 -3.90825E-08 5.14262E-08 6.30329E-08 -2.99365E-08 A8 5.36044E-10 -1.28019E-09 -1.16467E-09 9.99159E-10 -1.63126E-09 A10 -2.31014E-12 4.27345E-11 3.38823E-11 -3.07799E-11 5.07271E-11 A12 5.07917E-15 -6.84118E-13 -7.60525E-13 3.74100E-13 -4.99493E-13 A14 -3.40374E-19 2.59480E-15 3.73749E-15 -1.88342E-15 1.43682E-15 A16 0.00000E+00 0.00000E+00 0.00000E+00 0.00000E+00 0.00000E+00 [Various data] Zoom ratio 2.64 Wide-angle, Intermediate, Telephoto Focal length: 18.43, 30.00, 48.60 F-number: 2.91, 2.91, 2.91 Full picture angle 2ω: 79.11, 49.30, 31.10 Image height Y: 14.20, 14.20, 14.20 Overall lens length: 92.51, 98.96, 116.50 [Variable interval data] Wide-angle, Intermediate, Telephoto d0: ∞, ∞, ∞ d3: 1.2000, 10.1968, 20.4811 d10: 14.0492, 5.5608, 2.3000 d18: 1.5000, 3.4667, 2.2789 d20: 8.0322, 6.0655, 7.2533 d22: 0.9258, 6.8771, 17.3889 BF: 17.7700, 17.7700, 17.7700 Wide-angle, Intermediate, Telephoto d0: 715.5048, 1164.1578, 1883.6933 d3: 1.2000, 10.1968, 20.4811 d10: 14.0492, 5.5608, 2.3000 d18: 1.7549, 3.8244, 2.6738 d20: 7.7773, 5.7078, 6.8584 d22: 0.9258, 6.8771, 17.3889 BF: 17.7700, 17.7700, 17.7700 [Lens group data] Group, Starting surface, Focal length G1, 1, 76.88 G2, 4, -15.45 G3, 12, 18.57 G4, 19, -35.36 G5, 21, -217.88 G6 23 65.78

[0122] Numerical Example 4 Unit: mm [Surface Data] Surface Number r d nd vd PgF Object Surface ∞ (d0) 1 43.4100 0.9000 1.86966 20.02 0.6435 2 32.4307 0.6328 3 33.8907 6.5282 1.72916 54.67 0.5453 4 580.3566 (d4) 5* 207.9330 1.3181 1.80610 40.73 0.5694 6 13.5717 4.8232 7 -35.7070 0.8000 1.71300 53.94 0.5442 8 15.7972 4.4839 2.00100 29.13 0.5995 9 -70.4523 2.1559 10 -16.9410 0.9000 1.87070 40.73 0.5682 11 -29.2149 (d11) 12 (Diaphragm) ∞ 0.8874 13* 22.1365 4.9114 1.77250 49.50 0.5519 14* 232.1269 1.9942 15 389.4081 2.2175 1.77047 29.74 0.5951 16 17.4722 4.2155 1.49700 81.61 0.5389 17 -599.1015 2.1886 18* 19.9534 5.4749 1.59271 66.97 0.5367 19* -22.3009 (d19) 20 47.4022 0.9000 1.77250 49.63 0.5504 21 16.6455 (d21) 22 -24.4824 0.8000 1.69895 30.05 0.6029 23 -34.7615 (d23) 24 -601.7493 3.4696 1.72916 54.67 0.5453 25 -43.4690 (BF) Image plane ∞ [Aspherical data] Surface 5, 13, 14, 18, 19 K 0.0000 0.0000 0.0000 0.0000 0.0000 A4 1.34100E-05 -1.22802E-05 5.58308E-06 -3.81779E-05 3.59404E-05 A6 -5.46748E-08 -2.89981E-09 -4.29555E-09 7.63292E-09 -7.29156E-08 A8 9.80885E-10 -9.46761E-10 1.56662E-09 2.14471E-09 2.25395E-09 A10 -9.08454E-12 -2.20701E-13 -6.83314E-11 -2.61470E-11 -2.20867E-11 A12 4.51659E-14 -1.83799E-13 4.66831E-13 1.81132E-13 2.03146E-13 A14 -8.75546E-17 1.14926E-15 -1.13843E-15 3.89340E-16 4.88692E-17 A16 0.00000E+00 0.00000E+00 0.00000E+00 0.00000E+00 0.00000E+00 [Various data] Zoom ratio 2.64 Wide angle, Medium, Telephoto Focal length 18.43, 30.00, 48.60 F-number 2.91, 2.91, 2.91 Full picture angle 2ω 80.48 50.11 31.10 Image height Y 14.20 14.20 14.20 Overall lens length 93.51 99.59 114.42 [Variable interval data] Wide angle Middle Telephoto d0 ∞ ∞ ∞ d4 1.1000 8.0498 20.1119 d11 13.5610 5.2304 1.6000 d19 1.5000 3.1046 2.9353 d21 10.0927 8.4882 8.6574 d23 0.7000 8.1692 14.5681 BF 16.9500 16.9500 16.9500 Wide angle Middle Telephoto d0 714.6167 1167.9033 1882.8604 d4 1.1000 8.0498 20.1119 d11 13.5610 5.2304 1.6000 d19 1.7117 3.3795 3.2912 d21 9.8811 8.2132 8.3015 d23 0.7000 8.1692 14.5681 BF 16.9500 16.9500 16.9500 [Lens group data] Group Starting surface Focal length G1 1 73.03 G2 5 -14.82 G3 13 17.63 G4 20 -33.64 G5 22 -122.37 G6 24 64.09

[0123] Numerical example 5 Unit: mm [Surface data] Surface number r d nd vd PgF Object surface ∞ (d0) 1 42.7613 1.0000 1.84666 23.78 0.6192 2 28.3716 7.1064 1.77250 49.63 0.5504 3 207.0596 (d3) 4* 126.7118 1.1935 1.80834 40.92 0.5686 5 12.0127 5.1318 6 -24.6490 0.8000 1.60342 38.01 0.5828 7 16.6349 3.8669 1.92119 23.96 0.6202 8 -51.8156 2.1955 9 -15.3504 0.8000 1.90043 37.37 0.5767 10 -22.0583 (d10) 11 (Diaphragm) ∞ 1.0000 12* 15.1373 5.0229 1.80610 40.73 0.5694 13* -78.3037 0.1500 14 -2724.7673 0.8000 1.91082 35.25 0.5822 15 9.5419 4.2273 1.59282 68.62 0.5440 16 59.3243 2.8007 17 -14.5033 0.8000 1.77047 29.74 0.5951 18 -20.4247 0.1500 19 -50.1254 2.6915 1.59282 68.62 0.5440 20 -17.0854 0.3000 21* 24.0310 3.8640 1.59201 67.02 0.5358 22* -38.9163 (d22) 23 54.2639 0.8000 1.77250 49.63 0.5504 24 18.0643 (d24) 25 -47.6946 0.8000 1.85451 25.15 0.6103 26 -92.5624 (d26) 27 115.5641 3.2861 1.83481 42.72 0.5647 28 -78.2968 (BF) Image plane ∞ [Aspherical data] Surface 4, Surface 12, Surface 13, Surface 21, Surface 22 K 0.0000 0.0000 0.0000 0.0000 0.0000 A4 2.45639E-05 -1.04130E-05 3.50387E-05 -4.02921E-06 2.48979E-05 A6 -9.13609E-08 9.12741E-08 -4.47768E-08 -3.43621E-07 -3.56903E-07 A8 9.69870E-10 -1.21273E-09 7.82874E-10 6.79289E-09 5.55995E-09 A10 -5.58581E-12 1.47600E-11 -1.71711E-11 -8.36158E-11 -6.13618E-11 A12 1.71809E-14 -9.71183E-14 5.71635E-14 3.66285E-13 2.29766E-13 A14 0.00000E+00 0.00000E+00 0.00000E+00 0.00000E+00 0.00000E+00 A16 0.00000E+00 0.00000E+00 0.00000E+00 0.00000E+00 0.00000E+00 [Various data] Zoom ratio 2.63 Wide angle, Medium, Telephoto Focal length 18.45 29.93 48.55 F number 2.91 2.91 2.91 Full picture angle 2ω 78.31 49.45 31.13 Image height Y 14.20 14.20 14.20 Overall lens length 90.42 97.86 113.92 [Variable interval data] Wide angle Middle Telephoto d0 ∞ ∞ ∞ d3 1.2000 10.6954 20.7097 d10 12.3120 4.6364 1.3275 d22 1.5000 3.1929 2.2863 d24 7.9458 6.2529 7.1594 d26 1.2000 6.8234 16.1698 BF 17.4771 17.4771 17.4771 Wide angle Middle Telephoto d0 717.1439 1159.5500 1878.5881 d3 1.2000 10.6954 20.7097 d10 12.3120 4.6364 1.3275 d22 1.7518 3.5466 2.6926 d24 7.6939 5.8992 6.7532 d26 1.2000 6.8234 16.1698 BF 17.4771 17.4771 17.4771 [Lens group data] Group Starting surface Focal length G1 1 72.57 G2 4 -15.11 G3 12 18.25 G4 23 -35.39 G5 25 -116.10 G6 27 56.34

[0124] Numerical Example 6 Unit: mm [Surface Data] Surface Number r d nd vd PgF Object Surface ∞ (d0) 1 40.9106 0.9000 1.94594 17.98 0.6546 2 32.5085 6.3473 1.72916 54.67 0.5453 3 238.6818 (d3) 4* 68.2047 1.2354 1.85108 40.12 0.5685 5 12.7563 4.9932 6 -36.4994 0.9544 1.65412 39.68 0.5737 7 13.9645 4.2330 1.92119 23.96 0.6202 8 -155.6530 2.1375 9 -15.1681 0.9000 1.88300 40.81 0.5656 10 -22.5605 (d10) 11 (Aperture) ∞ 0.7000 12* 18.4908 4.1322 1.80610 40.73 0.5694 13* -43.8045 0.6117 14 -88.7294 0.9000 1.78880 28.43 0.6009 15 13.4237 2.2783 1.49700 81.61 0.5389 16 28.1058 2.0004 17* 24.9939 6.7279 1.59271 66.97 0.5367 18* -15.9379 (d18) 19 53.7143 0.9000 1.74330 49.22 0.5495 20 19.0461 (d20) 21 -66.2055 0.8000 1.72342 37.99 0.5820 22 -673.6734 (d22) 23 -673.6734 3.2218 1.72916 54.67 0.5453 24 -47.8641 (BF) Image plane ∞ [Aspherical data] Surface 4, Surface 12, Surface 13, Surface 17, Surface 18 K 0.0000 0.0000 0.0000 0.0000 0.0000 A4 7.51456E-06 -3.53436E-05 -4.92927E-06 -7.92987E-05 2.16492E-05 A6 -5.22798E-08 -8.36824E-08 8.54305E-08 2.12265E-07 -2.54911E-08 A8 1.13546E-09 -2.96526E-08 -3.91809E-08 -2.78117E-08 -1.47062E-08 A10 -9.22403E-12 1.12610E-09 1.49017E-09 1.06611E-09 4.93766E-10 A12 3.93488E-14 -2.50805E-11 -3.32080E-11 -2.10093E-11 -8.16624E-12 A14 -5.57775E-17 1.73706E-13 2.48746E-13 1.48680E-13 4.67402E-14 A16 0.00000E+00 0.00000E+00 0.00000E+00 0.00000E+00 0.00000E+00 [Various data] Zoom ratio 2.90 Wide angle, Medium, Telephoto Focal length 18.43, 29.97, 53.40 F-number 2.91, 3.24, 4.00 Full picture angle 2ω 80.50, 49.48, 28.42 Image height Y 14.20, 14.20, 14.20 Overall lens length 85.00 90.07 110.00 [Variable interval data] Wide angle Medium Telephoto d0 ∞ ∞ ∞ d3 1.1000 9.5769 21.3188 d10 12.5981 4.6212 1.5000 d18 1.5000 4.1322 2.2053 d20 8.6948 6.0626 7.9895 d22 0.7000 5.2650 16.5750 BF 16.4386 16.4386 16.4386 Wide angle Medium Telephoto d0 716.6458 1164.4161 2074.3623 d3 1.1000 9.5769 21.3188 d10 12.5981 4.6212 1.5000 d18 1.7704 4.5389 2.6465 d20 8.4243 5.6559 7.5483 d22 0.7000 5.2650 16.5750 BF 16.4386 16.4386 16.4386 [Lens group data] Group Starting surface Focal length G1 1 73.06 G2 4 -14.44 G3 12 16.74 G4 19 -40.15 G5 21 -101.55 G6 23 70.51

[0125] Numerical example 7 Unit: mm [Surface data] Surface number r d nd vd PgF Object surface ∞ (d0) 1 45.0587 0.9000 1.94594 17.98 0.6546 2 34.2015 6.2370 1.77250 49.63 0.5504 3 335.3946 (d3) 4* 164.9172 1.3419 1.85108 40.12 0.5685 5 12.5924 5.2058 6 -26.9164 1.0336 1.61340 44.27 0.5633 7 15.5763 4.1894 1.92119 23.96 0.6202 8 -65.2765 2.2680 9 -15.6955 0.9000 1.90366 31.32 0.5948 10 -23.9531 (d10) 11 (Aperture) ∞ 0.7000 12* 20.5700 6.6201 1.80610 40.73 0.5694 13* -43.9573 0.4521 14 -96.7320 0.9000 1.78880 28.43 0.6009 15 13.4697 3.5547 1.49700 81.61 0.5389 16 45.4566 3.4380 17* 18.7696 5.1297 1.59271 66.97 0.5367 18* -18.1920 (d18) 19 44.6598 0.9000 1.74330 49.22 0.5495 20 16.0741 (d20) 21 -50.0564 0.8000 1.63980 34.46 0.5922 22 -326.8622 (d22) 23 -326.8622 3.9479 1.71300 53.94 0.5442 24 -35.8637 (BF) Image plane ∞ [Aspherical data] Surface 4, 12, 13, 17, 18 K 0.0000 0.0000 0.0000 0.0000 0.0000 A4 1.79255E-05 -3.31671E-05 -4.71774E-06 -5.55551E-05 5.03028E-05 A6 -8.33196E-08 -4.56723E-08 -7.79680E-09 1.04802E-07 -4.60324E-08 A8 8.84215E-10 -4.48987E-09 -2.87659E-09 -2.44960E-09 -4.40088E-09 A10 -6.02608E-12 3.75379E-11 -2.86739E-11 1.42128E-10 2.33034E-10 A12 2.82558E-14 -2.09838E-13 5.21513E-13 -2.46080E-12 -3.66978E-12 A14 -6.29490E-17 -2.40131E-15 -4.20155E-15 1.77886E-14 2.37909E-14 A16 0.00000E+00 0.00000E+00 0.00000E+00 0.00000E+00 0.00000E+00 [Various data] Zoom ratio 2.39 Wide angle, Medium, Telephoto Focal length 16.30, 26.60, 38.99 F-number 2.91, 2.91, 2.91 Full picture angle 2ω 87.23, 54.82, 38.26 Image height Y 14.20, 14.20, 14.20 Overall lens length 85.01, 92.49, 106.84 [Variable interval data] Wide angle, Medium, Telephoto d0 ∞ ∞ ∞ d3 1.1000 8.7539 16.7477 d10 10.5289 3.3750 1.5000 d18 1.5000 2.8910 1.8780 d20 6.6578 5.2668 6.2799 d22 0.7000 7.6877 15.9127 BF 16.0000 16.0000 16.0000 Wide-angle, Medium, Telephoto d0 632.2673 1032.0634 1508.5486 d3 1.1000 8.7539 16.7477 d10 10.5289 3.3750 1.5000 d18 1.7269 3.1831 2.1811 d20 6.4309 4.9748 5.9768 d22 0.7000 7.6877 15.9127 BF 16.0000 16.0000 16.0000 [Lens Group Data] Group, Starting Surface, Focal Length G1 1 72.36 G2 4 -13.65 G3 12 16.61 G4 19 -34.25 G5 21 -92.49 G6 23 56.18

[0126] Numerical Example 8 Unit: mm [Surface Data] Surface Number, r, d, nd, vd, PgF Object Surface ∞ (d0) 1 47.3193 0.9000 1.94594 17.98 0.6546 2 32.9545 5.9764 1.83481 42.72 0.5647 3 292.4944 (d3) 4 * 78.8083 1.5002 1.85135 40.10 0.5695 5 12.6302 4.9783 6 -32.0456 0.8000 1.61772 49.81 0.5603 7 15.8713 3.7025 2.00069 25.46 0.6136 8 -182.2260 2.1160 9 -15.6736 0.9000 1.88300 40.81 0.5656 10 -25.2274 (d10) 11 (Diaphragm) ∞ 1.2435 12 * 14.5899 3.4404 1.76450 49.09 0.5528 13 * -80.6288 0.6467 14 201.4155 0.9000 1.77047 29.74 0.5951 15 11.7218 2.0475 1.49700 81.61 0.5389 16 17.4576 3.3173 17 * 19.0871 3.8521 1.59271 66.97 0.5367 18 * -19.5405 (d18) 19 54.6628 0.9000 1.74330 49.22 0.5495 20 18.1271 (d20) 21 -97.6591 0.8000 1.68960 31.14 0.6031 22 -1407.9599 (d22) 23 -1407.9599 3.9263 1.59349 67.00 0.5366 24 -38.9570 (BF) Image plane ∞ [Aspherical data] Surface 4, Surface 12, Surface 13, Surface 17, Surface 18 K 0.0000 0.0000 0.0000 0.0000 0.0000 A4 1.09444E-05 -1.84356E-05 4.56496E-05 -1.68807E-05 6.52329E-05 A6 -6.69600E-08 -1.35031E-07 -1.63343E-07 1.21303E-07 1.31835E-07 A8 1.34781E-09 -1.65708E-08 -1.04944E-08 2.07191E-08 4.19673E-09 A10 -1.43692E-11 1.35463E-09 2.44899E-10 -8.32610E-10 4.72454E-10 A12 8.46626E-14 -4.36325E-11 1.42345E-11 2.86110E-11 -1.24750E-11 A14 -1.90066E-16 4.33331E-13 -9.97512E-13 -5.02824E-13 1.39908E-13 A16 0.00000E+00 0.00000E+00 1.36724E-14 4.42223E-15 4.28251E-16 [Various data] Zoom ratio 2.78 Wide angle Medium Telephoto Focal length 17.45 30.00 48.50 F-number 4.11 4.11 4.10 Full picture angle 2ω 83.61 49.41 31.16 Image height Y 14.20 14.20 14.20 Overall lens length 80.01 88.14 105.10 [Variable interval data] Wide angle Medium Telephoto d0 ∞ ∞ ∞ d3 1.1000 9.1535 19.3271 d10 11.7350 4.1815 1.6000 d18 1.5000 2.9328 1.5388 d20 7.0082 5.5754 6.9694 d22 0.7000 8.3288 17.6950 BF 16.0228 16.0228 16.0228 Wide-angle Middle Telephoto d0 678.2172 1168.5611 1886.6521 d3 1.1000 9.1535 19.3271 d10 11.7350 4.1815 1.6000 d18 1.7673 3.2889 1.9332 d20 6.7409 5.2193 6.5750 d22 0.7000 8.3288 17.6950 BF 16.0228 16.0228 16.0228 [Lens group data] Group Starting surface Focal length G1 1 71.55 G2 4 -14.12 G3 12 16.10 G4 19 -36.87 G5 21 -152.21 G6 23 67.44

[0127] Numerical Example 9 Unit: mm [Surface data] Surface number r d nd vd PgF Object surface ∞ (d0) 1 68.3850 1.0000 1.86966 20.02 0.6435 2 48.1024 6.1633 1.77250 49.63 0.5504 3 680.1174 (d3) 4* 68.2033 1.1801 1.80834 40.92 0.5686 5 17.0141 7.2775 6 -35.0918 1.3688 1.65100 56.24 0.5420 7 21.0420 5.0717 1.90366 31.32 0.5948 8 -61.2061 2.9974 9 -19.2183 0.8000 1.80420 46.50 0.5573 10 -30.3720 (d10) 11 (Aperture) ∞ 1.0000 12* 37.6860 3.0587 1.69350 53.20 0.5467 13* -2438.4624 1.8851 14 17.2305 2.0825 1.80610 33.27 0.5884 15 11.8961 5.6910 1.49700 81.61 0.5389 16 20.8384 2.8749 17 -180.6181 0.8000 1.80518 25.46 0.6157 18 51.9360 1.9468 1.59410 60.47 0.5552 19 264.1760 6.2729 20* 22.0907 6.5757 1.59201 67.02 0.5358 21* -29.3796 (d21) 22 38.5734 1.6098 1.77250 49.63 0.5504 23 19.6167 (d23) 24 -52.2008 0.8000 1.74330 49.22 0.5495 25 -335.5406 (d25) 26 36.0191 3.1092 1.72916 54.67 0.5453 27 85.1538 (BF) Image plane ∞ [Aspherical data] Surface 4, Surface 12, Surface 13, Surface 20, Surface 21 K 0.0000 0.0000 0.0000 0.0000 0.0000 A4 8.08447E-06 -1.99450E-07 4.22345E-06 -2.57460E-05 1.58700E-05 A6 -6.17604E-09 1.48957E-07 1.46438E-07 -4.48514E-08 -7.04011E-08 A8 1.28195E-10 -1.16599E-09 -1.02202E-09 5.44365E-10 6.84669E-10 A10 -5.05057E-13 8.63302E-12 7.89701E-12 -4.13181E-12 -4.77526E-12 A12 1.38114E-15 -2.99096E-14 -3.03193E-14 8.33713E-15 1.02190E-14 A14 0.00000E+00 0.00000E+00 0.00000E+00 0.00000E+00 0.00000E+00 A16 0.00000E+00 0.00000E+00 0.00000E+00 0.00000E+00 0.00000E+00 [Various data] Zoom ratio 2.90 Wide angle Middle Telephoto Focal length 23.45 39.96 68.00 F number 2.91 2.91 2.91 Full picture angle 2ω 63.77 37.75 22.74 Image height Y 14.20 14.20 14.20 Overall lens length 115.01 129.53 144.79 [Variable interval data] Wide angle Middle Telephoto d0 ∞ ∞ ∞ d3 1.2000 18.9606 30.3005 d10 20.1294 9.6598 1.0000 d21 1.5000 2.2789 2.2460 d23 10.6051 9.8263 9.8591 d25 1.2000 8.4324 21.0131 BF 16.8071 16.8071 16.8071 Wide angle, Medium, Telephoto d0 909.3184 1534.9113 2632.3270 d3 1.2000 18.9606 30.3005 d10 20.1294 9.6598 1.0000 d21 1.9150 2.8309 2.8701 d23 10.1902 9.2742 9.2350 d25 1.2000 8.4324 21.0131 BF 16.8071 16.8071 16.8071 [Lens group data] Group, Starting surface, Focal length G1 1 103.89 G2 4 -22.85 G3 12 26.55 G4 22 -53.66 G5 24 -83.27 G6 26 83.39

[0128] Numerical Example 10 Unit: mm [Surface data] Surface number, r, d, nd, vd, PgF Object surface ∞ (d0) 1 72.5450 0.9000 1.92119 23.96 0.6202 2 44.3709 10.2066 1.80420 46.50 0.5573 3 564.1764 (d3) 4* 109.9354 1.2547 1.76802 49.24 0.5516 5* 21.8194 8.2519 6 -37.9444 2.7527 1.61340 44.27 0.5633 7 30.5441 5.6302 1.92119 23.96 0.6202 8 -167.8832 3.2605 9 -24.2469 1.8929 1.88300 40.81 0.5656 10 -36.7191 (d10) 11(Diaphragm) ∞ 1.2000 12* 30.3692 8.6351 1.77250 49.46 0.5539 13* -73.2042 0.3000 14 -545.3813 1.9918 1.77047 29.74 0.5951 15 22.8002 9.2574 1.49700 81.61 0.5389 16 39.9538 4.6338 17* 26.6904 8.9325 1.59271 66.97 0.5367 18* -35.3661 (d18) 19 56.3961 1.4906 1.74330 49.22 0.5495 20 24.6219 (d20) 21 -40.0095 0.8000 1.77047 29.74 0.5951 22 -61.5572 (d22) 23 -222.3949 3.5658 1.72916 54.67 0.5453 24 -58.9876 (BF) Image plane ∞ [Aspherical data] Surface 4, Surface 5, Surface 12 K 0.0000 0.0000 0.0000 A4 4.47410E-06 1.05434E-06 -8.83945E-06 A6 3.04043E-08 5.50469E-08 1.98321E-09 A8 -2.97646E-10 -3.86316E-10 -2.21611E-10 A10 1.50325E-12 1.38347E-12 2.72965E-13 A12 -3.51504E-15 0.00000E+00 3.20189E-15 A14 3.33552E-18 0.00000E+00 -2.41573E-17 A16 0.00000E+00 0.00000E+00 0.00000E+00 Surfaces 13, 17, 18 K 0.0000 0.0000 0.0000 A4 -9.75754E-07 -1.08381E-05 1.20429E-05 A6 3.10826E-09 2.26793E-09 -7.41889E-09 A8 -1.19123E-10 1.85468E-10 1.05883E-10 A10 -2.08756E-12 8.70142E-13 3.61538E-12 A12 2.52768E-14 -1.46025E-14 -3.76078E-14 A14 -1.29845E-16 7.67060E-17 1.60011E-16 A16 2.15945E-19 -7.86897E-20 -1.51918E-19 [Various data] Zoom ratio 2.55 Wide angle, Medium, Telephoto Focal length 28.50, 45.00, 72.80 F-number 2.92, 2.92, 2.92 Full picture angle 2ω 79.08, 50.25, 31.60 Image height Y 21.63, 21.63, 21.63 Overall lens length 135.24, 145.97, 165.37 [Variable interval data] Wide angle, Medium, Telephoto d0 ∞ ∞ ∞ d3 1.1000 14.0555 29.1370 d10 19.0721 8.3778 1.7000 d18 1.5000 3.5415 3.5473 d20 15.2839 13.2424 13.2366 d22 0.7000 9.1682 20.1606 BF 22.6296 22.6296 22.6296 Wide angle, Medium, Telephoto d0 1105.9598 1745.9645 2820.8243 d3 1.1000 14.0555 29.1370 d10 19.0721 8.3778 1.7000 d18 1.9256 4.0951 4.2201 d20 14.8584 12.6888 12.5638 d22 0.7000 9.1682 20.1606 BF 22.6296 22.6296 22.6296 [Lens group data] Group, Starting surface, Focal length G1 1 114.40 G2 4 -22.99 G3 12 27.61 G4 19 -59.99 G5 21 -150.79 G6 23 109.10

[0129] Numerical Example 11 Unit: mm [Surface data] Surface number, r, d, nd, vd, PgF Object surface ∞ (d0) 1 38.0857 1.0000 1.80809 22.76 0.6287 2 27.4246 6.3831 1.72916 54.67 0.5453 3 194.6484 (d3) 4 * 69.8716 1.1721 1.80834 40.92 0.5686 5 12.0574 5.4022 6 -26.3242 1.0073 1.70154 41.15 0.5770 7 16.3988 4.0708 2.00069 25.46 0.6136 8 -56.4419 2.1190 9 -15.6041 0.8000 1.90043 37.37 0.5767 10 -24.9569 (d10) 11 (Aperture) ∞ 0.9663 12 * 29.6609 2.8717 1.76802 49.24 0.5516 13 * -92.1828 0.5000 14 17.4344 1.1880 1.73037 32.23 0.5899 15 10.8271 2.9535 1.55032 75.50 0.5401 16 16.1215 2.5920 17 -122.8295 0.8000 1.85451 25.15 0.6103 18 54.1065 2.7130 1.59282 68.62 0.5440 19 -41.2347 (d19) 20 * 27.6453 4.5453 1.59201 67.02 0.5358 21 * -31.2090 (d21) 22 236.9888 0.8000 1.74330 49.22 0.5495 23 21.5280 (d23) 24 53.8093 5.2286 1.48749 70.44 0.5306 25 -56.2838 (BF) Image plane ∞ [Aspherical data] Surfaces 4, 12, 13, 20, 21 K 0.0000 0.0000 0.0000 0.0000 0.0000 A4 1.45836E-05 5.37165E-06 2.14026E-05 -1.38031E-05 1.11833E-05 A6 7.95635E-09 -1.20066E-07 -1.50610E-07 3.37316E-08 5.75401E-08 A8 -1.29993E-10 2.78394E-09 3.14625E-09 -3.63190E-10 -1.02947E-09 A10 1.36888E-12 -1.85033E-11 -2.09938E-11 1.98358E-12 5.05012E-12 A12 0.00000E+00 0.00000E+00 0.00000E+00 0.00000E+00 0.00000E+00 A14 0.00000E+00 0.00000E+00 0.00000E+00 0.00000E+00 0.00000E+00 A16 0.00000E+00 0.00000E+00 0.00000E+00 0.00000E+00 0.00000E+00 [Various data] Zoom ratio 2.62 Wide angle, Medium, Telephoto Focal length 18.53, 29.83, 48.51 F-number 2.91, 2.91, 2.91 Full picture angle 2ω 78.07, 50.44, 31.15 Image height Y 14.20, 14.20, 14.20 Total lens length 90.11, 93.86, 113.20 [Variable interval data] Wide angle, Medium, Telephoto d0 ∞ ∞ ∞ d3 0.9559, 5.9805, 18.3147 d10 11.7396 3.5262 1.3308 d19 6.5890 4.0657 5.6305 d21 2.0425 4.5657 3.0010 d23 3.3462 10.2858 19.4931 BF 18.3196 18.3196 18.3196 Wide-angle, Medium, Telephoto d0 721.2976 1171.8515 1892.1010 d3 0.9559 5.9805 18.3147 d10 11.7396 3.5262 1.3308 d19 6.3394 3.7444 5.2160 d21 2.2920 4.8870 3.4155 d23 3.3462 10.2858 19.4931 BF 18.3196 18.3196 18.3196 [Lens group data] Group, Starting surface, Focal length G1 1 67.00 G2 4 -14.20 G3 12 30.31 G4 20 25.49 G5 22 -31.91 G6 24 57.32

[0130] [Conditional formula corresponding values] Ex1 Ex2 Ex3 Ex4 Ex5 Ex6 Ex7 Ex8 Ex9 Ex10 Ex11 (1) 2.89 2.69 3.17 3.03 3.05 3.41 3.35 3.46 3.40 3.31 2.79 (2) 18.88 18.37 18.96 19.16 18.53 23.94 17.42 23.10 23.57 18.26 18.47 (3) 3.69 3.30 4.17 3.96 3.93 3.96 4.44 4.10 4.43 4.01 3.62 (4) 4.69 4.54 4.98 4.93 4.80 5.06 5.30 5.07 4.55 4.98 4.72 (5) 1.88 1.89 1.86 1.80 1.81 1.84 1.86 1.89 1.82 1.86 1.77 (6) 29.74 29.74 28.43 29.74 35.25 28.43 28.43 29.74 33.27 29.74 32.23 (7) 0.666 0.666 0.669 0.666 0.667 0.669 0.669 0.666 0.668 0.666 0.667 (8) 0.92 0.79 0.73 0.69 0.73 0.75 0.88 0.76 0.79 0.82 0.53 (9) 1.24 1.20 1.25 1.19 1.23 1.16 1.13 1.13 1.18 1.05 1.29 (10) 1.20 1.14 1.30 1.14 1.27 1.36 1.34 1.44 1.27 1.06 1.25 (11) 1.10 0.99 0.99 1.01 1.39 0.95 1.01 0.97 0.95 0.95 1.72

Explanation of Symbols

[0131] G1 First lens group G2 Second lens group G3 Third lens group G4 Fourth lens group G5 Fifth lens group G6 Sixth lens group GR Rear lens group GF Focusing lens group GS Vibration-proof lens group S Aperture stop I Image plane

Claims

1. Comprising, 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 rear lens group GR having a positive refractive power, the rear lens group GR consists of a third lens group G3 having a positive refractive power, a fourth lens group G4 having a positive or negative refractive power, a fifth lens group G5 having a negative refractive power, and a sixth lens group G6 having a positive refractive power, from the object side, When zooming from the wide-angle end to the telephoto end, the distance between adjacent lens groups changes, and the third lens group G3 and the fifth lens group G5 move along the same locus, the first lens group G1 consists of one negative lens and one positive lens, the rear lens group GR has a negative lens, the fourth lens group G4 moves along the optical axis when focusing from an infinite object to a close object, An imaging optical system characterized by satisfying the following conditional expressions. (1) 1.80 < f1 / fRW < 5.50 (2) 12.0 < LTW × FnoT / Ymax < 30.0 (6) νdRn < 50 (7) PgFRn + 0.0024 × νdRn < 0.672 (8) 0.40 < |f4| / fT < 1.50 However, f1: Focal length of the first lens group G1 fRW: Focal length of the rear lens group GR at infinity focus at the wide-angle end LTW: Overall optical length of the imaging optical system at the wide-angle end FnoT: Aperture F-number of the imaging optical system at infinity focus at the telephoto end Ymax: Maximum image height of the imaging optical system νdRn: Abbe number with respect to the d-line of the negative lens located closest to the object side among the negative lenses of the rear lens group GR PgFRn: Partial dispersion ratio with respect to the g-line and F-line of the negative lens located closest to the object side among the negative lenses of the rear lens group GR f4: Focal length of the fourth lens group G4 fT: Focal length of the imaging optical system at infinity focus at the telephoto end

2. The lens group located closest to the image plane side of the rear lens group GR is fixed with respect to the image plane. The imaging optical system according to claim 1, characterized in that.

3. The imaging optical system according to claims 1 to 2, characterized by satisfying the following conditional expressions shown below. (3) 2.00 < f1 / fW < 6.00 However, f1: Focal length of the first lens group G1 fW: Focal length of the imaging optical system at infinity focus at the wide-angle end

4. The imaging optical system according to claims 1 to 3, characterized by satisfying the following conditional expressions shown below. (4) 4.00 < f1 / |f2| < 6.50 However, f1: Focal length of the first lens group G1 f2: Focal length of the second lens group G2

5. The imaging optical system according to claims 1 to 4, characterized by satisfying the conditional expressions shown below. (5) 1.70 < nd1ave However, nd1ave: The average value of the refractive indices with respect to the d-line of all the lenses constituting the first lens group G1

6. The imaging optical system according to claims 1 to 5, characterized by satisfying the conditional expressions shown below. (9) BFT / Ymax < 2.00 However, BFT: The back focus of the imaging optical system at the telephoto end Ymax: The maximum image height of the imaging optical system

7. The imaging optical system according to claims 1 to 6, characterized by satisfying the conditional expressions shown below. (10) 0.80 < M1 / fW < 2.00 However, M1: The movement amount in the zooming from the wide-angle end to the telephoto end of the first lens group G1 fW: The focal length of the imaging optical system at infinity focus at the wide-angle end

8. The rear lens group GR has an anti-vibration lens group GS that moves including a component in the direction perpendicular to the optical axis, and the imaging optical system according to claims 1 to 7, characterized by satisfying the conditional expressions shown below. (11) 0.50 < |fS| / fW < 4.0 However, fS: The focal length of the anti-vibration lens group GS fW: The focal length of the imaging optical system at infinity focus at the wide-angle end

Images