JP2021076830A - Zoom lens system, lens barrel having the same, image capturing device, and camera system - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a zoom lens system capable of satisfactorily correcting various aberrations in the entire zoom range, and an image pickup device and a camera system including the same. SOLUTION: A zoom lens system is composed of a first lens group having a positive power, a second lens group having a negative power, and a succeeding lens group in order from an object side to an image side. Subsequent lens groups are the first focus lens group with negative power that moves along the optical axis when focusing from the infinity focus state to the close object focus state, and the image side of the first focus lens group. A second focus lens group, which is adjacent to and has a positive power, is provided. When zooming from the wide-angle end to the telephoto end, the first lens group is fixed to the image plane, and the distance between the lens groups changes. Then, the condition (1) −0.23 <f2 / TTL <−0.15 is satisfied. Here, TTL: the total optical length at the telephoto end, and f2: the focal length of the second lens group. [Selection diagram] Fig. 1

Description

The present disclosure relates to a zoom lens system in which various aberrations in the entire zoom range are satisfactorily corrected and having high close-up photography capability, a lens barrel provided with the same, an imaging device, and a camera system.

Patent Document 1 describes, in order from the object side to the image 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 negative lens group. Discloses a zoom lens composed of a fourth lens group having an optical power of, a fifth lens group having a positive optical power, and a sixth lens group having a negative optical power. In this zoom lens, when zooming from the wide-angle end state to the telephoto end state, all the intervals between adjacent lens groups change, and the first lens group moves toward the object side with respect to the image plane.

Japanese Unexamined Patent Publication No. 2004-212612

An object of the present disclosure is to provide a zoom lens system capable of satisfactorily correcting various aberrations in the entire zoom range, and a lens barrel, an imaging device, and a camera system including the same.

The zoom lens system in the present disclosure is composed of a first lens group having a positive power, a second lens group having a negative power, and a succeeding lens group in this order from the object side to the image side. Is adjacent to the image side of the first focus lens group having negative power, which moves along the optical axis when focusing from the infinity focus state to the close object focus state, and the first focus lens group. However, it is equipped with a second focus lens group having positive power, and when zooming from the wide-angle end to the telescopic end, the first lens group is fixed to the image plane and the distance between the lens groups changes. However, the following condition (1) is satisfied,
-0.23 <f2 / TTL <-0.15 ... (1)
Here, TTL: the total optical length at the telephoto end, and f2: the focal length of the second lens group.

According to the present disclosure, it is possible to provide a zoom lens system capable of satisfactorily correcting various aberrations in the entire zoom range, and an image pickup device and a camera system including the same.

The lens arrangement diagram which shows the infinity focusing state of the zoom lens system which concerns on Embodiment 1. Numerical value of the same embodiment Longitudinal aberration diagram of the zoom lens system according to the first embodiment in the infinity focusing state FIG. 3 is a lens layout diagram showing an infinity-focused state of the zoom lens system according to the second embodiment. FIG. 4 is a longitudinal aberration diagram of the zoom lens system in the infinity-focused state according to the numerical embodiment 2 of the same embodiment. FIG. 5 is a lens layout diagram showing an infinity-focused state of the zoom lens system according to the third embodiment. FIG. 6 is a longitudinal aberration diagram of the zoom lens system in the infinity-focused state according to the numerical embodiment 3 of the same embodiment. FIG. 7 is a lens layout diagram showing an infinity-focused state of the zoom lens system according to the fourth embodiment. FIG. 8 is a longitudinal aberration diagram of the zoom lens system according to the numerical embodiment 4 of the same embodiment in the infinity in-focus state. FIG. 9 is a schematic configuration diagram of an image pickup apparatus including the zoom lens system according to the first embodiment. Schematic configuration diagram of a camera system including the room lens system according to the first embodiment.

Hereinafter, embodiments will be described in detail with reference to the drawings. However, more detailed explanation than necessary may be omitted. For example, detailed explanations of already well-known matters and duplicate explanations for substantially the same configuration may be omitted. This is to avoid unnecessary redundancy of the following description and to facilitate the understanding of those skilled in the art.

It should be noted that the accompanying drawings and the following description are provided for those skilled in the art to fully understand the present disclosure and are not intended to limit the subject matter described in the claims.

(Embodiments 1 to 4)
Hereinafter, the zoom lens system according to the first to fourth embodiments will be described individually with reference to the drawings.

The zoom lens systems of the first to third embodiments include the first lens group G1, the second lens group G2, and the third lens group G3, the fourth lens group G4, and the fifth lens group G5 that constitute the subsequent lens group. , A sixth lens group G6, and a seventh lens group G7. The zoom lens system of the fourth embodiment includes a first lens group G1, a second lens group G2, and a third lens group G3, a fourth lens group G4, a fifth lens group G5, and a sixth lens constituting the subsequent lens group. Group G6.

1, FIG. 3, FIG. 5, and FIG. 7 are lens arrangement diagrams showing a zoom lens system in an infinity in-focus state.

FIG. 1, FIG. 3, FIG. 5 and FIG. 7A show a lens arrangement diagram at a wide-angle end (shortest focal length state: focal length fW). FIG. 3D in each figure shows a lens arrangement diagram at an intermediate position (intermediate focal length state: focal length fM = √ (fW * fT)). (E) of each figure shows a lens arrangement diagram at a telephoto end (longest focal length state: focal length fT). The aspect ratios are the same in (a), (d), and (e) of each figure.

Further, the polygonal line arrows shown in (c) of each figure connect the positions of the lens groups in each state of the wide-angle end (Wide), the intermediate position (Mid), and the telephoto end (Tele) in order from the top. .. Note that the arrows simply connect the wide-angle end and the intermediate position and the intermediate position and the telephoto end with a line, and do not indicate the actual movement of each lens group.

Further, in (b) of each figure, the reference numerals of G1 to G6 or G1 to G7 are written in each lens group corresponding to the position of each lens group shown in (a).

The asterisk * attached to the surface of the specific lens element shown in (a) of each figure indicates that the surface is an aspherical surface.

Further, the symbols (+) and symbols (−) attached to the symbols of the respective lens groups (G1 to G6 or G1 to G7) shown in (b) of each figure correspond to the power of each lens group. That is, the symbol (+) indicates positive power, and the symbol (-) indicates negative power. The arrows attached to the lens groups shown in the fifth lens group G5 and the sixth lens group G6 in the first to third embodiments and the lens groups shown in the fourth lens group G4 and the fifth lens group G5 in the fourth embodiment are used. The attached arrow conveniently indicates the moving direction of the lens group during focusing from the infinity focusing state to the near junction focusing state. The specifically moving lens element, the lens group, and the moving direction thereof will be specifically described later for each embodiment.

In (a), (d), and (e) of each figure, the straight line on the far right indicates the position of the image plane S (the plane on the object side of the image sensor). Therefore, the left side of the drawing corresponds to the object side. Further, a parallel flat plate P such as a low-pass filter or a cover glass is arranged between the final lens group facing the image plane S and the image plane S.

(Embodiment 1)
Hereinafter, the zoom lens system according to the first embodiment will be described with reference to FIG.

FIG. 1 shows a lens arrangement diagram of the zoom lens system according to the first embodiment and its operation.

As shown in FIG. 1, in the zoom lens system of the present embodiment, the first lens group G1 having a positive power and the second lens group G2 having a negative power are sequentially arranged from the object side to the image side. The third lens group G3 having positive power, the fourth lens group G4 having positive power, the fifth lens group G5 having negative power, the sixth lens group G6 having positive power, and the negative It is composed of a seventh lens group G7 having power. The lens groups from the third lens group G3 to the seventh lens group G7 are examples of subsequent lens groups.

The first lens group G1 includes a first lens element L1 having a negative power, a second lens element L2 having a positive power, and a third lens element L3 having a positive power in order from the object side to the image side. And consists of.

The second lens group G2 includes a fourth lens element L4 having a positive power, a fifth lens element L5 having a negative power, and a sixth lens element L6 having a negative power in this order from the object side to the image side. , A seventh lens element L7 having a positive power, and an eighth lens element L8 having a negative power. The sixth lens element L6 and the seventh lens element L7 form a bonded lens that is bonded with an adhesive such as an ultraviolet curable resin.

The third lens group G3 is composed of a ninth lens element L9 having a positive power.

The fourth lens group G4 includes a tenth lens element L10 having a positive power, an aperture aperture A, an eleventh lens element L11 having a positive power, a twelfth lens element L12 having a negative power, and a negative lens element L12. The 13th lens element L13 having power, the 14th lens element L14 having positive power, the 15th lens element L15 having positive power, the 16th lens element L16 having negative power, and the positive power. It is composed of a 17th lens element L17 having the lens element L17. The 11th lens element L11 and the 12th lens element L12, the 13th lens element L13 and the 14th lens element L14, and the 16th lens element L16 and the 17th lens element L17 are adhesives such as an ultraviolet curable resin or the like. Consists of a bonded lens that is bonded with.

The fifth lens group G5 is composed of an 18th lens element L18 having a positive power and a 19th lens element L19 having a negative power. The 18th lens element L18 and the 19th lens element L19 form a bonded lens that is bonded with an adhesive such as an ultraviolet curable resin. The fifth lens group G5 is an example of the first focus lens group.

The sixth lens group G6 is composed of a twentieth lens element L20 having a positive power. The sixth lens group G6 is an example of the second focus lens group.

The seventh lens group G7 is composed of a 21st lens element L21 having a negative power and a 22nd lens element L22 having a positive power.

The aperture diaphragm A is arranged between the tenth lens element L10 of the fourth lens group G4 and the eleventh lens element L11.

Hereinafter, the lens elements constituting each lens group of the zoom lens system of the present embodiment will be described.

First, each lens element in the first lens group G1 will be described.

The first lens element L1 is a meniscus lens having a convex surface on the object side. The second lens element L2 is a biconvex lens. The third lens element L3 is a meniscus lens having a convex surface on the object side.

Next, each lens element in the second lens group G2 will be described.

The fourth lens element L4 is a biconvex lens. The fifth lens element L5 is a meniscus lens having a convex surface on the object side. The sixth lens element L6 is a biconcave lens. The seventh lens element L7 is a biconvex lens. The eighth lens element L8 is a biconcave lens.

Next, each lens element in the third lens group G3 will be described.

The ninth lens element L9 is a biconvex lens.

Next, the lens element in the fourth lens group G4 will be described.

The tenth lens element L10 is a meniscus lens having a convex surface on the object side. The eleventh lens element L11 is a meniscus lens having a convex surface on the image side. The twelfth lens element L12 is a biconcave lens. The thirteenth lens element L13 is a meniscus lens having a convex surface on the object side. The 14th lens element L14 is a meniscus lens having a convex surface on the object side. The fifteenth lens element L15 is a biconvex lens. The 16th lens element L16 is a meniscus lens having a convex surface on the image side. The 17th lens element L17 is a meniscus lens having a convex surface on the image side.

Further, the lens element in the fifth lens group G5 will be described.

The 18th lens element L18 is a meniscus lens having a convex surface on the image side. The 19th lens element L19 is a biconcave lens.

Further, the lens element in the sixth lens group G6 will be described.

The 20th lens element L20 is a biconvex lens.

Further, the lens element in the 7th lens group G7 will be described.

The 21st lens element L21 is a biconcave lens. The 22nd lens element L22 is a meniscus lens having a convex surface on the object side.

As described above, the zoom lens system of the present embodiment is composed of seven lens groups.

Then, each lens group of the zoom lens system of the present embodiment moves as shown by the arrow in FIG. 1 (c) when zooming from the wide-angle end (Wide) to the telephoto end (Tele) at the time of imaging. To do.

Specifically, the first lens group G1 is fixed, and the second lens group G2 moves from the object side to the image plane S side. The third lens group G3 moves to the object side. The aperture diaphragm A and the fourth lens group G4 are integrally fixed. Then, the fifth lens group G5 moves so as to draw a convex locus toward the image plane S side. The sixth lens group G6 moves to the image plane S side. The seventh lens group is fixed. Due to this movement, the distance between the first lens group G1 and the second lens group G2 increases and the distance between the second lens group G2 and the third lens group G3 decreases during zooming. The distance between the third lens group G3 and the fourth lens group G4 increases. The distance between the telephoto end of the fourth lens group G4 and the fifth lens group G5 is larger than that of the wide-angle end. The distance between the telephoto end of the fifth lens group G5 and the sixth lens group G6 is larger than that of the wide-angle end. The distance between the 6th lens group G6 and the 7th lens group G7 is reduced. The distance between the seventh lens group G7 and the image plane S is fixed.

As described above, each lens group moves along the optical axis L as shown by the arrow in FIG. 1 (c). Then, as shown in FIGS. 1 (a), (d), and (e), each lens group is arranged at the wide-angle end, the intermediate position, and the telephoto end.

That is, the zoom lens system of the present embodiment moves relatively. In other words, the spacing between each lens group changes. As a result, the zooming operation from the wide-angle end to the telephoto end is performed.

The fifth lens group G5 and the sixth lens group G6 constituting the focus lens group are shown by the arrows in FIG. 1 (b) when focusing from the infinity in-focus state to the near-junction in-focus state. , The fifth lens group G5 moves toward the image side along the optical axis L, and the sixth lens group G6 moves toward the object side.

(Embodiment 2)
Hereinafter, the zoom lens system according to the second embodiment will be described with reference to FIG.

FIG. 3 shows a lens arrangement diagram of the zoom lens system according to the second embodiment and its operation.

As shown in FIG. 3, in the zoom lens system of the present embodiment, the first lens group G1 having a positive power and the second lens group G2 having a negative power are sequentially arranged from the object side to the image side. The third lens group G3 having positive power, the fourth lens group G4 having positive power, the fifth lens group G5 having negative power, the sixth lens group G6 having positive power, and the negative It is composed of a seventh lens group G7 having power. The lens groups from the third lens group G3 to the seventh lens group G7 are examples of subsequent lens groups.

The first lens group G1 includes a first lens element L1 having a negative power, a second lens element L2 having a positive power, and a third lens element L3 having a positive power in order from the object side to the image side. And consists of.

The second lens group G2 includes a fourth lens element L4 having a positive power, a fifth lens element L5 having a negative power, and a sixth lens element L6 having a negative power in this order from the object side to the image side. , A seventh lens element L7 having a positive power, and an eighth lens element L8 having a negative power. The sixth lens element L6 and the seventh lens element L7 form a bonded lens that is bonded with an adhesive such as an ultraviolet curable resin.

The third lens group G3 is composed of a ninth lens element L9 having a positive power.

The fourth lens group G4 includes a tenth lens element L10 having a positive power, an aperture aperture A, an eleventh lens element L11 having a positive power, a twelfth lens element L12 having a negative power, and a negative lens element L12. The 13th lens element L13 having power, the 14th lens element L14 having positive power, the 15th lens element L15 having positive power, the 16th lens element L16 having negative power, and the positive power. It is composed of a 17th lens element L17 having the lens element L17. The 11th lens element L11 and the 12th lens element L12, the 13th lens element L13 and the 14th lens element L14, and the 16th lens element L16 and the 17th lens element L17 are adhesives such as an ultraviolet curable resin or the like. Consists of a bonded lens that is bonded with.

The fifth lens group G5 is composed of an 18th lens element L18 having a positive power and a 19th lens element L19 having a negative power. The 18th lens element L18 and the 19th lens element L19 form a bonded lens that is bonded with an adhesive such as an ultraviolet curable resin. The fifth lens group G5 is an example of the first focus lens group.

The sixth lens group G6 is composed of a twentieth lens element L20 having a positive power. The sixth lens group G6 is an example of the second focus lens group.

The seventh lens group G7 is composed of a 21st lens element L21 having a negative power and a 22nd lens element L22 having a positive power.

The aperture diaphragm A is arranged between the tenth lens element L10 of the fourth lens group G4 and the eleventh lens element L11.

Hereinafter, the lens elements constituting each lens group of the zoom lens system of the present embodiment will be described.

First, each lens element in the first lens group G1 will be described.

The first lens element L1 is a meniscus lens having a convex surface on the object side. The second lens element L2 is a biconvex lens. The third lens element L3 is a meniscus lens having a convex surface on the object side.

Next, each lens element in the second lens group G2 will be described.

The fourth lens element L4 is a biconvex lens. The fifth lens element L5 is a biconcave lens. The sixth lens element L6 is a biconcave lens. The seventh lens element L7 is a biconvex lens. The eighth lens element L8 is a biconcave lens.

Next, each lens element in the third lens group G3 will be described.

The ninth lens element L9 is a biconvex lens.

Next, the lens element in the fourth lens group G4 will be described.

The tenth lens element L10 is a meniscus lens having a convex surface on the object side. The eleventh lens element L11 is a meniscus lens having a convex surface on the image side. The twelfth lens element L12 is a biconcave lens. The thirteenth lens element L13 is a meniscus lens having a convex surface on the object side. The 14th lens element L14 is a meniscus lens having a convex surface on the object side. The fifteenth lens element L15 is a biconvex lens. The 16th lens element L16 is a meniscus lens having a convex surface on the image side. The 17th lens element L17 is a meniscus lens having a convex surface on the image side.

Further, the lens element in the fifth lens group G5 will be described.

The 18th lens element L18 is a biconvex lens. The 19th lens element L19 is a biconcave lens.

Further, the lens element in the sixth lens group G6 will be described.

The 20th lens element L20 is a biconvex lens.

Further, the lens element in the 7th lens group G7 will be described.

The 21st lens element L21 is a biconcave lens. The 22nd lens element L22 is a meniscus lens having a convex surface on the object side.

As described above, the zoom lens system of the present embodiment is composed of seven lens groups.

Then, each lens group of the zoom lens system of the present embodiment moves as shown by the arrow of FIG. 3C when zooming from the wide-angle end to the telephoto end at the time of imaging.

Specifically, the first lens group G1 is fixed, and the second lens group G2 moves from the object side to the image plane S side. The third lens group G3 moves to the object side. The aperture diaphragm A and the fourth lens group G4 are integrally fixed. Then, the fifth lens group G5 moves so as to draw a convex locus toward the image plane S side. The sixth lens group G6 moves to the image plane S side. The seventh lens group is fixed. Due to this movement, the distance between the first lens group G1 and the second lens group G2 increases and the distance between the second lens group G2 and the third lens group G3 decreases during zooming. The distance between the third lens group G3 and the fourth lens group G4 increases. The distance between the fourth lens group G4 and the fifth lens group G5 is the same at the wide-angle end and the telephoto end. The distance between the telephoto end of the fifth lens group G5 and the sixth lens group G6 is larger than that of the wide-angle end. The distance between the 6th lens group G6 and the 7th lens group G7 is reduced. The distance between the seventh lens group G7 and the image plane S is fixed.

As described above, each lens group moves along the optical axis as shown by the arrow in FIG. 3C. Then, as shown in FIGS. 3A, 3D, and 3E, each lens group is arranged at the wide-angle end, the intermediate position, and the telephoto end.

That is, the zoom lens system of the present embodiment moves relatively. In other words, the spacing between each lens group changes. As a result, the zooming operation from the wide-angle end to the telephoto end is performed.

The fifth lens group G5 and the sixth lens group G6 constituting the focus lens group are shown by the arrows in FIG. 3 (b) when focusing from the infinity in-focus state to the near-junction in-focus state. , The fifth lens group G5 moves toward the image side along the optical axis L, and the sixth lens group G6 moves toward the object side.

(Embodiment 3)
Hereinafter, the zoom lens system according to the third embodiment will be described with reference to FIG.

FIG. 5 shows a lens arrangement diagram of the zoom lens system according to the third embodiment and its operation.

As shown in FIG. 5, in the zoom lens system of the present embodiment, the first lens group G1 having a positive power and the second lens group G2 having a negative power are sequentially arranged from the object side to the image side. The third lens group G3 having positive power, the fourth lens group G4 having positive power, the fifth lens group G5 having negative power, the sixth lens group G6 having positive power, and the negative It is composed of a seventh lens group G7 having power. The lens groups from the third lens group G3 to the seventh lens group G7 are examples of subsequent lens groups.

The first lens group G1 includes a first lens element L1 having a negative power, a second lens element L2 having a positive power, and a third lens element L3 having a positive power in order from the object side to the image side. And consists of.

The second lens group G2 includes a fourth lens element L4 having a positive power, a fifth lens element L5 having a negative power, and a sixth lens element L6 having a negative power in this order from the object side to the image side. , A seventh lens element L7 having a positive power, and an eighth lens element L8 having a negative power. The sixth lens element L6 and the seventh lens element L7 form a bonded lens that is bonded with an adhesive such as an ultraviolet curable resin.

The third lens group G3 is composed of a ninth lens element L9 having a positive power.

The fourth lens group G4 includes a tenth lens element L10 having a positive power, an aperture aperture A, an eleventh lens element L11 having a positive power, a twelfth lens element L12 having a negative power, and a negative lens element L12. The 13th lens element L13 having power, the 14th lens element L14 having positive power, the 15th lens element L15 having positive power, the 16th lens element L16 having negative power, and the positive power. It is composed of a 17th lens element L17 having the lens element L17. The 11th lens element L11 and the 12th lens element L12, the 13th lens element L13 and the 14th lens element L14, and the 16th lens element L16 and the 17th lens element L17 are adhesives such as an ultraviolet curable resin or the like. Consists of a bonded lens that is bonded with.

The fifth lens group G5 is composed of an 18th lens element L18 having a positive power and a 19th lens element L19 having a negative power. The 18th lens element L18 and the 19th lens element L19 form a bonded lens that is bonded with an adhesive such as an ultraviolet curable resin. The fifth lens group G5 is an example of the first focus lens group.

The sixth lens group G6 is composed of a twentieth lens element L20 having a positive power. The sixth lens group G6 is an example of the second focus lens group.

The seventh lens group G7 is composed of a 21st lens element L21 having a negative power and a 22nd lens element L22 having a positive power.

The aperture diaphragm A is arranged between the tenth lens element L10 of the fourth lens group G4 and the eleventh lens element L11.

Hereinafter, the lens elements constituting each lens group of the zoom lens system of the present embodiment will be described.

First, each lens element in the first lens group G1 will be described.

The first lens element L1 is a meniscus lens having a convex surface on the object side. The second lens element L2 is a plano-convex lens having a convex surface on the object side. The third lens element L3 is a meniscus lens having a convex surface on the object side.

Next, each lens element in the second lens group G2 will be described.

The fourth lens element L4 is a biconvex lens. The fifth lens element L5 is a meniscus lens having a convex surface on the object side. The sixth lens element L6 is a biconcave lens. The seventh lens element L7 is a biconvex lens. The eighth lens element L8 is a biconcave lens.

Next, each lens element in the third lens group G3 will be described.

The ninth lens element L9 is a biconvex lens.

Next, the lens element in the fourth lens group G4 will be described.

The tenth lens element L10 is a meniscus lens having a convex surface on the object side. The eleventh lens element L11 is a meniscus lens having a convex surface on the image side. The twelfth lens element L12 is a biconcave lens. The thirteenth lens element L13 is a meniscus lens having a convex surface on the object side. The 14th lens element L14 is a meniscus lens having a convex surface on the object side. The fifteenth lens element L15 is a biconvex lens. The 16th lens element L16 is a meniscus lens having a convex surface on the image side. The 17th lens element L17 is a meniscus lens having a convex surface on the image side.

Further, the lens element in the fifth lens group G5 will be described.

The 18th lens element L18 is a plano-convex lens having a convex surface on the image plane S side. The 19th lens element L19 is a biconcave lens.

Further, the lens element in the sixth lens group G6 will be described.

The 20th lens element L20 is a biconvex lens.

Further, the lens element in the 7th lens group G7 will be described.

The 21st lens element L21 is a biconcave lens. The 22nd lens element L22 is a meniscus lens having a convex surface on the object side.

As described above, the zoom lens system of the present embodiment is composed of seven lens groups.

Then, each lens group of the zoom lens system of the present embodiment moves as shown by the arrow of FIG. 5C when zooming from the wide-angle end to the telephoto end at the time of imaging.

Specifically, the first lens group G1 is fixed, and the second lens group G2 moves from the object side to the image plane S side. The third lens group G3 moves to the object side. The aperture diaphragm A and the fourth lens group G4 are integrally fixed. Then, the fifth lens group G5 moves so as to draw a convex locus toward the image plane S side. The sixth lens group G6 moves to the image plane S side, and the seventh lens group is fixed. Due to this movement, the distance between the first lens group G1 and the second lens group G2 increases and the distance between the second lens group G2 and the third lens group G3 decreases during zooming. The distance between the third lens group G3 and the fourth lens group G4 increases. The distance between the telephoto end of the fourth lens group G4 and the fifth lens group G5 is larger than that of the wide-angle end. The distance between the telephoto end of the fifth lens group G5 and the sixth lens group G6 is larger than that of the wide-angle end. The distance between the 6th lens group G6 and the 7th lens group G7 is reduced. The distance between the seventh lens group G7 and the image plane S is fixed.

As described above, each lens group moves along the optical axis L as shown by the arrow in FIG. 5 (c). Then, as shown in FIGS. 5A, 5D, and 5E, each lens group is arranged at the wide-angle end, the intermediate position, and the telephoto end.

That is, the zoom lens system of the present embodiment moves relatively. In other words, the spacing between each lens group changes. As a result, the zooming operation from the wide-angle end to the telephoto end is performed.

The fifth lens group G5 and the sixth lens group G6 constituting the focus lens group are shown by the arrows in FIG. 5 (b) when focusing from the infinity in-focus state to the near-junction in-focus state. , The fifth lens group G5 moves toward the image side along the optical axis L, and the sixth lens group G6 moves toward the object side.

(Embodiment 4)
Hereinafter, the zoom lens system according to the fourth embodiment will be described with reference to FIG. 7.

FIG. 7 shows a lens arrangement diagram of the zoom lens system according to the fourth embodiment and its operation.

As shown in FIG. 7, in the zoom lens system of the present embodiment, the first lens group G1 having a positive power and the second lens group G2 having a negative power are sequentially arranged from the object side to the image side. It is composed of a third lens group G3 having a positive power, a fourth lens group G4 having a negative power, a fifth lens group G5 having a positive power, and a sixth lens group G6 having a negative power. Will be done. The lens groups from the third lens group G3 to the sixth lens group G6 are examples of subsequent lens groups.

The first lens group G1 includes a first lens element L1 having a negative power, a second lens element L2 having a positive power, and a third lens element L3 having a positive power in order from the object side to the image side. And consists of.

The second lens group G2 includes a fourth lens element L4 having a positive power, a fifth lens element L5 having a negative power, and a sixth lens element L6 having a negative power in this order from the object side to the image side. , A seventh lens element L7 having a positive power, and an eighth lens element L8 having a negative power. The sixth lens element L6 and the seventh lens element L7 form a bonded lens that is bonded with an adhesive such as an ultraviolet curable resin.

The third lens group G3 includes a ninth lens element L9 having a positive power, a tenth lens element L10 having a positive power, an aperture aperture A, and an eleventh lens element L11 having a positive power. The 12th lens element L12 having power, the 13th lens element L13 having negative power, the 14th lens element L14 having positive power, the 15th lens element L15 having positive power, and the negative power It is composed of a 16th lens element L16 having a positive power and a 17th lens element L17 having a positive power. The 11th lens element L11 and the 12th lens element L12, the 13th lens element L13 and the 14th lens element L14, and the 16th lens element L16 and the 17th lens element L17 are adhesives such as an ultraviolet curable resin or the like. Consists of a bonded lens that is bonded with.

The fourth lens group G4 is composed of an 18th lens element L18 having a positive power and a 19th lens element L19 having a negative power. The 18th lens element L18 and the 19th lens element L19 form a bonded lens that is bonded with an adhesive such as an ultraviolet curable resin. The fourth lens group G4 is an example of the first focus lens group.

The fifth lens group G5 is composed of a twentieth lens element L20 having a positive power. The fifth lens group G5 is an example of the second focus lens group.

The sixth lens group G6 is composed of a 21st lens element L21 having a negative power and a 22nd lens element L22 having a positive power.

The aperture diaphragm A is arranged between the tenth lens element L10 of the third lens group G3 and the eleventh lens element L11.

Hereinafter, the lens elements constituting each lens group of the zoom lens system of the present embodiment will be described.

First, each lens element in the first lens group G1 will be described.

The first lens element L1 is a meniscus lens having a convex surface on the object side. The second lens element L2 is a biconvex lens. The third lens element L3 is a meniscus lens having a convex surface on the object side.

Next, each lens element in the second lens group G2 will be described.

The fourth lens element L4 is a biconvex lens. The fifth lens element L5 is a biconcave lens. The sixth lens element L6 is a biconcave lens. The seventh lens element L7 is a meniscus lens having a convex surface on the object side. The eighth lens element L8 is a meniscus lens having a convex surface on the image side.

Next, each lens element in the third lens group G3 will be described.

The ninth lens element L9 is a biconvex lens. The tenth lens element L10 is a meniscus lens having a convex surface on the object side. The eleventh lens element L11 is a meniscus lens having a convex surface on the image side. The twelfth lens element L12 is a biconcave lens. The thirteenth lens element L13 is a meniscus lens having a convex surface on the object side. The 14th lens element L14 is a meniscus lens having a convex surface on the object side. The fifteenth lens element L15 is a biconvex lens. The 16th lens element L16 is a meniscus lens having a convex surface on the image side. The 17th lens element L17 is a meniscus lens having a convex surface on the image side.

Further, the lens element in the fourth lens group G4 will be described.

The 18th lens element L18 is a meniscus lens having a convex surface on the image side. The 19th lens element L19 is a biconcave lens.

Further, the lens element in the fifth lens group G5 will be described.

The 20th lens element L20 is a biconvex lens.

Further, the lens element in the sixth lens group G6 will be described.

The 21st lens element L21 is a biconcave lens. The 22nd lens element L22 is a meniscus lens having a convex surface on the object side.

As described above, the zoom lens system of the present embodiment is composed of six lens groups.

Then, each lens group of the zoom lens system of the present embodiment moves as shown by the arrow of FIG. 7C when zooming from the wide-angle end to the telephoto end at the time of imaging.

Specifically, the first lens group G1 is fixed, and the second lens group G2 moves from the object side to the image plane S side. The aperture diaphragm A and the third lens group G3 are integrally fixed. Then, the fourth lens group G4 moves so as to draw a convex locus toward the image plane S side. The fifth lens group G5 moves so as to draw a convex locus toward the object side. The sixth lens group is fixed. Due to this movement, the distance between the first lens group G1 and the second lens group G2 increases and the distance between the second lens group G2 and the third lens group G3 decreases during zooming. The distance between the telephoto end of the third lens group G3 and the fourth lens group G4 is larger than that of the wide-angle end. The distance between the telephoto end of the fourth lens group G4 and the fifth lens group G5 is larger than that of the wide-angle end. The distance between the telephoto end of the fifth lens group G5 and the sixth lens group G6 is smaller than that of the wide-angle end. The distance between the sixth lens group G6 and the image plane S is fixed.

As described above, each lens group moves along the optical axis L as shown by the arrow in FIG. 7 (c). Then, as shown in FIGS. 7A, 7D, and 7E, each lens group is arranged at the wide-angle end, the intermediate position, and the telephoto end.

That is, the zoom lens system of the present embodiment moves relatively. In other words, the spacing between each lens group changes. As a result, the zooming operation from the wide-angle end to the telephoto end is performed.

The fourth lens group G4 and the fifth lens group G5 constituting the focus lens group are shown by the arrows in FIG. 7 (b) when focusing from the infinity in-focus state to the near-junction in-focus state. , The fourth lens group G4 moves toward the image side along the optical axis L, and the fifth lens group G5 moves toward the object side.

(Conditions and effects, etc.)
Hereinafter, the conditions under which the configuration of the zoom lens system according to the first to fourth embodiments can be satisfied will be described.

That is, a plurality of possible conditions are defined for the zoom lens system according to each embodiment. In this case, a configuration of a zoom lens system that satisfies all of a plurality of conditions is most effective.

However, by satisfying the individual conditions described below, it is possible to obtain a zoom lens system that exhibits the corresponding effects.

For example, in the zoom lens system according to the first to fourth embodiments, the first lens group having a positive power, the second lens group having a negative power, and the subsequent lens group have a positive power in this order from the object side to the image side. It is equipped with a lens group. The succeeding lens group is a first focus lens group having a negative power that moves along the optical axis when focusing from an infinity in-focus state to a close object in-focus state, and an image side of the first focus lens group. A second focus lens group, which is adjacent to the lens and has a positive power, is provided. During zooming from the wide-angle end to the telephoto end, the distance between each lens group changes, and the first lens group is fixed to the image plane.

And, for example, it is desirable to satisfy the following condition (1).

−0.23 <f2 / TTL <−0.15 ・ ・ ・ (1)
here,
TTL: Overall optical length at the telephoto end,
f2: Focal length of the second lens group,
Is.

That is, the condition (1) is a condition that defines the focal length of the second lens group with respect to the total optical length.

When the ratio of f2 / TTL satisfies the condition (1), the total length can be shortened and the amount of aberration generated can be suppressed. If the ratio of f2 / TTL is less than the lower limit of the condition (1) (−0.23), the amount of movement of the second lens group becomes large and the lens system becomes large, which is not preferable. On the contrary, if the ratio of f2 / TTL exceeds the upper limit value (-0.15) of the condition (1), it becomes difficult to correct various aberrations, which is not preferable.

At this time, it is more preferable if either of the following conditions (1a) and (1b) is satisfied.

-0.22 <f2 / TTL ... (1a)
f2 / TTL <-0.17 ... (1b)
As a result, the above-mentioned effect is further improved.

Further, it is more preferable if the following condition (1c) is satisfied.

f2 / TTL <-0.18 ... (1c)
As a result, the above-mentioned effect is further improved.

Further, for example, it is desirable to satisfy the following condition (2).

-3.2 <(1-β1 x β1) x (β2 x β2) <-2.4 ... (2)
here,
β1: Horizontal magnification at the telephoto end of the first focus lens group,
β2: Horizontal magnification at the telephoto end of the image-side optical system from the first focus lens group,
Is.

That is, the condition (2) is a condition that defines the focus position sensitivity of the first focus lens group.

When (1-β1 × β1) × (β2 × β2) is less than the lower limit value (-3.2) of the condition (2), the position sensitivity of the focus lens group becomes high and the control of the focus lens group is controlled. It becomes difficult and is not preferable.

On the contrary, when (1-β1 × β1) × (β2 × β2) exceeds the upper limit value (-2.4) of the condition (2), the amount of movement of the focus lens group becomes large and the lens system becomes large. It is not preferable because it becomes

At this time, it is more preferable if either of the following conditions (2a) and (2b) is satisfied.

-3.10 <(1-β1 x β1) x (β2 x β2) ... (2a)
(1-β1 × β1) × (β2 × β2) <-2.45 ... (2b)
As a result, the above-mentioned effect is further improved.

Further, it is more preferable if either of the following conditions (2c) or (2d) is satisfied.

-3.0 <(1-β1 x β1) x (β2 x β2) ... (2c)
(1-β1 × β1) × (β2 × β2) <-2.50 ... (2d)
As a result, the above-mentioned effect is further improved.

Further, for example, the first focus lens group includes a lens element having a positive power and a lens element having a negative power, and the second focus lens group includes one lens element having a positive power. desirable.

By having a lens element having a positive power and a lens element having a negative power, the first focus lens group can suppress the occurrence of axial chromatic aberration due to focus fluctuation. By forming the second focus lens group from one lens, the weight of the focus lens group can be reduced.

Further, for example, the subsequent lens group includes an aperture diaphragm, and the lens element adjacent to the object side of the aperture diaphragm and the lens element adjacent to the image side of the aperture diaphragm have positive power, and the following condition (3) , (4) is satisfied.

vd1> 65 ... (3)
vd2> 65 ... (4)
here,
vd1: Abbe number of lens elements adjacent to the object side of the aperture diaphragm, vd2: Abbe number of lens elements adjacent to the image side of the aperture diaphragm,
Is.

The Abbe number of the lens element adjacent to the object side of the aperture diaphragm is 65 or less, which is the lower limit of the condition (3), and the Abbe number of the lens element adjacent to the image side of the aperture diaphragm is the lower limit of the condition (4). When the value is 65 or less, the chromatic aberration of magnification becomes large in the entire zoom range, and the performance cannot be ensured.

At this time, it is more preferable if either of the following conditions (3a) or (4a) is satisfied.

vd1> 75 ... (3a)
vd2> 75 ... (4a)
As a result, the above-mentioned effect is further improved.

Further, it is more preferable if either of the following conditions (3b) or (4b) is satisfied.

vd1> 80 ... (3b)
vd2> 80 ... (4b)
As a result, the above-mentioned effect is further improved.

(Rough configuration of an imaging device to which the first embodiment is applied)
Hereinafter, a schematic configuration of an image pickup apparatus to which the room lens system according to the first embodiment is applied will be described with reference to FIG.

FIG. 9 is a schematic configuration diagram of an image pickup apparatus including the zoom lens system according to the first embodiment. In FIG. 9, an example in which the zoom lens system of the first embodiment is applied to the image pickup apparatus will be described, but the zoom lens system of the second to fourth embodiments may be applied to the image pickup apparatus, and the same effect may be obtained. Is obtained.

As shown in FIG. 9, the image pickup apparatus 100 includes a housing 104, a lens barrel 302 connected to the housing 104, and the like. The housing 104 has an image sensor 102 inside. The lens barrel 302 includes a zoom lens system 101 inside. The image pickup device 100 is exemplified by, for example, a digital camera.

The zoom lens system 101 includes a first lens group G1, a second lens group G2, a third lens group G3, an aperture diaphragm A, a fourth lens group G4, a fifth lens group G5, and a sixth lens group G6. , 7th lens group G7, etc., and is housed in the lens barrel 302.

The lens barrel 302 holds each lens group constituting the zoom lens system 101 and the aperture diaphragm A.

The image sensor 102 is arranged at the position of the image plane S in the zoom lens system of the present embodiment.

Further, the housing 104 includes an actuator, a lens frame, and the like inside. Each lens group constituting the zoom lens system 101 and an aperture diaphragm A or the like are movably attached to or coupled to the actuator or the lens frame during zooming.

As described above, the image pickup apparatus 100 is configured. As a result, it is possible to realize an image pickup apparatus 100 in which various aberrations are satisfactorily corrected.

In the above description, an example in which the zoom lens system is applied to a digital camera has been described, but the present invention is not limited to this. For example, it may be applied to an imaging device such as a surveillance camera or a smartphone.

(Rough configuration of camera system to which Embodiment 1 is applied)
Hereinafter, a schematic configuration of a camera system to which the room lens system according to the first embodiment is applied will be described with reference to FIG.

FIG. 10 is a schematic configuration diagram of a camera system including the zoom lens system according to the first embodiment. In FIG. 10, an example in which the zoom lens system of the first embodiment is applied to the camera system will be described, but the zoom lens system of the second to fourth embodiments may be applied to the camera system, and the same effect may be obtained. Is obtained. Further, the camera system 200 is exemplified by, for example, an interchangeable lens type digital camera system.

As shown in FIG. 10, the camera system 200 includes a camera body 201, an interchangeable lens device 300 that is detachably connected to the camera body 201, and the like.

The camera body 201 includes an image sensor 202, a monitor 203, a memory (not shown) for storing an image signal, a camera mount portion 204, a finder 205, and the like. The image sensor 202 is composed of, for example, a CMOS image sensor, receives an optical image formed by the zoom lens system of the interchangeable lens device 300, and converts it into an electrical image signal. The monitor 203 is composed of, for example, an LCD, and displays an image signal converted by the image sensor 202.

The interchangeable lens device 300 includes a first lens group G1, a second lens group G2, a third lens group G3, a fourth lens group G4, an aperture aperture A, a fifth lens group G5, and a sixth lens group G6. , A zoom lens system 301 composed of a seventh lens group G7 and the like.

The lens barrel 302 holds each lens group of the zoom lens system 301 and the aperture diaphragm A. Further, the lens barrel 302 includes a lens mount portion 304 connected to the camera mount portion 204 of the camera body 201.

The camera mount portion 204 of the camera body 201 and the lens mount portion 304 of the lens barrel 302 are physically connected by, for example, a bayonet mechanism. Then, the controller (not shown) in the camera body 201 and the controller (not shown) in the interchangeable lens device 300 are electrically connected. That is, the camera mount unit 204 and the lens mount unit 304 function as an interface that enables mutual signal exchange.

The zoom lens system 301 is composed of each lens group held in the lens barrel 302 of the interchangeable lens device 300, a parallel flat plate P in the camera body 201, and the like.

The zoom lens system 301 includes an actuator and a lens frame controlled by a controller inside. Each lens group constituting the zoom lens system 301 and an aperture diaphragm A or the like are movably attached to or coupled to the actuator or the lens frame during zooming.

As described above, the camera system 200 is configured. As a result, it is possible to realize a camera system 200 in which various aberrations are satisfactorily corrected.

(Other embodiments)
The techniques disclosed in the present application have been described above by taking the first to fourth embodiments as examples.

However, the technique in the present disclosure is not limited to this, and can be applied to embodiments in which changes, replacements, additions, omissions, etc. are made.

In the zoom lens system according to the first to fourth embodiments, the example of using the entire zooming range from the wide-angle end to the telephoto end has been described, but it is not always necessary to use the entire zooming range. For example, a range in which optical performance is ensured may be cut out according to a desired zooming range and used as a zoom lens system. That is, in the following, it may be used as a zoom lens system having a lower magnification than the zoom lens system described in the numerical examples 1 to 4 corresponding to the first to fourth embodiments. Further, a focal length in which optical performance is ensured may be cut out according to a desired zooming position and used as a single focus lens system.

Further, in the first to fourth embodiments, each lens group constituting the zoom lens system is deflected at the interface between refracting lens elements (that is, media having different refractive indexes) that deflect the incident light rays by refraction. Although the explanation has been given with an example in which only the lens element of the type to be performed) is used, the present invention is not limited to this. For example, it may be composed of a diffraction type lens element that deflects an incident light ray by diffraction, or a refraction / diffraction hybrid type lens element that deflects an incident light ray by a combination of a diffraction action and a refractive action. Further, each lens group may be composed of a refractive index distribution type lens element or the like that deflects the incident light ray by the refractive index distribution in the medium. In particular, in a refraction / diffraction hybrid type lens element, it is more preferable to form a diffraction structure at the interface between media having different refractive indexes because the wavelength dependence of diffraction efficiency is improved. Optical aberrations such as chromatic aberration of magnification may be corrected on the camera body side. As a result, it is possible to realize a camera system or the like in which various aberrations in the entire zoom range are satisfactorily corrected and a high close-up shooting capability is provided.

(Numerical example)
Hereinafter, numerical examples specifically implemented in the configuration of the zoom lens system according to the first to fourth embodiments will be described with reference to FIGS. 2, 4, 6, and 8.

In each numerical example, the unit of length in the table is "mm", and the unit of angle of view is "°". Further, in each numerical example, r is the radius of curvature, d is the surface spacing, nd is the refractive index for the d line, and νd (also referred to as vd) is the Abbe number for the d line. Further, in each numerical example, the surface marked with * is an aspherical surface. The aspherical shape is defined by the following equation.

Here, Z is the distance from a point on the aspherical surface at the height h from the optical axis to the tangent plane of the aspherical vertex, h is the height from the optical axis, r is the radius of curvature of the apex, and κ is the conical constant. An is an nth-order aspherical coefficient.

2, FIG. 4, FIG. 6, and FIG. 8 are longitudinal aberration diagrams of the zoom lens system according to the numerical examples 1 to 4 corresponding to the first to fourth embodiments in the infinity in-focus state.

Here, in each longitudinal aberration diagram, (a) represents each longitudinal aberration at the wide-angle end, (b) represents an intermediate position, and (c) represents each longitudinal aberration at the telephoto end. (A) to (c) of each longitudinal aberration diagram are spherical aberration (SA: Physical Aberration (mm)), astigmatism (AST: Astigmatism (mm)), and distortion (DIS: Distortion (%)) in this order from the left side. ) Is shown.

In the spherical aberration diagram, the vertical axis represents the F number (indicated by "F" in the figure), the solid line is the d-line, the short dashed line is the F-line, and the long dashed line is the C-line (indicated by "F"). It shows the characteristics for C-line). In the astigmatism diagram, the vertical axis represents the image height (indicated by "H" in the figure), the solid line represents the sagittal plane (indicated by "s" in the figure), and the broken line represents the meridional plane (indicated by "m" in the figure). The characteristics for (shown by) are shown. Further, in the distortion diagram, the vertical axis represents the image height (indicated by "H" in the figure).

(Numerical Example 1)
The numerical embodiment 1 of the zoom lens system corresponding to the first embodiment shown in FIG. 1 is shown below. Specifically, as Numerical Example 1, surface data (Table 1), aspherical data (Table 2), and various data in the infinity in-focus state are shown in (Table 3A) to (Table 3D).

(Table 1: Surface data)
Face number rd nd vd
Paraboloid ∞
1 113.88640 2.40000 1.90366 31.3
2 73.34300 1.40000
3 73.26970 10.93870 1.43700 95.1
4-1099.60980 0.20000
5 73.01210 9.06240 1.43700 95.1
6 1427.78470 Variable
7 325.23860 3.81730 1.75520 27.5
8-237.64580 0.20000
9 1883.85250 1.50000 1.70154 41.1
10 36.62590 9.35040
11 -106.80870 1.50000 1.49700 81.6
12 41.55010 0.01000 1.56732 42.8
13 41.55010 6.19030 1.90366 31.3
14 -2919.09450 4.34720
15 -47.29410 1.50000 1.62299 58.1
16 1090.46650 Variable
17 72.89840 6.20430 1.83400 37.3
18 -125.91930 Variable
19 54.15970 3.50000 1.49700 81.6
20 129.18630 2.70000
21 (Aperture) ∞ 3.00000
22 -306.68430 4.46560 1.43700 95.1
23 -41.65960 0.01000 1.56732 42.8
24-41.65960 1.20000 1.84666 23.8
25 50.74240 2.40000
26 38.51610 1.50000 1.84666 23.8
27 29.55610 0.01000 1.56732 42.8
28 29.55610 6.00000 1.49700 81.6
29 446.83420 0.30000
30 * 85.84360 5.40000 1.58699 59.5
31 * -66.56740 3.00000
32 -55.00390 1.40000 1.58144 40.9
33 -317.62630 0.01000 1.56732 42.8
34 -317.62630 3.70000 1.84666 23.8
35 -47.99260 Variable
36 -3242.45700 3.30340 1.86966 20.0
37 -45.68510 0.01000 1.56732 42.8
38 -45.68510 0.70000 1.70154 41.1
39 37.66840 Variable
40 328.89510 4.21710 1.72825 28.3
41 -62.10320 Variable
42 -44.10590 1.40000 1.84666 23.8
43 238.35540 0.20000
44 47.99790 4.81740 1.65844 50.9
45 198.71610 31.00000
46 ∞ 2.10000 1.51680 64.2
47 ∞ BF
Image plane ∞
(Table 2: Aspherical data)
30th page
K = 1.00141E + 01, A4 = -3.83964E-06, A6 = -9.27978E-09, A8 = 9.80778E-11
A10 = -3.01332E-13, A12 = 3.69143E-16, A14 = 8.53756E-19
31st page
K = -1.56601E + 00, A4 = 2.33763E-06, A6 = -4.63015E-09, A8 = 5.44291E-11
A10 = 9.02742E-15, A12 = -6.65900E-16, A14 = 2.27920E-18
(Various data in infinity in focus)
(Table 3A: Various data)
Zoom ratio 2.66791
Wide-angle medium telephoto focal length 72.4503 120.0005 193.2912
F number 2.85653 2.91267 2.92713
Angle of view 16.8530 10.1321 6.2907
Image height 21.6300 21.6300 21.6300
Lens overall length 225.0000 224.9999 224.9998
BF 1.0900 1.0900 1.0900
d6 1.0000 21.9842 40.3077
d16 44.0729 20.6237 1.0000
d18 1.0000 3.4650 4.7651
d35 2.4000 5.5734 3.4440
d39 22.5695 21.2927 26.0456
d41 7.9035 6.0068 3.3833
Entrance pupil position 82.1783 134.7646 197.2441
Exit pupil position -92.4390 -92.1079 -96.4288
Front principal point position 97.8562 98.4306 2.9755
Rear principal point position 152.5684 105.0025 31.6817
(Table 3B: Single lens data)
Lens start surface focal length
1 1 -234.5765
2 3 157.6379
3 5 175.7220
4 7 182.3560
5 9 -53.2606
6 11 -59.9868
7 13 45.3796
8 15 -72.7218
9 17 56.1560
10 19 184.7774
11 22 109.7534
12 24 -26.8606
13 26 -162.5374
14 28 63.3790
15 30 64.7224
16 32 -114.6371
17 34 66.3563
18 36 53.2571
19 38 -29.3273
20 40 72.0600
21 42 -43.8597
22 44 94.9073
(Table 3C: Zoom lens group data)
Focal length of the group Lens configuration length Front principal point position Posterior principal point position
1 1 130.46702 24.00110 8.13223 15.21362
2 7 -43.27443 28.41520 11.62516 19.61717
3 17 56.15597 6.20430 1.25824 4.03091
4 19 88.74426 38.59560 33.82281 43.74123
5 36 -65.82216 4.01340 2.24797 4.07731
6 40 72.06001 4.21710 2.06190 3.82776
7 42 -81.42384 39.51740 0.18261 3.49061
(Table 3D: Zoom lens group magnification)
Group starting surface wide-angle intermediate telephoto
1 1 0.00000 0.00000 0.00000
2 7 -0.65787 -0.96604 -1.63471
3 17 -0.80549 -0.94216 -0.81485
4 19 0.57951 0.56044 0.59203
5 36 2.35010 2.23205 2.18216
6 40 0.52846 0.55488 0.59149
7 42 1.45608 1.45588 1.45552
(Numerical Example 2)
The numerical example 2 of the zoom lens system corresponding to the second embodiment shown in FIG. 3 is shown below. Specifically, as Numerical Example 2, surface data (Table 4), aspherical data (Table 5), and various data in the infinity in-focus state are shown in (Table 6A) to (Table 6D).

(Table 4: Surface data)
Face number rd nd vd
Paraboloid ∞
1 115.01390 2.40000 1.90366 31.3
2 74.87220 1.40000
3 74.63720 10.95010 1.43700 95.1
4 -823.61540 0.19990
5 74.02740 8.89300 1.43700 95.1
6 1409.09570 Variable
7 365.06730 3.82440 1.75520 27.5
8-208.54950 0.20000
9 -1032.78640 1.50000 1.70154 41.1
10 38.85370 8.98180
11 -106.88720 1.50000 1.49700 81.6
12 43.12630 0.01000 1.56732 42.8
13 43.12630 5.96460 1.90366 31.3
14 -954.05210 3.81390
15 -50.87530 1.50000 1.62299 58.1
16 337.11630 Variable
17 69.94050 6.00630 1.83400 37.3
18 -130.24940 Variable
19 54.68330 3.50000 1.49700 81.6
20 158.96810 2.70000
21 (Aperture) ∞ 3.00000
22 -180.40520 4.02720 1.43700 95.1
23 -41.07040 0.01000 1.56732 42.8
24-41.07040 1.20000 1.84666 23.8
25 49.55530 2.40000
26 36.99620 1.50000 1.84666 23.8
27 28.45760 0.01000 1.56732 42.8
28 28.45760 6.00000 1.49700 81.6
29 453.26390 0.30000
30 * 85.01880 5.40000 1.58699 59.5
31 * -61.96600 3.00000
32 -49.36100 1.40000 1.58144 40.9
33 -241.88390 0.01000 1.56732 42.8
34 -241.88390 3.70000 1.84666 23.8
35 -44.20610 Variable
36 2185.63770 3.30000 1.86966 20.0
37 -47.71770 0.01000 1.56732 42.8
38 -47.71770 0.70000 1.70154 41.1
39 34.86430 Variable
40 1195.45410 3.61240 1.72825 28.3
41 -63.58010 Variable
42 -44.56940 1.40000 1.84666 23.8
43 816.00560 0.20000
44 47.24300 4.39000 1.65844 50.9
45 161.73960 31.00000
46 ∞ 2.10000 1.51680 64.2
47 ∞ BF
Image plane ∞
(Table 5: Aspherical data)
30th page
K = 9.70174E + 00, A4 = -4.09298E-06, A6 = -7.92148E-09, A8 = 9.96901E-11
A10 = -3.04923E-13, A12 = 3.79913E-16, A14 = 1.15209E-18
31st page
K = -1.83440E + 00, A4 = 2.46038E-06, A6 = -3.85122E-09, A8 = 6.35691E-11
A10 = -2.67590E-14, A12 = -6.15399E-16, A14 = 2.63822E-18
(Various data in infinity in focus)
(Table 6A: Various data)
Zoom ratio 2.66390
Wide-angle medium telephoto focal length 72.4500 120.0900 192.9994
F number 2.87323 2.92041 2.92669
Angle of view 16.9028 10.1283 6.3000
Image height 21.6300 21.6300 21.6300
Lens overall length 219.9998 219.9997 219.9996
BF 1.0900 1.0900 1.0900
d6 1.0000 22.1603 40.7544
d16 43.6861 20.3406 0.9998
d18 1.0000 3.1851 3.9316
d35 2.4000 5.2067 2.4000
d39 19.5014 19.6036 25.9734
d41 9.3087 6.3998 2.8368
Entrance pupil position 81.6010 134.5298 196.7852
Exit pupil position -90.1095 -90.6963 -96.4174
Front principal point position 95.8066 95.5910 3.3483
Rear principal point position 147.5606 99.8989 26.9732
(Table 6B: Single lens data)
Lens start surface focal length
1 1 -244.3290
2 3 157.1853
3 5 178.4301
4 7 176.2568
5 9 -53.3445
6 11 -61.6232
7 13 45.7902
8 15 -70.8494
9 17 55.3174
10 19 165.8736
11 22 120.6245
12 24 -26.3650
13 26 -158.3894
14 28 60.8097
15 30 61.9028
16 32 -106.9464
17 34 63.3446
18 36 53.7338
19 38 -28.6158
20 40 82.9968
21 42 -49.8777
22 44 99.8359
(Table 6C: Zoom lens group data)
Focal length of the group Lens configuration length Front principal point position Posterior principal point position
1 1 128.73845 23.84300 8.09431 15.12369
2 7 -43.71450 27.29470 11.24886 18.97663
3 17 55.31743 6.00630 1.16001 3.84603
4 19 84.18946 38.15720 33.55825 43.43835
5 36 -61.89696 4.01000 2.33158 4.15592
6 40 82.99682 3.61240 1.98706 3.50672
7 42 -99.36182 39.09000 0.19601 3.33607
(Table 6D: Zoom lens group magnification)
Group starting surface wide-angle intermediate telephoto
1 1 0.00000 0.00000 0.00000
2 7 -0.68244 -1.01909 -1.79885
3 17 -0.77482 -0.88134 -0.71367
4 19 0.57803 0.56368 0.60422
5 36 2.39708 2.25732 2.20847
6 40 0.56030 0.59549 0.63852
7 42 1.37091 1.37070 1.37053
(Numerical Example 3)
The numerical embodiment 3 of the zoom lens system corresponding to the third embodiment shown in FIG. 5 is shown below. Specifically, as Numerical Example 3, surface data (Table 7), aspherical data (Table 8), and various data in the infinity in-focus state are shown in (Table 9A) to (Table 9D).

(Table 7: Surface data)
Face number rd nd vd
Paraboloid ∞
1 131.22820 2.40000 1.90366 31.3
2 79.03970 1.40000
3 80.37000 9.50000 1.49700 81.6
4 ∞ 0.20000
5 76.83580 8.90000 1.43700 95.1
6 1898.65470 Variable
7 487.43250 3.80000 1.60562 43.7
8-192.02740 0.20000
9 856.43360 1.50000 1.69680 55.5
10 40.43500 9.62500
11 -84.65890 1.50000 1.48749 70.4
12 47.18280 0.01000 1.56732 42.8
13 47.18280 6.20000 1.90366 31.3
14 -305.28090 3.41310
15 -53.25870 1.50000 1.60311 60.7
16 319.52970 Variable
17 64.04950 6.40000 1.80450 39.6
18 -141.71410 Variable
19 60.12400 3.50000 1.49700 81.6
20 171.57080 2.70000
21 (Aperture) ∞ 3.00000
22 -173.76030 3.79000 1.43700 95.1
23 -44.77020 0.01000 1.56732 42.8
24-44.77020 1.20000 1.84666 23.8
25 50.14780 2.40000
26 35.43740 1.50000 1.84666 23.8
27 27.25420 0.01000 1.56732 42.8
28 27.25420 6.00000 1.49700 81.6
29 342.12900 0.30000
30 * 82.95250 5.40000 1.58578 59.5
31 * -60.73600 3.00000
32 -43.73030 1.40000 1.69350 53.2
33 -320.32490 0.01000 1.56732 42.8
34 -320.32490 3.70000 1.85883 30.0
35 -43.18870 Variable
36 ∞ 3.30000 1.86966 20.0
37 -46.45840 0.01000 1.56732 42.8
38 -46.45840 0.70000 1.70154 41.1
39 35.13270 Variable
40 491.75140 4.20000 1.84666 23.8
41 -61.65070 Variable
42 -46.98310 1.40000 1.84666 23.8
43 117.64710 0.20000
44 49.62630 5.00000 1.71700 47.9
45 464.32830 31.00000
46 ∞ 2.10000 1.51680 64.2
47 ∞ BF
Image plane ∞
(Table 8: Aspherical data)
30th page
K = 9.97221E + 00, A4 = -3.94139E-06, A6 = -6.42008E-09, A8 = 9.84655E-11
A10 = -2.27304E-13, A12 = -2.10054E-17, A14 = 2.31090E-18
31st page
K = -5.11777E + 00, A4 = 9.64000E-07, A6 = -3.12961E-09, A8 = 9.40918E-11
A10 = -1.49427E-13, A12 = -4.27405E-16, A14 = 3.25178E-18
(Various data in infinity in focus)
(Table 9A: Various data)
Zoom ratio 2.66392
Wide-angle medium telephoto focal length 72.4497 120.0003 193.0002
F number 2.83239 2.89398 2.92822
Angle of view 16.8306 10.1115 6.2985
Image height 21.6300 21.6300 21.6300
Lens overall length 224.9999 224.9998 224.9998
BF 1.0900 1.0900 1.0900
d6 1.0000 24.4387 44.9034
d16 47.7393 22.3112 1.0000
d18 1.0000 2.9893 3.8358
d35 2.4000 5.2518 3.0651
d39 20.1578 20.0419 26.0482
d41 9.2347 6.4988 2.6792
Entrance pupil position 82.3122 137.1747 199.6044
Exit pupil position -92.4947 -93.3909 -100.2250
Front principal point position 98.0167 102.9370 20.8829
Rear principal point position 152.5560 104.9713 31.9815
(Table 9B: Single lens data)
Lens start surface focal length
1 1 -224.8428
2 3 161.7111
3 5 182.9689
4 7 227.9454
5 9 -60.9509
6 11 -61.9187
7 13 45.6044
8 15 -75.5762
9 17 55.6028
10 19 184.3168
11 22 136.7847
12 24 -27.7761
13 26 -152.1896
14 28 59.2097
15 30 60.7000
16 32 -73.1785
17 34 57.7680
18 36 53.4213
19 38 -28.4149
20 40 64.9300
21 42 -39.5014
22 44 77.1079
(Table 9C: Zoom lens group data)
Focal length of the group Lens configuration length Front principal point position Posterior principal point position
1 1 140.56785 22.40000 7.18213 14.08919
2 7 -49.01584 27.74810 11.11715 18.65388
3 17 55.60279 6.40000 1.11953 3.92297
4 19 101.72930 37.92000 34.91726 45.25012
5 36 -61.27816 4.01000 2.27736 4.10377
6 40 64.93002 4.20000 2.02806 3.94574
7 42 -81.84831 39.70000 -0.20157 3.25714
(Table 9D: Zoom lens group magnification)
Group starting surface wide-angle intermediate telephoto
1 1 0.00000 0.00000 0.00000
2 7 -0.68916 -1.02790 -1.80069
3 17 -0.65303 -0.72853 -0.59859
4 19 0.65527 0.64608 0.68098
5 36 2.60136 2.40563 2.28332
6 40 0.46061 0.50299 0.56174
7 42 1.45864 1.45822 1.45835
(Numerical Example 4)
The numerical embodiment 4 of the zoom lens system corresponding to the fourth embodiment shown in FIG. 7 is shown below. Specifically, as Numerical Example 4, surface data (Table 10), aspherical data (Table 11), and various data in the infinity in-focus state are shown in (Table 12A) to (Table 12D).

(Table 10: Surface data)
Face number rd nd vd
Paraboloid ∞
1 112.14470 2.40000 1.90366 31.3
2 81.82260 1.40000
3 81.60250 9.50720 1.43700 95.1
4-3497.51790 0.20000
5 99.50410 10.51410 1.43700 95.1
6 1686.59580 Variable
7 182.85300 6.00010 1.75520 27.5
8-256.98530 0.32110
9 -574.84080 1.50000 1.70154 41.1
10 38.86560 8.96550
11 -284.44910 1.50000 1.49700 81.6
12 41.26090 0.01000 1.56732 42.8
13 41.26090 4.46010 1.90366 31.3
14 162.74970 4.61500
15 -49.82840 1.50000 1.62299 58.1
16 -271.91750 Variable
17 79.61000 5.00900 1.83400 37.3
18 -155.95020 1.00000
19 46.62130 3.50000 1.49700 81.6
20 106.00950 2.70000
21 (Aperture) ∞ 3.00000
22 -545.78210 6.60380 1.43700 95.1
23 -44.29830 0.01000 1.56732 42.8
24-44.29830 1.20000 1.84666 23.8
25 53.63890 2.40000
26 40.47650 1.50000 1.84666 23.8
27 30.58110 0.01000 1.56732 42.8
28 30.58110 6.00000 1.49700 81.6
29 247.48790 0.30000
30 * 88.75590 5.40000 1.58699 59.5
31 * -61.48970 3.00000
32 -51.39790 1.40000 1.58144 40.9
33 -279.49130 0.01000 1.56732 42.8
34 -279.49130 3.70000 1.84666 23.8
35 -45.55050 Variable
36 -1582.98910 3.37950 1.86966 20.0
37 -43.84120 0.01000 1.56732 42.8
38 -43.84120 0.70000 1.70154 41.1
39 38.76340 Variable
40 96.79470 4.73480 1.72825 28.3
41 -87.12640 Variable
42 -48.64120 1.40000 1.84666 23.8
43 125.55010 0.20000
44 43.22890 4.31970 1.65844 50.9
45 114.19170 31.00000
46 ∞ 2.10000 1.51680 64.2
47 ∞ BF
Image plane ∞
(Table 11: Aspherical data)
30th page
K = 1.25623E + 01, A4 = -3.63281E-06, A6 = -8.21499E-09, A8 = 9.56442E-11
A10 = -2.82844E-13, A12 = 4.08799E-16, A14 = 9.50559E-19
31st page
K = -1.84110E + 00, A4 = 2.47963E-06, A6 = -4.000963E-09, A8 = 6.19911E-11
A10 = -2.42940E-14, A12 = -5.02635E-16, A14 = 2.32780E-18
(Various data in infinity in focus)
(Table 12A: Various data)
Zoom ratio 2.67241
Wide-angle medium telephoto focal length 72.4498 119.9979 193.6156
F number 2.89921 2.91360 2.92705
Angle of view 16.8894 10.1319 6.2809
Image height 21.6300 21.6300 21.6300
Lens overall length 229.9997 229.9996 229.9996
BF 1.0900 1.0900 1.0900
d6 1.3025 28.0338 49.8241
d16 49.5216 22.7904 1.0000
d35 2.4000 4.7354 2.6403
d39 23.4616 20.5600 24.6055
d41 4.7441 5.3101 3.3598
Entrance pupil position 89.6041 153.2780 216.6798
Exit pupil position -91.4492 -89.2564 -92.7287
Front principal point position 104.6632 111.9143 6.2153
Rear principal point position 157.5609 109.9827 36.4265
(Table 12B: Single lens data)
Lens start surface focal length
1 1 -347.9529
2 3 182.6231
3 5 241.4868
4 7 142.3023
5 9 -51.8395
6 11 -72.3927
7 13 60.1195
8 15 -98.1816
9 17 63.8124
10 19 164.2327
11 22 109.8832
12 24 -28.4954
13 26 -158.7797
14 28 69.5680
15 30 62.7166
16 32 -108.5618
17 34 63.8126
18 36 51.7947
19 38 -29.2234
20 40 63.6541
21 42 -41.2560
22 44 103.1558
(Table 12C: Zoom lens group data)
Focal length of the group Lens configuration length Front principal point position Posterior principal point position
1 1 151.01504 24.02130 5.89093 12.98879
2 7 -48.29943 28.87180 13.30140 20.72990
3 17 47.40103 46.74280 21.79787 20.96308
4 36 -67.56068 4.08950 2.25037 4.11657
5 40 63.65407 4.73480 1.45765 3.42275
6 42 -67.87039 39.01970 0.74047 3.86678
(Table 12D: Zoom lens group magnification)
Group starting surface wide-angle intermediate telephoto
1 1 0.00000 0.00000 0.00000
2 7 -0.62662 -0.95931 -1.69130
3 17 -0.42848 -0.47419 -0.41753
4 36 2.23126 2.21887 2.17666
5 40 0.52198 0.51329 0.54352
6 42 1.53416 1.53372 1.53463
Since the above-described embodiment is for exemplifying the technology in the present disclosure, various changes, replacements, additions, omissions, etc. can be made within the scope of claims or the equivalent scope thereof.
(Corresponding value of condition)
As described above, the zoom lens systems according to the first to fourth embodiments have been specifically implemented in the numerical embodiments 1 to 4.

Below, the values corresponding to the above conditions (1) to (4) in each numerical example are shown in (Table 13).

(Table 13: Corresponding values of conditions)

The zoom lens system according to the present disclosure includes a digital still camera, an interchangeable lens type digital camera, a digital video camera, a camera of a mobile phone device, a PDA (Personal Digital Assistant) camera, a surveillance camera in a surveillance system, a Web camera, an in-vehicle camera, and the like. It is applicable to. In particular, the present disclosure is suitable for zoom lens systems that require high image quality, such as digital still camera systems and digital video camera systems.

G1 1st lens group G2 2nd lens group G3 3rd lens group G4 4th lens group G5 5th lens group G6 6th lens group G7 7th lens group L1 1st lens element L2 2nd lens element L3 3rd lens element L4 4th lens element L5 5th lens element L6 6th lens element L7 7th lens element L8 8th lens element L9 9th lens element L10 10th lens element L11 11th lens element L12 12th lens element L13 13th lens element L14 14th lens element L15 15th lens element L16 16th lens element L17 17th lens element L18 18th lens element L19 19th lens element L20 20th lens element L21 21st lens element L22 22nd lens element A Aperture aperture P parallel Flat plate S image plane 100 Imaging device 101 Zoom lens system 102 Imaging element 104 Housing 200 Camera system 201 Camera body 202 Imaging element 203 Monitor 204 Camera mount 205 Finder 300 Interchangeable lens device 301 Zoom lens 302 Lens mount 304 Lens mount

Claims (8)

From the object side to the image side,
The first lens group with positive power and
The second lens group with negative power and
Consists of a subsequent lens group
The trailing lens group moves along the optical axis when focusing from the infinity in-focus state to the close object in-focus state.
The first focus lens group with negative power and
A second focus lens group having a positive power, which is adjacent to the image side of the first focus lens group, is provided.
When zooming from the wide-angle end to the telephoto end, the distance between each lens group changes, and the first lens group is fixed to the image plane.
Satisfy the following condition (1)
−0.23 <f2 / TTL <−0.15 ・ ・ ・ (1)
here,
TTL: Overall optical length at the telephoto end,
f2: Focal length of the second lens group,
Is,
Zoom lens system. The second lens group is arranged in order from the object side.
Lens elements with positive power and
Lens elements with negative power and
Lens elements with negative power and
Lens elements with positive power and
Lens elements with negative power and
Consists of
The zoom lens system according to claim 1. The first focus lens group satisfies the following condition (2).
-3.2 <(1-β1 x β1) x (β2 x β2) <-2.4 ... (2)
here,
β1: Horizontal magnification at the telephoto end of the first focus lens group,
β2: Horizontal magnification at the telephoto end of the image-side optical system from the first focus lens group,
Is,
The zoom lens system according to claim 1 or 2. The first focus lens group has a lens element having a positive power and a lens element having a negative power.
The second focus lens group comprises one lens element having a positive power.
The zoom lens system according to any one of claims 1 to 3. The subsequent lens group includes an aperture diaphragm and
The lens element adjacent to the object side of the aperture diaphragm and the lens element adjacent to the image side of the aperture diaphragm have positive power.
Satisfy the following conditions (3) and (4),
vd1> 65 ... (3)
vd2> 65 ... (4)
here,
vd1: Abbe number of lens elements adjacent to the object side of the aperture diaphragm,
vd2: Abbe number of lens elements adjacent to the image side of the aperture diaphragm,
Is,
The zoom lens system according to any one of claims 1 to 4. The zoom lens system according to any one of claims 1 to 5.
With a lens mount,
It is detachably connected to the camera body including an image sensor that receives an optical image and converts it into an electrical image signal via the lens mount.
Forming the optical image on the image sensor,
Lens barrel. An imaging device that converts an optical image of an object into an electrical image signal and displays and stores the converted image signal.
The zoom lens system according to any one of claims 1 to 5, which forms an optical image of the object.
An image pickup device that converts the optical image formed by the zoom lens system into the electrical image signal is provided.
Imaging device. An interchangeable lens device including the zoom lens system according to any one of claims 1 to 5 is detachably connected to the interchangeable lens device via a camera mount portion, and an optical image formed by the zoom lens system is formed. A camera body including an image pickup element that receives light and converts it into an electrical image signal.
The interchangeable lens device forms the optical image on the image sensor.
Camera system.

Images