JP2013057801A - Zoom lens and imaging apparatus including the same - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a zoom lens which is a positive lead type zoom lens, has a high zoom ratio, and can obtain excellent optical characteristics over the entire zoom range, while miniaturizing the entire system.SOLUTION: A zoom lens comprises, in order from an object side to an image side, a first lens group having positive refractive power, a second lens group having negative refractive power, a third lens group having positive refractive power, a fourth lens group having negative refractive power, and a fifth lens group having positive refractive power. In the zoom lens, the respective lens groups are moved so as to change intervals between the respective lens groups in zooming. The first lens group comprises, in order from the object side to the image side, a negative lens and a positive lens; and the movement amount m1 of the first lens group in zooming from a wide angle end to a telephoto end, the focal length f1 of the first lens group, and the focal length fw of the entire system at the wide angle end are respectively set properly.

Description

  The present invention relates to a zoom lens and an image pickup apparatus having the same, and is suitable for a photographing lens such as a digital camera, a video camera, a TV camera, a surveillance camera, and a silver salt photography camera.

  In recent years, as imaging devices such as digital cameras and video cameras have become smaller and more functional, imaging lenses used therefor are small zoom lenses that have a high zoom ratio and high optical performance over the entire zoom range. It is required to be.

  As a small zoom lens having a high zoom ratio, a so-called positive lead type zoom lens in which a lens group having a positive refractive power is disposed closest to the object side is known. As a positive lead type zoom lens, it consists of first to fifth lens groups having positive, negative, positive, negative, and positive refractive powers in order from the object side to the image side. A zoom lens having a configuration is known. In this zoom type five-group zoom lens, a small zoom lens is known in which the first lens group is composed of two lenses, a negative lens and a positive lens (Patent Document 1).

JP 2003-255228 A

  A positive lead type zoom lens is relatively easy to achieve a high zoom ratio while reducing the size of the entire system. On the other hand, in order to reduce the size of the imaging device and increase the zoom ratio of the zoom lens used therefor, a retractable type that reduces the distance between the lens groups to a different distance from the shooting state when not in use (when not shooting). Is used. According to this, the projection amount of the lens from the camera body can be reduced, and the image pickup apparatus can be reduced in size.

  Generally, when the number of lenses in each lens group constituting the zoom lens is large, the length in the optical axis direction of each lens group becomes long. Further, when the moving amount of each lens unit in zooming and focusing is large, the total lens length becomes long. As a result, it is difficult to obtain a desired retractable length, and it is difficult to use the retractable zoom lens.

  In zoom lenses used in many imaging devices, it is an important issue that the entire lens system is downsized and has a predetermined zoom ratio and has good optical performance over the entire zoom range. Yes. In order to solve this problem, it is necessary to appropriately set the movement condition of each lens group accompanying zooming, the refractive power of each lens group, the lens configuration of each lens group, and the like. For example, regarding the miniaturization of a zoom lens, if the refractive power of each lens group is increased, the amount of movement of each lens group during zooming is reduced, and the overall length of the lens can be easily shortened.

  However, if the refractive power of each lens group is simply increased, aberration fluctuations accompanying zooming increase, and it becomes difficult to correct this well. In particular, in the above-described positive lead type five-unit zoom lens, in order to obtain a high zoom ratio and high optical performance over the entire zoom range while reducing the size of the entire system, the lens configuration of each lens unit is appropriately set. Setting is important. For example, it is important to appropriately set the refractive power of the first lens group, the amount of movement during zooming, and the like. If the configuration of the first lens group is inappropriate, it is difficult to obtain high optical performance over the entire zoom range while reducing the size of the entire system.

  An object of the present invention is to provide a zoom lens capable of obtaining a good optical characteristic in the entire zoom range with a high zoom ratio while reducing the size of the entire system in a positive lead type zoom lens, and an imaging apparatus having the same.

The zoom lens according to the present invention includes, 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 having a negative refractive power. In the zoom lens that includes a fourth lens group and a fifth lens group having a positive refractive power, and in which each lens group moves so that the distance between the lens groups changes during zooming,
The first lens group includes a negative lens and a positive lens from the object side to the image side, and the amount of movement of the first lens group during zooming from the wide-angle end to the telephoto end is m1, and the focal length of the first lens group is When the focal length of the entire system at f1, the wide angle end is fw,
4.2 <m1 / fw <7.0
5.0 <f1 / fw <13.0
It is characterized by satisfying the following conditions.

  According to the present invention, in a positive lead type zoom lens, it is possible to obtain a zoom lens capable of obtaining good optical characteristics in the entire zoom range with a high zoom ratio while reducing the size of the entire system.

Cross-sectional view of the zoom lens of Embodiment 1 at the wide-angle end (A), (B), (C) Aberration diagrams at the wide-angle end, the intermediate zoom position, and the telephoto end of Example 1. Lens cross-sectional view at the wide-angle end of the zoom lens according to Embodiment 2 (A), (B), (C) Aberration diagrams at the wide-angle end, the intermediate zoom position, and the telephoto end of Example 2. Lens cross-sectional view at the wide-angle end of the zoom lens according to Embodiment 3 (A), (B), (C) Aberration diagrams at the wide-angle end, the intermediate zoom position, and the telephoto end of Example 3. Lens cross-sectional view at the wide-angle end of the zoom lens according to Embodiment 4 (A), (B), (C) Aberration diagrams at the wide-angle end, the intermediate zoom position, and the telephoto end of Example 4. Explanatory drawing of the paraxial refractive power arrangement of the zoom lens of the present invention Schematic diagram of main parts of an imaging apparatus of the present invention

  Hereinafter, preferred embodiments of the present invention will be described in detail with reference to the accompanying drawings. The zoom lens according to the present invention includes, 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 having a negative refractive power. The fourth lens group includes a fifth lens group having a positive refractive power. Then, each lens group moves so that the interval between the lens groups changes during zooming.

  1A, 1B, and 1C are lens cross-sectional views at the wide-angle end (short focal length end), the intermediate zoom position, and the telephoto end (long focal length end) according to the first embodiment. 2A, 2B, and 2C are aberration diagrams of Example 1 at the wide-angle end, the intermediate zoom position, and the telephoto end. Example 1 is a zoom lens having a zoom ratio of 9.56 and an aperture ratio of about 3.25 to 6.11. 3A, 3B, and 3C are lens cross-sectional views at the wide-angle end, the intermediate zoom position, and the telephoto end of the second embodiment. 4A, 4B, and 4C are aberration diagrams of Example 2 at the wide-angle end, the intermediate zoom position, and the telephoto end. The second embodiment is a zoom lens having a zoom ratio of 7.65 and an aperture ratio of about 3.03 to 6.05.

  5A, 5B, and 5C are lens cross-sectional views at the wide-angle end, the intermediate zoom position, and the telephoto end of the third embodiment. 6A, 6B, and 6C are aberration diagrams of Example 3 at the wide-angle end, the intermediate zoom position, and the telephoto end. Example 3 is a zoom lens having a zoom ratio of 11.48 and an aperture ratio of about 3.73 to 6.05. 7A, 7B, and 7C are lens cross-sectional views at the wide-angle end, the intermediate zoom position, and the telephoto end of the fourth embodiment. 8A, 8B, and 8C are aberration diagrams of Example 4 at the wide-angle end, the intermediate zoom position, and the telephoto end. The fourth embodiment is a zoom lens having a zoom ratio of 11.48 and an aperture ratio of about 3.50 to 6.05.

  FIG. 9 is an explanatory diagram of a movement locus accompanying zooming of each lens unit in the paraxial refractive power arrangement of the zoom lens according to the present invention. FIG. 9 (W) shows the wide-angle end, and FIG. 9 (T) shows the telephoto end. FIG. 10 is a schematic diagram of a main part of a digital still camera (imaging device) including the zoom lens of the present invention.

  The zoom lens of each embodiment is a photographic lens system used in an imaging apparatus such as a video camera, a digital still camera, a silver salt film camera, or a TV camera. In addition, the zoom lens of each embodiment can also be used as a projection optical system for a projection apparatus (projector). In the lens cross-sectional view, the left side is the object side (front), and the right side is the image side (rear). In the lens cross-sectional view, when i is the order of the lens group from the object side, Li indicates the i-th lens group.

  SP is an aperture stop. G is an optical block corresponding to an optical filter, a face plate, a low-pass filter, an infrared cut filter, or the like. IP is the image plane. The image plane IP corresponds to an imaging plane of a solid-state imaging device (photoelectric conversion device) such as a CCD sensor or a CMOS sensor when a zoom lens is used as a photographing optical system of a video camera or a digital camera. When a zoom lens is used as a photographing optical system of a silver salt film camera, it corresponds to a film surface. Arrows indicate the movement trajectory of each lens unit during zooming (variation) from the wide-angle end to the telephoto end.

  In the spherical aberration diagram, Fno is an F number. D is a d-line (wavelength 587.6 nm) and g is a g-line (wavelength 435.8 nm). In the astigmatism diagram, ΔM and ΔS are the sagittal image surface and the meridional image surface at the d-line. Distortion is shown for the d-line. The lateral chromatic aberration diagram is the g-line. ω is a shooting half angle of view. In each of the following embodiments, the wide-angle end and the telephoto end refer to zoom positions when the zoom lens group is positioned at both ends of a range in which the zoom lens unit can move on the optical axis.

  The zoom lens according to each embodiment includes, in order from the object side to the image side, a first lens unit L1 having a positive refractive power, a second lens unit L2 having a negative refractive power, an aperture stop SP1, and a third lens having a positive refractive power. The lens unit L3 includes a fourth lens unit L4 having a negative refractive power and a fifth lens unit L5 having a positive refractive power.

  As shown in FIG. 9, during zooming from the wide-angle end to the telephoto end, the first lens unit L1 moves along a locus convex toward the image side. The second lens unit L2 moves along a locus convex toward the image side. The third lens unit L3 moves to the object side. The fourth lens unit L4 moves to the object side. The fifth lens unit L5 moves along a locus convex toward the object side. The aperture stop SP moves independently of each lens unit or integrally with the third lens unit L3.

  At this time, in each lens group, the distance between the first lens group L1 and the second lens group L2 is increased and the distance between the second lens group L2 and the third lens group L3 is decreased at the telephoto end compared to the wide-angle end. The distance between the third lens group and the fourth lens group L4 increases. Furthermore, the fourth lens unit L4 and the fifth lens unit L5 move so that the distance between them increases.

  In the zoom lens of each embodiment, the first lens unit L1 is moved so as to be located on the object side at the telephoto end compared to the wide-angle end. Thereby, a large zoom ratio can be obtained while shortening the total lens length at the wide-angle end.

  Further, when zooming from the wide-angle end to the telephoto end, the first lens unit L1 is moved toward the image side, and then moved back and forth to the object side, thereby taking a reciprocal or substantially reciprocal movement locus. Is shortened. In this way, the effective area of the effective diameter of the front lens determined in the intermediate zoom area is reduced to reduce the effective diameter of the front lens. Further, during zooming, the second lens unit L2 moves along a locus convex toward the image side, thereby giving the second lens unit L2 a large zooming effect.

  Further, during zooming, the third lens unit L3 has a large zooming effect by moving the third lens unit L3 so that it is positioned closer to the object side at the telephoto end than at the wide angle end. Further, during zooming, the fourth lens unit L4 is moved closer to the object side at the telephoto end than at the wide-angle end, thereby securing a focus space for the fifth lens unit L5 as the focus lens unit. During zooming from the wide-angle end to the telephoto end, the fifth lens unit L5 moves along a locus convex toward the object side. Further, a rear focus type is employed in which the fifth lens unit L5 is moved on the optical axis to perform focusing.

  By moving the aperture stop SP disposed between the second lens unit L2 and the third lens unit L3 independently of each lens unit or integrally with the third lens unit during zooming from the wide-angle end to the telephoto end, The effective diameter of the ball is reduced. In particular, by moving the aperture stop SP toward the object side during zooming from the wide-angle end to the telephoto end, the effective diameter of the front lens is reduced in widening the angle of view.

  By moving the fifth lens unit L5 in the zooming with a convex locus on the object side, the space between the fourth lens unit L4 and the fifth lens unit L5 is effectively used, and the entire lens length is effectively shortened. Has been achieved. The fifth lens unit L5 corrects image plane fluctuations accompanying zooming. At the telephoto end, when focusing from an object at infinity to an object at a short distance, the fifth lens unit L5 is extended forward.

  Next, the lens configuration of each lens group will be described. Hereinafter, in order from the object side to the image side, the first lens unit L1 includes a meniscus negative eleventh lens (negative lens) having a convex surface on the object side, and the curvature (1 / R) has a twelfth lens (positive lens) having a strong (large) positive refractive power. Further, it is constituted by a cemented lens. Here, that the curvature is tight means that the absolute value of the curvature is large.

  The second lens unit L2 has a negative refractive power of the 21st lens having a negative refractive power whose image side surface is harder than the object side, and a negative refractive power having a negative refractive power whose both lens surfaces have a concave curvature on the image side compared to the object side. 22 lenses. Further, the object side surface has a curvature that is tighter than that of the image side, and a 23rd lens having a positive refractive power.

  The third lens unit L3 has a positive refractive power of the 31st lens having convex surfaces on both lens surfaces, a 32nd lens having a convex meniscus shape on the object side and a meniscus negative refractive power having a convex surface on the object side. A 33rd lens is included. Further, the 34th lens has a positive refractive power in which the curvature of the image side surface is stronger than that of the object side. The 32nd lens and the 33rd lens are cemented. The object side surface of the 31st lens on the object side of the third lens unit L3 has an aspherical shape, so that the aberration can be corrected well while shortening the amount of movement of the third lens unit L3 during zooming. Yes.

  The fourth lens unit L4 is a forty-first lens having a positive refractive power with a strong refractive power compared to the object side and a forty-second lens having a negative refractive power with a positive curvature on the object side compared to the image side. It is comprised by the cemented lens which joined. The fifth lens unit L5 includes a 51st lens having a positive refractive power. In general, there are many 5-group zoom lenses composed of first to fifth lens groups having positive, negative, positive, negative, and positive refractive powers with a zoom ratio of about 8 to 12 times, and the first lens group is composed of three lenses. .

  On the other hand, in the present invention, in order to reduce the size of the entire lens system, the first lens unit L1 is composed of two lenses while ensuring desired optical performance. In each embodiment, the amount of movement and optical power (refractive power) during zooming of the first lens unit L1 are appropriately set in order to achieve downsizing of the entire lens system while ensuring a high zoom ratio at a wide angle of view. doing. Specifically, the amount of movement of the first lens unit L1 during zooming from the wide-angle end to the telephoto end is set to m1 (the sign of the amount of movement is positive when the object is located at the telephoto end compared to the wide-angle end, toward the image side) The position is negative). The focal length of the first lens unit L1 is f1, and the focal length of the entire system at the wide angle end is fw.

At this time,
4.2 <m1 / fw <7.0 (1)
5.0 <f1 / fw <13.0 (2)
Is satisfied.

  Next, the technical meaning of each conditional expression will be described. Conditional expression (1) relates to the ratio of the focal length of the entire system at the wide-angle end to the amount of movement of the first lens unit L1 during zooming from the wide-angle end to the telephoto end.

  If the upper limit of conditional expression (1) is exceeded and the amount of movement of the first lens unit L1 becomes too large, the total lens length (distance from the first lens surface to the image plane) increases at the telephoto end. As the number of lens barrels increases, the entire lens system becomes larger. If the lower limit of conditional expression (1) is exceeded and the amount of movement of the first lens unit L1 becomes too small, the optical power of the first lens unit L1 must be increased in order to obtain a predetermined zoom ratio. It becomes difficult to correct the fluctuation of the field curvature in the zoom range. Further, the total length at the wide-angle end increases and the effective diameter of the front lens increases.

  Conditional expression (2) relates to the ratio of the focal length of the entire system at the wide angle end to the focal length of the first lens unit L1. If the upper limit of conditional expression (2) is exceeded and the focal length of the first lens unit L1 becomes long and the optical power is too low, the variation in chromatic aberration during zooming increases, making it difficult to correct this. If the lower limit of conditional expression (2) is exceeded and the focal length of the first lens unit L1 is shortened and the optical power is too strong, coma in the intermediate zoom range increases during zooming, and this correction becomes difficult. . More preferably, the numerical ranges of conditional expressions (1) and (2) are set as follows.

4.3 <m1 / fw <6.5 (1a)
9.0 <f1 / fw <12.8 (2a)
In each embodiment, the following conditions are more preferably satisfied. The focal length of the entire system at the telephoto end is ft, and the focal length of the fourth lens unit L4 is f4. The fourth lens unit L4 includes, in order from the object side to the image side, a forty-first lens having a positive refractive power and a forty-second lens having a negative refractive power. The focal length of the forty-first lens is f41. The imaging magnifications of the third lens unit L3 at the wide-angle end and the telephoto end are β3w and β3t, respectively. At this time, it is preferable to satisfy one or more of the following conditions.

−0.5 <f4 / ft <−0.2 (3)
−2.5 <f41 / f4 <−0.4 (4)
1.6 <β3t / β3w <3.6 (5)
In a five-unit zoom lens composed of positive, negative, positive, negative, and positive refractive power lens groups, when a camera shake correction function (anti-vibration function) is added, the third lens unit L3 is shifted in the direction perpendicular to the optical axis. It is desirable in terms of sensitivity to perform correction.

  However, in each embodiment, the first lens unit L1 has a two-lens configuration in order to reduce the size of the entire system in the total. For this reason, in order to satisfactorily correct aberrations in the entire system, it is necessary to configure the third lens unit L3 with four lenses. When the third lens unit L3 is used for image stabilization, the weight of the third lens unit L3 is required. However, the mechanical mechanism is easy to enlarge.

  Therefore, in the zoom lens of the present invention, the fourth lens unit L4 is shifted so as to have a component in the direction perpendicular to the optical axis, thereby performing vibration isolation. In order to perform the image stabilization with the fourth lens unit L4, unless the refractive power of the fourth lens unit L4 is increased to some extent, the driving amount at the time of image stabilization increases, and the mechanical mechanism tends to be enlarged. For this reason, it is preferable to set the focal length of the fourth lens unit L4 so as to satisfy the conditional expression (3).

  Further, when the fourth lens unit L4 performs image stabilization, it is necessary to reduce the occurrence of chromatic aberration during image stabilization. For this reason, the curvature of the lens surface on the object side is tighter than that of the 41st lens having the positive refractive power and the image side on the image side compared to the object side in the configuration of the fourth lens unit L4. It is composed of a cemented lens in which a forty-second lens having a negative refractive power is cemented. Furthermore, as a condition for reducing the occurrence of chromatic aberration during image stabilization, the optical power of the 41st lens is appropriately set. Specifically, it is preferable to set as in conditional expression (4).

  The first lens unit L1 is composed of two lenses, and in order to correct aberrations satisfactorily while ensuring a high zoom ratio, the aberration variation tends to increase, so the variable magnification sharing of the second lens unit L2 is reduced. It is desirable to increase the variable power sharing of the third lens unit L3. The third lens unit L3 is a main variable power lens unit, and it is desirable that the variable power distribution of the third lens unit L3 satisfies the conditional expression (5). In order to satisfactorily correct aberrations while satisfying conditional expression (5), the third lens unit L3 is preferably composed of four lenses.

  In each embodiment, the third and fourth lens units L3 and L4 are appropriately set as described above, so that satisfactory aberration correction can be performed even if the third and fourth lens units L3 and L4 are configured by two lenses of the first lens unit L1. ing. Further, since the number of lenses is reduced, it is easy to shorten the overall length of the lens when retracted.

  Next, the technical meaning of each embodiment will be described. Conditional expression (3) relates to the ratio of the focal length of the entire system at the telephoto end to the focal length of the fourth lens unit L4. If the upper limit of conditional expression (3) is exceeded and the focal length of the fourth lens unit L4 becomes too long, the shift amount of the fourth lens unit L4 for image stabilization becomes large and the mechanical system becomes large. If the lower limit of conditional expression (3) is exceeded and the focal length of the fourth lens unit L4 becomes too short, it becomes difficult to correct coma at the periphery of the screen in the wide angle region.

  Conditional expression (4) relates to the ratio of the focal length of the fourth lens unit L4 to the focal length of the 41st lens. If the upper limit of conditional expression (4) is exceeded and the focal length of the forty-first lens becomes too long, chromatic aberration will increase during image stabilization and it will be difficult to correct this chromatic aberration. If the focal length of the forty-first lens becomes too short beyond the lower limit of conditional expression (4), a predetermined amount of edge thickness for the forty-first lens is ensured, so that the thickness of the fourth lens unit L4 increases and the fourth lens unit L4. The weight of the machine becomes heavier and the mechanical system becomes larger.

  Conditional expression (5) relates to the variable magnification sharing of the third lens unit L3. If the variable magnification share of the third lens unit L3 exceeds the upper limit of conditional expression (5), the amount of movement (stroke) increases during zooming, and the entire system becomes large. When the variable magnification share of the third lens unit L3 is reduced beyond the lower limit of the conditional expression (5), the variable magnification share of the second lens unit L2 increases, and the variation in field curvature during zooming increases, which is favorable. It will be difficult to correct. More preferably, the numerical ranges of conditional expressions (3) to (5) are set as follows.

−0.35 <f4 / ft <−0.22 (3a)
-1.9 <f41 / f4 <-0.7 (4a)
2.4 <β3t / β3W <3.0 (5a)
By configuring as described above, a zoom lens having a high optical performance over the entire zoom region while having a high zoom ratio of about 8 to 12 times while having a simple lens configuration and a compact entire system is obtained. Yes. In addition, the zoom lens can be stored compactly when retracted.

  In each embodiment, an anti-vibration mechanism that corrects image blur is configured by shifting the entire fourth lens unit L4 so as to have a component in a direction perpendicular to the optical axis. Image blur may be corrected by shifting so as to have a component perpendicular to the optical axis.

  Next, an embodiment of a digital camera (imaging device) using the zoom lens of the present invention as a photographing optical system will be described with reference to FIG. In FIG. 10, 20 is a digital camera body, 21 is a photographing optical system constituted by any of the zoom lenses of the first to fifth embodiments, and 22 is an image sensor such as a CCD that receives a subject image by the photographing optical system 21. is there. Reference numeral 23 denotes recording means for recording a subject image received by the image sensor 22, and reference numeral 24 denotes a finder for observing the subject image displayed on a display element (not shown). The display element is constituted by a liquid crystal panel or the like, and a subject image formed on the image sensor 22 is displayed.

  Thus, by applying the zoom lens of the present invention to an imaging apparatus such as a digital camera, an imaging apparatus having a small size and high optical performance is realized.

  Hereinafter, specific numerical data of numerical examples 1 to 4 corresponding to the first to fourth examples will be described. In each numerical example, i indicates the number of the surface counted from the object side. ri is the radius of curvature of the i-th optical surface (i-th surface). di is the axial distance between the i-th surface and the (i + 1) -th surface. ndi and νdi are the refractive index and Abbe number of the material of the i-th optical member with respect to the d-line, respectively. The two surfaces closest to the image correspond to the glass block G.

  In each numerical example, r = 10 is a dummy surface used in design. The aspherical shape is the X axis in the optical axis direction, the H axis in the direction perpendicular to the optical axis, the light traveling direction is positive, R is the paraxial radius of curvature, K is the conic constant, and A4 to A10 are each aspherical coefficients. ,

It is expressed by the following formula. * Means a surface having an aspherical shape. “E-x” means 10 ^−x . BF is an air equivalent back focus. Table 1 shows the relationship between the above-described conditional expressions and numerical examples.

[Numerical Example 1]
Unit mm

Surface data surface number rd nd νd
1 34.245 0.80 1.84666 23.8
2 23.811 2.80 1.69680 55.5
3 -1748.038 (variable)
4 65.270 0.70 1.88300 40.8
5 5.502 2.55
6 -117.628 0.40 1.88300 40.8
7 14.877 0.30
8 * 9.539 1.80 2.00178 19.3
9 29.808 (variable)
10 ∞ 0.00
11 (Aperture) ∞ (Variable)
12 * 8.595 1.70 1.55332 71.7
13 * -17.009 0.20
14 4.341 1.60 1.48749 70.2
15 8.162 0.50 2.00069 25.5
16 4.039 0.70
17 * 133.120 1.20 1.55332 71.7
18 -8.233 (variable)
19 300.000 1.30 1.76182 26.5
20 -10.519 0.50 1.88300 40.8
21 13.205 (variable)
22 10.984 2.10 1.48749 70.2
23 -299.238 (variable)
24 ∞ 0.80 1.51633 64.1
25 ∞ 1.0
Image plane ∞

Aspheric data 8th surface
K = -4.13147e-001 A 4 = 2.53155e-005 A 6 = 1.29927e-007 A 8 = 7.39754e-008 A10 = -1.70753e-009

12th page
K = -5.95723e-001 A 4 = -1.94729e-004 A 6 = -3.00148e-006

Side 13
K = 2.56880e + 000 A 4 = 4.01510e-004

17th page
K = -5.47442e + 003 A 4 = 2.59737e-004 A 6 = -2.35217e-005

Various data Zoom ratio 9.56
Wide angle Medium telephoto focal length 4.41 16.03 42.16
F number 3.25 4.47 6.11
Angle of view 37.64 13.59 5.25
Image height 3.40 3.88 3.88
Total lens length 44.10 50.45 70.29
BF 3.92 11.09 6.89

d 3 0.76 12.23 24.89
d 9 12.91 1.64 1.15
d11 4.39 2.81 0.80
d18 1.26 1.48 3.01
d21 1.71 2.05 14.39
d23 2.39 9.55 5.36

Entrance pupil position 9.82 26.95 71.30
Exit pupil position -20.08 -24.64 -237.20
Front principal point position 13.30 32.97 106.00
Rear principal point position -3.41 -15.02 -41.15

Zoom lens group data group Start surface Focal length Lens configuration length Front principal point position Rear principal point position
1 1 52.97 3.60 -0.10 -2.18
2 4 -7.30 5.75 0.31 -4.01
3 10 ∞ 0.00 0.00 -0.00
4 12 8.36 5.90 0.27 -4.05
5 19 -13.18 1.80 1.00 -0.01
6 22 21.78 2.10 0.05 -1.36
7 24 ∞ 0.80 0.26 -0.26

[Numerical Example 2]

Unit mm

Surface data surface number rd nd νd
1 30.639 0.80 1.84666 23.8
2 20.891 2.70 1.69680 55.5
3 -1513.742 (variable)
4 * -745.323 0.70 1.84862 40.0
5 * 5.043 2.37
6 -158.448 0.40 1.80 400 46.6
7 19.702 0.30
8 9.592 1.50 1.94595 18.0
9 26.921 (variable)
10 ∞ 0.00
11 (Aperture) ∞ 0.60
12 * 7.735 1.60 1.55332 71.7
13 * -14.329 0.20
14 4.074 1.50 1.48749 70.2
15 8.138 0.50 2.00069 25.5
16 3.758 0.55
17 * 46.202 1.20 1.55332 71.7
18 -8.206 (variable)
19 -374.490 1.00 1.80809 22.8
20 -15.872 0.50 1.88300 40.8
21 10.540 (variable)
22 10.609 2.20 1.48749 70.2
23 -110.837 (variable)
24 ∞ 0.80 1.51633 64.1
25 ∞ 1.03
Image plane ∞

Aspheric data 4th surface
K = 1.23184e + 004 A 4 = 1.42396e-005

5th page
K = -5.42887e-001 A 4 = 3.44902e-004 A 6 = 1.44581e-005 A 8 = -6.11409e-008 A10 = 8.53111e-009

12th page
K = -1.18502e + 000 A 4 = -3.48462e-004 A 6 = -6.72611e-006

Side 13
K = 7.54046e + 000 A 4 = 4.48566e-004

17th page
K = 9.21258e + 001 A 4 = -3.20248e-004 A 6 = -3.93029e-005

Various data Zoom ratio 7.65

Focal length 4.41 14.57 33.73
F number 3.03 4.47 6.05
Angle of view 37.64 14.89 6.55
Image height 3.40 3.88 3.88
Total lens length 40.20 42.77 59.52
BF 3.02 7.42 5.81

d 3 0.76 9.42 20.84
d 9 14.61 2.69 1.00
d18 1.11 2.50 2.41
d21 2.08 2.12 10.83
d23 1.47 5.86 4.26

Entrance pupil position 9.60 21.91 57.02 32.54 14.39
Exit pupil position -12.65 -18.27 -76.66 -23.33 -15.51
Front principal point position 12.59 25.47 76.10 34.89 18.51
Rear principal point position -3.38 -13.54 -32.70 -20.70 -6.84

Zoom lens group data group Start surface Focal length Lens configuration length Front principal point position Rear principal point position
1 1 47.65 3.50 -0.10 -2.13
2 4 -7.05 5.27 0.05 -4.09
3 10 7.50 6.15 0.76 -3.79
4 19 -11.00 1.50 0.78 -0.03
5 22 19.98 2.20 0.13 -1.36
6 24 ∞ 0.80 0.26 -0.26

Single lens Data lens Start surface Focal length
1 1 -80.59
2 2 29.60
3 4 -5.90
4 6 -21.77
5 8 15.12
6 12 9.32
7 14 14.93
8 15 -7.40
9 17 12.69
10 19 20.48
11 20 -7.11
12 22 19.98
13 24 0.00

[Numerical Example 3]

Unit mm

Surface data surface number rd nd νd
1 33.556 0.80 1.84666 23.8
2 23.078 3.20 1.69680 55.5
3 962.402 (variable)
4 * 53.479 0.70 1.84862 40.0
5 * 5.528 2.74
6 -100.187 0.40 1.80 400 46.6
7 13.836 0.30
8 9.712 1.80 1.94595 18.0
9 28.239 (variable)
10 ∞ 0.00
11 (Aperture) ∞ (Variable)
12 * 9.302 1.70 1.55332 71.7
13 * -15.712 0.20
14 4.376 1.70 1.48749 70.2
15 8.465 0.50 2.00069 25.5
16 4.124 1.05
17 * 78.358 1.50 1.55332 71.7
18 -8.560 (variable)
19 300.000 2.00 1.69895 30.1
20 -6.239 0.50 1.88300 40.8
21 16.337 (variable)
22 11.299 2.30 1.48749 70.2
23 -166.862 (variable)
24 ∞ 0.80 1.51633 64.1
25 ∞ 1.00
Image plane ∞

Aspheric data 4th surface
K = -1.55557e + 002 A 4 = 5.10113e-005

5th page
K = 5.85337e-002 A 4 = -2.22079e-006 A 6 = -1.63063e-005 A 8 = 1.01933e-006 A10 = -2.81723e-008

12th page
K = -4.92078e + 000 A 4 = 7.28672e-004 A 6 = -1.10985e-005

Side 13
K = -7.09634e + 000 A 4 = 3.95904e-004

17th page
K = 2.35725e + 002 A 4 = 2.83482e-004 A 6 = -3.73972e-005

Various data Zoom ratio 11.48
Wide angle Medium telephoto focal length 4.41 17.60 50.59
F number 3.73 5.13 6.05
Angle of view 37.64 12.41 4.38
Image height 3.40 3.88 3.88
Total lens length 46.91 54.31 75.35
BF 3.91 11.11 5.46

d 3 0.76 14.00 27.86
d 9 15.14 3.34 1.00
d11 3.39 1.20 1.05
d18 0.62 1.46 2.98
d21 1.71 1.82 15.61
d23 2.38 9.58 3.94

Entrance pupil position 10.60 32.87 87.41
Exit pupil position -18.26 -22.87 -2427.65
Front principal point position 14.00 37.49 136.94
Rear principal point position -3.41 -16.61 -49.59

Zoom lens group data group Start surface Focal length Lens configuration length Front principal point position Rear principal point position
1 1 55.19 4.00 -0.25 -2.56
2 4 -7.25 5.94 0.49 -3.98
3 10 ∞ 0.00 0.00 -0.00
4 12 8.59 6.65 0.69 -4.60
5 19 -12.29 2.50 1.39 -0.05
6 22 21.80 2.30 0.10 -1.45
7 24 ∞ 0.80 0.26 -0.26

Single lens Data lens Start surface Focal length
1 1 -90.46
2 2 33.89
3 4 -7.31
4 6 -15.10
5 8 14.94
6 12 10.82
7 14 16.35
8 15 -8.53
9 17 14.03
10 19 8.77
11 20 -5.06
12 22 21.80
13 24 0.00

[Numerical Example 4]

Unit mm

Surface data surface number rd nd νd
1 35.241 0.80 1.84666 23.8
2 23.279 3.10 1.77250 49.6
3 241.672 (variable)
4 * 32.849 0.70 1.84862 40.0
5 5.641 3.05
6 -56.439 0.40 1.88300 40.8
7 13.528 0.30
8 10.482 1.80 1.92286 18.9
9 51.697 (variable)
10 ∞ 0.00
11 (Aperture) ∞ (Variable)
12 * 10.087 1.90 1.55332 71.7
13 * -10.707 0.20
14 4.324 1.80 1.48749 70.2
15 8.730 0.50 2.00069 25.5
16 3.965 1.05
17 * -46.222 1.20 1.55332 71.7
18 -10.856 (variable)
19 48.667 1.80 1.69895 30.1
20 -5.159 0.50 1.88300 40.8
21 17.091 (variable)
22 12.294 2.10 1.48749 70.2
23 -33.196 (variable)
24 ∞ 0.80 1.51633 64.1
25 ∞ 0.98
Image plane ∞

Aspheric data 4th surface
K = 2.04555e + 000 A 4 = -5.59435e-005 A 6 = 2.90922e-007

12th page
K = -3.61118e + 000 A 4 = -1.24148e-004 A 6 = -4.49259e-006

Side 13
K = -2.29546e + 000 A 4 = -1.14347e-004

17th page
K = -5.26126e + 000 A 4 = 5.36639e-004

Various data Zoom ratio 11.48
Wide angle Medium telephoto focal length 4.41 13.25 50.59
F number 3.50 4.58 6.05
Angle of view 37.64 16.30 4.38
Image height 3.40 3.88 3.88
Total lens length 48.45 51.49 74.98
BF 3.89 8.52 7.55

d 3 0.76 10.87 27.75
d 9 16.70 5.25 1.00
d11 3.39 1.73 0.85
d18 0.80 2.09 5.61
d21 1.70 1.83 11.02
d23 2.38 7.01 6.05

Entrance pupil position 10.95 26.65 86.22
Exit pupil position -18.59 -22.22 -401.88
Front principal point position 14.37 32.33 130.46
Rear principal point position -3.43 -12.28 -49.61

Zoom lens group data group Start surface Focal length Lens configuration length Front principal point position Rear principal point position
1 1 56.10 3.90 -0.47 -2.63
2 4 -7.44 6.25 0.61 -4.22
3 10 ∞ 0.00 0.00 -0.00
4 12 9.16 6.65 -0.65 -5.15
5 19 -13.90 2.30 1.48 0.13
6 22 18.69 2.10 0.39 -1.05
7 24 ∞ 0.80 0.26 -0.26

Single lens Data lens Start surface Focal length
1 1 -83.56
2 2 33.14
3 4 -8.12
4 6 -12.33
5 8 13.95
6 12 9.70
7 14 15.50
8 15 -7.66
9 17 25.33
10 19 6.77
11 20 -4.44
12 22 18.69
13 24 0.00

L1 1st lens group L2 2nd lens group L3 3rd lens group L4 4th lens group L5 5th lens group SP Aperture G Glass block IP Image surface

Claims (10)

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, a fourth lens group having a negative refractive power, and a positive lens In a zoom lens that is configured by a fifth lens unit having refractive power, and in which each lens unit moves so that the interval between the lens units changes during zooming,
The first lens group includes, in order from the object side to the image side, a negative lens and a positive lens. The amount of movement of the first lens group during zooming from the wide-angle end to the telephoto end is m1, and the first lens group When the focal length is f1, and the focal length of the entire system at the wide angle end is fw,
4.2 <m1 / fw <7.0
5.0 <f1 / fw <13.0
A zoom lens characterized by satisfying the following conditions: When the focal length of the entire system at the telephoto end is ft and the focal length of the fourth lens group is f4,
−0.5 <f4 / ft <−0.2
The zoom lens according to claim 1, wherein the following condition is satisfied. The fourth lens group includes, in order from the object side to the image side, a forty-first lens having a positive refractive power and a forty-second lens having a negative refractive power, and the focal length of the fourth lens group and the forty-first lens is determined. When f4 and f41, respectively,
−2.5 <f41 / f4 <−0.4
The zoom lens according to claim 1 or 2, wherein the following condition is satisfied.   4. The zoom lens according to claim 1, wherein the second lens group includes a negative lens, a negative lens, and a positive lens in order from the object side to the image side.   5. The zoom lens according to claim 1, wherein the third lens group includes a positive lens, a positive lens, a negative lens, and a positive lens in order from the object side to the image side.   The zoom lens according to any one of claims 1 to 5, wherein the fifth lens group includes a single positive lens.   The zoom according to any one of claims 1 to 6, further comprising an aperture stop that moves along a locus different from each lens group during zooming between the second lens group and the third lens group. lens. When the imaging magnifications of the third lens group at the wide-angle end and the telephoto end are β3w and β3t, respectively.
1.6 <β3t / β3w <3.6
The zoom lens according to claim 1, wherein the following condition is satisfied.   9. The zoom lens according to claim 1, wherein the fifth lens unit moves toward the object side during focusing from an infinitely distant object to a close object. 10.   An image pickup apparatus comprising: the zoom lens according to claim 1; and an image pickup element that receives an image formed by the zoom lens.