JP2012008601A - Zoom lens and imaging apparatus including the same - Google Patents

Abstract

PROBLEM TO BE SOLVED: To implement a zoom lens which has a high zoom ratio, is small-sized, and has high optical performance while having a large field angle at a wide angle end, and to implement an imaging apparatus including the zoom lens.SOLUTION: The zoom lens includes, in order from the object side to the image side, a first lens group having a positive refracting power, a second lens group having a negative refracting power, a third lens group having a positive refracting power, a fourth lens group having a negative refracting power, and a fifth lens group having a positive refracting power. During zooming from the wide angle end to a telephoto end, all the lens groups are moved so that an interval between the first lens group and the second lens group is increased and an interval between the third lens group and the fifth lens group is increased. Focal lengths of the second lens group, the fourth lens group, and the fifth lens group are properly set relative to a zoom ratio and a focal length of an entire system at the telephoto end, and lateral magnifications at the wide angle end and the telephoto end of the fifth lens group are properly set relative to the zoom ratio.

Description

  The present invention relates to a zoom lens and an image pickup apparatus having the same, and particularly to a zoom lens suitable for a still camera, a video camera, a digital still camera, a surveillance camera, and the like and an image pickup apparatus having the same.

  In recent years, digital still cameras and digital video cameras using solid-state imaging devices such as CCDs and CMOSs have become mainstream. Along with the increase in the number of pixels of the solid-state imaging device, an increasing number of optical systems that achieve high magnification while maintaining high optical performance.

  For example, Patent Document 1 proposes a zoom lens having a wide angle of view and a zoom ratio of about 10 times from a wide angle range to a telephoto range.

  Further, Patent Document 2 proposes a zoom lens having a zoom ratio of about 10 times from a wide-angle range to a telephoto range while being small.

JP 2003-255228 A JP 2007-47538 A

The zoom lens disclosed in Patent Document 1 has a large angle of view 2ω at the wide angle end of 76 °, a zoom ratio of about 10 times, and a high zoom ratio, but the total lens length at the telephoto end is relatively long.
Although the zoom lens disclosed in Patent Document 2 is small and has a zoom ratio of about 10 times and a high zoom ratio, the image plane variation of the meridional section during zooming from the wide-angle end to the telephoto end is large.

  An object of the present invention is to provide a zoom lens having a high zoom ratio, a small size, and high optical performance while increasing the angle of view at the wide-angle end, and an image pickup apparatus having the zoom lens.

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, A fourth lens group having a refractive power and a fifth lens group having a positive refractive power, and during the zooming from the wide-angle end to the telephoto end, the distance between the first lens group and the second lens group increases. A zoom lens in which all the lens groups move so that the distance between the third lens group and the fifth lens group is increased, wherein the focal length of the second lens group is f2, and the focal length of the fourth lens group. F4, the focal length of the fifth lens group is f5, the focal length of the entire system at the wide-angle end is fw, the focal length of the entire system at the telephoto end is ft, and the lateral length at the wide-angle end and the telephoto end of the fifth lens group is When the magnification is β5w and β5t, respectively and when,
0.01 ≦ (| f4 | / f5) /Z≦0.11
Z = ft / fw
0.01 ≦ | f2 | /ft≦0.2
0.1 ≦ (f5 / | f2 |) /Z≦0.25
0.01 ≦ (| β5t | / | β5w |) /Z≦0.14
It is characterized by satisfying the following conditions.

  According to the present invention, it is possible to realize a zoom lens having a high zoom ratio, a small size, and high optical performance and an image pickup apparatus having the same while increasing the angle of view at the wide angle end.

Lens cross-sectional view at the wide-angle end of the zoom lens according to Numerical Example 1 of the present invention Aberration diagram of zoom lens according to Numerical Example 1 of the present invention Lens cross-sectional view at the wide-angle end of the zoom lens according to Numerical Example 2 of the present invention Aberration diagram of zoom lens according to Numerical Example 2 of the present invention Lens cross-sectional view at the wide-angle end of the zoom lens according to Numerical Example 3 of the present invention Aberration diagram of zoom lens according to Numerical Example 3 of the present invention Lens cross-sectional view at the wide-angle end of the zoom lens according to Numerical Example 4 of the present invention Aberration diagram of zoom lens according to Numerical Example 4 of the present invention Lens cross-sectional view at the wide-angle end of the zoom lens according to Numerical Example 5 of the present invention Aberration diagram of zoom lens according to Numerical Example 5 of the present invention Lens cross-sectional view at the wide-angle end of a zoom lens according to Numerical Example 6 of the present invention Aberration diagram of zoom lens according to Numerical Example 6 of the present invention Lens cross-sectional view at the wide-angle end of the zoom lens according to Numerical Embodiment 7 of the present invention Aberration diagram of zoom lens according to Numerical Example 7 of the present invention Schematic diagram of main parts of an imaging apparatus of the present invention

  Embodiments of the zoom lens according to the present invention will be described below with reference to the drawings.

  The zoom lens of the present invention includes a first lens group having a positive refractive power, a second lens group having a negative refractive power, and a third lens group having a positive refractive power in order from the object side to the image side. And a fourth lens group having a negative refractive power and a fifth lens group having a positive refractive power.

  In the zoom lens of the present invention, all the lens units move during zooming from the wide-angle end to the telephoto end. At this time, each lens group has a larger distance between the first lens group L1 and the second lens group L2 and a larger distance between the third lens group L3 and the fifth lens group L5 at the telephoto end than at the wide angle end. Moving.

  As described above, when all the lens groups move during zooming from the wide-angle end to the telephoto end, both a high zoom ratio and a reduction in size can be achieved.

  That is, during zooming, zooming is performed by increasing the distance between the first lens unit L1 and the second lens unit L2, but by moving the third lens unit L3 as well, the entrance pupil at the telephoto end is appropriately adjusted. The lens diameter can be reduced.

  Further, by moving the third lens unit L3, it is possible to share the zooming action of the first lens unit L1 and the second lens unit L2. Therefore, during zooming, the amount of movement of the first lens unit L1 and the second lens unit L2 can be reduced, and the total lens length at the telephoto end (from the lens surface closest to the object side of the first lens unit L1 to the image plane). The distance on the optical axis to the IP) can be shortened.

The zoom ratio can be further increased by moving the fifth lens unit L5 during zooming. In order to achieve a high zoom ratio, it is preferable to increase the distance between the third lens unit L3 and the fifth lens unit L5 during zooming from the wide-angle end to the telephoto end.
When the focal length of the fourth lens unit L4 is f4, the focal length of the fifth lens unit L5 is f5, the focal length of the entire system at the wide angle end is fw, and the focal length of the entire system at the telephoto end is ft. The refractive powers of the fourth lens unit L4 and the fifth lens unit L5 are appropriately set so as to satisfy the following conditional expressions.
0.01 ≦ (| f4 | / f5) /Z≦0.11 (1)
Z = ft / fw
Conditional expression (1) defines the ratio of the refractive power of the fourth lens unit L4 and the fifth lens unit L5 to the zoom ratio Z in zooming.

  In the present invention, in order to achieve a high zoom ratio, the fourth lens group and the fifth lens group are moved during zooming. By appropriately setting the refractive powers of the fourth lens group and the fifth lens group, it is possible to simultaneously realize a high zoom ratio, high optical performance, and downsizing.

  When the lower limit of conditional expression (1) is exceeded, the image plane variation on the wide-angle side becomes large, and it becomes difficult to maintain high optical performance. Since the amount of movement of the fourth lens unit L4 during zooming increases, it is difficult to reduce the size.

  Further, when the upper limit of conditional expression (1) is exceeded, if the amount of movement during zooming of the fifth lens unit L5 is increased in order to achieve a high zoom ratio in order to increase the image plane variation on the telephoto side, It becomes difficult to reduce the size.

Furthermore, preferable requirements for the zoom lens of the present invention will be described in detail in the following description of embodiments.
FIG. 1 is a lens cross-sectional view at the wide-angle end (short focal length end) of a zoom lens according to Numerical Example 1 of the present invention.
FIG. 2 is an aberration diagram of the zoom lens according to Numerical Example 1 of the present invention.
FIG. 3 is a lens cross-sectional view at the wide-angle end of the zoom lens according to Numerical Example 2 of the present invention.
FIG. 4 is an aberration diagram of the zoom lens according to Numerical Example 2 of the present invention.
FIG. 5 is a lens cross-sectional view at the wide-angle end of the zoom lens according to Numerical Example 3 of the present invention.
FIG. 6 is an aberration diagram of the zoom lens according to Numerical Example 3 of the present invention.
FIG. 7 is a lens cross-sectional view at the wide-angle end of a zoom lens according to Numerical Example 4 of the present invention.
FIG. 8 is an aberration diagram of the zoom lens according to Numerical Example 4 of the present invention.
FIG. 9 is a lens cross-sectional view at the wide-angle end of the zoom lens according to Numerical Example 5 of the present invention.
FIG. 10 is an aberration diagram of the zoom lens according to Numerical Example 5 of the present invention.
FIG. 11 is a lens cross-sectional view at the wide-angle end of a zoom lens according to Numerical Example 6 of the present invention.
FIG. 12 is an aberration diagram of the zoom lens according to Numerical Example 6 of the present invention.
FIG. 13 is a lens cross-sectional view at the wide-angle end of the zoom lens according to Numerical Example 7 of the present invention.
FIG. 14 is an aberration diagram of the zoom lens according to Numerical Example 7 of the present invention.
FIG. 15 is a schematic diagram of a main part of the imaging apparatus of the present invention.

  The zoom lens according to each embodiment is a photographing lens system used in an imaging apparatus such as a video camera, a digital camera, or a silver salt film camera. In the lens cross-sectional view, the left side is the object side (front side), and the right side is the image side. (Rear).

  In the lens cross-sectional view, L1 is a first lens group having a positive refractive power (optical power = reciprocal of focal length), L2 is a second lens group having a negative refractive power, and L3 is a third lens group having a positive refractive power. , L4 is a fourth lens group having a negative refractive power, and L5 is a fifth lens group having a positive refractive power.

  SP is an F-number determining member (hereinafter also referred to as “aperture stop”) that functions as an aperture stop that determines (limits) an open F-number (Fno) light beam.

  IP is an image plane, and when used as an imaging optical system of a video camera or a digital still camera, an imaging plane of a solid-state imaging device (photoelectric conversion device) such as a CCD sensor or a CMOS sensor is arranged. Further, when used as a photographing optical system for a silver salt film camera, a photosensitive surface corresponding to the film surface is disposed.

  In the aberration diagrams of spherical aberration, the solid line and the two-dot chain line are the d line and the g line, respectively. The aberration diagram of astigmatism is based on the d-line, the solid line corresponds to the sagittal image plane, and the two-dot chain line corresponds to the meridional image plane. Distortion is represented by d-line, and lateral chromatic aberration is represented by g-line. Fno is the F number, ω is the half field angle, and h is the image height.

  The wide-angle end and the telephoto end are zoom positions when the zooming lens units are positioned at both ends of a range in which the zoom lens group can move on the optical axis.

  In the lens cross-sectional view, arrows indicate the movement trajectory of each lens group when zooming from the wide-angle end to the telephoto end.

  In each embodiment, during zooming from the wide-angle end to the telephoto end, the first lens unit L1 moves to the object side, the second lens unit L2 moves to the image side, and the third lens unit L3 moves to the object side. The fourth lens unit L4 moves along a locus convex toward the object side, and the fifth lens unit L5 moves toward the image side. Thus, in the zoom lens of each embodiment, all the lens groups move during zooming from the wide-angle end to the telephoto end.

  The lens configuration of the zoom lens of each example is as follows.

  The first lens unit L1 includes, in order from the object side to the image side, a cemented lens in which the object side surface is a convex surface and a meniscus negative lens and a positive lens are cemented together, and the object side surface is a convex surface and a meniscus shape positive lens. It is configured.

  The second lens unit L2 in Examples 1, 4 to 7, in order from the object side to the image side, the image side is a concave meniscus negative lens, a biconcave negative lens, and the object side surface is a convex meniscus. It consists of a positive lens with a shape. The second lens unit L2 of Examples 2 and 3 includes, in order from the object side to the image side, two negative meniscus lenses with a concave surface on the image side, a negative meniscus lens with a concave surface on the object side, and a positive lens with a convex surface on the object side It is made up of.

  As a result, with respect to the second lens unit L2, fluctuations in chromatic aberration due to zooming can be reduced while reducing the diameter of the front lens. Then, in the entire zoom range from the wide-angle end to the telephoto end, it is possible to satisfactorily correct field curvature fluctuations and spherical aberration at the telephoto end. In particular, astigmatism and distortion are corrected well at the wide-angle end.

  The third lens unit L3 includes, in order from Examples 1 to 4 to 7, from the object side to the image side, a biconvex positive lens, a meniscus negative lens having a concave surface on the image side, and a biconvex positive lens. Has been. The third lens unit L3 in Examples 2 and 3 includes, in order from the object side to the image side, a biconvex positive lens, a negative meniscus lens having a concave surface on the image side, a negative meniscus lens having a concave surface on the image side, and a biconvex lens. It is constituted by a cemented lens in which a positive lens having a shape is cemented.

  As described above, the third lens unit L3 includes one or more positive lenses including the positive lens disposed closest to the object side and one or more negative lenses, and is included in the third lens unit. At least one of them is preferably an aspheric lens in order to correct spherical aberration and curvature of field.

  The fourth lens unit L4 includes any one of a negative lens, a cemented lens in which two negative lenses are cemented, and a cemented lens in which a positive lens and a negative lens are cemented.

  The fifth lens unit L5 includes a positive lens having a convex surface on the image side, and a cemented lens in which a biconvex positive lens and a meniscus negative lens having a concave surface on the object side are cemented.

  Here, focusing may be performed by moving the fourth lens unit L4 or the fifth lens unit L5 in the optical axis direction. This is because variations in various aberrations accompanying focusing can be relatively reduced.

  For image stabilization, it is preferable to change the imaging position by moving all or part of the third lens group so as to have a component perpendicular to the optical axis. This is because the fluctuation of the decentration aberration is relatively small.

  As described above, in Examples 1 to 7, the ratio between the refractive powers of the fourth lens unit L4 and the fifth lens unit L5 and the ratio of the zoom ratio Z are appropriately set, and the conditional expression (1) is satisfied. ing. Thus, a zoom lens having a high zoom ratio, a small size, and high optical performance is obtained while increasing the angle of view at the wide-angle end.

  Hereinafter, more preferable conditions for solving various technical problems required for the zoom lens will be described.

First, when the focal length of the second lens unit L2 is f2, and the focal length of the fifth lens unit L5 is f5,
0.01 ≦ | f2 | /ft≦0.2 (2)
0.1 ≦ (f5 / | f2 |) /Z≦0.25 (3)
It is preferable to satisfy one or more of the following conditions.

  Conditional expression (2) defines a preferable numerical range of the focal length f2 of the second lens unit L2 by a ratio to the focal length ft of the entire system at the telephoto end.

  If the lower limit of conditional expression (2) is exceeded, the refractive power of the second lens unit L2 becomes too large, and the amount of aberration generated in the second lens unit L2 increases, and in particular, field curvature and astigmatism are greatly generated. Resulting in. In order to correct it satisfactorily, an additional number of lenses and an aspherical surface are required, which is not preferable from the viewpoint of manufacturing cost.

  Conversely, exceeding the upper limit of conditional expression (2) is advantageous in terms of aberration correction, but during zooming, the amount of movement of the second lens unit L2 must be increased, and the total lens length becomes longer. It is not preferable.

  Conditional expression (3) defines a preferable numerical range regarding the ratio of the focal lengths of the second lens unit L2 and the fifth lens unit L5 by the ratio of the wide-angle end to the telephoto end of the focal length of the entire system.

  Exceeding the lower limit of conditional expression (3) is not preferable because the zooming action of the second lens unit L2 becomes too weak, and the movement amount of the second lens unit L2 increases during zooming, resulting in a longer total lens length. .

  Further, the refractive power of the fifth lens unit L5 becomes too large, and the amount of aberration generated in the fifth lens unit L5 increases. In particular, the field curvature and astigmatism are greatly generated, which is not preferable.

  On the contrary, if the upper limit of conditional expression (3) is exceeded, the refractive power of the second lens unit L2 becomes too large, and the amount of aberration generated in the second lens unit L2 increases, and in particular, field curvature and astigmatism are reduced. It will occur greatly.

Second, when the lateral magnifications at the wide-angle end and the telephoto end of the third lens unit L3 are β3w and β3t, respectively, and the lateral magnifications at the wide-angle end and the telephoto end of the fifth lens unit L5 are β5w and β5t, respectively.
0.01 ≦ (β3t / β3w) /Z≦0.2 (4)
0.01 ≦ (| β5t | / | β5w |) /Z≦0.14 (5)
It is preferable to satisfy one or more of the following conditions. Z represents the zoom ratio (ft / fw).

  Conditional expression (4) defines the zooming action of the third lens unit L3.

  If the lower limit of conditional expression (4) is exceeded, the zooming action of the third lens unit L3 will weaken, and the refractive power of the second lens unit L2 will need to be increased, making it difficult to suppress image plane fluctuations during zooming.

  Conversely, exceeding the upper limit of conditional expression (4) is advantageous for downsizing the entire system, but is not preferable because it increases field curvature and astigmatism.

  Conditional expression (5) defines the zooming action of the fifth lens unit L5.

  If the lower limit of conditional expression (5) is exceeded, the zooming action of the fifth lens unit L5 will weaken, and the amount of movement of the fifth lens unit L5 will increase during zooming from the wide-angle end to the telephoto end, reducing the overall size. It becomes difficult to achieve.

  Conversely, exceeding the upper limit of conditional expression (5) is advantageous for downsizing the entire system, but is not preferable because it increases field curvature and astigmatism.

  The zoom lenses of Examples 1 to 7 satisfy the conditional expressions (2) to (5) described above at the same time. However, it is not always necessary to satisfy all the conditional expressions at the same time. By satisfying each conditional expression, the effect described in each conditional expression can be obtained.

More preferably, the numerical ranges of conditional expressions (1) to (5) are set as follows.
0.06 ≦ (| f4 | / f5) /Z≦0.108 (1a)
0.07 ≦ | f2 | /ft≦0.15 (2a)
0.104 ≦ (f5 / | f2 |) /Z≦0.241 (3)
0.05 ≦ (β3t / β3w) /Z≦0.19 (4a)
0.04 ≦ (| β5t | / | β5w |) /Z≦0.131 (5a)
Next, an embodiment of a digital still camera using a zoom lens as shown in each embodiment as a photographing optical system will be described with reference to FIG.

  In FIG. 15, reference numeral 20 denotes a camera body, and reference numeral 21 denotes a photographing optical system constituted by any of the zoom lenses described in the first to fourth embodiments. Reference numeral 22 denotes a solid-state imaging device (photoelectric conversion device) such as a CCD sensor or a CMOS sensor that receives a subject image formed by the photographing optical system 21 and is built in the camera body. A memory 23 records information corresponding to a subject image photoelectrically converted by the solid-state imaging device 22. Reference numeral 24 denotes a finder for observing a subject image formed on the solid-state image sensor 22, which includes a liquid crystal display panel or the like.

  In this way, by applying the zoom lens of the present invention to an imaging apparatus such as a digital still camera, a compact imaging apparatus having high optical performance can be realized.

  In the following, Numerical Example 1 to Numerical Example 7 are shown.

  In the numerical examples, i indicates the order from the object side, ri is the i-th radius of curvature in order from the object side, di is the i-th lens thickness and air interval in order from the object side, and ni and νi are the object side, respectively. The refractive index and Abbe number at the d-line of the i-th material in order. BF is a back focus.

  Table 1 shows the relationship between the conditional expressions (1) to (5) and Examples 1 to 7, respectively.

  In Table 1, the lateral magnifications β2w and β2t at the wide-angle end and the telephoto end of the second lens unit L2 and the lateral magnifications β4w and β4t at the wide-angle end and the telephoto end of the fourth lens unit L4 are described for reference. ing.

  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 B to F and A ′ to F ′. Aspheric coefficient

It is expressed by the following formula.

  The aspheric shape is displayed by adding * to the surface number.

“E-x” means 10 ^−x .

(Numerical example 1)
Unit mm

Surface data surface number rd nd vd
1 46.387 0.91 1.84666 23.9
2 29.238 3.92 1.48749 70.2
3 -274.226 0.63
4 33.397 2.47 1.71300 53.9
5 107.612 (variable)
6 102.207 1.07 1.88300 40.8
7 5.722 2.80
8 -22.530 0.89 1.77250 49.6
9 17.499 0.08
10 10.741 2.69 1.92286 18.9
11 72.161 (variable)
12 * 15.035 0.99 1.58313 59.4
13 * -13.224 1.28
14 (Aperture) ∞ 2.03
15 71.351 1.49 1.92286 18.9
16 9.857 0.17
17 10.414 1.63 1.77250 49.6
18 -9.896 (variable)
19 * 32.734 1.04 1.69350 53.2
20 * 5.680 (variable)
21 -610.102 1.60 1.88300 40.8
22 -11.363 (variable)
23 ∞ 0.80 1.51633 64.1
24 ∞ (variable)

Aspheric data 12th surface
K = -1.53973e + 000 A 4 = -1.70567e-004 A 6 = 2.06757e-005 A 8 = -1.75786e-006 A10 = 8.45932e-009
Side 13
K = -3.81666e + 000 A 4 = 1.77528e-004 A 6 = 2.11832e-005 A 8 = -1.19231e-006 A10 = 1.78553e-008
19th page
K = 8.95045e-001 A 4 = -7.28776e-005 A 6 = 8.74312e-006 A 8 = -2.04432e-007 A10 = 3.51374e-009
20th page
K = 3.70279e-001 A 4 = 2.87976e-004 A 6 = -2.79339e-005 A 8 = 5.99582e-006 A10 = -3.97598e-007

Various data Zoom ratio 9.78

Focal length 4.34 13.47 42.42
F number 3.10 4.38 5.77
Angle of view 41.60 15.95 5.19
Image height 3.85 3.85 3.85
Total lens length 49.11 58.19 70.06
BF 5.20 3.94 3.15

d 5 0.46 12.62 24.10
d11 13.63 5.23 0.85
d18 1.53 2.77 3.01
d20 2.29 7.64 12.97
d22 4.08 2.82 2.03
d24 0.59 0.59 0.59

Zoom lens group data group Start surface Focal length
1 1 44.71
2 6 -6.65
3 12 8.22
4 19 -10.07
5 21 13.10

(Numerical example 2)
Unit mm

Surface data surface number rd nd vd
1 74.617 1.03 1.80610 33.3
2 37.299 5.56 1.49700 81.5
3 3046.357 0.19
4 39.377 3.98 1.60311 60.6
5 205.617 (variable)
6 45.387 0.99 1.88300 40.8
7 10.767 2.51
8 41.964 1.02 1.80 400 46.6
9 9.990 3.45
10 -21.358 1.02 1.74950 35.3
11 -105.249 0.19
12 22.078 1.98 1.92286 18.9
13 -695.286 (variable)
14 (Aperture) ∞ (Variable)
15 * 12.158 3.27 1.58313 59.4
16 -124.109 1.53
17 26.401 1.48 1.71999 50.2
18 14.051 1.80
19 20.381 1.91 2.00330 28.3
20 8.538 2.00 1.60311 60.6
21 -35.125 (variable)
22 36.376 2.31 1.80518 25.4
23 26.373 1.16 1.60311 60.6
24 14.969 (variable)
25 15.688 4.50 1.58313 59.4
26 -10.529 1.56 1.60342 38.0
27 -35.467 (variable)
28 ∞ 0.80 1.51633 64.1
29 ∞ (variable)

Aspheric data 15th surface
K = 1.91328e-001 A 4 = -8.66915e-005 A 6 = -5.46115e-007 A 8 = 2.82575e-008 A10 = -1.01872e-009

Various data Zoom ratio 19.40

Focal length 4.79 15.11 92.89
F number 2.87 3.87 5.60
Angle of view 38.80 14.29 2.37
Image height 3.85 3.85 3.85
Total lens length 91.81 100.17 123.52
BF 9.07 13.48 10.26

d 5 0.94 19.83 45.80
d13 25.04 9.01 0.90
d14 11.13 4.96 1.09
d21 0.90 3.90 14.10
d24 1.02 5.28 7.65
d27 7.00 11.41 8.19
d29 1.54 1.54 1.54

Zoom lens group data group Start surface Focal length
1 1 67.95
2 6 -9.82
3 15 19.83
4 22 -41.62
5 25 19.97

(Numerical Example 3)
Unit mm

Surface data surface number rd nd vd
1 77.859 1.90 1.80610 33.3
2 38.162 5.50 1.49700 81.5
3 5579.689 0.20
4 39.435 4.30 1.60311 60.6
5 193.345 (variable)
6 46.636 1.00 1.83481 42.7
7 10.369 2.70
8 24.826 0.85 1.77250 49.6
9 9.988 3.60
10 -22.515 0.80 1.83481 42.7
11 -340.954 0.12
12 21.755 2.25 1.92286 18.9
13 923.134 (variable)
14 (Aperture) ∞ (Variable)
15 * 11.916 3.45 1.58313 59.4
16 -84.373 2.80
17 42.190 1.15 1.60342 38.0
18 13.010 0.30
19 22.098 0.80 2.00330 28.3
20 8.458 2.15 1.71999 50.2
21 -44.763 (variable)
22 63.020 1.00 1.76182 26.5
23 58.335 0.60 1.60311 60.6
24 18.000 (variable)
25 20.910 4.00 1.77250 49.6
26 -10.871 0.60 1.80610 33.3
27 -48.531 (variable)
28 ∞ 0.80 1.51633 64.1
29 ∞ (variable)

Aspheric data 15th surface
K = 3.22611e-001 A 4 = -1.03271e-004 A 6 = -6.77678e-007 A 8 = 5.18752e-008 A10 = -2.45955e-009

Various data Zoom ratio 19.24

Focal length 5.15 20.27 99.10
F number 2.87 3.83 5.48
Angle of view 36.78 10.75 2.22
Image height 3.85 3.85 3.85
Total lens length 91.63 100.53 125.00
BF 10.49 18.16 10.34

d 5 0.90 24.02 47.08
d13 24.11 5.11 1.74
d14 10.39 3.54 1.01
d21 1.00 3.39 11.83
d24 4.40 5.98 12.66
d27 7.81 15.48 7.66
d29 2.15 2.15 2.15

Zoom lens group data group Start surface Focal length
1 1 69.78
2 6 -9.86
3 15 19.13
4 22 -42.07
5 25 20.35

(Numerical example 4)
Unit mm

Surface data surface number rd nd vd
1 70.878 1.30 1.80610 33.3
2 32.968 4.70 1.49700 81.5
3 -111.350 0.10
4 26.866 2.40 1.60311 60.6
5 54.549 (variable)
6 26.963 0.70 1.88300 40.8
7 6.026 2.60
8 -20.552 0.60 1.69680 55.5
9 23.424 0.40
10 12.212 1.70 1.92286 18.9
11 39.217 (variable)
12 (Aperture) ∞ 1.50
13 * 15.113 2.00 1.69350 53.2
14 * -110.436 3.00
15 45.026 0.60 1.84666 23.9
16 11.428 0.27
17 11.905 2.00 1.60311 60.6
18 -19.292 (variable)
19 25.973 1.20 1.76182 26.5
20 30.131 0.60 1.60311 60.6
21 9.597 (variable)
22 18.697 3.20 1.80 400 46.6
23 -13.236 0.60 1.80518 25.4
24 -61.067 (variable)
25 ∞ 0.50 1.51633 64.1
26 ∞ (variable)

Aspherical data 13th surface
K = -1.19364e + 000 A 4 = 2.35674e-005 A 6 = -7.55800e-007 A 8 = 8.65820e-008

14th page
K = -1.55414e + 003 A 4 = -3.64989e-005 A 6 = 3.74564e-006 A 8 = 2.59198e-008

Various data Zoom ratio 16.66

Focal length 6.00 24.02 99.98
F number 2.90 3.29 4.36
Angle of view 30.77 8.46 2.05
Statue height 3.57 3.57 3.57
Total lens length 69.78 84.83 100.78
BF 8.96 15.90 6.10

d 5 0.70 23.55 38.58
d11 19.83 3.89 1.47
d18 1.50 3.94 4.18
d21 9.15 7.92 20.80
d24 8.19 15.12 5.32
d26 0.45 0.45 0.45

Zoom lens group data group Start surface Focal length
1 1 55.06
2 6 -8.10
3 13 14.16
4 19 -27.14
5 22 18.21

(Numerical example 5)
Unit mm

Surface data surface number rd nd vd
1 43.599 1.27 1.84666 23.9
2 27.041 3.88 1.48749 70.2
3 237.616 0.24
4 30.838 2.85 1.70731 54.3
5 121.146 (variable)
6 62.960 0.97 1.86845 42.1
7 6.958 3.29
8 -29.264 0.85 1.81815 46.1
9 16.475 0.56
10 13.256 1.96 1.92286 18.9
11 73.933 (variable)
12 * 14.924 2.85 1.58313 59.4
13 * -19.197 2.39
14 (Aperture) ∞ 2.09
15 40.818 0.97 1.92271 18.9
16 10.738 0.27
17 13.526 2.19 1.78736 48.5
18 -16.033 (variable)
19 -172.133 0.85 1.57129 42.4
20 * 8.659 (variable)
21 156.632 2.18 1.78084 49.0
22 -13.062 (variable)
23 ∞ 0.80 1.49000 70.0
24 ∞ (variable)

Aspheric data 12th surface
K = -1.18045e + 000 A 4 = -1.07674e-004 A 6 = -9.59113e-007 A 8 = 3.58907e-009 A10 = -1.45640e-010

Side 13
K = -8.29356e + 000 A 4 = -8.00732e-005 A 6 = 2.80192e-007 A 8 = 7.05708e-009 A10 = -3.74408e-011

20th page
K = 7.25552e-001 A 4 = 1.34001e-004 A 6 = -7.43617e-006 A 8 = -1.34818e-008

Various data Zoom ratio 9.80

Focal length 5.38 19.88 52.69
F number 2.88 3.84 4.18
Angle of view 35.60 10.96 4.18
Image height 3.85 3.85 3.85
Total lens length 61.81 67.16 77.83
BF 7.16 6.02 4.88

d 5 0.76 15.08 27.65
d11 18.50 3.93 1.09
d18 1.74 7.10 5.74
d20 3.72 5.11 8.54
d22 3.30 2.16 1.02
d24 3.32 3.32 3.32

Zoom lens group data group Start surface Focal length
1 1 47.27
2 6 -7.59
3 12 11.20
4 19 -14.41
5 21 15.53

(Numerical example 6)
Unit mm

Surface data surface number rd nd vd
1 45.487 1.15 1.84666 23.9
2 27.522 3.65 1.48749 70.2
3 -182.544 0.20
4 32.533 2.03 1.71300 53.9
5 116.441 (variable)
6 253.910 1.00 1.88300 40.8
7 5.823 2.50
8 -21.927 0.80 1.77250 49.6
9 19.018 0.22
10 10.866 1.53 1.92286 18.9
11 62.902 (variable)
12 * 13.143 1.91 1.58313 59.4
13 * -12.880 1.58
14 (Aperture) ∞ 1.97
15 66.373 0.90 1.92286 18.9
16 9.666 0.10
17 11.022 1.67 1.77250 49.6
18 -10.269 (variable)
19 26.314 0.80 1.69350 53.2
20 * 5.731 (variable)
21 -157.045 1.80 1.83481 42.7
22 -12.096 (variable)
23 ∞ 0.80 1.51633 64.1
24 ∞ (variable)

Aspheric data 12th surface
K = -2.39987e + 000 A 4 = -1.26814e-004 A 6 = 2.25922e-005 A 8 = -1.47250e-006 A10 = -1.37571e-010

Side 13
K = -5.10620e + 000 A 4 = 7.59035e-005 A 6 = 2.25827e-005 A 8 = -9.87818e-007 A10 = -3.53221e-011

20th page
K = 2.67619e-001 A 4 = 8.01417e-005 A 6 = -8.57578e-006 A 8 = -9.35838e-007

Various data Zoom ratio 9.78

Focal length 5.15 15.41 50.36
F number 3.40 4.58 5.77
Angle of view 36.80 14.03 4.37
Image height 3.85 3.85 3.85
Total lens length 47.64 57.21 69.42
BF 5.89 4.94 4.12

d 5 0.68 12.96 24.60
d11 12.68 4.95 1.01
d18 1.22 2.54 2.10
d20 3.09 7.73 13.52
d22 5.00 4.05 3.24
d24 0.36 0.36 0.36

Zoom lens group data group Start surface Focal length
1 1 41.85
2 6 -6.64
3 12 8.39
4 19 -10.74
5 21 15.61

(Numerical example 7)
Unit mm

Surface data surface number rd nd vd
1 46.080 1.10 1.84666 23.9
2 29.191 3.86 1.48749 70.2
3 -254.439 0.87
4 32.994 2.08 1.71300 53.9
5 110.300 (variable)
6 171.921 1.32 1.88300 40.8
7 5.812 2.80
8 -23.390 0.98 1.77250 49.6
9 18.976 0.10
10 10.860 1.80 1.92286 18.9
11 64.617 (variable)
12 * 13.174 1.15 1.58313 59.4
13 * -12.917 1.10
14 (Aperture) ∞ 1.86
15 91.424 1.30 1.92286 18.9
16 9.763 0.27
17 10.387 1.62 1.77250 49.6
18 -9.915 (variable)
19 * 29.476 1.02 1.69350 53.2
20 * 5.641 (variable)
21 -93.283 2.45 1.88300 40.8
22 -11.593 (variable)
23 ∞ 0.80 1.51633 64.1
24 ∞ (variable)

Aspheric data 12th surface
K = -2.35386e + 000 A 4 = -1.40772e-004 A 6 = 1.49443e-005 A 8 = -3.24701e-006 A10 = 5.43511e-009

Side 13
K = -4.06692e + 000 A 4 = 1.41380e-004 A 6 = 2.53715e-005 A 8 = -3.49722e-006 A10 = 2.15072e-008

19th page
K = 8.85258e + 000 A 4 = -5.95611e-005 A 6 = -1.08213e-006 A 8 = 1.25880e-006 A10 = -1.95314e-008

20th page
K = 3.52436e-001 A 4 = 2.71289e-004 A 6 = -2.84270e-005 A 8 = 6.19290e-006 A10 = -3.77314e-007

Various data Zoom ratio 9.80

Focal length 4.81 4.97 47.14
F number 3.16 3.15 5.77
Angle of view 38.69 37.77 4.67
Image height 3.85 3.85 3.85
Total lens length 48.44 47.43 70.26
BF 5.30 5.42 3.19

d 5 0.66 0.66 24.42
d11 12.88 11.91 1.01
d18 1.34 1.50 1.98
d20 2.32 2.00 13.72
d22 4.00 4.11 1.89
d24 0.78 0.78 0.78

Zoom lens group data group Start surface Focal length
1 1 43.62
2 6 -6.80
3 12 7.99
4 19 -10.24
5 21 14.78

L1 1st lens group L2 2nd lens group L3 3rd lens group L4 4th lens group L5 5th lens group d d line g g line ΔM meridional image surface ΔS sagittal image surface SP aperture IP imaging surface G CCD force plate And glass blocks such as low-pass filters

Claims (5)

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 fourth lens having a negative refractive power And a fifth lens group having a positive refractive power. During zooming from the wide-angle end to the telephoto end, the distance between the first lens group and the second lens group increases, and the third lens group and the third lens group A zoom lens in which all the lens groups move so that the interval between the fifth lens groups is increased, wherein the focal length of the second lens group is f2, the focal length of the fourth lens group is f4, and the fifth lens. The focal length of the group is f5, the focal length of the entire system at the wide-angle end is fw, the focal length of the entire system at the telephoto end is ft, and the lateral magnifications of the fifth lens group at the wide-angle end and the telephoto end are β5w and β5t, respectively. When to do
0.01 ≦ (| f4 | / f5) /Z≦0.11
Z = ft / fw
0.01 ≦ | f2 | /ft≦0.2
0.1 ≦ (f5 / | f2 |) /Z≦0.25
0.01 ≦ (| β5t | / | β5w |) /Z≦0.14
A zoom lens characterized by satisfying the following conditions:   2. The zoom lens according to claim 1, wherein the image forming position is changed by moving all or part of the third lens group so as to have a component perpendicular to the optical axis.   The third lens group includes one or more positive lenses including a positive lens disposed closest to the object side and one or more negative lenses, and at least one of the positive lenses included in the third lens group. The zoom lens according to claim 1, wherein one is an aspheric lens.   4. The zoom lens according to claim 1, wherein focusing is performed by moving the fourth lens group or the fifth lens group in an optical axis direction. 5.   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.

Images