JP2017215410A - Zoom lens and imaging device having the same - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a zoom lens achieving a high magnification as well as reduction in size and weight, and high optical performance, and an imaging device having the zoom lens.SOLUTION: The zoom lens includes, successively from an object side to an image side, a first lens group L1 having a positive refractive power, a second lens group L2 having a negative refractive power, and a rear group including at least two lens groups, in which at a telephoto end, at least the second lens group L2 moves in such a manner that an interval between the first lens group L1 and the second lens group L2 increases compared to an arrangement at wide angle end. The first lens group L1 has at least one negative lens and three positive lenses; the second lens group L2 has at least one positive lens and at least one negative lens constituted by a material satisfying conditions of N2na>2.3-0.01×νd2na and 1.75<N2na<2.7, where N2na represents a refractive index of the material with respect to d-line and νd2na represents an Abbe number with respect to d-line.SELECTED DRAWING: Figure 1

Description

  The present invention relates to a zoom lens and an image pickup apparatus having the same, for example, a camera using a solid-state image pickup device such as a video camera, an electronic still camera, a broadcast camera, a surveillance camera, or a camera using a silver salt film. Is preferred.

  In recent years, imaging devices such as a video camera using a solid-state imaging device, a digital still camera, a broadcasting camera, a surveillance camera, and a camera using a silver salt film have been improved in function, and the entire device has been downsized. As a photographing optical system used therefor, there is a demand for a zoom lens having a short overall lens length, a compact size, a high zoom ratio, and a high resolution.

  As a zoom lens that meets these requirements, in order from the object side to the image side, a positive lead type composed of first and second lens groups having positive and negative refractive power and two or more subsequent groups including a group of positive refractive power. A zoom lens is known (Patent Document 1).

  In addition, in a positive lead type zoom lens, there is known a zoom lens in which the lens shape, the Abbe number of the material, the refractive index, and the like of the lens included in the second lens group that performs main zooming are appropriately defined (patent) Reference 2).

Japanese Patent No. 5028104 Japanese Patent No. 5127352

  In recent years, a zoom lens used in an image pickup apparatus is strongly demanded to have a high zoom ratio and a small lens system as a whole in response to downsizing of the image pickup apparatus. In general, in order to reduce the size of a zoom lens, the number of lenses may be reduced while increasing the refractive power of each lens group constituting the zoom lens.

  However, in such a zoom lens, the refractive power of each lens increases and the curvature of each surface increases, so that the lens thickness increases to ensure an appropriate edge thickness. As a result, the shortening effect of the lens system becomes insufficient, and variations in various aberrations increase, making it difficult to obtain high optical performance in the entire zoom range.

  In particular, in a positive lead type zoom lens, it is an important factor to appropriately set the lens configuration of the second lens group that performs main zooming. If the lens configuration of the second lens group is not appropriate, aberration fluctuations due to zooming, such as chromatic aberration, spherical aberration, halocoma aberration, and chromatic difference of spherical aberration, increase, and high performance can be achieved with a high zoom ratio. It becomes difficult.

  In addition, when a high zoom ratio is achieved, axial chromatic aberration increases at the telephoto end, and residual aberrations of the secondary spectrum increase, making it difficult to correct these satisfactorily.

  For example, in a zoom lens for a surveillance camera that requires a high zoom ratio, the lens configuration of the first lens group and the lens configuration of the second lens group are appropriately set to suppress the secondary spectrum of axial chromatic aberration on the telephoto side. It becomes important to do.

  An object of the present invention is to provide a zoom lens that has a high zoom ratio, corrects chromatic aberration well over the entire zoom range from the wide-angle end to the telephoto end, and has high optical performance in the entire zoom range, and an imaging apparatus having the same. To do.

In order to achieve the above object, a zoom lens according to the present invention provides:
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 rear group including two or more lens groups, and at the telephoto end compared to the wide-angle end A zoom lens in which at least the second lens group moves so that the distance between the first lens group and the second lens group is wide, and the first lens group includes at least one negative lens and three positive lenses. The second lens group has at least one positive lens, and the refractive index of the material for the d-line is N2na, and the Abbe number for the d-line is νd2na,
N2na> 2.3-0.01 · νd2na
1.75 <N2na <2.7
And at least one negative lens L2na made of a material that satisfies the following conditions.

  According to the present invention, it is possible to obtain a zoom lens having a good optical performance over the entire zoom range from the wide-angle end to the telephoto end while reducing the overall length of the lens.

FIG. 3 is a lens cross-sectional view at the wide angle end of the zoom lens according to the first exemplary embodiment. FIG. 4 is an aberration diagram at Example 1 at the wide-angle end. FIG. 6 is an aberration diagram for Example 1 at a focal length of 38.0 mm. FIG. 6 is an aberration diagram at Example 1 at a telephoto end. 6 is a lens cross-sectional view at a wide angle end of a zoom lens according to Embodiment 2. FIG. FIG. 4 is an aberration diagram at Example 2 at the wide-angle end. FIG. 6 is an aberration diagram for Example 2 at a focal length of 38.6 mm. FIG. 6 is an aberration diagram at Example 2 at a telephoto end. 6 is a lens cross-sectional view at a wide angle end of a zoom lens according to Embodiment 3; FIG. FIG. 6 is an aberration diagram at Example 3 at the wide-angle end. FIG. 6 is an aberration diagram for Example 3 at a focal length of 40.4 mm. FIG. 6 is an aberration diagram for Example 3 at the telephoto end. 6 is a lens cross-sectional view at a wide angle end of a zoom lens according to Embodiment 4; FIG. FIG. 6 is an aberration diagram at Example 4 at the wide-angle end. FIG. 6 is an aberration diagram for Example 4 at a focal length of 40.5 mm. FIG. 6 is an aberration diagram at Example 4 for the telephoto end. 6 is a lens cross-sectional view at the wide-angle end of a zoom lens according to Example 5. FIG. FIG. 10 is an aberration diagram at Example 5 at the wide-angle end. FIG. 10 is an aberration diagram for Example 5 at a focal length of 39.1 mm. FIG. 10 shows aberration diagrams at the telephoto end of Example 5. 10 is a lens cross-sectional view at a wide angle end of a zoom lens according to Example 6. FIG. FIG. 10 is an aberration diagram at Example 6 at the wide-angle end. FIG. 12 is an aberration diagram for Example 6 at a focal length of 35.3 mm. FIG. 10 is an aberration diagram at Example 10 at the telephoto end. 10 is a lens cross-sectional view at the wide-angle end of a zoom lens according to Example 7. FIG. FIG. 10 is an aberration diagram at Example 7 at the wide-angle end. FIG. 10 is an aberration diagram for Example 7 at a focal length of 25.9 mm. FIG. 10 shows aberration diagrams at the telephoto end of Example 7. It is the schematic of a partial dispersion ratio characteristic figure. It is a principal part schematic of the imaging device of this invention.

  Embodiments of the present invention will be described below in detail with reference to the accompanying drawings.

  FIG. 1 is a lens cross-sectional view when focusing on an object at infinity at the wide-angle end of Numerical Embodiment 1 as Embodiment 1 of the present invention. 2A, 2 </ b> B, and 2 </ b> C are longitudinal directions when focusing on an object at infinity at the wide-angle end, f = 38.0 mm, and the telephoto end (long focal length end) in Numerical Example 1. FIG. It is an aberration diagram.

  FIG. 3 is a lens cross-sectional view when focusing on an object at infinity at the wide-angle end of Numerical Example 2 as Embodiment 2 of the present invention. 4A, 4 </ b> B, and 4 </ b> C are longitudinal directions when focusing on an object at infinity at the wide-angle end, f = 38.6 mm, and the telephoto end (long focal length end) in Numerical Example 2. FIG. It is an aberration diagram.

  FIG. 5 is a lens cross-sectional view when focusing on an object at infinity at the wide-angle end of Numerical Embodiment 3 as Embodiment 3 of the present invention. 6A, 6B, and 6C show the vertical direction when focusing on an object at infinity at the wide-angle end, f = 40.4 mm, and the telephoto end (long focal length end) in Numerical Example 3. FIG. It is an aberration diagram.

  FIG. 7 is a lens cross-sectional view when focusing on an object at infinity at the wide angle end according to Numerical Example 4 as Embodiment 4 of the present invention. 8A, 8B, and 8C show the vertical direction when focusing on an infinite object at the wide-angle end, f = 40.5 mm, and the telephoto end (long focal length end) in Numerical Example 4. FIG. It is an aberration diagram.

  FIG. 9 is a lens cross-sectional view when focusing on an object at infinity at the wide angle end according to Numerical Example 5 as Example 5 of the present invention. FIGS. 10A, 10B, and 10C are vertical directions when focusing on an object at infinity at the wide-angle end, f = 39.1 mm, and the telephoto end (long focal length end) in Numerical Example 5. FIG. It is an aberration diagram.

  FIG. 11 is a lens cross-sectional view when focusing on an object at infinity at the wide angle end according to Numerical Example 6 as Example 6 of the present invention. FIGS. 12A, 12B, and 12C are longitudinal views when focusing on an object at infinity at the wide-angle end, f = 35.3 mm, and the telephoto end (long focal length end) in Numerical Example 6. FIG. It is an aberration diagram.

  FIG. 13 is a lens cross-sectional view when focusing on an object at infinity at the wide angle end according to Numerical Example 7 as Example 7 of the present invention. FIGS. 14A, 14B, and 14C are longitudinal views when focusing on an object at infinity at the wide-angle end, f = 25.9 mm, and the telephoto end (long focal length end) in Numerical Example 7. It is an aberration diagram.

  In the longitudinal aberration diagram, spherical aberration and lateral chromatic aberration indicate d-line (solid line), g-line (two-dot chain line), and C-line (one-dot chain line). Astigmatism indicates the d-line meridional image plane (broken line) and the sagittal image plane (solid line). Fno represents an F number, and ω represents a shooting half angle of view. In the longitudinal aberration diagram, the spherical aberration is drawn on a scale of 0.2 mm, the astigmatism is 0.2 mm, the distortion is 10%, and the lateral chromatic aberration is drawn on a scale of 0.1 mm.

  The zoom lens according to each embodiment 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, and a rear group including two or more lens groups. Yes. In this zoom lens, at least the second lens unit moves so that the distance between the first lens unit and the second lens unit at the telephoto end is wider than at the wide-angle end. The rear group has at least one lens unit having a positive refractive power. For example, the rear group includes a third lens group having a positive refractive power and a fourth lens group having a positive refractive power in order from the object side to the image side.

  In addition, the first lens group of each embodiment has at least one negative lens and three positive lenses. Accordingly, the refractive power of each positive lens in the first lens group having a positive refractive power can be made relatively small, so that a glass material having a low refractive index and low dispersion can be used. This makes it possible to reduce the secondary spectrum of axial chromatic aberration that occurs because the axial ray passes through a high position, particularly at the telephoto end.

  The second lens group of each embodiment has at least one negative lens and one positive lens. As a result, achromaticity in the second lens group can be achieved, and zoom variation of chromatic aberration can be suppressed.

  In each embodiment, it is more preferable to satisfy one or more of the following conditions. According to this, an effect corresponding to each condition can be obtained.

  The focal length of at least one negative lens L2na in the second lens unit L2 is f2na, the refractive index of the material with respect to the d-line (wavelength 587.6 nm) is N2na, the Abbe number with respect to the d-line is νd2na, and the partial dispersion ratio is θgFna. .

  The focal lengths of the first lens unit L1 and the second lens unit L2 are f1 and f2, respectively.

  Let fw be the focal length of the entire system at the wide-angle end.

  The Abbe number of the material of at least one positive lens L2np in the second lens unit L2 is νd2pa and the partial dispersion ratio is θgFpa.

At this time, each example is
2.3-0.01 × νd2na <N2na (1)
1.75 <N2na <2.7 (2)
0.5 <f2na / f2 <2.5 (3)
−10.0 <f1 / f2 <−5.3 (4)
−1.8 <f2 / fw <−0.5 (5)
5.0 <f1 / fw <22.0 (6)
(Θgfpa−θgfna) / (νd2pa−νd2na) <− 5.0 × 10−3 (7)
The following conditional expression is satisfied.

Here, the partial dispersion ratio and the Abbe number of the material of the optical element (lens) used in this example are as follows. The refractive indexes of the Fraunhofer line for g-line (435.8 nm), F-line (486.1 nm), d-line (587.6 nm), and C-line (656.3 nm) are Ng, NF, Nd, and NC, respectively. To do. The partial dispersion ratio θgF for the Abbe number νd, g-line and F-line is as follows.
νd = (Nd−1) / (NF−NC)
θgF = (Ng−NF) / (NF−NC)
Next, the technical meaning of each conditional expression described above will be described.

  Conditional expressions (1) and (2) are expressions defining the relationship between the refractive index and the Abbe number of the material of the negative lens L2na in the second lens unit L2. When the refractive index exceeds the lower limit value of the conditional expression (1) calculated from the Abbe number value, dispersion with respect to the refractive index becomes too large. As a result, the difference in dispersion from the positive lens in the second lens unit L2 is reduced, so that the secondary achromatization increases the refractive power of L2na, and the curvature increases, resulting in higher-order aberrations. Since it occurs, it is not preferable.

   When the refractive index exceeds the lower limit value of conditional expression (2), the refractive power of L2na becomes relatively small when the curvature of L2na is the same. As a result, the refractive power of the second lens unit L2 becomes small, and in order to ensure a high zoom ratio, the amount of movement of L2 becomes too large, which is disadvantageous for downsizing the entire system. Further, if the curvature of L2na is increased in order to increase the refractive power, it is disadvantageous for high-order aberrations and disadvantageous for high performance in the entire zoom range.

  If the refractive index exceeds the upper limit value, the effect of correcting the Petzval sum to the negative side by the negative lens L2na is diminished. As a result, the curvature of field greatly falls to the under side, which is not good.

  Conditional expression (3) is an expression that prescribes the sharing of the refractive power of the negative lens L2na in the second lens unit L2. When the lower limit value of conditional expression (3) is exceeded, the focal length f2na of the negative lens L2na decreases, and the aberration generated by off-axis rays at the wide angle end of the negative lens L2na increases. As a result, lateral chromatic aberration increases at the wide-angle end, and a larger barrel distortion occurs. On the other hand, when the upper limit is exceeded, the focal length f2na of the negative lens L2na becomes large, and it is necessary to share a large refractive power with the other negative lens of the second lens unit L2. As a result, the number of lenses in the entire second lens unit L2 increases and the entire lens system increases in size.

  Conditional expressions (4), (5), and (6) are expressions that respectively define the share of the focal length of the first lens unit L1 and the second lens unit and the focal length at the wide angle end of the entire system.

  When the lower limit of conditional expression (4) is exceeded, the refractive power of the second lens unit L2 becomes too large, and various aberration variations due to zooming increase, making it difficult to obtain high optical performance in the entire zoom range. . On the other hand, if the upper limit is exceeded, the refractive power of the first lens unit L1 becomes too large, or the refractive power of the second lens unit L2 becomes too small, and it becomes difficult to obtain a high zoom ratio.

  When the lower limit of conditional expression (5) is exceeded, the refractive power of the second lens unit L2 becomes too large, and various aberration variations due to zooming increase, making it difficult to obtain high optical performance in the entire zoom range. . On the other hand, if the upper limit value is exceeded, the refractive power of the second lens unit L2 becomes too small. Therefore, in order to obtain a high zoom ratio, the amount of movement of the second lens unit L2 must be increased, and downsizing is difficult. Become.

  When the lower limit of conditional expression (6) is exceeded, the refractive power of the first lens unit L1 becomes too large, and it becomes difficult to obtain a high zoom ratio. On the other hand, if the value exceeds the upper limit, the refractive power of the first lens unit L1 becomes too small, and it becomes difficult to suppress fluctuations in various aberrations, which is not preferable for obtaining high optical performance over the entire zoom range.

  In each embodiment, the lens configuration of the second lens group is specified as described above, and achromaticity is effectively performed so as to satisfy the conditional expression (7). In each embodiment, the entire system is made compact while suppressing the secondary spectrum of axial chromatic aberration on the telephoto side, which increases as the zoom lens increases in magnification (higher zoom ratio).

  If the upper limit of conditional expression (7) is exceeded, it will be difficult to perform sufficient achromatization with the second lens group. In particular, it is difficult to satisfactorily correct the secondary spectrum of axial chromatic aberration on the telephoto side. Achromaticity here refers to the degree of correction of the secondary spectrum of axial chromatic aberration in each embodiment.

  Further, the strong achromaticity in the second lens unit L2 means that the inclination of the achromatic lens in the partial dispersion characteristic diagram in which the vertical axis in FIG. 15 indicates the partial dispersion ratio and the horizontal axis indicates the Abbe number indicates the two-dot chain line C2. It means that it is steep.

  Originally, if a glass material that has a flat inclination as shown by the solid line AC in FIG. 15 is selected, three-color achromaticity is achieved, and the occurrence of chromatic aberration can be suppressed.

  However, if the first lens unit having a positive refractive power is configured by selecting an actual glass material, it often has a certain degree of inclination as indicated by a one-dot chain line C1. Since the secondary spectrum of axial chromatic aberration is generated in proportion to this inclination multiplied by the focal length, the larger the inclination, the larger the secondary spectrum remains.

  In order to correct chromatic aberration that cannot be corrected by the first lens group in this way, the second lens group L2 is intentionally steeply inclined as shown by a two-dot chain line C2 in FIG. Need to build. Conditional expression (7) defines this inclination. As the value in conditional expression (7) becomes smaller, the achromatic gradient of the second lens group becomes steeper and the achromatic effect becomes larger. If the conditional expression (7) is not satisfied, the achromatic effect is reduced.

More preferably, the numerical ranges of the conditional expressions (2) to (7) are set as follows.
2.0 <N2na <2.2 (2a)
0.9 <f2na / f2 <1.5 (3a)
−8.0 <f1 / f2 <−5.5 (4a)
-1.7 <f2 / fw <-1.1 (5a)
7.0 <f1 / fw <15.0 (6a)
(Θgfpa−θgfna) / (νd2pa−νd2na) <− 5.3 × 10−3 (7a)
The features of the lens configurations of Numerical Examples 1 to 7 of the zoom lens of the present invention will be described below. In the lens cross-sectional views of each example, IP is an image plane, which corresponds to the imaging plane of the solid-state imaging device. In the following description, it is assumed that the lens configuration is arranged in order from the object side to the image side unless otherwise specified.

[Example 1]
In the zoom lens shown in the first embodiment, the first lens unit L1 having a positive refractive power, the second lens unit L2 having a negative refractive power, the third lens unit L3 having a positive refractive power, and the first lens unit L3 having a positive refractive power. It is composed of four lens units L4. During zooming from the wide-angle end to the telephoto end, the second lens unit L2 moves toward the image side to perform main magnification, and the fourth lens unit L4 moves along a convex locus toward the object side to mainly change magnification. It corrects image plane fluctuations associated with.

  The first lens unit L1 includes, in order from the object side, a negative lens, a cemented lens of one positive lens, and two positive lenses. By configuring the first lens group with four lens elements, chromatic aberration correction of spherical aberration, axial chromatic aberration, and lateral chromatic aberration is performed with a high zoom ratio.

  The second lens unit L2 includes, in order from the object side, one negative lens, a cemented lens composed of one negative lens and one positive lens, and a cemented lens composed of one positive lens and one negative lens. The most negative lens on the object side is the above-mentioned L2na, which has a characteristic of relatively low dispersion and low partial dispersion ratio while having a high refractive index. In addition, the positive lens that is the third lens from the object side is the above-mentioned L2pa, which has the characteristics of high dispersion and high partial dispersion ratio, and in combination with L2na, improves the correction of axial chromatic aberration at the telephoto end. Yes.

  The third lens unit L3 includes two positive lenses and one negative lens in order from the object side. The lens on the most object side is a double-sided aspheric lens and corrects spherical aberration well.

  The fourth lens unit L4 includes a cemented lens including one positive lens and one negative lens. The object side surface of the positive lens is an aspherical surface, and the fluctuation of the curvature of field due to spherical aberration and zoom is corrected well. In addition, by using a cemented lens, fluctuations in axial chromatic aberration and lateral chromatic aberration due to zooming are well corrected.

  Table 1 shows values corresponding to the conditional expressions of the first embodiment. Numerical Example 1 satisfies all the conditional expressions, and realizes a zoom lens having good optical performance while achieving a high zoom ratio and miniaturization.

  The cemented lens in the present invention may exist as a separation lens having a minute air interval. This is within the assumption of deformation and change as the lens shape in the present invention, and the same applies to all the following embodiments.

[Example 2]
In the zoom lens shown in the second embodiment, the first lens unit L1 having a positive refractive power, the second lens unit L2 having a negative refractive power, the third lens unit L3 having a positive refractive power, and the first lens unit L3 having a positive refractive power. The lens unit includes a four lens unit L4 and a fifth lens L5 having a negative refractive power. During zooming from the wide-angle end to the telephoto end, the second lens unit L2 moves toward the image side to perform main magnification, and the fourth lens unit L4 moves along a convex locus toward the object side to mainly change magnification. It corrects image plane fluctuations associated with.

  The first lens unit L1 has the same configuration as that of the first embodiment.

  The second lens unit L2 includes two negative lenses, one positive lens, and a cemented lens of one negative lens in order from the object side. The most negative lens on the object side is the above-mentioned L2na, which has a characteristic of relatively low dispersion and low partial dispersion ratio while having a high refractive index. In addition, the positive lens that is the third lens from the object side is the above-mentioned L2pa, which has the characteristics of high dispersion and high partial dispersion ratio, and in combination with L2na, improves the correction of axial chromatic aberration at the telephoto end. Yes.

  The third lens unit L3 includes one positive lens and one negative lens in order from the object side. The positive lens is a double-sided aspheric lens and corrects spherical aberration well.

  The fourth lens unit L4 has the same configuration as that of the first embodiment.

  The fifth lens unit L5 includes one negative lens, one positive lens, and a cemented lens of one negative lens in order from the object side. By disposing the fifth lens unit L5 having negative refractive power between the fourth lens unit L4 that performs image surface correction and the image surface, the amount of movement of the fourth lens unit L4 for correcting the image surface can be reduced. It is possible to reduce this, and it is possible to suppress fluctuations in optical performance due to zooming.

  Table 1 shows values corresponding to the conditional expressions of the second embodiment. Numerical Example 2 satisfies all the conditional expressions, and realizes a zoom lens having good optical performance while achieving high zoom ratio and miniaturization.

[Example 3]
The arrangement of refractive power in the zoom lens shown in the third embodiment is the same as that in the first embodiment.

  The first lens unit L1 has the same configuration as that of the first embodiment.

  The second lens unit L2 has the same configuration as that of the second embodiment, and includes two negative lenses, one positive lens, and one cemented lens in order from the object side. The most negative lens on the object side is the above-mentioned L2na, which has a characteristic of relatively low dispersion and low partial dispersion ratio while having a high refractive index. The positive lens, which is the third lens from the object side, is the above-mentioned L2pa, has a feature of higher dispersion and higher partial dispersion ratio than the positive lens of Example 2, and is a telephoto end shaft in combination with L2na. The correction of upper chromatic aberration is made better.

  The third lens unit L3 has the same configuration as that of the second embodiment.

  The fourth lens unit L4 includes one positive lens and a cemented lens including one positive lens and one negative lens. The object side surface of the second positive lens from the object side is an aspherical surface, and the fluctuation of curvature of field due to spherical aberration and zoom is corrected well. In addition, by having a cemented lens, fluctuations in axial chromatic aberration and lateral chromatic aberration due to zooming are corrected well.

  Table 1 shows values corresponding to the conditional expressions of the third example. Numerical Example 3 satisfies all the conditional expressions, and realizes a zoom lens having good optical performance while achieving a high zoom ratio and miniaturization.

[Example 4]
The arrangement of refractive power in the zoom lens shown in the fourth embodiment is the same as that in the third embodiment.

  The first lens unit L1 has the same configuration as that of the third embodiment.

  The second lens unit L2 has the same configuration as that of the third embodiment, and includes two negative lenses, one positive lens, and one cemented lens in order from the object side. The most object side negative lens is the aforementioned L2na, which has the characteristics of low dispersion and low partial dispersion ratio while having a higher refractive index than the negative lens of Example 3. In addition, the positive lens that is the third lens from the object side is the above-mentioned L2pa, which has the characteristics of high dispersion and high partial dispersion ratio, and in combination with L2na, improves the correction of axial chromatic aberration at the telephoto end. Yes.

  The third lens unit L3 has the same configuration as that of the third embodiment.

  The fourth lens unit L4 has the same configuration as that of the third embodiment.

  Table 1 shows values corresponding to the conditional expressions of the fourth example. Numerical Example 4 satisfies all the conditional expressions, and realizes a zoom lens having good optical performance while achieving a high zoom ratio and miniaturization.

[Example 5]
The arrangement of refractive power in the zoom lens shown in the fifth embodiment is the same as that in the second embodiment.

  The first lens unit L1 has the same configuration as that of the second embodiment.

  The second lens unit L2 has the same configuration as that of the second embodiment, and includes two negative lenses, one positive lens, and one cemented lens in order from the object side. The most object side lens is the aforementioned L2na, which has the characteristics of low dispersion and low partial dispersion ratio while having a higher refractive index than the negative lens of Example 2. In addition, the positive lens that is the third lens from the object side is the above-mentioned L2pa, which has the characteristics of high dispersion and high partial dispersion ratio, and in combination with L2na, improves the correction of axial chromatic aberration at the telephoto end. Yes.

  The third lens unit L3 has the same configuration as that of the second embodiment.

  The fourth lens unit L4 has the same configuration as that of the second embodiment.

Table 1 shows values corresponding to the conditional expressions of the fifth example. Numerical Example 5 satisfies all the conditional expressions, and realizes a zoom lens having good optical performance while achieving high zoom ratio and miniaturization.
[Example 6]
The arrangement of refractive power in the zoom lens shown in the sixth embodiment is the same as that in the second embodiment.

  The first lens unit L1 has the same configuration as that of the second embodiment.

  The second lens unit L2 has the same configuration as that of the second embodiment, and includes two negative lenses, one positive lens, and one cemented lens in order from the object side. The lens on the most object side is the above-mentioned L2na, and has a characteristic of relatively low dispersion and low partial dispersion ratio while having a high refractive index. In addition, the positive lens that is the third lens from the object side is the above-mentioned L2pa, which has the characteristics of high dispersion and high partial dispersion ratio, and in combination with L2na, improves the correction of axial chromatic aberration at the telephoto end. Yes.

  The third lens unit L3 has the same configuration as that of the second embodiment.

  The fourth lens unit L4 has the same configuration as that of the second embodiment.

  Table 1 shows values corresponding to the conditional expressions of the sixth example. Numerical Example 6 satisfies all of the conditional expressions, and realizes a zoom lens having good optical performance while achieving a high zoom ratio and miniaturization.

[Example 7]
The arrangement of refractive power in the zoom lens shown in the seventh embodiment is the same as that in the third embodiment.

  The first lens unit L1 has the same configuration as that of the third embodiment.

  The second lens unit L2 has the same configuration as that of the third embodiment, and includes two negative lenses, one positive lens, and one cemented lens in order from the object side. The most object side negative lens is the aforementioned L2na, which has the characteristics of low dispersion and low partial dispersion ratio while having a higher refractive index than the negative lens of Example 3. In addition, the positive lens that is the third lens from the object side is the above-mentioned L2pa, which has the characteristics of high dispersion and high partial dispersion ratio, and in combination with L2na, improves the correction of axial chromatic aberration at the telephoto end. Yes.

  The third lens unit L3 has the same configuration as that of the third embodiment.

  The fourth lens unit L4 has the same configuration as that of the third embodiment.

  Table 1 shows values corresponding to the conditional expressions of the seventh example. Numerical Example 7 satisfies all the conditional expressions, and realizes a zoom lens having good optical performance while achieving high zoom ratio and miniaturization.

  In each embodiment, high-power zoom that is compatible with high-magnification, compact, high-pixel digital cameras, video cameras, etc. with excellent correction of spherical aberration, coma, curvature of field, axial chromatic aberration, and lateral chromatic aberration. Has achieved the lens.

  Next, an embodiment of a video 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. 16, reference numeral 10 denotes a video camera body, and 11 denotes a photographing optical system constituted by any of the zoom lenses described in the first to seventh embodiments.

Reference numeral 12 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 11 and is built in the camera body.
Reference numeral 13 denotes a memory for recording information corresponding to the subject image photoelectrically converted by the solid-state imaging device 12.

  Reference numeral 14 denotes a finder for observing a 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 12 is displayed.

  As mentioned above, although preferable embodiment of this invention was described, this invention is not limited to these embodiment, A various deformation | transformation and change are possible within the range of the summary.

  Next, numerical examples 1 to 7 corresponding to the first to seventh embodiments of the present invention will be described.

  In each numerical example, i indicates the order of the surfaces from the object side, ri is the radius of curvature of the i-th surface from the object side, di is the i + 1-th distance from the i-side from the object side, ndi, νdi, θgFi is the refractive index, Abbe number, and partial dispersion ratio of the i-th optical member. The focal length of each surface represents the focal length of a single lens. The effective diameter of each surface represents the diameter through which the light beam passes.

  The focal length, F number, and half angle of view represent values when focusing on an object at infinity. BF is the distance from the final surface of the lens to the image plane.

  The aspherical shape is expressed by the following equation, where x is the coordinate in the optical axis direction, y is the coordinate in the direction perpendicular to the optical axis, R is the reference radius of curvature, k is the conic constant, and An is the nth-order aspherical coefficient. It is represented by However, “e−x” means “× 10−x”. A lens surface having an aspherical surface is marked with * on the left side of the surface number in each table.

x = (y ² / r) / {1+ (1-k · y ² / r ² ) ^0.5 } + A4 · y ⁴ + A6 · y ⁶ + A8 · y ⁸ + A10 · y ¹⁰


Numerical example 1
Unit mm

Surface number ri di ndi vdi θgFi Effective diameter Focal length
1 52.36274 1.25000 2.000690 25.46 0.6133 39.997 -99.842
2 34.05201 6.17530 1.496999 81.54 0.5374 37.519 76.486
3 299.53078 0.15000 1.000000 0.00 0.0000 36.755 0.000
4 39.01316 4.10218 1.496999 81.54 0.5374 33.501 93.754
5 227.92875 0.10000 1.000000 0.00 0.0000 32.665 0.000
6 25.33812 3.57663 1.595220 67.74 0.5442 27.775 67.839
7 64.05420 (variable) 1.000000 0.00 0.0000 26.716 0.000

8 54.92407 0.45000 2.049760 27.07 0.6050 11.364 -6.383
9 5.99299 2.67971 1.000000 0.00 0.0000 8.813 0.000
10 -24.73485 0.40000 2.049760 27.07 0.6050 8.663 -7.164
11 11.03373 1.05174 1.959060 17.47 0.6599 8.650 18.080
12 28.26208 0.26613 1.000000 0.00 0.0000 8.665 0.000
13 13.78882 2.78129 1.922860 18.90 0.6495 8.914 7.201
14 -11.85661 0.34000 1.953750 32.32 0.5898 8.738 -11.876
15 306.67147 (variable) 1.000000 0.00 0.0000 8.578 0.000

16 0.00000 1.00000 1.000000 0.00 0.0000 10.813 0.000
* 17 10.53083 3.31796 1.583126 59.38 0.5423 11.550 17.041
* 18 -167.65573 0.88698 1.000000 0.00 0.0000 11.169 0.000
19 -87.05370 1.36871 1.496999 81.54 0.5374 10.869 100.982
20 -32.06059 0.10000 1.000000 0.00 0.0000 10.638 0.000
21 17.38251 0.50000 2.001000 29.13 0.5997 9.991 -23.237
22 9.83826 (variable) 1.000000 0.00 0.0000 9.452 0.000

* 23 15.23310 3.47471 1.553320 71.68 0.5402 10.761 13.668
24 -13.88794 0.45000 1.959060 17.47 0.6599 10.683 -52.208
25 -19.42702 (variable) 1.000000 0.00 0.0000 10.783 0.000

26 0.00000 1.43000 1.516330 64.14 0.5352 20.000 0.000
27 0.00000 3.81000 1.000000 0.00 0.0000 20.000 0.000

Aspheric data 17th surface
K = 1.87640e-001 A 4 = -1.24609e-004 A 6 = -2.10089e-008 A 8 = -2.27820e-008 A10 = -2.78349e-012

18th page
K = 2.22806e + 001 A 4 = 3.50472e-005 A 6 = 6.95377e-007 A 8 = -3.09162e-008 A10 = 2.34640e-010

23rd page
K = -2.62894e-001 A 4 = -4.20230e-005 A 6 = -3.07583e-007 A 8 = 2.27478e-009

Various data Zoom ratio 33.00
Wide angle Medium Telephoto focal length 4.40 37.99 145.28
F number 1.90 2.60 4.90
Half angle of view 34.27 4.52 1.18
Image height 3.00 3.00 3.00
Total lens length 89.78 89.78 89.78
BF 3.81 3.81 3.81

d 7 0.60 20.08 24.94
d15 26.14 6.67 1.80
d22 13.30 5.68 21.32
d25 10.07 17.69 2.06
d27 3.81 3.81 3.81

Zoom lens group data group Start surface Focal length
1 1 36.92
2 8 -5.52
3 16 29.10
4 23 18.27
5 26 ∞


Numerical example 2
Unit mm


Surface number ri di ndi vdi θgFi Effective diameter Focal length
1 63.45522 1.25000 1.846660 23.78 0.6205 37.430 -114.533
2 38.15562 5.11497 1.496999 81.54 0.5374 35.461 81.580
3 591.01735 0.15000 1.000000 0.00 0.0000 34.845 0.000
4 42.72761 3.22694 1.537750 74.70 0.5393 32.195 104.362
5 172.54824 0.10000 1.000000 0.00 0.0000 31.536 0.000
6 28.65907 3.06660 1.595220 67.74 0.5442 27.994 77.200
7 72.68730 (variable) 1.000000 0.00 0.0000 27.224 0.000

8 109.54199 0.45000 2.049760 27.07 0.6050 11.149 -6.332
9 6.30521 2.67159 1.000000 0.00 0.0000 8.896 0.000
10 -20.73296 0.40000 2.001000 29.13 0.5997 8.800 -14.751
11 53.29359 0.12000 1.000000 0.00 0.0000 8.895 0.000
12 12.98841 2.97257 1.959060 17.47 0.6599 9.169 6.458
13 -10.77616 0.40000 2.001000 29.13 0.5997 8.939 -8.633
14 46.32169 (variable) 1.000000 0.00 0.0000 8.663 0.000

15 0.00000 1.00000 1.000000 0.00 0.0000 14.140 0.000
* 16 11.59572 4.79325 1.583126 59.38 0.5423 15.380 14.523
* 17 -27.01027 0.37924 1.000000 0.00 0.0000 15.017 0.000
18 22.25098 0.55000 2.000690 25.46 0.6133 13.407 -28.283
19 12.35245 (variable) 1.000000 0.00 0.0000 12.585 0.000

* 20 12.61009 3.17996 1.553320 71.68 0.5402 10.889 12.344
21 -13.65801 0.50000 1.959060 17.47 0.6599 10.491 -57.479
22 -18.40403 (variable) 1.000000 0.00 0.0000 10.507 0.000

23 42.00644 0.40000 1.772499 49.60 0.5521 7.323 -10.254
24 6.66370 0.95926 1.000000 0.00 0.0000 6.851 0.000
25 31.13861 2.34913 1.595509 39.24 0.5804 6.892 8.341
26 -5.78382 0.50000 1.883000 40.80 0.5652 6.935 -15.943
27 -10.17543 (variable) 1.000000 0.00 0.0000 7.190 0.000

28 0.00000 1.43000 1.516330 64.14 0.5352 20.000 0.000
29 0.00000 3.81000 1.000000 0.00 0.0000 20.000 0.000


Aspheric data 16th surface
K = -9.94741e-001 A 4 = -3.06997e-005 A 6 = 2.21579e-007

17th page
K = 0.00000e + 000 A 4 = 4.04667e-005 A 6 = 2.61400e-007 A 8 = -1.42630e-009

20th page
K = -1.29861e + 000 A 4 = -3.72561e-005 A 6 = -1.18188e-007

Various data Zoom ratio 34.00
Wide angle Medium telephoto focal length 4.22 38.58 143.35
F number 1.60 2.80 4.90
Half angle of view 35.43 4.45 1.20
Image height 3.00 3.00 3.00
Total lens length 85.19 85.19 85.19
BF 3.81 3.81 3.81

d 7 0.60 22.79 28.34
d14 29.54 7.35 1.80
d19 9.71 4.01 12.28
d22 4.57 10.26 2.00
d27 1.00 1.00 1.00
d29 3.81 3.81 3.81

Zoom lens group data group Start surface Focal length
1 1 39.74
2 8 -5.36
3 15 24.20
4 20 15.61
5 23 -35.00
6 28 ∞


Numerical Example 3
Unit mm


Surface number ri di ndi vdi θgFi Effective diameter Focal length
1 63.45522 1.25000 1.846660 23.78 0.6205 37.430 -114.533
2 38.15562 5.11497 1.496999 81.54 0.5374 35.461 81.580
3 591.01735 0.15000 1.000000 0.00 0.0000 34.845 0.000
4 42.72761 3.22694 1.537750 74.70 0.5393 32.195 104.362
5 172.54824 0.10000 1.000000 0.00 0.0000 31.536 0.000
6 28.65907 3.06660 1.595220 67.74 0.5442 27.994 77.200
7 72.68730 (variable) 1.000000 0.00 0.0000 27.224 0.000

8 109.54199 0.45000 2.049760 27.07 0.6050 11.149 -6.332
9 6.30521 2.67159 1.000000 0.00 0.0000 8.896 0.000
10 -20.73296 0.40000 2.001000 29.13 0.5997 8.800 -14.751
11 53.29359 0.12000 1.000000 0.00 0.0000 8.895 0.000
12 12.98841 2.97257 1.959060 17.47 0.6599 9.169 6.458
13 -10.77616 0.40000 2.001000 29.13 0.5997 8.939 -8.633
14 46.32169 (variable) 1.000000 0.00 0.0000 8.663 0.000

15 0.00000 1.00000 1.000000 0.00 0.0000 14.140 0.000
* 16 11.59572 4.79325 1.583126 59.38 0.5423 15.380 14.523
* 17 -27.01027 0.37924 1.000000 0.00 0.0000 15.017 0.000
18 22.25098 0.55000 2.000690 25.46 0.6133 13.407 -28.283
19 12.35245 (variable) 1.000000 0.00 0.0000 12.585 0.000

* 20 12.61009 3.17996 1.553320 71.68 0.5402 10.889 12.344
21 -13.65801 0.50000 1.959060 17.47 0.6599 10.491 -57.479
22 -18.40403 (variable) 1.000000 0.00 0.0000 10.507 0.000

23 42.00644 0.40000 1.772499 49.60 0.5521 7.323 -10.254
24 6.66370 0.95926 1.000000 0.00 0.0000 6.851 0.000
25 31.13861 2.34913 1.595509 39.24 0.5804 6.892 8.341
26 -5.78382 0.50000 1.883000 40.80 0.5652 6.935 -15.943
27 -10.17543 (variable) 1.000000 0.00 0.0000 7.190 0.000

28 0.00000 1.43000 1.516330 64.14 0.5352 20.000 0.000
29 0.00000 3.81000 1.000000 0.00 0.0000 20.000 0.000



Aspheric data 16th surface
K = 2.37028e-001 A 4 = -1.42457e-004 A 6 = -6.60905e-007 A 8 = -9.97083e-009 A10 = -6.31625e-011

17th page
K = 1.68394e + 001 A 4 = 8.73687e-005 A 6 = 4.79333e-007 A 8 = -1.80989e-008 A10 = 3.23788e-010

20th page
K = -9.61225e-001 A 4 = -2.77221e-005 A 6 = -3.85729e-007 A 8 = 2.39500e-009

Various data Zoom ratio 32.99
Wide angle Medium Telephoto focal length 4.27 40.35 140.77
F number 1.60 2.70 4.90
Half angle of view 35.11 4.25 1.22
Image height 3.00 3.00 3.00
Total lens length 90.02 90.02 90.02
BF 3.81 3.81 3.81

d 7 0.60 20.80 25.85
d14 27.05 6.85 1.80
d19 13.81 4.62 20.91
d24 9.15 18.34 2.05
d26 3.81 3.81 3.81

Zoom lens group data group Start surface Focal length
1 1 37.07
2 8 -5.43
3 15 27.98
4 20 19.24
5 25 ∞


Numerical Example 4
Unit mm


Surface number ri di ndi vdi θgFi Effective diameter Focal length
1 57.89080 1.25000 2.001000 29.13 0.5997 40.146 -80.708
2 33.47136 6.51729 1.438750 94.93 0.5343 37.370 80.711
3 550.57118 0.15000 1.000000 0.00 0.0000 36.676 0.000
4 37.79486 4.43480 1.537750 74.70 0.5393 33.492 78.840
5 325.38943 0.10000 1.000000 0.00 0.0000 32.696 0.000
6 26.42854 3.65336 1.595220 67.74 0.5442 27.914 66.096
7 75.81076 (variable) 1.000000 0.00 0.0000 26.860 0.000

8 55.83740 0.45000 2.095000 29.59 0.5946 11.093 -5.901
9 5.80918 2.79591 1.000000 0.00 0.0000 8.648 0.000
10 -18.77440 0.40000 2.049760 27.07 0.6050 8.550 -11.750
11 37.29651 0.12000 1.000000 0.00 0.0000 8.681 0.000
12 14.15312 2.24522 2.102050 16.77 0.6721 8.984 7.577
13 -19.30823 0.34000 1.953750 32.32 0.5898 8.854 -15.418
14 64.17496 (variable) 1.000000 0.00 0.0000 8.674 0.000

15 0.00000 1.00000 1.000000 0.00 0.0000 12.333 0.000
* 16 10.52235 4.21817 1.583126 59.38 0.5423 13.359 14.551
* 17 -38.12444 0.10000 1.000000 0.00 0.0000 12.887 0.000
18 19.38666 0.50000 2.001000 29.13 0.5997 11.966 -24.681
19 10.76008 (variable) 1.000000 0.00 0.0000 11.246 0.000

* 20 24.86622 1.12354 1.553320 71.68 0.5402 10.451 148.156
21 35.06663 0.10000 1.000000 0.00 0.0000 10.480 0.000
22 14.83225 1.00000 1.959060 17.47 0.6599 10.629 -49.414
23 10.95574 3.00110 1.487490 70.23 0.5300 10.283 15.074
24 -20.51879 (variable) 1.000000 0.00 0.0000 10.263 0.000

25 0.00000 1.43000 1.516330 64.14 0.5352 20.000 0.000
26 0.00000 3.81000 1.000000 0.00 0.0000 20.000 0.000

Aspheric data 16th surface
K = 3.85607e-001 A 4 = -1.42598e-004 A 6 = -6.57237e-007 A 8 = -1.18862e-008 A10 = -1.86282e-011

17th page
K = 1.75265e + 001 A 4 = 9.65341e-005 A 6 = 3.79021e-007 A 8 = -1.38403e-008 A10 = 3.39258e-010

20th page
K = -1.61300e + 000 A 4 = -3.24761e-005 A 6 = -4.83665e-007 A 8 = 3.68230e-009

Various data Zoom ratio 33.99
Wide angle Medium Telephoto focal length 4.24 40.50 144.09
F number 1.70 2.90 4.90
Half angle of view 35.29 4.24 1.19
Image height 3.00 3.00 3.00
Total lens length 90.05 90.05 90.05
BF 3.81 3.81 3.81

d 7 0.60 21.00 26.10
d14 27.30 6.90 1.80
d19 13.99 4.58 21.36
d24 9.42 18.83 2.05
d26 3.81 3.81 3.81

Zoom lens group data group Start surface Focal length
1 1 37.28
2 8 -5.41
3 15 27.73
4 20 19.76
5 25 ∞


Numerical Example 5
Unit mm


Surface number ri di ndi vdi θgFi Effective diameter Focal length
1 64.08879 1.25000 1.846660 23.78 0.6205 37.659 -113.379
2 38.23545 5.16882 1.496999 81.54 0.5374 35.660 81.400
3 633.48110 0.15000 1.000000 0.00 0.0000 35.046 0.000
4 42.09213 3.28596 1.537750 74.70 0.5393 32.309 102.707
5 170.36256 0.10000 1.000000 0.00 0.0000 31.647 0.000
6 29.24863 3.02517 1.595220 67.74 0.5442 28.140 79.281
7 73.53551 (variable) 1.000000 0.00 0.0000 27.365 0.000

8 113.03301 0.45000 2.095000 29.59 0.5946 11.032 -6.246
9 6.48579 2.61285 1.000000 0.00 0.0000 8.899 0.000
10 -20.26858 0.40000 2.001000 29.13 0.5997 8.806 -15.346
11 66.27493 0.12000 1.000000 0.00 0.0000 8.906 0.000
12 13.36750 2.74040 1.959060 17.47 0.6599 9.170 6.956
13 -12.29399 0.40000 2.001000 29.13 0.5997 8.960 -9.697
14 48.74688 (variable) 1.000000 0.00 0.0000 8.708 0.000

15 0.00000 1.00000 1.000000 0.00 0.0000 13.258 0.000
* 16 11.46823 4.33476 1.583126 59.38 0.5423 14.302 14.670
* 17 -29.43126 0.52205 1.000000 0.00 0.0000 13.963 0.000
18 21.06345 0.55000 2.000690 25.46 0.6133 12.536 -27.849
19 11.88590 (variable) 1.000000 0.00 0.0000 11.801 0.000

* 20 12.60831 3.09834 1.553320 71.68 0.5402 10.337 12.385
21 -13.79592 0.50000 1.959060 17.47 0.6599 10.117 -61.205
22 -18.28259 (variable) 1.000000 0.00 0.0000 10.140 0.000

23 32.10649 0.40000 1.772499 49.60 0.5521 7.071 -10.449
24 6.43984 0.96666 1.000000 0.00 0.0000 6.626 0.000
25 36.21957 2.30164 1.595509 39.24 0.5804 6.668 8.156
26 -5.51407 0.50000 1.883000 40.80 0.5652 6.726 -15.016
27 -9.80208 (variable) 1.000000 0.00 0.0000 7.000 0.000

28 0.00000 1.43000 1.516330 64.14 0.5352 20.000 0.000
29 0.00000 3.81000 1.000000 0.00 0.0000 20.000 0.000



Aspheric data 16th surface
K = -9.89828e-001 A 4 = -3.19949e-005 A 6 = 1.81512e-007

17th page
K = 0.00000e + 000 A 4 = 2.94380e-005 A 6 = 2.59285e-007 A 8 = -1.34039e-009

20th page
K = -1.55486e + 000 A 4 = -2.68000e-005 A 6 = -1.02568e-007

Various data Zoom ratio 35.00
Wide angle Medium Telephoto focal length 4.18 39.13 146.14
F number 1.70 3.00 5.00
Half angle of view 35.69 4.38 1.18
Image height 3.00 3.00 3.00
Total lens length 85.19 85.19 85.19
BF 3.81 3.81 3.81

d 7 0.60 23.17 28.81
d14 30.01 7.44 1.80
d19 9.67 3.93 12.46
d22 4.79 10.54 2.00
d27 1.00 1.00 1.00
d29 3.81 3.81 3.81

Zoom lens group data group Start surface Focal length
1 1 40.15
2 8 -5.41
3 15 24.93
4 20 15.46
5 23 -35.01
6 28 ∞


Numerical Example 6
Unit mm


Surface number ri di ndi vdi θgFi Effective diameter Focal length
1 84.74963 1.25000 1.854780 24.80 0.6121 45.501 -122.197
2 46.66447 6.19961 1.496999 81.54 0.5374 43.090 95.063
3 2934.01720 0.15000 1.000000 0.00 0.0000 42.474 0.000
4 52.01840 3.85800 1.537750 74.70 0.5393 38.983 120.853
5 250.66748 0.10000 1.000000 0.00 0.0000 38.324 0.000
6 31.69913 3.83474 1.595220 67.74 0.5442 33.377 84.826
7 80.84254 (variable) 1.000000 0.00 0.0000 32.525 0.000

8 97.24833 0.45000 2.049760 27.07 0.6050 12.900 -7.091
9 6.95356 3.11085 1.000000 0.00 0.0000 10.113 0.000
10 -22.44414 0.40000 2.001000 29.13 0.5997 9.997 -14.014
11 38.56982 0.12000 1.000000 0.00 0.0000 10.115 0.000
12 15.43068 3.13407 1.959060 17.47 0.6599 10.443 7.664
13 -12.95816 0.40000 2.001000 29.13 0.5997 10.291 -12.823
14 9407.44625 (variable) 1.000000 0.00 0.0000 10.127 0.000

15 0.00000 1.00000 1.000000 0.00 0.0000 11.750 0.000
* 16 11.62935 3.94669 1.583126 59.38 0.5423 12.412 14.381
* 17 -26.68368 1.64362 1.000000 0.00 0.0000 12.027 0.000
18 31.42030 0.55000 2.000690 25.46 0.6133 10.381 -23.380
19 13.36274 (variable) 1.000000 0.00 0.0000 9.881 0.000

* 20 11.85959 2.67968 1.553320 71.68 0.5402 8.844 12.012
21 -14.00629 0.50000 1.959060 17.47 0.6599 8.698 -67.674
22 -18.10915 (variable) 1.000000 0.00 0.0000 8.727 0.000

23 12.40301 0.40000 1.772499 49.60 0.5521 6.777 -16.392
24 6.19204 1.12329 1.000000 0.00 0.0000 6.384 0.000
25 -148.37666 1.99323 1.595509 39.24 0.5804 6.392 9.593
26 -5.56069 0.50000 1.883000 40.80 0.5652 6.435 -13.443
27 -10.84870 (variable) 1.000000 0.00 0.0000 6.679 0.000

28 0.00000 1.43000 1.516330 64.14 0.5352 20.000 0.000
29 0.00000 3.81000 1.000000 0.00 0.0000 20.000 0.000



Aspheric data 16th surface
K = -9.40028e-001 A 4 = -2.51818e-005 A 6 = 1.08198e-007

17th page
K = 0.00000e + 000 A 4 = 5.44949e-005 A 6 = -3.53978e-008 A 8 = 7.65736e-010

20th page
K = -2.34640e + 000 A 4 = 2.62587e-005 A 6 = -5.56710e-007

Various data Zoom ratio 29.72
Wide angle Medium Telephoto focal length 4.05 35.27 120.24
F number 1.80 2.60 4.00
Half angle of view 36.56 4.86 1.43
Image height 3.00 3.00 3.00
Total lens length 89.99 89.99 89.99
BF 3.81 3.81 3.81

d 7 0.60 26.35 32.79
d14 33.99 8.24 1.80
d19 8.14 3.57 9.61
d22 3.67 8.24 2.20
d27 1.00 1.00 1.00
d29 3.81 3.81 3.81

Zoom lens group data group Start surface Focal length
1 1 45.94
2 8 -6.48
3 15 26.02
4 20 14.61
5 23 -35.00
6 28 ∞


Numerical Example 7


Surface number ri di ndi vdi θgFi Effective diameter Focal length
1 60.08176 1.25000 2.001000 29.13 0.5997 38.235 -80.646
2 34.20293 6.16396 1.438750 94.93 0.5343 35.783 77.842
3 30397.07275 0.15000 1.000000 0.00 0.0000 35.129 0.000
4 35.08053 4.49795 1.537750 74.70 0.5393 31.841 70.561
5 427.27146 0.10000 1.000000 0.00 0.0000 31.019 0.000
6 26.19462 3.69533 1.595220 67.74 0.5442 27.744 71.573
7 64.06860 (variable) 1.000000 0.00 0.0000 26.906 0.000

8 67.25871 0.45000 2.095000 29.59 0.5946 11.047 -6.108
9 6.10720 2.70757 1.000000 0.00 0.0000 8.762 0.000
10 -18.97626 0.40000 2.001000 29.13 0.5997 8.664 -11.943
11 33.37739 0.12000 1.000000 0.00 0.0000 8.784 0.000
12 14.03945 2.52447 1.959060 17.47 0.6599 9.070 7.728
13 -14.71906 0.34000 1.953750 32.32 0.5898 8.959 -15.822
14 -469.55474 (variable) 1.000000 0.00 0.0000 8.849 0.000

15 0.00000 1.00000 1.000000 0.00 0.0000 12.471 0.000
* 16 9.53734 3.99529 1.583126 59.38 0.5423 13.643 14.331
* 17 -58.96469 1.03330 1.000000 0.00 0.0000 13.255 0.000
18 19.72898 0.50000 2.001000 29.13 0.5997 11.725 -18.636
19 9.50553 (variable) 1.000000 0.00 0.0000 10.869 0.000

* 20 16.71297 1.95854 1.553320 71.68 0.5402 12.661 34.404
21 128.14021 0.10000 1.000000 0.00 0.0000 12.643 0.000
22 22.55982 1.00000 1.959060 17.47 0.6599 12.666 -55.386
23 15.54991 3.00110 1.487490 70.23 0.5300 12.296 19.784
24 -24.00049 (variable) 1.000000 0.00 0.0000 12.214 0.000

25 0.00000 1.43000 1.516330 64.14 0.5352 20.000 0.000
26 0.00000 3.81000 1.000000 0.00 0.0000 20.000 0.000


Aspheric data 16th surface
K = 1.62981e-001 A 4 = -1.44897e-004 A 6 = -8.16691e-007 A 8 = -5.55657e-010 A10 = -4.09671e-010

17th page
K = 2.08445e + 001 A 4 = 4.10419e-005 A 6 = 8.10593e-007 A 8 = -2.52410e-008 A10 = 1.34302e-010

20th page
K = -8.34319e-001 A 4 = -3.86594e-005 A 6 = 3.39029e-010 A 8 = -1.29681e-009

Various data Zoom ratio 29.99
Wide angle Medium Telephoto focal length 4.50 25.92 134.84
F number 1.60 2.40 4.20
Half angle of view 33.71 6.60 1.27
Image height 3.00 3.00 3.00
Total lens length 90.01 90.01 90.01
BF 3.81 3.81 3.81

d 7 0.60 17.31 24.47
d14 25.67 8.96 1.80
d19 13.68 6.71 21.46
d24 9.83 16.81 2.05
d26 3.81 3.81 3.81

Zoom lens group data group Start surface Focal length
1 1 36.00
2 8 -5.72
3 15 33.18
4 20 17.05
5 25 ∞


Table 1 shows the correspondence between each embodiment and each conditional expression described above.

L1 first lens group, L2 second lens group, L3 third lens group, L4 fourth lens group,
L5 5th lens group, SP stop, GB glass block, IP image plane

Claims (6)

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 rear group including two or more lens groups, and at the telephoto end compared to the wide-angle end A zoom lens in which at least the second lens group moves so that a distance between the first lens group and the second lens group is widened;
The first lens group has at least one negative lens and three positive lenses,
The second lens group includes at least one positive lens;
When the refractive index for the d-line of the material is N2na and the Abbe number for the d-line is νd2na
N2na> 2.3-0.01 · νd2na
1.75 <N2na <2.7
A zoom lens, comprising: at least one negative lens made of a material that satisfies the following conditions. The focal length of at least one negative lens in the second lens group is f2na,
When the focal length of the second lens group is f2,
0.5 <f2na / f2 <2.5
The zoom lens according to claim 1, wherein the following condition is satisfied. When the focal length of the first lens group is f1,
-10.0 <f1 / f2 <-5.3
The zoom lens according to claim 1, wherein the following condition is satisfied. When the focal length of the entire system at the wide angle end of the zoom lens is fw,
−1.8 <f2 / fw <−0.5
5.0 <f1 / fw <22.0
The zoom lens according to claim 1, wherein the following condition is satisfied. The partial dispersion ratio of at least one negative lens in the second lens group is θgfna,
When the partial dispersion ratio of at least one positive lens in the second lens group is θgfpa,
(Θgfpa−θgfna) / (νd2pa−νd2na) <− 5.0 × 10 −3
The zoom lens according to claim 1, wherein the following condition is satisfied. An image pickup apparatus comprising: the zoom lens according to claim 1; and a solid-state image pickup device that receives an image formed by the zoom lens.