JP5289691B2 - Imaging optical system and electronic imaging apparatus having the same - Google Patents

Description

  The present invention relates to an imaging optical system used for an extremely small imaging module and an electronic imaging apparatus having the imaging optical system.

  In recent years, digital cameras have become widespread as next-generation cameras that replace silver salt 35 mm film cameras. Recently, digital cameras have become increasingly smaller and thinner. Also, camera functions (hereinafter referred to as imaging modules) have been mounted on mobile phones that are becoming popular at the same time. In order to mount this imaging module on a mobile phone, the optical system must be smaller and thinner than the optical system of a digital camera. In particular, a zoom lens is required to be small and thin. However, zoom lenses that are small enough to be installed in mobile phones are not well known.

As typical means for reducing the size and thickness of the zoom lens, the following two means can be considered. That is,
A. A retractable lens barrel is used to house the optical system in the thickness (depth) direction of the housing. The collapsible lens barrel is a lens barrel having a structure in which an optical system protrudes from the camera case during photographing and is housed in the camera case when carried.
B. A bending optical system is employed to accommodate the optical system in the width direction or height direction of the casing. This bending optical system is an optical system configured to bend the optical path (optical axis) of the optical system with a reflective optical element such as a mirror or a prism.

  A conventional example using the means A is described in, for example, the following Patent Document 1, and a conventional example using the means B is, for example, described in the following Patent Document 2. .

JP 2002-365545 A JP 2003-43354 A

  However, in the configuration using the means A described in Patent Document 1, the number of lenses constituting the optical system or the number of moving lens groups is still large, and it is difficult to reduce the size and thickness of the housing.

  The configuration using the means B described in Patent Document 2 is easier to make the housing thinner than the case using the means A, but the amount of movement of the movable lens group at the time of zooming, The number of lenses constituting the system tends to increase. Therefore, it is not suitable for miniaturization in volume.

  The present invention has been made in view of the above-described conventional problems, and enables a compact and thin imaging optical system, and a compact, thin and wide angle, and various aberrations are corrected well. An object of the present invention is to provide an electronic imaging apparatus.

In order to achieve the above object, an image forming optical system according to the present invention is an image forming optical system having a plurality of lens groups, and the distance between adjacent lens groups changes when zooming . A positive lens group, a first negative lens group, a diaphragm, a second positive lens group, and a second negative lens group. One positive lens group and the first negative lens group are arranged, and the second positive lens group and the second negative lens group are arranged on the image side from the stop. When zooming, the most object side lens unit is fixed, and the first positive lens unit has a cemented lens formed by cementing a plurality of lenses,
In a Cartesian coordinate system in which the horizontal axis is Nd and the vertical axis is νd, a straight line represented by Nd = α × νd + β (where α = −0.017) is set.
The area defined by the straight line when the lower limit value is within the range of the conditional expression (1) and the straight line when the upper limit value is satisfied, and the area determined by the following conditional expressions (2) and (3) An imaging optical system including Nd and νd of at least one lens constituting the cemented lens.
1.45 <β <2.15 (1)
1.30 <Nd <2.00 (2)
15 <νd <50 (3)
Here, Nd represents a refractive index and represents an Abbe number.

  Further, when one lens in which Nd and νd are included in both the areas is a predetermined lens, the optical axis center thickness of the predetermined lens is larger than the optical axis center thicknesses of the other lenses constituting the cemented lens. Is also preferably thin.

Moreover, it is preferable that the following conditional expression is satisfied.
0.22 <t1 <2.0
However, t1 is the optical axis center thickness of the predetermined lens.

  Further, it is desirable that the cemented lens is a compound lens in which a resin is adhered and cured on the lens surface of one lens constituting the cemented lens.

  In addition, the cemented lens is preferably a compound lens formed by closely bonding glass to the lens surface of one lens constituting the cemented lens.

Further, the imaging optical system, it is preferable that the a lens group closest to the object side is the first positive zoom lens is a lens group.

Further, the imaging optical system, it is preferable that the a zoom lens is the most the lens group on the object side first lens unit of negative lens.

  The imaging optical system preferably has a bending prism.

The prism is preferably in the lens group closest to the object side.

The electronic imaging device of the present invention is obtained by capturing an image formed through the imaging optical system with any one of the imaging optical system of the present invention, the electronic imaging device, and the electronic imaging device. Image processing means for processing the obtained image data and outputting it as image data in which the shape of the image is changed. The imaging optical system is a zoom lens, and the zoom lens is in focus at an object point at infinity. It is characterized by satisfying the following conditional expression.
0.7 <y ₀₇ / (fw · tan ω _07w ) <0.96
However, y ₀₇ is y ₀₇ = 0.7y ₁₀ , where y ₁₀ is the distance (maximum image height) from the center to the farthest point in the effective imaging plane (in the plane where imaging is possible) of the electronic imaging device. expressed. Further, ω _07w is an angle with respect to the optical axis in the object point direction corresponding to the image point connecting from the center on the imaging surface at the wide angle end to the position of y ₀₇ .

  According to the present invention, it is possible to reduce both the volume and the thickness of the imaging optical system, and in the electronic imaging device of the present invention, it is possible to correct various aberrations and widen the angle. Coexistence is possible.

Prior to the description of the embodiments, the effects of the present invention will be described.
The imaging optical system of the present invention is a imaging optical system having a positive lens group, a negative lens group, and a stop. A positive lens group is disposed on the object side of the stop, and a plurality of positive lens groups are provided. The basic configuration is to have a cemented lens formed by cementing these lenses.

  As described above, in the imaging optical system of the present invention, the cemented lens is used for the positive lens group on the object side from the stop, so that the variation of the chromatic aberration of magnification at the time of zooming in the zoom lens can be easily suppressed. In addition, it is possible to sufficiently suppress the occurrence of color bleeding over the entire zoom range with a small number of lenses. Further, since the positive lens group (positive lens group closer to the object side than the stop) that tends to be thick can be made thinner, the distance from the surface top of the lens closest to the object side to the entrance pupil can be made shallower (shorter). As a result, it is possible to make the other lens group on the object side thinner than the stop.

When a straight line represented by Nd = α × νd + β (where α = −0.017) is set in an orthogonal coordinate system in which the horizontal axis is Nd and the vertical axis is νd,
The area defined by the straight line when the lower limit value is within the range of the conditional expression (1) and the straight line when the upper limit value is satisfied, and the area determined by the following conditional expressions (2) and (3) It is desirable that Nd and νd of at least one lens constituting the cemented lens are included.
1.45 <β <2.15 (1)
1.30 <Nd <2.00 (2)
15 <νd <50 (3)
Here, Nd represents a refractive index and νd represents an Abbe number.

  Here, the glass material means a lens material such as glass or resin. Further, as the cemented lens, a lens in which a plurality of lenses made of these glass materials selected as appropriate is cemented is used.

  If the lower limit value of conditional expression (1) is not reached, the refractive index is low, so the effect of providing an aspheric surface on the air contact surface side is small, and it becomes difficult to correct spherical aberration, coma aberration, and distortion aberration. Alternatively, since the Abbe number is low, the cemented lens can correct chromatic aberration with extremely weak refractive power, but it is difficult to ensure the Petzval sum correction effect.

  If the upper limit value of conditional expression (1) is exceeded, the correction level of chromatic aberration and Petzval sum is equivalent to that of a normal optical glass lens, and the features of the present invention cannot be obtained.

  If the lower limit of conditional expression (2) is not reached, the effect when an aspheric surface is provided on the air contact surface side is small, and it becomes difficult to correct spherical aberration, coma aberration, and distortion aberration.

  When the upper limit of conditional expression (2) is exceeded, in the case of a material containing organic matter, if the refractive index is too high, the temperature dispersion becomes too large and the optical characteristics due to the environment tend to become unstable. Also, the reflectivity becomes too high, and ghosting is likely to occur even if the coating is optimized.

  If the lower limit of conditional expression (3) is not reached, the cemented lens can correct chromatic aberration with a very weak refractive power, but it is difficult to have a Petzval sum correction effect.

  If the upper limit of conditional expression (3) is exceeded, it is necessary to increase the refractive power of the cemented lens in order to correct chromatic aberration, which is advantageous for correcting the Petzval sum, but the influence of the optical properties due to the environment of the material. It becomes easy to receive.

It is more preferable that the following conditional expression (1 ′) is satisfied.
1.48 <β <2.04 (1 ′)
Further, it is more preferable that the following conditional expression (1 ″) is satisfied.
1.50 <β <2.00 (1 ″)
It is more preferable that the following conditional expression (2 ′) is satisfied.
1.58 <Nd <1.95 (2 ')
Furthermore, it is more preferable that the following conditional expression (2 ″) is satisfied.
1.63 <Nd <1.87 (2 ″)
It is more preferable that the following conditional expression (3 ′) is satisfied.
20 <νd <45 (3 ′)
Furthermore, it is more preferable that the following conditional expression (3 ″) is satisfied.
25 <νd <40 (3 ″)

  The cemented lens is composed of a lens having the values of Nd and νd (hereinafter referred to as a “predetermined lens”) included in both of the above-mentioned areas and another lens, and the predetermined lens has an optical axis center thickness. It is preferably thinner than the center thickness of the optical axis of the other lens. By doing in this way, further excellent correction of the above aberrations and a reduction in the thickness of the lens group can be realized.

  The cemented lens is preferably a compound lens in which a resin is adhered and cured on the lens surface (other lens surface) in order to improve manufacturing accuracy. Here, the contact-cured resin corresponds to the predetermined lens.

  Further, the cemented lens is advantageous in terms of light resistance, chemical resistance, and the like, and is preferably a compound lens in which glass is adhered and cured on the lens surface (other lens surface). Here, the glass that has been subjected to close contact hardening corresponds to the predetermined lens.

In addition, when the cemented lens is molded in a small size and stably, the optical axis center thickness t1 of a predetermined lens (Nd and νd included in both the above regions) is expressed by the following conditional expression (4). It is good to satisfy.
0.22 <t1 <2.0 (4)
It is more preferable that the following conditional expression (4 ′) is satisfied.
0.3 <t1 <1.5 (4 ′)
Furthermore, it is more preferable that the following conditional expression (4 ″) is satisfied.
0.32 <t1 <1.0 (4 ")

  Further, the imaging optical system is preferably a zoom lens in which the most object side is a positive group from the viewpoint of increasing the zoom magnification and improving the brightness of the lens.

  In addition, the image forming optical system is preferably a zoom lens having a negative group on the most object side in view of miniaturization.

  Further, the imaging optical system preferably has a prism for bending in order to reduce the thickness of the optical system with respect to the photographing direction.

  In order to further reduce the thickness of the imaging optical system, it is preferable that the prism is in the group closest to the object side.

By the way, when the pixel size of the electronic image sensor becomes smaller than a certain level, the component having the Nyquist frequency or higher disappears due to the influence of diffraction. Therefore, if this is used, the optical low-pass filter can be omitted. This is also preferable from the viewpoint of making the entire optical system as thin as possible.
Therefore, it is preferable that the following conditional expression (6) is satisfied.
Fw ≧ a (μm) (6)
Here, Fw is the release F value at the wide-angle end, and a is the horizontal inter-pixel distance (unit: μm) of the electronic image sensor.
If the conditional expression (6) is satisfied, the optical low-pass filter need not be arranged in the optical path. Therefore, the optical system can be reduced in size.

  When the above condition (6) is satisfied, it is preferable that the aperture stop is only opened from the viewpoint of ensuring image quality. This means that the optical system in this case is an optical system in which the diameter of the aperture stop is always constant. Further, in the optical system in this case, a narrowing operation is not necessary, so that the narrowing mechanism can be omitted. Therefore, the size can be reduced accordingly. If the conditional expression (6) is not satisfied, an optical low-pass filter is necessary.

Moreover, it is more preferable that the conditional expression (6 ′) is satisfied.
Fw ≧ 1.2a (μm) (6 ′)
Furthermore, it is even more preferable that the conditional expression (6 ″) is satisfied.
Fw ≧ 1.4a (μm) (6 ″)

Finally, an electronic imaging device will be described. As the electronic imaging device, a device that achieves both a reduction in depth and a wide angle of view is preferable.
Here, it is assumed that an object at infinity is imaged by an optical system having no distortion. In this case, since the image formed has no distortion,
f = y / tan ω
Is established.
Where y is the height of the image point from the optical axis, f is the focal length of the imaging system, ω is the angle with respect to the optical axis in the object direction corresponding to the image point connecting from the center on the imaging surface to the y position. is there.

On the other hand, if the optical system has barrel distortion,
f> y / tan ω
It becomes. That is, if f and y are constant values, ω is a large value.

  Therefore, it is preferable to use a zoom lens as an imaging optical system in the electronic imaging apparatus. As the zoom lens, it is preferable to use an optical system that intentionally has a large barrel distortion, particularly at a focal length near the wide-angle end. In this case, it is possible to achieve a wider angle of view of the optical system as much as it is not necessary to correct distortion. However, the image of the object is formed on the electronic image pickup device in a state having barrel-shaped distortion. Therefore, in the electronic imaging device, image data obtained by the electronic imaging element is processed by image processing. In this processing, the image data (image shape) is changed so as to correct the barrel distortion. In this way, the finally obtained image data is image data having a shape substantially similar to the object. Therefore, an object image may be output to a CRT or printer based on the image data.

Here, it is preferable to use an imaging optical system (zoom lens) that satisfies the following conditional expression (7) when focusing on an object point at infinity.
0.7 <y ₀₇ / (fw · tan ω _07w ) <0.96 (7)
However, when y ₀₇ is the distance to the farthest point from the center in the effective image pickup plane of the electronic imaging device (imaging possible in-plane) (maximum image height) was y _10, the table as y ₀₇ = 0.7y ₁₀ Is done. Further, ω _07w is an angle with respect to the optical axis in the object point direction corresponding to the image point connecting from the center on the imaging surface at the wide angle end to the position of y ₀₇ .

  Conditional expression (7) defines the degree of barrel distortion at the zoom wide-angle end. If conditional expression (7) is satisfied, it becomes possible to capture information with a wide angle of view without enlarging the optical system. Note that an image distorted in a barrel shape is photoelectrically converted by an electronic imaging device, and becomes image data distorted in a barrel shape. However, the image data distorted into a barrel shape is electrically processed by an image processing means which is a signal processing system of the electronic imaging apparatus, corresponding to a change in the shape of the image. In this way, even if the image data finally output from the image processing means is reproduced on the display device, the distortion is corrected and an image substantially similar to the subject shape is obtained.

Here, when the value exceeds the upper limit value of the conditional expression (7), particularly when a value close to 1 is taken, correction corresponding to the fact that the distortion aberration is optically corrected is performed by the image processing means. However, it is difficult to capture an image over a wide viewing angle while maintaining downsizing of the optical system. On the other hand, if the lower limit value of conditional expression (7) is not reached, when the image distortion due to the distortion of the optical system is corrected by the image processing means, the stretching ratio in the radial direction around the angle of view becomes too high. As a result, the sharpness degradation at the periphery of the image becomes conspicuous.
On the other hand, when the conditional expression (7) is satisfied, the optical system can be downsized and widened (the angle of view in the vertical direction of distortion is 38 ° or more).

It is more preferable that the following conditional expression (7 ′) is satisfied.
0.75 <y ₀₇ / (fw · tan ω _07w ) <0.94 (7 ')
Furthermore, it is even more preferable that the following conditional expression (7 ″) is satisfied.
_{0.80 <y 07 / (fw ·} tanω 07w) <0.92 ... (7 ")

  The imaging optical system according to the present invention satisfies the above-described conditional expressions and structural characteristics individually or satisfies the requirements so that the volume of the imaging optical system can be reduced even when an electronic imaging device having a large number of pixels is used. This makes it possible to achieve both a reduction in thickness and thickness, and to achieve good aberration correction. In addition, the imaging optical system of the present invention can be provided with (satisfied with) the above conditional expressions and structural features in combination. In this case, further downsizing / thinning or better aberration correction can be achieved. In addition, the electronic imaging apparatus having the imaging optical system of the present invention can achieve both a reduction in volume and a reduction in volume of the imaging optical system. Can be achieved.

Next, embodiments of the present invention will be described with reference to the drawings. Examples 1, 2, 11, 20, and 21 are reference examples.
As the zoom lens of the present invention, a 5-group configuration or a 4-group configuration is conceivable. In a zoom lens having a five-group configuration, from the object side, a first lens group having a positive refractive power, a second lens group having a negative refractive power, a third lens group having a positive refractive power, a fourth lens group having a negative refractive power, and a positive refraction. It is preferable to arrange the lens groups in the order of the fifth lens group of the force.

  Here, the first lens group preferably includes a negative lens, a prism, and a cemented lens. At this time, it is more preferable to dispose these in the order of the negative lens, the prism, and the cemented lens from the object side. Further, it is preferable that the cemented lens is composed of a positive lens and a negative lens, and the cemented lens is arranged so that the negative lens is located on the object side. Note that the first lens group may be configured by only one negative lens, one prism, and one cemented lens. In this case, the cemented lens is composed of one positive lens and one negative lens.

  The second lens group preferably includes a positive lens and a negative lens. At this time, it is more preferable to dispose these in the order of the negative lens and the positive lens from the object side. Note that the second lens group may be composed of only one positive lens and one negative lens.

  The third lens group preferably includes a positive lens and a negative lens. At this time, it is more preferable to form a cemented lens with a positive lens and a negative lens, and arrange the cemented lens so that the positive lens is located on the object side. Note that the third lens group may be configured by only one cemented lens. In this case, the cemented lens is composed of one positive lens and one negative lens.

  The fourth lens group preferably includes a negative lens. At this time, it is more preferable that the fourth lens group is constituted by only one negative lens.

  The fifth lens group preferably includes a positive lens. At this time, it is more preferable that the fifth lens group is constituted by only one positive lens.

In another zoom lens having a five-group configuration, from the object 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 positive refractive power. It is preferable to dispose each lens group in the order of the group and the fifth lens group having positive refractive power. The zoom lens having this configuration is a reference example.

  Here, the first lens group preferably includes a positive lens and a negative lens. At this time, it is more preferable to form a cemented lens with a positive lens and a negative lens, and arrange the cemented lens so that the positive lens is located on the object side. Note that the first lens group may be composed of only one cemented lens. In this case, the cemented lens is composed of one positive lens and one negative lens.

  The second lens group preferably includes a negative lens, a prism, and a positive lens. At this time, it is more preferable to dispose these in the order of negative lens, prism, negative lens, and positive lens from the object side. Note that the second lens group may be composed of only two negative lenses, one prism, and one positive lens.

  The third lens group preferably includes a positive lens and a cemented lens. At this time, it is preferable to dispose a positive lens on the object side of the cemented lens. More preferably, the cemented lens is configured by a positive lens and a negative lens, and the cemented lens is disposed so that the positive lens is positioned on the object side. Note that the third lens group may be composed of only one positive lens and one cemented lens. In this case, the cemented lens is composed of one positive lens and one negative lens.

  The fourth lens group preferably includes a positive lens. At this time, it is more preferable that the fourth lens group is constituted by only one positive lens.

  The fifth lens group preferably includes a positive lens. At this time, it is more preferable that the fifth lens group is constituted by only one positive lens.

  Further, in the zoom lens having a four-group configuration, in order from the object side, a first lens group having a negative refractive power, a second lens group having a positive refractive power, a third lens group having a negative refractive power, and a fourth lens group having a positive refractive power. It is preferable to arrange the lens groups in this order.

  Here, the first lens group preferably includes a negative lens, a prism, and a cemented lens. At this time, it is more preferable to dispose these in the order of the negative lens, the prism, and the cemented lens from the object side. Further, it is preferable that the cemented lens is composed of a positive lens and a negative lens, and the cemented lens is arranged so that the positive lens is located on the object side. Note that the first lens group may be configured by only one negative lens, one prism, and one cemented lens. In this case, the cemented lens is composed of one positive lens and one negative lens.

  The second lens group preferably includes a positive lens and a negative lens. At this time, it is more preferable to form a cemented lens with a positive lens and a negative lens, and arrange the cemented lens so that the positive lens is located on the object side. Note that the second lens group may be constituted by only one cemented lens. In this case, the cemented lens is composed of one positive lens and one negative lens.

  The third lens group preferably includes a positive lens and a negative lens. At this time, it is more preferable to form a cemented lens with a positive lens and a negative lens, and arrange the cemented lens so that the negative lens is located on the object side. Note that the third lens group may be configured by only one cemented lens. In this case, the cemented lens is composed of one positive lens and one negative lens.

  The fourth lens group preferably includes a positive lens and a negative lens. At this time, it is more preferable to form a cemented lens with a positive lens and a negative lens, and arrange the cemented lens so that the positive lens is located on the object side. Note that the fourth lens group may be composed of only one cemented lens. In this case, the cemented lens is composed of one positive lens and one negative lens.

In another zoom lens having a four-group configuration, in order from the object 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 positive refractive power. It is preferable to arrange the lens groups in the order of lens groups. The zoom lens having this configuration is a reference example.

  Here, the first lens group preferably includes a positive lens and a negative lens. At this time, it is more preferable to form a cemented lens with a positive lens and a negative lens, and arrange the cemented lens so that the positive lens is located on the object side. Note that the first lens group may be composed of only one cemented lens. In this case, the cemented lens is composed of one positive lens and one negative lens.

  The second lens group preferably includes a positive lens and a negative lens. At this time, it is more preferable to dispose the negative lens, the negative lens, and the positive lens in this order from the object side. Note that the second lens group may be composed of only one positive lens and two negative lenses.

  The third lens group preferably includes a positive lens and a cemented lens. At this time, it is preferable to dispose a positive lens on the object side of the cemented lens. More preferably, the cemented lens is configured by a positive lens and a negative lens, and the cemented lens is disposed so that the positive lens is positioned on the object side. Note that the third lens group may be composed of only one positive lens and one cemented lens. In this case, the cemented lens is composed of one positive lens and one negative lens.

  The fourth lens group preferably includes a positive lens. At this time, it is more preferable that the fourth lens group is constituted by only one positive lens.

  In addition, the refractive power of one lens can be distributed to two lenses. Therefore, in each lens group described above, one lens can be replaced with two lenses. However, from the viewpoint of size reduction and thickness reduction, it is preferable that the number of lenses replaced with two lenses is only one in each lens group.

  FIG. 1 is a cross-sectional view along the optical axis showing an optical configuration at the time of focusing on an object point at infinity at the wide angle end of a zoom lens according to Embodiment 1 of the present invention.

  FIG. 2 is a diagram showing spherical aberration, astigmatism, distortion, and lateral chromatic aberration when the zoom lens according to Example 1 is focused on an object point at infinity, where (a) is a wide angle end, (b) is an intermediate, (c) shows the state at the telephoto end.

  As shown in FIG. 1, the zoom lens according to the first embodiment includes, in order from the object side, a first lens group G1, a second lens group G2, an aperture stop S, a third lens group G3, and a fourth lens group. G4 and the fifth lens group G5 are included. In FIG. 1, LPF is a low-pass filter, CG is a cover glass, and I is an imaging surface of an electronic image sensor.

  The first lens group G1 includes a negative meniscus lens L111 having a convex surface facing the object side, a prism L112, and a cemented lens of a negative meniscus lens L113 having a convex surface facing the object side and a biconvex lens L114. It has a refractive power of

  The second lens group G2 includes a biconcave lens L121 and a positive meniscus lens L122 having a convex surface directed toward the object side, and has a negative refracting power as a whole.

  The third lens group G3 is composed of a cemented lens made up of a biconvex lens L131 and a biconcave lens L132, and has a positive refractive power as a whole.

  The fourth lens group G4 includes a negative meniscus lens L141 having a convex surface directed toward the object side, and has a negative refracting power as a whole.

  The fifth lens group G5 includes a biconvex lens L142, and has a positive refractive power as a whole.

  When zooming from the wide-angle end to the telephoto end, the first lens group G1 is fixed, the second lens group G2 is moved to the image side, the aperture stop S is fixed, and the third lens group G3 is moved to the object side. The fourth lens group G4 once moves to the image side, then moves to the object side, and moves to the image side of the fifth lens group G5.

  The aspherical surfaces are the object-side surface of the negative meniscus lens L113 with the convex surface facing the object side in the first lens group G1, both surfaces of the biconcave lens L121 in the second lens group G2, and the biconvex lens in the third lens group G3. It is provided on the object side surface of L131, the image side surface of the biconcave lens L132, and the object side surface of the biconvex lens L142 in the fifth lens group G5.

Next, numerical data of optical members constituting the zoom lens of Example 1 are shown.
In the numerical data of Example 1, r1, r2,... Are the radius of curvature of each lens surface, d1, d2,... Are the thickness or air spacing of each lens, and nd1, nd2,. Are the Abbe number of each lens, Fno. Is the F number, f is the focal length of the entire system, and D0 is the distance from the object to the first surface. FIG. 48 shows the relationship between the r and d numbers in the numerical data and the optical configuration (lens surface, thickness, air spacing).

The aspherical shape is expressed by the following equation when the optical axis direction is z, the direction orthogonal to the optical axis is y, the conical coefficient is K, and the aspherical coefficients are A4, A6, A8, and A10. .
z = (y ² / r) / [1+ {1− (1 + K) (y / r) ² } ^1/2 ]
+ A4y ⁴ + A6y ⁶ + A8y ⁸ + A10y ¹⁰
E represents a power of 10. The symbols of these specification values are common to the numerical data of the examples described later. The cone coefficient may be indicated by k.

Next, numerical data (specific values) of this embodiment will be listed.
Numerical data 1
r1 = 24.248
d1 = 1 Nd1 = 1.8061 νd1 = 40.92
r2 = 10.001
d2 = 2.9
r3 = ∞
d3 = 12 Nd3 = 1.8061 νd3 = 40.92
r4 = ∞
d4 = 0.3
r5 = 17.436 (aspherical surface)
d5 = 0.04 Nd5 = 1.4223 νd5 = 71.23
r6 = 14.53
d6 = 2.85 Nd6 = 1.64 νd6 = 60.08
r7 = -35.328
d7 = D7
r8 = -93.536 (aspherical surface)
d8 = 0.8 Nd8 = 1.8061 νd8 = 40.92
r9 = 4.780 (Aspherical surface)
d9 = 0.7
r10 = 7.225
d10 = 2.2 Nd10 = 1.7891 νd10 = 26.46
r11 = 130.621
d11 = D11
r12 = aperture
d12 = D12
r13 = 9.120 (Aspherical surface)
d13 = 5.27 Nd13 = 1.7432 νd13 = 49.34
r14 = -8.739
d14 = 1 Nd14 = 1.84666 νd14 = 23.78
r15 = 48.952 (aspherical surface)
d15 = D15
r16 = 52.531
d16 = 0.6 Nd16 = 1.48749 νd16 = 70.23
r17 = 10.032
d17 = D17
r18 = 9.526 (aspherical surface)
d18 = 1.8 Nd18 = 1.7432 νd18 = 49.34
r19 = -210.018
d19 = D19
r20 = ∞
d20 = 1.9 Nd20 = 1.54771 νd20 = 62.84
r21 = ∞
d21 = 0.8
r22 = ∞
d22 = 0.75 Nd22 = 1.51633 νd22 = 64.14
r23 = ∞
d23 = D23

Aspherical coefficient fifth surface
k = 0
A4 = -2.15976E-05
A6 = 2.52116E-07
A8 = 0.000E + 00
8th page
k = 0
A4 = -7.56610E-05
A6 = 6.51952E-06
A8 = -3.16898E-08
9th page
k = 0
A4 = -9.93782E-04
A6 = -1.69856E-06
A8 = -1.53302E-06
13th page
k = 0
A4 = 1.36218E-04
A6 = 2.38102E-06
A8 = 4.64145E-08
15th page
k = 0
A4 = 5.09744E-04
A6 = 4.41229E-06
A8 = 4.02078E-07
18th page
k = 0
A4 = -9.97174E-05
A6 = 6.62010E-07
A8 = -4.53426E-08

Zoom data
When D0 (distance from the object to the first surface) is ∞
Wide-angle end Middle Telephoto end
Focal length 6 13.7 18
FNO. 2.86 4.58 5.61
D7 0.8 6.32 7.47
D11 8.07 2.55 1.4
D12 10.44 3.94 1.2
D15 1.2 14.4 18.37
D17 2.99 0.2 0.2
D19 5.64 1.74 0.5
D23 1.36 1.36 1.36

  FIG. 3 is a cross-sectional view along the optical axis showing the optical configuration at the time of focusing on an object point at infinity at the wide angle end of the zoom lens according to Example 2 of the present invention.

  4A and 4B are diagrams showing spherical aberration, astigmatism, distortion aberration, and chromatic aberration of magnification when the zoom lens according to Example 2 is focused on an object point at infinity, where (a) is a wide-angle end, (b) is an intermediate position, (c) shows the state at the telephoto end.

  As shown in FIG. 3, the zoom lens of Example 2 includes, in order from the object side, the first lens group G1, the second lens group G2, the aperture stop S, the third lens group G3, and the fourth lens group. G4 and the fifth lens group G5 are included. In the figure, LPF is a low-pass filter, CG is a cover glass, and I is an image pickup surface of an electronic image pickup element.

  The first lens group G1 includes a negative meniscus lens L111 having a convex surface facing the object side, a prism L112, and a cemented lens of a negative meniscus lens L113 having a convex surface facing the object side and a biconvex lens L114. It has a refractive power of

  The second lens group G2 includes a biconcave lens L121 and a positive meniscus lens L122 having a convex surface directed toward the object side, and has a negative refracting power as a whole.

  The third lens group G3 is composed of a cemented lens made up of a biconvex lens L131 and a biconcave lens L132, and has a positive refractive power as a whole.

  The fourth lens group G4 includes a negative meniscus lens L141 having a convex surface directed toward the object side, and has a negative refracting power as a whole.

  The fifth lens group G5 includes a biconvex lens L142, and has a positive refractive power as a whole.

  When zooming from the wide-angle end to the telephoto end, the first lens group G1 is fixed, the second lens group G2 is moved to the image side, the aperture stop S is fixed, and the third lens group G3 is moved to the object side. The fourth lens group G4 once moves to the image side, then moves to the object side, and moves to the image side of the fifth lens group G5.

  The aspherical surfaces are the object-side surface of the negative meniscus lens L113 with the convex surface facing the object side in the first lens group G1, both surfaces of the biconcave lens L121 in the second lens group G2, and the biconvex lens in the third lens group G3. It is provided on the object side surface of L131, the image side surface of the biconcave lens L132, and the object side surface of the biconvex lens L142 in the fifth lens group G5.

Next, numerical data of this embodiment will be listed.
Numerical data 2
r1 = 22.626
d1 = 1 Nd1 = 1.8061 νd1 = 40.92
r2 = 9.106
d2 = 2.9
r3 = ∞
d3 = 12 Nd3 = 1.8061 νd3 = 40.92
r4 = ∞
d4 = 0.3
r5 = 17.726 (aspherical surface)
d5 = 0.1 Nd5 = 1.51556 νd5 = 37.55
r6 = 14.634
d6 = 3.54 Nd6 = 1.741 νd6 = 52.64
r7 = -68.354
d7 = D7
r8 = -53.548 (aspherical surface)
d8 = 0.8 Nd8 = 1.8061 νd8 = 40.92
r9 = 6.011 ASP
d9 = 0.7
r10 = 8.348
d10 = 2.2 Nd10 = 1.7552 νd10 = 27.51
r11 = 184.11
d11 = D11
r12 = aperture d12 = D12
r13 = 8.334 (aspherical surface)
d13 = 6.65 Nd13 = 1.6935 νd13 = 53.21
r14 = -10.475
d14 = 1 Nd14 = 1.84666 νd14 = 23.78
r15 = 46.448 (aspherical surface)
d15 = D15
r16 = 24.994
d16 = 0.6 Nd16 = 1.48749 νd16 = 70.23
r17 = 9.936
d17 = D17
r18 = 12.072 (aspherical surface)
d18 = 1.8 Nd18 = 1.7432 νd18 = 49.34
r19 = -117.168
d19 = D19
r20 = ∞
d20 = 1.9 Nd20 = 1.54771 νd20 = 62.84
r21 = ∞
d21 = 0.8
r22 = ∞
d22 = 0.75 Nd22 = 1.51633 νd22 = 64.14
r23 = ∞
d23 = D23

Aspherical coefficient fifth surface
k = 0
A4 = 3.01704E-05
A6 = -5.98265E-09
A8 = 0
8th page
k = 0
A4 = 3.17863E-04
A6 = -8.85684E-06
A8 = 1.43419E-07
9th page
k = 0
A4 = -4.51850E-05
A6 = -1.39061E-05
A8 = -1.48871E-07
13th page
k = 0
A4 = 5.18168E-05
A6 = 1.83538E-06
A8 = 2.12160E-08
15th page
k = 0
A4 = 5.14144E-04
A6 = 9.05366E-06
A8 = 5.27757E-07
18th page
k = 0
A4 = -9.15346E-05
A6 = 7.74036E-06
A8 = -1.56594E-07

Zoom data
When D0 (distance from the object to the first surface) is ∞
Wide-angle end Middle Telephoto end
Focal length 6.101 13.423 17.998
FNO. 3.29 4.99 6.1
D7 0.72 5.29 5.98
D11 14.46 3.61 0.82
D12 5.92 2.63 1.08
D15 1.26 11.85 14.85
D17 1.42 1.6 2.93
D19 4.82 1.38 0.4
D23 1.36 1.36 1.36

  FIG. 5 is a sectional view along the optical axis showing an optical configuration at the time of focusing on an object point at infinity at the wide-angle end of the zoom lens according to Example 3 of the present invention.

  FIG. 6 is a diagram illustrating spherical aberration, astigmatism, distortion, and lateral chromatic aberration when the zoom lens according to Example 3 is focused on an object point at infinity, where (a) is a wide angle end, (b) is an intermediate position, (c) shows the state at the telephoto end.

  As shown in FIG. 5, the zoom lens of Example 3 includes, in order from the object side, the first lens group G1, the second lens group G2, the aperture stop S, the third lens group G3, and the fourth lens group. G4 and the fifth lens group G5 are included. In the figure, LPF is a low-pass filter, CG is a cover glass, and I is an image pickup surface of an electronic image pickup element.

  The first lens group G1 includes a negative meniscus lens L111 having a convex surface facing the object side, a prism L112, and a cemented lens of a negative meniscus lens L113 having a convex surface facing the object side and a biconvex lens L114. It has a refractive power of

  The second lens group G2 includes a biconcave lens L121 and a positive meniscus lens L122 having a convex surface directed toward the object side, and has a negative refracting power as a whole.

  The third lens group G3 is composed of a cemented lens made up of a biconvex lens L131 and a biconcave lens L132, and has a positive refractive power as a whole.

  The fourth lens group G4 includes a negative meniscus lens L141 having a convex surface directed toward the object side, and has a negative refracting power as a whole.

  The fifth lens group G5 includes a biconvex lens L142, and has a positive refractive power as a whole.

  When zooming from the wide-angle end to the telephoto end, the first lens group G1 is fixed, the second lens group G2 is moved to the image side, the aperture stop S is fixed, and the third lens group G3 is moved to the object side. The fourth lens group G4 once moves to the image side, then moves to the object side, and moves to the image side of the fifth lens group G5.

  The aspherical surfaces are the object-side surface of the negative meniscus lens L113 with the convex surface facing the object side in the first lens group G1, both surfaces of the biconcave lens L121 in the second lens group G2, and the biconvex lens in the third lens group G3. It is provided on the object side surface of L131, the image side surface of the biconcave lens L132, and the object side surface of the positive biconvex lens L142 in the fifth lens group G5.

Next, numerical data of this embodiment will be listed.
Numerical data 3
r1 = 27.441
d1 = 1 Nd1 = 1.8061 νd1 = 40.92
r2 = 9.71
d2 = 3.4
r3 = ∞
d3 = 12 Nd3 = 1.8061 νd3 = 40.92
r4 = ∞
d4 = 0.3
r5 = 19.931 (Aspherical surface)
d5 = 0.1 Nd5 = 1.41144 νd5 = 16.88
r6 = 16.936
d6 = 3.54 Nd6 = 1.741 νd6 = 52.64
r7 = -44.455
d7 = D7
r8 = -56.792 (aspherical surface)
d8 = 0.8 Nd8 = 1.8061 νd8 = 40.92
r9 = 5.693 ASP
d9 = 0.7
r10 = 7.891
d10 = 2.2 Nd10 = 1.7552 νd10 = 27.51
r11 = 160.04
d11 = D11
r12 = aperture d12 = D12
r13 = 8.361 (aspherical surface)
d13 = 6.75 Nd13 = 1.6935 νd13 = 53.21
r14 = -10.323
d14 = 1 Nd14 = 1.84666 νd14 = 23.78
r15 = 45.411 (aspherical surface)
d15 = D15
r16 = 59.354
d16 = 0.6 Nd16 = 1.48749 νd16 = 70.23
r17 = 13.151
d17 = D17
r18 = 12.348 (aspherical surface)
d18 = 1.8 Nd18 = 1.7432 νd18 = 49.34
r19 = -102.32
d19 = D19
r20 = ∞
d20 = 1.9 Nd20 = 1.54771 νd20 = 62.84
r21 = ∞
d21 = 0.8
r22 = ∞
d22 = 0.75 Nd22 = 1.51633 νd22 = 64.14
r23 = ∞
d23 = D23

Aspherical coefficient fifth surface
k = 0
A4 = 1.46669E-05
A6 = -3.94855E-08
A8 = 0
8th page
k = 0
A4 = 3.37316E-04
A6 = -1.04839E-05
A8 = 1.75467E-07
9th page
k = 0
A4 = -7.63457E-05
A6 = -1.58081E-05
A8 = -3.21104E-07
13th page
k = 0
A4 = 5.44923E-05
A6 = 1.84341E-06
A8 = 1.58485E-08
15th page
k = 0
A4 = 5.11206E-04
A6 = 9.111112E-06
A8 = 5.37429E-07
18th page
k = 0
A4 = -1.20419E-04
A6 = 6.69235E-06
A8 = -1.25817E-07

Zoom data
When D0 (distance from the object to the first surface) is ∞
Wide-angle end Middle Telephoto end
Focal length 6.1 13.42 17.995
FNO. 3.28 4.91 5.92
D7 2.17 6.92 8.06
D11 14.74 3.82 0.98
D12 6.44 2.77 0.97
D15 1.26 11.25 13.71
D17 1.42 1.61 2.93
D19 4.82 1.38 0.4
D23 1.36 1.36 1.36

  FIG. 7 is a cross-sectional view along the optical axis showing an optical configuration at the time of focusing on an object point at infinity at the wide-angle end of a zoom lens according to Example 4 of the present invention.

  FIG. 8 is a diagram illustrating spherical aberration, astigmatism, distortion, and chromatic aberration of magnification when the zoom lens according to Example 4 is focused on an object point at infinity, where (a) is the wide-angle end, (b) is the middle, (c) shows the state at the telephoto end.

  As shown in FIG. 7, the zoom lens of Example 4 includes, in order from the object side, the first lens group G1, the second lens group G2, the aperture stop S, the third lens group G3, and the fourth lens group. G4 and the fifth lens group G5 are included. In the figure, LPF is a low-pass filter, CG is a cover glass, and I is an image pickup surface of an electronic image pickup element.

  The first lens group G1 includes a negative meniscus lens L111 having a convex surface facing the object side, a prism L112, and a cemented lens of a negative meniscus lens L113 having a convex surface facing the object side and a biconvex lens L114. It has a refractive power of

  The second lens group G2 includes a biconcave lens L121 and a positive meniscus lens L122 having a convex surface directed toward the object side, and has a negative refracting power as a whole.

  The third lens group G3 is composed of a cemented lens made up of a biconvex lens L131 and a biconcave lens L132, and has a positive refractive power as a whole.

  The fourth lens group G4 includes a negative meniscus lens L141 having a convex surface directed toward the object side, and has a negative refracting power as a whole.

  The fifth lens group G5 includes a biconvex lens L142, and has a positive refractive power as a whole.

  When zooming from the wide-angle end to the telephoto end, the first lens group G1 is fixed, the second lens group G2 is moved to the image side, the aperture stop S is fixed, and the third lens group G3 is moved to the object side. The fourth lens group G4 once moves to the image side, then moves to the object side, and moves to the image side of the fifth lens group G5.

  The aspherical surfaces are the object-side surface of the negative meniscus lens L113 with the convex surface facing the object side in the first lens group G1, both surfaces of the biconcave lens L121 in the second lens group G2, and the biconvex lens in the third lens group G3. It is provided on the object side surface of L131, the image side surface of the biconcave lens L132, and the object side surface of the biconvex lens L142 in the fifth lens group G5.

Next, numerical data of this embodiment will be listed.
Numerical data 4
r1 = 25.154
d1 = 1 Nd1 = 1.8061 νd1 = 40.92
r2 = 9.496
d2 = 2.9
r3 = ∞
d3 = 12 Nd3 = 1.8061 νd3 = 40.92
r4 = ∞
d4 = 0.3
r5 = 19.469 (aspherical surface)
d5 = 0.1 Nd5 = 1.5511 νd5 = 20.02
r6 = 16.48
d6 = 3.54 Nd6 = 1.741 νd6 = 52.64
r7 = -46.438
d7 = D7
r8 = -50.883 (Aspherical surface)
d8 = 0.8 Nd8 = 1.8061 νd8 = 40.92
r9 = 5.666 ASP
d9 = 0.7
r10 = 7.913
d10 = 2.2 Nd10 = 1.7552 νd10 = 27.51
r11 = 362.729
d11 = D11
r12 = aperture d12 = D12
r13 = 8.369 (aspherical surface)
d13 = 6.65 Nd13 = 1.6935 νd13 = 53.21
r14 = -10.386
d14 = 1 Nd14 = 1.84666 νd14 = 23.78
r15 = 46.150 (aspherical surface)
d15 = D15
r16 = 27.024
d16 = 0.6 Nd16 = 1.48749 νd16 = 70.23
r17 = 10.568
d17 = D17
r18 = 11.900 (aspherical surface)
d18 = 1.8 Nd18 = 1.7432 νd18 = 49.34
r19 = -144.427
d19 = D19
r20 = ∞
d20 = 1.9 Nd20 = 1.54771 νd20 = 62.84
r21 = ∞
d21 = 0.8
r22 = ∞
d22 = 0.75 Nd22 = 1.51633 νd22 = 64.14
r23 = ∞
d23 = D23

Aspherical coefficient fifth surface
k = 0
A4 = 1.82725E-05
A6 = 6.335779E-08
A8 = 0
8th page
k = 0
A4 = 3.26029E-04
A6 = -1.07371E-05
A8 = 1.86563E-07
9th page
k = 0
A4 = -1.18365E-04
A6 = -1.59646E-05
A8 = -3.36469E-07
13th page
k = 0
A4 = 5.45422E-05
A6 = 1.88868E-06
A8 = 1.61743E-08
15th page
k = 0
A4 = 5.07876E-04
A6 = 9.42220E-06
A8 = 4.93661E-07
18th page
k = 0
A4 = -1.01842E-04
A6 = 7.26278E-06
A8 = -1.37874E-07

Zoom data
When D0 (distance from the object to the first surface) is ∞
Wide-angle end Middle Telephoto end
Focal length 6.099 13.418 17.994
FNO. 3.14 4.83 5.85
D7 1.62 7.31 8.54
D11 12.38 3.74 1.14
D12 7.81 3.04 1.17
D15 1.2 11.37 13.91
D17 1.42 1.6 2.93
D19 4.82 1.38 0.4
D23 1.36 1.36 1.36

  FIG. 9 is a cross-sectional view along the optical axis showing the optical configuration when focusing on an object point at infinity at the wide-angle end of a zoom lens according to Example 5 of the present invention.

  FIG. 10 is a diagram illustrating spherical aberration, astigmatism, distortion, and chromatic aberration of magnification when the zoom lens according to Example 5 is focused on an object point at infinity, where (a) is a wide angle end, (b) is an intermediate position, (c) shows the state at the telephoto end.

  As shown in FIG. 9, the zoom lens of Example 5 includes, in order from the object side, a first lens group G1, a second lens group G2, an aperture stop S, a third lens group G3, and a fourth lens group. G4 and the fifth lens group G5 are included. In the figure, LPF is a low-pass filter, CG is a cover glass, and I is an image pickup surface of an electronic image pickup element.

  The first lens group G1 includes a negative meniscus lens L111 having a convex surface facing the object side, a prism L112, and a cemented lens of a negative meniscus lens L113 having a convex surface facing the object side and a biconvex lens L114. It has a refractive power of

  The second lens group G2 includes a biconcave lens L121 and a positive meniscus lens L122 having a convex surface directed toward the positive object side, and has a negative refracting power as a whole.

  The third lens group G3 is composed of a cemented lens made up of a biconvex lens L131 and a biconcave lens L132, and has a positive refractive power as a whole.

  The fourth lens group G4 includes a negative meniscus lens L141 having a convex surface directed toward the object side, and has a negative refracting power as a whole.

  The fifth lens group G5 includes a biconvex lens L142, and has a positive refractive power as a whole.

  When zooming from the wide-angle end to the telephoto end, the first lens group G1 is fixed, the second lens group G2 is moved to the image side, the aperture stop S is fixed, and the third lens group G3 is moved to the object side. The fourth lens group G4 once moves to the image side, then moves to the object side, and moves to the image side of the fifth lens group G5.

  The aspherical surfaces are the object-side surface of the negative meniscus lens L113 with the convex surface facing the object side in the first lens group G1, both surfaces of the biconcave lens L121 in the second lens group G2, and the biconvex lens in the third lens group G3. It is provided on the object side surface of L131, the image side surface of the biconcave lens L132, and the object side surface of the biconvex lens L142 in the fifth lens group G5.

Next, numerical data of this embodiment will be listed.
Numerical data 5
r1 = 27.528
d1 = 1 Nd1 = 1.8061 νd1 = 40.92
r2 = 10.01
d2 = 2.9
r3 = ∞
d3 = 12 Nd3 = 1.8061 νd3 = 40.92
r4 = ∞
d4 = 0.3
r5 = 19.259 (Aspherical surface)
d5 = 0.1 Nd5 = 1.60687 νd5 = 27.03
r6 = 16.049
d6 = 3.54 Nd6 = 1.741 νd6 = 52.64
r7 = -43.585
d7 = D7
r8 = -74.609 (aspherical surface)
d8 = 0.8 Nd8 = 1.8061 νd8 = 40.92
r9 = 5.443 (aspherical surface)
d9 = 0.7
r10 = 7.458
d10 = 2.2 Nd10 = 1.7552 νd10 = 27.51
r11 = 91.204
d11 = D11
r12 = aperture
d12 = D12
r13 = 8.403 (aspherical surface)
d13 = 6.46 Nd13 = 1.6935 νd13 = 53.21
r14 = -10.035
d14 = 1 Nd14 = 1.84666 νd14 = 23.78
r15 = 47.150 (aspherical surface)
d15 = D15
r16 = 24.758
d16 = 0.6 Nd16 = 1.48749 νd16 = 70.23
r17 = 9.504
d17 = D17
r18 = 10.540 (aspherical surface)
d18 = 1.8 Nd18 = 1.7432 νd18 = 49.34
r19 = -222.308
d19 = D19
r20 = ∞
d20 = 1.9 Nd20 = 1.54771 νd20 = 62.84
r21 = ∞
d21 = 0.8
r22 = ∞
d22 = 0.75 Nd22 = 1.51633 νd22 = 64.14
r23 = ∞
d23 = D23

Aspherical coefficient fifth surface
k = 0
A4 = 7.49511E-06
A6 = 6.72180E-08
A8 = 0.000E + 00
8th page
k = 0
A4 = 2.74050E-04
A6 = -1.05373E-05
A8 = 1.91437E-07
9th page
k = 0
A4 = -1.49959E-04
A6 = -1.84286E-05
A8 = -4.07805E-07
13th page
k = 0
A4 = 6.778959E-05
A6 = 2.28068E-06
A8 = -1.02002E-08
15th page
k = 0
A4 = 4.73455E-04
A6 = 1.84961E-05
A8 = -3.16845E-08
18th page
k = 0
A4 = -1.04278E-04
A6 = 9.79328E-06
A8 = -2.57765E-07

Zoom data
When D0 (distance from the object to the first surface) is ∞
Wide-angle end Middle Telephoto end
Focal length 6.002 13.7 17.996
FNO. 2.86 4.73 5.67
D7 0.8 6.8 8.42
D11 9.02 3.01 1.39
D12 10.8 3.53 1.19
D15 1.2 11.73 13.72
D17 1.4 1.59 2.83
D19 4.84 1.4 0.51
D23 1.36 1.36 1.36

  FIG. 11 is a cross-sectional view along the optical axis showing an optical configuration at the time of focusing on an object point at infinity at the wide-angle end of a zoom lens according to Example 6 of the present invention.

  12A and 12B are diagrams showing spherical aberration, astigmatism, distortion, and chromatic aberration of magnification when the zoom lens according to Example 6 is focused on an object point at infinity, where (a) is a wide angle end, (b) is an intermediate position, (c) shows the state at the telephoto end.

  As shown in FIG. 11, the zoom lens of Example 6 includes, in order from the object side, a first lens group G1, a second lens group G2, an aperture stop S, a third lens group G3, and a fourth lens group. G4 and the fifth lens group G5 are included. In the figure, LPF is a low-pass filter, CG is a cover glass, and I is an image pickup surface of an electronic image pickup element.

  The first lens group G1 includes a negative meniscus lens L111 having a convex surface facing the object side, a prism L112, and a cemented lens of a negative meniscus lens L113 having a convex surface facing the object side and a biconvex lens L114. It has a refractive power of

  The second lens group G2 includes a biconcave lens L121 and a positive meniscus lens L122 having a convex surface directed toward the object side, and has a negative refracting power as a whole.

  The third lens group G3 is composed of a cemented lens made up of a biconvex lens L131 and a biconcave lens L132, and has a positive refractive power as a whole.

  The fourth lens group G4 includes a negative meniscus lens L141 having a convex surface directed toward the object side, and has a negative refracting power as a whole.

  The fifth lens group G5 includes a biconvex lens L142, and has a positive refractive power as a whole.

  When zooming from the wide-angle end to the telephoto end, the first lens group G1 is fixed, the second lens group G2 is moved to the image side, the aperture stop S is fixed, and the third lens group G3 is moved to the object side. The fourth lens group G4 once moves to the image side, then moves to the object side, and moves to the image side of the fifth lens group G5.

  The aspherical surfaces are the object-side surface of the negative meniscus lens L113 with the convex surface facing the object side in the first lens group G1, both surfaces of the biconcave lens L121 in the second lens group G2, and the biconvex lens in the third lens group G3. It is provided on the object side surface of L131, the image side surface of the biconcave lens L132, and the object side surface of the biconvex lens L142 in the fifth lens group G5.

Next, numerical data of this embodiment will be listed.
Numerical data 6
r1 = 28.438
d1 = 1 Nd1 = 1.8061 νd1 = 40.92
r2 = 10.004
d2 = 2.9
r3 = ∞
d3 = 12 Nd3 = 1.8061 νd3 = 40.92
r4 = ∞
d4 = 0.3
r5 = 20.895 (aspherical surface)
d5 = 0.1 Nd5 = 1.60258 νd5 = 18.58
r6 = 17.413
d6 = 3.06 Nd6 = 1.741 νd6 = 52.64
r7 = -37.246
d7 = D7
r8 = -78.978 (aspherical surface)
d8 = 0.73 Nd8 = 1.8061 νd8 = 40.92
r9 = 5.188 (aspherical surface)
d9 = 0.64
r10 = 7.149
d10 = 1.47 Nd10 = 1.7552 νd10 = 27.51
r11 = 121.309
d11 = D11
r12 = aperture d12 = D12
r13 = 8.146 (aspherical surface)
d13 = 7.35 Nd13 = 1.6935 νd13 = 53.21
r14 = -8.498
d14 = 1 Nd14 = 1.84666 νd14 = 23.78
r15 = 50.867 (aspherical surface)
d15 = D15
r16 = 38.968
d16 = 0.6 Nd16 = 1.48749 νd16 = 70.23
r17 = 9.515
d17 = D17
r18 = 9.852 (aspherical surface)
d18 = 1.8 Nd18 = 1.7432 νd18 = 49.34
r19 = -328.893
d19 = D19
r20 = ∞
d20 = 1.9 Nd20 = 1.54771 νd20 = 62.84
r21 = ∞
d21 = 0.8
r22 = ∞
d22 = 0.75 Nd22 = 1.51633 νd22 = 64.14
r23 = ∞
d23 = D23

Aspherical coefficient fifth surface
k = 0
A4 = 1.23119E-05
A6 = 8.84042E-08
A8 = 0
8th page
k = 0
A4 = 8.85570E-05
A6 = -5.07500E-07
A8 = -1.21145E-07
9th page
k = 0
A4 = -5.11299E-04
A6 = 8.61810E-06
A8 = -1.99402E-06
13th page
k = 0
A4 = -4.74670E-06
A6 = 4.46373E-06
A8 = -8.38829E-08
15th page
k = 0
A4 = 5.04643E-04
A6 = 8.30882E-06
A8 = 6.17273E-07
18th page
k = 0
A4 = -8.08479E-05
A6 = 1.950506E-06
A8 = -1.12576E-08

Zoom data
When D0 (distance from the object to the first surface) is ∞
Wide-angle end Middle Telephoto end
Focal length 6 13.7 17.999
FNO. 2.86 3.93 5.06
D7 0.8 10.24 10.6
D11 11.2 1.76 1.4
D12 8.75 4.27 1.2
D15 1.2 7.9 10.53
D17 1.28 1.42 3.34
D19 4.33 1.98 0.5
D23 1.36 1.36 1.36

  FIG. 13 is a cross-sectional view along the optical axis showing an optical configuration at the time of focusing on an object point at infinity at the wide-angle end of a zoom lens according to Example 7 of the present invention.

  FIG. 14 is a diagram showing spherical aberration, astigmatism, distortion aberration, and chromatic aberration of magnification when the zoom lens according to Example 7 is focused on an object point at infinity, where (a) is a wide angle end, (b) is an intermediate position, (c) shows the state at the telephoto end.

  As shown in FIG. 13, the zoom lens according to the seventh exemplary embodiment includes, in order from the object side, the first lens group G1, the second lens group G2, the aperture stop S, the third lens group G3, and the fourth lens group. G4 and the fifth lens group G5 are included. In the figure, LPF is a low-pass filter, CG is a cover glass, and I is an image pickup surface of an electronic image pickup element.

  The first lens group G1 includes a negative meniscus lens L111 having a convex surface facing the object side, a prism L112, and a cemented lens of a negative meniscus lens L113 having a convex surface facing the object side and a biconvex lens L114. It has a refractive power of

  The second lens group G2 includes a biconcave lens L121 and a positive meniscus lens L122 having a convex surface directed toward the object side, and has a negative refracting power as a whole.

  The third lens group G3 is composed of a cemented lens made up of a biconvex lens L131 and a biconcave lens L132, and has a positive refractive power as a whole.

  The fourth lens group G4 includes a negative meniscus lens L141 having a convex surface directed toward the object side, and has a negative refracting power as a whole.

  The fifth lens group G5 includes a biconvex lens L142, and has a positive refractive power as a whole.

  When zooming from the wide-angle end to the telephoto end, the first lens group G1 is fixed, the second lens group G2 is moved to the image side, the aperture stop S is fixed, and the third lens group G3 is moved to the object side. The fourth lens group G4 once moves to the image side, then moves to the object side, and moves to the image side of the fifth lens group G5.

  The aspherical surfaces are the object-side surface of the negative meniscus lens L113 with the convex surface facing the object side in the first lens group G1, both surfaces of the biconcave lens L121 in the second lens group G2, and the biconvex lens in the third lens group G3. It is provided on the object side surface of L131, the image side surface of the biconcave lens L132, and the object side surface of the biconvex lens L142 in the fifth lens group G5.

Next, numerical data of this embodiment will be listed.
Numerical data 7
r1 = 27.426
d1 = 1 Nd1 = 1.8061 νd1 = 40.92
r2 = 10.031
d2 = 2.9
r3 = ∞
d3 = 12 Nd3 = 1.8061 νd3 = 40.92
r4 = ∞
d4 = 0.3
r5 = 19.203 (Aspherical surface)
d5 = 0.1 Nd5 = 1.69556 νd5 = 25.02.
r6 = 16.038
d6 = 3.54 Nd6 = 1.741 νd6 = 52.64
r7 = -43.264
d7 = D7
r8 = -75.475 (Aspherical surface)
d8 = 0.8 Nd8 = 1.8061 νd8 = 40.92
r9 = 5.450 (aspherical surface)
d9 = 0.7
r10 = 7.448
d10 = 2.2 Nd10 = 1.7552 νd10 = 27.51
r11 = 92.147
d11 = D11
r12 = aperture
d12 = D12
r13 = 8.392 (aspherical surface)
d13 = 6.46 Nd13 = 1.6935 νd13 = 53.21
r14 = -10.047
d14 = 1 Nd14 = 1.84666 νd14 = 23.78
r15 = 47.431 (Aspherical surface)
d15 = D15
r16 = 24.831
d16 = 0.6 Nd16 = 1.48749 νd16 = 70.23
r17 = 9.493
d17 = D17
r18 = 10.557 (aspherical surface)
d18 = 1.8 Nd18 = 1.7432 νd18 = 49.34
r19 = -230.141
d19 = D19
r20 = ∞
d20 = 1.9 Nd20 = 1.54771 νd20 = 62.84
r21 = ∞
d21 = 0.8
r22 = ∞
d22 = 0.75 Nd22 = 1.51633 νd22 = 64.14
r23 = ∞
d23 = D23

Aspherical coefficient fifth surface
k = 0
A4 = 1.12705E-05
A6 = -8.08778E-08
A8 = 0
7th page
k = 0
A4 = 2.73216E-04
A6 = -1.02234E-05
A8 = 1.64643E-07
k = 0
9th page
k = 0
A4 = -1.46628E-04
A6 = -1.85741E-05
A8 = -4.55787E-07
13th page
k = 0
A4 = 6.74961E-05
A6 = 2.14113E-06
A8 = -1.38046E-08
15th page
A4 = 4.72765E-04
A6 = 1.81729E-05
A8 = -5.79597E-08
18th page
k = 0
A4 = -1.04231E-04
A6 = 9.85834E-06
A8 = -2.64507E-07

Zoom data
When D0 (distance from the object to the first surface) is ∞
Wide-angle end Middle Telephoto end
Focal length 6.005 13.639 17.893
FNO. 2.86 4.73 5.67
D7 0.8 6.8 8.42
D11 9.02 3.01 1.39
D12 10.8 3.53 1.19
D15 1.2 11.73 13.72
D17 1.4 1.59 2.83
D19 4.84 1.4 0.51
D23 1.35 1.36 1.4

  FIG. 15 is a cross-sectional view along the optical axis showing an optical configuration at the time of focusing on an object point at infinity at the wide-angle end of a zoom lens according to Example 8 of the present invention.

  FIG. 16 is a diagram showing spherical aberration, astigmatism, distortion, and chromatic aberration of magnification when the zoom lens according to Example 8 is focused on an object point at infinity, where (a) is the wide-angle end, (b) is the middle, (c) shows the state at the telephoto end.

  As shown in FIG. 15, the zoom lens of Example 8 includes, in order from the object side, the first lens group G1, the second lens group G2, the aperture stop S, the third lens group G3, and the fourth lens group. G4 and the fifth lens group G5 are included. In the figure, LPF is a low-pass filter, CG is a cover glass, and I is an image pickup surface of an electronic image pickup element.

  The first lens group G1 includes a negative meniscus lens L111 having a convex surface facing the object side, a prism L112, and a cemented lens of a negative meniscus lens L113 having a convex surface facing the object side and a biconvex lens L114. It has a refractive power of

  The second lens group G2 includes a biconcave lens L121 and a positive meniscus lens L122 having a convex surface directed toward the object side, and has a negative refracting power as a whole.

  The third lens group G3 is composed of a cemented lens made up of a biconvex lens L131 and a biconcave lens L132, and has a positive refractive power as a whole.

  The fourth lens group G4 includes a negative meniscus lens L141 having a convex surface directed toward the object side, and has a negative refracting power as a whole.

  The fifth lens group G5 includes a biconvex lens L142, and has a positive refractive power as a whole.

  When zooming from the wide-angle end to the telephoto end, the first lens group G1 is fixed, the second lens group G2 is moved to the image side, the aperture stop S is fixed, and the third lens group G3 is moved to the object side. The fourth lens group G4 once moves to the image side, then moves to the object side, and moves to the image side of the fifth lens group G5.

  The aspherical surfaces are the object-side surface of the negative meniscus lens L113 with the convex surface facing the object side in the first lens group G1, both surfaces of the biconcave lens L121 in the second lens group G2, and the biconvex lens in the third lens group G3. It is provided on the object side surface of L131, the image side surface of the biconcave lens L132, and the object side surface of the biconvex lens L142 in the fifth lens group G5.

Next, numerical data of this embodiment will be listed.
Numerical data 8
r1 = 28.32
d1 = 1 Nd1 = 1.8061 νd1 = 40.92
r2 = 10.005
d2 = 2.9
r3 = ∞
d3 = 12 Nd3 = 1.8061 νd3 = 40.92
r4 = ∞
d4 = 0.3
r5 = 20.841 (Aspherical surface)
d5 = 0.1 Nd5 = 1.72568 νd5 = 18.68
r6 = 17.368
d6 = 2.82 Nd6 = 1.741 νd6 = 52.64
r7 = -35.523
d7 = D7
r8 = -77.234 (Aspherical surface)
d8 = 0.61 Nd8 = 1.8061 νd8 = 40.92
r9 = 5.150 (Aspherical surface)
d9 = 0.64
r10 = 7.099
d10 = 1.79 Nd10 = 1.7552 νd10 = 27.51
r11 = 125.495
d11 = D11
r12 = aperture d12 = D12
r13 = 8.137 (aspherical surface)
d13 = 7.8 Nd13 = 1.6935 νd13 = 53.21
r14 = -8.325
d14 = 1 Nd14 = 1.84666 νd14 = 23.78
r15 = 50.362 (Aspherical surface)
d15 = D15
r16 = 40.192
d16 = 0.6 Nd16 = 1.48749 νd16 = 70.23
r17 = 9.772
d17 = D17
r18 = 9.992 (Aspherical surface)
d18 = 1.8 Nd18 = 1.7432 νd18 = 49.34
r19 = -337.631
d19 = D19
r20 = ∞
d20 = 1.9 Nd20 = 1.54771 νd20 = 62.84
r21 = ∞
d21 = 0.8
r22 = ∞
d22 = 0.75 Nd22 = 1.51633 νd22 = 64.14
r23 = ∞
d23 = D23

Aspherical coefficient fifth surface
k = 0
A4 = 1.00332E-05
A6 = 7.42109E-08
A8 = 0
8th page
k = 0
A4 = 1.02571E-04
A6 = -5.01039E-06
A8 = -2.49531E-09
9th page
k = 0
A4 = -4.89182E-04
A6 = -1.89829E-07
A8 = -1.78387E-06
13th page
k = 0
A4 = -2.76088E-06
A6 = 2.53907E-06
A8 = -5.24977E-08
15th page
k = 0
A4 = 5.14295E-04
A6 = 1.03006E-05
A8 = 4.35904E-07
18th page
k = 0
A4 = -8.37722E-05
A6 = 3.59740E-06
A8 = -5.85328E-08

Zoom data
When D0 (distance from the object to the first surface) is ∞
Wide-angle end Middle Telephoto end
Focal length 6.005 13.7 17.999
FNO. 2.86 3.83 4.95
D7 0.8 10.69 10.96
D11 11.56 1.68 1.4
D12 8.42 4.29 1.2
D15 1.2 7.13 9.86
D17 1.31 1.55 3.48
D19 4.11 2.05 0.5
D23 1.36 1.36 1.36

  FIG. 17 is a cross-sectional view along the optical axis showing an optical configuration at the time of focusing on an object point at infinity at the wide-angle end of a zoom lens according to Example 9 of the present invention.

  FIG. 18 is a diagram illustrating spherical aberration, astigmatism, distortion, and lateral chromatic aberration when the zoom lens according to Example 9 is focused on an object point at infinity, where (a) is a wide-angle end, (b) is an intermediate view, (c) shows the state at the telephoto end.

  As shown in FIG. 17, the zoom lens according to the ninth embodiment includes, in order from the object side, the first lens group G1, the second lens group G2, the aperture stop S, the third lens group G3, and the fourth lens group. G4 and the fifth lens group G5 are included. In the figure, LPF is a low-pass filter, CG is a cover glass, and I is an image pickup surface of an electronic image pickup element.

  The first lens group G1 includes a negative meniscus lens L111 having a convex surface facing the object side, a prism L112, and a cemented lens of a negative meniscus lens L113 having a convex surface facing the object side and a biconvex lens L114. It has a refractive power of

  The second lens group G2 includes a biconcave lens L121 and a positive meniscus lens L122 having a convex surface directed toward the object side, and has a negative refracting power as a whole.

  The third lens group G3 is composed of a cemented lens made up of a biconvex lens L131 and a biconcave lens L132, and has a positive refractive power as a whole.

  The fourth lens group G4 includes a negative meniscus lens L141 having a convex surface directed toward the object side, and has a negative refracting power as a whole.

  The fifth lens group G5 includes a biconvex lens L142, and has a positive refractive power as a whole.

  When zooming from the wide-angle end to the telephoto end, the first lens group G1 is fixed, the second lens group G2 is moved to the image side, the aperture stop S is fixed, and the third lens group G3 is moved to the object side. The fourth lens group G4 once moves to the image side, then moves to the object side, and moves to the image side of the fifth lens group G5.

  The aspherical surfaces are the object-side surface of the negative meniscus lens L113 with the convex surface facing the object side in the first lens group G1, both surfaces of the biconcave lens L121 in the second lens group G2, and the biconvex lens in the third lens group G3. It is provided on the object side surface of L131, the image side surface of the biconcave lens L132, and the object side surface of the biconvex lens L142 in the fifth lens group G5.

Next, numerical data of this embodiment will be listed.
Numerical data 9
r1 = 28.32
d1 = 1 Nd1 = 1.8061 νd1 = 40.92
r2 = 10.005
d2 = 2.9
r3 = ∞
d3 = 12 Nd3 = 1.8061 νd3 = 40.92
r4 = ∞
d4 = 0.3
r5 = 20.841 (Aspherical surface)
d5 = 0.1 Nd5 = 1.72568 νd5 = 18.68
r6 = 17.368
d6 = 2.82 Nd6 = 1.741 νd6 = 52.64
r7 = -35.523
d7 = D7
r8 = -77.234 (Aspherical surface)
d8 = 0.61 Nd8 = 1.8061 νd8 = 40.92
r9 = 5.150 (aspherical surface)
d9 = 0.64
r10 = 7.099
d10 = 1.79 Nd10 = 1.7552 νd10 = 27.51
r11 = 125.495
d11 = D11
r12 = aperture d12 = D12
r13 = 8.137 (aspherical surface)
d13 = 7.8 Nd13 = 1.6935 νd13 = 53.21
r14 = -8.325
d14 = 1 Nd14 = 1.84666 νd14 = 23.78
r15 = 50.362 (Aspherical surface)
d15 = D15
r16 = 40.192
d16 = 0.6 Nd16 = 1.48749 νd16 = 70.23
r17 = 9.772
d17 = D17
r18 = 9.992 (Aspherical surface)
d18 = 1.8 Nd18 = 1.7432 νd18 = 49.34
r19 = -337.631
d19 = D19
r20 = ∞
d20 = 1.9 Nd20 = 1.54771 νd20 = 62.84
r21 = ∞
d21 = 0.8
r22 = ∞
d22 = 0.75 Nd22 = 1.51633 νd22 = 64.14
r23 = ∞
d23 = D23

Aspherical coefficient fifth surface
k = 0
A4 = 1.00332E-05
A6 = 7.42109E-08
A8 = 0
8th page
k = 0
A4 = 1.02571E-04
A6 = -5.01039E-06
A8 = -2.49531E-09
9th page
k = 0
A4 = -4.89182E-04
A6 = -1.89829E-07
A8 = -1.78387E-06
13th page
k = 0
A4 = -2.76088E-06
A6 = 2.53907E-06
A8 = -5.24977E-08
15th page
k = 0
A4 = 5.14295E-04
A6 = 1.03006E-05
A8 = 4.35904E-07
18th page
k = 0
A4 = -8.37722E-05
A6 = 3.59740E-06
A8 = -5.85328E-08

Zoom data
When D0 (distance from the object to the first surface) is ∞
Wide-angle end Middle Telephoto end
Focal length 6.005 13.7 17.999
FNO. 2.86 3.83 4.95
D7 0.8 10.69 10.96
D11 11.56 1.68 1.4
D12 8.42 4.29 1.2
D15 1.2 7.13 9.86
D17 1.31 1.55 3.48
D19 4.11 2.05 0.5
D23 1.36 1.36 1.36

  FIG. 19 is a cross-sectional view along the optical axis showing an optical configuration at the time of focusing on an object point at infinity at the wide-angle end of the zoom lens according to Example 10 of the present invention.

  FIG. 20 is a diagram illustrating spherical aberration, astigmatism, distortion, and chromatic aberration of magnification when the zoom lens according to Example 10 is focused on an object point at infinity, where (a) is a wide-angle end, (b) is an intermediate position, (c) shows the state at the telephoto end.

  As shown in FIG. 19, the zoom lens according to the tenth embodiment includes, in order from the object side, the first lens group G1, the second lens group G2, the aperture stop S, the third lens group G3, and the fourth lens group. G4. In the figure, LPF is a low-pass filter, CG is a cover glass, and I is an image pickup surface of an electronic image pickup element.

  The first lens group G1 includes a negative meniscus lens L211 having a convex surface directed toward the object side, a prism L212, and a cemented lens of a biconvex lens L213 and a biconcave lens L214, and has a negative refracting power as a whole. .

  The second lens group G2 includes a cemented lens which is formed by a biconvex lens L221 and a negative meniscus lens L222 having a convex surface directed toward the image side, and has a positive refractive power as a whole.

  The third lens group G3 includes a cemented lens which is formed by a biconcave lens L231 and a positive meniscus lens L232 having a convex surface directed toward the object side, and has a negative refracting power as a whole.

  The fourth lens group G4 includes a cemented lens which is formed by a biconvex lens L241 and a negative meniscus lens L242 having a concave surface directed toward the object side, and has a positive refracting power as a whole.

  When zooming from the wide-angle end to the telephoto end, the first lens group G1 is fixed, the second lens group G2 is moved to the object side, the aperture stop S is fixed, and the third lens group G3 is moved to the image side. Then, the fourth lens group G4 moves to the image side.

  The aspherical surface is the object side surface of the biconvex lens L213 in the first lens group G1, the object side surface of the biconvex lens L221 in the second lens group G2, and the image side of the negative meniscus lens L222 with the convex surface facing the image side. On the object side surface of the biconvex lens L241 in the fourth lens group G4.

Next, numerical data of this embodiment will be listed.
Numerical data 10
r1 = 31.119
d1 = 1.1 Nd1 = 1.7432 νd1 = 49.34
r2 = 9.391
d2 = 3
r3 = ∞
d3 = 12.5 Nd3 = 1.801 νd3 = 34.97
r4 = ∞
d4 = 0.4
r5 = 65.828 (Aspherical surface)
d5 = 2.4 Nd5 = 1.788 νd5 = 47.37
r6 = -10.213
d6 = 0.71 Nd6 = 1.54814 νd6 = 45.79
r7 = 18.7
d7 = D7
r8 = 13.007 (Aspherical surface)
d8 = 4 Nd8 = 1.48749 νd8 = 70.23
r9 = -11.25
d9 = 0.35 Nd9 = 1.41003 νd9 = 43.2
r10 = -42.837 (Aspherical surface)
d10 = D10
r11 = aperture
d11 = D11
r12 = -14.807
d12 = 0.7 Nd12 = 1.48749 νd12 = 70.23
r13 = 8.248
d13 = 1.6 Nd13 = 1.83481 νd13 = 42.71
r14 = 16.867
d14 = D14
r15 = 11.881 (aspherical surface)
d15 = 3.5 Nd15 = 1.7432 νd15 = 49.34
r16 = -6
d16 = 0.7 Nd16 = 1.84666 νd16 = 23.78
r17 = -16.949
d17 = D17
r18 = ∞
d18 = 1.44 Nd18 = 1.54771 νd18 = 62.84
r19 = ∞
d19 = 0.8
r20 = ∞
d20 = 0.6 Nd20 = 1.51633 νd20 = 64.14
r21 = ∞
d21 = D21

Aspherical coefficient fifth surface
k = 0
A4 = 1.81628E-05
A6 = -3.43707E-07
A8 = 0.000E + 00
8th page
k = 0
A4 = -1.02619E-04
A6 = -2.37761E-07
A8 = -4.21441E-07
10th page
k = 0
A4 = -1.62287E-05
A6 = -2.68120E-07
A8 = -1.28129E-06
15th page
k = 0
A4 = -1.72009E-04
A6 = 9.22144E-07
A8 = 5.27383E-08

Zoom data
When D0 (distance from the object to the first surface) is ∞

Wide-angle end Middle Telephoto end
Focal length 5.994 13.684 17.99
FNO. 2.85 3.55 3.78
D7 15.33 4.79 0.8
D10 1.6 12.14 16.13
D11 1.4 7.71 9.54
D14 6.51 3.84 3
D17 5.84 2.21 1.21
D21 1.36 1.36 1.31

  FIG. 21 is a cross-sectional view along the optical axis showing an optical configuration at the time of focusing on an object point at infinity at the wide-angle end of a zoom lens according to Example 11 of the present invention.

  FIG. 22 is a diagram illustrating spherical aberration, astigmatism, distortion, and lateral chromatic aberration when the zoom lens according to Example 11 is focused on an object point at infinity, where (a) is a wide angle end, (b) is an intermediate position, (c) shows the state at the telephoto end.

  As shown in FIG. 21, the zoom lens of Example 11 includes, in order from the object side, a first lens group G1, a second lens group G2, an aperture stop S, a third lens group G3, and a fourth lens group. G4. In the figure, LPF is a low-pass filter, CG is a cover glass, and I is an image pickup surface of an electronic image pickup element.

  The first lens group G1 includes a negative meniscus lens L211 having a convex surface directed toward the object side, a prism L212, and a cemented lens of a biconvex lens L213 and a biconcave lens L214, and has a negative refracting power as a whole. .

  The second lens group G2 includes a cemented lens which is formed by a biconvex lens L221 and a negative meniscus lens L222 having a convex surface directed toward the image side, and has a positive refractive power as a whole.

  The third lens group G3 includes a cemented lens which is formed by a biconcave lens L231 and a positive meniscus lens L232 having a convex surface directed toward the object side, and has a negative refracting power as a whole.

  The fourth lens group G4 includes a cemented lens which is formed by a biconvex lens L241 and a negative meniscus lens L242 having a concave surface directed toward the object side, and has a positive refracting power as a whole.

  When zooming from the wide-angle end to the telephoto end, the first lens group G1 is fixed, the second lens group G2 is moved to the object side, the aperture stop S is fixed, and the third lens group G3 is moved to the image side. Then, the fourth lens group G4 moves to the image side.

  The aspherical surface is the object side surface of the biconvex lens L213 in the first lens group G1, the object side surface of the biconvex lens L221 in the second lens group G2, and the image side of the negative meniscus lens L222 with the convex surface facing the image side. On the object side surface of the biconvex lens L241 in the fourth lens group G4.

Next, numerical data of this embodiment will be listed.
Numerical data 11
r1 = 29.72
d1 = 1.1 Nd1 = 1.7432 νd1 = 49.34
r2 = 9.703
d2 = 3
r3 = ∞
d3 = 12.5 Nd3 = 1.74816 νd3 = 52.18
r4 = ∞
d4 = 0.4
r5 = 57.487 (aspherical surface)
d5 = 2.2 Nd5 = 1.8003 νd5 = 46.65
r6 = -18.728
d6 = 0.7 Nd6 = 1.53347 νd6 = 56.28
r7 = 14.529
d7 = D7
r8 = 11.032 (aspherical surface)
d8 = 4 Nd8 = 1.5 νd8 = 82
r9 = -12
d9 = 0.35 Nd9 = 1.51556 νd9 = 37.55
r10 = -24.260 (Aspherical surface)
d10 = D10
r11 = aperture d11 = D11
r12 = -23.447
d12 = 0.7 Nd12 = 1.52581 νd12 = 60.4
r13 = 6.738
d13 = 1.6 Nd13 = 1.843481 νd13 = 43.89
r14 = 14.631
d14 = D14
r15 = 12.318 (aspherical surface)
d15 = 3.5 Nd15 = 1.74388 νd15 = 52.73
r16 = -6
d16 = 0.7 Nd16 = 1.81491 νd16 = 26.14
r17 = -29.392
d17 = D17
r18 = ∞
d18 = 1.44 Nd18 = 1.54771 νd18 = 62.84
r19 = ∞
d19 = 0.8
r20 = ∞
d20 = 0.6 Nd20 = 1.51633 νd20 = 64.14
r21 = ∞
d21 = D21

Aspherical coefficient fifth surface
k = 0
A4 = 5.26307E-05
A6 = 4.03808E-07
A8 = 0
8th page
k = 0
A4 = -7.30022E-05
A6 = -5.57235E-08
A8 = 0.000E + 00
10th page
k = 0
A4 = 6.40252E-05
A6 = 6.31247E-07
A8 = 0.000E + 00
15th page
k = 0
A4 = -1.88431E-04
A6 = 7.90555E-07
A8 = 0.000E + 00

Zoom data
When D0 (distance from the object to the first surface) is ∞
Wide-angle end Middle Telephoto end
Focal length 6.1 13.42 17.996
FNO. 3.2 3.63 4.4
D7 16.78 3.04 1.06
D10 2.56 11.53 13.78
D11 1.04 6.15 12.19
D14 6.22 2.98 2.1
D17 4.71 3.69 1.79
D21 1.36 1.36 1.36

  FIG. 23 is a cross-sectional view along the optical axis showing an optical configuration at the time of focusing on an object point at infinity at the wide-angle end of a zoom lens according to Example 12 of the present invention.

  FIG. 24 is a diagram illustrating spherical aberration, astigmatism, distortion, and chromatic aberration of magnification when the zoom lens according to Example 12 is focused on an object point at infinity, where (a) is a wide angle end, (b) is an intermediate view, (c) shows the state at the telephoto end.

  As shown in FIG. 23, in the zoom lens of Example 12, the first lens group G1, the second lens group G2, the aperture stop S, the third lens group G3, and the fourth lens group are sequentially arranged from the object side. G4. In the figure, LPF is a low-pass filter, CG is a cover glass, and I is an image pickup surface of an electronic image pickup element.

  The first lens group G1 includes a negative meniscus lens L211 having a convex surface directed toward the object side, a prism L212, and a cemented lens of a positive meniscus lens L213 having a convex surface directed toward the image side and a biconcave lens L214. It has a refractive power of

  The second lens group G2 includes a cemented lens which is formed by a biconvex lens L221 and a negative meniscus lens L222 having a convex surface directed toward the image side, and has a positive refractive power as a whole.

  The third lens group G3 includes a cemented lens which is formed by a biconcave lens L231 and a positive meniscus lens L232 having a convex surface directed toward the object side, and has a negative refracting power as a whole.

  The fourth lens group G4 includes a cemented lens which is formed by a biconvex lens L241 and a negative meniscus lens L242 having a concave surface directed toward the object side, and has a positive refracting power as a whole.

  When zooming from the wide-angle end to the telephoto end, the first lens group G1 is fixed, the second lens group G2 is moved to the object side, the aperture stop S is fixed, and the third lens group G3 is moved to the image side. Then, the fourth lens group G4 moves to the image side.

  The aspherical surface has the object side surface of the positive meniscus lens L213 having a convex surface facing the image side in the first lens group G1, the object side surface of the biconvex lens L221 in the second lens group G2, and the convex surface facing the image side. The negative meniscus lens L222 is provided on the image side surface, and on the object side surface of the biconvex lens L241 in the fourth lens group G4.

Next, numerical data of this embodiment will be listed.
Numerical data 12
r1 = 20.158
d1 = 1.1 Nd1 = 1.7432 νd1 = 49.34
r2 = 7.906
d2 = 3
r3 = ∞
d3 = 9.15 Nd3 = 1.801 νd3 = 34.97
r4 = ∞
d4 = 0.43
r5 = -521.675 (aspherical surface)
d5 = 2.59 Nd5 = 1.8061 νd5 = 40.92
r6 = -12.899
d6 = 3.06 Nd6 = 1.51823 νd6 = 58.9
r7 = 20.031
d7 = D7
r8 = 13.946 (aspherical surface)
d8 = 9.88 Nd8 = 1.50032 νd8 = 81.92
r9 = -12
d9 = 0.35 Nd9 = 1.41144 νd9 = 16.88
r10 = -16.207 (aspherical surface)
d10 = D10
r11 = aperture d11 = D11
r12 = -21.27
d12 = 0.9 Nd12 = 1.51436 νd12 = 68.14
r13 = 7.13
d13 = 1.73 Nd13 = 1.82329 νd13 = 44.75
r14 = 18.361
d14 = D14
r15 = 24.502 (aspherical surface)
d15 = 3.93 Nd15 = 1.7432 νd15 = 49.34
r16 = -6
d16 = 3.26 Nd16 = 1.84666 νd16 = 23.78
r17 = -14.372
d17 = D17
r18 = ∞
d18 = 1.44 Nd18 = 1.54771 νd18 = 62.84
r19 = ∞
d19 = 0.8
r20 = ∞
d20 = 0.6 Nd20 = 1.51633 νd20 = 64.14
r21 = ∞
d21 = D21

Aspherical coefficient fifth surface
k = 0
A4 = 4.27494E-05
A6 = 1.13768E-06
A8 = 0
8th page
k = 0
A4 = -7.86847E-05
A6 = -1.62983E-06
A8 = 0.000E + 00
10th page
k = 0
A4 = 3.48431E-05
A6 = -6.61795E-07
A8 = 0.000E + 00
15th page
k = 0
A4 = -2.32969E-04
A6 = 4.59145E-07
A8 = 0.000E + 00

Zoom data
When D0 (distance from the object to the first surface) is ∞
Wide-angle end Middle Telephoto end
Focal length 6.1 13.42 17.996
FNO. 3.15 3.78 4.58
D7 15.4 2.87 0.52
D10 1.75 10 12
D11 0.65 6.27 10.58
D14 3.36 2.5 2.56
D17 4.74 2.21 0.4
D21 1.36 1.36 1.36

  FIG. 25 is a cross-sectional view along the optical axis showing an optical configuration at the time of focusing on an object point at infinity at the wide-angle end of a zoom lens according to Example 13 of the present invention.

  FIG. 26 is a diagram illustrating spherical aberration, astigmatism, distortion, and chromatic aberration of magnification when the zoom lens according to Example 13 is focused on an object point at infinity, in which (a) is a wide angle end, (b) is an intermediate position, (c) shows the state at the telephoto end.

  As shown in FIG. 25, the zoom lens of Example 13 includes, in order from the object side, the first lens group G1, the second lens group G2, the aperture stop S, the third lens group G3, and the fourth lens group. G4. In the figure, LPF is a low-pass filter, CG is a cover glass, and I is an image pickup surface of an electronic image pickup element.

  The first lens group G1 includes a negative meniscus lens L211 having a convex surface directed toward the object side, a prism L212, and a cemented lens of a biconvex lens L213 and a biconcave lens L214, and has a negative refracting power as a whole. .

  The second lens group G2 includes a cemented lens which is formed by a biconvex lens L221 and a negative meniscus lens L222 having a convex surface directed toward the image side, and has a positive refractive power as a whole.

  The third lens group G3 includes a cemented lens which is formed by a biconcave lens L231 and a positive meniscus lens L232 having a convex surface directed toward the object side, and has a negative refracting power as a whole.

  The fourth lens group G4 includes a cemented lens which is formed by a biconvex lens L241 and a negative meniscus lens L242 having a concave surface directed toward the object side, and has a positive refracting power as a whole.

  When zooming from the wide-angle end to the telephoto end, the first lens group G1 is fixed, the second lens group G2 is moved to the object side, the aperture stop S is fixed, and the third lens group G3 is moved to the image side. Then, the fourth lens group G4 moves to the image side.

  The aspherical surface is the object side surface of the biconvex lens L213 in the first lens group G1, the object side surface of the biconvex lens L221 in the second lens group G2, and the image side of the negative meniscus lens L222 with the convex surface facing the image side. On the object side surface of the biconvex lens L241 in the fourth lens group G4.

Next, numerical data of this embodiment will be listed.
Numerical data 13
r1 = 23.804
d1 = 1.1 Nd1 = 1.7432 νd1 = 49.34
r2 = 8.973
d2 = 3
r3 = ∞
d3 = 12.5 Nd3 = 1.773732 νd3 = 48.84
r4 = ∞
d4 = 0.4
r5 = 81.707 (aspherical surface)
d5 = 2.2 Nd5 = 1.80217 νd5 = 39.65
r6 = -16.982
d6 = 0.7 Nd6 = 1.53279 νd6 = 67.15
r7 = 15.738
d7 = D7
r8 = 12.324 (aspherical surface)
d8 = 4 Nd8 = 1.50148 νd8 = 80.28
r9 = -12
d9 = 0.35 Nd9 = 1.5511 νd9 = 20.02
r10 = -19.605 (Aspherical surface)
d10 = D10
r11 = aperture d11 = D11
r12 = -21.295
d12 = 0.7 Nd12 = 1.52576 νd12 = 60.43
r13 = 6.936
d13 = 1.6 Nd13 = 1.83599 νd13 = 43.8
r14 = 16.267
d14 = D14
r15 = 12.685 (Aspherical surface)
d15 = 3.5 Nd15 = 1.74405 νd15 = 52.71
r16 = -6
d16 = 0.7 Nd16 = 1.81473 νd16 = 29.34
r17 = -29.745
d17 = D17
r18 = ∞
d18 = 1.44 Nd18 = 1.54771 νd18 = 62.84
r19 = ∞
d19 = 0.8
r20 = ∞
d20 = 0.6 Nd20 = 1.51633 νd20 = 64.14
r21 = ∞
d21 = D21

Aspherical coefficient fifth surface
k = 0
A4 = 5.39201E-05
A6 = 4.37740E-07
A8 = 0
8th page
k = 0
A4 = -7.41595E-05
A6 = -8.93707E-07
A8 = 0.000E + 00
10th page
k = 0
A4 = 3.40872E-05
A6 = -2.92594E-07
A8 = 0.000E + 00
15th page
k = 0
A4 = -1.88834E-04
A6 = 1.43390E-06
A8 = 0.000E + 00

Zoom data
When D0 (distance from the object to the first surface) is ∞
Wide-angle end Middle Telephoto end
Focal length 6.1 13.42 17.995
FNO. 3.22 3.71 4.46
D7 17.34 3.09 1.02
D10 2.8 11.34 13.72
D11 1.31 6.14 12.53
D14 5.88 3.68 2.15
D17 4.62 3.82 1.8
D21 1.36 1.36 1.36

  FIG. 27 is a cross-sectional view along the optical axis showing an optical configuration at the time of focusing on an object point at infinity at the wide-angle end of a zoom lens according to Example 14 of the present invention.

  FIG. 28 is a diagram showing spherical aberration, astigmatism, distortion, and lateral chromatic aberration when the zoom lens according to Example 14 is focused on an object point at infinity, where (a) is a wide angle end, (b) is an intermediate view, (c) shows the state at the telephoto end.

  As shown in FIG. 27, the zoom lens of Example 14 includes, in order from the object side, the first lens group G1, the second lens group G2, the aperture stop S, the third lens group G3, and the fourth lens group. G4. In the figure, LPF is a low-pass filter, CG is a cover glass, and I is an image pickup surface of an electronic image pickup element.

  The first lens group G1 includes a negative meniscus lens L211 having a convex surface directed toward the object side, a prism L212, and a cemented lens of a biconvex lens L213 and a biconcave lens L214, and has a negative refracting power as a whole. .

  The second lens group G2 includes a cemented lens which is formed by a biconvex lens L221 and a negative meniscus lens L222 having a convex surface directed toward the image side, and has a positive refractive power as a whole.

  The third lens group G3 includes a cemented lens which is formed by a biconcave lens L231 and a positive meniscus lens L232 having a convex surface directed toward the object side, and has a negative refracting power as a whole.

  The fourth lens group G4 includes a cemented lens which is formed by a biconvex lens L241 and a negative meniscus lens L242 having a concave surface directed toward the object side, and has a positive refracting power as a whole.

  When zooming from the wide-angle end to the telephoto end, the first lens group G1 is fixed, the second lens group G2 is moved to the object side, the aperture stop S is fixed, and the third lens group G3 is moved to the image side. Then, the fourth lens group G4 moves to the image side.

  The aspherical surface is the object side surface of the biconvex lens L213 in the first lens group G1, the object side surface of the biconvex lens L221 in the second lens group G2, and the image side of the negative meniscus lens L222 with the convex surface facing the image side. On the object side surface of the biconvex lens L241 in the fourth lens group G4.

Next, numerical data of this embodiment will be listed.
Numerical data 14
r1 = 35.88
d1 = 1.1 Nd1 = 1.7432 νd1 = 49.34
r2 = 10.46
d2 = 3
r3 = ∞
d3 = 12.5 Nd3 = 1.801 νd3 = 34.97
r4 = ∞
d4 = 0.4
r5 = 41.274 (aspherical surface)
d5 = 2.2 Nd5 = 1.8061 νd5 = 40.92
r6 = -18.146
d6 = 0.7 Nd6 = 1.51823 νd6 = 58.9
r7 = 13.541
d7 = D7
r8 = 10.842 (aspherical surface)
d8 = 4 Nd8 = 1.497 νd8 = 81.54
r9 = -12
d9 = 0.35 Nd9 = 1.60687 νd9 = 27.03
r10 = -22.804 (aspherical surface)
d10 = D10
r11 = aperture
d11 = D11
r12 = -11.383
d12 = 0.7 Nd12 = 1.48749 νd12 = 70.23
r13 = 9.58
d13 = 1.6 Nd13 = 1.83481 νd13 = 42.71
r14 = 25.054
d14 = D14
r15 = 13.793 (Aspherical surface)
d15 = 3.5 Nd15 = 1.7432 νd15 = 49.34
r16 = -6
d16 = 0.7 Nd16 = 1.84666 νd16 = 23.78
r17 = -14.524
d17 = D17
r18 = ∞
d18 = 1.44 Nd18 = 1.54771 νd18 = 62.84
r19 = ∞
d19 = 0.8
r20 = ∞
d20 = 0.6 Nd20 = 1.51633 νd20 = 64.14
r21 = ∞
d21 = D21

Aspherical coefficient fifth surface
k = 0
A4 = 2.93525E-05
A6 = 4.07936E-07
A8 = 0.000E + 00
8th page
k = 0
A4 = -6.76006E-05
A6 = -2.34849E-07
A8 = -4.21441E-07
10th page
k = 0
A4 = 2.25820E-05
A6 = 5.99132E-07
A8 = -1.28129E-06
15th page
k = 0
A4 = -1.63254E-04
A6 = -9.51105E-07
A8 = 5.27383E-08

Zoom data
When D0 (distance from the object to the first surface) is ∞
Wide-angle end Middle Telephoto end
Focal length 6.011 13.702 17.986
FNO. 2.85 3.41 3.73
D7 13.83 4.09 0.8
D10 1.6 11.34 14.64
D11 1.4 5.76 8.78
D14 6.21 4.99 3
D17 5.32 2.18 1.15
D21 1.36 1.36 1.36

  FIG. 29 is a cross-sectional view along the optical axis showing the optical configuration at the time of focusing on an object point at infinity at the wide-angle end of the zoom lens according to Example 15 of the present invention.

  FIG. 30 is a diagram illustrating spherical aberration, astigmatism, distortion, and chromatic aberration of magnification when the zoom lens according to Example 15 is focused on an object point at infinity, where (a) is a wide angle end, (b) is an intermediate view, (c) shows the state at the telephoto end.

  As shown in FIG. 29, in the zoom lens of Example 15, the first lens group G1, the second lens group G2, the aperture stop S, the third lens group G3, and the fourth lens group are sequentially arranged from the object side. G4. In the figure, LPF is a low-pass filter, CG is a cover glass, and I is an image pickup surface of an electronic image pickup element.

  The first lens group G1 includes a negative meniscus lens L211 having a convex surface directed toward the object side, a prism L212, and a cemented lens of a biconvex lens L213 and a biconcave lens L214, and has a negative refracting power as a whole. .

  The second lens group G2 includes a cemented lens which is formed by a biconvex lens L221 and a negative meniscus lens L222 having a convex surface directed toward the image side, and has a positive refractive power as a whole.

  The third lens group G3 includes a cemented lens which is formed by a biconcave lens L231 and a positive meniscus lens L232 having a convex surface directed toward the object side, and has a negative refracting power as a whole.

  The fourth lens group G4 includes a cemented lens which is formed by a biconvex lens L241 and a negative meniscus lens L242 having a concave surface directed toward the object side, and has a positive refracting power as a whole.

  When zooming from the wide-angle end to the telephoto end, the first lens group G1 is fixed, the second lens group G2 is moved to the object side, the aperture stop S is fixed, and the third lens group G3 is moved to the image side. Then, the fourth lens group G4 moves to the image side.

  The aspherical surface is the object side surface of the biconvex lens L213 in the first lens group G1, the object side surface of the biconvex lens L221 in the second lens group G2, and the image side of the negative meniscus lens L222 with the convex surface facing the image side. On the object side surface of the biconvex lens L241 in the fourth lens group G4.

Next, numerical data of this embodiment will be listed.
Numerical data 15
r1 = 27.959
d1 = 1.1 Nd1 = 1.8061 νd1 = 40.92
r2 = 10.419
d2 = 3
r3 = ∞
d3 = 12.5 Nd3 = 1.801 νd3 = 34.97
r4 = ∞
d4 = 0.4
r5 = 2302.245 (aspherical surface)
d5 = 2.2 Nd5 = 1.8061 νd5 = 40.92
r6 = -13.25
d6 = 0.7 Nd6 = 1.51823 νd6 = 58.9
r7 = 19.658
d7 = D7
r8 = 13.858 (Aspherical surface)
d8 = 4 Nd8 = 1.51633 νd8 = 64.14
r9 = -12
d9 = 0.35 Nd9 = 1.60689 νd9 = 18.58
r10 = -18.551 (aspherical surface)
d10 = D10
r11 = aperture
d11 = D11
r12 = -12.567
d12 = 0.7 Nd12 = 1.48749 νd12 = 70.23
r13 = 10.171
d13 = 1.6 Nd13 = 1.833 νd13 = 37.16
r14 = 23.736
d14 = D14
r15 = 13.541 (aspherical surface)
d15 = 3.5 Nd15 = 1.7432 νd15 = 49.34
r16 = -6
d16 = 0.7 Nd16 = 1.84666 νd16 = 23.78
r17 = -15.389
d17 = D17
r18 = ∞
d18 = 1.44 Nd18 = 1.54771 νd18 = 62.84
r19 = ∞
d19 = 0.8
r20 = ∞
d20 = 0.6 Nd20 = 1.51633 νd20 = 64.14
r21 = ∞
d21 = D21

Aspherical coefficient fifth surface
k = 0
A4 = 1.94948E-05
A6 = 1.62504E-07
A8 = 0
8th page
k = 0
A4 = 2.80468E-04
A6 = -7.76543E-06
A8 = 0.000E + 00
10th page
k = 0
A4 = -6.44783E-06
A6 = -3.55641E-06
A8 = 0.000E + 00
15th page
k = 0
A4 = -1.50887E-04
A6 = 5.00830E-07
A8 = 0.000E + 00

Zoom data
When D0 (distance from the object to the first surface) is ∞
Wide-angle end Middle Telephoto end
Focal length 6.062 10.406 17.989
FNO. 2.85 3.29 3.9
D7 13.35 7.2 0.8
D10 1.58 7.74 14.14
D11 1.39 5.06 10.1
D14 7.11 5.69 2.99
D17 5.77 3.52 1.19
D21 1.36 1.36 1.36

  FIG. 31 is a cross-sectional view along the optical axis showing the optical configuration at the time of focusing on an object point at infinity at the wide-angle end of the zoom lens according to Example 16 of the present invention.

  FIG. 32 is a diagram illustrating spherical aberration, astigmatism, distortion, and lateral chromatic aberration when the zoom lens according to Example 16 is focused on an object point at infinity, where (a) is a wide-angle end, (b) is an intermediate view, (c) shows the state at the telephoto end.

  As shown in FIG. 31, the zoom lens of Example 16 includes, in order from the object side, a first lens group G1, a second lens group G2, an aperture stop S, a third lens group G3, and a fourth lens group. G4. In the figure, LPF is a low-pass filter, CG is a cover glass, and I is an image pickup surface of an electronic image pickup element.

  The first lens group G1 includes a negative meniscus lens L211 having a convex surface directed toward the object side, a prism L212, and a cemented lens of a biconvex lens L213 and a biconcave lens L214, and has a negative refracting power as a whole. .

  The second lens group G2 includes a cemented lens which is formed by a biconvex lens L221 and a negative meniscus lens L222 having a convex surface directed toward the image side, and has a positive refractive power as a whole.

  The third lens group G3 includes a cemented lens which is formed by a biconcave lens L231 and a positive meniscus lens L232 having a convex surface directed toward the object side, and has a negative refracting power as a whole.

  The fourth lens group G4 includes a cemented lens which is formed by a biconvex lens L241 and a negative meniscus lens L242 having a concave surface directed toward the object side, and has a positive refracting power as a whole.

  When zooming from the wide-angle end to the telephoto end, the first lens group G1 is fixed, the second lens group G2 is moved to the object side, the aperture stop S is fixed, and the third lens group G3 is moved to the image side. Then, the fourth lens group G4 moves to the image side.

  The aspherical surface is the object side surface of the biconvex lens L213 in the first lens group G1, the object side surface of the biconvex lens L221 in the second lens group G2, and the image side of the negative meniscus lens L222 with the convex surface facing the image side. On the object side surface of the biconvex lens L241 in the fourth lens group G4.

Next, numerical data of this embodiment will be listed.
Numerical data 16
r1 = 34.959
d1 = 1.1 Nd1 = 1.7432 νd1 = 49.34
r2 = 10.58
d2 = 3
r3 = ∞
d3 = 12.5 Nd3 = 1.801 νd3 = 34.97
r4 = ∞
d4 = 0.4
r5 = 40.088 (aspherical surface)
d5 = 2.2 Nd5 = 1.8061 νd5 = 40.92
r6 = -17.816
d6 = 0.7 Nd6 = 1.51823 νd6 = 58.9
r7 = 13.677
d7 = D7
r8 = 10.733 (aspherical surface)
d8 = 4 Nd8 = 1.497 νd8 = 81.54
r9 = -12
d9 = 0.35 Nd9 = 1.69556 νd9 = 25.02.
r10 = -22.311 (Aspherical surface)
d10 = D10
r11 = aperture
d11 = D11
r12 = -11.366
d12 = 0.7 Nd12 = 1.48749 νd12 = 70.23
r13 = 9.599
d13 = 1.6 Nd13 = 1.83481 νd13 = 42.71
r14 = 24.942
d14 = D14
r15 = 13.911 (Aspherical surface)
d15 = 3.5 Nd15 = 1.7432 νd15 = 49.34
r16 = -6
d16 = 0.7 Nd16 = 1.84666 νd16 = 23.78
r17 = -14.707
d17 = D17
r18 = ∞
d18 = 1.44 Nd18 = 1.54771 νd18 = 62.84
r19 = ∞
d19 = 0.8
r20 = ∞
d20 = 0.6 Nd20 = 1.51633 νd20 = 64.14
r21 = ∞
d21 = D21

Aspherical coefficient fifth surface
k = 0
A4 = 3.14995E-05
A6 = 2.53620E-07
A8 = 0
8th page
k = 0
A4 = -6.23568E-05
A6 = -2.89371E-07
A8 = 0.000E + 00
10th page
k = 0
A4 = 1.993955E-05
A6 = 2.23840E-07
A8 = 0.000E + 00
15th page
k = 0
A4 = -1.66755E-04
A6 = 4.47680E-07
A8 = 0.000E + 00

Zoom data
When D0 (distance from the object to the first surface) is ∞
Wide-angle end Middle Telephoto end
Focal length 6.274 13.898 18.212
FNO. 2.89 3.44 3.75
D7 13.83 4.09 0.8
D10 1.6 11.34 14.64
D11 1.4 5.76 8.78
D14 6.21 4.99 3
D17 5.32 2.18 1.15
D21 1.73 1.86 1.77

  FIG. 33 is a cross-sectional view along the optical axis showing an optical configuration at the time of focusing on an object point at infinity at the wide-angle end of a zoom lens according to Example 17 of the present invention.

  FIG. 34 is a diagram showing spherical aberration, astigmatism, distortion, and chromatic aberration of magnification when the zoom lens according to Example 17 is focused on an object point at infinity, where (a) is the wide-angle end, (b) is the middle, (c) shows the state at the telephoto end.

  As shown in FIG. 33, the zoom lens of Example 17 includes a first lens group G1, a second lens group G2, an aperture stop S, a third lens group G3, and a fourth lens group in order from the object side. G4. In the figure, LPF is a low-pass filter, CG is a cover glass, and I is an image pickup surface of an electronic image pickup element.

  The first lens group G1 includes a negative meniscus lens L211 having a convex surface directed toward the object side, a prism L212, and a cemented lens of a positive meniscus lens L213 having a convex surface directed toward the image side and a biconcave lens L214. It has a refractive power of

  The second lens group G2 includes a cemented lens which is formed by a biconvex lens L221 and a negative meniscus lens L222 having a convex surface directed toward the image side, and has a positive refractive power as a whole.

  The third lens group G3 includes a cemented lens which is formed by a biconcave lens L231 and a positive meniscus lens L232 having a convex surface directed toward the object side, and has a negative refracting power as a whole.

  The fourth lens group G4 includes a cemented lens which is formed by a biconvex lens L241 and a negative meniscus lens L242 having a concave surface directed toward the object side, and has a positive refracting power as a whole.

  When zooming from the wide-angle end to the telephoto end, the first lens group G1 is fixed, the second lens group G2 is moved to the object side, the aperture stop S is fixed, and the third lens group G3 is moved to the image side. Then, the fourth lens group G4 moves to the image side.

  The aspherical surface has the object side surface of the positive meniscus lens L213 having a convex surface facing the image side in the first lens group G1, the object side surface of the biconvex lens L221 in the second lens group G2, and the convex surface facing the image side. The negative meniscus lens L222 is provided on the image side surface, and on the object side surface of the biconvex lens L241 in the fourth lens group G4.

Next, numerical data of this embodiment will be listed.
Numerical data 17
r1 = 25.752
d1 = 1.1 Nd1 = 1.804 νd1 = 46.57
r2 = 11.454
d2 = 3
r3 = ∞
d3 = 12.5 Nd3 = 1.801 νd3 = 34.97
r4 = ∞
d4 = 0.4
r5 = -50.569 (aspherical surface)
d5 = 2.2 Nd5 = 1.8061 νd5 = 40.92
r6 = -44.029
d6 = 0.7 Nd6 = 1.51823 νd6 = 58.9
r7 = 22.199
d7 = D7
r8 = 10.827 (Aspherical surface)
d8 = 4 Nd8 = 1.51633 νd8 = 64.14
r9 = -12
d9 = 0.35 Nd9 = 1.72568 νd9 = 18.68
r10 = -13.508 (aspherical surface)
d10 = D10
r11 = aperture
d11 = D11
r12 = -34.096
d12 = 0.7 Nd12 = 1.51823 νd12 = 58.9
r13 = 9.63
d13 = 1.6 Nd13 = 1.816 νd13 = 46.62
r14 = 14.496
d14 = D14
r15 = 14.344 (Aspherical surface)
d15 = 3.5 Nd15 = 1.7432 νd15 = 49.34
r16 = -6
d16 = 0.7 Nd16 = 1.84666 νd16 = 23.78
r17 = -17.129
d17 = D17
r18 = ∞
d18 = 1.44 Nd18 = 1.54771 νd18 = 62.84
r19 = ∞
d19 = 0.8
r20 = ∞
d20 = 0.6 Nd20 = 1.51633 νd20 = 64.14
r21 = ∞
d21 = D21

Aspherical coefficient fifth surface
k = 0
A4 = 5.21908E-05
A6 = -4.28063E-08
A8 = 0
8th page
k = 0
A4 = 1.63431E-04
A6 = -1.97723E-06
A8 = 0.000E + 00
10th page
k = 0
A4 = 1.01894E-04
A6 = -8.53272E-07
A8 = 0.000E + 00
15th page
k = 0
A4 = -1.18081E-04
A6 = 9.84689E-07
A8 = 0.000E + 00

Zoom data
When D0 (distance from the object to the first surface) is ∞
Wide-angle end Middle Telephoto end
Focal length 6.276 10.303 17.983
FNO. 2.85 2.9 3.56
D7 12.32 6.49 0.8
D10 1.63 7.34 13.14
D11 1.43 1.02 9.61
D14 8.72 10.15 2.97
D17 3.72 2.7 1.28
D21 1.36 1.36 1.36

  FIG. 35 is a sectional view taken along the optical axis showing the optical configuration at the time of focusing on an object point at infinity at the wide-angle end of the zoom lens according to Example 18 of the present invention.

  FIG. 36 is a diagram showing spherical aberration, astigmatism, distortion, and lateral chromatic aberration when the zoom lens according to Example 18 is focused on an object point at infinity, where (a) is the wide-angle end, (b) is the middle, (c) shows the state at the telephoto end.

  As shown in FIG. 35, the zoom lens of Example 18 includes, in order from the object side, the first lens group G1, the second lens group G2, the aperture stop S, the third lens group G3, and the fourth lens group. G4. In the figure, LPF is a low-pass filter, CG is a cover glass, and I is an image pickup surface of an electronic image pickup element.

  The first lens group G1 includes a negative meniscus lens L211 having a convex surface directed toward the object side, a prism L212, and a cemented lens of a positive meniscus lens L213 having a convex surface directed toward the image side and a biconcave lens L214. It has a refractive power of

  The second lens group G2 includes a cemented lens which is formed by a biconvex lens L221 and a negative meniscus lens L222 having a convex surface directed toward the image side, and has a positive refractive power as a whole.

  The third lens group G3 includes a cemented lens which is formed by a biconcave lens L231 and a positive meniscus lens L232 having a convex surface directed toward the object side, and has a negative refracting power as a whole.

  The fourth lens group G4 includes a cemented lens which is formed by a biconvex lens L241 and a negative meniscus lens L242 having a concave surface directed toward the object side, and has a positive refracting power as a whole.

  When zooming from the wide-angle end to the telephoto end, the first lens group G1 is fixed, the second lens group G2 is moved to the object side, the aperture stop S is fixed, and the third lens group G3 is moved to the image side. Then, the fourth lens group G4 moves to the image side.

  The aspherical surface has the object side surface of the positive meniscus lens L213 having a convex surface facing the image side in the first lens group G1, the object side surface of the biconvex lens L221 in the second lens group G2, and the convex surface facing the image side. The negative meniscus lens L222 is provided on the image side surface, and on the object side surface of the biconvex lens L241 in the fourth lens group G4.

Next, numerical data of this embodiment will be listed.
Numerical data 18
r1 = 25.752
d1 = 1.1 Nd1 = 1.804 νd1 = 46.57
r2 = 11.454
d2 = 3
r3 = ∞
d3 = 12.5 Nd3 = 1.801 νd3 = 34.97
r4 = ∞
d4 = 0.4
r5 = -50.569 (aspherical surface)
d5 = 2.2 Nd5 = 1.8061 νd5 = 40.92
r6 = -44.029
d6 = 0.7 Nd6 = 1.51823 νd6 = 58.9
r7 = 22.199
d7 = D7
r8 = 10.827 (aspherical surface)
d8 = 4 Nd8 = 1.51633 νd8 = 64.14
r9 = -12
d9 = 0.35 Nd9 = 1.72568 νd9 = 18.68
r10 = -13.508 (Aspherical surface)
d10 = D10
r11 = aperture
d11 = D11
r12 = -34.096
d12 = 0.7 Nd12 = 1.51823 νd12 = 58.9
r13 = 9.63
d13 = 1.6 Nd13 = 1.816 νd13 = 46.62
r14 = 14.496
d14 = D14
r15 = 14.344 (Aspherical surface)
d15 = 3.5 Nd15 = 1.7432 νd15 = 49.34
r16 = -6
d16 = 0.7 Nd16 = 1.84666 νd16 = 23.78
r17 = -17.129
d17 = D17
r18 = ∞
d18 = 1.44 Nd18 = 1.54771 νd18 = 62.84
r19 = ∞
d19 = 0.8
r20 = ∞
d20 = 0.6 Nd20 = 1.51633 νd20 = 64.14
r21 = ∞
d21 = D21

Aspherical coefficient fifth surface
k = 0
A4 = 5.21908E-05
A6 = -4.28063E-08
A8 = 0
8th page
k = 0
A4 = 1.63431E-04
A6 = -1.97723E-06
A8 = 0.000E + 00
10th page
k = 0
A4 = 1.01894E-04
A6 = -8.53272E-07
A8 = 0.000E + 00
15th page
k = 0
A4 = -1.18081E-04
A6 = 9.84689E-07
A8 = 0.000E + 00

Zoom data
When D0 (distance from the object to the first surface) is ∞
Wide-angle end Middle Telephoto end
Focal length 6.276 10.303 17.983
FNO. 2.85 2.9 3.56
D7 12.32 6.49 0.8
D10 1.63 7.34 13.14
D11 1.43 1.02 9.61
D14 8.72 10.15 2.97
D17 3.72 2.7 1.28
D21 1.36 1.36 1.36

  The imaging optical system of the present invention as described above is a photographing apparatus for photographing an image of an object with an electronic image sensor such as a CCD or a CMOS, especially a digital camera, a video camera, a personal computer or an example of an information processing apparatus, a telephone. It can be used for portable terminals, especially mobile phones that are convenient to carry. The embodiment is illustrated below.

  FIG. 37 to FIG. 39 are conceptual diagrams of a configuration in which the imaging optical system according to the present invention is incorporated in a photographing optical system 41 of a digital camera. 37 is a front perspective view showing the appearance of the digital camera 40, FIG. 38 is a rear perspective view thereof, and FIG. 39 is a cross-sectional view showing an optical configuration of the digital camera 40.

  In this example, the digital camera 40 includes a photographing optical system 41 having a photographing optical path 42, a finder optical system 43 having a finder optical path 44, a shutter 45, a flash 46, a liquid crystal display monitor 47, and the like. Then, when the photographer presses the shutter 45 disposed on the upper part of the camera 40, the photographing is performed through the photographing optical system 41, for example, the zoom lens of the first embodiment in conjunction therewith.

  The object image formed by the photographing optical system 41 is formed on the image pickup surface of the CCD 49. The object image received by the CCD 49 is displayed as an electronic image on the liquid crystal display monitor 47 provided on the back of the camera via the image processing means 51. Further, the image processing means 51 is provided with a memory or the like, and can record a captured electronic image. This memory may be provided separately from the image processing means 51, or may be configured to perform recording and writing electronically using a floppy (registered trademark) disk, memory card, MO, or the like.

  Further, a finder objective optical system 53 is disposed on the finder optical path 44. The finder objective optical system 53 includes a cover lens 54, a first prism 10, an aperture stop 2, a second prism 20, and a focusing lens 66. An object image is formed on the imaging surface 67 by the finder objective optical system 53. This object image is formed on the field frame 57 of the Porro prism 55 which is an image erecting member. An eyepiece optical system 59 that guides an erect image to the observer eyeball E is disposed behind the polyprism 55.

  According to the digital camera 40 configured as described above, an electronic imaging device having a compact and thin zoom lens in which the number of components of the photographing optical system 41 is reduced can be realized.

  Next, a personal computer which is an example of an information processing apparatus in which the imaging optical system of the present invention is built as an objective optical system is shown in FIGS. 40 is a front perspective view of the personal computer 300 with the cover open, FIG. 41 is a sectional view of the photographing optical system 303 of the personal computer 300, and FIG. 42 is a side view of FIG. As shown in FIGS. 40 to 42, the personal computer 300 includes a keyboard 301, information processing means and recording means, a monitor 302, and a photographing optical system 303.

  Here, the keyboard 301 is for an operator to input information from the outside. The information processing means and recording means are not shown. The monitor 302 is for displaying information to the operator. The photographing optical system 303 is for photographing an image of the operator himself or a surrounding area. The monitor 302 may be a liquid crystal display element, a CRT display, or the like. Examples of the liquid crystal display element include a transmissive liquid crystal display element that illuminates from the back with a backlight (not shown), and a reflective liquid crystal display element that reflects and displays light from the front. Further, in the drawing, the photographing optical system 303 is built in the upper right of the monitor 302. However, the imaging optical system 303 is not limited to the place, and may be anywhere around the monitor 302 or the keyboard 301.

  The photographing optical system 303 includes, on the photographing optical path 304, the objective optical system 100 including, for example, the zoom lens according to the first embodiment, and the electronic imaging element chip 162 that receives an image. These are built in the personal computer 300.

A cover glass 102 for protecting the objective optical system 100 is disposed at the tip of the mirror frame.
The object image received by the electronic image sensor chip 162 is input to the processing means of the personal computer 300 via the terminal 166. Finally, the object image is displayed on the monitor 302 as an electronic image. FIG. 40 shows an image 305 taken by the operator as an example. The image 305 can also be displayed on a communication partner's personal computer from a remote location via the processing means. The Internet and telephone are used for image transmission to remote places.

  Next, FIG. 43 shows a telephone which is an example of an information processing apparatus in which the imaging optical system of the present invention is incorporated as a photographing optical system, particularly a portable telephone which is convenient to carry. 43 (a) is a front view of the mobile phone 400, FIG. 43 (b) is a side view, and FIG. 43 (c) is a cross-sectional view of the photographing optical system 405. 43A to 43C, the mobile phone 400 includes a microphone unit 401, a speaker unit 402, an input dial 403, a monitor 404, a photographing optical system 405, an antenna 406, and processing. Means.

  Here, the microphone unit 401 is for inputting an operator's voice as information. The speaker unit 402 is for outputting the voice of the other party. An input dial 403 is used by an operator to input information. The monitor 404 is for displaying information such as a photographed image of the operator himself or the other party, a telephone number, and the like. The antenna 406 is for transmitting and receiving communication radio waves. The processing means (not shown) is for processing image information, communication information, input signals, and the like.

  Here, the monitor 404 is a liquid crystal display element. Further, in the drawing, the arrangement positions of the respective components, in particular, are not limited thereto. The photographing optical system 405 includes the objective optical system 100 disposed on the photographing optical path 407 and an electronic image sensor chip 162 that receives an object image. As the objective optical system 100, for example, the zoom lens of Example 1 is used. These are built in the mobile phone 400.

A cover glass 102 for protecting the objective optical system 100 is disposed at the tip of the mirror frame.
The object image received by the electronic imaging element chip 162 is input to an image processing unit (not shown) via the terminal 166. Finally, the object image is displayed as an electronic image on the monitor 404, the monitor of the communication partner, or both. The processing means includes a signal processing function. When transmitting an image to a communication partner, this function converts information on the object image received by the electronic image sensor chip 162 into a signal that can be transmitted.

  FIG. 44 is a cross-sectional view along the optical axis showing the optical configuration at the time of focusing on an object point at infinity at the wide angle end of the zoom lens according to Example 20 of the present invention.

  FIG. 45 is a diagram illustrating spherical aberration, astigmatism, distortion, and chromatic aberration of magnification when the zoom lens according to Example 20 is focused on an object point at infinity, where (a) is a wide angle end, (b) is an intermediate view, (c) shows the state at the telephoto end. Hereinafter, the number of wavelengths and the types of lines are different from those in the above embodiments.

  As shown in FIG. 44, in the zoom lens of Example 20, the first lens group G1, the second lens group G2, the aperture stop S, the third lens group G3, and the fourth lens group are sequentially arranged from the object side. G4. In the figure, LPF is a low-pass filter, CG is a cover glass, and I is an image pickup surface of an electronic image pickup element.

  The first lens group G1 is composed of a cemented lens of a biconvex lens L311 and a biconcave lens L312 and has a positive refractive power as a whole.

  The second lens group G2 includes a negative meniscus lens L321 having a convex surface directed toward the object side, a biconcave lens L322, and a positive meniscus lens L323 having a convex surface directed toward the object side, and has a negative refracting power as a whole. doing.

  The third lens group G3 includes a biconvex lens L331, a cemented lens of a positive meniscus lens L332 having a convex surface directed toward the object side, and a negative meniscus lens L333 having a convex surface directed toward the object side, and has a positive refracting power as a whole. have.

  The fourth lens group G4 includes a positive meniscus lens L341 having a convex surface directed toward the object side, and has a positive refracting power as a whole.

  When zooming from the wide-angle end to the telephoto end, the first lens group G1 once moves to the image side and then moves to the object side, the second lens group G2 moves to the image side, and the third lens group G3. Moves to the object side, and the fourth lens group G4 once moves to the object side and then moves to the image side. The aperture stop S moves together with the third lens group G3.

  The aspheric surfaces are the image side surface of the biconcave lens L312 in the first lens group G1, the object side surface of the biconcave lens L322 in the second lens group G2, the both surfaces of the biconvex lens L331 in the third lens group G3, It is provided on the object side surface of a positive meniscus lens L341 having a convex surface facing the object side in the four lens group G4.

Next, numerical data of this embodiment will be listed.
Numerical data 20
r1 = 24.6708
d1 = 4.5035 Nd1 = 1.60311 νd1 = 60.64
r2 = −54.6584
d2 = 0.1000 Nd2 = 1.63494 νd2 = 22.00
r3 = 3841.8322 (Aspherical surface)
d3 = D3
r4 = 49.2876
d4 = 0.8000 Nd4 = 1.88300 νd4 = 40.76
r5 = 7.9694
d5 = 3.7724
r6 = -28.7087 (Aspherical surface)
d6 = 0.000 Nd6 = 1.77377 νd6 = 47.18
r7 = 43.8402
d7 = 0.000
r8 = 16.2635
d8 = 2.0009 Nd8 = 1.94595 νd8 = 17.98
r9 = 57.3872
d9 = D9
r10 = aperture d10 = 0.4000
r11 = 11.3688 (Aspherical surface)
d11 = 1.7683 Nd11 = 1.69350 νd11 = 53.18
r12 = -49.9476 (Aspherical surface)
d12 = 0.000
r13 = 6.4852
d13 = 2.3553 Nd13 = 1.490000 νd13 = 81.54
r14 = 13.0225
d14 = 1.1169 Nd14 = 1.84666 νd14 = 23.78
r15 = 4.9715
d15 = D15
r16 = 18.3856 (Aspherical surface)
d16 = 1.5168 Nd16 = 1.69350 νd16 = 53.18
r17 = 152.7758
d17 = D17
r18 = ∞
d18 = 0.9010 Nd18 = 1.54771 νd18 = 62.84
r19 = ∞
d19 = 0.5300
r20 = ∞
d20 = 0.5300 Nd20 = 1.51633 νd20 = 64.14
r21 = ∞
d21 = D21

Aspheric coefficient third surface
K = 0
A4 = 3.9128E-06
A6 = 0.000E + 00
A8 = 0.000E + 00
6th page
K = 0
A4 = -8.7213E-06
A6 = -2.5912E-07
A8 = 0.000E + 00
11th page
K = -0.7003
A4 = 3.9515E-05
A6 = 4.3601E-06
A8 = 1.9220E-07
12th page
K = 0
A4 = 9.7498E-05
A6 = 4.9898E-06
A8 = 1.9933E-07
16th page
K = 0
A4 = 1.6770E-05
A6 = -2.7818E-07
A8 = 4.9273E-08

When zoom data D0 (distance from object to first surface) is ∞
Wide-angle end Middle Telephoto end
Focal length 6.69470 20.87811 65.60809
FNO. 3.1522 3.9455 4.9321
D3 0.20000 10.15056 21.62290
D9 30.50397 9.17559 1.59000
D15 8.69705 7.70392 21.07950
D17 4.52380 11.53900 3.11258
D21 0.51826 0.51826 0.51826

Refractive index table lens 587.56 656.27 486.13 435.84
L312 1.634937 1.626943 1.655801 1.674778
LPF 1.547710 1.545046 1.553762 1.558427
L323 1.945950 1.931230 1.983830 2.018247
L331, L341 1.693500 1.689551 1.702591 1.709739
L322 1.773770 1.768840 1.785240 1.794357
CG 1.516330 1.513855 1.521905 1.526213
L311 1.603112 1.600079 1.610024 1.615408
L332 1.496999 1.495136 1.501231 1.504506
L321 1.882997 1.876560 1.898221 1.910495
L333 1.846660 1.836488 1.872096 1.894186

  FIG. 46 is a cross-sectional view along the optical axis showing an optical configuration at the time of focusing on an object point at infinity at the wide angle end of the zoom lens according to Example 21 of the present invention.

  47 is a diagram showing spherical aberration, astigmatism, distortion, and chromatic aberration of magnification when the zoom lens according to Example 21 is focused on an object point at infinity, where (a) is the wide-angle end, (b) is the middle, (c) shows the state at the telephoto end.

  As shown in FIG. 46, in the zoom lens of Example 21, the first lens group G1, the second lens group G2, the aperture stop S, the third lens group G3, and the fourth lens group are sequentially arranged from the object side. G4 and the fifth lens group G5 are included. In the figure, CG is a cover glass, and I is an image pickup surface of an electronic image pickup element.

  The first lens group G1 includes a cemented lens which includes a biconvex lens L411 and a negative meniscus lens 412 having a convex surface directed toward the image side, and has a positive refractive power as a whole.

  The second lens group G2 includes a negative meniscus lens L421 having a convex surface facing the object side, a prism L422, a negative meniscus lens L423 having a convex surface facing the object side, and a positive meniscus lens L424 having a convex surface facing the object side. It has a negative refractive power as a whole.

  The third lens group G3 includes a cemented lens including a positive meniscus lens L431 having a convex surface directed toward the object side, a positive meniscus lens L432 having a convex surface directed toward the object side, and a negative meniscus lens L433 having a convex surface directed toward the object side. And has a positive refractive power as a whole.

  The fourth lens group G4 includes a positive meniscus lens L441 having a convex surface directed toward the object side, and has a positive refracting power as a whole.

  The fifth lens group G5 includes a positive meniscus lens L451 having a convex surface directed toward the object side, and has a positive refracting power as a whole.

  When zooming from the wide-angle end to the telephoto end, the first lens group G1 moves to the object side, the second lens group G2 is fixed, the third lens group G3 moves to the object side, and the fourth lens group G4 moves to the object side, and the fifth lens group G5 is fixed. The aperture stop S moves together with the third lens group G3.

  The aspherical surface is an image side surface of the negative meniscus lens L412 having a convex surface facing the image side in the first lens group G1, and an image side surface of the negative meniscus lens L421 having a convex surface facing the object side in the second lens group G2. On the object side surface of the positive meniscus lens L431 with the convex surface facing the object side in the third lens group G3, and on the image side surface of the positive meniscus lens L451 with the convex surface facing the object side in the fifth lens group G5. Is provided.

Next, numerical data of this embodiment will be listed.
Numerical data 21
r1 = 51.2139
d1 = 4.5000 Nd1 = 1.61800 νd1 = 63.33
r2 = -118.6920
d2 = 0.1000 Nd2 = 1.63500 νd2 = 23.00
r3 = -385.6819 (Aspherical surface)
d3 = D3
r4 = 1165.6880
d4 = 0.8000 Nd4 = 1.69350 νd4 = 53.21
r5 = 11.2058 (Aspherical surface)
d5 = 3.1000
r6 = ∞
d6 = 13.600 Nd6 = 1.77250 νd6 = 49.60
r7 = ∞
d7 = 0.3000
r8 = 337.7559
d8 = 0.7000 Nd8 = 1.69350 νd8 = 53.21
r9 = 16.7250
d9 = 1.2000
r10 = 15.9332
d10 = 1.8000 Nd10 = 1.92286 νd10 = 18.90
r11 = 25.4835
d11 = D11
r12 = aperture d12 = 0.5000
r13 = 12.8952 (aspherical surface)
d13 = 2.7000 Nd13 = 1.48348 νd13 = 42.71
r14 = 143.9466
d14 = 0.1500
r15 = 7.9738
d15 = 2.7000 Nd15 = 1.77250 νd15 = 49.60
r16 = 23.4510
d16 = 0.5000 Nd16 = 1.80810 νd16 = 2.76
r17 = 5.4032
d17 = D17
r18 = 14.7875
d18 = 2.000 Nd18 = 1.69680 νd18 = 55.53
r19 = 33.1164
d19 = D19
r20 = 12.9577
d20 = 2.000 Nd20 = 1.69350 νd20 = 53.21
r21 = 22.4152 (Aspherical surface)
d21 = 1.4000
r22 = ∞
d22 = 1.2000 Nd22 = 1.51633 νd22 = 64.14
r23 = ∞
d23 = D23

Aspheric coefficient third surface
K = -0.6545
A4 = 4.2474E-06
A6 = -1.8414E-08
A8 = 0.000E + 00
5th page
K = 0
A4 = -6.3182E-05
A6 = 7.0067E-07
A8 = -6.5097E-09
Side 13
K = 0
A4 = -4.0903E-05
A6 = 1.8145E-07
A8 = -7.2312E-09
21st page
K = -0.1983
A4 = -1.5838E-05
A6 = 1.0103E-05
A8 = 0.000E + 00

When zoom data D0 (distance from object to first surface) is ∞
Wide-angle end Middle Telephoto end
Focal length 6.20287 13.86941 30.99869
FNO. 2.8000 3.8112 5.0392
D3 0.80033 13.29380 21.17200
D11 23.83351 12.80928 1.80027
D17 4.04933 13.83788 10.02916
D19 6.80747 8.04951 22.86068
D23 1.50072 1.50072 1.50072

Refractive index table lens 587.56 656.27 486.13 435.83
L412 1.634997 1.627304 1.654909 1.672841
CG 1.516330 1.513855 1.521905 1.526214
L431 1.834807 1.828975 1.848520 1.859548
L422, L432 1.772499 1.767798 1.783374 1.791972
L421, L423, L451 1.693501 1.689548 1.702582 1.709715
L441 1.696797 1.692974 1.705522 1.712340
L433 1.808095 1.798009 1.833513 1.855904
L424 1.922860 1.909158 1.957996 1.989717
L411 1.618000 1.615036 1.624794 1.630103

  As described above, the imaging optical system of the present invention and the electronic imaging device using the same have the following features in addition to the invention described in the claims.

(1) The imaging optical system according to claim 1, wherein the following conditional expression is satisfied.
1.48 <β <2.04
Here, Nd represents the refractive index of the glass material used for the cemented lens, and νd represents the Abbe number of the glass material used for the cemented lens, and satisfies the relationship Nd = α × νd + β.

(2) The imaging optical system according to claim 1, wherein the following conditional expression is satisfied.
1.50 <β <2.00
Here, Nd represents the refractive index of the glass material used for the cemented lens, and νd represents the Abbe number of the glass material used for the cemented lens, and satisfies the relationship Nd = α × νd + β.

(3) The imaging optical system according to claim 1, wherein the following conditional expression is satisfied.
1.58 <Nd <1.95
Nd is the refractive index of the glass material used for the cemented lens.

(4) The imaging optical system according to claim 1, wherein the following conditional expression is satisfied.
1.63 <Nd <1.87
Nd is the refractive index of the glass material used for the cemented lens.

(5) The imaging optical system according to claim 1, wherein the following conditional expression is satisfied.
20 <νd <45
Where νd is the Abbe number of the glass material used for the cemented lens.

(6) The imaging optical system according to claim 1, wherein the following conditional expression is satisfied.
25 <νd <40
Where νd is the Abbe number of the glass material used for the cemented lens.

(7) The electronic imaging apparatus according to (10), wherein the zoom lens satisfies the following conditional expression when focusing on an object point at infinity.
0.75 <y ₀₇ / (fw · tan ω _07w ) <0.94
However, y ₀₇ is y ₀₇ = 0.7y ₁₀ , where y ₁₀ is the distance (maximum image height) from the center to the farthest point in the effective imaging plane (in the plane where imaging is possible) of the electronic imaging device. expressed. Further, ω _07w is an angle with respect to the optical axis in the object point direction corresponding to the image point connecting from the center on the imaging surface to the position of y ₀₇ at the wide angle end.

(8) The electronic imaging apparatus according to (10), wherein the zoom lens satisfies the following conditional expression when focusing on an object point at infinity.
0.80 <y ₀₇ / (fw · tan ω _07w ) <0.92
However, y ₀₇ is y ₀₇ = 0.7y ₁₀ , where y ₁₀ is the distance (maximum image height) from the center to the farthest point in the effective imaging plane (in the plane where imaging is possible) of the electronic imaging device. expressed. Further, ω _07w is an angle with respect to the optical axis in the object point direction corresponding to the image point connecting from the center on the imaging surface to the position of y ₀₇ at the wide angle end.

  The present invention can take various modifications without departing from the spirit of the present invention.

It is sectional drawing which follows the optical axis which shows the optical structure at the time of infinity object point focusing in the wide angle end of the zoom lens concerning Example 1 of this invention. FIG. 3 is a diagram illustrating spherical aberration, astigmatism, distortion, and chromatic aberration of magnification when the zoom lens according to Example 1 is focused on an object point at infinity, where (a) is the wide-angle end, (b) is the middle, (c) Indicates the state at the telephoto end. It is sectional drawing which follows the optical axis which shows the optical structure at the time of infinity object point focusing in the wide angle end of the zoom lens concerning Example 2 of this invention. FIG. 7 is a diagram illustrating spherical aberration, astigmatism, distortion, and lateral chromatic aberration when the zoom lens according to Example 2 is focused on an object point at infinity, where (a) is a wide-angle end, (b) is an intermediate, (c) Indicates the state at the telephoto end. It is sectional drawing which follows the optical axis which shows the optical structure at the time of infinity object point focusing in the wide angle end of the zoom lens concerning Example 3 of this invention. FIG. 10 is a diagram illustrating spherical aberration, astigmatism, distortion, and chromatic aberration of magnification when the zoom lens according to Example 3 is focused on an object point at infinity, where (a) is a wide-angle end, (b) is a middle, (c) Indicates the state at the telephoto end. It is sectional drawing which follows the optical axis which shows the optical structure at the time of infinity object point focusing in the wide angle end of the zoom lens concerning Example 4 of this invention. FIG. 10 is a diagram illustrating spherical aberration, astigmatism, distortion, and chromatic aberration of magnification when the zoom lens according to Example 4 is focused on an object point at infinity, where (a) is a wide-angle end, (b) is a middle, (c) Indicates the state at the telephoto end. FIG. 10 is a cross-sectional view along an optical axis showing an optical configuration at the time of focusing on an object point at infinity at the wide angle end of a zoom lens according to Example 5 of the present invention; FIG. 10 is a diagram illustrating spherical aberration, astigmatism, distortion, and chromatic aberration of magnification when the zoom lens according to Example 5 is focused on an object point at infinity, where (a) is a wide-angle end, (b) is a middle, (c) Indicates the state at the telephoto end. It is sectional drawing which follows the optical axis which shows the optical structure at the time of infinity object point focusing in the wide angle end of the zoom lens concerning Example 6 of this invention. FIG. 10 is a diagram illustrating spherical aberration, astigmatism, distortion, and chromatic aberration of magnification when the zoom lens according to Example 6 is focused on an object point at infinity, where (a) is a wide-angle end, (b) is a middle, (c) Indicates the state at the telephoto end. It is sectional drawing which follows the optical axis which shows the optical structure at the time of infinity object point focusing in the wide angle end of the zoom lens concerning Example 7 of this invention. FIG. 10 is a diagram illustrating spherical aberration, astigmatism, distortion, and chromatic aberration of magnification when the zoom lens according to Example 7 is focused on an object point at infinity, where (a) is a wide-angle end, (b) is a middle, (c) Indicates the state at the telephoto end. It is sectional drawing which follows the optical axis which shows the optical structure at the time of infinity object point focusing in the wide angle end of the zoom lens concerning Example 8 of this invention. FIG. 10 is a diagram illustrating spherical aberration, astigmatism, distortion aberration, and chromatic aberration of magnification when the zoom lens according to Example 8 is focused on an object point at infinity, where (a) is a wide-angle end, (b) is an intermediate position, (c) Indicates the state at the telephoto end. It is sectional drawing which follows the optical axis which shows the optical structure at the time of an infinite object point focusing in the wide angle end of the zoom lens concerning Example 9 of this invention. FIG. 10 is a diagram illustrating spherical aberration, astigmatism, distortion, and chromatic aberration of magnification when the zoom lens according to Example 9 is focused on an object point at infinity, where (a) is a wide-angle end, (b) is an intermediate, and (c). Indicates the state at the telephoto end. It is sectional drawing which follows the optical axis which shows the optical structure at the time of infinity object point focusing in the wide angle end of the zoom lens concerning Example 10 of this invention. FIG. 11 is a diagram illustrating spherical aberration, astigmatism, distortion, and lateral chromatic aberration when the zoom lens according to Example 10 is focused on an object point at infinity, where (a) is a wide-angle end, (b) is an intermediate, (c) Indicates the state at the telephoto end. It is sectional drawing which follows the optical axis which shows the optical structure at the time of infinity object point focusing in the wide angle end of the zoom lens concerning Example 11 of this invention. FIG. 10 is a diagram illustrating spherical aberration, astigmatism, distortion, and lateral chromatic aberration when the zoom lens according to Example 11 is focused on an object point at infinity, where (a) is a wide-angle end, (b) is an intermediate, (c) Indicates the state at the telephoto end. It is sectional drawing which follows the optical axis which shows the optical structure at the time of infinity object point focusing in the wide angle end of the zoom lens concerning Example 12 of this invention. FIG. 14 is a diagram showing spherical aberration, astigmatism, distortion, and chromatic aberration of magnification when the zoom lens according to Example 12 is focused on an object point at infinity, where (a) is a wide-angle end, (b) is an intermediate, (c) Indicates the state at the telephoto end. It is sectional drawing which follows the optical axis which shows the optical structure at the time of infinity object point focusing in the wide angle end of the zoom lens concerning Example 13 of this invention. FIG. 14 is a diagram illustrating spherical aberration, astigmatism, distortion, and chromatic aberration of magnification when the zoom lens according to Example 13 is focused on an object point at infinity, where (a) is a wide-angle end, (b) is a middle, (c) Indicates the state at the telephoto end. It is sectional drawing which follows the optical axis which shows the optical structure at the time of infinity object point focusing in the wide angle end of the zoom lens concerning Example 14 of this invention. FIG. 14 is a diagram showing spherical aberration, astigmatism, distortion aberration, and chromatic aberration of magnification when the zoom lens according to Example 14 is focused on an object point at infinity, where (a) is a wide angle end, (b) is an intermediate position, (c) Indicates the state at the telephoto end. It is sectional drawing which follows the optical axis which shows the optical structure at the time of infinity object point focusing in the wide angle end of the zoom lens concerning Example 15 of this invention. FIG. 18 is a diagram illustrating spherical aberration, astigmatism, distortion, and chromatic aberration of magnification when the zoom lens according to Example 15 is focused on an object point at infinity, where (a) is a wide-angle end, (b) is an intermediate position, and (c) Indicates the state at the telephoto end. It is sectional drawing which follows the optical axis which shows the optical structure at the time of infinity object point focusing in the wide angle end of the zoom lens concerning Example 16 of this invention. FIG. 18 is a diagram illustrating spherical aberration, astigmatism, distortion, and lateral chromatic aberration when the zoom lens according to Example 16 is focused on an object point at infinity, where (a) is a wide-angle end, (b) is an intermediate, (c) Indicates the state at the telephoto end. It is sectional drawing which follows the optical axis which shows the optical structure at the time of infinity object point focusing in the wide angle end of the zoom lens concerning Example 17 of this invention. FIG. 18 is a diagram illustrating spherical aberration, astigmatism, distortion, and chromatic aberration of magnification when the zoom lens according to Example 17 is focused on an object point at infinity, where (a) is a wide-angle end, (b) is a middle, (c) Indicates the state at the telephoto end. It is sectional drawing which follows the optical axis which shows the optical structure at the time of infinity object point focusing in the wide angle end of the zoom lens concerning Example 18 of this invention. FIG. 19 is a diagram illustrating spherical aberration, astigmatism, distortion, and chromatic aberration of magnification when the zoom lens according to Example 18 is focused on an object point at infinity, where (a) is a wide-angle end, (b) is an intermediate, and (c) Indicates the state at the telephoto end. It is a front perspective view which shows the external appearance of the digital camera 40 incorporating the zoom optical system by this invention. 2 is a rear perspective view of the digital camera 40. FIG. 2 is a cross-sectional view showing an optical configuration of a digital camera 40. FIG. 1 is a front perspective view of a state in which a cover of a personal computer 300 which is an example of an information processing apparatus in which a zoom optical system of the present invention is built as an objective optical system is opened. FIG. 2 is a cross-sectional view of a photographing optical system 303 of a personal computer 300. FIG. 2 is a side view of a personal computer 300. FIG. 1A and 1B are diagrams showing a mobile phone as an example of an information processing apparatus in which a zoom optical system of the present invention is incorporated as a photographing optical system, in which FIG. 1A is a front view of the mobile phone 400, FIG. FIG. 6 is a cross-sectional view of the photographing optical system 405. It is sectional drawing which follows the optical axis which shows the optical structure at the time of infinity object point focusing in the wide angle end of the zoom lens concerning Example 20 of this invention. FIG. 20 is a diagram illustrating spherical aberration, astigmatism, distortion, and chromatic aberration of magnification when the zoom lens according to Example 20 is focused on an object point at infinity, in which (a) is a wide angle end, (b) is an intermediate, (c) Indicates the state at the telephoto end. It is sectional drawing which follows the optical axis which shows the optical structure at the time of infinity object point focusing in the wide angle end of the zoom lens concerning Example 21 of this invention. FIG. 22 is a diagram illustrating spherical aberration, astigmatism, distortion, and lateral chromatic aberration when the zoom lens according to Example 21 is focused on an object point at infinity, where (a) is a wide-angle end, (b) is a middle, (c) Indicates the state at the telephoto end. It is a figure which shows the relationship between the number of r and d in the numerical data of each Example, and an optical structure (a lens surface, thickness, an air space | interval).

Explanation of symbols

G1 1st lens group G2 2nd lens group G3 3rd lens group G4 4th lens group G5 5th lens group L111-L242 Each lens CG Cover glass I Imaging surface E Eyeball of observer 40 Digital camera 41 Shooting optical system 42 Shooting Optical path 43 Viewfinder optical system 44 Optical path for viewfinder 45 Shutter 46 Flash 47 LCD monitor 49 CCD
DESCRIPTION OF SYMBOLS 50 Image pick-up surface 51 Processing means 53 Finder objective optical system 55 Porro prism 57 Field frame 59 Eyepiece optical system 66 Focusing lens 67 Imaging surface 100 Objective optical system 102 Cover glass 162 Electronic image pick-up element chip | tip 166 Terminal 300 Personal computer 301 Keyboard 302 Monitor 303 Imaging Optical System 304 Imaging Optical Path 305 Image 400 Mobile Phone 401 Microphone Unit 402 Speaker Unit 403 Input Dial 404 Monitor 405 Imaging Optical System 406 Antenna 407 Imaging Optical Path

Claims (10)

An imaging optical system having a plurality of lens groups and changing the interval between adjacent lens groups when zooming,
A first positive lens group, a first negative lens group, a stop, a second positive lens group, and a second negative lens group;
The first positive lens group and the first negative lens group are disposed closer to the object side than the stop,
The second positive lens group and the second negative lens group are disposed on the image side of the stop,
When zooming, the lens group closest to the object side is fixed.
The first positive lens group includes a cemented lens formed by cementing a plurality of lenses;
In a Cartesian coordinate system in which the horizontal axis is Nd and the vertical axis is νd, a straight line represented by Nd = α × νd + β (where α = −0.017) is set.
The area defined by the straight line when the lower limit value is within the range of the conditional expression (1) and the straight line when the upper limit value is satisfied, and the area determined by the following conditional expressions (2) and (3) An imaging optical system including Nd and νd of at least one lens constituting the cemented lens.
1.45 <β <2.15 (1)
1.30 <Nd <2.00 (2)
15 <νd <50 (3)
Here, Nd represents a refractive index and represents an Abbe number.   When one lens in which both Nd and νd are included in both the areas is a predetermined lens, the optical axis center thickness of the predetermined lens is thinner than the optical axis center thickness of the other lenses constituting the cemented lens The imaging optical system according to claim 1. The imaging optical system according to claim 2, wherein the following conditional expression is satisfied.
0.22 <t1 <2.0
However, t1 is the optical axis center thickness of the predetermined lens.   The image forming optical system according to claim 1, wherein the cemented lens is a compound lens obtained by bonding and curing a resin on a lens surface of one lens constituting the cemented lens.   The imaging optical system according to claim 1, wherein the cemented lens is a compound lens formed by closely bonding and curing glass on a lens surface of one lens constituting the cemented lens.   The imaging optical system according to claim 1, wherein the imaging optical system is a zoom lens in which the lens group closest to the object is the first positive lens group.   The imaging optical system according to claim 1, wherein the imaging optical system is a zoom lens in which the lens group closest to the object is the first negative lens group.   The imaging optical system according to claim 1, wherein the imaging optical system includes a prism for bending.   The imaging optical system according to claim 8, wherein the prism is in the lens group closest to the object side. The imaging optical system according to any one of claims 1 to 9, an electronic imaging device, and image data obtained by imaging an image formed through the imaging optical system with the electronic imaging device. Image processing means for processing and outputting as image data in which the shape of the image is changed, and the imaging optical system is a zoom lens, and when the zoom lens is focused on an object point at infinity, the following conditions are satisfied: An electronic imaging apparatus characterized by satisfying the formula:
0.7 <y ₀₇ / (fw · tan ω _07w ) <0.96
However, the table as y ₀₇ = 0.7y ₁₀ when y ₀₇ is obtained by the y ₁₀ distance (maximum image height) to a point farthest from the center in the effective image pickup plane (imaging possible in-plane) of the electronic image pickup device Is done. Further, ω _07w is an angle with respect to the optical axis in the object point direction corresponding to the image point connecting from the center on the imaging surface to the position of y ₀₇ at the wide angle end.

Images