JP4859186B2 - Zoom lens and image pickup apparatus including the same - Google Patents

Description

  The present invention relates to a zoom lens and an image pickup apparatus including the zoom lens, and more particularly to a zoom lens having a refractive power arrangement of negative, positive, positive, negative, positive, or negative and an image pickup apparatus including the zoom lens.

  In recent years, digital still cameras have been downsized and imaging functions have been incorporated into mobile phones, and imaging lenses have been required to be further reduced in size and thickness.

  These photographic lenses are desired to have a zoom magnification in which the zoom ratio from the wide angle end to the telephoto end exceeds 2.5.

  In order to realize such a thin zoom lens, a method of bending the optical axis in the vertical direction using a reflecting member in the zoom lens, or a method of retracting a part of the lens group constituting the zoom lens outside the optical axis Zoom lenses are known.

  However, the method of bending using a reflecting member requires a space for bending the light beam and a space for moving the lens group for securing a zoom ratio. Therefore, these spaces are not lost when the imaging device such as a camera is not used, which is disadvantageous for reducing the volume of the imaging device when not used. Further, the layout in the imaging apparatus is limited by bending the optical axis.

  On the other hand, in the method of retracting a part of the lens group when not in use, a mechanism for retracting the lens group is added. Therefore, it is difficult to suppress the influence when the lens group is decentered with respect to the optical axis. Further, since a retracting drive means for retracting a part of the lens group is required, it is difficult to suppress the volume when not in use, which is disadvantageous in terms of cost.

In addition, as a type of power distribution of each group in a zoom lens that is reduced in size by a normal retractable method,
Negative and positive zoom lens,
Negative, positive, negative type zoom lens,
Negative, positive, positive type zoom lens,
It has been known.

  Among these, the negative and positive type zoom lenses have a small number of lens groups, and are advantageous in reducing the total thickness of the lens frame that directly holds the lenses. However, in order to ensure the zoom ratio, the second lens group is moved to include the region where the same magnification imaging is performed. For this reason, if focusing is performed with the second lens group, a change in the angle of view, a moving amount for focusing, and a change in the moving direction increase, and the second lens group cannot be used for the focusing group. Accordingly, the first lens unit or the entire zoom lens is moved for focusing, which leads to an increase in the total length of the lens frame including the focusing mechanism. As a result, it is disadvantageous for thinning and securing a zoom ratio.

  On the other hand, the negative, positive, and negative type zoom lenses and the negative, positive, and positive type zoom lenses are advantageous in that the increase in the total length can be suppressed by performing focusing with the third lens group.

  In addition, negative, positive, and negative type zoom lenses are advantageous for miniaturization because the front lens diameter can be reduced.

  In addition, negative, positive, and positive type zoom lenses have an advantage that stable optical performance is easily obtained.

  Among zoom lenses of negative, positive, positive or negative, positive and negative types, a type in which the third lens group moves toward the image side at the telephoto end or hardly moves at the telephoto end is generally known. . However, in such a moving system, the position of the third lens group at the telephoto end is close to the image plane, so that the off-axis light beam in the third lens group becomes high, which is disadvantageous for reducing the lens diameter. It becomes. In addition, since the focus sensitivity (the amount of movement of the image plane position when the focus lens moves by the unit movement amount) tends to be low, the third lens group inevitably requires a strong power, and the lens diameter. The lens thickness tends to increase due to the balance between the two.

  Examples of the third lens unit moving to the object side during zooming to the telephoto end are described in Patent Document 1, Patent Document 2, Examples 3 and 4 of Patent Document 3, and Example 2 of Patent Document 4. It has been known.

  However, the zoom lens described in Patent Document 3 is disadvantageous in reducing the thickness in the retracted state because the entire length of the zoom lens is long and the thickness of each lens group is large. In addition, a sufficient focus drive range by moving the third lens group at the telephoto end cannot be secured.

In the zoom lenses described in Patent Document 1, Patent Document 2, and Patent Document 4, the second and third lens groups are moved together during zooming, and the third lens group is moved only during focusing. However, all the lenses have a long overall length, and the thickness of each lens group is large, which is disadvantageous for thinning.
JP 2000-284177 A, JP 2001-242378 A, Japanese Patent No. 3,513,369 Japanese Patent No. 3,606,548

  The present invention has been made in view of such problems in the prior art, and its purpose is to achieve an appropriate zoom ratio without bending the optical axis or retracting some lens groups outside the optical axis. It is possible to provide a zoom lens that can be secured, which is advantageous for ensuring miniaturization and optical performance, and an imaging device using the zoom lens.

The first zoom lens of the present invention includes three lens groups in order from the object side: a first lens group having a negative refractive power, a second lens group having a positive refractive power, and a third lens group having a positive or negative refractive power. A zoom lens in which an interval between the first lens group and the second lens group changes during zooming, and an interval between the second lens group and the third lens group changes during a focusing operation,
At least the second lens group and the third lens group from the wide-angle end to the telephoto end so that the distance between the first lens group and the second lens group becomes narrower in the telephoto end state than in the wide-angle end state. Move only to the object side when scaling to
The second lens group includes a positive lens and a negative lens, is composed of two or three lenses, and is composed of a cemented lens in which each lens is cemented on the optical axis,
The third lens group consists of one lens,
The zoom lens satisfies the following conditional expressions (1), (2) ′, and (A).
0.4 <D _ce / D _123G <0.6 (1)
0.00 ≦ (D ₂ (t) −D ₂ (w)) / f _w <0.5 (2) ′
2.5 ≦ f _t / f _w <5.5 (A)
Where D _ce is the thickness of the cemented lens in the second lens group on the optical axis,
D _123G : Value obtained by adding the thickness on the optical axis of each lens group,
D ₂ (w): an air space on the optical axis between the second lens unit and the third lens unit at the wide-angle end,
D ₂ (t): an air interval on the optical axis between the second lens group and the third lens group at the telephoto end,
f _w : Focal length at the wide-angle end of the zoom lens,
f _t : focal length of the zoom lens in the telephoto end state,
It is.
The second zoom lens according to the present invention includes three lens groups in order from the object side: a first lens group having a negative refractive power, a second lens group having a positive refractive power, and a third lens group having a positive or negative refractive power. A zoom lens in which an interval between the first lens group and the second lens group changes during zooming, and an interval between the second lens group and the third lens group changes during a focusing operation,
At least the second lens group and the third lens group from the wide-angle end to the telephoto end so that the distance between the first lens group and the second lens group becomes narrower in the telephoto end state than in the wide-angle end state. Move only to the object side when scaling to
The second lens group is composed of three lenses of a positive lens, a negative lens, and a positive lens in order from the object side, and a cemented lens in which each lens is cemented on the optical axis.
The third lens group consists of one lens,
The zoom lens satisfies the following conditional expression (1).
0.4 <D _ce / D _123G <0.6 (1)
Where D _ce is the thickness of the cemented lens in the second lens group on the optical axis,
D _123G : Value obtained by adding the thickness on the optical axis of each lens group,
It is.
The third zoom lens of the present invention is composed of three lens groups in order from the object side: a first lens group having a negative refractive power, a second lens group having a positive refractive power, and a third lens group having a positive refractive power, A zoom lens in which an interval between the first lens group and the second lens group changes during zooming, and an interval between the second lens group and the third lens group changes during a focusing operation;
At least the second lens group and the third lens group from the wide-angle end to the telephoto end so that the distance between the first lens group and the second lens group becomes narrower in the telephoto end state than in the wide-angle end state. Move only to the object side when scaling to
The second lens group includes a positive lens and a negative lens, is composed of two or three lenses, and is composed of a cemented lens in which each lens is cemented on the optical axis,
The third lens group is composed of one positive lens,
The third lens group moves for focusing;
This zoom lens satisfies the following conditional expressions (1) and (4).
0.4 <D _ce / D _123G <0.6 (1)
3.0 <f ₃ / f _w <15.0 (4)
Where D _ce is the thickness of the cemented lens in the second lens group on the optical axis,
D _123G : Value obtained by adding the thickness on the optical axis of each lens group,
f ₃ : focal length of the third lens group,
f _w : Focal length at the wide-angle end of the zoom lens,
It is.
The fourth zoom lens of the present invention is composed of three lens groups in order from the object side: a first lens group having a negative refractive power, a second lens group having a positive refractive power, and a third lens group having a positive refractive power, A zoom lens in which an interval between the first lens group and the second lens group changes during zooming, and an interval between the second lens group and the third lens group changes during a focusing operation;
At least the second lens group and the third lens group from the wide-angle end to the telephoto end so that the distance between the first lens group and the second lens group becomes narrower in the telephoto end state than in the wide-angle end state. Move only to the object side when scaling to
The second lens group includes a positive lens and a negative lens, is composed of two or three lenses, and is composed of a cemented lens in which each lens is cemented on the optical axis,
The third lens group is composed of one positive lens,
The zoom lens satisfies the following conditional expressions (1) and (6).
0.4 <D _ce / D _123G <0.6 (1)
0.03 <D _3G / _ft <0.09 (6)
Where D _ce is the thickness of the cemented lens in the second lens group on the optical axis,
D _123G : Value obtained by adding the thickness on the optical axis of each lens group,
D _3G : Thickness on the axis of the third lens group,
f _t : focal length of the zoom lens in the telephoto end state,
It is.
The fifth zoom lens of the present invention is composed of three lens groups in order from the object side: a first lens group having a negative refractive power, a second lens group having a positive refractive power, and a third lens group having a positive refractive power, A zoom lens in which an interval between the first lens group and the second lens group changes during zooming, and an interval between the second lens group and the third lens group changes during a focusing operation;
At least the second lens group and the third lens group from the wide-angle end to the telephoto end so that the distance between the first lens group and the second lens group becomes narrower in the telephoto end state than in the wide-angle end state. Move only to the object side when scaling to
The second lens group includes a positive lens and a negative lens, is composed of two or three lenses, and is composed of a cemented lens in which each lens is cemented on the optical axis,
The third lens group is composed of one positive lens,
The third lens group moves for focusing;
The zoom lens satisfies the following conditional expressions (1) and (B-1).
0.4 <D _ce / D _123G <0.6 (1)
0.35 <1-β _3T ² <0.98 (B-1)
Where D _ce is the thickness of the cemented lens in the second lens group on the optical axis,
D _123G : Value obtained by adding the thickness on the optical axis of each lens group,
β _3T : lateral magnification at the telephoto end of the third lens group,
It is.

  Hereinafter, the reason and action of the above-described configuration in the first to fifth zoom lenses of the present invention will be described.

  Hereinafter, the reason and operation of the zoom lens according to the present invention will be described.

The present invention described above is common, and is composed of three lens groups in order from the object side: a first lens group having a negative refractive power, a second lens group having a positive refractive power, and a third lens group having a positive or negative refractive power. A zoom lens in which an interval between the first lens group and the second lens group changes during zooming, and an interval between the second lens group and the third lens group changes during a focusing operation,
At least the second lens group and the third lens group from the wide-angle end to the telephoto end so that the distance between the first lens group and the second lens group becomes narrower in the telephoto end state than in the wide-angle end state. Move only to the object side when scaling to
The second lens group includes a positive lens and a negative lens, is composed of two or three lenses, and is composed of a cemented lens in which each lens is cemented on the optical axis,
The third lens group consists of one lens,
The above conditional expression (1) is satisfied.

  That is, the third lens group is configured to move to the object side when zooming to the telephoto side. With this configuration, the height of the light beam of the third lens group can be made lower than when the third lens group is fixed or moved to the image side during zooming. Therefore, the diameter of the third lens group can be reduced.

  In particular, since the third lens group is a single lens, the minimum configuration is simple, which is advantageous for downsizing when retracted.

  The second lens group includes a positive lens and a negative lens, and is composed of two or three lenses, and is a cemented lens in which each lens is cemented on the optical axis. As described above, by including the positive lens and the negative lens in the second lens group, it is easy to suppress the occurrence of aberration in the second lens group, but the number of lenses is small. Then, by forming a cemented lens with these lenses, the air gap in the second lens group is eliminated, the second lens group itself is reduced in size, the influence on aberrations due to decentration is reduced, and the third lens group is moved. The configuration is advantageous for securing the range.

  In addition, since the configuration of the second lens group is only a cemented lens, it is only necessary to hold at least one of the lenses in the second lens group, and the thickness of the frame can be reduced. It is advantageous for thinning.

And the above-mentioned conditional expression (1) is satisfied. In order to improve the yield during production while ensuring the thinning when retracted, the ratio of the thickness of the cemented lens in the second lens group to the value D _{123G obtained} by adding the thickness on the optical axis of each group Is preferably in the range of the conditional expression (1).

  In order to obtain an essentially good field curvature aberration, it is common to reduce the difference between the sagittal image plane and the meridional image plane by increasing the total thickness of the second lens group. In general, the spherical lens aberration is mainly corrected on the object side surface and the curvature of field aberration is mainly corrected on the image side surface by securing the configuration length of the second lens group. However, if the total length of the second lens group is increased, it becomes difficult to make the system compact when the entire system is retracted.

  On the other hand, by devising the shape and material of each lens in the second lens group to balance aberrations, it is possible to reduce the configuration length of the second lens group while maintaining the design performance. However, in that case, the influence on the optical performance due to errors in shape and thickness becomes sensitive. For this reason, the allowable range of manufacturing error is reduced.

  Conditional expression (1) is a condition for reducing the configuration length of the second lens group while ensuring an acceptable range of manufacturing errors that is substantially satisfactory. If the lower limit of 0.4 is not reached, the thickness of the cemented lens becomes small, and the manufacturing error of the thickness affects the spherical aberration and the curvature of field, making it difficult to maintain the optical performance. When the value exceeds the upper limit of 0.6, the thickness of the second lens unit becomes too large with respect to the thickness of the entire system, and it is difficult to reduce the thickness when retracted.

  It is more preferable that the third lens group is composed of a plastic single lens to reduce the weight.

  It is preferable to perform focusing by moving only the third lens group. In the present invention, the third lens group is located closer to the object side as the telephoto side is closer. In this case, the focus sensitivity in the third lens group becomes high, and the power of the third lens group can be relaxed. Therefore, the thickness of the third lens group can be reduced, which is advantageous for reducing the thickness when the lens barrel is retracted.

  Further, when the third lens group is a focus group, the third lens group is only one lens, and the weight of the lens can be suppressed, so that the drive system can be simplified and the lens frame can be made smaller. Contribute.

  Further, if the distance between the second lens group and the third lens group changes during zooming, it is effective for adjusting the image position during zooming and for suppressing aberration fluctuations due to zooming.

  Further, by adopting a configuration in which the first lens group reciprocates during zooming, the first lens group can have a main image position adjustment function.

  Also, when the distance between the second and third lens groups changes during zooming, aberrations due to zooming can be suppressed by adjusting the amount of movement.

  In addition, it is preferable that the first lens group includes a negative lens and a positive lens in order from the object side.

  With such a configuration, it is possible to easily balance aberration such as chromatic aberration while reducing the size of the first lens group closer to the object side in use. Further, it is effective for both maintaining optical performance and making the lens frame thinner when retracted.

  Moreover, it is preferable that the following conditional expression (2) is satisfied.

−0.005 <(D ₂ (t) −D ₂ (w)) / f _w <0.5 (2)
Where D ₂ (w): the air spacing on the optical axis between the second lens group and the third lens group at the wide-angle end,
D ₂ (t): an air interval on the optical axis between the second lens group and the third lens group at the telephoto end,
f _w : Focal length at the wide-angle end of the zoom lens,
It is.

  Conditional expression (2) defines the difference between the second and third lens groups at the telephoto end and the wide-angle end in terms of the focal length at the wide-angle end, and achieves both ease of image position correction and downsizing. Is a conditional expression. If it does not fall below the lower limit of -0.005 of this conditional expression, it becomes easy to secure the interval necessary for adjusting the image plane position deviation by adjusting the position of the third lens group. In addition, when focusing is performed with the third lens group, it is easy to secure an interval necessary for focusing at the telephoto end. Further, if the upper limit of 0.5 is not exceeded, the light ray height of the first lens group at the wide-angle end is suppressed from increasing, and the increase in the front lens diameter is easily suppressed. Alternatively, it is possible to suppress an increase in the off-axis ray height of the third lens group that is the final lens at the telephoto end, which is advantageous in reducing the lens diameter.

  In addition, when the holding frame that holds the third lens group is held upright from the holding frame of the second lens group, the length of the axis becomes longer according to the amount of movement of the third lens group. Therefore, by satisfying conditional expression (2), it is possible to easily reduce the thickness when retracted.

  In addition, it is preferable that the second lens group includes a single cemented lens including three lenses of a positive lens, a negative lens, and a positive lens in order from the object side.

  With this configuration, the second lens group is composed of one cemented lens, while the three lenses of the positive lens, the negative lens, and the positive lens are easily suppressed from generating aberrations in the second lens group. Thus, the second lens group itself is advantageous in size reduction and in securing the movement range of the third lens group.

  Furthermore, the incident side surface of the cemented lens has a shape having a positive refractive power on the optical axis and a refractive power that decreases as the distance from the optical axis increases, thereby ensuring the positive refractive power of the second lens group. While securing a zoom ratio by being closer to the object side, it is advantageous for correcting spherical aberration that is likely to occur on this surface.

  In addition, the exit side surface of the cemented lens has a shape in which the refractive power decreases toward the periphery (the positive refractive power decreases or the negative refractive power increases), which is advantageous for correcting curvature of field.

  Further, if the Abbe number of the negative lens in the cemented lens is smaller than the Abbe number of any positive lens in the cemented lens, and the cemented surface is a concave surface of the negative lens, the cemented surface has a negative refractive power. Correction of chromatic aberration can be performed satisfactorily.

  In other words, spherical aberration is mainly caused by the object-side lens surface of the cemented lens, chromatic aberration is mainly controlled by the power and Abbe number rather than the surface shape of the negative lens in the middle, and mainly off-axis by the lens surface on the image side. Aberration control can be realized. Although it is not main, naturally there is also an effect of aberration control at the joint surface, so it is preferable to use it together with the main effect.

  Moreover, it is preferable to set it as the structure which satisfies the following conditional expressions (3).

1.2 <C _j (t) / _ft <1.8 (3)
Where C _j (t): distance from the entrance surface of the first lens group to the image plane at the telephoto end,
f _t : Focal length at the telephoto end of the zoom lens,
It is.

  Conditional expression (3) defines the total length of the zoom lens at the telephoto end by the focal length of the telephoto end, and is a condition for enabling the configuration of the lens barrel to be simplified by shortening the total length. If the lower limit of 1.2 of conditional expression (3) is not exceeded, an increase in the total length in the wide-angle end state can be easily suppressed. Alternatively, it is easy to obtain a desired zoom ratio. If the upper limit of 1.8 is exceeded, the entire length of the lens frame can be easily suppressed, which is advantageous for downsizing.

  In addition, it is preferable that the third lens group moves for focusing and the third lens group is a positive lens that satisfies the following conditional expression (4).

3.0 <f ₃ / f _w <15.0 (4)
Where f _{3 is} the focal length of the third lens group,
f _w : Focal length at the wide-angle end of the zoom lens,
It is.

  Conditional expression (4) defines the focal length of the third lens group in terms of the focal length at the wide-angle end of the zoom lens. In the present invention, the third lens unit is advantageously reduced in size by the moving method of the third lens unit. In particular, when the third lens group is a focus lens group, the burden on the drive mechanism can be reduced compared to other focusing methods. In the present invention, since the focus sensitivity of the third lens group at the telephoto end is easily increased, the refractive power of the third lens group can be appropriately reduced so as to satisfy the conditional expression (4). It will be advantageous.

  If it does not fall below 3.0, which is the lower limit of conditional expression (4), it is easy to suppress the light beam height at the first lens group at the wide angle end, and the front lens diameter (first lens group) can be easily reduced. Alternatively, the influence of the aberration in the third lens group is suppressed, the increase in the thickness of the third lens group is suppressed, which is advantageous for thinning the lens frame. If the upper limit of 15.0 in the conditional expression (4) is not exceeded, the amount of movement of the third lens unit during focusing is suppressed, which is advantageous for thinning.

  Further, it is preferable that the third lens group is moved for focusing and the third lens group is a negative lens that satisfies the following conditional expression (5).

1.5 <| f ₃ / f _w | <15.0 (5)
Where f _{3 is} the focal length of the third lens group,
f _w : Focal length at the wide-angle end of the zoom lens,
It is.

  Conditional expression (5) defines the focal length of the third lens group in terms of the focal length at the wide-angle end of the zoom lens. In the present invention, the third lens unit is advantageously reduced in size by the moving method of the third lens unit. In particular, if the third lens group is a negative lens, it is advantageous for reducing the size of the optical system in the radial direction. When the third lens group is a focus lens group, the focus sensitivity of the third lens group at the telephoto end is easily increased, so that the refractive power of the third lens group satisfies the conditional expression (5). It can be made reasonably small, which is advantageous for further downsizing.

  If the lower limit of 1.5 of conditional expression (5) is not exceeded, the refractive power in the third lens group can be suppressed, and the influence on aberration can be easily reduced. Further, an increase in the thickness of the edge of the third lens group is suppressed, which is advantageous for making the lens frame thinner. If the upper limit of 15.0 in conditional expression (5) is not exceeded, the amount of movement of the third lens unit during focusing is suppressed, which is advantageous for thinning.

  Further, it is preferable that the following conditional expression (6) is satisfied so that the third lens group becomes a thick positive lens having an appropriate thickness.

0.03 <D _3G / _ft <0.09 (6)
D _3G : Thickness on the axis of the third lens group,
f _t : focal length of the zoom lens in the telephoto end state,
It is.

  By making sure that the lower limit of 0.03 of conditional expression (6) is not exceeded, it is advantageous for securing positive refractive power necessary for the third lens group. By preventing the upper limit of 0.09 of conditional expression (6) from being exceeded, the axial thickness of the third lens group is suppressed, which is advantageous for downsizing the zoom lens when retracted.

  Further, it is preferable that the following conditional expression (7) is satisfied so that the third lens group becomes a moderately thick negative lens.

0.01 <D _3G / _ft <0.09 (7)
D _3G : Thickness on the axis of the third lens group,
f _t : focal length of the zoom lens in the telephoto end state,
It is.

  By making sure that the lower limit of 0.01 of the conditional expression (7) is not exceeded, it is advantageous for securing the strength of the negative lens necessary for the third lens group. By preventing the upper limit of 0.09 of conditional expression (7) from being exceeded, the axial thickness of the third lens group is suppressed, which is advantageous for downsizing the zoom lens when retracted.

  When focusing is performed by moving the third lens group, the focus sensitivity of the third lens group depends on the magnification of the third lens group. Therefore, when the third lens group is a positive lens, it is preferable that the following conditional expression (B-1) is satisfied so that the focus sensitivity of the third lens group at the telephoto end becomes appropriate.

0.35 <1-β _3T ² <0.98 (B-1)
Where β _3T : lateral magnification at the telephoto end of the third lens group,
It is.

  If the lower limit of 0.35 in conditional expression (B-1) is not exceeded, the amount of movement of the third lens group can be suppressed, or an increase in the space for the focus operation can be suppressed, and the zoom lens in use. This is advantageous for overall miniaturization. If the upper limit of 0.98 in conditional expression (B-1) is not exceeded, the lateral magnification in the third lens group can be kept small, which is advantageous in reducing the distance to the image plane and reducing the size. Become.

  When the third lens group is a negative lens, it is preferable that the following conditional expression (B-2) is satisfied so that the focus sensitivity of the third lens group at the telephoto end becomes appropriate.

−3.5 <1-β _3T ² <−0.6 (B-2)
Where β _3T : lateral magnification at the telephoto end of the third lens group,
It is.

  If the lower limit of −3.5 of conditional expression (B-2) is not reduced, the absolute value of the lateral magnification in the third lens group can be kept small, so that the focus sensitivity is prevented from becoming too high, and focusing is prevented. This is advantageous for ensuring accuracy. If the upper limit of -0.6 of conditional expression (B-2) is not exceeded, focus sensitivity can be ensured, so that the movement range for the focus operation can be suppressed, which is advantageous for downsizing the drive mechanism.

  Moreover, it is preferable to set it as the structure which satisfies the following conditional expressions (A).

2.5 ≦ f _t / f _w <5.5 (A)
Where f _t : focal length of the zoom lens in the telephoto end state,
f _w : Focal length at the wide-angle end of the zoom lens,
It is.

  This conditional expression (A) defines the zoom ratio of the zoom lens. The present invention is preferably a zoom lens having an appropriate zoom ratio of 2.5 or more, since it is easy to balance the size of the entire system and the optical performance. If the lower limit of 2.5 of the conditional expression (A) is not exceeded, the zoom ratio in general use is satisfied. If the upper limit of 5.5 of the conditional expression (A) is not exceeded, it is advantageous for cost reduction, such as suppressing an increase in the number of lenses for correcting aberrations.

  In addition, it is preferable to have a configuration including an aperture stop that is disposed immediately before the second lens group and moves integrally with the second lens group at the time of zooming.

  With such a configuration, an increase in the diameter of the first lens group can be prevented, and the off-axis principal ray emitted from the third lens group can be easily made parallel to the optical axis. In addition, since there is no second lens group on the object side of the aperture stop and the lenses of the second lens group are concentrated on the image side of the aperture stop, aberration deterioration due to relative decentration of the lenses in the second lens group is also caused. It can be configured to be suppressed. Also, the movement mechanism of the aperture stop can be shared with the second lens group, and the configuration can be simplified easily.

  It is preferable that the zoom lens according to any one of the present invention described above and an image sensor that is disposed on the image side and converts an optical image into an electric signal are provided.

  The zoom lens of the present invention is advantageous for downsizing and securing a field angle at the wide-angle end. In addition, since it is easy to suppress the incident angle of light rays to the imaging surface and the influence of color shading can be reduced, it is preferable to use the imaging device including the above-described imaging device.

  Each of the above-described configurations may arbitrarily satisfy a plurality at the same time, whereby a better effect can be obtained.

  Moreover, it is good also as a structure which made the structural requirement described dependent on a specific structure dependent on another structure.

  Further, if each conditional expression is satisfied by being arbitrarily combined, a better effect can be obtained.

Moreover, in order to make the above-mentioned effect more favorable, it is preferable to adopt the following configuration for each conditional expression.
In the conditional expression (1), in order to make the balance between the influence of the manufacturing error and the configuration length of the second lens group better, it is more preferable that the lower limit value is 0.46, and further 0.48.

  Further, it is more preferable that the upper limit value is 0.55, further 0.52.

  For conditional expression (2), it is more preferable to set the lower limit to 0.01, and further to 0.03.

  Further, it is more preferable that the upper limit value is 0.4, further 0.35.

  Regarding conditional expression (3), when the third lens group is a positive lens, it is more preferable to set the lower limit value to 1.4 and even 1.5 for the balance between aberration balance and overall length reduction.

  Further, it is more preferable that the upper limit value is 1.76, and further 1.7.

  In the case where the third lens group is a negative lens, it is more preferable that the lower limit value is 1.3, and further 1.35 in order to balance the aberration balance and the shortening of the total length.

  Further, it is more preferable that the upper limit value is 1.7, further 1.5.

  For conditional expression (4), it is more preferable to set the lower limit to 3.4.

  It is more preferable that the upper limit value is 10.0, further 8.0.

  For conditional expression (5), it is more preferable that the lower limit value be 1.8, and further 2.0.

  Further, it is more preferable that the upper limit value is 10.0, further 7.0.

  For conditional expression (6), it is more preferable to set the lower limit to 0.04, and more preferably 0.05.

  Further, the upper limit value is more preferably 0.084, and further preferably 0.077.

  In conditional expression (7), it is more preferable that the lower limit value be 0.02, and further 0.03.

  Further, it is more preferable that the upper limit value is 0.07, further 0.055.

  For conditional expression (A), it is more preferable to set the lower limit to 2.6, and even 2.7.

  Further, it is more preferable that the upper limit value is 4.5, further 3.5.

  According to the present invention as described above, it is possible to secure an appropriate zoom ratio without bending the optical axis or retracting a part of the lens group to the outside of the optical axis, and it is advantageous for downsizing and ensuring optical performance. An imaging device using can be obtained.

  Examples 1 to 17 of the zoom lens according to the present invention will be described below. FIGS. 1 to 17 show lens cross-sectional views of the wide-angle end (a), the intermediate state (b), and the telephoto end (c) when focusing on an object point at infinity in Examples 1 to 17, respectively. In the figure, the first lens group is G1, the aperture stop is S, the second lens group is G2, the third lens group is G3, the parallel plate constituting the low-pass filter with IR cut coating, etc. is F, the electronic imaging element ( The parallel plate of the cover glass of CCD or CMOS) is indicated by C, and the image plane (light receiving surface of the electronic image sensor) is indicated by I. In addition, a multilayer film for limiting the wavelength region may be provided on the surface of the cover glass G. Further, the cover glass G may have a low-pass filter function.

  As shown in FIG. 1, the zoom optical system according to the first exemplary embodiment includes, in order from the object side, a first lens group G1 having a negative refractive power, an aperture stop S, a second lens group G2 having a positive refractive power, and a first lens group having a negative refractive power. The first lens group G1 moves to the image side when zooming from the wide-angle end to the telephoto end. The aperture stop S and the second lens group G2 move monotonously toward the object side while integrally reducing the distance between the first lens group G1. The third lens group G3 moves toward the object side while widening the distance from the second lens group G2.

  In order from the object side, the first lens group G1 includes a negative meniscus lens having a convex surface directed toward the object side and a positive meniscus lens having a convex surface directed toward the object side. The second lens group G2 includes a biconvex positive lens and an image. The third lens group G3 is composed of one biconcave negative lens. The third lens group G3 is composed of a cemented triplet of a negative meniscus lens having a convex surface on the side and a positive meniscus lens having a convex surface on the image side. The aperture stop S is positioned on the image side of the most object side surface of the three-piece cemented lens of the second lens group G2.

  The aspheric surfaces are the surfaces of the positive meniscus lens of the first lens group G1, the most object side surface and the image side surface of the triplet cemented lens of the second lens group G2, and the biconcave negative lens of the third lens group G3. Used on 6 sides.

  As shown in FIG. 2, the zoom optical system according to the second embodiment includes, in order from the object side, a first lens group G1 having a negative refractive power, an aperture stop S, a second lens group G2 having a positive refractive power, and a first lens group having a negative refractive power. The first lens group G1 moves in a concave locus on the object side when zooming from the wide-angle end to the telephoto end, and at the telephoto end from the position of the wide-angle end. Located on the image side. The aperture stop S and the second lens group G2 move monotonously toward the object side while integrally reducing the distance between the first lens group G1. The third lens group G3 moves toward the object side while widening the distance from the second lens group G2.

  In order from the object side, the first lens group G1 includes a biconcave negative lens and a positive meniscus lens having a convex surface facing the object side, and the second lens group G2 has a convex surface facing the biconvex positive lens and the image side. The third lens group G3 is composed of a single negative meniscus lens having a convex surface on the image side. The aperture stop S is located on the image side of the most object side surface of the two-junction lens of the second lens group G2.

  The aspheric surfaces are used for the three surfaces of the image side surface of the biconcave negative lens of the first lens group G1, and the most object side surface and the most image side surface of the two-junction lens of the second lens group G2.

  As shown in FIG. 3, the zoom optical system according to the third embodiment includes, in order from the object side, a first lens group G1 having a negative refractive power, an aperture stop S, a second lens group G2 having a positive refractive power, and a first lens group having a negative refractive power. The first lens group G1 moves in a concave locus on the object side when zooming from the wide-angle end to the telephoto end, and at the telephoto end from the position of the wide-angle end. Located on the image side. The aperture stop S and the second lens group G2 move monotonously toward the object side while integrally reducing the distance between the first lens group G1. The third lens group G3 moves toward the object side while widening the distance from the second lens group G2.

  In order from the object side, the first lens group G1 includes a negative meniscus lens having a convex surface directed toward the object side and a positive meniscus lens having a convex surface directed toward the object side. The second lens group G2 includes a biconvex positive lens and an image. The third lens group G3 is composed of one biconcave negative lens. The third lens group G3 is composed of a cemented triplet of a negative meniscus lens having a convex surface on the side and a positive meniscus lens having a convex surface on the image side. The aperture stop S is located at the same position as the most object side surface of the three-junction lens of the second lens group G2.

  The aspherical surfaces are the image side surface of the negative meniscus lens of the first lens group G1, the most object side surface and the most image side surface of the triplet cemented lens of the second lens group G2, and the biconcave of the third lens group G3. It is used for 5 surfaces on both sides of the negative lens.

  As shown in FIG. 4, the zoom optical system according to the fourth embodiment includes, in order from the object side, a first lens group G1 having a negative refractive power, an aperture stop S, a second lens group G2 having a positive refractive power, and a first lens group having a negative refractive power. The first lens group G1 moves in a concave locus on the object side when zooming from the wide-angle end to the telephoto end, and at the telephoto end from the position of the wide-angle end. Located on the image side. The aperture stop S and the second lens group G2 move monotonously toward the object side while integrally reducing the distance between the first lens group G1. The third lens group G3 moves toward the object side while widening the distance from the second lens group G2.

  In order from the object side, the first lens group G1 includes a biconcave negative lens and a positive meniscus lens having a convex surface directed toward the object side. The second lens group G2 includes a biconvex positive lens, a biconcave negative lens, and a biconvex lens. The third lens group G3 is composed of a single biconcave negative lens. The aperture stop S is positioned on the image side of the most object side surface of the three-piece cemented lens of the second lens group G2.

  The aspherical surfaces are the object side surface of the positive meniscus lens of the first lens group G1, the most object side surface and the most image side surface of the three-piece cemented lens of the second lens group G2, and the biconcave of the third lens group G3. It is used for 5 surfaces on both sides of the negative lens.

  As shown in FIG. 5, the zoom optical system according to the fifth embodiment includes, in order from the object side, a first lens unit G1 having a negative refractive power, an aperture stop S, a second lens unit G2 having a positive refractive power, and a first lens unit having a negative refractive power. The first lens group G1 moves to the image side when zooming from the wide-angle end to the telephoto end. The aperture stop S and the second lens group G2 move monotonously toward the object side while integrally reducing the distance between the first lens group G1. The third lens group G3 moves to the object side while temporarily shortening and then widening the distance from the second lens group G2.

  In order from the object side, the first lens group G1 includes a biconcave negative lens and a positive meniscus lens having a convex surface facing the object side, and the second lens group G2 has a convex surface facing the biconvex positive lens and the image side. The third lens group G3 includes one biconcave negative lens. The third lens group G3 includes a negative meniscus lens and a negative meniscus lens having a convex surface facing the image side. The aperture stop S is positioned on the image side of the most object side surface of the three-piece cemented lens of the second lens group G2.

  The aspheric surfaces are the surfaces of the positive meniscus lens of the first lens group G1, the most object side surface and the image side surface of the triplet cemented lens of the second lens group G2, and the biconcave negative lens of the third lens group G3. Used on 6 sides.

  As shown in FIG. 6, the zoom optical system according to the sixth embodiment includes, in order from the object side, a first lens group G1 having a negative refractive power, an aperture stop S, a second lens group G2 having a positive refractive power, and a first lens group having a negative refractive power. The first lens group G1 moves to the image side when zooming from the wide-angle end to the telephoto end. The aperture stop S and the second lens group G2 move monotonously toward the object side while integrally reducing the distance between the first lens group G1. The third lens group G3 moves to the object side while once increasing the distance from the second lens group G2 and then reducing it.

  In order from the object side, the first lens group G1 includes a biconcave negative lens and a positive meniscus lens having a convex surface facing the object side, and the second lens group G2 has a convex surface facing the biconvex positive lens and the image side. The third lens group G3 is composed of one biconcave negative lens. The third lens group G3 is composed of a cemented lens composed of a negative meniscus lens and a biconcave negative lens. The aperture stop S is positioned on the image side of the most object side surface of the three-piece cemented lens of the second lens group G2.

  The aspherical surfaces are the image side surface of the biconcave negative lens of the first lens group G1, the most object side surface and the most image side surface of the three-piece cemented lens of the second lens group G2, and both of the third lens group G3. It is used for 5 surfaces on both sides of the concave negative lens.

  As shown in FIG. 7, the zoom optical system according to the seventh embodiment includes, in order from the object side, a first lens group G1 having a negative refractive power, an aperture stop S, a second lens group G2 having a positive refractive power, and a first lens group having a negative refractive power. Consists of three lens groups G3, and when zooming from the wide-angle end to the telephoto end, the first lens group G1 moves with a concave locus on the object side, and at the telephoto end, the object is slightly more intermediate than in the intermediate state. It is located on the image side from the wide-angle end position. The aperture stop S and the second lens group G2 move monotonously toward the object side while integrally reducing the distance between the first lens group G1. The third lens group G3 moves to the object side while temporarily shortening and then widening the distance from the second lens group G2.

  In order from the object side, the first lens group G1 includes a biconcave negative lens and a positive meniscus lens having a convex surface directed toward the object side, and the second lens group G2 includes a positive meniscus lens having a convex surface directed toward the object side and an object. The third lens group G3 is composed of one biconcave negative lens. The third lens group G3 is composed of a cemented three-lens lens composed of a negative meniscus lens having a convex surface facing the side and a biconvex positive lens. The aperture stop S is positioned on the image side of the most object side surface of the three-piece cemented lens of the second lens group G2.

  The aspherical surfaces are the image side surface of the biconcave negative lens of the first lens group G1, the most object side surface and the most image side surface of the three-piece cemented lens of the second lens group G2, and both of the third lens group G3. It is used for 5 surfaces on both sides of the concave negative lens.

  As shown in FIG. 8, the zoom optical system according to the eighth embodiment includes, in order from the object side, a first lens group G1 having a negative refractive power, an aperture stop S, a second lens group G2 having a positive refractive power, and a first lens group having a positive refractive power. The first lens group G1 moves in a concave locus on the object side when zooming from the wide-angle end to the telephoto end, and at the telephoto end is closer to the image side than the wide-angle end. Located in. The aperture stop S and the second lens group G2 move monotonously toward the object side while integrally reducing the distance between the first lens group G1. The third lens group G3 moves toward the object side while widening the distance from the second lens group G2.

  In order from the object side, the first lens group G1 includes a negative meniscus lens having a convex surface facing the object side and a positive meniscus lens having a convex surface facing the object side. The second lens group G2 has a convex surface facing the object side. A positive meniscus lens, a negative meniscus lens having a convex surface facing the object side, and a positive meniscus lens having a convex surface facing the object side. The third lens group G3 includes one biconvex positive lens. . The aperture stop S is positioned on the image side of the most object side surface of the three-piece cemented lens of the second lens group G2.

  The aspherical surfaces are the image side surface of the negative meniscus lens of the first lens group G1, the most object side surface and the most image side surface of the triplet cemented lens of the second lens group G2, and the biconvex shape of the third lens group G3. The positive lens is used for four surfaces on the object side.

  As shown in FIG. 9, the zoom optical system according to the ninth embodiment includes, in order from the object side, a first lens group G1 having a negative refractive power, an aperture stop S, a second lens group G2 having a positive refractive power, and a first lens group having a positive refractive power. The first lens group G1 moves in a concave locus on the object side when zooming from the wide-angle end to the telephoto end, and at the telephoto end is closer to the image side than the wide-angle end. Located in. The aperture stop S and the second lens group G2 move monotonously toward the object side while integrally reducing the distance between the first lens group G1. The third lens group G3 moves toward the object side while widening the distance from the second lens group G2.

  In order from the object side, the first lens group G1 includes a biconcave negative lens and a positive meniscus lens having a convex surface directed toward the object side, and the second lens group G2 includes a positive meniscus lens having a convex surface directed toward the object side and an object. The third lens group G3 is composed of one positive meniscus lens having a convex surface facing the object side and a negative meniscus lens having a convex surface facing the object side, and a positive meniscus lens having a convex surface facing the object side. . The aperture stop S is positioned on the image side of the most object side surface of the three-piece cemented lens of the second lens group G2.

  The aspheric surfaces are the image side surface of the biconcave negative lens of the first lens group G1, the most object side surface and the most image side surface of the three-junction lens of the second lens group G2, and the positive surface of the third lens group G3. It is used for four surfaces on the object side of the meniscus lens.

  As shown in FIG. 10, the zoom optical system according to the tenth embodiment includes, in order from the object side, a first lens group G1 having a negative refractive power, an aperture stop S, a second lens group G2 having a positive refractive power, and a first lens group having a positive refractive power. The first lens group G1 moves in a concave locus on the object side when zooming from the wide-angle end to the telephoto end, and at the telephoto end is closer to the image side than the wide-angle end. Located in. The aperture stop S and the second lens group G2 move monotonously toward the object side while integrally reducing the distance between the first lens group G1. The third lens group G3 moves toward the object side while widening the distance from the second lens group G2.

  In order from the object side, the first lens group G1 includes a biconcave negative lens and a positive meniscus lens having a convex surface directed toward the object side, and the second lens group G2 includes a positive meniscus lens having a convex surface directed toward the object side and an object. The third lens group G3 is composed of one positive meniscus lens having a convex surface facing the object side and a negative meniscus lens having a convex surface facing the object side, and a positive meniscus lens having a convex surface facing the object side. . The aperture stop S is positioned on the image side of the most object side surface of the three-piece cemented lens of the second lens group G2.

  The aspheric surfaces are the image side surface of the biconcave negative lens of the first lens group G1, the most object side surface and the most image side surface of the three-junction lens of the second lens group G2, and the positive surface of the third lens group G3. It is used for four surfaces on the object side of the meniscus lens.

  As shown in FIG. 11, the zoom optical system according to the eleventh embodiment includes, in order from the object side, a first lens group G1 having a negative refractive power, an aperture stop S, a second lens group G2 having a positive refractive power, and a first lens group having a positive refractive power. Consists of three lens groups G3, and when zooming from the wide-angle end to the telephoto end, the first lens group G1 moves with a concave locus on the object side, and at the telephoto end, the object is slightly more intermediate than in the intermediate state. It is located on the image side from the wide-angle end position. The aperture stop S and the second lens group G2 move monotonously toward the object side while integrally reducing the distance between the first lens group G1. The third lens group G3 moves to the object side while once increasing the distance from the second lens group G2 and then reducing it.

  In order from the object side, the first lens group G1 includes a negative meniscus lens having a convex surface facing the object side and a positive meniscus lens having a convex surface facing the object side. The second lens group G2 has a convex surface facing the object side. A positive meniscus lens, a negative meniscus lens having a convex surface facing the object side, and a positive meniscus lens having a convex surface facing the object side. The third lens group G3 includes one biconvex positive lens. . The aperture stop S is positioned on the image side of the most object side surface of the three-piece cemented lens of the second lens group G2.

  The aspheric surfaces are the image side surface of the negative meniscus lens and the object side surface of the positive meniscus lens of the first lens group G1, and the most object side surface and the most image side surface of the three-junction lens of the second lens group G2. And 6 surfaces on both sides of the biconvex positive lens of the third lens group G3.

  As shown in FIG. 12, the zoom optical system according to the twelfth embodiment includes, in order from the object side, a first lens group G1 having a negative refractive power, an aperture stop S, a second lens group G2 having a positive refractive power, and a first lens group having a positive refractive power. The first lens group G1 moves in a concave locus on the object side when zooming from the wide-angle end to the telephoto end, and at the telephoto end is closer to the image side than the wide-angle end. Located in. The aperture stop S and the second lens group G2 move monotonously toward the object side while integrally reducing the distance between the first lens group G1. The third lens group G3 moves toward the object side while widening the distance from the second lens group G2.

  In order from the object side, the first lens group G1 includes a biconcave negative lens and a positive meniscus lens having a convex surface facing the object side. The second lens group G2 includes a biconvex positive lens, a biconcave negative lens, and an object side. The third lens group G3 is composed of one positive meniscus lens having a convex surface facing the object side. The aperture stop S is positioned on the image side of the most object side surface of the three-piece cemented lens of the second lens group G2.

  The aspherical surfaces are used for the image side surface of the biconcave negative lens of the first lens group G1, and the most object side surface and the most image side surface of the three-junction lens of the second lens group G2.

  As shown in FIG. 13, the zoom optical system according to the thirteenth embodiment includes, in order from the object side, a first lens unit G1 having a negative refractive power, an aperture stop S, a second lens unit G2 having a positive refractive power, and a first lens unit having a positive refractive power. The first lens group G1 moves in a concave locus on the object side when zooming from the wide-angle end to the telephoto end, and at the telephoto end is closer to the image side than the wide-angle end. Located in. The aperture stop S and the second lens group G2 move monotonously toward the object side while integrally reducing the distance between the first lens group G1. The third lens group G3 moves toward the object side while widening the distance from the second lens group G2.

  In order from the object side, the first lens group G1 includes a biconcave negative lens and a positive meniscus lens having a convex surface facing the object side. The second lens group G2 includes a biconvex positive lens, a biconcave negative lens, and an object side. The third lens group G3 is composed of one positive meniscus lens having a convex surface facing the object side. The aperture stop S is positioned on the image side of the most object side surface of the three-piece cemented lens of the second lens group G2.

  The aspherical surfaces are used for the image side surface of the biconcave negative lens of the first lens group G1, and the most object side surface and the most image side surface of the three-junction lens of the second lens group G2.

  As shown in FIG. 14, the zoom optical system according to the fourteenth embodiment includes, in order from the object side, a first lens unit G1 having a negative refractive power, an aperture stop S, a second lens unit G2 having a positive refractive power, and a first lens unit having a positive refractive power. The first lens group G1 moves in a concave locus on the object side when zooming from the wide-angle end to the telephoto end, and at the telephoto end is closer to the image side than the wide-angle end. Located in. The aperture stop S and the second lens group G2 move monotonously toward the object side while integrally reducing the distance between the first lens group G1. The third lens group G3 moves toward the object side while slightly increasing the distance from the second lens group G2 and then slightly reducing it.

  In order from the object side, the first lens group G1 includes a negative meniscus lens having a convex surface facing the object side and a positive meniscus lens having a convex surface facing the object side. The second lens group G2 has a convex surface facing the object side. The third lens group G3 is composed of a single positive meniscus lens having a convex surface facing the object side, and a positive meniscus lens having a convex surface facing the object side and a bi-convex positive lens. . The aperture stop S is positioned on the image side of the most object side surface of the three-piece cemented lens of the second lens group G2.

  The aspherical surfaces are used on both surfaces of the positive meniscus lens of the first lens group G1, and on the four surfaces of the most cemented lens in the second lens group G2, the most object side surface and the most image side surface.

  As shown in FIG. 15, the zoom optical system according to the fifteenth embodiment includes, in order from the object side, a first lens unit G1 having a negative refractive power, an aperture stop S, a second lens unit G2 having a positive refractive power, and a first lens unit having a positive refractive power. Consists of three lens groups G3, and when zooming from the wide-angle end to the telephoto end, the first lens group G1 moves with a concave locus on the object side, and at the telephoto end, the object is slightly more intermediate than in the intermediate state. It is located on the image side from the wide-angle end position. The aperture stop S and the second lens group G2 move monotonously toward the object side while integrally reducing the distance between the first lens group G1. The third lens group G3 moves to the object side while once increasing the distance from the second lens group G2 and then reducing it.

  In order from the object side, the first lens group G1 includes a negative meniscus lens having a convex surface facing the object side and a positive meniscus lens having a convex surface facing the object side. The second lens group G2 has a convex surface facing the object side. The third lens group G3 is composed of a positive meniscus lens, a negative meniscus lens having a convex surface facing the object side, and a positive meniscus lens having a convex surface facing the object side. Consists of a single meniscus lens. The aperture stop S is positioned on the image side of the most object side surface of the three-piece cemented lens of the second lens group G2.

  The aspheric surfaces are both surfaces of the positive meniscus lens of the first lens group G1, the most object side surface and the most image side surface of the triplet cemented lens of the second lens group G2, and both surfaces of the positive meniscus lens of the third lens group G3. It is used for 6 sides.

  As shown in FIG. 16, the zoom optical system of Example 16 has, in order from the object side, a first lens unit G1 having a negative refractive power, an aperture stop S, a second lens unit G2 having a positive refractive power, and a first lens unit having a positive refractive power. The first lens group G1 moves in a concave locus on the object side when zooming from the wide-angle end to the telephoto end, and at the telephoto end is closer to the image side than the wide-angle end. Located in. The aperture stop S and the second lens group G2 move monotonously toward the object side while integrally reducing the distance between the first lens group G1. The third lens group G3 moves to the object side while temporarily shortening and then widening the distance from the second lens group G2.

  In order from the object side, the first lens group G1 includes a negative meniscus lens having a convex surface facing the object side and a positive meniscus lens having a convex surface facing the object side. The second lens group G2 has a convex surface facing the object side. The third lens group G3 is composed of a positive meniscus lens, a negative meniscus lens having a convex surface facing the object side, and a positive meniscus lens having a convex surface facing the object side. Consists of a single meniscus lens. The aperture stop S is positioned on the image side of the most object side surface of the three-piece cemented lens of the second lens group G2.

  The aspherical surfaces are the image side surface of the negative meniscus lens of the first lens group G1, the most object side surface and the most image side surface of the triplet cemented lens of the second lens group G2, and the positive meniscus of the third lens group G3. It is used for four surfaces on the object side of the lens.

  As shown in FIG. 17, the zoom optical system according to the seventeenth embodiment includes, in order from the object side, a first lens unit G1 having a negative refractive power, an aperture stop S, a second lens unit G2 having a positive refractive power, and a first lens unit having a positive refractive power. The first lens group G1 moves in a concave locus on the object side when zooming from the wide-angle end to the telephoto end, and at the telephoto end is closer to the image side than the wide-angle end. Located in. The aperture stop S and the second lens group G2 move monotonously toward the object side while integrally reducing the distance between the first lens group G1. The third lens group G3 moves toward the object side while widening the distance from the second lens group G2.

  In order from the object side, the first lens group G1 includes a negative meniscus lens having a convex surface facing the object side and a positive meniscus lens having a convex surface facing the object side. The second lens group G2 has a convex surface facing the object side. The third lens group G3 is composed of a positive meniscus lens, a negative meniscus lens having a convex surface facing the object side, and a positive meniscus lens having a convex surface facing the object side. Consists of a single meniscus lens. The aperture stop S is positioned on the image side of the most object side surface of the three-piece cemented lens of the second lens group G2.

  The aspherical surfaces are the image side surface of the negative meniscus lens of the first lens group G1, the most object side surface and the most image side surface of the triplet cemented lens of the second lens group G2, and the positive meniscus of the third lens group G3. It is used for four surfaces on the object side of the lens.

In the following, the numerical data of each of the above embodiments is shown. Symbols are the above, f is the total focal length, _FNO is the F number, WE is the wide angle end, ST is the intermediate state, TE is the telephoto end, r ₁ , R ₂ ... Are the radii of curvature of the lens surfaces, d ₁ , d ₂ ... _Are the distances between the lens surfaces, n _d1 , n _d2 are the refractive indices of the d-line of each lens, and ν _d1 , ν _d2 . It is the Abbe number of the lens. The aspherical shape is represented by the following formula, where x is an optical axis with the light traveling direction being positive, and y is a direction orthogonal to the optical axis.

x = (y ² / r) / [1+ {1- (K + 1) (y / r) ² } ^1/2 ]
+ A ₄ y ⁴ + A ₆ y ⁶ + A ₈ y ⁸ + A ₁₀ y ¹⁰ + A ₁₂ y ¹²
Where r is the paraxial radius of curvature, K is the conic coefficient, and A ₄ , A ₆ , A ₈ , A ₁₀ , and A ₁₂ are the fourth, sixth, eighth, tenth, and twelfth aspheric coefficients, respectively. .

Example 1
r ₁ = 51.789 d ₁ = 0.70 n _d1 = 1.88300 ν _d1 = 40.76
r ₂ = 5.837 d ₂ = 1.71
r ₃ = 13.554 (aspherical surface) d ₃ = 1.47 n _d2 = 1.82114 ν _d2 = 24.06
r ₄ = 75.183 (aspherical surface) d ₄ = (variable)
r ₅ = ∞ (aperture) d ₅ = -0.72
r ₆ = 3.826 (aspherical surface) d ₆ = 3.00 n _d3 = 1.49700 ν _d3 = 81.54
r ₇ = -19.669 d ₇ = 0.50 n _d4 = 1.92286 ν _d4 = 18.90
r ₈ = -133.221 d ₈ = 1.09 n _d5 = 1.69350 ν _d5 = 53.21
r ₉ = -23.946 (aspherical surface) d ₉ = (variable)
r ₁₀ = -68.471 (aspherical surface) d ₁₀ = 0.80 n _d6 = 1.52542 ν _d6 = 55.78
r ₁₁ = 7.284 (aspherical surface) d ₁₁ = (variable)
r ₁₂ = ∞ d ₁₂ = 0.50 n _d7 = 1.51633 ν _d7 = 64.14
r ₁₃ = ∞ d ₁₃ = 0.50
r ₁₄ = ∞ d ₁₄ = 0.50 n _d8 = 1.51633 ν _d8 = 64.14
r ₁₅ = ∞ d ₁₅ = 0.41
r ₁₆ = ∞ (image plane)
Aspheric coefficient 3rd surface K = 0.000
A ₄ = -2.90406 × 10 ^-4
A ₆ = -2.19067 × 10 ^-5
A ₈ = 1.93834 × 10 ^-6
A ₁₀ = -3.55926 × 10 ^-8
4th surface K = 0.000
A ₄ = -6.25636 × 10 ^-4
A ₆ = -1.55735 × 10 ^-5
A ₈ = 1.40541 × 10 ^-6
A ₁₀ = -3.74784 × 10 ^-8
6th surface K = 0.000
A ₄ = -3.84634 × 10 ^-4
A ₆ = -1.86499 × 10 ^-5
A ₈ = 9.97230 × 10 ^-6
A ₁₀ = -5.98509 × 10 ^-7
Surface 9 K = 0.000
A ₄ = 3.29823 × 10 ^-3
A ₆ = 2.17032 × 10 ^-4
A ₈ = -1.07505 × 10 ^-5
A ₁₀ = 8.77866 × 10 ^-6
10th surface K = 0.000
A ₄ = 9.19324 × 10 ^-4
A ₆ = -7.15668 × 10 ^-4
A ₈ = 2.38646 × 10 ^-4
A ₁₀ = -2.14848 × 10 ^-5
11th surface K = 0.000
A ₄ = 1.04459 × 10 ^-3
A ₆ = -5.99256 × 10 ^-4
A ₈ = 2.45269 × 10 ^-4
A ₁₀ = -2.50329 × 10 ^-5
Zoom data (∞)
WE ST TE
f (mm) 6.795 11.618 19.666
F _NO 3.43 4.34 5.81
d ₄ 14.53 6.17 1.12
d ₉ 1.97 2.41 3.21
d ₁₁ 5.80 8.08 11.34.

Example 2
r ₁ = -68.489 d ₁ = 1.00 n _d1 = 1.80610 ν _d1 = 40.92
r ₂ = 4.409 (aspherical surface) d ₂ = 1.19
r ₃ = 8.039 d ₃ = 1.67 n _d2 = 2.00069 ν _d2 = 25.46
r ₄ = 23.572 d ₄ = (variable)
r ₅ = ∞ (aperture) d ₅ = -0.50
r ₆ = 3.689 (aspherical surface) d ₆ = 3.79 n _d3 = 1.49700 ν _d3 = 81.54
r ₇ = -10.025 d ₇ = 1.00 n _d4 = 1.84666 ν _d4 = 23.78
r ₈ = -28.095 (aspherical surface) d ₈ = (variable)
r ₉ = -4.148 d ₉ = 0.80 n _d5 = 1.88300 ν _d5 = 40.76
r ₁₀ = -5.287 d ₁₀ = (variable)
r ₁₁ = ∞ d ₁₁ = 0.50 n _d6 = 1.51633 ν _d6 = 64.14
r ₁₂ = ∞ d ₁₂ = 0.50
r ₁₃ = ∞ d ₁₃ = 0.50 n _d7 = 1.51633 ν _d7 = 64.14
r ₁₄ = ∞ d ₁₄ = 0.59
r ₁₅ = ∞ (image plane)
Aspheric coefficient 2nd surface K = -0.549
A ₄ = -1.09327 × 10 ^-4
A ₆ = -1.43880 × 10 ^-5
A ₈ = 1.34815 × 10 ^-7
A ₁₀ = -5.73863 × 10 ^-9
6th surface K = -0.795
A ₄ = 1.48463 × 10 ^-3
A ₆ = 3.05264 × 10 ^-5
A ₈ = 1.15726 × 10 ^-5
A ₁₀ = -1.32653 × 10 ^-7
8th surface K = 0.000
A ₄ = 2.40186 × 10 ^-3
A ₆ = 2.76882 × 10 ^-4
A ₈ = -3.25134 × 10 ^-5
A ₁₀ = 9.56196 × 10 ^-6
Zoom data (∞)
WE ST TE
f (mm) 6.276 10.701 18.198
F _NO 3.25 4.16 5.74
d ₄ 11.19 4.99 1.50
d ₈ 3.56 4.37 4.93
d ₁₀ 4.21 6.63 11.70.

Example 3
r ₁ = 14898.846 d ₁ = 1.00 n _d1 = 1.88300 ν _d1 = 40.76
r ₂ = 6.423 (aspherical surface) d ₂ = 2.11
r ₃ = 10.315 d ₃ = 1.30 n _d2 = 1.92286 ν _d2 = 20.88
r ₄ = 20.902 d ₄ = (variable)
r ₅ = ∞ (aperture) d ₅ = 0.00
r ₆ = 4.307 (aspherical surface) d ₆ = 3.06 n _d3 = 1.49700 ν _d3 = 81.54
r ₇ = -7.020 d ₇ = 0.50 n _d4 = 1.67270 ν _d4 = 32.10
r ₈ = -100.000 d ₈ = 1.27 n _d5 = 1.58913 ν _d5 = 61.14
r ₉ = -15.900 (aspherical surface) d ₉ = (variable)
r ₁₀ = -20.236 (aspherical surface) d ₁₀ = 1.00 n _d6 = 1.69350 ν _d6 = 53.21
r ₁₁ = 20.000 (aspherical surface) d ₁₁ = (variable)
r ₁₂ = ∞ d ₁₂ = 0.91 n _d7 = 1.53996 ν _d7 = 59.45
r ₁₃ = ∞ d ₁₃ = 0.28
r ₁₄ = ∞ d ₁₄ = 0.53 n _d8 = 1.51633 ν _d8 = 64.14
r ₁₅ = ∞ d ₁₅ = 0.59
r ₁₆ = ∞ (image plane)
Aspheric coefficient 2nd surface K = 0.000
A ₄ = -2.21409 × 10 ^-4
A ₆ = 1.77359 × 10 ^-6
A ₈ = -8.59542 × 10 ^-7
A ₁₀ = 2.17513 × 10 ^-8
6th surface K = 0.000
A ₄ = -5.81631 × 10 ^-4
A ₆ = 7.05939 × 10 ^-6
A ₈ = 7.18180 × 10 ^-7
A ₁₀ = 7.05689 × 10 ^-8
Surface 9 K = 0.000
A ₄ = 1.51118 × 10 ^-3
A ₆ = 1.78503 × 10 ^-4
A ₈ = -1.96850 × 10 ^-5
A ₁₀ = 2.82432 × 10 ^-6
10th face K = -309.655
A ₄ = -1.11996 × 10 ^-2
A ₆ = 1.06613 × 10 ^-3
A ₈ = -1.64863 × 10 ^-4
A ₁₀ = 1.16951 × 10 ^-5
11th surface K = 0.000
A ₄ = -5.95012 × 10 ^-3
A ₆ = 2.46173 × 10 ^-4
A ₈ = -1.14677 × 10 ^-5
A ₁₀ = 1.07814 × 10 ^-6
Zoom data (∞)
WE ST TE
f (mm) 6.810 11.619 19.820
F _NO 2.85 3.78 5.37
d ₄ 10.21 4.20 0.66
d ₉ 5.91 5.95 6.02
d ₁₁ 1.41 4.34 9.31.

Example 4
r ₁ = -31.828 d ₁ = 0.70 n _d1 = 1.88300 ν _d1 = 40.76
r ₂ = 7.165 d ₂ = 0.78
r ₃ = 9.148 (aspherical surface) d ₃ = 1.52 n _d2 = 1.84666 ν _d2 = 23.78
r ₄ = 33.352 d ₄ = (variable)
r ₅ = ∞ (aperture) d ₅ = -0.18
r ₆ = 4.692 (aspherical surface) d ₆ = 1.67 n _d3 = 1.67790 ν _d3 = 55.34
r ₇ = -12.027 d ₇ = 0.50 n _d4 = 2.00069 ν _d4 = 25.46
r ₈ = 77.997 d ₈ = 2.59 n _d5 = 1.58313 ν _d5 = 59.38
r ₉ = -55.116 (aspherical surface) d ₉ = (variable)
r ₁₀ = -30.436 (aspherical surface) d ₁₀ = 0.80 n _d6 = 1.50913 ν _d6 = 56.20
r ₁₁ = 23.726 (aspherical surface) d ₁₁ = (variable)
r ₁₂ = ∞ d ₁₂ = 0.84 n _d7 = 1.53996 ν _d7 = 59.45
r ₁₃ = ∞ d ₁₃ = 0.26
r ₁₄ = ∞ d ₁₄ = 0.49 n _d8 = 1.51633 ν _d8 = 64.14
r ₁₅ = ∞ d ₁₅ = 0.59
r ₁₆ = ∞ (image plane)
Aspheric coefficient 3rd surface K = 0.000
A ₄ = 1.15680 × 10 ^-4
A ₆ = -1.45503 × 10 ^-5
A ₈ = 1.52852 × 10 ^-6
A ₁₀ = -4.11662 × 10 ^-8
6th surface K = 0.000
A ₄ = -1.51567 × 10 ^-4
A ₆ = 5.06933 × 10 ^-5
A ₈ = -3.20524 × 10 ^-6
A ₁₀ = 3.54327 × 10 ^-7
Surface 9 K = 0.000
A ₄ = 2.49728 × 10 ^-3
A ₆ = 2.38997 × 10 ^-4
A ₈ = -1.91765 × 10 ^-5
A ₁₀ = 5.71179 × 10 ^-6
10th surface K = 0.000
A ₄ = -5.74352 × 10 ^-3
A ₆ = -5.59898 × 10 ^-4
A ₈ = 1.35762 × 10 ^-4
A ₁₀ = -3.60148 × 10 ^-6
11th surface K = 0.000
A ₄ = -5.41979 × 10 ^-3
A ₆ = -2.65317 × 10 ^-4
A ₈ = 7.68566 × 10 ^-5
A ₁₀ = -1.65036 × 10 ^-6
Zoom data (∞)
WE ST TE
f (mm) 6.809 11.596 19.747
F _NO 3.34 4.26 5.90
d ₄ 10.75 4.21 0.58
d ₉ 5.22 5.97 6.26
d ₁₁ 1.86 3.91 8.41.

Example 5
r ₁ = -123.809 d ₁ = 0.70 n _d1 = 1.88300 ν _d1 = 40.76
r ₂ = 6.941 d ₂ = 0.99
r ₃ = 9.801 (aspherical surface) d ₃ = 1.63 n _d2 = 1.84666 ν _d2 = 23.78
r ₄ = 29.771 (aspherical surface) d ₄ = (variable)
r ₅ = ∞ (aperture) d ₅ = -0.52
r ₆ = 3.591 (aspherical surface) d ₆ = 1.97 n _d3 = 1.49700 ν _d3 = 81.54
r ₇ = -23.495 d ₇ = 0.50 n _d4 = 1.92286 ν _d4 = 18.90
r ₈ = -93.239 d ₈ = 1.79 n _d5 = 1.51633 ν _d5 = 64.14
r ₉ = -160.642 (aspherical surface) d ₉ = (variable)
r ₁₀ = -16.790 (aspherical surface) d ₁₀ = 0.80 n _d6 = 1.50913 ν _d6 = 56.20
r ₁₁ = 22.686 (aspherical surface) d ₁₁ = (variable)
r ₁₂ = ∞ d ₁₂ = 0.50 n _d7 = 1.51633 ν _d7 = 64.14
r ₁₃ = ∞ d ₁₃ = 0.50
r ₁₄ = ∞ d ₁₄ = 0.50 n _d8 = 1.51633 ν _d8 = 64.14
r ₁₅ = ∞ d ₁₅ = 0.40
r ₁₆ = ∞ (image plane)
Aspheric coefficient 3rd surface K = 0.000
A ₄ = -2.75036 × 10 ^-4
A ₆ = -3.07840 × 10 ^-5
A ₈ = 1.58082 × 10 ^-6
A ₁₀ = -3.29070 × 10 ^-8
4th surface K = 0.000
A ₄ = -3.71542 × 10 ^-4
A ₆ = -3.43210 × 10 ^-5
A ₈ = 2.04735 × 10 ^-6
A ₁₀ = -5.01217 × 10 ^-8
6th surface K = 0.000
A ₄ = -4.17928 × 10 ^-4
A ₆ = 2.46517 × 10 ^-5
A ₈ = 2.80412 × 10 ^-6
A ₁₀ = -3.23125 × 10 ^-7
Surface 9 K = 0.000
A ₄ = 4.85479 × 10 ^-3
A ₆ = 4.60043 × 10 ^-4
A ₈ = -8.22251 × 10 ^-6
A ₁₀ = 1.98515 × 10 ^-5
10th surface K = 0.000
A ₄ = -2.47640 × 10 ^-3
A ₆ = -2.34974 × 10 ^-4
A ₈ = 1.88850 × 10 ^-4
A ₁₀ = -1.61128 × 10 ^-5
11th surface K = 0.000
A ₄ = -1.93357 × 10 ^-3
A ₆ = -1.52885 × 10 ^-4
A ₈ = 1.29934 × 10 ^-4
A ₁₀ = -1.10625 × 10 ^-5
Zoom data (∞)
WE ST TE
f (mm) 6.812 11.596 19.749
F _NO 3.33 4.32 5.80
d ₄ 12.84 5.76 0.92
d ₉ 3.15 2.84 3.65
d ₁₁ 3.85 7.17 10.57.

Example 6
r ₁ = -21692.039 d ₁ = 1.00 n _d1 = 1.80610 ν _d1 = 40.92
r ₂ = 8.032 (aspherical surface) d ₂ = 1.37
r ₃ = 9.774 d ₃ = 2.22 n _d2 = 2.00069 ν _d2 = 25.46
r ₄ = 16.834 d ₄ = (variable)
r ₅ = ∞ (aperture) d ₅ = -0.82
r ₆ = 4.180 (aspherical surface) d ₆ = 2.46 n _d3 = 1.49700 ν _d3 = 81.54
r ₇ = -32.928 d ₇ = 1.47 n _d4 = 1.92286 ν _d4 = 18.90
r ₈ = -955.516 d ₈ = 1.93 n _d5 = 1.49700 ν _d5 = 81.54
r ₉ = 163.416 (aspherical surface) d ₉ = (variable)
r ₁₀ = -42.579 (aspherical surface) d ₁₀ = 0.80 n _d6 = 1.52511 ν _d6 = 56.22
r ₁₁ = 13.093 (aspherical surface) d ₁₁ = (variable)
r ₁₂ = ∞ d ₁₂ = 0.50 n _d7 = 1.51633 ν _d7 = 64.14
r ₁₃ = ∞ d ₁₃ = 0.50
r ₁₄ = ∞ d ₁₄ = 0.50 n _d8 = 1.51633 ν _d8 = 64.14
r ₁₅ = ∞ d ₁₅ = 0.41
r ₁₆ = ∞ (image plane)
Aspheric coefficient 2nd surface K = 0.000
A ₄ = -9.38394 × 10 ^-6
A ₆ = 5.54741 × 10 ^-8
A ₈ = -3.54097 × 10 ^-9
A ₁₀ = -4.67171 × 10 ^-10
6th surface K = 0.000
A ₄ = -4.42518 × 10 ^-4
A ₆ = -2.07748 × 10 ^-5
A ₈ = 2.18064 × 10 ^-6
A ₁₀ = -2.04579 × 10 ^-7
Surface 9 K = 0.000
A ₄ = 2.86385 × 10 ^-3
A ₆ = 3.70120 × 10 ^-4
A ₈ = -4.41500 × 10 ^-5
A ₁₀ = 8.47589 × 10 ^-6
10th surface K = 0.000
A ₄ = -5.63885 × 10 ^-3
A ₆ = 5.08036 × 10 ^-4
A ₈ = -4.05295 × 10 ^-5
A ₁₀ = 3.08061 × 10 ^-6
11th surface K = 0.000
A ₄ = -5.20991 × 10 ^-3
A ₆ = 3.91246 × 10 ^-4
A ₈ = -1.66900 × 10 ^-5
A ₁₀ = 6.24580 × 10 ^-7
Zoom data (∞)
WE ST TE
f (mm) 8.160 13.643 23.512
F _NO 2.88 3.56 4.96
d ₄ 17.18 6.85 1.22
d ₉ 3.96 4.61 4.33
d ₁₁ 3.52 5.32 10.55.

Example 7
r ₁ = -34.705 d ₁ = 0.95 n _d1 = 1.80610 ν _d1 = 40.92
r ₂ = 7.051 (aspherical surface) d ₂ = 1.54
r ₃ = 12.304 d ₃ = 2.07 n _d2 = 2.00069 ν _d2 = 25.46
r ₄ = 52.168 d ₄ = (variable)
r ₅ = ∞ (aperture) d ₅ = -1.18
r ₆ = 4.577 (aspherical surface) d ₆ = 2.64 n _d3 = 1.49700 ν _d3 = 81.54
r ₇ = 87.702 d ₇ = 0.60 n _d4 = 1.80810 ν _d4 = 22.76
r ₈ = 14.053 d ₈ = 2.21 n _d5 = 1.49700 ν _d5 = 81.54
r ₉ = -65.670 (aspherical surface) d ₉ = (variable)
r ₁₀ = -22.159 (aspherical surface) d ₁₀ = 0.80 n _d6 = 1.52542 ν _d6 = 55.78
r ₁₁ = 130.774 (aspherical surface) d ₁₁ = (variable)
r ₁₂ = ∞ d ₁₂ = 0.50 n _d7 = 1.53996 ν _d7 = 59.45
r ₁₃ = ∞ d ₁₃ = 0.50
r ₁₄ = ∞ d ₁₄ = 0.50 n _d8 = 1.51633 ν _d8 = 64.14
r ₁₅ = ∞ d ₁₅ = 0.42
r ₁₆ = ∞ (image plane)
Aspheric coefficient 2nd surface K = 0.000
A ₄ = -2.39358 × 10 ^-4
A ₆ = -5.68999 × 10 ^-6
A ₈ = 1.10603 × 10 ^-7
A ₁₀ = -4.44730 × 10 ^-9
6th surface K = 0.000
A ₄ = -2.30366 × 10 ^-4
A ₆ = 8.36646 × 10 ^-7
A ₈ = 9.08393 × 10 ^-8
A ₁₀ = 0
Surface 9 K = 0.000
A ₄ = 2.56285 × 10 ^-3
A ₆ = 2.19102 × 10 ^-5
A ₈ = 4.74149 × 10 ^-5
A ₁₀ = -7.24474 × 10 ^-6
A ₁₂ = 6.43200 × 10 ^-7
10th surface K = 0.000
A ₄ = 1.96811 × 10 ^-4
A ₆ = -1.09241 × 10 ^-4
A ₈ = 9.88849 × 10 ^-6
A ₁₀ = -2.12643 × 10 ^-7
11th surface K = 0.000
A ₄ = 1.82798 × 10 ^-4
A ₆ = -4.12618 × 10 ^-5
A ₈ = -2.94854 × 10 ^-7
A ₁₀ = 0
Zoom data (∞)
WE ST TE
f (mm) 8.157 13.668 23.513
F _NO 2.88 3.70 5.04
d ₄ 15.90 7.41 1.58
d ₉ 3.13 2.89 4.38
d ₁₁ 7.19 11.42 15.92.

Example 8
r ₁ = 50.852 d ₁ = 0.90 n _d1 = 1.80610 ν _d1 = 40.92
r ₂ = 5.799 (aspherical surface) d ₂ = 1.89
r ₃ = 9.201 d ₃ = 1.76 n _d2 = 2.00069 ν _d2 = 25.46
r ₄ = 16.258 d ₄ = (variable)
r ₅ = ∞ (aperture) d ₅ = -0.60
r ₆ = 5.636 (aspherical surface) d ₆ = 2.63 n _d3 = 1.74320 ν _d3 = 49.34
r ₇ = 11.974 d ₇ = 1.71 n _d4 = 1.80518 ν _d4 = 25.42
r ₈ = 4.090 d ₈ = 1.25 n _d5 = 1.58313 ν _d5 = 59.38
r ₉ = 13.539 (aspherical surface) d ₉ = (variable)
r ₁₀ = 18.182 (aspherical surface) d ₁₀ = 1.50 n _d6 = 1.52542 ν _d6 = 55.78
r ₁₁ = -61.937 d ₁₁ = (variable)
r ₁₂ = ∞ d ₁₂ = 0.50 n _d7 = 1.51633 ν _d7 = 64.14
r ₁₃ = ∞ d ₁₃ = 0.50
r ₁₄ = ∞ d ₁₄ = 0.50 n _d8 = 1.51633 ν _d8 = 64.14
r ₁₅ = ∞ d ₁₅ = 0.49
r ₁₆ = ∞ (image plane)
Aspheric coefficient 2nd surface K = -1.118
A ₄ = 4.40772 × 10 ^-4
A ₆ = -1.79165 × 10 ^-7
A ₈ = 6.84992 × 10 ^-8
A ₁₀ = -4.27115 × 10 ^-10
6th surface K = -0.831
A ₄ = 5.53954 × 10 ^-4
A ₆ = -6.08508 × 10 ^-7
A ₈ = 1.25836 × 10 ^-6
A ₁₀ = -3.07335 × 10 ^-8
Surface 9 K = 0.000
A ₄ = 1.86701 × 10 ^-3
A ₆ = 9.48986 × 10 ^-5
A ₈ = -1.36654 × 10 ^-7
A ₁₀ = 1.56679 × 10 ^-6
10th surface K = 0.000
A ₄ = -7.43754 × 10 ^-5
A ₆ = 7.82756 × 10 ^-6
A ₈ = 0
A ₁₀ = 0
Zoom data (∞)
WE ST TE
f (mm) 7.904 15.227 22.840
F _NO 2.97 3.93 4.95
d ₄ 16.00 4.96 1.00
d ₉ 3.47 3.89 5.15
d ₁₁ 7.19 12.46 17.93.

Example 9
r ₁ = -55.947 d ₁ = 0.90 n _d1 = 1.80610 ν _d1 = 40.92
r ₂ = 6.646 (aspherical surface) d ₂ = 1.62
r ₃ = 11.161 d ₃ = 1.82 n _d2 = 2.00069 ν _d2 = 25.46
r ₄ = 30.512 d ₄ = (variable)
r ₅ = ∞ (aperture) d ₅ = -0.67
r ₆ = 5.808 (aspherical surface) d ₆ = 3.51 n _d3 = 1.74320 ν _d3 = 49.34
r ₇ = 16.319 d ₇ = 0.60 n _d4 = 1.84666 ν _d4 = 23.78
r ₈ = 5.200 d ₈ = 1.36 n _d5 = 1.58313 ν _d5 = 59.38
r ₉ = 26.430 (aspherical surface) d ₉ = (variable)
r ₁₀ = 24.745 (aspherical surface) d ₁₀ = 1.24 n _d6 = 1.52542 ν _d6 = 55.78
r ₁₁ = 7929.558 d ₁₁ = (variable)
r ₁₂ = ∞ d ₁₂ = 0.50 n _d7 = 1.51633 ν _d7 = 64.14
r ₁₃ = ∞ d ₁₃ = 0.50
r ₁₄ = ∞ d ₁₄ = 0.50 n _d8 = 1.51633 ν _d8 = 64.14
r ₁₅ = ∞ d ₁₅ = 0.46
r ₁₆ = ∞ (image plane)
Aspheric coefficient 2nd surface K = -3.702
A ₄ = 1.29210 × 10 ^-3
A ₆ = -2.94031 × 10 ^-5
A ₈ = 6.63852 × 10 ^-7
A ₁₀ = -7.48401 × 10 ^-9
6th surface K = -2.011
A ₄ = 1.29270 × 10 ^-3
A ₆ = -8.81428 × 10 ^-6
A ₈ = 1.57107 × 10 ^-6
A ₁₀ = -3.88466 × 10 ^-8
Surface 9 K = 0.000
A ₄ = 1.94125 × 10 ^-3
A ₆ = 3.03189 × 10 ^-5
A ₈ = 1.16357 × 10 ^-5
A ₁₀ = 1.55401 × 10 ^-7
10th surface K = 0.000
A ₄ = -1.01517 × 10 ^-4
A ₆ = 5.70765 × 10 ^-6
A ₈ = 0
A ₁₀ = 0
Zoom data (∞)
WE ST TE
f (mm) 7.511 14.600 21.633
F _NO 2.88 3.86 4.84
d ₄ 15.42 4.74 1.07
d ₉ 4.10 4.19 4.41
d ₁₁ 6.28 11.59 16.78.

Example 10
r ₁ = -200.434 d ₁ = 0.90 n _d1 = 1.80610 ν _d1 = 40.92
r ₂ = 6.474 (aspherical surface) d ₂ = 1.53
r ₃ = 9.933 d ₃ = 2.02 n _d2 = 2.00069 ν _d2 = 25.46
r ₄ = 21.902 d ₄ = (variable)
r ₅ = ∞ (aperture) d ₅ = -0.63
r ₆ = 5.753 (aspherical surface) d ₆ = 2.06 n _d3 = 1.80610 ν _d3 = 40.92
r ₇ = 35.230 d ₇ = 1.27 n _d4 = 1.84666 ν _d4 = 23.78
r ₈ = 5.202 d ₈ = 2.06 n _d5 = 1.58313 ν _d5 = 59.38
r ₉ = 16.552 (aspherical surface) d ₉ = (variable)
r ₁₀ = 14.000 (aspherical surface) d ₁₀ = 1.24 n _d6 = 1.52542 ν _d6 = 55.78
r ₁₁ = 41.056 d ₁₁ = (variable)
r ₁₂ = ∞ d ₁₂ = 0.50 n _d7 = 1.51633 ν _d7 = 64.14
r ₁₃ = ∞ d ₁₃ = 0.50
r ₁₄ = ∞ d ₁₄ = 0.50 n _d8 = 1.51633 ν _d8 = 64.14
r ₁₅ = ∞ d ₁₅ = 0.43
r ₁₆ = ∞ (image plane)
Aspheric coefficient 2nd surface K = -3.501
A ₄ = 1.39590 × 10 ^-3
A ₆ = -2.94154 × 10 ^-5
A ₈ = 6.73010 × 10 ^-7
A ₁₀ = -7.13429 × 10 ^-9
6th page K = -2.429
A ₄ = 1.61259 × 10 ^-3
A ₆ = -1.94631 × 10 ^-5
A ₈ = 2.01443 × 10 ^-6
A ₁₀ = -5.44542 × 10 ^-8
Surface 9 K = -4.333
A ₄ = 2.27790 × 10 ^-3
A ₆ = 1.03782 × 10 ^-5
A ₈ = 2.09837 × 10 ^-5
A ₁₀ = -4.69417 × 10 ^-7
10th surface K = 0.000
A ₄ = -1.47199 × 10 ^-4
A ₆ = 5.67379 × 10 ^-6
A ₈ = 4.82046 × 10 ^-7
A ₁₀ = -1.84788 × 10 ^-8
Zoom data (∞)
WE ST TE
f (mm) 7.512 14.376 21.635
F _NO 2.88 3.78 4.76
d ₄ 16.35 5.11 1.03
d ₉ 4.20 4.23 4.65
d ₁₁ 5.83 10.66 15.58.

Example 11
r ₁ = 31.493 d ₁ = 1.00 n _d1 = 1.80610 ν _d1 = 40.92
r ₂ = 4.015 (aspherical surface) d ₂ = 1.36
r ₃ = 6.467 (aspherical surface) d ₃ = 1.80 n _d2 = 1.84666 ν _d2 = 23.78
r ₄ = 13.950 d ₄ = (variable)
r ₅ = ∞ (aperture) d ₅ = -0.45
r ₆ = 3.743 (aspherical surface) d ₆ = 1.30 n _d3 = 1.74320 ν _d3 = 49.34
r ₇ = 20.976 d ₇ = 0.50 n _d4 = 1.71736 ν _d4 = 29.52
r ₈ = 3.002 d ₈ = 2.03 n _d5 = 1.51633 ν _d5 = 64.14
r ₉ = 9.297 (aspherical surface) d ₉ = (variable)
r ₁₀ = 19.045 (aspherical surface) d ₁₀ = 1.00 n _d6 = 1.52511 ν _d6 = 56.23
r ₁₁ = -241.584 (aspherical surface) d ₁₁ = (variable)
r ₁₂ = ∞ d ₁₂ = 0.50 n _d7 = 1.51633 ν _d7 = 64.14
r ₁₃ = ∞ d ₁₃ = 0.50
r ₁₄ = ∞ d ₁₄ = 0.50 n _d8 = 1.51633 ν _d8 = 64.14
r ₁₅ = ∞ d ₁₅ = 0.42
r ₁₆ = ∞ (image plane)
Aspheric coefficient 2nd surface K = -0.788
A ₄ = 5.88309 × 10 ^-4
A ₆ = 1.25094 × 10 ^-5
A ₈ = -6.84764 × 10 ^-8
A ₁₀ = 1.92475 × 10 ^-9
Third side K = 0.000
A ₄ = 2.80805 × 10 ^-10
A ₆ = 7.99547 × 10 ^-7
A ₈ = -3.58622 × 10 ^-12
A ₁₀ = 0
6th surface K = -1.016
A ₄ = 2.19556 × 10 ^-3
A ₆ = 9.52058 × 10 ^-5
A ₈ = 2.20537 × 10 ^-6
A ₁₀ = -7.19757 × 10 ^-8
Surface 9 K = 0.000
A ₄ = 6.49949 × 10 ^-3
A ₆ = 6.51196 × 10 ^-4
A ₈ = 8.19880 × 10 ^-5
A ₁₀ = 1.62716 × 10 ^-5
10th surface K = 0.000
A ₄ = -8.16440 × 10 ^-11
A ₆ = 4.00208 × 10 ^-5
A ₈ = 1.51332 × 10 ^-5
A ₁₀ = 2.94028 × 10 ^-6
11th surface K = 0.000
A ₄ = 7.72945 × 10 ^-7
A ₆ = 5.03191 × 10 ^-5
A ₈ = -1.14557 × 10 ^-5
A ₁₀ = 4.64487 × 10 ^-6
Zoom data (∞)
WE ST TE
f (mm) 5.530 10.000 16.036
F _NO 3.48 4.49 5.80
d ₄ 12.20 4.63 0.95
d ₉ 2.50 3.01 2.50
d ₁₁ 4.47 7.38 12.10.

Example 12
r ₁ = -64.454 d ₁ = 1.00 n _d1 = 1.80610 ν _d1 = 40.92
r ₂ = 8.621 (aspherical surface) d ₂ = 1.73
r ₃ = 11.128 d ₃ = 2.00 n _d2 = 1.92286 ν _d2 = 20.88
r ₄ = 19.611 d ₄ = (variable)
r ₅ = ∞ (aperture) d ₅ = -0.60
r ₆ = 6.134 (aspherical surface) d ₆ = 2.80 n _d3 = 1.80610 ν _d3 = 40.92
r ₇ = -9.307 d ₇ = 0.50 n _d4 = 1.67270 ν _d4 = 32.10
r ₈ = 3.844 d ₈ = 2.63 n _d5 = 1.48749 ν _d5 = 70.23
r ₉ = 10.458 (aspherical surface) d ₉ = (variable)
r ₁₀ = 11.453 d ₁₀ = 1.80 n _d6 = 1.52542 ν _d6 = 55.78
r ₁₁ = 28.905 d ₁₁ = (variable)
r ₁₂ = ∞ d ₁₂ = 0.60 n _d7 = 1.51633 ν _d7 = 64.14
r ₁₃ = ∞ d ₁₃ = 0.60
r ₁₄ = ∞ d ₁₄ = 0.60 n _d8 = 1.51633 ν _d8 = 64.14
r ₁₅ = ∞ d ₁₅ = 0.56
r ₁₆ = ∞ (image plane)
Aspheric coefficient 2nd surface K = -0.790
A ₄ = 1.13709 × 10 ^-4
A ₆ = 1.36096 × 10 ^-6
A ₈ = -5.03816 × 10 ^-8
A ₁₀ = 1.20255 × 10 ^-9
6th surface K = -0.006
A ₄ = -1.89441 × 10 ^-4
A ₆ = -6.95916 × 10 ^-6
A ₈ = 1.29909 × 10 ^-7
A ₁₀ = -1.96262 × 10 ^-8
The ninth side K = -2.043
A ₄ = 1.74384 × 10 ^-3
A ₆ = 3.87068 × 10 ^-5
A ₈ = 2.76989 × 10 ^-6
A ₁₀ = -2.97263 × 10 ^-8
Zoom data (∞)
WE ST TE
f (mm) 8.257 11.083 23.726
F _NO 2.85 3.22 4.89
d ₄ 14.53 9.25 1.00
d ₉ 3.91 4.26 6.65
d ₁₁ 5.62 7.45 15.70.

Example 13
r ₁ = -120.395 d ₁ = 1.00 n _d1 = 1.80610 ν _d1 = 40.92
r ₂ = 7.653 (aspherical surface) d ₂ = 1.60
r ₃ = 10.272 d ₃ = 1.60 n _d2 = 1.92286 ν _d2 = 20.88
r ₄ = 19.021 d ₄ = (variable)
r ₅ = ∞ (aperture) d ₅ = -0.60
r ₆ = 6.092 (aspherical surface) d ₆ = 2.70 n _d3 = 1.80610 ν _d3 = 40.92
r ₇ = -8.957 d ₇ = 0.50 n _d4 = 1.67270 ν _d4 = 32.10
r ₈ = 3.826 d ₈ = 2.00 n _d5 = 1.49700 ν _d5 = 81.54
r ₉ = 9.512 (aspherical surface) d ₉ = (variable)
r ₁₀ = 14.529 d ₁₀ = 1.60 n _d6 = 1.51633 ν _d6 = 64.14
r ₁₁ = 507.947 d ₁₁ = (variable)
r ₁₂ = ∞ d ₁₂ = 0.60 n _d7 = 1.51633 ν _d7 = 64.14
r ₁₃ = ∞ d ₁₃ = 0.60
r ₁₄ = ∞ d ₁₄ = 0.60 n _d8 = 1.51633 ν _d8 = 64.14
r ₁₅ = ∞ d ₁₅ = 0.53
r ₁₆ = ∞ (image plane)
Aspheric coefficient 2nd surface K = -0.481
A ₄ = 5.33432 × 10 ^-5
A ₆ = 1.31789 × 10 ^-6
A ₈ = -1.87256 × 10 ^-8
A ₁₀ = -4.79094 × 10 ^-11
6th surface K = -0.117
A ₄ = -9.87240 × 10 ^-5
A ₆ = -5.15054 × 10 ^-6
A ₈ = 1.80533 × 10 ^-7
A ₁₀ = -2.13356 × 10 ^-8
Surface 9 K = -0.377
A ₄ = 1.63400 × 10 ^-3
A ₆ = 3.97670 × 10 ^-5
A ₈ = 2.09267 × 10 ^-6
A ₁₀ = 1.70358 × 10 ^-7
Zoom data (∞)
WE ST TE
f (mm) 7.793 13.201 22.406
F _NO 2.85 3.55 4.74
d ₄ 15.60 6.42 1.00
d ₉ 3.96 4.68 7.13
d ₁₁ 6.15 9.71 15.76.

Example 14
r ₁ = 69.726 d ₁ = 0.50 n _d1 = 1.69350 ν _d1 = 53.21
r ₂ = 4.746 d ₂ = 1.96
r ₃ = 12.885 (aspherical surface) d ₃ = 1.36 n _d2 = 1.84666 ν _d2 = 23.78
r ₄ = 25.844 (aspherical surface) d ₄ = (variable)
r ₅ = ∞ (aperture) d ₅ = -0.50
r ₆ = 4.943 (aspherical surface) d ₆ = 3.04 n _d3 = 1.74320 ν _d3 = 49.34
r ₇ = 25.950 d ₇ = 0.50 n _d4 = 1.71736 ν _d4 = 29.52
r ₈ = 3.545 d ₈ = 1.57 n _d5 = 1.51633 ν _d5 = 64.14
r ₉ = -140.225 (aspherical surface) d ₉ = (variable)
r ₁₀ = 36.103 d ₁₀ = 1.08 n _d6 = 1.58393 ν _d6 = 30.21
r ₁₁ = 157.196 d ₁₁ = (variable)
r ₁₂ = ∞ d ₁₂ = 0.50 n _d7 = 1.51633 ν _d7 = 64.14
r ₁₃ = ∞ d ₁₃ = 0.50
r ₁₄ = ∞ d ₁₄ = 0.50 n _d8 = 1.51633 ν _d8 = 64.14
r ₁₅ = ∞ d ₁₅ = 0.60
r ₁₆ = ∞ (image plane)
Aspheric coefficient 3rd surface K = 2.135
A ₄ = -3.15464 × 10 ^-4
A ₆ = -1.04123 × 10 ^-5
A ₈ = -2.90693 × 10 ^-7
A ₁₀ = 0
4th surface K = -1.605
A ₄ = -6.13441 × 10 ^-4
A ₆ = -1.89803 × 10 ^-5
A ₈ = -5.74661 × 10 ^-7
A ₁₀ = 0
6th surface K = -1.070
A ₄ = 9.28135 × 10 ^-4
A ₆ = 1.60749 × 10 ^-5
A ₈ = 9.55801 × 10 ^-7
A ₁₀ = 0
Surface 9 K = 0.000
A ₄ = 2.77025 × 10 ^-3
A ₆ = 8.45677 × 10 ^-5
A ₈ = 2.81700 × 10 ^-5
A ₁₀ = 0
Zoom data (∞)
WE ST TE
f (mm) 6.108 11.768 17.644
F _NO 3.24 4.42 5.65
d ₄ 10.68 3.49 0.90
d ₉ 3.68 3.69 3.68
d ₁₁ 4.04 8.76 13.77.

Example 15
r ₁ = 19.064 d ₁ = 0.80 n _d1 = 1.77250 ν _d1 = 49.60
r ₂ = 5.104 d ₂ = 1.87
r ₃ = 10.613 (aspherical surface) d ₃ = 1.50 n _d2 = 1.82114 ν _d2 = 24.06
r ₄ = 17.740 (aspherical surface) d ₄ = (variable)
r ₅ = ∞ (aperture) d ₅ = -0.50
r ₆ = 4.218 (aspherical surface) d ₆ = 1.25 n _d3 = 1.80610 ν _d3 = 40.92
r ₇ = 16.475 d ₇ = 0.50 n _d4 = 1.72825 ν _d4 = 28.46
r ₈ = 3.000 d ₈ = 1.98 n _d5 = 1.58313 ν _d5 = 59.38
r ₉ = 6.705 (aspherical surface) d ₉ = (variable)
r ₁₀ = 15.406 (aspherical surface) d ₁₀ = 1.20 n _d6 = 1.52511 ν _d6 = 56.22
r ₁₁ = 679.942 (aspherical surface) d ₁₁ = (variable)
r ₁₂ = ∞ d ₁₂ = 0.50 n _d7 = 1.51633 ν _d7 = 64.14
r ₁₃ = ∞ d ₁₃ = 0.50
r ₁₄ = ∞ d ₁₄ = 0.50 n _d8 = 1.51633 ν _d8 = 64.14
r ₁₅ = ∞ d ₁₅ = 0.40
r ₁₆ = ∞ (image plane)
Aspheric coefficient 3rd surface K = -13.399
A ₄ = 1.00692 × 10 ^-3
A ₆ = -5.17345 × 10 ^-5
A ₈ = 2.70682 × 10 ^-6
A ₁₀ = -8.69858 × 10 ^-8
4th surface K = 4.762
A ₄ = -9.39622 × 10 ^-4
A ₆ = 1.08563 × 10 ^-5
A ₈ = -5.52833 × 10 ^-7
A ₁₀ = -3.72262 × 10 ^-8
6th surface K = -1.661
A ₄ = 2.81854 × 10 ^-3
A ₆ = 3.99977 × 10 ^-5
A ₈ = 1.43030 × 10 ^-6
A ₁₀ = 1.39779 × 10 ^-7
Surface 9 K = -1.556
A ₄ = 5.79158 × 10 ^-3
A ₆ = 5.27276 × 10 ^-4
A ₈ = 2.64149 × 10 ^-7
A ₁₀ = 1.62265 × 10 ^-5
Surface 10 K = -14.699
A ₄ = 1.27364 × 10 ^-3
A ₆ = 1.39733 × 10 ^-4
A ₈ = 2.54309 × 10 ^-5
A ₁₀ = -7.92228 × 10 ^-7
11th surface K = 0.000
A ₄ = 6.13478 × 10 ^-4
A ₆ = 1.52095 × 10 ^-4
A ₈ = 7.94767 × 10 ^-6
A ₁₀ = 1.36613 × 10 ^-6
Zoom data (∞)
WE ST TE
f (mm) 6.610 12.752 19.108
F _NO 3.48 4.64 5.80
d ₄ 13.97 4.45 0.90
d ₉ 2.98 3.71 3.63
d ₁₁ 5.54 9.39 13.94.

Example 16
r ₁ = 23.044 d ₁ = 1.00 n _d1 = 1.80610 ν _d1 = 40.92
r ₂ = 4.637 (aspherical surface) d ₂ = 1.67
r ₃ = 6.786 d ₃ = 1.58 n _d2 = 2.00069 ν _d2 = 25.46
r ₄ = 10.000 d ₄ = (variable)
r ₅ = ∞ (aperture) d ₅ = -0.50
r ₆ = 4.414 (aspherical surface) d ₆ = 2.63 n _d3 = 1.74320 ν _d3 = 49.34
r ₇ = 10.000 d ₇ = 0.50 n _d4 = 1.80518 ν _d4 = 25.42
r ₈ = 3.572 d ₈ = 1.06 n _d5 = 1.58313 ν _d5 = 59.38
r ₉ = 9.779 (aspherical surface) d ₉ = (variable)
r ₁₀ = 12.767 (aspherical surface) d ₁₀ = 1.20 n _d6 = 1.52511 ν _d6 = 56.22
r ₁₁ = 450.005 d ₁₁ = (variable)
r ₁₂ = ∞ d ₁₂ = 0.50 n _d7 = 1.51633 ν _d7 = 64.14
r ₁₃ = ∞ d ₁₃ = 0.50
r ₁₄ = ∞ d ₁₄ = 0.50 n _d8 = 1.51633 ν _d8 = 64.14
r ₁₅ = ∞ d ₁₅ = 0.40
r ₁₆ = ∞ (image plane)
Aspheric coefficient 2nd surface K = -1.086
A ₄ = 9.62928 × 10 ^-4
A ₆ = 5.95705 × 10 ^-6
A ₈ = 3.29554 × 10 ^-7
A ₁₀ = 1.16736 × 10 ^-9
6th surface K = -0.954
A ₄ = 1.31409 × 10 ^-3
A ₆ = 2.98474 × 10 ^-5
A ₈ = 4.67221 × 10 ^-6
A ₁₀ = -3.77040 × 10 ^-7
Surface 9 K = 0.000
A ₄ = 3.73309 × 10 ^-3
A ₆ = 5.31664 × 10 ^-4
A ₈ = -3.88576 × 10 ^-5
A ₁₀ = 1.32383 × 10 ^-5
10th surface K = 0.000
A ₄ = -2.15582 × 10 ^-4
A ₆ = 2.64093 × 10 ^-5
A ₈ = 0
A ₁₀ = 0
Zoom data (∞)
WE ST TE
f (mm) 6.615 12.686 19.116
F _NO 3.48 4.58 5.79
d ₄ 13.28 4.15 0.90
d ₉ 3.16 3.09 3.96
d ₁₁ 5.29 9.64 13.97.

Example 17
r ₁ = 23.249 d ₁ = 1.00 n _d1 = 1.80610 ν _d1 = 40.92
r ₂ = 4.545 (aspherical surface) d ₂ = 1.68
r ₃ = 6.745 d ₃ = 1.62 n _d2 = 2.00069 ν _d2 = 25.46
r ₄ = 10.000 d ₄ = (variable)
r ₅ = ∞ (aperture) d ₅ = -0.50
r ₆ = 4.591 (aspherical surface) d ₆ = 1.98 n _d3 = 1.80610 ν _d3 = 40.92
r ₇ = 50.000 d ₇ = 0.55 n _d4 = 1.74000 ν _d4 = 28.30
r ₈ = 3.147 d ₈ = 1.75 n _d5 = 1.58313 ν _d5 = 59.38
r ₉ = 8.300 (aspherical surface) d ₉ = (variable)
r ₁₀ = 11.436 (aspherical surface) d ₁₀ = 1.20 n _d6 = 1.52511 ν _d6 = 56.22
r ₁₁ = 85.514 d ₁₁ = (variable)
r ₁₂ = ∞ d ₁₂ = 0.50 n _d7 = 1.51633 ν _d7 = 64.14
r ₁₃ = ∞ d ₁₃ = 0.50
r ₁₄ = ∞ d ₁₄ = 0.50 n _d8 = 1.51633 ν _d8 = 64.14
r ₁₅ = ∞ d ₁₅ = 0.40
r ₁₆ = ∞ (image plane)
Aspheric coefficient 2nd surface K = -1.069
A ₄ = 9.82367 × 10 ^-4
A ₆ = 6.13229 × 10 ^-6
A ₈ = 4.16082 × 10 ^-7
A ₁₀ = -1.47859 × 10 ^-9
6th surface K = -1.111
A ₄ = 1.36092 × 10 ^-3
A ₆ = 2.46840 × 10 ^-5
A ₈ = 1.69262 × 10 ^-6
A ₁₀ = -1.16420 × 10 ^-7
Surface 9 K = 0.000
A ₄ = 3.53310 × 10 ^-3
A ₆ = 2.64589 × 10 ^-4
A ₈ = 2.99098 × 10 ^-5
A ₁₀ = 2.87001 × 10 ^-6
10th surface K = 0.000
A ₄ = -2.73474 × 10 ^-4
A ₆ = 2.44609 × 10 ^-5
A ₈ = 0
A ₁₀ = 0
Zoom data (∞)
WE ST TE
f (mm) 6.621 12.744 19.118
F _NO 3.44 4.57 5.76
d ₄ 12.85 4.04 0.90
d ₉ 3.39 3.50 4.15
d ₁₁ 5.08 9.49 13.99.

  Aberration diagrams of Examples 1 to 17 at the time of focusing on an object point at infinity are shown in FIGS. In these aberration diagrams, (a) is the wide angle end, (b) is the intermediate state, (c) is the spherical aberration (SA), astigmatism (AS), distortion (DT), and lateral chromatic aberration (CC) at the telephoto end. ). In each figure, “FIY” indicates the maximum image height.

  Next, the angle of view, the parameter values regarding the conditional expressions (1) to (B-2), the lens type, and the like in each of the above embodiments will be shown.

Conditional Expression / Power Arrangement Example 1 Example 2 Example 3 Example 4 Example 5 Example 6
(1) 0.495 0.507 0.471 0.557 0.508 0.521
(2) 0.18 0.22 0.02 0.15 0.07 0.04
(3) 1.33 1.60 1.44 1.31 1.26 1.21
(4)------
(5) 1.84 5.18 2.11 3.83 2.76 2.33
(6)------
(7) 0.041 0.044 0.050 0.041 0.041 0.034
(A) 2.89 2.90 2.91 2.90 2.90 2.88
(B-1) − − − − − −
(B-2) -3.15 -1.26 -2.22 -0.95 -1.76 -1.71
Group Type Negative Positive Negative Negative Positive Negative Negative Positive Negative Negative Positive Negative Negative Positive Negative Negative Positive Negative Second Group Junction Configuration Positive Negative Positive Positive Negative Positive Negative Positive Positive Negative Positive Positive Negative Negative Positive Negative Negative

Conditional Expression / Power Arrangement Example 7 Example 8 Example 9 Example 10 Example 11 Example 12
(1) 0.505 0.481 0.496 0.487 0.427 0.476
(2) 0.15 0.21 0.04 0.06 0.00 0.33
(3) 1.42 1.62 1.60 1.55 1.62 1.58
(4)-3.41 6.29 5.30 6.09 4.22
(5) 4.41 − − − − −
(6)-0.066 0.057 0.057 0.062 0.076
(7) 0.034 − − − − −
(A) 2.88 2.89 2.88 2.88 2.90 2.87
(B-1)-0.94 0.65 0.71 0.67 0.81
(B-2) -1.25-----
Group type Negative positive negative Negative positive positive Negative positive positive Negative positive positive Negative positive positive Second group junction configuration Positive negative positive Positive negative positive Positive negative positive Positive negative positive Positive negative positive Positive negative

Conditional Expression / Power Arrangement Example 13 Example 14 Example 15 Example 16 Example 17
(1) 0.473 0.511 0.410 0.435 0.437
(2) 0.41 0.00 0.10 0.12 0.12
(3) 1.63 1.67 1.52 1.56 1.58
(4) 3.71 13.10 4.54 3.78 3.78
(5)-----
(6) 0.071 0.061 0.063 0.063 0.063
(7)-----
(A) 2.88 2.89 2.89 2.89 2.89
(B-1) 0.88 0.37 0.79 0.88 0.88
(B-2)-----
Group type Negative positive positive Negative positive positive Negative positive positive Negative positive positive Negative positive positive Second group junction configuration Positive negative positive Positive negative positive Positive negative positive Positive negative positive
.

  35 to 37 are conceptual diagrams of the configuration of the digital camera according to the present invention in which the zoom lens as described above is incorporated in the photographing optical system 41. FIG. FIG. 35 is a front perspective view showing the external appearance of the digital camera 40, FIG. 36 is a rear front view thereof, and FIG. 37 is a schematic cross-sectional view showing the configuration of the digital camera 40. However, in FIGS. 35 and 37, the photographing optical system 41 is not retracted. 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 button 45, a flash 46, a liquid crystal display monitor 47, a focal length change button 61, When the photographing optical system 41 is retracted, including the setting change switch 62, the photographing optical system 41, the finder optical system 43, and the flash 46 are covered with the cover 60 by sliding the cover 60. When the cover 60 is opened and the camera 40 is set to the photographing state, the photographing optical system 41 enters the non-collapsed state shown in FIG. 37. When the shutter button 45 disposed on the upper part of the camera 40 is pressed, the photographing is performed in conjunction therewith. Photographing is performed through the optical system 41, for example, the zoom lens of the first embodiment. An object image formed by the photographic optical system 41 is formed on the imaging surface (photoelectric conversion surface) of the CCD 49 via a low-pass filter F and a cover glass C that are provided with a wavelength band limiting coat. 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 processing means 51. Further, the processing means 51 is connected to a recording means 52 so that a photographed electronic image can be recorded. The recording means 52 may be provided separately from the processing means 51, or may be configured to perform recording / writing electronically using a floppy disk, memory card, MO, or the like. Further, it may be configured as a silver salt camera in which a silver salt film is arranged in place of the CCD 49.

  Further, a finder objective optical system 53 is disposed on the finder optical path 44. The finder objective optical system 53 includes a plurality of lens groups (three groups in the figure) and two prisms, and includes a zoom optical system whose focal length changes in conjunction with the zoom lens of the photographing optical system 41. The object image formed by the finder objective optical system 53 is formed on the field frame 57 of the erecting prism 55 that is an image erecting member. Behind the erecting prism 55, an eyepiece optical system 59 for guiding the erect image to the observer eyeball E is disposed. A cover member 50 is disposed on the exit side of the eyepiece optical system 59.

  In the digital camera 40 configured in this manner, the imaging optical system 41 has a sufficiently wide angle range according to the present invention, and a compact configuration, while the imaging performance is extremely stable at a high zoom ratio and in a full zoom ratio range. Therefore, high performance, downsizing, and wide angle can be realized.

  The present invention may be applied not only to a so-called compact digital camera that captures a general subject as described above, but also to a surveillance camera that requires a wide angle of view and an interchangeable lens camera.

FIG. 2 is a lens cross-sectional view at the wide-angle end (a), the intermediate state (b), and the telephoto end (c) when focusing on an object point at infinity according to the first exemplary embodiment of the zoom lens of the present invention. It is the same figure as FIG. 1 of Example 2 of the zoom lens of this invention. It is the same figure as FIG. 1 of Example 3 of the zoom lens of this invention. It is the same figure as FIG. 1 of Example 4 of the zoom lens of this invention. It is the same figure as FIG. 1 of Example 5 of the zoom lens of this invention. It is the same figure as FIG. 1 of Example 6 of the zoom lens of this invention. It is the same figure as FIG. 1 of Example 7 of the zoom lens of this invention. It is a figure similar to FIG. 1 of Example 8 of the zoom lens of this invention. It is the same figure as FIG. 1 of Example 9 of the zoom lens of this invention. It is a figure similar to FIG. 1 of Example 10 of the zoom lens of this invention. It is the same figure as FIG. 1 of Example 11 of the zoom lens of this invention. It is the same figure as FIG. 1 of Example 12 of the zoom lens of this invention. It is the same figure as FIG. 1 of Example 13 of the zoom lens of this invention. It is the same figure as FIG. 1 of Example 14 of the zoom lens of this invention. It is the same figure as FIG. 1 of Example 15 of the zoom lens of this invention. It is the same figure as FIG. 1 of Example 16 of the zoom lens of this invention. It is a figure similar to FIG. 1 of Example 17 of the zoom lens of this invention. FIG. 6 is an aberration diagram for Example 1 upon focusing on an object point at infinity. FIG. 6 is an aberration diagram for Example 2 upon focusing on an object point at infinity. FIG. 10 is an aberration diagram for Example 3 upon focusing on an object point at infinity. FIG. 10 is an aberration diagram for Example 4 upon focusing on an object point at infinity. FIG. 10 is an aberration diagram for Example 5 upon focusing on an object point at infinity. FIG. 10 is an aberration diagram for Example 6 upon focusing on an object point at infinity. FIG. 10 is an aberration diagram for Example 7 upon focusing on an object point at infinity. FIG. 10 is an aberration diagram for Example 8 upon focusing on an object point at infinity. FIG. 10 is an aberration diagram for Example 9 upon focusing on an object point at infinity. FIG. 10 is an aberration diagram for Example 10 upon focusing on an object point at infinity. FIG. 10 is an aberration diagram for Example 11 upon focusing on an object point at infinity. FIG. 14 is an aberration diagram for Example 12 upon focusing on an object point at infinity. FIG. 14 is an aberration diagram for Example 13 upon focusing on an object point at infinity. FIG. 16 is an aberration diagram for Example 14 upon focusing on an object point at infinity. FIG. 18 is an aberration diagram for Example 15 upon focusing on an object point at infinity. FIG. 16 is an aberration diagram for Example 16 upon focusing on an object point at infinity. FIG. 18 is an aberration diagram for Example 17 upon focusing on an object point at infinity. It is a front perspective view which shows the external appearance of the digital camera by this invention. FIG. 36 is a rear perspective view of the digital camera of FIG. 35. FIG. 36 is a cross-sectional view of the digital camera of FIG. 35.

Explanation of symbols

G1 ... 1st lens group G2 ... 2nd lens group G3 ... 3rd lens group S ... Aperture stop F ... Low pass filter C ... Cover glass I ... Image plane E ... Observer eyeball 40 ... Digital camera 41 ... Shooting optical system 42 ... Optical path for photographing 43 ... finder optical system 44 ... optical path for finder 45 ... shutter button 46 ... flash 47 ... liquid crystal display monitor 49 ... CCD
DESCRIPTION OF SYMBOLS 50 ... Cover member 51 ... Processing means 52 ... Recording means 53 ... Viewfinder objective optical system 55 ... Erect prism 57 ... Field frame 59 ... Eyepiece optical system 60 ... Cover 61 ... Focal length change button 62 ... Setting change switch

Claims (21)

In order from the object side, the first lens group includes a first lens group having a negative refractive power, a second lens group having a positive refractive power, and a third lens group having a positive or negative refractive power. A zoom lens in which an interval between two lens groups changes during zooming, and an interval between the second lens group and the third lens group changes during a focusing operation,
At least the second lens group and the third lens group from the wide-angle end to the telephoto end so that the distance between the first lens group and the second lens group becomes narrower in the telephoto end state than in the wide-angle end state. Move only to the object side when scaling to
The second lens group includes a positive lens and a negative lens, is composed of two or three lenses, and is composed of a cemented lens in which each lens is cemented on the optical axis,
The third lens group consists of one lens,
A zoom lens satisfying the following conditional expressions (1) , (2) ′, and (A):
0.4 <D _ce / D _123G <0.6 (1)
0.00 ≦ (D ₂ (t) −D ₂ (w)) / f _w <0.5 (2) ′
2.5 ≦ f _t / f _w <5.5 (A)
Where D _ce is the thickness of the cemented lens in the second lens group on the optical axis,
D _123G : Value obtained by adding the thickness on the optical axis of each lens group,
D ₂ (w): an air space on the optical axis between the second lens unit and the third lens unit at the wide-angle end,
D ₂ (t): an air interval on the optical axis between the second lens group and the third lens group at the telephoto end,
f _w : Focal length at the wide-angle end of the zoom lens,
f _t : focal length of the zoom lens in the telephoto end state,
It is. In order from the object side, the first lens group includes a first lens group having a negative refractive power, a second lens group having a positive refractive power, and a third lens group having a positive or negative refractive power. A zoom lens in which an interval between two lens groups changes during zooming, and an interval between the second lens group and the third lens group changes during a focusing operation,
At least the second lens group and the third lens group from the wide-angle end to the telephoto end so that the distance between the first lens group and the second lens group becomes narrower in the telephoto end state than in the wide-angle end state. Move only to the object side when scaling to
The second lens group is composed of three lenses of a positive lens, a negative lens, and a positive lens in order from the object side, and a cemented lens in which each lens is cemented on the optical axis.
The third lens group consists of one lens,
A zoom lens satisfying the following conditional expression (1):
0.4 <D _ce / D _123G <0.6 (1)
However, D _ce : Thickness on the optical axis of the cemented lens in the second lens group,
D _123G : Value obtained by adding the thickness on the optical axis of each lens group,
It is. In order from the object side, the lens unit includes three lens groups, a first lens group having a negative refractive power, a second lens group having a positive refractive power, and a third lens group having a positive refractive power. A zoom lens in which an interval between the second lens group and the third lens group is changed at the time of zooming, and an interval between the second lens group and the third lens group is changed during a focusing operation;
At least the second lens group and the third lens group from the wide-angle end to the telephoto end so that the distance between the first lens group and the second lens group becomes narrower in the telephoto end state than in the wide-angle end state. Move only to the object side when scaling to
The second lens group includes a positive lens and a negative lens, is composed of two or three lenses, and is composed of a cemented lens in which each lens is cemented on the optical axis,
The third lens group is composed of one positive lens,
The third lens group moves for focusing;
A zoom lens satisfying the following conditional expressions (1) and (4):
0.4 <D _ce / D _123G <0.6 (1)
3.0 <f _Three / F _w <15.0 (4)
However, D _ce : Thickness on the optical axis of the cemented lens in the second lens group,
D _123G : Value obtained by adding the thickness on the optical axis of each lens group,
f _Three : Focal length of the third lens group,
f _w : Focal length at the wide-angle end of the zoom lens,
It is. In order from the object side, the lens unit includes three lens groups, a first lens group having a negative refractive power, a second lens group having a positive refractive power, and a third lens group having a positive refractive power. A zoom lens in which an interval between the second lens group and the third lens group is changed at the time of zooming, and an interval between the second lens group and the third lens group is changed during a focusing operation;
At least the second lens group and the third lens group from the wide-angle end to the telephoto end so that the distance between the first lens group and the second lens group becomes narrower in the telephoto end state than in the wide-angle end state. Move only to the object side when scaling to
The second lens group includes a positive lens and a negative lens, is composed of two or three lenses, and is composed of a cemented lens in which each lens is cemented on the optical axis,
The third lens group is composed of one positive lens,
A zoom lens satisfying the following conditional expressions (1) and (6):
0.4 <D _ce / D _123G <0.6 (1)
0.03 <D _3G / F _t <0.09 (6)
However, D _ce : Thickness on the optical axis of the cemented lens in the second lens group,
D _123G : Value obtained by adding the thickness on the optical axis of each lens group,
D _3G : Thickness on the axis of the third lens group,
f _t : Focal length at the telephoto end of the zoom lens,
It is. In order from the object side, the lens unit includes three lens groups, a first lens group having a negative refractive power, a second lens group having a positive refractive power, and a third lens group having a positive refractive power. A zoom lens in which an interval between the second lens group and the third lens group is changed at the time of zooming, and an interval between the second lens group and the third lens group is changed during a focusing operation;
At least the second lens group and the third lens group from the wide-angle end to the telephoto end so that the distance between the first lens group and the second lens group becomes narrower in the telephoto end state than in the wide-angle end state. Move only to the object side when scaling to
The second lens group includes a positive lens and a negative lens, is composed of two or three lenses, and is composed of a cemented lens in which each lens is cemented on the optical axis,
The third lens group is composed of one positive lens,
The third lens group moves for focusing;
A zoom lens satisfying the following conditional expressions (1) and (B-1):
0.4 <D _ce / D _123G <0.6 (1)
0.35 <1-β _3T ² <0.98 (B-1)
However, D _ce : Thickness on the optical axis of the cemented lens in the second lens group,
D _123G : Value obtained by adding the thickness on the optical axis of each lens group,
β _3T : Lateral magnification at the telephoto end of the third lens group,
It is. 6. The zoom lens according to claim 1, wherein only the third lens group moves during focusing. 7 . The zoom lens according to any one of claims 1 to 6, wherein an interval between the second lens group and the third lens group changes at the time of zooming. Any one zoom lens according to claim 1 to 7, wherein the first lens group reciprocates in zooming. Wherein the first lens group comprises, in order from the object side, a negative lens, any one of claims zoom lens of claims 1 to 8, characterized in that it consists of a positive lens. The zoom lens according to any one of claims 1 to 9 , wherein the following conditional expression (2) is satisfied.
−0.005 <(D ₂ (t) −D ₂ (w)) / f _w <0.5 (2)
Where D ₂ (w): the air spacing on the optical axis between the second lens group and the third lens group at the wide-angle end,
D ₂ (t): an air interval on the optical axis between the second lens group and the third lens group at the telephoto end,
f _w : Focal length at the wide-angle end of the zoom lens,
It is. The second lens group includes, in order from the object side, a positive lens, a negative lens, any one of claims 1 to 10, characterized in that it consists of three one cemented lens constructed by a positive lens 1 Zoom lens described in the item. The zoom lens according to any one of claims 1 to 11 , wherein the following conditional expression (3) is satisfied.
1.2 <C _j (t) / _ft <1.8 (3)
Where C _j (t): distance from the entrance surface of the first lens group to the image plane at the telephoto end,
f _t : focal length at the telephoto end of the zoom lens,
It is. The third lens group is moved for focusing, according to any one of claims 1 to 12, wherein the third lens group is a positive lens that satisfies the conditional expression (4) below Zoom lens.
3.0 <f ₃ / f _w <15.0 (4)
Where f _{3 is} the focal length of the third lens group,
f _w : Focal length at the wide-angle end of the zoom lens,
It is. The third lens group is moved for focusing, according to claim 1 or 2, wherein the zoom lens, wherein the third lens group is a negative lens that satisfies a conditional expression (5).
1.5 <| f ₃ / f _w | <15.0 (5)
Where f _{3 is} the focal length of the third lens group,
f _w : Focal length at the wide-angle end of the zoom lens,
It is. The zoom lens according to any one of claims 1 to 13 , wherein the third lens group is a positive lens that satisfies the following conditional expression (6).
0.03 <D _3G / _ft <0.09 (6)
D _3G : Thickness on the axis of the third lens group,
f _t : focal length of the zoom lens in the telephoto end state,
It is. The zoom lens according to claim 1 , wherein the third lens group is a negative lens that satisfies the following conditional expression (7).
0.01 <D _3G / _ft <0.09 (7)
D _3G : Thickness on the axis of the third lens group,
f _t : focal length of the zoom lens in the telephoto end state,
It is. The third lens group moves for focusing, and the third lens group is a positive lens that satisfies the following conditional expression (B-1): 16 . The zoom lens according to item 1.
0.35 <1-β _3T ² <0.98 (B-1)
Where β _3T : lateral magnification at the telephoto end of the third lens group,
It is. The third lens group is moved for focusing, and the third lens group is a negative lens that satisfies the following conditional expression (B-2) : 17 . Any one of the zoom lenses.
−3.5 <1-β _3T ² <−0.6 (B-2)
Where β _3T : lateral magnification at the telephoto end of the third lens group,
It is. Any one of claims zoom lens according to claim 1 to 18, characterized in that the following condition is satisfied.
2.5 ≦ f _t / f _w <5.5 (A)
Where f _t : focal length of the zoom lens in the telephoto end state,
f _w : Focal length at the wide-angle end of the zoom lens,
It is. Together is disposed immediately before the second lens group, said any one of claims 1 to 19, characterized in that it comprises an aperture stop that moves in the second lens group and integrally during zooming Zoom lens. A zoom lens according to any one of claims 1 20, arranged on the image side of the zoom lens, an imaging apparatus characterized by comprising an imaging device that converts an optical image into an electrical signal.

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