JP2011008063A - Imaging optical system and electronic imaging apparatus having the same - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide an imaging optical system having superior imaging performance over the full zoom range and having a wide viewing angle at the wide angle end and a high zoom ratio, by satisfactorily correcting chromatic aberration, and to provide an electronic imaging apparatus that uses the system.SOLUTION: In the electronic imaging apparatus having the imaging optical system and an imaging device, the imaging optical system has, in the order starting from the object side to the image side, a first lens group having positive refractive powers; a second lens group having negative refractive powers and an image-side lens group having positive refractive power, wherein a space between the first lens group and the second lens group changes at the zooming. A cemented optical element D is provided in the first lens group which is constituted so that a dioptric element (A) having positive refractive power is located between an object side optical element B and an image-side optical element C. The imaging optical system satisfies the conditional expressions (4-1), (4-2) and (4-3): (4-1) are νd<30, (4-2): 0.54<θgF<0.9, and (4-3): 0.387<(Tnglw(0.7)/Tbasw(0.7))/(Tngl(0)/Tbas(0))<0.525, respectively.

Description

  The present invention relates to an imaging optical system used in combination with a solid-state imaging device such as a CCD or a CMOS, and an electronic imaging apparatus having the imaging optical system.

  In recent years, an imaging apparatus such as a digital camera that takes a subject using a solid-state imaging device such as a CCD or a CMOS instead of a silver salt film has become widespread. In a digital camera, a subject is photographed using a solid-state image sensor such as a CCD or a CMOS. An imaging lens that forms an image used in such an imaging apparatus is desired to be a zoom lens (imaging lens) with a high zoom ratio.

  Furthermore, it is desirable that such an imaging lens has a well-corrected aberration related to imaging performance in a single color (spherical aberration, coma aberration, etc.) such as spherical aberration and coma aberration. In addition, it is desired that the white light source is sufficiently corrected for chromatic aberration related to image resolving power and color bleeding.

  On the other hand, it is desired to shorten the total lens length (optical total length). However, as the overall length of the lens is shortened and the entire optical system is made smaller, various aberrations, particularly chromatic aberration, occur, and the imaging performance tends to be lowered.

  In particular, a zoom lens having a high zoom ratio and a long focal length at the telephoto end is required to reduce the secondary spectrum in addition to the primary achromatism to correct chromatic aberration. As a method for reducing the occurrence of such chromatic aberration, a method using an optical material having an abnormal partial dispersion ratio is known (Patent Document 1 to Patent Document 3).

JP 2007-163964 A JP 2006-349947 A JP 2007-298555 A

  A zoom lens used in an image pickup apparatus is desired to have a predetermined zoom ratio, have a wide angle of view at the wide angle end, and be brighter and have higher performance. In order to improve the performance of the zoom lens, it is necessary to correct chromatic aberration well over the entire zoom range.

  Conventionally, in an optical system using an optical material having an anomalous partial dispersion ratio, a wide angle of view at a wide angle end and a low zoom ratio, and a standard angle of view at a wide angle end and a high zoom ratio are achieved. It was. However, a lens having a wide angle of view and a high zoom ratio at the wide angle end has not been achieved.

  In the conventional optical system, the primary achromatic color and the secondary spectrum are reduced. However, an optical system having a wide angle of view and a high zoom ratio at the wide-angle end requires further reduction of the secondary spectrum, but has not been realized.

  The present invention has been made in view of the above, and by arranging an optical element having appropriate dispersion characteristics in an appropriate shape at an appropriate position of an optical system (imaging optical system, zoom lens), chromatic aberration is achieved. Is well corrected, the secondary spectrum is reduced over the entire zoom range, and an imaging optical system having a wide-angle end with a wide angle of view and a high zoom ratio having good imaging performance, and an imaging apparatus using the imaging optical system (electronic imaging) The purpose is to provide a device.

In order to solve the above-described problems and achieve the object, an electronic imaging apparatus according to a first aspect of the present invention is an electronic imaging apparatus having an imaging optical system and an imaging element, wherein the imaging optical system is on the object side. The first lens unit having a positive refractive power, a second lens unit having a negative refractive power, and an image side lens unit having a positive refractive power in order toward the image side, and the first lens during zooming A distance between the first lens group and the second lens group is changed, and a cemented optical element D is provided in the first lens group. The cemented optical element D is an optical element B positioned on the object side and an optical element positioned on the image side. Refractive optical element A having a positive refractive power is positioned between C and C, and satisfies the following conditional expression (4-1) conditional expression (4-2) and conditional expression (4-3) It is characterized by doing.
νd _A <30 (4-1)
0.54 <θgF _A <0.9 (4-2)
0.387 <(Tnglw (0.7) / Tbasw (0.7)) / (Tngl (0) / Tbas (0)) <0.525 (4-3)
here,
νd _A is the Abbe number (nd _A -1) / (nF _A -nC _A ) of the refractive optical element A,
θgF _A is a partial dispersion ratio (ng _A −nF _A ) / (nF _A −nC _A ) of the refractive optical element A,
nd _A , nC _A , nF _A , and ng _A are the refractive indexes of the refractive optical element A with respect to the d-line, C-line, F-line, and g-line,
Tngl (0) is the thickness on the axis of the refractive optical element A,
Tnglw (0.7) is the length that a light beam having a light height of 70% with respect to the maximum light beam height on the image sensor at the wide-angle end passes through the refractive optical element A;
Tbas (0) is the thickness on the axis of the optical element B,
Tbasw (0.7) is the length that a light beam having a light height of 70% with respect to the maximum light beam height on the image sensor at the wide-angle end passes through the optical element B;
It is.

Moreover, it is preferable that the electronic imaging device of the preferable aspect of this invention satisfies the following conditional expressions (2).
｜ fG1 / fG2 ｜ ＞ 6.4 (2)
here,
fG1 is the focal length of the first lens group,
fG2 is the focal length of the second lens group,
It is.

The imaging optical system of the present invention includes, in order from the object side to the image side, a first lens group having a positive refractive power, a second lens group having a negative refractive power, and an image having a positive refractive power. In an imaging optical system that includes a side lens group and the distance between the first lens group and the second lens group changes during zooming, a refractive optical element A having a positive refractive power is provided in the first lens group. It is characterized by satisfying the following conditional expression (4-1), conditional expression (4-2) and conditional expression (2).
νd _A <30 (4-1)
0.54 <θgF _A <0.9 (4-2)
｜ fG1 / fG2 ｜ ＞ 6.4 (2)
here,
nd _A , nC _A , nF _A , and ng _A are the refractive indices of the refractive optical element A with respect to the d-line, C-line, F-line, and g-line,
νd _A is the Abbe number (nd _A -1) / (nF _A -nC _A ) of the refractive optical element A,
θgF _A is a partial dispersion ratio (ng _A −nF _A ) / (nF _A −nC _A ) of the refractive optical element A,
fG1 is the focal length of the first lens group,
fG2 is the focal length of the second lens group,
It is.

Moreover, it is preferable that said imaging optical system satisfies the following conditional expressions (5).
0.4 <θhg _A <1.2 (5)
here,
θhg _A is the partial dispersion ratio (nh _A −ng _A ) / (nF _A −nC _A ) of the h line of the refractive optical element A,
nh _A , nC _A , nF _A , and ng _A are the refractive indexes of the refractive optical element A with respect to the h-line, C-line, F-line, and g-line,
It is.

  The imaging optical system includes, in order from the object side to the image side, a first lens unit having a positive refractive power, a second lens unit having a negative refractive power, an aperture stop, and a first lens unit having a positive refractive power. The first lens group and the second lens group at the telephoto end as compared with the wide-angle end; and a third lens group, a fourth lens group having a positive refractive power, and a fifth lens group having a positive refractive power. The distance between adjacent lens groups is changed so that the distance between the second lens group and the third lens group is small, and the distance between the third lens group and the fourth lens group is large. It is preferable to perform zooming.

Moreover, it is preferable that the distance between the fourth lens group and the fifth lens group in the imaging optical system satisfies the following conditional expression (20).
0 <TG ₄₅ / WG ₄₅ <5 (20)
here,
WG ₄₅ is the distance between the fourth lens group and the fifth lens group at the wide-angle end.
TG ₄₅ is the distance between the fourth lens group and the fifth lens group at the telephoto end.
It is.

Further, the imaging optical system includes an optical element B, and satisfies the following conditional expression (6).
| f _B / f _A |> 0.15 (6)
here,
f _A is the focal length of the refractive optical element A,
f _B is the focal length of the optical element B,
It is.

The imaging optical system preferably includes the optical element B and satisfies the following conditional expression (7).
0 <θgF _B −θgF _BA <0.25 (7)
here,
nd _B , nC _B , nF _B , ng _B are the refractive indices of the optical element B with respect to the d-line, C-line, F-line, and g-line
νd _B is the Abbe number of the optical element B (nd _B -1) / (nF _B -nC _B ),
θgF _B is the partial dispersion ratio (ng _B −nF _B ) / (nF _B −nC _B ) of the optical element B,
θgF _BA is an effective partial dispersion ratio when the refractive optical element A and the optical element B are regarded as one optical element, and is expressed by the following equation:
θgF _BA = f _BA × ν _BA × (θgF _A × φ _A / νd _A + θgF _B × φ _B / νd _B ),
f _BA is the combined focal length of the optical element B and the refractive optical element A, and is represented by the following equation:
1 / f _BA = 1 / f _A + 1 / f _B ,
ν _BA is an Abbe number when the refractive optical element A and the optical element B are regarded as one optical element, and is represented by the following equation:
ν _BA = 1 / (f _BA × (φ _A / νd _A + φ _B / νd _B )),
φ _A is the refractive power of the refractive optical element A (φ _A = 1 / f _A ),
φ _B is the refractive power of the optical element B (φ _B = 1 / f _B ),
φ _BA is the combined refractive power of the optical element B and the refractive optical element A (φ _BA = 1 / f _BA ),
It is.

In addition, the imaging optical system described above is characterized in that the following conditional expression (8) is satisfied.
1.0 <f _A /fG1<8.0 (8)
here,
f _A is the focal length of the refractive optical element A,
fG1 is the focal length of the first lens group,
It is.

The imaging optical system described above is characterized in that the following conditional expression (9) is satisfied.
−25 <(Ra + Rb) / (Ra−Rb) <− 2 (9)
here,
Ra is the radius of curvature of the refractive optical element A on the object side,
Rb is a radius of curvature on the image plane side of the refractive optical element A,
It is.

The electronic imaging device according to the second aspect of the present invention is an electronic imaging device having an imaging optical system and an imaging element, and the imaging optical system has a positive refractive power in order from the object side to the image side. A first lens group, a second lens group having a negative refractive power, and an image side lens group having a positive refractive power, and the distance between the first lens group and the second lens group changes during zooming. Further, the refractive optical element A having a positive refractive power is located in the first lens group, and the following conditional expression (3-2) is satisfied.
0 <(Zb (3.3a) -Za (3.3a)) / (Zb (2.5a) -Za (2.5a)) <0.895 (3-2)
here,
fw is the focal length at the wide-angle end of the imaging optical system,
ft is the focal length at the telephoto end of the imaging optical system,
IH is the maximum image height on the image sensor of the imaging optical system,
Za (h) is the distance in the optical axis direction between the top of the object side surface on the optical axis of the refractive optical element A and the position at the height h on the object side,
Zb (h) is the distance in the optical axis direction between the top of the object side surface on the optical axis of the refractive optical element A and the position at the height h on the image plane side,
a is a value defined by the following equation (3-1):
a = {(IH) ² × log ₁₀ (ft / fw)} / fw (3-1)
It is.

The electronic imaging device according to the third aspect of the present invention is an electronic imaging device having an imaging optical system and an imaging element, wherein the imaging optical system is the imaging optical system according to any one of the above. The following conditional expression (3-2) is satisfied.
0 <(Zb (3.3a) -Za (3.3a)) / (Zb (2.5a) -Za (2.5a)) <0.895 (3-2)
here,
fw is the focal length at the wide-angle end of the imaging optical system,
ft is the focal length at the telephoto end of the imaging optical system,
IH is the maximum image height on the image sensor of the imaging optical system,
Za (h) is the distance in the optical axis direction between the top of the object side surface on the optical axis of the refractive optical element A and the position at the height h on the object side,
Zb (h) is the distance in the optical axis direction between the top of the object side surface on the optical axis of the refractive optical element A and the position at the height h on the image plane side,
a is a value defined by the following equation (3-1):
a = {(IH) ² × log ₁₀ (ft / fw)} / fw (3-1)
It is.

In the electronic imaging apparatus, the imaging optical system includes, in order from the object side to the image side, a first lens group having a positive refractive power, a second lens group having a negative refractive power, and a positive A refractive optical element A having an image side lens group having a refractive power, a distance between the first lens group and the second lens group is changed during zooming, and having a positive refractive power in the first lens group. It is preferable that the following conditional expression (4-1), conditional expression (4-2), and conditional expression (2) are satisfied.
νd _A <30 (4-1)
0.54 <θgF _A <0.9 (4-2)
｜ fG1 / fG2 ｜ ＞ 6.4 (2)
here,
nd _A , nC _A , nF _A , and ng _A are the refractive indices of the refractive optical element A with respect to the d-line, C-line, F-line, and g-line,
νd _A is the Abbe number (nd _A -1) / (nF _A -nC _A ) of the refractive optical element A,
θgF _A is a partial dispersion ratio (ng _A −nF _A ) / (nF _A −nC _A ) of the refractive optical element A,
fG1 is the focal length of the first lens group,
fG2 is the focal length of the second lens group,
It is.

In addition, the above electronic imaging device satisfies any of the following conditional expressions (10-1a), (10-1b), (10-1c), (10-2a), and (10-2b). preferable.
0.3 <Tngl (0) / Tbas (0) <3 (10-1a)
0.2 <Tnglt (0.7) / Tbast (0.7) <2.0 (10-1b)
0.1 <Tnglt (0.9) / Tbast (0.9) <1.4 (10-1c)
0.2 <(Tnglt (0.7) / Tbast (0.7)) / (Tngl (0) / Tbas (0)) <0.85 (10-2a)
0.10 <(Tnglt (0.9) / Tbast (0.9)) / (Tngl (0) / Tbas (0)) <0.75 (10-2b)
here,
Tngl (0) is the thickness on the axis of the refractive optical element A,
Tnglt (0.7) is the length that a light ray having a light height of 70% with respect to the maximum light height on the image sensor at the telephoto end passes through the refractive optical element A;
Tnglt (0.9) is the length that a light beam having a light height of 90% with respect to the maximum light beam height on the image sensor at the telephoto end passes through the refractive optical element A;
Tbas (0) is the thickness on the axis of the optical element B,
Tbast (0.7) is the length that a light beam having a light height of 70% with respect to the maximum light beam height on the image sensor at the telephoto end passes through the optical element B;
Tbast (0.9) is a length that a light beam having a light height of 90% with respect to the maximum light beam height on the image sensor at the telephoto end passes through the optical element B;
It is.

Moreover, it is preferable that the electronic imaging device of the above aspect satisfies the following conditional expression (11a) or conditional expression (11b).
0.5 <(Tnglw (0.7) / (Tngl (0)) <0.95 (11a)
0.3 <(Tnglw (0.9) / (Tngl (0)) <0.85 (11b)
here,
Tngl (0) is the thickness on the axis of the refractive optical element A,
Tnglw (0.7) is a length that a light beam having a light height of 70% with respect to the maximum light beam height on the image sensor at the wide-angle end passes through the refractive optical element A;
Tnglw (0.9) is the length that a light beam having a light height of 90% with respect to the maximum light beam height on the image sensor at the wide-angle end passes through the refractive optical element A;
It is.

Moreover, it is preferable that said electronic imaging device satisfies the following conditional expressions (12a) or (12b).
0.5 <(Tnglt (0.7) / (Tngl (0)) <0.95 (12a)
0.3 <(Tnglt (0.9) / (Tngl (0)) <0.9 (12b)
here,
Tngl (0) is the thickness on the axis of the refractive optical element A,
Tnglt (0.7) is the length that a light ray having a light height of 70% with respect to the maximum light height on the image sensor at the telephoto end passes through the refractive optical element A;
Tnglt (0.9) is the length that a light beam having a light height of 90% with respect to the maximum light beam height on the image sensor at the telephoto end passes through the refractive optical element A;
It is.

In addition, the above electronic imaging apparatus satisfies any of the following conditional expressions (13-1a), (13-1b), (13-1c), and (13-2).
0.3 <Tngl (0) / Tbas (0) <2.5 (13-1a)
0.15 <Tnglw (0.7) / Tbasw (0.7) <1.4 (13-1b)
0 <Tnglw (0.9) / Tbasw (0.9) <0.7 (13-1c)
0 <(Tnglw (0.9) / Tbasw (0.9)) / (Tngl (0) / Tbas (0)) <0.5 (13-2)
here,
Tngl (0) is the thickness on the axis of the refractive optical element A,
Tnglw (0.7) is a length that a light beam having a light height of 70% with respect to the maximum light beam height on the image sensor at the wide-angle end passes through the refractive optical element A;
Tnglw (0.9) is the length that a light beam having a light height of 90% with respect to the maximum light beam height on the image sensor at the wide-angle end passes through the refractive optical element A;
Tbas (0) is the thickness on the axis of the optical element B,
Tbasw (0.7) is the length of light passing through the optical element B at 70% of the maximum light height on the image sensor at the wide-angle end,
Tbasw (0.9) is the length that a light beam having a light height of 90% with respect to the maximum light beam height on the image sensor at the wide angle end passes through the optical element B;
It is.

  An imaging optical system and an electronic imaging device according to the present invention have a secondary spectrum reduced over the entire zoom range, an imaging optical system having a wide angle of view at a wide angle end and a high zoom ratio, and an imaging device using the imaging optical system (electronic imaging). Device) Corrects chromatic aberration, has good imaging performance over the entire zoom range, and can achieve a high zoom ratio while maintaining a wide angle of view at the wide-angle end.

(A) is a wide-angle end, (b) is an intermediate, and (c) is a cross section along an optical axis showing an optical configuration when focusing on an object point at infinity at a telephoto end. FIG. FIG. 4 is a diagram showing spherical aberration, astigmatism, distortion, and lateral chromatic aberration when the imaging optical system according to Example 1 is focused on an object point at infinity, where (a) is a wide angle end, (b) is an intermediate, c) shows the state at the telephoto end. (A) is a wide-angle end, (b) is an intermediate, and (c) is a cross section along the optical axis showing an optical configuration when focusing on an object point at infinity at a telephoto end. FIG. FIG. 6 is a diagram illustrating spherical aberration, astigmatism, distortion, and lateral chromatic aberration when the imaging optical system according to Example 2 is focused on an object point at infinity, where (a) is a wide-angle end, (b) is an intermediate, c) shows the state at the telephoto end. (A) is a wide-angle end, (b) is an intermediate, and (c) is a cross section along the optical axis showing an optical configuration when focusing on an object point at infinity at a telephoto end. FIG. FIG. 10 is a diagram illustrating spherical aberration, astigmatism, distortion, and lateral chromatic aberration when the imaging optical system according to Example 3 is focused on an object point at infinity, where (a) is a wide angle end, (b) is an intermediate, c) shows the state at the telephoto end. (A) is a wide-angle end, (b) is an intermediate, and (c) is a cross section along the optical axis showing an optical configuration when focusing on an object point at infinity at a telephoto end. FIG. FIG. 10 is a diagram showing spherical aberration, astigmatism, distortion, and lateral chromatic aberration when the imaging optical system according to Example 4 is focused on an object point at infinity, where (a) is a wide angle end, (b) is an intermediate, c) shows the state at the telephoto end. (A) is a wide-angle end, (b) is an intermediate, and (c) is a cross section along the optical axis showing an optical configuration when focusing on an object point at infinity at a telephoto end. FIG. FIG. 10 is a diagram illustrating spherical aberration, astigmatism, distortion, and lateral chromatic aberration when the imaging optical system according to Example 5 is focused on an object point at infinity, where (a) is a wide angle end, (b) is an intermediate, c) shows the state at the telephoto end. (A) is a wide-angle end, (b) is an intermediate, and (c) is a cross section along the optical axis showing an optical configuration when focusing on an object point at infinity at a telephoto end. FIG. FIG. 10 is a diagram illustrating spherical aberration, astigmatism, distortion, and chromatic aberration of magnification when the imaging optical system according to Example 6 is focused on an object point at infinity, where (a) is a wide angle end, (b) is an intermediate, c) shows the state at the telephoto end. (A) is a wide-angle end, (b) is an intermediate, and (c) is a cross section along an optical axis showing an optical configuration at the time of focusing on an object point at infinity at a telephoto end. FIG. FIG. 10 is a diagram illustrating spherical aberration, astigmatism, distortion, and chromatic aberration of magnification when the imaging optical system according to Example 7 is focused on an object point at infinity, where (a) is a wide angle end, (b) is an intermediate, c) shows the state at the telephoto end. (A) is a wide-angle end, (b) is an intermediate, and (c) is a cross section along the optical axis showing an optical configuration at the time of focusing on an object point at infinity at the telephoto end. FIG. FIG. 10 is a diagram illustrating spherical aberration, astigmatism, distortion, and lateral chromatic aberration when the imaging optical system according to Example 8 is focused on an object point at infinity, where (a) is a wide-angle end, (b) is a middle, c) shows the state at the telephoto end. (A) is a wide-angle end, (b) is an intermediate, and (c) is a cross section along the optical axis showing an optical configuration when focusing on an object point at infinity at a telephoto end. FIG. FIG. 10 is a diagram illustrating spherical aberration, astigmatism, distortion, and chromatic aberration of magnification when the imaging optical system according to Example 9 is focused on an object point at infinity, (a) is a wide angle end, (b) is an intermediate, c) shows the state at the telephoto end. (A) is the wide-angle end, (b) is the middle, and (c) is a cross section along the optical axis showing the optical configuration when focusing on an object point at infinity at the telephoto end. FIG. FIG. 10 is a diagram illustrating spherical aberration, astigmatism, distortion, and lateral chromatic aberration when the imaging optical system according to Example 10 is focused on an object point at infinity, where (a) is a wide angle end, (b) is an intermediate, c) shows the state at the telephoto end. (A) is a wide-angle end, (b) is an intermediate, and (c) is a cross section along the optical axis showing an optical configuration at the time of focusing on an object point at infinity at the telephoto end. FIG. FIG. 14 is a diagram showing spherical aberration, astigmatism, distortion, and lateral chromatic aberration when the imaging optical system according to Example 11 is focused on an object point at infinity, where (a) is a wide angle end, (b) is an intermediate, c) shows the state at the telephoto end. (A) is the wide-angle end, (b) is the middle, (c) is a cross section along the optical axis showing the optical configuration when focusing on an object point at infinity at the telephoto end. FIG. FIG. 14 is a diagram showing spherical aberration, astigmatism, distortion, and lateral chromatic aberration when the imaging optical system according to Example 12 is focused on an object point at infinity, where (a) is a wide angle end, (b) is an intermediate, c) shows the state at the telephoto end. (A) is the wide-angle end, (b) is the middle, and (c) is a cross section along the optical axis showing the optical configuration when focusing on an object point at infinity at the telephoto end. FIG. FIG. 14 is a diagram illustrating spherical aberration, astigmatism, distortion, and lateral chromatic aberration when the imaging optical system according to Example 13 is focused on an object point at infinity, where (a) is a wide angle end, (b) is an intermediate, c) shows the state at the telephoto end. (A) is the wide-angle end, (b) is the middle, (c) is a cross section along the optical axis showing the optical configuration when focusing on an object point at infinity at the telephoto end. FIG. FIG. 14 is a diagram illustrating spherical aberration, astigmatism, distortion, and lateral chromatic aberration when the imaging optical system according to Example 14 is focused on an object point at infinity, where (a) is a wide angle end, (b) is an intermediate, c) shows the state at the telephoto end. (A) is the wide-angle end, (b) is the middle, and (c) is a cross section along the optical axis showing the optical configuration when focusing on an object point at infinity at the telephoto end. FIG. FIG. 16 is a diagram illustrating spherical aberration, astigmatism, distortion, and lateral chromatic aberration when the imaging optical system according to Example 15 is focused on an object point at infinity, where (a) is a wide angle end, (b) is an intermediate, c) shows the state at the telephoto end. (A) is the wide-angle end, (b) is the middle, and (c) is a cross section along the optical axis showing the optical configuration when focusing on an object point at infinity at the telephoto end. FIG. FIG. 18 is a diagram illustrating spherical aberration, astigmatism, distortion, and lateral chromatic aberration when the imaging optical system according to Example 16 is focused on an object point at infinity, where (a) is a wide-angle end, (b) is a middle, c) shows the state at the telephoto end. It is a front perspective view which shows the external appearance of the digital camera 40 incorporating the imaging optical system by this invention. 2 is a rear perspective view of the digital camera 40. FIG. 2 is a cross-sectional view showing an optical configuration of a digital camera 40. FIG. 1 is a front perspective view of a state in which a cover of a personal computer 300 as an example of an information processing apparatus in which an imaging optical system of the present invention is built as an objective optical system is opened. FIG. 2 is a cross-sectional view of a photographing optical system 303 of a personal computer 300. 2 is a side view of a personal computer 300. FIG. 1A and 1B are diagrams showing a mobile phone as an example of an information processing apparatus in which the imaging optical system of the present invention is built as a photographing optical system, where FIG. 1A is a front view of the mobile phone 400, FIG. ) Is a sectional view of the photographing optical system 405.

Prior to the description of the examples, the imaging apparatus of the present embodiment will be described. For convenience, the operational effects of the imaging optical system will be described first, and then the electronic imaging device will be described.
<Explanation of effective partial dispersion ratio>
First, the Abbe number and the partial dispersion ratio in one optical element are as follows.
νd = (nd-1) / (nF-nC)
θgF = (ng-nF) / (nF-nC)
θhg = (nh-ng) / (nF-nC)
here,
nd, nC, nF, ng, and nh are the optical element wavelength 587.6 nm (d line), wavelength 656.3 nm (C line), wavelength 486.1 nm (F line), wavelength 435.8 nm (g line), wavelength 404.7 nm, respectively. Refractive index for (h-line),
νd is the Abbe number of the optical element,
θgF is the partial dispersion ratio of the optical element with respect to g-line and F-line,
θhg is the partial dispersion ratio of the optical element with respect to h-line and g-line,
It is.

Next, a bonded optical element obtained by bonding two optical elements will be described. The effective partial dispersion ratio θgF ₂₁ when this bonded optical element (two-sheet bonded) is regarded as one optical element can be obtained from the following equation.
θgF ₂₁ = f ₂₁ × ν ₂₁ × (θgF ₁ × φ ₁ / νd ₁ + θgF ₂ × φ ₂ / νd ₂ )… (A)
here,
f ₂₁ is the combined focal length of the two optical elements,
ν ₂₁ is the Abbe number when two optical elements are regarded as one optical element,
θgF ₁ is the partial dispersion ratio of one optical element,
φ ₁ is the power of one optical element,
νd ₁ is the Abbe number of one optical element,
θgF ₂ is the partial dispersion ratio of the other optical element,
φ ₂ is the power of the other optical element,
νd ₂ is the Abbe number of the other optical element,
It is. In addition,
f ₂₁ , ν ₂₁ , φ _1, and φ ₂ are each expressed by the following equations.
1 / f ₂₁ = 1 / f ₁ + 1 / f ₂
ν ₂₁ = 1 / (f ₂₁ × (φ ₁ / νd ₁ + φ ₂ / νd ₂ )),
φ ₁ = 1 / f ₁
φ ₂ = 1 / f ₂
here,
f ₁ is the focal length of one optical element,
f ₂ is the focal length of the other optical element,
It is.
In the following description, the partial dispersion ratio refers to the partial dispersion ratio regarding the g-line and the F-line unless otherwise specified.

The imaging optical system of the first embodiment includes, in order from the object side to the image side, a first lens group having a positive refractive power, a second lens group having a negative refractive power, and an image having a positive refractive power. In an imaging optical system that has a side lens group and the distance between the first lens group and the second lens group changes during zooming, a refractive optical element A having a positive refractive power is located in the first lens group, The following conditional expression (4-1), conditional expression (4-2), and conditional expression (2) are satisfied.
νd _A <30 (4-1)
0.54 <θgF _A <0.9 (4-2)
| FG1 / fG2 |> 6.4 (2)
here,
nd _A , nC _A , nF _A , and ng _A are refractive indexes of the refractive optical element A with respect to the d-line, C-line, F-line, and g-line,
νd _A is the Abbe number (nd _A -1) / (nF _A -nC _A ) of the refractive optical element A,
θgF _A is the partial dispersion ratio (ng _A −nF _A ) / (nF _A −nC _A ) of the refractive optical element A,
fG1 is the focal length of the first lens group,
fG2 is the focal length of the second lens group,
It is.

  In order to achieve high magnification in the imaging optical system in which the first lens group has a positive refractive power, it is necessary to increase the negative refractive power of the second lens group. On the other hand, when the negative refractive power of the second lens group is increased, the aberration generated in the first lens group is magnified after the second lens group. Therefore, the optical performance of the entire optical system is deteriorated. In particular, chromatic aberration worsens at the telephoto end. That is, in order to improve the zoom ratio while maintaining or improving high optical performance, it is important to correct chromatic aberration with the first lens group.

  Therefore, in the imaging optical system of the present embodiment, the refractive optical element A having a positive refractive power is arranged in the first lens group so as to satisfy the conditional expressions (4-1) and (4-2). Yes. By doing so, it is possible to reduce chromatic aberration, particularly the secondary spectrum, generated in the first lens group. Furthermore, by satisfying conditional expression (2), it is possible to achieve a zoom lens having high performance and a high zoom ratio in which chromatic aberration is corrected.

  If the upper limit of conditional expression (4-1) is exceeded, it will be difficult to remove the primary color in the first lens group. As a result, the resolving power at the wide-angle end and the telephoto end decreases, and the performance deteriorates. For this reason, a zoom lens with a high zoom ratio cannot be achieved. If the upper limit of conditional expression (4-2) is exceeded, the correction of the secondary spectrum becomes excessive in the first lens group. For this reason, axial chromatic aberration and lateral chromatic aberration deteriorate at the telephoto end. As a result, color blur due to the secondary spectrum occurs and performance deteriorates, so that a zoom lens with a high zoom ratio cannot be achieved.

  On the other hand, when the lower limit of conditional expressions (4-1) and (4-2) is not reached, the refractive power of the refractive optical element A becomes strong. For this reason, spherical aberration at the telephoto end and chromatic aberration of magnification at the wide-angle end deteriorate. As a result, the resolution is lowered and color blurring occurs and the performance deteriorates, so that it becomes impossible to achieve an imaging optical system with a high zoom ratio.

  If the lower limit of conditional expression (2) is not reached, the ratio of the refractive powers of the first lens group and the second lens group becomes small. Here, the first lens group and the second lens group are lens groups having a zooming action. For this reason, the zoom ratio becomes small. Therefore, it becomes difficult to achieve an imaging optical system having a high zoom ratio. Furthermore, when the ratio of the refractive powers of the first lens group and the second lens group is small, the contribution of the second lens group to the entire imaging optical system is small with respect to the negative refractive power. For this reason, the Petzval sum is positive in the entire imaging optical system. Therefore, it is not desirable because curvature of field occurs and performance is degraded.

  In the imaging optical system of the above embodiment, the cemented optical element D is provided in the first lens group, and the cemented optical element D is composed of an optical element B positioned on the object side and an optical element C positioned on the image side. It is preferable that the refractive optical element A is positioned between them.

Moreover, it is preferable that the imaging optical system of the said embodiment satisfies the following conditional expressions (5). 0.4 <θhg _A <1.2 (5)
here,
θhg _A is the partial dispersion ratio (nh _A −ng _A ) / (nF _A −nC _A ) of the h line of the refractive optical element A,
nC _A , nF _A , and ng _A are refractive indexes of the refractive optical element A with respect to the C line, F line, and g line, respectively.
nh _A is the refractive index of the refractive optical element A with respect to the h-line,
It is.

  Correction of chromatic aberration is necessary to improve the imaging performance. The Abbe number is related to the primary achromatic color, and the partial dispersion ratio is related to the secondary spectrum. In particular, the partial dispersion ratio is related to the occurrence of color bleeding in the imaging performance. Here, the color blur is a phenomenon in which a color that does not exist in the subject is generated at the boundary between the bright and dark areas where the luminance difference is large.

  There are optical materials with optimal Abbe numbers and partial dispersion ratios for primary achromatic and improved color bleeding. By using such an optical material for the refractive optical element, it is possible to improve the imaging performance. However, the color blur cannot be sufficiently corrected only by using a refractive optical element considering only the partial dispersion ratio. Color fringing cannot be corrected sufficiently unless it is a refractive optical element that also considers correction of h-line (404 nm) in combination with Abbe number and partial dispersion ratio.

  Therefore, it is desirable that the imaging optical system of the above embodiment satisfies the conditional expression (5). By satisfying conditional expression (5), it is possible to further reduce color bleeding. As a result, improvement in imaging performance can be achieved in the imaging optical system.

If the upper limit of conditional expression (5) is exceeded, the h line will be excessively corrected. In this case, the color blur is conspicuous, which is not desirable. On the other hand, if the lower limit of conditional expression (5) is not reached, the correction of h-line becomes insufficient. In this case, the color blur is conspicuous, which is not desirable.

  In the imaging optical system of the above embodiment, the first lens group having a positive refractive power, the second lens group having a negative refractive power, an aperture stop, and a positive refractive power are sequentially arranged from the object side to the image side. The third lens group, the fourth lens group having a positive refractive power, and the fifth lens group having a positive refractive power, and the first lens group and the second lens group at the telephoto end as compared with the wide-angle end. Zooming is performed by changing the distance between adjacent lens groups so that the distance between the second lens group and the third lens group is small, and the distance between the third lens group and the fourth lens group is large. Is preferred.

In addition, it is desirable that the distance between the fourth lens group and the fifth lens group in the imaging optical system of the above embodiment satisfies the following conditional expression (20).
0 <TG ₄₅ / WG ₄₅ <5 (20)
here,
WG ₄₅ is the distance between the fourth lens group and the fifth lens group at the wide-angle end.
TG ₄₅ is the distance between the fourth lens group and the fifth lens group at the telephoto end.
It is.

  Exceeding the upper limit of conditional expression (20) is not desirable because it becomes difficult to correct image plane fluctuations associated with zooming and the imaging performance deteriorates. On the other hand, the lower limit of conditional expression (20) is not lower than the lower limit because both the denominator and numerator of conditional expression (20) are positive values.

  As described above, in the imaging optical system according to the above-described embodiment, the optical system includes five groups, and each lens group moves during zooming. By doing in this way, it becomes possible to suppress the fluctuation | variation of the brightness between each zoom state. Furthermore, by correcting mainly chromatic aberration with the first lens group and setting a high zoom ratio with the second lens group, it becomes possible to mainly correct monochromatic aberration after the third lens group.

In addition, it is preferable that the imaging optical system of the above embodiment includes the optical element B and satisfies the following conditional expression (6).
| f _B / f _A |> 0.15 (6)
here,
f _A is the focal length of refractive optical element A,
f _B is the focal length of the optical element B,
It is.

  When the optical element B is provided, in the imaging optical system of the present embodiment, the refractive optical element A is bonded to the optical element B, thereby forming the bonded optical element AB. Further, the optical element C is bonded to the bonded optical element AB, thereby forming the bonded optical element D. Here, in order to reduce the effective partial dispersion ratio of the bonded optical element AB below the partial dispersion ratio of the optical element B, it is desirable to satisfy the conditional expression (6). By satisfying conditional expression (6), the effective partial dispersion ratio of the bonded optical element AB can be made lower than the partial dispersion ratio of the optical element B. Then, by using the cemented optical element D, the secondary spectrum can be further corrected as compared with the case where the optical element B is used alone. For this reason, since the chromatic aberration is improved, the optical performance of the optical system is improved accordingly.

  If the lower limit of conditional expression (6) is not reached, the positive refractive power of the refractive optical element A will decrease. In this case, the amount of decrease in the effective partial dispersion ratio of the two-joint optical element AB with respect to the partial dispersion ratio of the optical element B is reduced. Along with this, the amount of decrease in the effective partial dispersion ratio of the cemented optical element D is reduced. As a result, the difference between the partial dispersion ratio of the optical element B and the effective partial dispersion ratio of the bonding optical element D is reduced. In this case, even if the three-piece junction element D is configured by using the two-piece junction optical element AB, the effect of correcting the secondary spectrum by the three-piece junction element D becomes small, which is not desirable.

In addition, it is preferable that the imaging optical system of the above embodiment includes the optical element B and satisfies the following conditional expression (7).
0 <θgF _B −θgF _BA <0.25 (7)
here,
nd _B , nC _B , nF _B , and ng _B are the refractive indices of the optical element B with respect to the d-line, C-line, F-line, and g-line,
νd _B is the Abbe number (nd _B -1) / (nF _B -nC _B ) of the optical element B,
θgF _B is the partial dispersion ratio (ng _B −nF _B ) / (nF _B −nC _B ) of the optical element B,
θgF _BA is an effective partial dispersion ratio when the refractive optical element A and the optical element B are regarded as one optical element, and is expressed by the following equation:
θgF _BA = f _BA × ν _BA × (θgF _A × φ _A / νd _A + θgF _B × φ _B / νd _B ),
f _BA is the combined focal length of the optical element B and the refractive optical element A, and is expressed by the following equation:
1 / f _BA = 1 / f _A + 1 / f _B ,
ν _BA is an Abbe number when the refractive optical element A and the optical element B are regarded as one optical element, and is represented by the following equation:
ν _BA = 1 / (f _BA × (φ _A / νd _A + φ _B / νd _B )),
φ _A is the refractive power of refractive optical element A (φ _A = 1 / f _A ),
φ _B is the refractive power of optical element B (φ _B = 1 / f _B ),
φ _BA is the combined refractive power of optical element B and refractive optical element A (φ _BA = 1 / f _BA ),
It is.

  When the optical element B is provided, it is preferable to use the optical element B as the two-piece bonded optical element AB rather than using the optical element B alone. By doing so, the secondary spectrum is further corrected. As a result, an improvement in performance accompanying improvement in color blur is achieved.

Exceeding the upper limit of conditional expression (7) is not desirable because color blur occurs due to overcorrection of the secondary spectrum. On the other hand, if the lower limit of conditional expression (7) is not reached, the effective partial dispersion ratio (θgF _BA ) of the two-joint optical element AB becomes larger than the partial dispersion ratio (θgF _B ) of the optical element B alone. That is, the secondary spectrum is generated by the refractive optical element A. Therefore, as a result, the color blur increases before joining, which is not desirable.

Moreover, it is preferable that the imaging optical system of the said embodiment satisfies the following conditional expressions (8).
1.0 <f _A /fG1<8.0 (8)
here,
f _A is the focal length of the refractive optical element A,
fG1 is the focal length of the first lens group,
It is.

  In order to maintain or improve high performance in the imaging optical system, it is important to sufficiently correct chromatic aberration in the first lens group. In particular, it is desirable to satisfy the conditional expression (8) in order to correct the color blur by correcting the secondary spectrum with the first lens group.

  If the upper limit of conditional expression (8) is exceeded, the refractive power of the refractive optical element A becomes weak. In this case, it becomes difficult to lower the effective partial dispersion ratio of the cemented optical element D (or the two-piece bonded optical element AB) than the partial dispersion ratio of the optical element B alone. As a result, color blur due to insufficient correction of the secondary spectrum occurs, which is not desirable.

  On the other hand, when the lower limit of conditional expression (8) is not reached, the refractive power of the refractive optical element A becomes strong. In this case, the effective partial dispersion ratio of the bonded optical element D (or the two-piece bonded optical element AB) can be made lower than the partial dispersion ratio of the optical element B alone. However, this will overcorrect the secondary spectrum. That is, the secondary spectrum is generated by the refractive optical element A. This is undesirable because color blur increases as a result.

Moreover, it is preferable that the imaging optical system of the said embodiment satisfies the following conditional expressions (9).
−25 <(Ra + Rb) / (Ra−Rb) <− 2 (9)
here,
Ra is the radius of curvature of the object side of refractive optical element A,
Rb is the radius of curvature of the refractive optical element A on the image plane side,
It is.

  When the upper limit of conditional expression (9) is exceeded, spherical aberration increases in the negative direction at the telephoto end. If the lower limit of conditional expression (9) is not reached, the spherical aberration increases in the positive direction. In either case, the imaging performance deteriorates, which is not desirable.

The electronic imaging apparatus according to the first embodiment of the present invention is an electronic imaging apparatus having an imaging optical system and an imaging element. The imaging optical system has a positive refractive power in order from the object side to the image side. One lens group, a second lens group having a negative refractive power, and an image side lens group having a positive refractive power. The distance between the first lens group and the second lens group changes during zooming. A cemented optical element D is provided in one lens group. The cemented optical element D includes a refractive optical element A having a positive refractive power between the optical element B positioned on the object side and the optical element C positioned on the image side. The following conditional expression (4-1), conditional expression (4-2), and conditional expression (4-3) are satisfied.
νd _A <30 (4-1)
0.54 <θgF _A <0.9 (4-2)
0.387 <(Tnglw (0.7) / Tbasw (0.7)) / (Tngl (0) / Tbas (0)) <0.525 (4-3)
here,
νd _A is the Abbe number (nd _A -1) / (nF _A -nC _A ) of the refractive optical element A,
θgF _A is the partial dispersion ratio (ng _A −nF _A ) / (nF _A −nC _A ) of the refractive optical element A,
nd _A , nC _A , nF _A , and ng _A are the refractive indices of the refractive optical element A with respect to the d-line, C-line, F-line, and g-line, respectively.
Tngl (0) is the thickness on the axis of refractive optical element A,
Tnglw (0.7) is the length of light passing through the refractive optical element A at 70% of the maximum light height on the image sensor at the wide-angle end.
Tbas (0) is the thickness on the axis of optical element B,
Tbasw (0.7) The length of light passing through the optical element B at 70% of the maximum ray height on the image sensor at the wide-angle end,
It is.

  In a zoom lens in which the first lens group has a positive refractive power, the aberrations generated in the first lens group, particularly the chromatic aberration at the telephoto end are magnified after the second lens group, and the performance deteriorates. That is, in order to maintain or improve high performance, it is important to correct chromatic aberration with the first lens group.

  A refractive optical element A that satisfies the conditional expressions (4-1) and (4-2) and has a positive refractive power when the object-side image side is the air surface is disposed in the first lens group. This can reduce chromatic aberration that occurs in the first lens group.

  Conditional expression (4-1) and conditional expression (4-2) are as described in the description of the imaging optical system of the present embodiment.

  When conditional expression (4-3) is satisfied, axial chromatic aberration and lateral chromatic aberration can be favorably corrected at the wide angle end. Furthermore, axial chromatic aberration and lateral chromatic aberration can be corrected with a good balance.

  If the upper limit of conditional expression (4-3) is exceeded, correction of lateral chromatic aberration will be greater with respect to axial chromatic aberration. In this case, when the correction amount of the lateral chromatic aberration is appropriate, the correction amount of the axial chromatic aberration is insufficient and the axial performance is deteriorated.

  If the lower limit of conditional expression (4-3) is not reached, the correction of lateral chromatic aberration will be small with respect to axial chromatic aberration. In this case, when the correction amount of the longitudinal chromatic aberration is appropriate, the correction amount of the lateral chromatic aberration is insufficient and the off-axis performance is deteriorated.

  The lower limit of conditional expression (4-3) is never negative because the denominator numerator of conditional expression (4-3) is a positive value.

  Further, in the electronic imaging apparatus of the present embodiment, the imaging optical system has the bonding optical element D. The cemented optical element D is composed of three optical elements. Here, the refractive optical element A is positioned between the optical element B and the optical element C to constitute the cemented optical element D. With this configuration, the surface shape of the refractive optical element A is determined by the optical element B and the optical element C. In this case, the surface shape of the refractive optical element A does not change due to environmental changes. Therefore, the cemented optical element D can achieve chromatic aberration correction stably.

Moreover, it is preferable that the electronic imaging device of 1st Embodiment satisfies the following conditional expressions (2).
｜ fG1 / fG2 ｜ ＞ 6.4 (2)
here,
fG1 is the focal length of the first lens group,
fG2 is the focal length of the second lens group,
It is.

  Conditional expression (2) is as described in the description of the imaging optical system of the present embodiment.

In the electronic imaging device according to the second embodiment of the present invention, in the electronic imaging device having an imaging optical system and an imaging element, the imaging optical system has a positive refractive power in order from the object side to the image side. A first lens group, a second lens group having a negative refractive power, and an image side lens group having a positive refractive power, and the distance between the first lens group and the second lens group changes during zooming; The refractive optical element A having positive refractive power is located in the first lens group, and the following conditional expression (3-2) is satisfied.
0 <(Zb (3.3a) -Za (3.3a)) / (Zb (2.5a) -Za (2.5a)) <0.895 (3-2)
here,
fw is the focal length at the wide-angle end of the imaging optical system,
ft is the focal length at the telephoto end of the imaging optical system,
IH is the maximum image height on the image sensor of the imaging optical system,
Za (h) is the distance in the optical axis direction between the top of the object side surface on the optical axis of the refractive optical element A and the position at the height h on the object side,
Zb (h) is the distance in the optical axis direction between the top of the object side surface on the optical axis of the refractive optical element A and the position at the height h on the image plane side,
a is a value defined by the following equation (3-1):
a = {(IH) ² × log ₁₀ (ft / fw)} / fw (3-1)
It is.

  In the electronic imaging device of the present embodiment, the refractive optical element A having a positive refractive power is located in the first lens group. The light beam passing through the refractive optical element A has a different distance and passing position depending on the angle of view and the zoom state. For this reason, even if the shape of the refractive optical element A is constant, the aberration correction effect in the refractive optical element A varies depending on the angle of view and the zoom state. Therefore, in order to obtain a favorable aberration state over the entire zoom range, the shape of the refractive optical element A needs to take into consideration the angle of view, the zoom ratio, and the image height.

If the ray height of the principal ray incident on the maximum image height at a distance L from the stop is a, a is expressed as follows.
a = L × IH / fw
here,
tan (angle of view) = IH / fw,
L∝IH × log ₁₀ (ft / fw)
It can be.
Therefore, when m is a proportional coefficient, a is expressed by the conditional expression (3-1).

  The ray height, the angle of view, the zoom ratio, and the image height have the relationship of conditional expression (3-1). Therefore, it is desirable that the imaging optical system of the present embodiment satisfies the conditional expression (3-2).

  Here, what is required for the first lens group having a positive refractive power is to bring the lateral chromatic aberration at the wide-angle end, the axial chromatic aberration and the spherical aberration at the telephoto end into a favorable aberration state. Thereby, favorable imaging performance can be realized in the imaging optical system.

  If the upper limit of conditional expression (3-2) is exceeded, there is little change in the ratio (medium thickness ratio) between the medium thickness on the axis of the refractive optical element A and the medium thickness on the periphery. For this reason, correction of lateral chromatic aberration at the wide-angle end becomes excessive. Furthermore, correction of axial chromatic aberration and spherical aberration at the telephoto end is insufficient. As a result, it is difficult to achieve good imaging performance, which is not desirable. On the other hand, if the lower limit of conditional expression (3-2) is not reached, the molecular part of conditional expression (3-2) becomes negative. This means that the refractive optical element A cannot realize a physical shape as an optical element.

In the electronic imaging device of the third embodiment, in the electronic imaging device having an imaging optical system and an imaging element, the imaging optical system is any one of the imaging optical systems described above, and the following conditional expression (3 -2) is satisfied.
0 <(Zb (3.3a) -Za (3.3a)) / (Zb (2.5a) -Za (2.5a)) <0.895 (3-2)
here,
fw is the focal length at the wide-angle end of the imaging optical system,
ft is the focal length at the telephoto end of the imaging optical system,
IH is the maximum image height on the image sensor,
Za (h) is the distance in the optical axis direction between the top of the object side surface on the optical axis of the refractive optical element A and the position at the height h on the object side,
Zb (h) is the distance in the optical axis direction between the top of the object side surface on the optical axis of the refractive optical element A and the position at the height h on the image plane side,
a is a value defined by the following equation (3-1):
a = [(IH) ² × log ₁₀ (ft / fw)] / fw (3-1)
It is.

  Conditional expression (3-3) is as already described.

Moreover, it is preferable that the imaging devices of the second and third aspects satisfy the following conditional expression (4-1), conditional expression (4-2), and conditional expression (2).
νd _A <30 (4-1)
0.54 <θgF _A <0.9 (4-2)
｜ G1 / G2 ｜ ＞ 6.4… （2）
here,
nd _A , nC _A , nF _A , and ng _A are refractive indexes of the refractive optical element A with respect to the d-line, C-line, F-line, and g-line,
νd _A is the Abbe number (nd _A -1) / (nF _A -nC _A ) of the refractive optical element A,
θgF _A is the partial dispersion ratio (ng _A −nF _A ) / (nF _A −nC _A ) of the refractive optical element A,
fG1 is the focal length of the first lens group,
fG2 is the focal length of the second lens group,
It is.

  Conditional expression (4-1), conditional expression (4-2), and conditional expression (2) are as already described.

In addition, the above electronic imaging device includes the following conditional expression (10-1a), conditional expression (10-1b), conditional expression (10-1c), conditional expression (10-2a), and conditional expression (10-2b). It is preferable to satisfy any of the following.
0.3 <Tngl (0) / Tbas (0) <3 (10-1a)
0.2 <Tnglt (0.7) / Tbast (0.7) <2.0 (10-1b)
0.1 <Tnglt (0.9) / Tbast (0.9) <1.4 (10-1c)
0.2 <(Tnglt (0.7) / Tbast (0.7)) / (Tngl (0) / Tbas (0)) <0.85 (10-2a)
0.10 <(Tnglt (0.9) / Tbast (0.9)) / (Tngl (0) / Tbas (0)) <0.75 (10-2b)
here,
Tngl (0) is the thickness on the axis of refractive optical element A,
Tnglt (0.7) is the length of light passing through the refractive optical element A at 70% of the maximum light height on the image sensor at the telephoto end.
Tnglt (0.9) is the length of light passing through the refractive optical element A by 90% with respect to the maximum light height on the image sensor at the telephoto end.
Tbas (0) is the thickness on the axis of optical element B,
Tbast (0.7) is the length of light passing through the optical element B at 70% of the maximum light height on the image sensor at the telephoto end.
Tbast (0.9) is the length that a light beam having a light height of 90% with respect to the maximum light beam height on the image sensor at the telephoto end passes through the optical element B;
It is.

  If any one of the conditional expressions (10-1a), (10-1b), (10-1c), (10-2a), and (10-2b) is satisfied, the axis at the telephoto end Upper chromatic aberration and lateral chromatic aberration can be satisfactorily corrected. Furthermore, axial chromatic aberration and lateral chromatic aberration can be corrected with a good balance.

  If the upper limit of conditional expression (10-1a), conditional expression (10-1b), or conditional expression (10-1c) is exceeded, axial chromatic aberration is excessively corrected on the telephoto end axis, and magnification is off-axis. Chromatic aberration is excessively corrected. As a result, the imaging performance of the entire optical system is deteriorated, which is not desirable.

  If the lower limit of conditional expression (10-1a), conditional expression (10-1b), or conditional expression (10-1c) is not reached, axial chromatic aberration is insufficiently corrected on the telephoto end axis, and lateral chromatic aberration is off-axis. Inadequate correction occurs. Further, it is not desirable because the marginal thickness is not taken off the outermost axis and the manufacturing becomes difficult.

  If the upper limit of conditional expression (10-2a) and conditional expression (10-2b) is exceeded, the correction of lateral chromatic aberration will increase with respect to axial chromatic aberration. In this case, when the correction amount of the lateral chromatic aberration is appropriate, the correction amount of the longitudinal chromatic aberration is insufficient. As a result, the on-axis performance deteriorates, which is undesirable.

  If the lower limit of conditional expression (10-2a) and conditional expression (10-2b) is not reached, the correction of lateral chromatic aberration with respect to axial chromatic aberration becomes small. In this case, when the axial chromatic aberration correction amount is appropriate, the lateral chromatic aberration correction amount is insufficient. As a result, off-axis performance is degraded, which is undesirable. In addition, since the lower limit of conditional expression (10-2a) and conditional expression (10-2b) is a positive value in the denominator, it does not become negative.

Moreover, it is preferable that said imaging device satisfies the following conditional expression (11a) or conditional expression (11b).
0.5 <(Tnglw (0.7) / (Tngl (0)) <0.95 (11a)
0.3 <(Tnglw (0.9) / (Tngl (0)) <0.85 (11b)
here,
Tngl (0) is the thickness on the axis of refractive optical element A,
Tnglw (0.7) is the length that a light beam having a light height of 70% passes through the refractive optical element A with respect to the maximum light beam height on the image sensor at the wide angle end.
Tnglw (0.9) is the length that a light beam having a light height of 90% passes through the refractive optical element A with respect to the maximum light beam height on the image sensor at the wide angle end.
It is.

  When conditional expression (11a) and conditional expression (11b) are satisfied, axial chromatic aberration and lateral chromatic aberration can be corrected well at the wide angle end. Furthermore, axial chromatic aberration and lateral chromatic aberration can be corrected with a good balance.

  When the upper limit of conditional expression (11a) and conditional expression (11b) is exceeded, in refractive optical element A, there is no difference in thickness between the on-axis and off-axis thickness. In this case, the correction of the lateral chromatic aberration is excessive with respect to the longitudinal chromatic aberration. As a result, the imaging performance of the entire optical system is deteriorated, which is not desirable. On the other hand, if the lower limit of conditional expression (11a) and conditional expression (11b) is not reached, correction of lateral chromatic aberration will be insufficient for axial chromatic aberration. This is also undesirable because the imaging performance of the entire optical system is deteriorated.

Moreover, it is preferable that said imaging device satisfies the following conditional expressions (12a) or (12b).
0.5 <(Tnglt (0.7) / (Tngl (0)) <0.95 (12a)
0.3 <(Tnglt (0.9) / (Tngl (0)) <0.9 (12b)
here,
Tngl (0) is the thickness on the axis of refractive optical element A,
Tnglt (0.7) is the length of light passing through the refractive optical element A at 70% of the maximum light height on the image sensor at the telephoto end.
Tnglt (0.9) is the length of light passing through the refractive optical element A by 90% with respect to the maximum light height on the image sensor at the telephoto end.
It is.

  When conditional expressions (12a) and (12b) are satisfied, axial chromatic aberration and lateral chromatic aberration can be corrected well at the telephoto end. Furthermore, axial chromatic aberration and lateral chromatic aberration can be corrected with a good balance.

  When the upper limit of conditional expression (12a) and conditional expression (12b) is exceeded, in refractive optical element A, there is no difference in thickness between the on-axis and off-axis thickness. In this case, it is not desirable because correction of lateral chromatic aberration is insufficient for axial chromatic aberration. On the other hand, if the lower limit of the conditional expressions (12a) and (12b) is not reached, the lateral chromatic aberration will be excessively corrected with respect to the axial chromatic aberration. As a result, the imaging performance of the entire optical system is deteriorated, which is not desirable.

Further, the electronic imaging apparatus may satisfy any of the following conditional expression (13-1a), conditional expression (13-1b), conditional expression (13-1c), and conditional expression (13-2). preferable. .
0.3 <Tngl (0) / Tbas (0) <2.5 (13-1a)
0.15 <Tnglw (0.7) / Tbasw (0.7) <1.4 (13-1b)
0 <Tnglw (0.9) / Tbasw (0.9) <0.7 (13-1c)
0 <(Tnglw (0.9) / Tbasw (0.9)) / (Tngl (0) / Tbas (0)) <0.5 (13-2)
here,
Tngl (0) is the thickness on the axis of refractive optical element A,
Tnglw (0.7) is the length that a light beam having a light height of 70% passes through the refractive optical element A with respect to the maximum light beam height on the image sensor at the wide angle end.
Tnglw (0.9) is the length that a light beam having a light height of 90% passes through the refractive optical element A with respect to the maximum light beam height on the image sensor at the wide angle end.
Tbas (0) is the thickness on the axis of optical element B,
Tbasw (0.7) is the length of light passing through the optical element B at 70% of the maximum light height on the image sensor at the wide-angle end.
Tbasw (0.9) is the length that a light beam having a light height of 90% passes through the optical element B with respect to the maximum light beam height on the image sensor at the wide angle end.
It is.

  When conditional expression (13-1a), conditional expression (13-1b), conditional expression (13-1c), and conditional expression (13-2) are satisfied, axial chromatic aberration and lateral chromatic aberration are corrected well at the wide-angle end. be able to. Furthermore, axial chromatic aberration and lateral chromatic aberration can be corrected with a good balance.

  If the upper limit of conditional expression (13-1a), conditional expression (13-1b), or conditional expression (13-1c) is exceeded, axial chromatic aberration is excessively corrected on the wide-angle end axis, and magnification is off-axis. Chromatic aberration is excessively corrected. As a result, the imaging performance of the entire optical system is deteriorated, which is not desirable.

  On the other hand, if the lower limit of conditional expression (13-1a), conditional expression (13-1b), and conditional expression (13-1c) is not reached, the axial chromatic aberration is insufficiently corrected on the wide-angle end axis, and off-axis. Undercorrection of lateral chromatic aberration will occur. Furthermore, it is not desirable because it is difficult to produce a rim on the outermost axis, which makes it difficult to manufacture.

If the upper limit of conditional expression (13-2) is exceeded, correction of lateral chromatic aberration will be greater with respect to axial chromatic aberration. For this reason, when the correction amount of the lateral chromatic aberration is appropriate, the correction amount of the axial chromatic aberration is insufficient and the axial performance is deteriorated, which is not desirable.
Since the lower limit of conditional expression (13-2) is a positive value for both the denominator and numerator of conditional expression (13-2), it does not fall below the lower limit.

  Embodiments of an imaging optical system and an electronic imaging device according to the present invention will be described below in detail with reference to the drawings. Note that the present invention is not limited to the embodiments.

The zoom lens of each embodiment is a photographing lens system used in an image pickup apparatus such as a video camera, a digital camera, or a silver salt film camera.
In the following embodiments, the wide-angle end and the telephoto end refer to zoom positions when the zoom lens unit is positioned at both ends of the range in which the zoom lens unit can move on the optical axis.
Each example is a zoom lens having, in order from the object side to the image side, a first lens group having a positive refractive power, a second lens group having a negative refractive power, and an image side lens group.
In the present invention, the number of lens groups constituting the image side lens group is arbitrary, and it is sufficient to have at least one lens group. That is, the zoom lens according to the present invention only needs to have three or more lens groups.

  From the first example to the ninth example, in order from the object side, a first lens group G1 having a positive refractive power, a second lens group G2 having a negative refractive power, an aperture stop S, and a third lens having a positive refractive power. The lens unit includes a lens group G3, a fourth lens group G4 having a positive refractive power, and a fifth lens group G5 having a positive refractive power. The first lens group G1 includes a negative lens (optical element B), the refractive optical element A having positive refractive power, the positive lens having positive refractive power (optical element C), and one positive lens. ing. With the configuration of the refractive optical element A and the first lens group G1, chromatic aberration correction is effectively performed at the telephoto end.

  The second lens group G2 includes a negative lens, a negative lens, a positive lens, and a negative lens. A high zoom ratio is achieved by the configuration of the second lens group G2.

  The distance between the first lens group G1 and the second lens group G2 is larger at the telephoto end than at the wide-angle end, the distance between the second lens group G2 and the third lens group G3 is small, and the third lens group G3 and the fourth lens group G4. Zooming is performed by changing the interval between adjacent lens groups so that the interval between the lens groups G4 is increased.

  In addition, the fourth lens group G4 corrects the image plane variation due to zooming, and the distance between the fourth lens group G4 and the fifth lens group G5 satisfies the conditional expression (20).

  Next, an image forming optical system according to Example 1 of the present invention will be described. 1A and 1B are cross-sectional views along the optical axis showing the optical configuration of an imaging optical system according to Example 1 of the present invention when focusing on an object point at infinity. FIG. 1A is a wide-angle end, and FIG. The distance state, (c) is a cross-sectional view at the telephoto end.

  FIG. 2 is a diagram illustrating spherical aberration (SA), astigmatism (AS), distortion (DT), and lateral chromatic aberration (CC) when the imaging optical system according to Example 1 is focused on an object point at infinity. , (A) shows the state at the wide angle end, (b) shows the intermediate focal length state, and (c) shows the state at the telephoto end. FIY represents the image height displayed in the aberration diagram. The symbols in the aberration diagrams are the same in the examples described later.

  As shown in FIG. 1, the imaging optical system according to the first embodiment includes, in order from the object side, a first lens group G1, a second lens group G2, an aperture stop S, a third lens group G3, and a fourth lens group. It has a lens group G4 and a fifth lens group G5. In all the following examples, in the lens cross-sectional views, LPF is a low-pass filter, CG is a cover glass, and I is an image pickup surface of an electronic image pickup element.

The first lens group G1 includes, in order from the object side, a negative meniscus lens L1 (optical element B) having a convex surface facing the object side, a positive meniscus lens L2 (refractive optical element A) having a convex surface facing the object side, and the object side. It consists of a cemented lens with a positive meniscus lens L3 (optical element C) with a convex surface and a positive meniscus lens L4 with a convex surface toward the object side, and has a positive refractive power as a whole. Here, the partial dispersion ratio (θgF _A ) of the refractive optical element A of the cemented lens of the first lens group G1 is 0.668. The Abbe number (νd _A ) of the refractive optical element A is 23.38.

  In order from the object side, the second lens group G2 includes a negative meniscus lens L5 having a convex surface directed toward the object side, a cemented lens of a biconcave negative lens L6 and a biconvex positive lens L8, and a negative lens having a convex surface directed toward the image side. And a meniscus lens L9, which has a negative refractive power as a whole. In all the following examples, L7 is a bonding layer.

  The third lens group G3 includes, in order from the object side, a biconvex positive lens L10, a negative meniscus lens L11 with a convex surface facing the object side, a biconvex positive lens L12, and a negative meniscus lens L13 with a convex surface facing the object side. And has a positive refractive power as a whole.

  The fourth lens group G4 includes, in order from the object side, a cemented lens of a biconvex positive lens L14 and a biconcave negative lens L16, and has a positive refractive power as a whole. In all the following examples, L15 is a bonding layer.

  The fifth lens group G5 includes, in order from the object side, a biconvex positive lens L17. The fifth lens group G5 has a positive refractive power as a whole.

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

  The aspheric surfaces are the image side surface of the negative meniscus lens L9 on the image side of the second lens group G2, the object side surface of the biconvex positive lens L10 on the object side of the third lens group G3, and the negative meniscus lens on the image side. It is provided on six surfaces, that is, both surfaces of L13 and both surfaces of the biconvex positive lens L17 of the fifth lens group G5.

  Next, an image forming optical system according to Example 2 of the present invention will be described. FIGS. 3A and 3B are cross-sectional views along the optical axis showing the optical configuration of the imaging optical system according to Example 2 of the present invention when focusing on an object point at infinity. FIG. 3A is a wide-angle end, and FIG. The distance state, (c) is a cross-sectional view at the telephoto end.

  4A and 4B are diagrams illustrating spherical aberration, astigmatism, distortion, and lateral chromatic aberration when the imaging optical system according to Example 2 is focused on an object point at infinity. FIG. 4A illustrates a wide-angle end, and FIG. Intermediate focal length state, (c) shows the state at the telephoto end.

  As shown in FIG. 3, the imaging optical system according to the second embodiment includes, in order from the object side, the first lens group G1, the second lens group G2, the aperture stop S, the third lens group G3, and the fourth lens group. It has a lens group G4 and a fifth lens group G5.

The first lens group G1 includes, in order from the object side, a negative meniscus lens L1 (optical element B) having a convex surface facing the object side, a positive meniscus lens L2 (refractive optical element A) having a convex surface facing the object side, and the object side. It consists of a cemented lens with a positive meniscus lens L3 (optical element C) with a convex surface and a positive meniscus lens L4 with a convex surface toward the object side, and has a positive refractive power as a whole. Here, the partial dispersion ratio (θgF _A ) of the refractive optical element A of the cemented lens of the first lens group G1 is 0.668. The Abbe number (νd _A ) of the refractive optical element A is 23.38.

  In order from the object side, the second lens group G2 includes a negative meniscus lens L5 having a convex surface directed toward the object side, a cemented lens of a biconcave negative lens L6 and a biconvex positive lens L8, and a negative lens having a convex surface directed toward the image side. And a meniscus lens L9, which has a negative refractive power as a whole. L7 is a joint surface.

  The third lens group G3 includes, in order from the object side, a biconvex positive lens L10, a negative meniscus lens L11 with a convex surface facing the object side, a biconvex positive lens L12, and a negative meniscus lens L13 with a convex surface facing the object side. And has a positive refractive power as a whole.

  The fourth lens group G4 includes, in order from the object side, a cemented lens of a biconvex positive lens L14 and a biconcave negative lens L16, and has a positive refractive power as a whole. L15 is a joint surface.

  The fifth lens group G5 includes, in order from the object side, a biconvex positive lens L17. The fifth lens group G5 has a positive refractive power as a whole.

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

  The aspheric surfaces are the image side surface of the negative meniscus lens L9 on the image side of the second lens group G2, the object side surface of the biconvex positive lens L10 on the object side of the third lens group G3, and the negative meniscus lens on the image side. It is provided on six surfaces, that is, both surfaces of L13 and both surfaces of the biconvex positive lens L17 of the fifth lens group G5.

  Next, an image forming optical system according to Example 3 of the present invention will be described. FIGS. 5A and 5B are cross-sectional views along the optical axis showing the optical configuration of the imaging optical system according to Example 3 of the present invention when focusing on an object point at infinity. FIG. 5A is a wide-angle end, and FIG. The distance state, (c) is a cross-sectional view at the telephoto end.

  6A and 6B are diagrams showing spherical aberration, astigmatism, distortion aberration, and chromatic aberration of magnification when the imaging optical system according to Example 3 is focused on an object point at infinity. FIG. 6A is a wide-angle end, and FIG. Intermediate focal length state, (c) shows the state at the telephoto end.

  As shown in FIG. 5, the imaging optical system of Example 3 includes, in order from the object side, the first lens group G1, the second lens group G2, the aperture stop S, the third lens group G3, and the fourth lens group. It has a lens group G4 and a fifth lens group G5.

The first lens group G1 includes, in order from the object side, a negative meniscus lens L1 (optical element B) having a convex surface facing the object side, a positive meniscus lens L2 (refractive optical element A) having a convex surface facing the object side, and the object side. It consists of a cemented lens with a positive meniscus lens L3 (optical element C) with a convex surface and a positive meniscus lens L4 with a convex surface toward the object side, and has a positive refractive power as a whole. Here, the partial dispersion ratio (θgF _A ) of the refractive optical element A of the cemented lens of the first lens group G1 is 0.668. The Abbe number (νd _A ) of the refractive optical element A is 23.38.

  In order from the object side, the second lens group G2 includes a negative meniscus lens L5 having a convex surface directed toward the object side, a cemented lens of a biconcave negative lens L6 and a biconvex positive lens L8, and a negative lens having a convex surface directed toward the image side. And a meniscus lens L9, which has a negative refractive power as a whole. L7 is a joint surface.

  The third lens group G3 includes, in order from the object side, a biconvex positive lens L10, a negative meniscus lens L11 with a convex surface facing the object side, a biconvex positive lens L12, and a negative meniscus lens L13 with a convex surface facing the object side. And has a positive refractive power as a whole.

  The fourth lens group G4 includes, in order from the object side, a cemented lens of a biconvex positive lens L14 and a biconcave negative lens L16, and has a positive refractive power as a whole. L15 is a joint surface.

  The fifth lens group G5 includes, in order from the object side, a biconvex positive lens L17. The fifth lens group G5 has a positive refractive power as a whole.

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

  The aspheric surfaces are the image side surface of the negative meniscus lens L9 on the image side of the second lens group G2, the object side surface of the biconvex positive lens L10 on the object side of the third lens group G3, and the negative meniscus lens on the image side. It is provided on six surfaces, that is, both surfaces of L13 and both surfaces of the biconvex positive lens L17 of the fifth lens group G5.

  Next, an image forming optical system according to Example 4 of the present invention will be described. 7A and 7B are cross-sectional views along the optical axis showing the optical configuration of the imaging optical system according to Example 4 of the present invention when focusing on an object point at infinity. FIG. 7A is a wide-angle end, and FIG. Distance state, (c) is a cross-sectional view at the telephoto end.

  8A and 8B are diagrams illustrating spherical aberration, astigmatism, distortion, and lateral chromatic aberration when the imaging optical system according to Example 4 is focused on an object point at infinity. FIG. 8A is a wide-angle end, and FIG. Intermediate focal length state, (c) shows the state at the telephoto end.

  As shown in FIG. 7, the imaging optical system of Example 4 includes, in order from the object side, the first lens group G1, the second lens group G2, the aperture stop S, the third lens group G3, and the fourth lens group. It has a lens group G4 and a fifth lens group G5.

The first lens group G1 includes, in order from the object side, a negative meniscus lens L1 (optical element B) having a convex surface facing the object side, a positive meniscus lens L2 (refractive optical element A) having a convex surface facing the object side, and the object side. It consists of a cemented lens with a positive meniscus lens L3 (optical element C) with a convex surface and a positive meniscus lens L4 with a convex surface toward the object side, and has a positive refractive power as a whole. Here, the partial dispersion ratio (θgF _A ) of the refractive optical element A of the cemented lens of the first lens group G1 is 0.668. The Abbe number (νd _A ) of the refractive optical element A is 23.38.

  In order from the object side, the second lens group G2 includes a negative meniscus lens L5 having a convex surface directed toward the object side, a cemented lens of a biconcave negative lens L6 and a biconvex positive lens L8, and a negative lens having a convex surface directed toward the image side. And a meniscus lens L9, which has a negative refractive power as a whole. L7 is a joint surface.

  The third lens group G3 includes, in order from the object side, a biconvex positive lens L10, a negative meniscus lens L11 with a convex surface facing the object side, a biconvex positive lens L12, and a negative meniscus lens L13 with a convex surface facing the object side. And has a positive refractive power as a whole.

  The fourth lens group G4 includes, in order from the object side, a cemented lens of a biconvex positive lens L14 and a biconcave negative lens L16, and has a positive refractive power as a whole. L15 is a joint surface.

  The fifth lens group G5 includes, in order from the object side, a biconvex positive lens L17. The fifth lens group G5 has a positive refractive power as a whole.

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

  The aspheric surfaces are the image side surface of the negative meniscus lens L9 on the image side of the second lens group G2, the object side surface of the biconvex positive lens L10 on the object side of the third lens group G3, and the negative meniscus lens on the image side. It is provided on six surfaces, that is, both surfaces of L13 and both surfaces of the biconvex positive lens L17 of the fifth lens group G5.

  Next, an image forming optical system according to Example 5 of the present invention will be described. 9A and 9B are cross-sectional views along the optical axis showing the optical configuration of the imaging optical system according to Example 5 of the present invention when focusing on an object point at infinity. FIG. 9A is a wide-angle end, and FIG. The distance state, (c) is a cross-sectional view at the telephoto end.

  10A and 10B are diagrams illustrating spherical aberration, astigmatism, distortion, and lateral chromatic aberration when the imaging optical system according to Example 5 is focused on an object point at infinity. FIG. 10A is a wide-angle end, and FIG. Intermediate focal length state, (c) shows the state at the telephoto end.

  As shown in FIG. 9, the imaging optical system according to the fifth embodiment includes, in order from the object side, the first lens group G1, the second lens group G2, the aperture stop S, the third lens group G3, and the fourth lens group. It has a lens group G4 and a fifth lens group G5.

The first lens group G1 includes, in order from the object side, a negative meniscus lens L1 (optical element B) having a convex surface facing the object side, a positive meniscus lens L2 (refractive optical element A) having a convex surface facing the object side, and the object side. It consists of a cemented lens with a positive meniscus lens L3 (optical element C) with a convex surface and a positive meniscus lens L4 with a convex surface toward the object side, and has a positive refractive power as a whole. Here, the partial dispersion ratio (θgF _A ) of the refractive optical element A of the cemented lens of the first lens group G1 is 0.718. The Abbe number (νd _A ) of the refractive optical element A is 17.00.

  In order from the object side, the second lens group G2 includes a negative meniscus lens L5 having a convex surface directed toward the object side, a cemented lens of a biconcave negative lens L6 and a biconvex positive lens L8, and a negative lens having a convex surface directed toward the image side. And a meniscus lens L9, which has a negative refractive power as a whole. L7 is a joint surface.

  The third lens group G3 includes, in order from the object side, a biconvex positive lens L10, a negative meniscus lens L11 with a convex surface facing the object side, a biconvex positive lens L12, and a negative meniscus lens L13 with a convex surface facing the object side. And has a positive refractive power as a whole.

  The fourth lens group G4 includes, in order from the object side, a cemented lens of a biconvex positive lens L14 and a biconcave negative lens L16, and has a positive refractive power as a whole. L15 is a joint surface.

  The fifth lens group G5 includes, in order from the object side, a biconvex positive lens L17. The fifth lens group G5 has a positive refractive power as a whole.

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

  The aspheric surfaces are the image side surface of the negative meniscus lens L9 on the image side of the second lens group G2, the object side surface of the biconvex positive lens L10 on the object side of the third lens group G3, and the negative meniscus lens on the image side. It is provided on six surfaces, that is, both surfaces of L13 and both surfaces of the biconvex positive lens L17 of the fifth lens group G5.

  Next, an image forming optical system according to Example 6 of the present invention will be described. 11A and 11B are cross-sectional views along the optical axis showing the optical configuration of the imaging optical system according to Example 6 of the present invention when focusing on an object point at infinity. FIG. 11A is a wide-angle end, and FIG. The distance state, (c) is a cross-sectional view at the telephoto end.

  12A and 12B are diagrams illustrating spherical aberration, astigmatism, distortion, and lateral chromatic aberration when the imaging optical system according to Example 6 is focused on an object point at infinity. FIG. 12A illustrates a wide-angle end, and FIG. Intermediate focal length state, (c) shows the state at the telephoto end.

  As shown in FIG. 11, the imaging optical system of Example 6 includes, in order from the object side, the first lens group G1, the second lens group G2, the aperture stop S, the third lens group G3, and the fourth lens group. It has a lens group G4 and a fifth lens group G5.

The first lens group G1 includes, in order from the object side, a negative meniscus lens L1 (optical element B) having a convex surface facing the object side, a positive meniscus lens L2 (refractive optical element A) having a convex surface facing the object side, and a biconvex positive The lens is composed of a cemented lens with the lens L3 (optical element C) and a positive meniscus lens L4 having a convex surface facing the object side, and has a positive refractive power as a whole. Here, the partial dispersion ratio (θgF _A ) of the refractive optical element A of the cemented lens of the first lens group G1 is 0.738. The Abbe number (νd _A ) of the refractive optical element A is 15.00.

  In order from the object side, the second lens group G2 includes a negative meniscus lens L5 having a convex surface directed toward the object side, a cemented lens of a biconcave negative lens L6 and a biconvex positive lens L8, and a negative lens having a convex surface directed toward the image side. And a meniscus lens L9, which has a negative refractive power as a whole. L7 is a joint surface.

  The third lens group G3 includes, in order from the object side, a biconvex positive lens L10, a negative meniscus lens L11 with a convex surface facing the object side, a biconvex positive lens L12, and a negative meniscus lens L13 with a convex surface facing the object side. And has a positive refractive power as a whole.

  The fourth lens group G4 includes, in order from the object side, a cemented lens of a biconvex positive lens L14 and a biconcave negative lens L16, and has a positive refractive power as a whole. L15 is a joint surface.

  The fifth lens group G5 includes, in order from the object side, a biconvex positive lens L17. The fifth lens group G5 has a positive refractive power as a whole.

  When zooming from the wide-angle end to the telephoto end, the first lens group G1 moves to the object side. The second lens group G2 moves to the image side. The third lens group G3 moves to the object side. After the fourth lens group G4 has moved to the object side, the amount of movement becomes small and becomes almost fixed. The fifth lens group G5 is fixed. The aperture stop S moves together with the third lens group G3.

  The aspheric surfaces are the image side surface of the negative meniscus lens L9 on the image side of the second lens group G2, the object side surface of the biconvex positive lens L10 on the object side of the third lens group G3, and the negative meniscus lens on the image side. It is provided on six surfaces, that is, both surfaces of L13 and both surfaces of the biconvex positive lens L17 of the fifth lens group G5.

  Next, an image forming optical system according to Example 7 of the present invention will be described. 13A and 13B are cross-sectional views along the optical axis showing the optical configuration of the imaging optical system according to Example 7 of the present invention when focusing on an object point at infinity. FIG. 13A is a wide-angle end, and FIG. The distance state, (c) is a cross-sectional view at the telephoto end.

  14A and 14B are diagrams illustrating spherical aberration, astigmatism, distortion, and lateral chromatic aberration when the imaging optical system according to Example 7 is focused on an object point at infinity, where FIG. 14A is a wide-angle end, and FIG. Intermediate focal length state, (c) shows the state at the telephoto end.

  As shown in FIG. 13, the imaging optical system according to the seventh embodiment includes, in order from the object side, the first lens group G1, the second lens group G2, the aperture stop S, the third lens group G3, and the fourth lens group. It has a lens group G4 and a fifth lens group G5.

The first lens group G1 includes, in order from the object side, a negative meniscus lens L1 (optical element B) having a convex surface facing the object side, a positive meniscus lens L2 (refractive optical element A) having a convex surface facing the object side, and the object side. It consists of a cemented lens with a positive meniscus lens L3 (optical element C) with a convex surface and a positive meniscus lens L4 with a convex surface toward the object side, and has a positive refractive power as a whole. Here, the partial dispersion ratio (θgF _A ) of the refractive optical element A of the cemented lens of the first lens group G1 is 0.761. The Abbe number (νd _A ) of the refractive optical element A is 17.01.

  In order from the object side, the second lens group G2 includes a negative meniscus lens L5 having a convex surface directed toward the object side, a cemented lens of a biconcave negative lens L6 and a biconvex positive lens L8, and a negative lens having a convex surface directed toward the image side. And a meniscus lens L9, which has a negative refractive power as a whole. L7 is a joint surface.

  The third lens group G3 includes, in order from the object side, a biconvex positive lens L10, a negative meniscus lens L11 with a convex surface facing the object side, a biconvex positive lens L12, and a negative meniscus lens L13 with a convex surface facing the object side. And has a positive refractive power as a whole.

  The fourth lens group G4 includes, in order from the object side, a cemented lens of a biconvex positive lens L14 and a biconcave negative lens L16, and has a positive refractive power as a whole. L15 is a joint surface.

  The fifth lens group G5 includes, in order from the object side, a biconvex positive lens L17. The fifth lens group G5 has a positive refractive power as a whole.

  When zooming from the wide-angle end to the telephoto end, the first lens group G1 moves to the object side. The second lens group G2 moves to the image side. The third lens group G3 moves to the object side. After the fourth lens group G4 has moved to the object side, the amount of movement becomes small and becomes almost fixed. The fifth lens group is fixed. The aperture stop S moves together with the third lens group G3.

  The aspheric surfaces are the image side surface of the negative meniscus lens L9 on the image side of the second lens group G2, the object side surface of the biconvex positive lens L10 on the object side of the third lens group G3, and the negative meniscus lens on the image side. It is provided on six surfaces, that is, both surfaces of L13 and both surfaces of the biconvex positive lens L17 of the fifth lens group G5.

  Next, an image forming optical system according to Example 8 of the present invention will be described. 15A and 15B are cross-sectional views along the optical axis showing the optical configuration of the imaging optical system according to Example 8 of the present invention when focusing on an object point at infinity. FIG. 15A is a wide-angle end, and FIG. The distance state, (c) is a cross-sectional view at the telephoto end.

  16A and 16B are diagrams showing spherical aberration, astigmatism, distortion, and lateral chromatic aberration when the imaging optical system according to Example 8 is focused on an object point at infinity. FIG. 16A is a wide-angle end, and FIG. Intermediate focal length state, (c) shows the state at the telephoto end.

  As shown in FIG. 15, the imaging optical system according to the eighth embodiment includes, in order from the object side, the first lens group G1, the second lens group G2, the aperture stop S, the third lens group G3, and the fourth lens group. It has a lens group G4 and a fifth lens group G5.

The first lens group G1 includes, in order from the object side, a negative meniscus lens L1 (optical element B) having a convex surface facing the object side, a positive meniscus lens L2 (refractive optical element A) having a convex surface facing the object side, and a biconvex positive The lens is composed of a cemented lens with the lens L3 (optical element C) and a positive meniscus lens L4 having a convex surface facing the object side, and has a positive refractive power as a whole. Here, the partial dispersion ratio (θgF _A ) of the refractive optical element A of the cemented lens of the first lens group G1 is 0.761. The Abbe number (νd _A ) of the refractive optical element A is 17.01.

  In order from the object side, the second lens group G2 includes a negative meniscus lens L5 having a convex surface directed toward the object side, a cemented lens of a biconcave negative lens L6 and a biconvex positive lens L8, and a negative lens having a convex surface directed toward the image side. And a meniscus lens L9, which has a negative refractive power as a whole. L7 is a joint surface.

  The third lens group G3 includes, in order from the object side, a biconvex positive lens L10, a negative meniscus lens L11 with a convex surface facing the object side, a biconvex positive lens L12, and a negative meniscus lens L13 with a convex surface facing the object side. And has a positive refractive power as a whole.

  The fourth lens group G4 includes, in order from the object side, a cemented lens of a biconvex positive lens L14 and a biconcave negative lens L16, and has a positive refractive power as a whole. L15 is a joint surface.

  The fifth lens group G5 includes, in order from the object side, a biconvex positive lens L17. The fifth lens group G5 has a positive refractive power as a whole.

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

  The aspheric surfaces are the image side surface of the negative meniscus lens L9 on the image side of the second lens group G2, the object side surface of the biconvex positive lens L10 on the object side of the third lens group G3, and the negative meniscus lens on the image side. It is provided on six surfaces, that is, both surfaces of L13 and both surfaces of the biconvex positive lens L17 of the fifth lens group G5.

  Next, an image forming optical system according to Example 9 of the present invention will be described. FIGS. 17A and 17B are cross-sectional views along the optical axis showing the optical configuration of the imaging optical system according to Example 9 of the present invention when focusing on an object point at infinity. FIG. 17A is a wide-angle end, and FIG. The distance state, (c) is a cross-sectional view at the telephoto end.

  18A and 18B are diagrams showing spherical aberration, astigmatism, distortion aberration, and chromatic aberration of magnification when the imaging optical system according to Example 9 is focused on an object point at infinity. FIG. 18A is a wide-angle end, and FIG. Intermediate focal length state, (c) shows the state at the telephoto end.

  As shown in FIG. 17, the imaging optical system of Example 9 includes, in order from the object side, the first lens group G1, the second lens group G2, the aperture stop S, the third lens group G3, and the fourth lens group. It has a lens group G4 and a fifth lens group G5.

The first lens group G1 includes, in order from the object side, a negative meniscus lens L1 (optical element B) having a convex surface facing the object side, a positive meniscus lens L2 (refractive optical element A) having a convex surface facing the object side, and the object side. It consists of a cemented lens with a positive meniscus lens L3 (optical element C) with a convex surface and a positive meniscus lens L4 with a convex surface toward the object side, and has a positive refractive power as a whole. Here, the partial dispersion ratio (θgF _A ) of the refractive optical element A of the cemented lens of the first lens group G1 is 0.817. The Abbe number (νd _A ) of the refractive optical element A is 23.36.

  In order from the object side, the second lens group G2 includes a negative meniscus lens L5 having a convex surface directed toward the object side, a cemented lens of a biconcave negative lens L6 and a biconvex positive lens L8, and a negative lens having a convex surface directed toward the image side. And a meniscus lens L9, which has a negative refractive power as a whole. L7 is a joint surface.

  The third lens group G3 includes, in order from the object side, a biconvex positive lens L10, a negative meniscus lens L11 with a convex surface facing the object side, a biconvex positive lens L12, and a negative meniscus lens L13 with a convex surface facing the object side. And has a positive refractive power as a whole.

  The fourth lens group G4 includes, in order from the object side, a cemented lens of a biconvex positive lens L14 and a biconcave negative lens L16, and has a positive refractive power as a whole. L15 is a joint surface.

  The fifth lens group G5 includes, in order from the object side, a biconvex positive lens L17. The fifth lens group G5 has a positive refractive power as a whole.

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

  The aspheric surfaces are the image side surface of the negative meniscus lens L9 on the image side of the second lens group G2, the object side surface of the biconvex positive lens L10 on the object side of the third lens group G3, and the negative meniscus lens on the image side. It is provided on six surfaces, that is, both surfaces of L13 and both surfaces of the biconvex positive lens L17 of the fifth lens group G5.

  From the tenth to the sixteenth examples, in order from the object side, the first lens group G1 having a positive refractive power, the second lens group G2 having a negative refractive power, an aperture stop S, and a third lens having a positive refractive power. The lens unit includes a lens group G3, a fourth lens group G4 having a positive refractive power, and a fifth lens group G5 having a positive refractive power. The first lens group G1 has one positive lens, a negative lens (optical element B), the refractive optical element A having positive refractive power, and a positive lens having positive refractive power (optical element C). is doing. With the configuration of the refractive optical element A and the first lens group G1, chromatic aberration correction is effectively performed at the telephoto end.

  The second lens group G2 includes a negative lens, a negative lens, a positive lens, and a negative lens. A high zoom ratio is achieved by the configuration of the second lens group G2.

  The distance between the first lens group G1 and the second lens group G2 is larger at the telephoto end than at the wide-angle end, the distance between the second lens group G2 and the third lens group G3 is small, and the third lens group G3 and the fourth lens group G4. Zooming is performed by changing the interval between adjacent lens groups so that the interval between the lens groups G4 is increased.

  In addition, the fourth lens group G4 corrects the image plane variation due to zooming, and the distance between the fourth lens group G4 and the fifth lens group G5 satisfies the conditional expression (20).

  Next, an image forming optical system according to Example 10 of the present invention will be described. 19A and 19B are cross-sectional views along the optical axis showing the optical configuration of the imaging optical system according to Example 10 of the present invention when focusing on an object point at infinity. FIG. 19A is a wide-angle end, and FIG. The distance state, (c) is a cross-sectional view at the telephoto end.

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

  As shown in FIG. 19, the imaging optical system of Example 10 includes, in order from the object side, a first lens group G1, a second lens group G2, an aperture stop S, a third lens group G3, and a fourth lens group. It has a lens group G4 and a fifth lens group G5.

The first lens group G1 includes, in order from the object side, a positive meniscus lens L1 having a convex surface facing the object side, a negative meniscus lens L2 (optical element B) having a convex surface facing the object side, and a positive surface having a convex surface facing the object side. It is composed of a meniscus lens L3 (refractive optical element A) and a cemented lens of a positive meniscus lens L4 (optical element C) having a convex surface facing the object side, and has a positive refractive power as a whole. Here, the partial dispersion ratio (θgF _A ) of the refractive optical element A of the cemented lens of the first lens group G1 is 0.668. The Abbe number (νd _A ) of the refractive optical element A is 23.38.

  In order from the object side, the second lens group G2 includes a negative meniscus lens L5 having a convex surface directed toward the object side, a cemented lens of a biconcave negative lens L6 and a biconvex positive lens L8, and a negative lens having a convex surface directed toward the image side. And a meniscus lens L9, which has a negative refractive power as a whole. L7 is a joint surface.

  The third lens group G3 includes, in order from the object side, a biconvex positive lens L10, a negative meniscus lens L11 with a convex surface facing the object side, a biconvex positive lens L12, and a negative meniscus lens L13 with a convex surface facing the object side. And has a positive refractive power as a whole.

  The fourth lens group G4 includes, in order from the object side, a cemented lens of a biconvex positive lens L14 and a biconcave negative lens L16, and has a positive refractive power as a whole. L15 is a joint surface.

  The fifth lens group G5 includes, in order from the object side, a biconvex positive lens L17. The fifth lens group G5 has a positive refractive power as a whole.

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

  The aspheric surfaces are the image side surface of the negative meniscus lens L9 on the image side of the second lens group G2, the object side surface of the biconvex positive lens L10 on the object side of the third lens group G3, and the negative meniscus lens on the image side. It is provided on six surfaces, that is, both surfaces of L13 and both surfaces of the biconvex positive lens L17 of the fifth lens group G5.

  Next, an image forming optical system according to Example 11 of the present invention will be described. FIGS. 21A and 21B are cross-sectional views along the optical axis showing the optical configuration of the imaging optical system according to Example 11 of the present invention when focusing on an object point at infinity. FIG. 21A is a wide-angle end, and FIG. The distance state, (c) is a cross-sectional view at the telephoto end.

  FIG. 22 is a diagram showing spherical aberration, astigmatism, distortion, and lateral chromatic aberration when the imaging optical system according to Example 11 is focused on an object point at infinity, where (a) is the wide-angle end, and (b) is Intermediate focal length state, (c) shows the state at the telephoto end.

  In the imaging optical system of Example 11, as shown in FIG. 21, in order from the object side, the first lens group G1, the second lens group G2, the aperture stop S, the third lens group G3, and the fourth lens group. It has a lens group G4 and a fifth lens group G5.

The first lens group G1 includes, in order from the object side, a positive meniscus lens L1 having a convex surface facing the object side, a negative meniscus lens L2 (optical element B) having a convex surface facing the object side, and a positive surface having a convex surface facing the object side. It is composed of a meniscus lens L3 (refractive optical element A) and a cemented lens of a positive meniscus lens L4 (optical element C) having a convex surface facing the object side, and has a positive refractive power as a whole. Here, the partial dispersion ratio (θgF _A ) of the refractive optical element A of the cemented lens of the first lens group G1 is 0.668. The Abbe number (νd _A ) of the refractive optical element A is 23.38.

  In order from the object side, the second lens group G2 includes a negative meniscus lens L5 having a convex surface directed toward the object side, a cemented lens of a biconcave negative lens L6 and a biconvex positive lens L8, and a negative lens having a convex surface directed toward the image side. And a meniscus lens L9, which has a negative refractive power as a whole. L7 is a joint surface.

  The third lens group G3 includes, in order from the object side, a biconvex positive lens L10, a negative meniscus lens L11 with a convex surface facing the object side, a biconvex positive lens L12, and a negative meniscus lens L13 with a convex surface facing the object side. And has a positive refractive power as a whole.

  The fourth lens group G4 includes, in order from the object side, a cemented lens of a biconvex positive lens L14 and a biconcave negative lens L16, and has a positive refractive power as a whole. L15 is a joint surface.

  The fifth lens group G5 includes, in order from the object side, a biconvex positive lens L17. The fifth lens group G5 has a positive refractive power as a whole.

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

  The aspheric surfaces are the image side surface of the negative meniscus lens L9 on the image side of the second lens group G2, the object side surface of the biconvex positive lens L10 on the object side of the third lens group G3, and the negative meniscus lens on the image side. It is provided on six surfaces, that is, both surfaces of L13 and both surfaces of the biconvex positive lens L17 of the fifth lens group G5.

  Next, an image forming optical system according to Example 12 of the present invention will be described. 23A and 23B are cross-sectional views along the optical axis showing the optical configuration of the imaging optical system according to Example 12 of the present invention when focusing on an object point at infinity. FIG. 23A is a wide-angle end, and FIG. Distance state, (c) is a cross-sectional view at the telephoto end.

  24A and 24B are diagrams showing spherical aberration, astigmatism, distortion, and lateral chromatic aberration when the imaging optical system according to Example 12 is focused on an object point at infinity. FIG. 24A is a wide-angle end, and FIG. Intermediate focal length state, (c) shows the state at the telephoto end.

  As shown in FIG. 23, the image forming optical system according to the twelfth embodiment includes, in order from the object side, the first lens group G1, the second lens group G2, the aperture stop S, the third lens group G3, and the fourth lens group. It has a lens group G4 and a fifth lens group G5.

The first lens group G1 includes, in order from the object side, a positive meniscus lens L1 having a convex surface facing the object side, a negative meniscus lens L2 (optical element B) having a convex surface facing the object side, and a positive surface having a convex surface facing the object side. It is composed of a meniscus lens L3 (refractive optical element A) and a cemented lens of a positive meniscus lens L4 (optical element C) having a convex surface facing the object side, and has a positive refractive power as a whole. Here, the partial dispersion ratio (θgF _A ) of the refractive optical element A of the cemented lens of the first lens group G1 is 0.690. The Abbe number (νd _A ) of the refractive optical element A is 20.00.

  In order from the object side, the second lens group G2 includes a negative meniscus lens L5 having a convex surface directed toward the object side, a cemented lens of a biconcave negative lens L6 and a biconvex positive lens L8, and a negative lens having a convex surface directed toward the image side. And a meniscus lens L9, which has a negative refractive power as a whole. L7 is a joint surface.

  The third lens group G3 includes, in order from the object side, a biconvex positive lens L10, a negative meniscus lens L11 with a convex surface facing the object side, a biconvex positive lens L12, and a negative meniscus lens L13 with a convex surface facing the object side. And has a positive refractive power as a whole.

  The fourth lens group G4 includes, in order from the object side, a cemented lens of a biconvex positive lens L14 and a biconcave negative lens L16, and has a positive refractive power as a whole. L15 is a joint surface.

  The fifth lens group G5 includes, in order from the object side, a biconvex positive lens L17. The fifth lens group G5 has a positive refractive power as a whole.

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

  The aspheric surfaces are the image side surface of the negative meniscus lens L9 on the image side of the second lens group G2, the object side surface of the biconvex positive lens L10 on the object side of the third lens group G3, and the negative meniscus lens on the image side. It is provided on six surfaces, that is, both surfaces of L13 and both surfaces of the biconvex positive lens L17 of the fifth lens group G5.

  Next, an image forming optical system according to Example 13 of the present invention will be described. 25A and 25B are cross-sectional views along the optical axis showing the optical configuration of the imaging optical system according to Example 13 of the present invention when focusing on an object point at infinity. FIG. 25A is a wide-angle end, and FIG. The distance state, (c) is a cross-sectional view at the telephoto end.

  FIG. 26 is a diagram showing spherical aberration, astigmatism, distortion aberration, and chromatic aberration of magnification when the imaging optical system according to Example 13 is focused on an object point at infinity, where (a) is the wide-angle end, and (b) is Intermediate focal length state, (c) shows the state at the telephoto end.

  As shown in FIG. 25, the imaging optical system of Example 13 includes, in order from the object side, the first lens group G1, the second lens group G2, the aperture stop S, the third lens group G3, and the fourth lens group. It has a lens group G4 and a fifth lens group G5.

The first lens group G1 includes, in order from the object side, a positive meniscus lens L1 having a convex surface facing the object side, a negative meniscus lens L2 (optical element B) having a convex surface facing the object side, and a positive surface having a convex surface facing the object side. It is composed of a meniscus lens L3 (refractive optical element A) and a cemented lens of a positive meniscus lens L4 (optical element C) having a convex surface facing the object side, and has a positive refractive power as a whole. Here, the partial dispersion ratio (θgF _A ) of the refractive optical element A of the cemented lens of the first lens group G1 is 0.738. The Abbe number (νd _A ) of the refractive optical element A is 15.00.

  In order from the object side, the second lens group G2 includes a negative meniscus lens L5 having a convex surface directed toward the object side, a cemented lens of a biconcave negative lens L6 and a biconvex positive lens L8, and a negative lens having a convex surface directed toward the image side. And a meniscus lens L9, which has a negative refractive power as a whole. L7 is a joint surface.

  The third lens group G3 includes, in order from the object side, a biconvex positive lens L10, a negative meniscus lens L11 with a convex surface facing the object side, a biconvex positive lens L12, and a negative meniscus lens L13 with a convex surface facing the object side. And has a positive refractive power as a whole.

  The fourth lens group G4 includes, in order from the object side, a cemented lens of a biconvex positive lens L14 and a biconcave negative lens L16, and has a positive refractive power as a whole. L15 is a joint surface.

  The fifth lens group G5 includes, in order from the object side, a biconvex positive lens L17. The fifth lens group G5 has a positive refractive power as a whole.

  When zooming from the wide-angle end to the telephoto end, the first lens group G1 moves to the object side. After the second lens group G2 has moved to the image side, the amount of movement becomes small and is almost fixed. The third lens group G3 moves to the object side. The fourth lens group G4 moves to the image side after moving to the object side. The fifth lens group G5 is fixed. The aperture stop S moves together with the third lens group G3.

  The aspheric surfaces are the image side surface of the negative meniscus lens L9 on the image side of the second lens group G2, the object side surface of the biconvex positive lens L10 on the object side of the third lens group G3, and the negative meniscus lens on the image side. It is provided on six surfaces, that is, both surfaces of L13 and both surfaces of the biconvex positive lens L17 of the fifth lens group G5.

  Next, an image forming optical system according to Example 14 of the present invention will be described. 27A and 27B are cross-sectional views along the optical axis showing the optical configuration of the imaging optical system according to Example 14 of the present invention when focusing on an object point at infinity. FIG. 27A is a wide-angle end, and FIG. Distance state, (c) is a cross-sectional view at the telephoto end.

  28A and 28B are diagrams showing spherical aberration, astigmatism, distortion, and lateral chromatic aberration when the imaging optical system according to Example 14 is focused on an object point at infinity. FIG. 28A shows a wide-angle end, and FIG. Intermediate focal length state, (c) shows the state at the telephoto end.

  In the imaging optical system of Example 14, as shown in FIG. 27, in order from the object side, the first lens group G1, the second lens group G2, the aperture stop S, the third lens group G3, and the fourth lens group. It has a lens group G4 and a fifth lens group G5.

The first lens group G1 includes, in order from the object side, a positive meniscus lens L1 having a convex surface facing the object side, a negative meniscus lens L2 (optical element B) having a convex surface facing the object side, and a positive surface having a convex surface facing the object side. It is composed of a meniscus lens L3 (refractive optical element A) and a cemented lens of a positive meniscus lens L4 (optical element C) having a convex surface facing the object side, and has a positive refractive power as a whole. Here, the partial dispersion ratio (θgF _A ) of the refractive optical element A of the cemented lens of the first lens group G1 is 0.761. The Abbe number (νd _A ) of the refractive optical element A is 17.01.

  In order from the object side, the second lens group G2 includes a negative meniscus lens L5 having a convex surface directed toward the object side, a cemented lens of a biconcave negative lens L6 and a biconvex positive lens L8, and a negative lens having a convex surface directed toward the image side. And a meniscus lens L9, which has a negative refractive power as a whole. L7 is a joint surface.

  The third lens group G3 includes, in order from the object side, a biconvex positive lens L10, a negative meniscus lens L11 with a convex surface facing the object side, a biconvex positive lens L12, and a negative meniscus lens L13 with a convex surface facing the object side. And has a positive refractive power as a whole.

  The fourth lens group G4 includes, in order from the object side, a cemented lens of a biconvex positive lens L14 and a biconcave negative lens L16, and has a positive refractive power as a whole. L15 is a joint surface.

  The fifth lens group G5 includes, in order from the object side, a biconvex positive lens L17. The fifth lens group G5 has a positive refractive power as a whole.

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

  The aspheric surfaces are the image side surface of the negative meniscus lens L9 on the image side of the second lens group G2, the object side surface of the biconvex positive lens L10 on the object side of the third lens group G3, and the negative meniscus lens on the image side. It is provided on six surfaces, that is, both surfaces of L13 and both surfaces of the biconvex positive lens L17 of the fifth lens group G5.

  Next, an image forming optical system according to Example 15 of the present invention will be described. 29A and 29B are cross-sectional views along the optical axis showing the optical configuration of the imaging optical system according to Example 15 of the present invention when focusing on an object point at infinity. FIG. 29A is a wide angle end, and FIG. 29B is an intermediate focus. Distance state, (c) is a cross-sectional view at the telephoto end.

  FIG. 30 is a diagram illustrating spherical aberration, astigmatism, distortion aberration, and chromatic aberration of magnification when the imaging optical system according to Example 15 is focused on an object point at infinity, where (a) is a wide-angle end, and (b) is a diagram illustrating Intermediate focal length state, (c) shows the state at the telephoto end.

  As shown in FIG. 29, the imaging optical system of Example 15 includes, in order from the object side, the first lens group G1, the second lens group G2, the aperture stop S, the third lens group G3, and the fourth lens group. It has a lens group G4 and a fifth lens group G5.

The first lens group G1 includes, in order from the object side, a positive meniscus lens L1 having a convex surface facing the object side, a negative meniscus lens L2 (optical element B) having a convex surface facing the object side, and a positive surface having a convex surface facing the object side. It is composed of a meniscus lens L3 (refractive optical element A) and a cemented lens of a positive meniscus lens L4 (optical element C) having a convex surface facing the object side, and has a positive refractive power as a whole. Here, the partial dispersion ratio (θgF _A ) of the refractive optical element A of the cemented lens of the first lens group G1 is 0.817. The Abbe number (νd _A ) of the refractive optical element A is 16.99.

  In order from the object side, the second lens group G2 includes a negative meniscus lens L5 having a convex surface directed toward the object side, a cemented lens of a biconcave negative lens L6 and a biconvex positive lens L8, and a negative lens having a convex surface directed toward the image side. And a meniscus lens L9, which has a negative refractive power as a whole. L7 is a joint surface.

  The third lens group G3 includes, in order from the object side, a biconvex positive lens L10, a negative meniscus lens L11 with a convex surface facing the object side, a biconvex positive lens L12, and a negative meniscus lens L13 with a convex surface facing the object side. And has a positive refractive power as a whole.

  The fourth lens group G4 includes, in order from the object side, a cemented lens of a biconvex positive lens L14 and a biconcave negative lens L16, and has a positive refractive power as a whole. L15 is a joint surface.

  The fifth lens group G5 includes, in order from the object side, a biconvex positive lens L17. The fifth lens group G5 has a positive refractive power as a whole.

  When zooming from the wide-angle end to the telephoto end, the first lens group G1 moves to the object side. After the second lens group G2 moves to the image side, the amount of movement becomes small and becomes almost fixed. The third lens group G3 moves to the object side. The fourth lens group G4 moves to the image side after moving to the object side. The fifth lens group G5 is fixed. The aperture stop S moves together with the third lens group G3.

  The aspheric surfaces are the image side surface of the negative meniscus lens L9 on the image side of the second lens group G2, the object side surface of the biconvex positive lens L10 on the object side of the third lens group G3, and the negative meniscus lens on the image side. It is provided on six surfaces, that is, both surfaces of L13 and both surfaces of the biconvex positive lens L17 of the fifth lens group G5.

  Next, an image forming optical system according to Example 16 of the present invention will be described. FIGS. 31A and 31B are cross-sectional views along the optical axis showing the optical configuration of the imaging optical system according to Example 16 of the present invention when focusing on an object point at infinity. FIG. 31A is a wide-angle end, and FIG. The distance state, (c) is a cross-sectional view at the telephoto end.

  32A and 32B are diagrams showing spherical aberration, astigmatism, distortion, and lateral chromatic aberration when the imaging optical system according to Example 16 is focused on an object point at infinity. FIG. 32A is a wide-angle end, and FIG. Intermediate focal length state, (c) shows the state at the telephoto end.

  In the imaging optical system of Example 16, as shown in FIG. 31, in order from the object side, the first lens group G1, the second lens group G2, the aperture stop S, the third lens group G3, and the fourth lens group are arranged. It has a lens group G4 and a fifth lens group G5.

The first lens group G1 includes, in order from the object side, a positive meniscus lens L1 having a convex surface facing the object side, a negative meniscus lens L2 (optical element B) having a convex surface facing the object side, and a positive surface having a convex surface facing the object side. It is composed of a meniscus lens L3 (refractive optical element A) and a cemented lens of a positive meniscus lens L4 (optical element C) having a convex surface facing the object side, and has a positive refractive power as a whole. Here, the partial dispersion ratio (θgF _A ) of the refractive optical element A of the cemented lens of the first lens group G1 is 0.817. The Abbe number (νd _A ) of the refractive optical element A is 23.36.

  In order from the object side, the second lens group G2 includes a negative meniscus lens L5 having a convex surface directed toward the object side, a cemented lens of a biconcave negative lens L6 and a biconvex positive lens L8, and a negative lens having a convex surface directed toward the image side. And a meniscus lens L9, which has a negative refractive power as a whole. L7 is a joint surface.

  The third lens group G3 includes, in order from the object side, a biconvex positive lens L10, a negative meniscus lens L11 with a convex surface facing the object side, a biconvex positive lens L12, and a negative meniscus lens L13 with a convex surface facing the object side. And has a positive refractive power as a whole.

  The fourth lens group G4 includes, in order from the object side, a cemented lens of a biconvex positive lens L14 and a biconcave negative lens L16, and has a positive refractive power as a whole. L15 is a joint surface.

  The fifth lens group G5 includes, in order from the object side, a biconvex positive lens L17. The fifth lens group G5 has a positive refractive power as a whole.

  When zooming from the wide-angle end to the telephoto end, the first lens group G1 moves to the object side. After the second lens group G2 moves to the image side, the amount of movement becomes small and becomes almost fixed. The third lens group G3 moves to the object side. The fourth lens group G4 moves to the image side after moving to the object side. The fifth lens group G5 is fixed. The aperture stop S moves together with the third lens group G3.

  The aspheric surfaces are the image side surface of the negative meniscus lens L9 on the image side of the second lens group G2, the object side surface of the biconvex positive lens L10 on the object side of the third lens group G3, and the negative meniscus lens on the image side. It is provided on six surfaces, that is, both surfaces of L13 and both surfaces of the biconvex positive lens L17 of the fifth lens group G5.

  Next, numerical data of optical members constituting the imaging optical system of each of the above embodiments will be listed. In the numerical data of each embodiment, r1, r2,... Are the radius of curvature of each lens surface, d1, d2,... Are the thickness or air spacing of each lens, and nd1, nd2,. Are the Abbe number of each lens, Fno. Is the F number, f is the focal length of the entire system, and D0 is the distance from the object to the first surface. Further, asp indicates an aspheric surface, and STO indicates an aperture.

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

  In the following numerical examples, the exit pupil position A indicates the exit pupil position from the last lens surface, and the exit pupil position B indicates the exit pupil position from the image plane.

Numerical example 1
Unit mm

Surface data surface number rd nd νd ER
Object ∞ ∞
1 57.000 1.00 1.80810 22.76 17.50
2 31.922 1.00 1.63387 23.38 16.05
3 39.229 4.40 1.49700 81.54 16.00
4 1466.041 0.10 15.50
5 36.008 3.76 1.65160 58.55 14.42
6 121.871 Variable 14.00
7 73.573 1.10 1.88300 40.76 9.19
8 7.653 4.79 6.47
9 -46.254 0.80 1.88300 40.76 6.37
10 12.396 0.01 1.51400 42.83 6.35
11 12.396 4.87 1.78472 25.68 6.36
12 -12.684 1.15 6.40
13 -11.499 0.80 1.77250 49.60 5.63
14 ^* -175.425 Variable 5.66
15 (Aperture) ∞ 1.30 3.94
16 ^* 10.743 4.93 1.58913 61.14 4.60
17 -78.051 0.10 4.61
18 28.041 2.77 1.84666 23.78 4.59
19 10.632 1.42 4.29
20 14.230 3.12 1.49700 81.54 4.56
21 -36.985 0.64 4.60
22 ^* 69.435 1.36 1.53071 55.69 4.58
23 ^* 34.607 Variable 4.58
24 19.130 2.68 1.49700 81.54 4.85
25 -119.090 0.01 1.51400 42.83 4.72
26 -119.090 0.82 1.80400 46.57 4.72
27 76.031 Variable 4.67
28 ^* 147.374 1.63 1.53071 55.69 4.16
29 ^* -67.939 1.09 4.07
30 ∞ 4.00 1.51680 64.20 4.01
31 ∞ 1.05 3.85
Image plane ∞

Aspheric data 14th surface
K = 0.000
A2 = 0.0000E + 00, A4 = -9.19823e-05, A6 = -8.80923e-07, A8 = 4.39702e-08, A10 = -1.24247e-09
16th page
K = 0.000
A2 = 0.0000E + 00, A4 = -8.77784e-05, A6 = -1.01116e-06, A8 = 5.64180e-08, A10 = -2.23368e-09,
A12 = 3.59187e-11
22nd page
K = 0.000
A2 = 0.0000E + 00, A4 = -2.17277e-04, A6 = 5.36299e-06, A8 = -5.28517e-07, A10 = 1.10330e-08,
A12 = -1.37250e-10
23rd page
K = 0.000
A2 = 0.0000E + 00, A4 = -1.09771e-04, A6 = 5.91402e-06, A8 = -5.09130e-07, A10 = 8.38419e-09,
A12 = -4.36735e-11
28th page
K = 0.000
A2 = 0.0000E + 00, A4 = 8.15873e-04, A6 = 4.82675e-06, A8 = -2.20386e-06, A10 = 4.10510e-08
29th page
K = 0.000
A2 = 0.0000E + 00, A4 = 1.26016e-03, A6 = 1.60282e-05, A8 = -3.90922e-06, A10 = 7.56282e-08

Various data zoom ratio 17.94
Wide angle Medium Telephoto focal length 4.68 19.73 83.85
FNO. 2.66 4.04 4.20
Angle of view 2ω 78.04 20.13 4.80
Image height 3.6 3.6 3.6
Total lens length 83.15 99.31 113.64
BF 4.78 4.68 4.78

d6 1.00 18.10 36.91
d14 25.86 8.76 2.30
d23 1.28 9.91 9.55
d27 5.68 13.31 15.55

Entrance pupil position 19.02 62.76 288.40
Exit pupil position A -31.23 -88.71 -95.31
Exit pupil position B -36.01 -93.39 -100.10
Front principal point 23.09 78.33 302.00
Rear principal point position -3.62 -18.78 -82.80

Single lens data lens Start surface Focal length
L1 1 -91.42
L2 2 256.77
L3 3 81.02
L4 5 77.10
L5 7 -9.75
L6 9 -11.00
L7 10 8.81E + 04
L8 11 8.73
L9 13 -15.96
L10 16 16.37
L11 18 -21.82
L12 20 21.10
L13 22 -131.79
L14 24 33.38
L15 25 8.13E + 06
L16 26 -57.61
L17 28 87.85

Zoom lens group data group Start surface Focal length Lens configuration length Front principal point position Rear principal point position
1 1 56.6886 10.2644 1.9306 -4.5773
2 7 -6.8387 13.5160 1.8939 -7.0311
3 15 17.3424 15.6380 1.5104 -9.6395
4 24 73.7783 3.5080 -2.0985 -4.2304
5 28 87.8520 6.7160 0.7294 -4.0624
Group Start surface Wide angle magnification Medium magnification Telephoto magnification
1 1 0.0000 0.0000 0.0000
2 7 -0.1614 -0.2705 -1.0566
3 15 -0.6938 -2.0059 -2.2929
4 24 0.7821 0.6803 0.6483
5 28 0.9418 0.9429 0.9418

Numerical example 2
Unit mm

Surface data surface number rd nd νd ER
Object ∞ ∞
1 62.000 1.00 1.79925 24.62 17.10
2 32.285 0.97 1.63387 23.38 15.66
3 37.493 4.42 1.49700 81.54 15.51
4 5089.283 0.10 15.50
5 35.495 3.22 1.65160 58.55 14.25
6 139.627 Variable 14.00
7 72.020 1.10 1.88300 40.76 9.21
8 7.692 4.79 6.51
9 -46.254 0.80 1.88300 40.76 6.41
10 12.396 0.01 1.51400 42.83 6.42
11 12.396 4.87 1.78472 25.68 6.42
12 -12.684 1.15 6.47
13 -11.499 0.80 1.77250 49.60 5.73
14 ^* -100.567 Variable 5.78
15 (Aperture) ∞ 1.30 3.94
16 ^* 10.743 4.93 1.58913 61.14 4.59
17 -78.051 0.10 4.59
18 28.041 2.77 1.84666 23.78 4.57
19 10.504 1.42 4.26
20 13.924 3.12 1.49700 81.54 4.53
21 -36.985 0.64 4.57
22 ^* 73.125 1.36 1.53071 55.69 4.54
23 ^* 35.555 Variable 4.55
24 19.130 2.68 1.49700 81.54 4.84
25 -119.090 0.01 1.51400 42.83 4.71
26 -119.090 0.82 1.80400 46.57 4.71
27 76.031 Variable 4.66
28 ^* 147.374 1.63 1.53071 55.69 4.17
29 ^* -67.939 1.09 4.09
30 ∞ 4.00 1.51680 64.20 4.02
31 ∞ 1.05 3.86
Image plane ∞

Aspheric data 14th surface
K = 0.000
A2 = 0.0000E + 00, A4 = -9.19823e-05, A6 = -8.80923e-07, A8 = 4.39702e-08, A10 = -1.24247e-09
16th page
K = 0.000
A2 = 0.0000E + 00, A4 = -8.77784e-05, A6 = -1.01116e-06, A8 = 5.64180e-08, A10 = -2.23368e-09,
A12 = 3.59187e-11
22nd page
K = 0.000
A2 = 0.0000E + 00, A4 = -2.17277e-04, A6 = 5.36299e-06, A8 = -5.28517e-07, A10 = 1.10330e-08,
A12 = -1.37250e-10
23rd page
K = 0.000
A2 = 0.0000E + 00, A4 = -1.09771e-04, A6 = 5.91402e-06, A8 = -5.09130e-07, A10 = 8.38419e-09,
A12 = -4.36735e-11
28th page
K = 0.000
A2 = 0.0000E + 00, A4 = 8.15873e-04, A6 = 4.82675e-06, A8 = -2.20386e-06, A10 = 4.10510e-08
29th page
K = 0.000
A2 = 0.0000E + 00, A4 = 1.26016e-03, A6 = 1.60282e-05, A8 = -3.90922e-06, A10 = 7.56282e-08

Various data zoom ratio 17.94
Wide angle Medium Telephoto focal length 4.67 19.66 83.74
FNO. 2.63 4.04 4.18
Angle of view 2ω 78.21 20.19 4.79
Image height 3.6 3.6 3.6
Total lens length 82.81 97.59 113.67
BF 4.78 4.67 4.78

d6 1.00 17.41 37.50
d14 26.37 8.20 2.30
d23 1.29 10.69 15.74
d27 5.38 12.61 9.35

Entrance pupil position 18.42 57.36 285.45
Exit pupil position A -30.74 -91.92 -127.85
Exit pupil position B -35.52 -96.60 -132.63
Front principal point position 22.48 73.02 316.32
Rear principal point position -3.62 -18.71 -82.69

Single lens data lens Start surface Focal length
L1 1 -85.56
L2 2 341.89
L3 3 75.98
L4 5 72.16
L5 7 -9.83
L6 9 -11.00
L7 10 8.81E + 04
L8 11 8.73
L9 13 -16.87
L10 16 16.37
L11 18 -21.39
L12 20 20.78
L13 22 -132.06
L14 24 33.38
L15 25 8.13E + 06
L16 26 -57.61
L17 28 87.85

Zoom lens group data group Start surface Focal length Lens configuration length Front principal point position Rear principal point position
1 1 56.6370 9.7109 2.3763 -3.8229
2 7 -7.2149 13.5160 1.7381 -7.3581
3 15 17.3869 15.6380 1.5315 -9.6365
4 24 73.7783 3.5080 -2.0985 -4.2304
5 28 87.8520 6.7160 0.7294 -4.0624
Group Start surface Wide angle magnification Medium magnification Telephoto magnification
1 1 0.0000 0.0000 0.0000
2 7 -0.1683 -0.2728 -1.1349
3 15 -0.6611 -1.9566 -1.8888
4 24 0.7863 0.6898 0.7324
5 28 0.9418 0.9430 0.9418

Numerical example 3
Unit mm

Surface data surface number rd nd νd ER
Object ∞ ∞
1 63.000 1.80 1.84666 23.78 17.50
2 32.204 1.20 1.63387 23.38 15.68
3 40.265 4.14 1.49700 81.54 15.55
4 27463.875 0.10 15.50
5 37.567 3.28 1.65160 58.55 14.24
6 200.415 Variable 14.00
7 74.158 1.10 1.88300 40.76 9.19
8 7.718 4.79 6.50
9 -46.254 0.80 1.88300 40.76 6.40
10 12.396 0.01 1.51400 42.83 6.39
11 12.396 4.87 1.78472 25.68 6.39
12 -12.684 1.15 6.43
13 -11.499 0.80 1.77250 49.60 5.67
14 ^* -109.547 Variable 5.70
15 (Aperture) ∞ 1.30 3.71
16 ^* 10.743 4.93 1.58913 61.14 4.30
17 -78.051 0.10 4.32
18 28.041 2.77 1.84666 23.78 4.31
19 10.557 1.42 4.04
20 14.095 3.12 1.49700 81.54 4.31
21 -36.985 0.64 4.37
22 ^* 55.696 1.36 1.53071 55.69 4.34
23 ^* 41.000 Variable 4.33
24 19.130 2.68 1.49700 81.54 4.57
25 -119.090 0.01 1.51400 42.83 4.43
26 -119.090 0.82 1.80400 46.57 4.43
27 76.031 Variable 4.37
28 ^* 10184.593 1.63 1.53071 55.69 4.00
29 ^* -6651.678 1.09 3.90
30 ∞ 4.00 1.51680 64.20 3.88
31 ∞ 0.97 3.82
Image plane ∞

Aspheric data 14th surface
K = 0.000
A2 = 0.0000E + 00, A4 = -9.19823e-05, A6 = -8.80923e-07, A8 = 6.14733e-08, A10 = -1.47363e-09
16th page
K = 0.000
A2 = 0.0000E + 00, A4 = -8.77784e-05, A6 = -1.01116e-06, A8 = 5.64180e-08, A10 = -2.23368e-09,
A12 = 3.59187e-11
22nd page
K = 0.000
A2 = 0.0000E + 00, A4 = -2.17277e-04, A6 = 5.36299e-06, A8 = -5.28517e-07, A10 = 1.10330e-08,
A12 = -1.37250e-10
23rd page
K = 0.000
A2 = 0.0000E + 00, A4 = -1.09771e-04, A6 = 5.91402e-06, A8 = -5.09130e-07, A10 = 8.38419e-09,
A12 = -4.36735e-11
28th page
K = 0.000
A2 = 0.0000E + 00, A4 = 8.15873e-04, A6 = 4.82675e-06, A8 = -2.20386e-06, A10 = 4.10510e-08
29th page
K = 0.000
A2 = 0.0000E + 00, A4 = 1.26016e-03, A6 = 1.60282e-05, A8 = -3.90922e-06, A10 = 7.56282e-08

Various data zoom ratio 17.67
Wide angle Medium Telephoto focal length 4.69 18.54 82.94
FNO. 2.80 4.35 4.48
Angle of view 2ω 77.51 21.36 4.83
Image height 3.6 3.6 3.6
Total lens length 82.66 96.73 113.93
BF 4.70 4.68 4.77

d6 1.00 15.92 37.92
d14 25.89 8.47 2.30
d23 1.33 16.32 18.37
d27 4.95 6.53 5.77

Entrance pupil position 18.85 52.10 283.92
Exit pupil position A -23.33 -52.47 -56.89
Exit pupil position B -28.02 -57.15 -61.66
Front principal point position 22.76 64.62 255.30
Rear principal point position -3.72 -17.58 -81.89

Single lens data lens Start surface Focal length
L1 1 -79.96
L2 2 239.90
L3 3 81.13
L4 5 70.39
L5 7 -9.83
L6 9 -11.00
L7 10 8.81E + 04
L8 11 8.73
L9 13 -16.69
L10 16 16.37
L11 18 -21.56
L12 20 20.96
L13 22 -302.49
L14 24 33.38
L15 25 8.13E + 06
L16 26 -57.61
L17 28 7582.04

Zoom lens group data group Start surface Focal length Lens configuration length Front principal point position Rear principal point position
1 1 57.5126 10.5191 2.6843 -3.9664
2 7 -7.1497 13.5160 1.7695 -7.2924
3 15 16.7976 15.6380 2.1778 -9.3324
4 24 73.7783 3.5080 -2.0985 -4.2304
5 28 7582.0431 6.7160 0.6430 -4.1461
Group Start surface Wide angle magnification Medium magnification Telephoto magnification
1 1 0.0000 0.0000 0.0000
2 7 -0.1639 -0.2491 -1.0654
3 15 -0.6249 -1.6678 -1.7247
4 24 0.7975 0.7764 0.7854
5 28 0.9993 0.9993 0.9993

Numerical example 4
Unit mm

Surface data surface number rd nd νd ER
Object ∞ ∞
1 62.850 1.80 1.84666 23.78 17.50
2 32.458 0.96 1.63387 23.38 15.81
3 39.959 4.46 1.49700 81.54 15.76
4 64797.253 0.10 15.50
5 36.389 3.26 1.65160 58.55 14.24
6 168.319 Variable 14.00
7 79.899 1.10 1.88300 40.76 9.21
8 8.096 4.79 6.60
9 -46.254 0.80 1.88300 40.76 6.42
10 12.396 0.01 1.51400 42.83 6.32
11 12.396 4.87 1.78472 25.68 6.32
12 -12.684 1.15 6.32
13 -11.367 0.80 1.77250 49.60 5.34
14 ^* -74.335 Variable 5.30
15 (Aperture) ∞ 1.30 3.71
16 ^* 10.473 4.93 1.58913 61.14 4.30
17 -77.941 0.10 4.30
18 28.041 2.77 1.84666 23.78 4.29
19 10.091 1.42 4.00
20 13.652 3.12 1.49700 81.54 4.28
21 -36.985 0.64 4.34
22 ^* 42.769 1.36 1.53071 55.69 4.32
23 ^* 30.853 Variable 4.27
24 19.130 2.68 1.49700 81.54 4.50
25 -119.090 0.01 1.51400 42.83 4.37
26 -119.090 0.82 1.80400 46.57 4.37
27 76.031 Variable 4.32
28 ^* 49643.204 1.63 1.53071 55.69 3.97
29 ^* -13944.453 1.09 3.88
30 ∞ 4.00 1.51680 64.20 3.86
31 ∞ 0.98 3.81
Image plane ∞

Aspheric data 14th surface
K = 0.000
A2 = 0.0000E + 00, A4 = -9.19823e-05, A6 = 9.42847e-07, A8 = -3.71864e-08, A10 = 9.09734e-11
16th page
K = 0.000
A2 = 0.0000E + 00, A4 = -8.77784e-05, A6 = -1.52073e-06, A8 = 1.18883e-07, A10 = -6.93748e-09,
A12 = 1.46452e-10
22nd page
K = 0.000
A2 = 0.0000E + 00, A4 = -3.13848e-04, A6 = 8.15347e-06, A8 = -8.59408e-08, A10 = -1.12593e-08,
A12 = 5.16580e-10
23rd page
K = 0.000
A2 = 0.0000E + 00, A4 = -2.06308e-04, A6 = 8.95087e-06, A8 = -7.33310e-08, A10 = -1.52174e-08,
A12 = 7.32559e-10
28th page
K = 0.000
A2 = 0.0000E + 00, A4 = 8.15873e-04, A6 = 4.82675e-06, A8 = -3.85528e-06, A10 = 1.27474e-07
29th page
K = 0.000
A2 = 0.0000E + 00, A4 = 1.26016e-03, A6 = 1.60282e-05, A8 = -5.99523e-06, A10 = 1.80459e-07

Various data zoom ratio 17.43
Wide angle Medium Telephoto focal length 4.78 19.52 83.30
FNO. 2.79 3.95 4.02
Angle of view 2ω 76.54 20.31 4.82
Image height 3.6 3.6 3.6
Total lens length 84.07 96.08 108.53
BF 4.70 4.69 4.77

d6 1.00 19.57 38.43
d14 27.80 9.25 2.30
d23 0.83 8.81 13.76
d27 4.87 8.89 4.41

Entrance pupil position 19.51 67.92 312.80
Exit pupil position A -22.11 -38.51 -43.63
Exit pupil position B -26.81 -43.20 -48.39
Front principal point position 23.43 78.62 252.71
Rear principal point position -3.80 -18.56 -82.26

Single lens data lens Start surface Focal length
L1 1 -81.49
L2 2 259.86
L3 3 80.45
L4 5 70.56
L5 7 -10.28
L6 9 -11.00
L7 10 8.81E + 04
L8 11 8.73
L9 13 -17.47
L10 16 16.00
L11 18 -20.03
L12 20 20.48
L13 22 -217.26
L14 24 33.38
L15 25 8.13E + 06
L16 26 -57.61
L17 28 2.05E + 04

Zoom lens group data group Start surface Focal length Lens configuration length Front principal point position Rear principal point position
1 1 57.3912 10.5821 2.6900 -4.0128
2 7 -7.7120 13.5160 1.6628 -7.5497
3 15 16.9982 15.6380 1.7886 -9.5387
4 24 73.7783 3.5080 -2.0985 -4.2304
5 28 2.05E + 04 6.7160 0.8298 -3.9592

Group Start surface Wide angle magnification Medium magnification Telephoto magnification
1 1 0.0000 0.0000 0.0000
2 7 -0.1793 -0.3156 -1.3830
3 15 -0.5815 -1.4483 -1.3058
4 24 0.7985 0.7442 0.8039
5 28 0.9998 0.9998 0.9998

Numerical example 5
Unit mm

Surface data surface number rd nd νd ER
Object ∞ ∞
1 69.500 1.25 1.80810 22.76 17.50
2 30.782 1.24 1.70000 17.00 15.72
3 39.414 4.22 1.49700 81.54 15.65
4 54830.052 0.10 15.50
5 36.565 3.57 1.63246 63.76 15.21
6 160.922 Variable 15.00
7 53.792 1.10 1.88300 40.76 9.09
8 7.556 4.79 6.45
9 -46.254 0.80 1.88300 40.76 6.36
10 12.396 0.01 1.51400 42.83 6.37
11 12.396 4.87 1.78472 25.68 6.37
12 -12.684 1.15 6.42
13 -11.499 0.80 1.77250 49.60 5.71
14 ^* -163.375 Variable 5.76
15 (Aperture) ∞ 1.30 3.94
16 ^* 10.743 4.93 1.58913 61.14 4.60
17 -78.051 0.10 4.61
18 28.041 2.77 1.84666 23.78 4.59
19 10.632 1.42 4.28
20 14.230 3.12 1.49700 81.54 4.55
21 -36.985 0.64 4.60
22 ^* 65.138 1.36 1.53071 55.69 4.57
23 ^* 34.607 Variable 4.57
24 19.130 2.68 1.49700 81.54 4.84
25 -119.090 0.01 1.51400 42.83 4.71
26 -119.090 0.82 1.80400 46.57 4.71
27 76.031 Variable 4.66
28 ^* 147.374 1.63 1.53071 55.69 4.16
29 ^* -67.939 1.09 4.07
30 ∞ 4.00 1.51680 64.20 4.01
31 ∞ 1.06 3.84
Image plane ∞

Aspheric data 14th surface
K = 0.000
A2 = 0.0000E + 00, A4 = -9.19823e-05, A6 = -8.80923e-07, A8 = 4.39702e-08, A10 = -1.24247e-09
16th page
K = 0.000
A2 = 0.0000E + 00, A4 = -8.77784e-05, A6 = -1.01116e-06, A8 = 5.64180e-08, A10 = -2.23368e-09,
A12 = 3.59187e-11
22nd page
K = 0.000
A2 = 0.0000E + 00, A4 = -2.17277e-04, A6 = 5.36299e-06, A8 = -5.28517e-07, A10 = 1.10330e-08,
A12 = -1.37250e-10
23rd page
K = 0.000
A2 = 0.0000E + 00, A4 = -1.09771e-04, A6 = 5.91402e-06, A8 = -5.09130e-07, A10 = 8.38419e-09,
A12 = -4.36735e-11
28th page
K = 0.000
A2 = 0.0000E + 00, A4 = 8.15873e-04, A6 = 4.82675e-06, A8 = -2.20386e-06, A10 = 4.10510e-08
29th page
K = 0.000
A2 = 0.0000E + 00, A4 = 1.26016e-03, A6 = 1.60282e-05, A8 = -3.90922e-06, A10 = 7.56282e-08

Various data zoom ratio 19.35
Wide angle Medium Telephoto focal length 4.73 19.71 91.55
FNO. 2.65 3.86 3.92
Angle of view 2ω 76.67 20.09 4.39
Image height 3.6 3.6 3.6
Total lens length 82.59 101.51 116.35
BF 4.78 4.67 4.64

d6 1.00 21.88 42.48
d14 25.16 9.09 2.30
d23 1.29 8.78 10.30
d27 5.70 12.42 11.96

Entrance pupil position 18.68 72.96 365.56
Exit pupil position A -31.42 -78.06 -86.62
Exit pupil position B -36.20 -82.73 -91.26
Front principal point 22.79 87.98 365.26
Rear principal point position -3.68 -18.76 -90.64

Single lens data lens Start surface Focal length
L1 1 -69.38
L2 2 189.59
L3 3 79.36
L4 5 73.99
L5 7 -10.07
L6 9 -11.00
L7 10 8.81E + 04
L8 11 8.73
L9 13 -16.05
L10 16 16.37
L11 18 -21.82
L12 20 21.10
L13 22 -141.31
L14 24 33.38
L15 25 8.13E + 06
L16 26 -57.61
L17 28 87.85

Zoom lens group data group Start surface Focal length Lens configuration length Front principal point position Rear principal point position
1 1 61.3953 10.3740 2.4935 -4.0821
2 7 -7.0582 13.5160 1.9369 -7.0177
3 15 17.2656 15.6380 1.5888 -9.6007
4 24 73.7783 3.5080 -2.0985 -4.2304
5 28 87.8520 6.7160 0.7294 -4.0624

Group Start surface Wide angle magnification Medium magnification Telephoto magnification
1 1 0.0000 0.0000 0.0000
2 7 -0.1492 -0.2670 -1.2089
3 15 -0.7016 -1.8410 -1.8702
4 24 0.7818 0.6924 0.6991
5 28 0.9417 0.9430 0.9434

Numerical example 6
Unit mm

Surface data surface number rd nd νd ER
Object ∞ ∞
1 62.800 2.48 1.92286 18.90 18.30
2 30.887 1.51 1.73000 15.00 17.25
3 39.169 5.31 1.51823 58.90 17.14
4 -627.430 0.10 15.50
5 32.048 3.93 1.64000 60.08 15.19
6 122.361 Variable 15.00
7 86.349 1.10 1.88300 40.76 8.93
8 7.578 4.79 6.23
9 -46.254 0.80 1.88300 40.76 5.96
10 12.396 0.01 1.51400 42.83 5.86
11 12.396 4.87 1.78472 25.68 5.86
12 -12.684 1.15 5.90
13 -11.499 0.80 1.77250 49.60 5.29
14 ^* -223.647 Variable 5.32
15 (Aperture) ∞ 1.30 3.94
16 ^* 10.743 4.93 1.58913 61.14 4.60
17 -78.051 0.10 4.61
18 28.041 2.77 1.84666 23.78 4.59
19 10.632 1.42 4.28
20 14.230 3.12 1.49700 81.54 4.55
21 -36.985 0.64 4.60
22 ^* 75.399 1.36 1.53071 55.69 4.57
23 ^* 34.607 Variable 4.58
24 19.130 2.68 1.49700 81.54 4.80
25 -119.090 0.01 1.51400 42.83 4.68
26 -119.090 0.82 1.80400 46.57 4.68
27 76.031 Variable 4.64
28 ^* 147.374 1.63 1.53071 55.69 4.14
29 ^* -67.939 1.09 4.06
30 ∞ 4.00 1.51680 64.20 4.00
31 ∞ 0.97 3.84
Image plane ∞

Aspheric data 14th surface
K = 0.000
A2 = 0.0000E + 00, A4 = -9.19823e-05, A6 = -8.80923e-07, A8 = 4.39702e-08, A10 = -1.24247e-09
16th page
K = 0.000
A2 = 0.0000E + 00, A4 = -8.77784e-05, A6 = -1.01116e-06, A8 = 5.64180e-08, A10 = -2.23368e-09,
A12 = 3.59187e-11
22nd page
K = 0.000
A2 = 0.0000E + 00, A4 = -2.17277e-04, A6 = 5.36299e-06, A8 = -5.28517e-07, A10 = 1.10330e-08,
A12 = -1.37250e-10
23rd page
K = 0.000
A2 = 0.0000E + 00, A4 = -1.09771e-04, A6 = 5.91402e-06, A8 = -5.09130e-07, A10 = 8.38419e-09,
A12 = -4.36735e-11
28th page
K = 0.000
A2 = 0.0000E + 00, A4 = 8.15873e-04, A6 = 4.82675e-06, A8 = -2.20386e-06, A10 = 4.10510e-08
29th page
K = 0.000
A2 = 0.0000E + 00, A4 = 1.26016e-03, A6 = 1.60282e-05, A8 = -3.90922e-06, A10 = 7.56282e-08

Various data zoom ratio 19.87
Wide angle Medium Telephoto focal length 4.68 19.29 92.93
FNO. 2.69 3.82 3.97
Angle of view 2ω 77.36 20.54 4.33
Image height 3.6 3.6 3.6
Total lens length 86.66 101.23 112.35
BF 4.70 4.69 4.70

d6 1.00 18.85 35.56
d14 26.09 9.99 2.30
d23 1.29 6.60 8.83
d27 5.95 13.47 13.35

Entrance pupil position 21.18 73.90 337.46
Exit pupil position A -31.58 -68.65 -80.95
Exit pupil position B -36.28 -73.34 -85.64
Front principal point position 25.25 88.12 329.55
Rear principal point position -3.71 -18.32 -91.96

Single lens data lens Start surface Focal length
L1 1 -68.41
L2 2 185.77
L3 3 71.34
L4 5 66.71
L5 7 -9.47
L6 9 -11.00
L7 10 8.81E + 04
L8 11 8.73
L9 13 -15.72
L10 16 16.37
L11 18 -21.82
L12 20 21.10
L13 22 -121.94
L14 24 33.38
L15 25 8.13E + 06
L16 26 -57.61
L17 28 87.85

Zoom lens group data group Start surface Focal length Lens configuration length Front principal point position Rear principal point position
1 1 53.8598 13.3306 3.2158 -5.0784
2 7 -6.5877 13.5160 1.8976 -6.9725
3 15 17.4353 15.6380 1.4155 -9.6864
4 24 73.7783 3.5080 -2.0985 -4.2304
5 28 87.8520 6.7160 0.7294 -4.0624

Group Start surface Wide angle magnification Medium magnification Telephoto magnification
1 1 0.0000 0.0000 0.0000
2 7 -0.1676 -0.3071 -1.3903
3 15 -0.7048 -1.8250 -1.9374
4 24 0.7797 0.6779 0.6795
5 28 0.9427 0.9427 0.9427

Numerical example 7
Unit mm

Surface data surface number rd nd νd ER
Object ∞ ∞
1 65.000 1.24 1.90680 21.15 17.50
2 30.035 1.51 1.70010 17.01 15.79
3 40.312 4.21 1.49700 81.54 15.69
4 906535.175 0.10 15.50
5 34.058 3.95 1.64000 60.08 15.23
6 177.217 Variable 15.00
7 56.111 1.10 1.88300 40.76 9.02
8 7.464 4.79 6.37
9 -46.254 0.80 1.88300 40.76 6.28
10 12.396 0.01 1.51400 42.83 6.28
11 12.396 4.87 1.78472 25.68 6.28
12 -12.684 1.15 6.33
13 -11.499 0.80 1.77250 49.60 5.64
14 ^* -167.135 Variable 5.69
15 (Aperture) ∞ 1.30 3.94
16 ^* 10.743 4.93 1.58913 61.14 4.60
17 -78.051 0.10 4.60
18 28.041 2.77 1.84666 23.78 4.58
19 10.632 1.42 4.27
20 14.230 3.12 1.49700 81.54 4.54
21 -36.985 0.64 4.59
22 ^* 75.391 1.36 1.53071 55.69 4.56
23 ^* 34.607 Variable 4.56
24 19.130 2.68 1.49700 81.54 4.82
25 -119.090 0.01 1.51400 42.83 4.70
26 -119.090 0.82 1.80400 46.57 4.70
27 76.031 Variable 4.65
28 ^* 147.374 1.63 1.53071 55.69 4.14
29 ^* -67.939 1.09 4.05
30 ∞ 4.00 1.51680 64.20 3.99
31 ∞ 1.03 3.84
Image plane ∞

Aspheric data 14th surface
K = 0.000
A2 = 0.0000E + 00, A4 = -9.19823e-05, A6 = -8.80923e-07, A8 = 4.39702e-08, A10 = -1.24247e-09
16th page
K = 0.000
A2 = 0.0000E + 00, A4 = -8.77784e-05, A6 = -1.01116e-06, A8 = 5.64180e-08, A10 = -2.23368e-09,
A12 = 3.59187e-11
22nd page
K = 0.000
A2 = 0.0000E + 00, A4 = -2.17277e-04, A6 = 5.36299e-06, A8 = -5.28517e-07, A10 = 1.10330e-08,
A12 = -1.37250e-10
23rd page
K = 0.000
A2 = 0.0000E + 00, A4 = -1.09771e-04, A6 = 5.91402e-06, A8 = -5.09130e-07, A10 = 8.38419e-09,
A12 = -4.36735e-11
28th page
K = 0.000
A2 = 0.0000E + 00, A4 = 8.15873e-04, A6 = 4.82675e-06, A8 = -2.20386e-06, A10 = 4.10510e-08
29th page
K = 0.000
A2 = 0.0000E + 00, A4 = 1.26016e-03, A6 = 1.60282e-05, A8 = -3.90922e-06, A10 = 7.56282e-08

Various data zoom ratio 19.38
Wide angle Medium telephoto focal length 4.77 19.30 92.38
FNO. 2.70 3.84 4.00
Angle of view 2ω 76.06 20.50 4.35
Image height 3.6 3.6 3.6
Total lens length 83.78 100.95 114.80
BF 4.76 4.70 4.76

d6 1.00 20.75 39.70
d14 25.44 9.73 2.30
d23 1.33 7.55 10.06
d27 5.95 12.92 12.68

Entrance pupil position 19.14 72.54 346.58
Exit pupil position A -31.66 -71.85 -86.80
Exit pupil position B -36.42 -76.55 -91.56
Front principal point 23.29 86.98 345.75
Rear principal point position -3.74 -18.32 -91.35

Single lens data lens Start surface Focal length
L1 1 -62.63
L2 2 158.66
L3 3 81.11
L4 5 65.17
L5 7 -9.86
L6 9 -11.00
L7 10 8.81E + 04
L8 11 8.73
L9 13 -16.02
L10 16 16.37
L11 18 -21.82
L12 20 21.10
L13 22 -121.95
L14 24 33.38
L15 25 8.13E + 06
L16 26 -57.61
L17 28 87.85

Zoom lens group data group Start surface Focal length Lens configuration length Front principal point position Rear principal point position
1 1 58.1432 11.0180 2.7809 -4.1469
2 7 -6.9234 13.5160 1.9148 -7.0295
3 15 17.4352 15.6380 1.4156 -9.6863
4 24 73.7783 3.5080 -2.0985 -4.2304
5 28 87.8520 6.7160 0.7294 -4.0624

Group Start surface Wide angle magnification Medium magnification Telephoto magnification
1 1 0.0000 0.0000 0.0000
2 7 -0.1568 -0.2837 -1.2677
3 15 -0.7128 -1.8119 -1.9351
4 24 0.7789 0.6852 0.6876
5 28 0.9420 0.9426 0.9420

Numerical example 8
Unit mm

Surface data surface number rd nd νd ER
Object ∞ ∞
1 58.500 2.40 1.92286 20.88 18.00
2 31.247 1.49 1.70010 17.01 17.33
3 39.455 5.22 1.49700 81.54 17.22
4 -963.692 0.10 15.50
5 32.658 3.81 1.63246 63.76 15.19
6 123.526 Variable 15.00
7 80.785 1.10 1.88300 40.76 9.11
8 7.591 4.79 6.33
9 -46.254 0.80 1.88300 40.76 6.11
10 12.396 0.01 1.51400 42.83 5.97
11 12.396 4.87 1.78472 25.68 5.97
12 -12.684 1.15 5.93
13 -11.499 0.80 1.77250 49.60 5.29
14 ^* -235.968 Variable 5.32
15 (Aperture) ∞ 1.30 3.94
16 ^* 10.743 4.93 1.58913 61.14 4.60
17 -78.051 0.10 4.60
18 28.041 2.77 1.84666 23.78 4.58
19 10.632 1.42 4.28
20 14.230 3.12 1.49700 81.54 4.55
21 -36.985 0.64 4.59
22 ^* 75.823 1.36 1.53071 55.69 4.56
23 ^* 34.607 Variable 4.57
24 19.130 2.68 1.49700 81.54 4.82
25 -119.090 0.01 1.51400 42.83 4.70
26 -119.090 0.82 1.80400 46.57 4.70
27 76.031 Variable 4.65
28 ^* 147.374 1.63 1.53071 55.69 4.14
29 ^* -67.939 1.09 4.06
30 ∞ 4.00 1.51680 64.20 4.00
31 ∞ 1.01 3.84
Image plane ∞

Aspheric data 14th surface
K = 0.000
A2 = 0.0000E + 00, A4 = -9.19823e-05, A6 = -8.80923e-07, A8 = 4.39702e-08, A10 = -1.24247e-09
16th page
K = 0.000
A2 = 0.0000E + 00, A4 = -8.77784e-05, A6 = -1.01116e-06, A8 = 5.64180e-08, A10 = -2.23368e-09,
A12 = 3.59187e-11
22nd page
K = 0.000
A2 = 0.0000E + 00, A4 = -2.17277e-04, A6 = 5.36299e-06, A8 = -5.28517e-07, A10 = 1.10330e-08,
A12 = -1.37250e-10
23rd page
K = 0.000
A2 = 0.0000E + 00, A4 = -1.09771e-04, A6 = 5.91402e-06, A8 = -5.09130e-07, A10 = 8.38419e-09,
A12 = -4.36735e-11
28th page
K = 0.000
A2 = 0.0000E + 00, A4 = 8.15873e-04, A6 = 4.82675e-06, A8 = -2.20386e-06, A10 = 4.10510e-08
29th page
K = 0.000
A2 = 0.0000E + 00, A4 = 1.26016e-03, A6 = 1.60282e-05, A8 = -3.90922e-06, A10 = 7.56282e-08

Various data zoom ratio 19.83
Wide angle Medium telephoto focal length 4.68 19.29 92.91
FNO. 2.69 3.81 4.06
Angle of view 2ω 77.24 20.54 4.33
Image height 3.6 3.6 3.6
Total lens length 86.39 101.63 113.69
BF 4.74 4.72 4.73

d6 1.00 19.45 36.13
d14 26.13 10.19 2.30
d23 1.31 6.96 9.11
d27 5.90 13.00 14.11

Entrance pupil position 21.11 75.92 333.28
Exit pupil position A -31.52 -68.98 -85.70
Exit pupil position B -36.26 -73.70 -90.43
Front principal point position 25.19 90.16 330.73
Rear principal point position -3.67 -18.30 -91.91

Single lens data lens Start surface Focal length
L1 1 -75.89
L2 2 199.64
L3 3 76.40
L4 5 69.07
L5 7 -9.56
L6 9 -11.00
L7 10 8.81E + 04
L8 11 8.73
L9 13 -15.67
L10 16 16.37
L11 18 -21.82
L12 20 21.10
L13 22 -121.35
L14 24 33.38
L15 25 8.13E + 06
L16 26 -57.61
L17 28 87.85

Zoom lens group data group Start surface Focal length Lens configuration length Front principal point position Rear principal point position
1 1 54.9139 13.0201 3.0049 -5.1808
2 7 -6.6219 13.5160 1.9195 -6.9448
3 15 17.4414 15.6380 1.4093 -9.6895
4 24 73.7783 3.5080 -2.0985 -4.2304
5 28 87.8520 6.7160 0.7294 -4.0624

Group Start surface Wide angle magnification Medium magnification Telephoto magnification
1 1 0.0000 0.0000 0.0000
2 7 -0.1648 -0.3045 -1.3073
3 15 -0.7046 -1.7905 -2.0539
4 24 0.7799 0.6838 0.6687
5 28 0.9423 0.9424 0.9423

Numerical example 9
Unit mm

Surface data surface number rd nd νd ER
Object ∞ ∞
1 59.000 1.79 1.80810 22.76 18.20
2 31.331 1.28 1.63336 23.36 16.26
3 39.158 4.66 1.49700 81.54 16.14
4 101891.855 0.10 15.50
5 34.060 3.31 1.64000 60.08 14.35
6 114.503 Variable 14.00
7 63.862 1.10 1.88300 40.76 9.33
8 7.573 4.79 6.51
9 -46.254 0.80 1.88300 40.76 6.42
10 12.396 0.01 1.51400 42.83 6.42
11 12.396 4.87 1.78472 25.68 6.43
12 -12.684 1.15 6.47
13 -11.499 0.80 1.77250 49.60 5.70
14 ^* -239.828 Variable 5.74
15 (Aperture) ∞ 1.30 3.94
16 ^* 10.743 4.93 1.58913 61.14 4.59
17 -78.051 0.10 4.60
18 28.041 2.77 1.84666 23.78 4.57
19 10.632 1.42 4.27
20 14.230 3.12 1.49700 81.54 4.53
21 -36.985 0.64 4.58
22 ^* 80.887 1.36 1.53071 55.69 4.55
23 ^* 34.607 Variable 4.55
24 19.130 2.68 1.49700 81.54 4.80
25 -119.090 0.01 1.51400 42.83 4.68
26 -119.090 0.82 1.80400 46.57 4.68
27 76.031 Variable 4.63
28 ^* 147.374 1.63 1.53071 55.69 4.13
29 ^* -67.939 1.09 4.05
30 ∞ 4.00 1.51680 64.20 3.99
31 ∞ 0.97 3.84
Image plane ∞

Aspheric data 14th surface
K = 0.000
A2 = 0.0000E + 00, A4 = -9.19823e-05, A6 = -8.80923e-07, A8 = 4.39702e-08, A10 = -1.24247e-09
16th page
K = 0.000
A2 = 0.0000E + 00, A4 = -8.77784e-05, A6 = -1.01116e-06, A8 = 5.64180e-08, A10 = -2.23368e-09,
A12 = 3.59187e-11
22nd page
K = 0.000
A2 = 0.0000E + 00, A4 = -2.17277e-04, A6 = 5.36299e-06, A8 = -5.28517e-07, A10 = 1.10330e-08,
A12 = -1.37250e-10
23rd page
K = 0.000
A2 = 0.0000E + 00, A4 = -1.09771e-04, A6 = 5.91402e-06, A8 = -5.09130e-07, A10 = 8.38419e-09,
A12 = -4.36735e-11
28th page
K = 0.000
A2 = 0.0000E + 00, A4 = 8.15873e-04, A6 = 4.82675e-06, A8 = -2.20386e-06, A10 = 4.10510e-08
29th page
K = 0.000
A2 = 0.0000E + 00, A4 = 1.26016e-03, A6 = 1.60282e-05, A8 = -3.90922e-06, A10 = 7.56282e-08

Various data zoom ratio 19.87
Wide angle Medium telephoto focal length 4.68 19.29 92.90
FNO. 2.70 3.82 4.00
Angle of view 2ω 77.39 20.56 4.33
Image height 3.6 3.6 3.6
Total lens length 84.77 101.03 112.41
BF 4.70 4.69 4.70

d6 1.00 20.41 37.78
d14 26.39 10.44 2.30
d23 1.27 7.49 7.58
d27 5.98 12.56 14.63

Entrance pupil position 19.71 75.82 340.35
Exit pupil position A -31.43 -70.07 -77.54
Exit pupil position B -36.13 -74.76 -82.24
Front principal point position 23.78 90.13 328.31
Rear principal point position -3.70 -18.33 -91.92

Single lens data lens Start surface Focal length
L1 1 -85.13
L2 2 232.73
L3 3 78.82
L4 5 74.56
L5 7 -9.82
L6 9 -11.00
L7 10 8.81E + 04
L8 11 8.73
L9 13 -15.66
L10 16 16.37
L11 18 -21.82
L12 20 21.10
L13 22 -115.14
L14 24 33.38
L15 25 8.13E + 06
L16 26 -57.61
L17 28 87.85

Zoom lens group data group Start surface Focal length Lens configuration length Front principal point position Rear principal point position
1 1 56.2753 11.1418 2.4952 -4.5895
2 7 -6.7699 13.5160 1.9676 -6.9046
3 15 17.5094 15.6380 1.3398 -9.7238
4 24 73.7783 3.5080 -2.0985 -4.2304
5 28 87.8520 6.7160 0.7294 -4.0624

Group Start surface Wide angle magnification Medium magnification Telephoto magnification
1 1 0.0000 0.0000 0.0000
2 7 -0.1614 -0.3004 -1.3104
3 15 -0.7007 -1.7540 -2.0181
4 24 0.7794 0.6902 0.6621
5 28 0.9427 0.9427 0.9427

Numerical example 10
Unit mm

Surface data surface number rd nd νd ER
Object ∞ ∞
1 60.982 5.35 1.64850 53.02 24.00
2 495.744 0.19 23.38
3 31.172 1.28 1.92286 18.90 17.70
4 22.227 1.77 1.63387 23.38 16.35
5 26.877 5.23 1.49700 81.54 16.31
6 101.913 Variable 16.00
7 303.814 1.10 1.88300 40.76 9.68
8 8.312 4.79 6.82
9 -46.254 0.80 1.88300 40.76 6.71
10 12.396 0.01 1.51400 42.83 6.69
11 12.396 4.87 1.78472 25.68 6.69
12 -12.684 1.15 6.72
13 -11.499 0.80 1.77250 49.60 5.72
14 ^* -230.432 Variable 5.72
15 (Aperture) ∞ 1.30 3.39
16 ^* 10.743 4.93 1.58913 61.14 3.96
17 -78.051 0.10 4.06
18 28.041 2.77 1.84666 23.78 4.07
19 10.295 1.42 3.87
20 12.826 3.12 1.49700 81.54 4.21
21 -36.985 0.64 4.29
22 ^* 39.207 1.36 1.53071 55.69 4.29
23 ^* 33.196 Variable 4.28
24 19.130 2.68 1.49700 81.54 4.60
25 -119.090 0.01 1.51400 42.83 4.47
26 -119.090 0.82 1.80400 46.57 4.47
27 76.031 Variable 4.41
28 ^* 147.374 1.63 1.53071 55.69 4.17
29 ^* -67.939 1.09 4.09
30 ∞ 4.00 1.51680 64.20 4.02
31 ∞ 1.05 3.85
Image plane ∞

Aspheric data 14th surface
K = 0.000
A2 = 0.0000E + 00, A4 = -7.99095e-05, A6 = -9.37486e-07, A8 = 4.32991e-08, A10 = -1.00218e-09
16th page
K = 0.000
A2 = 0.0000E + 00, A4 = -8.77784e-05, A6 = -1.01116e-06, A8 = 5.64180e-08, A10 = -2.23368e-09,
A12 = 3.59187e-11
22nd page
K = 0.000
A2 = 0.0000E + 00, A4 = -2.17277e-04, A6 = 5.36299e-06, A8 = -5.28517e-07, A10 = 1.10330e-08,
A12 = -1.37250e-10
23rd page
K = 0.000
A2 = 0.0000E + 00, A4 = -1.09771e-04, A6 = 5.91402e-06, A8 = -5.09130e-07, A10 = 8.38419e-09,
A12 = -4.36735e-11
28th page
K = 0.000
A2 = 0.0000E + 00, A4 = 8.15873e-04, A6 = 4.82675e-06, A8 = -2.20386e-06, A10 = 4.10510e-08
29th page
K = 0.000
A2 = 0.0000E + 00, A4 = 1.26016e-03, A6 = 1.60282e-05, A8 = -3.90922e-06, A10 = 7.56282e-08

Various data zoom ratio 17.36
Wide angle Medium Telephoto focal length 4.86 20.12 84.44
FNO. 2.83 4.26 5.31
Angle of view 2ω 75.01 19.69 4.72
Image height 3.6 3.6 3.6
Total lens length 84.06 98.77 118.56
BF 4.78 4.67 4.67

d6 1.00 16.79 33.06
d14 24.28 7.94 2.30
d23 1.62 13.90 29.38
d27 4.26 7.36 1.04

Entrance pupil position 24.63 73.25 271.77
Exit pupil position A -31.43 -104.20 3257.46
Exit pupil position B -36.21 -108.87 3252.79
Front principal point position 28.84 89.66 358.40
Rear principal point position -3.81 -19.17 -83.49

Single lens data lens Start surface Focal length
L1 1 106.71
L2 3 -90.15
L3 4 176.57
L4 5 71.79
L5 7 -9.69
L6 9 -11.00
L7 10 8.81E + 04
L8 11 8.73
L9 13 -15.69
L10 16 16.37
L11 18 -20.69
L12 20 19.57
L13 22 -442.74
L14 24 33.38
L15 25 8.13E + 06
L16 26 -57.61
L17 28 87.85

Zoom lens group data group Start surface Focal length Lens configuration length Front principal point position Rear principal point position
1 1 58.8815 13.8227 -1.3148 -9.6007
2 7 -6.7026 13.5160 1.8901 -6.9662
3 15 16.3471 15.6380 2.4850 -9.1335
4 24 73.7783 3.5080 -2.0985 -4.2304
5 28 87.8520 6.7160 0.7294 -4.0624

Group Start surface Wide angle magnification Medium magnification Telephoto magnification
1 1 0.0000 0.0000 0.0000
2 7 -0.1689 -0.2804 -0.8784
3 15 -0.6482 -1.6981 -2.0449
4 24 0.8014 0.7610 0.8466
5 28 0.9418 0.9430 0.9430

Numerical Example 11
Unit mm

Surface data surface number rd nd νd ER
Object ∞ ∞
1 59.963 4.20 1.49700 81.54 18.60
2 2486.142 0.10 17.76
3 41.700 0.99 1.84666 23.78 15.50
4 25.367 0.72 1.63387 23.38 14.76
5 28.640 4.19 1.67790 55.34 14.74
6 111.334 Variable 14.50
7 110.422 1.10 1.88300 40.76 9.11
8 8.083 4.79 6.49
9 -46.254 0.80 1.88300 40.76 6.24
10 12.396 0.01 1.51400 42.83 6.10
11 12.396 4.87 1.78472 25.68 6.11
12 -12.684 1.15 6.07
13 -11.499 0.80 1.77250 49.60 5.08
14 ^* -125.405 Variable 5.00
15 (Aperture) ∞ 1.30 3.48
16 ^* 10.743 4.93 1.58913 61.14 4.07
17 -78.051 0.10 4.16
18 28.041 2.77 1.84666 23.78 4.16
19 10.469 1.42 3.94
20 13.611 3.12 1.49700 81.54 4.25
21 -36.985 0.64 4.33
22 ^* 63.868 1.36 1.53071 55.69 4.33
23 ^* 48.855 Variable 4.34
24 19.130 2.68 1.49700 81.54 4.65
25 -119.090 0.01 1.51400 42.83 4.51
26 -119.090 0.82 1.80400 46.57 4.51
27 76.031 Variable 4.46
28 ^* 147.374 1.63 1.53071 55.69 4.21
29 ^* -67.939 1.09 4.18
30 ∞ 4.00 1.51680 64.20 4.09
31 ∞ 1.05 3.86
Image plane ∞

Aspheric data 14th surface
K = 0.000
A2 = 0.0000E + 00, A4 = -8.14579e-05, A6 = -1.15665e-06, A8 = 6.76342e-08, A10 = -1.49231e-09
16th page
K = 0.000
A2 = 0.0000E + 00, A4 = -8.77784e-05, A6 = -1.01116e-06, A8 = 5.64180e-08, A10 = -2.23368e-09,
A12 = 3.59187e-11
22nd page
K = 0.000
A2 = 0.0000E + 00, A4 = -2.17277e-04, A6 = 5.36299e-06, A8 = -5.28517e-07, A10 = 1.10330e-08,
A12 = -1.37250e-10
23rd page
K = 0.000
A2 = 0.0000E + 00, A4 = -1.09771e-04, A6 = 5.91402e-06, A8 = -5.09130e-07, A10 = 8.38419e-09,
A12 = -4.36735e-11
28th page
K = 0.000
A2 = 0.0000E + 00, A4 = 6.47771e-04, A6 = -1.69732e-05, A8 = -9.26628e-07, A10 = 1.17663e-08
29th page
K = 0.000
A2 = 0.0000E + 00, A4 = 1.08506e-03, A6 = -2.70703e-05, A8 = -1.53201e-06, A10 = 3.10909e-08

Various data zoom ratio 17.81
Wide angle Medium Telephoto focal length 4.69 19.67 83.55
FNO. 2.80 4.36 5.11
Angle of view 2ω 78.31 20.25 4.80
Image height 3.6 3.6 3.6
Total lens length 80.70 98.74 120.58
BF 4.78 4.68 4.76

d6 1.00 18.72 39.47
d14 24.31 7.57 2.30
d23 1.61 16.43 28.30
d27 4.52 6.85 1.26

Entrance pupil position 19.50 63.53 285.65
Exit pupil position A -31.80 -132.93 -3328.09
Exit pupil position B -36.58 -137.61 -3332.85
Front principal point position 23.59 80.39 367.10
Rear principal point position -3.64 -18.72 -82.51

Single lens data lens Start surface Focal length
L1 1 123.56
L2 3 -78.69
L3 4 322.68
L4 5 55.74
L5 7 -9.93
L6 9 -11.00
L7 10 8.81E + 04
L8 11 8.73
L9 13 -16.44
L10 16 16.37
L11 18 -21.27
L12 20 20.44
L13 22 -404.32
L14 24 33.38
L15 25 8.13E + 06
L16 26 -57.61
L17 28 87.85

Zoom lens group data group Start surface Focal length Lens configuration length Front principal point position Rear principal point position
1 1 63.1420 10.1987 -0.1462 -6.3764
2 7 -7.1131 13.5160 1.8043 -7.2056
3 15 16.6070 15.6380 2.4030 -9.2287
4 24 73.7783 3.5080 -2.0985 -4.2304
5 28 87.8520 6.7160 0.7294 -4.0624

Group Start surface Wide angle magnification Medium magnification Telephoto magnification
1 1 0.0000 0.0000 0.0000
2 7 -0.1518 -0.2442 -0.8487
3 15 -0.6511 -1.7625 -1.9650
4 24 0.7980 0.7677 0.8423
5 28 0.9418 0.9429 0.9420

Numerical Example 12
Unit mm

Surface data surface number rd nd νd ER
Object ∞ ∞
1 60.578 3.83 1.49700 81.54 18.70
2 1959.863 0.10 18.64
3 44.600 1.01 1.82114 24.06 15.50
4 24.534 0.78 1.67000 20.00 14.71
5 27.767 4.49 1.69350 53.21 14.69
6 126.235 Variable 14.45
7 139.991 1.10 1.88300 40.76 9.75
8 8.467 4.79 6.96
9 -46.254 0.80 1.88300 40.76 6.87
10 12.396 0.01 1.51400 42.83 6.85
11 12.396 4.87 1.78472 25.68 6.86
12 -12.684 1.15 6.88
13 -11.499 0.80 1.77250 49.60 5.80
14 ^* -133.624 Variable 5.79
15 (Aperture) ∞ 1.30 3.48
16 ^* 10.743 4.93 1.58913 61.14 4.03
17 -78.051 0.10 4.09
18 28.041 2.77 1.84666 23.78 4.08
19 10.494 1.42 3.85
20 13.584 3.12 1.49700 81.54 4.13
21 -36.985 0.64 4.19
22 ^* 90.159 1.36 1.53071 55.69 4.18
23 ^* 47.692 Variable 4.19
24 19.130 2.68 1.49700 81.54 4.65
25 -119.090 0.01 1.51400 42.83 4.52
26 -119.090 0.82 1.80400 46.57 4.52
27 76.031 Variable 4.47
28 ^* 147.374 1.63 1.53071 55.69 4.20
29 ^* -67.939 1.09 4.22
30 ∞ 4.00 1.51680 64.20 4.11
31 ∞ 0.97 3.87
Image plane ∞

Aspheric data 14th surface
K = 0.000
A2 = 0.0000E + 00, A4 = -7.27292e-05, A6 = -1.76848e-06, A8 = 1.00411e-07, A10 = -1.83590e-09
16th page
K = 0.000
A2 = 0.0000E + 00, A4 = -8.77784e-05, A6 = -1.01116e-06, A8 = 5.64180e-08, A10 = -2.23368e-09,
A12 = 3.59187e-11
22nd page
K = 0.000
A2 = 0.0000E + 00, A4 = -2.17277e-04, A6 = 5.36299e-06, A8 = -5.28517e-07, A10 = 1.10330e-08,
A12 = -1.37250e-10
23rd page
K = 0.000
A2 = 0.0000E + 00, A4 = -1.09771e-04, A6 = 5.91402e-06, A8 = -5.09130e-07, A10 = 8.38419e-09,
A12 = -4.36735e-11
28th page
K = 0.000
A2 = 0.0000E + 00, A4 = 7.47669e-04, A6 = -3.76060e-05, A8 = -7.34892e-07, A10 = 1.04035e-08
29th page
K = 0.000
A2 = 0.0000E + 00, A4 = 1.22156e-03, A6 = -4.89870e-05, A8 = -1.82037e-06, A10 = 5.14864e-08

Various data zoom ratio 19.90
Wide angle Medium Telephoto focal length 4.68 19.85 93.09
FNO. 2.85 4.45 5.18
Angle of view 2ω 78.27 20.06 4.31
Image height 3.6 3.6 3.6
Total lens length 82.56 99.88 120.82
BF 4.70 4.74 4.73

d6 1.00 18.90 40.08
d14 26.12 8.56 2.30
d23 1.59 16.58 27.97
d27 4.66 6.60 1.25

Entrance pupil position 19.80 65.20 312.38
Exit pupil position A -31.19 -128.84 -1443.88
Exit pupil position B -35.88 -133.58 -1448.62
Front principal point position 23.87 82.10 399.49
Rear principal point position -3.71 -18.83 -92.08

Single lens data lens Start surface Focal length
L1 1 125.69
L2 3 -67.96
L3 4 286.94
L4 5 50.39
L5 7 -10.25
L6 9 -11.00
L7 10 8.81E + 04
L8 11 8.73
L9 13 -16.33
L10 16 16.37
L11 18 -21.35
L12 20 20.41
L13 22 -192.93
L14 24 33.38
L15 25 8.13E + 06
L16 26 -57.61
L17 28 87.85

Zoom lens group data group Start surface Focal length Lens configuration length Front principal point position Rear principal point position
1 1 62.9060 10.2044 -0.1488 -6.3375
2 7 -7.2621 13.5160 1.8474 -7.1449
3 15 16.9381 15.6380 2.0302 -9.4078
4 24 73.7783 3.5080 -2.0985 -4.2304
5 28 87.8520 6.7160 0.7294 -4.0624

Group Start surface Wide angle magnification Medium magnification Telephoto magnification
1 1 0.0000 0.0000 0.0000
2 7 -0.1563 -0.2543 -0.9836
3 15 -0.6330 -1.7097 -1.8942
4 24 0.7973 0.7702 0.8429
5 28 0.9427 0.9422 0.9423

Numerical Example 13
Unit mm

Surface data surface number rd nd νd ER
Object ∞ ∞
1 62.273 3.78 1.49700 81.54 18.70
2 2204.309 0.10 18.81
3 43.400 1.00 1.90680 21.15 15.50
4 24.822 0.83 1.73000 15.00 14.72
5 28.504 4.49 1.69100 54.82 14.71
6 158.244 Variable 14.48
7 179.385 1.10 1.88300 40.76 9.76
8 8.634 4.79 7.01
9 -46.254 0.80 1.88300 40.76 6.91
10 12.396 0.01 1.51400 42.83 6.89
11 12.396 4.87 1.78472 25.68 6.89
12 -12.684 1.15 6.91
13 -11.499 0.80 1.77250 49.60 5.76
14 ^* -124.597 Variable 5.74
15 (Aperture) ∞ 1.30 3.48
16 ^* 10.743 4.93 1.58913 61.14 4.03
17 -78.051 0.10 4.08
18 28.041 2.77 1.84666 23.78 4.08
19 10.545 1.42 3.85
20 13.646 3.12 1.49700 81.54 4.12
21 -36.985 0.64 4.18
22 ^* 84.725 1.36 1.53071 55.69 4.17
23 ^* 42.613 Variable 4.17
24 19.130 2.68 1.49700 81.54 4.61
25 -119.090 0.01 1.51400 42.83 4.48
26 -119.090 0.82 1.80400 46.57 4.48
27 76.031 Variable 4.43
28 ^* 147.374 1.63 1.53071 55.69 4.18
29 ^* -67.939 1.09 4.26
30 ∞ 4.00 1.51680 64.20 4.13
31 ∞ 0.97 3.88
Image plane ∞

Aspheric data 14th surface
K = 0.000
A2 = 0.0000E + 00, A4 = -6.87584e-05, A6 = -1.78351e-06, A8 = 9.24419e-08, A10 = -1.58208e-09
16th page
K = 0.000
A2 = 0.0000E + 00, A4 = -8.77784e-05, A6 = -1.01116e-06, A8 = 5.64180e-08, A10 = -2.23368e-09,
A12 = 3.59187e-11
22nd page
K = 0.000
A2 = 0.0000E + 00, A4 = -2.17277e-04, A6 = 5.36299e-06, A8 = -5.28517e-07, A10 = 1.10330e-08,
A12 = -1.37250e-10
23rd page
K = 0.000
A2 = 0.0000E + 00, A4 = -1.09771e-04, A6 = 5.91402e-06, A8 = -5.09130e-07, A10 = 8.38419e-09,
A12 = -4.36735e-11
28th page
K = 0.000
A2 = 0.0000E + 00, A4 = 6.11134e-04, A6 = -4.92865e-05, A8 = -5.05949e-07, A10 = 2.19323e-09
29th page
K = 0.000, A2 = 0.0000E + 00, A4 = 1.09149e-03, A6 = -6.84436e-05, A8 = -1.26590e-06,
A10 = 4.63882e-08

Various data zoom ratio 19.80
Wide angle Medium Telephoto focal length 4.70 21.07 92.95
FNO. 2.87 4.50 5.22
Angle of view 2ω 77.84 18.91 4.31
Image height 3.6 3.6 3.6
Total lens length 82.94 100.13 120.10
BF 4.69 4.70 4.70

d6 1.00 19.36 39.43
d14 26.54 8.04 2.30
d23 1.58 14.90 27.96
d27 4.65 8.67 1.22

Entrance pupil position 19.80 67.28 303.89
Exit pupil position A -30.80 -116.62 -1286.31
Exit pupil position B -35.49 -121.32 -1291.01
Front principal point position 23.87 84.69 390.16
Rear principal point position -3.73 -20.10 -91.98

Single lens data lens Start surface Focal length
L1 1 128.87
L2 3 -65.62
L3 4 240.41
L4 5 49.61
L5 7 -10.30
L6 9 -11.00
L7 10 8.81E + 04
L8 11 8.73
L9 13 -16.45
L10 16 16.37
L11 18 -21.52
L12 20 20.48
L13 22 -163.38
L14 24 33.38
L15 25 8.13E + 06
L16 26 -57.61
L17 28 87.85

Zoom lens group data group Start surface Focal length Lens configuration length Front principal point position Rear principal point position
1 1 62.0750 10.1939 0.0124 -6.1538
2 7 -7.3388 13.5160 1.8236 -7.1887
3 15 17.0107 15.6380 1.8824 -9.4664
4 24 73.7783 3.5080 -2.0985 -4.2304
5 28 87.8520 6.7160 0.7294 -4.0624

Group Start surface Wide angle magnification Medium magnification Telephoto magnification
1 1 0.0000 0.0000 0.0000
2 7 -0.1604 -0.2678 -1.0014
3 15 -0.6274 -1.8095 -1.8801
4 24 0.7975 0.7430 0.8438
5 28 0.9427 0.9427 0.9427

Numerical example 14
Unit mm

Surface data surface number rd nd νd ER
Object ∞ ∞
1 59.200 3.83 1.49700 81.54 18.70
2 2576.346 0.10 18.48
3 38.400 0.96 1.90680 21.15 15.50
4 23.902 0.77 1.70010 17.01 14.69
5 27.142 4.40 1.69400 56.30 14.68
6 112.392 Variable 14.44
7 124.140 1.10 1.88300 40.76 9.63
8 8.143 4.79 6.79
9 -46.254 0.80 1.88300 40.76 6.71
10 12.396 0.01 1.51400 42.83 6.70
11 12.396 4.87 1.78472 25.68 6.70
12 -12.684 1.15 6.74
13 -11.499 0.80 1.77250 49.60 5.81
14 ^* -141.904 Variable 5.83
15 (Aperture) ∞ 1.30 3.48
16 ^* 10.743 4.93 1.58913 61.14 4.03
17 -78.051 0.10 4.09
18 28.041 2.77 1.84666 23.78 4.09
19 10.545 1.42 3.85
20 13.731 3.12 1.49700 81.54 4.14
21 -36.985 0.64 4.20
22 ^* 81.603 1.36 1.53071 55.69 4.19
23 ^* 44.028 Variable 4.19
24 19.130 2.68 1.49700 81.54 4.62
25 -119.090 0.01 1.51400 42.83 4.50
26 -119.090 0.82 1.80400 46.57 4.50
27 76.031 Variable 4.45
28 ^* 147.374 1.63 1.53071 55.69 4.18
29 ^* -67.939 1.09 4.22
30 ∞ 4.00 1.51680 64.20 4.11
31 ∞ 1.00 3.87
Image plane ∞

Aspheric data 14th surface
K = 0.000
A2 = 0.0000E + 00, A4 = -8.03282e-05, A6 = -9.82748e-07, A8 = 4.48510e-08, A10 = -9.57444e-10
16th page
K = 0.000
A2 = 0.0000E + 00, A4 = -8.77784e-05, A6 = -1.01116e-06, A8 = 5.64180e-08, A10 = -2.23368e-09,
A12 = 3.59187e-11
22nd page
K = 0.000
A2 = 0.0000E + 00, A4 = -2.17277e-04, A6 = 5.36299e-06, A8 = -5.28517e-07, A10 = 1.10330e-08,
A12 = -1.37250e-10
23rd page
K = 0.000
A2 = 0.0000E + 00, A4 = -1.09771e-04, A6 = 5.91402e-06, A8 = -5.09130e-07, A10 = 8.38419e-09,
A12 = -4.36735e-11
28th page
K = 0.000
A2 = 0.0000E + 00, A4 = 1.07507e-03, A6 = -8.98397e-05, A8 = 3.30252e-06, A10 = -1.03838e-07
29th page
K = 0.000
A2 = 0.0000E + 00, A4 = 1.64800e-03, A6 = -1.03700e-04, A8 = 1.95605e-06, A10 = -5.18968e-08

Various data zoom ratio 19.40
Wide angle Medium Telephoto focal length 4.75 21.05 92.07
FNO. 2.88 4.49 5.39
Angle of view 2ω 76.84 18.92 4.35
Image height 3.6 3.6 3.6
Total lens length 82.20 98.86 118.20
BF 4.72 4.70 4.70

d6 1.00 18.05 35.85
d14 25.71 8.05 2.30
d23 1.57 14.67 29.76
d27 4.85 9.04 1.25

Entrance pupil position 19.80 66.10 277.19
Exit pupil position A -31.32 -116.75 3184.27
Exit pupil position B -36.05 -121.45 3179.56
Front principal point 23.92 83.50 371.92
Rear principal point position -3.75 -20.07 -91.09

Single lens data lens Start surface Focal length
L1 1 121.85
L2 3 -72.08
L3 4 260.52
L4 5 50.49
L5 7 -9.91
L6 9 -11.00
L7 10 8.81E + 04
L8 11 8.73
L9 13 -16.24
L10 16 16.37
L11 18 -21.52
L12 20 20.57
L13 22 -182.46
L14 24 33.38
L15 25 8.13E + 06
L16 26 -57.61
L17 28 87.85

Zoom lens group data group Start surface Focal length Lens configuration length Front principal point position Rear principal point position
1 1 57.9678 10.0525 -0.1804 -6.2322
2 7 -7.0320 13.5160 1.8345 -7.1369
3 15 16.9660 15.6380 1.9601 -9.4347
4 24 73.7783 3.5080 -2.0985 -4.2304
5 28 87.8520 6.7160 0.7294 -4.0624

Group Start surface Wide angle magnification Medium magnification Telephoto magnification
1 1 0.0000 0.0000 0.0000
2 7 -0.1680 -0.2833 -1.0020
3 15 -0.6511 -1.8427 -1.9939
4 24 0.7943 0.7378 0.8434
5 28 0.9424 0.9427 0.9426

Numerical example 15
Unit mm

Surface data surface number rd nd νd ER
Object ∞ ∞
1 60.430 4.03 1.49700 81.54 18.70
2 3560.059 0.10 19.11
3 37.900 1.14 1.94595 17.98 15.50
4 24.736 0.73 1.69952 16.99 14.71
5 27.816 4.15 1.72000 43.69 14.69
6 93.987 Variable 14.43
7 96.799 1.10 1.88300 40.76 9.61
8 8.027 4.79 6.69
9 -46.254 0.80 1.88300 40.76 6.54
10 12.396 0.01 1.51400 42.83 6.47
11 12.396 4.87 1.78472 25.68 6.47
12 -12.684 1.15 6.48
13 -11.499 0.80 1.77250 49.60 5.45
14 ^* -173.275 Variable 5.40
15 (Aperture) ∞ 1.30 3.48
16 ^* 10.743 4.93 1.58913 61.14 4.04
17 -78.051 0.10 4.10
18 28.041 2.77 1.84666 23.78 4.10
19 10.392 1.42 3.87
20 13.283 3.12 1.49700 81.54 4.16
21 -36.985 0.64 4.23
22 ^* 77.099 1.36 1.53071 55.69 4.22
23 ^* 46.336 Variable 4.22
24 19.130 2.68 1.49700 81.54 4.67
25 -119.090 0.01 1.51400 42.83 4.54
26 -119.090 0.82 1.80400 46.57 4.54
27 76.031 Variable 4.49
28 ^* 147.374 1.63 1.53071 55.69 4.23
29 ^* -67.939 1.09 4.23
30 ∞ 4.00 1.51680 64.20 4.12
31 ∞ 1.03 3.88
Image plane ∞

Aspheric data 14th surface
K = 0.000
A2 = 0.0000E + 00, A4 = -8.03513e-05, A6 = -1.67633e-06, A8 = 9.30749e-08, A10 = -1.83760e-09
16th page
K = 0.000
A2 = 0.0000E + 00, A4 = -8.77784e-05, A6 = -1.01116e-06, A8 = 5.64180e-08, A10 = -2.23368e-09,
A12 = 3.59187e-11
22nd page
K = 0.000
A2 = 0.0000E + 00, A4 = -2.17277e-04, A6 = 5.36299e-06, A8 = -5.28517e-07, A10 = 1.10330e-08,
A12 = -1.37250e-10
23rd page
K = 0.000
A2 = 0.0000E + 00, A4 = -1.09771e-04, A6 = 5.91402e-06, A8 = -5.09130e-07, A10 = 8.38419e-09,
A12 = -4.36735e-11
28th page
K = 0.000
A2 = 0.0000E + 00, A4 = 6.78553e-04, A6 = -1.66161e-05, A8 = -1.54939e-06, A10 = 2.20507e-08
29th page
K = 0.000
A2 = 0.0000E + 00, A4 = 1.05976e-03, A6 = -1.53037e-05, A8 = -3.28541e-06, A10 = 7.26883e-08

Various data zoom ratio 19.92
Wide angle Medium Telephoto focal length 4.67 20.84 93.13
FNO. 2.85 4.40 5.15
Angle of view 2ω 77.78 19.19 4.33
Image height 3.6 3.6 3.6
Total lens length 81.99 100.29 118.08
BF 4.76 4.75 4.75

d6 1.00 19.61 37.43
d14 25.51 8.65 2.30
d23 1.67 16.59 27.97
d27 4.63 6.26 1.20

Entrance pupil position 19.80 72.63 304.09
Exit pupil position A -31.58 -128.41 -1571.95
Exit pupil position B -36.34 -133.16 -1576.70
Front principal point position 23.87 90.21 391.72
Rear principal point position -3.64 -19.82 -92.11

Single lens data lens Start surface Focal length
L1 1 123.64
L2 3 -78.59
L3 4 291.02
L4 5 53.47
L5 7 -9.97
L6 9 -11.00
L7 10 8.81E + 04
L8 11 8.73
L9 13 -15.98
L10 16 16.37
L11 18 -21.01
L12 20 20.08
L13 22 -222.23
L14 24 33.38
L15 25 8.13E + 06
L16 26 -57.61
L17 28 87.85

Zoom lens group data group Start surface Focal length Lens configuration length Front principal point position Rear principal point position
1 1 59.5217 10.1420 -0.4561 -6.4724
2 7 -6.9701 13.5160 1.9002 -7.0261
3 15 16.8268 15.6380 2.1560 -9.3421
4 24 73.7783 3.5080 -2.0985 -4.2304
5 28 87.8520 6.7160 0.7294 -4.0624

Group Start surface Wide angle magnification Medium magnification Telephoto magnification
1 1 0.0000 0.0000 0.0000
2 7 -0.1614 -0.2837 -1.0326
3 15 -0.6482 -1.6910 -1.9072
4 24 0.7967 0.7748 0.8434
5 28 0.9420 0.9421 0.9421

Numerical Example 16
Unit mm

Surface data

Surface number rd nd νd ER
Object ∞ ∞
1 59.751 3.90 1.49700 81.54 18.70
2 2203.377 0.10 18.75
3 41.900 1.11 1.90680 21.15 15.50
4 25.678 0.80 1.63336 23.36 14.74
5 29.121 4.20 1.72000 46.02 14.71
6 119.744 Variable 14.47
7 129.746 1.10 1.88300 40.76 9.78
8 8.421 4.79 6.95
9 -46.254 0.80 1.88300 40.76 6.86
10 12.396 0.01 1.51400 42.83 6.84
11 12.396 4.87 1.78472 25.68 6.84
12 -12.684 1.15 6.86
13 -11.499 0.80 1.77250 49.60 5.75
14 ^* -149.795 Variable 5.72
15 (Aperture) ∞ 1.30 3.48
16 ^* 10.743 4.93 1.58913 61.14 4.03
17 -78.051 0.10 4.08
18 28.041 2.77 1.84666 23.78 4.08
19 10.386 1.42 3.85
20 13.158 3.12 1.49700 81.54 4.14
21 -36.985 0.64 4.20
22 ^* 87.274 1.36 1.53071 55.69 4.18
23 ^* 44.424 Variable 4.18
24 19.130 2.68 1.49700 81.54 4.63
25 -119.090 0.01 1.51400 42.83 4.49
26 -119.090 0.82 1.80400 46.57 4.49
27 76.031 Variable 4.44
28 ^* 147.374 1.63 1.53071 55.69 4.19
29 ^* -67.939 1.09 4.25
30 ∞ 4.00 1.51680 64.20 4.12
31 ∞ 0.97 3.88
Image plane ∞

Aspheric data 14th surface
K = 0.000
A2 = 0.0000E + 00, A4 = -7.22699e-05, A6 = -1.91912e-06, A8 = 1.03329e-07, A10 = -1.85098e-09
16th page
K = 0.000
A2 = 0.0000E + 00, A4 = -8.77784e-05, A6 = -1.01116e-06, A8 = 5.64180e-08, A10 = -2.23368e-09,
A12 = 3.59187e-11
22nd page
K = 0.000
A2 = 0.0000E + 00, A4 = -2.17277e-04, A6 = 5.36299e-06, A8 = -5.28517e-07, A10 = 1.10330e-08,
A12 = -1.37250e-10
23rd page
K = 0.000
A2 = 0.0000E + 00, A4 = -1.09771e-04, A6 = 5.91402e-06, A8 = -5.09130e-07, A10 = 8.38419e-09,
A12 = -4.36735e-11
28th page
K = 0.000
A2 = 0.0000E + 00, A4 = 3.76463e-04, A6 = -9.67102e-06, A8 = -2.04606e-06, A10 = 2.89575e-08
29th page
K = 0.000
A2 = 0.0000E + 00, A4 = 7.08578e-04, A6 = -8.97430e-06, A8 = -3.63292e-06, A10 = 8.09720e-08

Various data zoom ratio 19.87
Wide angle Medium Telephoto focal length 4.69 20.78 93.18
FNO. 2.86 4.46 5.20
Angle of view 2ω 77.60 19.19 4.31
Image height 3.6 3.6 3.6
Total lens length 82.58 99.94 119.10
BF 4.70 4.69 4.70

d6 1.00 19.14 38.41
d14 26.21 8.39 2.30
d23 1.59 15.72 28.02
d27 4.68 7.59 1.26

Entrance pupil position 19.80 68.12 301.49
Exit pupil position A -31.13 -122.17 -1463.63
Exit pupil position B -35.83 -126.86 -1468.33
Front principal point 23.88 85.50 388.75
Rear principal point position -3.72 -19.81 -92.20

Single lens data lens Start surface Focal length
L1 1 123.50
L2 3 -75.60
L3 4 314.63
L4 5 52.42
L5 7 -10.24
L6 9 -11.00
L7 10 8.81E + 04
L8 11 8.73
L9 13 -16.16
L10 16 16.37
L11 18 -20.99
L12 20 19.94
L13 22 -172.39
L14 24 33.38
L15 25 8.13E + 06
L16 26 -57.61
L17 28 87.85

Zoom lens group data group Start surface Focal length Lens configuration length Front principal point position Rear principal point position
1 1 60.7680 10.1128 -0.1334 -6.2114
2 7 -7.1956 13.5160 1.8818 -7.0797
3 15 16.9487 15.6380 1.9918 -9.4149
4 24 73.7783 3.5080 -2.0985 -4.2304
5 28 87.8520 6.7160 0.7294 -4.0624
Group Start surface Wide angle magnification Medium magnification Telephoto magnification
1 1 0.0000 0.0000 0.0000
2 7 -0.1618 -0.2732 -1.0183
3 15 -0.6350 -1.7527 -1.8946
4 24 0.7969 0.7575 0.8432
5 28 0.9427 0.9427 0.9426

Next, the values of the conditional expressions in each example are listed.

｜ fG1 / fG2 ｜ ＞ 6.4 (2)
0 <(Zb (3.3a) -Za (3.3a)) / (Zb (2.5a) -Za (2.5a)) <0.895 (3-2)
0.387 <(Tnglw (0.7) / Tbasw (0.7)) / (Tngl (0) / Tbas (0)) <0.525 (4-3)
0.4 <θhg _A <1.2 (5)
| f _B / f _A |> 0.15 (6)

(2) (3-2) (4-3) (5) (6)
Example 1 8.29 0.7574 0.393 0.647 0.3560
Example 2 7.85 0.8271 0.438 0.647 0.2503
Example 3 8.04 0.7984 0.521 0.647 0.3333
Example 4 7.44 0.7708 0.480 0.647 0.3136
Example 5 8.70 0.7511 0.413 0.695 0.3659
Example 6 8.18 0.7240 0.507 0.726 0.3683
Example 7 8.40 0.7629 0.407 0.812 0.3948
Example 8 8.29 0.8095 0.524 0.812 0.3801
Example 9 8.31 0.7799 0.495 0.900 0.3658
Example 10 8.78 0.8273 0.511 0.647 0.5105
Example 11 8.88 0.7060 0.485 0.647 0.2439
Example 12 8.66 0.6693 0.434 0.654 0.2368
Example 13 8.46 0.6663 0.441 0.726 0.2730
Example 14 8.24 0.6621 0.454 0.812 0.2767
Example 15 8.54 0.6675 0.512 0.900 0.2701
Example 16 8.45 0.7065 0.503 0.900 0.2403

0 <θgF _B −θgF _BA <0.25 (7)
1.0 <f _A /fG1<8.0 (8)
−25 <(Ra + Rb) / (Ra−Rb) <− 2 (9)

(7) (8) (9)
Example 1 0.0198 4.53 -9.74
Example 2 0.0182 6.04 -13.40
Example 3 0.0244 4.17 -8.99
Example 4 0.0223 4.53 -9.65
Example 5 0.0834 3.09 -8.13
Example 6 0.0762 3.45 -8.46
Example 7 0.1259 2.73 -6.85
Example 8 0.1069 3.64 -8.61
Example 9 0.1033 4.14 -9.01
Example 10 0.0130 3.00 -10.56
Example 11 0.0157 5.11 -16.50
Example 12 0.0264 4.56 -16.18
Example 13 0.0600 3.87 -14.48
Example 14 0.0684 4.49 -15.75
Example 15 0.0651 4.89 -17.06
Example 16 0.0519 5.18 -15.92

0.3 <Tngl (0) / Tbas (0) <3 (10-1a)
0.2 <Tnglt (0.7) / Tbast (0.7) <2.0 (10-1b)
0.1 <Tnglt (0.9) / Tbast (0.9) <1.4 (10-1c)
0.2 <(Tnglt (0.7) / Tbast (0.7)) / (Tngl (0) / Tbas (0)) <0.85 (10-2a)
0.10 <(Tnglt (0.9) / Tbast (0.9)) / (Tngl (0) / Tbas (0)) <0.75 (10-2b)

(10-1a) (10-1b) (10-1c) (10-2a) (10-2b)
Example 1 1.00 0.52 0.35 0.520 0.346
Example 2 0.97 0.53 0.37 0.545 0.385
Example 3 0.67 0.42 0.30 0.622 0.454
Example 4 0.53 0.29 0.18 0.540 0.346
Example 5 0.99 0.41 0.23 0.411 0.230
Example 6 0.61 0.39 0.29 0.645 0.480
Example 7 1.22 0.56 0.35 0.461 0.285
Example 8 0.62 0.41 0.31 0.663 0.502
Example 9 0.71 0.42 0.30 0.588 0.413
Example 10 1.38 0.94 0.74 0.682 0.537
Example 11 0.72 0.37 0.24 0.513 0.337
Example 12 0.77 0.38 0.25 0.497 0.325
Example 13 0.83 0.43 0.29 0.520 0.346
Example 14 0.80 0.46 0.33 0.578 0.412
Example 15 0.64 0.38 0.26 0.585 0.412
Example 16 0.72 0.42 0.30 0.582 0.414

0.5 <(Tnglw (0.7) / (Tngl (0)) <0.95 (11a)
0.3 <(Tnglw (0.9) / (Tngl (0)) <0.85 (11b)
0.5 <(Tnglt (0.7) / (Tngl (0)) <0.95 (12a)
0.3 <(Tnglt (0.9) / (Tngl (0)) <0.9 (12b)

(11a) (11b) (12a) (12b)
Example 1 0.675 0.420 0.775 0.626
Example 2 0.759 0.568 0.829 0.717
Example 3 0.804 0.675 0.804 0.675
Example 4 0.680 0.428 0.727 0.544
Example 5 0.705 0.476 0.700 0.499
Example 6 0.705 0.469 0.808 0.681
Example 7 0.700 0.467 0.744 0.573
Example 8 0.712 0.483 0.810 0.815
Example 9 0.714 0.487 0.783 0.639
Example 10 0.739 0.561 0.851 0.755
Example 11 0.753 0.570 0.765 0.610
Example 12 0.736 0.541 0.776 0.627
Example 13 0.730 0.530 0.783 0.638
Example 14 0.727 0.527 0.811 0.686
Example 15 0.741 0.547 0.789 0.649
Example 16 0.758 0.576 0.806 0.678

0.3 <Tngl (0) / Tbas (0) <2.5 (13-1a)
0.15 <Tnglw (0.7) / Tbasw (0.7) <1.4 (13-1b)
0 <Tnglw (0.9) / Tbasw (0.9) <0.7 (13-1c)
0 <(Tnglw (0.9) / Tbasw (0.9)) / (Tngl (0) / Tbas (0)) <0.5 (13-2)
0 <TG ₄₅ / WG ₄₅ <5… (20)

(13-1a) (13-1b) (13-1c) (13-2) (20)
Example 1 1.00 0.39 0.18 0.185 2.736
Example 2 0.97 0.43 0.24 0.246 1.738
Example 3 0.67 0.35 0.20 0.301 1.165
Example 4 0.53 0.26 0.13 0.246 0.905
Example 5 0.99 0.41 0.21 0.212 2.098
Example 6 0.61 0.31 0.17 0.277 2.242
Example 7 1.22 0.49 0.25 0.205 2.132
Example 8 0.62 0.33 0.18 0.296 2.392
Example 9 0.71 0.35 0.19 0.273 2.448
Example 10 1.38 0.70 0.44 0.320 0.244
Example 11 0.72 0.35 0.21 0.290 0.280
Example 12 0.77 0.33 0.19 0.245 0.268
Example 13 0.83 0.36 0.20 0.247 0.263
Example 14 0.80 0.36 0.21 0.262 0.258
Example 15 0.64 0.33 0.20 0.307 0.259
Example 16 0.72 0.36 0.22 0.305 0.270

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

  FIG. 33 to FIG. 35 are conceptual diagrams of a configuration in which the imaging optical system according to the present invention is incorporated in a photographing optical system 41 of a digital camera. 33 is a front perspective view showing the appearance of the digital camera 40, FIG. 34 is a rear perspective view thereof, and FIG. 35 is a cross-sectional view showing an optical configuration of the digital camera 40.

  In this example, the digital camera 40 includes a photographing optical system 41 having a photographing optical path 42, a finder optical system 43 having a finder optical path 44, a shutter 45, a flash 46, a liquid crystal display monitor 47, and the like. Then, when the photographer presses the shutter 45 disposed on the upper part of the camera 40, photographing is performed through the photographing optical system 41, for example, the imaging optical system 48 of the first embodiment in conjunction therewith.

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

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

  According to the digital camera 40 configured as described above, an electronic imaging apparatus having a compact and thin imaging optical system in which the number of components of the photographing optical system 41 is reduced can be realized. The present invention is not limited to the above-described retractable digital camera, but can also be applied to a folding digital camera that employs a bending optical system.

  Next, a personal computer which is an example of an information processing apparatus in which the imaging optical system of the present invention is built as an objective optical system is shown in FIGS. 36 is a front perspective view of the personal computer 300 with the cover open, FIG. 37 is a sectional view of the photographing optical system 303 of the personal computer 300, and FIG. 38 is a side view of FIG. As shown in FIGS. 36 to 38, the personal computer 300 includes a keyboard 301, information processing means and recording means, a monitor 302, and a photographing optical system 303.

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

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

A cover glass 102 for protecting the objective optical system 100 is disposed at the tip of the mirror frame.
The object image received by the electronic image sensor chip 162 is input to the processing means of the personal computer 300 via the terminal 166. Finally, the object image is displayed on the monitor 302 as an electronic image. FIG. 36 shows an image 305 taken by the operator as an example. The image 305 can also be displayed on a communication partner's personal computer from a remote location via the processing means. The Internet and telephone are used for image transmission to remote places.

  Next, FIG. 39 shows a telephone which is an example of an information processing apparatus in which the imaging optical system of the present invention is incorporated as a photographing optical system, particularly a portable telephone which is convenient to carry. 39A is a front view of the mobile phone 400, FIG. 39B is a side view, and FIG. 39C is a cross-sectional view of the photographing optical system 405. As shown in FIGS. 39A to 39C, the mobile phone 400 includes a microphone unit 401, a speaker unit 402, an input dial 403, a monitor 404, a photographing optical system 405, an antenna 406, and processing. Means.

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

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

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

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

  INDUSTRIAL APPLICABILITY The present invention is useful for an imaging optical system having a good correction of chromatic aberration, a good imaging performance, a wide angle of view and a high zoom ratio, and an electronic imaging apparatus using the imaging optical system.

G1 First lens group G2 Second lens group G3 Third lens group G4 Fourth lens group G5 Fifth lens group L1 to L6, L8 to L14, L16 to L17 Each lens L7, L15 Bonding layer LPF Low pass filter CG Cover glass I Imaging surface E Eyeball of observer 40 Digital camera 41 Imaging optical system 42 Optical path for imaging 43 Viewfinder optical system 44 Optical path for viewfinder 45 Shutter 46 Flash 47 Liquid crystal display monitor 48 Imaging optical system 49 CCD
DESCRIPTION OF SYMBOLS 50 Image pick-up surface 51 Processing means 53 Finder objective optical system 55 Porro prism 57 Field frame 59 Eyepiece optical system 66 Focus lens 67 Imaging surface 100 Objective optical system 102 Cover glass 162 Electronic image pick-up element chip | tip 166 Terminal 300 Personal computer 301 Keyboard 302 Monitor 303 Imaging Optical System 304 Imaging Optical Path 305 Image 400 Mobile Phone 401 Microphone Unit 402 Speaker Unit 403 Input Dial 404 Monitor 405 Imaging Optical System 406 Antenna 407 Imaging Optical Path

Claims (18)

In an electronic imaging apparatus having an imaging optical system and an imaging element,
The imaging optical system includes, in order from the object side to the image side, a first lens group having a positive refractive power, a second lens group having a negative refractive power, and an image side lens group having a positive refractive power. Having an interval between the first lens group and the second lens group during zooming,
A cemented optical element D is provided in the first lens group;
The bonding optical element D is configured such that a refractive optical element A having a positive refractive power is positioned between the optical element B positioned on the object side and the optical element C positioned on the image side,
An electronic imaging apparatus that satisfies the following conditional expression (4-1) conditional expression (4-2) and conditional expression (4-3):
νd _A <30 (4-1)
0.54 <θgF _A <0.9 (4-2)
0.387 <(Tnglw (0.7) / Tbasw (0.7)) / (Tngl (0) / Tbas (0)) <0.525 (4-3)
here,
νd _A is the Abbe number (nd _A -1) / (nF _A -nC _A ) of the refractive optical element A,
θgF _A is a partial dispersion ratio (ng _A −nF _A ) / (nF _A −nC _A ) of the refractive optical element A,
nd _A , nC _A , nF _A , and ng _A are the refractive indexes of the refractive optical element A with respect to the d-line, C-line, F-line, and g-line,
Tngl (0) is the thickness on the axis of the refractive optical element A,
Tnglw (0.7) is the length that a light beam having a light height of 70% with respect to the maximum light beam height on the image sensor at the wide-angle end passes through the refractive optical element A;
Tbas (0) is the thickness on the axis of the optical element B,
Tbasw (0.7) is the length that a light beam having a light height of 70% with respect to the maximum light beam height on the image sensor at the wide-angle end passes through the optical element B;
It is. The electronic imaging apparatus according to claim 1, wherein the following conditional expression (2) is satisfied.
｜ fG1 / fG2 ｜ ＞ 6.4 (2)
here,
fG1 is the focal length of the first lens group,
fG2 is the focal length of the second lens group,
It is. In order from the object side to the image side, a first lens group having a positive refractive power, a second lens group having a negative refractive power, and an image side lens group having a positive refractive power are provided. In an imaging optical system in which the distance between one lens group and the second lens group changes,
A refractive optical element A having a positive refractive power is located in the first lens group,
An imaging optical system that satisfies the following conditional expressions (4-1), (4-2), and (2):
νd _A <30 (4-1)
0.54 <θgF _A <0.9 (4-2)
｜ fG1 / fG2 ｜ ＞ 6.4 (2)
here,
nd _A , nC _A , nF _A , and ng _A are the refractive indices of the refractive optical element A with respect to the d-line, C-line, F-line, and g-line,
νd _A is the Abbe number (nd _A -1) / (nF _A -nC _A ) of the refractive optical element A,
θgF _A is a partial dispersion ratio (ng _A −nF _A ) / (nF _A −nC _A ) of the refractive optical element A,
fG1 is the focal length of the first lens group,
fG2 is the focal length of the second lens group,
It is. The imaging optical system according to claim 3, wherein the following conditional expression (5) is satisfied.
0.4 <θhg _A <1.2 (5)
here,
θhg _A is the partial dispersion ratio (nh _A −ng _A ) / (nF _A −nC _A ) of the h line of the refractive optical element A,
nh _A , nC _A , nF _A , and ng _A are the refractive indexes of the refractive optical element A with respect to the h-line, C-line, F-line, and g-line,
It is. The imaging optical system includes, in order from the object side to the image side, a first lens group having a positive refractive power, a second lens group having a negative refractive power, an aperture stop, and a third lens group having a positive refractive power. And a fourth lens group having a positive refractive power and a fifth lens group having a positive refractive power,
The distance between the first lens group and the second lens group is larger at the telephoto end than at the wide-angle end, the distance between the second lens group and the third lens group is small, and the third lens group and the third lens group are smaller. 5. The imaging optical system according to claim 3, wherein zooming is performed by changing an interval between adjacent lens groups so that an interval between the four lens groups is increased. In order from the object side to the image side, a first lens group having a positive refractive power, a second lens group having a negative refractive power, an aperture stop, a third lens group having a positive refractive power, and a positive refractive power A fourth lens group and a fifth lens group having a positive refractive power;
The distance between the first lens group and the second lens group is larger at the telephoto end than at the wide-angle end, the distance between the second lens group and the third lens group is small, and the third lens group and the third lens group are smaller. Zooming is performed by changing the distance between adjacent lens groups so that the distance between the four lens groups is increased, and the distance between the fourth lens group and the fifth lens group satisfies the following conditional expression (20): The imaging optical system according to any one of claims 3 to 5, wherein:
0 <TG ₄₅ / WG ₄₅ <5 (20)
here,
WG ₄₅ is the distance between the fourth lens group and the fifth lens group at the wide-angle end.
TG ₄₅ is the distance between the fourth lens group and the fifth lens group at the telephoto end.
It is. The imaging optical system according to any one of claims 3 to 6, comprising an optical element B and satisfying the following conditional expression (6).
| f _B / f _A |> 0.15 (6)
here,
f _A is the focal length of the refractive optical element A,
f _B is the focal length of the optical element B,
It is. The imaging optical system according to any one of claims 3 to 7, comprising an optical element B and satisfying the following conditional expression (7).
0 <θgF _B −θgF _BA <0.25 (7)
here,
nd _B , nC _B , nF _B , ng _B are the refractive indices of the optical element B with respect to the d-line, C-line, F-line, and g-line
νd _B is the Abbe number of the optical element B (nd _B -1) / (nF _B -nC _B ),
θgF _B is the partial dispersion ratio (ng _B −nF _B ) / (nF _B −nC _B ) of the optical element B,
θgF _BA is an effective partial dispersion ratio when the refractive optical element A and the optical element B are regarded as one optical element, and is expressed by the following equation:
θgF _BA = f _BA × ν _BA × (θgF _A × φ _A / νd _A + θgF _B × φ _B / νd _B ),
f _BA is the combined focal length of the optical element B and the refractive optical element A, and is represented by the following equation:
1 / f _BA = 1 / f _A + 1 / f _B ,
ν _BA is an Abbe number when the refractive optical element A and the optical element B are regarded as one optical element, and is represented by the following equation:
ν _BA = 1 / (f _BA × (φ _A / νd _A + φ _B / νd _B )),
φ _A is the refractive power of the refractive optical element A (φ _A = 1 / f _A ),
φ _B is the refractive power of the optical element B (φ _B = 1 / f _B ),
φ _BA is the combined refractive power of the optical element B and the refractive optical element A (φ _BA = 1 / f _BA ),
It is. The imaging optical system according to claim 3, wherein the following conditional expression (8) is satisfied.
1.0 <f _A /fG1<8.0 (8)
here,
f _A is the focal length of the refractive optical element A,
fG1 is the focal length of the first lens group,
It is. The imaging optical system according to any one of claims 3 to 9, wherein the following conditional expression (9) is satisfied.
−25 <(Ra + Rb) / (Ra−Rb) <− 2 (9)
here,
Ra is the radius of curvature of the refractive optical element A on the object side,
Rb is a radius of curvature on the image plane side of the refractive optical element A,
It is. In an electronic imaging apparatus having an imaging optical system and an imaging element,
The imaging optical system includes, in order from the object side to the image side, a first lens group having a positive refractive power, a second lens group having a negative refractive power, and an image side lens group having a positive refractive power. Having an interval between the first lens group and the second lens group during zooming,
A refractive optical element A having a positive refractive power is located in the first lens group,
An electronic imaging apparatus characterized by satisfying conditional formula (3-2) below.
0 <(Zb (3.3a) -Za (3.3a)) / (Zb (2.5a) -Za (2.5a)) <0.895 (3-2)
here,
fw is the focal length at the wide-angle end of the imaging optical system,
ft is the focal length at the telephoto end of the imaging optical system,
IH is the maximum image height on the image sensor of the imaging optical system,
Za (h) is the distance in the optical axis direction between the top of the object side surface on the optical axis of the refractive optical element A and the position at the height h on the object side,
Zb (h) is the distance in the optical axis direction between the top of the object side surface on the optical axis of the refractive optical element A and the position at the height h on the image plane side,
a is a value defined by the following equation (3-1):
a = {(IH) ² × log ₁₀ (ft / fw)} / fw (3-1)
It is. In an electronic imaging apparatus having an imaging optical system and an imaging element,
The imaging optical system according to any one of claims 3 to 10, wherein the imaging optical system satisfies the following conditional expression (3-2).
0 <(Zb (3.3a) -Za (3.3a)) / (Zb (2.5a) -Za (2.5a)) <0.895 (3-2)
here,
fw is the focal length at the wide-angle end of the imaging optical system,
ft is the focal length at the telephoto end of the imaging optical system,
IH is the maximum image height on the image sensor of the imaging optical system,
Za (h) is the distance in the optical axis direction between the top of the object side surface on the optical axis of the refractive optical element A and the position at the height h on the object side,
Zb (h) is the distance in the optical axis direction between the top of the object side surface on the optical axis of the refractive optical element A and the position at the height h on the image plane side,
a is a value defined by the following equation (3-1):
a = {(IH) ² × log ₁₀ (ft / fw)} / fw (3-1)
It is. The imaging optical system includes, in order from the object side to the image side, a first lens group having a positive refractive power, a second lens group having a negative refractive power, and an image side lens group having a positive refractive power. Having an interval between the first lens group and the second lens group during zooming,
A refractive optical element A having a positive refractive power is located in the first lens group,
The electronic imaging apparatus according to claim 11 or 12, wherein the following conditional expression (4-1), conditional expression (4-2), and conditional expression (2) are satisfied.
νd _A <30 (4-1)
0.54 <θgF _A <0.9 (4-2)
｜ G1 / G2 ｜ ＞ 6.4… （2）
here,
nd _A , nC _A , nF _A , and ng _A are the refractive indices of the refractive optical element A with respect to the d-line, C-line, F-line, and g-line,
νd _A is the Abbe number (nd _A -1) / (nF _A -nC _A ) of the refractive optical element A,
θgF _A is a partial dispersion ratio (ng _A −nF _A ) / (nF _A −nC _A ) of the refractive optical element A,
fG1 is the focal length of the first lens group,
fG2 is the focal length of the second lens group,
It is. The electronic imaging apparatus according to claim 1, wherein the following conditional expression (3-2) is satisfied.
0 <(Zb (3.3a) -Za (3.3a)) / (Zb (2.5a) -Za (2.5a)) <0.895 (3-2)
here,
fw is the focal length at the wide-angle end of the imaging optical system,
ft is the focal length at the telephoto end of the imaging optical system,
IH is the maximum image height on the image sensor of the imaging optical system,
Za (h) is the distance in the optical axis direction between the top of the object side surface on the optical axis of the refractive optical element A and the position at the height h on the object side,
Zb (h) is the distance in the optical axis direction between the top of the object side surface on the optical axis of the refractive optical element A and the position at the height h on the image plane side,
a is a value defined by the following equation (3-1):
a = {(IH) ² × log ₁₀ (ft / fw)} / fw (3-1)
It is. The following conditional expressions (10-1a), (10-1b), (10-1c), (10-2a), and (10-2b) are satisfied: The electronic imaging device according to any one of claims 11 to 14.
0.3 <Tngl (0) / Tbas (0) <3 (10-1a)
0.2 <Tnglt (0.7) / Tbast (0.7) <2.0 (10-1b)
0.1 <Tnglt (0.9) / Tbast (0.9) <1.4 (10-1c)
0.2 <(Tnglt (0.7) / Tbast (0.7)) / (Tngl (0) / Tbas (0)) <0.85 (10-2a)
0.10 <(Tnglt (0.9) / Tbast (0.9)) / (Tngl (0) / Tbas (0)) <0.75 (10-2b)
here,
Tngl (0) is the thickness on the axis of the refractive optical element A,
Tnglt (0.7) is the length that a light ray having a light height of 70% with respect to the maximum light height on the image sensor at the telephoto end passes through the refractive optical element A;
Tnglt (0.9) is the length that a light beam having a light height of 90% with respect to the maximum light beam height on the image sensor at the telephoto end passes through the refractive optical element A;
Tbas (0) is the thickness on the axis of the optical element B,
Tbast (0.7) is the length that a light beam having a light height of 70% with respect to the maximum light beam height on the image sensor at the telephoto end passes through the optical element B;
Tbast (0.9) is a length that a light beam having a light height of 90% with respect to the maximum light beam height on the image sensor at the telephoto end passes through the optical element B;
It is. The electronic imaging apparatus according to claim 1, wherein the following conditional expression (11a) or conditional expression (11b) is satisfied.
0.5 <(Tnglw (0.7) / (Tngl (0)) <0.95 (11a)
0.3 <(Tnglw (0.9) / (Tngl (0)) <0.85 (11b)
here,
Tngl (0) is the thickness on the axis of the refractive optical element A,
Tnglw (0.7) is a length that a light beam having a light height of 70% with respect to the maximum light beam height on the image sensor at the wide-angle end passes through the refractive optical element A;
Tnglw (0.9) is the length that a light beam having a light height of 90% with respect to the maximum light beam height on the image sensor at the wide-angle end passes through the refractive optical element A;
It is. The electronic imaging apparatus according to any one of claims 1, 2, 11 to 16, wherein the following conditional expression (12a) or conditional expression (12b) is satisfied.
0.5 <(Tnglt (0.7) / (Tngl (0)) <0.95 (12a)
0.3 <(Tnglt (0.9) / (Tngl (0)) <0.9 (12b)
here,
Tngl (0) is the thickness on the axis of the refractive optical element A,
Tnglt (0.7) is the length that a light ray having a light height of 70% with respect to the maximum light height on the image sensor at the telephoto end passes through the refractive optical element A;
Tnglt (0.9) is the length that a light beam having a light height of 90% with respect to the maximum light beam height on the image sensor at the telephoto end passes through the refractive optical element A;
It is. The following conditional expressions (13-1a), (13-1b), (13-1c), and (13-2) are satisfied: The electronic imaging device according to any one of the above.
0.3 <Tngl (0) / Tbas (0) <2.5 (13-1a)
0.15 <Tnglw (0.7) / Tbasw (0.7) <1.4 (13-1b)
0 <Tnglw (0.9) / Tbasw (0.9) <0.7 (13-1c)
0 <(Tnglw (0.9) / Tbasw (0.9)) / (Tngl (0) / Tbas (0)) <0.5 (13-2)
here,
Tngl (0) is the thickness on the axis of the refractive optical element A,
Tnglw (0.7) is a length that a light beam having a light height of 70% with respect to the maximum light beam height on the image sensor at the wide-angle end passes through the refractive optical element A;
Tnglw (0.9) is the length that a light beam having a light height of 90% with respect to the maximum light beam height on the image sensor at the wide-angle end passes through the refractive optical element A;
Tbas (0) is the thickness on the axis of the optical element B,
Tbasw (0.7) is the length of light passing through the optical element B at 70% of the maximum light height on the image sensor at the wide-angle end,
Tbasw (0.9) is the length that a light beam having a light height of 90% with respect to the maximum light beam height on the image sensor at the wide angle end passes through the optical element B;
It is.

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