JP5159941B2 - Zoom lens and imaging apparatus having the same - Google Patents

Description

  The present invention relates to a zoom lens and an image pickup apparatus having the same, and more particularly to a zoom lens used in an image pickup apparatus such as a digital camera, a video camera, and a film camera.

  A solid-state imaging device (photoelectric conversion device) used in an imaging apparatus such as a digital camera has been increased in the number of pixels. A zoom lens for an image pickup apparatus using a high-pixel image pickup element is required to have specifications for sufficiently correcting not only various monochromatic aberrations but also chromatic aberrations.

  In particular, a zoom lens with a high zoom ratio and a long focal length on the telephoto side is required to reduce the secondary spectrum in addition to the primary achromatism to correct chromatic aberration.

In order to correct chromatic aberration, an optical system using a liquid material exhibiting optical characteristics of high dispersion and abnormal partial dispersion has been proposed (Patent Document 1).
In addition, a zoom lens in which chromatic aberration on the telephoto side is improved using the dispersion characteristics of ITO resin using an optical element in which ITO fine particles are dispersed in resin has been proposed (Patent Document 2).

US Pat. No. 4,913,535 JP 2005-316047 A

  In an optical system using a liquid material having an achromatic action, a structure for sealing it is necessary, and the manufacturing tends to be complicated. In addition, there is a problem that it is difficult to maintain good environmental resistance because characteristics such as a refractive index and dispersion characteristics change due to temperature change.

  The present invention corrects chromatic aberration satisfactorily by disposing an optical element having appropriate dispersion characteristics at an appropriate position in an optical path, and an image pickup apparatus using the zoom lens having good optical performance over the entire zoom range. The purpose is to provide.

The zoom lens 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 a third lens group having a positive refractive power. In a zoom lens in which the interval between adjacent lens groups changes, when the Abbe number is νd and the partial dispersion ratio is θgF,
θgF − (− 1.665 × 10 ⁻⁷ · νd ³ + 5.213 × 10 ⁻⁵ · νd ² −5.656 × 10 ⁻³ · νd + 0.755)> 0
FGIT is the focal length when the third lens group has an optical element formed of a solid material that satisfies the following conditions, and the two refractive surfaces of the optical element are in contact with air, and the focal point of the entire system at the wide-angle end When the distance is fw,
3.1 ≦ fGIT / fw <15
It is characterized by satisfying the following conditions.

According to the present invention, it is possible to obtain a zoom lens that corrects chromatic aberration satisfactorily and has good optical performance over the entire zoom range, and an imaging apparatus using the zoom lens.

Lens cross-sectional view at the wide-angle end of Example 1 Various aberration diagrams at the wide-angle end of Example 1 Various aberration diagrams at the telephoto end of Example 1 Lens sectional view at the wide-angle end in Example 2 Various aberration diagrams at the wide-angle end of Example 2 Various aberration diagrams at the telephoto end of Example 2 Lens sectional view at the wide-angle end of Example 3 Various aberration diagrams at the wide-angle end of Example 3 Various aberration diagrams at the telephoto end of Example 3 Lens sectional view at the wide-angle end in Example 4 Various aberration diagrams at the wide-angle end of Example 4 Various aberration diagrams at the telephoto end of Example 4 Schematic diagram of main parts of an imaging apparatus of the present invention

  Embodiments of the zoom lens of the present invention and an image pickup apparatus having the same will be described below.

  FIG. 1 is a lens cross-sectional view at the wide angle end (short focal length end) of the zoom lens according to the first exemplary embodiment. 2 and 3 are aberration diagrams of the zoom lens of Example 1 at the wide-angle end and the telephoto end (long focal length end), respectively.

  FIG. 4 is a lens cross-sectional view at the wide-angle end of the zoom lens according to the second exemplary embodiment. FIGS. 5 and 6 are aberration diagrams of the zoom lens of Example 2 at the wide-angle end and the telephoto end, respectively.

  FIG. 7 is a lens cross-sectional view at the wide-angle end of the zoom lens according to the third exemplary embodiment. 8 and 9 are aberration diagrams of the zoom lens of Example 3 at the wide-angle end and the telephoto end, respectively.

  FIG. 10 is a lens cross-sectional view at the wide-angle end of the zoom lens according to the fourth exemplary embodiment. 11 and 12 are aberration diagrams of the zoom lens of Example 4 at the wide-angle end and the telephoto end, respectively.

  FIG. 13 is a schematic diagram of a main part of a camera (imaging device) including the zoom lens of the present invention.

  The zoom lens of each embodiment is a photographic lens system used in an imaging apparatus such as a video camera, a digital camera, or a silver salt film camera.

  In the lens cross-sectional view, the left side is the subject side (front), and the right side is the image side (rear). In the lens cross-sectional view, when i is the order of the lens group from the object side, Li indicates the i-th lens group. SP is an aperture stop. G is an optical block corresponding to an optical filter, a face plate, a quartz low-pass filter, an infrared cut filter, or the like.

  IP is the image plane. The image plane IP corresponds to an imaging plane of a solid-state imaging device (photoelectric conversion device) such as a CCD sensor or a CMOS sensor when a zoom lens is used as a photographing optical system of a video camera or a digital still camera. When a zoom lens is used as a photographing optical system for a silver salt film camera, it corresponds to a film surface.

  The arrows indicate the movement trajectory of each lens unit during zooming from the wide-angle end to the telephoto end and the movement trajectory during focusing.

  In the aberration diagrams, d and g are the d-line and g-line, respectively, and ΔM and ΔS are the meridional image surface and the sagittal image surface. Lateral chromatic aberration is represented by the g-line. ω is a half angle of view, and F is an F number.

  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 a range in which the mechanism can move on the optical axis.

  In each of the embodiments, in order from the object side to the image side, the zoom includes the first lens unit L1 having a positive refractive power, the second lens unit L2 having a negative refractive power, and the third lens unit L3 having a positive refractive power. It is a lens. During zooming, the distance between the lens groups changes. That is, the interval between adjacent lens groups changes. In each embodiment, a subsequent lens group is further provided on the image side of the third lens group L3. In the first and fourth embodiments, the subsequent lens unit includes a fourth lens unit L4 having a positive refractive power. In the second and third embodiments, the fourth lens unit L4 having a negative refractive power and the fifth lens unit L5 having a positive refractive power are formed in order from the object side to the image side. However, in the present invention, the subsequent lens group does not necessarily have to be provided, and it is sufficient if it is composed of at least three lens groups of positive, negative, and positive refractive power.

The third lens unit L3 has at least one optical element GIT formed of a solid material that satisfies the following conditions. That is, when the Abbe number of the solid material forming the optical element GIT is νd and the partial dispersion ratio is θgF,
θgF − (− 1.665 × 10 ⁻⁷ · νd ³ + 5.213 × 10 ⁻⁵ · νd ²
−5.656 × 10 ⁻³ · νd + 0.755)> 0
(1)
This solid material satisfies the following conditions.

  Here, when the refractive indexes of the materials for the wavelength 436 nm (g line), the wavelength 486 nm (F line), the wavelength 588 nm (d line), and the wavelength 656 nm (C line) are ng, nF, nd, and nC, respectively. The Abbe number νd and the partial dispersion ratio θgF are as follows.

νd = (nd−1) / (nF−nC)
θgF = (ng−nF) / (nF−nC)
Conditional expression (1) shows the wavelength dependence regarding the refractive index of the solid material used as the optical element GIT. The larger the positive value that the conditional expression (1) takes, the more effective the correction effect of the chromatic aberration of the material itself, which is preferable.

  If the conditional expression (1) is not satisfied, the correction effect of chromatic aberration is reduced, which is not good.

More preferably, while satisfying conditional expression (1), the partial dispersion ratio θgF is
θgF − (− 1.665 × 10 ⁻⁷ · νd ³ + 5.213 × 10 ⁻⁵ · νd ²
−5.656 × 10 ⁻³ · νd + 1.011) <0
(1a)
It is good to satisfy. According to this, it becomes easy to correct chromatic aberration without deteriorating other aberrations.

In order to further improve chromatic aberration, instead of the conditional expression (1), the partial dispersion ratio θgF is
θgF − (− 1.665 × 10 ⁻⁷ · νd ³ + 5.213 × 10 ⁻⁵ · νd ²
−5.656 × 10 ⁻³ · νd + 0.762) <0
(1b)
It is preferable to satisfy

Here, as a solid material constituting the optical element GIT, for example, there is a UV curable resin (nd = 1.636, νd = 22.7). In addition, TiO ₂ is dispersed in UV curable resin, N-polyvinylcarbazole (nd = 1.696, νd = 17.7), fluoropolymer (nd = 1.341, νd = 93.8), etc., which are host polymers. It is conceivable to use a material that has been removed.

The focal length of the optical element GIT is fGIT, the focal length at the wide-angle end of the entire system is fw, the focal length of the third lens unit L3 is f3, and the aperture stop SP at the telephoto end and the object side surface of the optical element GIT When the interval is t3,
3.1 ≦ fGIT / fw <15 (2)
0.8 <fGIT / f3 <8.0 (3)
0.5 <t3 / fw <4.0 (4)
Satisfies one or more of the following conditions. Here, the focal length of the optical element GIT is a focal length when the two refractive surfaces of the optical element GIT are both in contact with air (refractive index is 1).

  Thereby, the effect according to each condition is acquired.

  Conditional expression (2) relates to the refractive power of the optical element GIT in the air. When a material having anomalous dispersion represented by conditional expression (1) is used, the effect on chromatic aberration increases as the anomalous dispersion and refractive power of the material increase.

  If the lower limit of conditional expression (2) is exceeded, the curvature of the refracting surface becomes too large, making it difficult to correct spherical aberration and coma. On the other hand, if the upper limit is exceeded, the refractive power of the optical element GIT is too small, making it difficult to correct chromatic aberration on the telephoto side of the zoom lens.

  Conditional expression (3) relates to the refractive power of the optical element GIT, similar to conditional expression (2). In particular, it relates to the sharing of refractive power in the third lens L3 group. If the lower limit of conditional expression (3) is exceeded, the curvature of the refracting surface of the optical element GIT becomes too large, and it is difficult to correct spherical aberration and coma with the configuration of the third lens unit L3 having a small number of lenses. become.

  Conversely, when the upper limit is exceeded, the curvature of the refracting surface decreases, but when the optical element GIT is not in air but in contact with a material having a refractive index of 1 or more such as optical glass, the power of the refracting surface (refractive power, focal length The reciprocal) becomes small, and a sufficient chromatic aberration correction effect cannot be obtained.

  Conditional expression (4) relates to the arrangement of the optical element GIT in the optical system. By disposing the optical element GIT in the vicinity of the stop aperture having a low off-axis ray incident height so as to satisfy the conditional expression (4), it is easy to correct axial chromatic aberration without adversely affecting lateral chromatic aberration.

  In each embodiment, in order to further reduce aberration fluctuation during aberration correction and zooming, the numerical ranges of conditional expressions (2) to (4) are preferably set as follows.

3.1 ≦ fGIT / fw <10 (2a)
1.0 <fGIT / f3 <6.0 (3a)
0.8 <t3 / fw <3.5 (4a)
In each embodiment, the optical element GIT has two refractive surfaces in contact with the inorganic material.
This effectively corrects chromatic aberration.

  An optical element that satisfies the conditional expressions (1) and (2) may be provided in a lens group other than the third lens group L3 or in a plurality of lens groups. This makes it easier to correct chromatic aberration.

  In each embodiment, the third lens unit L3 includes two positive lenses and one negative lens. The third lens unit L3 has one or more aspheric surfaces. As a result, aberration fluctuations accompanying zooming are corrected satisfactorily.

  In each embodiment, part or all of the third lens unit L3 is moved so as to have a component in a direction perpendicular to the optical axis for image stabilization to correct image blur when the entire optical system vibrates. doing.

  As described above, in the zoom lens of each embodiment, an optical material different from existing optical glass and fluorite is applied. Then, by arranging the optical element made of this optical material at an appropriate position in the zoom lens with an appropriate refractive power, chromatic aberration is effectively corrected to obtain a high-quality image. In addition, a high-performance zoom lens that is easier to process than a conventional glass or fluorite having anomalous dispersion characteristics is easily obtained.

  Next, the lens configuration of each example will be described.

[Example 1]
The lens configuration of Example 1 in FIG. 1 will be described.

  In the lens cross-sectional view of FIG. 1, L1 is a first lens unit having a positive refractive power (optical power = reciprocal of focal length), L2 is a second lens unit having a negative refractive power, and L3 is a first lens unit having a positive refractive power. The third lens group, L4, is a fourth lens group having a positive refractive power.

  During zooming from the wide-angle end to the telephoto end, the first lens unit L1 moves along a locus convex toward the image side as indicated by an arrow. At this time, the first lens unit L1 moves so as to be positioned closer to the object side at the telephoto end than at the wide-angle end. The second lens unit L2 moves along a convex locus toward the image plane side, and corrects image plane fluctuations accompanying zooming. The third lens unit L3 moves to the object side. The fourth lens unit L4 moves along a locus convex toward the object side.

  In the first embodiment, a rear focus type is employed in which the fourth lens unit L4 is moved on the optical axis to perform focusing. When focusing from an infinitely distant object to a close object at the telephoto end, the fourth lens unit L4 is moved forward as indicated by an arrow 4c in the figure.

  A solid line curve 4a and a dotted line curve 4b relating to the fourth lens unit L4 respectively correct image plane fluctuations during zooming from the wide-angle end to the telephoto end when focusing on an object at infinity and an object at short distance. The movement locus for this is shown.

  For example, quick automatic focus adjustment is facilitated by moving the lightweight fourth lens unit L4 for focusing. The aperture stop SP moves together with the third lens unit L3 during zooming. Thereby, the number of groups divided by movement / movability is reduced, and the mechanical structure is simplified.

  Since the first lens unit L1 has a large effective lens diameter, it is preferable that the number of lenses is small. Therefore, the first lens unit L1 is constituted by a cemented lens or two independent lenses of a positive lens and a negative lens. Thereby, chromatic aberration generated in the first lens unit L1 is reduced.

  The second lens unit L2 includes three independent lenses, a negative meniscus lens having a convex surface on the object side, a negative lens having a biconcave shape, and a positive lens having a convex surface on the object side. This reduces aberration fluctuations during zooming, and particularly corrects distortion aberrations at the wide-angle end and spherical aberrations at the telephoto end.

  The third lens unit L3 includes, in order from the object side to the image side, two positive lenses, a positive lens, a positive lens, and a negative lens, and one negative lens. The third lens unit L3 has one or more aspheric surfaces. As a result, aberration fluctuations accompanying zooming are corrected satisfactorily.

  In order to satisfactorily correct the axial chromatic aberration on the telephoto side accompanying the increase in the zoom ratio, the space between the positive lens and the negative lens of the third lens unit L3 is filled with a solid material different from the standard optical glass. For example, a resin material (UV curable resin) that satisfies the conditional expressions (1) and (2) is made of a sandwich structure with optical glass, so that the environment resistance and reliability are improved as compared with an optical element having an exposed resin refractive surface. It is improving.

  The third lens unit L3 is moved so as to have a component perpendicular to the optical axis to correct image blur when the entire optical system vibrates.

  As a result, image stabilization is performed without newly adding an optical member such as a variable apex angle prism or a lens group for image stabilization, and the entire optical system is prevented from being enlarged.

[Example 2]
The lens configuration of Example 2 in FIG. 4 will be described.

  4, L1 is a first lens group having a positive refractive power, L2 is a second lens group having a negative refractive power, L3 is a third lens group having a positive refractive power, and L4 is a negative refractive power. The fourth lens unit L5 is a fifth lens unit having a positive refractive power.

  During zooming from the wide-angle end to the telephoto end, the second lens unit L2 moves to the image plane side as indicated by an arrow. The fifth lens unit L5 moves along a locus convex toward the object side. The fourth lens unit L4 moves along an S-shaped locus. The first lens unit L1 and the third lens unit L3 do not move for zooming. The fifth lens unit L5 corrects image plane fluctuations accompanying zooming and performs focusing.

  When focusing from an infinitely distant object to a close object at the telephoto end, the fifth lens unit L5 is moved to the object side as indicated by an arrow 5c.

  A solid line curve 5a and a dotted line curve 5b of the fifth lens unit L5 correct image plane variations caused by zooming from the wide-angle end to the telephoto end when focusing on an object at infinity and a short-distance object, respectively. The movement locus for this is shown.

  The first lens unit L1 is composed of one negative lens and two positive lenses. This effectively corrects chromatic aberration on the telephoto side.

  The second lens unit L2 includes, in order from the object side to the image side, a negative meniscus lens having a concave surface on the image surface side, a negative lens, a biconvex positive lens, and a negative lens.

  The third lens unit L3 is composed of two positive lenses and one negative lens. The same effect as in Example 1 is obtained by using the optical element GIT made of UV curable resin in the third lens unit L3.

  The fourth lens unit L4 is composed of one negative lens.

  The fifth lens unit L5 includes, in order from the object side to the image side, a biconvex positive lens, a biconvex positive lens, a negative lens, and a positive lens.

[Example 3]
The lens configuration of Example 3 in FIG. 7 will be described. The zoom lens according to the third exemplary embodiment includes five lens groups having the same refractive power arrangement as that of the second exemplary embodiment illustrated in FIG.

  During zooming from the wide-angle end to the telephoto end, the second lens unit L2 and the fourth lens unit L4 move toward the image side, and the third lens unit L3 moves along a convex locus toward the object side. The fifth lens unit L5 moves along an S-shaped locus.

  The lens configuration of the first lens unit L1 is the same as that of the second embodiment. The lens configuration of the second lens unit L2 is the same as that of the first embodiment.

The third lens unit L3 includes a positive lens, a negative lens, and a positive lens in order from the object side to the image side. Then, chromatic aberration is effectively corrected using an optical element GIT made of a TiO ₂ fine particle dispersed material.

  The fourth lens unit L4 includes one negative lens. The fifth lens unit L5 includes a cemented lens of a positive lens and a negative lens.

  A rear focus type is employed in which focusing is performed by moving the fifth lens unit L5 on the optical axis.

  When focusing from an infinitely distant object to a close object at the telephoto end, the fifth lens unit L5 is extended forward as indicated by an arrow 5c in the figure. A solid curve 5a and a dotted curve 5b relating to the fifth lens unit L5 are for correcting image plane fluctuations during zooming from the wide-angle end to the telephoto end when focusing on an object at infinity and a short-distance object, respectively. The movement trajectory is shown.

[Example 4]
The lens configuration of Example 4 in FIG. 10 will be described. The zoom lens of Example 4 is composed of four lens groups having the same refractive power arrangement as that of Example 1 of FIG.

  During zooming from the wide-angle end to the telephoto end, the first lens unit L1 moves along a locus convex toward the image side as indicated by an arrow. At this time, the first lens unit L1 moves so as to be positioned closer to the object side at the telephoto end than at the wide-angle end.

  The second lens unit L2 moves to the image side. The third and fourth lens groups L3 and L4 move along a locus convex toward the object side.

  In the fourth embodiment, as in the first embodiment, a rear focus type in which focusing is performed by moving the fourth lens unit L4 on the optical axis is employed.

  The technical meanings of the arrows 4a, 4b, and 4c regarding the fourth lens unit L4 are the same as those in the first embodiment.

  The aperture stop SP moves to the object side independently of the third lens unit L3 during zooming from the wide-angle end to the telephoto end. Moving the aperture stop SP separately from the third lens unit L3 is advantageous for reducing the front lens diameter. Further, the aperture stop SP may be fixed. In this case, since it is not necessary to move the aperture unit, the driving torque of the actuator to be driven can be set small during zooming, which is advantageous in terms of power saving.

  The first lens unit L1 includes three lenses, a cemented lens of a negative lens and a positive lens, and a positive lens. As a result, chromatic aberration occurring in the first lens unit L1 is reduced.

  The lens configuration of the second lens unit L2 is the same as that of the first embodiment.

  The third lens unit L3 includes two positive lenses, a positive lens, a negative lens, and a positive lens, and one negative lens in order from the object side to the image side.

The third lens unit L3 effectively corrects chromatic aberration using an optical element GIT made of a TiO ₂ fine particle dispersed material. The rest is the same as in the first embodiment.

  Hereinafter, specific numerical data of Numerical Examples 1 to 4 will be shown. In each numerical example, i indicates the number of the surface counted from the object side. ri is the radius of curvature of the i-th optical surface (i-th surface). di is an axial distance between the i-th surface and the (i + 1) -th surface. ni and νi are the refractive index and Abbe number of the material of the i-th optical member with respect to the d-line, respectively. f is a focal length, F is an F number, and ω is a half angle of view.

  Further, the aspherical shape is such that X is the amount of displacement from the surface vertex in the optical axis direction, h is the height from the optical axis in the direction perpendicular to the optical axis, R is the paraxial radius of curvature, k is the conic constant, When C, D, E... Are the aspheric coefficients of the respective orders,

Represented by

Note that “E ± XX” in each aspheric coefficient means “× 10 ^{± XX} ”.

  The plane closest to the image side (surface having a radius of curvature ∞) in each embodiment is a surface constituting the optical block G.

  Table 1 shows the relationship between the conditional expressions described above and the numerical values in the numerical examples. The refractive index with respect to the d, g, C, and F-line spectra of the material of the optical element GIT used in each example is also shown in Table 1.

Aspherical coefficient 12th surface k = -1.71740 B = 1.64017E-4 C = 8.02840E-7 D = 1.88795E-8
13th surface k = -1.65387E-1 B = 1.79023E-4 C = -1.56975E-6 D = 1.04720E-7

20th surface of aspheric coefficient k = -7.82015 B = -1.93647E-5 C = 2.08784E-7 D = -2.36483E-9
28th surface k = -1.58559 B = 6.33790E-5 C = -6.19819E-8 D = -3.59058E-10

Aspherical coefficient 14th surface k = -1.69741E2 B = -1.57759E-4 C = 1.38087E-5 D = -3.93944E-7

Aspherical coefficient 13th surface k = -8.63724E-1 B = 1.36448E-4 C = 3.78036E-5 D = 5.47074E-7
E = -1.88292E-9 A '=-8.59213E-5 B' =-1.01902E-4 C '=-6.93498E-6

  Next, an embodiment of a digital still camera using a zoom lens as shown in each embodiment as a photographing optical system will be described with reference to FIG.

  In FIG. 13, reference numeral 20 denotes a camera body. Reference numeral 21 denotes a photographing optical system constituted by any one of the zoom lenses described in the first to fourth embodiments. Reference numeral 22 denotes a solid-state imaging device (photoelectric conversion device) such as a CCD sensor or a CMOS sensor that receives a subject image formed by the photographing optical system 21 and is built in the camera body.

  A memory 23 records information corresponding to a subject image photoelectrically converted by the solid-state imaging device 22. Reference numeral 24 denotes a finder for observing a subject image formed on the solid-state image sensor 22, which includes a liquid crystal display panel or the like.

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

L1 1st lens group L2 2nd lens group L3 3rd lens group L4 4th lens group L5 5th lens group SP Aperture stop IP Image surface G Glass block such as CCD force plate and low-pass filter d d line g g line ΔM Meridional image plane ΔS Sagittal image plane

Claims (6)

In order from the object side to the image side, there are a first lens group having a positive refractive power, a second lens group having a negative refractive power, and a third lens group having a positive refractive power. In a changing zoom lens, when the Abbe number is νd and the partial dispersion ratio is θgF,
θgF − (− 1.665 × 10 ⁻⁷ · νd ³ + 5.213 × 10 ⁻⁵ · νd ² −5.656 × 10 ⁻³ · νd + 0.755)> 0
FGIT is the focal length when the third lens group has an optical element formed of a solid material that satisfies the following conditions, and the two refractive surfaces of the optical element are in contact with air, and the focal point of the entire system at the wide-angle end When the distance is fw,
3.1 ≦ fGIT / fw <15
A zoom lens characterized by satisfying the following conditions: When the focal length of the third lens group is f3,
0.8 <fGIT / f3 <8.0
The zoom lens according to claim 1, wherein the following condition is satisfied. When having an aperture stop, and when the distance between the aperture stop at the telephoto end and the object side surface of the optical element is t3,
0.5 <t3 / fw <4.0
The zoom lens according to claim 1 or 2, wherein the following condition is satisfied. The zoom lens includes, in order from the object side to the image side, the first lens group, the second lens group, the third lens group, and a fourth lens group having a positive refractive power. Item 4. The zoom lens according to any one of Items 1 to 3. The zoom lens according to claim 1, wherein an image is formed on the photoelectric conversion element. An imaging apparatus comprising: the zoom lens according to claim 1; and a photoelectric conversion element that receives an image formed by the zoom lens.