JP2014089385A - Zoom lens and optical device having the same - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a zoom lens which offers a high zoom ratio, is well corrected for various aberrations and particularly well for chromatic aberration over an entire zoom range, and provides superior optical performance over the entire zoom range.SOLUTION: The zoom lens includes a first lens group which has positive refractive power and is located on the most object side, a plurality of lens groups which have negative refractive power and are located on the image side relative to the first lens group, an aperture stop, a lens group LA which has positive refractive power and is located on the image side relative to a lens group LN which is one of the plurality of lens groups having negative refractive power and is located on the most object side, and a lens group LB which has positive or negative refractive power and is located on the image side relative to the lens group LA and the aperture stop. When zooming from the wide angle end to the telephoto end, distance between the lens group LA and the lens group LB widens and distance between the aperture stop and the lens group LB widens. The lens group LA has one or more diffraction optical elements. Power φof the entire system at the wide angle end, power φof the entire system at the telephoto end, a chromatic aberration correction capability SUM(A) of the lens group LA, and a chromatic aberration correction capability SUM(B) of the lens group LB are each set appropriately.

Description

  The present invention relates to a zoom lens and an optical apparatus having the same, and is particularly suitable for a digital camera, a video camera, a TV camera, a surveillance camera, a silver salt photography camera, a projector, and the like.

  In recent years, a photographing optical system used in an imaging apparatus such as a digital camera or a video camera or a projection optical system used in a projector is required to be a zoom lens having a high zoom ratio and a high optical performance over the entire zoom range. .

  As a zoom lens that can easily achieve a high zoom ratio, a positive lead type zoom lens is known in which the lens unit closest to the object side is a lens unit having a positive refractive power. As a zoom lens in which the entire optical system can be easily reduced, a zoom lens using a so-called inner focus method or rear focus method in which the second lens unit and subsequent lens units are moved in the optical axis direction for focusing is known. . A zoom lens having a high zoom ratio and a small zoom lens system using a rear lead method with a positive lead type is known (Patent Document 1).

  In Patent Document 1, the first, third, and fifth lenses in a six-group zoom lens including first to sixth lens units having positive, negative, positive, negative, positive, and negative refractive powers in order from the object side to the image side. The zooming is performed by moving the sixth lens group. A zoom lens in which focusing is performed by moving the fourth and fifth lens groups is disclosed. In Patent Document 1, an aperture stop is disposed between the third lens group and the fourth lens group. In Patent Document 1, anomalous dispersion material is used for the positive lens material of the first lens group and the third lens group, and various aberrations including chromatic aberration are corrected well without increasing the entire lens diameter.

  In general, in order to obtain high optical performance over the entire zoom range in a zoom lens, it is important to correct chromatic aberration well in addition to correction of monochromatic (short wavelength) aberrations such as field curvature and astigmatism. .

  In a positive lead type zoom lens, there is known a zoom lens in which a diffractive optical element is arranged in an optical system to correct chromatic aberration to improve performance (Patent Documents 2 and 3). In Patent Document 2, in order from the object side to the image side, each lens group interval is set in a seven-group zoom lens including first to seventh lens groups having positive, negative, positive, negative, positive, negative, and positive refractive powers. In this case, zooming is performed and a diffractive optical element is used for the first lens group. A zoom lens in which focusing is performed by the sixth lens group is disclosed.

  In Patent Document 3, in order from the object side to the image side, in a six-group zoom lens composed of lens units having positive, negative, positive, positive, negative, and positive refractive power, zooming is performed by changing the distance between the lens groups. A zoom lens using a diffractive optical element in the third lens group close to the zoom lens is disclosed.

JP 2004-212612 A JP 2004-317867 A JP 2001-356271 A

  In recent years, zoom lenses have higher image quality, such as that represented by Super Hi-Vision (pixel number 8000 × 4000, pixel size around 1 μm), which is higher than the image quality equivalent to full high-definition (pixel number 1920 × 1080, pixel size number μm). It is desired that an image of

  In order to obtain high optical performance over the entire zoom range while achieving a high zoom ratio in the zoom lens, it is important to particularly reduce chromatic aberration in addition to various aberrations such as field curvature and astigmatism. When a diffractive optical element is used as a part of the zoom lens, it becomes easy to correct chromatic aberration, and accordingly, other aberrations can be easily corrected, and a zoom lens having high optical performance over the entire zoom range with a high zoom ratio. Easy to get.

  However, even if a diffractive optical element is simply provided in the lens system, it is difficult to obtain a zoom lens having high optical performance with good correction of chromatic aberration unless the position, power, and lens configuration of the lens group including the diffractive optical element are appropriately set. . In addition, it is necessary to appropriately set the zoom type, the power of each lens group, the lens configuration of each lens group, and the like. If these lens configurations are not appropriate, it will be difficult to obtain a high-performance zoom lens over the entire zoom range even if a diffractive optical element is used.

  An object of the present invention is to provide a zoom lens having a high zoom ratio, excellently correcting various aberrations, particularly chromatic aberration, over the entire zoom range, and having high optical performance in the entire zoom range, and an optical apparatus having the same.

The zoom lens according to the present invention includes a first lens group having a positive refractive power closest to the object side, a plurality of lens groups having a negative refractive power closer to the image side than the first lens group, an aperture stop, and the plurality of the plurality of lens groups. A lens unit LA having a positive refractive power on the image side relative to the lens unit LN located closest to the object side among the lens units having a negative refractive power, and positive or negative on the image side relative to the lens group LA and the aperture stop. A zoom lens having a lens unit LB having a refractive power and having a wide interval between the lens unit LA and the lens unit LB during zooming from the wide-angle end to the telephoto end, and a wide interval between the aperture stop and the lens unit LB. The lens group LA has one or more diffractive optical elements, and the total system power at the wide-angle end is φ _w , the total system power at the telephoto end is φ _t , and the chromatic aberration correction power of the lens group LA is SUM. (A), the chromatic aberration correction power of the lens unit LB is SUM (B) And when
-1.0 × 10 ^-3 <SUM (A) × SUM (B) / (φ _w × φ _t ) <-1.0 × 10 ^-6
0.1 <│SUM (A) / SUM (B) │ <6.0
It satisfies the following conditional expression.

  According to the present invention, it is possible to obtain a zoom lens having a high zoom ratio and excellent correction of various aberrations, particularly chromatic aberration, over the entire zoom range and having high optical performance in the entire zoom range.

(A), (B) Cross-sectional views of the zoom lens of Example 1 at the wide-angle end and the telephoto end when the object distance is infinite. (A), (B), (C) Longitudinal aberration diagrams of the zoom lens of Example 1 at the wide-angle end, the intermediate zoom position, and the telephoto end when the object distance is infinite. (A), (B) Cross-sectional views of the zoom lens of Example 2 at the wide-angle end and the telephoto end when the object distance is infinite. (A), (B), (C) Longitudinal aberration diagrams at the wide-angle end, the intermediate zoom position, and the telephoto end when the object distance of the zoom lens of Example 2 is infinite. (A), (B) Cross-sectional views of the zoom lens of Embodiment 3 at the wide-angle end and the telephoto end when the object distance is infinite. (A), (B), (C) Longitudinal aberration diagrams at the wide-angle end, the intermediate zoom position, and the telephoto end of the zoom lens of Example 3 at an object distance of infinity. (A), (B) Cross-sectional views of the zoom lens of Example 4 at the wide-angle end and the telephoto end when the object distance is infinite. (A), (B), (C) Longitudinal aberration diagrams at the wide-angle end, the intermediate zoom position, and the telephoto end of the zoom lens of Example 4 at an object distance of infinity. (A), (B) Cross-sectional views of the zoom lens of Example 5 at the wide-angle end and the telephoto end when the object distance is infinite. (A), (B), (C) Longitudinal aberration diagrams at the wide-angle end, the intermediate zoom position, and the telephoto end of the zoom lens of Example 5 at an infinite object distance (A), (B) Cross-sectional views of the zoom lens of Example 6 at the wide-angle end and the telephoto end when the object distance is infinite. (A), (B), (C) Longitudinal aberration diagrams at the wide-angle end, the intermediate zoom position, and the telephoto end of the zoom lens of Example 6 at an infinite object distance Explanatory drawing when the present invention is applied to an imaging apparatus Explanatory drawing when the present invention is applied to a projection apparatus Explanatory drawing of the optical arrangement of the zoom lens of the present invention

  Hereinafter, preferred embodiments of the present invention will be described in detail with reference to the accompanying drawings. 1, FIG. 3, FIG. 5, FIG. 7, FIG. 9, and FIG. 11 are lens cross-sectional views of Examples 1 to 6 of the zoom lens of the present invention, respectively. In the lens cross-sectional view, (A) is a lens cross-sectional view at the wide-angle end, and (B) is a lens cross-sectional view at the telephoto end. 2, 4, 6, 8, 10, and 12 are longitudinal aberration diagrams of Examples 1 to 6 of the zoom lens according to the present invention, respectively. In the longitudinal aberration diagram, (A) is a longitudinal aberration diagram at the wide-angle end, (B) is a longitudinal aberration diagram at the zoom intermediate position, and (C) is a longitudinal aberration diagram at the telephoto end.

  In each lens cross-sectional view, L0 is a zoom lens. SP is an aperture stop. L1 is a first lens group, L2 is a second lens group, and L3 is a third lens group. L4 is a fourth lens group, L5 is a fifth lens group, L6 is a sixth lens group, L7 is a seventh lens group, and L8 is an eighth lens group. LN is a lens unit having negative refractive power closest to the object side of the zoom lens, LA is a lens group having positive refractive power, and LB is a lens group having positive or negative refractive power.

IP is an image plane, and when applied to a video camera or a digital camera, an imaging plane of a solid-state imaging device (photoelectric conversion device) such as a CCD sensor or a CMOS sensor that receives an image is applied to a silver salt film camera. In some cases, it corresponds to the film surface. Further, when applied to an image projection apparatus such as a projector, it corresponds to an image display element such as a liquid crystal panel. DOE is a diffractive optical element. D is a diffractive optical part (diffractive optical surface) constituting a part of the diffractive optical element DOE. Of the diffracted light generated from the diffractive optical part D, the diffraction order m of the diffracted light used in each embodiment is 1, and the design wavelength λ ₀ is the wavelength of the d-line (587.56 nm).

  The arrows indicate the movement trajectory of each lens unit during zooming from the wide-angle end to the telephoto end. Arrows related to focusing and floating indicate the moving direction of each lens group when focusing from an object at infinity to a near object.

The zoom lens of the present invention includes a first lens unit L1 having a positive refractive power closest to the object side,
A plurality of lens units having negative refractive power and an aperture stop SP are provided on the image side of the first lens unit L1. Further, among the plurality of lens units having negative refractive power, the lens unit LA having positive refractive power on the image side relative to the lens unit LN located closest to the object side, and positive or closer to the image side than the lens group LA and the aperture stop SP. The lens unit LB has a negative refractive power. During zooming from the wide-angle end to the telephoto end, the distance between the lens unit LA and the lens unit LB is increased, and the lens unit is moved so that the interval between the aperture stop SP and the lens unit LB is increased.

  In Example 1 of FIG. 1, in order from the object side to the image side, a first lens unit L1 having a positive refractive power, a second lens unit L2 having a negative refractive power, a third lens unit L3 having a positive refractive power, and a negative lens unit. The lens unit includes a fourth lens unit L4 having a refractive power, a fifth lens unit L5 having a positive refractive power, and a sixth lens unit L6 having a negative refractive power. During zooming, the second lens unit L2 does not move, and the other lens units move.

  In Example 2 of FIG. 3, in order from the object side to the image side, the first lens unit L1 having a positive refractive power, the second lens unit L2 having a negative refractive power, the third lens unit L3 having a positive refractive power, and a negative lens unit. The lens unit includes a fourth lens unit L4 having a refractive power, a fifth lens unit L5 having a positive refractive power, and a sixth lens unit L6 having a negative refractive power. During zooming, the third lens unit L3 does not move, and the other lens units move.

  In Example 3 of FIG. 5, in order from the object side to the image side, the first lens unit L1 having a positive refractive power, the second lens unit L2 having a negative refractive power, the third lens unit L3 having a positive refractive power, and a positive lens unit. A fourth lens unit L4 having refractive power and a fifth lens unit L5 having negative refractive power are included. Furthermore, it has a sixth lens unit L6 having a positive refractive power and a seventh lens unit L7 having a negative refractive power. During zooming, the second lens unit L2 and the fifth lens unit L5 do not move, and the other lens units move.

  In Example 4 of FIG. 7, in order from the object side to the image side, the first lens unit L1 having a positive refractive power, the second lens unit L2 having a negative refractive power, the third lens unit L3 having a negative refractive power, and a positive lens unit. A fourth lens unit L4 having refractive power and a fifth lens unit L5 having negative refractive power are included. Furthermore, it has a sixth lens unit L6 having a positive refractive power and a seventh lens unit L7 having a negative refractive power. During zooming, the third lens unit L3 does not move, and the other lens units move.

  In Example 5 of FIG. 9, in order from the object side to the image side, a first lens unit L1 having a positive refractive power, a second lens unit L2 having a negative refractive power, a third lens unit L3 having a positive refractive power, and a positive lens unit. A fourth lens unit L4 having refractive power and a fifth lens unit L5 having negative refractive power are included. Furthermore, it has a sixth lens unit L6 having a positive refractive power and a seventh lens unit L7 having a negative refractive power. During zooming, the second lens unit L2 does not move, and the other lens units move.

  In Example 6 of FIG. 11, in order from the object side to the image side, a first lens unit L1 having a positive refractive power, a second lens unit L2 having a positive refractive power, a third lens unit L3 having a negative refractive power, and a positive lens unit. A fourth lens unit L4 having refractive power and a fifth lens unit L5 having negative refractive power are included. Furthermore, it has a sixth lens unit L6 having a positive refractive power, a seventh lens unit L7 having a negative refractive power, and an eighth lens unit L8 having a positive refractive power. During zooming, the third lens unit L3, the sixth lens unit L6, and the eighth lens unit L8 do not move, and the other lens units move.

  In the aberration diagram, d and g are d line and g line in this order. M and S are a meridional image surface and a sagittal image surface. Fno is an F number, and ω is a half angle of view (degrees). In the aberration diagrams, spherical aberration is drawn at a scale of 0.4 mm, astigmatism is drawn at 0.4 mm, distortion is 2%, and lateral chromatic aberration is drawn at a scale of 0.05 mm. In each of the following embodiments, the wide-angle end and the telephoto end refer to zoom positions when the moving lens groups are positioned at both ends of a range in which the mechanism can move on the optical axis.

In each embodiment, the lens unit LA has one or more diffractive optical elements. The total system power at the wide-angle end is φ _w , the total system power at the telephoto end is φ _t , the chromatic aberration correction power of the lens group LA is SUM (A), and the chromatic aberration correction power of the lens group LB is SUM (B). At this time,
-1.0 × 10 ^-3 <SUM (A) × SUM (B) / (φ _w × φ _t ) <-1.0 × 10 ^-6 (1)
0.1 <│SUM (A) / SUM (B) │ <6.0 (2)
The following conditional expression is satisfied.

  Here, in each embodiment, the chromatic aberration correcting power of the lens unit LA is expressed as SUM (A), and the chromatic aberration correcting power of the lens unit LB is expressed as SUM (B).

The partial dispersion ratio difference and Abbe number of each lens constituting the lens group LA are Δθ _gFAi and ν _Ai , and the power of each lens is φ _Ai , where i is a lens number given in order from the object side in the lens group LA. ). The partial dispersion ratio difference and the Abbe number of each lens constituting the lens group LB are Δθ _gFBj and ν _Bj , the power of each lens is φ _Bj , and j is a lens number given in order from the object side in the lens group LB. ). At this time, the chromatic aberration correction forces SUM (A) and SUM (B) are defined as follows.

However, the Abbe numbers ν _Ai , ν _Bj , partial dispersion ratios θ _gFAi , θ _gFBj , partial dispersion ratio differences Δθ _gFAi , Δθ _gFBj are the refractive indexes of the materials constituting each lens at the d line, N _dAi , N _dBj , g line _Let N _gAi and N _{gBj be} the refractive indices at. Further, if the refractive index in the C line is N _CAi and N _CBj , and the refractive index in the F line is N _FAi and N _FBj , the following formula is used.

_{ν Ai = (N dAi -1)} / (N FAi -N CAi)
ν _Bj = (N _dBj −1) / (N _FBj −N _CBj )
_{θ gFAi = (N gAi -N FAi} ) / (N FAi -N CAi)
θ _gFBj = (N _gBj −N _FBj ) / (N _FBj −N _CBj )
Δθ _gFAi = θ _gFAi − (− 1.61783 × 10 ⁻³ × ν _Ai +0.64146)
Δθ _gFBj = θ _gFBj − (− 1.61783 × 10 ⁻³ × ν _Bj +0.64146)
The zoom lens of the present invention is based on the following idea.

  As a zoom lens used for conventional imaging or image projection, a zoom lens as shown in the first prior art document is known. These zoom lenses have lens groups having positive, negative, positive, negative, positive, and negative refractive powers in order from the object side to the image side. In the zoom lens having such a configuration, in order to improve the image quality without increasing the size of the lens system, mainly correction of chromatic aberration, curvature of field, astigmatism and the like are favorably performed. It is necessary to correct.

  In general, aberration correction in a zoom lens requires aberration correction at the wide-angle end and the telephoto end and aberration correction at an intermediate zoom position therebetween.

  When a zoom lens of a multi-lens group movement type is designed with priority given to zoom efficiency, each lens group is appropriately subjected to variable magnification, and the lens group with appropriate power (refractive power) is moved. As a result, the same zoom ratio can be obtained with a shorter movement amount than when only one zoom lens group is moved. For this reason, downsizing of the entire zoom lens system can be achieved. If the size of the entire zoom lens system and the amount of movement of each lens group are not reduced, a higher zoom ratio can be easily achieved.

  However, when high image quality as represented by Super Hi-Vision is assumed, the image forming performance (including flare) of the conventional zoom lens is not sufficient, and further higher performance is required.

  Many conventional zoom lenses retain chromatic aberration, curvature of field, and astigmatism, which greatly affects the imaging performance. For this reason, it has been difficult for a conventional zoom lens to resolve a high spatial frequency over the entire zoom range. If a diffractive optical element is used for the first lens group as in the prior art, there is an effect of reducing chromatic aberration. come.

  If the objective is simply to reduce aberrations, the power of each lens group can be relaxed and the amount of movement of the variable power lens group can be increased. However, this method increases the stroke amount (movement amount) of the variable power lens group, which increases the size of the entire zoom lens system.

  The present invention makes it possible to correct aberrations while suppressing the increase in size of the entire system, and to suppress the flare generated from the diffractive optical element, and to achieve high optical performance over the entire zoom range. The method is specified.

  Next, features of the zoom lens of each embodiment will be described. The zoom lens L0 of each embodiment has the first lens unit L1 having a positive refractive power on the most object side. A plurality of lens units having negative refractive power and an aperture stop SP are provided at arbitrary positions on the image side of the first lens unit L1. Among the plurality of lens groups having negative refractive power, the lens group LA having positive refractive power is provided on the image side of the lens group LN located closest to the object side. The lens group LA has at least one diffractive optical element DOE.

  The lens unit LB has a positive or negative refractive power at a position closer to the image side than the lens unit LA and the aperture stop SP. During zooming, the distance between the lens unit LA and the lens unit LB is wider at the telephoto end than at the wide-angle end, and the distance between the aperture stop SP and the lens unit LB is widened. Furthermore, the zoom lens of the present invention satisfies the conditional expressions (1) and (2).

  Next, the lens configuration of the zoom lens according to the present invention and the movement of each lens group during zooming will be described with reference to FIG. The reference numerals assigned to the members in FIGS. 15A and 15B are the same as those attached to the members in the lens cross-sectional view. FIG. 15A shows the paraxial refractive power arrangement at the wide-angle end, and FIG. 15B shows the paraxial refractive power arrangement at the telephoto end. The subsequent group is a generic term for the lens groups after the lens group LB.

  In a zoom lens having a lens unit having a positive refractive power on the most object side, the first problem is correction of axial chromatic aberration at the telephoto end. In order to effectively correct this, the diffractive optical element DOE may be disposed in the first lens unit L1 in which the axial paraxial ray passes through a high position from the optical axis.

  However, flare caused by unnecessary diffracted light cannot be ignored. Therefore, in the present invention, in order to avoid this flare, the diffractive optical element DOE is disposed in the lens group LA on the image side with respect to the first lens group L1. By disposing the diffractive optical element DOE on the image side of the first lens unit L1 and in the vicinity of the aperture stop SP in this way, as shown in FIG. It becomes difficult to hit DOE. And it becomes easy to correct axial chromatic aberration at the telephoto end while reducing flare.

  At this time, when the axial chromatic aberration is corrected by the diffractive optical element DOE near the aperture stop SP at the telephoto end, the height of the axial paraxial light beam passing through the diffractive optical element DOE from the optical axis is the first lens group. Lower than that passing through L1. For this reason, it is necessary to make the power of the diffractive optical element DOE relatively larger than when the diffractive optical element DOE is arranged in the first lens unit L1.

  Further, when looking at the positional relationship of each lens group at the wide angle end, as shown in FIG. 15 (A), the height from the optical axis of the axial paraxial ray passing through the lens group LA is as follows. Among them, it passes through a high position. As a result, axial chromatic aberration that can be corrected well at the telephoto end becomes excessively corrected at the wide-angle end.

  Therefore, in order to reversely correct the axial chromatic aberration that has been overcorrected, a lens unit LB having an appropriate chromatic aberration correcting power is disposed on the image side of the lens unit LA and the aperture stop SP, and at the wide angle end. Axial chromatic aberration is reduced. In zooming, the distance between the lens unit LA and the lens unit LB and the distance between the lens unit LB and the aperture stop SP are arranged to be farther (wider) at the telephoto end than at the wide-angle end.

  By disposing the lens unit LB away from the aperture stop SP in this way, the axial paraxial ray passing through the lens unit LB is low from the optical axis and the pupil paraxial ray is high from the optical axis at the telephoto end. It can be configured to pass through. By doing so, the lens unit LB can easily correct the lateral chromatic aberration without significantly affecting the axial chromatic aberration correction. Then, by disposing the lens unit LB away from the lens unit LA, the axial chromatic aberration correction at the telephoto end is effectively performed by the lens unit LA.

  Next, the technical meaning of each conditional expression described above will be described. Conditional expression (1) relates to the magnitude of the chromatic aberration correction power of the lens group LA and the lens group LB. When the upper limit value of conditional expression (1) is exceeded, the chromatic aberration correcting power of the lens group LA and the lens group LB is biased too weakly or both are too weak. Then, axial chromatic aberration remains particularly at the telephoto end.

On the other hand, when the lower limit value of conditional expression (1) is exceeded, the chromatic aberration correcting powers of the lens unit LA and the lens unit LB are biased too much, or both become too strong. In this case, axial chromatic aberration is excessively corrected particularly at the telephoto end, and it becomes difficult to correct chromatic aberration in the entire system. The numerical range of conditional expression (1) is more preferably set as follows.
-5.0 × 10 ^-4 <SUM (A) × SUM (B) / (φ _w × φ _t ) <-4.0 × 10 ^-6 (1a)
The numerical range of conditional expression (1a) is more preferably set as follows.
-1.0 × 10 ^-4 <SUM (A) × SUM (B) / (φ _w × φ _t ) <-5.0 × 10 ^-6 (1b)

  Conditional expression (2) relates to the balance of chromatic aberration correction power of the lens unit LA and the lens unit LB. When the upper limit value or lower limit value of conditional expression (2) is exceeded, the chromatic aberration correcting power of the lens unit LA becomes too large or too small than that of the lens unit LB. Then, it becomes difficult to correct axial chromatic aberration in a balanced manner at the wide angle end and the telephoto end, and axial chromatic aberration remains at either the wide angle end or the telephoto end.

The numerical range of conditional expression (2) is more preferably set as follows.
0.2 <│SUM (A) / SUM (B) │ <5.0 (2a)
The numerical range of conditional expression (2a) is more preferably set as follows.
0.5 <│SUM (A) / SUM (B) │ <4.0 (2b)

As described above, according to each embodiment, it is possible to obtain a zoom lens having a small overall size and high image quality while simultaneously reducing chromatic aberration, curvature of field, and astigmatism in the entire zoom region.
With the configuration as described above, the zoom lens according to the present invention can be achieved, but it is more preferable that at least one of the following conditions is satisfied. A zoom lens having the above can be easily obtained.

Of the lens group LA and the aperture stop SP at the wide angle end, the distance from the most object-side surface vertex of the element located closest to the object side to the most image-side surface vertex of the lens group LB is _defined as d _LS . Let d _WTL be the total lens length at the wide-angle end (the length from the apex of the lens surface closest to the object side to the image plane). The distance from the aperture stop SP to the most object-side surface vertex of the lens unit LB at the wide angle end is _defined as d _WSB . The distance from the aperture stop SP to the most object-side surface vertex of the lens unit LB at the telephoto end is _{defined as dTSB} .

The average refractive index of the material of the positive lens and the average refractive index of the material of the negative lens included in the first lens unit L1 are N _av1P and N _av1N , respectively. The average refractive index of the positive lens material and the average refractive index of the negative lens material included in the lens group LA are N _avAP and N _avAN , respectively. At this time, one or more of the following conditional expressions should be satisfied.
0.01 <d _LS / d _WTL <0.30 (3)
1.5 <d _TSB / d _WSB <25.0 (4)
1.48 <N _av1P <2.2 (5)
1.70 <N _av1N <2.5 (6)
1.55 <N _avAP <2.2 (7)
1.70 <N _avAN <2.5 (8)

  Next, the technical meaning of each conditional expression described above will be described. Conditional expression (3) relates to the positions of the lens group LA, the lens group LB, and the aperture stop SP in the optical path at the wide angle end. As described above, at the wide-angle end, the lens group LA and the lens group LB are in a canceling relationship for correcting chromatic aberration, and the amount of axial chromatic aberration is adjusted. Therefore, in order to effectively correct the longitudinal chromatic aberration by the canceling relationship, it is preferable that the lens group LA and the lens group LB are close to each other on the optical axis. In addition, since the positional relationship in which axial chromatic aberration is corrected and the chromatic aberration of magnification is not significantly affected is preferable, the lens group LA and the lens group LB are preferably located in the vicinity of the aperture stop SP.

  If the upper limit value of conditional expression (3) is exceeded, the distance between the lens unit LA and the aperture stop SP and the lens unit LB becomes too large. For this reason, it is difficult to effectively create a chromatic aberration correction canceling relationship without significantly affecting other aberrations. On the other hand, when the lower limit value of conditional expression (3) is exceeded, the lens group LA, the lens group LB, and the aperture stop SP are close to each other, so that it is easy to create a chromatic aberration correction canceling relationship, but the lens group thickness becomes too thin. For this reason, it becomes difficult to apply appropriate power to the lenses in each lens group, and it becomes difficult to correct spherical aberration and coma.

The numerical range of conditional expression (3) is more preferably set as follows.
0.02 <d _LS / d _WTL <0.25 (3a)
The numerical range of conditional expression (3a) is more preferably set as follows.
0.05 <d _LS / d _WTL <0.20 (3b)

  Conditional expression (4) relates to the positional relationship between the lens unit LB and the aperture stop SP at the wide-angle end and the telephoto end. In order to effectively correct the lateral chromatic aberration with the lens unit LB at the telephoto end, it is preferable to dispose the lens unit LB at a position relatively away from the aperture stop SP. By doing so, the off-axis chief ray can pass around the lenses in the lens group LB, so that the lateral chromatic aberration can be effectively corrected without significantly affecting the axial chromatic aberration. In order to effectively correct axial chromatic aberration at the wide-angle end, it is preferable that the lens unit LB be positioned in the vicinity of the aperture stop SP.

  When the upper limit value of conditional expression (4) is exceeded, the distance between the lens unit LB and the aperture stop becomes too wide. In this case, although it is advantageous for correcting the lateral chromatic aberration, it is difficult to make the entire system compact. On the other hand, when the lower limit value of conditional expression (4) is exceeded, the amount of change in the distance between the lens unit LB and the aperture stop SP at the wide-angle end and the telephoto end is reduced. Then, it becomes difficult to effectively correct the lateral chromatic aberration at the telephoto end. The numerical range of conditional expression (4) is more preferably set as follows.

1.7 <d _TSB / d _WSB <20.0 (4a)
The numerical range of conditional expression (4a) is more preferably set as follows.
2.0 <d _TSB / d _WSB <15.0 (4b)

  Conditional expressions (5) to (8) relate to the refractive index of the material constituting the lenses included in the first lens unit L1 and the lens unit LA. The first lens unit L1 has a larger effective lens diameter than other lens units. In addition, the lens group LA has a larger power than the other lens groups. By increasing the refractive index of the material constituting each lens for such a lens group, the radius of curvature of the lens surface can be increased and the lens can be thinned, making it easy to make the entire system compact. become. In addition, astigmatism is facilitated because the radius of curvature of the lens surface can be increased.

  When the upper limit value of conditional expressions (5) to (8) is exceeded, the refractive index becomes too high. Therefore, although it is advantageous for making the entire system compact, it is difficult to achieve a good balance between Petzval sum and astigmatism correction, and field curvature and astigmatism remain.

  On the other hand, when the lower limit value of conditional expressions (5) to (8) is exceeded, the refractive index of each lens becomes too low. For this reason, in order to maintain the power of the first lens unit L1 and the lens unit LA, the radius of curvature of the lens surface must be reduced. This is not preferable because spherical aberration and astigmatism remain. The numerical ranges of conditional expressions (5) to (8) are more preferably set as follows.

1.48 <N _av1P <2.1 (5a)
1.73 <N _av1N <2.3 (6a)
1.55 <N _avAP <2.1 (7a)
1.73 <N _avAN <2.3 (8a)
The numerical ranges of conditional expressions (5a) to (8a) are more preferably set as follows.

1.48 <N _av1P <1.9 (5b)
1.75 <N _av1N <2.1 (6b)
1.55 <N _avAP <1.9 (7b)
1.75 <N _avAN <2.1 (8b)
In the zoom lens of each embodiment, it is preferable that the lens unit LA and the aperture stop SP move to the object side and the lens unit LB move to the image side during zooming from the wide-angle end to the telephoto end. In this way, at the telephoto end, the lens group LA can be disposed at a location where the axial paraxial light beam passes through a higher position from the optical axis.

  For this reason, since the power of the diffractive optical element DOE necessary for correcting the axial chromatic aberration at the telephoto end can be reduced, the diffractive optical element DOE can be easily manufactured. Further, by moving the lens unit LB to the image side, the distance from the aperture stop SP can be further increased at the telephoto end. In this way, the light beam in the lens unit LB is configured such that the paraxial axial light beam is lower than the optical axis and the off-axis principal ray passes through the lens periphery, so that the axial chromatic aberration is not significantly affected. It becomes easy to satisfactorily correct lateral chromatic aberration.

As described above, according to each embodiment, a zoom lens having high imaging performance can be easily obtained. In the lens cross-sectional views of each example, DOE is a diffractive optical element. D is a diffractive optical part (diffractive optical surface) constituting a part of the diffractive optical element DOE. Of the diffracted light generated from the diffractive optical part D, the diffraction order m of the diffracted light used in each embodiment is 1, and the design wavelength λ ₀ is the wavelength of the d-line (587.56 nm).

Note that the diffractive optical surface D provided on the zoom lens L0 is not limited to one, and a plurality of diffractive optical surfaces D may be used. According to this, even better optical performance can be obtained. The surface on which the diffractive optical surface D is provided is not limited to a spherical surface but may be an aspherical surface, and the base material may be glass or plastic as long as it transmits light. As for the shape of the diffraction grating, the phase φ (H) at the distance H from the optical axis is expressed by the following equation when the phase coefficient of the 2i-order term is C _2i . Where m is the diffraction order and λ ₀ is the reference wavelength.

In general, the Abbe number (dispersion value) ν _d of refractive optical materials such as lenses and prisms is d, C, F
When the refractive power at each wavelength of the line is N _d , N _C , N _F , it is expressed by the following formula.

ν _d = (N _d −1) / (N _F −N _C )> 0 (b)
On the other hand, the Abbe number ν _d of the diffractive optical unit is ν _d = λ _d / (λ _F −λ _C ) (c) when the wavelengths of the d, C, and F lines are λ _d , λ _C , and λ _F. )
Ν _d = −3.453.

The partial dispersion ratio θ _gF of the diffractive optical part D is θ _gF = (λ _g −λ _F ) / (λ _F −λ _C ) (d)
And θ _gF = 0.2956.

And the partial dispersion ratio difference of the diffractive optical part D is
Δθ _gF = θ _gF − (− 1.61783 × 10 ⁻³ × ν _d +0.64146) (e)
From the defining equation, Δθ _gF = −0.35145.

Thereby, the diffractive optical part D has a dispersibility at an arbitrary wavelength and has a reverse action to that of the refractive optical element. In addition, the refractive power φ _D of the paraxial temporary diffracted light (m = 1) at the reference wavelength of the diffractive optical part _D is expressed by the coefficient of the second-order term from the previous formula (a) representing the phase of the diffractive optical part as C ₂ Then, φ _D = −2 · C ₂ is expressed. From this, the focal length f _DOE by only the diffraction component of the diffractive optical element _DOE is

It becomes. Further, when the arbitrary wavelength is λ and the reference wavelength is λ ₀ , the refractive power change with respect to the reference wavelength of the arbitrary wavelength is expressed by the following equation.

φ _D '= (λ / λ ₀ ) × (−2 · C ₂ ) (g)
Thus, as a feature of the diffractive optical portion D, by varying the phase coefficients C ₂ of Equation (a), large dispersion can be obtained by a weak paraxial refractive power change. This means that chromatic aberration is corrected without greatly affecting various aberrations other than chromatic aberration. For the higher order coefficients after the phase coefficient C _4, the change in refractive power with respect to the change in the incident light height of the diffractive optical part D can provide an effect similar to that of an aspherical surface. At the same time, it is possible to change the refractive power at an arbitrary wavelength with respect to the reference wavelength according to the change in the incident light height. Therefore, the diffractive optical part D is effective for correcting lateral chromatic aberration.

Next, the configuration in each embodiment will be described.
[Example 1]
The configuration of the zoom lens L0 of Example 1 shown in FIGS. 1A and 1B will be described. The zoom lens L0 according to the first exemplary embodiment includes, in order from the object side to the image side, a first lens unit L1 having a positive refractive power, a second lens unit L2 having a negative refractive power, and a third lens unit L3 having a positive refractive power. doing. On the image side of the third lens unit L3, there are an aperture stop SP, a fourth lens unit L4 having a negative refractive power, a fifth lens unit L5 having a positive refractive power, and a sixth lens unit L6 having a negative refractive power. It is configured. The lens group LN corresponds to the second lens group L2. The lens group LA corresponds to the third lens group L3, and the lens group LB corresponds to the fourth lens group L4.

  The cemented lens in the third lens unit L3 constitutes a diffractive optical element DOE. The diffractive optical part D constituting the diffractive optical element DOE is arranged on the cemented surface of the cemented lens. During zooming, the second lens unit L2 does not move, and zooming is performed by moving other lens units. During zooming from the wide-angle end to the telephoto end, the first lens unit L1, the third lens unit L3, and the sixth lens unit L6 are moved toward the object side while changing the interval between the lens units. The fourth lens unit L4 moves so that the distance from the third lens unit L3 is increased. The fifth lens unit L5 moves so that the distance from the fourth lens unit L4 is narrow.

  The aperture stop SP is disposed between the third lens unit L3 and the fourth lens unit L4, and moves together with the third lens unit L3 (same locus) during zooming. Note that focusing from an infinite object to a short-distance object is performed by moving the sixth lens unit L6 on the optical axis to the image plane side and moving the fourth lens unit L4 to the object side on the optical axis and floating. ing.

[Example 2]
The configuration of the zoom lens L0 of Example 2 shown in FIGS. 3A and 3B will be described. The zoom lens L0 according to the second exemplary embodiment includes, in order from the object side to the image side, a first lens unit L1 having a positive refractive power, a second lens unit L2 having a negative refractive power, and a third lens unit L3 having a positive refractive power. doing. On the image side of the third lens unit L3, there are an aperture stop SP, a fourth lens unit L4 having a negative refractive power, a fifth lens unit L5 having a positive refractive power, and a sixth lens unit L6 having a negative refractive power. It is configured. The lens group LN corresponds to the second lens group L2. The lens group LA corresponds to the third lens group L3, and the lens group LB corresponds to the fourth lens group L4.

  The cemented lens in the third lens unit L3 constitutes a diffractive optical element DOE. The diffractive optical part D constituting the diffractive optical element DOE is arranged on the cemented surface of the cemented lens. During zooming, the third lens unit L3 does not move, and zooming is performed by moving other lens units. During zooming from the wide-angle end to the telephoto end, the first lens unit L1 and the sixth lens unit L6 move to the object side while changing the distance between the lens units. The second lens unit L2 moves to the image side. The fourth lens unit L4 moves so that the distance from the third lens unit L3 is increased.

  The fifth lens unit L5 moves so that the distance from the fourth lens unit L4 is narrow. The aperture stop SP is disposed between the third lens unit L3 and the fourth lens unit L4, and does not move during zooming. Note that focusing from an infinite object to a short-distance object is performed by moving the sixth lens unit L6 on the optical axis to the image plane side and moving the fourth lens unit L4 to the object side on the optical axis and floating. ing.

[Example 3]
The configuration of the zoom lens L0 of Example 3 shown in FIGS. 5A and 5B will be described. The zoom lens L0 according to the third exemplary embodiment includes, in order from the object side to the image side, a first lens unit L1 having a positive refractive power, a second lens unit L2 having a negative refractive power, and a third lens unit L3 having a positive refractive power. doing. On the image side of the third lens unit L3, there are an aperture stop SP, a fourth lens unit L4 with positive refractive power, a fifth lens unit L5 with negative refractive power, a sixth lens unit L6 with positive refractive power, and a negative lens unit. The seventh lens unit L7 having a refractive power of 6 is followed. The lens group LN corresponds to the second lens group L2. The lens group LA corresponds to the fourth lens group L4, and the lens group LB corresponds to the fifth lens group L5.

  The cemented lens in the fourth lens unit L4 constitutes a diffractive optical element DOE. The diffractive optical part D constituting the diffractive optical element DOE is arranged on the cemented surface of the cemented lens. During zooming, the second lens unit L2 and the fifth lens unit L5 do not move, and zooming is performed by moving the other lens units while changing the interval between the lens units. During zooming from the wide-angle end to the telephoto end, the fourth lens unit L4 moves so that the distance from the fifth lens unit L5 increases. The aperture stop SP is disposed between the third lens unit L3 and the fourth lens unit L4, and moves independently of other lens units (with different trajectories) during zooming.

  Specifically, during zooming from the wide-angle end to the telephoto end, the lens moves while changing the distance from the fourth lens unit L4. Note that focusing from an infinite object to a close object is performed by moving the seventh lens unit L7 on the optical axis to the image plane side and moving the fifth lens unit L5 to the object side on the optical axis and floating. ing.

[Example 4]
The configuration of the zoom lens L0 according to the fourth embodiment shown in FIGS. 7A and 7B will be described. The zoom lens L0 according to the fourth exemplary embodiment includes, in order from the object side to the image side, a first lens unit L1 having a positive refractive power, a second lens unit L2 having a negative refractive power, and a third lens unit L3 having a negative refractive power. doing. On the image side of the third lens unit L3, a fourth lens unit L4 having a positive refractive power including the aperture stop SP, a fifth lens unit L5 having a negative refractive power, a sixth lens unit L6 having a positive refractive power, and a negative The seventh lens unit L7 having a refractive power of 6 is followed.

  The lens group LN corresponds to the second lens group L2. The lens group LA corresponds to the fourth lens group L4, and the lens group LB corresponds to the fifth lens group L5. The cemented lens in the fourth lens unit L4 constitutes a diffractive optical element DOE. The diffractive optical part D constituting the diffractive optical element DOE is arranged on the cemented surface of the cemented lens. During zooming, the third lens unit L3 does not move, and zooming is performed by moving other lens units.

  During zooming from the wide-angle end to the telephoto end, the first lens unit L1, the second lens unit L2, the fourth lens unit L4, the sixth lens unit L6, and the seventh lens unit L7 are spaced apart from each other on the object side. Moving while changing. The fifth lens unit L5 moves so that the distance from the fourth lens unit L4 is increased. The aperture stop SP is disposed inside the fourth lens unit L4 and moves together with the fourth lens unit L4 during zooming. Note that focusing from an infinite object to a close object is performed by moving the seventh lens unit L7 on the optical axis to the image plane side and moving the fifth lens unit L5 to the object side on the optical axis and floating. ing.

[Example 5]
The configuration of the zoom lens L0 of Example 5 shown in FIGS. 9A and 9B will be described. The zoom lens L0 according to the fifth exemplary embodiment includes, in order from the object side to the image side, a first lens unit L1 having a positive refractive power, a second lens unit L2 having a negative refractive power, and a third lens unit L3 having a positive refractive power. doing. On the image side of the third lens unit L3, there are an aperture stop SP, a fourth lens unit L4 having a positive refractive power, a fifth lens unit L5 having a negative refractive power, a sixth lens unit L6 having a positive refractive power, and a negative lens unit. Continuing on from the seventh lens unit L7 having refractive power.

  The lens group LN corresponds to the second lens group L2. The lens group LA corresponds to the third lens group L3, and the lens group LB corresponds to the fourth lens group L4. The cemented lens in the third lens unit L3 and the cemented lens in the fourth lens unit L4 constitute a diffractive optical element DOE. The diffractive optical part D constituting the diffractive optical element DOE is arranged on the cemented surface of each cemented lens. During zooming, the second lens unit L2 does not move. Zooming is performed by moving the other lens groups.

  During zooming from the wide-angle end to the telephoto end, the first lens unit L1, the third lens unit L3, the sixth lens unit L6, and the seventh lens unit L7 move to the object side while changing the distance between the lens units. Yes. The fourth lens unit L4 moves so that the distance from the third lens unit L3 is increased. The fifth lens unit L5 moves so that the distance from the sixth lens unit L6 is narrow. The aperture stop is disposed between the third lens unit L3 and the fourth lens unit L4, and moves together with the third lens unit L3 during zooming.

  Note that focusing from an infinite object to a close object is performed by moving the seventh lens unit L7 on the optical axis to the image plane side and moving the fifth lens unit L5 to the object side on the optical axis and floating. ing.

[Example 6]
The configuration of the zoom lens L0 according to the sixth embodiment illustrated in FIGS. 11A and 11B will be described. The zoom lens L0 according to the sixth exemplary embodiment includes, in order from the object side to the image side, a first lens unit L1 having a positive refractive power, a second lens unit L2 having a positive refractive power, and a third lens unit L3 having a negative refractive power. doing. On the image side of the third lens unit L3, a fourth lens unit L4 having a positive refractive power, an aperture stop SP, a fifth lens unit L5 having a negative refractive power, a sixth lens unit L6 having a positive refractive power, and a negative lens unit The seventh lens unit L7 has a refractive power and the eighth lens unit L8 has a positive refractive power.

  The lens group LN corresponds to the third lens group L3. The lens group LA corresponds to the fourth lens group L4, and the lens group LB corresponds to the fifth lens group L5. The cemented lens in the fourth lens unit L4 constitutes a diffractive optical element DOE. The diffractive optical part D constituting the diffractive optical element DOE is arranged on the cemented surface of the cemented lens. The most image side lens surface of the cemented lens of the fourth lens unit L4 has an aspherical shape. During zooming, the third lens unit L3, the sixth lens unit L6, and the eighth lens unit L8 do not move, and zooming is performed by moving the other lens units.

  During zooming from the wide-angle end to the telephoto end, the first lens unit L1, the second lens unit L2, the fourth lens unit L4, and the seventh lens unit L7 are moved to the object side while changing the interval of each unit. . The fifth lens unit L5 moves so that the distance from the fourth lens unit L4 is increased. The aperture stop SP is disposed between the fourth lens unit L4 and the fifth lens unit L5, and moves together with the fourth lens unit L4 during zooming. Note that focusing from an infinitely distant object to a close object is performed by moving the seventh lens unit L7 on the optical axis to the image plane side.

  Numerical examples 1 to 6 corresponding to the first to sixth embodiments of the present invention are shown below. In each numerical example, i indicates the order of the surfaces from the object side, ri is the radius of curvature of the i-th surface from the object side, di is the i-th and i + 1-th distance from the object side, and ndi and νdi Are the refractive index and Abbe number of the i-th optical member. θgF is a partial dispersion ratio, and ΔθgF is a partial dispersion ratio difference. f, Fno, and 2ω respectively represent the focal length, F number, and angle of view (degree) of the entire system when focusing on an object at infinity. BF is the back focus in terms of air.

  The diffractive optical element (diffractive surface) is expressed by giving a phase coefficient of the phase function of the above-described equation (a). The aspherical shape is the X axis in the optical axis direction, the H axis in the direction perpendicular to the optical axis, the light traveling direction is positive, R is the paraxial radius of curvature, k is the eccentricity, and A4, A6, A8, and A10 are each aspherical. As a coefficient

It is expressed by the following formula. Further, for example, “e-Z” means “10-Z”. Table 1 shows the relationship between the above-described conditional expressions and numerical values in the numerical examples.

(Numerical example 1)
f = 103.00〜200.00〜388.94mm Fno = 4.63〜5.24〜5.83 2ω = 23.72〜12.34〜6.36 °
Surface number rd nd νd Effective diameter θgF ΔθgF
1 88.497 6.47 1.65160 58.5 66.71
2 376.894 0.15 66.27
3 118.227 2.80 1.88300 40.8 64.95
4 54.059 12.07 1.48749 70.2 61.21
5 1063.625 (variable) 60.40
6 -268.576 1.40 1.72916 54.7 32.19
7 70.009 3.85 31.59
8 -68.480 1.50 1.59282 68.6 31.61
9 118.472 2.22 1.84666 23.8 32.55
10 -661.138 (variable) 32.67
11 98.002 6.23 1.65160 58.5 33.48 0.54178 -0.00497
12 (Diffraction) -51.658 2.00 1.80000 29.8 33.47 0.60187 0.00870
13 -94.266 4.00 33.63
14 (Aperture) ∞ (Variable) 32.49
15 -48.874 2.10 1.43387 95.1 27.82 0.53728 0.04975
16 56.005 3.33 1.61340 44.3 28.36 0.56277 -0.00709
17 -930.171 (variable) 28.55
18 127.169 3.50 1.51633 64.1 29.15
19 -124.292 0.50 29.24
20 455.327 1.60 1.84666 23.8 29.18
21 51.821 1.83 29.00
22 272.073 2.99 1.48749 70.2 29.06
23 -83.387 0.15 29.38
24 44.467 4.27 1.61772 49.8 30.14
25 -824.972 (variable) 29.90
26 246.686 1.35 1.83481 42.7 29.18
27 41.889 4.47 1.72825 28.5 28.47
28 -208.021 1.35 1.77250 49.6 28.20
29 48.938 (variable) 27.55
Image plane ∞

Aspheric data 12th surface (diffractive surface)
C 2 = -1.31240e-004 C 4 = 6.04700e-008 C 6 = -7.36967e-011

Various data Zoom ratio 3.78
Wide angle Medium Telephoto focal length 103.00 200.00 388.94
F number 4.63 5.24 5.83
Half angle of view (degrees) 11.86 6.17 3.18
Image height 21.64 21.64 21.64
Total lens length 228.82 273.58 303.10
BF 69.48 90.93 105.73

d 5 2.00 46.77 76.28
d10 31.75 19.74 2.00
d14 7.82 16.60 45.00
d17 24.42 13.86 2.00
d25 23.20 15.56 1.95
d29 69.48 90.93 105.73

Entrance pupil position 57.65 163.71 266.80
Exit pupil position -47.86 -44.91 -53.63
Front principal point position 70.24 69.26 -293.52
Rear principal point position -33.52 -109.07 -283.21

The distance between each group at the closest position (1800mm from the image plane relative to infinity)
Wide angle Medium telephoto
d 5 2.00 46.77 76.28
d10 31.75 19.74 2.00
d14 4.71 13.48 41.89
d17 27.53 16.97 5.11
d25 25.52 21.11 18.21
d29 67.17 85.38 89.47

Zoom lens group data group Start surface Focal length Lens configuration length Front principal point position Rear principal point position
1 1 179.89 21.49 -4.15 -17.52
2 6 -53.88 8.98 1.51 -5.28
3 11 81.04 12.23 2.57 -6.40
4 15 -201.84 5.43 -1.42 -4.97
5 18 61.73 14.84 7.76 -2.71
6 26 -66.36 7.17 4.46 0.34

Single lens Data lens Start surface Focal length
1 1 175.93
2 3 -115.16
3 4 116.38
4 6 -76.03
5 8 -72.98
6 9 118.82
7 11 52.78 (value of a single lens excluding diffractive optical elements)
8 12 -145.91 (value of a single lens excluding diffractive optical elements)
9 15 -59.79
10 16 86.23
11 18 122.32
12 20 -69.19
13 22 131.29
14 24 68.43
15 26 -60.62
16 27 48.24
17 28 -51.17

ΔθgF = θgF − (− 1.61783 × 10 ⁻³ × ν _d +0.64146)
Is defined by the following formula.

(Numerical example 2)
f = 102.68〜200.00〜388.94mm Fno = 4.63〜5.21〜5.83 2ω = 23.80〜12.34〜6.36 °
Surface number rd nd νd Effective diameter θgF ΔθgF
1 86.565 6.57 1.65160 58.5 66.71
2 363.942 0.15 66.26
3 108.871 2.80 1.88300 40.8 64.78
4 52.104 10.87 1.48749 70.2 60.85
5 486.405 (variable) 60.26
6 -220.264 1.40 1.72916 54.7 27.14
7 57.012 4.32 26.60
8 -51.649 1.50 1.59282 68.6 26.67
9 199.227 1.88 1.84666 23.8 27.57
10 -193.519 (variable) 27.74
11 109.842 5.75 1.65 160 58.5 30.37 0.54178 -0.00497
12 (Diffraction) -44.240 2.00 1.80000 29.8 30.42 0.60187 0.00870
13 -68.862 4.00 30.65
14 (Aperture) ∞ (Variable) 29.41
15 -44.279 2.10 1.43387 95.1 28.86 0.53728 0.04975
16 65.118 4.73 1.61340 44.3 29.59 0.56277 -0.00709
17 -209.930 (variable) 29.73
18 95.261 3.50 1.48749 70.2 29.67
19 -118.165 0.50 29.53
20 -304.036 1.60 1.84666 23.8 29.22
21 54.010 1.94 28.80
22 636.101 2.84 1.48749 70.2 28.85
23 -77.246 0.15 29.07
24 47.965 5.47 1.59551 39.2 29.33
25 -155.393 (variable) 28.84
26 698.314 1.35 1.85026 32.3 28.14
27 28.690 6.05 1.78472 25.7 27.45
28 -89.223 1.35 1.88300 40.8 27.28
29 65.492 (variable) 26.94
Image plane ∞

Aspheric data 12th surface (diffractive surface)
C 2 = -1.47970e-004 C 4 = 7.35788e-008 C 6 = -8.21054e-011

Various data Zoom ratio 3.79
Wide angle Medium Telephoto focal length 102.68 200.00 388.94
F number 4.63 5.21 5.83
Half angle of view (degrees) 11.90 6.17 3.18
Image height 21.64 21.64 21.64
Total lens length 230.00 286.63 303.10
BF 61.00 77.54 81.23

d 5 2.00 59.73 90.10
d10 25.00 23.90 10.00
d14 6.70 14.78 45.00
d17 31.83 19.73 2.00
d25 30.65 18.13 1.95
d29 61.00 77.54 81.23

Entrance pupil position 50.00 217.69 404.61
Exit pupil position -51.38 -47.60 -52.52
Front principal point position 58.86 98.05 -337.51
Rear principal point position -41.68 -122.46 -307.71

The distance between each group at the closest position (1800mm from the image plane relative to infinity)
d 5 2.00 59.73 90.10
d10 25.00 23.90 10.00
d14 3.52 11.60 41.82
d17 35.01 22.92 5.18
d25 33.24 24.62 23.18
d29 58.40 71.05 60.00

Zoom lens group data group Start surface Focal length Lens configuration length Front principal point position Rear principal point position
1 1 180.36 20.39 -5.23 -17.72
2 6 -45.22 9.10 1.36 -5.73
3 11 70.05 11.75 3.00 -5.68
4 15 -251.37 6.83 -4.24 -8.77
5 18 68.74 16.00 9.47 -1.81
6 26 -63.66 8.75 4.55 -0.27

Single lens Data lens Start surface Focal length
1 1 172.70
2 3 -115.85
3 4 118.73
4 6 -61.98
5 8 -69.03
6 9 116.20
7 11 49.12 (value of a single lens excluding diffractive optical elements)
8 12 -160.46 (value of single lens excluding diffractive optical element)
9 15 -60.40
10 16 81.56
11 18 108.78
12 20 -54.06
13 22 141.48
14 24 62.17
15 26 -35.22
16 27 28.30
17 28 -42.60

ΔθgF = θgF − (− 1.61783 × 10 ⁻³ × ν _d +0.64146)
Is defined by the following formula.

(Numerical Example 3)
f = 102.17〜200.00〜388.94mm Fno = 4.62〜5.01〜5.83 2ω = 23.92〜12.34〜6.36 °
Surface number rd nd νd Effective diameter θgF ΔθgF
1 83.266 6.65 1.65 160 58.5 66.71
2 318.753 0.15 66.24
3 133.722 2.80 1.88300 40.8 65.20
4 54.440 11.55 1.51633 64.1 61.40
5 490.862 (variable) 60.62
6 -346.658 1.40 1.72916 54.7 33.35
7 213.269 2.72 32.99
8 -125.851 1.50 1.59282 68.6 32.85
9 41.551 2.07 1.84666 23.8 32.89
10 61.552 (variable) 32.80
11 87.762 3.73 1.65160 58.5 34.01
12 -2130.595 (variable) 34.02
13 (Aperture) ∞ (Variable) 34.01
14 135.083 5.30 1.65 160 58.5 34.00 0.54178 -0.00497
15 (Diffraction) -65.201 2.00 1.80000 29.8 33.80 0.60187 0.00870
16 -156.856 (variable) 33.61
17 -43.568 2.10 1.43387 95.1 26.26 0.53728 0.04975
18 72.407 2.68 1.61340 44.3 27.31 0.56277 -0.00709
19 4533.558 (variable) 27.48
20 748.730 3.50 1.51633 64.1 27.92
21 -63.652 0.50 28.15
22 -1343.760 1.60 1.84666 23.8 28.06
23 56.953 1.63 28.01
24 367.872 2.87 1.48749 70.2 28.07
25 -78.355 0.15 28.40
26 49.161 4.30 1.58144 40.8 29.13
27 -177.961 (variable) 28.98
28 -801.788 1.35 1.77250 49.6 28.34
29 33.766 4.02 1.72825 28.5 27.76
30 204.106 1.35 1.77250 49.6 27.59
31 58.459 (variable) 27.31
Image plane ∞

Aspheric data 15th surface (diffractive surface)
C 2 = -1.29311e-004 C 4 = -1.37648e-008 C 6 = -4.71506e-011

Various data Zoom ratio 3.81
Wide angle Medium telephoto focal length
F number 4.62 5.01 5.83
Half angle of view (degrees) 11.96 6.17 3.18
Image height 21.64 21.64 21.64
Total lens length 221.70 277.32 303.10
BF 55.00 75.81 94.31

d 5 2.00 57.61 83.40
d10 25.00 20.58 5.06
d12 22.14 6.49 2.36
d13 2.00 11.06 2.00
d16 6.40 17.42 46.13
d19 12.27 4.19 2.00
d27 30.99 18.26 1.95
d31 55.00 75.81 94.31

Entrance pupil position 65.07 192.47 262.10
Exit pupil position -42.70 -47.23 -54.28
Front principal point position 60.38 67.37 -367.03
Rear principal point position -47.17 -124.19 -294.63

The distance between each group at the closest position (1800mm from the image plane relative to infinity)
d 5 2.00 57.61 83.40
d10 25.00 20.58 5.06
d12 22.14 6.49 2.36
d13 2.00 11.06 2.00
d16 2.62 13.65 42.35
d19 16.05 7.97 5.78
d27 34.45 25.75 21.31
d31 51.54 68.32 74.95

Zoom lens group data group Start surface Focal length Lens configuration length Front principal point position Rear principal point position
1 1 204.56 21.14 -6.69 -19.44
2 6 -54.86 7.68 3.79 -1.70
3 11 129.44 3.73 0.09 -2.17
4 13 ∞ 0.00 0.00 -0.00
5 14 127.51 7.30 1.99 -2.38
6 17 -131.89 4.78 -0.42 -3.55
7 20 61.84 14.54 8.42 -1.73
8 28 -65.06 6.72 3.33 -0.49

Single lens Data lens Start surface Focal length
1 1 171.07
2 3 -105.74
3 4 117.53
4 6 -180.89
5 8 -52.52
6 9 144.19
7 11 129.44
8 14 68.20 (value of a single lens excluding a diffractive optical element)
9 15 -140.84 (value of single lens excluding diffractive optical element)
10 17 -62.35
11 18 119.93
12 20 113.79
13 22 -64.50
14 24 132.79
15 26 66.71
16 28 -41.91
17 29 55.01
18 30 -106.48

ΔθgF = θgF − (− 1.61783 × 10 ⁻³ × ν _d +0.64146)
Is defined by the following formula.

(Numerical example 4)
f = 103.00〜200.10〜388.92mm Fno = 4.28〜4.74〜5.83 2ω = 23.72〜12.34〜6.36 °
Surface number rd nd νd Effective diameter θgF ΔθgF
1 93.800 6.81 1.72916 54.7 66.71
2 412.768 (variable) 66.08
3 150.583 2.80 1.80 100 35.0 60.77
4 50.270 10.32 1.51823 58.9 57.13
5 682.415 (variable) 56.61
6 -148.061 1.40 1.72916 54.7 33.62
7 84.805 4.20 33.21
8 -90.081 1.50 1.59282 68.6 33.32
9 76.235 2.73 1.84666 23.8 34.38
10 1157.364 (variable) 34.48
11 92.277 5.33 1.64769 33.8 35.34 0.59447 0.00770
12 -96.735 1.00 35.32
13 (Aperture) ∞ 1.00 34.64
14 89.576 6.08 1.65 160 58.5 33.95 0.54178 -0.00497
15 (Diffraction) -57.675 2.00 1.80000 29.8 33.32 0.60187 0.00870
16 118.065 (variable) 32.01
17 -49.322 2.10 1.43387 95.1 27.82 0.53728 0.04975
18 101.700 2.41 1.61340 44.3 28.95 0.56277 -0.00709
19 4578.450 (variable) 29.18
20 114.055 3.50 1.54814 45.8 29.97
21 -102.268 0.50 30.08
22 -4886.561 1.60 1.84666 23.8 30.01
23 55.238 1.74 29.93
24 235.496 3.01 1.48749 70.2 30.00
25 -93.840 0.15 30.34
26 49.549 5.51 1.61340 44.3 31.25
27 -247.405 (variable) 30.97
28 318.603 1.35 1.77250 49.6 29.46
29 97.846 5.11 1.72825 28.5 29.07
30 -67.707 1.35 1.77250 49.6 28.61
31 48.751 (variable) 27.79
Image plane ∞

Aspheric data 15th surface (diffractive surface)
C 2 = -1.52692e-004 C 4 = 5.80181e-008 C 6 = -9.99607e-011

Various data Zoom ratio 3.78
Wide angle Medium telephoto focal length 103.00 200.10 388.92
F number 4.28 4.74 5.83
Half angle of view (degrees) 11.86 6.17 3.18
Image height 21.64 21.64 21.64
Total lens length 230.00 276.89 303.10
BF 58.53 76.88 98.35

d 2 0.15 7.29 10.54
d 5 4.04 43.80 66.75
d10 30.00 22.44 2.00
d16 9.70 24.07 45.00
d19 25.14 10.85 2.00
d27 28.93 18.06 4.94
d31 58.53 76.88 98.35

Entrance pupil position 55.53 167.52 237.28
Exit pupil position -56.79 -52.62 -56.41
Front principal point position 66.53 58.43 -351.13
Rear principal point position -44.47 -123.22 -290.57

The distance between each group at the closest position (1800mm from the image plane relative to infinity)
d 2 0.15 7.29 10.54
d 5 4.04 43.80 66.75
d10 30.00 22.44 2.00
d16 4.49 18.86 39.79
d19 30.35 16.06 7.21
d27 31.97 25.81 24.92
d31 55.48 69.14 78.37

Zoom lens group data group Start surface Focal length Lens configuration length Front principal point position Rear principal point position
1 1 164.99 6.81 -1.15 -5.05
2 3 -986.57 13.12 14.93 6.42
3 6 -56.34 9.83 1.44 -5.93
4 11 78.73 15.42 -2.05 -11.48
5 17 -139.94 4.51 -0.31 -3.27
6 20 59.69 16.01 7.64 -3.54
7 28 -69.52 7.81 5.13 0.60

Single lens Data lens Start surface Focal length
1 1 164.99
2 3 -95.40
3 4 104.14
4 6 -73.76
5 8 -69.42
6 9 96.28
7 11 73.73
8 14 54.74 (value of a single lens excluding diffractive optical elements)
9 15 -48.19 (value of single lens excluding diffractive optical element)
10 17 -76.23
11 18 169.53
12 20 98.94
13 22 -64.50
14 24 138.06
15 26 67.78
16 28 -183.29
17 29 55.67
18 30 -36.51

ΔθgF = θgF − (− 1.61783 × 10 ⁻³ × ν _d +0.64146)
Is defined by the following formula.

(Numerical example 5)
f = 103.01 ~ 200.01 ~ 388.96mm Fno = 4.63 ~ 5.32 ~ 5.83 2ω = 23.72 ~ 12.34 ~ 6.36 °
Surface number rd nd νd Effective diameter θgF ΔθgF
1 87.070 6.55 1.65160 58.5 66.72
2 367.977 0.15 66.27
3 121.123 2.80 1.88300 40.8 64.99
4 53.839 11.15 1.48749 70.2 61.19
5 1174.897 (variable) 60.67
6 -160.340 1.40 1.85026 32.3 33.45
7 62.523 5.12 33.01
8 -73.750 1.50 1.59282 68.6 33.30
9 68.041 4.21 1.84666 23.8 35.34
10 -162.179 (variable) 35.54
11 71.213 7.40 1.72916 54.7 36.78 0.54423 -0.00880
12 (Diffraction) -57.549 2.00 1.80000 29.8 36.59 0.60187 0.00870
13 -205.836 4.00 36.30
14 (Aperture) ∞ (Variable) 35.00
15 -73.838 2.00 1.80000 29.8 27.26 0.60187 0.00870
16 (Diffraction) -53.876 2.00 1.80000 29.8 27.39 0.60187 0.00870
17 -61.527 (variable) 27.58
18 -45.760 2.10 1.72916 54.7 26.63
19 -137.721 (variable) 27.39
20 171.610 3.50 1.48749 70.2 28.18
21 -83.414 0.50 28.36
22 165.576 1.60 1.75520 27.5 28.34
23 51.537 1.45 28.11
24 151.204 3.25 1.48749 70.2 28.15
25 -78.467 0.15 28.33
26 37.704 3.67 1.48749 70.2 28.43
27 161.985 (variable) 28.06
28 -1246.251 1.35 1.77250 49.6 27.71
29 56.214 3.69 1.72825 28.5 27.25
30 -179.001 1.35 1.77250 49.6 27.04
31 53.973 (variable) 26.58
Image plane ∞

Aspheric data 12th surface (diffractive surface)
C 2 = -1.41897e-004 C 4 = 3.75706e-008 C 6 = -4.64749e-011
16th surface (diffractive surface)
C 2 = 9.54619e-005 C 4 = 3.58948e-008 C 6 = -2.11119e-011

Various data Zoom ratio 3.78
Wide angle Medium telephoto focal length 103.01 200.01 388.96
F number 4.63 5.32 5.83
Half angle of view (degrees) 11.86 6.17 3.18
Image height 21.64 21.64 21.64
Total lens length 230.00 276.21 303.10
BF 61.00 79.85 106.13

d 5 2.00 48.21 75.10
d10 25.00 15.76 2.00
d14 3.27 12.12 40.00
d17 10.00 9.87 3.05
d19 29.71 20.42 2.00
d27 26.14 17.12 1.95
d31 61.00 79.85 106.13

Entrance pupil position 53.01 160.68 257.37
Exit pupil position -56.21 -53.14 -47.58
Front principal point position 65.49 59.88 -337.95
Rear principal point position -42.01 -120.17 -282.83

The distance between each group at the closest position (1800mm from the image plane relative to infinity)
d 5 2.00 48.21 75.10
d10 25.00 15.76 2.00
d14 3.27 12.12 40.00
d17 8.37 8.23 1.41
d19 31.35 22.05 3.63
d27 28.73 23.29 17.06
d31 58.41 73.67 91.01

Zoom lens group data group Start surface Focal length Lens configuration length Front principal point position Rear principal point position
1 1 182.64 20.64 -4.27 -17.07
2 6 -57.35 12.23 -0.94 -10.39
3 11 76.87 13.40 1.30 -8.17
4 15 436.58 4.00 12.52 10.61
5 18 -94.90 2.10 -0.61 -1.84
6 20 56.01 14.12 5.81 -4.36
7 28 -62.36 6.39 3.35 -0.30

Single lens Data lens Start surface Focal length
1 1 173.45
2 3 -111.95
3 4 115.37
4 6 -52.75
5 8 -59.46
6 9 57.09
7 11 44.73 (value of single lens excluding diffractive optical element)
8 12 -100.46 (value of single lens excluding diffractive optical element)
9 15 238.48 (value of single lens excluding diffractive optical element)
10 16 -612.75 (value of single lens excluding diffractive optical element)
11 18 -94.90
12 20 115.66
13 22 -99.69
14 24 106.46
15 26 99.84
16 28 -69.60
17 29 59.13
18 30 -53.55

ΔθgF = θgF − (− 1.61783 × 10 ⁻³ × ν _d +0.64146)
Is defined by the following formula.

(Numerical example 6)
f = 72.50〜135.00〜289.99mm Fno = 4.44〜5.04〜5.85 2ω = 33.24〜18.20〜8.54 °
Surface number rd nd νd Effective diameter θgF ΔθgF
1 65.305 5.42 1.49700 81.5 49.57
2 347.969 (variable) 49.20
3 60.149 2.20 1.83481 42.7 45.99
4 36.362 8.04 1.49700 81.5 43.35
5 202.320 (variable) 42.62
6 210.522 1.10 1.83400 37.2 18.99
7 43.219 2.75 18.47
8 -56.186 0.90 1.80400 46.6 18.32
9 28.127 2.71 1.84666 23.9 18.53
10 276.913 (variable) 18.60
11 46.292 1.20 1.80000 29.8 18.89 0.60187 0.00870
12 (Diffraction) 24.039 4.28 1.72916 54.7 18.67 0.54423 -0.00880
13 (Aspherical) -108.549 1.00 18.52
14 (Aperture) ∞ (Variable) 18.16
15 -23.380 1.90 1.43387 95.1 19.06 0.53728 0.04975
16 32.166 2.45 1.73800 32.3 21.28 0.59029 0.00104
17 76.190 (variable) 21.53
18 -1139.281 3.48 1.59282 68.6 21.91
19 -31.932 0.15 22.44
20 76.442 5.08 1.48749 70.2 22.80
21 -25.183 1.00 1.80518 25.4 22.77
22 -69.739 0.15 23.22
23 52.379 3.28 1.52249 59.8 23.26
24 -141.072 (variable) 23.05
25 -101.414 1.10 1.77250 49.6 22.70
26 40.464 1.92 22.45
27 -356.152 2.99 1.80518 25.4 22.50
28 -39.968 1.10 1.83481 42.7 22.82
29 84.565 (variable) 23.59
30 90.930 5.12 1.59270 35.3 36.56
31 -97.437 (variable) 36.92
Image plane ∞

Aspheric data 12th surface (diffractive surface)
C 2 = -1.13443e-004 C 4 = 5.58579e-007 C 6 = -1.41238e-008 C 8 = 8.59807e-011

Side 13
K = 6.29842e + 000 A 4 = 6.15032e-007 A 6 = 1.91106e-008 A 8 = -1.45408e-010
A10 = 7.02840e-014

Various data Zoom ratio 4.00
Wide angle Medium Telephoto focal length 72.50 135.00 289.99
F number 4.44 5.04 5.85
Half angle of view (degrees) 16.62 9.10 4.27
Image height 21.64 21.64 21.64
Total lens length 143.91 177.69 203.15
BF 39.10 39.10 39.10

d 2 0.15 7.06 6.00
d 5 1.30 28.17 54.69
d10 9.90 6.01 1.20
d14 4.03 13.07 21.89
d17 10.67 5.51 1.50
d24 16.46 14.31 1.30
d29 3.00 5.15 18.16
d31 39.10 39.10 39.10

Entrance pupil position 33.24 112.83 262.97
Exit pupil position -43.34 -50.42 -97.38
Front principal point position 41.98 44.25 -63.21
Rear principal point position -33.40 -95.90 -250.89

The distance between each group at the closest position (1400mm from the image plane relative to infinity)
d 2 0.15 7.06 6.00
d 5 1.30 28.17 54.69
d10 9.90 6.01 1.20
d14 4.03 13.07 21.89
d17 10.67 5.51 1.50
d24 17.26 16.91 10.44
d29 2.20 2.55 9.02
d31 39.10 39.10 39.10

Zoom lens group data group Start surface Focal length Lens configuration length Front principal point position Rear principal point position
1 1 160.73 5.42 -0.83 -4.43
2 3 418.34 10.24 -11.47 -17.62
3 6 -31.33 7.46 2.22 -3.03
4 11 47.64 6.48 0.92 -3.27
5 15 -52.87 4.35 0.73 -1.96
6 18 28.18 13.14 4.19 -4.66
7 25 -24.34 7.10 1.67 -2.98
8 30 80.17 5.12 1.57 -1.68

Single lens Data lens Start surface Focal length
1 1 160.73
2 3 -114.98
3 4 87.78
4 6 -65.40
5 8 -23.20
6 9 36.79
7 11 -64.05 (value of single lens excluding diffractive optical element)
8 12 27.36 (Value of a single lens excluding a diffractive optical element)
9 15 -30.89
10 16 73.69
11 18 55.35
12 20 39.50
13 21 -49.45
14 23 73.53
15 25 -37.32
16 27 55.68
17 28 -32.38
18 30 80.17

ΔθgF = θgF − (− 1.61783 × 10 ⁻³ × ν _d +0.64146)
Is defined by the following formula.

  “-” In the table represents a conditional expression that does not correspond to the numerical example.

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

  Next, an embodiment in which the zoom lens of the present invention is applied to an imaging apparatus (camera system) will be described with reference to FIG. FIG. 13 is a schematic view of the main part of a single-lens reflex camera. In FIG. 13, reference numeral 10 denotes an imaging lens having any one zoom lens 1 of the first to sixth embodiments. The zoom lens 1 is held by a lens barrel 2 that is a holding member.

  Reference numeral 20 denotes a camera body. The camera body 20 converts the quick return mirror 3 that reflects the light beam from the imaging lens 10 upward, the focusing screen 4 disposed at the image forming position of the imaging lens 10, and the inverted image formed on the focusing screen 4 into an erect image. A penta roof prism 5 is provided. Further, it is constituted by an eyepiece 6 for observing the erect image.

  Reference numeral 7 denotes a photosensitive surface, on which an image pickup device (photoelectric conversion device) such as a CCD sensor or a CMOS sensor, or a silver salt film is arranged. At the time of photographing, the quick return mirror 3 is retracted from the optical path, and an image is formed on the photosensitive surface 7 by the photographing lens 10. In this way, by applying the zoom lenses of Embodiments 1 to 6 to an imaging apparatus such as a photographic camera, a video camera, or a digital still camera, a small-sized imaging apparatus having high imaging performance is realized. Note that the zoom lens of the present invention can also be applied to an imaging apparatus without a quick return mirror.

  Next, an embodiment in which the zoom lens of the present invention is applied to a projection apparatus (projector) (optical apparatus) will be described with reference to FIG.

  In this figure, the zoom lens of the present invention is applied to a three-plate color liquid crystal projector, and image information of a plurality of color lights based on a plurality of liquid crystal display elements is synthesized through a color synthesizing means, and enlarged on the screen surface by the zoom lens 1 shows an image projection apparatus for projection. In FIG. 14, a color liquid crystal projector 100 combines RGB color lights from three R, G, and B panels, 5R, 5G, and 5B into a single optical path by a prism 200 as a color synthesizing unit. Then, the image is projected onto the screen 400 using the projection lens 300 composed of the zoom lens described above.

  Thus, by applying the zoom lenses of Numerical Examples 1 to 6 to a single-lens reflex camera, a digital camera, a projector, or the like, an optical apparatus having high imaging performance can be realized.

L0 zoom lens L1 first lens group L2 second lens group L3 third lens group L4 fourth lens group L5 fifth lens group L6 sixth lens group L7 seventh lens group L8 eighth lens group LN lens group LN LA lens group LA LB lens group LB
SP Aperture stop DOE Diffraction optical element D Diffraction optical section

Claims (12)

A first lens unit having a positive refractive power closest to the object side;
A plurality of lens units having negative refractive power closer to the image side than the first lens unit, an aperture stop, and
A lens group LA having a positive refractive power closer to the image side than a lens group LN located closest to the object side among the plurality of lens groups having a negative refractive power;
The lens unit LA and the lens unit LB having a positive or negative refractive power on the image side from the aperture stop,
A zoom lens in which the distance between the lens group LA and the lens group LB is widened during zooming from the wide-angle end to the telephoto end, and the distance between the aperture stop and the lens group LB is widened.
The lens group LA has one or more diffractive optical elements,
The total system power at the wide angle end is φ _w , the total system power at the telephoto end is φ _t , the chromatic aberration correction power of the lens group LA is SUM (A), and the chromatic aberration correction power of the lens group LB is SUM (B). and when,
-1.0 × 10 ^-3 <SUM (A) × SUM (B) / (φ _w × φ _t ) <-1.0 × 10 ^-6
0.1 <│SUM (A) / SUM (B) │ <6.0
A zoom lens satisfying the following conditional expression: Of the lens group LA and the aperture stop at the wide angle end, the distance from the most object side surface vertex of the element located closest to the object side to the most image side surface vertex of the lens group LB is d _LS , the wide angle end _Where d _{WTL is} the total lens length at
0.01 <d _LS / d _WTL <0.30
The zoom lens according to claim 1, wherein the following conditional expression is satisfied. The distance from the aperture stop to the most object-side surface vertex of the lens unit LB at the wide-angle end is d _WSB , and the distance from the aperture stop to the most object-side surface vertex of the lens unit LB at the telephoto end is d _{When TSB} ,
1.5 <d _TSB / d _WSB <25.0
The zoom lens according to claim 1, wherein the following conditional expression is satisfied. The lens unit LA and the aperture stop are moved to the object side, and the lens unit LB is moved to the image side during zooming from the wide-angle end to the telephoto end. Zoom lens. The average refractive index of the positive lens material and the average refractive index of the negative lens material included in the first lens group are N _av1P and N _av1N , and the average refractive index of the positive lens material _{included in} the lens group LA and the negative lens When the average refractive index of the material is N _avAP and N _avAN , respectively
1.48 <N _av1P <2.2
_1.70 <N av1N <2.5
1.55 <N _avAP <2.2
1.70 <N _avAN <2.5
The zoom lens according to claim 1, wherein the following conditional expression is satisfied. From the object side to the image side,
A first lens group having a positive refractive power, a second lens group having a negative refractive power, a third lens group having a positive refractive power, a fourth lens group having a negative refractive power, a fifth lens group having a positive refractive power, It consists of a sixth lens unit with negative refractive power,
During zooming, the second lens group does not move, and the other lens groups move.
6. The lens group LN corresponds to the second lens group, the lens group LA corresponds to the third lens group, and the lens group LB corresponds to the fourth lens group, respectively. The zoom lens according to any one of the above. From the object side to the image side,
A first lens group having a positive refractive power, a second lens group having a negative refractive power, a third lens group having a positive refractive power, a fourth lens group having a negative refractive power, a fifth lens group having a positive refractive power, It consists of a sixth lens unit with negative refractive power,
During zooming, the third lens group does not move, and the other lens groups move.
6. The lens group LN corresponds to the second lens group, the lens group LA corresponds to the third lens group, and the lens group LB corresponds to the fourth lens group, respectively. The zoom lens according to any one of the above. From the object side to the image side,
A first lens group having a positive refractive power, a second lens group having a negative refractive power, a third lens group having a positive refractive power, a fourth lens group having a positive refractive power, a fifth lens group having a negative refractive power, A sixth lens group having a positive refractive power and a seventh lens group having a negative refractive power;
During zooming, the second lens group and the fifth lens group do not move, and other lens groups move,
6. The lens group LN corresponds to the second lens group, the lens group LA corresponds to the fourth lens group, and the lens group LB corresponds to the fifth lens group, respectively. The zoom lens according to any one of the above. From the object side to the image side,
A first lens group having a positive refractive power, a second lens group having a negative refractive power, a third lens group having a negative refractive power, a fourth lens group having a positive refractive power, a fifth lens group having a negative refractive power, A sixth lens group having a positive refractive power and a seventh lens group having a negative refractive power;
During zooming, the third lens group does not move, and the other lens groups move.
6. The lens group LN corresponds to the second lens group, the lens group LA corresponds to the fourth lens group, and the lens group LB corresponds to the fifth lens group, respectively. The zoom lens according to any one of the above. From the object side to the image side,
A first lens group having a positive refractive power, a second lens group having a negative refractive power, a third lens group having a positive refractive power, a fourth lens group having a positive refractive power, a fifth lens group having a negative refractive power, A sixth lens group having a positive refractive power and a seventh lens group having a negative refractive power;
During zooming, the second lens group does not move, and the other lens groups move.
6. The lens group LN corresponds to the second lens group, the lens group LA corresponds to the third lens group, and the lens group LB corresponds to the fourth lens group, respectively. The zoom lens according to any one of the above. From the object side to the image side,
A first lens group having a positive refractive power, a second lens group having a positive refractive power, a third lens group having a negative refractive power, a fourth lens group having a positive refractive power, a fifth lens group having a negative refractive power, A sixth lens group having a positive refractive power, a seventh lens group having a negative refractive power, and an eighth lens group having a positive refractive power;
During zooming, the third lens group, the sixth lens group, and the eighth lens group do not move, and other lens groups move,
6. The lens group LN corresponds to the third lens group, the lens group LA corresponds to the fourth lens group, and the lens group LB corresponds to the fifth lens group, respectively. The zoom lens according to any one of the above. An optical apparatus comprising the zoom lens according to claim 1.