Zoom lens and image capture device

Abstract

A zoom lens (L0) comprises, in order from the object side to the image side, a first lens (L1) with negative refractive power, a second lens (L2), one or more intermediate lenses (LM), and a rear lens (LR). At least the second lens and the one or more intermediate lenses move during zooming, and the distance between each adjacent lens unit changes. The one or more intermediate lens units include an Nth intermediate lens unit located closest to an image plane, and the Nth intermediate lens unit includes a displacement unit (IS) with positive refractive power, located closest to the image plane and movable in a direction orthogonal to an optical axis of the zoom lens. A predetermined inequality is satisfied.

Description

TECHNICAL AREA

[0001] One of the aspects of the embodiments relates to a zoom lens or zoom objective for imaging and an image recording device that includes this. BACKGROUND Description of the related prior art

[0002] Some zoom lenses include a shifting unit that moves (shifts) in a direction orthogonal to the optical axis for image stabilization and similar purposes. The shifting unit must have a reduced size, weight, and range of motion to reduce the load on the actuator driving it. Japanese patent application No. 2021-196449 discloses a zoom lens that includes a shifting unit and performs zooming by moving a plurality of lens units. SUMMARY

[0003] The present disclosure, in its first aspect, provides a zoom lens as specified in claims 1 to 21.

[0004] The present disclosure, in its second aspect, provides an image recording device as specified in claim 22.

[0005] Further features of various embodiments of the disclosure will become apparent from the following description of the embodiments with reference to the accompanying drawings. Each of the embodiments of the present disclosure described below can be implemented alone or as a combination of a plurality of embodiments. Furthermore, features from different embodiments can be combined if necessary or if the combination of elements or features from individual embodiments in a single embodiment is advantageous. BRIEF DESCRIPTION OF THE DRAWINGS Fig. Figure 1 illustrates sectional views of a zoom lens according to Example 1 at the wide-angle end, in the middle zoom position and at the telephoto end. The Fig. 2A, Fig. 2B and Fig. Figure 2C illustrates aberration representations of the zoom lens according to Example 1 at the wide-angle end, in the middle zoom position and at the telephoto end. Fig. Figure 3 illustrates sectional views of a zoom lens according to Example 2 at the wide-angle end, in the middle zoom position and at the telephoto end. The Fig. 4A, Fig. 4B and Fig. Figure 4C illustrates aberration representations of the lens according to Example 2 at the wide-angle end, in the middle zoom position and at the telephoto end. Fig. Figure 5 illustrates sectional views of a zoom lens according to Example 3 at the wide-angle end, in the middle zoom position and at the telephoto end. The Fig. 6A, Fig. 6B and Fig.Figure 6C illustrates aberration representations of the lens according to Example 3 at the wide-angle end, in the middle zoom position and at the telephoto end. Fig. Figure 7 is a cross-sectional view of a zoom lens according to Example 4 at the wide-angle end, in the middle zoom position and at the telephoto end. The Fig. 8A, Fig. 8B and Fig. Figures 8C are aberration representations of the zoom lens according to Example 4 at the wide-angle end, in the middle zoom position and at the telephoto end. Fig. Figure 9 is a cross-sectional view of a zoom lens according to Example 5 at the wide-angle end, in the middle zoom position and at the telephoto end. The Fig. 10A, Fig. 10B and Fig. Figures 10C are aberration representations of the zoom lens according to Example 5 at the wide-angle end, in the middle zoom position and at the telephoto end. Fig.Figure 11 is a cross-sectional view of a zoom lens according to Example 6 at the wide-angle end, in the middle zoom position and at the telephoto end. The Fig. 12A, Fig. 12B and Fig. Figures 12C are aberration representations of the zoom lens according to Example 6 at the wide-angle end, in the middle zoom position and at the telephoto end. Fig. Figure 13 is a schematic representation of an image recording device with the zoom lens according to one of Examples 1 to 6. DESCRIPTION OF THE EXAMPLES OF EXECUTION

[0006] Examples from the disclosure are described with reference to the drawings. Before describing examples 1 to 6, the features common to all examples are described first.

[0007] The Fig. 1, Fig. 3, Fig. 5, Fig. 7, Fig. 9 and Fig.Figure 11 illustrates cross-sections of zoom lenses L0 according to Examples 1 to 6 in a focused state on an object at infinity (hereinafter referred to as "in a focused state at infinity") at the wide-angle end, the middle zoom position (MID), and the telephoto end. The zoom lens according to each example is used as an imaging optical system in a variety of image-capturing devices, such as digital video cameras, digital cameras with an image sensor, television cameras, film cameras, surveillance cameras, and on-board cameras (cameras in vehicles).

[0008] In each illustration, the left side is the object side and the right side is the image side. SP represents an aperture (diaphragm) that defines a light ray at the widest aperture (Fno) (maximum aperture). IP represents the image plane of the zoom lens L0. An image-receiving surface (light-receiving surface) of an image sensor, such as a CCD or CMOS sensor, or a film surface (light-sensitive surface) of a silver film, is located on the image plane IP.

[0009] The zoom lens L0 according to each example is designed to allow distortions, and the image distortions caused by distortions are corrected by processing the images, which is carried out by the image acquisition device using information about the degree of distortion.

[0010] The zoom lens L0 according to each example can also be used as a projection optics system in an image projection device such as a projector. In this case, the left side of the image is the screen side (magnification side) and the right side is the display side (reduction side).

[0011] In a zoom lens, a lens unit is a group of one or more lenses that may or may not move as a unit between the wide-angle end and the telephoto end during magnification changes (zooming). In other words, the distance between adjacent lens units changes during zooming. In each illustration, a solid arrow under a lens moving during zooming indicates the position of each lens as it zooms from the wide-angle end to the telephoto end. The wide-angle end and telephoto end, respectively, indicate the zoom state of the maximum angle of view (shortest focal length) and the minimum angle of view (longest focal length) when the lens unit moving during zooming is at either end of the mechanically or controllably movable range on the optical axis.The group of one or more lenses that moves during focusing is a focusing lens unit, and a dotted arrow above the focusing lens unit in each illustration indicates the direction of movement of the focusing lens unit during focusing from infinity to a near distance. The lens unit may also include an aperture (SP). In this example, the term "lens element" refers to a single lens or a cemented lens formed by bonding together multiple lenses.

[0012] The zoom lens L0, according to each example, comprises, in order from the object side to the image side, a first lens L1 with negative refractive power, a second lens L2, an intermediate group LM with one or more intermediate lenses, and a rear (subsequent) lens Lr. The intermediate group LM includes an Nth intermediate lens, which is positioned closest to the image plane within the intermediate group LM. An image stabilization unit IS with positive refractive power is positioned closest to the image plane among the Nth intermediate lens units. The image stabilization unit IS is a displacement unit that moves in a direction orthogonal to the optical axis of the zoom lens L0 to compensate for image blur caused by camera shake, such as hand movements.Movement in a direction orthogonal to the optical axis includes movement within a plane orthogonal to the optical axis, as illustrated by the up and down arrows in each figure, as well as movement in a direction that includes a component orthogonal to the optical axis (for example, rotation about a point on the optical axis). The translation unit can also move in a direction orthogonal to the optical axis for purposes other than image stabilization, such as tracking a moving object.

[0013] In the zoom lens L0 according to each example, the second lens unit L2 and the intermediate group LM (intermediate lens unit) can move towards the object during zooming from the wide-angle end to the telephoto end. The second lens unit L2 can have a positive refractive power, and the intermediate group LM can also have a positive refractive power overall. A zoom function can be achieved by moving the second lens unit L2 and the intermediate group LM, both of which have positive refractive powers, closer to the first lens unit L1, which has a negative refractive power.

[0014] The second lens unit L2 can comprise two or more lenses. This allows for satisfactory correction of spherical aberrations, coma, and other aberrations.

[0015] The Nth intermediate lens unit can have a positive refractive power and move towards the object during zooming from the wide-angle end to the telephoto end, while the distance to the second lens L2 increases. This corrects field curvature, reduces the range of motion of the Nth intermediate lens unit, and decreases its size and weight. Consequently, the load on the actuator that drives the Nth intermediate lens unit during zooming is reduced, resulting in fast and quiet zooming.

[0016] Since the compact and lightweight Nth intermediate lens unit incorporates the image stabilization (IS) unit, the size and weight of the image stabilization mechanism, including the actuator that drives the IS unit, can also be reduced. In particular, the IS unit positioned closest to the image plane among the Nth intermediate lens units allows for a further reduction in size and weight. This reduces the drive load during zooming and enables superior image stabilization performance.

[0017] The image stabilization unit (IS) can comprise two or more lenses, for example, a positive and a negative lens, or a cemented lens (which is counted as two lenses) where a positive and a negative lens are cemented together to form a single lens element. This helps to suppress fluctuations in chromatic aberration that occur during image stabilization. To reduce the overall size of the zoom lens (L0), the Nth intermediate lens unit can incorporate a single image stabilization unit (IS).

[0018] The zoom lens L0 according to each example can satisfy the following inequalities (1) and (2): 1.8≤fis / (−f1)≤4.8 0.05≤BFw / fw≤1.85

[0019] In inequalities (1) and (2), f1 is the focal length of the first lens L1 and fis is the focal length of the image stabilization unit IS. fw is the focal length of the zoom lens L0 at the wide-angle end. BFw is the air-equivalent distance (back focus) on the optical axis from the image plane IP of the lens closest to the zoom lens L0 to the image plane IP at the wide-angle end.

[0020] Inequality (1) defines a suitable relationship between the focal length of the first lens unit L1 and the focal length of the image stabilization unit IS. When fis / (-f1) exceeds the upper limit of inequality (1), the performance of the image stabilization unit IS is reduced, increasing the amount of movement required for image stabilization and the size of the image stabilization mechanism. Furthermore, as the performance of the first lens L1 increases, it becomes difficult to effectively correct off-axis aberrations such as field curvature. Conversely, when fis / (-f1) falls below the lower limit of inequality (1), the performance of the image stabilization unit IS increases, making it difficult to correct aberrations such as decentered coma during image stabilization, and insufficient image stabilization performance can be achieved.When the energy of the first lens unit L1 is reduced, the range of motion of the image stabilization unit IS (Nth intermediate lens unit) increases during zooming, and the size of the zoom lens L0 increases.

[0021] Inequality (2) defines a suitable relationship between the rear focus of the zoom lens L0 at the wide-angle end and the focal length of the zoom lens L0 at the wide-angle end. If BFw / fw exceeds the upper limit of inequality (2), the total optical length of the zoom lens L0 (a distance from one of the lens surfaces closest to the image plane IP) increases. If BFw / fw falls below the lower limit of inequality (2), a flange back cannot be adequately secured in the image-taking device, and positioning the shutter, etc., becomes difficult.

[0022] By fulfilling the above-mentioned configuration and inequalities, a zoom lens L0 with reduced size, high optical performance and high image stabilization performance can be achieved, while simultaneously reducing the size and weight as well as the range of motion of the IS image stabilization unit.

[0023] The lower bound of inequality (1) can be set to 1.93, 2.17, or 2.35, and the upper bound of inequality (1) can be set to 3.58, 3.28, or 3.05. The lower bound of inequality (2) can be set to 0.20, 0.30, or 0.55, and the upper bound of inequality (2) can be set to 1.55, 1.29, or 1.15. Inequality (2) can be replaced by the following inequality (2a): 0.05≤BFw / fw≤1.29

[0024] The zoom lens L0 according to each example can further have the following configuration: In the zoom lens L0 according to each example, the first lens L1 is fixed relative to the image plane IP during zooming. The weight of the first lens unit L1 likely increases due to the large outer diameter of the lens in the first lens unit L1. Thus, the fixed first lens unit L1 during zooming enables fast and quiet zooming. Furthermore, the fixed first lens unit L1 during zooming prevents tilting of the first lens unit L1 during zooming and improves optical performance.

[0025] In the zoom lens L0 according to each example, the first lens unit L1, in order from the object side to the image side, can comprise two meniscus lenses (a first meniscus lens and a second meniscus lens) that have a negative refractive power and are convex towards the object side. This allows the zoom lens L0 to achieve high zoom magnification on the wide-angle side and satisfactorily correct off-axis aberrations such as field curvature.

[0026] In the zoom lens L0 according to each example, the first lens unit L1 can comprise two or more lenses, including a negative lens and a positive lens. This allows for satisfactory correction of aberrations. By satisfactorily correcting off-axis aberrations such as chromatic aberration and field curvature that occur in the first lens unit L1, which remains stationary during zooming, the number of lenses required for aberration correction in the second lens unit L2, the intermediate assembly LM, and the rear lens unit Lr, which move during zooming, can be reduced. This allows for a reduction in the size and weight of the lens units that move during zooming. A positive lens, particularly for the correction of chromatic aberrations, can be positioned closest to the image plane in the first lens unit L1.

[0027] In the zoom lens L0 according to each example, the second lens unit L2 can encompass a maximum aperture SP, since it is possible to reduce the size and weight of the moving lens units, such as the lenses in the second lens unit L2, which are located near the maximum aperture SP, and the intermediate lens group LM, which comprises the Nth intermediate lens unit. This allows this configuration to provide several lenses necessary for aberration correction while simultaneously reducing the load on the actuator that drives the moving lens units during zooming, thus achieving good aberration performance with increased zoom magnification.

[0028] In the zoom lens L0 according to each example, the Nth intermediate lens unit can comprise three or fewer lenses. This configuration can eliminate the high weight of the Nth intermediate lens unit, which includes an image stabilization mechanism, and thereby reduce the load on the actuator that controls the Nth intermediate lens unit during zooming.

[0029] In the zoom lens L0 according to each example, the second lens unit L2 with positive refractive power can comprise an aspherical lens with a lens surface shape whose refractive power decreases from the optical axis towards the surroundings. This allows the overall length of the zoom lens L0 to be reduced and spherical aberrations, coma, and other aberrations, which occur particularly in the telephoto range, to be satisfactorily corrected.

[0030] In the zoom lens L0 according to each example, the entire second lens unit L2, the intermediate group LM, and the rear lens unit Lr can move from the wide-angle end to the telephoto end toward the subject during the zoom operation. This configuration enables high zoom magnification while effectively suppressing aberration fluctuations during the zoom process. The number of lens units moving during the zoom operation can be four or fewer. This prevents the overall size of the zoom lens from increasing when each moving lens is driven by an electrical actuator.

[0031] In the zoom lens L0 according to each example, the rear lens Lr can have a negative refractive power and be located on the image side and adjacent to the second lens L2 and the intermediate assembly LM, each of which has a positive refractive power. Such a telephoto power arrangement can reduce the overall length of the zoom lens L0.

[0032] In the zoom lens L0 according to each example, an object-side surface of a lens located closest to the object in the rear lens unit Lr can have a convex shape towards the object. This configuration can suppress fluctuations of spherical aberration that occur during zooming. The lens element located closest to the object in the rear lens unit Lr can have a meniscus shape with negative refractive power and a convex shape towards the object. The rear lens unit Lr can be used as a focusing lens unit that moves towards the image plane during focusing from infinity to a close distance. This configuration can achieve focusing with suppressed fluctuations of aberrations such as spherical aberration and field curvature.

[0033] A final lens unit Lk with positive refractive power, which remains stationary during zooming, can be positioned closest to the image plane in the zoom lens L0, as in any example. In a case where the zoom lens L0 is used as an electric zoom lens for a camera with interchangeable lenses, the robustness of the zoom lens L0 can be improved by positioning a fixed lens unit closest to the image plane to prevent direct external access to the moving lens unit. A lens unit with positive refractive power positioned closest to the image plane can reduce the angle of incidence of an off-axis beam relative to the image sensor mounted on the image plane IP. This can prevent vignetting that occurs across the image area.

[0034] The zoom lens L0 according to each example can satisfy at least one of the following inequalities (3) to (8): 0,9≤fN / (−f1)≤4,5 0,40≤(1−βist)×βisrt≤1,45 0,4≤|MN / M2|≤1,2 3,5≤TTLw / fw≤8,9 1,0≤fis / f2≤4,5 0,54≤f2 / (−f1)≤2,35

[0035] In inequalities (3) to (8), f2 is the focal length of the second lens unit L2, fN is the focal length of the Nth intermediate lens unit, and βist is the lateral magnification of the image stabilization (shifting) unit IS at the telephoto end. βist is the lateral magnification of an optical system that includes all lenses located closer to the image plane than the image stabilization unit IS at the telephoto end. M2 is the amount of movement of the second lens unit L2 during zooming from the wide-angle to the telephoto end, and MN is the amount of movement of the Nth intermediate lens unit during zooming from the wide-angle to the telephoto end. The amount of movement of a lens unit is the difference between its position at the wide-angle end and its position at the telephoto end and does not include any reciprocal movement.It is positive if the lens unit is positioned closer to the image plane at the telephoto end than at the wide-angle end, and negative if it is positioned closer to the object at the telephoto end than at the wide-angle end. TTLw is a total optical length calculated by adding the air equivalent distance (BFw) on the optical axis from a lens of the zoom lens L0 closest to the image plane to the image plane at the wide-angle end, and the distance on the optical axis from a lens of the zoom lens L0 closest to the object to a lens of the zoom lens L0 closest to the image plane at the wide-angle end.

[0036] Inequality (3) defines a suitable relationship between the focal length of the first lens L1 and the focal length of the Nth intermediate lens. If fN / (-f1) exceeds the upper limit of inequality (3), the power of the Nth intermediate lens unit is reduced, and the range of motion of the Nth intermediate lens unit during zooming increases. Furthermore, if the power of the first lens unit L1 increases, it becomes difficult to properly correct off-axis aberrations such as field curvature. If fN / (-f1) exceeds the lower limit of inequality (3), the power of the Nth intermediate lens unit increases, and it becomes difficult to properly correct aberrations. Additionally, if the power of the first lens unit L1 is reduced, the range of motion of the moving lens unit during zooming and the size of the zoom lens L0 increase.

[0037] The lower bound of inequality (3) can be set to 1.32, 1.61 or 1.80, and the upper bound of inequality (3) can be set to 3.58, 3.28 or 3.05.

[0038] Inequality (4) defines a suitable range for the image shift sensitivity TS of the image stabilization unit IS in the telephoto range. The image shift sensitivity TS is a ratio (TS = ΔI / ΔL) between a movement quantity ΔL of the image stabilization unit IS in a direction orthogonal to the optical axis and a movement quantity ΔI of the optical image (image position) on the image plane IP in a direction orthogonal to the optical axis. If (1-βist)×βisrt becomes larger than the upper limit of inequality (4), the performance of the image stabilization unit IS increases, and it becomes difficult to correct aberrations such as decentered coma during image stabilization, thus rendering the image stabilization performance insufficient.In a case where (1-βist)×βisrt becomes lower than the lower bound of inequality (4), the image shift sensitivity TS of the image stabilization unit IS is reduced, and the amount of movement of the image stabilization unit IS for image stabilization, and thus the size of the image stabilization mechanism, increases.

[0039] The lower bound of inequality (4) can be set to 0.55, 0.60 or 0.67, and the upper bound of inequality (4) can be set to 1.21, 1.10 or 0.97.

[0040] Inequality (5) defines a suitable relationship between the motion of the second lens L2 and the motion of the Nth intermediate lens during zooming from the wide-angle end to the telephoto end. If |MN / M2| is greater than the upper limit of inequality (5), the motion of the Nth intermediate lens unit increases during zooming, and the suppression of fluctuations such as field curvature becomes insufficient. If |MN / M2| is less than the lower limit of inequality (5), the motion of the Nth intermediate lens unit cannot be adequately controlled for high zoom magnification during zooming, or the motion of the second lens unit L2 increases during zooming.

[0041] The lower bound of inequality (5) can be set to 0.54, 0.61 or 0.65, and the upper bound of inequality (5) can be set to 0.95, 0.87 or 0.82.

[0042] Inequality (6) defines a suitable relationship between the total optical length of the zoom lens L0 at the wide-angle end and the focal length of the entire zoom lens system L0 at the wide-angle end. If TTLw / fw exceeds the upper limit of inequality (6), the size of the zoom lens L0 increases. If TTLw / fw falls below the lower limit of inequality (6), it becomes difficult to provide sufficient space for the lens arrangement to achieve adequate aberration correction.

[0043] The lower bound of inequality (6) can be set to 3.87, 4.36 or 4.75, and the upper bound of inequality (6) can be set to 8.23, 7.88 or 7.30.

[0044] Inequality (7) defines a suitable relationship between the focal length of the second lens unit L2 and the focal length of the image stabilization unit IS. If fis / f2 becomes larger than the upper limit of inequality (7), the performance of the image stabilization unit IS is reduced, and the range of motion of the image stabilization unit IS for image stabilization, and thus the size of the image stabilization mechanism, increases. Furthermore, in a case where the performance of the second lens unit L2 increases, it becomes difficult to satisfactorily correct axial aberrations such as spherical aberrations. In a case where fis / f2 becomes smaller than the lower limit of inequality (7), the performance of the image stabilization unit IS increases, it becomes difficult to correct aberrations such as decentered coma during image stabilization, and insufficient image stabilization performance is achieved.Furthermore, if the power of the second lens unit L2 is reduced, the range of motion of the second lens unit L2 during zooming and thus the size of the zoom lens L0 also increase.

[0045] The lower bound of inequality (7) can be set to 1.50 or 2.00, and the upper bound of inequality (7) can be set to 3.50, 2.96 or 2.75.

[0046] Inequality (8) defines a suitable ratio between the focal lengths of the first lens L1 and the second lens L2. If f2 / (-f1) exceeds the upper limit of inequality (8), the power of the first lens L1 increases, and it becomes difficult to correct off-axis aberrations such as field curvature, which occur in the first lens L1 in the wide-angle region. Furthermore, if the power of the second lens L2 is reduced, it becomes difficult to obtain a suitable zoom factor. If f2 / (-f1) is less than the lower limit of inequality (8), the power of the first lens L1 is reduced, and its outer diameter increases in the wide-angle region. Additionally, if the power of the second lens L2 is increased, it becomes difficult to correct on-axis aberrations such as spherical aberrations.

[0047] The lower bound of inequality (8) can be set to 0.75, 0.85 or 0.90, and the upper bound of inequality (8) can be set to 1.90 or 1.50.

[0048] Next, the detailed configurations of the L0 zoom lenses are described according to Examples 1 to 6. Following Example 6, the numerical examples 1 to 6, which correspond to Examples 1 to 6, are illustrated. EXAMPLE 1

[0049] A zoom lens L0 according to Example 1 (numerical example 1), which is in Fig.As illustrated in Figure 1, the system comprises, in order from the object side to the image side, a first lens L1 with negative refractive power, a second lens L2 with positive refractive power which includes an aperture SP, a first intermediate lens unit Lmp1 with positive refractive power, a rear lens unit Lr with negative refractive power, and a final lens unit Lk with positive refractive power. The intermediate group LM includes the first intermediate lens unit Lmp1, and the Nth intermediate lens unit is the first intermediate lens unit Lmp1.

[0050] During zooming, the first lens L1 and the last lens Lk are fixed relative to the image plane IP. During zooming from the wide-angle end to the telephoto end, the entire second lens L2, the first intermediate lens Lmp1, and the rear lens Lr move monotonically towards the object side. During focusing from infinity to a close distance, the rear lens Lr moves towards the image side. The first intermediate lens unit Lmp1, which includes its element attached to the image plane, functions entirely as the image stabilization unit IS and moves in a direction orthogonal to the optical axis.

[0051] The first lens unit L1 comprises four lens elements, which, in order from the object side to the image side, include a first negative meniscus lens convex towards the object side, a second negative meniscus lens convex towards the object side, a biconcave negative lens, and a positive meniscus lens convex towards the object side. The second lens unit L2 comprises the aperture SP and three lens elements. More precisely, the second lens unit L2 comprises, in order from the object side to the image side, a biconvex positive lens with aspherical surfaces on both sides, the aperture SP, a biconcave negative lens, and a biconvex positive lens.

[0052] The first intermediate lens unit Lmp1 comprises, in order from the object side to the image side, a single lens element, which is a positive bonded lens formed by bonding together a negative meniscus lens, convex towards the object side, and a positive meniscus lens, also convex towards the object side. The rear lens unit Lr comprises two lens elements, in order from the object side to the image side, a negative meniscus lens, convex towards the object side, and a negative meniscus lens with aspheric surfaces on both sides, convex towards the image side. The last lens unit Lk comprises a single lens element, which is a positive meniscus lens, convex towards the image side.

[0053] The Fig. 2A, Fig. 2B and Fig.Figure 2C illustrates the longitudinal aberrations (spherical aberration, astigmatism, distortion, and chromatic aberration) of the L0 zoom lens, as shown in Numerical Example 1, at the wide-angle end in focus at infinity. In the spherical aberration diagram, Fno represents the f-stop. A solid line indicates the spherical aberration value for the d-line (wavelength 587.6 nm), and one alternating long and two short dashed lines indicate the spherical aberration value for the g-line (wavelength 435.8 nm). In the astigmatism diagram, a solid line S indicates the astigmatism value on a sagittal image plane, and a dashed line M indicates the astigmatism value on a meridional image plane. The distortion diagram illustrates the distortion value for the d-line. The chromatic aberration diagram illustrates the lateral chromatic aberration value for the g-line. ω is half the viewing angle (°).The above description of aberration representations also applies to the aberration representations of other numerical examples. EXAMPLE 2

[0054] A zoom lens L0 according to Example 2 (numerical example 2), which is in Fig. As illustrated in Figure 3, the system comprises, in order from the object side to the image side, a first lens L1 with negative refractive power, a second lens L2 with positive refractive power which includes an aperture SP, a first intermediate lens unit Lmp1 with positive refractive power, a first rear lens unit Lr1 with negative refractive power, a second rear lens unit Lr2 with negative refractive power, and a final lens unit Lk with positive refractive power. The intermediate group LM includes the first intermediate lens unit Lmp1, and the Nth intermediate lens unit is the first intermediate lens unit Lmp1.

[0055] During the zoom operation, the first lens L1 and the last lens Lk are fixed relative to the image plane IP. During the zoom operation from the wide-angle end to the telephoto end, the entire second lens L2, the first intermediate lens Lmp1, the first rear lens Lr1, and the second rear lens Lr2 move monotonically toward the object side. In this example, the rear lens unit is divided into two parts, the first rear lens unit Lr1 and the second rear lens unit Lr2, and during focusing from infinity to a short distance, the first rear lens unit Lr1 and the second rear lens unit Lr2 move along different loci toward the image side. The first intermediate lens unit Lmp1, whose element is closest to the image plane, fully incorporates the function of the image stabilization unit IS and moves in a direction orthogonal to the optical axis.

[0056] The first lens unit L1 comprises four lens elements, which, in order from the object side to the image side, include a first negative meniscus lens with an aspherical surface on the image side and a convex shape towards the object side, a second negative meniscus lens with a convex shape towards the object side, a biconcave negative lens, and a positive meniscus lens with a convex shape towards the object side. The second lens unit L2 comprises the aperture SP and four lens elements. More precisely, the second lens unit L2 comprises, in order from the object side to the image side, a biconvex positive lens with aspherical surfaces on both sides, a biconvex positive lens, a biconcave negative lens, the aperture SP, and a positive plano-convex lens with an aspherical surface on the image side and a convex surface towards the image side.

[0057] The first intermediate lens unit Lmp1 comprises a single lens element, which is a positive cemented lens formed by cementing together a negative meniscus lens with an object-side convex shape and a positive meniscus lens with an object-side convex shape, arranged in order from the object side to the image side. The first posterior lens unit Lr1 comprises a single lens element, which is a negative cemented lens formed by cementing together a biconvex positive lens and a biconcave negative lens, arranged in order from the object side to the image side. The second posterior lens unit Lr2 comprises a single lens element, which is a negative meniscus lens convex towards the image side. The final lens unit Lk comprises a single lens element, which is a positive meniscus lens convex towards the image side.

[0058] The Fig. 4A, Fig. 4B and Fig. Figure 4C illustrates the longitudinal aberration of the zoom lens L0 according to numerical example 2 at the wide-angle end in the focused state at infinity distance. EXAMPLE 3

[0059] A zoom lens L0 according to Example 3 (numerical example 3), which is in Fig. As illustrated in Figure 5, the system comprises, in order from the object side to the image side, a first lens unit L1 with negative refractive power, a second lens unit L2 with positive refractive power which includes an aperture SP, a first intermediate lens unit Lmp1 with positive refractive power, a rear lens unit Lr with negative refractive power, and a final lens unit Lk with positive refractive power. The intermediate group LM includes the first intermediate lens unit Lmp1, and the Nth intermediate lens unit is the first intermediate lens unit Lmp1.

[0060] During zooming, the first lens L1 and the last lens Lk are fixed relative to the image plane IP. During zooming from the wide-angle end to the telephoto end, the entire second lens L2, the first intermediate lens Lmp1, and the rear lens Lr move monotonically towards the object side. During focusing from infinity to a close distance, the rear lens Lr moves towards the image side. The cemented lens in the first intermediate lens unit Lmp1, located closest to the image plane, acts as the image stabilization unit IS, moving in a direction orthogonal to the optical axis.

[0061] The first lens unit L1 comprises four lens elements, which, in order from the object side to the image side, include a first negative meniscus lens convex towards the object side, a second negative meniscus lens convex towards the object side, a biconcave negative lens, and a positive meniscus lens convex towards the object side. The second lens unit L2 comprises the aperture SP and four lens elements. More precisely, the second lens unit L2 comprises, in order from the object side to the image side, a biconvex positive lens with aspherical surfaces on both sides, a negative meniscus lens convex towards the object side, the aperture SP, a biconcave negative lens, and a biconvex positive lens.

[0062] The first intermediate lens unit, Lmp1, comprises two lens elements: a biconvex positive lens and a positive cemented lens consisting of a biconvex positive lens and a biconcave negative lens cemented together. The rear lens unit, Lr, comprises two lens elements: a negative meniscus lens convex towards the object side and a negative meniscus lens convex towards the image side with aspherical surfaces on both sides. The last lens unit, Lk, comprises a lens element that is a biconvex positive lens.

[0063] The Fig. 6A, Fig. 6B and Fig. Figure 6C illustrates the longitudinal aberration of the zoom lens L0 according to numerical example 3 at the wide-angle end in the focused state at infinity distance. EXAMPLE 4

[0064] A zoom lens L0 according to Example 4 (numerical example 4), which is in Fig. As illustrated in Figure 7, the system comprises, in order from the object side to the image side, a first lens L1 with negative refractive power, a second lens L2 with positive refractive power which includes an aperture SP, a first intermediate lens unit Lmp1 with positive refractive power, a second intermediate lens unit Lmp2 with positive refractive power, a rear lens unit Lr with negative refractive power, and a final lens unit Lk with positive refractive power. The intermediate group LM comprises the first intermediate lens unit Lmp1 and the second intermediate lens unit Lmp2, and the Nth intermediate lens unit is the second intermediate lens unit Lmp2.

[0065] During zooming, the first lens L1 and the last lens Lk are fixed relative to the image plane IP. During zooming from the wide-angle end to the telephoto end, the entire second lens L2, the first intermediate lens Lmp1, the second intermediate lens Lmp2, and the rear lens Lr move monotonically towards the object side. During focusing from infinity to a short distance, the first intermediate lens unit Lmp1 moves towards the object side. The entire second intermediate lens unit Lmp2, including its element closest to the image plane, functions entirely as the image stabilization unit IS and moves in a direction orthogonal to the optical axis.

[0066] The first lens unit L1 comprises four lens elements, which, in order from the object side to the image side, include a first negative meniscus lens that is convex towards the object side, a second negative meniscus lens that is convex towards the object side and has an aspherical surface on the image side, a biconcave negative lens, and a positive meniscus lens that is convex towards the object side. The second lens unit L2 comprises the aperture SP and two lens elements. More precisely, the second lens unit L2 comprises, in order from the object side to the image side, a biconvex positive lens element with aspherical surfaces on both sides, a negative meniscus lens element that is convex towards the object side, and the aperture diaphragm SP.

[0067] The first intermediate lens unit Lmp1 comprises a single lens element, which is a positive cemented lens formed by bonding together a negative meniscus lens convex towards the object and a biconvex positive lens, arranged in that order from the object side to the image side. The second intermediate lens unit Lmp2 comprises a single lens element, which is a positive cemented lens formed by bonding together a positive biconvex lens and a negative biconcave lens, arranged in that order from the object side to the image side. The rear lens unit Lr comprises two lens elements, which, in that order from the object side to the image side, include a negative meniscus lens convex towards the object side and a negative meniscus lens convex towards the image side with aspherical surfaces on both sides.The last lens unit Lk comprises a single lens element, which is a biconvex positive lens.

[0068] The Fig. 8A, Fig. 8B and Fig. Figure 8C illustrates the longitudinal aberration of the zoom lens L0 according to numerical example 4 at the wide-angle end in the focused state at infinity distance. EXAMPLE 5

[0069] A zoom lens L0 according to Example 5 (numerical example 5), which is in Fig.As illustrated in Figure 9, the assembly comprises, in order from the object side to the image side, a first lens L1 with negative refractive power, a second lens L2 with positive refractive power which includes an aperture SP, a first intermediate lens unit Lmp1 with positive refractive power, a rear lens unit Lr with negative refractive power, and a final lens unit Lk with positive refractive power. The intermediate group LM includes the first intermediate lens unit Lmp1, and the Nth intermediate lens unit is the first intermediate lens unit Lmp1.

[0070] During zooming, the first lens L1 and the last lens Lk are fixed relative to the image plane IP. During zooming from wide-angle to telephoto, the entire second lens L2, the first intermediate lens Lmp1, and the rear lens Lr move monotonically towards the object side. During focusing from infinity to a short distance, the rear lens Lr moves towards the image side. The first intermediate lens unit Lmp1, comprising its element closest to the image plane, functions entirely as the image stabilization unit IS and moves in a direction orthogonal to the optical axis.

[0071] The first lens unit L1 comprises four lens elements, which, in order from the object side to the image side, include a first negative meniscus lens convex towards the object side, a second negative meniscus lens convex towards the object side, a biconcave negative lens, and a positive meniscus lens convex towards the object side. The second lens unit L2 comprises the aperture SP and three lens elements. More precisely, the second lens unit L2 comprises, in order from the object side to the image side, a biconvex positive lens with aspherical surfaces on both sides, a negative meniscus lens convex towards the object side, the aperture SP, and a positive bonded lens formed by bonding together a negative meniscus lens convex towards the object side and a biconvex positive lens.

[0072] The first intermediate lens unit Lmp1 comprises a single lens element, which is a positive cemented lens formed by bonding together a biconvex positive lens and a biconcave negative lens, arranged in that order from the object side to the image side. The rear lens unit Lr comprises two lens elements, which, in that order from the object side to the image side, include a negative meniscus lens convex towards the object side and a negative meniscus lens convex towards the image side, having aspheric surfaces on both sides. The last lens unit Lk comprises a single lens element, which is a positive meniscus lens convex towards the image side.

[0073] The Fig. 10A, Fig. 10B and Fig.Figure 10C illustrates the longitudinal aberration of the zoom lens L0 according to numerical example 5 at the wide-angle end in the focused state at infinity distance. EXAMPLE 6

[0074] A zoom lens L0 according to Example 6 (numerical example 6), which is in Fig. As illustrated in Figure 11, the assembly comprises, in order from the object side to the image side, a first lens L1 with negative refractive power, a second lens L2 with positive refractive power which includes an aperture SP, a first intermediate lens Lmp1 with positive refractive power, and a rear lens Lr with negative refractive power. The zoom lens L0 according to this example has no last lens. The intermediate assembly LM comprises the first intermediate lens unit Lmp1, and the Nth intermediate lens unit is the first intermediate lens unit Lmp1.

[0075] During zooming, the first lens L1 is fixed relative to the image plane IP. During zooming from the wide-angle end to the telephoto end, the entire second lens L2, the first intermediate lens Lmp1, and the rear lens Lr move monotonically towards the object side. During focusing from infinity to a short distance, the rear lens Lr moves towards the image side. The first intermediate lens unit Lmp1, which includes its element attached to the image plane, functions entirely as the image stabilization unit IS and moves in a direction orthogonal to the optical axis.

[0076] The first lens unit L1 comprises four lens elements, which, in order from the object side to the image side, include a first negative meniscus lens convex towards the object side, a second negative meniscus lens convex towards the object side, a biconcave negative lens, and a positive meniscus lens convex towards the object side. The second lens unit L2 comprises the aperture SP and three lens elements. The second lens unit L2 comprises, in order from the object side to the image side, a biconvex positive lens with aspherical surfaces on both sides, the aperture SP, a negative meniscus lens convex towards the object side, and a positive meniscus lens convex towards the image side.

[0077] The first intermediate lens unit Lmp1 comprises a single lens element, which is a positive cemented lens formed by bonding together a negative meniscus lens convex towards the object side and a positive meniscus lens convex towards the image side, arranged in that order from the object side to the image side. The rear lens unit Lr comprises two lens elements, which, in that order from the object side to the image side, include a negative cemented meniscus lens formed by bonding together a biconvex positive lens and a biconcave negative lens, and a negative meniscus lens, which is a plastic lens with aspherical surfaces on both sides and convex towards the image side.

[0078] The Fig. 12A, Fig. 12B and Fig.Figure 12C illustrates the longitudinal aberration of the zoom lens L0 according to numerical example 6 at the wide-angle end in the focused state at infinity distance.

[0079] Numerical examples 1 to 6 are illustrated below. In the surface data for each numerical example, a surface number i indicates the sequence of optical surfaces, counting from the object face; r represents the radius of curvature of the i-th surface; and d (mm) indicates the distance (distance along the optical axis) between the i-th and the (i+1)-th surface. nd indicates a refractive index for the d-line (587.6 nm) of an optical material between the i-th and the (i+1)-th surface; and vd indicates an Abbe number of an optical material based on the d-line. The Abbe number vd based on the d-line is expressed as follows: vd=(Nd−1) / (NF−NC) where Nd, NF and NC are the refractive indices for the d-line, the F-line (486.1 nm) and the C-line (656.3 nm) respectively.

[0080] The focal length (mm), aperture value, and half the angle of view (°) have values ​​when the lens is focused at infinity. The back focus (BF) is the air-equivalent distance along the optical axis from the surface of the lens closest to the image plane (end face) of a zoom lens to the image plane. The total optical length is the distance along the optical axis from the surface of the lens closest to the object to the end face of the zoom lens, plus the back focus (BF).

[0081] An asterisk (*) next to a surface indicates that the lens surface is aspherical. The aspherical shape is expressed as follows: x=(h2 / R) / [1+{1−(1+K)(h / R)2}1 / 2]+A4×h4+A6×h6+A8×h8+A10×h10+A12×h12 where x is the displacement from a vertex of the surface in the direction of the optical axis, h is the height from the optical axis in a direction orthogonal to the optical axis, R is the paraxial radius of curvature, K is the conic constant, and A4, A6, A8, ... are the aspheric coefficients of each order. “e±XX” in the conic constant and the aspheric coefficients means “× 10 ±XX “ NUMERICAL EXAMPLE 1 UNIT: mm SURFACE DATA Surface No. r d and vd 1 48,788 2,00 1,80400 46,5 2 21,860 5,64 3 57,046 1,74 1,72916 54,7 4 23,770 7,35 5 -54,146 1,36 1,49700 81,7 6 170,908 0,61 7 44,960 3,16 1,90110 27,1 8 171,520 (Variable) 9* 23,768 6,51 1,58313 59,4 10* -38,363 4,07 11 (SP) ∞ 2,16 12 -64,016 0,90 1,73800 32,3 13 30,388 2,63 14 108,662 4,69 1,49700 81,7 15 -20,020 (Variable) 16 26,181 1,05 1,72047 34,7 17 18,469 3,58 1,49700 81,7 18 118,593 (Variable) 19 24,431 1,20 1,80400 46,5 20 16,770 7,15 21* -34,605 1,70 1,58313 59,4 22* -990,655 (Variable) 23 -168,002 7,73 1,67300 38,1 24 -33,001 13,50 Image plane ∞ ASPHERICAL DATA 9. Surface K = 0.00000e+00 A 4=-1.65323e-05 A 6=-3.34095e-08 A 8= 1.98795e-10 A10=-3.25473e-12 10. Surface K = 0.00000e+00 A 4= 1.36050e-05 A 6=-3.75284e-08 A 8= 2.12565e-10 A10=-3.23024e-12 21. Surface K = 0.00000e+00 A 4=-1.18164e-04 A 6= 2.73264e-07 A 8=-2.67312e-09 A10= 8.38987e-12 22. Surface K = 0.00000e+00 A 4=-9.89605e-05 A 6= 3.76549e-07 A 8=-1.73256e-09 A10= 4.12838e-12 VARIOUS DATA Zoom ratio 2.35 WIDE ANGLE CENTER TELE Focal length 20,60 31,67 48,50 Fno 4,08 4,08 4,12 Half angle of view (°) 41,81 32,43 23,57 Image height 18,43 20,12 21,16 Optical total length 114,20 114,20 114,20 BF 13,50 13,50 13,50 d8 27,74 14,95 2,17 d15 1,55 5,01 9,40 d18 2,45 2,55 7,77 d22 3,74 12,97 16,15 LENS UNIT DATA Lens unit Starting surface Focal length 1 1 -28,76 2 9 31,90 3 16 85,78 4 19 -31,75 5 23 59,65 NUMERICAL EXAMPLE 2 UNIT: mm SURFACE DATA Surface No. r d and vd 1 51,999 1,50 1,76450 49,1 2* 21,707 7,13 3 89,782 1,50 1,72916 54,7 4 33,747 6,96 5 -46,940 1,00 1,43875 94,7 6 481,579 0,15 7 48,882 3,08 1,90110 27,1 8 172,633 (Variable) 9* 25,608 6,60 1,58313 59,4 10* -45,641 1,90 11 743,905 3,43 1,59282 68,6 12 -32,695 0,78 13 -33,591 0,90 1,67300 38,3 14 27,082 3,62 15 (SP) ∞ 1,50 16 ∞ 4,76 1,49700 81,7 17* -22,237 (Variable) 18 39,639 0,90 1,85478 24,8 19 23,350 2,82 1,72916 54,7 20 153,745 (Variable) 21 38,314 1,79 1,92286 20,9 22 -299,310 0,90 1,87400 35,3 23 18,641 (Variable) 24 -19,345 1,00 1,85478 24,8 25 -25,976 (Variable) 26 -339,660 8,22 1,59282 68,6 27 -33,588 21,75 Image plane ∞ ASPHERICAL DATA 2. Surface K = 0.00000e+00 A 4= 1.00150e-07 A 6=-7.95946e-10 A 8=-4.40810e-12 A10=-4.57871e-15 9. Surface K = 0.00000e+00 A 4=-8.41099e-06 A 6=-1.53412e-09 A 8= 1.04408e-10 10. Surface area K = 0.00000e+00 A 4= 2.26558e-05 A 6=-1.07080e-08 A 8= 2.06328e-10 A10=-1.62470e-13 17. Surface K = 0.00000e+00 A 4=-4.76412e-06 A 6= 2.31973e-09 A 8=-1.06887e-10 VARIOUS DATA Zoom ratio 2.83 WIDE ANGLE MEDIUM TELE Focal length 20,60 34,01 58,20 Fno 4,08 4.08 4,12 Half angle of view (°) 41,80 30,66 19,84 Image height 18,42 20,16 21,00 Optical total length 130,00 130,00 130,00 BF 21,75 21,75 21,75 d8 36,95 19,22 1,50 d17 1,50 3,79 8,83 d20 1,40 1,50 6,77 d23 5,76 9,23 12,56 d25 2,19 14,05 18,14 LENS DATA Lens unit Home screen Focal length 1 1 -32,14 2 9 33,97 3 18 85,67 4 21 -47,52 5 24 -95,28 6 26 62,25 NUMERICAL EXAMPLE 3 UNIT: mm SURFACE DATA Surface No. r d and vd 1 38,683 2,00 1,80400 46,5 2 20,802 6,54 3 73,788 1,55 1,72916 54,7 4 25,722 6,47 5 -62,919 1,32 1,49700 81,7 6 103,148 0,92 7 42,445 2,95 1,90110 27,1 8 126,306 (Variable) 9* 22,231 6,18 1,58313 59,4 10* -45,825 1,29 11 79,640 0,90 1,84666 23,8 12 47,541 1,81 13 (SP) ∞ 4,04 14 -28,316 0,90 1,61340 44,3 15 28,571 0,57 16 37,913 5,48 1,49700 81,7 17 -19,922 (Variable) 18 90,838 1,34 1,59282 68,6 19 -4278,940 1,00 20 35,624 3,49 1,49700 81,7 21 -35,409 0,90 1,51742 52,4 22 292,259 (Variable) 23 24,507 0,90 1,51742 52,4 24 15,568 7,77 25* -29,839 1,85 1,58313 59,4 26* -999,757 (Variable) 27 365,125 8,79 1,59282 68,6 28 -35,559 15,83 Image plane ∞ ASPHERICAL DATA 9. Surface K = 0.00000e+00 A 4=-8.96326e-06 A 6=-8.23607e-09 A 8= 9.36610e-11 A10= 9.97060e-13 10. Surface K = 0.00000e+00 A 4= 1.59324e-05 A 6=-9.97104e-09 A 8= 1.64378e-10 A10= 7.44975e-13 25. Surface K = 0.00000e+00 A 4=-8.00313e-05 A 6= 3.83989e-07 A 8=-1.68600e-09 A10=-5.87468e-12 A12= 4.26853e-15 26. Surface K = 0.00000e+00 A 4=-6.80403e-05 A 6= 4.28544e-07 A 8=-2.28917e-09 A10= 3.59189e-12 VARIOUS DATA Zoom ratio 2.35 WIDE ANGLE CENTER TELE Focal length 20,60 31,74 48,50 Fno 4,08 4.08 4,12 Half angle of view (°) 41,59 32,25 23,64 Image height 18,28 20,03 21,23 Optical total length 119,00 119,00 119,00 BF 15,83 15,83 15,83 d8 28,85 14,93 1,00 d17 1,20 4,42 9,09 d22 1,20 3,06 11,05 d26 2,96 11,81 13,07 LENS UNIT DATA Lens unit Starting surface Focal length 1 1 -28,94 2 9 36,66 3 18 54,76 4 23 -31,12 5 27 55,11 NUMBER EXAMPLE 4 UNIT: mm SURFACE DATA Surface No. r d and vd 1 57,022 1,80 1,69680 55,5 2 20,997 8,21 3 59,665 2,00 1,58313 59,4 4* 20,341 8,28 5 -73,192 1,32 1,49700 81,7 6 71,955 2,32 7 63,529 3,14 1,85478 24,8 8 1232,658 (Variable) 9* 17,150 5,55 1,58313 59,4 10* -114,655 1,84 11 30,561 0,90 1,95375 32,3 12 16,319 2,84 13 (SP) ∞ (Variable) 14 20,477 1,03 1,85025 30,1 15 15,969 5,09 1,43875 94,7 16 -39,822 (Variable) 17 33,337 2,50 1,80400 46,5 18 -66,497 0,90 1,67300 38,3 19 68,546 (Variable) 20 42,517 0,80 1,77250 49,6 21 17,124 5,72 22* -63,079 1,50 1,76450 49,1 23* -790,654 (Variable) 24 9305,694 9,76 1,49700 81,5 25 -30,835 12,50 Image plane ∞ ASPHERICAL DATA 4. Surface K = 0.00000e+00 A 4=-1.29206e-05 A 6=-3.33436e-08 A 8= 4.08273e-11 A10=-2.59124e-13 9. Surface K = 0.00000e+00 A 4=-1.87286e-05 A 6=-7.74645e-08 A 8= 3.20153e-10 A10=-2.29951e-12 10. Surface K = 0.00000e+00 A 4= 9.75513e-06 A 6=-6.27042e-08 A 8= 5.60291e-10 A10=-2.83944e-12 22. Surface K = 0.00000e+00 A 4=-2.70692e-04 A 6= 9.74607e-07 A 8=-6.71740e-09 A10=-9.42909e-12 23. Surface K = 0.00000e+00 A 4=-2.31475e-04 A 6= 1.38855e-06 A 8=-8.90312e-09 A10= 2.93218e-11 VARIOUS DATA Zoom ratio 2.06 WIDE ANGLE CENTER TELE Focal length 16,48 22,07 33,95 Fno 4,08 4,08 4,12 Half angle of view (°) 48,69 41,99 32,09 Image height 18,75 19,87 21,28 Optical total length 118,00 118,00 118,00 BF 12,50 12,50 12,50 d8 25,19 14,69 4,18 d13 8,64 11,91 7,97 d16 2,29 1,65 9,38 d19 2,10 3,10 2,52 d23 1,80 8,67 15,96 LENS UNIT DATA Lens unit Starting surface Focal length 1 1 -23,80 2 9 55,15 3 14 37,77 4 17 59,99 5 20 -25,45 6 24 61,86 NUMBER EXAMPLE 5 UNIT: mm SURFACE DATA Surface No. r d and vd 1 46,953 2,00 1,80400 46,5 2 21,356 5,35 3 42,819 1,25 1,61800 63,4 4 22,934 7,93 5 -58,865 1,19 1,49700 81,7 6 65,541 0,31 7 38,855 3,27 1,90110 27,1 8 104,133 (Variable) 9* 29,845 4,56 1,58313 59,4 10* -44,171 3,70 11 446,638 0,90 1,76182 26,5 12 53,635 3,75 13 (SP) ∞ 3,91 14 800,000 0,85 1,61340 44,3 15 25,168 6,12 1,49700 81,7 16 -24,238 (Variable) 17 32,742 4,13 1,49700 81,7 18 -32,972 1,05 1,51742 52,4 19 191,981 (Variable) 20 23,012 0,90 1,51633 64,1 21 14,870 7,20 22* -26,367 2,00 1,58313 59,4 23* -300.000 (Variable) 24 -322.629 7,53 1,65160 58,5 25 -34,000 13,50 Image plane ∞ ASPHERICAL DATA 9. Surface K = 0.00000e+00 A 4=-1.22200e-05 A 6=-1.30528e-08 A 8= 1.66705e-10 A10= 1.61469e-14 10. Surface K = 0.00000e+00 A 4= 9.41880e-06 A 6=-1.21827e-08 A 8= 1.93208e-10 22. Surface area K = 0.00000e+00 A 4 = -6.57431e-05 A 6 = 1.62758e-07 A 8 = 1.15618e-09 A10=-8.17630e-11 A12= 4.61761e-13 23. Surface K = 0.00000e+00 A 4=-5.36868e-05 A 6= 3.36296e-07 A 8=-3.43301e-09 A10= 1.01095e-11 VARIOUS DATA Zoom ratio 2.35 WIDE ANGLE CENTER TELE Focal length 20,60 31,77 48,50 Fno 4,08 4,08 4,12 Half angle of view (°) 41,54 32,30 23,66 Image height 18,25 20,09 21,25 Optical total length 116,79 116,79 116,79 BF 13,50 13,50 13,50 d8 27,43 14,43 1,43 d16 1,95 5,56 10,42 d19 2,69 3,09 8,72 d23 3,33 12,32 14,83 LENS UNIT DATA Lens unit Home screen Focal length 1 1 -28,28 2 9 32,51 3 17 83,12 4 20 -29,98 5 24 57,73 NUMBER EXAMPLE 6 UNIT: mm SURFACE DATA Surface No. r d and vd 1 33,149 1,50 1,95375 32,3 2 20,747 6,16 3 37,514 2,20 1,91082 35,2 4 20,517 7,76 5 -86,146 1,00 1,49700 81,7 6 44,315 1,58 7 34,512 3,58 1,85478 24,8 8 164,815 (Variable) 9* 17,447 6,60 1,58313 59,4 10* -35,367 2,08 11 (SP) ∞ 1,50 12 46,292 0,90 1,85451 25,2 13 16,328 2,07 14 -16,613 1,47 1,49700 81,7 15 -12,326 (Variable) 16 21,750 1,20 1,73800 32,3 17 15,280 2,28 1,49700 81,7 18 89,083 (Variable) 19 75,588 3,00 1,84666 23,9 20 -54,732 0,90 1,95375 32,3 21 47,079 5,67 22* -40,258 2,50 1,53504 55,7 23* -90,102 (Variable) Image plane ∞ ASPHERICAL DATA 9. Surface K = 0.00000e+00 A 4=-4.03996e-05 A 6=-1.61494e-07 A 8=-1.09460e-09 A10=-1.16939e-11 10. Surface K = 0.00000e+00 A 4= 2.15083e-05 A 6=-1.76542e-07 A 8=-1.96137e-09 A10= 3.48352e-12 22. Surface K = 0.00000e+00 A 4=-8.94279e-05 A 6=-8.41145e-07 A 8= 4.86754e-09 23. Surface K = 0.00000e+00 A 4=-8.02127e-05 A 6=-3.42404e-07 A 8= 2.28946e-09 A10=-6.59050e-13 VARIOUS DATA Zoom ratio 2.35 WIDE ANGLE CENTER TELE Focal length 20,60 31,82 48,50 Fno 3,61 4,69 5,83 Half angle of view (°) 42,64 32,68 23,77 Image height 18,97 20,41 21,36 Optical total length 99,74 99,74 99,74 BF 14,49 25,65 29,35 d8 25,32 13,41 1,50 d15 1,50 5,23 8,27 d18 4,48 1,50 6,68 d23 14,49 25,65 29,35 LENS UNIT DATA Lens unit Starting surface Focal length 1 1 -31,31 2 9 31,46 3 16 75,54 4 19 -55,82

[0082] Table 1 summarizes the values ​​of inequalities (1) to (8) in numerical examples 1 to 6. The zoom lens according to each numerical example satisfies all inequalities (1) to (8). ex.1 ex.2 ex.3 ex.4 ex.5 ex.6 fw 20.60 20.60 20.60 16.48 20.60 20.60 TTLw 114.20 130.00 119.00 118.00 116.79 99.74 BFw 13.50 21.75 15.83 12.50 13.50 14.49 f1 -28.76 -32.14 -28.94 -23.80 -28.28 -31.31 f2 31.90 33.97 36.66 55.15 32.51 31.46 fN 85.78 85.67 54.76 59.99 83.12 75.54 F# 85.78 85.67 85.51 59.99 83.12 75.54 β is 0.59 0.58 0.55 0.61 0.57 0.51 β isrt 1.81 2.08 1.72 2.14 1.81 1.60 M2 -25.57 -35.45 -27.85 -21.01 -26.00 -23.82 MN -17.72 -28.12 -19.96 -14.59 -17.53 -17.05 (1) fis / (-f1) 2.98 2.67 2.95 2.52 2.94 2.41 (2) BFw / fw 0.66 1.06 0.77 0.76 0.66 0.70 (3) fN / (-f1) 2.98 2.67 1.50 2.52 2.94 2.41 (4) (1- β is) × β isrt 0.75 0.88 0.77 0.84 0.77 0.78 (5) |MN / M2| 0.69 0.79 0.72 0.69 0.67 0.72 (6) TTLw / fw 5.54 6.31 5.78 7.16 5.67 4.84 (7) fis / T2 2.69 2.52 2.33 1.09 2.56 2.40 (8) f2 / (-f1) 1.11 1.06 1.27 2.32 1.15 1.00 IMAGE RECORDING DEVICE

[0083] Fig.Figure 13 illustrates a digital still camera (image-capturing device) that uses a zoom lens L0 according to one of Examples 1 to 6 as its imaging optical system. Reference numeral 10 denotes a camera body, and reference numeral 11 denotes an imaging optical system 11 that uses one of the zoom lenses L0 according to Examples 1 to 6. Reference numeral 12 denotes an image sensor (photoelectric converter element), such as a CCD sensor or a CMOS sensor, that is built into the camera body 10 and configured to photoelectrically convert an optical image produced by the optical imaging system 11 (or capture the object image through the zoom lens). The camera body 10 can be a single-lens reflex camera with a fast-acting mirror or a mirrorless camera without a fast-acting mirror.

[0084] The zoom lens L0 according to each example, when applied to an image-capturing device such as a digital still camera, can provide an image-capturing device with a reduced size.

[0085] An imaging system (e.g., a surveillance camera system) can include the zoom lens L0 according to any example and a control unit configured to control the zoom lens. In this case, the control unit controls a lens unit, a focusing lens unit, and the image stabilization unit IS, which are movable during zooming, focusing, and image stabilization. The control unit may not be integrated into the zoom lens L0 but may be separate from the zoom lens L0 to remotely control it.

[0086] Although the disclosure has described exemplary embodiments, it is understood that some embodiments are not limited to the disclosed embodiments.

[0087] Each example according to the revelation can provide a lens that reduces the size and can satisfactorily drive a sliding unit. QUOTES INCLUDED IN THE DESCRIPTION

[0000] This list of documents cited by the applicant was automatically generated and is included solely for the reader's convenience. The list is not part of the German patent or utility model application. The DPMA accepts no liability for any errors or omissions. Cited patent literature

[0000] JP 2021-196449

[0002]

Claims

A zoom lens (L0) comprising, in order from the object side to the image side: a first lens unit (L1) with negative refractive power; a second lens unit (L2); one or more intermediate lenses (LM); and a rear lens unit (LR), characterized in that at least the second lens and the one or more intermediate lenses move during a zoom operation and the distance between adjacent lenses changes, wherein the one or more intermediate lens units comprise an Nth intermediate lens unit located closest to an image plane, and the Nth intermediate lens unit includes a displacement unit (IS) with positive refractive power, located closest to the image plane and movable in a direction orthogonal to an optical axis of the zoom lens, and wherein the following inequalities are satisfied: 1.8 ≤ fs / ( − f1 ) ≤ 4.8 0.05 ≤ BFw / fw ≤ 1.29 where f1 is a focal length of the first lens, fis is a focal length of the shifting unit, fw is a focal length of the zoom lens at the wide-angle end, and BFw is an air equivalent distance on the optical axis from a surface of the lens that is closest to the image plane of the zoom lens at the wide-angle end to the image plane. Zoom lens according to claim 1, characterized in that the shifting unit comprises two or more lenses. Zoom lens according to claim 1, characterized in that the second lens unit comprises two or more lens elements. Zoom lens according to one of claims 1 to 3, characterized in that the first lens is fixed during zooming. Zoom lens according to one of claims 1 to 4, characterized in that the second lens and the one or more intermediate lenses move from the wide-angle end to the telephoto end in the direction of an object during the zoom process. Zoom lens according to one of claims 1 to 5, characterized in that four or fewer lens units move during the zoom process. Zoom lens according to one of claims 1 to 6, characterized in that the second lens unit has a positive refractive power. Zoom lens according to one of claims 1 to 7, characterized in that the displacement unit comprises a positive lens and a negative lens. Zoom lens according to one of claims 1 to 8, characterized in that the displacement unit consists of a single lens element. Zoom lens according to one of claims 1 to 9, characterized in that the first lens unit comprises, in order from the object side to the image side, a first meniscus lens with negative refractive power, which is convex towards the object side, and a second meniscus lens with negative refractive power, which is convex towards the object side. Zoom lens according to one of claims 1 to 10, characterized in that the Nth intermediate lens unit comprises three or fewer lenses. Zoom lens according to one of claims 1 to 11, characterized in that the following inequality is satisfied: 0.9 ≤ fN / ( − f 1 ) ≤ 4.5 where fN is the focal length of the Nth intermediate lens. Zoom lens according to one of claims 1 to 12, characterized in that the following inequality is satisfied: 0.40 ≤ ( 1 − β is ) × β isrt ≤ 1.45 where βist is the lateral magnification of the shift unit at the telephoto end, and βistr is the lateral magnification of an optical system that includes all lenses that are closer to the image plane than the shift unit at the telephoto end. Zoom lens according to one of claims 1 to 13, characterized in that the following inequality is satisfied: 0.4 ≤ | MN / M 2 | ≤ 1.2 where M2 is a movement quantity of the second lens during the zoom process from the wide-angle end to the telephoto end, and MN is a movement quantity of the Nth intermediate lens unit during the zoom process. Zoom lens according to any one of claims 1 to 14, characterized in that the following inequality is satisfied: 3.5 ≤ TTLw / fw ≤ 8.9 where TTLw is a total optical length calculated by adding BFw to a distance on the optical axis from a surface of a lens of the zoom lens that is closest to an object to a surface that is closest to the image plane of the zoom lens at the wide-angle end. Zoom lens according to one of claims 1 to 15, characterized in that the following inequality is satisfied: 1.0 ≤ fs / f2 ≤ 4.5 where f2 is a focal length of the second lens. Zoom lens according to one of claims 1 to 16, characterized in that the following inequality is satisfied: 0.54 ≤ f 2 / ( − f 1 ) ≤ 2.35 where f2 is the focal length of the second lens. Zoom lens according to one of claims 1 to 17, characterized in that the rear lens unit has a negative refractive power. Zoom lens according to one of claims 1 to 18, characterized in that a last lens unit with positive refractive power, which does not move during the zoom process, is located closest to the image plane of the zoom lens. Zoom lens according to claim 1 or 3, characterized in that the following inequality is satisfied: 1.93 ≤ fis / ( − f 1 ) ≤ 4.

8. A zoom lens comprising, in order from the object side to the image side: a first lens unit (L1) with negative refractive power; a second lens unit (L2); one or more intermediate lenses (LM); and a rear lens unit (LR), characterized in that at least the second lens and the one or more intermediate lenses move during the zoom operation and each distance between adjacent lenses changes, and wherein the one or more intermediate lens units comprise an Nth intermediate lens unit arranged closest to an image plane, and the Nth intermediate lens unit has a displacement unit (IS) with positive refractive power attached, arranged closest to the image plane and movable in a direction orthogonal to an optical axis of the zoom lens. Image capture device (10), comprising: the zoom lens according to any one of claims 1 to 21; and an image sensor (12) configured to capture an object image through the zoom lens.

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