Zoom lens

Abstract

The utility model discloses a zoom lens. The zoom lens sequentially comprises a first lens group with negative focal power, a second lens group with positive focal power and a third lens group with negative focal power from an object side to an image side along an optical axis, air gaps are formed between the lenses in the first to third lens groups; by changing the positions of the second lens group and the third lens group on the optical axis, the zoom lens is switched between a wide-angle end state and a long-focus end state, and continuous zooming is realized. The maximum image height of the zoom lens is not changed in the zooming process. The zoom lens further comprises an optical filter located between the third lens group and the imaging surface of the lens. Half ImgH of the length of a diagonal line of an effective pixel area on an imaging surface of the zoom lens satisfies 5 mmlt; imgHlt, ImgHlt; when the zoom lens is in a wide-angle end state and a long-focus end state respectively, the change value T3 of the air interval between the third lens group and the optical filter on the optical axis and the change value f of the effective focal length of the zoom lens meet the sum of 0.5 lt. T3 / flt; 1.

Description

Technical Field

[0001] The present application relates to the field of optical elements, and more specifically, to a zoom lens. Background Art

[0002] With the development of telephoto lenses, conventional upright telephoto lenses and periscope telephoto lenses can no longer meet the needs of customers. In order to increase competitiveness, features such as large apertures, large image planes, internal focusing, and continuous zoom have become the common pursuit of major manufacturers for periscope lenses. However, limited by the size of mobile phones, the upgrade of the aperture and image plane of periscope lenses has gradually entered a bottleneck, and each mobile phone terminal focuses on the development of continuous zoom lenses.

[0003] How to ensure a larger effective pixel area and imaging quality while ensuring miniaturization, and effectively prevent problems such as crosstalk or vignetting is a technical problem that current zoom lenses need to solve. Therefore, those skilled in the art hope to provide a periscope telephoto lens that can achieve continuous zoom, which can have a wider focal length range compared to fixed-focus lenses and can also have good imaging quality, in order to meet the growing high demand for telephoto lenses in the market and provide more shooting options for photography enthusiasts. Summary of the Utility Model

[0004] The present application provides a zoom lens, which may sequentially include, along the optical axis from the object side to the image side: a first lens group with negative optical power; a second lens group with positive optical power; and a third lens group with negative optical power; there is an air gap between each lens in the first lens group to the third lens group; by changing the positions of the second lens group and the third lens group on the optical axis, the zoom lens is switched between the wide-angle end state and the telephoto end state to achieve continuous zoom; and the maximum image height of the zoom lens remains unchanged during the zoom process; the zoom lens further includes a filter located between the third lens group and the imaging plane of the zoom lens; and the zoom lens satisfies: 5mm < ImgH < 5.5mm, and 0.5 < △T3 / △f < 1, where ImgH is half of the diagonal length of the effective pixel area on the imaging plane of the zoom lens; △T3 is the change value of the air gap on the optical axis between the third lens group and the filter when the zoom lens is in the wide-angle end state and the telephoto end state respectively; △f is the change value of the effective focal length when the zoom lens is in the wide-angle end state and the telephoto end state respectively.

[0005] In one embodiment, the zoom lens satisfies: -3 < △f / ImgH < -1.

[0006] In one embodiment, the first lens group includes a first lens closest to the object side; when the distance TTL from the object side of the first lens to the imaging plane on the optical axis and the zoom lens are respectively in the wide-angle end state and the telephoto end state, the change value △tan(Semi-FOV) of the tangent function of the maximum half field of view of the zoom lens and the entrance pupil diameter EPD of the zoom lens satisfy: 0.5 <TTL×△tan(Semi-FOV) / EPD<0.7。

[0007] In one embodiment, the zoom lens further comprises a filter located between the third lens group and the imaging surface; when the zoom lens is in the wide-angle end state and the telephoto end state, respectively, a change value △tan(CRA) of the tangent function of the maximum incident angle of the principal ray of the zoom lens and a change value △T3 of the air gap between the third lens group and the filter on the optical axis satisfy: -0.2 <ImgH×△tan(CRA) / △T3<0。

[0008] In one embodiment, the distortion DISTi of the maximum field of view of the zoom lens in the wide-angle end state satisfies: 1.5%<|DISTi|<2.5%.

[0009] In one embodiment, the effective focal length F1 of the first lens group, the effective focal length F2 of the second lens group, and the effective focal length F3 of the third lens group satisfy: -6<(F1+F3) / F2<-3.

[0010] In one embodiment, the first lens group includes a first lens and a second lens arranged in sequence from the object side to the image side along the optical axis; a center thickness CT1 of the first lens on the optical axis, a center thickness CT2 of the second lens on the optical axis, and a sum ∑CT of the center thicknesses of the lenses included in the first lens group to the third lens group on the optical axis satisfy: 0<(CT1+CT2) / ∑CT<0.2.

[0011] In one embodiment, the first lens group includes a first lens and a second lens arranged in sequence from the object side to the image side along the optical axis; the effective focal length f1 of the first lens, the effective focal length f2 of the second lens and the effective focal length F1 of the first lens group satisfy: -2<(f1+f2) / F1<0.

[0012] In one embodiment, the third lens group includes at least a seventh lens; a curvature radius R13 of the object side surface of the seventh lens, a curvature radius R14 of the image side surface of the seventh lens, and an effective focal length F3 of the third lens group satisfy: -2<(R13+R14) / F3<2.

[0013] In one embodiment, the first lens group includes a first lens closest to the object side, and the third lens group includes a seventh lens; the effective radius DT71 of the object side surface of the seventh lens, the effective radius DT11 of the object side surface of the first lens, the effective radius DT72 of the image side surface of the seventh lens, and the effective radius DT12 of the image side surface of the first lens satisfy: 1.8 <DT71 / DT11+DT72 / DT12<2.5。

[0014] In one embodiment, the first lens group includes a second lens, and the second lens group includes a third lens; an axial distance SAG31 from the intersection of the object side surface of the third lens and the optical axis to the effective radius vertex of the object side surface of the third lens, an axial distance SAG32 from the intersection of the image side surface of the third lens and the optical axis to the effective radius vertex of the image side surface of the third lens, an axial distance SAG21 from the intersection of the object side surface of the second lens and the optical axis to the effective radius vertex of the object side surface of the second lens, and an axial distance SAG22 from the intersection of the image side surface of the second lens and the optical axis to the effective radius vertex of the image side surface of the second lens satisfy: 0.5<(SAG31+SAG32) / (SAG21+SAG22)<1.5.

[0015] In one embodiment, the second lens group includes at least a third lens, a fourth lens, and a fifth lens arranged in sequence from the object side to the image side along the optical axis, wherein the third lens is made of glass.

[0016] In one embodiment, the second lens group includes a third lens; the Abbe number V3 of the third lens and the refractive index N3 of the third lens satisfy: 45 <V3 / N3<56。

[0017] In one embodiment, the second lens group includes a third lens; the effective focal length f3 of the third lens, the center thickness CT3 of the third lens on the optical axis and the refractive index N3 of the third lens satisfy: <f3 / CT3×N3<6.5。

[0018] In one embodiment, the first lens group includes a first lens closest to the object side; a distance TTL from the object side of the first lens to the imaging plane on the optical axis satisfies: 0.2<(△T1+△T2) / TTL<0.4.

[0019] The zoom lens according to the embodiment of the present application adopts a lens architecture with three lens groups, which sequentially includes a first lens group with negative optical power, a second lens group with positive optical power, and a third lens group with negative optical power from the object side to the image side along the optical axis; there is an air gap between the lenses in each lens group; by changing the positions of the second lens group and the third lens group on the optical axis, the zoom lens can be switched between the wide-angle end state and the telephoto end state and achieve continuous multi-fold zoom; and the maximum image height of the zoom lens remains unchanged during the zoom process. With this setting of the zoom lens, the first lens group with negative optical power serves as the front fixed group, imaging the specified object plane onto the object plane of the varifocal group; the second lens group with positive optical power serves as the varifocal group that satisfies the principle of object-image exchange; the third lens group with negative optical power serves as the compensation group to compensate for the movement of the image plane, and its negative optical power is beneficial to reducing the lens size and is more suitable for mobile phone lens modules. At the same time, control the half of the diagonal length ImgH of the effective pixel area on the imaging surface of the zoom lens to satisfy 5mm < ImgH < 5.5mm, and control that when the zoom lens is in the wide-angle end state and the telephoto end state respectively, the change value △T3 of the air gap between the third lens group and the filter on the optical axis and the change value △f of the effective focal length of the zoom lens satisfy 0.5 < △T3 / △f < 1, which can ensure that the focusing stroke is within the motor stroke, improve the chip and IR ghosting at the same time, and ensure the imaging quality; at the same time, it can also satisfy the matching of the chief ray incident angle and the chip while ensuring a larger effective pixel area, preventing crosstalk or vignetting. Description of the Drawings

[0020] With reference to the accompanying drawings, through the following detailed description of non-limiting embodiments, other features, objectives, and advantages of the present application will become more apparent. In the drawings:

[0021] Figure 1 Shows a schematic structural diagram of the zoom lens according to Embodiment 1 of the present application in the telephoto end state;

[0022] Figure 2 Shows a schematic structural diagram of the zoom lens according to Embodiment 1 of the present application in the intermediate end state;

[0023] Figure 3 Shows a schematic structural diagram of the zoom lens according to Embodiment 1 of the present application in the wide-angle end state;

[0024] Figure 4 、 Figure 5 and Figure 6 Respectively show the axial chromatic aberration curve, astigmatism curve, and distortion curve of the zoom lens according to Embodiment 1 in the telephoto end state;

[0025] Figure 7 、 Figure 8 and Fig. 9The axial chromatic aberration curve, astigmatism curve and distortion curve of the zoom lens of Example 1 in the middle end state are respectively shown;

[0026] Fig.10 , Fig.11 and Fig.12 The axial chromatic aberration curve, astigmatism curve and distortion curve of the zoom lens of Example 1 at the wide-angle end state are respectively shown;

[0027] Fig.13 A schematic structural diagram of a zoom lens in a telephoto end state according to Embodiment 2 of the present application is shown;

[0028] Fig.14 A schematic structural diagram of a zoom lens in an intermediate end state according to Embodiment 2 of the present application is shown;

[0029] Fig.15 A schematic structural diagram of a zoom lens in a wide-angle end state according to Embodiment 2 of the present application is shown;

[0030] Fig.16 , Fig.17 and Fig.18 The axial chromatic aberration curve, astigmatism curve and distortion curve of the zoom lens of Example 2 at the telephoto end state are respectively shown;

[0031] Fig.19 , Fig. 20 and Fig.21 The axial chromatic aberration curve, astigmatism curve and distortion curve of the zoom lens of Example 2 in the middle end state are respectively shown;

[0032] Fig. 22 , Fig.23 and Fig.24 The axial chromatic aberration curve, astigmatism curve and distortion curve of the zoom lens of Example 2 at the wide-angle end state are respectively shown;

[0033] Fig.25 A schematic structural diagram of a zoom lens in a telephoto end state according to Embodiment 3 of the present application is shown;

[0034] Fig.26 A schematic structural diagram of a zoom lens in an intermediate end state according to Embodiment 3 of the present application is shown;

[0035] Fig. 27 A schematic structural diagram of a zoom lens in a wide-angle end state according to Embodiment 3 of the present application is shown;

[0036] Fig.28 , Fig.29 and Fig.30 The axial chromatic aberration curve, astigmatism curve and distortion curve of the zoom lens of Example 3 at the telephoto end state are respectively shown;

[0037] Fig.31 , Fig.32 and Fig.33 The axial chromatic aberration curve, the astigmatism curve and the distortion curve of the zoom lens of Example 3 in the intermediate end state are respectively shown; and

[0038] Fig.34 , Fig.35 and Fig.36 The axial chromatic aberration curve, astigmatism curve, and distortion curve of the zoom lens of Example 3 in the wide-angle end state are respectively shown. DETAILED DESCRIPTION

[0039] In order to better understand the present application, a more detailed description will be made of various aspects of the present application with reference to the accompanying drawings. It should be understood that these detailed descriptions are only descriptions of exemplary embodiments of the present application, and are not intended to limit the scope of the present application in any way. Throughout the specification, the same reference numerals refer to the same elements. The expression "and / or" includes any and all combinations of one or more of the associated listed items.

[0040] It should be noted that in this specification, the expressions of first, second, third, etc. are only used to distinguish one feature from another feature, and do not represent any limitation on the features. Therefore, without departing from the teaching of the present application, the first lens discussed below may also be referred to as the second lens or the third lens.

[0041] In the drawings, the thickness, size and shape of the lenses have been slightly exaggerated for ease of explanation. Specifically, the shapes of the spherical or aspherical surfaces shown in the drawings are shown by way of example. That is, the shapes of the spherical or aspherical surfaces are not limited to the shapes of the spherical or aspherical surfaces shown in the drawings. The drawings are only examples and are not drawn strictly to scale.

[0042] In this article, the paraxial region refers to the region near the optical axis. If the lens surface is convex and the position of the convex surface is not defined, it means that the lens surface is convex at least in the paraxial region; if the lens surface is concave and the position of the concave surface is not defined, it means that the lens surface is concave at least in the paraxial region. In this article, the surface of each lens closest to the object is called the object side surface of the lens, and the surface of each lens closest to the imaging plane is called the image side surface of the lens.

[0043] It should also be understood that the terms "comprises", "including", "having", "includes" and / or "comprising", when used in this specification, indicate the presence of the stated features, elements and / or components, but do not exclude the presence or addition of one or more other features, elements, components and / or combinations thereof. In addition, when expressions such as "at least one of..." appear after a list of listed features, they modify the entire listed features rather than modifying the individual elements in the list. In addition, when describing embodiments of the present application, "may" is used to mean "one or more embodiments of the present application". And, the term "exemplary" is intended to refer to an example or illustration.

[0044] Unless otherwise defined, all terms (including technical terms and scientific terms) used in this article have the same meaning as commonly understood by ordinary technicians in the field to which this application belongs. It should also be understood that terms (such as terms defined in commonly used dictionaries) should be interpreted as having the same meaning as their meaning in the context of the relevant technology, and will not be interpreted in an idealized or overly formal sense unless explicitly defined in this article.

[0045] It should be noted that, in the absence of conflict, the embodiments and features in the embodiments of the present application can be combined with each other. The present application will be described in detail below with reference to the accompanying drawings and in combination with the embodiments.

[0046] The features, principles and other aspects of the present application are described in detail below.

[0047] The zoom lens according to an exemplary embodiment of the present application may include three lens groups having optical power, namely, a first lens group, a second lens group, and a third lens group, which are arranged in sequence from the object side to the image side along the optical axis.

[0048] In example embodiments, the first lens group may have negative power; the second lens group may have positive power; and the third lens group may have negative power.

[0049] In exemplary embodiments, each of the lenses included in the first lens group, the second lens group, and the third lens group, respectively, may have an air space therebetween.

[0050] In an exemplary embodiment, by changing the positions of the second lens group and the third lens group on the optical axis, the zoom lens can be switched between a wide-angle end state and a telephoto end state and continuous multiple zooming can be achieved.

[0051] In an exemplary embodiment, the maximum image height of the zoom lens remains unchanged during the zooming process.

[0052] In an exemplary embodiment, the value of the maximum semi-image height of the zoom lens may be equal to half of the diagonal length of the effective pixel region on the imaging surface of the zoom lens.

[0053] In an exemplary embodiment, the zoom lens of the present application may satisfy the conditional formula 5mm < ImgH < 5.5mm, where ImgH is half of the diagonal length of the effective pixel region on the imaging surface of the zoom lens.

[0054] In an exemplary embodiment, the zoom lens further includes a filter located between the third lens group and the imaging surface of the zoom lens. The zoom lens of the present application may satisfy the conditional formula 0.5 < △T3 / △f < 1, where △T3 is the change value of the air gap on the optical axis between the third lens group and the filter when the zoom lens is in the wide-angle end state and the telephoto end state respectively; △f is the change value of the effective focal length when the zoom lens is in the wide-angle end state and the telephoto end state respectively.

[0055] The zoom lens according to the embodiment of the present application adopts a lens structure of three lens groups, which sequentially includes a first lens group with negative optical power, a second lens group with positive optical power, and a third lens group with negative optical power along the optical axis from the object side to the image side; there is an air gap between the lenses in each lens group; by changing the positions of the second lens group and the third lens group on the optical axis, the zoom lens can be switched between the wide-angle end state and the telephoto end state and achieve continuous multiple zoom; and the maximum image height of the zoom lens remains unchanged during the zoom process. Through such a setting of the zoom lens, the first lens group with negative optical power serves as the front fixed group, imaging the specified object plane to the object plane of the variable magnification group; the second lens group with positive optical power serves as the variable magnification group that satisfies the object-image exchange principle; the third lens group with negative optical power serves as the compensation group to compensate for the movement of the image plane. Its negative optical power is beneficial to reducing the lens size and is more suitable for the mobile phone lens module. At the same time, controlling half of the diagonal length ImgH of the effective pixel region on the imaging surface of the zoom lens to satisfy 5mm < ImgH < 5.5mm, and controlling the change value △T3 of the air gap on the optical axis between the third lens group and the filter when the zoom lens is in the wide-angle end state and the telephoto end state respectively and the change value △f of the effective focal length of the zoom lens to satisfy 0.5 < △T3 / △f < 1 can ensure that the focusing stroke is within the motor stroke, while improving the chip and IR ghosting and ensuring the imaging quality; at the same time, it can also satisfy the matching of the chief ray incident angle and the chip while ensuring a larger effective pixel region, preventing crosstalk or vignetting.

[0056] In an exemplary embodiment, the first lens group may include, for example, a first lens and a second lens arranged in sequence along the optical axis from the object side to the image side; the second lens group may include, for example, a third lens, a fourth lens, a fifth lens, and a sixth lens arranged in sequence along the optical axis from the object side to the image side; the third lens group may include, for example, a seventh lens.

[0057] In an exemplary embodiment, the first lens group may include, for example, a first lens and a second lens arranged in order from the object side to the image side along the optical axis; the second lens group may include, for example, a third lens, a fourth lens, and a fifth lens arranged in order from the object side to the image side along the optical axis; the third lens group may include, for example, a sixth lens and a seventh lens.

[0058] In an exemplary embodiment, the zoom lens of the present application may satisfy the conditional formula -3 < △f / ImgH < -1, where △f is the change value of the effective focal length of the zoom lens in the wide-angle end state and the telephoto end state respectively, and ImgH is half of the diagonal length of the effective pixel area on the imaging surface of the zoom lens. By controlling the ratio of the change value of the effective focal length of the zoom lens in the wide-angle end state and the telephoto end state respectively to half of the diagonal length of the effective pixel area on the imaging surface of the zoom lens within this range, the focal length of the lens can be continuously changed within the required range, and different shooting requirements can be adapted by adjusting the focal length. The change of the shooting subject is also easier to capture, so that the lens has a wider focal length selection compared with a fixed-focus lens and higher imaging quality and effect compared with digital zoom.

[0059] In an exemplary embodiment, the first lens group includes the first lens closest to the object side. The zoom lens of the present application may satisfy the conditional formula 0.5 < TTL × △tan(Semi-FOV) / EPD < 0.7, where TTL is the distance from the object side surface of the first lens to the imaging surface of the lens on the optical axis, △tan(Semi-FOV) is the change value of the tangent function of the maximum half field of view angle of the zoom lens in the wide-angle end state and the telephoto end state respectively, and EPD is the entrance pupil diameter of the zoom lens. By controlling the distance from the object side surface of the first lens to the imaging surface of the lens on the optical axis, the change value of the tangent function of the maximum half field of view angle of the zoom lens in the wide-angle end state and the telephoto end state respectively, and the entrance pupil diameter of the zoom lens to satisfy the conditional formula 0.5 < TTL × △tan(Semi-FOV) / EPD < 0.7, while ensuring that the change of the half field of view angle is within a reasonable range, it is ensured that the axial distance from the object side surface of the first lens of the optical system to the imaging surface and the entrance pupil diameter are short, ensuring the miniaturization and portability of the system. The compact structure is also conducive to resisting reliability tests such as torsion, high-altitude drop, and drum test to achieve a wider range of applications.

[0060] In an exemplary embodiment, the zoom lens of the present application further includes a filter located between the third lens group and the imaging surface, and the zoom lens of the present application can satisfy the conditional formula -0.2 < ImgH × △tan(CRA) / △T3 < 0, where ImgH is half of the diagonal length of the effective pixel region on the imaging surface of the zoom lens, △tan(CRA) is the change value of the tangent function of the maximum incident angle of the chief ray when the zoom lens is in the wide-angle end state and the telephoto end state respectively, and △T3 is the change value of the air gap between the third lens group and the filter on the optical axis when the zoom lens is in the wide-angle end state and the telephoto end state respectively. By controlling the zoom lens to satisfy the conditional formula -0.2 < ImgH × △tan(CRA) / △T3 < 0, the system stroke can be ensured to be within a reasonable range, and the remaining aberration of the front group can be effectively corrected, ensuring a better imaging picture. At the same time, the CRA angle is controlled to avoid the problem that the CRA difference in each focal segment is too large to match the chip.

[0061] In an exemplary embodiment, the zoom lens of the present application can satisfy the conditional formula 1.5% < |DISTi| < 2.5%, where DISTi is the distortion of the maximum field of view when the zoom lens is in the wide-angle end state (i.e., at the minimum focal length end). More specifically, in the exemplary embodiment, the distortion is the largest when the lens is triple zoomed. The telephoto lens has a narrow viewing range, which can better combine the person and the background, and the integrity of the photo is better; while in the zoom lens, the minimum focal length end of the zoom lens is usually used for portrait shooting, and the picture has no other impurities and is purer. To ensure this shooting effect, a smaller optical distortion is required to ensure a smaller TV distortion. By controlling the distortion of the maximum field of view when the zoom lens is at the minimum focal length end to satisfy the conditional formula 1.5% < |DISTi| < 2.5%, the picture performance can be made more pure.

[0062] In an exemplary embodiment, the zoom lens of the present application can satisfy the conditional formula -6 < (F1 + F3) / F2 < -3, where F1 is the effective focal length of the first lens group, F2 is the effective focal length of the second lens group, and F3 is the effective focal length of the third lens group. By controlling the effective focal lengths of the first lens group, the second lens group, and the third lens group to satisfy the conditional formula -6 < (F1 + F3) / F2 < -3 and reasonably distributing the ratio of the effective focal lengths of the three lens groups, on the one hand, it is beneficial to control the aperture of the entire lens and avoid too large a lens cutting edge ratio. On the other hand, the focal length values are reasonably distributed to avoid too concentrated optical power, resulting in too large optical sensitivity of a certain group, which brings great challenges to the process ability, leading to problems such as low overall yield and greatly increased manufacturing cost.

[0063] In an exemplary embodiment, the first lens group includes a first lens and a second lens arranged in sequence from the object side to the image side along the optical axis. The zoom lens of the present application can satisfy the conditional formula 0<(CT1+CT2) / ∑CT<0.2, wherein CT1 is the center thickness of the first lens on the optical axis, CT2 is the center thickness of the second lens on the optical axis, and ∑CT is the sum of the center thicknesses of the lenses in the zoom lens on the optical axis. By controlling the center thickness of the first lens on the optical axis, the center thickness of the second lens on the optical axis, and the sum of the center thicknesses of the lenses in the zoom lens on the optical axis to satisfy the conditional formula 0<(CT1+CT2) / ∑CT<0.2, problems such as actual molding and assembly caused by unreasonable thickness distribution can be avoided, such as problems such as the inability to effectively release lens stress due to excessive thickness, which seriously affects the imaging quality, and problems such as large deformation during the assembly process due to excessive thickness, lens surface variation, and a sharp decline in performance can be avoided; in addition, the field curvature of each focal length can be balanced, so that the defocus can be controlled at a better level.

[0064] In an exemplary embodiment, the first lens group includes a first lens and a second lens arranged in sequence from the object side to the image side along the optical axis. The zoom lens of the present application can satisfy the conditional formula -2<(f1+f2) / F1<0, wherein f1 is the effective focal length of the first lens, f2 is the effective focal length of the second lens, and F1 is the effective focal length of the first lens group. By controlling the effective focal length of the first lens, the effective focal length of the second lens, and the effective focal length of the first lens group to satisfy the conditional formula -2<(f1+f2) / F1<0, the sensitivity of the first lens and the second lens can be reduced to avoid too strict tolerance requirements, and the object plane imaging can be reasonably distributed to the zoom group object plane, ensuring that the combined focal length meets the zoom requirements and reducing the group stroke, thereby miniaturizing the lens to meet the requirements of the whole machine.

[0065] In an exemplary embodiment, the third lens group includes at least a seventh lens, and the zoom lens of the present application can satisfy the conditional formula -2<(R13+R14) / F3<2, wherein R13 is the radius of curvature of the object side surface of the seventh lens in the third lens group, R14 is the radius of curvature of the image side surface of the seventh lens in the third lens group, and F3 is the effective focal length of the third lens group. By controlling the radius of curvature of the object side surface of the seventh lens in the third lens group, the radius of curvature of the image side surface, and the effective focal length of the third lens group to satisfy the conditional formula -2<(R13+R14) / F3<2, the sag of the seventh lens can be controlled within a reasonable range, which can better balance the field curvature and distortion of the entire system on the one hand, and reasonably distribute the optical power of the compensation group on the other hand, and reduce the stroke of the compensation group, so as to ensure that the compensation group can meet the motor stroke requirements when switching focal lengths or AF focusing without interference.

[0066] In an exemplary embodiment, the first lens group includes a first lens closest to the object side, and the third lens group includes a seventh lens. The zoom lens of the present application can satisfy the conditional formula 1.8 < DT71 / DT11 + DT72 / DT12 < 2.5, where DT71 is the effective radius of the object side surface of the seventh lens in the third lens group, DT72 is the effective radius of the image side surface of the seventh lens in the third lens group, DT11 is the effective radius of the object side surface of the first lens in the first lens group, and DT12 is the effective radius of the image side surface of the first lens in the first lens group. By controlling the effective radius of the object side surface and the image side surface of the seventh lens and the effective radius of the object side surface and the image side surface of the first lens to satisfy the conditional formula 1.8 < DT71 / DT11 + DT72 / DT12 < 2.5, on the one hand, the vignetting value of the system can be effectively controlled, and the part of the light with poor imaging quality can be intercepted, thereby improving the resolution of the entire system; on the other hand, limited by the thickness of the mobile phone, the height of the zoom lens needs to be trimmed. The heights of the lenses of the zoom lens are basically the same, which can avoid trimming the effective diameter of too many lenses to meet the height of the lens module; at the same time, it can avoid the sharp decline of the entire optical performance caused by excessive trimming, and avoid bringing huge challenges to the processes such as processing and assembly.

[0067] In an exemplary embodiment, the first lens group includes a second lens, and the second lens group includes a third lens. The zoom lens of the present application can satisfy the conditional formula 0.5 < (SAG31 + SAG32) / (SAG21 + SAG22) < 1.5, where SAG31 is the axial distance from the intersection of the object side surface of the third lens and the optical axis to the vertex of the effective radius of the object side surface of the third lens, SAG32 is the axial distance from the intersection of the image side surface of the third lens and the optical axis to the vertex of the effective radius of the image side surface of the third lens, SAG21 is the axial distance from the intersection of the object side surface of the second lens and the optical axis to the vertex of the effective radius of the object side surface of the second lens, and SAG22 is the axial distance from the intersection of the image side surface of the second lens and the optical axis to the vertex of the effective radius of the image side surface of the second lens. By controlling the zoom lens to satisfy the conditional formula 0.5 < (SAG31 + SAG32) / (SAG21 + SAG22) < 1.5, the sagittal heights of the second lens and the third lens are reasonably controlled to avoid problems such as forming and timeliness in the actual processing process from affecting the final performance. At the same time, the position between the second lens and the third lens is the group gap position, and the lens exposure scheme is adopted. Reasonably controlling the sagittal height can avoid appearance problems such as scratches during transportation or assembly.

[0068] In an exemplary embodiment, the second lens group of the zoom lens of the present application includes at least a third lens, a fourth lens, and a fifth lens arranged in sequence from the object side to the image side along the optical axis, wherein the material of the third lens is glass. The second lens group is a variable magnification group, and reasonable focal length distribution is required to achieve the variable magnification requirement. Among them, the refractive index of the third lens has a greater influence on the temperature drift. Selecting glass material can, on the one hand, reduce chromatic aberration and the cutting ratio, and on the other hand, significantly reduce the influence of temperature drift, preventing interference phenomena from occurring during the movement between groups in special environments.

[0069] In an exemplary embodiment, the second lens group includes a third lens, and the zoom lens of the present application can satisfy the conditional formula 45 < V3 / N3 < 56, where V3 is the Abbe number of the third lens and N3 is the refractive index of the third lens. By controlling the Abbe number of the third lens and the refractive index of the third lens to satisfy the conditional formula 45 < V3 / N3 < 56, since the third lens is made of glass material, its material selection range is wider. On the premise of ensuring molding and cutting, selecting a material with a lower refractive index can provide a larger focal length, reduce the sagittal height of the remaining plastic lenses in the variable magnification group, and improve the assembly stability; selecting a higher Abbe number can better reduce the chromatic aberration of the system and ensure the color balance of the captured image.

[0070] In an exemplary embodiment, the second lens group includes a third lens, and the zoom lens of the present application can satisfy the conditional formula 3 < f3 / CT3×N3 < 6.5, where f3 is the effective focal length of the third lens, CT3 is the central thickness of the third lens on the optical axis, and N3 is the refractive index of the third lens. By controlling the effective focal length of the third lens, the central thickness of the third lens on the optical axis, and the refractive index of the third lens to satisfy the conditional formula 3 < f3 / CT3×N3 < 6.5, it is possible to meet the molding and cutting requirements on the premise of ensuring that the third lens can provide a focal length that meets the requirements; it is beneficial for the material and shape selection of the third lens to be more suitable for processing, improving the actual single-piece yield and reducing costs. In addition, it can better balance the system distortion and ensure that the captured image quality in different focal lengths does not show obvious deformation.

[0071] In an exemplary embodiment, the first lens group includes a first lens closest to the object side, and the zoom lens of the present application can satisfy the conditional formula 0.2<(△T1+△T2) / TTL<0.4, wherein △T1 is the change value of the air interval between the first lens group and the second lens group on the optical axis when the zoom lens is in the wide-angle end state and the telephoto end state respectively; △T2 is the change value of the air interval between the second lens group and the third lens group on the optical axis when the zoom lens is in the wide-angle end state and the telephoto end state respectively; TTL is the distance from the object side of the first lens to the lens imaging surface on the optical axis. By controlling the zoom lens to satisfy the conditional formula 0.2<(△T1+△T2) / TTL<0.4, on the one hand, the assembly distance requirements can be ensured to avoid interference problems caused by too small a distance between the two groups during the operation of the motor; on the other hand, it can also avoid too large a distance difference between the groups. Appropriate distance distribution is conducive to ensuring that the two motors run to the corresponding zoom distance at the same time, and realizing fast and smooth switching between different focal lengths.

[0072] In an exemplary embodiment, the zoom lens may further include at least one aperture. The aperture may be disposed at an appropriate position as required, for example, the aperture may be disposed between the object side and the first lens group. Optionally, the zoom lens may further include a filter for correcting color deviation and / or a protective glass for protecting a photosensitive element located on the imaging surface.

[0073] In an embodiment of the present application, a zoom lens may include an aspheric lens. The characteristic of an aspheric lens is that the curvature changes continuously from the center of the lens to the periphery of the lens. Unlike a spherical lens having a constant curvature from the center of the lens to the periphery of the lens, an aspheric lens has a better curvature radius characteristic, and has the advantages of improving distortion aberration and improving astigmatism aberration. After adopting an aspheric lens, the aberration occurring during imaging can be eliminated as much as possible, thereby improving the imaging quality. Optionally, the object side surface and the image side surface of each lens from the first lens to the seventh lens may both be aspheric mirror surfaces.

[0074] However, those skilled in the art should understand that, without departing from the technical solution claimed in the present application, the number of lens groups constituting the zoom lens can be changed, and the number of lenses included in each lens group can also be changed to obtain the various results and advantages described in this specification. For example, although three lens groups (including seven lenses in total) are used as an example in the embodiments, the zoom lens is not limited to including three lens groups, and the zoom lens is not limited to including seven lenses in total. If necessary, the zoom lens may also include other numbers of lens groups and other numbers of lenses.

[0075] Specific embodiments of the zoom lens applicable to the above-mentioned embodiments will be further described below with reference to the accompanying drawings.

[0076] Example 1

[0077] The following reference Figures 1 to 3 A zoom lens according to Embodiment 1 of the present application is described. Figure 1 A schematic structural diagram of a zoom lens in a telephoto end state according to Embodiment 1 of the present application is shown; Figure 2 A schematic structural diagram of a zoom lens in an intermediate end state according to Embodiment 1 of the present application is shown; Figure 3 A schematic structural diagram of a zoom lens in a wide-angle end state according to Embodiment 1 of the present application is shown.

[0078] As shown in the picture Figure 3 As shown, the zoom lens includes, in order from the object side to the image side along the optical axis: a first lens group G1, a second lens group G2, and a third lens group G3. The first lens group G1 includes a first lens E1 and a second lens E2 arranged in order from the object side to the image side along the optical axis; the second lens group G2 includes a third lens E3, a fourth lens E4, a fifth lens E5, and a sixth lens E6 arranged in order from the object side to the image side along the optical axis; and the third lens group G3 includes a seventh lens E7. In addition, the zoom lens also includes an imaging surface S17 and a filter located between the third lens group G3 and the imaging surface S17.

[0079] The first lens E1 has negative power, and its object side surface S1 is concave, and its image side surface S2 is concave. The second lens E2 has positive power, and its object side surface S3 is convex, and its image side surface S4 is concave. The third lens E3 has positive power, and its object side surface S5 is convex, and its image side surface S6 is convex. The fourth lens E4 has negative power, and its object side surface S7 is concave, and its image side surface S8 is convex. The fifth lens E5 has positive power, and its object side surface S9 is concave, and its image side surface S10 is convex. The sixth lens E6 has positive power, and its object side surface S11 is concave, and its image side surface S12 is convex. The seventh lens E7 has negative power, and its object side surface S13 is concave, and its image side surface S14 is convex. The filter, for example, has an object side surface S15 and an image side surface S16. Light from an object can pass through each surface S1 to S16 in sequence and finally be imaged on an imaging surface S17.

[0080] Table 1 shows basic parameters of the zoom lens of Example 1, wherein the units of the curvature radius and thickness / distance are both millimeters (mm).

[0081]

[0082]

[0083] Table 1

[0084] In Example 1, the object-side surface and the image-side surface of the first lens E1 to the seventh lens E7 are all aspherical surfaces, and the surface shape x of each aspherical lens can be defined by but not limited to the following aspherical surface formula:

[0085]

[0086] Wherein, x is the distance vector height from the vertex of the aspheric surface when the aspheric surface is at a height of h along the optical axis; c is the paraxial curvature of the aspheric surface, c=1 / R (i.e., the paraxial curvature c is the reciprocal of the curvature radius R in Table 1 above); k is the cone coefficient; Ai is the correction coefficient of the i-th order of the aspheric surface. The following Tables 2-1 and 2-2 give the high-order coefficients A4, A6, A8, A9, A10, A11, A12, A13, A14, A15, A16, A17, A18, A19, A20, A21, A22, A23, A24, A25, A26, A27, A28, A29, A30, A31, A32, A33, A34, A35, A36, A37, A38, A39, A40, A41, A42, A43, A44, A45, A46, A47, A48, A49, A50, A51, A52, A53, A54, A55, A56, A57, A58, A59, A60, A61, A71, A72, A73, A74, A75, A76, A77, A8, A59, A60, A80, A51, A80, A90, A10, A110, A120, A130, A140, A151, A160, A170, A180, A190, A200, A210 10 , A 12 , A 14 , A 16 , A 18 , A 20 , A 22 , A 24 , A 26 , A 28 and A 30 .

[0087] Face number A4 A6 A8 A10 A12 A14 A16 S1 -1.4121E-03 1.9916E-03 -1.0778E-03 3.6502E-04 -8.5409E-05 1.4209E-05 -1.6980E-06 S2 -3.9730E-03 4.1195E-03 -2.1080E-03 7.0402E-04 -1.6295E-04 2.6556E-05 -3.0651E-06 S3 -3.5213E-03 1.9780E-03 -7.9261E-04 2.0533E-04 -3.3292E-05 2.7886E-06 3.4410E-08 S4 -1.7442E-03 5.7021E-04 -1.5796E-04 8.7181E-06 9.8306E-06 -3.9923E-06 8.1566E-07 S5 -1.8402E-05 -3.0221E-04 2.0830E-04 -9.4482E-05 2.9043E-05 -6.2795E-06 9.7510E-07 S6 3.9785E-03 -1.1093E-03 2.0713E-04 7.8459E-06 -1.8077E-05 5.9908E-06 -1.1696E-06 S7 3.5804E-02 -1.4394E-02 5.5107E-03 -1.6565E-03 3.8106E-04 -6.6772E-05 8.8442E-06 S8 3.2717E-02 -1.2023E-02 4.2609E-03 -1.1377E-03 2.2435E-04 -3.1798E-05 2.9896E-06 S9 2.4777E-02 -2.4128E-02 1.3666E-02 -5.5249E-03 1.6788E-03 -3.8462E-04 6.5932E-05 S10 4.1657E-02 -4.0923E-02 2.5043E-02 -1.0895E-02 3.5224E-03 -8.5403E-04 1.5542E-04 S11 2.1600E-02 -2.1372E-02 1.4091E-02 -6.6441E-03 2.3105E-03 -6.0056E-04 1.1728E-04 S12 9.1717E-04 -8.4762E-04 5.2191E-04 -2.3253E-04 7.1012E-05 -1.5268E-05 2.3418E-06 S13 -1.0003E-03 3.8213E-03 -2.7825E-03 1.2274E-03 -3.6333E-04 7.5655E-05 -1.1380E-05 S14 -1.2285E-03 3.3395E-03 -2.1659E-03 8.5345E-04 -2.2614E-04 4.2233E-05 -5.7083E-06

[0088] Table 2-1

[0089]

[0090]

[0091] Table 2-2

[0092] Table 3 below shows the values ​​of some parameters of the zoom lens of Example 1 in the wide-angle end state, the middle end state and the telephoto end state, respectively, including: the effective focal length f of the zoom lens, the maximum half field of view angle Semi-FOV of the zoom lens, the chief ray incident angle CRA (Chief Ray Angle) of the zoom lens, the aperture number Fno of the zoom lens, the air gap T1 between the first lens group and the second lens group on the optical axis, the air gap T2 between the second lens group and the third lens group on the optical axis, and the air gap T3 between the third lens group and the filter on the optical axis.

[0093] Lens status / parameters f(mm) Semi-FOV(°) CRA(°) Fno T1(mm) T2(mm) T3(mm) Wide angle 16.40 18.32 24.26 2.58 5.12 9.98 1.23 Middle End 21.99 13.59 17.29 3.46 2.36 8.44 5.53 Telephoto end 26.74 11.19 15.41 4.21 0.22 8.62 7.48

[0094] Table 3

[0095] Figure 4 , Figure 7 and Fig.10The axial chromatic aberration curves of the zoom lens of Example 1 in the telephoto end state, the middle end state and the wide-angle end state are respectively shown, which indicate the deviation of the convergent focus of light of different wavelengths passing through the back of the lens. Figure 5 , Figure 8 and Fig.11 Astigmatism curves of the zoom lens of Example 1 in the telephoto end state, the intermediate end state, and the wide-angle end state are respectively shown, which represent the meridional image curvature and the sagittal image curvature. Figure 6 , Fig. 9 and Fig.12 The distortion curves of the zoom lens of Example 1 in the telephoto end state, the intermediate end state and the wide-angle end state are shown respectively, which represent the distortion magnitude values ​​corresponding to different image heights. Figures 4 to 12 It can be seen that the zoom lens provided in Example 1 can achieve good imaging quality.

[0096] Example 2

[0097] The following reference Figures 13 to 15 A zoom lens according to Embodiment 2 of the present application is described. Fig.13 A schematic structural diagram of a zoom lens in a telephoto end state according to Embodiment 2 of the present application is shown; Fig.14 A schematic structural diagram of a zoom lens in an intermediate end state according to Embodiment 2 of the present application is shown; Fig.15 A schematic structural diagram of a zoom lens in a wide-angle end state according to Embodiment 2 of the present application is shown.

[0098] like Figures 13 to 15 As shown, the zoom lens includes, in order from the object side to the image side along the optical axis: a first lens group G1, a second lens group G2, and a third lens group G3. Among them, the first lens group G1 includes a first lens E1 and a second lens E2 arranged in order from the object side to the image side along the optical axis; the second lens group G2 includes a third lens E3, a fourth lens E4, and a fifth lens E5 arranged in order from the object side to the image side along the optical axis; the third lens group G3 includes a sixth lens E6 and a seventh lens E7 arranged in order from the object side to the image side along the optical axis. In addition, the zoom lens also includes an imaging surface S17 and a filter located between the third lens group G3 and the imaging surface S17.

[0099] The first lens E1 has negative power, and its object side surface S1 is convex, and its image side surface S2 is concave. The second lens E2 has positive power, and its object side surface S3 is convex, and its image side surface S4 is concave. The third lens E3 has positive power, and its object side surface S5 is convex, and its image side surface S6 is convex. The fourth lens E4 has negative power, and its object side surface S7 is concave, and its image side surface S8 is concave. The fifth lens E5 has positive power, and its object side surface S9 is convex, and its image side surface S10 is convex. The sixth lens E6 has positive power, and its object side surface S11 is concave, and its image side surface S12 is convex. The seventh lens E7 has negative power, and its object side surface S13 is convex, and its image side surface S14 is concave. The filter, for example, has an object side surface S15 and an image side surface S16. Light from an object can pass through each surface S1 to S16 in sequence and finally be imaged on an imaging surface S17.

[0100] Table 4 shows the basic parameters of the zoom lens of Example 2, where the units of the radius of curvature and thickness / distance are both in millimeters (mm). Tables 5-1 and 5-2 show the high-order coefficients A4, A6, A8, A9, A10, A11, A12, A13, A14, A15, A16, A17, A18, A19, A20, A21, A22, A23, A24, A25, A26, A27, A28, A29, A30, A31, A32, A33, A34, A35, A36, A37, A38, A39, A40, A41, A42, A43, A44, A45, A46, A47, A48, A49, A50, A51, A52, A53, A54, A55, A5 10 , A 12 , A 14 , A 16 , A 18 , A 20 , A 22 , A 24 , A 26 , A 28 and A 30 , wherein each aspheric surface shape can be defined by the formula (1) given in the above embodiment 1.

[0101]

[0102] Table 4

[0103] Face number A4 A6 A8 A10 A12 A14 A16 S1 -1.5022E-03 4.6277E-04 -1.8388E-04 -5.4723E-07 2.2692E-05 -8.7419E-06 1.8019E-06 S2 -1.1127E-03 4.0344E-04 7.3629E-04 -8.8135E-04 4.3303E-04 -1.2544E-04 2.3936E-05 S3 -1.3670E-03 -5.7977E-04 1.4903E-03 -1.1923E-03 5.1446E-04 -1.3981E-04 2.5713E-05 S4 -1.4736E-03 -7.2353E-04 1.1330E-03 -8.4144E-04 3.7078E-04 -1.0689E-04 2.1259E-05 S5 1.4642E-04 6.0339E-05 -1.4798E-04 1.3637E-04 -7.1356E-05 2.4063E-05 -5.5445E-06 S6 -1.0073E-03 4.5664E-04 -3.1509E-04 1.8440E-04 -7.5822E-05 2.2018E-05 -4.6140E-06 S7 -2.3928E-03 5.3888E-04 4.2622E-04 -3.6878E-04 1.5667E-04 -4.0575E-05 6.0461E-06 S8 -1.2668E-03 1.1757E-03 -5.0940E-04 5.6126E-04 -4.7385E-04 2.6268E-04 -9.8936E-05 S9 -1.8207E-03 -2.8936E-04 4.3087E-04 -3.8559E-04 2.2699E-04 -9.2789E-05 2.7075E-05 S10 -1.0317E-03 8.3036E-05 -2.3201E-05 -3.8485E-05 4.2972E-05 -2.2282E-05 7.1956E-06 S11 1.3982E-03 2.9331E-04 -2.5818E-04 1.3225E-04 -4.5910E-05 1.1473E-05 -2.1221E-06 S12 -2.0322E-03 8.6784E-04 -3.9030E-04 1.8106E-04 -6.5229E-05 1.7233E-05 -3.3090E-06 S13 -1.2951E-02 1.6396E-03 -2.5872E-04 3.3695E-05 3.5778E-06 -3.9779E-06 1.2565E-06 S14 -5.8409E-03 7.3525E-04 -1.1564E-04 2.8390E-05 -7.2402E-06 1.4167E-06 -1.9907E-07

[0104] Table 5-1

[0105]

[0106]

[0107] Table 5-2

[0108] Table 6 below shows the values ​​of some parameters of the zoom lens of Example 2 in the wide-angle end state, the middle end state and the telephoto end state, respectively, including: the effective focal length f of the zoom lens, the maximum half field of view angle Semi-FOV of the zoom lens, the chief ray incident angle CRA (Chief Ray Angle) of the zoom lens, the aperture number Fno of the zoom lens, the air gap T1 between the first lens group and the second lens group on the optical axis, the air gap T2 between the second lens group and the third lens group on the optical axis, and the air gap T3 between the third lens group and the filter on the optical axis.

[0109] Lens status / parameters f(mm) Semi-FOV(°) CRA(°) Fno T1(mm) T2(mm) T3(mm) Wide angle 16.27 18.51 25.10 2.37 4.94 4.36 0.95 Middle End 21.72 13.68 20.91 3.17 2.74 1.69 5.80 Telephoto end 27.13 11.00 16.96 3.95 0.13 0.38 9.73

[0110] Table 6

[0111] Fig.16 , Fig.19 and Fig. 22 The axial chromatic aberration curves of the zoom lens of Example 2 in the telephoto end state, the middle end state and the wide-angle end state are respectively shown, which indicate the deviation of the convergent focus of light of different wavelengths passing through the back of the lens. Fig.17 , Fig. 20 and Fig.23 Astigmatism curves of the zoom lens of Example 2 in the telephoto end state, the intermediate end state, and the wide-angle end state are respectively shown, which represent the meridional image curvature and the sagittal image curvature. Fig.18 , Fig.21 and Fig.24 The distortion curves of the zoom lens of Example 2 in the telephoto end state, the middle end state and the wide-angle end state are shown respectively, which represent the distortion magnitude values ​​corresponding to different image heights. Figures 16 to 24 It can be seen that the zoom lens provided in Example 2 can achieve good imaging quality.

[0112] Example 3

[0113] The following reference Figure 25 to Figure 27 A zoom lens according to Embodiment 3 of the present application is described. Fig.25 A schematic structural diagram of a zoom lens in a telephoto end state according to Embodiment 3 of the present application is shown; Fig.26 A schematic structural diagram of a zoom lens in an intermediate end state according to Embodiment 3 of the present application is shown; Fig. 27 A schematic structural diagram of a zoom lens in a wide-angle end state according to Embodiment 3 of the present application is shown.

[0114] like Figure 25 to Figure 27As shown, the zoom lens includes, in order from the object side to the image side along the optical axis: a first lens group G1, a second lens group G2, and a third lens group G3. Among them, the first lens group G1 includes a first lens E1 and a second lens E2 arranged in order from the object side to the image side along the optical axis; the second lens group G2 includes a third lens E3, a fourth lens E4, and a fifth lens E5 arranged in order from the object side to the image side along the optical axis; the third lens group G3 includes a sixth lens E6 and a seventh lens E7 arranged in order from the object side to the image side along the optical axis. In addition, the zoom lens also includes an imaging surface S17 and a filter located between the third lens group G3 and the imaging surface S17.

[0115] The first lens E1 has negative power, and its object side surface S1 is concave, and its image side surface S2 is concave. The second lens E2 has positive power, and its object side surface S3 is convex, and its image side surface S4 is concave. The third lens E3 has positive power, and its object side surface S5 is convex, and its image side surface S6 is convex. The fourth lens E4 has positive power, and its object side surface S7 is convex, and its image side surface S8 is convex. The fifth lens E5 has positive power, and its object side surface S9 is convex, and its image side surface S10 is concave. The sixth lens E6 has negative power, and its object side surface S11 is concave, and its image side surface S12 is concave. The seventh lens E7 has negative power, and its object side surface S13 is convex, and its image side surface S14 is concave. The filter, for example, has an object side surface S15 and an image side surface S16. Light from an object can pass through each surface S1 to S16 in sequence and finally be imaged on an imaging surface S17.

[0116] Table 7 shows the basic parameters of the zoom lens of Example 3, where the units of the radius of curvature and thickness / distance are all in millimeters (mm). Tables 8-1 and 8-2 show the high-order coefficients A4, A6, A8, A9, A10, A11, A12, A13, A14, A15, A16, A17, A18, A19, A20, A21, A22, A23, A24, A25, A26, A27, A28, A29, A30, A31, A32, A33, A34, A35, A36, A37, A38, A39, A40, A41, A42, A43, A44, A45, A46, A47, A48, A49, A50, A51, A52, A53, A54, A55, A5 10 , A 12 , A 14 , A 16 , A 18 , A 20 , A 22 , A 24 , A 26 , A 28 and A 30 , wherein each aspheric surface shape can be defined by the formula (1) given in the above embodiment 1.

[0117]

[0118] Table 7

[0119] Face number A4 A6 A8 A10 A12 A14 A16 S1 6.3413E-03 -1.9472E-04 -8.1265E-04 4.6728E-04 -1.5123E-04 3.2826E-05 -5.0341E-06 S2 2.2641E-03 6.4825E-03 -6.1977E-03 3.1443E-03 -1.0418E-03 2.3965E-04 -3.9357E-05 S3 -5.9064E-03 5.2633E-03 -4.1144E-03 2.0522E-03 -6.8901E-04 1.6159E-04 -2.7050E-05 S4 -2.8311E-03 4.3380E-05 1.1755E-04 -4.3444E-05 3.1698E-06 2.2923E-06 -8.8033E-07 S5 -1.9031E-04 1.4157E-05 1.4451E-05 -1.5985E-05 7.0460E-06 -1.8621E-06 3.2598E-07 S6 -1.1218E-04 -2.3500E-04 2.9612E-04 -1.5935E-04 5.3321E-05 -1.2541E-05 2.1506E-06 S7 -1.0014E-04 -2.5892E-04 3.6920E-04 -2.1860E-04 8.5320E-05 -2.3809E-05 4.7819E-06 S8 9.8165E-03 -1.0757E-02 6.3924E-03 -2.0965E-03 3.4532E-04 5.4047E-07 -1.3654E-05 S9 8.1361E-03 -9.4196E-03 4.9683E-03 -1.1326E-03 -1.0698E-04 1.4983E-04 -4.8544E-05 S10 6.8866E-04 -2.3184E-04 -7.1193E-04 1.0355E-03 -6.9592E-04 2.8866E-04 -8.0779E-05 S11 5.3937E-04 6.0609E-05 -3.6533E-05 2.9487E-05 -1.5402E-05 5.2337E-06 -1.2146E-06 S12 -3.1016E-04 9.7939E-05 2.8828E-05 -2.5183E-05 1.1692E-05 -3.7169E-06 8.3407E-07 S13 -1.6548E-03 7.4200E-05 -1.1471E-05 5.1187E-06 -1.5979E-06 3.2970E-07 -4.6616E-08 S14 -1.2953E-03 4.8461E-05 -1.4151E-05 7.1242E-06 -2.1851E-06 4.3909E-07 -6.0420E-08

[0120] Table 8-1

[0121]

[0122]

[0123] Table 8-2

[0124] Table 9 below shows the values ​​of some parameters of the zoom lens of Example 3 in the wide-angle end state, the middle end state and the telephoto end state, respectively, including: the effective focal length f of the zoom lens, the maximum half field of view angle Semi-FOV of the zoom lens, the chief ray incident angle CRA (Chief Ray Angle) of the zoom lens, the aperture number Fno of the zoom lens, the air gap T1 between the first lens group and the second lens group on the optical axis, the air gap T2 between the second lens group and the third lens group on the optical axis, and the air gap T3 between the third lens group and the filter on the optical axis.

[0125] Lens status / parameters f(mm) Semi-FOV(°) CRA(°) Fno T1(mm) T2(mm) T3(mm) Wide angle 16.58 18.21 16.99 2.73 7.54 6.14 1.71 Middle End 22.03 13.89 15.26 3.63 4.36 3.75 7.28 Telephoto end 27.05 11.29 13.77 4.45 1.89 3.58 9.91

[0126] Table 9

[0127] Fig.28 , Fig.31 and Fig.34 The axial chromatic aberration curves of the zoom lens of Example 3 in the telephoto end state, the middle end state and the wide-angle end state are respectively shown, which indicate the deviation of the convergent focus of light of different wavelengths passing through the back of the lens. Fig.29 , Fig.32 and Fig.35 Astigmatism curves of the zoom lens of Example 3 in the telephoto end state, the intermediate end state, and the wide-angle end state are respectively shown, which represent the meridional image surface curvature and the sagittal image surface curvature. Fig.30 , Fig.33 and Fig.36 The distortion curves of the zoom lens of Example 3 in the telephoto end state, the middle end state and the wide-angle end state are shown respectively, which represent the distortion magnitude values ​​corresponding to different field angles. Figures 28 to 36 It can be seen that the zoom lens provided in Example 3 can achieve good imaging quality.

[0128] In addition, in Examples 1 to 3, half the diagonal length ImgH of the effective pixel area on the imaging plane of the zoom lens, the entrance pupil diameter EPD of the zoom lens, the effective focal length F1 of the first lens group, the effective focal length F2 of the second lens group, the effective focal length F3 of the third lens group, and the effective focal length values ​​f1 to f7 of the first lens to the seventh lens are respectively as shown in Table 10 below.

[0129]

[0130]

[0131] Table 10

[0132] The zoom lenses in Examples 1 to 3 respectively satisfy the conditions shown in Table 11.

[0133] Conditional / Example Example 1 Example 2 Example 3 △T3 / △f 0.60 0.81 0.78 △f / ImgH -1.94 -2.04 -1.95 TTL×△tan(Semi-FOV) / EPD 0.64 0.53 0.67 ImgH×△tan(CRA) / △T3 -0.15 -0.10 -0.04 |DISTi| 1.98 2.06 1.64 (F1+F3) / F2 -3.91 -5.54 -5.67 (CT1+CT2) / ∑CT 0.16 0.16 0.09 (f1+f2) / F1 -0.97 -0.76 -1.63 (R13+R14) / F3 1.56 -1.92 -0.44 DT71 / DT11+DT72 / DT12 1.94 2.26 2.32 (SAG31+SAG32) / (SAG21+SAG22) 1.41 0.72 1.03 V3 / N3 54.40 54.40 47.25 f3 / CT3×N3 3.12 5.09 6.07 (△T1+△T2) / TTL 0.21 0.34 0.26

[0134] Table 11

[0135] The present application also provides an imaging device, which is provided with an electronic photosensitive element for imaging, and the electronic photosensitive element can be a charge coupled device (CCD) or a complementary metal oxide semiconductor (CMOS). The imaging device can be an independent imaging device such as a digital camera, or an imaging module integrated in a mobile electronic device such as a mobile phone. The imaging device is equipped with the zoom lens described above.

[0136] The above description is only a preferred embodiment of the present application and an explanation of the technical principles used. Those skilled in the art should understand that the scope of protection involved in the present application is not limited to the technical solution formed by a specific combination of the above technical features, but should also cover other technical solutions formed by any combination of the above technical features or their equivalent features without departing from the concept of the present application. For example, the above features are replaced with the technical features with similar functions disclosed in the present application (but not limited to) to form a technical solution.

Claims

1. A zoom lens, characterized in that: It sequentially includes from the object side to the image side along the optical axis: A first lens group with negative optical power; A second lens group with positive optical power; and A third lens group with negative optical power; There is an air gap between each lens in the first lens group to the third lens group; By changing the positions of the second lens group and the third lens group on the optical axis, the zoom lens is switched between the wide-angle end state and the telephoto end state and continuous zooming is achieved; and the maximum image height of the zoom lens remains unchanged during the zooming process; The zoom lens further includes a filter located between the third lens group and the imaging surface of the zoom lens; and The zoom lens satisfies: 5mm < ImgH < 5.5mm, and 0.5 < △T3 / △f < 1, where ImgH is half of the diagonal length of the effective pixel area on the imaging surface; △T3 is the change value of the air gap on the optical axis between the third lens group and the filter when the zoom lens is in the wide-angle end state and the telephoto end state respectively; △f is the change value of the effective focal length when the zoom lens is in the wide-angle end state and the telephoto end state respectively.

2. The zoom lens according to claim 1, wherein: Satisfies: -3 < △f / ImgH < -1.

3. The zoom lens according to claim 1, wherein: The first lens group includes a first lens closest to the object side; The distance TTL from the object side surface of the first lens to the imaging surface on the optical axis, the change value △tan(Semi-FOV) of the tangent function of the maximum half field of view angle of the zoom lens when the zoom lens is in the wide-angle end state and the telephoto end state respectively, and the entrance pupil diameter EPD of the zoom lens satisfy: 0.5 < TTL×△tan(Semi-FOV) / EPD < 0.

7.

4. The zoom lens according to claim 1, wherein: The zoom lens further includes a filter located between the third lens group and the imaging surface; When the zoom lens is in the wide-angle end state and the telephoto end state respectively, the change value △tan(CRA) of the tangent function of the maximum incident angle of the chief ray of the zoom lens, and the change value △T3 of the air gap on the optical axis between the third lens group and the filter satisfy: -0.2 < ImgH×△tan(CRA) / △T3 < 0.

5. The zoom lens according to claim 1, wherein: The distortion DISTi of the maximum field of view when the zoom lens is in the wide-angle end state satisfies: 1.5% < |DISTi| < 2.5%.

6. The zoom lens according to claim 1, wherein: The effective focal length F1 of the first lens group, the effective focal length F2 of the second lens group, and the effective focal length F3 of the third lens group satisfy: -6 < (F1 + F3) / F2 < -3.

7. The zoom lens according to claim 1, wherein: The first lens group includes a first lens and a second lens arranged sequentially from the object side to the image side along the optical axis; The central thickness CT1 of the first lens on the optical axis, the central thickness CT2 of the second lens on the optical axis, and the sum ∑CT of the central thicknesses of each lens included in the first lens group to the third lens group on the optical axis satisfy: 0 < (CT1 + CT2) / ∑CT < 0.

2.

8. The zoom lens according to claim 1, wherein: The first lens group includes a first lens and a second lens arranged sequentially from the object side to the image side along the optical axis; The effective focal length f1 of the first lens, the effective focal length f2 of the second lens and the effective focal length F1 of the first lens group satisfy: -2<(f1+f2) / F1<0.

9. The zoom lens according to claim 1, wherein: The third lens group includes at least a seventh lens; The curvature radius R13 of the object side surface of the seventh lens, the curvature radius R14 of the image side surface of the seventh lens and the effective focal length F3 of the third lens group satisfy: -2<(R13+R14) / F3<2.

10. The zoom lens according to claim 1, wherein: The first lens group includes a first lens closest to the object side, and the third lens group includes a seventh lens; The effective radius DT71 of the object side surface of the seventh lens, the effective radius DT11 of the object side surface of the first lens, the effective radius DT72 of the image side surface of the seventh lens and the effective radius DT12 of the image side surface of the first lens satisfy: 1.8 <DT71 / DT11+DT72 / DT12<2.5。 11. The zoom lens according to claim 1, wherein: The first lens group includes a second lens, and the second lens group includes a third lens; An axial distance SAG31 from the intersection of the object side surface of the third lens and the optical axis to the effective radius vertex of the object side surface of the third lens, an axial distance SAG32 from the intersection of the image side surface of the third lens and the optical axis to the effective radius vertex of the image side surface of the third lens, an axial distance SAG21 from the intersection of the object side surface of the second lens and the optical axis to the effective radius vertex of the object side surface of the second lens, and an axial distance SAG22 from the intersection of the image side surface of the second lens and the optical axis to the effective radius vertex of the image side surface of the second lens satisfy: 0.5<(SAG31+SAG32) / (SAG21+SAG22)<1.

5.

12. The zoom lens according to claim 1, wherein: The second lens group at least includes a third lens, a fourth lens and a fifth lens arranged in sequence from the object side to the image side along the optical axis, wherein the third lens is made of glass.

13. The zoom lens according to claim 1, wherein: The second lens group includes a third lens; The Abbe number V3 of the third lens and the refractive index N3 of the third lens satisfy: 45 <V3 / N3<56。 14. The zoom lens according to claim 1, wherein: The second lens group includes a third lens; The effective focal length f3 of the third lens, the center thickness CT3 of the third lens on the optical axis and the refractive index N3 of the third lens satisfy: 3 <f3 / CT3×N3<6.5。 15. The zoom lens according to claim 1, wherein: The first lens group includes a first lens closest to the object side; The distance TTL from the object side of the first lens to the imaging surface on the optical axis satisfies: 0.2<(△T1+△T2) / TTL<0.4.

Images