Zoom lens

Abstract

The invention provides a zoom lens, which comprises six lenses which sequentially comprise a first group with positive focal power and a second group with negative focal power from an object side to an imaging surface along an optical axis, the first group includes, in order from an object side to an imaging plane; a first lens, a second lens, a third lens, and a fourth lens; the first lens has negative focal power; the second lens has negative focal power; the third lens has focal power; the fourth lens has positive focal power; the second group sequentially comprises a fifth lens and a sixth lens from the object side to the imaging surface; the fifth lens has negative focal power; the sixth lens has negative focal power; according to the zoom lens provided by the invention, through dynamic movement of the first group and the second group on the optical axis, optical lossless zooming of the lens between a wide-angle state and a long-focus state can be realized, and an excellent effect of compatibility of wide-angle shooting and long-focus shooting can be realized.

Description

Technical Field

[0001] The present invention relates to the technical field of imaging lenses, and particularly to a zoom lens. Background Art

[0002] With the rapid development of technologies for portable electronic devices such as smart phones, consumers' demands for photographing devices are continuously increasing. Limited by the requirement of thinning of electronic devices, a pseudo-zoom function is basically achieved by using multiple fixed-focus lenses and digital cropping. This method has great losses in imaging effects and performance, and cannot be compared with the shooting effects obtained by true optical zoom of traditional cameras, greatly reducing the zoom effect experience of portable electronic devices such as mobile phones. Therefore, it is necessary to develop an optical lossless zoom lens with a small volume and excellent zoom performance. Summary of the Invention

[0003] In view of the above problems, the object of the present invention is to provide a zoom lens, which can achieve optical lossless zoom of the lens between a wide-angle state and a telephoto state by changing the air interval distance between different groups.

[0004] The technical solution adopted by the present invention is as follows: A zoom lens, comprising a total of six lenses, which sequentially include, along the optical axis from the object side to the imaging surface: a first group with a positive optical power and a second group with a negative optical power; The first group sequentially includes, from the object side to the imaging surface: a first lens, a second lens, a third lens, and a fourth lens; The first lens has a negative optical power, its object side surface is concave near the optical axis, and its image side surface is convex near the optical axis; The second lens has a negative optical power, its object side surface is convex, and its image side surface is concave; The third lens has an optical power, its object side surface is convex, and its image side surface is concave near the optical axis; The fourth lens has a positive optical power, its object side surface is convex near the optical axis, and its image side surface is convex; The second group sequentially includes a fifth lens and a sixth lens from the object side to the imaging surface; The fifth lens has a negative optical power, its object side surface is concave, and its image side surface is convex near the optical axis; The sixth lens has a negative optical power, and its image side surface is concave near the optical axis; The first group and the second group can be dynamically moved on the optical axis to achieve zoom switching of the zoom lens between a wide-angle state and a telephoto state; Wherein, the effective focal length fT of the zoom lens in the telephoto state and the effective focal length fW of the zoom lens in the wide-angle state satisfy: 1.25 < fT / fW < 1.5.

[0005] Compared with the prior art, the zoom lens provided by the present invention can achieve optical lossless zoom well. By changing the air interval distance between different groups, the zoom lens can achieve zoom switching between the wide-angle state and the telephoto state, realizing a large zoom ratio, achieving the excellent effect of compatibility between wide-angle shooting and telephoto shooting, and having one or more advantages such as miniaturization, large field of view angle, and high-quality imaging, greatly improving the user experience effect. BRIEF DESCRIPTION OF THE DRAWINGS

[0006] The above and / or additional aspects and advantages of the present invention will become obvious and easy to understand from the description of the embodiments in conjunction with the following drawings, where: Figure 1 FIG. 9 is a schematic structural diagram of the zoom lens in the wide-angle state in Embodiment 1 of the present invention.

[0007] Figure 2 FIG. 13 is a schematic structural diagram of the zoom lens in the telephoto state in Embodiment 1 of the present invention.

[0008] Figure 3 FIG. 17 is an F-Tan(Theta) distortion curve graph of the zoom lens in the wide-angle state in Embodiment 1 of the present invention.

[0009] Figure 4 FIG. 21 is an axial aberration curve graph of the zoom lens in the wide-angle state in Embodiment 1 of the present invention.

[0010] Figure 5 FIG. 25 is a lateral chromatic aberration curve graph of the zoom lens in the wide-angle state in Embodiment 1 of the present invention.

[0011] Figure 6 FIG. 29 is an F-Tan(Theta) distortion curve graph of the zoom lens in the telephoto state in Embodiment 1 of the present invention.

[0012] Figure 7 FIG. 33 is an axial aberration curve graph of the zoom lens in the telephoto state in Embodiment 1 of the present invention.

[0013] Figure 8 FIG. 37 is a lateral chromatic aberration curve graph of the zoom lens in the telephoto state in Embodiment 1 of the present invention.

[0014] Figure 9 FIG. 41 is a schematic structural diagram of the zoom lens in the wide-angle state in Embodiment 2 of the present invention.

[0015] Figure 10 FIG. 45 is a schematic structural diagram of the zoom lens in the telephoto state in Embodiment 2 of the present invention.

[0016] Figure 11 FIG. 49 is an F-Tan(Theta) distortion curve graph of the zoom lens in the wide-angle state in Embodiment 2 of the present invention.

[0017] Figure 12 This is the axial aberration curve graph of the zoom lens in the wide-angle state in Embodiment 2 of the present invention.

[0018] Figure 13 This is the lateral chromatic aberration curve graph of the zoom lens in the wide-angle state in Embodiment 2 of the present invention.

[0019] Figure 14 This is the F-Tan(Theta) distortion curve graph of the zoom lens in the telephoto state in Embodiment 2 of the present invention.

[0020] Figure 15 This is the axial aberration curve graph of the zoom lens in the telephoto state in Embodiment 2 of the present invention.

[0021] Figure 16 This is the lateral chromatic aberration curve graph of the zoom lens in the telephoto state in Embodiment 2 of the present invention.

[0022] Figure 17 This is the structural schematic diagram of the zoom lens in the wide-angle state in Embodiment 3 of the present invention.

[0023] Figure 18 This is the structural schematic diagram of the zoom lens in the telephoto state in Embodiment 3 of the present invention.

[0024] Figure 19 This is the F-Tan(Theta) distortion curve graph of the zoom lens in the wide-angle state in Embodiment 3 of the present invention.

[0025] Figure 20 This is the axial aberration curve graph of the zoom lens in the wide-angle state in Embodiment 3 of the present invention.

[0026] Figure 21 This is the lateral chromatic aberration curve graph of the zoom lens in the wide-angle state in Embodiment 3 of the present invention.

[0027] Figure 22 This is the F-Tan(Theta) distortion curve graph of the zoom lens in the telephoto state in Embodiment 3 of the present invention.

[0028] Figure 23 This is the axial aberration curve graph of the zoom lens in the telephoto state in Embodiment 3 of the present invention.

[0029] Figure 24 This is the lateral chromatic aberration curve graph of the zoom lens in the telephoto state in Embodiment 3 of the present invention.

[0030] Figure 25 This is the structural schematic diagram of the zoom lens in the wide-angle state in Embodiment 4 of the present invention.

[0031] Figure 26Schematic diagram of the zoom lens in the telephoto state in Embodiment 4 of the present invention.

[0032] Figure 27 F-Tan(Theta) distortion curve of the zoom lens in the wide-angle state in Embodiment 4 of the present invention.

[0033] Figure 28 Axial aberration curve of the zoom lens in the wide-angle state in Embodiment 4 of the present invention.

[0034] Figure 29 Lateral chromatic aberration curve of the zoom lens in the wide-angle state in Embodiment 4 of the present invention.

[0035] Figure 30 F-Tan(Theta) distortion curve of the zoom lens in the telephoto state in Embodiment 4 of the present invention.

[0036] Figure 31 Axial aberration curve of the zoom lens in the telephoto state in Embodiment 4 of the present invention.

[0037] Figure 32 Lateral chromatic aberration curve of the zoom lens in the telephoto state in Embodiment 4 of the present invention.

[0038] The following specific embodiments will further illustrate the present invention in conjunction with the above-mentioned drawings. Specific Embodiments

[0039] To better understand the present application, various aspects of the present application will be described in more detail with reference to the accompanying drawings. It should be understood that these detailed descriptions are only descriptions of the embodiments of the present application and do not 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 such as 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 teachings of the present invention, the first lens discussed below may also be referred to as the second lens or the third lens.

[0041] In the drawings, for the sake of clarity, the thickness, dimensions, and shape of the lenses have been slightly exaggerated. Specifically, the spherical or aspherical shapes shown in the drawings are shown by way of example. That is, the spherical or aspherical shapes are not limited to the spherical or aspherical shapes shown in the drawings. The drawings are for illustrative purposes only and are not drawn to an exact scale.

[0042] In this text, 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. The surface of each lens closest to the object being photographed is called the object side surface of the lens, and the surface of each lens closest to the imaging surface is called the image side surface of the lens.

[0043] It should also be understood that the terms "comprising", "comprising of", "having", "containing" and / or "containing of", when used in this specification, denote the presence of the stated features, elements and / or components, but do not preclude the presence or addition of one or more other features, elements, components and / or combinations thereof. In addition, when an expression such as "at least one of..." appears after a list of listed features, it modifies the entire list of listed features, rather than an individual element in the list. In addition, when describing embodiments of the present application, the use of "may" means "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 used herein (including technical and scientific terms) have the same meaning as commonly understood by one of ordinary skill in the art to which this application belongs. It should also be understood that terms (such as those defined in a common dictionary) should be interpreted as having a meaning consistent with their meaning in the context of the relevant art, and will not be interpreted in an idealized or overly formal sense unless expressly so defined herein.

[0045] It should be noted that, without conflict, the embodiments in the present application and the features in the embodiments may be combined with each other. The present application will be described in detail below with reference to the drawings and in conjunction with the embodiments.

[0046] The zoom lens provided by the embodiment of the present invention has a total of six lenses, which sequentially include, along the optical axis from the object side to the imaging surface: a first group with positive optical power and a second group with negative optical power. The first group and the second group move dynamically on the optical axis to achieve the zoom switching of the zoom lens between the wide-angle state and the telephoto state. The first group sequentially includes from the object side to the imaging surface: a first lens, a second lens, a third lens, and a fourth lens; the first lens has negative optical power, its object side surface is concave near the optical axis, and its image side surface is convex near the optical axis; the second lens has negative optical power, its object side surface is convex, and its image side surface is concave; the third lens may have positive or negative optical power, its object side surface is convex, and its image side surface is concave near the optical axis; the fourth lens has positive optical power, its object side surface is convex near the optical axis, and its image side surface is convex. The second group sequentially includes a fifth lens and a sixth lens from the object side to the imaging surface; the fifth lens has negative optical power, its object side surface is concave, and its image side surface is convex near the optical axis; the sixth lens has negative optical power, its object side surface may be concave or convex, and its image side surface is concave near the optical axis. The air gap between the first group and the second group and between the second group and the imaging surface on the optical axis is variable. By changing the air gap distance between different groups, optical lossless zoom of the lens between the wide-angle state and the telephoto state can be achieved.

[0047] In some embodiments, the zoom lens may further include a diaphragm, and the diaphragm may be located between the second lens and the third lens. It can be understood that the diaphragm is used to limit the amount of incident light to change the brightness of the image. When the diaphragm is located between the second lens and the third lens, it is convenient for correcting the diaphragm aberration. It can be understood that when the first group moves dynamically on the optical axis, the diaphragm moves synchronously.

[0048] In some embodiments, the zoom lens may further include a filter, and the filter is disposed between the sixth lens and the imaging surface. The filter is used to filter out interfering light to prevent the interfering light from reaching the imaging surface of the zoom lens and affecting normal imaging.

[0049] In some embodiments, the effective focal length fT of the zoom lens in the telephoto state and the effective focal length fW of the zoom lens in the wide-angle state satisfy: 1.25 < fT / fW < 1.5. By satisfying the above range, a larger magnification ratio can be obtained, and excellent zoom performance can be achieved. More specifically, 1.27 < fT / fW < 1.48.

[0050] In some embodiments, the total optical length TTL of the zoom lens and the effective focal length f of the zoom lens satisfy: 1.7 < TTL / f < 2.7. Satisfying the above range can effectively limit the length of the lens and is conducive to the miniaturization of the zoom lens. It can be understood that the effective focal length of the zoom lens includes the effective focal length of the zoom lens in the telephoto state and the effective focal length of the zoom lens in the wide-angle state. More specifically, 1.81 < TTL / f < 2.6.

[0051] In some embodiments, the total optical length TTL of the zoom lens and the image height IH corresponding to the maximum field of view angle of the zoom lens satisfy: 1 < TTL / IH < 1.4. Satisfying the above range can better achieve the miniaturization of the lens. At the same time, when ensuring the same total length of the lens, it has a larger image plane and can better achieve high-definition imaging of the lens. More specifically, 1.08 < TTL / IH < 1.38.

[0052] In some embodiments, the image height IH corresponding to the maximum field of view angle of the zoom lens, the effective focal length f of the zoom lens, and the maximum field of view angle FOV of the zoom lens satisfy: 0.96 < (IH / 2) / (f × Tan(FOV / 2)) < 1.04. Satisfying the above range makes the distortion within a reasonable range.

[0053] In some embodiments, the maximum field of view angle FOV of the zoom lens and the f-number FNO of the zoom lens satisfy: 30° < FOV / FNO < 46°. Satisfying the above range defines that the zoom lens has a suitable field of view angle and f-number, can collect light at a large angle, and obtain good imaging quality. More specifically, 30.46° < FOV / FNO < 45.63°.

[0054] In some embodiments, the image height IH corresponding to the maximum field of view angle of the zoom lens and the entrance pupil diameter EPD of the zoom lens satisfy: 3.3 < IH / EPD < 4.5. Satisfying the above range can increase the width of the light beam incident on the zoom lens, improve the brightness of the zoom lens at the image plane, and avoid vignetting. More specifically, 3.45 < IH / EPD < 4.31.

[0055] In some embodiments, the image height IH corresponding to the maximum field of view angle of the zoom lens and the effective focal length f of the zoom lens satisfy: 1.4 < IH / f < 2.2. Satisfying the above range controls the image height and focal length of the zoom lens within a reasonable range, helps to control the zoom ratio within a reasonable range, and thus improves the imaging quality of the zoom lens. More specifically, 1.43 < IH / f < 2.13.

[0056] In some embodiments, the total optical length TTLT of the zoom lens in the telephoto state and the zoom ratio τ of the zoom lens satisfy: 4 mm < TTLT / τ < 5 mm. Wherein, the zoom ratio τ is fT / fW, that is, the ratio of the effective focal length fT of the zoom lens in the telephoto state to the effective focal length fW of the zoom lens in the wide-angle state. Satisfying the above range is beneficial to ensuring the miniaturization of the zoom system while expanding the zoom range. More specifically, 4.2 mm < TTLT / τ < 4.89 mm.

[0057] In some embodiments, the effective focal length f of the zoom lens and the focal length f1 of the first lens satisfy: -11 < f1 / f < -4.5; the curvature radius R1 of the object side surface of the first lens and the effective focal length f of the zoom lens satisfy: -1.5 < R1 / f < -0.6; the curvature radius R2 of the image side surface of the first lens and the effective focal length f of the zoom lens satisfy: -2.9 < R2 / f < -0.8. Satisfying the above range, by setting the first lens to have a negative refractive power and a suitable surface shape, it is beneficial for the first lens to receive a larger angle of light and collect as much light as possible into the rear optical system, increasing the light flux while achieving a large field of view. More specifically, -10.04 < f1 / f < -4.66; -1.47 < R1 / f < -0.63; -2.84 < R2 / f < -0.83.

[0058] In some embodiments, the focal length f4 of the fourth lens and the effective focal length f of the zoom lens satisfy: 0.4 < f4 / f < 0.62. Satisfying the above conditions, by setting the fourth lens to have a positive optical power, it is beneficial for light to converge, enabling the light trend to smoothly transition to the rear, reducing the height of the light incident on the rear, slowing down the upward trend of the light, avoiding the loss of light energy when the large field of view light reaches the rear system, facilitating the improvement of the illuminance of the edge field of view, and being beneficial for achieving a short total optical length.

[0059] In some embodiments, the focal length f6 of the sixth lens and the focal length f5 of the fifth lens satisfy: 0.5 < f6 / f5 < 0.8. Satisfying the above range, reasonably distributing the focal lengths of the fifth lens and the sixth lens is beneficial to reducing various aberrations of the second group, thereby being beneficial to the aberration balance of the optical system during the continuous zooming process between the wide-angle state and the telephoto state, enabling the zoom system to have good imaging quality. More specifically, 0.53 < f6 / f5 < 0.77.

[0060] In some embodiments, the focal length f6 of the sixth lens and the effective focal length f of the zoom lens satisfy: -1.7 < f6 / f < -1; the image-side curvature radius R12 of the sixth lens and the effective focal length f of the zoom lens satisfy: 0.55 < R12 / f < 3.5. Meeting the above ranges and setting the sixth lens to have a negative refractive power and an image side with a concave surface can effectively balance various aberrations generated by the front lens group. At the same time, it is beneficial to increase the divergence degree of light, increase the area of light entering the imaging surface, achieve large-format imaging of the lens, and improve the imaging quality of the zoom lens. More specifically, -1.62 < f6 / f < -1; 0.59 < R12 / f < 3.48.

[0061] In some embodiments, the combined focal length f12 of the first lens and the second lens and the effective focal length f of the zoom lens satisfy: -2.6 < f12 / f < -1.6. Meeting the above range and reasonably setting the focal length in front of the aperture is beneficial to diverging light and increasing the field of view angle of the zoom lens. More specifically, -2.51 < f12 / f < -1.6.

[0062] In some embodiments, the focal length f1234 of the first group and the focal length f56 of the second group satisfy: -0.9 < f1234 / f56 < -0.8. Meeting the above range and reasonably distributing the focal length relationship between the first group and the second group is beneficial for the first group and the second group to obtain a large zoom ratio within a small movement range, thus facilitating the miniaturization of the zoom system. More specifically, -0.86 < f1234 / f56 < -0.81.

[0063] In some embodiments, the aperture value FNOT of the zoom lens in the telephoto state and the aperture value FNOW of the zoom lens in the wide-angle state satisfy: 0.15 < FNOT - FNOW < 0.4. Meeting the above range is beneficial to narrowing the aperture gap between the wide-angle state and the telephoto state, thus ensuring good imaging quality of the zoom lens in different scenarios. More specifically, 0.17 < FNOT - FNOW < 0.38.

[0064] In some embodiments, the overall optical length TTLT of the zoom lens in the telephoto state and the overall optical length TTLW of the zoom lens in the wide-angle state satisfy: 1.05 < TTLT / TTLW < 1.2. Meeting the above range can obtain a large zoom ratio while being beneficial to the compactness of the zoom system. More specifically, 1.08 < TTLT / TTLW < 1.17.

[0065] In some embodiments, the maximum field of view angle FOVT of the zoom lens in the telephoto state and the maximum field of view angle FOVW of the zoom lens in the wide-angle state satisfy: 1.1 < FOVT / FOVW < 1.3. Meeting the above range is beneficial to achieving a large field of view angle of the zoom lens. More specifically, 1.13 < FOVT / FOVW < 1.26.

[0066] In some embodiments, the distance CT45 between the first group and the second group on the optical axis and the zoom ratio τ of the zoom lens satisfy: 0.02 mm < CT45 / τ < 0.34 mm; the distance CTt45 between the first group and the second group on the optical axis in the telephoto state and the distance CTw45 between the first group and the second group on the optical axis in the wide-angle state satisfy: 0.22 mm < CTw45 - CTt45 < 0.44 mm. Meeting the above range can achieve a balance between non-interference between the first group and the second group and achieving a large zoom ratio, and at the same time can also meet the requirements of miniaturization of the zoom system.

[0067] In some embodiments, the total optical length TTL of the zoom lens and the sum ∑CT of the central thicknesses of the first lens to the sixth lens along the optical axis satisfy: 0.51 < ∑CT / TTL < 0.67. Meeting the above range can effectively compress the total length of the zoom lens, and is beneficial to the structural design and production process of the zoom lens.

[0068] In some embodiments, the sum ∑CT of the central thicknesses of the first lens to the sixth lens along the optical axis and the effective focal length f of the zoom lens satisfy: 0.93 < ΣCT / f < 1.71. Meeting the above range can effectively correct the field curvature and distortion of the zoom lens and improve the imaging quality of the zoom lens.

[0069] In some embodiments, the focal length f2 of the second lens and the effective focal length f of the zoom lens satisfy: -5.5 < f2 / f < -2.5. Meeting the above range can share the negative refractive power of the first lens, which is beneficial to avoiding excessive light deflection caused by too concentrated optical power of the first lens and reducing the difficulty of aberration correction. More specifically, -5.21 < f2 / f < -2.72.

[0070] In some embodiments, the focal length f3 of the third lens and the effective focal length f of the zoom lens satisfy: -13 < f3 / f < 31; the object-side curvature radius R5 of the third lens and the effective focal length f of the zoom lens satisfy: 2.6 < R5 / f < 6; the image-side curvature radius R6 of the third lens and the effective focal length f of the zoom lens satisfy: 2.1 < R6 / f < 22. Meeting the above ranges can endow the third lens with positive or negative optical power and a suitable surface shape, which is beneficial to balancing the aberration between the front and rear lenses. More specifically, -12.37 < f3 / f < 30.31; 2.62 < R5 / f < 5.9; 2.19 < R6 / f < 21.29.

[0071] In some embodiments, the focal length f5 of the fifth lens and the effective focal length f of the zoom lens satisfy: -2.8 < f5 / f < -1.6. Meeting the above range can endow the fifth lens with a suitable negative refractive power, enabling light to enter the sixth lens at a relatively gentle angle and effectively correcting the aberration of the zoom lens. More specifically, -2.75 < f5 / f < -1.65.

[0072] In some embodiments, the object-side curvature radius R1 of the first lens and the image-side curvature radius R2 of the first lens satisfy: -0.4 < (R1 - R2) / (R1 + R2) < -0.1. Meeting the above range, by reasonably controlling the surface shape of the first lens, it helps to reduce the distortion generated by the first lens, reduce the difficulty of subsequent lens for distortion correction, and improve the imaging quality of the lens. More specifically, -0.33 < (R1 - R2) / (R1 + R2) < -0.11.

[0073] In some embodiments, the object-side curvature radius R3 of the second lens and the image-side curvature radius R4 of the second lens satisfy: 0.22 < (R3 - R4) / (R3 + R4) < 0.27. Meeting the above range, reasonably defining the shapes of the object side and the image side of the second lens can enable light to enter the rear-end lens at a relatively gentle angle, which helps to improve the overall stability of the zoom lens.

[0074] In some embodiments, the overall optical length TTL of the zoom lens and the distance CT45 between the first group and the second group on the optical axis satisfy: 11 < TTL / CT45 < 130; the overall optical length TTL of the zoom lens and the distance CT18 from the object side of the first lens to the image side of the fourth lens on the optical axis satisfy: 0.48 < CT18 / TTL < 0.6. Meeting the above ranges, while reducing the sensitivity, it can reserve sufficient space for the zooming of the zoom lens, ensuring that the zoom lens has high-performance imaging effects in both the wide-angle and telephoto states. More specifically, 11.17 < TTL / CT45 < 128.82.

[0075] In some embodiments, the zoom lens satisfies the conditional expressions: 2.1 mm < f < 3.5 mm; 1 mm < EPD < 1.5 mm; 5 mm < TTL < 6.5 mm; 1.9 < FNO < 2.5; 0.25 mm < BFL < 1.6 mm; 70° < FOV < 95°; 4.5 mm < IH < 5 mm. In the above conditional expressions, f represents the effective focal length of the zoom lens, FOV represents the maximum field of view angle of the zoom lens, EPD represents the entrance pupil diameter of the zoom lens, TTL represents the overall optical length of the zoom lens, FNO represents the aperture value of the zoom lens, IH represents the true image height corresponding to the maximum field of view angle of the zoom lens, and BFL represents the back focal length of the zoom lens. Meeting the above ranges, the zoom lens has at least one or more advantages such as miniaturization, large aperture, and large field of view angle. More specifically, 2.2 mm < f < 3.41 mm; 1.09 mm < EPD < 1.43 mm; 5.34 mm < TTL < 6.24 mm; 1.99 < Fno < 2.41; 0.27 mm < BFL < 1.55 mm; 73.11° < FOV < 91.41°; 4.54 mm < IH < 4.92 mm.

[0076] In some embodiments, the lens material of the zoom lens provided by the present invention can be glass or plastic. When the lens material is plastic, the production cost can be effectively reduced. Additionally, when the lens material is glass, due to the low dispersion characteristic of the glass itself, the geometric chromatic aberration of the optical system can be effectively corrected. Further, for the zoom lens provided by the present invention, the first lens can be a glass lens or a plastic lens, the fourth lens can be a glass lens, and the second lens, the third lens, the fifth lens, and the sixth lens can be plastic lenses, which not only enables the lens to have excellent imaging performance and good stability, but also makes the structure of the lens relatively compact, and can better achieve the balance between lens miniaturization and high image quality.

[0077] In some embodiments, the first lens, the second lens, the third lens, the fourth lens, the fifth lens, and the sixth lens can be spherical lenses or aspherical lenses. Compared with the spherical structure, the aspherical structure can effectively reduce the aberration of the optical system, thereby reducing the number of lenses and the size of the lenses, and better achieving lens miniaturization. More specifically, the first lens, the second lens, the third lens, the fourth lens, the fifth lens, and the sixth lens of the present invention can all be aspherical lenses, which can effectively reduce the aberration of the zoom lens, thereby reducing the number of lenses and the size of the lenses, and better achieving lens miniaturization.

[0078] In various embodiments of the present invention, when the lens is an aspherical lens, the surface shape of the aspherical lens satisfies the following equation: ; Among them, z is the sagitta, which is the distance from the vertex of the aspherical surface to the position along the optical axis at a height of h. c is the paraxial curvature of the surface, k is the conic coefficient, and A 2i is the aspherical surface coefficient of the 2i-th order.

[0079] The present invention will be further described below with multiple embodiments. In each embodiment, the thickness, curvature radius, and material selection of each lens in the zoom lens are somewhat different. For specific differences, refer to the parameter tables of each embodiment. The following embodiments are only preferred embodiments of the present invention, but the embodiments of the present invention are not limited only by the following embodiments. Any other changes, substitutions, combinations, or simplifications made without departing from the innovative points of the present invention should be regarded as equivalent replacement methods and are included in the protection scope of the present invention.

[0080] Embodiment 1 Please refer to Figure 1 and Figure 2 , which are respectively schematic structural diagrams of the zoom lens 100 provided in Embodiment 1 of the present invention in the wide-angle state and the telephoto state. The zoom lens 100 sequentially includes, along the optical axis from the object side to the imaging surface: a first group Q1 with positive optical power, a second group Q2 with negative optical power, and a filter G1.

[0081] The first group Q1 includes a first lens L1, a second lens L2, a diaphragm ST, a third lens L3, and a fourth lens L4.

[0082] Among them, the first lens L1 has negative optical power. Its object side surface S1 is concave near the optical axis, and its image side surface S2 is convex near the optical axis.

[0083] The second lens L2 has negative optical power. Its object side surface S3 is convex, and its image side surface S4 is concave; The third lens L3 has positive optical power. Its object side surface S5 is convex, and its image side surface S6 is concave near the optical axis; The fourth lens L4 has positive optical power. Its object side surface S7 is convex near the optical axis, and its image side surface S8 is convex; The second group Q2 sequentially includes, from the object side to the imaging surface: a fifth lens L5 and a sixth lens L6.

[0084] Among them, the fifth lens L5 has negative optical power. Its object side surface S9 is concave, and its image side surface S10 is convex near the optical axis; The sixth lens L6 has negative optical power. Its object side surface S11 is convex near the optical axis, and its image side surface S12 is concave near the optical axis.

[0085] In order to better reduce the volume and weight of the lens, the first lens L1 and the fourth lens L4 are glass aspherical lenses, and the second lens L2, the third lens L3, the fifth lens L5, and the sixth lens L6 are plastic aspherical lenses, which can effectively reduce costs, correct aberrations, and provide optical performance products with higher cost performance.

[0086] The relevant parameters of each lens in the zoom lens 100 in Embodiment 1 are shown in Table 1-1.

[0087] Table 1-1 The surface type parameters of the aspherical lenses of the zoom lens 100 in Embodiment 1 are shown in Table 1-2.

[0088] Table 1-2 Among them, CT45 in Table 1-1 above is the distance between the fourth lens L4 and the fifth lens L5 on the optical axis, and is also the distance between the first group Q1 and the second group Q2 on the optical axis. CT6G is the distance between the sixth lens L6 and the filter G1 on the optical axis, and is also the distance between the second group Q2 and the filter G1 on the optical axis. In this application, lossless zoom switching of the zoom lens in the wide-angle state and the telephoto state is achieved by changing the air gaps CT45 and CT6G.

[0089] Specifically, when the zoom lens zooms, the first group Q1 and the second group Q2 can move dynamically along the optical axis to complete the switching of the zoom lens between the wide-angle state and the telephoto state. During the dynamic movement process of mutual switching between the wide-angle state and the telephoto state, the zoom lens can achieve good imaging effects.

[0090] The parameters of the zoom lens 100 in Embodiment 1 in the wide-angle state and the telephoto state are shown in Table 1-3.

[0091] Table 1-3 As shown in Table 1-3, when the zoom lens 100 is in the wide-angle state, CT45 is 0.315 mm, and CT6G is 0.211 mm, corresponding to the optical structure of the zoom lens 100 in the wide-angle state. When the zoom lens 100 is in the telephoto state, CT45 is 0.083 mm, and CT6G is 0.949 mm, corresponding to the optical structure of the zoom lens 100 in the telephoto state.

[0092] Figure 3This is the F-Tan(Theta) distortion curve graph of the zoom lens 100 in the wide-angle state in this embodiment. It represents the F-Tan(Theta) distortion of light at different image heights on the imaging surface. The horizontal axis represents the distortion value (unit: %), and the vertical axis represents the half field of view angle (unit: °). It can be seen from the graph that the F-Tan(Theta) distortion of the zoom lens is controlled within -0.5% to 3%, indicating that the zoom lens 100 can correct distortion well.

[0093] Figure 4 This is the axial aberration curve graph of the zoom lens 100 in the wide-angle state in this embodiment. It represents the aberration of each wavelength on the optical axis at the imaging surface. The horizontal axis represents the axial aberration value (unit: mm), and the vertical axis represents the normalized pupil radius. It can be seen from the graph that the offset of the axial aberration is controlled within ±0.02 mm, indicating that the zoom lens 100 can correct axial aberration well.

[0094] Figure 5 This is the lateral chromatic aberration curve graph of the zoom lens 100 in the wide-angle state in this embodiment. It represents the chromatic aberration of each wavelength relative to the central wavelength (0.555 μm) at different image heights on the imaging surface. The horizontal axis represents the lateral chromatic aberration value of each wavelength relative to the central wavelength (unit: μm), and the vertical axis represents the normalized field of view angle. It can be seen from the graph that the lateral chromatic aberration between the longest wavelength and the shortest wavelength is controlled within ±2.5 μm, indicating that the zoom lens 100 can correct chromatic aberration well.

[0095] Figure 6 This is the F-Tan(Theta) distortion curve graph of the zoom lens 100 in the telephoto state in this embodiment. It represents the F-Tan(Theta) distortion of light at different image heights on the imaging surface. The horizontal axis represents the distortion value (unit: %), and the vertical axis represents the half field of view angle (unit: °). It can be seen from the graph that the F-Tan(Theta) distortion of the zoom lens is controlled within -3% to 0, indicating that the zoom lens 100 can correct distortion well.

[0096] Figure 7 This is the axial aberration curve graph of the zoom lens 100 in the telephoto state in this embodiment. It represents the aberration of each wavelength on the optical axis at the imaging surface. The horizontal axis represents the axial aberration value (unit: mm), and the vertical axis represents the normalized pupil radius. It can be seen from the graph that the offset of the axial aberration is controlled within ±0.03 mm, indicating that the zoom lens 100 can correct axial aberration well.

[0097] Figure 8This is the vertical chromatic aberration curve graph of the zoom lens 100 in the telephoto state in this embodiment, which represents the chromatic aberration of each wavelength relative to the central wavelength (0.555 μm) at different image heights on the imaging surface. The horizontal axis represents the vertical chromatic aberration value of each wavelength relative to the central wavelength (unit: μm), and the vertical axis represents the normalized field angle. It can be seen from the figure that the vertical chromatic aberration of the longest wavelength and the shortest wavelength is controlled within -1 μm to 5 μm, indicating that the zoom lens 100 can correct chromatic aberration well.

[0098] As can be seen from the above figures, the aberrations of the zoom lens in Embodiment 1 in the wide-angle state and the telephoto state are well balanced, and both have good optical imaging quality.

[0099] Embodiment 2 Please refer to Figure 9 and Figure 10 which are respectively the schematic structural diagrams of the zoom lens 200 provided in Embodiment 2 of the present invention in the wide-angle state and the telephoto state. This embodiment is generally the same as Embodiment 1, and the main differences are as follows: The first lens uses a plastic aspherical lens, and the object side surface S11 of the sixth lens L6 is a concave surface; the optical parameters such as the curvature radius, lens thickness, and spacing of each lens surface are different.

[0100] The relevant parameters of each lens in the zoom lens 200 in Embodiment 2 are shown in Table 2-1.

[0101] Table 2-1 The surface type parameters of the aspherical lens of the zoom lens 200 in Embodiment 2 are shown in Table 2-2.

[0102] Table 2-2 The parameters of the zoom lens 200 in this Embodiment 2 in the wide-angle state and the telephoto state are shown in Table 2-3.

[0103] Table 2-3 As shown in Table 2-3, when the zoom lens 200 is in the wide-angle state, CT45 is 0.367 mm, and CT6G is 0.145 mm, corresponding to the optical structure of the zoom lens 200 in the wide-angle state. When the zoom lens 200 is in the telephoto state, CT45 is 0.076 mm, and CT6G is 1.024 mm, corresponding to the optical structure of the zoom lens 200 in the telephoto state.

[0104] In this embodiment, the F-Tan(Theta) distortion curve graph, axial aberration curve graph, and vertical chromatic aberration curve graph of the zoom lens 200 in the wide-angle state are respectively as Figure 11 、Figure 12 , Figure 13 As shown in; the F-Tan(Theta) distortion curve graph, axial aberration curve graph, and lateral chromatic aberration curve graph of the zoom lens 200 in the telephoto state are respectively as Figure 14 , Figure 15 , Figure 16 shown.

[0105] From Figure 11 it can be seen that the F-Tan(Theta) distortion of the zoom lens 200 is controlled within 0 to 3%, indicating that the zoom lens 200 can correct distortion well. From Figure 12 it can be seen that the offset of the axial aberration is controlled within ±0.03 mm, indicating that the zoom lens 200 can correct the axial aberration well. From Figure 13 it can be seen that the lateral chromatic aberration between the longest wavelength and the shortest wavelength is controlled within ±2 μm, indicating that the zoom lens 200 can correct the chromatic aberration well.

[0106] From Figure 14 it can be seen that the F-Tan(Theta) distortion of the zoom lens 200 is controlled within -3% to 0, indicating that the zoom lens 200 can correct distortion well. From Figure 15 it can be seen that the offset of the axial aberration is controlled within ±0.03 mm, indicating that the zoom lens 200 can correct the axial aberration well. From Figure 16 it can be seen that the lateral chromatic aberration between the longest wavelength and the shortest wavelength is controlled within -1 μm to 5 μm, indicating that the zoom lens 200 can correct the chromatic aberration well.

[0107] From the above figures, it can be seen that the aberrations of the zoom lens 200 in the wide-angle state and the telephoto state in Embodiment 2 are well balanced, and both have good optical imaging quality.

[0108] Embodiment 3 Please refer to Figure 17 and Figure 18 , which are respectively the structural schematic diagrams of the zoom lens 300 provided in Embodiment 3 of the present invention in the wide-angle state and the telephoto state. This embodiment is generally the same as Embodiment 1, and the main differences are: the first lens uses a plastic aspherical lens, the third lens L3 has a negative optical power; the object side surface S11 of the sixth lens L6 is concave; the optical parameters such as the curvature radius, lens thickness, and spacing of each lens surface are different.

[0109] The relevant parameters of each lens in the zoom lens 300 in Embodiment 3 are shown in Table 3-1.

[0110] Table 3-1 The surface type parameters of the aspherical lens of the zoom lens 300 in Embodiment 3 are shown in Table 3-2.

[0111] Table 3-2 The parameters of the zoom lens 300 in this Embodiment 3 in the wide-angle state and the telephoto state are shown in Table 3-3.

[0112] Table 3-3 As shown in Table 3-3, when the zoom lens 300 is in the wide-angle state, CT45 is 0.442 mm, and CT6G is 0.0875 mm, corresponding to the optical structure of the zoom lens 300 in the wide-angle state. When the zoom lens 300 is in the telephoto state, CT45 is 0.073 mm, and CT6G is 1.153 mm, corresponding to the optical structure of the zoom lens 300 in the telephoto state.

[0113] In this embodiment, the F-Tan(Theta) distortion curve graph, the axial aberration curve graph, and the lateral chromatic aberration curve graph of the zoom lens 300 in the wide-angle state are respectively as Figure 19 , Figure 20 , Figure 21 shown; the F-Tan(Theta) distortion curve graph, the axial aberration curve graph, and the lateral chromatic aberration curve graph of the zoom lens 300 in the telephoto state are respectively as Figure 22 , Figure 23 , Figure 24 shown.

[0114] From Figure 19 it can be seen that the F-Tan(Theta) distortion of the zoom lens 300 is controlled within 0 to 3%, indicating that the zoom lens 300 can correct the distortion well. From Figure 20 it can be seen that the offset of the axial aberration is controlled within ±0.03 mm, indicating that the zoom lens 300 can correct the axial aberration well. From Figure 21 it can be seen that the lateral chromatic aberration between the longest wavelength and the shortest wavelength is controlled within ±3.5 μm, indicating that the zoom lens 300 can correct the chromatic aberration well.

[0115] From Figure 22 it can be seen that the F-Tan(Theta) distortion of the zoom lens 200 is controlled within -3% to 0, indicating that the zoom lens 300 can correct the distortion well. From Figure 23 it can be seen that the offset of the axial aberration is controlled within ±0.03 mm, indicating that the zoom lens 300 can correct the axial aberration well. From Figure 24It can be seen that the lateral chromatic aberration between the longest wavelength and the shortest wavelength is controlled within -1μm to 4μm, indicating that the zoom lens 300 can correct chromatic aberration well.

[0116] As can be seen from the above figures, the aberrations of the zoom lens 300 in the wide-angle state and the telephoto state in Embodiment 3 are well balanced, and both have good optical imaging quality.

[0117] Embodiment 4 Please refer to Figure 25 and Figure 26 , which are respectively schematic structural diagrams of the zoom lens 400 provided in Embodiment 4 of the present invention in the wide-angle state and the telephoto state. This embodiment is generally the same as Embodiment 1, and the main differences are: the first lens is a plastic aspherical lens, and the object side surface S11 of the sixth lens L6 is a concave surface; the optical parameters such as the curvature radius, lens thickness, and spacing of each lens surface are different.

[0118] The relevant parameters of each lens in the zoom lens 400 in Embodiment 4 are shown in Table 4-1.

[0119] Table 4-1 The surface type parameters of the aspherical lens of the zoom lens 400 in Embodiment 4 are shown in Table 4-2.

[0120] Table 4-2 The parameters of the zoom lens 400 in this Embodiment 4 in the wide-angle state and the telephoto state are shown in Table 4-3.

[0121] Table 4-3 As shown in Table 4-3, when the zoom lens 400 is in the wide-angle state, CT45 is 0.478mm, and CT6G is 0.0582mm, corresponding to the optical structure of the zoom lens 400 in the wide-angle state. When the zoom lens 400 is in the telephoto state, CT45 is 0.048mm, and CT6G is 1.325mm, corresponding to the optical structure of the zoom lens 400 in the telephoto state.

[0122] In this embodiment, the F-Tan(Theta) distortion curve diagram, axial aberration curve diagram, and lateral chromatic aberration curve diagram of the zoom lens 400 in the wide-angle state are respectively as Figure 27 , Figure 28 , Figure 29 shown; the F-Tan(Theta) distortion curve diagram, axial aberration curve diagram, and lateral chromatic aberration curve diagram of the zoom lens 400 in the telephoto state are respectively as Figure 30 ,Figure 31 , Figure 32 as shown.

[0123] As can be seen from Figure 27 , the F-Tan(Theta) distortion of the zoom lens 400 is controlled within 0 - 3%, indicating that the zoom lens 400 can correct the distortion well. As can be seen from Figure 28 , the offset of the axial aberration is controlled within ±0.03 mm, indicating that the zoom lens 400 can correct the axial aberration well. As can be seen from Figure 29 , the lateral chromatic aberration between the longest wavelength and the shortest wavelength is controlled within ±2.5 μm, indicating that the zoom lens 400 can correct the chromatic aberration well.

[0124] As can be seen from Figure 30 , the F-Tan(Theta) distortion of the zoom lens 400 is controlled within -3% - 0, indicating that the zoom lens 400 can correct the distortion well. As can be seen from Figure 31 , the offset of the axial aberration is controlled within ±0.03 mm, indicating that the zoom lens 400 can correct the axial aberration well. As can be seen from Figure 32 , the lateral chromatic aberration between the longest wavelength and the shortest wavelength is controlled within -2 μm - 6 μm, indicating that the zoom lens 400 can correct the chromatic aberration well.

[0125] As can be seen from the above figures, in Embodiment 4, the aberrations of the zoom lens 400 in the wide-angle state and the telephoto state are well balanced, and both have good optical imaging quality.

[0126] Please refer to Table 5 for the values corresponding to the parameters and conditional expressions in the optical characteristics of the above embodiments.

[0127] Table 5 In summary of the above embodiments, the zoom lens provided by the present invention has the following advantages: The zoom lens provided by the present invention can achieve optical lossless zoom well. By changing the air interval distance between different groups, the zoom lens can achieve zoom switching between the wide-angle state and the telephoto state, realizing a large zoom ratio, and achieving excellent effects such as compatibility between wide-angle shooting and telephoto shooting. It has one or more advantages such as miniaturization, large field of view angle, and high-quality imaging, greatly improving the user experience.

[0128] In the description of this specification, the description referring to terms such as "one embodiment", "some embodiments", "examples", "specific examples", or "some examples", etc. means that the specific features, structures, materials, or characteristics described in connection with the embodiment or example are included in at least one embodiment or example of the present invention. In this specification, the schematic representations of the above terms do not necessarily refer to the same embodiment or example. Moreover, the specific features, structures, materials, or characteristics described can be combined in a suitable manner in any one or more embodiments or examples.

[0129] The above-described embodiments merely represent several implementation manners of the present invention. The description is relatively specific and detailed, but it should not be construed as a limitation on the scope of the patent for the present invention. It should be noted that for those of ordinary skill in the art, without departing from the concept of the present invention, several modifications and improvements can still be made, and these all belong to the protection scope of the present invention. Therefore, the protection scope of the patent for the present invention shall be subject to the appended claims.

Claims

1. A zoom lens, comprising six lenses, characterized in that: It sequentially includes, from the object side to the imaging plane along the optical axis: a first group with positive optical power and a second group with negative optical power; The first group sequentially includes, from the object side to the imaging plane: a first lens, a second lens, a third lens, and a fourth lens; The first lens has negative optical power, its object side surface is concave near the optical axis, and its image side surface is convex near the optical axis; The second lens has negative optical power, its object side surface is convex, and its image side surface is concave; The third lens has optical power, its object side surface is convex, and its image side surface is concave near the optical axis; The fourth lens has positive optical power, its object side surface is convex near the optical axis, and its image side surface is convex; The second group sequentially includes a fifth lens and a sixth lens from the object side to the imaging plane; The fifth lens has negative optical power, its object side surface is concave, and its image side surface is convex near the optical axis; The sixth lens has negative optical power, and its image side surface is concave near the optical axis; The first group and the second group can move dynamically on the optical axis to achieve optical lossless zoom of the zoom lens between the wide-angle state and the telephoto state; Wherein, the effective focal length fT of the zoom lens in the telephoto state and the effective focal length fW of the zoom lens in the wide-angle state satisfy: 1.25 < fT / fW < 1.

5.

2. The zoom lens according to claim 1, wherein: The overall optical length TTL of the zoom lens and the effective focal length f of the zoom lens satisfy: 1.7 < TTL / f < 2.7; the overall optical length TTL of the zoom lens and the image height IH corresponding to the maximum field of view angle of the zoom lens satisfy: 1 < TTL / IH < 1.

4.

3. The zoom lens according to claim 1, wherein: The image height IH corresponding to the maximum field of view angle of the zoom lens, the effective focal length f of the zoom lens, and the maximum field of view angle FOV of the zoom lens satisfy: 0.96 < (IH / 2) / (f×Tan(FOV / 2)) < 1.04; the maximum field of view angle FOV of the zoom lens and the f-number FNO of the zoom lens satisfy: 30° < FOV / FNO < 46°.

4. The zoom lens according to claim 1, wherein: The image height IH corresponding to the maximum field of view angle of the zoom lens and the entrance pupil diameter EPD of the zoom lens satisfy: 3.3 < IH / EPD < 4.5; the image height IH corresponding to the maximum field of view angle of the zoom lens and the effective focal length f of the zoom lens satisfy: 1.4 < IH / f < 2.

2.

5. The zoom lens according to claim 1, wherein: The overall optical length TTLT of the zoom lens in the telephoto state and the zoom ratio τ of the zoom lens satisfy: 4mm < TTLT / τ < 5mm.

6. The zoom lens according to claim 1, wherein: The effective focal length f of the zoom lens and the focal length f1 of the first lens satisfy: -11 < f1 / f < -4.5; the curvature radius R1 of the object side surface of the first lens and the effective focal length f of the zoom lens satisfy: -1.5 < R1 / f < -0.6; the curvature radius R2 of the image side surface of the first lens and the effective focal length f of the zoom lens satisfy: -2.9 < R2 / f < -0.

8.

7. The zoom lens according to claim 1, wherein: The focal length f4 of the fourth lens and the effective focal length f of the zoom lens satisfy: 0.4 < f4 / f < 0.62; the focal length f6 of the sixth lens and the focal length f5 of the fifth lens satisfy: 0.5 < f6 / f5 < 0.

8.

8. The zoom lens according to claim 1, wherein: The focal length f6 of the sixth lens and the effective focal length f of the zoom lens satisfy: -1.7 < f6 / f < -1; the image-side curvature radius R12 of the sixth lens and the effective focal length f of the zoom lens satisfy: 0.55 < R12 / f < 3.

5.

9. The zoom lens according to claim 1, wherein: The combined focal length f12 of the first lens and the second lens and the effective focal length f of the zoom lens satisfy: -2.6 < f12 / f < -1.6; the focal length f1234 of the first group and the focal length f56 of the second group satisfy: -0.9 < f1234 / f56 < -0.

8.

10. The zoom lens according to claim 1, wherein: The aperture value FNOT of the zoom lens in the telephoto state and the aperture value FNOW of the zoom lens in the wide-angle state satisfy: 0.15 < FNOT - FNOW < 0.4; the overall optical length TTLT of the zoom lens in the telephoto state and the overall optical length TTLW of the zoom lens in the wide-angle state satisfy: 1.05 < TTLT / TTLW < 1.2; the maximum field of view FOVT of the zoom lens in the telephoto state and the maximum field of view FOVW of the zoom lens in the wide-angle state satisfy: 1.1 < FOVT / FOVW < 1.

3.

11. The zoom lens according to claim 1, wherein: The distance CT45 on the optical axis between the first group and the second group and the zoom ratio τ of the zoom lens satisfy: 0.02 mm < CT45 / τ < 0.34 mm; the distance CTt45 on the optical axis between the first group and the second group in the telephoto state and the distance CTw45 on the optical axis between the first group and the second group in the wide-angle state satisfy: 0.22 mm < CTw45 - CTt45 < 0.44 mm.

Images