zoom lens

Abstract

The present invention provides a zoom lens having a total of six lenses, which include, along the optical axis, from the object side to the imaging plane, a first group with positive optical power and a second group with negative optical power; the first group 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; the second lens has negative optical power; the third lens has optical power; and the fourth lens has positive optical power; the second group includes, from the object side to the imaging plane, a fifth lens and a sixth lens; the fifth lens has negative optical power; and the sixth lens has negative optical power; the zoom lens provided by the present invention can achieve optical lossless zoom between a wide-angle state and a telephoto state by dynamically moving the first group and the second group on the optical axis, thereby achieving excellent compatibility between wide-angle shooting and telephoto shooting.

Description

Technical Field

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

[0002] With the rapid development of portable electronic devices such as smartphones, consumer demand for camera equipment continues to increase. Limited by the need for thinner electronic devices, these devices typically use multiple fixed-focus lenses and digital cropping to achieve pseudo-zoom capabilities. This approach significantly compromises imaging quality and performance, failing to match the true optical zoom achieved by traditional cameras. This significantly reduces the zoom experience on portable devices like mobile phones. Therefore, the development of a compact, optically lossless zoom lens with excellent zoom performance is essential. Summary of the Invention

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

[0004] The technical solution adopted in the present invention is:

[0005] A zoom lens having six lenses, which, along the optical axis, from the object side to the imaging plane, sequentially comprise: a first group having positive optical power and a second group having negative optical power;

[0006] The first group includes, from the object side to the imaging surface, a first lens, a second lens, a third lens and a fourth lens;

[0007] The first lens has negative optical power, its object side surface is concave at the near optical axis, and its image side surface is convex at the near optical axis;

[0008] The second lens has negative optical power, its object side surface is convex, and its image side surface is concave;

[0009] The third lens has an optical power, an object-side surface thereof is convex, and an image-side surface thereof is concave near the optical axis;

[0010] The fourth lens has positive refractive power, its object side surface is convex at the near optical axis, and its image side surface is convex;

[0011] The second group includes, from the object side to the imaging plane, a fifth lens and a sixth lens;

[0012] The fifth lens has negative refractive power, its object side surface is concave, and its image side surface is convex near the optical axis;

[0013] The sixth lens has negative optical power, and its image side surface is concave at the near optical axis;

[0014] The first group and the second group can be dynamically moved on the optical axis to realize zoom switching of the zoom lens between a wide-angle state and a telephoto state;

[0015] 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 the following conditions: 1.25 <fT / fW<1.5。

[0016] Compared with the existing technology, the zoom lens provided by the present invention can well achieve optical lossless zoom. By changing the air spacing distance between different groups, the lens can be switched between wide-angle and telephoto states, achieving a larger zoom ratio, and achieving excellent compatibility between wide-angle and telephoto shooting. It has one or more advantages such as miniaturization, large field of view, and high-quality imaging, greatly improving the user experience. BRIEF DESCRIPTION OF THE DRAWINGS

[0017] The above and / or additional aspects and advantages of the present invention will become apparent and readily understood from the following description of the embodiments with reference to the accompanying drawings, in which:

[0018] Figure 1 FIG. 1 is a schematic structural diagram of the zoom lens in the wide-angle state according to Embodiment 1 of the present invention.

[0019] Figure 2 FIG. 1 is a schematic structural diagram of the zoom lens in the telephoto state according to Embodiment 1 of the present invention.

[0020] Figure 3 FIG. 4 is a graph showing the F-Tan (Theta) distortion curve of the zoom lens in Example 1 of the present invention at a wide angle. FIG.

[0021] Figure 4 1 is an axial aberration curve diagram of the zoom lens in the wide-angle state in Example 1 of the present invention.

[0022] Figure 5 FIG. 4 is a vertical chromatic aberration curve of the zoom lens in the wide-angle state in Example 1 of the present invention. FIG.

[0023] Figure 6 FIG. 4 is a graph showing the F-Tan (Theta) distortion curve of the zoom lens in the telephoto state in Example 1 of the present invention.

[0024] Figure 7 1 is an axial aberration curve diagram of the zoom lens in the telephoto state in Example 1 of the present invention.

[0025] Figure 8 FIG. 4 is a vertical axis chromatic aberration curve of the zoom lens in the telephoto state in Example 1 of the present invention.

[0026] Figure 9FIG. 2 is a schematic structural diagram of a zoom lens in a wide-angle state according to Embodiment 2 of the present invention.

[0027] Figure 10 Schematic diagram of the structure of the zoom lens in telephoto state according to Embodiment 2 of the present invention.

[0028] Figure 11 FIG. 4 is a graph showing the F-Tan (Theta) distortion curve of the zoom lens in the wide-angle state in Example 2 of the present invention.

[0029] Figure 12 1 is an axial aberration curve diagram of the zoom lens in the wide-angle state in Example 2 of the present invention.

[0030] Figure 13 FIG. 4 is a vertical chromatic aberration curve of the zoom lens in the wide-angle state in Example 2 of the present invention.

[0031] Figure 14 FIG. 4 is a graph showing the F-Tan (Theta) distortion curve of the zoom lens in telephoto state in Example 2 of the present invention.

[0032] Figure 15 1 is an axial aberration curve diagram of the zoom lens in the telephoto state in Example 2 of the present invention.

[0033] Figure 16 FIG. 4 is a vertical axis chromatic aberration curve of the zoom lens in the telephoto state according to Example 2 of the present invention.

[0034] Figure 17 FIG. 4 is a schematic structural diagram of a zoom lens in a wide-angle state according to Embodiment 3 of the present invention.

[0035] Figure 18 FIG. 4 is a schematic structural diagram of a zoom lens in a telephoto state according to Embodiment 3 of the present invention.

[0036] Figure 19 FIG. 4 is a graph showing the F-Tan (Theta) distortion curve of the zoom lens in the wide-angle state in Example 3 of the present invention.

[0037] Figure 20 1 is an axial aberration curve diagram of the zoom lens in the wide-angle state in Example 3 of the present invention.

[0038] Figure 21 FIG. 4 is a vertical chromatic aberration curve of the zoom lens in the wide-angle state in Example 3 of the present invention.

[0039] Figure 22 FIG. 4 is a graph showing the F-Tan (Theta) distortion curve of the zoom lens in telephoto state in Example 3 of the present invention.

[0040] Figure 23 1 is an axial aberration curve diagram of the zoom lens in the telephoto state in Example 3 of the present invention.

[0041] Figure 24 FIG. 4 is a vertical axis chromatic aberration curve of the zoom lens in the telephoto state in Example 3 of the present invention.

[0042] Figure 25 FIG. 4 is a schematic structural diagram of a zoom lens in a wide-angle state according to Embodiment 4 of the present invention.

[0043] Figure 26 FIG. 4 is a schematic structural diagram of a zoom lens in a telephoto state according to Embodiment 4 of the present invention.

[0044] Figure 27 FIG. 4 is a graph showing the F-Tan (Theta) distortion curve of the zoom lens in the wide-angle state in Example 4 of the present invention.

[0045] Figure 28 1 is an axial aberration curve diagram of the zoom lens in the wide-angle state in Example 4 of the present invention.

[0046] Figure 29 FIG. 4 is a vertical chromatic aberration curve of the zoom lens in the wide-angle state in Example 4 of the present invention.

[0047] Figure 30 FIG. 4 is a graph showing the F-Tan (Theta) distortion curve of the zoom lens in telephoto state according to Example 4 of the present invention.

[0048] Figure 31 4 is an axial aberration curve diagram of the zoom lens in the telephoto state in Example 4 of the present invention.

[0049] Figure 32 FIG. 4 is a vertical axis chromatic aberration curve of the zoom lens in the telephoto state according to Example 4 of the present invention.

[0050] The following specific embodiments will further illustrate the present invention in conjunction with the above-mentioned drawings. DETAILED DESCRIPTION

[0051] For a better understanding of 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 merely descriptions of 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.

[0052] It should be noted that in this specification, the terms "first," "second," "third," etc., are used solely to distinguish one feature from another and do not limit the features. Thus, the first lens discussed below could also be referred to as the second lens or the third lens without departing from the teachings of the present invention.

[0053] In the drawings, the thickness, size, and shape of the lenses are slightly exaggerated for ease of illustration. Specifically, the shapes of the spherical and aspherical surfaces shown in the drawings are provided by way of example. That is, the shapes of the spherical and aspherical surfaces are not limited to those shown in the drawings. The drawings are for illustration only and are not drawn strictly to scale.

[0054] In this article, the paraxial region refers to the area near the optical axis. If a lens surface is convex and the location of the convex surface is undefined, it means that the lens surface is convex at least in the paraxial region. If a lens surface is concave and the location of the concave surface is undefined, it means that the lens surface is concave at least in the paraxial region. The surface of each lens closest to the subject 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.

[0055] 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 preclude 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 list of 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.

[0056] Unless otherwise defined, all terms used herein (including technical and scientific terms) have the same meaning as commonly understood by those skilled in the art to which this application belongs. It should also be understood that terms (such as those defined in commonly used dictionaries) should be interpreted as having a meaning consistent with their meaning in the context of the relevant technology and will not be interpreted in an idealized or overly formal sense unless expressly defined as such herein.

[0057] It should be noted that, in the absence of conflict, the embodiments and features of the embodiments in this 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.

[0058] The zoom lens provided by the embodiment of the present invention has a total of six lenses, which sequentially include, from the object side to the imaging surface along the optical axis: a first group with a positive optical power and a second group with a negative optical power. The first group and the second group move dynamically on the optical axis to achieve zoom switching between the wide-angle state and the telephoto state of the zoom lens. 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 is concave near the optical axis, and its image side is convex near the optical axis; the second lens has a negative optical power, its object side is convex, and its image side is concave; the third lens may have a positive optical power or a negative optical power, its object side is convex, and its image side is concave near the optical axis; the fourth lens has a positive optical power, its object side is convex near the optical axis, and its image side 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 is concave, and its image side is convex near the optical axis; the sixth lens has a negative optical power, its object side may be concave or convex, and its image side is concave near the optical axis. The air gap on the optical axis between the first group and the second group and between the second group and the imaging surface of the present invention 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.

[0059] In some embodiments, the zoom lens may further include an aperture, and the aperture may be located between the second lens and the third lens. It can be understood that the aperture is used to limit the amount of incident light to change the brightness of the image. When the aperture is located between the second lens and the third lens, it is convenient for correcting the aperture aberration. It can be understood that when the first group moves dynamically on the optical axis, the aperture moves synchronously.

[0060] 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.

[0061] 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. Meeting the above range can obtain a large magnification ratio and excellent zoom performance. More specifically, 1.27 < fT / fW < 1.48.

[0062] 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 miniaturizing 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.

[0063] In some embodiments, the total optical length TTL of the zoom lens and the image height IH corresponding to the maximum field 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.

[0064] In some embodiments, the image height IH corresponding to the maximum field angle of the zoom lens, the effective focal length f of the zoom lens, and the maximum field 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.

[0065] In some embodiments, the maximum field 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 an appropriate field angle and f-number, can collect light at a large angle, and obtain good imaging quality. More specifically, 30.46° < FOV / FNO < 45.63°.

[0066] In some embodiments, the image height IH corresponding to the maximum field 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 entering 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.

[0067] In some embodiments, the image height IH corresponding to the maximum field 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.

[0068] 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. Here, 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. Meeting 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.

[0069] 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. Meeting the above range, by setting the first lens to have a negative refractive power and a suitable surface shape, is beneficial for the first lens to receive light at a larger angle and collect as much light as possible into the subsequent 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.

[0070] 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. Meeting the above conditions, by setting the fourth lens to have a positive optical power, is beneficial for light convergence, 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 of the large field of view light reaching the rear system, being beneficial for improving the illuminance of the edge field of view, and being beneficial for achieving a short total optical length.

[0071] 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. Meeting the above range, reasonably distributing the focal lengths of the fifth lens and the sixth lens is beneficial for reducing various aberrations of the second lens group, thus being beneficial for the aberration balance of the optical system during the continuous zoom 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.

[0072] 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, 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, and at the same time is conducive to increasing the divergence degree of light, increasing the area of light entering the imaging surface, achieving large-format imaging of the lens, and improving the imaging quality of the zoom lens. More specifically, -1.62 < f6 / f < -1; 0.59 < R12 / f < 3.48.

[0073] 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, by reasonably setting the focal length before the aperture, it is conducive to diverging light and increasing the field angle of the zoom lens. More specifically, -2.51 < f,12 / f < -1.6.

[0074] 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, by reasonably distributing the focal length relationship between the first group and the second group, it is conducive to the first group and the second group obtaining a larger zoom ratio within a smaller movement range, which is conducive to the miniaturization of the zoom system. More specifically, -0.86 < f1234 / f56 < -0.81.

[0075] 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, it is conducive to reducing the aperture gap between the wide-angle state and the telephoto state, thereby ensuring that the zoom lens has good imaging quality in different scenarios. More specifically, 0.17 < FNOT - FNOW < 0.38.

[0076] 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, a larger zoom ratio can be obtained while being conducive to the compactness of the zoom system. More specifically, 1.08 < TTLT / TTLW < 1.17.<(

[0077] In some embodiments, the maximum field angle FOVT of the zoom lens in the telephoto state and the maximum field 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 angle of the zoom lens. More specifically, 1.13 < FOVT / FOVW < 1.26.

[0078] In some embodiments, the spacing 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 spacing CTt45 between the first group and the second group on the optical axis in the telephoto state and the spacing 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.

[0079] 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.

[0080] 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.

[0081] 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 excessive concentration of the optical power of the first lens and reducing the difficulty of aberration correction. More specifically, -5.21 < f2 / f < -2.72.

[0082] 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 radius of curvature R5 of the object side surface of the third lens and the effective focal length f of the zoom lens satisfy: 2.6 < R5 / f < 6; the radius of curvature R6 of the image side surface 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 an appropriate surface shape, which is beneficial to balancing the aberrations 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.

[0083] 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 appropriate negative refractive power, enabling light to enter the sixth lens at a relatively gentle angle and effectively correcting the aberrations of the zoom lens. More specifically, -2.75 < f5 / f < -1.65.

[0084] In some embodiments, the radius of curvature R1 of the object side surface of the first lens and the radius of curvature R2 of the image side surface 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 lenses for distortion correction, and improve the imaging quality of the lens. More specifically, -0.33 < (R1 - R2) / (R1 + R2) < -0.11.

[0085] In some embodiments, the radius of curvature R3 of the object side surface of the second lens and the radius of curvature R4 of the image side surface 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 image side surfaces 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.

[0086] 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 surface of the first lens to the image side surface of the fourth lens on the optical axis satisfy: 0.48 < CT18 / TTL < 0.6. Meeting the above ranges, while reducing sensitivity, sufficient space can be reserved for the zooming of the zoom lens, ensuring high - performance imaging effects in both the wide - angle and telephoto states of the zoom lens. More specifically, 11.17 < TTL / CT45 < 128.82.

[0087] In some embodiments, the zoom lens satisfies the conditional formula: 2.1mm < f < 3.5mm; 1mm < EPD < 1.5mm; 5mm < TTL < 6.5mm; 1.9 < FNO < 2.5; 0.25mm < BFL < 1.6mm; 70° < FOV < 95°; 4.5mm < IH < 5mm. In the above conditional formula, f represents the effective focal length of the zoom lens, FOV represents the maximum field angle of the zoom lens, EPD represents the entrance pupil diameter of the zoom lens, TTL represents the total 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 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 angle. More specifically, 2.2mm < f < 3.41mm; 1.09mm < EPD < 1.43mm; 5.34mm < TTL < 6.24mm; 1.99 < Fno < 2.41; 0.27mm < BFL < 1.55mm; 73.11° < FOV < 91.41°; 4.54mm < IH < 4.92mm.

[0088] In some embodiments, the lens material in 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. When the lens material is glass, the geometric chromatic aberration of the optical system can be effectively corrected by the low dispersion characteristics of the glass itself. 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 of lens miniaturization and high image quality.

[0089] 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.

[0090] In each embodiment of the present invention, when the lens is an aspherical lens, the surface shape of the aspherical lens satisfies the following equation:

[0091] ;

[0092] Among them, z 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 surface, k is the quadratic surface coefficient, and A 2i is the 2i-th order aspheric surface coefficient.

[0093] The present invention is further described below using several embodiments. In each embodiment, the thickness, radius of curvature, and material selection of each lens in the zoom lens vary; for details, please refer to the parameter tables of each embodiment. The following embodiments are merely preferred embodiments of the present invention, but the present invention is not limited to these embodiments. Any other changes, substitutions, combinations, or simplifications that do not deviate from the novelties of the present invention shall be considered equivalent replacements and are included within the scope of protection of the present invention.

[0094] Example 1

[0095] See also Figure 1 and Figure 2 , which are schematic structural diagrams of the zoom lens 100 provided in Example 1 of the present invention in the wide-angle state and the telephoto state, respectively. The zoom lens 100 includes, along the optical axis from the object side to the imaging plane, a first group Q1 with positive optical power, a second group Q2 with negative optical power, and a filter G1.

[0096] The first group Q1 includes a first lens L1, a second lens L2, a stop ST, a third lens L3, and a fourth lens L4.

[0097] The first lens L1 has negative refractive power, its object-side surface S1 is concave at the near optical axis, and its image-side surface S2 is convex at the near optical axis.

[0098] The second lens L2 has negative refractive power, its object-side surface S3 is convex, and its image-side surface S4 is concave;

[0099] The third lens L3 has positive refractive power, its object-side surface S5 is convex, and its image-side surface S6 is concave near the optical axis;

[0100] The fourth lens L4 has positive refractive power, its object-side surface S7 is convex near the optical axis, and its image-side surface S8 is convex;

[0101] The second group Q2 includes, from the object side to the imaging plane, a fifth lens L5 and a sixth lens L6.

[0102] The fifth lens L5 has negative refractive power, its object-side surface S9 is concave, and its image-side surface S10 is convex near the optical axis.

[0103] The sixth lens L6 has negative refractive power, an object-side surface S11 of the sixth lens L6 is convex at the near optical axis, and an image-side surface S12 of the sixth lens L6 is concave at the near optical axis.

[0104] In order to better reduce the size and weight of the lens, the first lens L1 and the fourth lens L4 are glass aspheric lenses, and the second lens L2, the third lens L3, the fifth lens L5, and the sixth lens L6 are plastic aspheric lenses. This can effectively reduce costs, correct aberrations, and provide optical performance products with higher cost-effectiveness.

[0105] The relevant parameters of each lens in the zoom lens 100 in Example 1 are shown in Table 1-1.

[0106] Table 1-1

[0107]

[0108] The surface parameters of the aspheric lens of the zoom lens 100 in Example 1 are shown in Table 1-2.

[0109] Table 1-2

[0110]

[0111] In Table 1-1 above, CT45 is the distance on the optical axis between the fourth lens element L4 and the fifth lens element L5, which is also the distance on the optical axis between the first lens group Q1 and the second lens group Q2. CT6G is the distance on the optical axis between the sixth lens element L6 and the filter G1, which is also the distance on the optical axis between the second lens group Q2 and the filter G1. This application achieves lossless zoom switching between the wide-angle and telephoto positions of the zoom lens by changing the air gaps CT45 and CT6G.

[0112] Specifically, when the zoom lens zooms, the first group Q1 and the second group Q2 can dynamically move 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 switching between the wide-angle state and the telephoto state, the zoom lens can achieve good imaging effects.

[0113] Parameters of the zoom lens 100 of the first embodiment in the wide-angle state and the telephoto state are shown in Tables 1-3.

[0114] Table 1-3

[0115]

[0116] As shown in Table 1-3, when the zoom lens 100 is in the wide-angle position, CT45 is 0.315mm and CT6G is 0.211mm, corresponding to the optical structure of the zoom lens 100 in the wide-angle position. When the zoom lens 100 is in the telephoto position, CT45 is 0.083mm and CT6G is 0.949mm, corresponding to the optical structure of the zoom lens 100 in the telephoto position.

[0117] Figure 3 This is a graph of the F-Tan (Theta) distortion of the zoom lens 100 in this embodiment at wide angles. It shows the F-Tan (Theta) distortion of light rays at different image heights on the imaging plane. The horizontal axis represents the distortion value (unit: %), and the vertical axis represents the half field of view (unit: degrees). As can be seen from the graph, the F-Tan (Theta) distortion of the zoom lens is controlled within a range of -0.5% to 3%, demonstrating that the zoom lens 100 is capable of effectively correcting distortion.

[0118] Figure 4 This graph shows the axial aberration of the zoom lens 100 in the wide-angle position according to this embodiment. It shows the aberration along the optical axis at the imaging plane for each wavelength. The horizontal axis represents the axial aberration value (unit: mm), and the vertical axis represents the normalized pupil radius. As can be seen from the graph, the axial aberration offset is controlled within ±0.02 mm, indicating that the zoom lens 100 can effectively correct axial aberration.

[0119] Figure 5 This graph shows the vertical chromatic aberration of the zoom lens 100 in this embodiment at wide-angle mode. It shows the chromatic aberration of each wavelength relative to the center wavelength (0.555 μm) at different image heights on the imaging plane. The horizontal axis represents the vertical chromatic aberration of each wavelength relative to the center wavelength (unit: μm), and the vertical axis represents the normalized field of view. As can be seen from the graph, the vertical chromatic aberration for both the longest and shortest wavelengths is controlled within ±2.5 μm, demonstrating that the zoom lens 100 is capable of effectively correcting chromatic aberration.

[0120] Figure 6 This is a graph of the F-Tan (Theta) distortion of the zoom lens 100 in the telephoto position of this embodiment. It shows the F-Tan (Theta) distortion of light at different image heights on the imaging plane. The horizontal axis represents the distortion value (unit: %), and the vertical axis represents the half field of view (unit: °). As can be seen from the graph, the F-Tan (Theta) distortion of the zoom lens is controlled within a range of -3% to 0, indicating that the zoom lens 100 is capable of effectively correcting distortion.

[0121] Figure 7This graph shows the axial aberration of the zoom lens 100 in the telephoto position of this embodiment. It shows the aberration along the optical axis at the imaging plane for each wavelength. The horizontal axis represents the axial aberration value (unit: mm), and the vertical axis represents the normalized pupil radius. As can be seen from the graph, the axial aberration offset is controlled within ±0.03 mm, indicating that the zoom lens 100 can effectively correct axial aberration.

[0122] Figure 8 This graph shows the vertical chromatic aberration of the zoom lens 100 in the telephoto position of this embodiment. It shows the chromatic aberration of each wavelength relative to the center wavelength (0.555μm) at different image heights on the imaging plane. The horizontal axis represents the vertical chromatic aberration value of each wavelength relative to the center wavelength (unit: μm), and the vertical axis represents the normalized field of view. As can be seen from the graph, the vertical chromatic aberration for both the longest and shortest wavelengths is controlled within a range of -1μm to 5μm, demonstrating that the zoom lens 100 is capable of effectively correcting chromatic aberration.

[0123] It can be seen from the above figures that the aberrations of the zoom lens in Example 1 are well balanced in both the wide-angle state and the telephoto state, and both have good optical imaging quality.

[0124] Example 2

[0125] See also Figure 9 and Figure 10 , respectively, are schematic structural diagrams of the zoom lens 200 provided in Example 2 of the present invention in the wide-angle state and the telephoto state. This embodiment is substantially the same as Example 1, with the main differences being that: the first lens element is a plastic aspheric lens, the object-side surface S11 of the sixth lens element L6 is a concave surface; and the optical parameters such as the curvature radius of each lens surface, lens thickness, and spacing are different.

[0126] The relevant parameters of each lens in the zoom lens 200 in Example 2 are shown in Table 2-1.

[0127] Table 2-1

[0128]

[0129] The surface parameters of the aspheric lens of the zoom lens 200 in Example 2 are shown in Table 2-2.

[0130] Table 2-2

[0131]

[0132] Table 2-3 shows the parameters of the zoom lens 200 in the wide-angle state and the telephoto state according to the second embodiment.

[0133] Table 2-3

[0134]

[0135] As shown in Table 2-3, when the zoom lens 200 is in the wide-angle position, CT45 is 0.367mm and CT6G is 0.145mm, corresponding to the optical structure of the zoom lens 200 in the wide-angle position. When the zoom lens 200 is in the telephoto position, CT45 is 0.076mm and CT6G is 1.024mm, corresponding to the optical structure of the zoom lens 200 in the telephoto position.

[0136] In this embodiment, the F-Tan (Theta) distortion curve, the axial aberration curve, and the vertical chromatic aberration curve of the zoom lens 200 in the wide-angle state are shown in FIG. Figure 11 、 Figure 12 、 Figure 13 The F-Tan (Theta) distortion curve, axial aberration curve, and vertical chromatic aberration curve of the zoom lens 200 in the telephoto state are shown as follows: Figure 14 、 Figure 15 、 Figure 16 shown.

[0137] from Figure 11 It can be seen from the figure that the F-Tan (Theta) distortion of the zoom lens 200 is controlled within 0~3%, indicating that the zoom lens 200 can correct the distortion well. Figure 12 It can be seen from FIG 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. Figure 13 It can be seen from the figure that the vertical chromatic aberration of the longest wavelength and the shortest wavelength is controlled within ±2 μm, indicating that the zoom lens 200 can correct chromatic aberration well.

[0138] from Figure 14 It can be seen from the figure 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 the distortion well. Figure 15 It can be seen from FIG 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. Figure 16 It can be seen from the figure that the vertical axial chromatic aberration of the longest wavelength and the shortest wavelength is controlled within -1 μm~5 μm, indicating that the zoom lens 200 can correct chromatic aberration well.

[0139] It can be seen from the above figures that the aberrations of the zoom lens 200 in Example 2 are well balanced in both the wide-angle state and the telephoto state, and both have good optical imaging quality.

[0140] Example 3

[0141] See also Figure 17 and Figure 18, respectively, are schematic structural diagrams of a zoom lens 300 provided in Example 3 of the present invention in wide-angle and telephoto states. This embodiment is substantially the same as Example 1, with the main differences being that: the first lens element is a plastic aspheric lens; the third lens element L3 has negative optical power; the object-side surface S11 of the sixth lens element L6 is concave; and the optical parameters such as the curvature radius, lens thickness, and spacing of each lens surface are different.

[0142] The relevant parameters of each lens in the zoom lens 300 in Example 3 are shown in Table 3-1.

[0143] Table 3-1

[0144]

[0145] The surface parameters of the aspheric lens of the zoom lens 300 in Example 3 are shown in Table 3-2.

[0146] Table 3-2

[0147]

[0148] Table 3-3 shows the parameters of the zoom lens 300 in the wide-angle state and the telephoto state according to the third embodiment.

[0149] Table 3-3

[0150]

[0151] As shown in Table 3-3, when the zoom lens 300 is in the wide-angle position, CT45 is 0.442mm and CT6G is 0.0875mm, corresponding to the optical structure of the zoom lens 300 in the wide-angle position. When the zoom lens 300 is in the telephoto position, CT45 is 0.073mm and CT6G is 1.153mm, corresponding to the optical structure of the zoom lens 300 in the telephoto position.

[0152] In this embodiment, the F-Tan (Theta) distortion curve, the axial aberration curve, and the vertical chromatic aberration curve of the zoom lens 300 in the wide-angle state are shown in FIG. Figure 19 、 Figure 20 、 Figure 21 The F-Tan (Theta) distortion curve, axial aberration curve, and vertical chromatic aberration curve of the zoom lens 300 in the telephoto state are shown as follows: Figure 22 、 Figure 23 、 Figure 24 shown.

[0153] from Figure 19 It can be seen from the figure that the F-Tan (Theta) distortion of the zoom lens 300 is controlled within 0~3%, indicating that the zoom lens 300 can correct the distortion well. Figure 20 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 300 can correct the axial aberration well. Figure 21 As can be seen from the figure, the vertical chromatic aberration of the longest wavelength and the shortest wavelength is controlled within ±3.5 μm, indicating that the zoom lens 300 can correct chromatic aberration well.

[0154] from Figure 22 It can be seen from the figure 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. Figure 23 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 300 can correct the axial aberration well. Figure 24 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~4 μm, indicating that the zoom lens 300 can correct chromatic aberration well.

[0155] It can be seen from the above figures that the aberrations of the zoom lens 300 in Example 3 are well balanced in both the wide-angle state and the telephoto state, and both have good optical imaging quality.

[0156] Example 4

[0157] See also Figure 25 and Figure 26 , respectively, are schematic structural diagrams of a zoom lens 400 provided in Example 4 of the present invention in wide-angle and telephoto states. This embodiment is substantially the same as Example 1, with the main differences being that: the first lens element is a plastic aspheric lens; the object-side surface S11 of the sixth lens element L6 is a concave surface; and the optical parameters such as the curvature radius of each lens surface, lens thickness, and spacing are different.

[0158] The relevant parameters of each lens in the zoom lens 400 in Example 4 are shown in Table 4-1.

[0159] Table 4-1

[0160]

[0161] The surface parameters of the aspheric lens of the zoom lens 400 in Example 4 are shown in Table 4-2.

[0162] Table 4-2

[0163]

[0164] Table 4-3 shows the parameters of the zoom lens 400 in the wide-angle state and the telephoto state according to the fourth embodiment.

[0165] Table 4-3

[0166]

[0167] As shown in Table 4-3, when zoom lens 400 is in wide-angle mode, CT45 is 0.478mm and CT6G is 0.0582mm, corresponding to the optical structure of zoom lens 400 in wide-angle mode. When zoom lens 400 is in telephoto mode, CT45 is 0.048mm and CT6G is 1.325mm, corresponding to the optical structure of zoom lens 400 in telephoto mode.

[0168] In this embodiment, the F-Tan (Theta) distortion curve, the axial aberration curve, and the vertical chromatic aberration curve of the zoom lens 400 in the wide-angle state are shown in FIG. Figure 27 、 Figure 28 、 Figure 29 The F-Tan (Theta) distortion curve, axial aberration curve, and vertical chromatic aberration curve of the zoom lens 400 in the telephoto state are shown as follows: Figure 30 、 Figure 31 、 Figure 32 shown.

[0169] from Figure 27 It can be seen from the figure that 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. Figure 28 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 400 can correct the axial aberration well. Figure 29 As can be seen from the figure, the vertical chromatic aberration of the longest wavelength and the shortest wavelength is controlled within ±2.5 μm, indicating that the zoom lens 400 can correct chromatic aberration well.

[0170] from Figure 30 It can be seen from the figure that the F-Tan (Theta) distortion of the zoom lens 400 is controlled within -3% to 0, indicating that the zoom lens 400 can correct the distortion well. Figure 31 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 400 can correct the axial aberration well. Figure 32 It can be seen from the figure that the vertical chromatic aberration of the longest wavelength and the shortest wavelength is controlled within -2μm~6μm, indicating that the zoom lens 400 can correct chromatic aberration well.

[0171] It can be seen from the above figures that the aberrations of the zoom lens 400 in Example 4 are well balanced in both the wide-angle state and the telephoto state, and both have good optical imaging quality.

[0172] Please refer to Table 5, which shows the values corresponding to the parameters and conditional expressions in the optical characteristics of the above embodiments.

[0173] Table 5

[0174]

[0175] In summary of the above embodiments, the zoom lens provided by the present invention has the following advantages:

[0176] The zoom lens provided by the present invention can well achieve optical lossless zoom. By changing the air spacing distance between different groups, the zoom switch of the lens between wide-angle state and telephoto state can be realized, achieving a large zoom ratio, and achieving excellent compatibility between wide-angle shooting and telephoto shooting. It has one or more advantages such as miniaturization, large field of view, and high-quality imaging, greatly improving the user experience.

[0177] Throughout this specification, reference to terms such as "one embodiment," "some embodiments," "examples," "specific examples," or "some examples" means that a specific feature, structure, material, or characteristic described in conjunction with that embodiment or example is included in at least one embodiment or example of the present invention. In this specification, schematic representations of the above terms do not necessarily refer to the same embodiment or example. Furthermore, the specific features, structures, materials, or characteristics described may be combined in any suitable manner in any one or more embodiments or examples.

[0178] The above-described embodiments merely illustrate several implementations of the present invention, and while their descriptions are relatively specific and detailed, they should not be construed as limiting the scope of the present invention. It should be noted that a person skilled in the art would be able to make numerous variations and improvements without departing from the spirit of the present invention, all of which fall within the scope of protection of the present invention. Therefore, the scope of protection of the present invention shall be determined by the appended claims.

Claims

1. A zoom lens, comprising six lenses, characterized in that: It sequentially includes, from the object side to the imaging surface along the optical axis: a first group having a positive optical power and a second group having 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 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 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 angle of the zoom lens, the effective focal length f of the zoom lens, and the maximum field angle FOV of the zoom lens satisfy: 0.96 < (IH / 2) / (f×Tan(FOV / 2)) < 1.04; the maximum field 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 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 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 angle FOVT of the zoom lens in the telephoto state and the maximum field angle 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