Optical lens

Abstract

The invention provides an optical lens which sequentially comprises a first lens with positive focal power from an object side to an imaging surface along an optical axis, a second lens with negative focal power, a third lens with positive focal power and a fourth lens with negative focal power from the object side to the imaging surface, the object side surface of the second lens is a convex surface, and the image side surface of the second lens is a concave surface; the third lens has negative focal power; the fourth lens has negative focal power; the fifth lens has positive focal power, the object side surface of the fifth lens is a convex surface near the optical axis, and the image side surface of the fifth lens is a concave surface near the optical axis; the sixth lens has positive focal power, the object side surface of the sixth lens near the optical axis is a convex surface, and the image side surface of the sixth lens is a convex surface; and the object side surface of the seventh lens is a concave surface, and the image side surface of the seventh lens is a concave surface near the optical axis. According to the optical lens provided by the invention, through specific surface shape setting and reasonable focal power distribution, the imaging quality of the optical lens can be improved, the aberration can be reduced, and the optical lens has the advantage of excellent imaging quality.

Description

Technical Field

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

[0002] With the rapid growth of the consumer electronics market and the popularity of social, video, and live streaming software, people's requirements for the imaging quality of camera lenses are getting higher and higher. The camera lens has even become the primary consideration index when consumers purchase electronic devices. Especially as people become more and more active on online social platforms, higher requirements are put forward for the optical performance of electronic shooting devices. It is required that the imaging lens can take clear pictures in a relatively dark environment, and also has the characteristics of long focal length and small depth of field to better achieve the function of blurring the background and highlighting the subject, so as to take more textured pictures. At present, many imaging lenses have blurred image quality when shooting at night or in environments with poor light conditions such as indoors, and cannot simultaneously meet the problems of super large aperture, short total length and high pixel. Summary of the Invention

[0003] In view of the above problems, the purpose of the present invention is to provide an optical lens with excellent imaging quality.

[0004] The technical solution adopted by the present invention is as follows: An optical lens, comprising a total of seven lenses, which are sequentially arranged from the object side to the imaging surface along the optical axis: A first lens with positive optical power, the object side surface of which is convex and the image side surface of which is concave; A second lens with positive optical power, the object side surface of which is convex and the image side surface of which is concave; A third lens with negative optical power; A fourth lens with negative optical power; A fifth lens with positive optical power, the object side surface of which is convex near the optical axis and the image side surface of which is concave near the optical axis; A sixth lens with positive optical power, the object side surface of which is convex near the optical axis and the image side surface of which is convex; A seventh lens with negative optical power, the object side surface of which is concave and the image side surface of which is concave near the optical axis; Wherein, the combined focal length f12 of the first lens and the second lens and the combined focal length f3456 of the third lens, the fourth lens, the fifth lens and the sixth lens satisfy: 1.1 < f12 / f3456 < 1.3.

[0005] More preferably, the true image height IH corresponding to the maximum field of view angle of the optical lens, the effective focal length f of the optical lens, and the maximum field of view angle FOV of the optical lens satisfy: 1 < (IH / 2) / (f×Tan(FOV / 2)) < 1.03; the sum ∑CT of the central thicknesses of the first lens to the seventh lens on the optical axis respectively and the sum ∑AT of the spacing distances of any two adjacent lenses among the first lens to the seventh lens on the optical axis satisfy: 2.4 < ΣCT / ΣAT < 2.8.

[0006] More preferably, the maximum field of view angle FOV of the optical lens and the aperture value Fno of the optical lens satisfy: 54° < FOV / Fno < 56°; the overall optical length TTL of the optical lens and the aperture value Fno of the optical lens satisfy: 4.2mm < TTL / Fno < 4.4mm.

[0007] More preferably, the true image height IH corresponding to the maximum field of view angle of the optical lens and the effective focal length f of the optical lens satisfy: 1.9 < IH / f < 2; the true image height IH corresponding to the maximum field of view angle of the optical lens and the back focal length BFL of the optical lens satisfy: 10 < IH / BFL < 12.

[0008] More preferably, the effective focal length f of the optical lens and the focal length f1 of the first lens satisfy: 1 < f1 / f < 1.3; the effective focal length f of the optical lens and the focal length f7 of the seventh lens satisfy: -0.7 < f7 / f < -0.6.

[0009] More preferably, the effective focal length f of the optical lens and the focal length f2 of the second lens satisfy: 18 < f2 / f < 91; the effective focal length f of the optical lens and the focal length f3 of the third lens satisfy: -71 < f3 / f < -7.

[0010] More preferably, the effective focal length f of the optical lens and the focal length f4 of the fourth lens satisfy: -2.5 < f4 / f < -1.8; the effective focal length f of the optical lens and the focal length f5 of the fifth lens satisfy: 13 < f5 / f < 37.

[0011] More preferably, the effective focal length f of the optical lens and the focal length f6 of the sixth lens satisfy: 0.55 < f6 / f < 0.75; the curvature radius R11 of the object side of the sixth lens and the curvature radius R12 of the image side of the sixth lens satisfy: 5 < (R11 - R12) / (R11 + R12) < 9.

[0012] More preferably, the focal length f2 of the second lens and the focal length f3 of the third lens satisfy: -2.7 < f2 / f3 < -0.9; the distance CT23 between the second lens and the third lens on the optical axis, the central thickness CT2 of the second lens and the central thickness CT3 of the third lens satisfy: 0.6 < CT23 / (CT2 + CT3) < 1.

[0013] More preferably, the curvature radius R3 of the object side surface of the second lens and the curvature radius R4 of the image side surface of the second lens satisfy: -0.5 < (R3 - R4) / (R3 + R4) < 0; the curvature radius R13 of the object side surface of the seventh lens and the curvature radius R14 of the image side surface of the seventh lens satisfy: -2 < (R13 - R14) / (R13 + R14) < -1.5.

[0014] Compared with the prior art, the optical lens provided by the present invention can improve the imaging quality of the optical lens, reduce aberration, and improve the imaging quality of the optical lens by setting a specific surface shape and reasonably distributing the optical power, so that the lens has one or more advantages such as miniaturization, large aperture, large bottom and high pixel, and high imaging quality. BRIEF DESCRIPTION OF THE DRAWINGS

[0015] 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, in which: Figure 1 is a schematic structural diagram of the optical lens in Embodiment 1 of the present invention.

[0016] Figure 2 is a field curvature curve diagram of the optical lens in Embodiment 1 of the present invention.

[0017] Figure 3 is an F-Tan(Theta) distortion curve diagram of the optical lens in Embodiment 1 of the present invention.

[0018] Figure 4 is an axial aberration curve diagram of the optical lens in Embodiment 1 of the present invention.

[0019] Figure 5 is a lateral chromatic aberration curve diagram of the optical lens in Embodiment 1 of the present invention.

[0020] Figure 6 is a schematic structural diagram of the optical lens in Embodiment 2 of the present invention.

[0021] Figure 7 is a field curvature curve diagram of the optical lens in Embodiment 2 of the present invention.

[0022] Figure 8 is an F-Tan(Theta) distortion curve diagram of the optical lens in Embodiment 2 of the present invention.

[0023] Figure 9 It is the axial aberration curve graph of the optical lens in Embodiment 2 of the present invention.

[0024] Figure 10 It is the lateral chromatic aberration curve graph of the optical lens in Embodiment 2 of the present invention.

[0025] Figure 11 It is the structural schematic diagram of the optical lens in Embodiment 3 of the present invention.

[0026] Figure 12 It is the field curvature curve graph of the optical lens in Embodiment 3 of the present invention.

[0027] Figure 13 It is the F-Tan(Theta) distortion curve graph of the optical lens in Embodiment 3 of the present invention.

[0028] Figure 14 It is the axial aberration curve graph of the optical lens in Embodiment 3 of the present invention.

[0029] Figure 15 It is the lateral chromatic aberration curve graph of the optical lens in Embodiment 3 of the present invention.

[0030] Figure 16 It is the structural schematic diagram of the optical lens in Embodiment 4 of the present invention.

[0031] Figure 17 It is the field curvature curve graph of the optical lens in Embodiment 4 of the present invention.

[0032] Figure 18 It is the F-Tan(Theta) distortion curve graph of the optical lens in Embodiment 4 of the present invention.

[0033] Figure 19 It is the axial aberration curve graph of the optical lens in Embodiment 4 of the present invention.

[0034] Figure 20 It is the lateral chromatic aberration curve graph of the optical lens in Embodiment 4 of the present invention.

[0035] The following specific embodiments will further illustrate the present invention in conjunction with the above-mentioned drawings. Specific Embodiments

[0036] To better understand the present application, more detailed descriptions of various aspects of the present application will be made 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.

[0037] 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, 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.

[0038] In the drawings, for ease of illustration, the thickness, size, and shape of the lens 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 only examples and are not drawn to an exact scale.

[0039] In this context, 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.

[0040] It should also be understood that the terms "comprising", "including", "having", "containing" and / or "including having", when used in this specification, indicate the presence of the stated features, elements and / or components, but do not exclude the presence or addition of one or more other features, elements, components and / or combinations thereof. In addition, when an expression such as "at least one of..." appears after the list of listed features, it modifies the entire list of listed features, rather than an individual element in the list. In addition, when describing the 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.

[0041] 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.

[0042] 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 combination with the embodiments.

[0043] The optical lens provided by the embodiment of the present invention comprises a total of seven lenses, which sequentially include: a first lens, a second lens, a third lens, a fourth lens, a fifth lens, a sixth lens, and a seventh lens along the optical axis from the object side to the imaging surface.

[0044] In some embodiments, the first lens may have a positive optical power, with its object side being convex and its image side being concave. The second lens may have a positive optical power, with its object side being convex and its image side being concave. The third lens may have a negative optical power, and its object side may be concave or convex, and its image side may be concave or convex. The fourth lens may have a negative optical power, and its object side may be concave or convex, and its image side may be concave or convex. The fifth lens may have a positive optical power, with its object side being convex near the optical axis and its image side being concave near the optical axis. The sixth lens may have a positive optical power, with its object side being convex near the optical axis and its image side being convex. The seventh lens may have a negative optical power, with its object side being concave and its image side being concave near the optical axis.

[0045] In some embodiments, the optical lens may further include a diaphragm, and the diaphragm may be located between the object side and the first lens. It can be understood that the diaphragm is used to limit the amount of incident light to change the brightness of the image formation.

[0046] In some embodiments, the optical lens may further include a filter, and the filter may be disposed between the seventh 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 optical lens and affecting normal imaging.

[0047] In some embodiments, the combined focal length f12 of the first lens and the second lens and the combined focal length f3456 of the third lens, the fourth lens, the fifth lens, and the sixth lens satisfy: 1.1 < f12 / f3456 < 1.3. Meeting the above range, by reasonably setting the focal lengths of the front lens group and the rear lens group, it is beneficial to balance various aberrations generated by the optical system and improve the overall imaging quality. More specifically, 1.16 < f12 / f3456 < 1.26.

[0048] In some embodiments, the true image height IH corresponding to the maximum field of view angle of the optical lens, the effective focal length f of the optical lens, and the maximum field of view angle FOV of the optical lens satisfy: 1 < (IH / 2) / (f × Tan(FOV / 2)) < 1.03. Meeting the above range can control the optical lens to have a smaller distortion and improve the imaging quality of the optical lens.

[0049] In some embodiments, the sum ΣCT of the central thicknesses of the first lens to the seventh lens on the optical axis respectively and the sum ΣAT of the spacing distances between any two adjacent lenses of the first lens to the seventh lens on the optical axis satisfy: 2.4 < ΣCT / ΣAT < 2.8. Meeting the above range can make the structure of the lens more compact and is beneficial to realizing the miniaturization of the lens. More specifically, 2.45 < ΣCT / ΣAT < 2.65.

[0050] In some embodiments, the maximum field of view (FOV) of the optical lens and the aperture value (Fno) of the optical lens satisfy: 54° < FOV / Fno < 56°. Meeting the above range defines that the optical lens has an appropriate field of view and aperture value, can collect light at large angles, and obtain good imaging quality. More specifically, 54.9° < FOV / Fno < 55.9°.

[0051] In some embodiments, the total track length (TTL) of the optical lens and the aperture value (Fno) of the optical lens satisfy: 4.2 mm < TTL / Fno < 4.4 mm. Meeting the above range defines that the optical lens has a short total length and a large aperture. More specifically, 4.25 mm < TTL / Fno < 4.35 mm.

[0052] In some embodiments, the true image height (IH) corresponding to the maximum field of view of the optical lens and the effective focal length (f) of the optical lens satisfy: 1.9 < IH / f < 2. Meeting the above range helps to achieve a large image plane and improve the imaging quality of the optical lens. More specifically, 1.95 < IH / f < 1.99.

[0053] In some embodiments, the true image height (IH) corresponding to the maximum field of view of the optical lens and the back focal length (BFL) of the optical lens satisfy: 10 < IH / BFL < 12. Meeting the above range defines that the optical lens has an appropriate back focus, which is convenient for reasonably arranging the positions of each lens and reduces the processing and assembly difficulty. More specifically, 10.7 < IH / BFL < 11.11.

[0054] In some embodiments, the effective focal length (f) of the optical lens and the focal length (f1) of the first lens satisfy: 1 < f1 / f < 1.3. Meeting the above range, by setting the first lens to have a large positive refractive power, the incident light can be converged to a large extent, and more light can enter the system, which is beneficial to improving the light input of the lens, realizing the large aperture performance of the lens, and enabling the lens to achieve high-definition imaging in a relatively dark environment. More specifically, 1.11 < f1 / f < 1.18.

[0055] In some embodiments, the effective focal length (f) of the optical lens and the focal length (f7) of the seventh lens satisfy: -0.7 < f7 / f < -0.6. Meeting the above range can effectively balance various aberrations generated by the front lenses, and at the same time is beneficial to increasing the divergence degree of light, increasing the area of light entering the imaging plane, realizing the large target plane imaging of the lens, and improving the imaging quality of the optical lens. More specifically, -0.69 < f7 / f < -0.62.

[0056] In some embodiments, the effective focal length f of the optical lens and the focal length f2 of the second lens satisfy: 18 < f2 / f < 91; the effective focal length f of the optical lens and the curvature radius R3 of the object side surface of the second lens satisfy: 1.5 < R3 / f < 11; the effective focal length f of the optical lens and the curvature radius R4 of the image side surface of the second lens satisfy: 1.6 < R4 / f < 20. Meeting the above conditions, by reasonably setting the optical power and surface shape of the second lens, the deflection degree of light entering the second lens can be effectively reduced, which is beneficial to maintaining the miniaturization of the lens head. At the same time, the lens has a large aperture, increasing the light flux entering the lens. More specifically, 18.53 < f2 / f < 90.9; 1.67 < R3 / f < 10.32; 1.74 < R4 / f < 19.43.

[0057] In some embodiments, the effective focal length f of the optical lens and the focal length f3 of the third lens satisfy: -71 < f3 / f < -7. Meeting the above range can make the third lens have a negative refractive power, which can diverge light and correct the aberration generated by the front lens at the same time. More specifically, -70.32 < f3 / f < -7.36.

[0058] In some embodiments, the effective focal length f of the optical lens and the focal length f4 of the fourth lens satisfy: -2.5 < f4 / f < -1.8; meeting the above range can reasonably control the trend of light and avoid the problem of excessive lens sensitivity caused by excessive light deflection. More specifically, -2.43 < f4 / f < -1.9.

[0059] In some embodiments, the effective focal length f of the optical lens and the focal length f5 of the fifth lens satisfy: 13 < f5 / f < 37; the effective focal length f of the optical lens and the curvature radius R9 of the object side surface of the fifth lens satisfy: 0.7 < R9 / f < 1.2; the effective focal length f of the optical lens and the curvature radius R10 of the image side surface of the fifth lens satisfy: 0.7 < R10 / f < 1.3. Meeting the above range can control the spherical aberration contribution of the fifth lens within a reasonable range, making the lens have a high axial imaging resolution and being beneficial to achieving high-definition imaging of the lens. More specifically, 13.61 < f5 / f < 36.56; 0.79 < R9 / f < 1.15; 0.78 < R10 / f < 1.19.

[0060] In some embodiments, the effective focal length f of the optical lens and the focal length f6 of the sixth lens satisfy: 0.55 < f6 / f < 0.75; the radius of curvature R11 of the object side surface of the sixth lens and the radius of curvature R12 of the image side surface of the sixth lens satisfy: 5 < (R11 - R12) / (R11 + R12) < 9; the radius of curvature R11 of the object side surface of the sixth lens and the effective focal length f of the optical lens satisfy: 0.6 < R11 / f < 1; the radius of curvature R12 of the image side surface of the sixth lens and the effective focal length f of the optical lens satisfy: -0.7 < R12 / f < -0.5. Meeting the above ranges can make the sixth lens have a positive refractive power and a suitable surface shape, further converge the light rays, avoid excessive light deflection caused by over-concentration of positive optical power, and reduce the difficulty of correcting aberration. More specifically, 0.59 < f6 / f < 0.71; 5.3 < (R11 - R12) / (R11 + R12) < 8.28; 0.7 < R11 / f < 0.92; -0.64 < R12 / f < -0.55.

[0061] In some embodiments, the focal length f2 of the second lens and the focal length f3 of the third lens satisfy: -2.7 < f2 / f3 < -0.9; the distance CT23 between the second lens and the third lens on the optical axis, the central thickness CT2 of the second lens, and the central thickness CT3 of the third lens satisfy: 0.6 < CT23 / (CT2 + CT3) < 1. Meeting the above ranges can reduce the light deflection angle, make the light path more stable; at the same time, it can correct coma and field curvature, improve the flatness of imaging, and enhance the imaging quality of the optical lens. More specifically, -2.52 < f2 / f3 < -0.94; 0.6 < CT23 / (CT2 + CT3) < 1.

[0062] 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: -0.5 < (R3 - R4) / (R3 + R4) < 0. Meeting the above ranges can reasonably set the surface shape of the second lens, which is beneficial to gathering the light rays in the edge field of view, avoiding excessive light deflection angle so that the light rays can transition smoothly. More specifically, -0.32 < (R3 - R4) / (R3 + R4) < 0.

[0063] The radius of curvature R13 of the object side surface of the seventh lens and the radius of curvature R14 of the image side surface of the seventh lens satisfy: -2 < (R13 - R14) / (R13 + R14) < -1.5. Meeting the above ranges can reasonably define the shapes of the object side surface and the image side surface of the seventh lens, control the seventh lens to have an appropriate surface shape, help control the light path in the edge field of view, and improve the imaging quality of the edge field of view. More specifically, -1.84 < (R13 - R14) / (R13 + R14) < -1.65.

[0064] In some embodiments, the effective focal length f of the optical lens and the overall optical length TTL of the optical lens satisfy: 1.2 < TTL / f < 1.3. Satisfying the above range can effectively limit the length of the lens, which is beneficial to the miniaturization of the optical lens. More specifically, 1.27 < TTL / f < 1.29.

[0065] In some embodiments, the overall optical length TTL of the optical lens and the true image height IH corresponding to the maximum field of view angle of the optical lens satisfy: 0.6 < TTL / IH < 0.7. Satisfying the above range is beneficial to the balance of small volume and large image plane of the optical lens. More specifically, 0.64 < TTL / IH < 0.66.

[0066] In some embodiments, the overall optical length TTL of the optical lens and the sum ∑CT of the central thicknesses of the first lens to the seventh lens along the optical axis satisfy: 0.6 < ∑CT / TTL < 0.63. Satisfying the above range can effectively compress the overall length of the optical lens, and is beneficial to the structural design and production process of the optical lens.

[0067] In some embodiments, the sum ∑CT of the central thicknesses of the first lens to the seventh lens along the optical axis and the effective focal length f of the optical lens satisfy: 0.77 < ∑CT / f < 0.8. Satisfying the above range can effectively correct the field curvature and distortion of the optical lens and improve the imaging quality of the optical lens.

[0068] In some embodiments, the optical lens satisfies the following conditional expressions: 5 mm < f < 5.5 mm; 3.2 mm < EPD < 3.5 mm; 6.5 mm < TTL < 7 mm; 1.5 < Fno < 1.65; 0.9 mm < BFL < 1 mm; 85° < FOV < 90°; 10 mm < IH < 11 mm. In the above conditional expressions, f represents the effective focal length of the optical lens, EPD represents the entrance pupil diameter of the optical lens, TTL represents the overall optical length of the optical lens, Fno represents the aperture value of the optical lens, BFL represents the back focal length of the optical lens, FOV represents the maximum field of view angle of the optical lens, and IH represents the true image height corresponding to the maximum field of view angle of the optical lens. Satisfying the above range, the optical lens has at least one or more advantages such as miniaturization, large image plane, large aperture, and large field of view angle. More specifically, 5.26 mm < f < 5.34 mm; 3.32 mm < EPD < 3.41 mm; 6.76 mm < TTL < 6.83 mm; 1.56 < Fno < 1.61; 0.94 mm < BFL < 0.98 mm; 87.5° < FOV < 88.1°; 10.34 mm < IH < 10.55 mm.

[0069] In some embodiments, the lens material in the optical 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 characteristic of the glass itself. The first lens in the optical lens provided by the present invention uses a glass lens, and the second lens, the third lens, the fourth lens, the fifth lens, the sixth lens, and the seventh lens all use plastic lenses. Adopting a glass-plastic hybrid structure can improve the thermal stability performance.

[0070] In some embodiments, the first lens, the second lens, the third lens, the fourth lens, the fifth lens, the sixth lens, and the seventh lens can use 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 realizing the miniaturization of the lens. More specifically, the first lens, the second lens, the third lens, the fourth lens, the fifth lens, the sixth lens, and the seventh lens of the present invention can all use aspherical lenses, which can effectively reduce the aberration of the optical lens, thereby reducing the number of lenses and the size of the lenses, and better realizing the miniaturization of the lens.

[0071] In each embodiment of the present invention, when the lens uses an aspherical lens, the shapes of the aspherical surfaces of the optical lens satisfy the following equation: ; where z is the distance between the curved surface and the vertex of the curved surface in the optical axis direction, h is the distance from the optical axis to the curved surface, c is the curvature of the vertex of the curved surface, K is the conic coefficient, and B, C, D, E, F, G, H are the fourth-order, sixth-order, eighth-order, tenth-order, twelfth-order, fourteenth-order, and sixteenth-order surface coefficients respectively.

[0072] The present invention will be further described below with multiple embodiments. In each embodiment, the thickness, radius of curvature, and material selection of each lens in the optical lens are somewhat different. For specific differences, please refer to the parameter tables of each embodiment. The following embodiments are only the 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.

[0073] Embodiment 1 Please refer to Figure 1 , which shows a schematic structural diagram of the optical lens 100 provided in Embodiment 1 of the present invention. The optical lens 100 sequentially includes, along the optical axis from the object side to the imaging surface S17: a diaphragm ST, a first lens L1, a second lens L2, a third lens L3, a fourth lens L4, a fifth lens L5, a sixth lens L6, a seventh lens L7, and a filter G1.

[0074] Among them, the first lens L1 has a positive optical power, its object side S1 is convex, and its image side S2 is concave; The second lens L2 has a positive optical power, its object side S3 is convex, and its image side S4 is concave; The third lens L3 has a negative optical power, its object side S5 is convex near the optical axis, and its image side S6 is concave near the optical axis; The fourth lens L4 has a negative optical power, its object side S7 is concave, and its image side S8 is concave near the optical axis; The fifth lens L5 has a positive optical power, its object side S9 is convex near the optical axis, and its image side S10 is concave near the optical axis; The sixth lens L6 has a positive optical power, its object side S11 is convex near the optical axis, and its image side S12 is convex; The seventh lens L7 has a negative optical power, its object side S13 is concave, and its image side S14 is concave near the optical axis; Both the object side S15 and the image side S16 of the filter G1 are flat; The imaging surface S17 is flat.

[0075] The first lens L1, the second lens L2, the third lens L3, the fourth lens L4, the fifth lens L5, the sixth lens L6, and the seventh lens L7 all adopt plastic aspherical lenses.

[0076] The relevant parameters of each lens in the optical lens 100 in Embodiment 1 are shown in Table 1-1.

[0077] Table 1-1 The surface type parameters of the aspherical lenses of the optical lens 100 in Embodiment 1 are shown in Table 1-2.

[0078] Table 1-2 In this embodiment, the field curvature curve graph, the F-Tan(Theta) distortion curve graph, the axial aberration curve graph, and the lateral chromatic aberration curve graph of the optical lens 100 are respectively as Figure 2 , Figure 3 , Figure 4 , Figure 5 shown.

[0079] Figure 2The field curvature curve of Embodiment 1 is shown, which represents the field curvature of light rays with different wavelengths in the meridional image plane and the sagittal image plane. The horizontal axis represents the offset (unit: mm), and the vertical axis represents the field angle (unit: °). It can be seen from the figure that the field curvature of the meridional image plane and the sagittal image plane is controlled within -0.04 mm to 0.2 mm, indicating that the optical lens 100 can correct the field curvature well.

[0080] Figure 3 The F-Tan(Theta) distortion curve graph of Embodiment 1 is shown, which represents the F-Tan(Theta) distortion at different image heights on the imaging plane. The horizontal axis represents the F-Tan(Theta) distortion value (unit: %), and the vertical axis represents the semi-field angle (unit: °). It can be seen from the figure that the F-Tan(Theta) distortion of the optical lens 100 is controlled within 0 to 2%, indicating that the distortion of the optical lens 100 is well corrected.

[0081] Figure 4 The axial aberration curve graph of Embodiment 1 is shown, which represents the aberration on 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. It can be seen from the figure that the offset of the axial aberration is controlled within -0.06 mm to 0.04 mm, indicating that the optical lens 100 can correct the axial aberration better.

[0082] Figure 5 The lateral chromatic aberration curve graph of Embodiment 1 is shown, which represents the chromatic aberration at different image heights on the imaging plane for each wavelength relative to the central wavelength (0.555 μm). 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 angle. It can be seen from the figure that the lateral chromatic aberration between the longest wavelength and the shortest wavelength is controlled within ±2 μm, indicating that the optical lens 100 can correct the chromatic aberration extremely well.

[0083] Embodiment 2 Please refer to Figure 6 , which shows the structural schematic diagram of the optical lens 200 provided in Embodiment 2 of the present invention. Compared with Embodiment 1, the main differences are: the object side surface S5 of the third lens L3 is concave; the image side surface S6 of the third lens L3 is convex; the optical parameters such as the curvature radius of each lens surface and the lens thickness are different.

[0084] The relevant parameters of each lens in the optical lens 200 in Embodiment 2 are shown in Table 2-1.

[0085] Table 2-1 The surface type parameters of the aspherical lens of the optical lens 200 in Embodiment 2 are shown in Table 2-2.

[0086] Table 2-2 In this embodiment, the field curvature curve graph, F-Tan(Theta) distortion curve graph, axial aberration curve graph, and lateral chromatic aberration curve graph of the optical lens 200 are respectively as Figure 7 , Figure 8 , Figure 9 , Figure 10 shown.

[0087] It can be seen from Figure 7 that the field curvature of the meridional image plane and the sagittal image plane is controlled within -0.08 mm to 0.2 mm, indicating that the optical lens 200 can correct the field curvature well.

[0088] It can be seen from Figure 8 that the F-Tan(Theta) distortion of the optical lens 200 is controlled within 0 to 2%, indicating that the distortion of the optical lens 200 is well corrected.

[0089] It can be seen from Figure 9 that the offset of the axial aberration is controlled within -0.06 mm to 0.04 mm, indicating that the optical lens 200 can correct the axial aberration better.

[0090] It can be seen from Figure 10 that the lateral chromatic aberration of the longest wavelength and the shortest wavelength is controlled within ±2 μm, indicating that the optical lens 200 can correct the chromatic aberration extremely well.

[0091] Embodiment 3 Please refer to Figure 11 , which shows the structural schematic diagram of the optical lens 300 provided in Embodiment 3 of the present invention. Compared with Embodiment 1, the main differences are: the object side surface S5 of the third lens L3 is a concave surface; the object side surface S7 of the fourth lens L4 is a convex surface; the optical parameters such as the curvature radius and lens thickness of each lens surface are different.

[0092] The relevant parameters of each lens in the optical lens 300 in Embodiment 3 are shown in Table 3-1.

[0093] Table 3-1 The surface type parameters of the aspherical lens of the optical lens 300 in Embodiment 3 are shown in Table 3-2.

[0094] Table 3-2 In this embodiment, the field curvature curve graph, F-Tan(Theta) distortion curve graph, axial aberration curve graph, and lateral chromatic aberration curve graph of the optical lens 300 are respectively asFigure 12 , Figure 13 , Figure 14 , Figure 15 as shown in

[0095] From Figure 12 it can be seen that the field curvature of the meridional image plane and the sagittal image plane is controlled within -0.12 mm to 0.05 mm, indicating that the optical lens 300 can correct the field curvature well.

[0096] From Figure 13 it can be seen that the F-Tan(Theta) distortion of the optical lens 200 is controlled within 0 to 2%, indicating that the distortion of the optical lens 300 is well corrected.

[0097] From Figure 14 it can be seen that the offset of the axial aberration is controlled within -0.06 mm to 0.04 mm, indicating that the optical lens 300 can correct the axial aberration well.

[0098] From Figure 15 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 optical lens 300 can correct the chromatic aberration extremely well.

[0099] Embodiment 4 Please refer to Figure 16 , which shows a schematic structural diagram of the optical lens 400 provided in Embodiment 4 of the present invention. Compared with Embodiment 1, the main differences are: the object side surface S5 of the third lens L3 is a concave surface; the image side surface S8 of the fourth lens L4 is a convex surface; the optical parameters such as the curvature radius and lens thickness of each lens surface are different.

[0100] The relevant parameters of each lens in the optical lens 400 in Embodiment 4 are shown in Table 4-1.

[0101] Table 4-1 The surface type parameters of the aspherical lenses of the optical lens in Embodiment 4 are shown in Table 4-2.

[0102] Table 4-2 In this embodiment, the field curvature curve graph, F-Tan(Theta) distortion curve graph, axial aberration curve graph, and lateral chromatic aberration curve graph of the optical lens 400 are respectively as shown in Figure 17 , Figure 18 , Figure 19 , Figure 20 as shown.

[0103] From Figure 17It can be seen that the field curvature of the meridional image plane and the sagittal image plane is controlled within -0.08 mm to 0.16 mm, indicating that the optical lens 400 can well correct the field curvature.

[0104] From Figure 18 it can be seen that the F-Tan(Theta) distortion of the optical lens 400 is controlled within 0 to 2%, indicating that the distortion of the optical lens 400 is well corrected.

[0105] From Figure 19 it can be seen that the offset of the axial aberration is controlled within -0.06 mm to 0.04 mm, indicating that the optical lens 400 can better correct the axial aberration.

[0106] From Figure 20 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 optical lens 400 can excellently correct the chromatic aberration.

[0107] Please refer to Table 5 for the optical characteristics corresponding to the above embodiments, including the effective focal length f, the overall optical length TTL, the f-number Fno, the true image height IH corresponding to the maximum field of view angle, the maximum field of view angle FOV, and the values corresponding to each conditional expression in each embodiment.

[0108] Table 5 In summary of the above embodiments, the optical lens provided by the present invention, through specific surface shape settings and reasonable optical power distribution, makes the structure of the optical lens relatively compact, effectively shortening the overall length of the optical lens. At the same time, it has a relatively large image plane, which allows the lens to be paired with a large-bottom chip, with large pixel points, which is beneficial to reducing the signal-to-noise ratio and improving the imaging quality. The present invention also has a large aperture performance, which is beneficial to greatly increasing the light input of the lens, enabling high color reproduction, achieving high-definition imaging even in a dim environment, and being able to reasonably correct the overall aberration of the optical lens, having small distortion, high pixels, and improving the imaging quality of the optical lens.

[0109] In the description of this specification, the descriptions referring to the terms "one embodiment", "some embodiments", "example", "specific example", or "some examples", etc. mean 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.

[0110] The above-described embodiments merely represent several implementation manners of the present invention. The description thereof is relatively specific and detailed, but it should not be construed as a limitation to 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 variations and improvements can still be made, and these all fall within 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. An optical lens, comprising seven lenses, characterized in that: It sequentially includes, from the object side to the imaging surface along the optical axis: A first lens with positive optical power, whose object side is convex and whose image side is concave; A second lens with positive optical power, whose object side is convex and whose image side is concave; A third lens with negative optical power; A fourth lens with negative optical power; A fifth lens with positive optical power, whose object side is convex near the optical axis and whose image side is concave near the optical axis; A sixth lens with positive optical power, whose object side is convex near the optical axis and whose image side is convex; A seventh lens with negative optical power, whose object side is concave and whose image side is concave near the optical axis; Wherein, the combined focal length f12 of the first lens and the second lens and the combined focal length f3456 of the third lens, the fourth lens, the fifth lens and the sixth lens satisfy: 1.1 < f12 / f3456 < 1.

3.

2. The optical lens according to claim 1, characterized in that: The true image height IH corresponding to the maximum field of view angle of the optical lens, the effective focal length f of the optical lens and the maximum field of view angle FOV of the optical lens satisfy: 1 < (IH / 2) / (f×Tan(FOV / 2)) < 1.03; The sum ∑CT of the central thicknesses of the first lens to the seventh lens on the optical axis respectively and the sum ∑AT of the spacing distances between any two adjacent lenses of the first lens to the seventh lens on the optical axis satisfy: 2.4 < ΣCT / ΣAT < 2.

8.

3. The optical lens according to claim 1, characterized in that: The maximum field of view angle FOV of the optical lens and the aperture value Fno of the optical lens satisfy: 54° < FOV / Fno < 56°; The overall optical length TTL of the optical lens and the aperture value Fno of the optical lens satisfy: 4.2mm < TTL / Fno < 4.4mm.

4. The optical lens according to claim 1, characterized in that: The true image height IH corresponding to the maximum field of view angle of the optical lens and the effective focal length f of the optical lens satisfy: 1.9 < IH / f < 2; The true image height IH corresponding to the maximum field of view angle of the optical lens and the back focal length BFL of the optical lens satisfy: 10 < IH / BFL < 12.

5. The optical lens according to claim 1, characterized in that: The effective focal length f of the optical lens and the focal length f1 of the first lens satisfy: 1 < f1 / f < 1.3; The effective focal length f of the optical lens and the focal length f7 of the seventh lens satisfy: -0.7 < f7 / f < -0.

6.

6. The optical lens according to claim 1, characterized in that: The effective focal length f of the optical lens and the focal length f2 of the second lens satisfy: 18 < f2 / f < 91; The effective focal length f of the optical lens and the focal length f3 of the third lens satisfy: -71 < f3 / f < -7.

7. The optical lens according to claim 1, characterized in that: The effective focal length f of the optical lens and the focal length f4 of the fourth lens satisfy: -2.5 < f4 / f < -1.8; The effective focal length f of the optical lens and the focal length f5 of the fifth lens satisfy: 13 < f5 / f < 37.

8. The optical lens according to claim 1, characterized in that: The effective focal length f of the optical lens and the focal length f6 of the sixth lens satisfy: 0.55 < f6 / f < 0.75; The curvature radius R11 of the object side of the sixth lens and the curvature radius R12 of the image side of the sixth lens satisfy: 5 < (R11 - R12) / (R11 + R12) < 9.

9. The optical lens according to claim 1, characterized in that: The focal length f2 of the second lens and the focal length f3 of the third lens satisfy: -2.7 < f2 / f3 < -0.9; the distance CT23 between the second lens and the third lens on the optical axis, the central thickness CT2 of the second lens and the central thickness CT3 of the third lens satisfy: 0.6 < CT23 / (CT2 + CT3) < 1.

10. The optical lens according to claim 1, characterized in that: The curvature radius R3 of the object side surface of the second lens and the curvature radius R4 of the image side surface of the second lens satisfy: -0.5 < (R3 - R4) / (R3 + R4) < 0; the curvature radius R13 of the object side surface of the seventh lens and the curvature radius R14 of the image side surface of the seventh lens satisfy: -2 < (R13 - R14) / (R13 + R14) < -1.5.

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