Optical lens

Abstract

The present invention provides an optical lens, which comprises, in order from the object side to the imaging surface along the optical axis: a first lens having positive optical power, whose object side surface is convex and whose image side surface is concave; a second lens having positive optical power, whose object side surface is convex and whose image side surface is concave; a third lens having negative optical power; a fourth lens having negative optical power; a fifth lens having positive optical power, whose object side surface is convex at the near optical axis and whose image side surface is concave at the near optical axis; a sixth lens having positive optical power, whose object side surface is convex at the near optical axis and whose image side surface is convex; and a seventh lens having negative optical power, whose object side surface is concave and whose image side surface is concave at the near optical axis. The optical lens provided by the present invention can improve the imaging quality of the optical lens, reduce aberrations, and has the advantage of excellent imaging quality through a specific surface shape setting and reasonable optical power distribution.

Description

Technical Field

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

[0002] With the rapid growth of the consumer electronics market and the increasing popularity of social, video, and live-streaming apps, people are demanding increasingly high image quality from camera lenses. Camera lenses have even become a primary consideration when purchasing electronic devices. In particular, with people becoming increasingly active on online social platforms, higher demands are being placed on the optical performance of electronic cameras. Not only do these lenses need to be able to capture clear images in dim conditions, but they also require long focal lengths and narrow depths of field to better blur the background and highlight the subject, resulting in more textured images. Currently, many imaging lenses suffer from blurry images when shooting night scenes or in low-light conditions, such as indoors. They fail to simultaneously achieve the goals of a large aperture, a short overall length, and high pixel count. Summary of the Invention

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

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

[0005] An optical lens, comprising seven lenses, including the following elements in order from the object side to the imaging surface along the optical axis:

[0006] The first lens has positive refractive power, its object-side surface is convex and its image-side surface is concave;

[0007] a second lens having positive refractive power, whose object-side surface is convex and whose image-side surface is concave;

[0008] a third lens having negative optical power;

[0009] a fourth lens element having negative optical power;

[0010] a fifth lens element having positive refractive power, whose object-side surface is convex near the optical axis and whose image-side surface is concave near the optical axis;

[0011] a sixth lens element having positive refractive power, whose object-side surface is convex near the optical axis and whose image-side surface is convex;

[0012] The seventh lens element has a negative optical power, its object-side surface is concave, and its image-side surface is concave near the optical axis;

[0013] 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 the following conditions: 1.1 <f12 / f3456<1.3。

[0014] Further preferably, the true image height IH corresponding to the maximum field angle of the optical lens, the effective focal length f of the optical lens, and the maximum field angle FOV of the optical lens satisfy: 1 < (IH / 2) / (f×Tan(FOV / 2)) < 1.03; 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.

[0015] Further preferably, the maximum field 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.

[0016] Further preferably, the true image height IH corresponding to the maximum field 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 angle of the optical lens and the back focal length BFL of the optical lens satisfy: 10 < IH / BFL < 12.

[0017] Further 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.

[0018] Further 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.

[0019] Further 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.

[0020] Further 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.

[0021] Further 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.

[0022] Further 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.

[0023] 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 high pixel, and high imaging quality. BRIEF DESCRIPTION OF THE DRAWINGS

[0024] 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:

[0025] Figure 1 is a schematic structural diagram of the optical lens in Embodiment 1 of the present invention.

[0026] Figure 2 is the field curvature curve diagram of the optical lens in Embodiment 1 of the present invention.

[0027] Figure 3 is the F-Tan(Theta) distortion curve diagram of the optical lens in Embodiment 1 of the present invention.

[0028] Figure 4 is the axial aberration curve diagram of the optical lens in Embodiment 1 of the present invention.

[0029] Figure 5 is the lateral chromatic aberration curve diagram of the optical lens in Embodiment 1 of the present invention.

[0030] Figure 6 is a schematic structural diagram of the optical lens in Embodiment 2 of the present invention.

[0031] Figure 7 is the field curvature curve diagram of the optical lens in Embodiment 2 of the present invention.

[0032] Figure 8Graph showing the F-Tan (Theta) distortion of the optical lens in Example 2 of the present invention.

[0033] Figure 9 2 is an axial aberration curve diagram of the optical lens in Example 2 of the present invention.

[0034] Figure 10 Graph showing vertical axis chromatic aberration of the optical lens in Example 2 of the present invention.

[0035] Figure 11 Schematic diagram of the structure of the optical lens in Example 3 of the present invention.

[0036] Figure 12 4 is a field curvature curve diagram of the optical lens in Example 3 of the present invention.

[0037] Figure 13 Graph showing the F-Tan (Theta) distortion of the optical lens in Example 3 of the present invention.

[0038] Figure 14 4 is an axial aberration curve diagram of the optical lens in Example 3 of the present invention.

[0039] Figure 15 Graph showing vertical axis chromatic aberration of the optical lens in Example 3 of the present invention.

[0040] Figure 16 Schematic diagram of the structure of the optical lens in Example 4 of the present invention.

[0041] Figure 17 4 is a field curvature curve diagram of the optical lens in Example 4 of the present invention.

[0042] Figure 18 Graph showing the F-Tan (Theta) distortion of the optical lens in Example 4 of the present invention.

[0043] Figure 19 4 is an axial aberration curve diagram of the optical lens in Example 4 of the present invention.

[0044] Figure 20 Graph showing vertical axis chromatic aberration of the optical lens in Example 4 of the present invention.

[0045] The following specific embodiments will further illustrate the present invention in conjunction with the above-mentioned drawings. DETAILED DESCRIPTION

[0046] 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.

[0047] 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.

[0048] 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.

[0049] 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.

[0050] 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.

[0051] 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.

[0052] 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.

[0053] The optical lens provided by the embodiment of the present invention has 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.

[0054] In some embodiments, the first lens may have a positive optical power, its object side is convex, and its image side is concave. The second lens may have a positive optical power, its object side is convex, and its image side is concave. The third lens may have a negative optical power, 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, 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, its object side is convex near the optical axis, and its image side is concave near the optical axis. The sixth lens may have a positive optical power, its object side is convex near the optical axis, and its image side is convex. The seventh lens may have a negative optical power, its object side is concave, and its image side is concave near the optical axis.

[0055] In some embodiments, the optical lens may further include an aperture, and the aperture may be located between the object side and the first lens. It can be understood that the aperture is used to limit the amount of incident light to change the brightness of the image.

[0056] 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.

[0057] 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.

[0058] In some embodiments, the true image height IH corresponding to the maximum field angle of the optical lens, the effective focal length f of the optical lens, and the maximum field 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.

[0059] 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 conducive to the miniaturization of the lens. More specifically, 2.45 < ΣCT / ΣAT < 2.65.

[0060] In some embodiments, the maximum field angle 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 angle and aperture value, can collect light at a large angle, and obtain good imaging quality. More specifically, 54.9° < FOV / Fno < 55.9°.

[0061] In some embodiments, 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. Meeting the above range defines that the optical lens has a short overall length and a large aperture. More specifically, 4.25mm < TTL / Fno < 4.35mm.

[0062] In some embodiments, the true image height IH corresponding to the maximum field angle 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.

[0063] In some embodiments, the true image height IH corresponding to the maximum field angle 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, facilitates the reasonable arrangement of the positions of each lens, and reduces the processing and assembly difficulty at the same time. More specifically, 10.7 < IH / BFL < 11.11.

[0064] 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 greater extent, and more light can enter the system, which is conducive to increasing 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 darker environment. More specifically, 1.11 < f1 / f < 1.18.

[0065] 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 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 optical lens. More specifically, -0.69 < f7 / f < -0.62.

[0066] 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 conducive to maintaining the miniaturization of the lens head, and at the same time enables the lens to have a large aperture and increases 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.

[0067] 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 at the same time correct the aberrations generated by the front lenses. More specifically, -70.32 < f3 / f < -7.36.

[0068] 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 too large deflection degree of light. More specifically, -2.43 < f4 / f < -1.9.

[0069] 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, make the lens have a high axial imaging resolution ability, and is conducive 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.

[0070] 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 endow the sixth lens with positive refractive power and a suitable surface shape, further converge light rays, avoid excessive light deflection caused by overly concentrated 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.

[0071] 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 spacing 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.

[0072] 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 marginal field light rays and avoiding excessive light deflection angles so that the light rays can transition smoothly. More specifically, -0.32 < (R3 - R4) / (R3 + R4) < 0.

[0073] 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 of the marginal field, and improve the imaging quality of the marginal field. More specifically, -1.84 < (R13 - R14) / (R13 + R14) < -1.65.

[0074] 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. Meeting the above range can effectively limit the length of the lens and is beneficial to achieving miniaturization of the optical lens. More specifically, 1.27 < TTL / f < 1.29.

[0075] In some embodiments, the overall optical length TTL of the optical lens and the true image height IH corresponding to the maximum field angle of the optical lens satisfy: 0.6 < TTL / IH < 0.7. Meeting the above range is beneficial to achieving the balance of small volume and large image plane of the optical lens. More specifically, 0.64 < TTL / IH < 0.66.

[0076] 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. Meeting 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.

[0077] 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. Meeting the above range can effectively correct the field curvature and distortion of the optical lens and improve the imaging quality of the optical lens.

[0078] 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 angle of the optical lens, and IH represents the true image height corresponding to the maximum field angle of the optical lens. Meeting the above range, the optical lens has at least one or more advantages such as miniaturization, large image plane, large aperture, and large field 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.

[0079] 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, production costs can be effectively reduced. Alternatively, when the lens material is glass, the low dispersion characteristic of glass can be used to effectively correct the geometric chromatic aberration of the optical system. In the optical lens provided by the present invention, the first lens is a glass lens, and the second, third, fourth, fifth, sixth, and seventh lenses are all plastic lenses. The glass-plastic hybrid structure can improve thermal stability.

[0080] In some embodiments, the first lens, second lens, third lens, fourth lens, fifth lens, sixth lens, and seventh lens may be spherical lenses or aspherical lenses. Compared to spherical structures, aspherical structures can effectively reduce the aberrations of the optical system, thereby reducing the number and size of lenses, and better achieving lens miniaturization. More specifically, the first lens, second lens, third lens, fourth lens, fifth lens, sixth lens, and seventh lens of the present invention may all be aspherical lenses, which can effectively reduce the aberrations of the optical lens, thereby reducing the number and size of lenses, and better achieving lens miniaturization.

[0081] In various embodiments of the present invention, when the lens is an aspheric lens, the shapes of the aspheric surfaces of the optical lens satisfy the following equations:

[0082] ;

[0083] Where z is the distance between the surface and the vertex in the direction of the optical axis, h is the distance from the optical axis to the surface, c is the curvature of the surface vertex, K is the quadratic surface coefficient, and B, C, D, E, F, G, and H are the fourth-order, sixth-order, eighth-order, tenth-order, twelfth-order, fourteenth-order, and sixteenth-order surface coefficients, respectively.

[0084] The present invention is further illustrated below with reference to several embodiments. In each embodiment, the thickness, radius of curvature, and material selection of each lens in the optical 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 thereto. 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.

[0085] Example 1

[0086] See also Figure 1, shown is a schematic structural diagram of the optical lens 100 provided in Example 1 of the present invention. The optical lens 100 includes, along the optical axis from the object side to the imaging surface S17, an aperture 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.

[0087] The first lens L1 has positive refractive power, its object-side surface S1 is convex, and its image-side surface S2 is concave;

[0088] The second lens L2 has positive refractive power, its object-side surface S3 is convex, and its image-side surface S4 is concave;

[0089] The third lens L3 has negative refractive power, its object-side surface S5 is convex near the optical axis, and its image-side surface S6 is concave near the optical axis;

[0090] The fourth lens L4 has negative refractive power, its object-side surface S7 is concave, and its image-side surface S8 is concave near the optical axis;

[0091] The fifth lens L5 has positive refractive power, its object-side surface S9 is convex at the near optical axis, and its image-side surface S10 is concave at the near optical axis;

[0092] The sixth lens L6 has positive refractive power, its object-side surface S11 is convex near the optical axis, and its image-side surface S12 is convex;

[0093] The seventh lens L7 has negative refractive power, its object-side surface S13 is concave, and its image-side surface S14 is concave near the optical axis.

[0094] The object-side surface S15 and the image-side surface S16 of the filter G1 are both flat surfaces;

[0095] The imaging surface S17 is a plane.

[0096] 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 are all plastic aspherical lenses.

[0097] The relevant parameters of each lens in the optical lens 100 in Example 1 are shown in Table 1-1.

[0098] Table 1-1

[0099]

[0100] The surface parameters of the aspheric lens of the optical lens 100 in Example 1 are shown in Table 1-2.

[0101] Table 1-2

[0102]

[0103] In this embodiment, the field curvature curve, F-Tan (Theta) distortion curve, axial aberration curve, and vertical chromatic aberration curve of the optical lens 100 are shown as follows: Figure 2 、 Figure 3 、 Figure 4 、 Figure 5 shown.

[0104] Figure 2 The field curvature curves of Example 1 are shown, showing the field curvature of light of different wavelengths on the meridional and sagittal image planes. The horizontal axis represents the offset (unit: mm), and the vertical axis represents the field angle (unit: degrees). As can be seen from the figure, the field curvature of the meridional and sagittal image planes is controlled within a range of -0.04mm to 0.2mm, indicating that the optical lens 100 can effectively correct field curvature.

[0105] Figure 3 The following graph shows the F-Tan (Theta) distortion curve for Example 1, 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 half field of view angle (unit: °). As can be seen from the graph, the F-Tan (Theta) distortion of the optical lens 100 is controlled within 0-2%, indicating that the distortion of the optical lens 100 is well corrected.

[0106] Figure 4 The axial aberration curve of Example 1 is shown, which shows the aberration of each wavelength on the optical axis at the imaging plane. 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 figure, the offset of the axial aberration is controlled within -0.06mm to 0.04mm, indicating that the optical lens 100 is able to effectively correct the axial aberration.

[0107] Figure 5 A graph of vertical chromatic aberration for Example 1 is shown. It plots 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 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 ±2 μm, demonstrating that the optical lens 100 is capable of excellent chromatic aberration correction.

[0108] Example 2

[0109] See also Figure 6, shown is a schematic structural diagram of the optical lens 200 provided in Example 2 of the present invention. Compared with Example 1, this embodiment has the following main differences: the object-side surface S5 of the third lens L3 is a concave surface; the image-side surface S6 of the third lens L3 is a convex surface; and the optical parameters such as the curvature radius of each lens surface and the lens thickness are different.

[0110] The relevant parameters of each lens in the optical lens 200 in Example 2 are shown in Table 2-1.

[0111] Table 2-1

[0112]

[0113] The surface parameters of the aspheric lens of the optical lens 200 in Example 2 are shown in Table 2-2.

[0114] Table 2-2

[0115]

[0116] In this embodiment, the field curvature curve, F-Tan (Theta) distortion curve, axial aberration curve, and vertical chromatic aberration curve of the optical lens 200 are shown as follows: Figure 7 、 Figure 8 、 Figure 9 、 Figure 10 shown.

[0117] from Figure 7 It can be seen from the figure that the field curvature of the meridional image plane and the sagittal image plane is controlled within -0.08mm~0.2mm, indicating that the optical lens 200 can correct the field curvature well.

[0118] from Figure 8 It can be seen from the figure that the F-Tan (Theta) distortion of the optical lens 200 is controlled within 0~2%, indicating that the distortion of the optical lens 200 is well corrected.

[0119] from Figure 9 It can be seen from the figure that the offset of the axial aberration is controlled within -0.06mm~0.04mm, which shows that the optical lens 200 can correct the axial aberration well.

[0120] from Figure 10 It can be seen from the figure that the vertical axis chromatic aberration of the longest wavelength and the shortest wavelength is controlled within ±2μm, indicating that the optical lens 200 can correct chromatic aberration very well.

[0121] Example 3

[0122] See also Figure 11, shown is a schematic structural diagram of an optical lens 300 provided in Example 3 of the present invention. Compared with Example 1, this embodiment has the following main differences: 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; and the optical parameters such as the curvature radius of each lens surface and the lens thickness are different.

[0123] The relevant parameters of each lens in the optical lens 300 in Example 3 are shown in Table 3-1.

[0124] Table 3-1

[0125]

[0126] The surface parameters of the aspheric lens of the optical lens 300 in Example 3 are shown in Table 3-2.

[0127] Table 3-2

[0128]

[0129] In this embodiment, the field curvature curve, F-Tan (Theta) distortion curve, axial aberration curve, and vertical chromatic aberration curve of the optical lens 300 are shown as follows: Figure 12 、 Figure 13 、 Figure 14 、 Figure 15 shown.

[0130] from Figure 12 It can be seen from the figure that the field curvature of the meridional image plane and the sagittal image plane is controlled within -0.12mm~0.05mm, indicating that the optical lens 300 can correct the field curvature well.

[0131] from Figure 13 It can be seen from the figure that the F-Tan (Theta) distortion of the optical lens 200 is controlled within 0~2%, indicating that the distortion of the optical lens 300 is well corrected.

[0132] from Figure 14 It can be seen that the offset of the axial aberration is controlled within -0.06mm~0.04mm, indicating that the optical lens 300 can correct the axial aberration well.

[0133] from Figure 15 It can be seen from the figure that the vertical axis chromatic aberration of the longest wavelength and the shortest wavelength is controlled within ±2μm, indicating that the optical lens 300 can correct chromatic aberration very well.

[0134] Example 4

[0135] See also Figure 16, shown is a schematic structural diagram of an optical lens 400 provided in Example 4 of the present invention. Compared with Example 1, this embodiment has the following main differences: 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; and the optical parameters such as the curvature radius of each lens surface and the lens thickness are different.

[0136] The relevant parameters of each lens in the optical lens 400 in Example 4 are shown in Table 4-1.

[0137] Table 4-1

[0138]

[0139] The surface parameters of the aspheric lens of the optical lens in Example 4 are shown in Table 4-2.

[0140] Table 4-2

[0141]

[0142] In this embodiment, the field curvature curve, F-Tan (Theta) distortion curve, axial aberration curve, and vertical chromatic aberration curve of the optical lens 400 are shown as follows: Figure 17 、 Figure 18 、 Figure 19 、 Figure 20 shown.

[0143] from Figure 17 It can be seen that the field curvature of the meridional image plane and the sagittal image plane is controlled within -0.08mm~0.16mm, indicating that the optical lens 400 can correct the field curvature well.

[0144] from Figure 18 It can be seen from the figure that the F-Tan (Theta) distortion of the optical lens 400 is controlled within 0~2%, indicating that the distortion of the optical lens 400 is well corrected.

[0145] from Figure 19 It can be seen that the offset of the axial aberration is controlled within -0.06mm~0.04mm, indicating that the optical lens 400 can correct the axial aberration well.

[0146] from Figure 20 It can be seen from the figure that the vertical axis chromatic aberration of the longest wavelength and the shortest wavelength is controlled within ±2μm, indicating that the optical lens 400 can correct chromatic aberration very well.

[0147] Please refer to Table 5, which shows the optical characteristics corresponding to the above embodiments, including the effective focal length f, total optical length TTL, aperture value Fno, real image height IH corresponding to the maximum field of view angle, maximum field of view angle FOV, and the numerical value corresponding to each conditional expression in each embodiment.

[0148] Table 5

[0149]

[0150] In summary of the above embodiments, the optical lens provided by the present invention has a relatively compact structure through a specific surface shape setting and a reasonable distribution of optical power, effectively shortening the overall length of the optical lens. At the same time, it has a larger image surface, which allows the lens to be used with a large-bottom chip, with large pixels, 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 significantly increase the amount of light entering the lens, so that the color reproduction is high, and high-definition imaging can be achieved even in dim environments. It can also reasonably correct the overall aberration of the optical lens, with small distortion and high pixels, thereby improving the imaging quality of the optical lens.

[0151] 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.

[0152] 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. 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; The maximum field angle FOV of the optical lens and the f-number Fno of the optical lens satisfy: 54° < FOV / Fno < 56°; 2. The optical lens according to claim 1, wherein: The true image height IH corresponding to the maximum field angle of the optical lens, the effective focal length f of the optical lens and the maximum field 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 interval 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, 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: 1.16 < f12 / f3456 < 1.26; The maximum field angle FOV of the optical lens and the f-number Fno of the optical lens satisfy: 54.9° < FOV / Fno < 55.9°; The overall length TTL of the optical lens and the f-number Fno of the optical lens satisfy: 4.2mm < TTL / Fno < 4.4mm; 4. The optical lens according to claim 1, wherein: The true image height IH corresponding to the maximum field 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 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, wherein: 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, wherein: 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, wherein: 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, wherein: 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, wherein: 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, wherein: The curvature radius R3 of the object side of the second lens and the curvature radius R4 of the image side of the second lens satisfy: -0.5 < (R3 - R4) / (R3 + R4) < 0; the curvature radius R13 of the object side of the seventh lens and the curvature radius R14 of the image side of the seventh lens satisfy: -2 < (R13 - R14) / (R13 + R14) < -1.5.

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