Optical lens

Abstract

An optical lens provided by the present invention comprises a lens barrel, and a lens group and a spacer element group which are assembled in the lens barrel, the spacer element group at least comprises a first spacer element and a second spacer element, the first spacer element is located between a first lens and a second lens and is in partial contact with the image side surface of the first lens, and the second spacer element is located between the second lens and the second lens. The second spacing element is positioned between the second lens and the third lens and is in contact with the image side surface part of the second lens; the maximum height L of the lens cone and the effective focal length f of the optical lens meet the following conditions: 2.44 lt; l / flt; 3.15, 3.15; the effective focal length f2 of the second lens, the spacing distance EP12 between the first spacing element and the second spacing element in the direction of the optical axis, and the center thickness CT2 of the second lens meet the following conditions: 2.90 mm <-1 > lt; (CT2 / EP12) / f2lt; 6.56 mm <-1 >. According to the invention, the problem that miniaturization and assembly stability of an optical lens in the prior art are difficult to consider at the same time is solved.

Description

Technical Field

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

[0002] With the rapid progress of technology, the frequency of users' use of electronic products in different places and different scenarios has gradually increased. While the requirements for electronic products are developing towards portability, better imaging quality is also required. This requires electronic products to be thinner, lighter, and more miniaturized. The optical lenses mounted on electronic products are also developing towards being thinner, lighter, and more miniaturized while ensuring imaging quality. However, existing optical lenses are gradually developing towards miniaturization, but this results in a smaller internal space in the optical lens. The lenses located in the middle and rear positions of the optical lens are subject to greater stress, and there is a risk of easy fragmentation of the lenses located in the middle and rear positions during the assembly process. At the same time, there is also a risk of easy tilting of the lenses after assembly.

[0003] That is to say, there is a problem in the prior art that it is difficult to balance miniaturization and assembly stability of optical lenses. Summary of the Invention

[0004] The main object of the present invention is to provide an optical lens to solve the problem in the prior art that it is difficult to balance miniaturization and assembly stability of optical lenses.

[0005] To achieve the above object, according to one aspect of the present invention, there is provided an optical lens including a lens barrel, a lens group, and a spacer element group assembled in the lens barrel. The lens group sequentially includes a first lens, a second lens, and a third lens along the optical axis from the object side to the image side. Among them, the second lens has a positive optical power, the central thickness of the second lens is greater than the central thickness of the first lens, and the central thickness of the second lens is greater than the central thickness of the third lens; the spacer element group includes at least a first spacer element and a second spacer element. The first spacer element is located between the first lens and the second lens and is in partial contact with the image side surface of the first lens. The second spacer element is located between the second lens and the third lens and is in partial contact with the image side surface of the second lens; the maximum height L of the lens barrel and the effective focal length f of the optical lens satisfy: 2.44 < L / f < 3.15; the effective focal length f2 of the second lens, the interval distance EP12 between the first spacer element and the second spacer element in the direction of the optical axis, and the central thickness CT2 of the second lens satisfy: 2.90mm -1 <(CT2 / EP12) / f2 < 6.56mm -1 .

[0006] According to another aspect of the present invention, an optical lens is provided. The optical lens includes a lens barrel, a lens group and a spacer element group assembled in the lens barrel. The lens group sequentially includes a first lens, a second lens and a third lens along the optical axis from the object side to the image side. Among them, the second lens has a positive optical power; the spacer element group includes at least a first spacer element, a second spacer element and a third spacer element. The first spacer element is located between the first lens and the second lens and is in partial contact with the image side surface of the first lens. The second spacer element is located between the second lens and the third lens and is in partial contact with the image side surface of the second lens. The third spacer element is located on the image side of the third lens and is in partial contact with the image side surface of the third lens. The maximum height L of the lens barrel and the effective focal length f of the optical lens satisfy: 2.44 < L / f < 3.15; the distance Dr2r5 on the optical axis between the image side surface of the first lens and the object side surface of the third lens, the spacing distance EP12 between the first spacer element and the second spacer element in the direction of the optical axis, the central thickness CT3 of the third lens, and the spacing distance EP23 between the second spacer element and the third spacer element in the direction of the optical axis satisfy: 2.6 < Dr2r5 / EP12 + CT3 / EP23 < 3.45.

[0007] According to another aspect of the present invention, an optical lens is provided. The optical lens includes a lens barrel, a lens group and a spacer element group assembled in the lens barrel. The lens group sequentially includes a first lens, a second lens and a third lens along the optical axis from the object side to the image side. Among them, the second lens has a positive optical power, the image side surface of the first lens is concave, the image side surface of the second lens is convex, the object side surface of the third lens is convex, and the image side surface of the third lens is concave; the spacer element group includes at least a first spacer element and a second spacer element. The first spacer element is located between the first lens and the second lens and is in partial contact with the image side surface of the first lens. The second spacer element is located between the second lens and the third lens and is in partial contact with the image side surface of the second lens. The spacing distance EP12 between the first spacer element and the second spacer element in the direction of the optical axis and the central thickness CT2 of the second lens satisfy: 1.25 < CT2 / EP12 < 1.85; the curvature radius R3 of the object side surface of the second lens, the curvature radius R4 of the image side surface of the second lens, the inner diameter d1m of the image side surface of the first spacer element, and the inner diameter d2s of the object side surface of the second spacer element satisfy: 0.9 < (|R3| + |R4|) / (d2s + d1m) < 2.75.

[0008] Further, the outer peripheral surface of the lens barrel has a protruding structure, and the maximum outer diameter Y of the protruding structure satisfies: 3.1 mm < Y < 3.4 mm.

[0009] Further, the spacing distance EP12 between the first spacer element and the second spacer element in the direction of the optical axis, the central thickness CT2 of the second lens, and the inner diameter d2m of the image side surface of the second spacer element satisfy: 1.05 mm-1 <EP12 / CT2 / d2m < 1.75 mm -1 。

[0010] Further, the following conditions are satisfied among the radius of curvature R2 of the image side surface of the first lens, the radius of curvature R3 of the object side surface of the second lens, and the inner diameter d2s of the object side surface of the second spacer element: 1.25 < (R2 + R3) / d2s < 4.20.

[0011] Further, the following conditions are satisfied among the inner diameter d2m of the image side surface of the second spacer element, the outer diameter D2m of the image side surface of the second spacer element, and the inner diameter d1s of the object side surface of the first spacer element: 2.0 < (D2m - d1s) / d2m < 3.45.

[0012] Further, the spacer element group further includes a third spacer element. The third spacer element is located on the image side of the third lens and is in partial contact with the image side surface of the third lens. The following conditions are satisfied among the central thickness CT2 of the second lens, the central thickness CT3 of the third lens, and the central thickness CT1 of the first lens: 0.70 < CT2 / (CT3 + CT1) < 1.45; the following conditions are satisfied among the spacing distance EP12 between the first spacer element and the second spacer element in the optical axis direction, the distance EP01 between the object side end face of the lens barrel and the object side surface of the first spacer element in the optical axis direction, and the spacing distance EP23 between the second spacer element and the third spacer element in the optical axis direction: 0.25 < EP12 / (EP01 + EP23) < 0.5.

[0013] Further, the following conditions are satisfied among the inner diameter d2s of the object side surface of the second spacer element, the outer diameter D2m of the image side surface of the second spacer element, the outer diameter D1m of the image side surface of the first spacer element, and the inner diameter d1s of the object side surface of the first spacer element: 2.10 < D2m / D1m + d2s / d1s < 3.80.

[0014] Further, the following conditions are satisfied among the effective focal length f of the optical lens, half of the maximum field of view Semi - FOV of the optical lens, and the maximum height L of the lens barrel: 0.25 < f * tan(Semi - FOV) / L < 0.55.

[0015] Further, the spacer element group further includes a third spacer element. The third spacer element is located on the image side of the third lens and is in partial contact with the image side surface of the third lens. The following conditions are satisfied among the spacing distance EP23 between the second spacer element and the third spacer element in the optical axis direction, the outer diameter D2m of the image side surface of the second spacer element, and the inner diameter d2m of the image side surface of the second spacer element: 0.10 < EP23 / (D2m - d2m) < 0.28.

[0016] Further, the spacer element group further includes a third spacer element, the third spacer element is located on the image side of the third lens, and the third spacer element is in partial contact with the image side surface of the third lens. The inner diameter d0m of the image side end surface of the lens barrel and the minimum aperture diameter d3min of the third spacer element satisfy: 0.95 < d0m / d3min < 2.0.

[0017] Further, the distance EP01 in the optical axis direction between the object side end surface of the lens barrel and the object side surface of the first spacer element, the distance SG11 in the optical axis direction from the intersection point of the object side surface of the first lens and the optical axis to the object side surface of the structural region of the first lens, and the central thickness CT1 of the first lens satisfy: 0.75 < EP01 / (SG11 + CT1) < 2.50.

[0018] Further, the distance SG11 in the optical axis direction from the intersection point of the object side surface of the first lens and the optical axis to the object side surface of the structural region of the first lens, the central thickness CT1 of the first lens, and the central thickness CT2 of the second lens satisfy: 1.65 < (SG11 + CT2) / CT1 < 3.30.

[0019] Further, the image side surface of the first lens is concave; the image side surface of the second lens is convex; the object side surface of the third lens is convex, the image side surface of the third lens is concave, and the image side surface of the third lens has an inflection point.

[0020] Applying the technical solution of the present invention, the optical lens includes a lens barrel and a lens group and a spacer element group assembled in the lens barrel. The lens group sequentially includes a first lens, a second lens, and a third lens along the optical axis from the object side to the image side. Among them, the second lens has a positive optical power, the central thickness of the second lens is greater than the central thickness of the first lens, and the central thickness of the second lens is greater than the central thickness of the third lens; the spacer element group at least includes a first spacer element and a second spacer element. The first spacer element is located between the first lens and the second lens and is in partial contact with the image side surface of the first lens. The second spacer element is located between the second lens and the third lens and is in partial contact with the image side surface of the second lens; the maximum height L of the lens barrel and the effective focal length f of the optical lens satisfy: 2.44 < L / f < 3.15; the effective focal length f2 of the second lens, the interval distance EP12 in the optical axis direction between the first spacer element and the second spacer element, and the central thickness CT2 of the second lens satisfy: 2.90mm -1 <(CT2 / EP12) / f2 < 6.56mm -1 。

[0021] The optical lens of the present application consists of a lens barrel, three lenses, and at least two spacer elements. When 2.44 < L / f < 3.15 is satisfied between the maximum height L of the lens barrel and the effective focal length f of the optical lens, by restricting the relationship between the maximum height L of the lens barrel and the focal length of the optical lens, the space of the lens in the lens barrel can be constrained and the lens performance can be ensured. However, the development of the lens barrel towards miniaturization causes greater stress on the lens located in the middle and rear of the lens barrel, and it is easy to cause the lens located in the middle and rear of the lens barrel to break during the assembly process, resulting in poor assembly stability of the optical lens. Among the three lenses, the second lens is located in the middle and serves to support the first lens and the third lens. The stability of the second lens is even more important. If the assembly of the second lens is unstable, problems usually occur with both the first lens and the third lens. At the same time, the second lens is the lens with the thickest center, and the thickness ratio between the edge and the center affects the supporting stability. By restricting (CT2 / EP12) / f2 within a reasonable range, the overall shape of the second lens can be effectively limited, ensuring that the edge thickness, center thickness, and focal length of the second lens are within a reasonable range, maintaining the overall shape of the second lens while ensuring the light deflection ability of the second lens, and effectively avoiding the fragmentation problem caused by excessive stress during the assembly of the second lens; at the same time, it avoids the structure of the second lens affecting the structural layout of the third lens, which helps to ensure the stability and reliability of the assembly of the optical lens. The above two parametric equations together constitute an important parametric constraint in the design of the optical lens of the present application, which ensures that the optical lens can achieve good optical performance while maintaining a compact structure and assembly reliability. BRIEF DESCRIPTION OF THE DRAWINGS

[0022] The accompanying drawings forming a part of this application are used to provide a further understanding of the present invention. The schematic embodiments and descriptions thereof of the present invention are used to explain the present invention and do not constitute an improper limitation of the present invention. In the drawings:

[0023] Figure 1 The dimension marking diagram of the optical lens of an alternative embodiment of the present invention is shown;

[0024] Figure 2 The dimension marking diagram of the optical lens of another alternative embodiment of the present invention is shown;

[0025] Figure 3 The structural schematic diagram of the optical lens of Embodiment 1-1 of the present invention is shown;

[0026] Figure 4 The structural schematic diagram of the optical lens of Embodiment 1-2 of the present invention is shown;

[0027] Figure 5 and Figure 6 respectively show the axial chromatic aberration and astigmatism curves of the optical lens of Embodiment 1 of the present invention;

[0028] Figure 7 A schematic structural diagram of an optical lens according to Embodiment 2-1 of the present invention is shown;

[0029] Figure 8 A schematic structural diagram of an optical lens according to Embodiment 2-2 of the present invention is shown;

[0030] Fig. 9 and Fig.10 The axial chromatic aberration and astigmatism curves of the optical lens of the second embodiment of the present invention are respectively shown;

[0031] Fig.11 A schematic structural diagram of an optical lens according to Embodiment 3-1 of the present invention is shown;

[0032] Fig.12 A schematic structural diagram of an optical lens according to Embodiment 3-2 of the present invention is shown;

[0033] Fig.13 and Fig.14 The axial chromatic aberration and astigmatism curves of the optical lens of the third embodiment of the present invention are respectively shown;

[0034] Fig.15 A schematic structural diagram of an optical lens according to Embodiment 4-1 of the present invention is shown;

[0035] Fig.16 A schematic structural diagram of an optical lens according to Embodiment 4-2 of the present invention is shown;

[0036] Fig.17 and Fig.18 The axial chromatic aberration and astigmatism curves of the optical lens of the fourth embodiment of the present invention are respectively shown;

[0037] Fig.19 The force cloud diagram of the second lens and the third lens in an optical lens of an optional embodiment of the present invention is shown;

[0038] Fig. 20 A force cloud diagram of a second lens and a third lens in an optical lens of an example is shown;

[0039] Fig.21 A force cloud diagram of the second lens and the third lens in an optical lens of another example is shown.

[0040] The above drawings include the following reference numerals:

[0041] 10. Protruding structure; P0. Lens barrel; E1. First lens; S1. Object-side surface of the first lens; S2. Image-side surface of the first lens; P1. First spacing element; E2. Second lens; S3. Object-side surface of the second lens; S4. Image-side surface of the second lens; P2. Second spacing element; E3. Third lens; S5. Object-side surface of the third lens; S6. Image-side surface of the third lens; P3. Third spacing element. DETAILED DESCRIPTION

[0042] It should be noted that, in the absence of conflict, the embodiments and features in the embodiments of the present application can be combined with each other. The present invention will be described in detail below with reference to the accompanying drawings and in combination with the embodiments.

[0043] It should be noted that, unless otherwise specified, all technical and scientific terms used in this application have the same meanings as commonly understood by ordinary technicians in the technical field to which this application belongs.

[0044] In the present invention, unless otherwise specified, the directional words used, such as "up, down, top, bottom", usually refer to the directions shown in the drawings, or to the components themselves in the vertical, perpendicular or gravity directions; similarly, for ease of understanding and description, "inside and outside" refer to the inside and outside relative to the outline of each component itself, but the above-mentioned directional words are not used to limit the present invention.

[0045] It should be noted that in this specification, the expressions of first, second, third, etc. are only used to distinguish one feature from another feature, and do not represent any limitation on the features. Therefore, without departing from the teaching of the present application, the first lens discussed below may also be referred to as the second lens or the third lens.

[0046] In the drawings, the thickness, size and shape of the lenses have been slightly exaggerated for ease of illustration. Specifically, the shapes of the spherical or aspherical surfaces shown in the drawings are shown by way of example. That is, the shapes of the spherical or aspherical surfaces are not limited to the shapes of the spherical or aspherical surfaces shown in the drawings. The drawings are for illustration only and are not drawn strictly to scale.

[0047] In this text, the paraxial region refers to the region near the optical axis. If the lens surface is convex and the position of the convex surface is not defined, it means that the lens surface is convex at least in the paraxial region; if the lens surface is concave and the position of the concave surface is not defined, it means that the lens surface is concave at least in the paraxial region. The judgment of the surface shape in the paraxial region can be based on the judgment method of those with ordinary knowledge in this field, and the concavity and convexity are judged by the positive and negative values of the R value (R refers to the radius of curvature in the paraxial region, usually the R value on the lens database (lens data) in the optical software). Taking the object side surface as an example, when the R value is positive, it is judged as a convex surface, and when the R value is negative, it is judged as a concave surface; taking the image side surface as an example, when the R value is positive, it is judged as a concave surface, and when the R value is negative, it is judged as a convex surface. In this application, the left side is the object side and the right side is the image side.

[0048] In order to solve the problem that it is difficult to balance miniaturization and assembly stability in existing optical lenses, the present invention provides an optical lens.

[0049] As Figures 1 to 18 shown, the optical lens includes a lens barrel, a lens group and a spacer element group assembled in the lens barrel. The lens group sequentially includes a first lens, a second lens and a third lens along the optical axis from the object side to the image side. Among them, the second lens has a positive optical power, the central thickness of the second lens is greater than the central thickness of the first lens, and the central thickness of the second lens is greater than the central thickness of the third lens; the spacer element group includes at least a first spacer element and a second spacer element. The first spacer element is located between the first lens and the second lens and is in partial contact with the image side surface of the first lens. The second spacer element is located between the second lens and the third lens and is in partial contact with the image side surface of the second lens; the maximum height L of the lens barrel and the effective focal length f of the optical lens satisfy: 2.44 < L / f < 3.15; the effective focal length f2 of the second lens, the interval distance EP12 between the first spacer element and the second spacer element in the optical axis direction, and the central thickness CT2 of the second lens satisfy: 2.90mm -1 <(CT2 / EP12) / f2 < 6.56mm -1 。

[0050] The optical lens of the present application is composed of a lens barrel, three lenses and at least two spacer elements. When 2.44 < L / f < 3.15 is satisfied between the maximum height L of the lens barrel and the effective focal length f of the optical lens, by restricting the relationship between the maximum height L of the lens barrel and the focal length of the optical lens, the space of the lens in the lens barrel can be constrained and the lens performance can be ensured. However, the development of the lens barrel towards miniaturization causes the lens located in the middle and rear of the lens barrel to bear greater stress, and it is easy to cause the lens located in the middle and rear of the lens barrel to break during the assembly process, resulting in poor assembly stability of the optical lens. However, the second lens among the three lenses is located in the middle and plays a role in supporting the first lens and the third lens. The stability of the second lens is more important. If the assembly of the second lens is unstable, problems usually occur in both the first lens and the third lens. At the same time, the second lens is the thickest lens in the center, and the thickness ratio between the edge and the center affects the supporting stability. By restricting (CT2 / EP12) / f2 within a reasonable range in the present application, the overall shape of the second lens can be effectively limited, and the edge thickness, center thickness and focal length of the second lens can be ensured to be within a reasonable range, while ensuring the light deflection ability of the second lens and maintaining the overall shape of the second lens, effectively avoiding the fragmentation problem caused by excessive stress during the assembly of the second lens; at the same time, the structure of the second lens is prevented from affecting the structural layout of the third lens, which helps to ensure the stability and reliability of the assembly of the optical lens. The above two parameter formulas together constitute an important parameter constraint in the design of the optical lens of the present application, which ensures that the optical lens can achieve good optical performance while maintaining a compact structure and assembly reliability.

[0051] Table 1 shows the comparison of the stress nephograms of three optical lenses.

[0052]

[0053] Table 1

[0054] From Fig.19 and Fig. 20 and Fig.21 comparison, among lenses 1 to 3, the second lens and the third lens in lens 2 that satisfy 2.90mm -1 <(CT2 / EP12) / f2 < 6.56mm -1 bear the minimum maximum stress. Obviously, when (CT2 / EP12) / f2 is less than 2.9 or greater than 6.56, the maximum stress borne by the second lens in the optical lens becomes larger. Therefore, during the assembly process of lenses 1 and 3, the stress borne by the second lens and the third lens is relatively large under a certain amount of fit, and there is a risk of fragmentation. During the assembly process of lens 2, the stress borne by the second lens and the third lens becomes smaller under a certain amount of fit, and the risk of deformation and fragmentation is significantly reduced.

[0055] It should be noted that the present application limits (CT2 / EP12) / f2 within a reasonable range to control the overall shape of the second lens, ensure that the edge thickness, center thickness and focal length of the second lens are within a reasonable range, ensure the second lens's ability to deflect light while maintaining the overall shape of the second lens, and effectively avoid the problem of fragmentation caused by excessive stress during assembly of the second lens; at the same time, the structural layout of the third lens is guaranteed, which can simultaneously reduce the stress borne by the third lens, thereby reducing the stress borne by the second lens and the third lens, and improving the assembly stability of the optical lens. When (CT2 / EP12) / f2 meets the above range, the purpose of improving the assembly stability can be achieved without relying on the optical focal length of other lenses and the surface shape of the lens, and the optical focal length and surface shape of the lens are further optimization of the optical lens on this basis. The first lens and the third lens can be positive or negative according to the actual design requirements of the optical system, and the surface shape of each lens can be convex or concave according to the design requirements of the optical system. The optical system meets: 2.44 <L / f<3.15;2.90mm -1 <(CT2 / EP12) / f2<6.56mm -1 , it is possible to meet the miniaturization requirements while improving assembly stability.

[0056] For example, the first lens has positive focal power, the second lens has positive focal power, and the third lens has negative focal power. For another example, the first lens has negative focal power, the second lens has positive focal power, and the third lens has positive focal power. For another example, the first lens has negative focal power, the second lens has positive focal power, and the third lens has negative focal power. For another example, the image side surface of the first lens is concave; the image side surface of the second lens is convex; the object side surface of the third lens is convex, the image side surface of the third lens is concave, and the image side surface of the third lens has an inflection point. The optical lens can be simulated by software and / or tools such as ZEMAX and CODEV. In the process of simulation using the above-mentioned software and / or tools, the surface shape of each lens can be simulated and appropriately adjusted according to the surface shape of the software and / or tools used.

[0057] In some alternative embodiments, the outer peripheral surface of the lens barrel has a protruding structure, and the maximum outer diameter Y of the protruding structure satisfies: 3.1 mm < Y < 3.4 mm. By providing the protruding structure on the outer peripheral surface of the lens barrel, it is beneficial for the optical lens to be connected to other structures. At the same time, the provision of the protruding structure can improve the mechanical strength of the lens barrel, making it more resistant to external impacts and vibrations, effectively improving the reliability of the optical lens. In addition, the provision of the protruding structure can also improve the stability of the lens on the assembly tray during the assembly process; moreover, it provides sufficient space for chip attachment to ensure good compatibility between the optical lens and the chip. By restricting the maximum outer diameter of the protruding structure, while ensuring the structure of the lens barrel, the radial dimension of the lens barrel can be restricted, which is beneficial for the development of the optical lens towards miniaturization.

[0058] In some alternative embodiments, the spacing distance EP12 between the first spacer element and the second spacer element in the optical axis direction, the central thickness CT2 of the second lens, and the inner diameter d2m of the image side of the second spacer element satisfy: 1.05 mm -1 < EP12 / CT2 / d2m < 1.75 mm -1 . By restricting the relationship between the distance between the image side of the first spacer element and the object side of the second spacer element in the direction of the optical axis extension, the central thickness of the second lens, and the inner diameter of the image side of the second spacer element, while ensuring the structural strength of the second lens, it is ensured that the light can smoothly exit from the second spacer element after being deflected by the second lens, so as to avoid affecting the propagation of light, which is beneficial for reducing aberration and distortion and improving the imaging quality.

[0059] In some alternative embodiments, the radius of curvature R2 of the image side of the first lens, the radius of curvature R3 of the object side of the second lens, and the inner diameter d2s of the object side of the second spacer element satisfy: 1.25 < (R2 + R3) / d2s < 4.20. By constraining the relationship between the radius of curvature of the image side of the first lens, the radius of curvature of the object side of the second lens, and the inner diameter of the object side of the second spacer element, the deflection angle of the light when propagating between the first lens and the second lens can be ensured, avoiding large-angle deflection, which is beneficial for the imaging light to smoothly pass through the second spacer element. At the same time, the second spacer element can effectively block stray light, which is beneficial for improving the imaging quality of the optical lens.

[0060] In some alternative embodiments, the following condition is satisfied among the inner diameter d2m of the image side surface of the second spacer element, the outer diameter D2m of the image side surface of the second spacer element, and the inner diameter d1s of the object side surface of the first spacer element: 2.0 < (D2m - d1s) / d2m < 3.45. By restricting the relationship among the inner diameter of the object side surface of the first spacer element, the inner diameter of the image side surface of the second spacer element, and the outer diameter of the image side surface of the second spacer element, while ensuring that the imaging light passes smoothly through the first spacer element and the second spacer element, the outer diameter and the inner diameter of the second spacer can be restricted to ensure the width of the effective shielding surface of the second spacer element, thereby ensuring the stability of the abutment between the second lens and the second spacer element. At the same time, stray light with large-angle deflection can be absorbed to reduce the risk of stray light.

[0061] In some alternative embodiments, the spacer element group further includes a third spacer element. The third spacer element is located on the image side of the third lens and is in partial contact with the image side surface of the third lens. The following condition is satisfied among the central thickness CT2 of the second lens, the central thickness CT3 of the third lens, and the central thickness CT1 of the first lens: 0.70 < CT2 / (CT3 + CT1) < 1.45; the following condition is satisfied among the spacing distance EP12 between the first spacer element and the second spacer element in the optical axis direction, the distance EP01 between the object side end surface of the lens barrel and the object side surface of the first spacer element in the optical axis direction, and the spacing distance EP23 between the second spacer element and the third spacer element in the optical axis direction: 0.25 < EP12 / (EP01 + EP23) < 0.5. By restricting the distances between two adjacent spacer elements, the edge thicknesses of the lenses located between two adjacent spacer elements can be restricted. At the same time, by restricting the central thicknesses of the first lens, the second lens, and the third lens, the thickness ratio of the first lens to the third lens can be restricted. While reducing the molding difficulty of the lenses, the propagation path of light in the first lens to the third lens can be optimized, the scattering and absorption of light in the spacer elements can be reduced, and the optical performance of the optical lens can be further optimized, enabling the optical lens to have good imaging quality.

[0062] In some alternative embodiments, the following condition is satisfied among the inner diameter d2s of the object side surface of the second spacer element, the outer diameter D2m of the image side surface of the second spacer element, the outer diameter D1m of the image side surface of the first spacer element, and the inner diameter d1s of the object side surface of the first spacer element: 2.10 < D2m / D1m + d2s / d1s < 3.80. By controlling the relationship among the inner diameter and the outer diameter of the object side surface of the second spacer element and the inner diameter and the outer diameter of the object side surface of the first spacer element, while ensuring the stability of the abutment between the first lens and the second lens, the imaging light can pass smoothly through the first spacer element and the second spacer element. At the same time, the reasonable inner diameter and outer diameter of the spacer element can also block the excess light emitted from the first lens and the second lens and reduce the internal reflection stray light generated by the second lens, reducing the risk of stray light.

[0063] In some alternative embodiments, the following relationship is satisfied among the effective focal length f of the optical lens, half of the maximum field of view Semi-FOV of the optical lens, and the maximum height L of the lens barrel: 0.25 < f * tan(Semi-FOV) / L < 0.55. By restricting the relationship among the effective focal length of the optical lens, half of the maximum field of view of the optical lens, and the maximum height of the lens barrel, the balance among the effective focal length, the field of view, and the maximum height of the lens barrel of the optical lens can be effectively ensured, enabling the optical lens to take into account both image quality and miniaturization. Restricting f * tan(Semi-FOV) / L within the above range helps to reduce aberration, improve resolution and contrast while ensuring the size of the optical lens.

[0064] In some alternative embodiments, the spacer element group further includes a third spacer element. The third spacer element is located on the image side of the third lens and is in partial contact with the image side surface of the third lens. The following relationship is satisfied among the spacing distance EP23 between the second spacer element and the third spacer element in the optical axis direction, the outer diameter D2m of the image side surface of the second spacer element, and the inner diameter d2m of the image side surface of the second spacer element: 0.10 < EP23 / (D2m - d2m) < 0.28. By restricting the outer diameter and inner diameter of the image side surface of the second spacer element and the spacing between the second spacer element and the third spacer element, it helps to reduce the scattering and loss of light when passing through the spacer elements while ensuring the abutting stability between the second lens and the second spacer element, thereby maintaining the quality and clarity of the image. In addition, restricting EP23 / (D2m - d2m) within the above range can also ensure the relative position stability between the spacer elements, reduce the performance degradation caused by vibration or shock, and improve the reliability of the lens.

[0065] In some alternative embodiments, the spacer element group further includes a third spacer element. The third spacer element is located on the image side of the third lens and is in partial contact with the image side surface of the third lens. The following relationship is satisfied between the inner diameter d0m of the image side end surface of the lens barrel and the minimum aperture d3min of the third spacer element: 0.95 < d0m / d3min < 2.0. By restricting the relationship between the inner diameter of the image side end surface of the lens barrel and the minimum aperture of the third spacer element, the compatibility between the inner diameter of the image side end surface of the lens barrel and the minimum aperture of the third spacer element can be ensured, enabling the optical lens to be smoothly connected to other devices or components and maximizing the overall function. At the same time, effectively controlling the inner diameter of the image side end surface of the lens barrel and the minimum aperture of the third spacer element also helps to reduce problems such as stray light and ghost images in the system, contributing to improving the imaging quality of the optical lens.

[0066] In some alternative embodiments, the distance EP01 in the optical axis direction between the object-side end face of the lens barrel and the object-side face of the first spacer element, the distance SG11 in the optical axis direction from the intersection point of the object-side face of the first lens with the optical axis to the object-side face of the structural region of the first lens, and the central thickness CT1 of the first lens satisfy: 0.75 < EP01 / (SG11 + CT1) < 2.50. By restricting the relationship between the distance in the optical axis extension direction between the object-side end face of the lens barrel and the object-side face of the first spacer element, the axial distance from the intersection point of the object-side face of the first lens with the optical axis to the vertex of the effective radius of the object-side face of the first lens, and the central thickness of the first lens, the overall shape of the first lens can be constrained, facilitating the smooth entry of light into the optical system, providing sufficient optical performance for the optical lens while reducing the molding difficulty of the first lens and improving the yield of the first lens.

[0067] In some alternative embodiments, the distance SG11 in the optical axis direction from the intersection point of the object-side face of the first lens with the optical axis to the object-side face of the structural region of the first lens, the central thickness CT1 of the first lens, and the central thickness CT2 of the second lens satisfy: 1.65 < (SG11 + CT2) / CT1 < 3.30. By restricting the relationship between the axial distance from the intersection point of the object-side face of the first lens with the optical axis to the vertex of the effective radius of the object-side face of the first lens, the central thickness of the first lens, and the central thickness of the second lens, it helps to maintain the mechanical strength and stability of the first lens and the second lens, while optimizing their optical performance, and at the same time, the edge design of the lens can be further optimized to reduce problems such as stray light and ghost images.

[0068] In another embodiment, as Figures 1 to 18 shown, the optical lens includes a lens barrel and a lens group and a spacer element group assembled in the lens barrel. The lens group includes a first lens, a second lens, and a third lens in sequence along the optical axis from the object side to the image side. Among them, the second lens has a positive optical power; the spacer element group includes at least a first spacer element, a second spacer element, and a third spacer element. The first spacer element is located between the first lens and the second lens and is in partial contact with the image-side face of the first lens. The second spacer element is located between the second lens and the third lens and is in partial contact with the image-side face of the second lens. The third spacer element is located on the image side of the third lens, and the third spacer element is in partial contact with the image-side face of the third lens. The maximum height L of the lens barrel and the effective focal length f of the optical lens satisfy: 2.44 < L / f < 3.15; the distance Dr2r5 on the optical axis between the image-side face of the first lens and the object-side face of the third lens, the spacer distance EP12 in the optical axis direction between the first spacer element and the second spacer element, the central thickness CT3 of the third lens, and the spacer distance EP23 in the optical axis direction between the second spacer element and the third spacer element satisfy: 2.6 < Dr2r5 / EP12 + CT3 / EP23 < 3.45.

[0069] The optical lens of the present application is composed of a lens barrel, three lenses and at least two spacer elements. When 2.44 < L / f < 3.15 is satisfied between the maximum height L of the lens barrel and the effective focal length f of the optical lens, by restricting the relationship between the maximum height L of the lens barrel and the focal length of the optical lens, the space of the lens in the lens barrel can be constrained, which is conducive to restricting the thickness of the lens. While ensuring the overall size of the optical lens, the imaging quality of the optical lens can be guaranteed, enabling the optical lens to balance miniaturization and imaging quality. However, the development of the lens barrel towards miniaturization results in greater stress on the lens located in the middle and rear of the lens barrel, and the lens located in the middle and rear of the lens barrel is prone to breakage during the assembly process, resulting in poor assembly stability of the optical lens. The second lens and the third lens located in the middle and rear of the three lenses bear greater pressure, which is likely to cause the second lens or the third lens to break, and further lead to poor assembly stability of the optical lens. By restricting Dr2r5 / EP12 + CT3 / EP23 within a reasonable range, the overall shapes of the second lens and the third lens can be effectively restricted, which is conducive to the second lens and the third lens sharing stress evenly, reducing the risk of excessive stress at a local position of a certain lens, improving the stability of the structure of the second lens and the third lens, and further improving the assembly stability of the optical lens.

[0070] In another embodiment, as Figures 1 to 18 shown, the optical lens includes a lens barrel, a lens group and a spacer element group assembled in the lens barrel. The lens group sequentially includes a first lens, a second lens and a third lens along the optical axis from the object side to the image side. Among them, the second lens has a positive optical power, the image side surface of the first lens is concave, the image side surface of the second lens is convex, the object side surface of the third lens is convex, and the image side surface of the third lens is concave; the spacer element group includes at least a first spacer element and a second spacer element. The first spacer element is located between the first lens and the second lens and is in partial contact with the image side surface of the first lens. The second spacer element is located between the second lens and the third lens and is in partial contact with the image side surface of the second lens. The spacing distance EP12 between the first spacer element and the second spacer element in the optical axis direction and the central thickness CT2 of the second lens satisfy: 1.25 < CT2 / EP12 < 1.85; the radius of curvature R3 of the object side surface of the second lens, the radius of curvature R4 of the image side surface of the second lens, the inner diameter d1m of the image side surface of the first spacer element, and the inner diameter d2s of the object side surface of the second spacer element satisfy: 0.9 < (|R3| + |R4|) / (d2s + d1m) < 2.75.

[0071] The optical lens of the present application is composed of a lens barrel, three lenses and at least two spacer elements. When the distance EP12 between the first spacer element and the second spacer element in the optical axis direction and the central thickness CT2 of the second lens satisfy 1.25 < CT2 / EP12 < 1.85, by restricting the relationship between the central thickness and the edge thickness of the second lens, the structural strength of the second lens can be improved, which is beneficial to improving the assembly stability of the optical lens in a miniaturized space. Since the change of the second lens from the center to the edge is relatively fast, when light passes through the second lens, large-angle light that is prone to deflect towards the inner wall of the lens barrel is likely to be generated, resulting in the problem of stray light in the optical lens. In the present application, by restricting (|R3| + |R4|) / (d2s + d1m) within a reasonable range, the angle of the light entering the object side of the second lens can be restricted, reducing the deflection of the large-angle light entering the second lens to generate a larger angle, which is beneficial to reducing the generation of stray light. In addition, by restricting the curvature radii of the object side and the image side of the second lens, the light path of the light entering the second lens is adjusted, reducing the internal reflection stray light generated inside the second lens. The inner diameter of the image side of the first spacer element and the inner diameter of the object side of the second spacer element can cooperate to block the excess light entering the edge of the second lens and absorb the excess light generated after passing through the edge of the second lens, so that these non-imaging lights do not reach the imaging surface, further reducing the generation of stray light.

[0072] Of course, other parametric forms in the above embodiments may also be included in this embodiment, which will not be elaborated here one by one.

[0073] It should be noted that the above optical axis direction refers to the extension direction of the optical axis.

[0074] Optionally, the above optical lens may further include a protective glass for protecting the photosensitive element located on the imaging surface.

[0075] In the optical lens of the present application, multiple lenses can be used, such as the three lenses mentioned above. In the present application, at least one of the lens surfaces of each lens is an aspherical surface. The characteristics of an aspherical lens are that the curvature changes continuously from the center of the lens to the periphery of the lens. Different from a spherical lens with a constant curvature from the center of the lens to the periphery of the lens, an aspherical lens has better curvature radius characteristics and has the advantages of improving distortion aberration and astigmatism aberration. After using an aspherical lens, it is possible to eliminate the aberration that appears during imaging as much as possible, thereby improving the imaging quality.

[0076] However, those skilled in the art should understand that, without departing from the technical solution claimed in the present application, the number of lenses constituting the optical lens can be changed to obtain the various results and advantages described in this specification. For example, although three lenses are described as an example in the embodiments, the optical lens is not limited to including three lenses. If necessary, the optical lens may also include other numbers of lenses.

[0077] Figure 1 and Figure 2 Schematic diagrams of dimension marking of an optical lens of the present application are shown respectively, Figure 1 and Figure 2 Parameters such as d1s, D1m, d2s, d2m, D2m, d0m, EP01, EP12, EP23, L, Y, d3min, and SG11 are marked in the figure to clearly and intuitively understand the meaning of the parameters. In order to facilitate the description of the optical lens and the surface shape of the specific lens, these parameters will no longer be reflected in the drawings when the specific embodiments are described later.

[0078] The following further describes examples of specific surface shapes and parameters of the optical lens applicable to the above-mentioned embodiments with reference to the accompanying drawings.

[0079] It should be noted that in the following embodiment 1, there are two examples, namely, embodiment 1-1 and embodiment 1-2; in embodiment 2, there are two examples, namely, embodiment 2-1 and embodiment 2-2; in embodiment 3, there are two examples, namely, embodiment 3-1 and embodiment 3-2; and in embodiment 4, there are two examples, namely, embodiment 4-1 and embodiment 4-2. In the three examples of the same embodiment, the parameters such as the radius of curvature, center thickness, and the spacing distance between the lenses and the coefficients of the higher-order terms of the optical lenses of the first to third lenses are the same, but the parameters such as the thickness, inner diameter, and outer diameter of the lens barrel, the first spacing element, the second spacing element, and the third spacing element, as well as the shapes of some lenses are different. In other words, the main structures for imaging are the same, but the auxiliary structures for imaging are different.

[0080] It should be noted that any one of the following embodiments 1 to 4 is applicable to the present application.

[0081] Embodiment 1

[0082] like Figures 3 to 6 As shown, the optical lens of embodiment 1 is described. Figure 3 The structure diagram of the optical lens of Example 1-1 is shown. Figure 4 A schematic structural diagram of the optical lens of Example 1-2 is shown.

[0083] like Figure 3 and Figure 4As shown, the optical lens includes a lens barrel P0, three lenses and multiple spacer elements. The lens barrel P0 includes a first lens E1, a first spacer element P1, a second lens E2, a second spacer element P2, a third lens E3, and a third spacer element P3 arranged in sequence from the object side to the image side.

[0084] like Figure 3 As shown, it is a structural schematic diagram of the optical lens of embodiment 1-1. In this example, the object side surface S1 of the first lens abuts against the lens barrel P0 portion, the object side surface and the image side surface of the first spacing element P1 abut against the image side surface S2 of the first lens and the object side surface S3 of the second lens respectively, the object side surface and the image side surface of the second spacing element P2 abut against the image side surface S4 of the second lens and the object side surface S5 of the third lens respectively, and the image side surface S6 of the third lens abuts against the object side surface of the third spacing element P3. Wherein, the protruding structure 10 of the lens barrel is located in the middle part of the lens barrel.

[0085] like Figure 4 , which is a schematic diagram of the structure of the optical lens of Example 1-2. In Example 1-2, the abutting manner of each spacing element is similar to that of Example 1-1, and the relevant description in Example 1-1 may be referred to, and will not be repeated here.

[0086] In summary, the structural parameters of the optical lens of Example 1 in Example 1-1 and Example 1-2 are shown in Table 2. (Unit: mm)

[0087]

[0088]

[0089] Table 2

[0090] In the first embodiment, the first lens has positive focal power, the object side surface S1 of the first lens is convex, and the image side surface S2 of the first lens is concave. The second lens has positive focal power, the object side surface S3 of the second lens is concave, and the image side surface S4 of the second lens is convex. The third lens has negative focal power, the object side surface S5 of the third lens is convex, and the image side surface S6 of the third lens is concave. The aperture is located between the second lens and the third lens.

[0091] Table 3 shows the basic structural parameters of the optical lens of Example 1, wherein the units of the radius of curvature and thickness / distance are all millimeters.

[0092]

[0093] Table 3

[0094] In the first embodiment, the object side surface and the image side surface of the first lens E1 to the third lens E3 are all aspherical surfaces, and the surface shape of each aspherical lens can be defined by but not limited to the following aspherical surface formula:

[0095]

[0096] Among them, x is the distance vector height from the vertex of the aspherical surface when the aspherical surface is at a height of h along the optical axis; c is the paraxial curvature of the aspherical surface, c=1 / R, that is, the paraxial curvature c is the reciprocal of the curvature radius R in Table 1 above; k is the cone coefficient; Ai is the correction coefficient of the i-th order of the aspherical surface. The following Table 4 gives the high-order coefficients A4, A6, A8, A10, A12, A14, A16, A18, and A20 that can be used for each aspherical mirror surface S1-S6 in Example 1.

[0097] Face number A4 A6 A8 A10 A12 A14 A16 A18 A20 S1 4.83E+00 -4.64E+01 9.50E+02 -1.32E+04 1.21E+05 -6.69E+05 2.02E+06 -2.60E+06 0.00E+00 S2 2.13E+01 -5.48E+02 2.14E+04 -4.63E+05 4.98E+06 -3.12E+07 1.26E+08 0.00E+00 0.00E+00 S3 -2.27E+00 -2.62E+03 1.12E+05 -1.72E+06 1.28E+08 0.00E+00 0.00E+00 0.00E+00 0.00E+00 S4 2.75E+01 -7.95E+02 1.37E+04 -3.24E+05 3.73E+06 0.00E+00 0.00E+00 0.00E+00 0.00E+00 S5 -1.31E+01 9.46E+02 -5.53E+04 1.90E+06 -4.12E+07 5.70E+08 -4.83E+09 2.26E+10 -4.44E+10 S6 -8.63E+01 3.08E+03 -9.23E+04 1.91E+06 -2.65E+07 2.40E+08 -1.35E+09 4.30E+09 -5.93E+09

[0098] Table 4

[0099] Figure 5 The axial chromatic aberration curve of the optical lens of the first embodiment is shown, which indicates the deviation of the focusing point of light rays of different wavelengths after passing through the optical lens. Figure 6 The astigmatism curve of the optical lens of Example 1 is shown, which represents the meridional image curvature and the sagittal image curvature.

[0100] according to Figure 5 and Figure 6 It can be seen that the optical lens provided in the first embodiment can achieve good imaging quality.

[0101] Embodiment 2

[0102] like Figures 7 to 10 As shown, the optical lens of the second embodiment is described. Figure 7 The structure diagram of the optical lens of Example 2-1 is shown. Figure 8 A schematic structural diagram of the optical lens of Example 2-2 is shown.

[0103] like Figure 7 and Figure 8 As shown, the optical lens includes a lens barrel P0, three lenses and multiple spacer elements. The lens barrel P0 includes a first lens E1, a first spacer element P1, a second lens E2, a second spacer element P2, a third lens E3, and a third spacer element P3 arranged in sequence from the object side to the image side.

[0104] like Figure 7As shown, it is a structural schematic diagram of the optical lens of embodiment 2-1. In this example, the object side surface S1 of the first lens abuts against the lens barrel P0 portion, the object side surface and the image side surface of the first spacing element P1 abut against the image side surface S2 of the first lens and the object side surface S3 of the second lens respectively, the object side surface and the image side surface of the second spacing element P2 abut against the image side surface S4 of the second lens and the object side surface S5 of the third lens respectively, and the image side surface S6 of the third lens abuts against the object side surface of the third spacing element P3. Wherein, the protruding structure 10 of the lens barrel is located at one end of the lens barrel close to the image side.

[0105] like Figure 8 , which is a schematic diagram of the structure of the optical lens of Example 2-2. In Example 2-2, the supporting and abutting manner of each spacing element is similar to that of Example 2-1, and the relevant description in Example 2-1 may be referred to, and will not be repeated here.

[0106] In summary, the structural parameters of the optical lens of Example 2 in Example 2-1 and Example 2-2 are shown in Table 5. (Unit: mm)

[0107]

[0108]

[0109] Table 5

[0110] In the second embodiment, the first lens has negative power, the object side surface S1 of the first lens is convex, and the image side surface S2 of the first lens is concave. The second lens has positive power, the object side surface S3 of the second lens is convex, and the image side surface S4 of the second lens is convex. The third lens has positive power, the object side surface S5 of the third lens is convex, and the image side surface S6 of the third lens is concave. The aperture is located between the second lens and the third lens.

[0111] Table 6 shows the basic structural parameters of the optical lens of Example 2, wherein the units of the radius of curvature and thickness / distance are all millimeters.

[0112]

[0113] Table 6

[0114] Table 7 shows the high-order coefficients of each aspherical mirror surface that can be used in Example 2, wherein each aspherical surface shape can be defined by formula (1) given in the above Example 1. In this embodiment, the object side surface and image side surface of the first lens to the third lens are all aspherical surfaces.

[0115] Face number A4 A6 A8 A10 A12 A14 A16 A18 A20 S1 4.03E+00 -5.28E+01 1.20E+03 -1.53E+04 1.12E+05 -3.60E+05 0.00E+00 0.00E+00 0.00E+00 S2 0.00E+00 0.00E+00 0.00E+00 0.00E+00 0.00E+00 0.00E+00 0.00E+00 0.00E+00 0.00E+00 S3 1.00E+02 -6.26E+04 1.69E+07 -2.40E+09 1.70E+11 -4.68E+12 0.00E+00 0.00E+00 0.00E+00 S4 -1.12E+02 9.38E+03 -5.00E+05 1.57E+07 -2.61E+08 1.76E+09 0.00E+00 0.00E+00 0.00E+00 S5 -2.69E+01 -8.27E+01 5.70E+04 -3.07E+06 8.50E+07 -1.32E+09 1.08E+10 -3.59E+10 0.00E+00 S6 -7.38E+01 1.88E+03 -4.69E+04 8.53E+05 -1.06E+07 8.38E+07 -3.76E+08 7.25E+08 0.00E+00

[0116] Table 7

[0117] Fig. 9The axial chromatic aberration curve of the optical lens of the second embodiment is shown, which indicates the deviation of the focusing point of light rays of different wavelengths after passing through the optical lens. Fig.10 The astigmatism curve of the optical lens of Example 2 is shown, which represents the meridional image curvature and the sagittal image curvature.

[0118] according to Fig. 9 and Fig.10 It can be seen that the optical lens provided in the second embodiment can achieve good imaging quality.

[0119] Embodiment 3

[0120] like Figures 11 to 14 As shown, the optical lens of embodiment 3 is described. Fig.11 The structure diagram of the optical lens of Example 3-1 is shown. Fig.12 A schematic structural diagram of the optical lens of Example 3-2 is shown.

[0121] like Fig.11 and Fig.12 As shown, the optical lens includes a lens barrel P0, three lenses and multiple spacer elements. The lens barrel P0 includes a first lens E1, a first spacer element P1, a second lens E2, a second spacer element P2, a third lens E3, and a third spacer element P3 arranged in sequence from the object side to the image side.

[0122] like Fig.11 As shown, it is a structural schematic diagram of the optical lens of Example 3-1. In this example, the object side surface S1 of the first lens abuts against the lens barrel P0 portion, the object side surface and the image side surface of the first spacing element P1 abut against the image side surface S2 of the first lens and the object side surface S3 of the second lens respectively, the object side surface and the image side surface of the second spacing element P2 abut against the image side surface S4 of the second lens and the object side surface S5 of the third lens respectively, and the image side surface S6 of the third lens abuts against the object side surface of the third spacing element P3. Wherein, the protruding structure 10 of the lens barrel is located at one end of the lens barrel close to the image side.

[0123] like Fig.12 , which is a schematic diagram of the structure of the optical lens of Example 3-2. In Example 3-2, the supporting and abutting manner of each spacing element is similar to that of Example 3-1, and the relevant description in Example 3-1 may be referred to, and will not be repeated here.

[0124] In summary, the structural parameters of the optical lens of Example 3 in Example 3-1 and Example 3-2 are shown in Table 8. (Unit: mm)

[0125]

[0126]

[0127] Table 8

[0128] In the third embodiment, the first lens has negative power, the object side surface S1 of the first lens is convex, and the image side surface S2 of the first lens is concave. The second lens has positive power, the object side surface S3 of the second lens is convex, and the image side surface S4 of the second lens is convex. The third lens has positive power, the object side surface S5 of the third lens is convex, and the image side surface S6 of the third lens is concave. The aperture is located between the second lens and the third lens.

[0129] Table 9 shows the basic structural parameters of the optical lens of Example 3, wherein the units of the radius of curvature and thickness / distance are all millimeters.

[0130]

[0131] Table 9

[0132] Table 10 shows the coefficients of the higher order terms that can be used for each aspherical mirror surface in Example 3, wherein each aspherical surface type can be defined by the formula (1) given in the above Example 1. In this embodiment, the object side surface and the image side surface of the first lens to the third lens are all aspherical surfaces.

[0133] Face number A4 A6 A8 A10 A12 A14 A16 A18 A20 S1 3.10E+00 1.21E+01 9.49E+02 -5.24E+03 -1.58E+05 3.48E+06 0.00E+00 0.00E+00 0.00E+00 S2 3.46E+00 3.10E+03 -3.66E+05 2.66E+07 -9.24E+08 1.53E+10 0.00E+00 0.00E+00 0.00E+00 S3 -2.57E+00 6.60E+01 -5.13E+05 6.63E+07 -3.27E+09 4.96E+10 0.00E+00 0.00E+00 0.00E+00 S4 -6.01E+01 4.34E+03 -2.05E+05 6.28E+06 -1.06E+08 7.62E+08 0.00E+00 0.00E+00 0.00E+00 S5 -7.58E+01 3.72E+03 -1.74E+05 5.46E+06 -1.09E+08 1.28E+09 -8.01E+09 2.15E+10 0.00E+00 S6 -6.20E+01 1.59E+03 -3.76E+04 6.12E+05 -6.70E+06 4.56E+07 -1.77E+08 3.19E+08 0.00E+00

[0134] Table 10

[0135] Fig.13 The axial chromatic aberration curve of the optical lens of the third embodiment is shown, which indicates the deviation of the focusing point of light rays of different wavelengths after passing through the optical lens. Fig.14 The astigmatism curve of the optical lens of Example 3 is shown, which represents the meridional image curvature and the sagittal image curvature.

[0136] according to Fig.13 and Fig.14 It can be seen that the optical lens provided in the third embodiment can achieve good imaging quality.

[0137] Embodiment 4

[0138] like Figures 15 to 18 As shown, the optical lens of embodiment 4 is described. Fig.15 The structure diagram of the optical lens of Example 3-1 is shown. Fig.16 A schematic structural diagram of the optical lens of Example 3-2 is shown.

[0139] like Fig.15 and Fig.16 As shown, the optical lens includes a lens barrel P0, three lenses and multiple spacer elements. The lens barrel P0 includes a first lens E1, a first spacer element P1, a second lens E2, a second spacer element P2, a third lens E3, and a third spacer element P3 arranged in sequence from the object side to the image side.

[0140] like Fig.15 As shown, it is a structural schematic diagram of the optical lens of Example 3-1. In this example, the object side surface S1 of the first lens abuts against the lens barrel P0 portion, the object side surface and the image side surface of the first spacing element P1 abut against the image side surface S2 of the first lens and the object side surface S3 of the second lens respectively, the object side surface and the image side surface of the second spacing element P2 abut against the image side surface S4 of the second lens and the object side surface S5 of the third lens respectively, and the image side surface S6 of the third lens abuts against the object side surface of the third spacing element P3. Wherein, the protruding structure 10 of the lens barrel is located at one end of the lens barrel close to the image side.

[0141] like Fig.16 , which is a schematic diagram of the structure of the optical lens of Example 3-2. In Example 3-2, the supporting and abutting manner of each spacing element is similar to that of Example 3-1, and the relevant description in Example 3-1 may be referred to, and will not be repeated here.

[0142] In summary, the structural parameters of the optical lens of Example 4 under Example 3-1 and Example 3-2 are shown in Table 11. (Unit: mm)

[0143] Parameters / Examples 2-1 2-2 d1s 0.268 0.249 d1m 0.268 0.249 D1m 1.300 0.875 d2s 0.481 0.512 d2m 0.481 0.512 D2m 1.430 1.452 d0m 1.810 1.860 EP01 0.422 0.435 EP12 0.190 0.229 EP23 0.209 0.249 L 1.279 1.260 Y 3.167 3.216 SG11 0.010 0.024 d3min 1.105 1.133

[0144] Table 11

[0145] In Embodiment 4, the first lens has negative power, the object side surface S1 of the first lens is concave, and the image side surface S2 of the first lens is concave. The second lens has positive power, the object side surface S3 of the second lens is convex, and the image side surface S4 of the second lens is convex. The third lens has negative power, the object side surface S5 of the third lens is convex, and the image side surface S6 of the third lens is concave. The aperture is located between the second lens and the third lens.

[0146] Table 12 shows the basic structural parameters of the optical lens of Example 4, wherein the units of the radius of curvature and thickness / distance are all millimeters (mm).

[0147] Face number Face type Radius of curvature thickness Material Cone coefficient OBJ Spherical endless 100.0000 Refractive Index Abbe number S1 Aspheric -2.4507 0.1609 1.546 55.99 0.0000 S2 Aspheric 0.6035 0.1151 STO Spherical endless 0.0175 0.0000 S3 Aspheric 0.5269 0.3481 1.546 55.99 -46.5114 S4 Aspheric -0.1692 0.0216 -0.5662 S5 Aspheric 1.0790 0.1426 1.678 19.24 13.6873 S6 Aspheric 0.2293 0.1473 -2.4059 S7 Spherical endless 0.1100 1.542 47 S8 Spherical endless 0.0750 S9 Spherical endless

[0148] Table 12

[0149] Table 13 shows the high-order coefficients of each aspherical mirror surface that can be used in Example 4, wherein each aspherical surface type can be defined by the formula (1) given in the above Example 1. In this embodiment, the object side surface and the image side surface of the first lens to the third lens are all aspherical surfaces.

[0150] Face number A4 A6 A8 A10 A12 A14 A16 A18 A20 S1 7.04E+00 -6.03E+01 -4.03E+02 1.44E+04 -1.46E+05 5.75E+05 0.00E+00 0.00E+00 0.00E+00 S2 -7.73E+00 6.46E+03 -7.26E+05 4.07E+07 -1.15E+09 1.28E+10 0.00E+00 0.00E+00 0.00E+00 S3 2.35E+01 -1.31E+03 -7.18E+04 7.71E+06 -2.05E+08 1.59E+09 -1.43E+09 0.00E+00 0.00E+00 S4 1.19E+01 5.24E+02 -1.33E+04 -6.44E+05 4.25E+07 -8.52E+08 6.03E+09 0.00E+00 0.00E+00 S5 -4.96E+01 2.86E+03 -1.61E+05 5.61E+06 -1.19E+08 1.43E+09 -8.50E+09 1.74E+10 0.00E+00 S6 -5.45E+01 2.18E+03 -6.89E+04 1.46E+06 -2.00E+07 1.67E+08 -7.64E+08 1.46E+09 0.00E+00

[0151] Table 13

[0152] Fig.17 The axial chromatic aberration curve of the optical lens of Example 4 is shown, which indicates the deviation of the focusing point of light rays of different wavelengths after passing through the optical lens. Fig.18 The astigmatism curve of the optical lens of Example 4 is shown, which represents the meridional image curvature and the sagittal image curvature.

[0153] according to Fig.17 and Fig.18 It can be seen that the optical lens provided in the fourth embodiment can achieve good imaging quality.

[0154] In summary, the optical lenses of Examples 1 to 4 respectively satisfy the relationships shown in Table 14.

[0155]

[0156]

[0157] Table 14

[0158] Table 15 shows the effective focal length and half field angle (unit: mm) of each lens of the optical lens of Examples 1 to 4.

[0159] Parameters / Examples one two three Four Semi-FOV 49.46 51.38 40.74 57.45 f 0.43 0.44 0.44 0.41 f1 83.95 -1.12 -0.84 -0.87 f2 0.27 0.39 0.43 0.28 f3 -0.42 10930.20 1.79 -0.45

[0160] Table 15

[0161] Obviously, the above-described embodiments are only a part of the embodiments of the present invention, rather than all the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by ordinary technicians in this field without creative work should fall within the scope of protection of the present invention.

[0162] It should be noted that the terms used herein are only for describing specific embodiments and are not intended to limit the exemplary embodiments according to the present application. As used herein, unless the context clearly indicates otherwise, the singular form is also intended to include the plural form. In addition, it should be understood that when the terms "comprise" and / or "include" are used in this specification, it indicates the presence of features, steps, operations, devices, components and / or combinations thereof.

[0163] It should be noted that the terms "first", "second", etc. in the specification and claims of the present application and the above-mentioned drawings are used to distinguish similar objects, and are not necessarily used to describe a specific order or sequence. It should be understood that the numbers used in this way can be interchanged where appropriate, so that the embodiments of the present application described herein can be implemented in an order other than those illustrated or described herein.

[0164] The above description is only a preferred embodiment of the present invention and is not intended to limit the present invention. For those skilled in the art, the present invention may have various modifications and variations. Any modification, equivalent replacement, improvement, etc. made within the spirit and principle of the present invention shall be included in the protection scope of the present invention.

Claims

1. An optical lens, characterized in that: The invention comprises a lens barrel and a lens group and a spacer element group assembled in the lens barrel. The lens group includes a first lens, a second lens and a third lens in sequence from the object side to the image side along the optical axis, wherein the second lens has positive optical power, a center thickness of the second lens is greater than a center thickness of the first lens, and a center thickness of the second lens is greater than a center thickness of the third lens; The spacer element group includes at least a first spacer element and a second spacer element, the first spacer element is located between the first lens and the second lens and at least partially contacts the image side surface of the first lens, and the second spacer element is located between the second lens and the third lens and at least partially contacts the image side surface of the second lens; The maximum height L of the lens barrel and the effective focal length f of the optical lens satisfy the following conditions: 2.44 <L / f<3.15; The effective focal length f2 of the second lens, the spacing distance EP12 between the first spacing element and the second spacing element in the optical axis direction, and the center thickness CT2 of the second lens satisfy: 2.90 mm -1 <(CT2 / EP12) / f2<6.56mm -1 .

2. The optical lens according to claim 1, characterized in that: The outer peripheral surface of the lens barrel has a protruding structure, and the maximum outer diameter Y of the protruding structure satisfies: 3.1 mm <Y<3.4mm。 3. The optical lens according to claim 1, characterized in that: The spacing distance EP12 between the first spacing element and the second spacing element in the optical axis direction, the center thickness CT2 of the second lens, and the inner diameter d2m of the image side surface of the second spacing element satisfy: 1.05 mm -1 <EP12 / CT2 / d2m<1.75mm -1 .

4. The optical lens according to claim 1, characterized in that: The curvature radius R2 of the image side surface of the first lens, the curvature radius R3 of the object side surface of the second lens, and the inner diameter d2s of the object side surface of the second spacer element satisfy the following relationship: 1.25<(R2+R3) / d2s<4.

20.

5. The optical lens according to claim 1, characterized in that: An inner diameter d2m of the image-side surface of the second spacer element, an outer diameter D2m of the image-side surface of the second spacer element, and an inner diameter d1s of the object-side surface of the first spacer element satisfy the following: 2.0<(D2m-d1s) / d2m<3.

45.

6. The optical lens according to claim 1, characterized in that: The spacer element group further includes a third spacer element, the third spacer element is located on the image side of the third lens, and the third spacer element is in at least partial contact with the image side surface of the third lens, The center thickness CT2 of the second lens, the center thickness CT3 of the third lens, and the center thickness CT1 of the first lens satisfy: 0.70 <CT2 / (CT3+CT1)<1.45; The spacing distance EP12 between the first spacing element and the second spacing element in the optical axis direction, the distance EP01 between the object side end surface of the lens barrel and the object side surface of the first spacing element in the optical axis direction, and the spacing distance EP23 between the second spacing element and the third spacing element in the optical axis direction satisfy: 0.25 <EP12 / (EP01+EP23)<0.5。 7. The optical lens according to claim 1, characterized in that: The inner diameter d2s of the object side surface of the second spacing element, the outer diameter D2m of the image side surface of the second spacing element, the outer diameter D1m of the image side surface of the first spacing element, and the inner diameter d1s of the object side surface of the first spacing element satisfy: 2.10 <D2m / D1m+d2s / d1s<3.80。 8. The optical lens according to claim 1, characterized in that: The effective focal length f of the optical lens, half of the maximum field of view Semi-FOV of the optical lens and the maximum height L of the lens barrel satisfy the following conditions: 0.25 <f*tan(Semi-FOV) / L<0.55。 9. The optical lens according to claim 1, characterized in that: The spacer element group further includes a third spacer element, the third spacer element is located on the image side of the third lens, and the third spacer element is in contact with the image side surface portion of the third lens, and the spacing distance EP23 between the second spacer element and the third spacer element in the optical axis direction, the outer diameter D2m of the image side surface of the second spacer element, and the inner diameter d2m of the image side surface of the second spacer element satisfy: 0.10 <EP23 / (D2m-d2m)<0.28。 10. The optical lens according to claim 1, characterized in that: The spacer element group further includes a third spacer element, the third spacer element is located on the image side of the third lens, and the third spacer element is in contact with the image side surface of the third lens, and the inner diameter d0m of the image side end surface of the lens barrel and the minimum aperture d3min of the third spacer element satisfy the following relationship: 0.95 <d0m / d3min<2.0。 11. The optical lens according to any one of claims 1 to 10, characterized in that: The distance EP01 between the object side end face of the lens barrel and the object side face of the first spacer element in the direction of the optical axis, the distance SG11 from the intersection of the object side face of the first lens and the optical axis to the object side face of the structure region of the first lens in the direction of the optical axis, and the center thickness CT1 of the first lens satisfy the following conditions: 0.75 <EP01 / (SG11+CT1)<2.50。 12. The optical lens according to any one of claims 1 to 10, characterized in that: The distance SG11 from the intersection of the object side surface of the first lens and the optical axis to the object side surface of the structural area of ​​the first lens along the optical axis direction, the center thickness CT1 of the first lens, and the center thickness CT2 of the second lens satisfy the following: 1.65<(SG11+CT2) / CT1<3.

30.

13. The optical lens according to any one of claims 1 to 10, characterized in that: The optical lens meets at least one of the following requirements: The image side surface of the first lens is a concave surface; The image side surface of the second lens is a convex surface; The object side surface of the third lens is a convex surface, and the image side surface of the third lens is a concave surface; The image-side surface of the third lens has an inflection point.

Images