Optical imaging lens

Abstract

The present application discloses an optical imaging lens, which sequentially includes, from the object side to the image side along the optical axis: a first lens with refractive power; a second lens with negative refractive power; a third lens with negative refractive power; a fourth lens with refractive power; a fifth lens with negative refractive power; a sixth lens with negative refractive power, whose image side is convex; a seventh lens with refractive power; and an eighth lens with refractive power, whose object side is convex; the number of lenses with refractive power in the optical imaging lens is eight, wherein, the effective focal length f8 of the eighth lens and the curvature radius R15 of the object side of the eighth lens satisfy: f8 / R15 < 0, the effective focal length f6 of the sixth lens and the curvature radius R12 of the image side of the sixth lens satisfy: 0 < R12 / f6 < 6, and the central thickness CT4 of the fourth lens on the optical axis and the air interval T12 between the first lens and the second lens on the optical axis satisfy: 0 < CT4 / T12 < 10.

Description

Technical Field

[0001] This application relates to the field of optical devices, and particularly to an eight-element optical imaging lens. Background Art

[0002] With the rapid development of portable devices such as smart phones, more new requirements are put forward for the imaging functions of portable devices such as smart phones. For example, through the optical design of the optical imaging lens, the optical imaging lens of portable devices such as smart phones can meet the requirements of high imaging quality while achieving ultra-thinness. However, in the actual design process, traditional eight-element optical imaging lenses cannot achieve both ultra-thinness and high imaging quality at the same time. Summary of the Invention

[0003] This application provides an optical imaging lens that can at least solve or partially solve at least one problem or other problems existing in the prior art.

[0004] One aspect of this application provides such an optical imaging lens, which sequentially includes, along the optical axis from the object side to the image side: a first lens with refractive power; a second lens with negative refractive power; a third lens with negative refractive power; a fourth lens with refractive power; a fifth lens with negative refractive power; a sixth lens with negative refractive power, whose image side is convex; a seventh lens with refractive power; and an eighth lens with refractive power, whose object side is convex; the number of lenses with refractive power in the optical imaging lens is eight, wherein, the effective focal length f8 of the eighth lens and the curvature radius R15 of the object side of the eighth lens satisfy: f8 / R15 < 0, the effective focal length f6 of the sixth lens and the curvature radius R12 of the image side of the sixth lens satisfy: 0 < R12 / f6 < 6, and the central thickness CT4 of the fourth lens on the optical axis and the air interval T12 of the first lens and the second lens on the optical axis satisfy: 0 < CT4 / T12 < 10.

[0005] According to an exemplary embodiment of this application, the on-axis distance TTL from the object side of the first lens to the imaging surface of the optical imaging lens and half of the diagonal length ImgH of the effective pixel region on the imaging surface of the optical imaging lens satisfy: TTL / ImgH < 1.4.

[0006] According to an exemplary embodiment of this application, half of the maximum field of view Semi-FOV of the optical imaging lens and half of the diagonal length ImgH of the effective pixel region on the imaging surface of the optical imaging lens satisfy: 6.5mm < tan(Semi-FOV) × ImgH < 10mm.

[0007] According to an exemplary embodiment of the present application, the edge thickness ET8 at the maximum effective aperture of the eighth lens and the central thickness CT8 of the eighth lens on the optical axis satisfy: 1.03 ≤ ET8 / CT8 < 7.

[0008] According to an exemplary embodiment of the present application, the central thickness CT2 of the second lens on the optical axis, the central thickness CT3 of the third lens on the optical axis, the central thickness CT6 of the sixth lens on the optical axis, and the central thickness CT7 of the seventh lens on the optical axis satisfy: 1 < (CT2 + CT7) / (CT3 + CT6) < 3.

[0009] According to an exemplary embodiment of the present application, the edge thickness ET5 at the maximum effective aperture of the fifth lens and the central thickness CT5 of the fifth lens on the optical axis satisfy: 0.1 < ET5 / CT5 < 1.

[0010] According to an exemplary embodiment of the present application, the effective focal length f2 of the second lens, 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: -15 < f2 / (R3 - R4) < 0.

[0011] According to an exemplary embodiment of the present application, 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: -6 < (R11 + R12) / (R11 - R12) < -1.

[0012] According to an exemplary embodiment of the present application, the central thickness CT5 of the fifth lens on the optical axis, the central thickness CT6 of the sixth lens on the optical axis, and the air gap T56 between the fifth lens and the sixth lens on the optical axis satisfy: 0.4 < (CT5 + CT6) / T56 < 2.

[0013] According to an exemplary embodiment of the present application, the effective focal length f6 of the sixth lens, the effective focal length f7 of the seventh lens, the curvature radius R11 of the object side of the sixth lens, and the curvature radius R13 of the object side of the seventh lens satisfy: 3 < f6 / R11 + f7 / R13 < 9.

[0014] According to an exemplary embodiment of the present application, the effective semi-aperture DT72 of the image side of the seventh lens, the effective semi-aperture DT81 of the object side of the eighth lens, and the effective semi-aperture DT82 of the image side of the eighth lens satisfy: 1 < DT81 / (DT82 - DT72) < 4.5.

[0015] According to an exemplary embodiment of the present application, the minimum value Nmin of the refractive indices of all the lenses from the first lens to the eighth lens satisfies: Nmin > 1.5, and the minimum value Vmin of the Abbe numbers of all the lenses from the first lens to the eighth lens satisfies: Vmin < 20.

[0016] According to an exemplary embodiment of the present application, the on-axis distance BFL from the image side of the eighth lens to the imaging surface of the optical imaging lens and the sum ∑CT of the central thicknesses of all the lenses from the first lens to the eighth lens on the optical axis satisfy: 1 < ∑CT / BFL < 4.

[0017] According to an exemplary embodiment of the present application, the object sides of the first lens to the third lens are all convex surfaces, and the image sides of the first lens to the third lens are all concave surfaces.

[0018] According to an exemplary embodiment of the present application, the number of lenses with negative refractive power among the first lens to the eighth lens is greater than the number of lenses with positive refractive power among the first lens to the eighth lens.

[0019] By controlling the relationship between the focal length and the radius of curvature of the lenses in the optical imaging lens, the present application is conducive to ensuring that the lenses have appropriate refractive power, thereby effectively balancing the aberration of the optical imaging lens and improving the imaging quality of the optical imaging lens; at the same time, the sizes of the lenses in the optical imaging lens can be reasonably arranged to ensure that the optical imaging lens is thinned. BRIEF DESCRIPTION OF THE DRAWINGS

[0020] Other features, objects, and advantages of the present application will become more apparent by reading the following detailed description of non-limiting embodiments with reference to the accompanying drawings:

[0021] Figure 1 Shows a schematic structural diagram of an optical imaging lens according to Embodiment 1 of the present application;

[0022] Figures 2A to 2D Respectively show the axial chromatic aberration curve, astigmatism curve, distortion curve, and lateral chromatic aberration curve of the optical imaging lens according to Embodiment 1 of the present application;

[0023] Figure 3 Shows a schematic structural diagram of an optical imaging lens according to Embodiment 2 of the present application;

[0024] Figures 4A to 4D Respectively show the axial chromatic aberration curve, astigmatism curve, distortion curve, and lateral chromatic aberration curve of the optical imaging lens according to Embodiment 2 of the present application;

[0025] Figure 5 Shows a schematic structural diagram of an optical imaging lens according to Embodiment 3 of the present application;

[0026] Figures 6A to 6D Respectively show the axial chromatic aberration curve, astigmatism curve, distortion curve, and lateral chromatic aberration curve of the optical imaging lens according to Embodiment 3 of the present application;

[0027] Figure 7Shows a schematic structural diagram of an optical imaging lens according to Embodiment 4 of the present application;

[0028] Figures 8A to 8D Respectively show the axial chromatic aberration curve, astigmatism curve, distortion curve, and lateral chromatic aberration curve of the optical imaging lens according to Embodiment 4 of the present application;

[0029] Figure 9 Shows a schematic structural diagram of an optical imaging lens according to Embodiment 5 of the present application;

[0030] Figures 10A to 10D Respectively show the axial chromatic aberration curve, astigmatism curve, distortion curve, and lateral chromatic aberration curve of the optical imaging lens according to Embodiment 5 of the present application;

[0031] Figure 11 Shows a schematic structural diagram of an optical imaging lens according to Embodiment 6 of the present application; and

[0032] Figures 12A to 12D Respectively show the axial chromatic aberration curve, astigmatism curve, distortion curve, and lateral chromatic aberration curve of the optical imaging lens according to Embodiment 6 of the present application. Detailed implementation manners

[0033] To better understand the present application, more detailed descriptions of various aspects of the present application will be made with reference to the accompanying drawings. It should be understood that these detailed descriptions are only descriptions of the exemplary embodiments of the present application and do not limit the scope of the present application in any way. Throughout the specification, the same reference numerals refer to the same elements.

[0034] It should be noted that in this specification, the expressions such as first, second, and third are only used to distinguish one feature from another feature and do not represent any limitation on the feature. Therefore, without departing from the teachings of the present application, the first lens discussed below may also be referred to as the second lens or the third lens.

[0035] In the drawings, for the sake of convenience of illustration, the thickness, size, and shape of the lens have been slightly exaggerated. Specifically, the spherical or aspherical shapes shown in the drawings are shown by way of example. That is, the spherical or aspherical shapes are not limited to the spherical or aspherical shapes shown in the drawings. The drawings are only examples and are not drawn strictly to scale.

[0036] In this article, the paraxial region refers to the region near the optical axis. If the lens surface is convex and the position of the convex surface is not defined, it means that the lens surface is convex at least in the paraxial region; if the lens surface is concave and the position of the concave surface is not defined, it means that the lens surface is concave at least in the paraxial region. The surface of each lens closest to the object to be photographed is called the object side surface of the lens, and the surface of each lens closest to the imaging surface is called the image side surface of the lens.

[0037] It should also be understood that the terms "comprise", "comprising", "have", "including" and / or "including having", when used in this specification, denote the presence of the stated features, elements and / or components, but do not preclude the presence or addition of one or more other features, elements, components and / or combinations thereof. In addition, when describing the embodiments of the present application, the use of "may" means "one or more embodiments of the present application". Also, the term "exemplary" is intended to refer to an example or illustration.

[0038] Unless otherwise defined, all terms (including technical and scientific terms) used herein have the same meaning as commonly understood by one of ordinary skill in the art to which this application belongs. It should also be understood that terms (such as those defined in a common dictionary) should be interpreted as having a meaning consistent with their meaning in the context of the relevant art and will not be interpreted in an idealized or overly formal sense unless expressly so defined herein.

[0039] It should be noted that, without conflict, the embodiments in the present application and the features in the embodiments may be combined with each other. The present application will be described in detail below with reference to the drawings and in conjunction with the embodiments.

[0040] The features, principles and other aspects of the present application will be described in detail below.

[0041] An optical imaging lens according to an exemplary embodiment of the present application may include a first lens having a refractive power, a second lens having a negative refractive power, a third lens having a negative refractive power, a fourth lens having a refractive power, a fifth lens having a negative refractive power, a sixth lens having a negative refractive power, a seventh lens having a refractive power, and an eighth lens having a refractive power. These eight lenses are arranged in order from the object side to the image side along the optical axis. An air gap may be provided between any two adjacent lenses among the first lens to the eighth lens. The image side surface of the sixth lens is convex, and the object side surface of the eighth lens is convex.

[0042] Among them, the effective focal length f8 of the eighth lens and the curvature radius R15 of the object side surface of the eighth lens may satisfy: f8 / R15 < 0; the effective focal length f6 of the sixth lens and the curvature radius R12 of the image side surface of the sixth lens may satisfy: 0 < R12 / f6 < 6; and the central thickness CT4 of the fourth lens on the optical axis and the air gap T12 between the first lens and the second lens on the optical axis may satisfy: 0 < CT4 / T12 < 10. In the example, -5 < f8 / R15 < 0, 0 < R12 / f6 < 1, 3.5 < CT4 / T12 < 8.5. By controlling the relationship between the focal length and the curvature radius of the lenses in the optical imaging lens, it is beneficial to ensure that the lenses have appropriate refractive power, thereby effectively balancing the aberration of the optical imaging lens and improving the imaging quality of the optical imaging lens; at the same time, the sizes of the lenses in the optical imaging lens can be reasonably arranged to ensure that the optical imaging lens is ultra-thin.

[0043] In an exemplary embodiment, the object side surfaces of the first lens to the third lens are all convex surfaces, and the image side surfaces of the first lens to the third lens are all concave surfaces. Reasonably controlling the surface types of the object side surfaces and the image side surfaces of the first lens to the third lens is beneficial for the optical imaging lens to better adjust the light focusing position, improve the light converging ability of the optical imaging lens, and effectively balance the on-axis aberration of the optical imaging lens.

[0044] In an exemplary embodiment, the number of lenses with negative refractive power among the first lens to the eighth lens is greater than the number of lenses with positive refractive power among the first lens to the eighth lens. Reasonably controlling the number of positive lenses and negative lenses in the optical imaging lens is beneficial for balancing the aberration of the optical imaging lens and improving the resolution of the optical imaging lens.

[0045] In an exemplary embodiment, the on-axis distance TTL from the object side surface of the first lens to the imaging surface of the optical imaging lens and half of the diagonal length ImgH of the effective pixel region on the imaging surface of the optical imaging lens may satisfy: TTL / ImgH < 1.4. In the example, 0.95 < TTL / ImgH < 1.25. By constraining the ratio of the on-axis distance from the object side surface of the first lens to the optical imaging lens to half of the diagonal length of the effective pixel region on the imaging surface of the optical imaging lens within a reasonable range, it is beneficial for the optical imaging lens to achieve a shorter optical total length while achieving a larger imaging height, ensuring that the optical imaging lens takes into account miniaturization and high imaging quality at the same time.

[0046] In an exemplary embodiment, half of the maximum field of view (Semi-FOV) of the optical imaging lens and half of the diagonal length (ImgH) of the effective pixel region on the imaging surface of the optical imaging lens satisfy: 6.5 mm < tan(Semi-FOV) × ImgH < 10 mm. Reasonably controlling the relationship between half of the maximum field of view of the optical imaging lens and half of the diagonal length of the effective pixel region on the imaging surface of the optical imaging lens is beneficial for the optical imaging lens to meet the requirement of a large field of view while achieving ultra-thinness.

[0047] In an exemplary embodiment, the edge thickness (ET8) at the maximum effective aperture of the eighth lens and the central thickness (CT8) of the eighth lens on the optical axis can satisfy: 1.03 ≤ ET8 / CT8 < 7. In an example, 1.03 ≤ ET8 / CT8 < 3.5. By restricting the ratio of the edge thickness to the central thickness of the eighth lens within a certain range, it is beneficial to control the decentration ratio of the eighth lens to ensure the processability of the eighth lens while ensuring its performance.

[0048] In an exemplary embodiment, the central thickness (CT2) of the second lens on the optical axis, the central thickness (CT3) of the third lens on the optical axis, the central thickness (CT6) of the sixth lens on the optical axis, and the central thickness (CT7) of the seventh lens on the optical axis can satisfy: 1 < (CT2 + CT7) / (CT3 + CT6) < 3. By restricting the central thicknesses of the second lens, the third lens, the sixth lens, and the seventh lens on the optical axis, the size of the optical imaging lens can be effectively reduced, avoiding the optical imaging lens from being too large in volume. At the same time, the optical imaging lens can have a high space utilization rate and the assembly difficulty of the lenses can be reduced.

[0049] In an exemplary embodiment, the edge thickness (ET5) at the maximum effective aperture of the fifth lens and the central thickness (CT5) of the fifth lens on the optical axis can satisfy: 0.1 < ET5 / CT5 < 1. By restricting the ratio of the edge thickness to the central thickness of the fifth lens within a certain range, it is beneficial to reduce the processing and assembly difficulty of the fifth lens to ensure the processability of the fifth lens while ensuring its performance.

[0050] In an exemplary embodiment, the effective focal length (f2) of the second lens, 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 can satisfy: -15 < f2 / (R3 - R4) < 0. In an example, -11.5 < f2 / (R3 - R4) < -4.0. Reasonably controlling the relationship between the effective focal length of the second lens and the curvature radii of the object side surface and the image side surface of the second lens is beneficial for balancing the aberration of the optical imaging lens and improving the resolution of the optical imaging lens.

[0051] In an exemplary embodiment, 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 may satisfy: -6 < (R11 + R12) / (R11 - R12) < -1. In an example, -5 < (R11 + R12) / (R11 - R12) < -3. By reasonably controlling the mutual relationship between the radius of curvature of the object side surface and the radius of curvature of the image side surface of the sixth lens, the ratio of the radius of curvature of the object side surface and the radius of curvature of the image side surface of the sixth lens can be constrained within a certain range, ensuring that the sixth lens has an appropriate refractive power, reducing the angle between the chief ray and the optical axis when it enters the imaging surface, and improving the illuminance of the imaging surface.

[0052] In an exemplary embodiment, the central thickness CT5 of the fifth lens on the optical axis, the central thickness CT6 of the sixth lens on the optical axis, and the air gap T56 between the fifth lens and the sixth lens on the optical axis may satisfy: 0.4 < (CT5 + CT6) / T56 < 2. By reasonably controlling the mutual relationship between the central thickness of the fifth lens on the optical axis, the central thickness of the sixth lens on the optical axis, and the air gap between the fifth lens and the sixth lens on the optical axis, it is beneficial to reasonably layout the sizes of the fifth lens and the sixth lens, ensuring that the optical imaging lens has a high resolution while achieving ultra-thinness.

[0053] In an exemplary embodiment, the effective focal length f6 of the sixth lens, the effective focal length f7 of the seventh lens, the radius of curvature R11 of the object side surface of the sixth lens, and the radius of curvature R13 of the object side surface of the seventh lens satisfy: 3 < f6 / R11 + f7 / R13 < 9. In an example, 5.0 < f6 / R11 + f7 / R13 < 7.5. By constraining the ratio of the effective focal length of the sixth lens to the radius of curvature of the object side surface and the ratio of the effective focal length of the seventh lens to the radius of curvature of the object side surface within a reasonable range, it is beneficial for the optical imaging lens to better adjust the light focusing position, improve the light converging ability of the optical imaging lens, and effectively balance the axial aberration of the optical imaging lens.

[0054] In an exemplary embodiment, the effective semi-aperture DT72 of the image side surface of the seventh lens, the effective semi-aperture DT81 of the object side surface of the eighth lens, and the effective semi-aperture DT82 of the image side surface of the eighth lens may satisfy: 1 < DT81 / (DT82 - DT72) < 4.5. By constraining the effective semi-apertures of the seventh lens and the eighth lens, it is beneficial to reduce the influence of off-axis field aberration while ensuring the illuminance of the optical imaging lens.

[0055] In an exemplary embodiment, the minimum refractive index Nmin of all the lenses among the first lens to the eighth lens may satisfy: Nmin > 1.5, and the minimum Abbe number Vmin of all the lenses among the first lens to the eighth lens may satisfy: Vmin < 20. By constraining the minimum value of the dispersion coefficient and the minimum value of the refractive index of the first lens to the eighth lens within a reasonable range, the size layout of the optical imaging lens can be made more reasonable, which is beneficial to improving the processability and use stability of the optical imaging lens. At the same time, the chromatic aberration of the optical imaging lens can be better corrected, ensuring that the optical imaging lens has good imaging quality.

[0056] In an exemplary embodiment, the on-axis distance BFL from the image side of the eighth lens to the imaging surface of the optical imaging lens and the sum ∑CT of the central thicknesses of all the lenses among the first lens to the eighth lens on the optical axis may satisfy: 1 < ∑CT / BFL < 4. In an example, 2.5 < ∑CT / BFL < 3.5. By constraining the ratio of the sum of the central thicknesses of all the lenses among the first lens to the eighth lens on the optical axis to the back focal length of the optical imaging lens within a reasonable range, it is beneficial to ensure that the optical imaging lens is thinned out.

[0057] In an exemplary embodiment, the optical imaging lens may further include a diaphragm, and the diaphragm may be disposed between the object side and the first lens according to actual needs.

[0058] The optical imaging lens according to the above embodiment of the present application may employ multiple lenses, such as eight lenses described above. By reasonably allocating optical parameters such as the refractive power, surface shape, central thickness of each lens, and on-axis spacing between each lens, the optical imaging lens can be thinned out and have a large field of view, balance the on-axis aberration of the optical imaging lens, and improve the resolution and imaging quality of the optical imaging lens.

[0059] In an embodiment of the present application, at least one of the lens surfaces of each lens among the first lens to the eighth lens is an aspherical lens surface. The characteristics of an aspherical lens are that the curvature continuously changes 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, the aberration that appears during imaging can be eliminated as much as possible, thereby improving the imaging quality. Optionally, both the object side and the image side of all the lenses among the first lens to the eighth lens are aspherical lens surfaces.

[0060] 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 imaging lens can be changed to obtain the various results and advantages described in this specification.

[0061] The specific embodiments of the optical imaging lens applicable to the above embodiments will be further described with reference to the accompanying drawings.

[0062] Example 1

[0063] The following refers to Figures 1 to 2D Describe the optical imaging lens according to Embodiment 1 of the present application. Figure 1 The structural schematic diagram of the optical imaging lens 100 according to Embodiment 1 of the present application is shown.

[0064] As Figure 1 shown, the optical imaging lens 100 sequentially includes, from the object side to the image side along the optical axis: a first lens E1, a second lens E2, a third lens E3, a fourth lens E4, a fifth lens E5, a sixth lens E6, a seventh lens E7, and an eighth lens E8. The aperture stop STO can be disposed between the object side and the first lens E1 according to actual needs.

[0065] The first lens E1 has a positive refractive power, its object side surface S1 is a convex surface, and its image side surface S2 is a concave surface. The second lens E2 has a negative refractive power, its object side surface S3 is a convex surface, and its image side surface S4 is a concave surface. The third lens E3 has a negative refractive power, its object side surface S5 is a convex surface, and its image side surface S6 is a concave surface. The fourth lens E4 has a positive refractive power, its object side surface S7 is a convex surface, and its image side surface S8 is a convex surface. The fifth lens E5 has a negative refractive power, its object side surface S9 is a convex surface, and its image side surface S10 is a concave surface. The sixth lens E6 has a negative refractive power, its object side surface S11 is a concave surface, and its image side surface S12 is a convex surface. The seventh lens E7 has a positive refractive power, its object side surface S13 is a convex surface, and its image side surface S14 is a concave surface. The eighth lens E8 has a negative refractive power, its object side surface S15 is a convex surface, and its image side surface S16 is a concave surface. The filter E9 has an object side surface S17 and an image side surface S18. The light from the object sequentially passes through the surfaces S1 to S18 and finally forms an image on the imaging surface S19.

[0066] Table 1 shows the basic parameter table of the optical imaging lens 100 of Embodiment 1, where the units of the radius of curvature, thickness / distance, and focal length are all millimeters (mm).

[0067]

[0068] Table 1

[0069] In this embodiment, the total effective focal length f of the optical imaging lens is 7.55 mm, the on-axis distance TTL between the object side surface of the first lens element and the imaging plane is 10.23 mm, the value of half the diagonal length of the effective pixel area on the imaging plane of the optical imaging lens ImgH is 8.53 mm, the value of half the maximum field of view Semi-FOV of the optical imaging lens is 41.99°, the value of the aperture number Fno of the optical imaging lens is 1.83, the on-axis distance BFL between the image side surface of the eighth lens element and the imaging plane is 1.74 mm, the value of the edge thickness ET5 of the fifth lens element at the maximum effective aperture is 0.38 mm, the value of the edge thickness ET8 of the eighth lens element at the maximum effective aperture is 2.11 mm, the value of the effective half-aperture DT72 of the image side surface of the seventh lens element is 4.83 mm, the value of the effective half-aperture DT81 of the object side surface of the eighth lens element is 5.11 mm, and the value of the effective half-aperture DT82 of the image side surface of the eighth lens element is 7.12 mm.

[0070] In Example 1, the object-side surface and the image-side surface of any lens from the first lens E1 to the eighth lens E8 are both aspherical surfaces. The surface shape x of each aspherical lens can be defined by, but is not limited to, the following aspherical surface formula:

[0071]

[0072] Wherein, x is the distance vector height of the aspheric surface from the vertex of the aspheric surface at a height of h along the optical axis; c is the paraxial curvature of the aspheric surface, c = 1 / R (i.e., 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 aspheric surface. Table 2 shows the high-order coefficients A4, A6, A8, A9, A10, A11, A12, A13, A14, A15, A16, A17, A18, A19, A20, A21, A22, A23, A24, A25, A26, A27, A28, A30, A31, A32, A33, A34, A35, A36, A37, A38, A39, A40, A 10 , A 12 , A 14 , A 16 , A 18 and A 20 .

[0073] Plane number A4 A6 A8 A10 A12 A14 A16 A18 A20 S1 2.6780E-02 3.6830E-03 3.3218E-04 7.7715E-05 9.4367E-05 7.7543E-06 2.8654E-05 8.6290E-06 1.2376E-05 S2 -2.6837E-02 1.4903E-02 -4.0994E-03 1.8323E-03 -4.8067E-04 2.0961E-04 -2.1741E-05 2.7635E-05 -1.1368E-05 S3 -8.4360E-02 3.1029E-02 -5.1486E-03 2.2282E-03 -7.4192E-04 2.1263E-04 1.9902E-05 2.7355E-05 -6.5348E-06 S4 -4.5619E-02 1.6650E-02 -1.9256E-03 9.6601E-04 -3.9741E-04 -5.9819E-05 -2.6841E-05 7.7818E-06 6.7428E-06 S5 -1.6494E-01 2.2708E-03 -8.5782E-04 -9.9660E-06 -5.1156E-04 -3.3340E-04 -1.0431E-04 -5.2200E-05 -7.1027E-06 S6 -1.8108E-01 2.3229E-02 1.7073E-03 6.1761E-05 -4.1314E-04 -1.0422E-04 9.1547E-05 5.7381E-06 9.6612E-06 S7 -1.9255E-01 7.7048E-03 2.2623E-03 1.8539E-03 9.0656E-04 4.5877E-04 1.9407E-04 8.0366E-05 -4.0264E-06 S8 -3.7374E-01 -6.6658E-03 -2.5411E-03 -4.7853E-05 -5.1754E-04 -3.0788E-04 -1.6603E-04 -2.2316E-05 -1.0251E-05 S9 -7.3328E-01 1.7286E-01 3.1196E-02 -1.5712E-03 -3.1819E-03 3.2258E-04 5.1912E-04 4.5706E-04 1.1943E-04 S10 -8.0467E-01 3.5507E-02 3.1685E-02 2.6675E-02 4.8308E-03 2.1941E-03 -2.6817E-04 3.2493E-05 -1.4667E-04 S11 3.4783E-01 -9.0014E-02 -1.2698E-02 2.8756E-02 -1.0335E-03 1.9711E-03 -1.1282E-03 3.4692E-05 -2.1846E-04 S12 -2.0737E-01 2.5506E-01 -4.8787E-02 1.9990E-02 -9.8480E-03 1.6729E-04 -6.8790E-04 3.1833E-04 9.9704E-05 S13 -2.0243E+00 -6.1175E-02 6.6308E-02 9.9988E-03 6.8252E-04 -8.3076E-03 6.2054E-04 2.5561E-04 -7.1598E-05 S14 -9.2263E-01 -9.0778E-02 2.2338E-01 -1.2760E-01 2.9011E-02 -1.9933E-02 1.9523E-02 -6.7265E-03 8.5042E-04 S15 -5.7961E+00 1.6777E+00 -5.7244E-01 1.5937E-01 -3.2981E-02 -1.4077E-02 1.2209E-02 -5.9017E-03 9.2219E-04 S16 -1.3304E+01 2.6274E+00 -1.0455E+00 4.1698E-01 -1.7321E-01 7.0776E-02 -2.8731E-02 1.0976E-02 -6.2828E-03

[0074] Table 2

[0075] Figure 2A The axial chromatic aberration curve of the optical imaging lens 100 of Example 1 is shown, which indicates the deviation of the focal point of light of different wavelengths after passing through the optical imaging lens 100. Figure 2B The astigmatism curve of the optical imaging lens 100 of Example 1 is shown, which represents the meridional image curvature and sagittal image curvature corresponding to different image heights. Figure 2C The distortion curve of the optical imaging lens 100 of Example 1 is shown, which represents the distortion values corresponding to different image heights.Figure 2D Shows the longitudinal chromatic aberration curve of the optical imaging lens 100 of Embodiment 1, which represents the deviation of different image heights on the imaging surface after light passes through the lens. According to Figures 2A to 2D it can be known that the optical imaging lens 100 given in Embodiment 1 can achieve good imaging quality.

[0076] Example 2

[0077] The following refers to Figures 3 to 4D Describe the optical imaging lens according to Embodiment 2 of the present application. Figure 3 Shows a schematic structural diagram of the optical imaging lens 200 according to Embodiment 2 of the present application.

[0078] As Figure 3 shown, the optical imaging lens 200 sequentially includes, from the object side to the image side along the optical axis: a first lens E1, a second lens E2, a third lens E3, a fourth lens E4, a fifth lens E5, a sixth lens E6, a seventh lens E7, and an eighth lens E8. The aperture stop STO can be arranged between the object side and the first lens E1 according to actual needs.

[0079] The first lens E1 has a positive refractive power, its object side surface S1 is a convex surface, and its image side surface S2 is a concave surface. The second lens E2 has a negative refractive power, its object side surface S3 is a convex surface, and its image side surface S4 is a concave surface. The third lens E3 has a negative refractive power, its object side surface S5 is a convex surface, and its image side surface S6 is a concave surface. The fourth lens E4 has a positive refractive power, its object side surface S7 is a concave surface, and its image side surface S8 is a convex surface. The fifth lens E5 has a negative refractive power, its object side surface S9 is a concave surface, and its image side surface S10 is a concave surface. The sixth lens E6 has a negative refractive power, its object side surface S11 is a concave surface, and its image side surface S12 is a convex surface. The seventh lens E7 has a positive refractive power, its object side surface S13 is a convex surface, and its image side surface S14 is a convex surface. The eighth lens E8 has a negative refractive power, its object side surface S15 is a convex surface, and its image side surface S16 is a concave surface. The filter E9 has an object side surface S17 and an image side surface S18. Light from the object sequentially passes through the surfaces S1 to S18 and finally forms an image on the imaging surface S19.

[0080] Table 3 shows the basic parameter table of the optical imaging lens 200 of Embodiment 2, where the units of the radius of curvature, thickness / distance, and focal length are all millimeters (mm).

[0081]

[0082] Table 3

[0083] In this embodiment, the value of the total effective focal length f of the optical imaging lens is 7.71 mm, the value of the on-axis distance TTL from the object side surface of the first lens to the imaging surface is 9.98 mm, the value of half of the diagonal length ImgH of the effective pixel region on the imaging surface of the optical imaging lens is 8.53 mm, the value of half of the maximum field of view Semi-FOV of the optical imaging lens is 45.42°, the value of the f-number Fno of the optical imaging lens is 1.83, the value of the on-axis distance BFL from the image side surface of the eighth lens to the imaging surface is 1.86 mm, the value of the edge thickness ET5 at the maximum effective aperture of the fifth lens is 0.34 mm, the value of the edge thickness ET8 at the maximum effective aperture of the eighth lens is 0.95 mm, the value of the effective semi-aperture DT72 of the image side surface of the seventh lens is 4.97 mm, the value of the effective semi-aperture DT81 of the object side surface of the eighth lens is 5.72 mm, and the value of the effective semi-aperture DT82 of the image side surface of the eighth lens is 6.63 mm.

[0084] In Embodiment 2, the object side surface and the image side surface of any one of the first lens E1 to the eighth lens E8 are aspherical surfaces. Table 4 gives the higher-order term coefficients A4, A6, A8, A 10 , A 12 , A 14 , A 16 , A 18 , A 20 , A 22 , A 24 , A 26 , A 28 , and A 30 that can be used for the aspherical mirror surfaces S1 - S16 in Embodiment 2.

[0085] Plane number A4 A6 A8 A10 A12 A14 A16 S1 1.7366E-02 1.2941E-03 2.4476E-04 1.7015E-04 3.5103E-04 2.5416E-04 2.3662E-04 S2 -3.2528E-02 9.5538E-03 -2.3295E-03 1.1465E-03 -4.3288E-06 1.0550E-04 -3.1761E-05 S3 -7.9864E-02 2.1459E-02 -2.0558E-03 2.2036E-03 2.1564E-04 2.1015E-04 1.1102E-07 S4 -4.2016E-02 1.0793E-02 -9.8761E-04 1.1141E-03 2.7436E-04 1.8401E-04 5.9557E-05 S5 -1.4596E-01 3.8894E-04 -6.2667E-04 2.9322E-04 -3.2021E-05 7.0153E-05 -4.0842E-07 S6 -1.6300E-01 1.7094E-02 2.1957E-03 8.6031E-04 -1.5167E-04 7.1140E-05 -4.8969E-05 S7 -1.4962E-01 -6.4118E-04 2.3091E-04 1.1690E-03 2.3217E-04 1.7333E-04 -7.7240E-05 S8 -3.4328E-01 6.9030E-04 -3.0967E-03 -6.0188E-04 -1.7294E-04 -1.3542E-04 -1.4226E-04 S9 -7.5140E-01 1.8289E-01 3.2273E-02 -1.8107E-03 -3.3127E-03 1.6244E-03 -6.7667E-05 S10 -7.9144E-01 3.7409E-02 3.9686E-02 2.5085E-02 4.9213E-03 3.2833E-03 -7.3570E-05 S11 3.1755E-01 -7.7277E-02 -9.5524E-03 3.5878E-02 1.0378E-03 2.5541E-03 -2.5904E-03 S12 -1.0798E-01 2.7022E-01 -5.2933E-02 1.7912E-02 -1.2793E-02 1.0614E-03 3.5972E-04 S13 -2.6755E+00 1.1183E-01 1.2071E-01 -1.7463E-03 -1.2351E-02 -1.2088E-02 4.9423E-03 S14 -1.0796E+00 -9.8270E-02 2.0875E-01 -1.6791E-01 2.0535E-02 -1.9447E-02 1.4219E-02 S15 -6.3937E+00 1.9783E+00 -7.0087E-01 2.1576E-01 -5.4076E-02 -4.1746E-03 1.4685E-02 S16 -1.3334E+01 2.5524E+00 -9.9761E-01 3.9884E-01 -1.5145E-01 4.5891E-02 -3.5305E-02 Plane number A18 A20 A22 A24 A26 A28 A30 S1 1.6160E-04 1.3600E-04 7.8410E-05 4.6154E-05 7.5996E-06 -2.7338E-06 -4.8203E-06 S2 -6.3554E-05 -7.5433E-05 -7.5062E-05 -6.0678E-05 -5.2975E-05 -4.0772E-05 -2.2698E-05 S3 -6.7198E-05 -1.0190E-04 -1.0051E-04 -7.5096E-05 -4.6184E-05 -2.5007E-05 -1.0984E-05 S4 6.9679E-07 -3.7057E-05 -5.3108E-05 -5.5612E-05 -4.6356E-05 -2.8485E-05 -1.0410E-05 S5 1.9067E-05 -5.7638E-06 3.0914E-06 -6.2849E-06 4.4318E-07 -4.6451E-06 3.6626E-06 S6 3.3824E-05 -2.2013E-05 9.8212E-06 -9.5642E-06 8.9480E-06 -5.1769E-06 2.4282E-06 S7 6.2567E-05 -3.5035E-05 1.5105E-05 -7.3974E-06 3.4548E-05 1.0890E-05 1.4870E-05 S8 -5.4402E-05 1.4691E-04 -1.2564E-05 5.1991E-05 -4.8896E-05 1.8184E-05 -9.2155E-06 S9 2.6640E-05 -2.8911E-04 1.1945E-04 1.3570E-04 -1.9522E-04 -2.3227E-04 -1.8844E-04 S10 -1.3554E-07 -8.1654E-04 -4.9915E-04 -3.1207E-04 -1.1586E-04 -1.4842E-05 -2.3040E-05 S11 1.4826E-03 -2.8200E-04 -1.7449E-05 -7.4713E-05 -1.2303E-04 4.8819E-05 -7.0394E-07 S12 2.7940E-03 -1.6381E-03 -1.1510E-04 1.1517E-04 4.8801E-05 2.8532E-05 -8.8945E-05 S13 1.0239E-03 -2.0089E-04 6.3049E-05 1.0113E-05 -2.0674E-05 -1.1453E-05 -9.8277E-06 S14 -1.3540E-02 1.3451E-04 -2.1283E-03 -1.5923E-03 -1.5388E-03 -8.4583E-04 -4.4570E-04 S15 -9.1520E-03 2.6722E-03 1.3087E-05 -5.8089E-05 -3.0046E-05 2.3071E-05 -3.8890E-05 S16 4.1166E-03 -6.2447E-03 3.8216E-04 -6.1555E-04 -3.0485E-04 -1.1309E-03 -7.9777E-04

[0086] Table 4

[0087] Figure 4A shows the axial chromatic aberration curve of the optical imaging lens 200 in Embodiment 2, which represents the deviation of the convergence points of light rays with different wavelengths after passing through the optical imaging lens 200. Figure 4B shows the astigmatism curve of the optical imaging lens 200 in Embodiment 2, which represents the meridional image plane curvature and the sagittal image plane curvature corresponding to different image heights. Figure 4C shows the distortion curve of the optical imaging lens 200 in Embodiment 2, which represents the distortion magnitude values corresponding to different image heights. Figure 4D shows the lateral chromatic aberration curve of the optical imaging lens 200 in Embodiment 2, which represents the deviation of different image heights on the imaging surface after the light rays pass through the lens. According to Figures 4A to 4D , it can be known that the optical imaging lens 200 given in Embodiment 2 can achieve good imaging quality.

[0088] Example 3

[0089] Refer to the following Figures 5 to 6D to describe the optical imaging lens according to Embodiment 3 of the present application. Figure 5 FIG. shows a schematic structural diagram of an optical imaging lens 300 according to Embodiment 3 of the present application.

[0090] As Figure 5 shown, the optical imaging lens 300 sequentially includes, from the object side to the image side along the optical axis: a first lens E1, a second lens E2, a third lens E3, a fourth lens E4, a fifth lens E5, a sixth lens E6, a seventh lens E7, and an eighth lens E8. The aperture stop STO can be disposed between the object side and the first lens E1 according to actual needs.

[0091] The first lens E1 has a positive refractive power, its object side surface S1 is a convex surface, and its image side surface S2 is a concave surface. The second lens E2 has a negative refractive power, its object side surface S3 is a convex surface, and its image side surface S4 is a concave surface. The third lens E3 has a negative refractive power, its object side surface S5 is a convex surface, and its image side surface S6 is a concave surface. The fourth lens E4 has a positive refractive power, its object side surface S7 is a concave surface, and its image side surface S8 is a convex surface. The fifth lens E5 has a negative refractive power, its object side surface S9 is a concave surface, and its image side surface S10 is a convex surface. The sixth lens E6 has a negative refractive power, its object side surface S11 is a concave surface, and its image side surface S12 is a convex surface. The seventh lens E7 has a positive refractive power, its object side surface S13 is a convex surface, and its image side surface S14 is a concave surface. The eighth lens E8 has a negative refractive power, its object side surface S15 is a convex surface, and its image side surface S16 is a concave surface. The filter E9 has an object side surface S17 and an image side surface S18. Light from the object sequentially passes through the surfaces S1 to S18 and finally forms an image on the imaging surface S19.

[0092] Table 5 shows the basic parameter table of the optical imaging lens 300 of Embodiment 3, where the units of the radius of curvature, thickness / distance, and focal length are all millimeters (mm).

[0093]

[0094]

[0095] Table 5

[0096] In this embodiment, the value of the total effective focal length f of the optical imaging lens is 8.15 mm, the value of the on-axis distance TTL from the object side surface of the first lens to the imaging surface is 10.27 mm, the value of half of the diagonal length ImgH of the effective pixel region on the imaging surface of the optical imaging lens is 8.53 mm, the value of half of the maximum field of view Semi-FOV of the optical imaging lens is 40.39°, the value of the aperture number Fno of the optical imaging lens is 1.83, the value of the on-axis distance BFL from the image side surface of the eighth lens to the imaging surface is 1.91 mm, the value of the edge thickness ET5 at the maximum effective aperture of the fifth lens is 0.32 mm, the value of the edge thickness ET8 at the maximum effective aperture of the eighth lens is 1.25 mm, the value of the effective semi-aperture DT72 of the image side surface of the seventh lens is 4.74 mm, the value of the effective semi-aperture DT81 of the object side surface of the eighth lens is 5.21 mm, and the value of the effective semi-aperture DT82 of the image side surface of the eighth lens is 6.56 mm.

[0097] In Embodiment 3, the object side surface and the image side surface of any one of the first lens E1 to the eighth lens E8 are aspherical surfaces. Table 6 gives the higher-order term coefficients A4, A6, A8, A 10 , A 12 , A 14 , A 16 , A 18 , and A 20 that can be used for the aspherical mirror surfaces S1 - S16 in Embodiment 3.

[0098] Plane number A4 A6 A8 A10 A12 A14 A16 A18 A20 S1 2.2777E-02 4.8914E-03 1.3928E-03 5.4724E-04 2.3983E-04 7.8506E-05 2.7469E-05 5.4404E-06 4.7175E-06 S2 -3.0229E-02 1.6880E-02 -3.9013E-03 2.1989E-03 -5.4521E-04 2.4177E-04 -3.9975E-05 2.5197E-05 -6.8907E-06 S3 -8.3354E-02 3.1409E-02 -6.6266E-03 2.5218E-03 -9.3993E-04 1.9951E-04 -5.5077E-05 1.8198E-05 -3.8294E-06 S4 -4.8928E-02 1.6439E-02 -2.5356E-03 8.4131E-04 -3.4599E-04 -1.4173E-05 -3.4827E-05 -7.6740E-06 -6.2793E-06 S5 -1.6393E-01 2.6310E-03 -6.2194E-04 -2.7429E-04 -4.1470E-04 -1.7725E-04 -8.0751E-05 -2.5336E-05 -1.0780E-05 S6 -1.8020E-01 2.2260E-02 2.5133E-03 3.5650E-04 -2.8844E-04 -1.3480E-04 -4.5705E-05 -7.7444E-06 7.7943E-08 S7 -1.8972E-01 7.2665E-03 2.0167E-03 2.3069E-03 8.5704E-04 1.1493E-04 -3.8873E-05 -2.9415E-05 -1.4022E-05 S8 -3.6888E-01 -3.8993E-03 -3.6706E-03 6.1056E-04 1.1556E-04 -1.8302E-04 -1.5458E-04 -5.4107E-05 -2.2390E-05 S9 -7.3220E-01 1.7045E-01 3.4447E-02 9.0527E-05 -3.5987E-03 6.4710E-05 3.2992E-04 1.4482E-04 -1.6897E-04 S10 -8.0368E-01 3.9873E-02 3.2644E-02 2.4053E-02 4.5452E-03 1.6573E-03 3.5265E-04 3.8641E-04 -1.1713E-04 S11 2.9953E-01 -7.9010E-02 -1.6602E-02 3.1181E-02 1.5647E-03 2.2529E-03 -1.5067E-03 1.2038E-03 -3.2819E-04 S12 -1.5727E-01 2.4800E-01 -4.9089E-02 1.9016E-02 -1.1526E-02 -1.7724E-04 -4.0731E-04 1.9754E-03 -9.3953E-04 S13 -2.1073E+00 -4.1256E-02 6.0479E-02 9.4703E-03 2.8846E-03 -8.7708E-03 2.2450E-04 4.8416E-04 -1.3104E-04 S14 -9.5681E-01 -1.2091E-01 2.3413E-01 -1.2768E-01 3.0433E-02 -1.8967E-02 1.6720E-02 -8.0330E-03 1.5609E-03 S15 -5.8119E+00 1.6904E+00 -5.7582E-01 1.5893E-01 -2.9920E-02 -1.2622E-02 1.3038E-02 -5.4784E-03 1.1198E-03 S16 -1.1599E+01 2.4581E+00 -9.2319E-01 3.4853E-01 -1.3308E-01 4.7619E-02 -2.1730E-02 7.8986E-03 -2.6735E-03

[0099] Table 6

[0100] Figure 6A shows the axial chromatic aberration curve of the optical imaging lens 300 in Embodiment 3, which represents the deviation of the converging points of light rays with different wavelengths after passing through the optical imaging lens 300. Figure 6B shows the astigmatism curve of the optical imaging lens 300 in Embodiment 3, which represents the meridional image plane curvature and sagittal image plane curvature corresponding to different image heights. Figure 6C shows the distortion curve of the optical imaging lens 300 in Embodiment 3, which represents the distortion magnitude values corresponding to different image heights. Figure 6D shows the lateral chromatic aberration curve of the optical imaging lens 300 in Embodiment 3, which represents the deviation of different image heights on the imaging surface after the light rays pass through the lens. According to Figures 6A to 6D , it can be seen that the optical imaging lens 300 given in Embodiment 3 can achieve good imaging quality.

[0101] Example 4

[0102] Refer to the following Figures 7 to 8DDescribe the optical imaging lens according to Embodiment 4 of the present application. Figure 7 FIG. 2 shows a schematic structural diagram of an optical imaging lens 400 according to Embodiment 4 of the present application.

[0103] As Figure 7 shown, the optical imaging lens 400 sequentially includes, from the object side to the image side along the optical axis: a first lens E1, a second lens E2, a third lens E3, a fourth lens E4, a fifth lens E5, a sixth lens E6, a seventh lens E7, and an eighth lens E8. The aperture stop STO can be disposed between the object side and the first lens E1 according to actual needs.

[0104] The first lens E1 has a positive refractive power, its object surface S1 is convex, and its image surface S2 is concave. The second lens E2 has a negative refractive power, its object surface S3 is convex, and its image surface S4 is concave. The third lens E3 has a negative refractive power, its object surface S5 is convex, and its image surface S6 is concave. The fourth lens E4 has a positive refractive power, its object surface S7 is convex, and its image surface S8 is convex. The fifth lens E5 has a negative refractive power, its object surface S9 is convex, and its image surface S10 is concave. The sixth lens E6 has a negative refractive power, its object surface S11 is concave, and its image surface S12 is convex. The seventh lens E7 has a positive refractive power, its object surface S13 is convex, and its image surface S14 is convex. The eighth lens E8 has a negative refractive power, its object surface S15 is convex, and its image surface S16 is concave. The filter E9 has an object surface S17 and an image surface S18. Light from the object sequentially passes through the surfaces S1 to S18 and finally forms an image on the imaging surface S19.

[0105] Table 7 shows the basic parameter table of the optical imaging lens 400 of Embodiment 4, where the units of the radius of curvature, thickness / distance, and focal length are all millimeters (mm).

[0106]

[0107] Table 7

[0108] In this embodiment, the value of the total effective focal length f of the optical imaging lens is 6.81 mm, the value of the on-axis distance TTL from the object side surface of the first lens to the imaging surface is 9.00 mm, the value of half of the diagonal length ImgH of the effective pixel region on the imaging surface of the optical imaging lens is 7.76 mm, the value of half of the maximum field of view Semi-FOV of the optical imaging lens is 40.68°, the value of the f-number Fno of the optical imaging lens is 1.83, the value of the on-axis distance BFL from the image side surface of the eighth lens to the imaging surface is 1.40 mm, the value of the edge thickness ET5 at the maximum effective aperture of the fifth lens is 0.18 mm, the value of the edge thickness ET8 at the maximum effective aperture of the eighth lens is 1.34 mm, the value of the effective semi-aperture DT72 of the image side surface of the seventh lens is 4.01 mm, the value of the effective semi-aperture DT81 of the object side surface of the eighth lens is 4.20 mm, and the value of the effective semi-aperture DT82 of the image side surface of the eighth lens is 5.88 mm.

[0109] In Embodiment 4, the object side surface and the image side surface of any one of the first lens E1 to the eighth lens E8 are aspherical surfaces. Table 8 gives the higher-order term coefficients A4, A6, A8, A 10 、A 12 、A 14 、A 16 、A 18 and A 20 that can be used for the aspherical surfaces S1 - S16 in Embodiment 4.

[0110] Plane number A4 A6 A8 A10 A12 A14 A16 A18 A20 S1 2.5789E-02 1.0461E-04 2.5439E-04 1.2731E-03 6.6119E-04 -2.7945E-05 -2.2680E-04 -1.3024E-04 -3.2154E-05 S2 -8.4632E-03 -1.5128E-03 5.4719E-05 3.2373E-03 -9.4989E-05 -9.0176E-04 -1.1063E-03 -4.6775E-04 -1.1696E-04 S3 -8.2783E-02 2.3442E-02 -5.1968E-03 2.9435E-03 4.4263E-04 2.0434E-04 -4.9561E-04 -2.4158E-04 -7.6128E-05 S4 -3.9914E-02 2.0612E-02 -4.3347E-04 3.4410E-04 -3.9905E-04 -8.4255E-05 -6.7917E-05 -2.3035E-05 -9.0522E-06 S5 -1.7210E-01 1.7966E-03 -9.7970E-04 -4.7485E-04 -6.8713E-04 -2.7039E-04 -1.2645E-04 -3.4984E-05 -7.9111E-06 S6 -1.8041E-01 2.4509E-02 -1.4897E-03 -4.8092E-04 -4.9905E-04 -6.0945E-05 -3.7016E-05 -6.7596E-06 8.5216E-06 S7 -1.8417E-01 1.1111E-02 2.6948E-04 2.3771E-03 1.1593E-03 1.4268E-04 -1.2595E-04 -1.1899E-04 -3.2669E-05 S8 -3.8956E-01 -1.3006E-02 -4.0861E-03 -4.1270E-04 1.0025E-03 5.4597E-04 2.6934E-04 1.0831E-04 4.3624E-06 S9 -7.2628E-01 1.7288E-01 3.1047E-02 -3.2874E-03 1.1044E-04 4.2002E-04 -6.6087E-04 6.1146E-04 -1.6383E-04 S10 -8.4105E-01 3.6361E-02 4.1282E-02 2.3807E-02 2.8645E-03 2.7508E-03 -1.1752E-03 6.0576E-04 -1.0476E-04 S11 3.6111E-01 -1.0602E-01 -4.2467E-03 2.9379E-02 -7.0852E-03 6.3051E-03 -2.6777E-03 8.8977E-04 -1.1485E-04 S12 -1.3835E-01 2.5864E-01 -6.4101E-02 1.8103E-02 -1.0781E-02 5.2519E-03 -3.4948E-03 1.8138E-03 -4.4716E-04 S13 -2.6111E+00 -1.2125E-01 7.7392E-02 5.9058E-03 1.0120E-02 -4.0282E-03 -2.1688E-03 1.6354E-03 6.9639E-04 S14 -1.8325E+00 -4.0449E-01 3.4587E-01 -1.2631E-01 2.2732E-02 -2.9580E-02 4.5790E-02 1.1102E-02 2.4606E-03 S15 -7.2666E+00 1.8022E+00 -5.6769E-01 2.7906E-01 -1.4786E-01 -1.1079E-02 4.5587E-02 3.8835E-02 2.1022E-02 S16 -1.2517E+01 2.8177E+00 -1.1597E+00 4.4609E-01 -1.9638E-01 7.6425E-02 -3.0222E-02 9.1920E-03 -3.2724E-03

[0111] Table 8

[0112] Figure 8A shows the axial chromatic aberration curve of the optical imaging lens 400 in Embodiment 4, which represents the deviation of the convergence points of light rays with different wavelengths after passing through the optical imaging lens 400. Figure 8B shows the astigmatism curve of the optical imaging lens 400 in Embodiment 4, which represents the meridional image plane curvature and sagittal image plane curvature corresponding to different image heights. Figure 8C shows the distortion curve of the optical imaging lens 400 in Embodiment 4, which represents the distortion magnitude values corresponding to different image heights. Figure 8D shows the lateral chromatic aberration curve of the optical imaging lens 400 in Embodiment 4, which represents the deviation of different image heights on the imaging surface after the light rays pass through the lens. According to Figures 8A to 8D it can be seen that the optical imaging lens 400 given in Embodiment 4 can achieve good imaging quality.

[0113] Example 5

[0114] The following refers to Figures 9 to 10DDescribe the optical imaging lens according to Embodiment 5 of the present application. Figure 9 Fig. 2 shows a schematic structural diagram of an optical imaging lens 500 according to Embodiment 5 of the present application.

[0115] As Figure 9 shown, the optical imaging lens 500 sequentially includes, from the object side to the image side along the optical axis: a first lens E1, a second lens E2, a third lens E3, a fourth lens E4, a fifth lens E5, a sixth lens E6, a seventh lens E7, and an eighth lens E8. The aperture stop STO can be disposed between the object side and the first lens E1 according to actual needs.

[0116] The first lens E1 has a positive refractive power, its object surface S1 is convex, and its image surface S2 is concave. The second lens E2 has a negative refractive power, its object surface S3 is convex, and its image surface S4 is concave. The third lens E3 has a negative refractive power, its object surface S5 is convex, and its image surface S6 is concave. The fourth lens E4 has a positive refractive power, its object surface S7 is convex, and its image surface S8 is convex. The fifth lens E5 has a negative refractive power, its object surface S9 is concave, and its image surface S10 is convex. The sixth lens E6 has a negative refractive power, its object surface S11 is concave, and its image surface S12 is convex. The seventh lens E7 has a positive refractive power, its object surface S13 is convex, and its image surface S14 is concave. The eighth lens E8 has a negative refractive power, its object surface S15 is convex, and its image surface S16 is concave. The filter E9 has an object surface S17 and an image surface S18. Light from the object sequentially passes through the surfaces S1 to S18 and finally forms an image on the imaging surface S19.

[0117] Table 9 shows the basic parameter table of the optical imaging lens 500 of Embodiment 5, where the units of the radius of curvature, thickness / distance, and focal length are all millimeters (mm).

[0118]

[0119] Table 9

[0120] In this embodiment, the value of the total effective focal length f of the optical imaging lens is 8.32 mm, the value of the on-axis distance TTL from the object side surface of the first lens to the imaging surface is 10.37 mm, the value of half of the diagonal length ImgH of the effective pixel area on the imaging surface of the optical imaging lens is 9.15 mm, the value of half of the maximum field of view Semi-FOV of the optical imaging lens is 41.67°, the value of the f-number Fno of the optical imaging lens is 1.83, the value of the on-axis distance BFL from the image side surface of the eighth lens to the imaging surface is 1.91 mm, the value of the edge thickness ET5 at the maximum effective aperture of the fifth lens is 0.34 mm, the value of the edge thickness ET8 at the maximum effective aperture of the eighth lens is 0.94 mm, the value of the effective semi-aperture DT72 of the image side surface of the seventh lens is 4.92 mm, the value of the effective semi-aperture DT81 of the object side surface of the eighth lens is 5.08 mm, and the value of the effective semi-aperture DT82 of the image side surface of the eighth lens is 6.28 mm.

[0121] In Embodiment 5, the object side surface and the image side surface of any one of the first lens E1 to the eighth lens E8 are aspherical surfaces. Table 10 gives the higher-order term coefficients A4, A6, A8, A 10 , A 12 , A 14 , A 16 , A 18 , and A 20 that can be used for the aspherical surfaces S1 - S16 in Embodiment 5.

[0122] Plane number A4 A6 A8 A10 A12 A14 A16 A18 A20 S1 2.0699E-02 1.8392E-03 1.1647E-04 4.2022E-05 1.9779E-05 3.1044E-06 -7.2442E-07 1.3262E-06 -2.4786E-09 S2 -1.6143E-02 1.0741E-02 -3.1231E-03 1.6541E-03 -2.8924E-04 2.9898E-04 3.0889E-06 3.9742E-05 -3.8911E-06 S3 -7.0567E-02 2.8546E-02 -4.6643E-03 2.0984E-03 -4.3776E-04 3.2880E-04 1.6861E-05 4.1983E-05 -4.5257E-06 S4 -3.0868E-02 1.6325E-02 -1.3354E-03 5.2009E-04 -2.6939E-04 -2.5499E-05 -3.3571E-05 -5.0794E-06 -4.7197E-06 S5 -1.5984E-01 5.4453E-03 7.7350E-04 -2.1944E-04 -4.0333E-04 -1.4784E-04 -6.2428E-05 -1.6115E-05 -1.0784E-05 S6 -1.8410E-01 2.4034E-02 4.0210E-03 -1.1267E-04 -4.9226E-04 -1.0639E-04 -1.4072E-05 1.0311E-05 -4.5826E-07 S7 -1.8481E-01 7.4665E-03 1.9844E-03 4.5346E-04 2.1100E-04 2.2505E-04 1.2420E-04 5.9683E-05 1.5936E-05 S8 -3.6257E-01 -1.2370E-02 -4.7949E-03 -1.7985E-03 -9.3025E-04 -3.0880E-04 -1.4315E-04 -2.6132E-05 -4.4232E-06 S9 -7.3814E-01 1.6458E-01 3.6590E-02 1.7622E-03 -2.3706E-03 1.5570E-04 -3.1582E-04 6.0942E-05 -1.1632E-05 S10 -8.0881E-01 3.4718E-02 2.9516E-02 2.3182E-02 5.3938E-03 2.8338E-03 3.6257E-04 2.4433E-04 -4.0617E-05 S11 2.7781E-01 -8.3740E-02 -1.6641E-02 2.8102E-02 8.2585E-04 2.4183E-03 -1.1992E-03 5.9877E-04 -2.3004E-04 S12 -1.5169E-01 2.3653E-01 -4.4277E-02 1.8794E-02 -1.2020E-02 -3.9457E-04 -1.0937E-03 1.2926E-03 -6.9956E-04 S13 -2.1565E+00 -3.6933E-02 3.7479E-02 1.0772E-02 4.4843E-03 -4.7052E-03 -9.7334E-04 -3.7866E-05 -4.5037E-04 S14 -9.1002E-01 -9.9387E-02 2.3009E-01 -1.2477E-01 3.1735E-02 -2.0014E-02 1.5225E-02 -7.1268E-03 1.3076E-03 S15 -5.8910E+00 1.7018E+00 -5.6687E-01 1.5859E-01 -3.0041E-02 -9.3265E-03 1.0632E-02 -6.3084E-03 1.8050E-03 S16 -1.1754E+01 2.2858E+00 -9.8143E-01 3.0746E-01 -1.4816E-01 4.1697E-02 -2.2715E-02 4.7331E-03 -1.8066E-03

[0123] Table 10

[0124] Figure 10A shows the axial chromatic aberration curve of the optical imaging lens 500 in Embodiment 5, which represents the deviation of the convergence points of light rays with different wavelengths after passing through the optical imaging lens 500. Figure 10B shows the astigmatism curve of the optical imaging lens 500 in Embodiment 5, which represents the meridional image plane curvature and the sagittal image plane curvature corresponding to different image heights. Figure 10C shows the distortion curve of the optical imaging lens 500 in Embodiment 5, which represents the distortion magnitude values corresponding to different image heights. Figure 10D shows the lateral chromatic aberration curve of the optical imaging lens 500 in Embodiment 5, which represents the deviation of different image heights on the imaging surface after the light rays pass through the lens. According to Figures 10A to 10D , it can be known that the optical imaging lens 500 given in Embodiment 5 can achieve good imaging quality.

[0125] Example 6

[0126] The following refers to Figures 11 to 12DDescribe the optical imaging lens according to Embodiment 6 of the present application. Figure 11 FIG. 2 shows a schematic structural diagram of an optical imaging lens 600 according to Embodiment 6 of the present application.

[0127] As Figure 11 shown, the optical imaging lens 600 sequentially includes, from the object side to the image side along the optical axis: a first lens E1, a second lens E2, a third lens E3, a fourth lens E4, a fifth lens E5, a sixth lens E6, a seventh lens E7, and an eighth lens E8. The aperture stop STO can be disposed between the object side and the first lens E1 according to actual needs.

[0128] The first lens E1 has a positive refractive power, its object surface S1 is convex, and its image surface S2 is concave. The second lens E2 has a negative refractive power, its object surface S3 is convex, and its image surface S4 is concave. The third lens E3 has a negative refractive power, its object surface S5 is convex, and its image surface S6 is concave. The fourth lens E4 has a positive refractive power, its object surface S7 is convex, and its image surface S8 is convex. The fifth lens E5 has a negative refractive power, its object surface S9 is convex, and its image surface S10 is concave. The sixth lens E6 has a negative refractive power, its object surface S11 is concave, and its image surface S12 is convex. The seventh lens E7 has a positive refractive power, its object surface S13 is convex, and its image surface S14 is concave. The eighth lens E8 has a negative refractive power, its object surface S15 is convex, and its image surface S16 is concave. The filter E9 has an object surface S17 and an image surface S18. The light from the object sequentially passes through the surfaces S1 to S18 and finally forms an image on the imaging surface S19.

[0129] Table 11 shows the basic parameter table of the optical imaging lens 600 of Embodiment 6, where the units of the radius of curvature, thickness / distance, and focal length are all millimeters (mm).

[0130]

[0131] Table 11

[0132] In this embodiment, the value of the total effective focal length f of the optical imaging lens is 6.04 mm, the value of the on-axis distance TTL from the object side surface of the first lens to the imaging surface is 8.20 mm, the value of half of the diagonal length ImgH of the effective pixel region on the imaging surface of the optical imaging lens is 8.30 mm, the value of half of the maximum field of view angle Semi-FOV of the optical imaging lens is 42.59°, the value of the aperture number Fno of the optical imaging lens is 1.83, the value of the on-axis distance BFL from the image side surface of the eighth lens to the imaging surface is 1.35 mm, the value of the edge thickness ET5 at the maximum effective aperture of the fifth lens is 0.27 mm, the value of the edge thickness ET8 at the maximum effective aperture of the eighth lens is 1.18 mm, the value of the effective semi-aperture DT72 of the image side surface of the seventh lens is 3.72 mm, the value of the effective semi-aperture DT81 of the object side surface of the eighth lens is 4.26 mm, and the value of the effective semi-aperture DT82 of the image side surface of the eighth lens is 5.98 mm.

[0133] In Embodiment 6, the object side surface and the image side surface of any one of the first lens E1 to the eighth lens E8 are aspherical surfaces. Table 12 gives the higher-order term coefficients A4, A6, A8, A 10 、A 12 、A 14 、A 16 、A 18 and A 20 that can be used for each of the aspherical mirror surfaces S1 - S16 in Embodiment 6.

[0134] Plane number A4 A6 A8 A10 A12 A14 A16 A18 A20 S1 3.3632E-02 8.4434E-03 -1.0902E-03 -6.4830E-04 6.5993E-04 8.7850E-04 4.4557E-04 1.0847E-04 2.6339E-06 S2 -3.5810E-02 1.8701E-02 -6.2292E-03 2.4835E-03 -5.0934E-04 -2.9796E-04 -5.3510E-04 -2.1874E-04 -5.1378E-05 S3 -9.9272E-02 2.8493E-02 -2.8739E-03 3.9638E-03 -1.4034E-03 -1.4206E-03 -1.0416E-03 -3.2809E-04 -4.7899E-05 S4 -3.4847E-02 1.6241E-02 -3.0957E-03 -4.1894E-04 -1.1563E-04 4.8800E-04 3.9342E-04 1.6001E-04 3.5000E-05 S5 -1.8497E-01 -6.8178E-05 1.0436E-03 4.7038E-04 -1.4722E-03 -1.0048E-03 -4.0586E-04 -7.3329E-05 -3.0009E-06 S6 -1.7548E-01 2.5284E-02 1.0558E-03 3.2811E-04 -1.4643E-03 -3.5417E-04 1.6419E-04 1.7218E-04 4.6624E-05 S7 -1.8235E-01 7.0931E-03 -1.2091E-03 1.9384E-03 2.0092E-03 1.0892E-03 7.9559E-04 4.1718E-04 1.6119E-04 S8 -3.9866E-01 -8.1241E-03 2.5286E-03 -1.5939E-03 7.0015E-04 -3.0090E-04 -7.9874E-04 -5.5753E-04 -1.9085E-04 S9 -6.5771E-01 1.9433E-01 1.9848E-02 -8.7920E-03 4.1637E-03 -1.3745E-03 -1.2549E-03 1.1424E-03 1.1248E-04 S10 -9.0038E-01 1.1563E-02 5.3184E-02 2.7114E-02 3.1766E-03 1.1883E-03 -9.6943E-04 1.1975E-03 2.7364E-04 S11 3.4079E-01 -1.3832E-01 2.1684E-03 3.1178E-02 -6.8653E-03 5.2046E-03 -1.8401E-03 2.2349E-03 5.3044E-04 S12 -1.0279E-02 2.9703E-01 -1.0709E-01 1.8305E-02 -4.0626E-03 1.9694E-03 -3.5146E-03 2.1706E-03 4.6890E-04 S13 -2.5188E+00 -3.1623E-01 5.4753E-02 1.3767E-02 2.1149E-02 7.1756E-03 8.4195E-03 5.1344E-03 9.7104E-04 S14 -1.1752E+00 -2.2209E-01 3.1892E-01 -1.8034E-01 5.8035E-02 1.9846E-03 1.2239E-02 -1.8516E-02 -6.3086E-03 S15 -5.6312E+00 1.5188E+00 -4.3006E-01 1.2084E-01 -1.2961E-03 -2.5863E-02 1.1429E-02 -1.2282E-03 -1.1630E-04 S16 -1.2869E+01 2.9173E+00 -1.3289E+00 4.4711E-01 -2.2549E-01 5.4869E-02 -2.5366E-02 1.2050E-04 -1.2793E-03

[0135] Table 12

[0136] Figure 12A shows the axial chromatic aberration curve of the optical imaging lens 600 in Embodiment 6, which represents the deviation of the convergence points of light rays with different wavelengths after passing through the optical imaging lens 600. Figure 12B shows the astigmatism curve of the optical imaging lens 600 in Embodiment 6, which represents the meridional image plane curvature and sagittal image plane curvature corresponding to different image heights. Figure 12C shows the distortion curve of the optical imaging lens 600 in Embodiment 6, which represents the distortion magnitude values corresponding to different image heights. Figure 12D shows the longitudinal chromatic aberration curve of the optical imaging lens 600 in Embodiment 6, which represents the deviation of different image heights of light rays on the imaging surface after passing through the lens. According to Figures 12A to 12D it can be seen that the optical imaging lens 600 given in Embodiment 6 can achieve good imaging quality.

[0137] In summary, the conditions in Embodiments 1 to 6 satisfy the relationships shown in Table 13.

[0138] Conditional / Example 1 2 3 4 5 6 f8 / R15 -2.56 -2.04 -2.37 -3.83 -1.99 -4.34 R12 / f6 0.28 0.30 0.33 0.59 0.33 0.35 CT4 / T12 3.99 6.11 6.62 7.89 8.06 6.33 TTL / ImgH 1.20 1.17 1.21 1.16 1.13 0.99 tan(Semi - FOV)×ImgH 7.67 8.65 7.25 6.67 8.14 7.63 ET8 / CT8 1.41 1.03 1.57 3.24 1.31 2.43 (CT2 + CT7) / (CT3 + CT6) 1.26 2.00 1.37 1.82 2.08 2.01 ET5 / CT5 0.90 0.86 0.72 0.48 0.73 0.77 f2 / (R3 - R4) -7.30 -11.23 -7.51 -4.05 -5.53 -6.48 (R11 + R12) / (R11 - R12) -4.83 -4.83 -4.53 -3.05 -4.54 -4.34 (CT5 + CT6) / T56 1.64 0.82 1.06 1.32 1.11 1.61 f6 / R11 + f7 / R13 7.36 6.80 6.68 5.17 6.63 6.44 DT81 / (DT82 - DT72) 2.22 3.46 2.86 2.24 3.72 1.88 ∑CT / BFL 3.28 2.66 2.69 3.20 2.67 2.88

[0139] Table 13

[0140] The present application also provides an imaging device, and its electronic photosensitive element may be a charge-coupled device (CCD) or a complementary metal-oxide-semiconductor device (CMOS). The imaging device may be an independent imaging device such as a digital camera, or may be an imaging module integrated on a mobile electronic device such as a mobile phone. The imaging device is equipped with the optical imaging lens described above.

[0141] The above description is only the preferred embodiment of the present application and the explanation of the applied technical principles. Those skilled in the art should understand that the scope of the invention involved in the present application is not limited to the technical solution formed by the specific combination of the above technical features, and should also cover other technical solutions formed by any combination of the above technical features or their equivalent features without departing from the inventive concept. For example, the technical solution formed by the mutual replacement of the above features and the technical features (but not limited to) with similar functions disclosed in the present application.

Claims

1. An optical imaging lens, characterized in that, In order from the object side to the image side along the optical axis, it includes: A first lens with positive refractive power, whose object side is convex and image side is concave; A second lens with negative refractive power, whose object side is convex and image side is concave; A third lens with negative refractive power, whose object side is convex and image side is concave; A fourth lens with positive refractive power, whose image side is convex; A fifth lens with negative refractive power; A sixth lens with negative refractive power, whose object side is concave and image side is convex; A seventh lens with positive refractive power, whose object side is convex; and An eighth lens with negative refractive power, whose object side is convex and image side is concave; The number of lenses with refractive power in the optical imaging lens is eight. Among them, the effective focal length f8 of the eighth lens and the curvature radius R15 of the object side of the eighth lens satisfy: -4.34 ≤ f8 / R15 ≤ -1.

99. The effective focal length f6 of the sixth lens and the curvature radius R12 of the image side of the sixth lens satisfy: 0.28 ≤ R12 / f6 ≤ 0.

59. The central thickness CT4 of the fourth lens on the optical axis and the air gap T12 between the first lens and the second lens on the optical axis satisfy: 3.99 ≤ CT4 / T12 ≤ 8.

06.

2. The optical imaging lens according to claim 1, characterized in that, The on-axis distance TTL from the object side of the first lens to the imaging surface of the optical imaging lens and half of the diagonal length ImgH of the effective pixel region on the imaging surface of the optical imaging lens satisfy: 0.95 < TTL / ImgH < 1.

25.

3. The optical imaging lens according to claim 1, wherein Half of the maximum field of view Semi-FOV of the optical imaging lens and half of the diagonal length ImgH of the effective pixel region on the imaging surface of the optical imaging lens satisfy: 6.67mm ≤ tan(Semi-FOV) × ImgH ≤ 8.65mm.

4. The optical imaging lens according to claim 1, wherein The edge thickness ET8 at the maximum effective aperture of the eighth lens and the central thickness CT8 of the eighth lens on the optical axis satisfy: 1.03 ≤ ET8 / CT8 ≤ 3.

24.

5. The optical imaging lens according to claim 1, characterized in that, The central thickness CT2 of the second lens on the optical axis, the central thickness CT3 of the third lens on the optical axis, the central thickness CT6 of the sixth lens on the optical axis and the central thickness CT7 of the seventh lens on the optical axis satisfy: 1.26 ≤ (CT2 + CT7) / (CT3 + CT6) ≤ 2.

08.

6. The optical imaging lens according to claim 1, wherein The edge thickness ET5 at the maximum effective aperture of the fifth lens and the central thickness CT5 of the fifth lens on the optical axis satisfy: 0.48 ≤ ET5 / CT5 ≤ 0.

90.

7. The optical imaging lens according to claim 1, wherein The effective focal length f2 of the second lens, 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: -11.23 ≤ f2 / (R3 - R4) ≤ -4.

05.

8. The optical imaging lens according to claim 1, characterized in that, 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: -4.83 ≤ (R11 + R12) / (R11 - R12) ≤ -3.

05.

9. The optical imaging lens according to claim 1, characterized in that, The central thickness CT5 of the fifth lens on the optical axis, the central thickness CT6 of the sixth lens on the optical axis, and the air gap T56 between the fifth lens and the sixth lens on the optical axis satisfy: 0.82 ≤ (CT5 + CT6) / T56 ≤ 1.

64.

10. The optical imaging lens according to claim 1, characterized in that, The effective focal length f6 of the sixth lens, the effective focal length f7 of the seventh lens, the radius of curvature R11 of the object side of the sixth lens, and the radius of curvature R13 of the object side of the seventh lens satisfy: 5.17 ≤ f6 / R11 + f7 / R13 ≤ 7.

36.

11. The optical imaging lens according to claim 1, wherein The effective semi-aperture DT72 of the image side of the seventh lens, the effective semi-aperture DT81 of the object side of the eighth lens, and the effective semi-aperture DT82 of the image side of the eighth lens satisfy: 1.88 ≤ DT81 / (DT82 - DT72) ≤ 3.

72.

12. The optical imaging lens according to claim 1, wherein The minimum value Nmin of the refractive indices of all the lenses from the first lens to the eighth lens satisfies: Nmin > 1.5, and the minimum value Vmin of the Abbe numbers of all the lenses from the first lens to the eighth lens satisfies: Vmin < 20.

13. The optical imaging lens according to claim 1, characterized in that, The on-axis distance BFL from the image side of the eighth lens to the imaging surface of the optical imaging lens and the sum ∑CT of the central thicknesses of all the lenses from the first lens to the eighth lens on the optical axis satisfy: 2.66 ≤ ∑CT / BFL ≤ 3.28.

Images