Imaging lens

Abstract

The present application discloses an imaging lens, which sequentially includes, from the object side to the image side along the optical axis: a first lens made of glass; a second lens; a third lens with a positive optical power; a fourth lens with a negative optical power; a fifth lens with a positive optical power; a sixth lens with a convex object side surface and a concave image side surface; a seventh lens with a convex image side surface; an eighth lens; wherein, the number of lenses with optical power in the imaging lens is eight, and the imaging lens satisfies: TTL / ImgH≤1.29, and 0.9<CT3 / CT4<3; where TTL is the distance along the optical axis from the object side surface of the first lens to the imaging surface of the imaging lens, ImgH is half of the diagonal length of the effective pixel area on the imaging surface, CT3 is the central thickness of the third lens on the optical axis, and CT4 is the central thickness of the fourth lens on the optical axis.

Description

Technical Field

[0001] The present application relates to the field of optical elements, and specifically, to an imaging lens. Background Art

[0002] With the progress of science and the development of society, people have higher requirements for the quality of life products. For example, for electronic devices with certain shooting functions, people hope that the imaging lenses carried by them have excellent shooting performance while also hoping that the size of the electronic devices can be as small as possible to meet the requirements of convenient carrying.

[0003] Telephoto lenses are widely used in the above-mentioned electronic devices with shooting functions because they can capture local details of objects at relatively long distances and obtain images of the photographed objects at relatively short distances. However, how to balance the imaging performance (such as a large image plane) of telephoto lenses and the system size has become an urgent problem to be solved currently.

[0004] It should be understood that this background art section aims to partially provide useful background for understanding the technology. However, these contents are not necessarily known or understood by those skilled in the art before the filing date of the present application. Summary of the Invention

[0005] The present application provides an imaging lens, which sequentially includes, from the object side to the image side along the optical axis: a first lens made of glass; a second lens; a third lens with a positive optical power; a fourth lens with a negative optical power; a fifth lens with a positive optical power; a sixth lens with a convex object side and a concave image side; a seventh lens with a convex image side; an eighth lens; wherein, the number of lenses with optical power in the imaging lens is eight, and the imaging lens satisfies: TTL / ImgH ≤ 1.29, and 0.9 < CT3 / CT4 < 3; where TTL is the distance along the optical axis from the object side of the first lens to the imaging plane of the imaging lens, ImgH is half of the diagonal length of the effective pixel region on the imaging plane, CT3 is the central thickness of the third lens on the optical axis, and CT4 is the central thickness of the fourth lens on the optical axis.

[0006] In an embodiment of the present application, the imaging lens satisfies: 0.5 < f123 / (f1 + f2 + f3) < 1.5, where f1 is the effective focal length of the first lens, f2 is the effective focal length of the second lens, f3 is the effective focal length of the third lens, and f123 is the combined focal length of the first lens, the second lens, and the third lens.

[0007] In an embodiment of the present application, the imaging lens satisfies: 6 < (R11 + R12) / (R11 - R12) < 18, where R11 is the radius of curvature of the object side surface of the sixth lens, and R12 is the radius of curvature of the image side surface of the sixth lens.

[0008] In an embodiment of the present application, the imaging lens satisfies: 0.7 < T56 / T34 < 1.5, where T34 is the air gap between the third lens and the fourth lens along the optical axis, and T56 is the air gap between the fifth lens and the sixth lens along the optical axis.

[0009] In an embodiment of the present application, the imaging lens satisfies: 0.8 < CT5 / CT8 < 3, where CT5 is the central thickness of the fifth lens on the optical axis, and CT8 is the central thickness of the eighth lens on the optical axis.

[0010] In an embodiment of the present application, the imaging lens satisfies: Semi-FOV > 42°, where Semi-FOV is half of the maximum field angle of the imaging lens.

[0011] In an embodiment of the present application, the imaging lens satisfies: ImgH > 5.5 mm, where ImgH is half of the diagonal length of the effective pixel area on the imaging surface.

[0012] In an embodiment of the present application, the imaging lens satisfies: 0 < (CT7 + CT8) / T78 < 1.3, where CT7 is the central thickness of the seventh lens on the optical axis, CT8 is the central thickness of the eighth lens on the optical axis, and T78 is the air gap between the seventh lens and the eighth lens along the optical axis.

[0013] In an embodiment of the present application, the material of any one of the second lens to the eighth lens is plastic, where the refractive index of any one of the lenses is greater than 1.5.

[0014] In an embodiment of the present application, the imaging lens satisfies: Vg > 30.0, where Vg is the dispersion coefficient of the first lens.

[0015] In an embodiment of the present application, the imaging lens satisfies: 5 < 1 / (Npmax - Ng) < 35, where Npmax is the maximum value of the refractive indices of each of the second lens to the eighth lens, and Ng is the refractive index of the first lens.

[0016] In an embodiment of the present application, the imaging lens satisfies: 1.5 < T23 / T12 < 4.5, where T12 is the air gap between the first lens and the second lens along the optical axis, and T23 is the air gap between the second lens and the third lens along the optical axis.

[0017] In an embodiment of the present application, the imaging lens satisfies: -1.5 < R16 / R15 < 0, where R15 is the radius of curvature of the object side surface of the eighth lens, and R16 is the radius of curvature of the image side surface of the eighth lens.

[0018] In an embodiment of the present application, the imaging lens satisfies: 0.2 < (CT5 + CT6) / (T56 + T67) < 1.3, where CT5 is the central thickness of the fifth lens on the optical axis, CT6 is the central thickness of the sixth lens on the optical axis, T56 is the air gap between the fifth lens and the sixth lens along the optical axis, and T67 is the air gap between the sixth lens and the seventh lens along the optical axis.

[0019] In an embodiment of the present application, the imaging lens satisfies: 1 < ET8 / ET1 < 5.5, where ET1 is the edge thickness at the maximum effective diameter of the first lens, and ET8 is the edge thickness at the maximum effective diameter of the eighth lens.

[0020] In an embodiment of the present application, the imaging lens satisfies: -8 < (f6 + f7) / f67 < -2, where f6 is the effective focal length of the sixth lens, f7 is the effective focal length of the seventh lens, and f67 is the combined focal length of the sixth lens and the seventh lens.

[0021] In an embodiment of the present application, the imaging lens satisfies: f / f4 < 0, where f is the total effective focal length of the imaging lens, and f4 is the effective focal length of the fourth lens.

[0022] The imaging lens of the present application uses multiple (e.g., eight) lenses. By reasonably setting the ratio of the distance from the object side surface of the first lens to the imaging surface along the optical axis to half of the diagonal length of the effective pixel area on the imaging surface, it is possible to achieve a large image surface while making the imaging lens miniaturized; in addition, by reasonably setting the ratio of the central thickness of the third lens on the optical axis to the central thickness of the fourth lens on the optical axis, the lens is easy to be injection molded, improving the processability of the imaging lens and ensuring good imaging quality. BRIEF DESCRIPTION OF THE DRAWINGS

[0023] By reading the detailed description of the non-restrictive embodiments made with reference to the following drawings, other features, objects, and advantages of the present application will become more obvious. In the drawings:

[0024] Figure 1 1 shows a schematic structural diagram of an imaging lens according to Example 1 of the present application;

[0025] Figures 2A to 2D axial chromatic aberration curve, astigmatism curve, distortion curve, and lateral chromatic aberration curve of the imaging lens according to Example 1 of the present application are respectively shown;

[0026] Figure 3 1 shows a schematic structural diagram of an imaging lens according to Example 2 of the present application;

[0027] Figures 4A to 4D axial chromatic aberration curve, astigmatism curve, distortion curve, and lateral chromatic aberration curve of the imaging lens according to Example 2 of the present application are respectively shown;

[0028] Figure 5 1 shows a schematic structural diagram of an imaging lens according to Example 3 of the present application;

[0029] 6A to 6D axial chromatic aberration curve, astigmatism curve, distortion curve, and lateral chromatic aberration curve of the imaging lens according to Example 3 of the present application are respectively shown;

[0030] Figure 7 1 shows a schematic structural diagram of an imaging lens according to Example 4 of the present application;

[0031] Figures 8A to 8D axial chromatic aberration curve, astigmatism curve, distortion curve, and lateral chromatic aberration curve of the imaging lens according to Example 4 of the present application are respectively shown;

[0032] Figure 9 1 shows a schematic structural diagram of an imaging lens according to Example 5 of the present application;

[0033] 10A to 10D axial chromatic aberration curve, astigmatism curve, distortion curve, and lateral chromatic aberration curve of the imaging lens according to Example 5 of the present application are respectively shown;

[0034] Figure 11 shows a schematic structural diagram of an imaging lens according to Example 6 of the present application; and

[0035] 12A to 12D axial chromatic aberration curve, astigmatism curve, distortion curve, and lateral chromatic aberration curve of the imaging lens according to Example 6 of the present application are respectively shown; DETAILED DESCRIPTION

[0036] For a better understanding of the present application, various aspects of the present application will be described in more detail with reference to the accompanying drawings. It should be understood that these detailed descriptions are merely descriptions of exemplary embodiments of the present application and are not intended to limit the scope of the present application in any way. Throughout the specification, the same reference numerals refer to the same elements. The expression "and / or" includes any and all combinations of one or more of the associated listed items.

[0037] It should be noted that in this specification, the terms "first," "second," "third," etc., are used solely to distinguish one feature from another and do not limit the features. Thus, the first lens discussed below could also be referred to as the second lens or the third lens without departing from the teachings of this application.

[0038] In the drawings, the thickness, size, and shape of the lenses are slightly exaggerated for ease of illustration. Specifically, the shapes of the spherical and aspherical surfaces shown in the drawings are provided by way of example. That is, the shapes of the spherical and aspherical surfaces are not limited to those shown in the drawings. The drawings are for illustration only and are not drawn strictly to scale.

[0039] In this article, the paraxial region refers to the area near the optical axis. If a lens surface is convex and the location of the convex surface is undefined, it means that the lens surface is convex at least in the paraxial region. If a lens surface is concave and the location of the concave surface is undefined, it means that the lens surface is concave at least in the paraxial region. The surface of each lens closest to the subject is called the object-side surface of the lens, and the surface of each lens closest to the imaging plane is called the image-side surface of the lens.

[0040] It should also be understood that the terms "comprises," "including," "having," "includes," and / or "comprising," when used in this specification, indicate the presence of the stated features, elements, and / or components, but do not preclude the presence or addition of one or more other features, elements, components, and / or combinations thereof. In addition, when expressions such as "at least one of..." appear after a list of listed features, they modify the entire list of features rather than modifying the individual elements in the list. In addition, when describing embodiments of the present application, "may" is used to mean "one or more embodiments of the present application." And, the term "exemplary" is intended to refer to an example or illustration.

[0041] Unless otherwise defined, all terms used herein (including technical and scientific terms) have the same meaning as commonly understood by one of ordinary skill in the art to which this application belongs. It should also be understood that terms (such as those defined in commonly used dictionaries) should be interpreted as having a meaning consistent with their meaning in the context of the relevant technology and will not be interpreted in an idealized or overly formal sense unless expressly defined as such herein.

[0042] It should be noted that, without conflict, the embodiments and features in the embodiments of the present application can be combined with each other. The present application will be described in detail below with reference to the drawings and in combination with the embodiments.

[0043] The features, principles and other aspects of the present application will be described in detail below.

[0044] The imaging lens according to an exemplary embodiment of the present application may include, in order from the object side to the image side along the optical axis, a first lens, a second lens, a third lens, a fourth lens, a fifth lens, a sixth lens, a seventh lens and an eighth lens, each having a focal power.

[0045] In the exemplary embodiment, the first lens may have a positive focal power, its object side surface may be convex, and its image side surface may be concave; the second lens may have a negative focal power, its object side surface is convex, and its image side surface is concave; the third lens may have a positive focal power, its object side surface may be convex, and its image side surface may be concave; the fourth lens may have a negative focal power, its object side surface may be concave, and its image side surface may be concave or convex; the fifth lens may have a positive focal power, its object side surface may be concave or convex, and its image side surface may be convex; the sixth lens may have a negative focal power, its object side surface may be convex, and its image side surface may be concave; the seventh lens may have a positive focal power, its object side surface may be convex, and its image side surface may be convex; the eighth lens may have a negative focal power, its object side surface may be concave, and its image side surface may be concave. By reasonably distributing the surface types and focal powers of the respective lenses of the imaging lens, the imaging effect can be effectively improved. In addition, by reasonably controlling the surface types of each lens, the path of light in the optical system can be further adjusted, effectively improving the resolution of the imaging lens and balancing the aberration of the imaging lens.

[0046] In the exemplary embodiment, the imaging lens satisfies: TTL / ImgH ≤ 1.29, and 0.9 < CT3 / CT4 < 3; where, TTL is the distance along the optical axis from the object side surface of the first lens to the imaging surface, ImgH is half of the diagonal length of the effective pixel region on the imaging surface, CT3 is the central thickness of the third lens on the optical axis, and CT4 is the central thickness of the fourth lens on the optical axis. Further, the imaging lens satisfies: 0.5 < TTL / ImgH ≤ 1.29, and 1.5 < CT3 / CT4 < 2.5. By reasonably setting the ratio of the distance along the optical axis from the object side surface of the first lens to the imaging surface to half of the diagonal length of the effective pixel region on the imaging surface, the imaging lens can be miniaturized while achieving a large image surface; in addition, by reasonably setting the ratio of the central thickness of the third lens on the optical axis to the central thickness of the fourth lens on the optical axis, the lens is easy to be injection molded, improving the processability of the imaging lens and ensuring good imaging quality.

[0047] In an exemplary embodiment, the imaging lens satisfies: 0.5 < f123 / (f1 + f2 + f3) < 1.5, where f1 is the effective focal length of the first lens, f2 is the effective focal length of the second lens, f3 is the effective focal length of the third lens, and f123 is the combined focal length of the first lens, the second lens, and the third lens. Further, the imaging lens satisfies: 0.5 < f123 / (f1 + f2 + f3) < 1.0. By reasonably allocating the ratio of the combined focal length of the first lens, the second lens, and the third lens to the effective focal lengths of these three lenses respectively, the aberration of the lens can be effectively improved, and the field angle of the lens can be increased.

[0048] In an exemplary embodiment, the imaging lens satisfies: 6 < (R11 + R12) / (R11 - R12) < 18, where R11 is the radius of curvature of the object side surface of the sixth lens, and R12 is the radius of curvature of the image side surface of the sixth lens. Further, the imaging lens satisfies: 7 < (R11 + R12) / (R11 - R12) < 16. By reasonably controlling the ratio of the sum of the radius of curvature of the object side surface and the image side surface of the sixth lens to the difference between the radius of curvature of the object side surface and the image side surface of this lens, the field curvature and distortion of the imaging lens can be improved, and at the same time, the processing difficulty of the sixth lens can be controlled.

[0049] In an exemplary embodiment, the imaging lens satisfies: 0.7 < T56 / T34 < 1.5, where T34 is the air gap between the third lens and the fourth lens along the optical axis, and T56 is the air gap between the fifth lens and the sixth lens along the optical axis. Further, the imaging lens satisfies: 1.0 < T56 / T34 < 1.4. By reasonably controlling the ratio of the air gap between the fifth lens and the sixth lens along the optical axis to the air gap between the third lens and the fourth lens along the optical axis, the assembly difficulty of the lens can be reduced.

[0050] In an exemplary embodiment, the imaging lens satisfies: 0.8 < CT5 / CT8 < 3, where CT5 is the central thickness of the fifth lens on the optical axis, and CT8 is the central thickness of the eighth lens on the optical axis. Further, the imaging lens satisfies: 1.0 < CT5 / CT8 < 2.5. By reasonably controlling the ratio of the central thickness of the fifth lens on the optical axis to the central thickness of the eighth lens on the optical axis, it is beneficial to improve the lens assembly stability of the imaging lens and the consistency of mass production, and is beneficial to improving the production yield of the imaging lens.

[0051] In an exemplary embodiment, the imaging lens satisfies: Semi-FOV > 42°, where Semi-FOV is half of the maximum field angle of the imaging lens. Further, the imaging lens satisfies: 42° <semi-fov>50°. Meeting the requirement of Semi - FOV > 42°, the imaging lens can have a broader imaging field of view.

[0052] In an exemplary embodiment, the imaging lens meets the condition: ImgH > 5.5 mm, where ImgH is half of the diagonal length of the effective pixel area on the imaging surface. Further, the imaging lens meets the condition: 6.5 mm < ImgH < 9.0 mm. Meeting the requirement of ImgH > 5.5 mm, the imaging lens can achieve the imaging effect of a large image surface.

[0053] In an exemplary embodiment, the imaging lens meets the condition: TTL > 7.5 mm, where TTL is the distance along the optical axis from the object side surface of the first lens to the imaging surface. Further, the imaging lens meets the condition: 7.5 mm < TTL < 9.0 mm. By reasonably controlling the optical length of the imaging lens, the imaging lens has the characteristic of miniaturization.

[0054] In an exemplary embodiment, the imaging lens meets the condition: 0 < (CT7 + CT8) / T78 < 1.3, where CT7 is the central thickness of the seventh lens on the optical axis, CT8 is the central thickness of the eighth lens on the optical axis, and T78 is the air gap between the seventh lens and the eighth lens along the optical axis. Further, the imaging lens meets the condition: 0.5 < (CT7 + CT8) / T78 < 1.0. By reasonably controlling the ratio of the sum of the central thicknesses of the seventh lens and the eighth lens on the optical axis to the air gap between the seventh lens and the eighth lens along the optical axis, the rear end size of the imaging lens can be effectively reduced, ensuring the miniaturization of the lens and being beneficial to the assembly of the lens.

[0055] In an exemplary embodiment, the material of any one of the second lens to the eighth lens is plastic, and the refractive index of any lens with plastic material is greater than 1.5. Meeting the above conditions can balance the chromatic aberration of the lens and correct the lens aberration on the premise of controlling the cost, thereby improving the imaging quality of the lens.

[0056] In an exemplary embodiment, the imaging lens meets the condition: Vg > 30.0, where Vg is the dispersion coefficient of the first lens. Further, the imaging lens meets the condition: 30.0 < Vg < 65.0. By restricting the dispersion coefficient of the lens with glass material in the imaging lens, the dispersion ability of the glass lens can be reasonably distributed, making the chromatic aberration generated by the plastic lens balance with that of the glass lens, and the aberration of the lens is fully corrected, thereby improving the imaging quality.

[0057] In an exemplary embodiment, the imaging lens satisfies: 5 < 1 / (Npmax - Ng) < 35, where Npmax is the maximum value of the refractive indices of each of the second lens to the eighth lens, and Ng is the refractive index of the first lens. Further, the imaging lens satisfies: 7 < 1 / (Npmax - Ngmax) < 28. By reasonably allocating the relationship between the refractive index of the lens with the maximum refractive index among the plastic lenses and the refractive index of the lens with the minimum refractive index among the glass lenses, the chromatic dispersion ability of the lens can be reasonably allocated, and the axial chromatic aberration and lateral chromatic aberration can be better corrected; at the same time, it is beneficial to the molding process of the plastic lens and the glass lens, thereby improving the production yield of the lens.

[0058] In an exemplary embodiment, the imaging lens satisfies: 1.5 < T23 / T12 < 4.5, where T12 is the air gap between the first lens and the second lens along the optical axis, and T23 is the air gap between the second lens and the third lens along the optical axis. Further, the imaging lens satisfies: 1.8 < T23 / T12 < 4.0. By reasonably controlling the ratio of the air gap between the second lens and the third lens along the optical axis to the air gap between the first lens and the second lens along the optical axis, interference at the edge of the lens can be avoided, and the assembly difficulty of the lens can be reduced.

[0059] In an exemplary embodiment, the imaging lens satisfies: -1.5 < R16 / R15 < 0, where R15 is the curvature radius of the object side of the eighth lens, and R16 is the curvature radius of the image side of the eighth lens. Further, the imaging lens satisfies: -1.2 < R16 / R15 < -0.4. By reasonably controlling the ratio of the curvature radius of the image side of the eighth lens to the curvature radius of the object side of the eighth lens, it is beneficial to ensure that the eighth lens has an appropriate optical power, while reducing the angle between the chief ray and the optical axis when it enters the image plane, and improving the illuminance of the image plane.

[0060] In an exemplary embodiment, the imaging lens satisfies: 0.2 < (CT5 + CT6) / (T56 + T67) < 1.3, where CT5 is the central thickness of the fifth lens on the optical axis, CT6 is the central thickness of the sixth lens on the optical axis, T56 is the air gap between the fifth lens and the sixth lens along the optical axis, and T67 is the air gap between the sixth lens and the seventh lens along the optical axis. Further, the imaging lens satisfies: 0.4 < (CT� + CT6) / (T56 + T67) < 1.0. By reasonably allocating the ratio relationship between the sum of the central thicknesses of the fifth lens and the sixth lens on the optical axis and the sum of the air gaps between the fifth lens and the sixth lens and between the sixth lens and the seventh lens along the optical axis, the size of the lens can be reasonably arranged, so as to improve the resolution while reducing the thickness of the lens.

[0061] In an exemplary embodiment, the imaging lens satisfies: 1 < ET8 / ET1 < 5.5, where ET1 is the edge thickness at the maximum effective diameter of the first lens, and ET8 is the edge thickness at the maximum effective diameter of the eighth lens. Further, the imaging lens satisfies: 1.5 < ET8 / ET1 < 4.5. By reasonably controlling the ratio of the edge thickness at the maximum effective diameter of the first lens to the edge thickness at the maximum effective diameter of the eighth lens, the assembly difficulty of the lens can be reduced and the degree of light deflection can be controlled.

[0062] In an exemplary embodiment, the imaging lens satisfies: -8 < (f6 + f7) / f67 < -2, where f6 is the effective focal length of the sixth lens, f7 is the effective focal length of the seventh lens, and f67 is the combined focal length of the sixth lens and the seventh lens. Further, the imaging lens satisfies: -7.5 < (f6 + f7) / f67 < -2.5. By reasonably controlling the ratio of the sum of the effective focal lengths of the sixth lens and the seventh lens to the combined focal length of the sixth lens and the seventh lens, it is beneficial to balance the aberration of the lens and improve the resolution of the lens.

[0063] In an exemplary embodiment, the imaging lens satisfies: f / f4 < 0, where f is the total effective focal length of the imaging lens, and f4 is the effective focal length of the fourth lens. Further, the imaging lens satisfies: -0.2 < f / f4 < 0. By reasonably controlling the ratio of the total effective focal length of the lens to the effective focal length of the fourth lens, it is possible to avoid excessive light deflection and at the same time enhance the ability of the lens to correct field curvature.

[0064] In an exemplary embodiment, the imaging lens according to the present application may further include a filter for correcting color deviation and / or a protective glass for protecting the photosensitive element located on the imaging surface.

[0065] In an embodiment of the present application, at least one of the lens surfaces of each of the first lens to the eighth lens is an aspherical lens 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 improving 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. Optionally, the object side and the image side of each of the first lens to the eighth lens are aspherical lens surfaces.

[0066] However, those skilled in the art will appreciate that the number of lenses comprising an imaging lens can be varied to achieve the various results and advantages described herein without departing from the claimed technical solutions. For example, while eight lenses are described as an example in the embodiments, the imaging lens is not limited to eight lenses. If desired, the imaging lens may also include other numbers of lenses.

[0067] Specific embodiments of imaging lenses applicable to the above-mentioned embodiments will be further described below with reference to the accompanying drawings.

[0068] Example 1

[0069] The following reference Figures 1 to 2D The imaging lens according to embodiment 1 of the present application is described. Figure 1 As shown, the imaging lens includes, from the object side to the image side along the optical axis, an aperture STO, 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, an eighth lens E8, a filter E9 and an imaging surface S19.

[0070] The first lens E1 has positive focal power, with its object-side surface S1 being convex and its image-side surface S2 being concave. The second lens E2 has negative focal power, with its object-side surface S3 being convex and its image-side surface S4 being concave. The third lens E3 has positive focal power, with its object-side surface S5 being convex and its image-side surface S6 being concave. The fourth lens E4 has negative focal power, with its object-side surface S7 being concave and its image-side surface S8 being concave. The fifth lens E5 has positive focal power, with its object-side surface S9 being convex and its image-side surface S10 being convex. The sixth lens E6 has negative focal power, with its object-side surface S11 being convex and its image-side surface S12 being concave. The seventh lens E7 has positive focal power, with its object-side surface S13 being convex and its image-side surface S14 being convex. The eighth lens E8 has negative focal power, with its object-side surface S15 being concave and its image-side surface S16 being concave. The optical filter E9 has an object-side surface S17 and an image-side surface S18. Light from an object passes through the surfaces S1 to S18 in sequence and is finally imaged on the imaging surface S19 .

[0071] Table 1 shows basic parameters of the imaging lens of Example 1, wherein the units of curvature radius, thickness / distance, and focal length are all millimeters (mm).

[0072]

[0073] Table 1

[0074] In this embodiment, the total effective focal length f of the imaging lens is 7.77 mm, the distance TTL along the optical axis from the object-side surface S1 of the first lens element E1 to the imaging surface S19 is 8.90 mm, half the diagonal length of the effective pixel area on the imaging surface S19 ImgH is 8.42 mm, half the maximum field of view (Semi-FOV) of the imaging lens is 47.0°, and the aperture value FNO of the imaging lens is 1.90.

[0075] In this embodiment, the aspheric surfaces included in the object-side and image-side surfaces of the first lens E1 to the eighth lens E8 are The following aspheric formulas can be used for definition, but are not limited to:

[0076] (1)

[0077] in, is the distance vector 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 radius of curvature R in Table 1 above); k is the conic coefficient; Ai is the correction coefficient for the i-th order of the aspheric surface. Table 2 below lists the higher-order coefficients A4, A6, A8, A10, A12, A14, A16, A18, A20, A22, A24, A26, A28, and A30 that can be used for each of the aspheric mirrors S1 to S16 in Example 1.

[0078]

[0079] Table 2

[0080] Figure 2A The axial chromatic aberration curve of the imaging lens of Example 1 is shown, which indicates the deviation of the convergent focus of light of different wavelengths after passing through the imaging lens. Figure 2B The astigmatism curve of the imaging lens of Example 1 is shown, which indicates meridional field curvature and sagittal field curvature. Figure 2C The distortion curve of the imaging lens of Example 1 is shown, which represents the distortion magnitude values ​​corresponding to different image heights. Figure 2D The chromatic aberration curve of the imaging lens of Example 1 is shown, which represents the deviation of different image heights on the imaging surface after the light passes through the lens. Figures 2A to 2D It can be seen that the imaging lens provided in Example 1 can achieve good imaging quality.

[0081] Example 2

[0082] The following reference Figures 3 to 4D The imaging lens according to embodiment 2 of the present application is described. Figure 3 As shown, the imaging lens includes, from the object side to the image side along the optical axis, an aperture STO, 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, an eighth lens E8, a filter E9 and an imaging surface S19.

[0083] The first lens E1 has positive focal power, with its object-side surface S1 being convex and its image-side surface S2 being concave. The second lens E2 has negative focal power, with its object-side surface S3 being convex and its image-side surface S4 being concave. The third lens E3 has positive focal power, with its object-side surface S5 being convex and its image-side surface S6 being concave. The fourth lens E4 has negative focal power, with its object-side surface S7 being concave and its image-side surface S8 being convex. The fifth lens E5 has positive focal power, with its object-side surface S9 being convex and its image-side surface S10 being convex. The sixth lens E6 has negative focal power, with its object-side surface S11 being convex and its image-side surface S12 being concave. The seventh lens E7 has positive focal power, with its object-side surface S13 being convex and its image-side surface S14 being convex. The eighth lens E8 has negative focal power, with its object-side surface S15 being concave and its image-side surface S16 being concave. The optical filter E9 has an object-side surface S17 and an image-side surface S18. Light from an object passes through the surfaces S1 to S18 in sequence and is finally imaged on the imaging surface S19 .

[0084] Table 3 shows the basic parameters of the imaging lens of Example 2, where the units of curvature radius, thickness / distance, and focal length are all millimeters (mm).

[0085]

[0086] Table 3

[0087] In this embodiment, the total effective focal length f of the imaging lens is 7.66 mm, the distance TTL along the optical axis from the object-side surface S1 of the first lens element E1 to the imaging surface S19 is 8.93 mm, half the diagonal length of the effective pixel area on the imaging surface S19 ImgH is 8.42 mm, half the maximum field of view (Semi-FOV) of the imaging lens is 47.0°, and the aperture value FNO of the imaging lens is 1.90.

[0088] Table 4 shows the high-order coefficients A4, A6, A8, A10, A12, A14, A16, A18, A20, A22, A24, A26, A28 and A30 of each mirror surface that can be used in the aspheric surfaces S1 to S16 in Example 2, wherein the surface shape of each aspheric surface can be defined by formula (1) given in the above-mentioned Example 1.

[0089]

[0090] Table 4

[0091] Figure 4A The axial chromatic aberration curve of the imaging lens of Example 2 is shown, which indicates the deviation of the convergent focus of light of different wavelengths after passing through the imaging lens. Figure 4B The astigmatism curve of the imaging lens of Example 2 is shown, which indicates meridional field curvature and sagittal field curvature. Figure 4C The distortion curve of the imaging lens of Example 2 is shown, which represents the distortion magnitude values ​​corresponding to different image heights. Figure 4D The chromatic aberration curve of the imaging lens of Example 2 is shown, which represents the deviation of different image heights on the imaging surface after the light passes through the lens. Figures 4A to 4D It can be seen that the imaging lens provided in Example 2 can achieve good imaging quality.

[0092] Example 3

[0093] The following reference Figures 5 to 6D The imaging lens according to embodiment 3 of the present application is described. Figure 5 As shown, the imaging lens includes, from the object side to the image side along the optical axis, an aperture STO, 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, an eighth lens E8, a filter E9 and an imaging surface S19.

[0094] The first lens E1 has positive focal power, with its object-side surface S1 being convex and its image-side surface S2 being concave. The second lens E2 has negative focal power, with its object-side surface S3 being convex and its image-side surface S4 being concave. The third lens E3 has positive focal power, with its object-side surface S5 being convex and its image-side surface S6 being concave. The fourth lens E4 has negative focal power, with its object-side surface S7 being concave and its image-side surface S8 being convex. The fifth lens E5 has positive focal power, with its object-side surface S9 being concave and its image-side surface S10 being convex. The sixth lens E6 has negative focal power, with its object-side surface S11 being convex and its image-side surface S12 being concave. The seventh lens E7 has positive focal power, with its object-side surface S13 being convex and its image-side surface S14 being convex. The eighth lens E8 has negative focal power, with its object-side surface S15 being concave and its image-side surface S16 being concave. The optical filter E9 has an object-side surface S17 and an image-side surface S18. Light from an object passes through the surfaces S1 to S18 in sequence and is finally imaged on the imaging surface S19 .

[0095] Table 5 shows the basic parameters of the imaging lens of Example 3, where the units of curvature radius, thickness / distance, and focal length are all millimeters (mm).

[0096]

[0097] Table 5

[0098] In this embodiment, the total effective focal length f of the imaging lens is 7.62 mm, the distance TTL along the optical axis from the object-side surface S1 of the first lens element E1 to the imaging surface S19 is 8.93 mm, half the diagonal length of the effective pixel area on the imaging surface S19 ImgH is 8.42 mm, half the maximum field of view (Semi-FOV) of the imaging lens is 47.1°, and the aperture value FNO of the imaging lens is 1.90.

[0099] Table 6 shows the high-order coefficients A4, A6, A8, A10, A12, A14, A16, A18, A20, A22, A24, A26, A28 and A30 of each mirror surface that can be used in the aspheric surfaces S1 to S16 in Example 3, wherein the surface shape of each aspheric surface can be defined by formula (1) given in the above Example 1.

[0100]

[0101] Table 6

[0102] Figure 6A The axial chromatic aberration curve of the imaging lens of Example 3 is shown, which indicates the deviation of the convergent focus of light of different wavelengths after passing through the imaging lens. Figure 6B The astigmatism curve of the imaging lens of Example 3 is shown, which indicates meridional field curvature and sagittal field curvature. Figure 6C The distortion curve of the imaging lens of Example 3 is shown, which represents the distortion magnitude values ​​corresponding to different image heights. Figure 6D The chromatic aberration curve of the imaging lens of Example 3 is shown, which represents the deviation of different image heights on the imaging surface after the light passes through the lens. 6A to 6D It can be seen that the imaging lens provided in Example 3 can achieve good imaging quality.

[0103] Example 4

[0104] The following reference Figures 7 to 8D The imaging lens according to embodiment 4 of the present application is described. Figure 7 As shown, the imaging lens includes, from the object side to the image side along the optical axis, an aperture STO, 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, an eighth lens E8, a filter E9 and an imaging surface S19.

[0105] The first lens E1 has positive focal power, with its object-side surface S1 being convex and its image-side surface S2 being concave. The second lens E2 has negative focal power, with its object-side surface S3 being convex and its image-side surface S4 being concave. The third lens E3 has positive focal power, with its object-side surface S5 being convex and its image-side surface S6 being concave. The fourth lens E4 has negative focal power, with its object-side surface S7 being concave and its image-side surface S8 being convex. The fifth lens E5 has positive focal power, with its object-side surface S9 being concave and its image-side surface S10 being convex. The sixth lens E6 has negative focal power, with its object-side surface S11 being convex and its image-side surface S12 being concave. The seventh lens E7 has positive focal power, with its object-side surface S13 being convex and its image-side surface S14 being convex. The eighth lens E8 has negative focal power, with its object-side surface S15 being concave and its image-side surface S16 being concave. The optical filter E9 has an object-side surface S17 and an image-side surface S18. Light from an object passes through the surfaces S1 to S18 in sequence and is finally imaged on the imaging surface S19 .

[0106] Table 7 shows the basic parameters of the imaging lens of Example 4, where the units of curvature radius, thickness / distance, and focal length are all millimeters (mm).

[0107]

[0108] Table 7

[0109] In this embodiment, the total effective focal length f of the imaging lens is 7.37 mm, the distance TTL along the optical axis from the object-side surface S1 of the first lens element E1 to the imaging surface S19 is 8.93 mm, half the diagonal length of the effective pixel area on the imaging surface S19 ImgH is 7.35 mm, half the maximum field of view (Semi-FOV) of the imaging lens is 44.5°, and the aperture value FNO of the imaging lens is 1.90.

[0110] Table 8 shows the high-order coefficients A4, A6, A8, A10, A12, A14, A16, A18, A20, A22, A24, A26, A28 and A30 of each mirror surface that can be used in the aspheric surfaces S1 to S16 in Example 4, wherein the surface shape of each aspheric surface can be defined by the formula (1) given in the above-mentioned Example 1.

[0111]

[0112] Table 8

[0113] Figure 8A The axial chromatic aberration curve of the imaging lens of Example 4 is shown, which indicates the deviation of the convergent focus of light of different wavelengths after passing through the imaging lens. Figure 8B The astigmatism curve of the imaging lens of Example 4 is shown, which indicates meridional field curvature and sagittal field curvature. Figure 8C The distortion curve of the imaging lens of Example 4 is shown, which represents the distortion magnitude values ​​corresponding to different image heights. Figure 8D The chromatic aberration curve of the imaging lens of Example 4 is shown, which represents the deviation of different image heights on the imaging surface after the light passes through the lens. Figures 8A to 8D It can be seen that the imaging lens provided in Example 4 can achieve good imaging quality.

[0114] Example 5

[0115] The following reference Figures 9 to 10D The imaging lens according to Example 5 of the present application is described. Figure 9 As shown, the imaging lens includes, from the object side to the image side along the optical axis, an aperture STO, 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, an eighth lens E8, a filter E9 and an imaging surface S19.

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

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

[0118]

[0119] Table 9

[0120] In this embodiment, the total effective focal length f of the imaging lens is 7.37 mm, the distance TTL along the optical axis from the object-side surface S1 of the first lens element E1 to the imaging surface S19 is 8.93 mm, half the diagonal length of the effective pixel area on the imaging surface S19 ImgH is 6.94 mm, half the maximum field of view (Semi-FOV) of the imaging lens is 43.0°, and the aperture value FNO of the imaging lens is 1.90.

[0121] Table 10 shows the high-order coefficients A4, A6, A8, A10, A12, A14, A16, A18, A20, A22, A24, A26, A28 and A30 of each mirror surface that can be used in the aspheric surfaces S1 to S16 in Example 5, wherein the surface shape of each aspheric surface can be defined by the formula (1) given in the above Example 1.

[0122]

[0123] Table 10

[0124] Figure 10A The axial chromatic aberration curve of the imaging lens of Example 5 is shown, which indicates the deviation of the convergent focus of light of different wavelengths after passing through the imaging lens. Figure 10B The astigmatism curve of the imaging lens of Example 5 is shown, which indicates meridional field curvature and sagittal field curvature. Figure 10C The distortion curve of the imaging lens of Example 5 is shown, which represents the distortion magnitude values ​​corresponding to different image heights. Figure 10D The chromatic aberration curve of the imaging lens of Example 5 is shown, which represents the deviation of the different image heights on the imaging surface after the light passes through the lens. 10A to 10D It can be seen that the imaging lens provided in Example 5 can achieve good imaging quality.

[0125] Example 6

[0126] The following reference Figures 11 to 12D The imaging lens according to Example 6 of the present application is described. Figure 11 As shown, the imaging lens includes, from the object side to the image side along the optical axis, an aperture STO, 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, an eighth lens E8, a filter E9 and an imaging surface S19.

[0127] The first lens E1 has positive focal power, with its object-side surface S1 being convex and its image-side surface S2 being concave. The second lens E2 has negative focal power, with its object-side surface S3 being convex and its image-side surface S4 being concave. The third lens E3 has positive focal power, with its object-side surface S5 being convex and its image-side surface S6 being concave. The fourth lens E4 has negative focal power, with its object-side surface S7 being concave and its image-side surface S8 being convex. The fifth lens E5 has positive focal power, with its object-side surface S9 being convex and its image-side surface S10 being convex. The sixth lens E6 has negative focal power, with its object-side surface S11 being convex and its image-side surface S12 being concave. The seventh lens E7 has positive focal power, with its object-side surface S13 being convex and its image-side surface S14 being convex. The eighth lens E8 has negative focal power, with its object-side surface S15 being concave and its image-side surface S16 being concave. The optical filter E9 has an object-side surface S17 and an image-side surface S18. Light from an object passes through the surfaces S1 to S18 in sequence and is finally imaged on the imaging surface S19 .

[0128] Table 11 shows the basic parameters of the imaging lens of Example 6, where the units of curvature radius, thickness / distance, and focal length are all millimeters (mm).

[0129]

[0130] Table 11

[0131] In this embodiment, the total effective focal length f of the imaging lens is 7.41 mm, the distance TTL along the optical axis from the object-side surface S1 of the first lens element E1 to the imaging surface S19 is 8.93 mm, half the diagonal length of the effective pixel area on the imaging surface S19 ImgH is 8.17 mm, half the maximum field of view Semi-FOV of the imaging lens is 47.0°, and the aperture value FNO of the imaging lens is 1.90.

[0132] Table 12 shows the high-order coefficients A4, A6, A8, A10, A12, A14, A16, A18, A20, A22, A24, A26, A28 and A30 of each mirror surface that can be used in the aspheric surfaces S1 to S16 in Example 6, wherein the surface shape of each aspheric surface can be defined by formula (1) given in the above Example 1.

[0133]

[0134] Table 12

[0135] Figure 12A The axial chromatic aberration curve of the imaging lens of Example 6 is shown, which indicates the deviation of the convergent focus of light of different wavelengths after passing through the imaging lens. Figure 12B The astigmatism curve of the imaging lens of Example 6 is shown, which indicates meridional field curvature and sagittal field curvature. Figure 12C The distortion curve of the imaging lens of Example 6 is shown, which represents the distortion magnitude values ​​corresponding to different image heights. Figure 12D The chromatic aberration curve of the imaging lens of Example 6 is shown, which represents the deviation of the different image heights on the imaging surface after the light passes through the lens. 12A to 12D It can be seen that the imaging lens provided in Example 6 can achieve good imaging quality.

[0136] In summary, Examples 1 to 6 respectively satisfy the relationships shown in Table 13.

[0137]

[0138] Table 13

[0139] The above description is merely a preferred embodiment of the present application and an illustration of the technical principles employed. Those skilled in the art should understand that the scope of the invention herein is not limited to technical solutions formed by a specific combination of the aforementioned technical features. It also encompasses other technical solutions formed by any combination of the aforementioned technical features or their equivalents, without departing from the inventive concept. For example, a technical solution formed by replacing the aforementioned features with (but not limited to) technical features with similar functions disclosed in this application.

Claims

1. An imaging lens, characterized in that: Along the optical axis from the object side to the image side, they include: The first lens has positive power, a convex object-side surface, a concave image-side surface, and is made of glass; The second lens has negative optical power, its object-side surface is convex, and its image-side surface is concave; The third lens has positive optical power, its object-side surface is convex, and its image-side surface is concave; The fourth lens has negative optical power and its object-side surface is concave; The fifth lens has positive refractive power and its image-side surface is convex; The sixth lens has negative optical power, its object-side surface is convex, and its image-side surface is concave; The seventh lens has positive optical power, its object-side surface is convex, and its image-side surface is convex; The eighth lens has negative optical power, and its object-side surface and image-side surface are concave; The number of lenses having optical power in the imaging lens is eight, and the imaging lens satisfies: 1.06≤TTL / ImgH≤1.29, 0.71≤(CT5+CT6) / (T56+T67)≤0.84, and 1.66≤CT3 / CT4≤1.99; Wherein, TTL is the distance from the object-side surface of the first lens to the imaging surface of the imaging lens along the optical axis, ImgH is half the diagonal length of the effective pixel area on the imaging surface, CT5 is the center thickness of the fifth lens on the optical axis, CT6 is the center thickness of the sixth lens on the optical axis, T56 is the air gap between the fifth lens and the sixth lens along the optical axis, T67 is the air gap between the sixth lens and the seventh lens along the optical axis, CT3 is the center thickness of the third lens on the optical axis, and CT4 is the center thickness of the fourth lens on the optical axis.

2. The imaging lens according to claim 1, wherein: The imaging lens satisfies: 0.60≤f123 / (f1+f2+f3)≤0.84, Wherein, f1 is the effective focal length of the first lens, f2 is the effective focal length of the second lens, f3 is the effective focal length of the third lens, and f123 is the combined focal length of the first lens, the second lens, and the third lens.

3. The imaging lens according to claim 1, wherein: The imaging lens satisfies: 7.63≤(R11+R12) / (R11-R12)≤15.76, Wherein, R11 is the curvature radius of the object-side surface of the sixth lens, and R12 is the curvature radius of the image-side surface of the sixth lens.

4. The imaging lens according to claim 1, wherein: The imaging lens satisfies: 1.0 <T56 / T34≤1.33, Wherein, T34 is the air gap between the third lens and the fourth lens along the optical axis.

5. The imaging lens according to claim 4, wherein: The imaging lens satisfies: 1.18≤CT5 / CT8≤2.16, Wherein, CT8 is the center thickness of the eighth lens on the optical axis.

6. The imaging lens according to claim 1, wherein: The imaging lens satisfies: 47.1°≥Semi-FOV>42°, Wherein, Semi-FOV is half of the maximum field of view of the imaging lens.

7. The imaging lens according to claim 1, wherein: The imaging lens satisfies: 8.42mm≥ImgH>5.5 mm.

8. The imaging lens according to claim 5, wherein: The imaging lens satisfies: 0.59≤(CT7+CT8) / T78≤0.77, Wherein, CT7 is the center thickness of the seventh lens on the optical axis, CT8 is the center thickness of the eighth lens on the optical axis, and T78 is the air spacing between the seventh lens and the eighth lens along the optical axis.

9. The imaging lens according to any one of claims 1 to 8, wherein: Any lens from the second lens to the eighth lens is made of plastic, wherein the refractive index of any lens is greater than 1.

5.

10. The imaging lens according to claim 1, wherein: The imaging lens satisfies: 34.37≤Vg≤57.06, Wherein, Vg is the dispersion coefficient of the first lens.

11. The imaging lens according to claim 9, wherein: The imaging lens satisfies: 9.09≤1 / (Npmax-Ng)≤25.00, Wherein, Npmax is the maximum value of the refractive index of each lens from the second lens to the eighth lens, and Ng is the refractive index of the first lens.

12. The imaging lens according to claim 4, wherein: The imaging lens satisfies: 1.91≤T23 / T12≤3.84, Wherein, T12 is the air distance between the first lens and the second lens along the optical axis, and T23 is the air distance between the second lens and the third lens along the optical axis.

13. The imaging lens according to claim 3, wherein: The imaging lens satisfies: -0.97≤R16 / R15≤-0.63, Wherein, R15 is the curvature radius of the object side surface of the eighth lens, and R16 is the curvature radius of the image side surface of the eighth lens.

14. The imaging lens according to claim 1, wherein: The imaging lens satisfies: 1.12≤ET8 / ET1≤4.70, ET1 is the edge thickness of the first lens at the maximum effective diameter, and ET8 is the edge thickness of the eighth lens at the maximum effective diameter.

15. The imaging lens according to claim 1, wherein: The imaging lens satisfies: -6.93≤(f6+f7) / f67≤-3.04, Wherein, f6 is the effective focal length of the sixth lens, f7 is the effective focal length of the seventh lens, and f67 is the combined focal length of the sixth lens and the seventh lens.

16. The imaging lens according to claim 15, wherein: The imaging lens satisfies: -0.10≤f / f4<0, Wherein, f is the total effective focal length of the imaging lens, and f4 is the effective focal length of the fourth lens.

Images