Imaging lenses, camera modules and electronic devices

Abstract

The present invention relates to an imaging lens, a camera module and an electronic device. The imaging lens includes, from the object side to the image side, a first lens with refractive power, the object side surface of the first lens is a convex surface at the optical axis; a second lens with refractive power, the object side surface of the second lens is a convex surface at the optical axis; a third lens with refractive power; the imaging lens satisfies FNO*L>15.5; wherein FNO is the aperture number of the imaging lens, L is the aperture diameter of the first lens, and the unit of L is mm. When the above relationship is met, the optical system will have a larger focal length range to meet the telephoto characteristics, and the focal length is longer than that of a general telephoto system. At the same time, the optical system also has a light transmittance that matches the focal length range to improve the brightness of the picture during telephoto shooting, so that the optical system will be beneficial to improving the shooting quality when applied to telephoto shooting.

Description

Technical Field

[0001] The present invention relates to the field of optical imaging, and in particular to an imaging lens, a camera module and an electronic device. Background Art

[0002] With the continuous advancement of mobile phone camera technology, people are placing increasingly higher demands on mobile phone cameras. Among them, telephoto lenses offer advantages over standard lenses, such as a longer focal length, a narrower angle of view, and a larger image on film. As a result, telephoto lenses can capture larger images than standard lenses at the same shooting distance, making them suitable for capturing distant scenes. Furthermore, because telephoto lenses have a narrower depth of field than standard lenses, they can more effectively blur the background and highlight the in-focus subject, making the captured images more vivid. However, obtaining a lens with a longer focal length can make it difficult to ensure sufficient light transmission, resulting in darker images and lower quality. Summary of the Invention

[0003] Based on this, it is necessary to provide an imaging lens, a camera module and an electronic device to solve the problem of how to achieve telephoto characteristics and improve the brightness of the captured image.

[0004] An imaging lens, comprising, from the object side to the image side, the following components:

[0005] a first lens having refractive power, wherein the object-side surface of the first lens is convex at the optical axis;

[0006] a second lens having refractive power, wherein the object-side surface of the second lens is convex at the optical axis;

[0007] a third lens having refractive power;

[0008] The imaging lens satisfies the following relationship:

[0009] FNO*L>15.5;

[0010] Wherein, FNO is the aperture number of the imaging lens, L is the aperture diameter of the first lens, and the unit of L is mm.

[0011] When the above relationship is met, the optical system will have a larger focal length range to meet the telephoto characteristics, and the focal length will be longer than that of a general telephoto system. At the same time, the optical system also has a light transmittance that matches the focal length range to improve the image brightness during telephoto shooting. Therefore, the optical system will be beneficial to improving the shooting quality when used for telephoto shooting. However, when FNO*L is less than 15.5, although the optical system has sufficient light transmittance to ensure the contrast of the captured image, it is difficult to ensure that the optical system has the telephoto characteristics.

[0012] In one embodiment, the imaging lens satisfies the relationship:

[0013] 1<(ΣET*EPD) / f<3;

[0014] Where ΣET is the distance from the aperture to the maximum effective radius of the image-side surface of the third lens in a direction parallel to the optical axis, EPD is the entrance pupil diameter of the imaging lens, and f is the effective focal length of the imaging lens. ΣET determines the total edge length of the optical system, while EPD is the entrance pupil diameter of the optical system. That is, ΣET*EPD determines the size of the entire optical system. Therefore, when the above relationship is satisfied, both the miniaturization design and telephoto performance of the imaging lens can be achieved. If (ΣET*EPD) / f≥3, the system volume will be too large and will not meet the miniaturization design requirements. When (ΣET*EPD) / f≤1, the system volume will be too small, making aberration correction difficult and the optical performance parameters will not meet the design requirements.

[0015] In one embodiment, the imaging lens satisfies the relationship:

[0016] -37<f1 / CT1<22;

[0017] Where f1 is the focal length of the first lens, and CT1 is the thickness of the first lens at the optical axis. The ratio between the focal length and thickness of the first lens determines how the second and third lenses are combined to balance the aberrations generated by the first lens. When f1 / CT1 ≥ 22, system aberration correction is difficult. When f1 / CT1 ≤ -37, the angle of light emitted from the image-side surface of the first lens increases, resulting in a smaller focal length of the first lens, which cannot provide sufficient focal length for the system.

[0018] In one embodiment, the imaging lens satisfies the relationship:

[0019] 1.0<TTL / |f|<1.2;

[0020] Wherein, TTL is the distance from the object side of the first lens to the imaging plane of the imaging lens on the optical axis, and f is the effective focal length of the imaging lens. The three lenses in the imaging lens cooperate with each other, and when the above relationship is satisfied, the length of the imaging lens is reasonably adjusted to avoid the length of the lens being too long, thereby meeting the requirements of reasonable focal length and miniaturization design. When TTL / |f|≤1.0, the optical length of the lens group is too short, which will increase the sensitivity of the system and make it difficult to correct aberrations. When TTL / |f|≥1.2, the optical length of the lens group is too long, resulting in a large main ray angle for light entering the imaging plane, which makes the effective focal length of the imaging lens smaller, and cannot meet the reasonable focal length, thus making it impossible to achieve a telephoto design.

[0021] In one embodiment, the imaging lens satisfies the relationship:

[0022] 0.7<TTL / |f1|<2.7;

[0023] Wherein, TTL is the distance from the object side of the first lens to the imaging surface of the imaging lens on the optical axis, and f1 is the focal length of the first lens. When the above relationship is satisfied, it is beneficial to correct the aberrations of the optical system. When TTL / |f1|≤0.7, the optical length of the imaging lens is too short, which will increase the sensitivity of the system and make aberration correction difficult. When TTL / |f1|≥2.7, the optical length of the imaging lens is too large to match the focal length of the first lens. It is difficult for the second and third lenses to balance the aberrations generated by the first lens, resulting in poor imaging quality and failure to meet shooting requirements.

[0024] In one embodiment, the imaging lens satisfies the relationship:

[0025] -585<(f2+f3) / CT2<30;

[0026] Where f2 is the focal length of the second lens, f3 is the focal length of the third lens, and CT2 is the thickness of the second lens at the optical axis. When this relationship is satisfied, the second and third lenses can effectively distribute the refractive power, balancing the aberrations produced by the first lens, reducing system tolerance sensitivity, and improving system imaging quality. When (f2 + f3) / CT2 ≤ -585, the center thickness of the second lens is too thick, resulting in an excessively long optical system. When (f2 + f3) / CT2 ≥ 30, the center thickness of the second lens is too thin, making manufacturing difficult.

[0027] In one embodiment, the imaging lens satisfies the relationship:

[0028] -0.8<f23 / f<10;

[0029] Where f23 is the combined focal length of the second and third lenses, and f is the effective focal length of the imaging lens. When this relationship is met, the refractive power of the second and third lenses can be rationally distributed to effectively correct system aberrations. When f23 / f ≥ 10, the refractive power provided by the second and third lenses is insufficient, making it difficult to correct system aberrations. When f23 / f ≤ -0.8, and if the second and third lenses are plastic lenses, the focal position of the imaging lens can vary significantly with temperature, increasing the tolerance sensitivity of the imaging lens.

[0030] In one embodiment, the imaging lens satisfies the relationship:

[0031] -5<R2 / f1<5;

[0032] Wherein, R2 is the radius of curvature of the image side surface of the first lens at the optical axis, and f1 is the focal length of the first lens. When the above relationship is satisfied, the image side surface of the first lens has an appropriate radius of curvature at the optical axis, which is conducive to correcting aberrations. When R2 / f1≤-5, the radius of curvature of the image side surface of the first lens at the optical axis is too large, the surface curvature becomes larger, the molding yield is low, and the lens manufacturing is difficult. When R2 / f1≥5, the radius of curvature of the image side surface of the first lens at the optical axis is not appropriately matched with the focal length of the first lens, resulting in excessive aberrations of the optical system and difficulty in correction.

[0033] In one embodiment, the imaging lens satisfies the relationship:

[0034] 11<BFL<16;

[0035] Wherein, BFL is the shortest distance from the image-side surface of the third lens to the imaging plane of the imaging lens in a direction parallel to the optical axis, and the unit of BFL is mm. When this relationship is met, the system can ensure a sufficient focusing range during assembly, improving the assembly yield of the lens module. At the same time, it can also enable the imaging lens to have a larger depth of focus, which is conducive to obtaining more depth information from the object side.

[0036] In one embodiment, the imaging lens satisfies the relationship:

[0037] 91<TTL / SL<3450;

[0038] Where TTL is the distance from the object side of the first lens to the imaging plane of the imaging lens on the optical axis, and SL is the distance from the aperture to the maximum effective radius of the object side of the first lens, parallel to the optical axis. When TTL / SL > 3450, the system is too long and cannot meet the requirements of miniaturization. When TTL / SL < 91, the system cannot correct for marginal spherical aberration. When the total optical length of the system is fixed, the aperture blocks light from the edge of the lens, thereby correcting spherical aberration. If the aperture is not properly allocated to the total optical length, the expected imaging quality cannot be achieved.

[0039] In one embodiment, the imaging lens satisfies the relationship:

[0040] 0.13<ΣET(len) / TTL<0.25;

[0041] Where ΣET(len) is the combined thickness of the first, second, and third lenses at their maximum effective radius, and TTL is the distance from the object-side surface of the first lens to the imaging plane of the imaging lens on the optical axis. When ΣET(len) / TTL is less than 0.13, the edge thickness may be too thin, making the production process difficult and the assembly stability poor. When ΣET(len) / TTL is greater than 0.25, the optical system becomes too long, failing to meet the original goal of miniaturization.

[0042] In one embodiment, the imaging lens satisfies the relationship:

[0043] 0.06<ET12 / f<0.2;

[0044] Where ET12 is the combined thickness of the first and second lenses at their maximum effective radius, and f is the effective focal length of the imaging lens. If ET12 / f > 0.2, the imaging lens will not meet the manufacturing requirements while failing to provide telephoto characteristics. When ET12 / f < 0.06, the system will suffer from poor sensitivity, making it difficult to manufacture.

[0045] In one embodiment, the imaging lens further includes a reflector, which is disposed on the object side of the first lens. Light carrying information of the object can be reflected by the reflector to the first lens.

[0046] A camera module includes a photosensitive element and the imaging lens described in the above embodiment, wherein the photosensitive element is arranged on the image side of the imaging lens.

[0047] In one embodiment, the photosensitive element is disposed on the imaging surface of the imaging lens, and the camera module satisfies the relationship:

[0048] 4<TTL / Imgh<8;

[0049] Where TTL is the distance from the object side of the first lens to the imaging plane of the imaging lens on the optical axis, and Imgh is half the diagonal length of the effective pixel area of ​​the photosensitive element. When TTL / Imgh is less than 4, the photosensitive element will not fully receive light information, and edge light will hit the edge of the photosensitive element, generating stray light. When TTL / Imgh is greater than 8, the total length of the system will not match the image height, resulting in incomplete imaging or excessive system length.

[0050] An electronic device comprises the camera module described in any one of the above embodiments. BRIEF DESCRIPTION OF THE DRAWINGS

[0051] Figure 1 A schematic diagram of an imaging lens provided in the first embodiment of the present application;

[0052] Figure 2 Graphs for longitudinal spherical aberration (mm), astigmatism (mm), and distortion (%) of the imaging lens in the first embodiment are shown below:

[0053] Figure 3 A schematic diagram of an imaging lens provided in a second embodiment of the present application;

[0054] Figure 4 Graphs for longitudinal spherical aberration (mm), astigmatism (mm), and distortion (%) of the imaging lens in the second embodiment are shown below:

[0055] Figure 5 A schematic diagram of an imaging lens provided in a third embodiment of the present application;

[0056] Figure 6 Graphs for longitudinal spherical aberration (mm), astigmatism (mm), and distortion (%) of the imaging lens in the third embodiment are shown below:

[0057] Figure 7 A schematic diagram of an imaging lens provided in a fourth embodiment of the present application;

[0058] Figure 8 Graphs for longitudinal spherical aberration (mm), astigmatism (mm), and distortion (%) of the imaging lens in the fourth embodiment are shown below:

[0059] Figure 9 A schematic diagram of an imaging lens provided in a fifth embodiment of the present application;

[0060] Figure 10 Graphs for longitudinal spherical aberration (mm), astigmatism (mm), and distortion (%) of the imaging lens in the fifth embodiment are shown below:

[0061] Figure 11 A schematic diagram of a camera module provided in one embodiment of the present application;

[0062] Figure 12 A schematic diagram of a camera module provided in another embodiment of the present application;

[0063] Figure 13 A schematic diagram of an electronic device provided in one embodiment of the present application. DETAILED DESCRIPTION

[0064] To facilitate understanding of the present invention, the present invention will be described more fully below with reference to the accompanying drawings. The drawings illustrate preferred embodiments of the present invention. However, the present invention may be embodied in many different forms and is not limited to the embodiments described herein. Rather, these embodiments are provided to provide a more thorough and comprehensive disclosure of the present invention.

[0065] It should be noted that when an element is referred to as being "fixed to" another component, it may be directly on the other component or there may be a central element. When an element is considered to be "connected to" another component, it may be directly connected to the other component or there may be a central element at the same time. In contrast, when an element is referred to as being "directly on" another component, there is no intermediate element. The terms "vertical," "horizontal," "left," "right," and similar expressions used herein are for illustrative purposes only.

[0066] Unless otherwise defined, all technical and scientific terms used herein have the same meaning as commonly understood by one skilled in the art to which this invention pertains. The terms used in this specification are for the purpose of describing specific embodiments only and are not intended to limit the present invention. The term "and / or" as used herein includes any and all combinations of one or more of the associated listed items.

[0067] refer to Figure 1 As shown, the present application provides an imaging lens 100. The imaging lens 100 includes, from the object side to the image side, a first lens L1 having refractive power, a second lens L2 having refractive power, and a third lens L3 having refractive power.

[0068] The first lens element L1 includes an object-side surface S1 and an image-side surface S2; the second lens element L2 includes an object-side surface S3 and an image-side surface S4; and the third lens element L3 includes an object-side surface S5 and an image-side surface S6. Furthermore, the image side of the third lens element L3 includes an imaging surface S9, which can be the photosensitive surface of a photosensitive element. The object-side surface S1 of the first lens element L1 is convex along the optical axis, while the object-side surface S3 of the second lens element L2 is also convex along the optical axis.

[0069] In addition, it should be noted that the system or optical system described below can be composed of components such as a reflector, an imaging lens 100, and a filter.

[0070] In some embodiments, the first lens L1, the second lens L2, and the third lens L3 are all made of plastic, thereby reducing production costs and weight. In other embodiments, the first lens L1, the second lens L2, and the third lens L3 are all made of glass, as glass lenses have better optical performance. Preferably, the first lens L1 can be a glass lens, as glass lenses have higher heat resistance, thereby preventing lens aging and degradation of optical performance in high-temperature environments. It should be noted that, depending on actual production needs, the materials of the first lens L1, the second lens L2, and the third lens L3 can be arbitrarily combined and are not limited here.

[0071] In some embodiments, a stop ST0 is disposed on the object side of the first lens element L1. In other embodiments, a stop ST0 may be disposed between the first lens element L1 and the third lens element L3. The stop ST0 can limit the amount of light passing through the imaging lens element 100.

[0072] When describing that the aperture STO is arranged on the object side of the first lens L1, or describing that the imaging lens 100 is sequentially provided with elements such as the aperture STO, the first lens L1, and the second lens L2 from the object side to the image side, the projection of the aperture STO on the optical axis of the first lens L1 can overlap with the projection of the first lens L1 on the optical axis, or can also not overlap.

[0073] In some embodiments, an infrared cutoff filter L4 is provided on the image side of the third lens element L3. The infrared cutoff filter L4 includes an object-side surface S7 and an image-side surface S8. The infrared cutoff filter L4 allows visible light to pass through while blocking infrared light, preventing infrared light from reaching the photosensitive element and affecting visible light imaging, thereby improving the imaging quality of the imaging lens 100 during daytime. It should be noted that the infrared cutoff filter L4 can be omitted from the imaging lens 100. Instead, the infrared cutoff filter L4 can be assembled between the imaging lens 100 and the photosensitive element during assembly.

[0074] refer to Figure 1 In some embodiments, the imaging lens 100 further includes a reflector 120, which is disposed on the object side of the first lens L1. Light carrying subject information can be reflected by the reflector 120 toward the lens group of the imaging lens 100 (composed of the first lens L1, the second lens L2, and the third lens L3). Specifically, the reflector 120 can be a prism disposed on the object side of the first lens L1. The prism can change the propagation direction of light by 90° to reflect it toward the first lens L1, the second lens L2, and the third lens L3. By providing the reflector 120, the imaging lens 100 can be more easily applied to miniaturized devices (especially those with a small thickness). In other embodiments, the reflector 120 can also be a plane reflector.

[0075] Specifically, in some embodiments, the prism includes an incident surface G1, a reflective surface G2, and an exit surface G3. The exit surface G3 is perpendicular to the optical axis of the first lens L1, and the reflective surface G2 forms a 45-degree angle with the exit surface G3. The incident surface G1 is perpendicular to the exit surface G3 and forms a 45-degree angle with the reflective surface G2. Light carrying subject information enters the prism through the incident surface G1, is then reflected by the reflective surface G2, and then exits the exit surface G3 to the first lens L1.

[0076] In some embodiments, the object-side surface and image-side surface of the first lens L1, the second lens L2, and the third lens L3 are all aspherical surfaces. The aspherical surface formula is:

[0077]

[0078] Where Z is the distance from the corresponding point on the aspheric surface to the plane tangent to the vertex of the surface, r is the distance from the corresponding point on the aspheric surface to the optical axis, c is the curvature of the aspheric vertex, k is the cone constant, and Ai is the coefficient corresponding to the i-th higher-order term in the aspheric surface shape formula.

[0079] In some embodiments, the imaging lens 100 satisfies the following relationship:

[0080] FNO*L>15.5;

[0081] Wherein, FNO is the aperture number of the imaging lens 100, L is the aperture diameter of the first lens L1, and the unit of L is mm. Specifically, FNO*L can be 17.50, 17.55, 17.60, 17.65, 17.70, 17.73, or 17.74. When the above relationship is satisfied, the optical system will have a larger focal length range to meet the telephoto characteristic, and the focal length is longer than that of a typical telephoto system. At the same time, the optical system also has a light transmission that matches the focal length range to improve the image brightness during telephoto shooting. Therefore, the optical system will be beneficial for improving the shooting quality when used for telephoto shooting. When FNO*L is less than 15.5, although the optical system has sufficient light transmission to ensure the contrast of the captured image, it is difficult to ensure that the optical system has the telephoto characteristic.

[0082] In some embodiments, the imaging lens 100 satisfies the relationship:

[0083] 1<(ΣET*EPD) / f<3;

[0084] Wherein, ΣET is the distance from the aperture STO to the maximum effective radius of the image-side surface S6 of the third lens L3 in a direction parallel to the optical axis, EPD is the entrance pupil diameter of the imaging lens 100, and f is the effective focal length of the imaging lens 100. Specifically, the relationship (ΣET*EPD) / f can be 1.15, 1.35, 1.55, 1.75, 1.95, 2.15, 2.35, or 2.40. ΣET determines the total edge length of the optical system, while EPD is the size of the entrance pupil diameter of the optical system, that is, ΣET*EPD determines the size of the entire optical system. Therefore, when the above relationship is met, the miniaturization design and telephoto performance of the imaging lens 100 can be simultaneously met; if (ΣET*EPD) / f≥3, the system volume will be too large and will not meet the miniaturization design requirements; when (ΣET*EPD) / f≤1, the system volume will be too small, phase aberration correction will be difficult, and the optical performance parameters will not meet the design requirements.

[0085] In some embodiments, the imaging lens 100 satisfies the relationship:

[0086] -37<f1 / CT1<22;

[0087] Where f1 is the focal length of the first lens L1, and CT1 is the thickness of the first lens L1 at the optical axis. Specifically, the ratio f1 / CT1 can be -35.00, -25.00, -15.00, -5.00, 5.00, 10.00, or 15.00. The ratio between the focal length and thickness of the first lens L1 determines how the second lens L2 and the third lens L3 are combined to balance the aberrations generated by the first lens L1. When f1 / CT1 ≥ 22, system aberration correction becomes difficult. When f1 / CT1 ≤ -37, the angle of light emitted from the image-side surface S2 of the first lens L1 increases, resulting in a smaller focal length of the first lens L1, which cannot provide sufficient focal length for the system.

[0088] In some embodiments, the imaging lens 100 satisfies the relationship:

[0089] 1.0<TTL / |f|<1.2;

[0090] Where TTL is the distance on the optical axis from the object-side surface S1 of the first lens L1 to the imaging surface S9 of the imaging lens 100, and f is the effective focal length of the imaging lens 100. Specifically, the relationship TTL / |f| can be 1.03, 1.05, 1.07, 1.09, 1.11, 1.13, 1.15, or 1.17. The three lenses in the imaging lens 100 work together, and when the above relationship is satisfied, the length of the imaging lens 100 is properly adjusted, avoiding excessive length, thereby meeting the requirements of a reasonable focal length and miniaturization design. When TTL / |f| ≤ 1.0, the optical length of the lens group is too short, resulting in increased system sensitivity and difficulty in correcting aberrations. When TTL / |f| ≥ 1.2, the optical length of the lens group is too long, resulting in a large chief ray angle entering the imaging surface S9, which reduces the effective focal length of the imaging lens 100, making it impossible to meet a reasonable focal length and thus failing to achieve a telephoto design.

[0091] In some embodiments, the imaging lens 100 satisfies the relationship:

[0092] 0.7<TTL / |f1|<2.7;

[0093] Wherein, TTL is the distance on the optical axis from the object-side surface S1 of the first lens L1 to the imaging surface S9 of the imaging lens 100, and f1 is the focal length of the first lens L1. Specifically, the relationship of TTL / |f1| can be 0.90, 0.95, 1.00, 1.20, 1.50, 2.00 or 2.50. When the above relationship is satisfied, it is beneficial to correct the aberration of the optical system. When TTL / |f1|≤0.7, the optical length of the imaging lens 100 is too short, which will increase the sensitivity of the system and make it difficult to correct the aberration. When TTL / |f1|≥2.7, the optical length of the imaging lens 100 is too large to match the focal length of the first lens L1. It is difficult for the second lens L2 and the third lens combination to balance the aberration generated by the first lens L1, resulting in poor imaging quality and failure to meet shooting requirements.

[0094] In some embodiments, the imaging lens 100 satisfies the relationship:

[0095] -585<(f2+f3) / CT2<30;

[0096] Where f2 is the focal length of the second lens L2, f3 is the focal length of the third lens L3, and CT2 is the thickness of the second lens L2 at the optical axis. Specifically, the relationship (f2+f3) / CT2 can be -570.00, -5.00, -1.00, 1.00, 20.00, 25.00, or 28.00. When the above relationship is met, the second lens L2 and the third lens L3 can reasonably distribute the refractive power to balance the aberrations generated by the first lens L1, reduce the system's tolerance sensitivity, and improve the system's imaging quality. When (f2+f3) / CT2≤-585, the center thickness of the second lens L2 is too thick, resulting in an excessively long optical system. When (f2+f3) / CT2≥30, the center thickness of the second lens L2 is too thin, making manufacturing difficult.

[0097] In some embodiments, the imaging lens 100 satisfies the relationship:

[0098] -0.8<f23 / f<10;

[0099] Where f23 is the combined focal length of the second lens L2 and the third lens L3, and f is the effective focal length of the imaging lens 100. Specifically, the relationship f23 / f can be -0.70, -0.65, 0.30, 0.55, 3.00, 3.60, 9.00, or 9.30. When this relationship is satisfied, the refractive power of the second lens L2 and the third lens L3 can be rationally distributed to effectively correct systematic aberrations. When f23 / f ≥ 10, the refractive power provided by the second lens L2 and the third lens L3 is insufficient, making it difficult to correct systematic aberrations. When f23 / f ≤ -0.8, and if the second lens L2 and the third lens L3 are plastic lenses, the focal position of the imaging lens 100 will vary significantly with temperature, resulting in increased tolerance sensitivity of the imaging lens 100.

[0100] In some embodiments, the imaging lens 100 satisfies the relationship:

[0101] -5<R2 / f1<5;

[0102] Wherein, R2 is the radius of curvature of the image side surface S2 of the first lens L1 at the optical axis, and f1 is the focal length of the first lens L1. Specifically, the relationship of R2 / f1 can be -4.00, -3.50, 0.20, 0.30, 0.80, 0.90, 4.00 or 4.50. When the above relationship is satisfied, the image side surface S2 of the first lens L1 has a suitable radius of curvature at the optical axis, which is conducive to correcting aberrations. When R2 / f1≤-5, the radius of curvature of the image side surface S2 of the first lens L1 at the optical axis is too large, the surface curvature becomes larger, the molding yield is low, and the lens manufacturing is difficult. When R2 / f1≥5, the radius of curvature of the image side surface S2 of the first lens L1 at the optical axis is not suitable for the focal length of the first lens L1, resulting in excessive aberrations of the optical system and difficulty in correction.

[0103] In some embodiments, the imaging lens 100 satisfies the relationship:

[0104] 11<BFL<16;

[0105] Wherein, BFL is the shortest distance between the image-side surface S6 of the third lens L3 and the imaging surface S9 of the imaging lens 100 in a direction parallel to the optical axis, and the unit of BFL is mm. Specifically, BFL can be 12.80, 13.40, 14.00, 14.60, 14.80, 15.30, or 15.50. When the above relationship is met, the system can ensure sufficient focusing range during assembly, improving the assembly yield of the lens module. At the same time, it can also enable the imaging lens 100 to have a larger depth of focus, which is conducive to obtaining more depth information from the object side.

[0106] In some embodiments, the imaging lens 100 satisfies the relationship:

[0107] 91<TTL / SL<3450;

[0108] Wherein, TTL is the distance on the optical axis from the object-side surface S1 of the first lens L1 to the imaging surface S9 of the imaging lens 100, and SL is the distance from the aperture STO to the maximum effective radius of the object-side surface S1 of the first lens L1 in a direction parallel to the optical axis. Specifically, the relationship TTL / SL can be 95.00, 100.00, 3100.00, 3200.00, 3300.00, or 3400.00. When TTL / SL>3450, the system is too long and cannot meet the requirements of miniature design; when TTL / SL<91, the system cannot correct marginal spherical aberration. When the total optical length of the system is fixed, the aperture STO has the function of blocking the light at the edge of the lens, thereby achieving the purpose of correcting spherical aberration. If the aperture STO is not properly distributed with respect to the total optical length, the expected imaging quality requirements cannot be achieved.

[0109] In some embodiments, the imaging lens 100 satisfies the relationship:

[0110] 0.13<ΣET(len) / TTL<0.25;

[0111] Wherein, ΣET(len) is the sum of the thicknesses of the first lens L1, the second lens L2, and the third lens L3 at their maximum effective radius, and TTL is the distance on the optical axis from the object-side surface S1 of the first lens L1 to the imaging surface S9 of the imaging lens 100. Specifically, the relationship ΣET(len) / TTL can be 0.16, 0.18, 0.19, 0.20, 0.22, or 0.23. When ΣET(len) / TTL is less than 0.13, the edge thickness may be too thin, making the production process difficult and the assembly stability poor. When ΣET(len) / TTL is greater than 0.25, the optical system may be too long, which does not meet the original intention of miniaturization design.

[0112] In some embodiments, the imaging lens 100 satisfies the relationship:

[0113] 0.06<ET12 / f<0.2;

[0114] Where ET12 is the sum of the thicknesses of the first lens element L1 and the second lens element L2 at their maximum effective radius, and f is the effective focal length of the imaging lens 100. Specifically, ET12 / f can be 0.08, 0.10, 0.12, 0.14, 0.15, 0.16, or 0.17. If ET12 / f > 0.2, the imaging lens 100 will not meet the telephoto requirements while meeting the manufacturing requirements. When ET12 / f < 0.06, the system sensitivity is poor, making it difficult to manufacture.

[0115] In some embodiments, the imaging lens 100 and the photosensitive element are assembled together to form a camera module. The photosensitive element is disposed on the imaging surface S9 of the imaging lens 100 , and the camera module satisfies the relationship:

[0116] 4<TTL / Imgh<8;

[0117] Wherein, TTL is the distance on the optical axis from the object-side surface S1 of the first lens L1 to the imaging surface S9 of the imaging lens 100, and Imgh is half the diagonal length of the effective pixel area of ​​the photosensitive element. Specifically, the relationship between TTL and Imgh can be 6.80, 6.90, 7.00, 7.20, 7.40, 7.60, or 7.70. When TTL / Imgh is less than 4, the photosensitive element will not fully receive light information, and marginal light will hit the edge of the photosensitive element, generating stray light. When TTL / Imgh is greater than 8, the total length of the system will not match the image height, resulting in incomplete imaging or excessive system length.

[0118] First embodiment

[0119] refer to Figure 1 In the first embodiment shown, the imaging lens 100 includes, from the object side to the image side, an aperture ST0, a first lens L1 with positive refractive power, a second lens L2 with negative refractive power, a third lens L3 with positive refractive power, and an infrared cut filter L4. Figure 2 1 is a longitudinal spherical aberration diagram (mm), an astigmatism diagram (mm), and a distortion diagram (%) of the imaging lens 100 in the first embodiment, wherein the astigmatism diagram and the distortion diagram are data diagrams at a reference wavelength.

[0120] The object-side surface S1 of the first lens L1 is convex along the optical axis, and the image-side surface S2 of the first lens L1 is concave along the optical axis; the object-side surface S1 of the first lens L1 is convex along the circumference, and the image-side surface S2 of the first lens L1 is concave along the circumference. The object-side surface S3 of the second lens L2 is convex along the optical axis, and the image-side surface S4 of the second lens L2 is concave along the optical axis; the object-side surface S3 of the second lens L2 is convex along the circumference, and the image-side surface S4 of the second lens L2 is concave along the circumference. The object-side surface S5 of the third lens L3 is concave along the optical axis, and the image-side surface S6 of the third lens L3 is convex along the optical axis; the object-side surface S5 of the third lens L3 is concave along the circumference, and the image-side surface S6 of the third lens L3 is convex along the circumference.

[0121] It should be noted that when a side surface of a lens is described as convex at the optical axis (the central area of ​​the side surface), it can be understood that the area of ​​the side surface of the lens near the optical axis is convex, and therefore the side surface can also be considered convex near the axis; when a side surface of a lens is described as concave at the circumference, it can be understood that the area of ​​the side surface near the maximum effective radius is concave. For example, when the side surface is convex at the optical axis and also convex at the circumference, the shape of the side surface from the center (optical axis) to the edge can be purely convex, or it can first transition from a convex shape at the center to a concave shape and then become convex near the maximum effective radius. This is only an example to illustrate the relationship between the optical axis and the circumference. The various shape structures (concave-convex relationship) of the side surface are not fully reflected, but other situations can be deduced based on the above examples.

[0122] The first lens L1 , the second lens L2 , and the third lens L3 are all made of plastic.

[0123] The object-side surfaces and image-side surfaces of the first lens L1 , the second lens L2 , and the third lens L3 are all aspherical surfaces.

[0124] Continue to refer Figure 1 In some embodiments, the imaging lens 100 further includes a prism, which is disposed on the object side of the first lens L1 and is configured to reflect light carrying subject information to the lens group consisting of the first lens L1, the second lens L2, and the third lens L3.

[0125] In addition, the imaging lens 100 also satisfies the following relationship:

[0126] FNO*L=17.44; where FNO is the aperture number of imaging lens 100, and L is the aperture diameter of first lens element L1, with L measured in mm. When this relationship is met, the optical system has a wider focal length range to meet telephoto requirements, and a longer focal length than typical telephoto systems. Furthermore, the optical system also provides sufficient light transmission to match the focal length range, enhancing image brightness during telephoto photography. Consequently, the optical system improves image quality when used for telephoto photography.

[0127] (ΣET * EPD) / f = 2.45; where ΣET is the distance from the aperture ST0 to the maximum effective radius of the image-side surface S6 of the third lens element L3, parallel to the optical axis, EPD is the entrance pupil diameter of the imaging lens 100, and f is the effective focal length of the imaging lens 100. ΣET determines the total edge length of the optical system, while EPD is the entrance pupil diameter. In other words, ΣET * EPD determines the size of the entire optical system. Therefore, when this relationship is met, the imaging lens 100 can achieve both miniaturization and telephoto performance.

[0128] f1 / CT1=8.64; wherein f1 is the focal length of the first lens L1, and CT1 is the thickness of the first lens L1 at the optical axis.

[0129] TTL / |f|=1.18; where TTL is the distance along the optical axis from the object-side surface S1 of the first lens L1 to the imaging surface S9 of the imaging lens 100, and f is the effective focal length of the imaging lens 100. The three lenses in the imaging lens 100 work together, and when the above relationship is satisfied, the length of the imaging lens 100 is appropriately adjusted, preventing the lens from being excessively long, thereby meeting the requirements of a reasonable focal length and miniaturized design.

[0130] TTL / |f1|=1.24; where TTL is the distance on the optical axis from the object-side surface S1 of the first lens element L1 to the imaging surface S9 of the imaging lens 100, and f1 is the focal length of the first lens element L1. Satisfying this relationship facilitates correction of aberrations in the optical system.

[0131] (f2 + f3) / CT2 = 0.79; where f2 is the focal length of second lens element L2, f3 is the focal length of third lens element L3, and CT2 is the thickness of second lens element L2 at the optical axis. When this relationship is met, the refractive power of second lens element L2 and third lens element L3 is properly distributed, balancing the aberrations introduced by first lens element L1. This reduces system sensitivity to tolerances and improves imaging quality.

[0132] f23 / f=9.46; where f23 is the combined focal length of the second lens element L2 and the third lens element L3, and f is the effective focal length of the imaging lens 100. When this relationship is satisfied, the refractive powers of the second lens element L2 and the third lens element L3 can be properly distributed, effectively correcting system aberrations.

[0133] R2 / f1 = 4.14; where R2 is the radius of curvature of the image-side surface S2 of the first lens element L1 at the optical axis, and f1 is the focal length of the first lens element L1. When this relationship is satisfied, the image-side surface S2 of the first lens element L1 has an appropriate radius of curvature at the optical axis, which facilitates aberration correction.

[0134] BFL = 14.95; where BFL is the shortest distance between the image-side surface S6 of the third lens element L3 and the imaging surface S9 of the imaging lens 100 parallel to the optical axis, and is measured in mm. Meeting this relationship ensures a sufficient focusing range during system assembly, improving the assembly yield of the lens module. It also enables the imaging lens 100 to have a greater depth of focus, facilitating the acquisition of more object-side depth information.

[0135] TTL / SL=3413.83; where TTL is the distance on the optical axis from the object-side surface S1 of the first lens element L1 to the imaging surface S9 of the imaging lens 100, and SL is the distance from the aperture STO to the maximum effective radius of the object-side surface S1 of the first lens element L1 in a direction parallel to the optical axis.

[0136] ΣET(len) / TTL=0.20; where ΣET(len) is the sum of the thicknesses of the first lens element L1, the second lens element L2, and the third lens element L3 at their maximum effective radius, and TTL is the distance on the optical axis from the object-side surface S1 of the first lens element L1 to the imaging surface S9 of the imaging lens 100.

[0137] ET12 / f=0.17; where ET12 is the total thickness of the first lens element L1 and the second lens element L2 at the maximum effective radius, and f is the effective focal length of the imaging lens 100 .

[0138] When the photosensitive element is disposed on the imaging surface S9 of the imaging lens 100, the relationship is also satisfied: TTL / Imgh=7.82; where TTL is the distance on the optical axis from the object-side surface S1 of the first lens L1 to the imaging surface S9 of the imaging lens 100, and Imgh is half the diagonal length of the effective pixel area of ​​the photosensitive element.

[0139] In addition, the parameters of the imaging lens 100 are given in Tables 1 and 2. The elements from the object side to the image side are arranged in the order of the elements from top to bottom in Table 1. Among them, surface numbers 6 and 7 are the object side surface S1 and image side surface S2 of the first lens L1, respectively, that is, in the same lens, the surface with a smaller surface number is the object side surface, and the surface with a larger surface number is the image side surface. The Y radius in Table 1 is the radius of curvature of the object side surface or image side surface of the corresponding surface number at the optical axis. The first value (absolute value) in the "Thickness" parameter column of the first lens L1 is the thickness of the lens on the optical axis, and the second value is the distance from the image side surface of the lens to the object side surface of the next lens on the optical axis. The value of the aperture ST0 in the "Thickness" parameter column is the distance from the aperture ST0 to the vertex of the object side surface of the next lens (the vertex refers to the intersection of the lens and the optical axis). Here, it is assumed that the direction from the object side surface S1 of the first lens L1 to the image side surface S6 of the third lens L3 is the negative direction of the optical axis. When the "Thickness" value is positive, it means that the aperture ST0 is set to the right of the vertex of the object side surface of the lens (refer to Figure 1 ), if the aperture STO "thickness" value is negative, the aperture STO is on the left side of the vertex of the lens object side. In addition, surface numbers 2 to 4 represent the incident surface G1, reflection surface G2 and exit surface G3 of the prism respectively (see Figure 1), the absolute value of the corresponding "Thickness" parameter is the distance from that surface to the next surface on the optical path. The thickness value for surface number 4 is the distance from exit surface G3 to aperture ST0 on the optical path. Additionally, the surface numbered 1 in the table is a virtual surface used in the design program to simulate the light-emitting surface.

[0140] Table 2 is a table of relevant parameters of the aspheric surface of each lens in Table 1, where K is the cone constant and Ai is the coefficient corresponding to the i-th high-order term in the aspheric surface formula.

[0141] In addition, in the following embodiments, the refractive index and focal length of each lens are values ​​at the reference wavelength. In each embodiment, the calculation results of the relationship are given priority to the optical element parameter table of the corresponding embodiment (such as Table 1 of the first embodiment) and the aspheric coefficient table (such as Table 1 of the first embodiment). Figure 2 ) shall prevail.

[0142] In the first embodiment, the imaging lens 100 has an effective focal length f=17.41 mm, an aperture number FNO=4.9, a field of view FOV=17.06 degrees, and a distance TTL on the optical axis from the object-side surface S1 of the first lens element L1 to the imaging surface S9=20.48 mm.

[0143] Table 1

[0144]

[0145] Table 2

[0146]

[0147] Second embodiment

[0148] refer to Figure 3 In the second embodiment shown, the imaging lens 100 includes, from the object side to the image side, an aperture stop ST0, a first lens element L1 having positive refractive power, a second lens element L2 having negative refractive power, a third lens element L3 having positive refractive power, and an infrared cut-off filter L4. In some embodiments, the imaging lens 100 further includes a prism disposed on the object side of the first lens element L1. Figure 4 1 and 2 are the longitudinal spherical aberration (mm), astigmatism (mm), and distortion (%) of the imaging lens 100 in the second embodiment, wherein the astigmatism and distortion diagrams are data diagrams at a reference wavelength.

[0149] The object-side surface S1 of the first lens L1 is convex along the optical axis, and the image-side surface S2 of the first lens L1 is convex along the optical axis; the object-side surface S1 of the first lens L1 is convex along the circumference, and the image-side surface S2 of the first lens L1 is concave along the circumference. The object-side surface S3 of the second lens L2 is convex along the optical axis, and the image-side surface S4 of the second lens L2 is concave along the optical axis; the object-side surface S3 of the second lens L2 is convex along the circumference, and the image-side surface S4 of the second lens L2 is concave along the circumference. The object-side surface S5 of the third lens L3 is convex along the optical axis, and the image-side surface S6 of the third lens L3 is convex along the optical axis; the object-side surface S5 of the third lens L3 is convex along the circumference, and the image-side surface S6 of the third lens L3 is convex along the circumference.

[0150] The object-side surfaces and image-side surfaces of the first lens L1 , the second lens L2 , and the third lens L3 are all aspherical surfaces.

[0151] In addition, the first lens L1 , the second lens L2 , and the third lens L3 are all made of plastic.

[0152] In the second embodiment, the imaging lens 100 has an effective focal length f=17.40 mm, an aperture number FNO=4.9, a field of view FOV=17.12 degrees, and a distance TTL on the optical axis from the object-side surface S1 of the first lens element L1 to the imaging surface S9=20.43 mm.

[0153] In addition, various parameters of the imaging lens 100 are given in Table 3 and Table 4, and the definitions of the various parameters can be obtained from the first embodiment and are not repeated here.

[0154] Table 3

[0155]

[0156] Table 4

[0157]

[0158]

[0159] Based on the above parameter information, the following data can be derived:

[0160]

[0161] Third embodiment

[0162] refer to Figure 5In the third embodiment shown, the imaging lens 100 includes, from the object side to the image side, an aperture stop ST0, a first lens L1 with positive refractive power, a second lens L2 with negative refractive power, a third lens L3 with negative refractive power, and an infrared cut filter L4. In some embodiments, a prism is further included on the object side of the first lens L1. In addition, Figure 6 1 and 2 are the longitudinal spherical aberration (mm), astigmatism (mm), and distortion (%) of the imaging lens 100 in the third embodiment, wherein the astigmatism and distortion diagrams are data diagrams at a reference wavelength.

[0163] The object-side surface S1 of the first lens L1 is convex along the optical axis, and the image-side surface S2 of the first lens L1 is convex along the optical axis; the object-side surface S1 of the first lens L1 is convex along the circumference, and the image-side surface S2 of the first lens L1 is concave along the circumference. The object-side surface S3 of the second lens L2 is convex along the optical axis, and the image-side surface S4 of the second lens L2 is concave along the optical axis; the object-side surface S3 of the second lens L2 is concave along the circumference, and the image-side surface S4 of the second lens L2 is convex along the circumference. The object-side surface S5 of the third lens L3 is concave along the optical axis, and the image-side surface S6 of the third lens L3 is convex along the optical axis; the object-side surface S5 of the third lens L3 is concave along the circumference, and the image-side surface S6 of the third lens L3 is convex along the circumference.

[0164] The object-side surfaces and image-side surfaces of the first lens L1 , the second lens L2 , and the third lens L3 are all aspherical surfaces.

[0165] In addition, the first lens L1 , the second lens L2 , and the third lens L3 are all made of plastic.

[0166] In the third embodiment, the imaging lens 100 has an effective focal length f=17.50 mm, an aperture number FNO=4.9, a field of view FOV=16.95 degrees, and a distance TTL on the optical axis from the object-side surface S1 of the first lens element L1 to the imaging surface S9=18.94 mm.

[0167] In addition, various parameters of the imaging lens 100 are given in Table 5 and Table 6, and the definitions of the various parameters can be obtained from the first embodiment and are not repeated here.

[0168] Table 5

[0169]

[0170]

[0171] Table 6

[0172]

[0173] Based on the above parameter information, the following data can be derived:

[0174]

[0175] Fourth embodiment

[0176] refer to Figure 7 In the fourth embodiment shown, the imaging lens 100 includes, from the object side to the image side, an aperture stop ST0, a first lens element L1 with negative refractive power, a second lens element L2 with positive refractive power, a third lens element L3 with negative refractive power, and an infrared cut-off filter L4. In some embodiments, the imaging lens 100 further includes a prism disposed on the object side of the first lens element L1. Figure 8 1 and 2 are the longitudinal spherical aberration (mm), astigmatism (mm), and distortion (%) of the imaging lens 100 in the fourth embodiment, where the astigmatism and distortion diagrams are data diagrams at a reference wavelength.

[0177] The object-side surface S1 of the first lens L1 is convex along the optical axis, and the image-side surface S2 of the first lens L1 is concave along the optical axis; the object-side surface S1 of the first lens L1 is convex along the circumference, and the image-side surface S2 of the first lens L1 is concave along the circumference. The object-side surface S3 of the second lens L2 is convex along the optical axis, and the image-side surface S4 of the second lens L2 is convex along the optical axis; the object-side surface S3 of the second lens L2 is convex along the circumference, and the image-side surface S4 of the second lens L2 is convex along the circumference. The object-side surface S5 of the third lens L3 is convex along the optical axis, and the image-side surface S6 of the third lens L3 is concave along the optical axis; the object-side surface S5 of the third lens L3 is convex along the circumference, and the image-side surface S6 of the third lens L3 is concave along the circumference.

[0178] The object-side surfaces and image-side surfaces of the first lens L1 , the second lens L2 , and the third lens L3 are all aspherical surfaces.

[0179] In addition, the first lens L1 , the second lens L2 , and the third lens L3 are all made of plastic.

[0180] In the fourth embodiment, the imaging lens 100 has an effective focal length f=17.45 mm, an aperture number FNO=5.25, a field of view FOV=16.57 degrees, and a distance TTL on the optical axis from the object-side surface S1 of the first lens element L1 to the imaging surface S9=17.69 mm.

[0181] In addition, various parameters of the imaging lens 100 are given in Table 7 and Table 8, and the definitions of the various parameters can be obtained from the first embodiment and are not repeated here.

[0182] Table 7

[0183]

[0184] Table 8

[0185]

[0186] Based on the above parameter information, the following data can be derived:

[0187]

[0188]

[0189] Fifth embodiment

[0190] refer to Figure 9 In the fifth embodiment shown, the imaging lens 100 includes, from the object side to the image side, an aperture stop ST0, a first lens element L1 with negative refractive power, a second lens element L2 with positive refractive power, a third lens element L3 with positive refractive power, and an infrared cutoff filter L4. In some embodiments, the imaging lens 100 further includes a prism disposed on the object side of the first lens element L1. Figure 10 1 and 2 are the longitudinal spherical aberration (mm), astigmatism (mm), and distortion (%) of the imaging lens 100 in the fifth embodiment, where the astigmatism and distortion diagrams are data diagrams at a reference wavelength.

[0191] The object-side surface S1 of the first lens L1 is convex along the optical axis, and the image-side surface S2 of the first lens L1 is concave along the optical axis; the object-side surface S1 of the first lens L1 is convex along the circumference, and the image-side surface S2 of the first lens L1 is concave along the circumference. The object-side surface S3 of the second lens L2 is convex along the optical axis, and the image-side surface S4 of the second lens L2 is concave along the optical axis; the object-side surface S3 of the second lens L2 is convex along the circumference, and the image-side surface S4 of the second lens L2 is convex along the circumference. The object-side surface S5 of the third lens L3 is convex along the optical axis, and the image-side surface S6 of the third lens L3 is concave along the optical axis; the object-side surface S5 of the third lens L3 is convex along the circumference, and the image-side surface S6 of the third lens L3 is concave along the circumference.

[0192] The object-side surfaces and image-side surfaces of the first lens L1 , the second lens L2 , and the third lens L3 are all aspherical surfaces.

[0193] In addition, the first lens L1 , the second lens L2 , and the third lens L3 are all made of plastic.

[0194] In the fifth embodiment, the imaging lens 100 has an effective focal length f=17.40 mm, an aperture number FNO=5.25, a field of view FOV=16.62 degrees, and a distance TTL on the optical axis from the object-side surface S1 of the first lens element L1 to the imaging surface S9=17.67 mm.

[0195] In addition, various parameters of the imaging lens 100 are given in Table 9 and Table 10, and the definitions of the various parameters can be obtained from the first embodiment and are not repeated here.

[0196] Table 9

[0197]

[0198]

[0199] Table 10

[0200]

[0201] Based on the above parameter information, the following data can be derived:

[0202]

[0203] refer to Figure 11 As shown, the imaging lens 100 and the photosensitive element 200 are assembled together to form the camera module 10. The photosensitive element 200 is arranged on the image side of the imaging lens 100. Preferably, the photosensitive element 200 is arranged on the imaging surface S9. The photosensitive element 200 can be a CCD (Charge Coupled Device) or a CMOS (Complementary Metal Oxide Semiconductor). It should be noted that in some embodiments, the imaging lens 100 does not include the infrared cutoff filter L4. In this case, the infrared cutoff filter L4 can be fixedly set with the photosensitive element 200 and set together with the photosensitive element 200 on the image side of the imaging lens 100 during assembly.

[0204] In some embodiments, the distance between the photosensitive element 200 and the imaging lens 100 is fixed, and the camera module 10 is a fixed-focus module. In other embodiments, a voice coil motor is configured on the photosensitive element 200 to enable relative movement of the photosensitive element 200 relative to the lenses in the imaging lens 100. In other embodiments, a fixing member may be provided to secure the aperture ST0, the first lens L1, the second lens L2, and the third lens L3, and a voice coil motor may be configured on the fixing member to drive the aforementioned lenses and the aperture ST0 to move relative to the photosensitive element 200, thereby achieving a focusing function.

[0205] refer to Figure 11 and Figure 12 It should be noted that, according to actual product requirements, the camera module 10 in some embodiments is not provided with a reflector 120 (such as a prism or a plane reflector). In this case, the light carrying the subject information directly enters the lens group (the first lens L1, the second lens L2 and the third lens L3); while in other embodiments, the camera module 10 may be provided with a reflector 120. In this case, the light carrying the subject information enters the lens group after being reflected by the reflector 120.

[0206] In some embodiments, the reflector 120 can be assembled together with the lens assembly to form the imaging lens 100. During assembly, the positions of the reflector 120 and the lens assembly can be calibrated. Therefore, when the imaging lens 100 is subsequently assembled with the photosensitive element 200, the positional relationship between the reflector 120 and the lens assembly can be avoided, reducing the difficulty of subsequent assembly.

[0207] In some embodiments, the imaging lens 100 does not include the reflector 120. In this case, the reflector 120 can be mounted on the object side of the first lens L1 when the imaging lens 100 is assembled with the photosensitive element 200. The reflector 120 reflects light carrying subject information into the lens group.

[0208] refer to Figure 13 The camera module 10 can be applied to an electronic device 20. Specifically, the electronic device 20 is a smartphone, a tablet computer, an electronic watch, a PDA (Personal Digital Assistant), a game console, a PC, etc. By adopting the camera module 10, the electronic device 20 can have a telephoto characteristic while also having a light transmittance that is adapted to the focal length range, thereby improving the dark imaging image of a general telephoto lens and improving the imaging quality during telephoto shooting, thereby having excellent telephoto camera performance. In some embodiments, by providing a reflector, the electronic device 20 will also have a periscope shooting function.

[0209] The technical features of the above-mentioned embodiments can be combined arbitrarily. In order to make the description concise, not all possible combinations of the technical features in the above-mentioned embodiments are described. However, as long as there is no contradiction in the combination of these technical features, they should be considered to be within the scope of this specification.

[0210] The above-described embodiments merely illustrate several implementations of the present invention, and while their descriptions are relatively specific and detailed, they should not be construed as limiting the scope of the patent. It should be noted that a person skilled in the art would be able to make numerous variations and improvements without departing from the spirit of the present invention, all of which fall within the scope of protection of the present invention. Therefore, the scope of protection of the patent for this invention shall be determined by the appended claims.

Claims

1. An imaging lens, characterized in that: The imaging lens is composed of three lenses with refractive power, and includes the following from the object side to the image side: a first lens having refractive power, wherein the object-side surface of the first lens is convex at the optical axis; a second lens having refractive power, wherein the object-side surface of the second lens is convex at the optical axis; a third lens having refractive power, wherein both the object-side surface and the image-side surface of the third lens are aspherical; The imaging lens satisfies the following relationship: ,6.75≤TTL / Imgh<8; Wherein, FNO is the aperture number of the imaging lens, L is the aperture diameter of the first lens, the unit of L is mm, ΣET is the distance from the aperture to the maximum effective radius of the image side surface of the third lens in the direction parallel to the optical axis, EPD is the entrance pupil diameter of the imaging lens, f is the effective focal length of the imaging lens, TTL is the distance from the object side surface of the first lens to the imaging plane of the imaging lens on the optical axis, and Imgh is half the diagonal length of the effective pixel area of ​​the photosensitive element.

2. The imaging lens according to claim 1, wherein: The imaging lens satisfies the relationship: -37<f1 / CT1≤16.34; Wherein, f1 is the focal length of the first lens, and CT1 is the thickness of the first lens at the optical axis.

3. The imaging lens according to claim 1, wherein: The imaging lens satisfies the relationship: 1.0<TTL / |f|<1.2; Wherein, TTL is the distance from the object side surface of the first lens to the imaging surface of the imaging lens on the optical axis, and f is the effective focal length of the imaging lens.

4. The imaging lens according to claim 1, wherein: The imaging lens satisfies the relationship: 0.86≤TTL / |f1|≤2.53; Wherein, TTL is the distance from the object side surface of the first lens to the imaging surface of the imaging lens on the optical axis, and f1 is the focal length of the first lens.

5. The imaging lens according to claim 1, wherein: The imaging lens satisfies the relationship: -585<(f2+f3) / CT2<30; Wherein, f2 is the focal length of the second lens, f3 is the focal length of the third lens, and CT2 is the thickness of the second lens at the optical axis.

6. The imaging lens according to claim 1, wherein: The imaging lens satisfies the relationship: -0.8<f23 / f<10; Wherein, f23 is the combined focal length of the second lens and the third lens, and f is the effective focal length of the imaging lens.

7. The imaging lens according to claim 1, wherein: The imaging lens satisfies the relationship: 0.24≤R2 / f1<5; Wherein, R2 is the curvature radius of the image side surface of the first lens at the optical axis, and f1 is the focal length of the first lens.

8. The imaging lens according to claim 1, wherein: The imaging lens satisfies the relationship: 11<BFL<16; Wherein, BFL is the distance from the vertex of the image-side surface of the third lens to the imaging plane of the imaging lens in a direction parallel to the optical axis, and the unit of BFL is mm.

9. The imaging lens according to claim 1, wherein: The imaging lens satisfies the relationship: 91<TTL / SL<3450; Wherein, TTL is the distance from the objective side of the first lens to the imaging surface of the imaging lens on the optical axis, and SL is the distance from the aperture to the maximum effective radius of the objective side of the first lens parallel to the optical axis.

10. The imaging lens according to claim 1, wherein: The imaging lens satisfies the relationship: 0.13<ΣET(len) / TTL<0.25; Wherein, ΣET(len) is the sum of the thicknesses of the first lens, the second lens, and the third lens at the maximum effective radius, and TTL is the distance from the object-side surface of the first lens to the imaging plane of the imaging lens on the optical axis.

11. The imaging lens according to claim 1, wherein: The imaging lens satisfies the relationship: 0.06<ET12 / f<0.2; Wherein, ET12 is the sum of the thicknesses of the first lens and the second lens at the maximum effective radius, and f is the effective focal length of the imaging lens.

12. The imaging lens according to any one of claims 1 to 11, wherein: It also includes a reflector, which is arranged on the object side of the first lens. The light carrying the subject information can be reflected by the reflector to the first lens.

13. A camera module, characterized in that: The imaging lens comprises a photosensitive element and the imaging lens according to any one of claims 1 to 12, wherein the photosensitive element is arranged on the image side of the imaging lens.

14. The camera module according to claim 13, wherein: The photosensitive element is arranged on the imaging surface of the imaging lens, and the camera module satisfies the relationship: 6.75≤TTL / Imgh<8; Wherein, TTL is the distance from the object side of the first lens to the imaging surface of the imaging lens on the optical axis, and Imgh is half of the diagonal length of the effective pixel area of ​​the photosensitive element.

15. An electronic device, characterized in that: Including the camera module described in claim 13 or 14.

Images