Optical systems, camera modules and electronic equipment

Abstract

The present invention relates to an optical system, a camera module and an electronic device. The optical system includes, from the object side to the image side, in sequence: a first lens with positive refractive power, whose object side and image side are both convex at the paraxial position; a second lens, a third lens and a fourth lens with refractive power; a fifth lens with refractive power, whose object side is convex at the paraxial position and whose image side is concave at the paraxial position; a sixth lens with refractive power, whose object side is concave at the paraxial position; a seventh lens with refractive power; the optical system satisfies the relationship: 16mm≤SDL1*FNO≤25mm; SDL1 is the maximum effective aperture of the object side of the first lens, and FNO is the aperture number of the optical system. While suppressing stray light and system aberrations, the above optical system can also avoid excessive interception of the central field of view light, resulting in insufficient system light flux, so that the optical system has good imaging brightness, thereby improving imaging clarity.

Description

Technical Field

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

[0002] Since camera lenses have been applied to electronic devices such as smartphones and tablets, the shooting performance of the devices has also undergone tremendous changes as users' demand for high-quality photography has increased. Generally speaking, camera lenses with a seven-element structure have a more obvious advantage in obtaining high-resolution imaging due to the reasonable number of lenses and large design freedom. Therefore, this type of camera lens is often used in high-end mobile electronic products to improve the image quality, resolution and clarity of the shooting.

[0003] When designing a camera lens, it is necessary to consider various factors such as various aberrations, stray light, and image brightness of the lens in order to suppress the aberrations and stray light of the system as much as possible, while preventing the light transmittance from being too low. For a camera lens with a seven-piece structure, it is also necessary to specially design its multiple lenses to regulate the incident light, and these various considerations often make the design of the camera lens too difficult. In particular, it is difficult to achieve a good coordination in the design of suppressing aberrations and maintaining a good light transmittance, which often makes it difficult to effectively improve the imaging clarity of the system. Summary of the invention

[0004] Based on this, it is necessary to provide an optical system, a camera module and an electronic device to address the problem of how to coordinate the suppression of aberrations with the maintenance of a good amount of light to improve imaging clarity.

[0005] An optical system, comprising, from the object side to the image side, the following:

[0006] A first lens having positive refractive power, wherein the object side surface of the first lens is convex at the paraxial position, and the image side surface of the first lens is convex at the paraxial position;

[0007] a second lens having refractive power;

[0008] a third lens having refractive power;

[0009] Aperture;

[0010] a fourth lens having a refractive power;

[0011] a fifth lens having a refractive power, wherein the object side surface of the fifth lens is a convex surface at the paraxial position, and the image side surface of the fifth lens is a concave surface at the paraxial position;

[0012] a sixth lens having refractive power, wherein the object side surface of the sixth lens is concave at the paraxial position;

[0013] a seventh lens having refractive power;

[0014] The optical system satisfies the relationship:

[0015] 16mm≤SDL1*FNO≤25mm;

[0016] Wherein, SDL1 is the maximum effective aperture of the object side of the first lens, and FNO is the aperture number of the optical system.

[0017] By adopting the above lens design and making the optical system satisfy the above relationship, the ratio of the maximum effective aperture of the object side of the first lens and the system aperture number can be reasonably controlled, so that the aperture of the aperture stop and the effective aperture of the first lens are well adapted to prevent the effective aperture of the first lens from being too small and the aperture of the aperture stop from being too large, thereby avoiding excessive adjustment of the incident light between the two and generating too much stray light; at the same time, it can also prevent the effective aperture of the first lens from being too large and the aperture of the aperture stop from being too small, thereby avoiding the ineffective light of the outer field of view from passing through the aperture stop along with the light of the central field of view to be incident on the imaging surface of the system, thereby effectively and reasonably intercepting the edge light of the outer field of view, suppressing the generation of aberrations such as spherical aberration and field curvature, and thus effectively improving the clarity of the imaging picture. By satisfying the above constraints on the effective aperture and aperture number of the first lens, while suppressing stray light and system aberrations, it is also possible to avoid excessive interception of the central field of view light, which leads to insufficient system light throughput, and promote the system to achieve good coordination between suppressing aberrations and maintaining good light throughput, so that the optical system has good imaging brightness, which can also improve imaging clarity. When SDL1*FNO<16mm, it will be unfavorable for the convergence of incident light on the imaging surface, and a large amount of stray light will be generated, resulting in a decrease in shooting quality; when SDL1*FNO>25mm, the effective aperture of the object side of the first lens will be too large compared to the aperture of the aperture stop, and the edge light will be difficult to be reasonably intercepted, resulting in an increase in the field curvature of the system and an increase in the distortion of the edge field of view.

[0018] On the other hand, in the above-mentioned optical system, the aperture is placed in the optical system. When the above-mentioned design is met, the aperture can suppress the passage of ineffective light in the outer field of view while avoiding the loss of excessive light in the outer field of view, and can better maintain the imaging brightness of the edge field of view and prevent the generation of dark corners.

[0019] In one embodiment, the optical system satisfies the relationship:

[0020] 1≤ETL5 / CTL5≤3;

[0021] Among them, ETL5 is the distance from the maximum effective aperture of the object side of the fifth lens to the maximum effective aperture of the image side in the direction of the optical axis, and CTL5 is the thickness of the fifth lens at the optical axis. When the above relationship is met, the central structure of the fifth lens has a thinner design compared to the edge structure, which can effectively balance the optical path difference of the light of the central field of view and the edge field of view in the optical system, prevent the optical path difference from being too large, and enable the light of the central field of view and the edge field of view to converge near the imaging surface of the system, thereby realizing the function of correcting the field curvature. In addition, the fifth lens that meets the above relationship can also prevent the center from being too thin or too thick compared to the edge, thereby meeting the precision requirements of production and processing and ensuring the molding yield. In the optical system of the present application, if the center of the fifth lens is too thin or too thick compared to the edge, it will make it difficult for the central light and the edge light to converge near the imaging surface of the system, resulting in excessive field curvature. For example, when ETL5 / CTL5 is less than 1, the center of the fifth lens will be too thick relative to the edge, resulting in excessive image field curvature; and when ETL5 / CTL5 is greater than 3, the center of the lens will be too thin, which will not only cause severe field curvature but also reduce the molding yield of the lens.

[0022] In one embodiment, the optical system satisfies the relationship:

[0023] 12≤FOV / AngleS1≤25;

[0024] Among them, FOV is the maximum field of view angle of the optical system, and AngleS1 is the maximum angle between the tangent plane of the object side of the first lens and the plane perpendicular to the optical axis. The maximum inclination angle of the object side of the first lens and the field of view angle of the system play a decisive role in the entire optical system receiving the object space light information. By satisfying the constraints of the above-mentioned relationship conditions, the two can enable a wide range of light information to enter the optical system, thereby satisfying the large field of view shooting effect. If FOV / AngleS1<12, the field of view angle of the system will be too small, and it will be difficult to achieve a large field of view shooting effect; if FOV / AngleS1>25, the inclination angle of the first incident surface of the system (the object side of the first lens) will be too large, causing secondary reflection and causing ghost images, and at the same time it will increase the process difficulty, which is not conducive to the production and processing of the lens.

[0025] In one embodiment, the optical system satisfies the relationship:

[0026] FNO / TTL≤0.2mm -1 ;

[0027] Wherein, TTL is the distance from the object side of the first lens to the imaging surface of the optical system on the optical axis. Compared with ordinary cameras, periscope cameras have the problem of low light throughput. When the above relationship is met, the optical system can take into account both the telephoto performance and miniaturization design requirements of the optical system, and provide sufficient light throughput for video shooting to meet the needs of high-quality and high-definition shooting. When Fno / TTL>0.2mm -1 When the system is miniaturized, it will cause insufficient light transmission and reduce the clarity of the captured image.

[0028] In one embodiment, the optical system satisfies the relationship:

[0029] 12mm / rad≤SDL1 / RAD(FOV)≤25mm / rad;

[0030] Among them, RAD(FOV) is the radian value of the maximum field of view angle of the optical system. In this optical system, the maximum effective aperture of the first lens determines the size of the field of view angle of the system, and the reasonable combination of the two can ensure that a wide range of light information enters the optical system for imaging. When SDL1 / RAD(fov)>25, the field of view angle of the system will be small, and it will be difficult for the optical system to achieve a large field of view shooting effect; and when SDL1 / RAD(fov)<12, the effective aperture of the first lens is too small and the field of view angle is too large, and the two cannot form a good fit, which will cause serious imaging distortion and distorted imaging of the external field of view.

[0031] In one embodiment, the optical system satisfies the relationship:

[0032] 0.5≤TTL / f≤1.5;

[0033] Wherein, TTL is the distance from the object side of the first lens to the imaging surface of the optical system on the optical axis, and f is the effective focal length of the optical system. When the above relationship is satisfied, the focal length and the total optical length of the optical system can be reasonably controlled, which can not only realize the miniaturization design of the optical system, but also promote the better convergence of light on the imaging surface. When TTL / f≤0.5, the optical length of the system is too short, resulting in increased sensitivity of the system, and is not conducive to the convergence of light on the imaging surface; when TTL / f≥1.5, the optical length of the system is too long, and the effective focal length of the system is too short, and the two cannot be adapted, resulting in the main light of the external field of view entering the imaging surface at an angle that is too large, and the light of the external field of view cannot be imaged on the photosensitive surface, resulting in incomplete imaging information.

[0034] In one embodiment, the optical system satisfies the relationship:

[0035] 0.3≤Imgh / TTL≤0.5;

[0036] Among them, Imgh is the image height corresponding to the maximum field of view angle of the optical system, and TTL is the distance from the object side of the first lens to the imaging surface of the optical system on the optical axis. When the above relationship is satisfied, the optical system can take into account both miniaturization and high-definition shooting. When Imgh / TTL>0.5, it is difficult for the system to achieve miniaturization while ensuring high-definition imaging effects; when Imgh / TTL<0.3, the system length will be too long, resulting in the need to increase the assembly space, which is not conducive to miniaturization design.

[0037] In one embodiment, the optical system satisfies the relationship:

[0038] BFL / TTL>0.2;

[0039] Among them, BFL is the minimum value of the distance from the image side of the seventh lens to the imaging surface of the optical system in the direction of the optical axis, and TTL is the distance from the object side of the first lens to the imaging surface of the optical system on the optical axis. When the above relationship is met, the optical system can ensure sufficient focusing range while meeting the miniaturization design, that is, ensuring that the lens and the image sensor have sufficient adjustment space during the assembly process, thereby improving the assembly yield of the lens module. In addition, the optical system that meets the above relationship will also have a larger depth of focus, which is conducive to obtaining more depth information on the object side. When BFL / TTL is less than 0.2, the processing tolerance allowed by the module during the assembly process is too small, resulting in too low a yield and increased difficulty in the production process. At the same time, it cannot ensure that the optical system has sufficient depth of focus, resulting in poor imaging quality.

[0040] In one embodiment, the optical system satisfies the relationship:

[0041] 0.8≤SDL1 / Imgh≤1.2;

[0042] Among them, Imgh is the image height corresponding to the maximum field angle of the optical system. The size of the maximum effective aperture of the first lens determines the amount of light transmitted by the entire optical system, and the size of the photosensitive surface determines the image clarity and pixel size of the entire camera system. The reasonable combination of the two can ensure the appropriate imaging brightness and image clarity. When SDL1 / Imgh>1.2, it will cause overexposure and excessive brightness of the image, affecting the image quality; and when SDL1 / Imgh<0.8, it will cause insufficient light transmission and insufficient relative brightness of light, which will cause a decrease in the sensitivity of the image.

[0043] In one embodiment, the optical system satisfies the relationship:

[0044] 10mm 2 ≤(R9*R10) / (R9 / R10)≤25mm2 ;

[0045] Wherein, R9 is the radius of curvature of the object side of the fifth lens at the optical axis, and R10 is the radius of curvature of the image side of the fifth lens at the optical axis. When the above relationship is satisfied, the radii of curvature of the object side and the image side of the fifth lens can be reasonably configured, which can balance the optical path difference between the edge light and the paraxial light of the optical system, reasonably correct the field curvature and astigmatism, and reduce the sensitivity of the system and improve the assembly stability. When (R9*R10)+(R9 / R10)>25, the field curvature of the optical system will be too large; when (R9*R10)+(R9 / R10)<10, the sensitivity of the system will increase, resulting in a decrease in production yield.

[0046] In one embodiment, the optical system includes an optical path deflecting element disposed on the object side of the first lens, and the optical path deflecting element is used to reflect incident light to the first lens. By providing the optical path deflecting element, the optical system can form a periscope optical imaging system when applied to an electronic device, thereby effectively reducing the size of the system in the direction of incident light, thereby facilitating the ultra-thin design of the device.

[0047] A camera module comprises an image sensor and any one of the above optical systems, wherein the image sensor is arranged on the image side of the optical system. By adopting the above optical system, the camera module can suppress stray light and system aberrations when shooting, and can also avoid excessive interception of central field light, which leads to insufficient light flux of the system, so that the system can achieve good coordination between suppressing aberrations and maintaining good light flux, thereby having good image brightness during shooting, thereby improving image clarity.

[0048] An electronic device includes the above-mentioned camera module. By adopting the above-mentioned camera module, the imaging picture of the electronic device during shooting can not only effectively suppress stray light and aberration, but also maintain good imaging brightness, so that the electronic device has excellent shooting performance. BRIEF DESCRIPTION OF THE DRAWINGS

[0049] Figure 1 A schematic diagram of the structure of an optical system provided in the first embodiment of the present application;

[0050] Figure 2 including a longitudinal spherical aberration diagram, an astigmatism diagram and a distortion diagram of the optical system in the first embodiment;

[0051] Figure 3 A schematic diagram of the structure of an optical system provided in the second embodiment of the present application;

[0052] Figure 4 including a longitudinal spherical aberration diagram, an astigmatism diagram and a distortion diagram of the optical system in the second embodiment;

[0053] Figure 5 A schematic diagram of the structure of an optical system provided in the third embodiment of the present application;

[0054] Figure 6 including a longitudinal spherical aberration diagram, an astigmatism diagram and a distortion diagram of the optical system in the third embodiment;

[0055] Figure 7 A schematic diagram of the structure of an optical system provided in a fourth embodiment of the present application;

[0056] Figure 8 including a longitudinal spherical aberration diagram, an astigmatism diagram and a distortion diagram of the optical system in the fourth embodiment;

[0057] Fig. 9 A schematic diagram of the structure of an optical system provided in a fifth embodiment of the present application;

[0058] Fig.10 including a longitudinal spherical aberration diagram, an astigmatism diagram and a distortion diagram of the optical system in the fifth embodiment;

[0059] Fig.11 A schematic diagram of the structure of an optical system provided in a sixth embodiment of the present application;

[0060] Fig.12 including a longitudinal spherical aberration diagram, an astigmatism diagram and a distortion diagram of the optical system in the sixth embodiment;

[0061] Fig.13 A schematic diagram of a camera module provided in one embodiment of the present application;

[0062] Fig.14 A schematic diagram of an electronic device provided in one embodiment of the present application;

[0063] Fig.15 AngleS1 of the object-side surface of the first lens in one embodiment of the present application is an example. DETAILED DESCRIPTION

[0064] In order to make the above-mentioned objects, features and advantages of the present invention more obvious and easy to understand, the specific embodiments of the present invention are described in detail below in conjunction with the accompanying drawings. In the following description, many specific details are set forth to facilitate a full understanding of the present invention. However, the present invention can be implemented in many other ways different from those described herein, and those skilled in the art can make similar improvements without violating the connotation of the present invention, so the present invention is not limited by the specific embodiments disclosed below.

[0065] In the description of the present invention, it should be understood that the terms "center", "longitudinal", "lateral", "length", "width", "thickness", "up", "down", "front", "back", "left", "right", "vertical", "horizontal", "top", "bottom", "inside", "outside", "clockwise", "counterclockwise", "axial", "radial", "circumferential" and the like indicate orientations or positional relationships based on the orientations or positional relationships shown in the accompanying drawings, and are only for the convenience of describing the present invention and simplifying the description, and do not indicate or imply that the referred device or element must have a specific orientation, be constructed and operated in a specific orientation, and therefore should not be understood as limiting the present invention.

[0066] In addition, the terms "first" and "second" are used for descriptive purposes only and should not be understood as indicating or implying relative importance or implicitly indicating the number of the indicated technical features. Therefore, the features defined as "first" and "second" may explicitly or implicitly include at least one of the features. In the description of the present invention, the meaning of "plurality" is at least two, such as two, three, etc., unless otherwise clearly and specifically defined.

[0067] In the present invention, unless otherwise clearly specified and limited, the terms "installed", "connected", "connected", "fixed" and the like should be understood in a broad sense, for example, it can be a fixed connection, a detachable connection, or an integral connection; it can be a mechanical connection or an electrical connection; it can be a direct connection or an indirect connection through an intermediate medium, it can be the internal connection of two elements or the interaction relationship between two elements, unless otherwise clearly defined. For ordinary technicians in this field, the specific meanings of the above terms in the present invention can be understood according to specific circumstances.

[0068] In the present invention, unless otherwise clearly specified and limited, a first feature being "above" or "below" a second feature may mean that the first and second features are in direct contact, or the first and second features are in indirect contact through an intermediate medium. Moreover, a first feature being "above", "above" or "above" a second feature may mean that the first feature is directly above or obliquely above the second feature, or simply means that the first feature is higher in level than the second feature. A first feature being "below", "below" or "below" a second feature may mean that the first feature is directly below or obliquely below the second feature, or simply means that the first feature is lower in level than the second feature.

[0069] It should be noted that when an element is referred to as being "fixed to" or "disposed on" another element, it may be directly on the other element or there may be a central element. When an element is considered to be "connected to" another element, it may be directly connected to the other element or there may be a central element at the same time. The terms "vertical", "horizontal", "upper", "lower", "left", "right" and similar expressions used herein are for illustrative purposes only and are not intended to be the only implementation method.

[0070] refer to Figure 1 In the embodiment of the present application, the optical system 10 includes, from the object side to the image side, a first lens L1, a second lens L2, a third lens L3, an aperture (not shown), a fourth lens L4, a fifth lens L5, a sixth lens L6 and a seventh lens L7, wherein the first lens L1 has a positive refractive power. The lenses in the optical system 10 are coaxially arranged, that is, the optical axes of the lenses are all located on the same straight line, which can be called the optical axis of the optical system 10.

[0071] The first lens L1 includes an object-side surface S1 and an image-side surface S2, the second lens L2 includes an object-side surface S3 and an image-side surface S4, the third lens L3 includes an object-side surface S5 and an image-side surface S6, the fourth lens L4 includes an object-side surface S7 and an image-side surface S8, the fifth lens L5 includes an object-side surface S9 and an image-side surface S10, the sixth lens L6 includes an object-side surface S11 and an image-side surface S12, and the seventh lens L7 includes an object-side surface S13 and an image-side surface S14. In addition, the optical system 10 also has an imaging surface S15, and the imaging surface S15 is located on the image side of the seventh lens L7. Generally, the imaging surface S15 of the optical system 10 coincides with the photosensitive surface of the image sensor. For ease of understanding, the imaging surface S15 can be regarded as the photosensitive surface of the photosensitive element.

[0072] The object-side surface S1 of the first lens L1 is convex at the paraxial position, and the image-side surface S2 is convex at the paraxial position; the object-side surface S9 of the fifth lens L5 is convex at the paraxial position, and the image-side surface S10 is concave at the paraxial position; the object-side surface S11 of the sixth lens L6 is concave at the paraxial position.

[0073] In some embodiments, the object side and image side of the first lens L1 to the seventh lens L7 are all aspherical. The aspherical surface setting can further help the optical system 10 eliminate aberrations and solve the problem of field of view distortion. It is also conducive to the miniaturization design of the optical system 10, so that the optical system 10 can have excellent optical effects while maintaining a miniaturized design. Of course, in other embodiments, the object side of any one of the first lens L1 to the seventh lens L7 can be a spherical surface or an aspherical surface; the image side of any one of the first lens L1 to the seventh lens L7 can be a spherical surface or an aspherical surface. The coordination of the spherical surface and the aspherical surface can also effectively eliminate the aberration problem, so that the optical system 10 has an excellent imaging effect, while improving the flexibility of lens design and assembly. In particular, when the seventh lens L7 is an aspherical lens, it will be beneficial to finally correct the aberrations generated by the front lenses, thereby improving the imaging quality. It should be noted that the shape of the spherical or aspherical surface is not limited to the shape of the spherical or aspherical surface shown in the accompanying drawings. The accompanying drawings are only for example reference and are not strictly drawn to scale.

[0074] The calculation of the aspheric surface can refer to the aspheric surface formula:

[0075]

[0076] Among them, Z is the distance from the corresponding point on the aspherical surface to the plane tangent to the surface vertex, r is the distance from the corresponding point on the aspherical surface to the optical axis, c is the curvature of the aspherical vertex, k is the cone coefficient, and Ai is the coefficient corresponding to the i-th order high-order term in the aspherical surface shape formula.

[0077] On the other hand, in some embodiments, when the object side or image side of a lens is an aspheric surface, the surface may be a structure that is convex as a whole or concave as a whole. Alternatively, the surface may also be designed to have a structure with an inflection point, in which case the surface shape of the surface from the center to the edge will change, for example, the surface is convex at the center and concave at the edge. It should be noted that when the embodiments of the present application describe a side of a lens as a convex surface at the optical axis (the central area of ​​the side), it can be understood that the area of ​​the side of the lens near the optical axis is convex, so it can also be considered that the side is convex at the near axis; when describing a side of the lens as a concave surface at the circumference, it can be understood that the area of ​​the side near the maximum effective aperture is concave. For example, when the side is convex at the near axis and is also convex at the circumference, the shape of the side from the center (optical axis) to the edge direction can be a pure convex surface; or it first transitions from the convex shape of the center to the concave shape, and then becomes convex when it is close to the maximum effective aperture. 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 are not fully reflected, but other situations can be deduced based on the above examples and should also be regarded as the content recorded in this application.

[0078] In some embodiments, the material of each lens in the optical system 10 is plastic. Of course, the material of each lens in some embodiments can also be glass. Plastic lenses can reduce the weight of the optical system 10 and reduce production costs, while glass lenses can withstand higher temperatures and have excellent optical effects. In other embodiments, the material of the first lens L1 is glass, and the materials of the second lens L2 to the seventh lens L7 are all plastic. At this time, since the material of the lens located on the object side in the optical system 10 is glass, these glass lenses located on the object side have a good tolerance effect on extreme environments and are not easily affected by the object side environment and aging, etc., so when the optical system 10 is in an extreme environment such as exposure to high temperature, this structure can better balance the optical performance and cost of the system. Of course, the lens material configuration relationship in the optical system 10 is not limited to the above embodiments. The material of any lens can be plastic or glass, and the specific design can be determined according to actual needs.

[0079] In some embodiments, the optical system 10 includes an infrared cut-off filter 110, which is disposed on the image side of the seventh lens L7 and is fixedly disposed relative to each lens in the optical system 10. The infrared cut-off filter 110 is used to filter out infrared light to prevent infrared light from reaching the imaging surface S15 of the system, thereby preventing infrared light from interfering with normal imaging. The infrared cut-off filter 110 can be assembled together with each lens as a part of the optical system 10. In other embodiments, the infrared cut-off filter 110 does not belong to the components of the optical system 10. In this case, the infrared cut-off filter 110 can be installed between the optical system 10 and the photosensitive element when the optical system 10 and the photosensitive element are assembled into a camera module. In some embodiments, the infrared cut-off filter 110 can also be disposed on the object side of the first lens L1. In addition, in some embodiments, the function of filtering out infrared light can also be achieved by providing a filter coating on at least one lens from the first lens L1 to the seventh lens L7.

[0080] In some embodiments, the optical system 10 further includes an optical path refraction element P1 disposed on the object side of the first lens L1, and the optical path refraction element P1 is used to reflect the incident light to the first lens L1. The optical path refraction element P1 can be an element such as a prism that can fold the incident light path of the optical system 10. By providing the optical path refraction element P1, the optical system 10 can form a periscope optical imaging system when applied to an electronic device, thereby effectively reducing the size of the system in the direction of incident light, thereby facilitating the ultra-thin design of the device.

[0081] In the embodiment of the present application, the optical system 10 satisfies the relationship:

[0082] 16mm≤SDL1*FNO≤25mm;

[0083] Wherein, SDL1 is the maximum effective aperture of the object-side surface S1 of the first lens L1 , and FNO is the aperture number of the optical system 10 .

[0084] The optical system 10 can reasonably control the ratio between the maximum effective aperture of the object side S1 of the first lens L1 and the aperture number of the system, so that the aperture of the aperture stop and the effective aperture of the first lens L1 are well matched, and the effective aperture of the first lens L1 is prevented from being too small and the aperture of the aperture stop is too large, so as to avoid excessive adjustment of the incident light between the two and generating too much stray light; at the same time, it can also prevent the effective aperture of the first lens L1 from being too large and the aperture of the aperture stop from being too small, so as to avoid the ineffective light of the outer field of view from passing through the aperture stop along with the light of the central field of view to the imaging surface S15 of the system, so as to effectively and reasonably intercept the edge light of the outer field of view, suppress the generation of aberrations such as spherical aberration and field curvature, and thus effectively improve the clarity of the imaging picture. Specifically, SDL1*FNO in some embodiments can be 17.9mm, 18mm, 18.3mm, 18.6mm, 19mm, 19.5mm, 20mm, 20.3mm, 20.5mm or 20.7mm. By satisfying the above constraints on the effective aperture and aperture number of the first lens L1, while suppressing stray light and system aberrations, it is also possible to avoid excessive interception of the central field of view light and insufficient system light flux, so that the system can be well coordinated between suppressing aberrations and maintaining good light flux, so that the optical system 10 has good imaging brightness, thereby improving imaging clarity. When SDL1*FNO<16mm, it will be unfavorable for the convergence of incident light on the imaging surface, and a large amount of stray light will be generated, resulting in a decrease in shooting quality; when SDL1*FNO>25mm, the effective aperture of the object side S1 of the first lens L1 will be too large compared to the aperture of the aperture stop, and the edge light will be difficult to be reasonably intercepted, resulting in increased field curvature of the system and increased distortion of the edge field of view.

[0085] On the other hand, in the optical system 10 of the present application, the diaphragm is placed in the optical system 10 as an aperture diaphragm. While suppressing the passage of ineffective light in the outer field of view, the diaphragm can also avoid excessive loss of light in the outer field of view, and can better maintain the imaging brightness of the edge field of view and prevent the generation of dark corners.

[0086] In addition, in some embodiments, the optical system 10 further satisfies at least one of the following relationships, and when any of the relationships is satisfied, corresponding effects can be achieved:

[0087] 1≤ETL5 / CTL5≤3; wherein, ETL5 is the distance from the maximum effective aperture of the object side S9 of the fifth lens L5 to the maximum effective aperture of the image side S10 in the direction of the optical axis, or can also be called the edge thickness of the fifth lens L5, and CTL5 is the thickness of the fifth lens L5 at the optical axis. Specifically, ETL5 / CTL5 in some embodiments can be 1, 1.05, 1.1, 1.2, 1.3, 1.4, 1.5, 1.6, 1.65 or 1.7. When the above relationship is met, the central structure of the fifth lens L5 has a thinner design than the edge structure, which can effectively balance the optical path difference of the light of the central field of view and the edge field of view in the optical system 10, prevent the optical path difference from being too large, and enable the light of the central field of view and the edge field of view to converge near the imaging surface of the system, thereby realizing the function of correcting the field curvature. In addition, the fifth lens L5 that meets the above relationship can also prevent the center from being too thin or too thick compared to the edge, thereby meeting the precision requirements of production and processing and ensuring the molding yield. In the optical system 10 of the present application, if the center of the fifth lens L5 is too thin or too thick compared to the edge, it will make it difficult for the central light and the edge light to converge near the imaging surface of the system, resulting in excessive field curvature. For example, when ETL5 / CTL5<1, the center of the fifth lens L5 will be too thick relative to the edge, resulting in excessive field curvature of the image plane; and when ETL5 / CTL5>3, the center of the lens will be too thin, which will not only cause severe field curvature, but also reduce the molding yield of the lens.

[0088] 12≤FOV / AngleS1≤25; wherein FOV is the maximum field angle of the optical system 10, and AngleS1 is the maximum angle between the tangent plane of the object side surface S1 of the first lens L1 and the plane perpendicular to the optical axis (refer to Fig.15 ). refer to Fig.15The object side surface S1 of the first lens L1 is a curved surface. Theoretically, it has countless non-parallel facets. The corresponding area of ​​the object side surface S1 and its corresponding facet intersect at point A. Theoretically, point A can be in any area of ​​the object side surface S1 of the first lens L1, and is not limited to the maximum effective aperture of the surface. As long as the angle between the facet of point A and the plane perpendicular to the optical axis is the largest compared to the angles at other places, the angle of this point can be used as AngleS1. Specifically, FOV / AngleS1 in some embodiments can be 0.42, 0.45, 0.48, 0.5, 0.53, 0.55, 0.58 or 0.6. The maximum tilt angle of the object side surface S1 of the first lens L1 and the field of view angle of the system play a decisive role in the entire optical system 10 receiving the object space light information. By satisfying the constraints of the above-mentioned relationship conditions, the two can enable a wide range of light information to enter the optical system 10, thereby satisfying the large field of view shooting effect. If FOV / AngleS1 is less than 12, the field of view of the system will be too small, making it difficult to achieve a wide field of view shooting effect; if FOV / AngleS1 is greater than 25, the inclination angle of the first incident surface of the system (the object side surface S1 of the first lens L1) will be too large, causing secondary reflection and resulting in ghost images. At the same time, it will also increase the difficulty of the process, which is not conducive to the production and processing of the lens.

[0089] FNO / TTL≤0.2mm -1 ; Wherein, TTL is the distance between the object side surface S1 of the first lens L1 and the imaging surface of the optical system 10 on the optical axis. Specifically, FNO / TTL in some embodiments may be 0.16 mm -1 、0.162mm -1 , 0.165mm -1 、0.168mm -1 or 0.17mm -1 Compared with ordinary cameras, periscope cameras have a problem of low light transmission. When the above relationship is met, the optical system 10 can take into account the telephoto performance and miniaturization design requirements of the optical system 10 at the same time, and provide sufficient light transmission for video shooting to meet the needs of high-quality and high-definition shooting. When Fno / TTL>0.2mm -1 When the system is miniaturized, it will cause insufficient light transmission and reduce the clarity of the captured image.

[0090] 12mm / rad≤SDL1 / RAD(FOV)≤25mm / rad; wherein RAD(FOV) is the radian value of the maximum field of view angle of the optical system 10. In the optical system 10, the maximum effective aperture of the first lens L1 determines the size of the field of view angle of the system, and the reasonable combination of the two can ensure that a wide range of light information enters the optical system 10 for imaging. Specifically, SDL1 / RAD(FOV) in some embodiments can be 15.6, 15.8, 16, 17, 18, 19, 19.5, 19.7 or 20, and the numerical unit is mm / rad. When SDL1 / RAD(fov)>25, the field of view angle of the system will be small, and it will be difficult for the optical system 10 to achieve a large field of view shooting effect; and when SDL1 / RAD(fov)<12, the effective aperture of the first lens L1 is too small and the field of view angle is too large, and the two cannot form a good fit, which will cause serious imaging distortion, and the imaging of the external field of view will be distorted.

[0091] 0.5≤TTL / f≤1.5; wherein TTL is the distance from the object side surface S1 of the first lens L1 to the imaging surface of the optical system 10 on the optical axis, and f is the effective focal length of the optical system 10. Specifically, TTL / f in some embodiments may be 0.95, 0.97, 0.98, 1, 1.01 or 1.02. When the above relationship is satisfied, the focal length and the total optical length of the optical system 10 can be reasonably controlled, which can not only realize the miniaturization design of the optical system 10, but also promote the better convergence of light on the imaging surface. When TTL / f≤0.5, the optical length of the system is too short, resulting in increased sensitivity of the system, and is also not conducive to the convergence of light on the imaging surface; when TTL / f≥1.5, the optical length of the system is too long, and the effective focal length of the system is too short, and the two cannot be adapted, resulting in the angle of the main light of the external field of view entering the imaging surface being too large, and the light of the external field of view cannot be imaged on the photosensitive surface, resulting in incomplete imaging information.

[0092] 0.3≤Imgh / TTL≤0.5; wherein Imgh is the image height corresponding to the maximum field angle of the optical system 10, and TTL is the distance from the object side surface S1 of the first lens L1 to the imaging surface of the optical system 10 on the optical axis. Specifically, Imgh / TTL in some embodiments may be 0.37, 0.38, 0.39, 0.4 or 0.41. When the above relationship is satisfied, the optical system 10 can take into account both miniaturization and high-definition shooting. When Imgh / TTL>0.5, it is difficult to ensure high-definition imaging effects while achieving miniaturization; when Imgh / TTL<0.3, the system length will be too long, resulting in the need to increase the assembly space, which is not conducive to miniaturization design.

[0093] BFL / TTL>0.2; wherein, BFL is the minimum value of the image side surface S14 of the seventh lens L7 to the imaging surface of the optical system 10 in the direction of the optical axis, and TTL is the distance from the object side surface S1 of the first lens L1 to the imaging surface of the optical system 10 on the optical axis. Specifically, BFL / TTL in some embodiments may be 0.34, 0.36, 0.38, 0.4, 0.41, 0.42 or 0.43. When the above relationship is satisfied, the optical system 10 can ensure sufficient focusing range while meeting the miniaturization design, that is, ensure that the lens and the image sensor have sufficient adjustment space during the assembly process, thereby improving the assembly yield of the lens module. In addition, the optical system 10 when the above relationship is satisfied will also have a larger depth of focus, which is conducive to obtaining more depth information on the object side. When BFL / TTL<0.2, the processing tolerance allowed by the module during the assembly process is too small, resulting in too low a yield and increased difficulty in the production process. At the same time, it cannot ensure that the optical system 10 has sufficient depth of focus, resulting in poor imaging quality.

[0094] 0.8≤SDL1 / Imgh≤1.2; wherein Imgh is the image height corresponding to the maximum field angle of the optical system 10. Specifically, SDL1 / Imgh in some embodiments may be 0.92, 0.94, 0.98, 1, 1.02, 1.04 or 1.06. The size of the maximum effective aperture of the first lens L1 determines the amount of light passing through the entire optical system 10, while the size of the photosensitive surface determines the image clarity and pixel size of the entire camera system. The reasonable combination of the two can ensure appropriate imaging brightness and image clarity. When SDL1 / Imgh>1.2, it will cause overexposure and excessive brightness of the image, affecting the image quality; and when SDL1 / Imgh<0.8, it will cause insufficient light passing through and insufficient relative brightness of the light, which will cause a decrease in the sensitivity of the image.

[0095] 10mm 2 ≤(R9*R10) / (R9 / R10)≤25mm 2 ; R9 is the curvature radius of the object side surface S9 of the fifth lens L5 at the optical axis, and R10 is the curvature radius of the image side surface S10 of the fifth lens L5 at the optical axis. Specifically, in some embodiments, (R9*R10) / (R9 / R10) may be 14 mm 2 、14.2mm 2 、14.5mm 2 , 15mm 2 、16mm 2 、18mm 2 、19mm 2 , 20mm 2 , 21mm 2 , 21.2mm 2, 21.5mm 2 or 21.7mm 2 . When the above relationship is satisfied, the curvature radii of the object side S9 and the image side S10 of the fifth lens L5 can be reasonably configured, which can balance the optical path difference between the edge light and the paraxial light of the optical system 10, reasonably correct the field curvature and astigmatism, and reduce the system sensitivity and improve the assembly stability. When (R9*R10)+(R9 / R10)>25, the field curvature of the optical system 10 will be too large; when (R9*R10)+(R9 / R10)<10, the sensitivity of the system will increase, resulting in a decrease in production yield.

[0096] It should be noted that the ranges of the above relationship formulas and the corresponding effects are for the aforementioned seven-piece lens structure. When the optical system 10 satisfies the above relationship formulas and is provided with an optical path deflection element P1, the optical system 10 can not only effectively suppress stray light and aberrations and have good light transmittance, but also has a greater depth of focus than ordinary micro periscope lenses, thereby meeting the needs of high-definition imaging and long-range shooting.

[0097] Next, the optical system 10 of the present application is described with more specific and detailed embodiments:

[0098] First embodiment

[0099] refer to Figure 1 and Figure 2 In the first embodiment, the optical system 10 includes, from the object side to the image side, an optical path refractive element P1, a first lens L1 with positive refractive power, a second lens L2 with negative refractive power, a third lens L3 with negative refractive power, an aperture stop (not shown), a fourth lens L4 with positive refractive power, a fifth lens L5 with negative refractive power, a sixth lens L6 with negative refractive power, and a seventh lens L7 with positive refractive power. Figure 2 The diagram includes a longitudinal spherical aberration diagram, an astigmatism diagram and a distortion diagram of the optical system 10 in the first embodiment, wherein the reference wavelength of the astigmatism diagram and the distortion diagram is 587.56 nm.

[0100] The object-side surface S1 of the first lens L1 is convex at the paraxial position, and the image-side surface S2 is convex at the paraxial position; the object-side surface S1 is convex at the circumference, and the image-side surface S2 is concave at the circumference.

[0101] The object-side surface S3 of the second lens L2 is concave at the paraxial position, and the image-side surface S4 is concave at the paraxial position; the object-side surface S3 is convex at the circumference, and the image-side surface S4 is convex at the circumference.

[0102] The object-side surface S5 of the third lens L3 is convex at the paraxial position, and the image-side surface S6 is concave at the paraxial position; the object-side surface S5 is concave at the circumference, and the image-side surface S6 is concave at the circumference.

[0103] The object-side surface S7 of the fourth lens L4 is convex at the paraxial position, and the image-side surface S8 is concave at the paraxial position; the object-side surface S7 is convex at the circumference, and the image-side surface S8 is convex at the circumference.

[0104] The object-side surface S9 of the fifth lens L5 is convex at the paraxial position, and the image-side surface S10 is concave at the paraxial position; the object-side surface S9 is concave at the circumference, and the image-side surface S10 is concave at the circumference.

[0105] The object-side surface S11 of the sixth lens L6 is concave at the paraxial position, and the image-side surface S12 is concave at the paraxial position; the object-side surface S11 is concave at the circumference, and the image-side surface S12 is convex at the circumference.

[0106] The object-side surface S13 of the seventh lens L7 is convex at the paraxial position, and the image-side surface S14 is concave at the paraxial position; the object-side surface S13 is concave at the circumference, and the image-side surface S14 is convex at the circumference.

[0107] The object side surface and the image side surface of each lens from the first lens L1 to the seventh lens L7 are all aspherical surfaces. By matching the aspherical surface shape of each lens in the optical system 10, the problem of field distortion of the optical system 10 can be effectively solved, and the lens can achieve excellent optical effects in a smaller and thinner case, thereby making the optical system 10 have a smaller volume, which is conducive to the miniaturization design of the optical system 10.

[0108] In addition, the material of each lens in the optical system 10 is plastic. The use of plastic lenses can reduce the manufacturing cost of the optical system 10.

[0109] The lens parameters of the optical system 10 are given in the following Tables 1 and 2. Table 2 shows the aspheric coefficients of the corresponding surfaces of the lenses in Table 1, where k is the cone coefficient and Ai is the coefficient corresponding to the i-th high-order term in the aspheric surface formula. The elements from the object plane to the image plane (imaging plane S15, which can also be understood as the photosensitive surface of the photosensitive element during later assembly) are arranged in the order of the elements from top to bottom in Table 1. The surfaces corresponding to the surface numbers 1 and 2 respectively represent the object side surface S1 and the image side surface S2 of the first lens L1, 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 the image side surface of the corresponding surface number on the optical axis. The absolute value of the first value of the lens in the "thickness" parameter column is the thickness of the lens on the optical axis, and the absolute value of the second value is the distance from the image side surface of the lens to the object side surface of the next optical element on the optical axis. The optical axes of the lenses in the embodiments of the present application are on the same straight line, and the straight line serves as the optical axis of the optical system 10. It should be noted that in the following embodiments, the infrared cut-off filter 110 (the infrared filter in the table) may be used as a component in the optical system 10, or may not be used as a component in the optical system 10, but in either case, the distance from the image side surface S14 to the imaging surface S15 of the seventh lens L7 should be included in the value of the thickness parameter corresponding to the infrared cut-off filter 110 in the table.

[0110] In the first embodiment, the effective focal length f of the optical system 10 is 18.76 mm, the aperture number FNO is 2.86, the maximum field angle (ie, the viewing angle in the diagonal direction) FOV is 20.37°, and the total optical length TTL is 17.86 mm.

[0111] In addition, in the parameter tables of the following embodiments (the first embodiment to the sixth embodiment), the reference wavelength of the refractive index, Abbe number and focal length of each lens is 587.56 nm. In addition, the relationship calculation and lens structure of each embodiment shall be based on the lens parameters (such as Table 1, Table 2, Table 3, Table 4, etc.).

[0112] Table 1

[0113]

[0114]

[0115] Table 2

[0116] Surface number k A4 A6 A8 A10 A12 A14 1 -7.0632E-01 5.4000E-04 3.0000E-05 0.0000E+00 0.0000E+00 0.0000E+00 0.0000E+00 2 -1.0790E+00 1.4100E-03 0.0000E+00 0.0000E+00 0.0000E+00 0.0000E+00 0.0000E+00 3 6.3439E+01 -3.3100E-03 3.0000E-04 -2.0000E-05 0.0000E+00 0.0000E+00 0.0000E+00 4 1.3719E+01 -6.2000E-04 2.1000E-04 0.0000E+00 -3.0000E-05 1.0000E-05 0.0000E+00 5 7.2127E+01 -5.2000E-04 2.4000E-04 1.0000E-05 -5.0000E-05 2.0000E-05 -1.0000E-05 6 6.5900E-03 -7.7800E-03 3.0000E-04 -6.0000E-05 1.0000E-05 0.0000E+00 0.0000E+00 7 5.8450E-02 -5.6800E-03 6.2000E-04 -4.0000E-05 0.0000E+00 0.0000E+00 0.0000E+00 8 5.9639E+01 -6.1700E-03 9.8000E-04 -1.1000E-04 0.0000E+00 0.0000E+00 0.0000E+00 9 -4.8264E+00 -5.8200E-03 5.0000E-05 2.1000E-04 -3.0000E-05 0.0000E+00 0.0000E+00 10 3.4632E-01 -1.0470E-02 5.3000E-04 3.0000E-04 -4.0000E-05 0.0000E+00 0.0000E+00 11 5.1373E+01 7.1000E-04 2.4000E-04 4.0000E-05 1.0000E-05 0.0000E+00 0.0000E+00 12 5.5006E+01 9.0000E-05 -6.0000E-05 -2.0000E-05 -1.0000E-05 0.0000E+00 0.0000E+00 13 1.8997E-01 -6.7400E-03 5.6000E-04 -1.2000E-04 9.0000E-05 -4.0000E-05 1.0000E-05 14 -1.9885E+00 -2.1800E-03 2.5000E-04 3.0000E-05 0.0000E+00 1.0000E-05 0.0000E+00

[0117] In the first embodiment, the optical system 10 satisfies the following relationships:

[0118] SDL1*FNO=20.35mm; SDL1 is the maximum effective aperture of the object side S1 of the first lens L1, and FNO is the aperture number of the optical system 10. The above optical system 10 can reasonably control the ratio between the maximum effective aperture of the object side S1 of the first lens L1 and the aperture number of the system, so that the aperture of the aperture stop and the effective aperture of the first lens L1 are well matched, and the effective aperture of the first lens L1 is prevented from being too small and the aperture of the aperture stop is too large, so as to avoid excessive adjustment of the incident light between the two and generating too much stray light; at the same time, it can also prevent the effective aperture of the first lens L1 from being too large and the aperture of the aperture stop from being too small, so as to avoid the ineffective light of the outer field of view from passing through the aperture stop along with the light of the central field of view to be incident on the imaging surface S15 of the system, so as to effectively and reasonably intercept the edge light of the outer field of view, suppress the generation of aberrations such as spherical aberration and field curvature, and thus effectively improve the clarity of the imaging picture. By satisfying the above constraints on the effective aperture and the aperture number of the first lens L1, while suppressing stray light and system aberrations, it is also possible to avoid excessive interception of the central field of view light, which would lead to insufficient light throughput of the system, so that the system can achieve a good coordination between suppressing aberrations and maintaining good light throughput, so that the optical system 10 has good imaging brightness, thereby improving imaging clarity.

[0119] ETL5 / CTL5=1.39; ETL5 is the thickness of the fifth lens L5 at the maximum effective aperture, and CTL5 is the thickness of the fifth lens L5 at the optical axis. When the above relationship is satisfied, the central structure of the fifth lens L5 has a thinner design than the edge structure, which can effectively balance the optical path difference between the light of the central field of view and the edge field of view in the optical system 10, prevent the optical path difference from being too large, and enable the light of the central field of view and the edge field of view to converge near the imaging surface of the system, thereby realizing the function of correcting the field curvature. In addition, the fifth lens L5 that satisfies the above relationship can also prevent the center from being too thin or too thick compared to the edge, thereby meeting the precision requirements of production and processing and ensuring the molding yield.

[0120] FOV / AngleS1=0.44; FOV is the maximum field of view of the optical system 10, and AngleS1 is the maximum angle between the tangent plane of the object side surface S1 of the first lens L1 and the plane perpendicular to the optical axis. The maximum tilt angle of the object side surface S1 of the first lens L1 and the field of view of the system play a decisive role in the entire optical system 10 receiving the object space light information. By satisfying the constraints of the above relationship conditions, the two can allow a wide range of light information to enter the optical system 10, thereby satisfying the large field of view shooting effect.

[0121] FNO / TTL=0.16mm -1; TTL is the distance on the optical axis from the object side S1 of the first lens L1 to the imaging surface of the optical system 10. Compared with ordinary cameras, periscope cameras have a problem of low light transmission. When the above relationship is met, the optical system 10 can take into account both the telephoto performance and the miniaturized design requirements of the optical system 10, and provide sufficient light transmission for video shooting, meeting the needs of high-quality and high-definition shooting.

[0122] SDL1 / RAD(FOV)=19.99mm / rad; RAD(FOV) is the radian value of the maximum field of view of the optical system 10. In the optical system 10, the maximum effective aperture of the first lens L1 determines the field of view of the system, and the reasonable combination of the two can ensure that a wide range of light information enters the optical system 10 for imaging. If the above relationship is satisfied, the field of view of the optical system 10 will not be too small, and the effective aperture of the first lens L1 can form a good fit with the field of view of the system, thereby suppressing the generation of distortion and preventing the imaging of the external field of view from being distorted.

[0123] TTL / f=0.95; TTL is the distance from the object side surface S1 of the first lens L1 to the imaging surface of the optical system 10 on the optical axis, and f is the effective focal length of the optical system 10. When the above relationship is satisfied, the focal length and the total optical length of the optical system 10 can be reasonably controlled, which can not only realize the miniaturization design of the optical system 10, but also promote the better convergence of light on the imaging surface.

[0124] Imgh / TTL=0.38; Imgh is the image height corresponding to the maximum field angle of the optical system 10, and TTL is the distance on the optical axis from the object side surface S1 of the first lens L1 to the imaging surface S15 of the optical system 10. When the above relationship is satisfied, the optical system 10 can take into account both miniaturization and high-definition photography.

[0125] BFL / TTL=0.437; BFL is the minimum value of the image side surface S14 of the seventh lens L7 to the imaging surface of the optical system 10 in the direction of the optical axis, and TTL is the distance from the object side surface S1 of the first lens L1 to the imaging surface of the optical system 10 on the optical axis. When the above relationship is satisfied, the optical system 10 can ensure sufficient focusing range while meeting the requirements of miniaturization design, that is, ensuring that the lens and the image sensor have sufficient adjustment space during the assembly process, thereby improving the assembly yield of the lens module. In addition, when the above relationship is satisfied, the optical system 10 will also have a larger depth of focus, which is conducive to obtaining more depth information on the object side.

[0126] SDL1 / Imgh=1.04; Imgh is the image height corresponding to the maximum field angle of the optical system 10. The maximum effective aperture of the first lens L1 determines the amount of light passing through the entire optical system 10, while the size of the photosensitive surface determines the image clarity and pixel size of the entire camera system. The reasonable combination of the two can ensure appropriate imaging brightness and imaging clarity.

[0127] (R9*R10) / (R9 / R10)≤21.74mm 2 ; R9 is the curvature radius of the object side surface S9 of the fifth lens L5 at the optical axis, and R10 is the curvature radius of the image side surface S10 of the fifth lens L5 at the optical axis. When the above relationship is satisfied, the curvature radii of the object side surface S9 and the image side surface S10 of the fifth lens L5 can be reasonably configured, which can balance the optical path difference between the edge light and the paraxial light of the optical system 10, reasonably correct the field curvature and astigmatism, and at the same time reduce the system sensitivity and improve the assembly stability.

[0128] in addition, Figure 2 The optical system 10 includes a longitudinal spherical aberration diagram (Longitudinal Spherical Aberration), which indicates the deviation of the convergence focus of light of different wavelengths after passing through the lens. The ordinate of the longitudinal spherical aberration diagram indicates the normalized pupil coordinate (Normalized Pupil Coordinator) from the center of the pupil to the edge of the pupil, and the abscissa indicates the distance from the imaging plane to the intersection of the light and the optical axis (in mm). It can be seen from the longitudinal spherical aberration diagram that the degree of deviation of the convergence focus of light of each wavelength in the first embodiment tends to be consistent, and the diffuse spots or color halos in the imaging picture are effectively suppressed. Figure 2 Also included is a field curvature diagram (ASTIGMATIC FIELD CURVES) of the optical system 10, where the S curve represents the sagittal field curvature at 587.56 nm, and the T curve represents the meridian field curvature at 587.56 nm. As can be seen from the figure, the field curvature of the system is small, the field curvature and astigmatism of each field of view (especially the edge field of view) are well corrected, and the center and edge of the field of view have clear imaging. Figure 2 It also includes a distortion diagram (DISTORTION) of the optical system 10. It can be seen from the diagram that the image deformation caused by the main light beam is small and the imaging quality of the system is excellent.

[0129] Second embodiment

[0130] refer to Figure 3 and Figure 4In the second embodiment, the optical system 10 includes, from the object side to the image side, an optical path refractive element P1, a first lens L1 with positive refractive power, a second lens L2 with positive refractive power, a third lens L3 with negative refractive power, an aperture stop (not shown), a fourth lens L4 with positive refractive power, a fifth lens L5 with negative refractive power, a sixth lens L6 with negative refractive power, and a seventh lens L7 with positive refractive power. Figure 4 The diagram includes a longitudinal spherical aberration diagram, an astigmatism diagram and a distortion diagram of the optical system 10 in the second embodiment, wherein the reference wavelength of the astigmatism diagram and the distortion diagram is 587.56 nm.

[0131] The object-side surface S1 of the first lens L1 is convex at the paraxial position, and the image-side surface S2 is convex at the paraxial position; the object-side surface S1 is convex at the circumference, and the image-side surface S2 is concave at the circumference.

[0132] The object-side surface S3 of the second lens L2 is concave at the paraxial position, and the image-side surface S4 is convex at the paraxial position; the object-side surface S3 is convex at the circumference, and the image-side surface S4 is convex at the circumference.

[0133] The object-side surface S5 of the third lens L3 is concave at the paraxial position, and the image-side surface S6 is concave at the paraxial position; the object-side surface S5 is concave at the circumference, and the image-side surface S6 is concave at the circumference.

[0134] The object-side surface S7 of the fourth lens L4 is convex at the paraxial position, and the image-side surface S8 is concave at the paraxial position; the object-side surface S7 is convex at the circumference, and the image-side surface S8 is concave at the circumference.

[0135] The object-side surface S9 of the fifth lens L5 is convex at the paraxial position, and the image-side surface S10 is concave at the paraxial position; the object-side surface S9 is convex at the circumference, and the image-side surface S10 is concave at the circumference.

[0136] The object-side surface S11 of the sixth lens L6 is concave at the paraxial position, and the image-side surface S12 is concave at the paraxial position; the object-side surface S11 is concave at the circumference, and the image-side surface S12 is convex at the circumference.

[0137] The object-side surface S13 of the seventh lens L7 is convex at the paraxial position, and the image-side surface S14 is concave at the paraxial position; the object-side surface S13 is convex at the circumference, and the image-side surface S14 is concave at the circumference.

[0138] In addition, the lens parameters of the optical system 10 in the second embodiment are given in Table 3 and Table 4, wherein the definitions of the structures and parameters can be obtained from the first embodiment and are not described in detail here.

[0139] Table 3

[0140]

[0141] Table 4

[0142]

[0143]

[0144] The camera module 10 in this embodiment satisfies the following relationship:

[0145] SDL1*FNO 20.74 Imgh / TTL 0.37 ETL5 / CTL5 1.44 BFL / TTL 0.439 FOV / AngleS1 0.42 SDL1 / Imgh 1.06 FNO / TTL 0.16 (R9*R10) / (R9 / R10) 19.24 SDL1 / RAD(FOV) 20.55 TTL / f 0.96

[0146] Depend on Figure 4 As can be seen from the aberration diagram in , the longitudinal spherical aberration, field curvature and distortion of the optical system 10 are all well controlled, so that the optical system 10 of this embodiment has good imaging quality.

[0147] Third embodiment

[0148] refer to Figure 5 and Figure 6 In the third embodiment, the optical system 10 includes, from the object side to the image side, an optical path refractive element P1, a first lens L1 with positive refractive power, a second lens L2 with negative refractive power, a third lens L3 with negative refractive power, an aperture stop (not shown), a fourth lens L4 with negative refractive power, a fifth lens L5 with negative refractive power, a sixth lens L6 with negative refractive power, and a seventh lens L7 with positive refractive power. Figure 6 The diagram includes a longitudinal spherical aberration diagram, an astigmatism diagram and a distortion diagram of the optical system 10 in the third embodiment, wherein the reference wavelength of the astigmatism diagram and the distortion diagram is 587.56 nm.

[0149] The object-side surface S1 of the first lens L1 is convex at the paraxial position, and the image-side surface S2 is convex at the paraxial position; the object-side surface S1 is convex at the circumference, and the image-side surface S2 is concave at the circumference.

[0150] The object-side surface S3 of the second lens L2 is convex at the paraxial position, and the image-side surface S4 is concave at the paraxial position; the object-side surface S3 is concave at the circumference, and the image-side surface S4 is concave at the circumference.

[0151] The object-side surface S5 of the third lens L3 is convex at the paraxial position, and the image-side surface S6 is concave at the paraxial position; the object-side surface S5 is convex at the circumference, and the image-side surface S6 is convex at the circumference.

[0152] The object-side surface S7 of the fourth lens L4 is concave at the paraxial position, and the image-side surface S8 is concave at the paraxial position; the object-side surface S7 is concave at the circumference, and the image-side surface S8 is convex at the circumference.

[0153] The object-side surface S9 of the fifth lens L5 is convex at the paraxial position, and the image-side surface S10 is concave at the paraxial position; the object-side surface S9 is convex at the circumference, and the image-side surface S10 is concave at the circumference.

[0154] The object-side surface S11 of the sixth lens L6 is concave at the paraxial position, and the image-side surface S12 is concave at the paraxial position; the object-side surface S11 is concave at the circumference, and the image-side surface S12 is convex at the circumference.

[0155] The object-side surface S13 of the seventh lens L7 is convex at the paraxial position, and the image-side surface S14 is concave at the paraxial position; the object-side surface S13 is concave at the circumference, and the image-side surface S14 is convex at the circumference.

[0156] In addition, the lens parameters of the optical system 10 in the third embodiment are given in Table 5 and Table 6, wherein the definitions of the structures and parameters can be obtained from the first embodiment and are not elaborated here.

[0157] Table 5

[0158]

[0159]

[0160] Table 6

[0161] Surface number K A4 A6 A8 A10 A12 A14 1 -7.190E-01 5.400E-04 2.000E-05 0.000E+00 0.000E+00 0.000E+00 0.000E+00 2 -1.917E+00 1.460E-03 0.000E+00 0.000E+00 0.000E+00 0.000E+00 0.000E+00 3 -7.813E+01 -3.310E-03 2.900E-04 -2.000E-05 0.000E+00 0.000E+00 0.000E+00 4 1.518E+01 -2.780E-03 9.600E-04 2.400E-04 -2.800E-04 1.000E-04 -2.000E-05 5 6.844E+01 -1.610E-03 7.600E-04 3.100E-04 -3.600E-04 1.300E-04 -3.000E-05 6 1.103E+00 -7.630E-03 3.200E-04 -6.000E-05 1.000E-05 0.000E+00 0.000E+00 7 1.802E+00 -5.430E-03 6.500E-04 -4.000E-05 0.000E+00 0.000E+00 0.000E+00 8 7.186E+00 -6.650E-03 9.100E-04 -1.100E-04 0.000E+00 0.000E+00 0.000E+00 9 -4.580E+00 -5.680E-03 1.200E-04 2.200E-04 -4.000E-05 0.000E+00 0.000E+00 10 2.830E-03 -1.111E-02 3.200E-04 2.900E-04 -4.000E-05 0.000E+00 0.000E+00 11 4.647E+01 -2.100E-04 2.800E-04 5.000E-05 1.000E-05 0.000E+00 0.000E+00 12 4.559E+01 1.160E-03 0.000E+00 -1.000E-05 -1.000E-05 0.000E+00 0.000E+00 13 1.682E-01 -4.010E-03 2.000E-04 -1.800E-04 1.300E-04 -5.000E-05 1.000E-05 14 1.448E+00 5.000E-04 -2.40E-04 2.000E-04 -5.000E-05 1.000E-05 0.000E+00

[0162] The camera module 10 in this embodiment satisfies the following relationship:

[0163]

[0164]

[0165] Depend on Figure 6 As can be seen from the aberration diagram in , the longitudinal spherical aberration, field curvature and distortion of the optical system 10 are all well controlled, so that the optical system 10 of this embodiment has good imaging quality.

[0166] Fourth embodiment

[0167] refer to Figure 7 and Figure 8 In the fourth embodiment, the optical system 10 includes, from the object side to the image side, an optical path refractive element P1, a first lens L1 with positive refractive power, a second lens L2 with negative refractive power, a third lens L3 with negative refractive power, an aperture stop (not shown), a fourth lens L4 with negative refractive power, a fifth lens L5 with positive refractive power, a sixth lens L6 with negative refractive power, and a seventh lens L7 with positive refractive power. Figure 8 The diagram includes a longitudinal spherical aberration diagram, an astigmatism diagram and a distortion diagram of the optical system 10 in the fourth embodiment, wherein the reference wavelength of the astigmatism diagram and the distortion diagram is 587.56 nm.

[0168] The object-side surface S1 of the first lens L1 is convex at the paraxial position, and the image-side surface S2 is convex at the paraxial position; the object-side surface S1 is convex at the circumference, and the image-side surface S2 is concave at the circumference.

[0169] The object-side surface S3 of the second lens L2 is concave at the paraxial position, and the image-side surface S4 is concave at the paraxial position; the object-side surface S3 is concave at the circumference, and the image-side surface S4 is concave at the circumference.

[0170] The object-side surface S5 of the third lens L3 is convex at the paraxial position, and the image-side surface S6 is concave at the paraxial position; the object-side surface S5 is concave at the circumference, and the image-side surface S6 is concave at the circumference.

[0171] The object-side surface S7 of the fourth lens L4 is convex at the paraxial position, and the image-side surface S8 is concave at the paraxial position; the object-side surface S7 is convex at the circumference, and the image-side surface S8 is concave at the circumference.

[0172] The object-side surface S9 of the fifth lens L5 is convex at the paraxial position, and the image-side surface S10 is concave at the paraxial position; the object-side surface S9 is convex at the circumference, and the image-side surface S10 is concave at the circumference.

[0173] The object-side surface S11 of the sixth lens L6 is concave at the paraxial position, and the image-side surface S12 is concave at the paraxial position; the object-side surface S11 is concave at the circumference, and the image-side surface S12 is convex at the circumference.

[0174] The object-side surface S13 of the seventh lens L7 is convex at the paraxial position, and the image-side surface S14 is concave at the paraxial position; the object-side surface S13 is concave at the circumference, and the image-side surface S14 is convex at the circumference.

[0175] In addition, the lens parameters of the optical system 10 in the fourth embodiment are given in Table 7 and Table 8, wherein the definitions of the structures and parameters can be obtained from the first embodiment and will not be repeated here.

[0176] Table 7

[0177]

[0178]

[0179] Table 8

[0180] Surface number K A4 A6 A8 A10 A12 A14 1 -8.300E-01 4.400E-04 2.000E-05 0.000E+00 0.000E+00 0.000E+00 0.000E+00 2 4.582E-01 1.320E-03 -1.000E-05 0.000E+00 0.000E+00 0.000E+00 0.000E+00 3 9.900E+01 -3.290E-03 3.000E-04 -2.000E-05 0.000E+00 0.000E+00 0.000E+00 4 -6.244E+00 3.400E-03 -4.340E-03 9.500E-04 2.100E-04 -1.500E-04 3.000E-05 5 6.970E+01 7.290E-03 -5.200E-03 1.090E-03 1.500E-04 -1.200E-04 3.000E-05 6 1.047E+00 -7.760E-03 3.100E-04 -6.000E-05 1.000E-05 0.000E+00 0.000E+00 7 9.895E+01 -5.170E-03 6.600E-04 -3.000E-05 0.000E+00 0.000E+00 0.000E+00 8 1.296E+01 -6.610E-03 9.700E-04 -8.000E-05 1.000E-05 0.000E+00 0.000E+00 9 -4.536E+00 -5.490E-03 1.000E-04 1.700E-04 -4.000E-05 0.000E+00 0.000E+00 10 3.301E-02 -1.105E-02 2.800E-04 4.100E-04 -2.000E-05 1.000E-05 0.000E+00 11 3.538E+01 2.880E-03 6.100E-04 1.500E-04 5.000E-05 0.000E+00 0.000E+00 12 2.542E+01 -1.200E-04 4.100E-04 -9.000E-05 -2.000E-05 0.000E+00 0.000E+00 13 3.957E-01 -3.160E-03 2.800E-04 -8.000E-05 7.000E-05 -3.000E-05 1.000E-05 14 3.020E+00 1.400E-04 2.800E-04 -1.600E-04 1.600E-04 -7.000E-05 2.000E-05

[0181] The camera module 10 in this embodiment satisfies the following relationship:

[0182] SDL1*FNO 18.63 Imgh / TTL 0.40 ETL5 / CTL5 0.96 BFL / TTL 0.333 FOV / AngleS1 0.57 SDL1 / Imgh 0.95 FNO / TTL 0.17 (R9*R10) / (R9 / R10) 20.04 SDL1 / RAD(FOV) 16.24 TTL / f 1.01

[0183] Depend on Figure 8As can be seen from the aberration diagram in , the longitudinal spherical aberration, field curvature and distortion of the optical system 10 are all well controlled, so that the optical system 10 of this embodiment has good imaging quality.

[0184] Fifth embodiment

[0185] refer to Fig. 9 and Fig.10 In the fifth embodiment, the optical system 10 includes, from the object side to the image side, an optical path refractive element P1, a first lens L1 with positive refractive power, a second lens L2 with negative refractive power, a third lens L3 with positive refractive power, an aperture stop (not shown), a fourth lens L4 with negative refractive power, a fifth lens L5 with negative refractive power, a sixth lens L6 with negative refractive power, and a seventh lens L7 with positive refractive power. Fig.10 The diagram includes a longitudinal spherical aberration diagram, an astigmatism diagram and a distortion diagram of the optical system 10 in the fifth embodiment, wherein the reference wavelength of the astigmatism diagram and the distortion diagram is 587.56 nm.

[0186] The object-side surface S1 of the first lens L1 is convex at the paraxial position, and the image-side surface S2 is convex at the paraxial position; the object-side surface S1 is convex at the circumference, and the image-side surface S2 is concave at the circumference.

[0187] The object-side surface S3 of the second lens L2 is convex at the paraxial position, and the image-side surface S4 is concave at the paraxial position; the object-side surface S3 is concave at the circumference, and the image-side surface S4 is concave at the circumference.

[0188] The object-side surface S5 of the third lens L3 is convex at the paraxial position, and the image-side surface S6 is concave at the paraxial position; the object-side surface S5 is convex at the circumference, and the image-side surface S6 is concave at the circumference.

[0189] The object-side surface S7 of the fourth lens L4 is concave at the paraxial position, and the image-side surface S8 is convex at the paraxial position; the object-side surface S7 is convex at the circumference, and the image-side surface S8 is concave at the circumference.

[0190] The object-side surface S9 of the fifth lens L5 is convex at the paraxial position, and the image-side surface S10 is concave at the paraxial position; the object-side surface S9 is convex at the circumference, and the image-side surface S10 is concave at the circumference.

[0191] The object-side surface S11 of the sixth lens L6 is concave at the paraxial position, and the image-side surface S12 is concave at the paraxial position; the object-side surface S11 is concave at the circumference, and the image-side surface S12 is convex at the circumference.

[0192] The object-side surface S13 of the seventh lens L7 is convex at the paraxial position, and the image-side surface S14 is concave at the paraxial position; the object-side surface S13 is convex at the circumference, and the image-side surface S14 is concave at the circumference.

[0193] In addition, the lens parameters of the optical system 10 in the fifth embodiment are given in Tables 9 and 10, wherein the definitions of the structures and parameters can be obtained from the first embodiment and will not be elaborated here.

[0194] Table 9

[0195]

[0196] Table 10

[0197]

[0198]

[0199] The camera module 10 in this embodiment satisfies the following relationship:

[0200] SDL1*FNO 17.84 Imgh / TTL 0.40 ETL5 / CTL5 1.27 BFL / TTL 0.363 FOV / AngleS1 0.55 SDL1 / Imgh 0.92 FNO / TTL 0.17 (R9*R10) / (R9 / R10) 20.66 SDL1 / RAD(FOV) 15.81 TTL / f 1.01

[0201] Depend on Fig.10 As can be seen from the aberration diagram in , the longitudinal spherical aberration, field curvature and distortion of the optical system 10 are all well controlled, so that the optical system 10 of this embodiment has good imaging quality.

[0202] Sixth embodiment

[0203] refer to Fig.11 and Fig.12 In the sixth embodiment, the optical system 10 includes, from the object side to the image side, an optical path refractive element P1, a first lens L1 with positive refractive power, a second lens L2 with negative refractive power, a third lens L3 with negative refractive power, an aperture stop (not shown), a fourth lens L4 with positive refractive power, a fifth lens L5 with negative refractive power, a sixth lens L6 with positive refractive power, and a seventh lens L7 with negative refractive power. Fig.12 The sixth embodiment includes a longitudinal spherical aberration diagram, an astigmatism diagram and a distortion diagram of the optical system 10, wherein the reference wavelength of the astigmatism diagram and the distortion diagram is 587.56 nm.

[0204] The object-side surface S1 of the first lens L1 is convex at the paraxial position, and the image-side surface S2 is convex at the paraxial position; the object-side surface S1 is convex at the circumference, and the image-side surface S2 is concave at the circumference.

[0205] The object-side surface S3 of the second lens L2 is concave at the paraxial position, and the image-side surface S4 is concave at the paraxial position; the object-side surface S3 is convex at the circumference, and the image-side surface S4 is convex at the circumference.

[0206] The object-side surface S5 of the third lens L3 is convex at the paraxial position, and the image-side surface S6 is concave at the paraxial position; the object-side surface S5 is concave at the circumference, and the image-side surface S6 is concave at the circumference.

[0207] The object-side surface S7 of the fourth lens L4 is convex at the paraxial position, and the image-side surface S8 is concave at the paraxial position; the object-side surface S7 is convex at the circumference, and the image-side surface S8 is concave at the circumference.

[0208] The object-side surface S9 of the fifth lens L5 is convex at the paraxial position, and the image-side surface S10 is concave at the paraxial position; the object-side surface S9 is concave at the circumference, and the image-side surface S10 is concave at the circumference.

[0209] The object-side surface S11 of the sixth lens L6 is concave at the paraxial position, and the image-side surface S12 is convex at the paraxial position; the object-side surface S11 is convex at the circumference, and the image-side surface S12 is convex at the circumference.

[0210] The object-side surface S13 of the seventh lens L7 is convex at the paraxial position, and the image-side surface S14 is concave at the paraxial position; the object-side surface S13 is convex at the circumference, and the image-side surface S14 is concave at the circumference.

[0211] In addition, the lens parameters of the optical system 10 in the sixth embodiment are given in Table 11 and Table 12, wherein the definitions of the structures and parameters can be obtained from the first embodiment and will not be repeated here.

[0212] Table 11

[0213]

[0214]

[0215] Table 12

[0216] Surface number K A4 A6 A8 A10 A12 A14 1 -7.332E-01 4.800E-04 4.000E-05 0.000E+00 0.000E+00 0.000E+00 0.000E+00 2 -1.107E+00 1.410E-03 0.000E+00 0.000E+00 0.000E+00 0.000E+00 0.000E+00 3 7.336E+01 -3.350E-03 3.000E-04 -2.000E-05 0.000E+00 0.000E+00 0.000E+00 4 1.566E+01 -4.900E-04 2.100E-04 -2.000E-05 -2.000E-05 1.000E-05 0.000E+00 5 7.317E+01 -4.800E-04 2.600E-04 -5.000E-05 -1.000E-05 1.000E-05 0.000E+00 6 2.509E-02 -7.780E-03 3.200E-04 -6.000E-05 1.000E-05 0.000E+00 0.000E+00 7 4.071E-01 -5.450E-03 6.500E-04 -4.000E-05 0.000E+00 0.000E+00 0.000E+00 8 4.619E+01 -6.120E-03 9.600E-04 -1.100E-04 0.000E+00 0.000E+00 0.000E+00 9 -4.464E+00 -5.580E-03 1.500E-04 2.200E-04 -3.000E-05 0.000E+00 0.000E+00 10 3.893E-01 -1.028E-02 4.500E-04 3.300E-04 -4.000E-05 0.000E+00 0.000E+00 11 4.171E+01 9.800E-04 2.600E-04 1.000E-05 1.000E-05 0.000E+00 0.000E+00 12 -4.629E+01 9.800E-04 1.500E-04 0.000E+00 -1.000E-05 0.000E+00 0.000E+00 13 7.469E-01 -5.410E-03 1.500E-04 6.000E-05 0.000E+00 0.000E+00 0.000E+00 14 -5.514E+00 -2.840E-03 8.000E-05 5.000E-05 0.000E+00 0.000E+00 0.000E+00

[0217] The camera module 10 in this embodiment satisfies the following relationship:

[0218] SDL1*FNO 20.55 Imgh / TTL 0.37 ETL5 / CTL5 1.70 BFL / TTL 0.427 FOV / AngleS1 0.43 SDL1 / Imgh 1.03 FNO / TTL 0.16 (R9*R10) / (R9 / R10) 13.81 SDL1 / RAD(FOV) 20.15 TTL / f 0.96

[0219] Depend on Fig.12 As can be seen from the aberration diagram in , the longitudinal spherical aberration, field curvature and distortion of the optical system 10 are all well controlled, so that the optical system 10 of this embodiment has good imaging quality.

[0220] refer to Fig.13Some embodiments of the present application also provide a camera module 20, the camera module 20 includes the optical system 10 and the image sensor 210 of any one of the above embodiments, and the image sensor 210 is arranged on the image side of the optical system 10. The image sensor 210 can be a CCD (Charge Coupled Device) or a CMOS (Complementary Metal Oxide Semiconductor). Generally, during assembly, the imaging surface S17 of the optical system 10 overlaps with the photosensitive surface of the image sensor 210. Furthermore, when an optical path deflection element P1 is provided in the optical system 10, the camera module 20 can be applied to electronic devices as a periscope camera module.

[0221] In some embodiments, the camera module 20 includes an infrared cutoff filter 110 disposed between the seventh lens L7 and the image sensor 210, and the infrared cutoff filter 110 is used to filter out infrared light. In some embodiments, the infrared cutoff filter 110 can be mounted to the image end of the lens. In some embodiments, the camera module 20 also includes a protective glass, which is disposed between the infrared cutoff filter and the image sensor 210, and the protective glass is used to protect the image sensor 210.

[0222] By adopting the above-mentioned optical system 10, the camera module 20 can suppress stray light and system aberrations when shooting, and at the same time avoid excessive interception of central field light that causes insufficient system light throughput, thereby enabling the system to achieve good coordination between suppressing aberrations and maintaining good light throughput, so that good image brightness can be achieved during shooting, thereby improving image clarity.

[0223] refer to Fig.14 , some embodiments of the present application also provide an electronic device 30, and the camera module 20 is applied to the electronic device 30 so that the electronic device 30 has a camera function. Specifically, the electronic device 30 includes a fixing part 310, and the camera module 20 is installed on the fixing part 310, and the fixing part 310 can be a circuit board, a middle frame, a back cover and other components. The electronic device 30 can be, but is not limited to, a smart phone, a smart watch, an e-book reader, a vehicle-mounted camera device, a monitoring device, a drone, a medical device (such as an endoscope), a tablet computer, a biometric device (such as a fingerprint recognition device or a pupil recognition device, etc.), a PDA (Personal Digital Assistant), a drone, etc. By adopting the above-mentioned camera module 20, the imaging picture of the electronic device during shooting can not only effectively suppress stray light and aberrations, but also maintain good imaging brightness, so that the electronic device has excellent shooting performance.

[0224] The technical features of the above-described embodiments may be arbitrarily combined. To make the description concise, not all possible combinations of the technical features in the above-described 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.

[0225] The above-mentioned embodiments only express several implementation methods of the present invention, and the descriptions thereof are relatively specific and detailed, but they cannot be understood as limiting the scope of the invention patent. It should be pointed out that, for ordinary technicians in this field, several variations and improvements can be made without departing from the concept of the present invention, and these all belong to the protection scope of the present invention. Therefore, the protection scope of the patent of the present invention shall be subject to the attached claims.

Claims

1. An optical system, characterized in that: There are seven lenses with refractive power, including the following from the object side to the image side: A first lens having positive refractive power, wherein the object side surface of the first lens is convex at the paraxial position, and the image side surface of the first lens is convex at the paraxial position; a second lens having refractive power; a third lens having refractive power; Aperture; a fourth lens having a refractive power; a fifth lens having a refractive power, wherein the object side surface of the fifth lens is a convex surface at the paraxial position, and the image side surface of the fifth lens is a concave surface at the paraxial position; a sixth lens having a refractive power, wherein the object side surface of the sixth lens is a concave surface at the paraxial position, and the image side surface of the sixth lens is an aspherical surface at the paraxial position; a seventh lens having refractive power; The optical system satisfies the relationship: 16mm≤SDL1*FNO≤25mm, 12≤FOV / AngleS1≤25; Among them, SDL1 is the maximum effective aperture of the object side of the first lens, FNO is the aperture number of the optical system, FOV is the maximum field of view of the optical system, and AngleS1 is the maximum angle between the tangent plane of the object side of the first lens and the plane perpendicular to the optical axis.

2. The optical system according to claim 1, characterized in that The optical system satisfies the relationship: 1≤ETL5 / CTL5≤3; Wherein, ETL5 is the distance from the maximum effective aperture on the object side of the fifth lens to the maximum effective aperture on the image side in the direction of the optical axis, and CTL5 is the thickness of the fifth lens at the optical axis.

3. The optical system according to claim 1, characterized in that The image side surface of the third lens is concave at the paraxial position, the object side surface of the seventh lens is convex at the paraxial position, and the image side surface of the seventh lens is concave at the paraxial position.

4. The optical system according to claim 1, characterized in that The optical system satisfies the relationship: FNO / TTL≤0.2mm -1 ; Wherein, TTL is the distance from the object side surface of the first lens to the imaging surface of the optical system on the optical axis.

5. The optical system according to claim 1, characterized in that The optical system satisfies the relationship: 12mm / rad≤SDL1 / RAD(FOV)≤25mm / rad; Wherein, RAD(FOV) is the radian value of the maximum field of view angle of the optical system.

6. The optical system according to claim 1, characterized in that The optical system satisfies the relationship: 0.5≤TTL / f≤1.5; Wherein, TTL is the distance from the object side surface of the first lens to the imaging surface of the optical system on the optical axis, and f is the effective focal length of the optical system.

7. The optical system according to claim 1, characterized in that The optical system satisfies the relationship: 0.3≤Imgh / TTL≤0.5; Wherein, Imgh is the image height corresponding to the maximum field angle of the optical system, and TTL is the distance from the object side of the first lens to the imaging plane of the optical system on the optical axis.

8. The optical system according to claim 1, characterized in that The optical system satisfies the relationship: BFL / TTL>0.2; Wherein, BFL is the minimum value from the image side surface of the seventh lens to the imaging surface of the optical system in the direction of the optical axis, and TTL is the distance from the object side surface of the first lens to the imaging surface of the optical system on the optical axis.

9. The optical system according to claim 1, characterized in that The optical system satisfies the relationship: 0.8≤SDL1 / Imgh≤1.2; Wherein, Imgh is the image height corresponding to the maximum field angle of the optical system.

10. The optical system according to claim 1, characterized in that The optical system satisfies the relationship: 10mm 2 ≤(R9*R10) / (R9 / R10)≤25mm 2 ; Wherein, R9 is the curvature radius of the object side surface of the fifth lens at the optical axis, and R10 is the curvature radius of the image side surface of the fifth lens at the optical axis.

11. The optical system according to claim 1, characterized in that It includes an optical path deflecting element arranged on the object side of the first lens, and the optical path deflecting element is used to reflect the incident light to the first lens.

12. A camera module, characterized in that: The optical system comprises an image sensor and any one of claims 1 to 11, wherein the image sensor is arranged on the image side of the optical system.

13. An electronic device, characterized in that: Including the camera module described in claim 12.

Images