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, a first lens with positive refractive power, whose object side surface is convex at the near optical axis, and whose image side surface is concave at the near optical axis; a second lens with negative refractive power, whose object side surface is convex at the near optical axis, and whose image side surface is concave at the near optical axis; a third lens with positive refractive power, whose object side surface is convex at the near optical axis; a fourth lens; a fifth lens, whose image side surface is convex at the near optical axis; a sixth lens, whose image side surface is concave at the near optical axis; a seventh lens, whose object side surface is convex at the near optical axis, and whose image side surface is concave at the near optical axis, and both are aspherical surfaces, and at least one of them has an inflection point; the optical system also satisfies: 1.004<f / TTL<1.1; f is the effective focal length of the optical system, and TTL is the total optical length of the optical system. The above optical system has miniaturization and telephoto characteristics.

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] In recent years, the replacement cycle of mobile phones has become shorter and shorter, and the shooting functions have become more powerful. The market has become more and more stringent in terms of single-type lenses. As consumers have more diverse requirements for shooting environments, the types of lenses that adapt to different shooting environments are also increasing. Among them, telephoto lenses have a longer focal length, which can achieve a shallower depth of field, so they can better process the details of distant scenes and achieve the imaging effect of compressing the shooting distance.

[0003] However, traditional telephoto lenses often have the problem of being too large and having insufficient ability to process distant details. Summary of the invention

[0004] Based on this, it is necessary to provide an optical system, a camera module and an electronic device to solve the problem of how to compress the length of a telephoto lens and better handle distant details.

[0005] An optical system, comprising, in order from the object side to the image side along the optical axis:

[0006] A first lens having positive refractive power, wherein the object side surface of the first lens is convex at the near optical axis, and the image side surface of the first lens is concave at the near optical axis;

[0007] A second lens element having negative refractive power, wherein the object side surface of the second lens element is convex at the near optical axis, and the image side surface of the second lens element is concave at the near optical axis;

[0008] A third lens element having positive refractive power, wherein the object side surface of the third lens element is convex near the optical axis;

[0009] a fourth lens having a refractive power;

[0010] A fifth lens element having a refractive power, wherein the image side surface of the fifth lens element is a convex surface near the optical axis;

[0011] a sixth lens element having a refractive power, wherein the image side surface of the sixth lens element is a concave surface near the optical axis;

[0012] a seventh lens having refractive power, wherein the object side surface of the seventh lens is convex at the near optical axis, the image side surface is concave at the near optical axis, the object side surface and the image side surface are both aspherical surfaces, and at least one of the object side surface and the image side surface has an inflection point;

[0013] The optical system also satisfies the relationship:

[0014] 1.004<f / TTL<1.1; and

[0015] f is the effective focal length 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.

[0016] In the above optical system, the refractive power and surface configuration of the first lens are conducive to increasing the light input of the optical system and improving the image clarity. On the other hand, it is also conducive to increasing the field of view of the optical system and widening the shooting range. The front and rear lenses of the second lens both have positive refractive power. By making the second lens have the above refractive power and surface setting, it will be conducive to shortening the total length of the system and promoting the system to achieve aberration balance. The surface design of the third lens is conducive to strengthening the strength of the positive refractive power, thereby facilitating the correction of the aberrations generated by the object lens. The design of the fifth lens can also correct the aberrations such as astigmatism and distortion generated by the object lens. The design of the sixth lens is conducive to shortening the total length of the system. The seventh lens has the above surface design, which is conducive to the optical system to obtain a larger image surface to match the image sensor with higher pixels, and on the other hand, it can also increase the back focus of the optical system, so that the optical system has a sufficient safety distance during the module assembly process to avoid collision. On the other hand, through the above lens number, refractive power configuration and surface design, the optical system can be conducive to having a telephoto characteristic on the one hand, and on the other hand, it can also make the aberrations generated between the lenses better balanced, thereby suppressing the overall aberration of the optical system and making the imaging effect better.

[0017] In addition, by satisfying the relational characteristic 1.004<f / TTL<1.1, it is also beneficial for the optical system to obtain a longer focal length to have a telephoto characteristic, and it is also beneficial to compress the total length of the optical system so that the optical system has a relatively compact structure, thereby realizing a miniaturized design of the optical system. In addition, satisfying this relationship also helps the optical system to better process the details of distant scenes, making the details of the focused distant scenes more prominent, so as to achieve a good telephoto imaging effect, thereby allowing users to have a better shooting experience.

[0018] In one embodiment, the optical system satisfies the relationship:

[0019] 1.09<2*Imgh / TTL<1.2;

[0020] Imgh is half of the image height corresponding to the maximum field angle of the optical system. The optical system with the above-mentioned refractive power and surface design can further achieve the telephoto shooting effect by further satisfying the relationship condition. In addition, it can also make the optical system have a larger image plane size while maintaining miniaturization, thereby helping to have a large image plane characteristic, and then better present the shooting details of the distant view, thereby improving the distant shooting performance of the optical system.

[0021] In one embodiment, the optical system satisfies the relationship:

[0022] 1<f123 / R12<1.8;

[0023] f123 is the combined focal length of the first lens, the second lens and the third lens, and R12 is the radius of curvature of the image side surface of the first lens at the optical axis. When this relationship is satisfied, the combined effective focal length of the first lens, the second lens and the third lens and the radius of curvature of the image side surface of the first lens can be reasonably configured. On the one hand, the positive refractive power strength of the lens group composed of the first three lenses in the optical system can be reasonably controlled, and the image side surface shape of the first lens can be matched to make the incident light well regulated when entering the optical system, thereby effectively reducing the air gap between each adjacent lens in the optical system, thereby reducing the total length of the system; on the other hand, it is also helpful to control the image side surface shape of the first lens, thereby balancing the aberration generated by the image side lens. When the upper limit of the above relationship range is exceeded, the radius of curvature of the image side surface of the first lens is too small, resulting in the gap between the image side surface shape and the second lens being too small due to excessive curvature, which not only increases the difficulty of lens processing and molding, but also makes it difficult to assemble the lenses. In addition, it is easy to cause the refractive power to be too concentrated on the first lens, increasing the tolerance sensitivity of the first lens. When it is below the lower limit of the above relationship range, the radius of curvature of the image side surface of the first lens is too large, resulting in the surface shape being too flat, which is not conducive to correcting the spherical aberration, coma and astigmatism generated by the two lenses.

[0024] In one embodiment, the optical system satisfies the relationship:

[0025] -2.2<f567 / f<-0.9;

[0026] f567 is the combined focal length of the fifth lens, the sixth lens and the seventh lens. When this relationship is satisfied, the ratio of the combined focal length of the fifth lens, the sixth lens and the seventh lens to the total effective focal length of the optical system is controlled within a reasonable range, which is conducive to balancing the spherical aberration and chromatic aberration generated by the object lens, and can effectively avoid the excessive concentration of the refractive power intensity of the optical system in the rear lens group by reasonably adjusting the combined refractive power intensity of the fifth lens to the seventh lens, thereby improving the aberration correction ability of the system. At the same time, when this relationship is satisfied, the length of the optical system can be effectively reduced, and the telephoto characteristics of the optical system can be highlighted. When the upper limit of the above relationship is exceeded, the negative refractive power provided by the rear lens group composed of the fifth lens, the sixth lens and the seventh lens is too large, so that the refractive power of the optical system is excessively concentrated in the rear lens group, resulting in a decrease in the aberration correction ability of the system. When it is lower than the lower limit of the above relationship, the negative refractive power provided by the rear lens group composed of the fifth lens, the sixth lens and the seventh lens is insufficient to balance the positive refractive power of the front lens group, which is not conducive to the telephoto characteristics and large image surface characteristics.

[0027] In one embodiment, the optical system satisfies the relationship:

[0028] 1<f / f3<1.6;

[0029] f3 is the effective focal length of the third lens. When this relationship is satisfied, the total effective focal length of the optical system and the effective focal length of the third lens can be reasonably configured, so that the surface shape of the third lens is suitable, which not only helps to reduce the incident angle of light on the lens and reduce the tolerance sensitivity of the third lens, but also helps the optical system to have a telephoto characteristic. When it is higher than the upper limit of the above relationship, the positive refractive power contributed by the third lens is too strong, which is not conducive to the aberration balance with the front and rear lens groups, thereby affecting the image quality. When it is lower than the lower limit of the above relationship, the positive refractive power of the third lens is insufficient, and the aberrations generated by the front and rear lens groups are difficult to be adequately corrected, which ultimately leads to reduced image quality.

[0030] In one embodiment, the optical system satisfies the relationship:

[0031] 2.5<ct56 / et56<7;

[0032] ct56 is the distance from the image side of the fifth lens to the object side of the sixth lens on the optical axis, and et56 is the distance from the maximum effective aperture of the image side of the fifth lens to the maximum effective aperture of the object side of the sixth lens in the direction of the optical axis. When the above relationship is satisfied, the spacing between the fifth lens and the sixth lens on the optical axis and the spacing at the maximum effective diameter can be reasonably configured. On the one hand, it is beneficial to reduce the light deflection angle between the fifth lens and the sixth lens, thereby reducing the tolerance sensitivity of the two lenses; on the other hand, it is also beneficial to the assembly between the fifth lens and the sixth lens; in addition, it also helps to reduce the rear end size of the optical system. When it is higher than the upper limit of the above relationship, the edge gap between the fifth lens and the sixth lens is too small, and the edges of the two lenses are too close, increasing the risk of poor assembly.

[0033] In one embodiment, the optical system satisfies the relationship:

[0034] 0.4<|sag61| / et6<1.1;

[0035] sag61 is the sagittal height of the object side of the sixth lens at the maximum effective aperture, and et6 is the thickness of the sixth lens from the maximum effective aperture of the object side to the maximum effective aperture of the image side in the direction of the optical axis. When the above relationship is satisfied, the ratio between the sagittal height of the object side of the sixth lens at the maximum effective diameter and the edge thickness of the sixth lens can be reasonably configured, which, on the one hand, helps to control the inclination angle of the object side of the sixth lens at the edge, so that the surface shape from the center to the edge can be smoothly transitioned, so that the edge light can also be transitioned to the next lens at a gentle angle until the imaging surface; on the other hand, the edge thickness of the sixth lens can also be controlled within a reasonable range, which is conducive to controlling the thickness ratio of the entire lens so that it is not too large or too small, thereby reducing the difficulty of lens molding and assembly. When it is higher than the upper limit of the above relationship, the object side of the sixth lens is too curved, which is not conducive to molding and assembly. When it is lower than the lower limit of the above relationship, it is not conducive to the smooth transition of the edge light when passing through the sixth lens, resulting in insufficient illumination at the edge of the imaging surface, reducing the imaging quality.

[0036] In one embodiment, the optical system satisfies the relationship:

[0037] -3<sag71 / et7<-1;

[0038] sag71 is the sag height of the object side of the seventh lens at the maximum effective aperture, and et7 is the thickness of the seventh lens from the maximum effective aperture of the object side to the maximum effective aperture of the image side in the direction of the optical axis. When the above relationship is satisfied, the ratio between the sag height of the object side of the seventh lens at the maximum effective diameter and the edge thickness is controlled within a reasonable range, so that the opening angle of the seventh lens at the edge of the lens can be effectively controlled, so that the incident light can enter the seventh lens at a smaller incident angle and smoothly pass through the seventh lens to reach the imaging surface, which is conducive to the optical system to achieve a large image surface characteristic, thereby significantly improving the imaging quality. When it is lower than the lower limit of the above relationship, it is easy to cause the object side of the seventh lens to have a too steep profile, which is easy to produce recurve and increase the risk of ghost images; when it is higher than the upper limit of the above relationship, the edge thickness of the seventh lens is too large, which is easy to make the thickness ratio of the seventh lens too large, thereby making it difficult to form the lens.

[0039] In one embodiment, the optical system satisfies the relationship:

[0040] 14<f1 / CT1<23.5;

[0041] f1 is the effective focal length of the first lens, and CT1 is the thickness of the first lens on the optical axis. When this relationship is satisfied, a better ratio can be obtained between the refractive power strength and the center thickness of the first lens, thereby improving the feasibility of lens molding while correcting the aberration of the optical system.

[0042] A camera module includes 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 will have a telephoto characteristic, so that it can better process distant details and thus have excellent telephoto performance; at the same time, the length of the camera module can also be compressed to achieve a miniaturized design.

[0043] An electronic device comprises a fixing part and the camera module, wherein the camera module is arranged on the fixing part. The electronic device can assemble the camera module in a smaller space, and at the same time can obtain a good long-range shooting effect through the camera module. BRIEF DESCRIPTION OF THE DRAWINGS

[0044] Figure 1 A schematic diagram of the structure of an optical system provided in the first embodiment of the present application;

[0045] Figure 2 including a longitudinal spherical aberration diagram, an astigmatism diagram and a distortion diagram of the optical system in the first embodiment;

[0046] Figure 3 A schematic diagram of the structure of an optical system provided in the second embodiment of the present application;

[0047] Figure 4 including a longitudinal spherical aberration diagram, an astigmatism diagram and a distortion diagram of the optical system in the second embodiment;

[0048] Figure 5 A schematic diagram of the structure of an optical system provided in the third embodiment of the present application;

[0049] Figure 6 including a longitudinal spherical aberration diagram, an astigmatism diagram and a distortion diagram of the optical system in the third embodiment;

[0050] Figure 7 A schematic diagram of the structure of an optical system provided in a fourth embodiment of the present application;

[0051] Figure 8 including a longitudinal spherical aberration diagram, an astigmatism diagram and a distortion diagram of the optical system in the fourth embodiment;

[0052] Fig. 9 A schematic diagram of the structure of an optical system provided in a fifth embodiment of the present application;

[0053] Fig.10 including a longitudinal spherical aberration diagram, an astigmatism diagram and a distortion diagram of the optical system in the fifth embodiment;

[0054] Fig.11 A schematic diagram of the structure of an optical system provided in a sixth embodiment of the present application;

[0055] Fig.12 including a longitudinal spherical aberration diagram, an astigmatism diagram and a distortion diagram of the optical system in the sixth embodiment;

[0056] Fig.13 A schematic diagram of the structure of an optical system provided in the seventh embodiment of the present application;

[0057] Fig.14 including a longitudinal spherical aberration diagram, an astigmatism diagram and a distortion diagram of the optical system in the seventh embodiment;

[0058] Fig.15 A schematic diagram of the structure of an optical system provided in the eighth embodiment of the present application;

[0059] Fig.16 including a longitudinal spherical aberration diagram, an astigmatism diagram and a distortion diagram of the optical system in the eighth embodiment;

[0060] Fig.17 A schematic diagram of a camera module provided in one embodiment of the present application;

[0061] Fig.18 A schematic diagram of the structure of an electronic device provided in one embodiment of the present application. DETAILED DESCRIPTION

[0062] 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.

[0063] In the description of the present invention, it is necessary to understand that the terms "center", "longitudinal", "lateral", "length", "thickness", "top", "front", "rear", "axial", "radial" 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, rather than indicating or implying that the device or element referred to must have a specific orientation, be constructed and operated in a specific orientation, and therefore cannot be understood as a limitation on the present invention.

[0064] 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.

[0065] 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.

[0066] 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 an intermediate 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 an intermediate element at the same time.

[0067] refer to Figure 1 , an embodiment of the present application provides an optical system 10 with a seven-piece structure, and the optical system 10 includes a first lens L1, a second lens L2, a third lens L3, a fourth lens L4, a fifth lens L5, a sixth lens L6 and a seventh lens L7 in sequence from the object side to the image side along the optical axis 101. 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 101 of the optical system 10. The above-mentioned optical elements in the optical system 10 and the aperture not mentioned yet can be assembled with the lens barrel to form a camera lens.

[0068] 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 image sensor.

[0069] In the embodiment of the present application, the first lens L1 has positive refractive power, its object side surface S1 is convex at the near optical axis, and the image side surface S2 is concave at the near optical axis; the second lens L2 has negative refractive power, its object side surface S3 is convex at the near optical axis, and the image side surface S4 is concave at the near optical axis; the third lens L3 has positive refractive power, its object side surface S5 is convex at the near optical axis; the fourth lens L4 has positive refractive power or negative refractive power; the fifth lens L5 has positive refractive power or negative refractive power. The sixth lens L6 has positive or negative refractive power, and its image-side surface S12 is concave at the near optical axis. The seventh lens L7 has positive or negative refractive power, its object-side surface S13 is convex at the near optical axis, and its image-side surface S14 is concave at the near optical axis, and both its object-side surface S13 and image-side surface S14 are aspherical surfaces. In addition, at least one of its object-side surface S13 and image-side surface S14 has an inflection point.

[0070] In the above optical system 10, the refractive power and surface configuration of the first lens L1 are conducive to increasing the light input of the optical system and improving the image clarity. On the other hand, it is also conducive to increasing the field of view of the optical system and widening the shooting range. The front and rear lenses of the second lens L2 both have positive refractive power. By making the second lens L2 have the above refractive power and surface setting, it will be conducive to shortening the total length of the system and promoting the system to achieve aberration balance. The surface design of the third lens L3 is conducive to strengthening the strength of the positive refractive power, thereby facilitating the correction of the aberrations generated by the object lens. The design of the fifth lens L5 can also correct the aberrations such as astigmatism and distortion generated by the object lens. The design of the sixth lens L6 is conducive to shortening the total length of the system. The seventh lens L7 has the above surface design, which is conducive to the optical system 10 obtaining a larger image surface to match the image sensor with higher pixels. On the other hand, it can also increase the back focus of the optical system 10, thereby promoting the optical system 10 to have a sufficient safety distance during the module assembly process to avoid collision. On the other hand, the optical system 10 in the embodiment of the present application can, through the above-mentioned number of lenses, refractive power configuration and surface design, not only be advantageous in having a telephoto characteristic, but also be able to better balance the aberrations generated between the lenses, thereby suppressing the overall aberration of the optical system 10 and achieving a better imaging effect.

[0071] It should be noted that when the embodiments of the present application describe a surface of a lens as convex near the optical axis, it can be understood that the area of ​​the surface of the lens near the optical axis 101 is convex; when describing a surface of a lens as concave near the maximum effective aperture or near the circumference, it can be understood that the area of ​​the surface near the maximum effective aperture is concave. For example, when the surface is convex near the optical axis and also convex near the circumference, the shape of the surface from the center (at the optical axis 101) to the edge can be a pure convex surface; or it can first transition from a convex shape at the center to a concave shape, and then become convex when close to the maximum effective aperture. The definition of concave-convex features in the present application only refers to the surface shape of the effective light-transmitting area of ​​the corresponding lens surface.

[0072] In the embodiment of the present application, the optical system 10 also satisfies the following relationship conditions:

[0073] 1.004<f / TTL<1.1; f is the effective focal length 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 . TTL is also called the total optical length of the optical system 10 .

[0074] When the above relationship is satisfied, it is also beneficial for the optical system 10 to obtain a longer focal length to obtain a telephoto characteristic, and it is also beneficial to compress the total length of the optical system 10 so that the optical system 10 has a relatively compact structure, thereby realizing a miniaturized design of the optical system 10. In addition, when this relationship is satisfied, it is also helpful for the optical system 10 to better process the details of the distant scene, so that the details of the focused distant scene are more prominent, so as to achieve a good telephoto imaging effect, so that the user can obtain a better shooting experience. In some embodiments, the relationship satisfied by the optical system 10 can be specifically 1.01, 1.015, 1.02, 1.025, 1.045, 1.065, 1.078, 1.083, 1.086 or 1.09.

[0075] 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 technical effects can be achieved:

[0076] 1.09<2*Imgh / TTL<1.2; Imgh is half of the image height corresponding to the maximum field angle of the optical system 10. Imgh can also be understood as the diagonal length of the rectangular effective imaging area on the imaging surface S15. When the image sensor is assembled, Imgh can also be understood as the distance from the center to the diagonal edge of the rectangular effective pixel area of ​​the image sensor, and the diagonal direction of the above-mentioned effective imaging area is parallel to the diagonal direction of the rectangular effective pixel area. By further satisfying the relationship condition, on the one hand, it can help the optical system 10 to further achieve a telephoto shooting effect, and on the other hand, it can also enable the optical system 10 to have a larger image plane size while maintaining miniaturization, thereby helping to have a large image plane characteristic, and then better present the shooting details of the distant view, thereby improving the distant view shooting performance of the optical system 10. In some embodiments, the relationship satisfied by the optical system 10 can specifically be 1.095, 1.1, 1.11, 1.124, 1.136, 1.149, 1.158, 1.162 or 1.165.

[0077] 1<f123 / R12<1.8;f123 is the combined focal length of the first lens L1, the second lens L2 and the third lens L3, and R12 is the radius of curvature of the image side surface S2 of the first lens L1 at the optical axis. When this relationship is satisfied, the combined effective focal length of the first lens L1, the second lens L2 and the third lens L3 and the radius of curvature of the image side surface S2 of the first lens L1 can be reasonably configured. On the one hand, the positive refractive power strength of the lens group composed of the first three lenses in the optical system 10 can be reasonably controlled, and the surface shape of the image side surface S2 of the first lens L1 can be matched, so that the incident light can be well regulated when entering the optical system 10, thereby effectively reducing the air gap between each adjacent lens in the optical system 10, thereby reducing the total length of the system; on the other hand, it is also helpful to control the surface shape of the image side surface S2 of the first lens L1, so as to balance the aberrations generated by the image side lens. When the upper limit of the above relationship range is exceeded, the radius of curvature of the image side surface S2 of the first lens L1 is too small, resulting in the gap between the surface profile and the second lens L2 being too small due to excessive curvature, which not only increases the difficulty of lens processing and molding, but also makes it difficult to assemble the lenses. In addition, it is easy to cause the refractive power to be too concentrated on the first lens L1, increasing the tolerance sensitivity of the first lens L1. When the radius of curvature is lower than the lower limit of the above relationship range, the radius of curvature of the image side surface S2 of the first lens L1 is too large, resulting in the surface profile being too flat, which is not conducive to correcting the spherical aberration, coma and astigmatism generated by the two lenses. In some embodiments, the relationship satisfied by the optical system 10 can be 1.1, 1.13, 1.18, 1.25, 1.34, 1.43, 1.47 or 1.56.

[0078] -2.2<f567 / f<-0.9; f567 is the combined focal length of the fifth lens L5, the sixth lens L6 and the seventh lens L7. When this relationship is satisfied, the ratio of the combined focal length of the fifth lens L5, the sixth lens L6 and the seventh lens L7 to the total effective focal length of the optical system 10 is controlled within a reasonable range, which is conducive to balancing the spherical aberration and chromatic aberration generated by the object lens, and can effectively avoid the excessive concentration of the refractive power intensity of the optical system 10 on the rear lens group by reasonably adjusting the combined refractive power intensity of the fifth lens L5 to the seventh lens L7, thereby improving the aberration correction capability of the system. At the same time, when this relationship is satisfied, the length of the optical system 10 can be effectively reduced, while highlighting the telephoto characteristics of the optical system 10. When the upper limit of the above relationship is exceeded, the negative refractive power provided by the rear lens group composed of the fifth lens L5, the sixth lens L6 and the seventh lens L7 is too large, so that the refractive power of the optical system 10 is excessively concentrated on the rear lens group, resulting in a decrease in the aberration correction capability of the system. When it is lower than the lower limit of the above relationship, the negative refractive power provided by the rear lens group composed of the fifth lens L5, the sixth lens L6 and the seventh lens L7 is insufficient to balance the positive refractive power of the front lens group, which is not conducive to the telephoto characteristics and the large image plane characteristics. In some embodiments, the relationship satisfied by the optical system 10 can be specifically -2, -1.92, -1.85, -1.74, -1.53, -1.38, -1.2, -1.15, -1 or -0.95.

[0079] 1<f / f3<1.6; f3 is the effective focal length of the third lens L3. When this relationship is satisfied, the total effective focal length of the optical system 10 and the effective focal length of the third lens L3 can be reasonably configured, so that the surface shape of the third lens L3 is suitable, which not only helps to reduce the incident angle of the light on the lens and reduce the tolerance sensitivity of the third lens L3, but also helps the optical system 10 to have a telephoto characteristic. When it is higher than the upper limit of the above relationship, the positive refractive power contributed by the third lens L3 is too strong, which is not conducive to the aberration balance with the front and rear lens groups, thereby affecting the image quality. When it is lower than the lower limit of the above relationship, the positive refractive power of the third lens L3 is insufficient, and the aberrations generated by the front and rear lens groups are difficult to be sufficiently corrected, which ultimately leads to reduced image quality. In some embodiments, the relationship satisfied by the optical system 10 can be specifically 1.1, 1.14, 1.18, 1.26, 1.34, 1.46, 1.49, 1.53 or 1.57.

[0080] 2.5<ct56 / et56<7; ct56 is the distance from the image side surface S10 of the fifth lens L5 to the object side surface S11 of the sixth lens L6 on the optical axis, and et56 is the distance from the maximum effective aperture of the image side surface S10 of the fifth lens L5 to the maximum effective aperture of the object side surface S11 of the sixth lens L6 in the direction of the optical axis. When the above relationship is satisfied, the spacing between the fifth lens L5 and the sixth lens L6 on the optical axis and the spacing at the maximum effective diameter can be reasonably configured, which is beneficial to reduce the light deflection angle between the fifth lens L5 and the sixth lens L6 on the one hand, thereby reducing the tolerance sensitivity of the two lenses; on the other hand, it is also beneficial to the assembly between the fifth lens L5 and the sixth lens L6; in addition, it is also helpful to reduce the rear end size of the optical system 10. When it is higher than the upper limit of the above relationship, the edge gap between the fifth lens L5 and the sixth lens L6 is too small, and the edges of the two lenses are too close, increasing the risk of poor assembly. In some embodiments, the relationship satisfied by the optical system 10 may specifically be 3, 3.3, 3.8, 4.5, 5.2, 5.8, 6, 6.35 or 6.5.

[0081] 0.4<|sag61| / et6<1.1; sag61 is the sag height of the object side surface S11 of the sixth lens L6 at the maximum effective aperture, and et6 is the thickness from the object side surface S11 at the maximum effective aperture to the image side surface S12 at the maximum effective aperture in the direction of the optical axis of the sixth lens L6. It should be noted that the sag height of the lens surface at the maximum effective aperture is the distance from the intersection of the surface and the optical axis 101 to the maximum effective aperture in the direction parallel to the optical axis 101. When the above relationship is satisfied, the ratio between the sagittal height of the object side surface S11 of the sixth lens L6 at the maximum effective diameter and the edge thickness of the sixth lens L6 can be reasonably configured. On the one hand, it is helpful to control the inclination angle of the object side surface S11 of the sixth lens L6 at the edge, so that the surface shape from the center to the edge can be smoothly transitioned, so that the edge light can also be transitioned to the next lens at a gentle angle until the imaging surface S15; on the other hand, the edge thickness of the sixth lens L6 can be controlled within a reasonable range, which is conducive to controlling the thickness ratio of the entire lens so that it is not too large or too small, thereby reducing the difficulty of lens molding and assembly. When it is higher than the upper limit of the above relationship, the object side surface S11 of the sixth lens L6 is too curved, which is not conducive to molding and assembly. When it is lower than the lower limit of the above relationship, it is not conducive to the smooth transition of the edge light when passing through the sixth lens L6, resulting in insufficient illumination at the edge of the imaging surface S15, reducing the imaging quality. In some embodiments, the relationship satisfied by the optical system 10 may specifically be 0.5, 0.56, 0.64, 0.72, 0.81, 0.89, 0.94, 0.97 or 1.

[0082] -3<sag71 / et7<-1; sag71 is the sag height of the object side surface S13 of the seventh lens L7 at the maximum effective aperture, and et7 is the thickness from the maximum effective aperture of the object side surface S13 of the seventh lens L7 to the maximum effective aperture of the image side surface S14 in the direction of the optical axis. It should be noted that the sag height of the lens surface at the maximum effective aperture is the distance from the intersection of the surface and the optical axis 101 to the maximum effective aperture in the direction parallel to the optical axis 101. When the value of sag71 is negative, it indicates that the position of the maximum effective aperture of the object side surface S13 of the seventh lens L7 is closer to the object side than the position of the intersection of the surface and the optical axis 101. When the above relationship is satisfied, the ratio between the sagittal height and the edge thickness of the object side surface S13 of the seventh lens L7 at the maximum effective diameter is controlled within a reasonable range, so that the opening angle of the seventh lens at the edge of the lens can be effectively controlled, so that the incident light can enter the seventh lens L7 at a smaller incident angle and smoothly pass through the seventh lens L7 to reach the imaging surface S15, which is conducive to the optical system 10 to achieve a large image surface characteristic, thereby significantly improving the imaging quality. When it is lower than the lower limit of the above relationship, it is easy to cause the surface shape of the object side surface S13 of the seventh lens L7 to be too steep, which is easy to produce backbends and increase the risk of ghost images; when it is higher than the upper limit of the above relationship, the edge thickness of the seventh lens L7 is too large, which is easy to make the thickness ratio of the seventh lens L7 too large, thereby causing difficulty in lens molding. In some embodiments, the relationship satisfied by the optical system 10 can be specifically -2.4, -2.2, -2, -1.84, -1.67, -1.55, -1.32, -1.26 or -1.2.

[0083] 14<f1 / CT1<23.5; f1 is the effective focal length of the first lens L1, and CT1 is the thickness of the first lens L1 on the optical axis. When this relationship is satisfied, a better ratio can be obtained between the refractive power strength and the center thickness of the first lens L1, so that the feasibility of lens molding can be improved while correcting the aberration of the optical system 10. In some embodiments, the relationship satisfied by the optical system 10 can be 14.5, 15.3, 15.8, 16.7, 18.2, 19.5, 20.7, 21.6, 22.5 or 23.

[0084] The reference wavelength of the parameters related to the focal length in the above relationship conditions is 555nm, and the reference wavelength of the parameters related to the refractive index and the Abbe number is 587.6nm, that is, the wavelength of d light. In addition, the above focal length parameters at least represent the focal length of the corresponding lens at the near optical axis.

[0085] The above relationship conditions and the technical effects brought about are for the seven-lens optical system 10 with the above lens design. When the lens design (number of lenses, refractive power configuration, surface configuration, etc.) of the above optical system 10 cannot be ensured, it will be difficult to ensure that the optical system 10 can still have the corresponding technical effects when these relationship conditions are met, and there is even the possibility that the camera performance will be significantly reduced.

[0086] The optical system 10 includes an aperture stop STO, which is used to control the amount of light entering the optical system 10 and can also block ineffective light. The aperture stop STO can be arranged on the object side of the first lens L1, or between two adjacent lenses from the first lens L1 to the seventh lens L7. The aperture stop STO can be formed by a lens barrel structure that clamps the lens, or it can be a gasket that is separately assembled between the lens and the lens barrel.

[0087] In some embodiments, the object side surface and / or image side surface of at least one of the first lens L1 to the seventh lens L7 is an aspheric surface, that is, at least one of the first lens L1 to the seventh lens L7 has an aspheric surface shape. For example, the object side surface and the image side surface of the first lens L1 to the seventh lens L7 can be designed as aspheric surfaces. The aspheric surface shape setting can further help the optical system 10 eliminate aberrations, and 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 the miniaturization design. Of course, in other embodiments, the object side surface and / or image side surface of at least one of the first lens L1 to the seventh lens L7 can also be a spherical surface. It should be noted that the actual surface shape of the lens is not limited to the shape of the spherical or aspheric surface shown in the accompanying drawings, which are only for example reference and not strictly drawn to scale. It should also be noted that when the object side surface or the image side surface of a lens is an aspheric surface, the surface can be a structure that is convex as a whole or concave as a whole. In some embodiments, the surface may also be designed to have an inflection point. In this case, the surface shape from the center to the edge will change. For example, the surface is convex near the optical axis and concave near the circumference.

[0088] The calculation of the aspheric surface can refer to the aspheric surface formula:

[0089]

[0090] Among them, Z is the distance from the corresponding point on the aspheric surface to the tangent plane of the surface at the optical axis, r is the distance from the corresponding point on the aspheric surface to the optical axis, c is the curvature of the aspheric surface at the optical axis, k is the cone coefficient, and Ai is the coefficient of the high-order term corresponding to the i-th high-order term in the aspheric surface shape formula.

[0091] On the other hand, 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. Lenses made of plastic can reduce the weight of the optical system 10 and reduce production costs, while lenses made of glass can withstand higher temperatures and have excellent optical effects. In some embodiments, at least one of the first lens L1 to the seventh lens L7 is made of plastic, and at least one is made of glass. The material configuration relationship of the lenses 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. In some embodiments, the plastic material can specifically be polycarbonate.

[0092] In some embodiments, the optical system 10 further includes an infrared cut-off filter 110, which is disposed on the image side of the seventh lens L7 and 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 the infrared light from reaching the imaging surface S15 of the optical system 10, thereby preventing the 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, and the infrared cut-off filter 110 can be installed between the optical system 10 and the image sensor when the optical system 10 and the image sensor are assembled. 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.

[0093] Next, the optical system 10 of the present application is described with more specific and detailed embodiments:

[0094] First embodiment

[0095] refer to Figure 1 and Figure 2 In the first embodiment, the optical system 10 includes, from the object side to the image side along the optical axis 101, 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 STO, 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 negative refractive power. Figure 2 The longitudinal spherical aberration diagram, astigmatism diagram and distortion diagram of the optical system 10 in the first embodiment are included, and the reference wavelength of the astigmatism diagram and the distortion diagram in the following embodiments is 555 nm.

[0096] The object-side surface S1 of the first lens L1 is convex near the optical axis, and the image-side surface S2 is concave near the optical axis; the object-side surface S1 is convex near the circumference, and the image-side surface S2 is concave near the circumference.

[0097] The object-side surface S3 of the second lens L2 is convex near the optical axis, and the image-side surface S4 is concave near the optical axis; the object-side surface S3 is convex near the circumference, and the image-side surface S4 is convex near the circumference.

[0098] The object-side surface S5 of the third lens L3 is convex near the optical axis, and the image-side surface S6 is concave near the optical axis; the object-side surface S5 is convex near the circumference, and the image-side surface S6 is concave near the circumference.

[0099] The object-side surface S7 of the fourth lens L4 is concave at the near optical axis, and the image-side surface S8 is convex at the near optical axis; the object-side surface S7 is concave near the circumference, and the image-side surface S8 is convex near the circumference.

[0100] The object-side surface S9 of the fifth lens L5 is concave at the near optical axis, and the image-side surface S10 is convex at the near optical axis; the object-side surface S9 is concave near the circumference, and the image-side surface S10 is concave near the circumference.

[0101] The object-side surface S11 of the sixth lens L6 is convex near the optical axis, and the image-side surface S12 is concave near the optical axis; the object-side surface S11 is concave near the circumference, and the image-side surface S12 is concave near the circumference.

[0102] The object-side surface S13 of the seventh lens L7 is convex near the optical axis, and the image-side surface S14 is concave near the optical axis; the object-side surface S13 is convex near the circumference, and the image-side surface S14 is concave near the circumference.

[0103] In the above optical system 10, the refractive power and surface configuration of the first lens L1 are conducive to increasing the light input of the optical system and improving the image clarity. On the other hand, it is also conducive to increasing the field of view of the optical system and widening the shooting range. The front and rear lenses of the second lens L2 both have positive refractive power. By making the second lens L2 have the above refractive power and surface setting, it will be conducive to shortening the total length of the system and promoting the system to achieve aberration balance. The surface design of the third lens L3 is conducive to strengthening the strength of the positive refractive power, thereby facilitating the correction of the aberrations generated by the object lens. The design of the fifth lens L5 can also correct the aberrations such as astigmatism and distortion generated by the object lens. The design of the sixth lens L6 is conducive to shortening the total length of the system. The seventh lens L7 has the above surface design, which is conducive to the optical system 10 obtaining a larger image surface to match the image sensor with higher pixels. On the other hand, it can also increase the back focus of the optical system 10, thereby promoting the optical system 10 to have a sufficient safety distance during the module assembly process to avoid collision. The refractive power and surface shape of each lens distributed from the object side to the image side are reasonably matched, which is beneficial to having a telephoto characteristic on the one hand, and can also better balance the aberrations generated between the lenses on the other hand, thereby suppressing the overall aberration of the optical system 10 and making the imaging effect better.

[0104] The lens parameters of the optical system 10 in this embodiment are given in the following Tables 1 and 2. Table 2 shows the aspheric coefficients of the corresponding lens surfaces in Table 1, where K is the cone coefficient and Ai is the coefficient corresponding to the i-th order high-order term in the aspheric surface formula. The elements from the object side to the image side of the optical system 10 are arranged in order from top to bottom in accordance with Table 1. The stop in the table is the aperture stop STO. The surfaces corresponding to the surface numbers S1 and S2 represent the object side surface S1 and the image side surface S2 of the first lens L1, respectively, that is, in the same lens, the surface with a smaller surface number is the object side surface, and the surface with a larger surface number is the image side surface. The Y radius is the radius of curvature of the corresponding surface of the lens at 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 of the lens to the surface of the next optical element (such as the object side or aperture surface of the next lens) on the optical axis. The value of the aperture in the "Thickness" parameter represents the distance from the aperture surface to the object side of the next optical element on the optical axis. In the parameter tables of the following embodiments (the first to the eighth embodiments), the reference wavelengths of the refractive index and Abbe number of each lens are 587.6nm, the reference wavelength of the focal length is 555nm, and the numerical units of the Y radius, thickness, and focal length (effective focal length) are all millimeters (mm). In addition, the relationship calculations and lens structures of each embodiment shall be based on the data provided in the parameter tables (such as Table 1, Table 2, Table 3, Table 4, etc.).

[0105] Table 1

[0106]

[0107] As can be seen from Table 1, the effective focal length f of the optical system 10 is 7.75 mm, the aperture number FNO is 2.60, the maximum field of view FOV is 43.57°, and the total optical length TTL is 7.69 mm. The rectangular effective pixel area of ​​the image sensor has a diagonal direction. When the image sensor is assembled, the FOV can also be understood as the maximum field of view of the optical system 10 parallel to the diagonal direction.

[0108] In addition, it can be seen that the materials of the first lens L1, the second lens L2, the fourth lens L4 and the fifth lens L5 are all glass, the materials of the third lens L3, the sixth lens L6 and the seventh lens L7 are all plastic, and the object-side surface and the image-side surface of each lens in the optical system 10 are aspherical surfaces.

[0109] Table 2

[0110] Surface number S1 S2 S3 S4 S5 S6 S7 K 5.565E-01 6.407E+00 -1.512E+00 -1.039E+00 -2.906E+00 9.900E+01 6.878E+01 A4 -3.270E-03 -4.421E-02 -9.650E-02 -7.823E-02 2.266E-02 2.043E-02 -9.300E-03 A6 -4.200E-03 4.707E-02 7.477E-02 1.063E-01 7.039E-02 -3.410E-03 -1.836E-02 A8 3.320E-03 -1.812E-02 -1.564E-02 -1.461E-01 -1.654E-01 -2.500E-02 -1.933E-02 A10 -1.570E-03 3.740E-03 -8.670E-03 1.609E-01 1.990E-01 3.395E-02 6.054E-02 A12 5.800E-04 -4.700E-04 6.560E-03 -1.048E-01 -1.269E-01 -1.999E-02 -6.690E-02 A14 -1.600E-04 4.000E-05 -1.910E-03 3.888E-02 4.574E-02 6.290E-03 4.213E-02 A16 3.000E-05 0.000E+00 3.000E-04 -8.190E-03 -9.410E-03 -1.090E-03 -1.578E-02 A18 0.000E+00 0.000E+00 -2.000E-05 9.200E-04 1.030E-03 1.000E-04 3.210E-03 A20 0.000E+00 0.000E+00 0.000E+00 -4.000E-05 -5.000E-05 0.000E+00 -2.700E-04 Surface number S8 S9 S10 S11 S12 S13 S14 K -9.900E+01 -2.288E+01 -2.967E+01 -7.561E+01 6.657E+00 1.100E+01 -2.244E+01 A4 -2.139E-02 3.560E-03 -2.665E-02 -7.859E-02 -8.283E-02 -1.902E-01 -1.042E-01 A6 -3.210E-03 1.652E-02 5.095E-02 3.356E-02 4.973E-02 8.672E-02 3.872E-02 A8 -4.544E-02 -7.081E-02 -1.157E-01 -5.517E-02 -4.987E-02 -3.540E-02 -9.900E-03 A10 1.018E-01 1.251E-01 1.600E-01 3.353E-02 3.061E-02 8.530E-03 -5.700E-04 A12 -1.045E-01 -1.142E-01 -1.228E-01 -7.100E-04 -1.121E-02 -1.960E-03 1.330E-03 A14 5.968E-02 6.234E-02 5.695E-02 -8.530E-03 2.470E-03 6.700E-04 -4.600E-04 A16 -1.911E-02 -2.049E-02 -1.578E-02 3.950E-03 -3.100E-04 -1.500E-04 8.000E-05 A18 3.190E-03 3.670E-03 2.380E-03 -7.200E-04 2.000E-05 1.000E-05 -1.000E-05 A20 -2.100E-04 -2.700E-04 -1.500E-04 5.000E-05 0.000E+00 0.000E+00 0.000E+00

[0111] In the first embodiment, the optical system 10 also satisfies the following relationships:

[0112] f / TTL=1.009; f is the effective focal length 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, it is beneficial for the optical system 10 to obtain a longer focal length to obtain a telephoto characteristic, and it is also beneficial to compress the total length of the optical system 10 so that the optical system 10 has a relatively compact structure, thereby realizing a miniaturized design of the optical system 10. In addition, when this relationship is satisfied, it is also helpful for the optical system 10 to better process the details of the distant scene, so that the details of the focused distant scene are more prominent, so as to achieve a good telephoto imaging effect, so that the user can have a better shooting experience.

[0113] 2*Imgh / TTL=1.092; Imgh is half of the image height corresponding to the maximum field angle of the optical system 10. By further satisfying this relationship, on the one hand, it can help the optical system 10 to further achieve a telephoto shooting effect, and on the other hand, it can also enable the optical system 10 to have a larger image plane size while maintaining miniaturization, thereby helping to have a large image plane characteristic, and further being able to better present the shooting details of the distant view, thereby improving the distant view shooting performance of the optical system 10.

[0114] f123 / R12=1.08;f123 is the combined focal length of the first lens L1, the second lens L2 and the third lens L3, and R12 is the radius of curvature of the image side surface S2 of the first lens L1 at the optical axis. When this relationship is satisfied, on the one hand, the positive refractive power strength of the lens group composed of the first three lenses in the optical system 10 can be reasonably controlled, and the surface shape of the image side surface S2 of the first lens L1 can be matched, so that the incident light can be well regulated when entering the optical system 10, thereby effectively reducing the air gap between each adjacent lens in the optical system 10, thereby reducing the total length of the system; on the other hand, it is also helpful to control the surface shape of the image side surface S2 of the first lens L1, so as to balance the aberrations generated by the image side lens.

[0115] f567 / f=-0.96; f567 is the combined focal length of the fifth lens L5, the sixth lens L6 and the seventh lens L7. When this relationship is satisfied, it is beneficial to balance the spherical aberration and chromatic aberration generated by the object lens, and can effectively avoid the excessive concentration of the refractive power intensity of the optical system 10 on the rear lens group, thereby improving the aberration correction capability of the system. At the same time, when this relationship is satisfied, the length of the optical system 10 can be effectively reduced, while highlighting the telephoto characteristics of the optical system 10.

[0116] f / f3=1.28; f3 is the effective focal length of the third lens L3. When this relationship is satisfied, the total effective focal length of the optical system 10 and the effective focal length of the third lens L3 can be reasonably configured, so that the surface shape of the third lens L3 is appropriate, which not only helps to reduce the incident angle of light on the lens and reduce the tolerance sensitivity of the third lens L3, but also helps the optical system 10 to have a telephoto characteristic.

[0117] ct56 / et56=4.18; ct56 is the distance on the optical axis from the image side surface S10 of the fifth lens L5 to the object side surface S11 of the sixth lens L6, and et56 is the distance on the optical axis from the maximum effective aperture of the image side surface S10 of the fifth lens L5 to the maximum effective aperture of the object side surface S11 of the sixth lens L6. When the above relationship is satisfied, the spacing on the optical axis and the spacing at the maximum effective diameter between the fifth lens L5 and the sixth lens L6 can be reasonably configured, which is beneficial to reduce the light deflection angle between the fifth lens L5 and the sixth lens L6, thereby reducing the tolerance sensitivity of the two lenses; on the other hand, it is also beneficial to the assembly between the fifth lens L5 and the sixth lens L6; in addition, it also helps to reduce the rear end size of the optical system 10.

[0118] |sag61| / et6=0.456; sag61 is the sag height of the object side surface S11 of the sixth lens L6 at the maximum effective aperture, and et6 is the thickness of the sixth lens L6 from the object side surface S11 at the maximum effective aperture to the image side surface S12 at the maximum effective aperture in the optical axis direction. When the above relationship is satisfied, on the one hand, it helps to control the inclination angle of the object side surface S11 of the sixth lens L6 at the edge, so that the surface shape from the center to the edge can be smoothly transitioned, so that the edge light can also be transitioned to the next lens at a gentle angle until the imaging surface S15; on the other hand, it can also control the edge thickness of the sixth lens L6 within a reasonable range, which is conducive to controlling the thickness ratio of the entire lens so that it is not too large or too small, thereby reducing the difficulty of lens molding and assembly.

[0119] sag71 / et7=-1.82; sag71 is the sag height of the object side surface S13 of the seventh lens L7 at the maximum effective aperture, and et7 is the thickness of the seventh lens L7 from the maximum effective aperture of the object side surface S13 to the maximum effective aperture of the image side surface S14 in the optical axis direction. When the above relationship is satisfied, the opening angle of the seventh lens at the edge of the lens can be effectively controlled, so that the incident light can enter the seventh lens L7 at a smaller incident angle and smoothly pass through the seventh lens L7 to reach the imaging surface S15, which is conducive to enabling the optical system 10 to achieve a large image surface characteristic, thereby significantly improving the imaging quality.

[0120] f1 / CT1=16.08; f1 is the effective focal length of the first lens L1, and CT1 is the thickness of the first lens L1 on the optical axis. When this relationship is satisfied, a better ratio can be obtained between the refractive power strength and the center thickness of the first lens L1, thereby improving the feasibility of lens molding while correcting the aberration of the optical system 10.

[0121] 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 2Also included is a field curvature diagram (Astigmatic Field Curves) of the optical system 10, where the S curve represents the sagittal field curvature at 555nm, and the T curve represents the meridian field curvature at 555nm. As can be seen from the figure, the field curvature of the optical system is small, the field curvature and astigmatism of each field of view are well corrected, and the center and edge of the field of view have clear imaging. Figure 2 The optical system 10 also includes a distortion diagram (Distortion). As can be seen from the diagram, the image deformation caused by the main light beam is small, and the maximum distortion is controlled within 2.5%. Therefore, it can be judged that the imaging quality of the optical system 10 is excellent.

[0122] Second embodiment

[0123] refer to Figure 3 and Figure 4 In the second embodiment, the optical system 10 includes, from the object side to the image side along the optical axis 101, 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 STO, 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 negative refractive power. Figure 4 Included are diagrams of longitudinal spherical aberration, astigmatism, and distortion of the optical system 10 in the second embodiment.

[0124] The object-side surface S1 of the first lens L1 is convex near the optical axis, and the image-side surface S2 is concave near the optical axis; the object-side surface S1 is convex near the circumference, and the image-side surface S2 is concave near the circumference.

[0125] The object-side surface S3 of the second lens L2 is convex near the optical axis, and the image-side surface S4 is concave near the optical axis; the object-side surface S3 is convex near the circumference, and the image-side surface S4 is convex near the circumference.

[0126] The object-side surface S5 of the third lens L3 is convex near the optical axis, and the image-side surface S6 is convex near the optical axis; the object-side surface S5 is convex near the circumference, and the image-side surface S6 is concave near the circumference.

[0127] The object-side surface S7 of the fourth lens L4 is concave at the near optical axis, and the image-side surface S8 is convex at the near optical axis; the object-side surface S7 is concave near the circumference, and the image-side surface S8 is convex near the circumference.

[0128] The object-side surface S9 of the fifth lens L5 is concave at the near optical axis, and the image-side surface S10 is convex at the near optical axis; the object-side surface S9 is concave near the circumference, and the image-side surface S10 is concave near the circumference.

[0129] The object-side surface S11 of the sixth lens L6 is convex near the optical axis, and the image-side surface S12 is concave near the optical axis; the object-side surface S11 is concave near the circumference, and the image-side surface S12 is concave near the circumference.

[0130] The object-side surface S13 of the seventh lens L7 is convex near the optical axis, and the image-side surface S14 is concave near the optical axis; the object-side surface S13 is convex near the circumference, and the image-side surface S14 is concave near the circumference.

[0131] 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 component names and parameters can be obtained from the first embodiment and are not repeated here.

[0132] Table 3

[0133]

[0134] Table 4

[0135] Surface number S1 S2 S3 S4 S5 S6 S7 K 3.472E-01 4.415E+00 -9.897E-01 -8.015E-01 -1.812E+00 -9.900E+01 9.900E+01 A4 -4.140E-03 -4.884E-02 -9.174E-02 -7.528E-02 6.100E-03 1.809E-02 -3.105E-02 A6 -3.710E-03 4.772E-02 7.609E-02 8.432E-02 5.718E-02 -1.524E-02 5.680E-03 A8 3.320E-03 -1.821E-02 -2.236E-02 -9.632E-02 -1.290E-01 2.884E-02 -5.546E-02 A10 -1.960E-03 3.760E-03 -2.820E-03 1.047E-01 1.755E-01 -4.880E-02 1.386E-01 A12 8.000E-04 -4.700E-04 4.400E-03 -6.541E-02 -1.246E-01 4.990E-02 -1.771E-01 A14 -2.300E-04 4.000E-05 -1.540E-03 2.250E-02 5.090E-02 -2.806E-02 1.337E-01 A16 4.000E-05 0.000E+00 2.700E-04 -4.310E-03 -1.221E-02 8.540E-03 -5.886E-02 A18 0.000E+00 0.000E+00 -2.000E-05 4.300E-04 1.600E-03 -1.320E-03 1.373E-02 A20 0.000E+00 0.000E+00 0.000E+00 -2.000E-05 -9.000E-05 8.000E-05 -1.300E-03 Surface number S8 S9 S10 S11 S12 S13 S14 K -9.900E+01 1.694E+01 -3.402E+01 4.728E+01 5.653E+00 1.100E+01 -1.840E+01 A4 -4.560E-02 8.790E-03 1.110E-02 -5.535E-02 -9.082E-02 -1.804E-01 -8.680E-02 A6 1.131E-02 -2.250E-03 3.150E-03 4.588E-02 9.189E-02 8.337E-02 3.182E-02 A8 -4.579E-02 -5.998E-02 -7.625E-02 -9.462E-02 -1.039E-01 -3.707E-02 -9.160E-03 A10 9.186E-02 1.101E-01 1.027E-01 6.435E-02 6.885E-02 1.334E-02 9.900E-04 A12 -9.170E-02 -9.080E-02 -5.634E-02 -1.307E-02 -2.763E-02 -4.870E-03 3.200E-04 A14 5.198E-02 4.392E-02 1.328E-02 -4.770E-03 6.890E-03 1.490E-03 -1.600E-04 A16 -1.661E-02 -1.278E-02 2.500E-04 2.920E-03 -1.040E-03 -2.700E-04 3.000E-05 A18 2.760E-03 2.030E-03 -7.200E-04 -5.400E-04 9.000E-05 2.000E-05 0.000E+00 A20 -1.900E-04 -1.300E-04 1.000E-04 3.000E-05 0.000E+00 0.000E+00 0.000E+00

[0136] The optical system 10 in this embodiment satisfies the following relationship:

[0137]

[0138]

[0139] 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, wherein the meridian field curvature and sagittal field curvature are controlled within 0.05 mm, and the maximum distortion is controlled within 2.5%, so that the optical system 10 of this embodiment has excellent imaging quality.

[0140] Third embodiment

[0141] refer to Figure 5 and Figure 6 In the third embodiment, the optical system 10 includes, from the object side to the image side along the optical axis 101, 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 STO, a fourth lens L4 with positive refractive power, a fifth lens L5 with positive refractive power, a sixth lens L6 with negative refractive power, and a seventh lens L7 with negative refractive power. Figure 6 Included are diagrams of longitudinal spherical aberration, astigmatism, and distortion of the optical system 10 in the third embodiment.

[0142] The object-side surface S1 of the first lens L1 is convex near the optical axis, and the image-side surface S2 is concave near the optical axis; the object-side surface S1 is convex near the circumference, and the image-side surface S2 is concave near the circumference.

[0143] The object-side surface S3 of the second lens L2 is convex near the optical axis, and the image-side surface S4 is concave near the optical axis; the object-side surface S3 is convex near the circumference, and the image-side surface S4 is concave near the circumference.

[0144] The object-side surface S5 of the third lens L3 is convex near the optical axis, and the image-side surface S6 is concave near the optical axis; the object-side surface S5 is convex near the circumference, and the image-side surface S6 is concave near the circumference.

[0145] The object-side surface S7 of the fourth lens L4 is convex at the near optical axis, and the image-side surface S8 is concave at the near optical axis; the object-side surface S7 is concave near the circumference, and the image-side surface S8 is concave near the circumference.

[0146] The object-side surface S9 of the fifth lens L5 is concave at the near optical axis, and the image-side surface S10 is convex at the near optical axis; the object-side surface S9 is concave near the circumference, and the image-side surface S10 is concave near the circumference.

[0147] The object-side surface S11 of the sixth lens L6 is convex near the optical axis, and the image-side surface S12 is concave near the optical axis; the object-side surface S11 is concave near the circumference, and the image-side surface S12 is concave near the circumference.

[0148] The object-side surface S13 of the seventh lens L7 is convex near the optical axis, and the image-side surface S14 is concave near the optical axis; the object-side surface S13 is convex near the circumference, and the image-side surface S14 is concave near the circumference.

[0149] 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 component names and parameters can be obtained from the first embodiment and are not repeated here.

[0150] Table 5

[0151]

[0152]

[0153] Table 6

[0154] Surface number S1 S2 S3 S4 S5 S6 S7 K 2.926E-01 3.604E+00 -1.007E+00 -7.026E-01 -1.372E+00 8.365E+01 -9.900E+01 A4 -4.860E-03 -6.343E-02 -9.836E-02 -5.648E-02 2.011E-02 6.500E-03 -4.422E-02 A6 -3.240E-03 5.533E-02 7.317E-02 5.446E-02 3.162E-02 -1.178E-02 2.632E-02 A8 3.270E-03 -2.012E-02 -1.006E-02 -7.243E-02 -1.153E-01 3.005E-02 -1.020E-01 A10 -2.420E-03 4.020E-03 -1.451E-02 9.286E-02 1.747E-01 -4.689E-02 2.328E-01 A12 1.230E-03 -4.900E-04 1.023E-02 -6.089E-02 -1.255E-01 4.503E-02 -3.004E-01 A14 -4.000E-04 4.000E-05 -3.210E-03 2.111E-02 5.096E-02 -2.397E-02 2.313E-01 A16 8.000E-05 0.000E+00 5.500E-04 -4.020E-03 -1.213E-02 6.900E-03 -1.042E-01 A18 -1.000E-05 0.000E+00 -5.000E-05 4.000E-04 1.580E-03 -1.010E-03 2.496E-02 A20 0.000E+00 0.000E+00 0.000E+00 -2.000E-05 -9.000E-05 6.000E-05 -2.440E-03 Surface number S8 S9 S10 S11 S12 S13 S14 K 9.900E+01 -1.001E+01 -2.331E+01 6.571E+00 5.004E+00 1.088E+01 -1.897E+01 A4 -4.841E-02 9.100E-04 7.800E-04 -3.778E-02 -5.243E-02 -1.821E-01 -1.039E-01 A6 1.759E-02 -4.920E-03 -1.935E-02 -1.622E-02 3.468E-02 7.978E-02 4.194E-02 A8 -4.246E-02 -1.811E-02 -2.930E-03 -2.670E-02 -6.050E-02 -2.693E-02 -1.318E-02 A10 7.769E-02 5.853E-02 2.865E-02 2.776E-02 4.842E-02 2.770E-03 1.470E-03 A12 -7.579E-02 -6.105E-02 -1.769E-02 -4.800E-03 -2.171E-02 -2.000E-05 5.100E-04 A14 4.235E-02 3.417E-02 1.420E-03 -4.390E-03 5.850E-03 4.300E-04 -2.500E-04 A16 -1.331E-02 -1.090E-02 2.390E-03 2.380E-03 -9.400E-04 -1.700E-04 5.000E-05 A18 2.170E-03 1.840E-03 -9.100E-04 -4.500E-04 8.000E-05 2.000E-05 -1.000E-05 A20 -1.400E-04 -1.300E-04 1.000E-04 3.000E-05 0.000E+00 0.000E+00 0.000E+00

[0155] The optical system 10 in this embodiment satisfies the following relationship:

[0156] f / TTL 1.020 ct56 / et56 5.62 2*Imgh / TTL 1.094 |sag61| / et6 0.516 f123 / R12 1.53 sag71 / et7 -1.98 f567 / f -1.02 f1 / CT1 14.33 f / f3 1.09

[0157] Depend on Figure 6As 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, wherein the meridian field curvature and sagittal field curvature are controlled within 0.025 mm, and the maximum distortion is controlled at about 2.5%, so that the imaging quality of the optical system 10 is excellent.

[0158] Fourth embodiment

[0159] refer to Figure 7 and Figure 8 In the fourth embodiment, the optical system 10 includes, from the object side to the image side along the optical axis 101, 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 STO, a fourth lens L4 with negative refractive power, a fifth lens L5 with positive refractive power, a sixth lens L6 with positive refractive power, and a seventh lens L7 with negative refractive power. Figure 8 Included are diagrams of longitudinal spherical aberration, astigmatism, and distortion of the optical system 10 in the fourth embodiment.

[0160] The object-side surface S1 of the first lens L1 is convex near the optical axis, and the image-side surface S2 is concave near the optical axis; the object-side surface S1 is convex near the circumference, and the image-side surface S2 is concave near the circumference.

[0161] The object-side surface S3 of the second lens L2 is convex near the optical axis, and the image-side surface S4 is concave near the optical axis; the object-side surface S3 is convex near the circumference, and the image-side surface S4 is concave near the circumference.

[0162] The object-side surface S5 of the third lens L3 is convex near the optical axis, and the image-side surface S6 is concave near the optical axis; the object-side surface S5 is convex near the circumference, and the image-side surface S6 is concave near the circumference.

[0163] The object-side surface S7 of the fourth lens L4 is convex at the near optical axis, and the image-side surface S8 is concave at the near optical axis; the object-side surface S7 is concave near the circumference, and the image-side surface S8 is concave near the circumference.

[0164] The object-side surface S9 of the fifth lens L5 is convex near the optical axis, and the image-side surface S10 is convex near the optical axis; the object-side surface S9 is convex near the circumference, and the image-side surface S10 is convex near the circumference.

[0165] The object-side surface S11 of the sixth lens L6 is convex near the optical axis, and the image-side surface S12 is concave near the optical axis; the object-side surface S11 is concave near the circumference, and the image-side surface S12 is concave near the circumference.

[0166] The object-side surface S13 of the seventh lens L7 is convex near the optical axis, and the image-side surface S14 is concave near the optical axis; the object-side surface S13 is convex near the circumference, and the image-side surface S14 is concave near the circumference.

[0167] 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 component names and parameters can be obtained from the first embodiment and are not repeated here.

[0168] Table 7

[0169]

[0170] Table 8

[0171]

[0172]

[0173] The optical system 10 in this embodiment satisfies the following relationship:

[0174] f / TTL 1.032 ct56 / et56 4.83 2*Imgh / TTL 1.111 |sag61| / et6 0.708 f123 / R12 1.42 sag71 / et7 -2.52 f567 / f -2.08 f1 / CT1 15.50 f / f3 1.29

[0175] Depend on Figure 8 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, wherein the meridian field curvature and sagittal field curvature are controlled within 0.025 mm, and the maximum distortion is controlled at about 2.5%, so that the imaging quality of the optical system 10 is excellent.

[0176] Fifth embodiment

[0177] refer to Fig. 9 and Fig.10 In the fifth embodiment, the optical system 10 includes, from the object side to the image side along the optical axis 101, 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 STO, 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 negative refractive power. Fig.10 Included are diagrams of longitudinal spherical aberration, astigmatism, and distortion of the optical system 10 in the fifth embodiment.

[0178] The object-side surface S1 of the first lens L1 is convex near the optical axis, and the image-side surface S2 is concave near the optical axis; the object-side surface S1 is convex near the circumference, and the image-side surface S2 is concave near the circumference.

[0179] The object-side surface S3 of the second lens L2 is convex near the optical axis, and the image-side surface S4 is concave near the optical axis; the object-side surface S3 is convex near the circumference, and the image-side surface S4 is concave near the circumference.

[0180] The object-side surface S5 of the third lens L3 is convex near the optical axis, and the image-side surface S6 is convex near the optical axis; the object-side surface S5 is convex near the circumference, and the image-side surface S6 is concave near the circumference.

[0181] The object-side surface S7 of the fourth lens L4 is concave at the near optical axis, and the image-side surface S8 is concave at the near optical axis; the object-side surface S7 is concave near the circumference, and the image-side surface S8 is concave near the circumference.

[0182] The object-side surface S9 of the fifth lens L5 is concave at the near optical axis, and the image-side surface S10 is convex at the near optical axis; the object-side surface S9 is convex near the circumference, and the image-side surface S10 is concave near the circumference.

[0183] The object-side surface S11 of the sixth lens L6 is concave near the optical axis, and the image-side surface S12 is concave near the optical axis; the object-side surface S11 is concave near the circumference, and the image-side surface S12 is concave near the circumference.

[0184] The object-side surface S13 of the seventh lens L7 is convex near the optical axis, and the image-side surface S14 is concave near the optical axis; the object-side surface S13 is convex near the circumference, and the image-side surface S14 is concave near the circumference.

[0185] 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 component names and parameters can be obtained from the first embodiment and are not repeated here.

[0186] Table 9

[0187]

[0188]

[0189] Table 10

[0190] Surface number S1 S2 S3 S4 S5 S6 S7 K 2.405E-01 3.515E+00 -9.017E-01 -9.586E-01 -1.058E+00 -9.338E+01 -9.900E+01 A4 1.100E-04 -8.960E-03 -7.232E-02 -9.346E-02 3.400E-03 3.145E-02 -2.300E-02 A6 -3.800E-03 1.860E-02 6.002E-02 9.605E-02 5.832E-02 -1.231E-02 1.980E-03 A8 1.760E-03 -8.470E-03 -3.289E-02 -8.242E-02 -7.388E-02 1.538E-02 -4.413E-02 A10 -4.800E-04 1.810E-03 1.200E-02 5.963E-02 7.983E-02 -2.535E-02 1.177E-01 A12 -9.000E-05 -2.200E-04 -1.320E-03 -2.692E-02 -5.459E-02 2.288E-02 -1.576E-01 A14 3.000E-05 2.000E-05 -6.400E-04 7.050E-03 2.304E-02 -1.149E-02 1.252E-01 A16 1.000E-05 0.000E+00 2.500E-04 -1.050E-03 -5.740E-03 3.210E-03 -5.716E-02 A18 0.000E+00 0.000E+00 -3.000E-05 8.000E-05 7.600E-04 -4.600E-04 1.354E-02 A20 0.000E+00 0.000E+00 0.000E+00 0.000E+00 -4.000E-05 3.000E-05 -1.280E-03 Surface number S8 S9 S10 S11 S12 S13 S14 K 6.745E+01 5.482E+01 -9.403E+00 4.950E+01 5.087E+00 9.691E+00 -2.350E+01 A4 -3.781E-02 1.078E-02 4.916E-02 5.527E-02 -1.356E-02 -1.707E-01 -9.181E-02 A6 1.840E-03 -3.668E-02 -9.321E-02 -1.406E-01 -2.738E-02 8.370E-02 3.209E-02 A8 -1.476E-02 3.251E-02 7.767E-02 1.073E-01 -1.460E-03 -4.452E-02 -9.640E-03 A10 5.069E-02 -2.154E-02 -5.223E-02 -8.052E-02 1.129E-02 1.984E-02 1.210E-03 A12 -6.300E-02 1.052E-02 3.156E-02 5.363E-02 -6.220E-03 -7.510E-03 2.900E-04 A14 4.495E-02 -2.300E-03 -1.508E-02 -2.467E-02 1.660E-03 2.020E-03 -1.700E-04 A16 -1.786E-02 -3.000E-05 4.950E-03 6.820E-03 -2.300E-04 -3.200E-04 4.000E-05 A18 3.580E-03 8.000E-05 -9.300E-04 -1.010E-03 2.000E-05 2.000E-05 0.000E+00 A20 -2.800E-04 -1.000E-05 7.000E-05 6.000E-05 0.000E+00 0.000E+00 0.000E+00

[0191] The optical system 10 in this embodiment satisfies the following relationship:

[0192] f / TTL 1.024 ct56 / et56 2.97 2*Imgh / TTL 1.099 |sag61| / et6 0.745 f123 / R12 1.26 sag71 / et7 -2.18 f567 / f -1.77 f1 / CT1 16.74 f / f3 1.45

[0193] 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, wherein the meridian field curvature and sagittal field curvature are controlled within 0.025 mm, and the maximum distortion is controlled at about 2.5%, so that the imaging quality of the optical system 10 is excellent.

[0194] Sixth embodiment

[0195] refer to Fig.11 and Fig.12In the sixth embodiment, the optical system 10 includes, from the object side to the image side along the optical axis 101, 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 STO, 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 negative refractive power. Fig.12 Included are diagrams of longitudinal spherical aberration, astigmatism, and distortion of the optical system 10 in the sixth embodiment.

[0196] The object-side surface S1 of the first lens L1 is convex near the optical axis, and the image-side surface S2 is concave near the optical axis; the object-side surface S1 is convex near the circumference, and the image-side surface S2 is concave near the circumference.

[0197] The object-side surface S3 of the second lens L2 is convex near the optical axis, and the image-side surface S4 is concave near the optical axis; the object-side surface S3 is convex near the circumference, and the image-side surface S4 is convex near the circumference.

[0198] The object-side surface S5 of the third lens L3 is convex near the optical axis, and the image-side surface S6 is convex near the optical axis; the object-side surface S5 is convex near the circumference, and the image-side surface S6 is concave near the circumference.

[0199] The object-side surface S7 of the fourth lens L4 is concave at the near optical axis, and the image-side surface S8 is convex at the near optical axis; the object-side surface S7 is concave near the circumference, and the image-side surface S8 is convex near the circumference.

[0200] The object-side surface S9 of the fifth lens L5 is concave at the near optical axis, and the image-side surface S10 is convex at the near optical axis; the object-side surface S9 is concave near the circumference, and the image-side surface S10 is concave near the circumference.

[0201] The object-side surface S11 of the sixth lens L6 is convex near the optical axis, and the image-side surface S12 is concave near the optical axis; the object-side surface S11 is concave near the circumference, and the image-side surface S12 is concave near the circumference.

[0202] The object-side surface S13 of the seventh lens L7 is convex near the optical axis, and the image-side surface S14 is concave near the optical axis; the object-side surface S13 is convex near the circumference, and the image-side surface S14 is concave near the circumference.

[0203] 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 component names and parameters can be obtained from the first embodiment and are not repeated here.

[0204] Table 11

[0205]

[0206] Table 12

[0207]

[0208]

[0209] The optical system 10 in this embodiment satisfies the following relationship:

[0210] f / TTL 1.015 ct56 / et56 5.14 2*Imgh / TTL 1.105 |sag61| / et6 0.752 f123 / R12 1.07 sag71 / et7 -1.16 f567 / f -1.12 f1 / CT1 23.03 f / f3 1.36

[0211] 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, wherein the meridian field curvature and sagittal field curvature are controlled within 0.025 mm, and the maximum distortion is controlled at about 2.5%, so that the imaging quality of the optical system 10 is excellent.

[0212] Seventh embodiment

[0213] refer to Fig.13 and Fig.14 In the seventh embodiment, the optical system 10 includes, from the object side to the image side along the optical axis 101, 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 STO, 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 negative refractive power. Fig.14 Included are diagrams of longitudinal spherical aberration, astigmatism, and distortion of the optical system 10 in the seventh embodiment.

[0214] The object-side surface S1 of the first lens L1 is convex near the optical axis, and the image-side surface S2 is concave near the optical axis; the object-side surface S1 is convex near the circumference, and the image-side surface S2 is concave near the circumference.

[0215] The object-side surface S3 of the second lens L2 is convex near the optical axis, and the image-side surface S4 is concave near the optical axis; the object-side surface S3 is convex near the circumference, and the image-side surface S4 is convex near the circumference.

[0216] The object-side surface S5 of the third lens L3 is convex near the optical axis, and the image-side surface S6 is convex near the optical axis; the object-side surface S5 is convex near the circumference, and the image-side surface S6 is concave near the circumference.

[0217] The object-side surface S7 of the fourth lens L4 is concave at the near optical axis, and the image-side surface S8 is convex at the near optical axis; the object-side surface S7 is concave near the circumference, and the image-side surface S8 is convex near the circumference.

[0218] The object-side surface S9 of the fifth lens L5 is concave at the near optical axis, and the image-side surface S10 is convex at the near optical axis; the object-side surface S9 is concave near the circumference, and the image-side surface S10 is concave near the circumference.

[0219] The object-side surface S11 of the sixth lens L6 is convex near the optical axis, and the image-side surface S12 is concave near the optical axis; the object-side surface S11 is concave near the circumference, and the image-side surface S12 is concave near the circumference.

[0220] The object-side surface S13 of the seventh lens L7 is convex near the optical axis, and the image-side surface S14 is concave near the optical axis; the object-side surface S13 is convex near the circumference, and the image-side surface S14 is concave near the circumference.

[0221] In addition, the lens parameters of the optical system 10 in the seventh embodiment are given in Table 13 and Table 14, wherein the definitions of the component names and parameters can be obtained from the first embodiment and are not repeated here.

[0222] Table 13

[0223]

[0224]

[0225] Table 14

[0226] Surface number S1 S2 S3 S4 S5 S6 S7 K 1.997E-01 3.463E+00 -1.499E+00 -9.003E-01 -4.002E+00 5.801E+01 3.436E+01 A4 -1.900E-04 -3.066E-02 -8.195E-02 -7.565E-02 1.365E-02 -9.600E-04 -3.398E-02 A6 -4.230E-03 2.421E-02 4.031E-02 2.860E-02 5.830E-03 6.500E-03 1.800E-02 A8 3.420E-03 -6.010E-03 4.570E-03 6.160E-03 -1.217E-02 -8.500E-03 -1.457E-02 A10 -1.860E-03 4.500E-04 -1.173E-02 7.400E-04 2.776E-02 4.670E-03 5.160E-03 A12 6.300E-04 5.000E-05 5.810E-03 -3.730E-03 -2.030E-02 -3.800E-04 7.210E-03 A14 -1.500E-04 -1.000E-05 -1.660E-03 1.390E-03 7.250E-03 -5.600E-04 -1.081E-02 A16 3.000E-05 0.000E+00 2.900E-04 -2.100E-04 -1.300E-03 2.200E-04 6.010E-03 A18 0.000E+00 0.000E+00 -3.000E-05 1.000E-05 9.000E-05 -3.000E-05 -1.570E-03 A20 0.000E+00 0.000E+00 0.000E+00 0.000E+00 0.000E+00 0.000E+00 1.600E-04 Surface number S8 S9 S10 S11 S12 S13 S14 K -9.900E+01 1.553E+01 -9.708E+00 -7.459E+00 5.582E+00 8.364E+00 -1.993E+01 A4 -4.643E-02 -1.933E-02 -2.061E-02 -8.126E-02 -1.024E-01 -1.319E-01 -5.958E-02 A6 1.672E-02 1.147E-02 2.045E-02 9.139E-02 9.686E-02 5.522E-02 1.436E-02 A8 -1.357E-02 -3.729E-02 -6.502E-02 -1.722E-01 -1.160E-01 -2.328E-02 -1.530E-03 A10 4.950E-03 6.582E-02 9.402E-02 1.636E-01 8.471E-02 8.830E-03 -9.800E-04 A12 5.920E-03 -6.712E-02 -8.085E-02 -9.847E-02 -4.007E-02 -3.110E-03 5.700E-04 A14 -8.720E-03 4.409E-02 4.560E-02 3.724E-02 1.227E-02 7.800E-04 -1.500E-04 A16 4.510E-03 -1.719E-02 -1.578E-02 -8.290E-03 -2.310E-03 -1.100E-04 2.000E-05 A18 -1.040E-03 3.480E-03 2.980E-03 9.800E-04 2.400E-04 1.000E-05 0.000E+00 A20 9.000E-05 -2.800E-04 -2.300E-04 -5.000E-05 -1.000E-05 0.000E+00 0.000E+00

[0227] The optical system 10 in this embodiment satisfies the following relationship:

[0228] f / TTL 1.005 ct56 / et56 3.45 2*Imgh / TTL 1.097 |sag61| / et6 0.947 f123 / R12 1.14 sag71 / et7 -1.21 f567 / f -1.04 f1 / CT1 18.68 f / f3 1.38

[0229] Depend on Fig.14 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, wherein the meridian field curvature and sagittal field curvature are controlled within 0.025 mm, and the maximum distortion is controlled at about 5%, so that the imaging quality of the optical system 10 is excellent.

[0230] Eighth embodiment

[0231] refer to Fig.15 and Fig.16 In the eighth embodiment, the optical system 10 includes, from the object side to the image side along the optical axis 101, 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 STO, 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 negative refractive power. Fig.16 Included are diagrams of longitudinal spherical aberration, astigmatism, and distortion of the optical system 10 in the eighth embodiment.

[0232] The object-side surface S1 of the first lens L1 is convex near the optical axis, and the image-side surface S2 is concave near the optical axis; the object-side surface S1 is convex near the circumference, and the image-side surface S2 is concave near the circumference.

[0233] The object-side surface S3 of the second lens L2 is convex near the optical axis, and the image-side surface S4 is concave near the optical axis; the object-side surface S3 is convex near the circumference, and the image-side surface S4 is concave near the circumference.

[0234] The object-side surface S5 of the third lens L3 is convex near the optical axis, and the image-side surface S6 is convex near the optical axis; the object-side surface S5 is convex near the circumference, and the image-side surface S6 is concave near the circumference.

[0235] The object-side surface S7 of the fourth lens L4 is concave at the near optical axis, and the image-side surface S8 is concave at the near optical axis; the object-side surface S7 is concave near the circumference, and the image-side surface S8 is convex near the circumference.

[0236] The object-side surface S9 of the fifth lens L5 is concave at the near optical axis, and the image-side surface S10 is convex at the near optical axis; the object-side surface S9 is concave near the circumference, and the image-side surface S10 is concave near the circumference.

[0237] The object-side surface S11 of the sixth lens L6 is concave near the optical axis, and the image-side surface S12 is concave near the optical axis; the object-side surface S11 is concave near the circumference, and the image-side surface S12 is convex near the circumference.

[0238] The object-side surface S13 of the seventh lens L7 is convex near the optical axis, and the image-side surface S14 is concave near the optical axis; the object-side surface S13 is convex near the circumference, and the image-side surface S14 is concave near the circumference.

[0239] In addition, the lens parameters of the optical system 10 in the eighth embodiment are given in Table 15 and Table 16, wherein the definitions of the component names and parameters can be obtained from the first embodiment and are not repeated here.

[0240] Table 15

[0241]

[0242] Table 16

[0243]

[0244]

[0245] The optical system 10 in this embodiment satisfies the following relationship:

[0246] f / TTL 1.092 ct56 / et56 6.60 2*Imgh / TTL 1.167 |sag61| / et6 1.003 f123 / R12 1.59 sag71 / et7 -1.57 f567 / f -0.93 f1 / CT1 16.43 f / f3 1.59

[0247] Depend on Fig.16 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, wherein the meridian field curvature and sagittal field curvature are controlled within 0.05 mm, and the maximum distortion is controlled within 2.5%, so that the imaging quality of the optical system 10 is excellent.

[0248] The optical system 10 in the first to eighth embodiments mentioned above, through the reasonable combination design of the refractive power, surface structure and parameter relationship of the seven lenses, can not only compress the system length, but also have a telephoto characteristic, and can also match an image sensor with a larger photosensitive surface. Therefore, the optical system 10 can achieve better processing of distant details on the basis of satisfying the miniaturized design, thereby achieving the imaging effect of compressing the shooting distance.

[0249] refer to Fig.17 Some embodiments of the present application further provide a camera module 20, which may include an optical system 10 and an image sensor 210, wherein the image sensor 210 is disposed on the image side of the optical system 10. The image sensor 210 may be a CCD sensor (Charge Coupled Device) or a CMOS sensor (Complementary Metal Oxide Semiconductor). Generally, during assembly, the imaging surface S15 of the optical system 10 overlaps with the photosensitive surface of the image sensor 210.

[0250] By adopting the optical system 10 in any of the above-mentioned embodiments, the camera module 20 will have a telephoto characteristic, so that it can better process distant details and thus have excellent telephoto performance; at the same time, the length of the camera module 20 can also be compressed to achieve a miniaturized design, thereby reducing the space occupied in the thickness direction of the device, which is conducive to the ultra-thin design of the device.

[0251] refer to Fig.18, some embodiments of the present application also provide an electronic device 30. The electronic device 30 includes a fixing part 310, and the camera module 20 is installed on the fixing part 310. The fixing part 310 can be a display screen, a circuit board, a middle frame, a back cover and other components. The electronic device 30 includes but is not limited to smart phones, smart watches, smart glasses, e-book readers, vehicle-mounted camera equipment, monitoring equipment, drones, medical equipment (such as endoscopes), tablet computers, biometric devices (such as fingerprint recognition devices or pupil recognition devices, etc.), PDAs (Personal Digital Assistants), drones, etc. By adopting the above-mentioned camera module 20, the electronic device 30 can assemble the camera module 20 in a smaller space, and at the same time, the camera module 20 can be used to obtain a good long-range shooting effect.

[0252] 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.

[0253] 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, which include the following from the object side to the image side along the optical axis: A first lens having positive refractive power, wherein the object side surface of the first lens is convex at the near optical axis, and the image side surface of the first lens is concave at the near optical axis; a second lens having negative refractive power, wherein the object side surface of the second lens is convex at the near optical axis, and the image side surface of the second lens is concave at the near optical axis; a third lens having positive refractive power, wherein the object side surface of the third lens is convex at a position close to the optical axis; a fourth lens having a refractive power; a fifth lens element having a refractive power, wherein the image side surface of the fifth lens element is a convex surface near the optical axis; a sixth lens having refractive power, wherein the image side surface of the sixth lens is a concave surface near the optical axis, and the object side surface and the image side surface of the sixth lens are both aspherical surfaces; a seventh lens having a refractive power, wherein the object side surface of the seventh lens is a convex surface near the optical axis, the image side surface is a concave surface near the optical axis, the object side surface and the image side surface are both aspherical surfaces, and at least one of the object side surface and the image side surface has an inflection point; The optical system also satisfies the relationship: 1.004<f / TTL<1.1, 1.09<2 Imgh / TTL<1.2; and f is the effective focal length of the optical system, 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 Imgh is half of the image height corresponding to the maximum field of view of the optical system.

2. The optical system according to claim 1, characterized in that The optical system satisfies the relationship: 1<f123 / R12<1.8; f123 is the combined focal length of the first lens, the second lens and the third lens, and R12 is the radius of curvature of the image side surface of the first lens at the optical axis.

3. The optical system according to claim 1, characterized in that The optical system satisfies the relationship: -2.2<f567 / f<-0.9; f567 is the combined focal length of the fifth lens, the sixth lens and the seventh lens.

4. The optical system according to claim 1, characterized in that The optical system satisfies the relationship: 1<f / f3<1.6; f3 is the effective focal length of the third lens.

5. The optical system according to claim 1, characterized in that The optical system satisfies the relationship: 2.5<ct56 / et56<7; ct56 is the distance from the image side surface of the fifth lens to the object side surface of the sixth lens on the optical axis, and et56 is the distance from the maximum effective aperture of the image side surface of the fifth lens to the maximum effective aperture of the object side surface of the sixth lens in the direction of the optical axis.

6. The optical system according to claim 1, characterized in that The optical system satisfies the relationship: 0.4<|sag61| / et6<1.1; sag61 is the sag height of the object side surface of the sixth lens at the maximum effective aperture, and et6 is the thickness of the sixth lens from the maximum effective aperture of the object side surface to the maximum effective aperture of the image side surface in the optical axis direction.

7. The optical system according to claim 1, characterized in that The optical system satisfies the relationship: -3<sag71 / et7<-1; sag71 is the sag height of the object side surface of the seventh lens at the maximum effective aperture, and et7 is the thickness of the seventh lens from the maximum effective aperture of the object side surface to the maximum effective aperture of the image side surface in the optical axis direction.

8. The optical system according to claim 1, characterized in that The optical system satisfies the relationship: 14<f1 / CT1<23.5; f1 is the effective focal length of the first lens, and CT1 is the thickness of the first lens on the optical axis.

9. A camera module, characterized in that: The optical system comprises an image sensor and the optical system according to any one of claims 1 to 8, wherein the image sensor is arranged on the image side of the optical system.

10. An electronic device, characterized in that: It comprises a fixing part and the camera module as claimed in claim 9, wherein the camera module is arranged on the fixing part.

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