Optical system, camera module and electronic device

Abstract

An optical system, a camera module and an electronic device, the optical system comprising, in order from an object side to an image side along an optical axis, a first lens to an eighth lens having refractive power, and the first lens, the second lens, the fifth lens and the seventh lens having negative refractive power, and the third lens, the fourth lens, the sixth lens and the eighth lens having positive refractive power, wherein the image side surface of the first lens, the object side surface of the second lens, the object side surface of the fifth lens, the object side surface of the seventh lens and the image side surface of the eighth lens are all concave at a vicinity of the optical axis, and the object side surface of the first lens, the image side surface of the second lens, the object side surface of the third lens, the object side surface and the image side surface of the fourth lens, the image side surface of the fifth lens, the object side surface and the image side surface of the sixth lens and the object side surface of the eighth lens are all convex at a vicinity of the optical axis. By reasonably designing the surface shape and the refractive power of each lens of the optical system, it is conducive to meeting the characteristics of large field of view and miniaturization.

Description

Technical Field

[0001] This invention belongs to the field of optical imaging technology, and particularly relates to an optical system, a camera module, and an electronic device. Background Technology

[0002] With the rapid development of automotive driver assistance technology, optical systems are widely used in automobiles, especially in areas such as in-vehicle reversing camera systems, dashcams, automatic parking systems, panoramic imaging systems, and road navigation, where optical systems have become an indispensable key component.

[0003] Vehicle-mounted cameras are crucial components for acquiring external information in autonomous driving assistance systems. For safety reasons, the performance requirements for these cameras are extremely stringent. Firstly, they must have high image clarity to effectively distinguish details of the road environment. Secondly, they need a wide field of view to better capture road information ahead of the vehicle, meeting the specific requirements of intelligent driving systems. Furthermore, due to the limited installation space in vehicles, the size of the cameras used cannot be too large. Summary of the Invention

[0004] The purpose of this invention is to provide an optical system, camera module, and electronic device that solves the problem of the need for a large field of view and miniaturization in automotive optical systems.

[0005] To achieve the objectives of this invention, the following technical solution is provided:

[0006] In a first aspect, the present invention provides an optical system comprising eight lenses with refractive power, arranged sequentially along the optical axis from the object side to the image side: a first lens having negative refractive power, wherein the object side of the first lens is convex near the optical axis and the image side of the first lens is concave near the optical axis; a second lens having negative refractive power, wherein the object side of the second lens is concave near the optical axis and the image side of the second lens is convex near the optical axis; a third lens having positive refractive power, wherein the object side of the third lens is convex near the optical axis; and a fourth lens having positive refractive power, wherein the object side of the fourth lens is convex near the optical axis. The fourth lens has a convex image-side surface near the optical axis; the fifth lens has negative refractive power, with its object-side surface near the optical axis being concave and its image-side surface near the optical axis being convex; the sixth lens has positive refractive power, with its object-side surface near the optical axis being convex and its image-side surface near the optical axis being convex; the seventh lens has negative refractive power, with its object-side surface near the optical axis being concave; and the eighth lens has positive refractive power, with its object-side surface near the optical axis being convex and its image-side surface near the optical axis being concave.

[0007] The optical system satisfies the following relationships: 125deg≤FOV≤139deg, 8.5≤TTL / F≤9.1, 1.45≤SD1 / IMGH≤1.82; where FOV is the maximum field of view of the optical system, TTL is the distance on the optical axis from the object side of the first lens to the imaging plane, F is the effective focal length of the optical system, SD1 is half of the maximum effective aperture of the object side of the first lens, and IMGH is half of the image height corresponding to the maximum field of view of the optical system.

[0008] By making the first lens have negative refractive power, and its object-side surface is convex near the optical axis while its image-side surface is concave near the optical axis, it is beneficial to collect large-field-of-view light rays into the rear lens, increasing the light transmission of the optical system and fixing the direction of large-angle light rays at the edges; by making the second lens have negative refractive power, and its object-side surface is concave near the optical axis while its image-side surface is convex near the optical axis, it is beneficial to further diverge light rays, adjust the refractive angle of the light rays, and reduce the chromatic aberration of the optical system; The third lens is made to have positive refractive power, and its object-side surface is convex near the optical axis. This facilitates light convergence, allowing the light to smoothly enter the rear lens and reducing the sensitivity of the optical system. The fourth lens is also made to have positive refractive power, and both its object-side and image-side surfaces are convex near the optical axis. This helps to compress the angle of the incident light, achieving a smooth transition and allowing diverging light to smoothly enter the rear lens, further smoothing the light path and reducing the aperture of the rear lens. The fifth lens has negative refractive power, and its object-side surface is concave near the optical axis, while its image-side surface is convex near the optical axis. This facilitates the entry and deflection of peripheral light rays, reducing the deflection angle borne by subsequent lenses and resulting in a more uniform deflection angle across all lenses, effectively correcting aberrations in the peripheral field of view. By making the sixth lens positive refractive power, and with both its object-side and image-side surfaces convex near the optical axis, aberrations are further reduced, image quality is improved, and distortion is optimized. The light rays converge effectively and smoothly. By making the seventh lens have negative refractive power and its object-side surface is concave near the optical axis, it is beneficial to make the light rays move smoothly, which facilitates the correction of astigmatism and distortion and can improve the imaging quality of the optical system. By making the eighth lens have positive refractive power and its object-side surface is convex near the optical axis and its image-side surface is concave near the optical axis, it is beneficial to make as many large-angle light rays as possible smoothly transition to the rear optical elements, which can correct astigmatism and field curvature and improve the resolving power of the optical system.

[0009] By ensuring that the optical system satisfies the relationship 125deg≤FOV≤139deg, the optical system has a large field of view, thereby enabling wide-angle imaging and facilitating the optical system to obtain a sufficient field of view.

[0010] By ensuring that the optical system satisfies the relationship 8.5≤TTL / F≤9.1, the ratio of the total length of the optical system to its focal length is controlled within a reasonable range, thereby achieving miniaturization of the optical system. This facilitates better convergence of light onto the imaging surface and improves the imaging quality of the optical system.

[0011] By ensuring that the optical system satisfies the relationship 1.45≤SD1 / IMGH≤1.82, the ratio of half the maximum effective aperture of the object side of the first lens to half the image height corresponding to the maximum field of view of the optical system can be reasonably configured. This is beneficial for reasonably controlling the size of the object side of the first lens and realizing the miniaturization of the optical system.

[0012] In one embodiment, the optical system satisfies the relationship: 7.5 ≤ TTL / IMGH ≤ 8.3; where IMGH is half the image height corresponding to the maximum field of view of the optical system. By making the optical system satisfy the above relationship, under a certain image height of the optical system, the miniaturization requirement of the optical system can be achieved while ensuring imaging quality by controlling the ratio of image height to focal length.

[0013] In one embodiment, the optical system satisfies the relationship: 0.85 ≤ F / IMGH ≤ 0.95. By making the optical system satisfy the above relationship, the refractive power of the optical system for light is matched with the image plane size, thereby improving the imaging quality of the optical system.

[0014] In one embodiment, the optical system satisfies the relationship: 76deg≤FOV / FNO≤87deg; where FNO is the aperture number of the optical system. By ensuring that the optical system satisfies the above relationship, the ratio of the field of view to the aperture number of the optical system can be reasonably configured, achieving a combination effect of a large field of view and a large aperture. The optical system has a reasonable amount of light intake, improving the overall illuminance of the image and making the optical system suitable for different lighting environments.

[0015] In one embodiment, the optical system satisfies the relationship: 2.5 ≤ F3 / F ≤ 3; where F3 is the effective focal length of the third lens. By ensuring the optical system satisfies the above relationship and appropriately setting the effective focal length of the third lens, incident light rays can be effectively collected and compressed, allowing light to smoothly transition into the rear optical system, reducing aberrations, and thus improving the image quality of the lens.

[0016] In one embodiment, the optical system satisfies the relationship: 1.6 ≤ F4 / F ≤ 2.1; where F4 is the effective focal length of the fourth lens. By ensuring that the optical system satisfies the above relationship, it is beneficial to properly match the refractive power of the fourth lens within the optical system, making the surface design of the fourth lens simpler and more flexible, reducing aberrations, and simplifying the overall aberration correction and image quality balance of the optical system.

[0017] In one embodiment, the optical system satisfies the relationship: -4.5 ≤ F5 / F ≤ -2.7; where F5 is the effective focal length of the fifth lens. By ensuring that the optical system satisfies the above relationship, the refractive power of the fifth lens in the optical system is properly matched, the surface design of the fifth lens is simpler and more flexible, aberrations are reduced, and the overall aberration correction and image quality balance of the optical system are simplified.

[0018] In one embodiment, the optical system satisfies the relationship: 1.1 ≤ BFL / F ≤ 1.5; where BFL is the distance on the optical axis from the image-side surface of the seventh lens to the imaging surface of the optical system. By ensuring that the optical system satisfies the above relationship, it is beneficial to achieve a balance between obtaining good image quality and an easy-to-assemble optical back focal length, thus ensuring the image quality of the optical system while reducing the design and assembly difficulty of the optical system and improving the yield rate.

[0019] In one embodiment, the optical system satisfies the relationship: 4.2 ≤ CT4 / CT34 ≤ 15; where CT4 is the thickness of the fourth lens on the optical axis, and CT34 is the distance on the optical axis from the image side of the third lens to the object side of the fourth lens. By making the optical system satisfy the above relationship, the thickness of the fourth lens on the optical axis is reasonably set, and at the same time, the distance between the third and fourth lenses on the optical axis is also reasonably set, which is beneficial for controlling the incident angle of light and maintaining the miniaturization of the optical system.

[0020] In one embodiment, the optical system satisfies the relationship: -2.8 ≤ R7 / R8 ≤ -1.5; where R7 is the radius of curvature of the object-side surface of the fourth lens at the optical axis, and R8 is the radius of curvature of the image-side surface of the fourth lens at the optical axis. By ensuring that the optical system satisfies the above relationship, it is beneficial to rationally configure the ratio of the radius of curvature of the object-side surface of the fourth lens at the optical axis to that of the image-side surface of the fourth lens at the optical axis, control the shape of the fourth lens, comprehensively balance the spherical aberration, chromatic aberration, and field curvature of the optical system, reduce the risk of ghosting, improve the resolving power of the optical system, and at the same time, reduce the manufacturing difficulty of the fourth lens.

[0021] In one embodiment, the optical system satisfies the relationship: 0.58 ≤ R15 / R16 ≤ 0.85; where R15 is the radius of curvature of the object-side surface of the eighth lens at the optical axis, and R16 is the radius of curvature of the image-side surface of the eighth lens at the optical axis. By ensuring that the optical system satisfies the above relationship, it is beneficial to rationally configure the ratio of the radius of curvature of the object-side surface of the eighth lens at the optical axis to that of the image-side surface of the eighth lens at the optical axis, control the shape of the eighth lens, comprehensively balance the spherical aberration, chromatic aberration, and field curvature of the optical system, reduce the risk of ghosting, improve the resolving power of the optical system, and at the same time, it also helps to reduce the processing difficulty of the fourth lens.

[0022] In one embodiment, the optical system satisfies the relationship: 2.1 ≤ CT4 / CT5 ≤ 5.4; where CT5 is the thickness of the fifth lens along the optical axis. By making the optical system satisfy the above relationship, the ratio of the thickness of the fourth lens along the optical axis to the thickness of the fifth lens along the optical axis can be reasonably configured, and the fourth and fifth lenses can be mutually adjusted to maintain the miniaturized characteristics of the optical system.

[0023] In one embodiment, the optical system satisfies the relationship: 3.7 ≤ Vd4 / Vd5 ≤ 3.9; where Vd4 is the Abbe number of the fourth lens and Vd5 is the Abbe number of the fifth lens. By ensuring that the optical system satisfies the above relationship, the ratio of the Abbe number of the fourth lens to the Abbe number of the fifth lens is within a reasonable range, which can effectively correct the axial chromatic aberration of the optical system.

[0024] In one embodiment, the optical system satisfies the following relationship: -0.7mm ≤ F6 / Vd6 + F7 / Vd7 ≤ -0.2mm; where F6 is the effective focal length of the sixth lens, Vd6 is the Abbe number of the sixth lens, F7 is the effective focal length of the seventh lens, and Vd7 is the Abbe number of the seventh lens. By ensuring that the optical system satisfies the above relationship, chromatic dispersion of the optical system can be effectively counteracted, which is beneficial for achieving confocal focusing of visible and infrared light in both bands.

[0025] In one embodiment, the optical system satisfies the relationship: 0.17≤SD1 / TTL≤0.25. By making the optical system satisfy the above relationship, the ratio of the optical aperture value of the first lens to the total length of the optical system can be reasonably configured, which helps to limit the volume of the optical system and realize the miniaturization of the optical system.

[0026] In one embodiment, the optical system satisfies the relationship: 1 ≤ SD11 / SD10 ≤ 1.1; where SD11 is half the maximum effective aperture of the object side of the sixth lens, and SD10 is half the maximum effective aperture of the image side of the fifth lens. By making the optical system satisfy the above relationship, the transition between the fifth and sixth lenses is smooth, reducing the step difference between them, which in turn facilitates the smooth entry of light into the sixth lens and improves the illumination of the optical system.

[0027] In one embodiment, the optical system satisfies the relationship: -8.5 ≤ F123 / F ≤ -3; where F123 is the combined effective focal length of the first lens, the second lens, and the third lens. By ensuring that the optical system satisfies the above relationship, the ratio of the combined effective focal length of the first lens, the second lens, and the third lens to the effective focal length of the optical system can be reasonably configured. This, along with a reasonable matching of the front lens combination focal length of the aperture stop, facilitates better distortion correction and achieves low distortion in the optical system.

[0028] In one embodiment, the optical system satisfies the relationship: 3.4 ≤ F45 / F ≤ 4.7; where F45 is the combined effective focal length of the fourth and fifth lenses. By ensuring the optical system satisfies this relationship, the ratio of the effective focal length of the cemented lens (combined with the fourth and fifth lenses) to the effective focal length of the optical system is rationally configured. This facilitates the correction of chromatic aberration and balances various aberrations, improving the resolving power of the optical system, effectively reducing the tolerance sensitivity of the optical system, and ultimately enhancing the imaging quality of the optical system.

[0029] In one embodiment, the optical system satisfies the relationship: 5.5 ≤ F67 / F ≤ 11; where F67 is the combined effective focal length of the sixth and seventh lenses. By ensuring the optical system satisfies this relationship, the ratio of the effective focal length of the cemented lens (combined with the sixth and seventh lenses) to the effective focal length of the optical system is rationally configured. This allows light to smoothly transition into the rear optical system, which helps balance various aberrations, improves lens resolution, and simultaneously reduces tolerance sensitivity, thereby increasing the production yield of the optical system.

[0030] In one embodiment, the optical system satisfies the relationship: 1.6 ≤ FNO ≤ 1.7; where FNO is the aperture number of the optical system. By ensuring that the optical system satisfies the above relationship, the aperture number of the optical system is set within a reasonable range, achieving a combination of a large field of view and a large aperture. The optical system has a reasonable amount of light intake, improving the overall illuminance of the image and making the optical system suitable for different lighting environments.

[0031] In one embodiment, the optical system satisfies the relationship: 1.7 ≤ F × tan(FOV / 2) / IMGH ≤ 2.3. By ensuring that the optical system satisfies the above relationship, it is helpful to better control the optical distortion of the optical system and improve the resolving power of the optical system.

[0032] In one embodiment, the optical system satisfies the relationship: 2.8 ≤ ∑CT / ∑AT ≤ 4.4; where ∑CT is the sum of the thicknesses of the first to eighth lenses along the optical axis, and ∑AT is the sum of the distances between adjacent lenses along the optical axis. By ensuring the optical system satisfies the above relationship, the ratio of the sum of the thicknesses of the first to eighth lenses along the optical axis to the sum of the distances between adjacent lenses along the optical axis can be rationally configured. This allows for the rational setting of the thickness of each lens and the distance between adjacent lenses in the optical system, achieving miniaturization of the optical system, improving its manufacturability, and facilitating mutual adjustment of the thicknesses of each lens and the distance between adjacent lenses. This reduces aberrations and tolerance sensitivity of the optical system, thereby improving its imaging quality.

[0033] Secondly, the present invention also provides a camera module, which includes a photosensitive chip and an optical system as described in any embodiment of the first aspect, wherein the photosensitive chip is disposed on the image side of the optical system. The photosensitive surface of the photosensitive chip is located on the imaging surface of the optical system, and light rays from an object incident on the photosensitive surface through a lens can be converted into electrical signals for an image. The photosensitive chip can be a complementary metal-oxide-semiconductor (CMOS) or a charge-coupled device (CCD). The camera module can be an imaging module integrated into an electronic device or a standalone lens. By incorporating the optical system provided by the present invention into the camera module, the camera module can achieve a large field of view and miniaturization through reasonable design of the surface shape and refractive power of each lens in the optical system.

[0034] Thirdly, the present invention also provides an electronic device comprising a housing and the camera module described in the second aspect, wherein the camera module is disposed within the housing. This electronic device includes, but is not limited to, automobiles, surveillance equipment, smartphones, computers, and smartwatches. By incorporating the camera module provided by the present invention into the electronic device, the electronic device achieves a wide field of view and miniaturization. Attached Figure Description

[0035] To more clearly illustrate the technical solutions in the embodiments of the present invention or the prior art, the drawings used in the description of the embodiments or the prior art will be briefly introduced below. Obviously, the drawings described below are only some embodiments of the present invention. For those skilled in the art, other drawings can be obtained from these drawings without creative effort.

[0036] Figure 1 This is a schematic diagram of the optical system of the first embodiment;

[0037] Figure 2 The diagrams showing the longitudinal spherical aberration, astigmatism, and distortion curves of the optical system of the first embodiment are illustrated.

[0038] Figure 3 This is a schematic diagram of the optical system of the second embodiment;

[0039] Figure 4 The longitudinal spherical aberration curve, astigmatism curve, and distortion curve of the optical system of the second embodiment are shown.

[0040] Figure 5 This is a schematic diagram of the optical system of the third embodiment;

[0041] Figure 6 The longitudinal spherical aberration curve, astigmatism curve, and distortion curve of the optical system of the third embodiment are shown.

[0042] Figure 7 This is a schematic diagram of the optical system of the fourth embodiment;

[0043] Figure 8 The longitudinal spherical aberration curve, astigmatism curve, and distortion curve of the optical system of the fourth embodiment are shown.

[0044] Figure 9 This is a schematic diagram of the optical system of the fifth embodiment;

[0045] Figure 10 The longitudinal spherical aberration curve, astigmatism curve, and distortion curve of the optical system of the fifth embodiment are shown.

[0046] Figure 11 This is a schematic diagram of the optical system in the sixth embodiment;

[0047] Figure 12 The longitudinal spherical aberration curve, astigmatism curve, and distortion curve of the optical system of the sixth embodiment are shown.

[0048] Figure 13 A schematic diagram of the camera module structure in one embodiment of the present invention is shown;

[0049] Figure 14 A schematic diagram of the structure of an electronic device according to one embodiment of the present invention is shown. Detailed Implementation

[0050] The technical solutions of the embodiments of the present invention will be clearly and completely described below with reference to the accompanying drawings. Obviously, the described embodiments are only a part of the embodiments of the present invention, and not all of them. Based on the embodiments of the present invention, all other embodiments obtained by those skilled in the art without creative effort are within the scope of protection of the present invention.

[0051] This invention provides an optical system comprising eight refractive lenses, arranged sequentially along the optical axis from the object side to the image side: a first lens with negative refractive power, wherein the object side of the first lens is convex near the optical axis and the image side of the first lens is concave near the optical axis; a second lens with negative refractive power, wherein the object side of the second lens is concave near the optical axis and the image side of the second lens is convex near the optical axis; a third lens with positive refractive power, wherein the object side of the third lens is convex near the optical axis; and a fourth lens with positive refractive power, wherein the object side of the fourth lens is convex near the optical axis. The fourth lens has a convex image-side surface near the optical axis; the fifth lens has negative refractive power, with its object-side surface near the optical axis being concave and its image-side surface near the optical axis being convex; the sixth lens has positive refractive power, with its object-side surface near the optical axis being convex and its image-side surface near the optical axis being convex; the seventh lens has negative refractive power, with its object-side surface near the optical axis being concave; and the eighth lens has positive refractive power, with its object-side surface near the optical axis being convex and its image-side surface near the optical axis being concave.

[0052] The optical system satisfies the following relationships: 125deg≤FOV≤139deg, 8.5≤TTL / F≤9.1, 1.45≤SD1 / IMGH≤1.82; where FOV is the maximum field of view of the optical system, TTL is the distance on the optical axis from the object-side surface of the first lens to the imaging plane, F is the effective focal length of the optical system, SD1 is half of the maximum effective aperture of the object-side surface of the first lens, and IMGH is half of the image height corresponding to the maximum field of view of the optical system. Specifically, the value of FOV can be 126deg, 128deg, 130deg, 132deg, 134deg, 136deg, 138deg, 139deg, etc. Specifically, the value of TTL / F can be 8.553, 8.612, 8.702, 8.769, 8.786, 8.805, 8.941, 8.996, 9.020, 9.095, etc. Specifically, the values ​​of SD1 / IMGH can be 1.483, 1.486, 1.525, 1.566, 1.577, 1.625, 1.653, 1.694, 1.759, 1.804, etc.

[0053] By making the first lens have negative refractive power, and its object-side surface is convex near the optical axis while its image-side surface is concave near the optical axis, it is beneficial to collect large-field-of-view light rays into the rear lens, increasing the light transmission of the optical system and fixing the direction of large-angle light rays at the edges. By making the second lens have negative refractive power, and its object-side surface is concave near the optical axis while its image-side surface is convex near the optical axis, it is beneficial to further diverge light rays, adjust the refraction angle of light rays, and reduce chromatic aberration in the optical system. By making the third lens have positive refractive power and its object-side surface is convex near the optical axis, it is beneficial to further diverge light rays, adjust the refraction angle of light rays, and reduce chromatic aberration in the optical system. This design facilitates the convergence of light rays, allowing them to enter the rear lens smoothly and reducing the sensitivity of the optical system. By giving the fourth lens positive refractive power, and ensuring both its object-side and image-side surfaces are convex near the optical axis, the angle of the incident light rays is compressed, resulting in a smooth transition and allowing diverging light rays to enter the rear lens smoothly. This further smooths the light path and reduces the aperture of the rear lens. Furthermore, by giving the fifth lens negative refractive power, and ensuring both its object-side and image-side surfaces are concave near the optical axis, the design facilitates the entry and deflection of peripheral light rays, further reducing the sensitivity of the optical system. The smaller rear lens bears the deflection angle, making the deflection angle of light more uniform across all lenses, effectively correcting aberrations at the edges of the field of view; the fourth and fifth lenses are cemented lenses, which helps correct chromatic aberration and balance various aberrations, improving the resolving power of the optical system and effectively reducing tolerance sensitivity, thus enhancing the imaging quality of the optical system; by giving the sixth lens positive refractive power, and by making both the object-side and image-side surfaces of the sixth lens convex near the optical axis, it is beneficial to further reduce aberrations, improve imaging quality, optimize distortion, and ensure effective and stable convergence of light; by giving the seventh lens negative refractive power... The seventh lens has a positive refractive power, and its object-side surface is concave near the optical axis, which facilitates smooth light path, reduces astigmatism and distortion, and improves the imaging quality of the optical system. The sixth and seventh lenses are cemented lenses, which helps reduce chromatic aberration, improves image quality, and reduces field curvature, thereby correcting off-axis point aberrations. By making the eighth lens positively refractive, and its object-side surface is convex near the optical axis while its image-side surface is concave near the optical axis, it helps to smoothly transition as many large-angle peripheral rays as possible to the rear optical elements, which can correct astigmatism and field curvature and improve the resolving power of the optical system.

[0054] By ensuring that the optical system satisfies the relationship 125deg≤FOV≤139deg, the optical system has a large field of view, thereby enabling wide-angle imaging and facilitating the optical system to obtain a sufficient field of view.

[0055] By ensuring that the optical system satisfies the relationship 8.5≤TTL / F≤9.1, the ratio of the total length of the optical system to its focal length is controlled within a reasonable range, thereby achieving miniaturization of the optical system. This facilitates better convergence of light onto the imaging surface and improves the imaging quality of the optical system.

[0056] By ensuring that the optical system satisfies the relationship 1.45≤SD1 / IMGH≤1.82, the ratio of half the maximum effective aperture of the object side of the first lens to half the image height corresponding to the maximum field of view of the optical system can be reasonably configured. This is beneficial for reasonably controlling the size of the object side of the first lens and realizing the miniaturization of the optical system.

[0057] In one embodiment, the optical system satisfies the relationship: 7.5 ≤ TTL / IMGH ≤ 8.3; where IMGH is half the image height corresponding to the maximum field of view of the optical system. Specifically, the value of TTL / IMGH can be 7.502, 7.591, 7.625, 7.759, 7.822, 7.922, 8.025, 8.144, 8.218, 8.258, etc. By ensuring the optical system satisfies the above relationship, and given a certain image height, the miniaturization requirement of the optical system can be achieved by controlling the ratio of image height to focal length while maintaining image quality.

[0058] In one embodiment, the optical system satisfies the relationship: 0.85 ≤ F / IMGH ≤ 0.95. Specifically, the value of F / IMGH can be 0.866, 0.875, 0.886, 0.890, 0.907, 0.911, 0.918, 0.925, 0.939, 0.948, etc. By ensuring the optical system satisfies the above relationship, the refractive power of the optical system matches the image plane size, thereby improving the imaging quality of the optical system.

[0059] In one embodiment, the optical system satisfies the relationship: 76 ≤ FOV / FNO ≤ 87; where FNO is the aperture number of the optical system. Specifically, the value of FOV / FNO can be 76.364deg, 76.471deg, 76.829deg, 77.647deg, 79.258deg, 80.258deg, 81.295deg, 83.598deg, 84.225deg, 86.250deg, etc. By ensuring the optical system satisfies the above relationship, the ratio of the field of view to the aperture number of the optical system is reasonably configured, achieving a combination effect of a large field of view and a large aperture. The optical system has a reasonable amount of light intake, improving the overall illuminance of the image and making the optical system suitable for different lighting environments.

[0060] In one embodiment, the optical system satisfies the relationship: 2.5 ≤ F3 / F ≤ 3; where F3 is the effective focal length of the third lens. Specifically, the value of F3 / F can be 2.519, 2.546, 2.665, 2.702, 2.785, 2.806, 2.812, 2.843, 2.905, 2.985, etc. By ensuring the optical system satisfies the above relationship and appropriately setting the effective focal length of the third lens, the incident light rays can be effectively collected and compressed, allowing the light to smoothly transition to the rear optical system, reducing aberrations, and thus improving the image quality of the lens.

[0061] In one embodiment, the optical system satisfies the relationship: 1.6 ≤ F4 / F ≤ 2.1; where F4 is the effective focal length of the fourth lens. Specifically, the value of F4 / F can be 1.632, 1.698, 1.711, 1.756, 1.802, 1.849, 1.912, 1.958, 2.008, 2.051, etc. By ensuring the optical system satisfies the above relationship, the refractive power of the fourth lens in the optical system is properly matched, the surface design of the fourth lens is simpler and more flexible, aberrations are reduced, and the overall aberration correction and image quality balance of the optical system are simplified.

[0062] In one embodiment, the optical system satisfies the relationship: -4.5 ≤ F5 / F ≤ -2.7; where F5 is the effective focal length of the fifth lens. Specifically, the value of F5 / F can be -4.307, -4.158, -3.942, -3.758, -3.568, -3.274, -3.025, -2.887, -2.880, -2.879, etc. By ensuring the optical system satisfies the above relationship, the refractive power of the fifth lens in the optical system is properly matched, the surface design of the fifth lens is simpler and more flexible, aberrations are reduced, and the overall aberration correction and image quality balance of the optical system are simplified.

[0063] In one embodiment, the optical system satisfies the relationship: 1.1 ≤ BFL / F ≤ 1.5; where BFL is the distance on the optical axis from the image-side surface of the seventh lens to the imaging surface of the optical system. Specifically, the value of BFL / F can be 1.169, 1.178, 1.185, 1.236, 1.245, 1.287, 1.305, 1.358, 1.415, 1.465, etc. By ensuring that the optical system satisfies the above relationship, it is beneficial to achieve a balance between obtaining good image quality and an easy-to-assemble optical back focal length, ensuring the image quality of the optical system while reducing the design and assembly difficulty of the optical system and improving the yield rate.

[0064] In one embodiment, the optical system satisfies the relationship: 4.2 ≤ CT4 / CT34 ≤ 15; where CT4 is the thickness of the fourth lens along the optical axis, and CT34 is the distance along the optical axis from the image-side surface of the third lens to the object-side surface of the fourth lens. Specifically, the values ​​of CT4 / CT34 can be 4.287, 6.410, 6.717, 6.985, 7.158, 9.327, 10.258, 12.589, 13.258, 14.543, etc. By ensuring the optical system satisfies the above relationship, the thickness of the fourth lens along the optical axis is reasonably set, and the distance between the third and fourth lenses along the optical axis is also reasonably set, which is beneficial for controlling the incident angle of light and maintaining the miniaturization of the optical system.

[0065] In one embodiment, the optical system satisfies the relationship: -2.8 ≤ R7 / R8 ≤ -1.5; where R7 is the radius of curvature of the object-side surface of the fourth lens at the optical axis, and R8 is the radius of curvature of the image-side surface of the fourth lens at the optical axis. Specifically, the values ​​of R7 / R8 can be -2.620, -2.616, -2.582, -2.523, -2.367, -2.025, -1.856, -1.748, -1.625, -1.563, etc. By ensuring that the optical system satisfies the above relationship, it is beneficial to rationally configure the ratio of the radius of curvature of the object-side surface of the fourth lens at the optical axis to that of the image-side surface of the fourth lens at the optical axis, control the shape of the fourth lens, comprehensively balance the spherical aberration, chromatic aberration, and field curvature of the optical system, reduce the risk of ghosting, improve the resolving power of the optical system, and at the same time, reduce the manufacturing difficulty of the fourth lens.

[0066] In one embodiment, the optical system satisfies the relationship: 0.58 ≤ R15 / R16 ≤ 0.85; where R15 is the radius of curvature of the object-side surface of the eighth lens at the optical axis, and R16 is the radius of curvature of the image-side surface of the eighth lens at the optical axis. Specifically, the values ​​of R15 / R16 can be 0.598, 0.604, 0.643, 0.658, 0.684, 0.700, 0.758, 0.785, 0.820, 0.845, etc. By ensuring the optical system satisfies the above relationship, it is beneficial to rationally configure the ratio of the radius of curvature of the object-side surface of the eighth lens at the optical axis to that of the image-side surface of the eighth lens at the optical axis, control the shape of the eighth lens, comprehensively balance the spherical aberration, chromatic aberration, and field curvature of the optical system, reduce the risk of ghosting, improve the resolving power of the optical system, and also help reduce the processing difficulty of the fourth lens.

[0067] In one embodiment, the optical system satisfies the relationship: 2.1 ≤ CT4 / CT5 ≤ 5.4; where CT5 is the thickness of the fifth lens along the optical axis. Specifically, the value of CT4 / CT5 can be 2.118, 2.685, 3.106, 3.785, 4.090, 4.325, 4.681, 4.985, 5.176, 5.321, etc. By ensuring the optical system satisfies the above relationship, the ratio of the thickness of the fourth lens along the optical axis to the thickness of the fifth lens along the optical axis can be reasonably configured. The fourth and fifth lenses can be mutually adjusted, maintaining the miniaturized characteristics of the optical system.

[0068] In one embodiment, the optical system satisfies the relationship: 3.7 ≤ Vd4 / Vd5 ≤ 3.9; where Vd4 is the Abbe number of the fourth lens and Vd5 is the Abbe number of the fifth lens. Specifically, the values ​​of Vd4 / Vd5 can be 3.741, 3.782, 3.800, 3.809, 3.811, 3.825, 3.836, 3.855, 3.782, 3.865, etc. By ensuring that the optical system satisfies the above relationship, the ratio of the Abbe number of the fourth lens to the Abbe number of the fifth lens is within a reasonable range, effectively correcting the axial chromatic aberration of the optical system.

[0069] In one embodiment, the optical system satisfies the relationship: -0.7mm ≤ F6 / Vd6 + F7 / Vd7 ≤ -0.2mm; where F6 is the effective focal length of the sixth lens, Vd6 is the Abbe number of the sixth lens, F7 is the effective focal length of the seventh lens, and Vd7 is the Abbe number of the seventh lens. Specifically, the values ​​of F6 / Vd6 + F7 / Vd7 can be -0.666mm, -0.611mm, -0.512mm, -0.478mm, -0.412mm, -0.354mm, -3.024mm, -0.296mm, -0.237mm, -0.225mm, etc. By ensuring that the optical system satisfies the above relationship, chromatic dispersion of the optical system can be effectively counteracted, which is beneficial for achieving confocal focusing of visible and infrared light in both bands.

[0070] In one embodiment, the optical system satisfies the relationship: 0.17 ≤ SD1 / TTL ≤ 0.25. Specifically, the value of SD1 / TTL can be 0.176, 0.181, 0.191, 0.196, 0.202, 0.205, 0.206, 0.222, 0.235, 0.249, etc. By ensuring the optical system satisfies the above relationship, the ratio of the optical aperture of the first lens to the total length of the optical system can be reasonably configured, which helps to limit the size of the optical system and achieve miniaturization.

[0071] In one embodiment, the optical system satisfies the relationship: 1 ≤ SD11 / SD10 ≤ 1.1; where SD11 is half the maximum effective aperture of the object-side surface of the sixth lens, and SD10 is half the maximum effective aperture of the image-side surface of the fifth lens. Specifically, the values ​​of SD11 / SD10 can be 1.015, 1.029, 1.039, 1.042, 1.058, 1.068, 1.075, 1.092, 1.093, 1.099, etc. By ensuring the optical system satisfies the above relationship, the transition between the fifth and sixth lenses is smooth, reducing the step difference between them, which in turn facilitates the smooth entry of light into the sixth lens and improves the illumination of the optical system.

[0072] In one embodiment, the optical system satisfies the relationship: -8.5 ≤ F123 / F ≤ -3; where F123 is the combined effective focal length of the first, second, and third lenses. Specifically, the value of F123 / F can be -8.101, -7.158, -6.287, -5.527, -5.028, -4.502, -4.172, -3.612, -3.468, -3.382, etc. By ensuring the optical system satisfies the above relationship, the ratio of the combined effective focal length of the first, second, and third lenses to the effective focal length of the optical system can be reasonably configured. This, along with a reasonable matching of the front lens combination focal length of the aperture stop, facilitates better distortion correction and achieves low distortion in the optical system.

[0073] In one embodiment, the optical system satisfies the relationship: 3.4 ≤ F45 / F ≤ 4.7; where F45 is the combined effective focal length of the fourth and fifth lenses. Specifically, the value of F45 / F can be 3.499, 3.587, 3.769, 3.882, 3.952, 4.129, 4.234, 4.358, 4.587, 4.611, etc. By ensuring the optical system satisfies the above relationship, the ratio of the effective focal length of the cemented lens (combination of the fourth and fifth lenses) to the effective focal length of the optical system is rationally configured. This facilitates the correction of chromatic aberration and balances various aberrations, improves the resolving power of the optical system, effectively reduces the tolerance sensitivity of the optical system, and thus enhances the imaging quality of the optical system.

[0074] In one embodiment, the optical system satisfies the relationship: 5.5 ≤ F67 / F ≤ 11; where F67 is the combined effective focal length of the sixth and seventh lenses. Specifically, the value of F67 / F can be 5.508, 6.018, 6.748, 6.876, 7.345, 7.958, 8.258, 9.158, 9.768, 10.567, etc. By ensuring the optical system satisfies the above relationship, the ratio of the effective focal length of the cemented lens (combined with the sixth and seventh lenses) to the effective focal length of the optical system is rationally configured. This allows light to smoothly transition into the rear optical system, which helps balance various aberrations, improves lens resolution, and simultaneously reduces tolerance sensitivity, thereby increasing the production yield of the optical system.

[0075] In one embodiment, the optical system satisfies the relationship: 1.6 ≤ FNO ≤ 1.7; where FNO is the aperture number of the optical system. Specifically, the value of FNO can be 1.600, 1.610, 1.620, 1.640, 1.650, 1.660, 1.670, 1.680, 1.690, 1.700, etc. By ensuring the optical system satisfies the above relationship, the aperture number of the optical system is set within a reasonable range, achieving a combination of a large field of view and a large aperture. This results in a reasonable amount of light entering the optical system, improving the overall illuminance of the image and making the optical system suitable for different lighting environments.

[0076] In one embodiment, the optical system satisfies the relationship: 1.7 ≤ F × tan(FOV / 2) / IMGH ≤ 2.3. Specifically, the value of F × tan(FOV / 2) / IMGH can be 1.747, 1.758, 1.780, 1.788, 1.825, 1.869, 1.969, 2.046, 2.158, 2.255, etc. By ensuring that the optical system satisfies the above relationship, it is helpful to better control the optical distortion of the optical system and improve the resolving power of the optical system.

[0077] In one embodiment, the optical system satisfies the relationship: 2.8 ≤ ∑CT / ∑AT ≤ 4.4; where ∑CT is the sum of the thicknesses of the first to eighth lenses along the optical axis, and ∑AT is the sum of the distances between adjacent lenses along the optical axis. Specifically, the value of ∑CT / ∑AT can be 2.893, 3.263, 3.337, 3.508, 3.784, 3.823, 3.949, 4.125, 4.258, 4.339, etc. By ensuring the optical system satisfies the above relationship, the ratio of the sum of the thicknesses of the first to eighth lenses along the optical axis to the sum of the distances between adjacent lenses along the optical axis can be reasonably configured. This allows for reasonable settings of the thickness of each lens and the distance between adjacent lenses in the optical system, achieving miniaturization of the optical system, improving its manufacturability, and facilitating mutual adjustment of the thicknesses of each lens and the distance between adjacent lenses, thereby reducing aberrations and tolerance sensitivity and improving the imaging quality of the optical system.

[0078] In one embodiment, the optical system satisfies the relationship: -2 ≤ F1 / F ≤ -1.5; where F1 is the effective focal length of the first lens. Specifically, the value of F1 / F can be -1.958, -1.853, -1.805, -1.777, -1.722, -1.689, -1.644, -1.612, -1.593, -1.523, etc. By ensuring the optical system satisfies the above relationship, the refractive power of the first lens in the optical system is properly matched, the surface design of the first lens is simpler and more flexible, enabling the first lens to support a larger field of view and a large aperture; at the same time, it also helps to converge the light rays incident from the first lens to the optical system, delay the incident angle of the light rays, reduce aberrations, and simplify the overall aberration correction and image quality balance of the optical system.

[0079] In one embodiment, the optical system satisfies the relationship: -3.4 ≤ F2 / F ≤ -2.4; where F2 is the effective focal length of the second lens. Specifically, the value of F2 / F can be -3.325, -3.238, -3.105, -3.094, -3.089, -2.987, -2.836, -2.707, -2.601, -2.402, etc. By ensuring the optical system satisfies the above relationship, the refractive power of the second lens in the optical system is properly matched, making the surface design of the second lens simpler and more flexible, reducing aberrations, and simplifying the overall aberration correction and image quality balance of the optical system.

[0080] In one embodiment, the optical system satisfies the relationship: 2.2 ≤ F6 / F ≤ 2.5. Specifically, the value of F6 / F can be 2.293, 2.313, 2.317, 2.358, 2.397, 2.415, 2.449, 2.458, 2.485, 2.495, etc. By ensuring the optical system satisfies the above relationship, it is beneficial to properly match the refractive power of the sixth lens in the optical system, making the surface design of the sixth lens simpler and more flexible, reducing aberrations, and simplifying the overall aberration correction and image quality balance of the optical system.

[0081] In one embodiment, the optical system satisfies the relationship: -4 ≤ F7 / F ≤ -2.5. Specifically, the value of F7 / F can be -3.985, -3.758, -3.697, -3.450, -3.211, -3.115, -3.061, -2.857, -2.759, -2.616, etc. By ensuring the optical system satisfies the above relationship, it is beneficial to achieve proper coordination of the refractive power of the seventh lens within the optical system, making the surface design of the seventh lens simpler and more flexible, reducing aberrations, and simplifying the overall aberration correction and image quality balance of the optical system.

[0082] In one embodiment, the optical system satisfies the relationship: 7 ≤ F8 / F ≤ 18; where F8 is the effective focal length of the eighth lens. Specifically, the value of F8 / F can be 7.054, 8.475, 9.522, 10.132, 11.258, 12.117, 13.598, 14.668, 16.532, 17.325, etc. By ensuring the optical system satisfies the above relationship, the refractive power of the eighth lens in the optical system is properly matched, making the surface design of the eighth lens simpler and more flexible, reducing aberrations, and simplifying the overall aberration correction and image quality balance of the optical system.

[0083] In one embodiment, the optical system satisfies the relationship: 3 ≤ R1 / R2 ≤ 5.2; where R1 is the radius of curvature of the object-side surface of the first lens at the optical axis, and R2 is the radius of curvature of the image-side surface of the first lens at the optical axis. Specifically, the values ​​of R1 / R2 can be 3.391, 3.633, 3.822, 3.880, 4.029, 4.289, 4.514, 4.789, 5.018, 5.159, etc. By ensuring the optical system satisfies the above relationship, it is beneficial to rationally configure the ratio of the radius of curvature of the object-side surface of the first lens at the optical axis to that of the image-side surface of the first lens at the optical axis, control the shape of the first lens, comprehensively balance the spherical aberration, chromatic aberration, and field curvature of the optical system, reduce the risk of ghosting, improve the resolving power of the optical system, and also help reduce the manufacturing difficulty of the first lens.

[0084] In one embodiment, the optical system satisfies the relationship: 0 ≤ R3 / R4 ≤ 0.42; where R3 is the radius of curvature of the object-side surface of the second lens at the optical axis, and R4 is the radius of curvature of the image-side surface of the second lens at the optical axis. Specifically, the value of R3 / R4 can be 0.090, 0.195, 0.208, 0.248, 0.289, 0.358, 0.369, 0.384, 0.402, 0.411, etc. By ensuring the optical system satisfies the above relationship, it is beneficial to rationally configure the ratio of the radius of curvature of the object-side surface of the second lens at the optical axis to that of the image-side surface of the second lens at the optical axis, control the shape of the second lens, comprehensively balance the spherical aberration, chromatic aberration, and field curvature of the optical system, reduce the risk of ghosting, improve the resolving power of the optical system, and also help reduce the manufacturing difficulty of the second lens.

[0085] In one embodiment, the optical system satisfies the relationship: |R5 / R6|≤0.12; where R5 is the radius of curvature of the object-side surface of the third lens at the optical axis, and R6 is the radius of curvature of the image-side surface of the third lens at the optical axis. Specifically, the value of |R5 / R6| can be 0.012, 0.025, 0.035, 0.058, 0.069, 0.078, 0.080, 0.093, 0.112, 0.120, etc. By ensuring the optical system satisfies the above relationship, it is beneficial to rationally configure the ratio of the radius of curvature of the object-side surface of the third lens at the optical axis to that of the image-side surface of the third lens at the optical axis, control the shape of the third lens, comprehensively balance the spherical aberration, chromatic aberration, and field curvature of the optical system, reduce the risk of ghosting, improve the resolving power of the optical system, and also help reduce the manufacturing difficulty of the third lens.

[0086] In one embodiment, the optical system satisfies the relationship: 0.4 ≤ R9 / R10 ≤ 0.55; where R9 is the radius of curvature of the object-side surface of the fifth lens at the optical axis, and R10 is the radius of curvature of the image-side surface of the fifth lens at the optical axis. Specifically, the value of R9 / R10 can be 0.403, 0.423, 0.448, 0.461, 0.474, 0.478, 0.498, 0.512, 0.534, 0.548, etc. By ensuring the optical system satisfies the above relationship, it is beneficial to rationally configure the ratio of the radius of curvature of the object-side surface of the fifth lens at the optical axis to that of the image-side surface of the fifth lens at the optical axis, control the shape of the fifth lens, comprehensively balance the spherical aberration, chromatic aberration, and field curvature of the optical system, reduce the risk of ghosting, improve the resolving power of the optical system, and also help reduce the manufacturing difficulty of the fifth lens.

[0087] In one embodiment, the optical system satisfies the relationship: -1.2 ≤ R11 / R12 ≤ -0.8; where R11 is the radius of curvature of the object-side surface of the sixth lens at the optical axis, and R12 is the radius of curvature of the image-side surface of the sixth lens at the optical axis. Specifically, the values ​​of R11 / R12 can be -1.117, -1.089, -1.000, -0.986, -0.965, -0.948, -0.905, -0.862, -0.841, -0.805, etc. By ensuring that the optical system satisfies the above relationship, it is beneficial to rationally configure the ratio of the radius of curvature of the object-side surface of the sixth lens at the optical axis to that of the image-side surface of the sixth lens at the optical axis, control the shape of the sixth lens, comprehensively balance the spherical aberration, chromatic aberration, and field curvature of the optical system, reduce the risk of ghosting, improve the resolving power of the optical system, and also help reduce the manufacturing difficulty of the sixth lens.

[0088] In one embodiment, the optical system satisfies the relationship: 0.1 ≤ |R13 / R14| ≤ 0.4; where R13 is the radius of curvature of the object-side surface of the seventh lens at the optical axis, and R14 is the radius of curvature of the image-side surface of the seventh lens at the optical axis. Specifically, the value of |R13 / R14| can be 0.116, 0.155, 0.157, 0.192, 0.212, 0.238, 0.268, 0.305, 0.350, 0.370, etc. By ensuring the optical system satisfies the above relationship, it is beneficial to rationally configure the ratio of the radius of curvature of the object-side surface of the seventh lens at the optical axis to that of the image-side surface of the seventh lens at the optical axis, control the shape of the seventh lens, comprehensively balance the spherical aberration, chromatic aberration, and field curvature of the optical system, reduce the risk of ghosting, improve the resolving power of the optical system, and also help reduce the manufacturing difficulty of the seventh lens.

[0089] In some embodiments, the optical system further includes a filter, which can be an infrared cut-off filter, an infrared bandpass filter, or a dual-pass filter. In this application, a dual-pass filter is selected, which can simultaneously transmit high levels of visible light and a portion of infrared light, thereby enabling different wavelength selection. This allows for both visible light imaging and infrared imaging, making it usable day and night. Alternatively, an infrared cut-off filter can be used to filter out infrared light, allowing only visible light to pass through, making the image more visually pleasing to the human eye. An infrared bandpass filter can also be used, fixedly positioned relative to the lenses in the optical system. The infrared bandpass filter allows infrared light of the center wavelength to pass through, filtering out background stray light, and is used in infrared lenses. Furthermore, the filter can be assembled together with the lenses as part of the optical system. In other embodiments, the filter can be a component independent of the optical system, installed between the optical system and the photosensitive chip during assembly. It is understood that the filter can be made of optical glass with a coating, colored glass, or other materials, and can be selected according to actual needs. This embodiment does not impose specific limitations. In other embodiments, the filtering effect can also be achieved by providing a filter coating on at least one of the first to eighth lenses.

[0090] In some embodiments, at least one lens in the optical system may have a spherical surface. A spherical surface design reduces the difficulty and cost of lens fabrication. In some embodiments, at least one lens in the optical system may also have an aspherical surface. A lens is said to have an aspherical surface when at least one surface (object-side or image-side) is aspherical. In some embodiments, both the object-side and image-side surfaces of each lens may be designed as aspherical. Aspherical design helps the optical system more effectively eliminate aberrations and improve image quality. In some embodiments, to balance fabrication cost, fabrication difficulty, image quality, and assembly difficulty, the surface design of each lens in the optical system may be a combination of spherical and aspherical surfaces. In this application, the second and eighth lenses have aspherical surfaces, while the first, third, fourth, fifth, sixth, and seventh lenses have spherical surfaces.

[0091] In some embodiments, at least one lens in the optical system is made of glass (GL). For example, the first lens L1 closest to the object side can be made of glass. Utilizing the temperature drift reduction effect of the glass material in the first lens L1, the impact of ambient temperature changes on the optical system can be effectively reduced, thereby maintaining good and stable image quality. In some embodiments, at least one lens in the optical system can also be made of plastic (PC), such as polycarbonate or resin. Lenses made of plastic can reduce the production cost of the optical system, while lenses made of glass can withstand high or low temperatures and have excellent optical performance and better stability. In some embodiments, the optical system can use lenses of different materials, such as a combination of glass and plastic lenses. However, the specific configuration can be determined according to actual needs and will not be exhaustively listed here.

[0092] First Embodiment

[0093] Please refer to Figure 1 The optical system 10 of this embodiment includes, from the object side to the image side, sequentially along the optical axis O:

[0094] The first lens L1 has negative refractive power. The object side S1 of the first lens L1 is convex near the optical axis O, and the image side S2 is concave near the optical axis O.

[0095] The second lens L2 has negative refractive power. The object side S3 of the second lens L2 is concave near the optical axis O, and the image side S4 is convex near the optical axis O.

[0096] The third lens L3 has positive refractive power. The object side S5 of the third lens L3 is convex near the optical axis O, and the image side S6 is convex near the optical axis O.

[0097] The fourth lens L4 has positive refractive power. The object side S7 of the fourth lens L4 is convex near the optical axis O, and the image side S8 is convex near the optical axis O.

[0098] The fifth lens L5 has negative refractive power. The object side S9 of the fifth lens L5 is concave near the optical axis O, and the image side S10 is convex near the optical axis O.

[0099] The sixth lens L6 has positive refractive power. The object side S11 of the sixth lens L6 is convex near the optical axis O, and the image side S12 is convex near the optical axis O.

[0100] The seventh lens L7 has negative refractive power. The object side S13 of the seventh lens L7 is concave near the optical axis O, and the image side S14 is concave near the optical axis O.

[0101] The eighth lens L8 has positive refractive power. The object side S15 of the eighth lens L8 is convex near the optical axis O, and the image side S16 is concave near the optical axis O.

[0102] In this embodiment, the optical system 10 further includes, but is not limited to, an aperture stop STO, an IR filter, a protective glass CG, and an imaging surface IMG. The aperture stop STO is disposed between the image-side surface of the third lens L3 and the object-side surface of the fourth lens L4 in the optical system 10, and is used to control the amount of light entering the system. The IR filter is disposed between the eighth lens L8 and the protective glass CG, and includes an object-side surface S17 and an image-side surface S18. The IR filter is a dual-pass filter, capable of simultaneously transmitting high levels of visible light and transmitting a portion of infrared light, thereby enabling selection of different wavelengths. It can achieve both visible light imaging and infrared imaging, thus achieving day and night usability. The material of the dual-pass filter includes, but is not limited to, glass or plastic. The dual-pass filter can be configured as an integral structure. In some embodiments, the dual-pass filter includes a filter body and a coating disposed on the filter body. The protective glass CG is disposed between the IR filter and the imaging surface IMG, and includes an object-side surface S19 and an image-side surface S20. The first lens L1 to the eighth lens L8 can be made of glass or plastic. The effective pixel area of ​​the photosensitive chip is located on the imaging surface (IMG). An infrared photosensitive chip is disposed at the IMG of the imaging surface. The photosensitive chip captures different wavelength information of the object for subsequent processing. In some embodiments, the optical system 10 may include, but is not limited to, at least one of an aperture stop (STO), an infrared filter (IR), a protective glass (CG), and an imaging surface (IMG).

[0103] Table 1a shows the parameters of the optical system 10 of the first embodiment of this application, where the Y-radius is the radius of curvature of the object-side or image-side surface of the corresponding surface number at the optical axis O. Surface numbers S1 and S2 are the object-side surface S1 and image-side surface S2 of the first lens L1, respectively; that is, in the same lens, the surface with the smaller surface number is the object-side surface, and the surface with the larger surface number is the image-side surface. The first value in the "thickness" parameter column of the first lens L1 is the thickness of the lens on the optical axis O, and the second value is the distance from the image-side surface of the lens to the next surface in the image-side direction on the optical axis O. The focal length, material refractive index, and Abbe number are all obtained using visible light with a reference wavelength of 555 nm, and the units of Y-radius, thickness, and effective focal length are all millimeters (mm).

[0104] Table 1a

[0105]

[0106] Wherein, F is the effective focal length of the optical system 10, FNO is the aperture number of the optical system 10, FOV is the maximum field of view of the optical system 10, TTL is the distance from the object side of the first lens to the imaging surface on the optical axis O, and IMGH is half of the image height corresponding to the maximum field of view of the optical system.

[0107] In this embodiment, both the object-side and image-side surfaces of the second lens L2 and the eighth lens L8 are aspherical. The surface shape x of the aspherical surface can be defined using, but is not limited to, the following aspherical formula:

[0108]

[0109] Where x is the distance from the corresponding point on the aspherical surface to the plane tangent to the vertex of the surface, h is the distance from the corresponding point on the aspherical surface to the optical axis O, c is the curvature of the vertex of the aspherical surface, k is the conic coefficient, and Ai is the coefficient corresponding to the i-th higher-order term in the aspherical surface shape formula. Table 1b gives the higher-order coefficients k, A4, A6, A8, A10, A12, A14, A16, A18, and A20 of the aspherical mirrors S3, S4, S15, and S16 that can be used in the first embodiment.

[0110] Table 1b

[0111]

[0112] Figure 2 Figure (a) shows the longitudinal spherical aberration curves of the optical system 10 of the first embodiment at wavelengths of 900.0000 nm, 870.0000 nm, 850.0000 nm, 830.0000 nm, 800.0000 nm, 660.0000 nm, 610.0000 nm, 555.0000 nm, 510.0000 nm, and 470.0000 nm. The horizontal axis along the X-axis represents the focal point shift, i.e., the distance (in mm) from the imaging plane to the intersection of the light ray and the optical axis O. The vertical axis along the Y-axis represents the normalized field of view. The longitudinal spherical aberration curves represent the deviation of the converging focal point of light rays of different wavelengths after passing through the lenses of the optical system 10. Figure 2 As can be seen in (a), the convergence focal point deviation of each wavelength of light in the first embodiment tends to be consistent, and the blur spots or color halo in the image are effectively suppressed by the optical system 10, indicating that the imaging quality of the optical system 10 in this embodiment is good.

[0113] Figure 2Figure (b) also shows an astigmatism curve of the optical system 10 of the first embodiment at a wavelength of 555.0000 nm, where the horizontal axis along the X-axis represents the focal shift and the vertical axis along the Y-axis represents the image height, both in mm. The S-curve in the astigmatism curve represents the sagittal field curvature at 555.0000 nm, and the T-curve represents the meridional field curvature at 555.0000 nm. Figure 2 As can be seen in (b), the field curvature of the optical system 10 is small, and the field curvature and astigmatism of each field of view are well corrected, with clear imaging at the center and edge of the field of view.

[0114] Figure 2 Image (c) also shows the distortion curve of the optical system 10 of the first embodiment at a wavelength of 555.0000 nm. The horizontal axis along the X-axis represents the distortion value, and the vertical axis along the Y-axis represents the field of view, in degrees (deg). The distortion curve represents the distortion magnitude corresponding to different field of view angles. Figure 2 As can be seen in (c), at a wavelength of 555.0000 nm, the image distortion caused by the main beam is small, and the imaging quality of the system is excellent.

[0115] Depend on Figure 2 (a) Figure 2 (b) and Figure 2 As can be seen from (c), the optical system 10 of this embodiment has small aberrations, good imaging quality, and excellent imaging performance.

[0116] Second Embodiment

[0117] Please refer to Figure 3 The optical system 10 of this embodiment includes, from the object side to the image side, sequentially along the optical axis O:

[0118] The first lens L1 has negative refractive power. The object side S1 of the first lens L1 is convex near the optical axis O, and the image side S2 is concave near the optical axis O.

[0119] The second lens L2 has negative refractive power. The object side S3 of the second lens L2 is concave near the optical axis O, and the image side S4 is convex near the optical axis O.

[0120] The third lens L3 has positive refractive power. The object side S5 of the third lens L3 is convex near the optical axis O, and the image side S6 is convex near the optical axis O.

[0121] The fourth lens L4 has positive refractive power. The object side S7 of the fourth lens L4 is convex near the optical axis O, and the image side S8 is convex near the optical axis O.

[0122] The fifth lens L5 has negative refractive power. The object side S9 of the fifth lens L5 is concave near the optical axis O, and the image side S10 is convex near the optical axis O.

[0123] The sixth lens L6 has positive refractive power. The object side S11 of the sixth lens L6 is convex near the optical axis O, and the image side S12 is convex near the optical axis O.

[0124] The seventh lens L7 has negative refractive power. The object side S13 of the seventh lens L7 is concave near the optical axis O, and the image side S14 is convex near the optical axis O.

[0125] The eighth lens L8 has positive refractive power. The object side S15 of the eighth lens L8 is convex near the optical axis O, and the image side S16 is concave near the optical axis O.

[0126] The other structures of the second embodiment are the same as those of the first embodiment, and can be referred to accordingly.

[0127] Table 2a shows the parameters of the optical system 10 in this embodiment. The meanings of each parameter are the same as those in the first embodiment.

[0128] Table 2a

[0129]

[0130] Table 2b gives the higher-order coefficients that can be used for each aspherical mirror in the second embodiment, wherein each aspherical surface shape can be defined by the formula given in the first embodiment.

[0131] Table 2b

[0132]

[0133] Figure 4 (a) Figure 4 (b) Figure 4 Image (c) shows the longitudinal spherical aberration curve, astigmatism curve, and distortion curve of the optical system 10 of the second embodiment. The longitudinal spherical aberration curve represents the deviation of the converging focal point of light rays of different wavelengths after passing through the lenses of the optical system 10; the astigmatism curve represents the meridional field curvature and sagittal field curvature; and the distortion curve represents the distortion magnitude corresponding to different field angles. Figure 4 As can be seen from the aberration diagram, the longitudinal spherical aberration, field curvature, and distortion of the optical system 10 are all well controlled, thus the optical system 10 of this embodiment has good imaging quality.

[0134] Third Embodiment

[0135] Please refer to Figure 5 The optical system 10 of this embodiment includes, from the object side to the image side, sequentially along the optical axis O:

[0136] The first lens L1 has negative refractive power. The object side S1 of the first lens L1 is convex near the optical axis O, and the image side S2 is concave near the optical axis O.

[0137] The second lens L2 has negative refractive power. The object side S3 of the second lens L2 is concave near the optical axis O, and the image side S4 is convex near the optical axis O.

[0138] The third lens L3 has positive refractive power. The object side S5 of the third lens L3 is convex near the optical axis O, and the image side S6 is convex near the optical axis O.

[0139] The fourth lens L4 has positive refractive power. The object side S7 of the fourth lens L4 is convex near the optical axis O, and the image side S8 is convex near the optical axis O.

[0140] The fifth lens L5 has negative refractive power. The object side S9 of the fifth lens L5 is concave near the optical axis O, and the image side S10 is convex near the optical axis O.

[0141] The sixth lens L6 has positive refractive power. The object side S11 of the sixth lens L6 is convex near the optical axis O, and the image side S12 is convex near the optical axis O.

[0142] The seventh lens L7 has negative refractive power. The object side S13 of the seventh lens L7 is concave near the optical axis O, and the image side S14 is convex near the optical axis O.

[0143] The eighth lens L8 has positive refractive power. The object side S15 of the eighth lens L8 is convex near the optical axis O, and the image side S16 is concave near the optical axis O.

[0144] The other structures of the third embodiment are the same as those of the first embodiment, and can be referred to accordingly.

[0145] Table 3a shows the parameters of the optical system 10 in this embodiment. The focal length, material refractive index and Abbe number are obtained using visible light with a reference wavelength of 800 nm. The units for Y radius, thickness and effective focal length are millimeters (mm). The meanings of the other parameters are the same as those in the first embodiment.

[0146] Table 3a

[0147]

[0148] Table 3b gives the higher-order coefficients that can be used for each aspherical mirror in the third embodiment, wherein each aspherical surface shape can be defined by the formula given in the first embodiment.

[0149] Table 3b

[0150]

[0151] Figure 6 (a) Figure 6 (b) Figure 6 Image (c) shows the longitudinal spherical aberration curve, astigmatism curve, and distortion curve of the optical system 10 of the third embodiment. The longitudinal spherical aberration curve represents the deviation of the converging focal point of light rays of different wavelengths after passing through the lenses of the optical system 10; the astigmatism curve represents the meridional field curvature and sagittal field curvature; and the distortion curve represents the distortion magnitude corresponding to different field angles. Figure 6 As can be seen from the aberration diagram, the longitudinal spherical aberration, field curvature, and distortion of the optical system 10 are all well controlled, thus the optical system 10 of this embodiment has good imaging quality.

[0152] Fourth embodiment

[0153] Please refer to Figure 7 The optical system 10 of this embodiment includes, from the object side to the image side, sequentially along the optical axis O:

[0154] The first lens L1 has negative refractive power. The object side S1 of the first lens L1 is convex near the optical axis O, and the image side S2 is concave near the optical axis O.

[0155] The second lens L2 has negative refractive power. The object side S3 of the second lens L2 is concave near the optical axis O, and the image side S4 is convex near the optical axis O.

[0156] The third lens L3 has positive refractive power. The object side S5 of the third lens L3 is convex near the optical axis O, and the image side S6 is convex near the optical axis O.

[0157] The fourth lens L4 has positive refractive power. The object side S7 of the fourth lens L4 is convex near the optical axis O, and the image side S8 is convex near the optical axis O.

[0158] The fifth lens L5 has negative refractive power. The object side S9 of the fifth lens L5 is concave near the optical axis O, and the image side S10 is convex near the optical axis O.

[0159] The sixth lens L6 has positive refractive power. The object side S11 of the sixth lens L6 is convex near the optical axis O, and the image side S12 is convex near the optical axis O.

[0160] The seventh lens L7 has negative refractive power. The object side S13 of the seventh lens L7 is concave near the optical axis O, and the image side S14 is convex near the optical axis O.

[0161] The eighth lens L8 has positive refractive power. The object side S15 of the eighth lens L8 is convex near the optical axis O, and the image side S16 is concave near the optical axis O.

[0162] The other structures of the fourth embodiment are the same as those of the first embodiment, and can be referred to accordingly.

[0163] Table 4a shows the parameters of the optical system 10 in this embodiment. The focal length, material refractive index and Abbe number are obtained using visible light with a reference wavelength of 800 nm. The units for Y radius, thickness and effective focal length are millimeters (mm). The meanings of the other parameters are the same as those in the first embodiment.

[0164] Table 4a

[0165]

[0166] Table 4b gives the higher-order coefficients that can be used for each aspherical mirror in the fourth embodiment, wherein each aspherical surface shape can be defined by the formula given in the first embodiment.

[0167] Table 4b

[0168]

[0169] Figure 8 (a) Figure 8 (b) Figure 8 Image (c) shows the longitudinal spherical aberration curve, astigmatism curve, and distortion curve of the optical system 10 of the fourth embodiment. The longitudinal spherical aberration curve represents the deviation of the converging focal point of light rays of different wavelengths after passing through the lenses of the optical system 10; the astigmatism curve represents the meridional field curvature and sagittal field curvature; and the distortion curve represents the distortion magnitude corresponding to different field angles. Figure 8 As can be seen from the aberration diagram, the longitudinal spherical aberration, field curvature, and distortion of the optical system 10 are all well controlled, thus the optical system 10 of this embodiment has good imaging quality.

[0170] Fifth embodiment

[0171] Please refer to Figure 9 The optical system 10 of this embodiment includes, from the object side to the image side, sequentially along the optical axis O:

[0172] The first lens L1 has negative refractive power. The object side S1 of the first lens L1 is convex near the optical axis O, and the image side S2 is concave near the optical axis O.

[0173] The second lens L2 has negative refractive power. The object side S3 of the second lens L2 is concave near the optical axis O, and the image side S4 is convex near the optical axis O.

[0174] The third lens L3 has positive refractive power. The object side S5 of the third lens L3 is convex near the optical axis O, and the image side S6 is convex near the optical axis O.

[0175] The fourth lens L4 has positive refractive power. The object side S7 of the fourth lens L4 is convex near the optical axis O, and the image side S8 is convex near the optical axis O.

[0176] The fifth lens L5 has negative refractive power. The object side S9 of the fifth lens L5 is concave near the optical axis O, and the image side S10 is convex near the optical axis O.

[0177] The sixth lens L6 has positive refractive power. The object side S11 of the sixth lens L6 is convex near the optical axis O, and the image side S12 is convex near the optical axis O.

[0178] The seventh lens L7 has negative refractive power. The object side S13 of the seventh lens L7 is concave near the optical axis O, and the image side S14 is convex near the optical axis O.

[0179] The eighth lens L8 has positive refractive power. The object side S15 of the eighth lens L8 is convex near the optical axis O, and the image side S16 is concave near the optical axis O.

[0180] The other structures of the fifth embodiment are the same as those of the first embodiment, and can be referred to accordingly.

[0181] Table 5a shows the parameters of the optical system 10 in this embodiment. The meanings of each parameter are the same as those in the first embodiment.

[0182] Table 5a

[0183]

[0184] Table 5b gives the higher-order coefficients that can be used for each aspherical mirror in the fifth embodiment, wherein each aspherical surface shape can be defined by the formula given in the first embodiment.

[0185] Table 5b

[0186]

[0187] Figure 10 (a) Figure 10 (b) Figure 10 Image (c) shows the longitudinal spherical aberration curve, astigmatism curve, and distortion curve of the optical system 10 of the fifth embodiment. The longitudinal spherical aberration curve represents the deviation of the converging focal point of light rays of different wavelengths after passing through the lenses of the optical system 10; the astigmatism curve represents the meridional field curvature and sagittal field curvature; and the distortion curve represents the distortion magnitude corresponding to different field angles. Figure 10 As can be seen from the aberration diagram, the longitudinal spherical aberration, field curvature, and distortion of the optical system 10 are all well controlled, thus the optical system 10 of this embodiment has good imaging quality.

[0188] Sixth Embodiment

[0189] Please refer to Figure 11 The optical system 10 of this embodiment includes, from the object side to the image side, sequentially along the optical axis O:

[0190] The first lens L1 has negative refractive power. The object side S1 of the first lens L1 is convex near the optical axis O, and the image side S2 is concave near the optical axis O.

[0191] The second lens L2 has negative refractive power. The object side S3 of the second lens L2 is concave near the optical axis O, and the image side S4 is convex near the optical axis O.

[0192] The third lens L3 has positive refractive power. The object side S5 of the third lens L3 is convex near the optical axis O, and the image side S6 is concave near the optical axis O.

[0193] The fourth lens L4 has positive refractive power. The object side S7 of the fourth lens L4 is convex near the optical axis O, and the image side S8 is convex near the optical axis O.

[0194] The fifth lens L5 has negative refractive power. The object side S9 of the fifth lens L5 is concave near the optical axis O, and the image side S10 is convex near the optical axis O.

[0195] The sixth lens L6 has positive refractive power. The object side S11 of the sixth lens L6 is convex near the optical axis O, and the image side S12 is convex near the optical axis O.

[0196] The seventh lens L7 has negative refractive power. The object side S13 of the seventh lens L7 is concave near the optical axis O, and the image side S14 is concave near the optical axis O.

[0197] The eighth lens L8 has positive refractive power. The object side S15 of the eighth lens L8 is convex near the optical axis O, and the image side S16 is concave near the optical axis O.

[0198] The other structures of the sixth embodiment are the same as those of the first embodiment, and can be referred to accordingly.

[0199] Table 6a shows the parameters of the optical system 10 in this embodiment. The meanings of each parameter are the same as those in the first embodiment.

[0200] Table 6a

[0201]

[0202] Table 6b gives the higher-order coefficients that can be used for each aspherical mirror in the sixth embodiment, wherein each aspherical surface shape can be defined by the formula given in the first embodiment.

[0203] Table 6b

[0204]

[0205] Figure 12 (a) Figure 12 (b) Figure 12 Image (c) shows the longitudinal spherical aberration curve, astigmatism curve, and distortion curve of the optical system 10 of the sixth embodiment. The longitudinal spherical aberration curve represents the deviation of the converging focal point of light rays of different wavelengths after passing through the lenses of the optical system 10; the astigmatism curve represents the meridional field curvature and sagittal field curvature; and the distortion curve represents the distortion magnitude corresponding to different field angles. Figure 12 As can be seen from the aberration diagram, the longitudinal spherical aberration, field curvature, and distortion of the optical system 10 are all well controlled, thus the optical system 10 of this embodiment has good imaging quality.

[0206] Table 7 shows the values ​​of FOV, TTL / F, TTL / IMGH, F / IMGH, FOV / FNO, F3 / F, F4 / F, F5 / F, BFL / F, CT4 / CT34, R7 / R8, R15 / R16, CT4 / CT5, Vd4 / Vd5, F6 / Vd6+F7 / Vd7, SD1 / IMGH, SD1 / TTL, SD11 / SD10, F123 / F, F45 / F, F67 / F, FNO, F*tan(FOV / 2) / IMGH, ∑CT / ∑AT, F1 / F, F2 / F, F6 / F, F7 / F, F8 / F, R1 / R2, R3 / R4, |R5 / R6|, R9 / R10, R11 / R12, and |R13 / R14| in the optical system 10 of the first to sixth embodiments.

[0207] Table 7

[0208]

[0209] As shown in Table 7, the optical systems of the first to sixth embodiments all satisfy the following relationships: 125≤FOV≤139, 8.5≤TTL / F≤9.1, 7.5≤TTL / IMGH≤8.3, 0.85≤F / IMGH≤0.95, 76deg≤FOV / FNO≤87deg, 2.5≤F3 / F≤3, 1.6≤F4 / F≤2.1, -4.5≤F5 / F ≤-2.7, 1.1≤BFL / F≤1.5, 4.2≤CT4 / CT34≤15, -2.8≤R7 / R8≤-1.5, 0.58≤R15 / R16≤0.85, 2. 1≤CT4 / CT5≤5.4, 3.7≤Vd4 / Vd5≤3.9, -0.7mm≤F6 / Vd6+F7 / Vd7≤-0.2mm, 1.45≤SD1 / IMGH≤ 1.82, 0.17≤SD1 / TTL≤0.25, 1≤SD11 / SD10≤1.1, -8.5≤F123 / F≤-3, 3.4≤F45 / F≤4.7, 5.5≤ F67 / F≤11, 1.6≤FNO≤1.7, 1.7≤F×tan(FOV / 2) / IMGH≤2.3, 2.8≤∑CT / ∑AT≤4.4, -2≤F1 / F≤- 1.5, -3.4≤F2 / F≤-2.4, 2.2≤F6 / F≤2.5, -4≤F7 / F≤-2.5, 7≤F8 / F≤18, 3≤R1 / R2≤5.2, 0≤R3 / R4≤0.42, |R5 / R6|≤0.12, 0.4≤R9 / R10≤0.55, -1.2≤R11 / R12≤-0.8 and 0.1≤|R13 / R14|≤0.4.

[0210] Please see Figure 13 The present invention also provides a camera module 20, which includes a photosensitive chip 21 and an optical system 10 as described in any of the above embodiments. The photosensitive chip 21 is disposed on the image side of the optical system 10. The photosensitive surface of the photosensitive chip 21 is located on the imaging surface of the optical system 10, and light rays from an object incident on the photosensitive surface through a lens can be converted into electrical signals for an image. The photosensitive chip 21 can be a complementary metal-oxide-semiconductor (CMOS) or a charge-coupled device (CCD). The camera module 20 can be an imaging module integrated into an electronic device 30 or a separate lens. By incorporating the optical system 10 provided by the present invention into the camera module 20, the camera module 20 can achieve a large field of view and miniaturization through reasonable design of the surface shape and refractive power of each lens in the optical system 10.

[0211] Please see Figure 14The present invention also provides an electronic device 30, which includes a housing 31 and the aforementioned camera module 20, wherein the camera module 20 is disposed within the housing 31. This electronic device 30 includes, but is not limited to, automobiles, monitoring equipment, smartphones, computers, and smartwatches. By incorporating the camera module 20 provided by the present invention into the electronic device 30, the electronic device 30 achieves a large field of view and miniaturization.

[0212] The above description discloses only some preferred embodiments of the present invention, and should not be construed as limiting the scope of the present invention. Those skilled in the art can understand that implementing all or part of the above embodiments and making equivalent changes in accordance with the claims of the present invention still fall within the scope of the present invention.

Claims

1. An optical system, characterized in that, It includes eight lenses with refractive power, arranged sequentially along the optical axis from the object side to the image side: A first lens, the first lens having negative refractive power, the object side of the first lens being convex near the optical axis, and the image side of the first lens being concave near the optical axis; The second lens has negative refractive power, the object side of the second lens is concave near the optical axis, and the image side of the second lens is convex near the optical axis. The third lens has positive refractive power, and the object side of the third lens is convex near the optical axis; The fourth lens has positive refractive power, the object side of the fourth lens is convex near the optical axis, and the image side of the fourth lens is convex near the optical axis. The fifth lens has negative refractive power, the object side of the fifth lens is concave near the optical axis, and the image side of the fifth lens is convex near the optical axis; The sixth lens has positive refractive power, the object side of the sixth lens is convex near the optical axis, and the image side of the sixth lens is convex near the optical axis. The seventh lens has negative refractive power, and the object side of the seventh lens is concave near the optical axis; The eighth lens has positive refractive power, the object side of the eighth lens is convex near the optical axis, and the image side of the eighth lens is concave near the optical axis. The optical system satisfies the following relationships: 125deg≤FOV≤139deg, 8.5≤TTL / F≤9.1, 1.45≤SD1 / IMGH≤1.82; Wherein, FOV is the maximum field of view of the optical system, TTL is the distance on the optical axis from the object side of the first lens to the imaging surface, F is the effective focal length of the optical system, SD1 is half of the maximum effective aperture of the object side of the first lens, and IMGH is half of the image height corresponding to the maximum field of view of the optical system.

2. The optical system as described in claim 1, characterized in that, The optical system satisfies the following relationship: 7.5 ≤ TTL / IMGH ≤ 8.3; and / or, 0.85 ≤ F / IMGH ≤ 0.95; and / or, 76deg≤FOV / FNO≤87deg; Wherein, IMGH is half the image height corresponding to the maximum field of view of the optical system, and FNO is the aperture number of the optical system.

3. The optical system as described in claim 1, characterized in that, The optical system satisfies the following relationship: 2.5≤F3 / F≤3; and / or, 1.6 ≤ F4 / F ≤ 2.1; and / or, -4.5≤F5 / F≤-2.7; and / or, 1.1≤BFL / F≤1.5; Wherein, F3 is the effective focal length of the third lens, F4 is the effective focal length of the fourth lens, F5 is the effective focal length of the fifth lens, and BFL is the distance from the image side of the eighth lens to the imaging surface of the optical system on the optical axis.

4. The optical system as claimed in claim 1, characterized in that, The optical system satisfies the following relationship: 4.2≤CT4 / CT34≤15; and / or, -2.8≤R7 / R8≤-1.5; and / or, 0.58≤R15 / R16≤0.85; Wherein, CT4 is the thickness of the fourth lens on the optical axis, CT34 is the distance from the image side of the third lens to the object side of the fourth lens on the optical axis, R7 is the radius of curvature of the object side of the fourth lens on the optical axis, R8 is the radius of curvature of the image side of the fourth lens on the optical axis, R15 is the radius of curvature of the object side of the eighth lens on the optical axis, and R16 is the radius of curvature of the image side of the eighth lens on the optical axis.

5. The optical system as claimed in claim 1, characterized in that, The optical system satisfies the following relationship: 2.1≤CT4 / CT5≤5.4; and / or, 3.7≤Vd4 / Vd5≤3.9; and / or, -0.7mm≤F6 / Vd6+F7 / Vd7≤-0.2mm; Wherein, CT4 is the thickness of the fourth lens on the optical axis, CT5 is the thickness of the fifth lens on the optical axis, Vd4 is the Abbe number of the fourth lens, Vd5 is the Abbe number of the fifth lens, F6 is the effective focal length of the sixth lens, Vd6 is the Abbe number of the sixth lens, F7 is the effective focal length of the seventh lens, and Vd7 is the Abbe number of the seventh lens.

6. The optical system as claimed in claim 1, characterized in that, The optical system satisfies the following relationship: 0.17≤SD1 / TTL≤0.25; and / or, 1≤SD11 / SD10≤1.1; Wherein, SD11 is half of the maximum effective aperture of the object side of the sixth lens, and SD10 is half of the maximum effective aperture of the image side of the fifth lens.

7. The optical system as claimed in claim 1, characterized in that, The optical system satisfies the following relationship: -8.5≤F123 / F≤-3; and / or, 3.4≤F45 / F≤4.7; and / or, 5.5≤F67 / F≤11; Wherein, F123 is the combined effective focal length of the first lens, the second lens and the third lens, F45 is the combined effective focal length of the fourth lens and the fifth lens, and F67 is the combined effective focal length of the sixth lens and the seventh lens.

8. The optical system as claimed in claim 1, characterized in that, The optical system satisfies the following relationship: 1.6 ≤ FNO ≤ 1.7; and / or, 1.7 ≤ F × tan(FOV / 2) / IMGH ≤ 2.3; and / or, 2.8 ≤ ∑CT / ∑AT ≤ 4.4; Wherein, FNO is the aperture number of the optical system, IMGH is half the image height corresponding to the maximum field of view of the optical system, ∑CT is the sum of the thicknesses of the first lens to the eighth lens on the optical axis, and ∑AT is the sum of the interval distances between two adjacent lenses on the optical axis.

9. A camera module, characterized in that, It includes a photosensitive chip and an optical system according to any one of claims 1 to 8, wherein the photosensitive chip is located on the image side of the optical system.

10. An electronic device, characterized in that, It includes a housing and the camera module as described in claim 9, wherein the camera module is disposed within the housing.

Images