Optical system, camera module and electronic equipment

Abstract

An optical system, a camera module and an electronic device, the optical system sequentially comprising from an object side to an image side along an optical axis: a first lens to a sixth lens having refractive power, the first lens, the fourth lens and the sixth lens having negative refractive power, and the second lens, the third lens and the fifth lens having positive refractive power, the object-side surface of the first lens, the object-side surface and the image-side surface of the fourth lens and the object-side surface of the sixth lens are concave surfaces near the optical axis, and the image-side surface of the first lens, the object-side surface and the image-side surface of the second lens, the object-side surface and the image-side surface of the third lens and the object-side surface and the image-side surface of the fifth lens are convex surfaces near the optical axis. Through reasonable design of the surface type and the refractive power of each lens of the optical system, the optical system has the characteristics of miniaturization, high pixel and large field angle.

Description

Technical Field

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

[0002] Thanks to the rapid development of automobile assisted driving systems in recent years, optical lenses have been widely used in automobiles. Among them, optical lenses can be widely used in vehicle-mounted reversing visual systems, driving recorders, automatic parking and panoramic parking systems, road finding systems, etc.

[0003] The vehicle-mounted lens is a key component for the automatic driving assistance system to obtain external information. For safety reasons, the performance requirements for the vehicle-mounted lens are very strict. First, the vehicle-mounted lens needs to have a clearer and wider field of view to fully collect environmental information and ensure driving safety; secondly, the vehicle-mounted lens needs to be able to capture both close and far objects, and both can be clearly imaged; in addition, the vehicle-mounted lens should also meet the requirements of being light and thin.

[0004] Therefore, a miniaturized, high-pixel, and large-field-of-view optical lens is needed to meet the needs of autonomous driving applications. Summary of the invention

[0005] The purpose of the present invention is to provide an optical system, a camera module and an electronic device to solve the problem that the vehicle-mounted optical system needs to have miniaturization, high pixels and a large field of view.

[0006] To achieve the purpose of the present invention, the present invention provides the following technical solutions: In a first aspect, the present invention provides an optical system, comprising six lenses with refractive power, which include, in order from the object side to the image side along the optical axis: a first lens having negative refractive power, wherein the object side surface of the first lens is concave at the near optical axis, and the image side surface of the first lens is convex at the near optical axis; a second lens having positive refractive power, wherein the object side surface of the second lens is convex at the near optical axis, and the image side surface of the second lens is convex at the near optical axis; a third lens having positive refractive power, wherein the object side surface of the third lens is convex at the near optical axis, and the image side surface of the third lens is convex at the near optical axis; a fourth lens having negative refractive power, wherein the object side surface of the fourth lens is concave at the near optical axis, and the image side surface of the fourth lens is concave at the near optical axis; a fifth lens having positive refractive power, wherein the object side surface of the fifth lens is convex at the near optical axis, and the image side surface of the fifth lens is convex at the near optical axis; and a sixth lens having negative refractive power, wherein the object side surface of the sixth lens is concave at the near optical axis.

[0007] The optical system satisfies the relationship: 32deg≤FOV≤45deg, 2≤TTL / F≤2.71; wherein FOV is the maximum field angle of the optical system, TTL is the distance from the object side surface of the first lens to the imaging surface on the optical axis, and F is the effective focal length of the optical system.

[0008] By making the first lens have negative refractive power, and the object side surface of the first lens is concave at the near optical axis, and the image side surface of the first lens is convex at the near optical axis, it is beneficial for the smooth injection of light, so that the light will not be bent too much, effectively reducing the field curvature and astigmatism of the optical system, and reducing the overall sensitivity of the optical system; by making the second lens have positive refractive power, and the object side surface of the second lens is convex at the near optical axis, and the image side surface of the second lens is convex at the near optical axis, it is beneficial to preliminarily correct the astigmatism of the optical system, and effectively control the trend of light to achieve a larger aperture; by making the third lens have positive refractive power, and the object side surface of the third lens is convex at the near optical axis, and the image side surface of the third lens is convex at the near optical axis, it is beneficial to enhance the positive refractive power of the third lens, and further provide a reasonable light incident angle for the introduction of edge light; by making the fourth lens have negative refractive power, and the object side surface of the fourth lens is concave at the near optical axis, and the image side surface of the fourth lens is The concave surface at the near optical axis is conducive to the entry and deflection of marginal light, and can reduce the deflection angle borne by the rear lens, so that the deflection angle of light on each lens is more uniform, and the aberration of the marginal field of view is effectively corrected; the third lens and the fourth lens are cemented lenses, which are conducive to correcting chromatic aberration and balancing various aberrations, improving the resolution ability of the optical system, and can effectively reduce the tolerance sensitivity and improve the imaging quality of the optical system; by making the fifth lens have positive refractive power, and the object side surface of the fifth lens is convex at the near optical axis, and the image side surface of the fifth lens is convex at the near optical axis, it is conducive to effectively collecting and compressing the incident light on the object side of the fifth lens, so that the light smoothly transitions to the optical system on the image side of the fifth lens; by making the sixth lens have negative refractive power, and the object side surface of the sixth lens is concave at the near optical axis, it is conducive to lowering the incident angle of light after passing through the aperture, so that more light enters the optical system on the image side, and the illumination of the optical system is improved.

[0009] By making the optical system satisfy the relationship: 32deg≤FOV≤45deg, the maximum field of view of the optical system is controlled within a reasonable range, which can avoid introducing excessive aberrations and help the optical system to obtain sufficient field of view while meeting the characteristics of miniaturization.

[0010] By making the optical system satisfy the relationship: 2≤TTL / F≤2.71, the ratio of the total length of the optical system to the effective focal length is reasonably configured, which is conducive to limiting the total length of the optical system and realizing the miniaturization of the optical system.

[0011] In one implementation, the optical system satisfies the relationship: 5.9≤TTL / IMGH≤7.9; wherein IMGH is half of the image height corresponding to the maximum field angle of the optical system. By making the optical system satisfy the above relationship, the ratio of the total length of the optical system to the image height is reasonably configured, and the range of the maximum field angle of the optical system is matched, which is conducive to limiting the total length of the optical system and realizing the miniaturization of the optical system.

[0012] In one embodiment, the optical system satisfies the relationship: 20deg≤FOV / FNO≤27deg; wherein FNO is the aperture number of the optical system. By making the optical system satisfy the above relationship, the ratio of the field angle and the aperture number of the optical system is reasonably configured, and the optical system has a combination effect of a large field angle and a large aperture. The optical system has a reasonable amount of light input, which can improve the problem of a relatively fast decrease in relative brightness of the edge field of view, improve the overall illumination of the imaging picture, and also facilitate obtaining more scene information.

[0013] In one embodiment, the optical system satisfies the relationship: 2.6≤F / IMGH≤3.4; wherein F is the effective focal length of the optical system. By making the optical system satisfy the above relationship, the ratio of the effective focal length and image height of the optical system is reasonably configured, which is conducive to improving the imaging quality of the optical system.

[0014] In one embodiment, the optical system satisfies the relationship: 0.59≤∑CT / TTL≤0.66; wherein ∑CT is the sum of the thicknesses of the first lens to the sixth lens on the optical axis. By making the optical system satisfy the above relationship, the ratio of the sum of the thicknesses of the first lens to the sixth lens on the optical axis to the image height of the optical system is reasonably configured, which is conducive to compressing the total length and volume of the optical system and realizing the miniaturization of the optical system.

[0015] In one embodiment, the optical system satisfies the relationship: 6≤TTL / CTMAX≤7.4; wherein CTMAX is the maximum value of the thickness of the first lens to the sixth lens on the optical axis. By making the optical system satisfy the above relationship, the ratio of the image height of the optical system to the maximum value of the thickness of the first lens to the sixth lens on the optical axis is reasonably configured. It can be understood that the first lens to the sixth lens have a certain thickness on the optical axis, and CTMAX is the maximum value of the thickness among the six lenses, so that the ratio of the total length of the optical system to the maximum value of the thickness of the first lens to the sixth lens on the optical axis is reasonably configured, which is conducive to the reasonable setting of the thickness of each lens in the optical system, and the thickness of each lens in the optical system and the spacing distance between two adjacent lenses can be adjusted with each other, reducing the aberration and tolerance sensitivity of the optical system, and improving the imaging quality of the optical system.

[0016] In one embodiment, the optical system satisfies the relationship: 2≤∑CT / ∑AT≤2.95; wherein ∑AT is the sum of the distances between two adjacent lenses on the optical axis. By making the optical system satisfy the above relationship, the ratio of the sum of the thicknesses of the first lens to the sixth lens on the optical axis to the sum of the distances between two adjacent lenses on the optical axis is reasonably configured, so that the thickness of each lens in the optical system and the distance between two adjacent lenses are reasonably set, thereby realizing the miniaturization of the optical system and improving the processability of the optical system. It is also beneficial to mutually adjust the thickness of each lens in the optical system and the distance between two adjacent lenses, thereby reducing the aberration and tolerance sensitivity of the optical system and improving the imaging quality of the optical system.

[0017] In one embodiment, the optical system satisfies the relationship: 1.02≤SD3 / SD2≤1.16; wherein SD3 is half of the maximum effective aperture of the object side of the second lens, and SD2 is half of the maximum effective aperture of the image side of the first lens. By making the optical system satisfy the above relationship, the ratio of half of the maximum effective aperture of the object side of the second lens to half of the maximum effective aperture of the image side of the first lens is reasonably configured, and the size transition from the first lens to the second lens is smoother, which is conducive to reducing the aberration of the optical system and ensuring the imaging quality.

[0018] In one embodiment, the optical system satisfies the relationship: 1.05≤SD1 / SD12≤1.35; wherein SD1 is half of the maximum effective aperture of the object side of the first lens, and SD12 is half of the maximum effective aperture of the image side of the sixth lens. By making the optical system satisfy the above relationship, the ratio of half of the maximum effective aperture of the object side of the first lens to half of the maximum effective aperture of the image side of the sixth lens is reasonably configured, which is conducive to reasonably limiting the front port diameter and the rear port diameter of the optical system, and realizing the miniaturization of the optical system.

[0019] In one embodiment, the optical system satisfies the relationship: 1.05≤SD3 / CT2≤1.45; wherein CT2 is the thickness of the second lens on the optical axis. By making the optical system satisfy the above relationship, the ratio of half of the maximum effective aperture of the object side of the second lens and the thickness of the second lens on the optical axis is reasonably configured, which is conducive to the second lens having a suitable aperture to realize the miniaturization of the optical system, and makes the thickness ratio of the second lens more reasonable, simplifying the production of the second lens.

[0020] In one embodiment, the optical system satisfies the relationship: -2.2≤F1 / F≤-1.3; wherein F1 is the effective focal length of the first lens. By making the optical system satisfy the above relationship, the ratio of the effective focal length of the first lens to the effective focal length of the optical system is reasonably configured, which is conducive to diverging light. Under the same field of view, the light emitted from the image side of the first lens can enable the subsequent optical system to have a larger light receiving surface, thereby reducing the front port diameter of the optical system.

[0021] In one embodiment, the optical system satisfies the relationship: 0.85≤F2 / F≤1.2; wherein F2 is the effective focal length of the second lens. By making the optical system satisfy the above relationship, the ratio of the effective focal length of the second lens to the effective focal length of the optical system is reasonably configured, which is beneficial for the second lens to converge light and reduce the rear port diameter of the optical system subsequent to the second lens. The second lens is matched with the first lens with negative refractive power, which is also beneficial for reducing the total length of the optical system and realizing the miniaturization of the optical system.

[0022] In one embodiment, the optical system satisfies the relationship: 0.65≤F3 / F≤0.7; wherein F3 is the effective focal length of the third lens. By making the optical system satisfy the above relationship, the ratio of the effective focal length of the third lens to the effective focal length of the optical system is reasonably configured, which is conducive to the third lens having a suitable positive focal power, effectively optimizing spherical aberration, and achieving high-quality imaging of the optical system.

[0023] In one embodiment, the optical system satisfies the relationship: 0.22≤BFL / F≤0.3; wherein BFL is the distance from the image side surface of the sixth lens to the imaging surface on the optical axis. By making the optical system satisfy the above relationship, the ratio of the distance from the image side surface of the sixth lens to the imaging surface on the optical axis to the effective focal length of the optical system is reasonably configured, which is conducive to the reasonable setting of the optical back focus of the optical system, and the light can be more smoothly transferred to the imaging surface, thereby improving the resolution capability of the optical system.

[0024] In one embodiment, the optical system satisfies the relationship: -1.5≤F1 / F12≤-0.8; wherein F12 is the combined effective focal length of the first lens and the second lens. By making the optical system satisfy the above relationship, the ratio of the effective focal length of the first lens to the combined effective focal length of the first lens and the second lens is reasonably configured, which is conducive to balancing the distribution of the refractive power between the first lens and the second lens, so that the aberrations generated by the first lens and the second lens are mutually corrected, thereby improving the imaging quality of the optical system.

[0025] In one embodiment, the optical system satisfies the relationship: -2.5≤F5 / F4≤-1.8; wherein F5 is the effective focal length of the fifth lens, and F4 is the effective focal length of the fourth lens. By making the optical system satisfy the above relationship, the ratio of the effective focal length of the fifth lens to the effective focal length of the fourth lens is reasonably configured, which is conducive to balancing the distribution of the refractive power between the fourth lens and the fifth lens, so that the aberrations generated by the fourth lens and the fifth lens are mutually corrected, thereby improving the imaging quality of the optical system.

[0026] In one embodiment, the optical system satisfies the relationship: 0.25≤SAG3 / CT2≤0.4; wherein SAG3 is the sagittal height at the maximum effective aperture of the object side surface of the second lens, that is, the distance from the intersection of the object side surface of the second lens and the optical axis to the maximum effective aperture of the object side surface of the second lens in the direction parallel to the optical axis, and CT2 is the thickness of the second lens on the optical axis. By making the optical system satisfy the above relationship, the ratio of the sagittal height at the maximum effective aperture of the object side surface of the second lens and the thickness of the second lens on the optical axis is reasonably configured, which is conducive to reasonably controlling the refractive power and thickness of the second lens at various locations in the direction perpendicular to the optical axis, avoiding the second lens from being too thick or too thin, reducing the incident angle of light on the object side surface of the second lens, and reducing the tolerance sensitivity of the optical system.

[0027] In one embodiment, the optical system satisfies the relationship: 0.65≤CT4 / CT3≤1.4; wherein CT4 is the thickness of the fourth lens on the optical axis, and CT3 is the thickness of the third lens on the optical axis. By making the optical system satisfy the above relationship, the ratio of the thickness of the fourth lens on the optical axis to the thickness of the third lens on the optical axis is reasonably configured, and the third lens and the fourth lens can be mutually regulated to maintain the miniaturization feature of the optical system.

[0028] In one embodiment, the optical system satisfies the relationship: 0.9≤AT23 / CT3≤1.45; wherein AT23 is the distance from the image side surface of the second lens to the object side surface of the third lens on the optical axis. By making the optical system satisfy the above relationship, the ratio of the spacing distance between the second lens and the third lens to the thickness of the third lens on the optical axis is reasonably configured, which is conducive to regulating the positional relationship between the second lens and the third lens, so that the spacing distance between the second lens and the third lens is reasonably set, the processability of the optical system is improved, and the spacing distance is used to reduce the sensitivity of aberrations and tolerances.

[0029] In one embodiment, the optical system satisfies the relationship: 3.2≤F5 / CT5≤8.1; wherein CT5 is the thickness of the fifth lens on the optical axis. By making the optical system satisfy the above relationship, the ratio of the effective focal length of the fifth lens and the thickness of the fifth lens on the optical axis is reasonably configured, which is conducive to simplifying the surface setting of the fifth lens.

[0030] In one embodiment, the optical system satisfies the relationship: -20≤F6 / CT6≤-12; wherein F6 is the effective focal length of the sixth lens, and CT6 is the thickness of the sixth lens on the optical axis. By making the optical system satisfy the above relationship, the ratio of the effective focal length of the sixth lens to the thickness of the sixth lens on the optical axis is reasonably configured, which is conducive to simplifying the surface setting of the sixth lens.

[0031] In one implementation, the optical system satisfies the relationship: 25≤180°×TTL / IMGH / FOV≤40. By making the optical system satisfy the above relationship, the total length, image height and field angle of the optical system are balanced with each other, which is conducive to the optical system to achieve a balance between miniaturization, telephoto and large image surface, and improve the imaging quality of the optical system.

[0032] In one embodiment, the optical system satisfies the relationship: -1.5≤R5 / R6≤-1.1; wherein R5 is the radius of curvature of the object side of the third lens at the optical axis, and R6 is the radius of curvature of the image side of the third lens at the optical axis. By making the optical system satisfy the above relationship, it is beneficial to reasonably configure the ratio of the radius of curvature of the object side of the third lens at the optical axis to the radius of curvature of the image side 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 resolution of the optical system, and at the same time, it is also beneficial to reduce the difficulty of processing the third lens.

[0033] In one embodiment, the optical system satisfies the relationship: -1.2≤R7 / R8≤-0.8; wherein R7 is the radius of curvature of the object side of the fourth lens at the optical axis, and R8 is the radius of curvature of the image side of the fourth lens at the optical axis. By making the optical system satisfy the above relationship, it is beneficial to reasonably configure the ratio of the radius of curvature of the object side of the fourth lens at the optical axis to the radius of curvature of the image side 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 resolution of the optical system, and at the same time, it is also beneficial to reduce the difficulty of processing the fourth lens.

[0034] In the second aspect, the present invention further provides a camera module, which includes a photosensitive chip and the optical system described in any one of the embodiments of the first aspect, wherein the photosensitive chip is arranged 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 the light of the object incident on the photosensitive surface through the lens can be converted into an electrical signal of the 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 in an electronic device, or it can be an independent lens. By adding the optical system provided by the present invention to the camera module, the surface shape and refractive power of each lens in the optical system can be reasonably designed, so that the camera module has the characteristics of miniaturization, high pixel and large field of view.

[0035] In a third aspect, the present invention further provides an electronic device, the electronic device comprising a housing and the camera module described in the second aspect, the camera module being disposed in the housing. The electronic device includes but is not limited to automobiles, monitoring equipment, smart phones, computers, and smart watches. By adding the camera module provided by the present invention to the electronic device, the electronic device has the characteristics of miniaturization, high pixel and large field of view. BRIEF DESCRIPTION OF THE DRAWINGS

[0036] In order to more clearly illustrate the embodiments of the present invention or the technical solutions in the prior art, the drawings required for use in the embodiments or the description of the prior art will be briefly introduced below. Obviously, the drawings described below are only some embodiments of the present invention. For ordinary technicians in this field, other drawings can be obtained based on these drawings without paying creative work.

[0037] Figure 1 is a schematic structural diagram of the optical system of the first embodiment; Figure 2 A longitudinal spherical aberration curve diagram, an astigmatism curve diagram and a distortion curve diagram of the optical system of the first embodiment are shown; Figure 3 is a schematic structural diagram of an optical system of a second embodiment; Figure 4 A longitudinal spherical aberration curve diagram, an astigmatism curve diagram and a distortion curve diagram of the optical system of the second embodiment are shown; Figure 5 is a schematic structural diagram of an optical system of a third embodiment; Figure 6 A longitudinal spherical aberration curve diagram, an astigmatism curve diagram and a distortion curve diagram of the optical system of the third embodiment are shown; Figure 7 is a schematic structural diagram of an optical system of a fourth embodiment; Figure 8 A longitudinal spherical aberration curve diagram, an astigmatism curve diagram and a distortion curve diagram of the optical system of the fourth embodiment are shown; Fig. 9 is a schematic structural diagram of an optical system of a fifth embodiment; Fig.10 A longitudinal spherical aberration curve diagram, an astigmatism curve diagram and a distortion curve diagram of the optical system of the fifth embodiment are shown; Fig.11 A schematic structural diagram of a camera module in one embodiment of the present invention is shown; Fig.12 A schematic structural diagram of an electronic device in an embodiment of the present invention is shown. DETAILED DESCRIPTION

[0038] The following will be combined with the drawings in the embodiments of the present invention to clearly and completely describe the technical solutions in the embodiments of the present invention. Obviously, the described embodiments are only part of the embodiments of the present invention, not all of the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by ordinary technicians in this field without creative work are within the scope of protection of the present invention.

[0039] In a first aspect, the present invention provides an optical system, which has a total of six lenses with refractive power, which include, in order from the object side to the image side along the optical axis: a first lens, which has negative refractive power, the object side surface of the first lens is concave at the near optical axis, and the image side surface of the first lens is convex at the near optical axis; a second lens, which has positive refractive power, the object side surface of the second lens is convex at the near optical axis, and the image side surface of the second lens is convex at the near optical axis; a third lens, which has positive refractive power, the object side surface of the third lens is convex at the near optical axis The fourth lens has negative refractive power, the object side surface of the fourth lens is concave at the near optical axis, and the image side surface of the fourth lens is concave at the near optical axis; the fifth lens has positive refractive power, the object side surface of the fifth lens is convex at the near optical axis, and the image side surface of the fifth lens is convex at the near optical axis; the sixth lens has negative refractive power, the object side surface of the sixth lens is concave at the near optical axis, and the image side surface of the sixth lens can be convex, concave or flat at the near optical axis.

[0040] The optical system satisfies the relationship: 32deg≤FOV≤45deg, 2≤TTL / F≤2.71; wherein FOV is the maximum field of view of the optical system, TTL is the distance from the object side of the first lens to the imaging plane on the optical axis, and F is the effective focal length of the optical system. Specifically, the value of FOV can be 34deg, 40deg, 44deg, 38deg, 32deg, 45deg, 36deg, 41deg, 43deg, etc. Specifically, the value of TTL / F can be 2.252, 2.704, 2.609, 2.013, 2.348, 2.051, 2.457, 2.502, etc.

[0041] By making the first lens have negative refractive power, and the object side surface of the first lens is concave at the near optical axis, and the image side surface of the first lens is convex at the near optical axis, it is beneficial to the smooth injection of light, so that the light will not be bent too much, effectively reducing the field curvature and astigmatism of the optical system, and reducing the overall sensitivity of the optical system; by making the second lens have positive refractive power, and the object side surface of the second lens is convex at the near optical axis, and the image side surface of the second lens is convex at the near optical axis, it is beneficial to preliminarily correct the astigmatism of the optical system, and effectively control the trend of light to achieve a larger aperture; by making the third lens have positive refractive power, and the object side surface of the third lens is convex at the near optical axis, and the image side surface of the third lens is convex at the near optical axis, it is beneficial to enhance the positive refractive power of the third lens, and further provide a reasonable light incident angle for the introduction of marginal light; by making the fourth lens have negative refractive power, and the object side surface of the fourth lens is concave at the near optical axis, and the image side surface of the fourth lens is concave at the near optical axis, it is beneficial to The entry and deflection of marginal light can reduce the deflection angle borne by the rear lens, so that the deflection angle of light on each lens is more uniform, and the aberration of the marginal field of view is effectively corrected; the third lens and the fourth lens are cemented lenses, which are conducive to correcting chromatic aberration and balancing various aberrations, improving the resolution of the optical system, and can effectively reduce the tolerance sensitivity and improve the imaging quality of the optical system; by making the fifth lens have positive refractive power, and the object side surface of the fifth lens is convex at the near optical axis, and the image side surface of the fifth lens is convex at the near optical axis, it is conducive to effectively collecting and compressing the incident light on the object side of the fifth lens, so that the light smoothly transitions to the optical system on the image side of the fifth lens; by making the sixth lens have negative refractive power, and the object side surface of the sixth lens is concave at the near optical axis, and the image side surface of the sixth lens is convex, concave or flat at the near optical axis, it is conducive to lowering the incident angle of light after the light passes through the aperture, so that more light enters the optical system on the image side, and the illumination of the optical system is improved.

[0042] By making the optical system satisfy the relationship: 32deg≤FOV≤45deg, the maximum field of view of the optical system is controlled within a reasonable range, which can avoid introducing excessive aberrations and help the optical system to obtain sufficient field of view while meeting the characteristics of miniaturization.

[0043] By making the optical system satisfy the relationship: 2≤TTL / F≤2.71, the ratio of the total length of the optical system to the effective focal length is reasonably configured, which is conducive to limiting the total length of the optical system and realizing the miniaturization of the optical system.

[0044] In one implementation, the optical system satisfies the relationship: 5.9≤TTL / IMGH≤7.9; wherein IMGH is half of the image height corresponding to the maximum field angle of the optical system. Specifically, the value of TTL / IMGH can be 7.511, 7.872, 6.831, 5.976, 7.045, 5.903, 6.381, 6.517, etc. By making the optical system satisfy the above relationship, the ratio of the total length and image height of the optical system is reasonably configured, and the range of the maximum field angle of the optical system is matched, which is conducive to limiting the total length of the optical system and realizing the miniaturization of the optical system.

[0045] In one embodiment, the optical system satisfies the relationship: 20deg≤FOV / FNO≤27deg; wherein FNO is the aperture number of the optical system. Specifically, the value of FOV / FNO can be 20.600deg, 23.984deg, 26.190deg, 23.043deg, 22.611deg, 20.323deg, 26.945deg, 24.336deg, etc. By making the optical system satisfy the above relationship, the ratio of the field of view angle and the aperture number of the optical system is reasonably configured, and the optical system has a combination effect of a large field of view angle and a large aperture. The optical system has a reasonable amount of light input, which can improve the problem of a rapid decrease in relative brightness of the edge field of view, improve the overall illumination of the imaging picture, and also facilitate obtaining more scene information.

[0046] In one implementation, the optical system satisfies the relationship: 2.6≤F / IMGH≤3.4; wherein F is the effective focal length of the optical system. Specifically, the value of F / IMGH may be 3.336, 2.912, 2.618, 2.969, 3.001, 2.723, 2.863, 3.295, etc. By making the optical system satisfy the above relationship, the ratio of the effective focal length and image height of the optical system is reasonably configured, which is beneficial to improving the imaging quality of the optical system.

[0047] In one embodiment, the optical system satisfies the relationship: 0.59≤∑CT / TTL≤0.66; wherein ∑CT is the sum of the thicknesses of the first lens to the sixth lens on the optical axis. Specifically, the value of ∑CT / TTL can be 0.601, 0.597, 0.652, 0.616, 0.636, 0.642, 0.591, 0.604, etc. By making the optical system satisfy the above relationship, the ratio of the sum of the thicknesses of the first lens to the sixth lens on the optical axis to the image height of the optical system is reasonably configured, which is conducive to compressing the total length and volume of the optical system and realizing the miniaturization of the optical system.

[0048] In one embodiment, the optical system satisfies the relationship: 6≤TTL / CTMAX≤7.4; wherein CTMAX is the maximum value of the thickness of the first lens to the sixth lens on the optical axis. Specifically, the value of TTL / CTMAX can be 7.023, 7.386, 6.544, 6.508, 6.113, 6.062, 6.362, 6.812, etc. By making the optical system satisfy the above relationship, the ratio of the image height of the optical system to the maximum value of the thickness of the first lens to the sixth lens on the optical axis is reasonably configured. It can be understood that the first lens to the sixth lens have a certain thickness on the optical axis, and CTMAX is the maximum value of the thickness among the six lenses, so that the ratio of the total length of the optical system to the maximum value of the thickness of the first lens to the sixth lens on the optical axis is reasonably configured, which is conducive to the reasonable setting of the thickness of each lens in the optical system, and the thickness of each lens in the optical system and the spacing distance between two adjacent lenses can be adjusted with each other, reducing the aberration and tolerance sensitivity of the optical system, and improving the imaging quality of the optical system.

[0049] In one embodiment, the optical system satisfies the relationship: 2≤∑CT / ∑AT≤2.95; wherein ∑AT is the sum of the distances between two adjacent lenses on the optical axis. Specifically, the value of ∑CT / ∑AT can be 2.019, 2.005, 2.026, 2.922, 2.257, 2.652, 2.463, 2.877, etc. By making the optical system satisfy the above relationship, the ratio of the sum of the thickness of the first lens to the sixth lens on the optical axis to the sum of the distances between two adjacent lenses on the optical axis is reasonably configured, so that the thickness of each lens in the optical system and the distance between two adjacent lenses are reasonably set, the miniaturization of the optical system is achieved, and the processability of the optical system is improved. It is also beneficial to adjust the thickness of each lens in the optical system and the distance between two adjacent lenses, reduce the aberration and tolerance sensitivity of the optical system, and improve the imaging quality of the optical system.

[0050] In one embodiment, the optical system satisfies the relationship: 1.02≤SD3 / SD2≤1.16; wherein SD3 is half of the maximum effective aperture of the object side of the second lens, and SD2 is half of the maximum effective aperture of the image side of the first lens. Specifically, the value of SD3 / SD2 can be 1.093, 1.150, 1.040, 1.072, 1.109, 1.036, 1.069, 1.027, etc. By making the optical system satisfy the above relationship, the ratio of half of the maximum effective aperture of the object side of the second lens to half of the maximum effective aperture of the image side of the first lens is reasonably configured, and the size transition from the first lens to the second lens is smoother, which is conducive to reducing the aberration of the optical system and ensuring the imaging quality.

[0051] In one embodiment, the optical system satisfies the relationship: 1.05≤SD1 / SD12≤1.35; wherein SD1 is half of the maximum effective aperture of the object side of the first lens, and SD12 is half of the maximum effective aperture of the image side of the sixth lens. Specifically, the value of SD1 / SD12 can be 1.319, 1.169, 1.314, 1.091, 1.300, 1.056, 1.223, 1.274, etc. By making the optical system satisfy the above relationship, the ratio of half of the maximum effective aperture of the object side of the first lens to half of the maximum effective aperture of the image side of the sixth lens is reasonably configured, which is conducive to reasonably limiting the front port diameter and the rear port diameter of the optical system, and realizing the miniaturization of the optical system.

[0052] In one embodiment, the optical system satisfies the relationship: 1.05≤SD3 / CT2≤1.45; wherein CT2 is the thickness of the second lens on the optical axis. Specifically, the value of SD3 / CT2 can be 1.443, 1.188, 1.118, 1.349, 1.094, 1.061, 1.211, 1.287, etc. By making the optical system satisfy the above relationship, the ratio of half of the maximum effective aperture of the object side of the second lens and the thickness of the second lens on the optical axis is reasonably configured, which is conducive to the second lens having a suitable aperture to realize the miniaturization of the optical system, and makes the thickness ratio of the second lens more reasonable, simplifying the production of the second lens.

[0053] In one embodiment, the optical system satisfies the relationship: -2.2≤F1 / F≤-1.3; wherein F1 is the effective focal length of the first lens. Specifically, the value of F1 / F can be -2.158, -1.660, -2.062, -1.368, -1.824, -1.462, -1.728, -1.905, etc. By making the optical system satisfy the above relationship, the ratio of the effective focal length of the first lens to the effective focal length of the optical system is reasonably configured, which is conducive to diverging light. Under the same field of view angle, the light emitted from the image side of the first lens can enable the subsequent optical system to have a larger light receiving surface, thereby reducing the front port diameter of the optical system.

[0054] In one embodiment, the optical system satisfies the relationship: 0.85≤F2 / F≤1.2; wherein F2 is the effective focal length of the second lens. Specifically, the value of F2 / F can be 1.068, 1.150, 1.159, 0.873, 1.069, 0.859, 0.935, 0.998, etc. By making the optical system satisfy the above relationship, the ratio of the effective focal length of the second lens to the effective focal length of the optical system is reasonably configured, which is beneficial for the second lens to converge light and reduce the rear port diameter of the optical system subsequent to the second lens. The second lens is matched with the first lens with negative refractive power, which is also beneficial to reduce the total length of the optical system and realize the miniaturization of the optical system.

[0055] In one embodiment, the optical system satisfies the relationship: 0.65≤F3 / F≤0.7; wherein F3 is the effective focal length of the third lens. Specifically, the value of F3 / F can be 0.690, 0.686, 0.651, 0.682, 0.655, 0.661, 0.672, 0.678, etc. By making the optical system satisfy the above relationship, the ratio of the effective focal length of the third lens to the effective focal length of the optical system is reasonably configured, which is conducive to the third lens having a suitable positive focal power, effectively optimizing spherical aberration, and achieving high-quality imaging of the optical system.

[0056] In one embodiment, the optical system satisfies the relationship: 0.22≤BFL / F≤0.3; wherein BFL is the distance from the image side surface of the sixth lens to the imaging surface on the optical axis. Specifically, the value of BFL / F can be 0.229, 0.270, 0.284, 0.252, 0.260, 0.221, 0.297, 0.264, etc. By making the optical system satisfy the above relationship, the ratio of the distance from the image side surface of the sixth lens to the imaging surface on the optical axis and the effective focal length of the optical system is reasonably configured, which is conducive to the reasonable setting of the optical back focus of the optical system, and the light can be more smoothly transitioned to the imaging surface, thereby improving the resolution capability of the optical system.

[0057] In one embodiment, the optical system satisfies the relationship: -1.5≤F1 / F12≤-0.8; wherein F12 is the combined effective focal length of the first lens and the second lens. Specifically, the value of F1 / F12 can be -1.452, -0.930, -1.326, -0.892, -1.146, -0.823, -1.034, -1.288, etc. By making the optical system satisfy the above relationship, the ratio of the effective focal length of the first lens to the combined effective focal length of the first lens and the second lens is reasonably configured, which is conducive to balancing the refractive power distribution between the first lens and the second lens, so that the aberrations generated by the first lens and the second lens are mutually corrected, thereby improving the imaging quality of the optical system.

[0058] In one embodiment, the optical system satisfies the relationship: -2.5≤F5 / F4≤-1.8; wherein F5 is the effective focal length of the fifth lens, and F4 is the effective focal length of the fourth lens. Specifically, the value of F5 / F4 can be -1.886, -1.909, -2.473, -2.046, -2.495, -1.835, -2.111, -2.234, etc. By making the optical system satisfy the above relationship, the ratio of the effective focal length of the fifth lens to the effective focal length of the fourth lens is reasonably configured, which is conducive to balancing the refractive power distribution between the fourth lens and the fifth lens, so that the aberrations generated by the fourth lens and the fifth lens are mutually corrected, thereby improving the imaging quality of the optical system.

[0059] In one embodiment, the optical system satisfies the relationship: 0.25≤SAG3 / CT2≤0.4; wherein SAG3 is the sagittal height at the maximum effective aperture of the object side surface of the second lens, that is, the distance from the intersection of the object side surface of the second lens and the optical axis to the maximum effective aperture of the object side surface of the second lens in the direction parallel to the optical axis, and CT2 is the thickness of the second lens on the optical axis. Specifically, the value of SAG3 / CT2 can be 0.393, 0.284, 0.345, 0.275, 0.315, 0.253, 0.302, 0.373, etc. By making the optical system satisfy the above relationship, the ratio of the sagittal height at the maximum effective aperture of the object side surface of the second lens and the thickness of the second lens on the optical axis is reasonably configured, which is conducive to reasonably controlling the refractive power and thickness of the second lens at various locations perpendicular to the optical axis, avoiding the second lens from being too thick or too thin, reducing the incident angle of light on the object side surface of the second lens, and reducing the tolerance sensitivity of the optical system.

[0060] In one embodiment, the optical system satisfies the relationship: 0.65≤CT4 / CT3≤1.4; wherein CT4 is the thickness of the fourth lens on the optical axis, and CT3 is the thickness of the third lens on the optical axis. Specifically, the value of CT4 / CT3 can be 1.048, 0.877, 0.693, 1.328, 0.826, 0.655, 0.997, 1.281, etc. By making the optical system satisfy the above relationship, the ratio of the thickness of the fourth lens on the optical axis to the thickness of the third lens on the optical axis is reasonably configured, and the third lens and the fourth lens can be mutually regulated to maintain the miniaturization feature of the optical system.

[0061] In one embodiment, the optical system satisfies the relationship: 0.9≤AT23 / CT3≤1.45; wherein AT23 is the distance from the image side surface of the second lens to the object side surface of the third lens on the optical axis. Specifically, the value of AT23 / CT3 can be 1.408, 1.224, 0.912, 1.356, 1.136, 0.955, 1.044, 1.223, etc. By making the optical system satisfy the above relationship, the ratio of the spacing distance between the second lens and the third lens to the thickness of the third lens on the optical axis is reasonably configured, which is conducive to regulating the positional relationship between the second lens and the third lens, so that the spacing distance between the second lens and the third lens is reasonably set, improving the processability of the optical system, and using the spacing distance to reduce aberration and tolerance sensitivity.

[0062] In one embodiment, the optical system satisfies the relationship: 3.2≤F5 / CT5≤8.1; wherein CT5 is the thickness of the fifth lens on the optical axis. Specifically, the value of F5 / CT5 can be 3.237, 8.068, 6.115, 7.306, 5.920, 4.721, 5.333, 6.821, etc. By making the optical system satisfy the above relationship, the ratio of the effective focal length of the fifth lens and the thickness of the fifth lens on the optical axis is reasonably configured, which is conducive to simplifying the surface setting of the fifth lens.

[0063] In one embodiment, the optical system satisfies the relationship: -20≤F6 / CT6≤-12; wherein F6 is the effective focal length of the sixth lens, and CT6 is the thickness of the sixth lens on the optical axis. Specifically, the value of F6 / CT6 can be -18.368, -12.236, -17.176, -12.986, -17.894, -14.521, -19.631, -15.823, etc. By making the optical system satisfy the above relationship, the ratio of the effective focal length of the sixth lens and the thickness of the sixth lens on the optical axis is reasonably configured, which is conducive to simplifying the surface setting of the sixth lens.

[0064] In one implementation, the optical system satisfies the relationship: 25≤180°×TTL / IMGH / FOV≤40. Specifically, the value of 180°×TTL / IMGH / FOV may be 39.765, 35.426, 27.946, 28.305, 33.372, 25.182, 30.233, 26.731, etc. By making the optical system satisfy the above relationship, the total length, image height and field angle of the optical system are balanced with each other, which is beneficial for the optical system to achieve a balance between miniaturization, telephoto and large image plane, and improve the imaging quality of the optical system.

[0065] In one embodiment, the optical system satisfies the relationship: -1.5≤R5 / R6≤-1.1; wherein R5 is the radius of curvature of the object side of the third lens at the optical axis, and R6 is the radius of curvature of the image side of the third lens at the optical axis. Specifically, the value of R5 / R6 can be -1.400, -1.390, -1.435, -1.194, -1.113, -1.214, -1.300, -1.498, etc. By making the optical system satisfy the above relationship, it is beneficial to reasonably configure the ratio of the radius of curvature of the object side of the third lens at the optical axis and the radius of curvature of the image side 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 resolution of the optical system, and at the same time, it is also beneficial to reduce the processing difficulty of the third lens.

[0066] In one embodiment, the optical system satisfies the relationship: -1.2≤R7 / R8≤-0.8; wherein R7 is the radius of curvature of the object side of the fourth lens at the optical axis, and R8 is the radius of curvature of the image side of the fourth lens at the optical axis. Specifically, the value of R7 / R8 can be -1.066, -0.928, -0.869, -1.050, -1.128, -0.805, -0.984, -1.176, etc. By making the optical system satisfy the above relationship, it is beneficial to reasonably configure the ratio of the radius of curvature of the object side of the fourth lens at the optical axis and the radius of curvature of the image side 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 resolution of the optical system, and at the same time, it is also beneficial to reduce the processing difficulty of the fourth lens.

[0067] In one embodiment, the optical system satisfies the relationship: 1.64≤FNO≤1.7; wherein R3 is the radius of curvature of the object side of the second lens, and R4 is the radius of curvature of the image side of the second lens. Specifically, the value of FNO can be 1.650, 1.668, 1.680, 1.649, 1.681, 1.696, 1.657, 1.673, etc. By making the optical system satisfy the above relationship, it is beneficial to 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, and improve the resolution of the optical system.

[0068] In one embodiment, the optical system satisfies the relationship: -0.6≤F4 / F≤-0.54. Specifically, the value of F4 / F can be -0.550, -0.564, -0.563, -0.583, -0.557, -0.547, -0.592, -0.574, etc. By making the optical system satisfy the above relationship, it is beneficial for the refractive power of the fourth lens in the optical system to be properly coordinated, the surface design of the fourth lens is simpler and more flexible, the aberration is reduced, and the balance between the aberration correction and the imaging quality of the overall optical system is simplified.

[0069] In one embodiment, the optical system satisfies the relationship: 1≤F5 / F≤1.4; wherein F5 is the effective focal length of the fifth lens. Specifically, the value of F5 / F can be 1.038, 1.078, 1.393, 1.193, 1.390, 1.225, 1.343, 1.279, etc. By making the optical system satisfy the above relationship, it is beneficial for the refractive power of the fifth lens in the optical system to be properly coordinated, the surface design of the fifth lens is simpler and more flexible, the aberration is reduced, and the balance between the aberration correction and the imaging quality of the overall optical system is simplified.

[0070] In one embodiment, the optical system satisfies the relationship: -1.2≤F6 / F≤-0.85; wherein F6 is the effective focal length of the sixth lens. Specifically, the value of F6 / F can be -0.919, -1.022, -1.139, -0.882, -1.123, -0.853, -0.962, -1.185, etc. By making the optical system satisfy the above relationship, it is beneficial for the refractive power of the sixth lens in the optical system to be properly coordinated, the surface design of the sixth lens is simpler and more flexible, the aberration is reduced, and the balance between the aberration correction and the imaging quality of the overall optical system is simplified.

[0071] In one embodiment, the optical system satisfies the relationship: 0.1≤R1 / R2≤0.35; wherein R1 is the radius of curvature of the object side of the first lens at the optical axis, and R2 is the radius of curvature of the image side of the first lens at the optical axis. Specifically, the value of R1 / R2 can be 0.323, 0.129, 0.197, 0.215, 0.198, 0.266, 0.281, 0.348, etc. By making the optical system satisfy the above relationship, it is beneficial to reasonably configure the ratio of the radius of curvature of the object side of the first lens at the optical axis to the radius of curvature of the image side 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 resolution of the optical system, and at the same time, it is also beneficial to reduce the processing difficulty of the first lens.

[0072] In one embodiment, the optical system satisfies the relationship: -0.8≤R3 / R4≤-0.15; wherein R3 is the radius of curvature of the object side of the second lens at the optical axis, and R4 is the radius of curvature of the image side of the second lens at the optical axis. Specifically, the value of R3 / R4 can be -0.352, -0.453, -0.177, -0.795, -0.283, -0.507, -0.636, -0.711, etc. By making the optical system satisfy the above relationship, it is beneficial to reasonably configure the ratio of the radius of curvature of the object side of the second lens at the optical axis to the radius of curvature of the image side 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 resolution of the optical system, and at the same time, it is also beneficial to reduce the processing difficulty of the second lens.

[0073] In one embodiment, the optical system satisfies the relationship: -0.7≤R9 / R10≤-0.35; wherein R9 is the radius of curvature of the object side of the fifth lens at the optical axis, and R10 is the radius of curvature of the image side of the fifth lens at the optical axis. Specifically, the value of R9 / R10 can be -0.557, -0.453, -0.679, -0.619, -0.385, -0.357, -0.406, -0.582, etc. By making the optical system satisfy the above relationship, it is beneficial to reasonably configure the ratio of the radius of curvature of the object side of the fifth lens at the optical axis and the radius of curvature of the image side 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 resolution of the optical system, and at the same time, it is also beneficial to reduce the processing difficulty of the fifth lens.

[0074] In one embodiment, the optical system satisfies the relationship: |R11 / R12|≤0.2; wherein R11 is the radius of curvature of the object side of the sixth lens at the optical axis, and R12 is the radius of curvature of the image side of the sixth lens at the optical axis. Specifically, the value of |R11 / R12| can be 0.029, 0.192, 0.146, 0.019, 0.190, 0.047, 0.086, 0.163, etc. By making the optical system satisfy the above relationship, it is beneficial to reasonably configure the ratio of the radius of curvature of the object side of the sixth lens at the optical axis to the radius of curvature of the image side 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 resolution of the optical system, and at the same time, it is also beneficial to reduce the processing difficulty of the sixth lens.

[0075] In one implementation, the optical system satisfies the relationship: 0.4≤CT6 / ET6≤0.52. Specifically, the value of CT6 / ET6 can be 0.411, 0.505, 0.444, 0.460, 0.485, 0.423, 0.479, 0.518, etc. By making the optical system satisfy the above relationship, the ratio of the thickness of the sixth lens on the optical axis to the edge thickness of the sixth lens is reasonably configured, which is conducive to simplifying the production and manufacturing of the sixth lens.

[0076] In some embodiments, the optical system further includes a filter, which may be an infrared cutoff filter, an infrared bandpass filter or a double-pass filter. In the present application, the filter is an infrared cutoff filter, which is used to filter out infrared light and only allow visible light to pass through, so that the imaging is more in line with the visual experience of the human eye. Of course, the filter may also be an infrared bandpass filter, which is fixedly arranged relative to each lens in the optical system. The infrared bandpass filter is used to pass infrared light of the central wavelength, has the function of filtering out background stray light, and is used for infrared lenses. In addition, the filter may also be a double-pass filter, which can simultaneously transmit visible light and partially transmit infrared light, thereby achieving different band selections, which can realize both visible light imaging and infrared imaging, thereby achieving universal use during day and night. The filter can be assembled together with each lens as part of the optical system. In other embodiments, the filter may also be an independent component outside the optical system. The filter can be installed between the optical system and the photosensitive chip when the optical system and the photosensitive chip are assembled. It is understandable that the filter can be made of optical glass coating, or can be made of colored glass, or a filter of other materials, which can be selected according to actual needs and is not specifically limited in this embodiment. In other embodiments, a filter coating can be provided on at least one of the first lens to the fifth lens to achieve the filtering effect.

[0077] In some embodiments, at least one lens in the optical system may have a spherical surface type. The design of the spherical surface type can reduce the difficulty of preparing the lens and reduce the preparation cost. In some embodiments, at least one lens of the optical system may also have an aspherical surface type. When at least one side surface of the lens (object side or image side) is aspherical, the lens can be said to have an aspherical surface type. In some embodiments, the object side and image side of each lens can also be designed as aspherical surfaces. The aspherical design can help the optical system eliminate aberrations more effectively and improve the imaging quality. In some embodiments, in order to take into account the preparation cost, preparation difficulty, imaging quality, assembly difficulty, etc., the design of each lens surface in the optical system can be composed of a combination of spherical and aspherical surface types. In the present application, the second lens has an aspherical surface type, and the first lens, the third lens, the fourth lens, the fifth lens and the sixth lens have a spherical surface type.

[0078] 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. The thermal drift effect of the glass material of the first lens L1 can effectively reduce the impact of ambient temperature changes on the optical system, thereby maintaining better and more stable imaging quality. In some embodiments, at least one lens in the optical system can also be made of plastic (PC), and the plastic material can be polycarbonate, gum, etc. Lenses made of plastic can reduce the production cost of the optical system, while lenses made of glass can withstand higher or lower temperatures and have excellent optical effects and better stability. In some embodiments, lenses of different materials can be set in the optical system, that is, a design combining glass lenses and plastic lenses can be adopted, but the specific configuration relationship can be determined according to actual needs, and is not exhaustively listed here.

[0079] First embodiment Please refer to Figure 1 The optical system 10 of this embodiment includes, in order from the object side to the image side along the optical axis direction: The first lens L1 has negative refractive power. The object-side surface S1 of the first lens L1 is concave at the near optical axis, and the image-side surface S2 is convex at the near optical axis.

[0080] The second lens L2 has positive refractive power. The object-side surface S3 of the second lens L2 is convex at the near optical axis, and the image-side surface S4 is convex at the near optical axis.

[0081] The third lens L3 has positive refractive power. The object-side surface S5 of the third lens L3 is convex at the near optical axis, and the image-side surface S6 is convex at the near optical axis.

[0082] The fourth lens L4 has negative refractive power. The object-side surface S7 of the fourth lens L4 is concave at the near optical axis, and the image-side surface S8 is concave at the near optical axis.

[0083] The fifth lens element L5 has positive refractive power. The object-side surface S9 of the fifth lens element L5 is convex at the near optical axis, and the image-side surface S10 is convex at the near optical axis.

[0084] The sixth lens L6 has negative refractive power. The object-side surface S11 of the sixth lens L6 is concave at the near optical axis, and the image-side surface S12 is concave at the near optical axis.

[0085] In addition, the optical system 10 further includes an aperture STO, a filter IR, a protective glass CG and an imaging surface IMG. In this embodiment, the aperture STO is arranged between the image side surface of the first lens L1 and the object side surface of the second lens L2 of the optical system 10, and is used to control the amount of light entering. The filter IR is arranged between the sixth lens L6 and the protective glass CG, and includes an object side surface S13 and an image side surface S14. The filter IR is an infrared cut-off filter, and the infrared cut-off filter is used to filter out infrared light, so that the light incident on the imaging surface IMG is visible light, and the wavelength of visible light is 380nm-780nm. The material of the infrared cut-off filter can be glass (Glass) or plastic (Plastic), and a film can be coated on its surface. The protective glass CG is arranged between the filter IR and the imaging surface IMG, and includes an object side surface S15 and an image side surface S16. The material of the first lens L1 to the sixth lens L6 can be glass (Glass) or plastic (Plastic). The effective pixel area of ​​the photosensitive chip is located on the imaging surface. An infrared photosensitive chip is arranged at the imaging surface IMG. The photosensitive chip captures different band information of the object for subsequent processing.

[0086] Table 1a shows the various parameters of the optical system 10 of this embodiment, wherein the Y radius is the radius of curvature of the object side or image side of the corresponding surface number at the optical axis. Surface number S1 and surface number 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 a smaller surface number is the object side surface, and the surface with a 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, 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. The focal length, material refractive index and Abbe number are all obtained using visible light with a reference wavelength of 555nm, and the units of the Y radius, thickness and effective focal length are all millimeters (mm); Table 1a

[0087] 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 angle of the optical system 10, and TTL is the distance from the object side of the first lens to the imaging plane on the optical axis, that is, the total optical length.

[0088] In this embodiment, both the object-side surface and the image-side surface of the second lens L2 are aspherical surfaces, and the surface shape x of the aspherical surface can be defined by but not limited to the following aspherical surface formula:

[0089] Among them, x is the distance from the corresponding point on the aspherical surface to the plane tangent to the surface vertex, h is the distance from the corresponding point on the aspherical surface to the optical axis, c is the curvature of the aspherical vertex, k is the cone coefficient, and Ai is the coefficient corresponding to the i-th high-order term in the aspherical surface shape formula.

[0090] Table 1b gives the high-order coefficients A4, A6, A8, A10, A12, A14 and A16 that can be used for the aspherical mirror surfaces S3 and S4 in the first embodiment; Table 1b

[0091] Figure 2 (a) shows the longitudinal spherical aberration curve of the optical system 10 of the first embodiment at wavelengths of 680.0000nm, 650.0000nm, 610.0000nm, 555.0000nm, 510.0000nm, 470.0000nm, and 430.0000nm, wherein the abscissa along the X-axis direction represents the focus offset, i.e., the distance from the imaging plane to the intersection of the light and the optical axis (in mm), and the ordinate along the Y-axis direction represents the normalized field of view. The longitudinal spherical aberration curve represents the deviation of the convergent focus of light of different wavelengths after passing through each lens of the optical system 10. Figure 2 As can be seen in (a), the degree of deviation of the convergence focus of the light of each wavelength in the first embodiment tends to be consistent, and the dispersion spots or color halo in the imaging picture are effectively suppressed by the optical system 10, indicating that the imaging quality of the optical system 10 in this embodiment is good.

[0092] Figure 2 (b) also shows the astigmatism curve of the optical system 10 of the first embodiment at a wavelength of 555.0000nm, where the horizontal axis along the X-axis direction represents the focus offset, and the vertical axis along the Y-axis direction represents the field angle, with the unit of deg. The S curve in the astigmatism curve represents the sagittal field curvature at 555.0000nm, and the T curve represents the meridian field curvature at 555.0000nm. Figure 2 As can be seen in (b), the field curvature of the optical system 10 is small, the field curvature and astigmatism of each field of view are well corrected, and clear images are obtained at the center and edge of the field of view.

[0093] Figure 2(c) also shows the distortion curve of the optical system 10 of the first embodiment when the wavelength is 555.0000nm. The horizontal axis along the X-axis direction represents the distortion value, the unit is %, and the vertical axis along the Y-axis direction represents the field of view angle, the unit is deg. The distortion curve represents the distortion value corresponding to different field of view angles. Figure 2 It can be seen in (c) that at a wavelength of 555.0000nm, the image deformation caused by the main beam is small and the imaging quality of the system is excellent.

[0094] Depend on Figure 2 Middle (a), Figure 2 (b) and Figure 2 It can be seen from (c) that the optical system 10 of this embodiment has small aberration, good imaging quality and excellent imaging quality.

[0095] Second embodiment Please refer to Figure 3 The optical system 10 of this embodiment includes, in order from the object side to the image side along the optical axis direction: The first lens L1 has negative refractive power. The object-side surface S1 of the first lens L1 is concave at the near optical axis, and the image-side surface S2 is convex at the near optical axis.

[0096] The second lens L2 has positive refractive power. The object-side surface S3 of the second lens L2 is convex at the near optical axis, and the image-side surface S4 is convex at the near optical axis.

[0097] The third lens L3 has positive refractive power. The object-side surface S5 of the third lens L3 is convex at the near optical axis, and the image-side surface S6 is convex at the near optical axis.

[0098] The fourth lens L4 has negative refractive power. The object-side surface S7 of the fourth lens L4 is concave at the near optical axis, and the image-side surface S8 is concave at the near optical axis.

[0099] The fifth lens element L5 has positive refractive power. The object-side surface S9 of the fifth lens element L5 is convex at the near optical axis, and the image-side surface S10 is convex at the near optical axis.

[0100] The sixth lens L6 has negative refractive power. The object-side surface S11 of the sixth lens L6 is concave at the near optical axis, and the image-side surface S12 is concave at the near optical axis.

[0101] The other structures of the second embodiment are the same as those of the first embodiment, and can be used as a reference.

[0102] Table 2a shows various parameters of the optical system 10 of this embodiment, wherein the focal length, material refractive index and Abbe number are all obtained by using visible light with a reference wavelength of 555 nm, the units of the Y radius, thickness and effective focal length are all millimeters (mm), and the meanings of other parameters are the same as those of the first embodiment; Table 2a

[0103] Table 2b gives the coefficients of the higher order terms that can be used for each aspherical mirror surface in the second embodiment, wherein each aspherical surface type can be defined by the formula given in the first embodiment; Table 2b

[0104] Figure 4 Middle (a), Figure 4 Middle (b), Figure 4 (c) shows the longitudinal spherical aberration curve, astigmatism curve and distortion curve of the optical system 10 of the second embodiment, wherein the longitudinal spherical aberration curve indicates the deviation of the convergence focus of light of different wavelengths after passing through each lens of the optical system 10; the astigmatism curve indicates the meridian field curvature and sagittal field curvature; and the distortion curve indicates the distortion magnitude value corresponding to different field angles. Figure 4 As can be seen from the aberration diagram in , the longitudinal spherical aberration, field curvature and distortion of the optical system 10 are all well controlled, so that the optical system 10 of this embodiment has good imaging quality.

[0105] Third embodiment Please refer to Figure 5 The optical system 10 of this embodiment includes, in order from the object side to the image side along the optical axis direction: The first lens L1 has negative refractive power. The object-side surface S1 of the first lens L1 is concave at the near optical axis, and the image-side surface S2 is convex at the near optical axis.

[0106] The second lens L2 has positive refractive power. The object-side surface S3 of the second lens L2 is convex at the near optical axis, and the image-side surface S4 is convex at the near optical axis.

[0107] The third lens L3 has positive refractive power. The object-side surface S5 of the third lens L3 is convex at the near optical axis, and the image-side surface S6 is convex at the near optical axis.

[0108] The fourth lens L4 has negative refractive power. The object-side surface S7 of the fourth lens L4 is concave at the near optical axis, and the image-side surface S8 is concave at the near optical axis.

[0109] The fifth lens element L5 has positive refractive power. The object-side surface S9 of the fifth lens element L5 is convex at the near optical axis, and the image-side surface S10 is convex at the near optical axis.

[0110] The sixth lens L6 has negative refractive power. The object-side surface S11 of the sixth lens L6 is concave at the near optical axis, and the image-side surface S12 is convex at the near optical axis.

[0111] The other structures of the third embodiment are the same as those of the first embodiment, and can be used as a reference.

[0112] Table 3a shows various parameters of the optical system 10 of this embodiment, wherein the focal length, material refractive index and Abbe number are all obtained by using visible light with a reference wavelength of 555 nm, the units of the Y radius, thickness and effective focal length are all millimeters (mm), and the meanings of other parameters are the same as those of the first embodiment; Table 3a

[0113] Table 3b gives the coefficients of the higher order terms that can be used for each aspherical mirror surface in the third embodiment, wherein each aspherical surface type can be defined by the formula given in the first embodiment; Table 3b

[0114] Figure 6 Middle (a), Figure 6 Middle (b), Figure 6 (c) shows the longitudinal spherical aberration curve, astigmatism curve and distortion curve of the optical system 10 of the third embodiment, wherein the longitudinal spherical aberration curve indicates the deviation of the convergence focus of light of different wavelengths after passing through each lens of the optical system 10; the astigmatism curve indicates the meridian field curvature and sagittal field curvature; and the distortion curve indicates the distortion magnitude value corresponding to different field angles. Figure 6 As can be seen from the aberration diagram in , the longitudinal spherical aberration, field curvature and distortion of the optical system 10 are all well controlled, so that the optical system 10 of this embodiment has good imaging quality.

[0115] Fourth embodiment Please refer to Figure 7 The optical system 10 of this embodiment includes, in order from the object side to the image side along the optical axis direction: The first lens L1 has negative refractive power. The object-side surface S1 of the first lens L1 is concave at the near optical axis, and the image-side surface S2 is convex at the near optical axis.

[0116] The second lens L2 has positive refractive power. The object-side surface S3 of the second lens L2 is convex at the near optical axis, and the image-side surface S4 is convex at the near optical axis.

[0117] The third lens L3 has positive refractive power. The object-side surface S5 of the third lens L3 is convex at the near optical axis, and the image-side surface S6 is convex at the near optical axis.

[0118] The fourth lens L4 has negative refractive power. The object-side surface S7 of the fourth lens L4 is concave at the near optical axis, and the image-side surface S8 is concave at the near optical axis.

[0119] The fifth lens element L5 has positive refractive power. The object-side surface S9 of the fifth lens element L5 is convex at the near optical axis, and the image-side surface S10 is convex at the near optical axis.

[0120] The sixth lens L6 has negative refractive power. The object-side surface S11 of the sixth lens L6 is concave at the near optical axis, and the image-side surface S12 is convex at the near optical axis.

[0121] The other structures of the fourth embodiment are the same as those of the first embodiment, and can be referred to herein.

[0122] Table 4a shows various parameters of the optical system 10 of this embodiment, wherein the focal length, material refractive index and Abbe number are all obtained by using visible light with a reference wavelength of 555 nm, the units of the Y radius, thickness and effective focal length are all millimeters (mm), and the meanings of other parameters are the same as those of the first embodiment; Table 4a

[0123] Table 4b gives the coefficients of the higher-order terms that can be used for each aspherical mirror surface in the fourth embodiment, wherein each aspherical surface type can be defined by the formula given in the first embodiment; Table 4b

[0124] Figure 8 Middle (a), Figure 8 Middle (b), Figure 8 (c) shows the longitudinal spherical aberration curve, astigmatism curve and distortion curve of the optical system 10 of the fourth embodiment, wherein the longitudinal spherical aberration curve indicates the deviation of the convergence focus of light of different wavelengths after passing through each lens of the optical system 10; the astigmatism curve indicates the meridian field curvature and sagittal field curvature; and the distortion curve indicates the distortion magnitude value corresponding to different field angles. Figure 8 As can be seen from the aberration diagram in , the longitudinal spherical aberration, field curvature and distortion of the optical system 10 are all well controlled, so that the optical system 10 of this embodiment has good imaging quality.

[0125] Fifth embodiment Please refer to Fig. 9 The optical system 10 of this embodiment includes, in order from the object side to the image side along the optical axis direction: The first lens L1 has negative refractive power. The object-side surface S1 of the first lens L1 is concave at the near optical axis, and the image-side surface S2 is convex at the near optical axis.

[0126] The second lens L2 has positive refractive power. The object-side surface S3 of the second lens L2 is convex at the near optical axis, and the image-side surface S4 is convex at the near optical axis.

[0127] The third lens L3 has positive refractive power. The object-side surface S5 of the third lens L3 is convex at the near optical axis, and the image-side surface S6 is convex at the near optical axis.

[0128] The fourth lens L4 has negative refractive power. The object-side surface S7 of the fourth lens L4 is concave at the near optical axis, and the image-side surface S8 is concave at the near optical axis.

[0129] The fifth lens element L5 has positive refractive power. The object-side surface S9 of the fifth lens element L5 is convex at the near optical axis, and the image-side surface S10 is convex at the near optical axis.

[0130] The sixth lens L6 has negative refractive power. The object-side surface S11 of the sixth lens L6 is concave at the near optical axis, and the image-side surface S12 is convex at the near optical axis.

[0131] The other structures of the fifth embodiment are the same as those of the first embodiment, and can be referred to herein.

[0132] Table 5a shows various parameters of the optical system 10 of this embodiment, wherein the focal length, material refractive index and Abbe number are all obtained by using visible light with a reference wavelength of 555 nm, the units of the Y radius, thickness and effective focal length are all millimeters (mm), and the meanings of other parameters are the same as those of the first embodiment; Table 5a

[0133] Table 5b gives the coefficients of the higher order terms that can be used for each aspherical mirror surface in the fifth embodiment, wherein each aspherical surface type can be defined by the formula given in the first embodiment; Table 5b

[0134] Fig.10 Middle (a), Fig.10 Middle (b), Fig.10 (c) shows the longitudinal spherical aberration curve, astigmatism curve and distortion curve of the optical system 10 of the fifth embodiment, wherein the longitudinal spherical aberration curve indicates the deviation of the convergence focus of light of different wavelengths after passing through each lens of the optical system 10; the astigmatism curve indicates the meridian field curvature and sagittal field curvature; and the distortion curve indicates the distortion magnitude value corresponding to different field angles. Fig.10 As can be seen from the aberration diagram in , the longitudinal spherical aberration, field curvature and distortion of the optical system 10 are all well controlled, so that the optical system 10 of this embodiment has good imaging quality.

[0135] Table 6 shows the values ​​of FOV, TTL / F, TTL / IMGH, FOV / FNO, F / IMGH, ∑CT / TTL, TTL / CTMAX, ∑CT / ∑AT, SD3 / SD2, SD1 / SD12, SD3 / CT2, F1 / F, F2 / F, F3 / F, BFL / F, F1 / F12, F5 / F4, SAG3 / CT2, CT4 / CT3, AT23 / CT3, F5 / CT5, F6 / CT6, 180°×TTL / IMGH / FOV, R5 / R6, R7 / R8, FNO, F4 / F, F5 / F, F6 / F, R1 / R2, R3 / R4, R9 / R10, |R11 / R12|, and CT6 / ET6 in the optical system 10 of the first to fifth embodiments; Table 6

[0136] It can be seen from Table 6 that the optical systems of the first embodiment to the fifth embodiment all satisfy the following relationship: 32deg≤FOV≤45deg, 2≤TTL / F≤2.71, 5.9≤TTL / IMGH≤7.9, 20deg≤FOV / FNO≤27deg, 2.6≤F / IMGH≤3.4, 0.59≤∑CT / TTL≤0.66, 6≤TTL / CTMAX≤7.4, 2≤∑CT / ∑AT≤2.95, 1.02≤SD3 / SD2≤1 .16、1.05≤SD1 / SD12≤1.35、1.05≤SD3 / CT2≤1.45、-2.2≤F1 / F≤-1.3、0.85≤F2 / F≤1.2、0.65≤F3 / F≤0.7、0.22≤BFL / F≤0.3、-1.5≤F1 / F12≤-0.8、-2.5≤F5 / F4≤-1.8、0.25≤SAG3 / CT2≤0.4、0.65≤CT4 / CT3≤1.4、0.9≤AT23 / CT3≤1.45, 3.2≤F5 / CT5≤8.1, -20≤F6 / CT6≤-12, 25≤180°×TTL / IMGH / FOV≤40, -1.5≤R5 / R6≤-1.1, -1.2≤R7 / R8≤-0.8, 1.64≤FNO≤1.7, -0.6≤F4 / F≤-0.54, 1≤F5 / F≤1.4, -1.2≤F6 / F≤-0.85, 0.1≤R1 / R2≤0.35, -0.8≤R3 / R4≤-0.15, -0.7≤R9 / R10≤-0.35, |R11 / R12|≤0.2 and 0.4≤CT6 / ET6≤0.52.

[0137] See also Fig.11The present invention also provides a camera module 20, which includes a photosensitive chip 21 and the optical system 10 described in any one of the above embodiments, wherein the photosensitive chip 21 is arranged 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 the light of the object incident on the photosensitive surface through the lens can be converted into an electrical signal of the 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 on the electronic device 30, or it can be an independent lens. By adding the optical system 10 provided by the present invention to the camera module 20, the surface shape and refractive power of each lens in the optical system 10 can be reasonably designed, so that the camera module 20 has the characteristics of miniaturization, high pixel and large field of view.

[0138] See also Fig.12 The present invention further provides an electronic device 30, which includes a housing 31 and the camera module 20, wherein the camera module 20 is disposed in the housing 31. The electronic device 30 includes, but is not limited to, automobiles, monitoring equipment, smart phones, computers, and smart watches. By adding the camera module 20 provided by the present invention to the electronic device 30, the electronic device 30 has the characteristics of miniaturization, high pixel and large field of view.

[0139] The above disclosures are only some preferred embodiments of the present invention, which certainly cannot be used to limit the scope of the present invention. Ordinary technicians in this field can understand that all or part of the processes of the above embodiments and equivalent changes made according to the claims of the present invention are still within the scope of the present invention.

Claims

1. An optical system, characterized in that: There are six lenses with refractive power, including: A first lens having negative refractive power, wherein the object side surface of the first lens is concave at the near optical axis, and the image side surface of the first lens is convex at the near optical axis; A second lens having positive refractive power, an object side surface of the second lens being convex at the near optical axis, and an image side surface of the second lens being convex at the near optical axis; A third lens having positive refractive power, wherein the object side surface of the third lens is convex at the near optical axis, and the image side surface of the third lens is convex at the near optical axis; a fourth lens having negative refractive power, wherein the object side surface of the fourth lens is concave at the near optical axis, and the image side surface of the fourth lens is concave at the near optical axis; a fifth lens having positive refractive power, wherein the object side surface of the fifth lens is convex at the near optical axis, and the image side surface of the fifth lens is convex at the near optical axis; a sixth lens element having negative refractive power, wherein the object side surface of the sixth lens element is concave at a position close to the optical axis; The optical system satisfies the relationship: 32deg≤FOV≤45deg, 2≤TTL / F≤2.71; Wherein, FOV is the maximum field of view of the optical system, TTL is the distance from the object side of the first lens to the imaging plane on the optical axis, and F is the effective focal length of the optical system.

2. The optical system according to claim 1, wherein: The optical system satisfies the relationship: 5.9≤TTL / IMGH≤7.9; 20deg≤FOV / FNO≤27deg; and / or, 2.6≤F / IMGH≤3.4; Wherein, IMGH is half of the image height corresponding to the maximum field angle of the optical system, and FNO is the aperture number of the optical system.

3. The optical system according to claim 1, wherein: The optical system satisfies the relationship: 0.59≤∑CT / TTL≤0.66; and / or, 6 ≤ TTL / CTMAX ≤ 7.4; and / or, 2≤∑CT / ∑AT≤2.95; Wherein, ∑CT is the sum of thicknesses of the first lens to the sixth lens on the optical axis, CTMAX is the maximum value of thicknesses of the first lens to the sixth lens on the optical axis, and ∑AT is the sum of interval distances between two adjacent lenses on the optical axis.

4. The optical system according to claim 1, wherein: The optical system satisfies the relationship: 1.02≤SD3 / SD2≤1.16; and / or, 1.05≤SD1 / SD12≤1.35; and / or, 1.05≤SD3 / CT2≤1.45; Among them, SD3 is half of the maximum effective aperture of the object side of the second lens, SD2 is half of the maximum effective aperture of the image side of the first lens, SD1 is half of the maximum effective aperture of the object side of the first lens, SD12 is half of the maximum effective aperture of the image side of the sixth lens, and CT2 is the thickness of the second lens on the optical axis.

5. The optical system according to claim 1, wherein: The optical system satisfies the relationship: -2.2≤F1 / F≤-1.3; and / or, 0.85≤F2 / F≤1.2; and / or, 0.65≤F3 / F≤0.7; and / or, 0.22≤BFL / F≤0.3; Among them, F1 is the effective focal length of the first lens, F2 is the effective focal length of the second lens, F3 is the effective focal length of the third lens, and BFL is the distance from the image side surface of the sixth lens to the imaging surface on the optical axis.

6. The optical system according to claim 1, wherein: The optical system satisfies the relationship: -1.5≤F1 / F12≤-0.8; and / or, -2.5≤F5 / F4≤-1.8; and / or, 0.25≤SAG3 / CT2≤0.4; Among them, F1 is the effective focal length of the first lens, F12 is the combined effective focal length of the first lens and the second lens, F5 is the effective focal length of the fifth lens, F4 is the effective focal length of the fourth lens, SAG3 is the sag at the maximum effective aperture of the object side of the second lens, and CT2 is the thickness of the second lens on the optical axis.

7. The optical system according to claim 1, wherein: The optical system satisfies the relationship: 0.65≤CT4 / CT3≤1.4; and / or, 0.9≤AT23 / CT3≤1.45; and / or, 3.2≤F5 / CT5≤8.1; and / or, -20≤F6 / CT6≤-12; Among them, CT4 is the thickness of the fourth lens on the optical axis, CT3 is the thickness of the third lens on the optical axis, AT23 is the distance from the image side surface of the second lens to the object side surface of the third lens on the optical axis, F5 is the effective focal length of the fifth lens, CT5 is the thickness of the fifth lens on the optical axis, F6 is the effective focal length of the sixth lens, and CT6 is the thickness of the sixth lens on the optical axis.

8. The optical system according to claim 1, wherein: The optical system satisfies the relationship: 25≤180°×TTL / IMGH / FOV≤40; and / or, -1.5≤R5 / R6≤-1.1; and / or, -1.2≤R7 / R8≤-0.8; Among them, IMGH is half of the image height corresponding to the maximum field angle of the optical system, R5 is the curvature radius of the object side of the third lens at the optical axis, R6 is the curvature radius of the image side of the third lens at the optical axis, R7 is the curvature radius of the object side of the fourth lens at the optical axis, and R8 is the curvature radius of the image side of the fourth lens at the optical axis.

9. A camera module, characterized in that: The optical system comprises a photosensitive chip and 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: The electronic device includes a housing and the camera module according to claim 9, and the camera module is arranged in the housing.

Images