Optical system, camera module and electronic device

Abstract

An optical system, a camera module and an electronic device, the optical system includes five lenses with refractive power, and the optical system sequentially includes, from the object side to the image side along the optical axis, a first lens with refractive power, a second lens, a third lens, a fourth lens with positive refractive power, and a fifth lens with negative refractive power; the object side and the image side of the first lens, the image side of the third lens, the object side and the image side of the fourth lens, and the image side of the fifth lens are all concave near the optical axis, and the object side and the image side of the fourth lens are both convex near the optical axis, and through reasonable design of the lenses of the optical system, the optical system can meet a large field of view, miniaturization and good imaging effect.

Description

Technical Field

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

[0002] In recent years, portable electronic products with a photography function have shown a trend of becoming thinner and lighter. Therefore, the demand for an optical system to meet high imaging quality and miniaturization is also increasing, such as a larger field of view angle. However, being able to meet the imaging requirements in different environments usually means a more complex structure of the optical system, which ultimately leads to an increase in the size and total length of the camera module and is difficult to be applied to thin and light electronic products.

[0003] Therefore, how to achieve miniaturization and good imaging effects while ensuring that the optical system has a large field of view angle has become one of the problems that must be solved in the industry. Summary of the Invention

[0004] The purpose of the present invention is to provide an optical system, a camera module, and an electronic device to meet the requirements of a large field of view angle, miniaturization, and good imaging effects of the optical system.

[0005] To achieve the purpose of the present invention, the following technical solutions are provided:

[0006] In a first aspect, the present invention provides an optical system, which includes a total of five lenses with refractive power, and successively includes from the object side to the image side along the optical axis: a first lens with refractive power, the object side and the image side of the first lens are concave surfaces near the optical axis; a second lens with refractive power; a third lens with refractive power, the image side of the third lens is a concave surface near the optical axis; a fourth lens with positive refractive power, the object side and the image side of the fourth lens are convex surfaces near the optical axis; a fifth lens with negative refractive power, the image side of the fifth lens is a concave surface near the optical axis.

[0007] The optical system satisfies the relational expression: 120deg < FOV < 140deg; where FOV is the maximum field of view angle of the optical system.

[0008] By making the first lens have refractive power and both the object side and the image side of the first lens be concave near the optical axis, it is beneficial to increase the incident angle of light and expand the view angle of the optical system. At the same time, it is also beneficial to reasonably control the size of the effective aperture of the first lens to meet the requirement of miniaturization of the optical system. By making the second lens have refractive power, it is beneficial to correct the spherical aberration, coma and distortion generated by the first lens, thereby improving the imaging quality of the optical system. By making the third lens have refractive power and the image side of the third lens be concave near the optical axis, it is beneficial for marginal rays to enter and be refracted, which can reduce the deflection angle borne by the subsequent lenses, making the deflection angles of light on each lens more uniform and effectively correcting the aberration of the marginal field of view. By making the fourth lens have positive refractive power and both the object side and the image side of the fourth lens be convex near the optical axis, it is beneficial to converge the incident light, reduce the aberration of marginal rays, and at the same time reduce the risk of ghost images generated by the optical system. By making the fifth lens have negative refractive power and the image side of the fifth lens be concave near the optical axis, it is beneficial to correct the aberration of the optical system, reasonably distribute the refractive power of the optical system, improve the compactness between lenses, and achieve the characteristics of miniaturization.

[0009] By making the optical system satisfy the relation: 120deg < FOV < 140deg, it is beneficial to control the maximum view angle of the optical system within a reasonable range, effectively increase the view area of the picture, and make the optical system have a large view angle.

[0010] In one implementation, the optical system satisfies the relation: 1.35 < f / T12 < 1.95; where f is the effective focal length of the optical system, and T12 is the distance on the optical axis from the image side of the first lens to the object side of the second lens. By making the optical system satisfy the above relation, it is beneficial to reasonably configure the ratio of the effective focal length of the optical system to the distance on the optical axis from the image side of the first lens to the object side of the second lens, effectively control the relationship between the focal length of the optical system and the interval distance between the first lens and the second lens. On the basis of ensuring that the optical system has sufficient refractive ability for light, it guarantees good thin and light characteristics. At the same time, it makes the interval distance between the first lens and the second lens sufficient, reduces the sensitivity of the optical system, reduces axial chromatic aberration, and avoids the interval distance between the lenses in the optical system being too close, which affects the normal assembly of the optical system.

[0011] In one embodiment, the optical system satisfies the relationship: -6.55 < f3 / f2 < 1.25; where f3 is the effective focal length of the third lens and f2 is the effective focal length of the second lens. By making the optical system satisfy the above relationship, it is beneficial to reasonably configure the ratio of the effective focal length of the third lens to the effective focal length of the second lens, further balance the refractive power distribution between the lenses, so that the aberrations generated by the second lens and the third lens are corrected with each other, and the aberration generated by the first lens is corrected, strengthening the aberration correction of the optical system, thereby improving the imaging quality of the optical system. At the same time, it is also beneficial to size compression, making the optical system miniaturized and enabling the optical system to have a sufficient imaging range.

[0012] In one embodiment, the optical system satisfies the relationship: 0.35 < CT5 / CT4 < 0.55; where CT5 is the thickness of the fifth lens on the optical axis and CT4 is the thickness of the fourth lens on the optical axis. By making the optical system satisfy the above relationship, it is beneficial to reasonably control the central thickness of the fourth lens, thereby effectively avoiding the problem of difficult processing technology caused by the fourth lens being too thin, controlling the ratio of the thickness of the fifth lens on the optical axis to the thickness of the fourth lens on the optical axis within a reasonable range, and also beneficial to reducing the size of the optical system and maintaining its miniaturized characteristics.

[0013] In one embodiment, the optical system satisfies the relationship: 1.15 < CT2 / CT3 < 1.75; where CT2 is the thickness of the second 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, it is beneficial to reasonably configure the ratio of the thickness of the second lens on the optical axis to the thickness of the third lens on the optical axis, reasonably control the central thickness of the third lens, thereby effectively avoiding the problem of difficult processing technology caused by the third lens being too thin, reducing the size of the optical system and maintaining its miniaturized characteristics. At the same time, it is also beneficial to reduce the sensitivity of the optical system.

[0014] In one embodiment, the optical system satisfies the relationship: 1.82 < CT4 / CT1 < 2.7; where CT4 is the thickness of the fourth lens on the optical axis and CT1 is the thickness of the first lens on the optical axis. By making the optical system satisfy the above relationship, it is beneficial to control the ratio of the thickness of the fourth lens on the optical axis to the thickness of the first lens on the optical axis within a reasonable range, effectively reducing the size of the optical system and maintaining its miniaturized characteristics. At the same time, it is also beneficial to avoid the imbalance of the spatial configuration of each lens in the optical system, thereby improving the imaging quality of the optical system.

[0015] In one embodiment, the optical system satisfies the relationship: 0.8 < (R51 + R52) / (R51 - R52) < 1.6; where R51 is the radius of curvature of the object side surface of the fifth lens on the optical axis, and R52 is the radius of curvature of the image side surface of the fifth lens on the optical axis. By making the optical system satisfy the above relationship, it is beneficial to reasonably control the radii of curvature of the object side surface and the image side surface of the fifth lens, thereby effectively controlling the shape of the fifth lens, shortening the total length of the optical system, maintaining its miniaturized characteristics. At the same time, the fifth lens refracts the incident light more gently, avoiding an increase in aberration, and is also beneficial for correcting the aberrations of the first lens to the fourth lens, improving the imaging effect of the optical system.

[0016] In one embodiment, the optical system satisfies the relationship: 3.5 < |R51| / f < 166; where R51 is the radius of curvature of the object side surface of the fifth lens on the optical axis, and f is the effective focal length of the optical system. 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 surface of the fifth lens on the optical axis to the effective focal length of the optical system, effectively controlling the bending degree of the object side surface of the fifth lens, optimizing the refractive power of the fifth lens, reducing the sensitivity of the optical system, and improving the imaging quality of the optical system.

[0017] In one embodiment, the optical system further includes an aperture, and the aperture is located between the first lens and the second lens. The optical system satisfies the relationship: 0.72 ≤ SL / TTL < 0.78; where SL is the distance from the aperture to the imaging surface of the optical system on the optical axis, and TTL is the distance from the object side surface of the first lens to the imaging surface of the optical system on the optical axis. By making the optical system satisfy the above relationship, it is beneficial to reasonably set the aperture in the optical system, increase the aperture of the aperture, thereby effectively controlling the incident angle of the marginal field light when entering the optical system, adjusting the light input amount of the optical system, improving the relative brightness of the marginal field, and further improving the imaging quality. Below the lower limit of the relationship, the total length of the optical system is too large, which is not conducive to meeting the requirements of the optical system for being thin and light; exceeding the upper limit of the relationship, the imaging range of the object space of the optical system is too small, which is not conducive to meeting the requirements of the optical system for being wide-angle.

[0018] In one embodiment, the optical system satisfies the relationship: 2.69 < TTL / ImgH ≤ 2.8; where TTL is the distance from the object side surface of the first lens to the imaging surface of the optical system on the optical axis, and 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, it is beneficial to meet the requirements of higher imaging quality. At the same time, it is also beneficial to compress the overall length of the optical system, making the structure of the optical system more compact and meeting the requirements of the optical system for miniaturization.

[0019] In one embodiment, the optical system satisfies the relationship: 0 < AT45 / ET5 ≤ 0.1; where AT45 is the distance on the optical axis from the image side of the fourth lens to the object side of the fifth lens, and ET5 is the edge thickness of the fifth lens. By making the optical system satisfy the above relationship, it is beneficial to reasonably configure the edge thickness of the fifth lens, provide a suitable deflection angle for the marginal rays, reduce aberration. At the same time, it is also beneficial to adjust the positional relationship between the fourth lens and the fifth lens, make the spacing distance between the fourth lens and the fifth lens reasonable, improve the processability of the optical system, and use this spacing distance to reduce aberration and tolerance sensitivity.

[0020] In one embodiment, the optical system satisfies the relationship: 3 < |R41 / ET4| < 6.4; where R41 is the curvature radius of the object side of the fourth lens on the optical axis, and ET4 is the edge thickness of the fourth lens. By making the optical system satisfy the above relationship, it is beneficial to reasonably configure the ratio of the curvature radius of the object side of the fourth lens on the optical axis to the edge thickness of the fourth lens, so that the light rays converged by the first lens and the second lens gradually diverge at the fourth lens, avoiding excessive deflection angles of the light rays in the optical system and increasing the sensitivity of the optical system. When the above relationship is satisfied and ET4 < 0.51, the fourth lens is meniscus-shaped, the refractive power of the fourth lens changes, the aberration introduced by the object side of the fourth lens is small, and the aberration introduced by the image side of the fourth lens can cooperate with other lenses to correct the overall aberration of the optical system, making the refractive power of the optical system reasonably configured, and then improving the imaging quality of the optical system; when ET4 < 0.2, it is difficult to balance the thickness on the optical axis and the edge thickness of the fourth lens, increasing the manufacturing difficulty of the lens.

[0021] In one embodiment, the optical system satisfies the relationship: 0.85 < |Y52 / Y11| < 1.04; where Y52 is the maximum effective radius of the image side of the fifth lens, and Y11 is the maximum effective radius of the object side of the first lens. By making the optical system satisfy the above relationship, it is beneficial to reasonably configure the ratio of the maximum effective radius of the image side of the fifth lens to the maximum effective radius of the object side of the first lens, increase the incident angle of the light rays, expand the viewing angle of the optical system, and is also beneficial to improving the imaging quality of the optical system.

[0022] In one embodiment, the optical system satisfies the relation: 0.79 < SD11 / ImgH < 0.92; where SD11 is 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 angle of the optical system. By making the optical system satisfy the above relation, it is beneficial to control the ratio of the maximum effective aperture of the object side surface of the first lens to the image height corresponding to the maximum field angle of the optical system within a reasonable range, ensure that the effective aperture of the first lens remains within a reasonable range, make the aperture sizes of each lens appropriate, facilitate the design and manufacture of a miniaturized lens barrel, ensure the feasibility of miniaturization, and further improve the compactness of the optical system structure. At the same time, it is also beneficial to improve the refractive ability of the first lens to light, thereby reducing distortion and aberration.

[0023] In one embodiment, the optical system satisfies the relation: -0.4 < (CT2 / R21) + (CT2 / R22) < 0.65; where CT2 is the thickness of the second lens on the optical axis, R21 is the curvature radius of the object side surface of the second lens on the optical axis, and R22 is the curvature radius of the image side surface of the second lens on the optical axis. By making the optical system satisfy the above relation, it is beneficial to reasonably configure the thickness of the second lens on the optical axis and the curvature radii of the object side surface and the image side surface of the second lens, improve the manufacturing yield of the second lens. At the same time, it is also beneficial to correct aberration and improve the imaging quality of the optical system.

[0024] In a second aspect, the present invention further provides an imaging module, which includes a photosensitive chip and the optical system according to any one of the embodiments in the first aspect. The photosensitive chip is disposed on the image side of the optical system. Among them, 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 an image. The photosensitive chip can be a Complementary Metal Oxide Semiconductor (CMOS) or a Charge-coupled Device (CCD). The imaging module can be an imaging module integrated on an electronic device or an independent lens. By adding the optical system provided by the present invention to the imaging module, it is possible to reasonably design the surface shape and refractive power of each lens in the optical system, so that the imaging module satisfies a large field angle, miniaturization, and has a good imaging effect.

[0025] 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 systems, smartphones, computers, and smartwatches. By incorporating the camera module provided by the present invention into the electronic device, the device achieves a wide field of view, miniaturization, and excellent imaging performance. Attached Figure Description

[0026] 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.

[0027] Figure 1a This is a schematic diagram of the optical system of the first embodiment;

[0028] Figure 1b The diagrams showing the longitudinal spherical aberration, astigmatism, and distortion curves of the optical system of the first embodiment are illustrated.

[0029] Figure 2a This is a schematic diagram of the optical system of the second embodiment;

[0030] Figure 2b The longitudinal spherical aberration curve, astigmatism curve, and distortion curve of the optical system of the second embodiment are shown.

[0031] Figure 3a This is a schematic diagram of the optical system of the third embodiment;

[0032] Figure 3b The longitudinal spherical aberration curve, astigmatism curve, and distortion curve of the optical system of the third embodiment are shown.

[0033] Figure 4a This is a schematic diagram of the optical system of the fourth embodiment;

[0034] Figure 4b The longitudinal spherical aberration curve, astigmatism curve, and distortion curve of the optical system of the fourth embodiment are shown.

[0035] Figure 5a This is a schematic diagram of the optical system of the fifth embodiment;

[0036] Figure 5b The longitudinal spherical aberration curve, astigmatism curve, and distortion curve of the optical system of the fifth embodiment are shown.

[0037] Figure 6aIt is a schematic structural diagram of the optical system of the sixth embodiment;

[0038] Figure 6b It shows the longitudinal spherical aberration curve graph, astigmatism curve graph and distortion curve graph of the optical system of the sixth embodiment;

[0039] Figure 7 It shows a schematic structural diagram of a camera module in an embodiment of the present invention;

[0040] Figure 8 It shows a schematic structural diagram of an electronic device in an embodiment of the present invention. Specific embodiments

[0041] Next, the technical solutions in the embodiments of the present invention will be clearly and completely described in conjunction with the accompanying drawings in the embodiments of the present invention. Obviously, the described embodiments are only a part of the embodiments of the present invention, rather than all of the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by those of ordinary skill in the art without creative efforts shall fall within the protection scope of the present invention.

[0042] In the first aspect, the present invention provides an optical system, which has a total of five lenses with refractive power, and successively includes from the object side to the image side along the optical axis: a first lens with refractive power, the object side surface and the image side surface of the first lens are both concave surfaces near the optical axis; a second lens with refractive power; a third lens with refractive power, the image side surface of the third lens is a concave surface near the optical axis; a fourth lens with positive refractive power, the object side surface and the image side surface of the fourth lens are both convex surfaces near the optical axis; a fifth lens with negative refractive power, the image side surface of the fifth lens is a concave surface near the optical axis.

[0043] The optical system satisfies the relationship: 120deg < FOV < 140deg; where FOV is the maximum field angle of the optical system. Specifically, the value of FOV can be 130.34, 129.80, 132.64, 130.16, 136.00, 125.88, 127.47, 134.42, etc.

[0044] By making the first lens have refractive power and both the object side and the image side of the first lens be concave near the optical axis, it is beneficial to increase the incident angle of light and expand the field angle of the optical system. At the same time, it is also beneficial to reasonably control the size of the optical effective aperture of the first lens to meet the requirement of miniaturization of the optical system; by making the second lens have refractive power, it is beneficial to correct the spherical aberration, coma and distortion generated by the first lens, thereby improving the imaging quality of the optical system; by making the third lens have refractive power and the image side of the third lens be concave near the optical axis, it is beneficial for marginal rays to enter and be refracted, which can reduce the deflection angle borne by the subsequent lens, making the deflection angles of the rays on each lens more uniform and effectively correcting the aberration of the marginal field of view; by making the fourth lens have positive refractive power and both the object side and the image side of the fourth lens be convex near the optical axis, it is beneficial to converge the incident light, reduce the aberration of the marginal rays, and at the same time reduce the risk of ghost images generated by the optical system; by making the fifth lens have negative refractive power and the image side of the fifth lens be concave near the optical axis, it is beneficial to correct the aberration of the optical system, reasonably distribute the refractive power of the optical system, improve the compactness between the lenses, and achieve the characteristics of miniaturization.

[0045] By making the optical system satisfy the relationship: 120deg < FOV < 140deg, it is beneficial to control the maximum field angle of the optical system within a reasonable range, effectively increase the view area of the picture, and make the optical system have a large field angle.

[0046] In one implementation, the optical system satisfies the relationship: 1.35 < f / T12 < 1.95; where f is the effective focal length of the optical system, and T12 is the distance on the optical axis from the image side of the first lens to the object side of the second lens. Specifically, the value of f / T12 can be 1.921, 1.852, 1.378, 1.655, 1.821, 1.632, 1.598, 1.767, etc.

[0047] By making the optical system satisfy the above relationship, it is beneficial to reasonably configure the ratio of the effective focal length of the optical system to the distance on the optical axis from the image side of the first lens to the object side of the second lens, effectively control the relationship between the focal length of the optical system and the interval distance between the first lens and the second lens. On the basis of ensuring that the optical system has sufficient refractive ability for light, it can ensure good thin and light characteristics. At the same time, it makes the interval distance between the first lens and the second lens sufficient, reduces the sensitivity of the optical system, reduces axial chromatic aberration, and avoids the lens interval distance in the optical system being too close, which affects the normal assembly of the optical system.

[0048] In one embodiment, the optical system satisfies the relation: -6.55 < f3 / f2 < 1.25; where f3 is the effective focal length of the third lens and f2 is the effective focal length of the second lens. Specifically, the value of f3 / f2 can be -3.281, -3.559, -0.157, 1.143, -0.116, -6.516, 1.248, -4.294, etc.

[0049] By making the optical system satisfy the above relation, it is beneficial to rationally configure the ratio of the effective focal length of the third lens to the effective focal length of the second lens, further balance the refractive power distribution between the lenses, so that the aberrations generated by the second lens and the third lens are corrected with each other, and the aberration generated by the first lens is corrected, strengthening the aberration correction of the optical system, thereby improving the imaging quality of the optical system. At the same time, it is also beneficial to size compression, making the optical system miniaturized and enabling the optical system to have a sufficient imaging range.

[0050] In one embodiment, the optical system satisfies the relation: 0.35 < CT5 / CT4 < 0.55; where CT5 is the thickness of the fifth lens on the optical axis and CT4 is the thickness of the fourth lens on the optical axis. Specifically, the value of CT5 / CT4 can be 0.408, 0.400, 0.463, 0.482, 0.375, 0.520, 0.352, 0.548, etc.

[0051] By making the optical system satisfy the above relation, it is beneficial to reasonably control the central thickness of the fourth lens, thereby effectively avoiding the problem of difficult processing technology caused by the fourth lens being too thin, controlling the ratio of the thickness of the fifth lens on the optical axis to the thickness of the fourth lens on the optical axis within a reasonable range, and also beneficial to reducing the size of the optical system and maintaining its miniaturized characteristics.

[0052] In one embodiment, the optical system satisfies the relation: 1.15 < CT2 / CT3 < 1.75; where CT2 is the thickness of the second lens on the optical axis and CT3 is the thickness of the third lens on the optical axis. Specifically, the value of CT2 / CT3 can be 1.748, 1.704, 1.305, 1.300, 1.165, 1.702, 1.298, 1.467, etc.

[0053] By making the optical system satisfy the above relation, it is beneficial to rationally configure the ratio of the thickness of the second lens on the optical axis to the thickness of the third lens on the optical axis, reasonably control the central thickness of the third lens, thereby effectively avoiding the problem of difficult processing technology caused by the third lens being too thin, reducing the size of the optical system and maintaining its miniaturized characteristics. At the same time, it is also beneficial to reduce the sensitivity of the optical system.

[0054] In one embodiment, the optical system satisfies the relationship: 0.8 < (R51 + R52) / (R51 - R52) < 1.6; where R51 is the radius of curvature of the object-side surface of the fifth lens at the optical axis, and R52 is the radius of curvature of the image-side surface of the fifth lens at the optical axis. Specifically, the value of (R51 + R52) / (R51 - R52) can be 1.072, 0.992, 0.805, 0.839, 1.020, 1.586, 1.298, 1.467, etc.

[0055] By ensuring that the optical system satisfies the above relationship, it is beneficial to reasonably control the curvature radius of the object side and image side of the fifth lens, thereby effectively controlling the shape of the fifth lens, shortening the overall length of the optical system, maintaining its miniaturization characteristics, and enabling the fifth lens to refract incident light more gently, avoiding increased aberrations. It is also beneficial to correct the aberrations of the first to fourth lenses, thereby improving the imaging effect of the optical system.

[0056] In one embodiment, the optical system satisfies the relationship: 3.5 < |R51| / f < 166; where R51 is the radius of curvature of the object-side surface of the fifth lens at the optical axis, and f is the effective focal length of the optical system. Specifically, the value of |R51| / f can be 16.163, 165.892, 10.989, 10.518, 84.825, 3.852, 35.743, 132.13, etc.

[0057] 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 of the fifth lens at the optical axis to the effective focal length of the optical system, effectively control the bending degree of the object side of the fifth lens, optimize the refractive power of the fifth lens, reduce the sensitivity of the optical system, and improve the imaging quality of the optical system.

[0058] In one embodiment, the optical system further includes an aperture stop located between the first lens and the second lens. The optical system satisfies the relationship: 0.72 ≤ SL / TTL < 0.78; where SL is the distance from the aperture stop to the imaging plane of the optical system along the optical axis, and TTL is the distance from the object side of the first lens to the imaging plane of the optical system along the optical axis. Specifically, the value of SL / TTL can be 0.740, 0.735, 0.743, 0.728, 0.764, 0.740, 0.752, 0.771, etc.

[0059] By making the optical system satisfy the above relationship, it is beneficial to reasonably set the aperture stop in the optical system, increase the aperture of the aperture stop, so as to effectively control the incident angle of the marginal field light when entering the optical system, adjust the light input amount of the optical system, improve the relative brightness of the marginal field, and further improve the imaging quality. Below the lower limit of the relationship, the total length of the optical system is too large, which is not conducive to meeting the requirement of the optical system being thin and light; exceeding the upper limit of the relationship, the object space imaging range of the optical system is too small, which is not conducive to meeting the requirement of the optical system being wide-angle.

[0060] In one embodiment, the optical system satisfies the relationship: 2.69 < TTL / ImgH ≤ 2.8; where, TTL is the distance from the object side surface of the first lens to the imaging surface of the optical system on the optical axis, and 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 2.793, 2.800, 2.695, 2.710, 2.800, 2.786, 2.739, 2.763, etc.

[0061] By making the optical system satisfy the above relationship, it is beneficial to meet the requirement of high imaging quality. At the same time, it is also beneficial to compress the overall length of the optical system, make the structure of the optical system more compact, and meet the requirement of the optical system being miniaturized.

[0062] In one embodiment, the optical system satisfies the relationship: 0 < AT45 / ET5 ≤ 0.1; where, AT45 is the distance from the image side surface of the fourth lens to the object side surface of the fifth lens on the optical axis, and ET5 is the edge thickness of the fifth lens. Specifically, the value of AT45 / ET5 can be 0.090, 0.088, 0.098, 0.098, 0.084, 0.092, 0.095, 0.087, etc.

[0063] By making the optical system satisfy the above relationship, it is beneficial to reasonably configure the edge thickness of the fifth lens, provide a suitable deflection angle for the marginal light, reduce the aberration. At the same time, it is also beneficial to regulate the positional relationship between the fourth lens and the fifth lens, make the interval distance between the fourth lens and the fifth lens reasonable, improve the manufacturability of the optical system, and use this interval distance to reduce the aberration and tolerance sensitivity.

[0064] In one embodiment, the optical system satisfies the relationship: 3 < |R41 / ET4| < 6.4; where, R41 is the curvature radius of the object side surface of the fourth lens on the optical axis, and ET4 is the edge thickness of the fourth lens. Specifically, the value of |R41 / ET4| can be 3.389, 3.736, 3.964, 4.591, 3.033, 6.355, 5.298, 6.167, etc.

[0065] 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 edge thickness of the fourth lens, so that the light rays converged by the first lens and the second lens gradually diverge at the fourth lens, avoiding excessive deflection angles of the light rays in the optical system and increasing the sensitivity of the optical system. When the above relationship is satisfied and ET4 < 0.51, the fourth lens is meniscus-shaped, the refractive power of the fourth lens changes, the aberration introduced by the object side of the fourth lens is small, and the aberration introduced by the image side of the fourth lens can cooperate with other lenses to correct the overall aberration of the optical system, making the refractive power of the optical system reasonably configured, and thus improving the imaging quality of the optical system; when ET4 < 0.2, it is difficult to balance the thickness of the fourth lens on the optical axis and the edge thickness, increasing the manufacturing difficulty of the lens.

[0066] In one embodiment, the optical system satisfies the relationship: 0.85 < |Y52 / Y11| < 1.04; where Y52 is the maximum effective radius of the image side of the fifth lens, and Y11 is the maximum effective radius of the object side of the first lens. Specifically, the value of |Y52 / Y11| can be 0.895, 0.892, 1.022, 0.935, 0.926, 1.027, 1.038, 0.857, etc.

[0067] By making the optical system satisfy the above relationship, it is beneficial to reasonably configure the ratio of the maximum effective radius of the image side of the fifth lens to the maximum effective radius of the object side of the first lens, increase the incident angle of the light rays, expand the viewing angle of the optical system, and is also beneficial to improving the imaging quality of the optical system.

[0068] In one embodiment, the optical system satisfies the relationship: 0.79 < SD11 / ImgH < 0.92; where SD11 is the maximum effective aperture of the object side of the first lens, and ImgH is half of the image height corresponding to the maximum viewing angle of the optical system. Specifically, the value of SD11 / ImgH can be 0.900, 0.910, 0.800, 0.880, 0.870, 0.860, 0.851, 0.893, etc.

[0069] By making the optical system satisfy the above relationship, it is beneficial to control the ratio of the maximum effective aperture of the object side of the first lens to the image height corresponding to the maximum viewing angle of the optical system within a reasonable range, ensure that the effective aperture of the first lens remains within a reasonable range, make the aperture sizes of each lens appropriate, be beneficial to the design and manufacture of a miniaturized lens barrel, ensure the feasibility of miniaturization, and thus improve the compactness of the optical system structure. At the same time, it is also beneficial to improve the refractive ability of the first lens to light, and thus reduce distortion and aberration.

[0070] In one embodiment, the optical system satisfies the relationship: -0.4 < (CT2 / R21) + (CT2 / R22) < 0.65; where CT2 is the thickness of the second lens along the optical axis, R21 is the radius of curvature of the object-side surface of the second lens along the optical axis, and R22 is the radius of curvature of the image-side surface of the second lens along the optical axis. Specifically, the value of (CT2 / R21) + (CT2 / R22) can be -0.272, -0.246, -1.227, 0.629, 0.024, -0.391, 0.154, -0.167, etc.

[0071] By ensuring that the optical system satisfies the above relationship, it is beneficial to rationally configure the thickness of the second lens on the optical axis and the curvature radius of the object side and image side of the second lens, thereby improving the manufacturing yield of the second lens. At the same time, it is also beneficial to correct aberrations and improve the imaging quality of the optical system.

[0072] In some embodiments, the optical system further includes a filter, which can be an infrared cut-off filter or an infrared bandpass filter. The infrared cut-off filter is used to filter out infrared light, while the infrared bandpass filter only allows infrared light to pass through. In this application, the filter is an infrared cut-off filter, which is fixedly disposed relative to each lens in the optical system. The infrared cut-off filter is used to prevent infrared light from reaching the imaging surface of the optical system and interfering with normal imaging. The filter can be assembled together with each lens as part of the optical system. In other embodiments, the filter can also be a component independent of the optical system, and the filter can be installed between the optical system and the photosensitive chip during the assembly of the optical system and the photosensitive chip. It is understood that the filter can be made of optical glass coating, colored glass, or other materials, and can be selected according to actual needs. This embodiment does not make specific limitations. In other embodiments, the filtering function can also be achieved by providing a filter coating on at least one of the first to fifth lenses.

[0073] First Embodiment

[0074] Please refer to Figure 1a The optical system 10 of this embodiment includes, from the object side to the image side along the optical axis:

[0075] The first lens L1 has negative refractive power. The object side S1 of the first lens L1 is concave near the optical axis, and the image side S2 is concave near the optical axis.

[0076] The second lens L2 has positive refractive power. The object side S3 of the second lens L2 is convex near the optical axis, and the image side S4 is convex near the optical axis.

[0077] The third lens L3 has negative refractive power. The object side S5 of the third lens L3 is convex near the optical axis, and the image side S6 is concave near the optical axis.

[0078] The fourth lens L4 has positive refractive power. The object side S7 of the fourth lens L4 is convex near the optical axis, and the image side S8 is convex near the optical axis.

[0079] The fifth lens L5 has negative refractive power. The object side S9 of the fifth lens L5 is convex near the optical axis, and the image side S10 is concave near the optical axis.

[0080] In addition, the optical system 10 also includes an aperture stop STO, an IR filter, and an imaging surface IMG. In this embodiment, the aperture stop STO is disposed between the image-side surface of the first lens L1 and the object-side surface of the second lens L2 in the optical system 10, and is used to control the amount of light entering the system. The IR filter is disposed between the fifth lens L5 and the imaging surface IMG, and includes an object-side surface S11 and an image-side surface S12. The IR filter is an infrared cut-off filter, which is used to filter out infrared light, so that the light entering the imaging surface IMG is only visible light. The wavelength of visible light is 380nm-780nm. The infrared cut-off filter can be made of glass or plastic, and a coating can be deposited on its surface. The materials of the first lens L1 to the fifth lens L5 can be glass or plastic. The effective pixel area of ​​the photosensitive chip is located on the imaging surface. A visible light photosensitive chip is disposed at the imaging surface IMG. The photosensitive chip captures different wavelength information of the object for subsequent processing.

[0081] Table 1a shows the parameters of the optical system 10 of this embodiment, 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. 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, and the second value is the distance on the optical axis from the image-side surface of the lens to the next surface in the image-side direction. The focal length, material refractive index, and Abbe number are all obtained using visible light with a reference wavelength of 587.6 nm, and the units for Y-radius, thickness, and focal length are millimeters (mm).

[0082] Table 1a

[0083]

[0084]

[0085] Where 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, and TTL is the distance from the object side of the first lens to the imaging surface on the optical axis, i.e., the total optical length.

[0086] In this embodiment, the object-side surface and image-side surface of the first lens L1 to the fifth lens L5 are both aspherical surfaces. The surface shape x of the aspherical surface can be defined using, but is not limited to, the following aspherical surface formula:

[0087]

[0088] 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, 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 A2, A4, A6, A8, A10, A12, A14, and A16 of the aspherical mirrors S3, S4, S5, S6, S7, S8, S9, S10, S11, and S12 that can be used in the first embodiment.

[0089] Table 1b

[0090] Face number k A4 A6 A8 A10 S1 2.5360E+00 1.9778E-01 -1.3847E-01 1.0419E-01 -6.6004E-02 S2 2.1889E-01 3.0644E-01 5.2217E-01 -4.0402E+00 1.7736E+01 S3 -8.1807E+00 -6.0072E-02 -7.7398E-01 -1.9889E+00 1.7052E+02 S4 -8.4160E-01 -6.1840E-01 8.9751E-01 -1.7394E+00 -1.6967E+00 S5 -4.5965E+01 -2.7917E-01 -1.6347E-01 2.5316E+00 -1.4549E+01 S6 -7.7831E+00 -5.8574E-02 -8.2238E-02 2.0987E-01 -4.5088E-01 S7 -1.5615E+01 1.6665E-01 -5.0746E-01 1.2074E+00 -1.9038E+00 S8 -1.2681E+00 -1.4533E-01 6.1718E-01 -1.2322E+00 1.6198E+00 S9 -6.2846E-01 -7.5136E-01 1.3131E+00 -1.7433E+00 1.6858E+00 S10 -6.3909E+00 -2.4918E-01 3.1374E-01 -2.8439E-01 1.8040E-01 Face number A12 A14 A16 A18 A20 S1 3.1917E-02 -1.0942E-02 2.4728E-03 -3.2819E-04 1.9372E-05 S2 -4.3859E+01 6.2994E+01 -4.9330E+01 1.7693E+01 -1.6909E+00 S3 -2.4328E+03 1.7184E+04 -6.6838E+04 1.3624E+05 -1.1371E+05 S4 2.6203E+01 -9.0250E+01 1.5628E+02 -1.3951E+02 5.0511E+01 S5 4.7983E+01 -9.6742E+01 1.1787E+02 -7.9738E+01 2.3028E+01 S6 6.6833E-01 -7.4253E-01 6.0392E-01 -3.0361E-01 6.8111E-02 S7 1.9631E+00 -1.3106E+00 5.4201E-01 -1.2516E-01 1.2251E-02 S8 -1.3576E+00 7.3761E-01 -2.5581E-01 5.2006E-02 -4.7216E-03 S9 -1.1239E+00 4.9624E-01 -1.3641E-01 2.0888E-02 -1.3510E-03 S10 -7.7317E-02 2.1656E-02 -3.7709E-03 3.6891E-04 -1.5454E-05

[0091] Figure 1b Figure (a) shows the longitudinal spherical aberration curves of the optical system 10 of the first embodiment at wavelengths of 650.0000 nm, 610.0000 nm, 587.6000 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. 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 1b As can be seen in (a), the convergence focus of each wavelength of light in the first embodiment tends to be consistent, and the blur spots or color halos in the image are effectively suppressed, indicating that the imaging quality of the optical system 10 in this embodiment is good.

[0092] Figure 1b Figure (b) shows the astigmatism curve of the optical system 10 of the first embodiment at a wavelength of 587.6000 nm, where the horizontal axis along the X-axis represents the focus 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 587.6000 nm, and the T-curve represents the meridional field curvature at 587.6000 nm. Figure 1bAs 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 both the center and edge of the field of view.

[0093] Figure 1b Image (c) shows the distortion curve of the optical system 10 of the first embodiment at a wavelength of 587.6000 nm. The horizontal axis along the X-axis represents the distortion value, denoted as %, and the vertical axis along the Y-axis represents the image height, in mm. The distortion curve represents the distortion magnitude corresponding to different field of view angles. Figure 1b As can be seen in (c), at a wavelength of 587.6000 nm, the image distortion caused by the main beam is small, and the imaging quality of the system is excellent.

[0094] Depend on Figure 1b As can be seen from (a), (b) and (c), the optical system 10 of this embodiment has small aberrations and good imaging quality, and has good imaging quality.

[0095] Second Embodiment

[0096] Please refer to Figure 2a The optical system 10 of this embodiment includes, from the object side to the image side along the optical axis:

[0097] The first lens L1 has negative refractive power. The object side S1 of the first lens L1 is concave near the optical axis, and the image side S2 is concave near the optical axis.

[0098] The second lens L2 has positive refractive power. The object side S3 of the second lens L2 is convex near the optical axis, and the image side S4 is convex near the optical axis.

[0099] The third lens L3 has negative refractive power. The object side S5 of the third lens L3 is convex near the optical axis, and the image side S6 is concave near the optical axis.

[0100] The fourth lens L4 has positive refractive power. The object side S7 of the fourth lens L4 is convex near the optical axis, and the image side S8 is convex near the optical axis.

[0101] The fifth lens L5 has negative refractive power. The object side S9 of the fifth lens L5 is concave near the optical axis, and the image side S10 is concave near the optical axis.

[0102] The other structures of the second embodiment are the same as those of the first embodiment, and can be referred to accordingly.

[0103] Table 2a 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 587.6 nm. The units for Y radius, thickness and focal length are millimeters (mm). The meanings of the other parameters are the same as those in the first embodiment.

[0104] Table 2a

[0105]

[0106] Where f is the 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, and TTL is the distance from the object side of the first lens to the imaging surface on the optical axis, i.e., the total optical length.

[0107] 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.

[0108] Table 2b

[0109] Face number k A4 A6 A8 A10 S1 2.5271E+00 2.0026E-01 -1.4125E-01 1.0634E-01 -6.7444E-02 S2 1.2401E+00 3.4922E-01 -2.4864E-01 2.4549E+00 -1.3599E+01 S3 -2.8510E+00 -5.2015E-02 -7.6640E-01 -1.9654E+00 1.7061E+02 S4 -7.9909E-01 -5.8519E-01 6.1233E-02 5.6181E+00 -3.8232E+01 S5 -5.0760E+01 -2.5215E-01 -4.9197E-01 3.7864E+00 -1.6738E+01 S6 -7.6513E+00 -3.5761E-02 -2.7315E-01 9.6843E-01 -2.3074E+00 S7 -1.5769E+01 1.3168E-01 -3.7870E-01 9.5455E-01 -1.5703E+00 S8 -1.2560E+00 -1.5139E-01 6.2076E-01 -1.1697E+00 1.4686E+00 S9 4.1968E+01 -6.8462E-01 1.1230E+00 -1.3780E+00 1.1986E+00 S10 -5.3012E+00 -2.7925E-01 3.7196E-01 -3.4772E-01 2.2017E-01 Face number A12 A14 A16 A18 A20 S1 3.2721E-02 -1.1251E-02 2.5451E-03 -3.3729E-04 1.9818E-05 S2 4.7744E+01 -1.0170E+02 1.2830E+02 -8.7072E+01 2.4122E+01 S3 -2.4328E+03 1.7184E+04 -6.6838E+04 1.3624E+05 -1.1371E+05 S4 1.4061E+02 -3.1924E+02 4.3944E+02 -3.3626E+02 1.0913E+02 S5 4.7945E+01 -8.9153E+01 1.0367E+02 -6.8461E+01 1.9622E+01 S6 3.6551E+00 -3.8462E+00 2.5908E+00 -1.0112E+00 1.7453E-01 S7 1.6611E+00 -1.1249E+00 4.6903E-01 -1.0891E-01 1.0708E-02 S8 -1.1997E+00 6.4353E-01 -2.2158E-01 4.4839E-02 -4.0620E-03 S9 -7.2710E-01 3.0487E-01 -8.2929E-02 1.2871E-02 -8.5186E-04 S10 -9.3860E-02 2.6450E-02 -4.6895E-03 4.7075E-04 -2.0309E-05

[0110] Figure 2b Images (a), (b), and (c) respectively show the longitudinal spherical aberration curve, astigmatism curve, and distortion curve of the optical system 10 at different focal lengths in 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 of view angles. Figure 2b As can be seen from the aberration diagram, the longitudinal spherical aberration, field curvature, and distortion of the optical system 10 are well controlled, thus the optical system 10 of this embodiment has good imaging quality.

[0111] Third Embodiment

[0112] Please refer to Figure 3a The optical system 10 of this embodiment includes, from the object side to the image side along the optical axis:

[0113] The first lens L1 has negative refractive power. The object side S1 of the first lens L1 is concave near the optical axis, and the image side S2 is concave near the optical axis.

[0114] The second lens L2 has negative refractive power. The object side S3 of the second lens L2 is convex near the optical axis, and the image side S4 is concave near the optical axis.

[0115] The third lens L3 has positive refractive power. The object side S5 of the third lens L3 is convex near the optical axis, and the image side S6 is concave near the optical axis.

[0116] The fourth lens L4 has positive refractive power. The object side S7 of the fourth lens L4 is convex near the optical axis, and the image side S8 is convex near the optical axis.

[0117] The fifth lens L5 has negative refractive power. The object side S9 of the fifth lens L5 is concave near the optical axis, and the image side S10 is concave near the optical axis.

[0118] The other structures of the third embodiment are the same as those of the first embodiment, and can be referred to accordingly.

[0119] 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 587.6 nm. The units for Y radius, thickness and focal length are millimeters (mm). The meanings of the other parameters are the same as those in the first embodiment.

[0120] Table 3a

[0121]

[0122] Where f is the 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, and TTL is the distance from the object side of the first lens to the imaging surface on the optical axis, i.e., the total optical length.

[0123] 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.

[0124] Table 3b

[0125] Face number k A4 A6 A8 A10 S1 2.4122E+00 1.8776E-01 -1.3341E-01 9.8859E-02 -6.2801E-02 S2 3.3935E-01 3.4476E-01 -5.2088E-01 3.5704E+00 -1.9080E+01 S3 3.7080E+00 -6.5783E-02 -7.5689E-01 -1.7801E+00 1.7116E+02 S4 -9.9000E+01 -1.2732E+00 7.2443E+00 -3.7806E+01 1.2354E+02 S5 -2.8187E+01 2.3645E-02 2.2840E+00 -3.8488E+01 2.2051E+02 S6 -9.4471E+00 -8.7766E-02 -6.0583E-01 4.7226E+00 -1.7771E+01 S7 -1.5585E+01 -2.2450E-03 4.3179E-01 -1.2028E+00 1.7283E+00 S8 -1.3301E+00 -1.7071E-01 4.1584E-01 -1.4311E-01 -4.6092E-01 S9 5.2226E+01 -5.9663E-01 1.0728E+00 -1.8265E+00 2.0050E+00 S10 -6.1205E+00 -1.7472E-01 1.2059E-01 -1.0942E-01 8.3664E-02 Face number A12 A14 A16 A18 A20 S1 3.0911E-02 -1.0907E-02 2.5599E-03 -3.5525E-04 2.2080E-05 S2 6.8796E+01 -1.4661E+02 1.7794E+02 -1.1385E+02 2.9756E+01 S3 -2.4328E+03 1.7184E+04 -6.6838E+04 1.3624E+05 -1.1371E+05 S4 -2.2655E+02 1.5854E+02 1.5661E+02 -3.4758E+02 1.7034E+02 S5 -7.0980E+02 1.3882E+03 -1.6323E+03 1.0597E+03 -2.9135E+02 S6 3.7501E+01 -4.7276E+01 3.5722E+01 -1.4974E+01 2.6768E+00 S7 -1.4509E+00 7.0077E-01 -1.7731E-01 1.7367E-02 2.4919E-04 S8 8.4458E-01 -6.6819E-01 2.7770E-01 -5.8173E-02 4.7761E-03 S9 -1.3463E+00 5.7351E-01 -1.5297E-01 2.3224E-02 -1.5192E-03 S10 -4.5726E-02 1.6881E-02 -3.8685E-03 4.8727E-04 -2.5596E-05

[0126] Figure 3b Images (a), (b), and (c) respectively show the longitudinal spherical aberration curve, astigmatism curve, and distortion curve of the optical system 10 at different focal lengths in 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 of view angles. Figure 3b As can be seen from the aberration diagram, the longitudinal spherical aberration, field curvature, and distortion of the optical system 10 are well controlled, thus the optical system 10 of this embodiment has good imaging quality.

[0127] Fourth embodiment

[0128] Please refer to Figure 4a The optical system 10 of this embodiment includes, from the object side to the image side along the optical axis:

[0129] The first lens L1 has negative refractive power. The object side S1 of the first lens L1 is concave near the optical axis, and the image side S2 is concave near the optical axis.

[0130] The second lens L2 has positive refractive power. The object side S3 of the second lens L2 is convex near the optical axis, and the image side S4 is concave near the optical axis.

[0131] The third lens L3 has positive refractive power. The object side S5 of the third lens L3 is convex near the optical axis, and the image side S6 is concave near the optical axis.

[0132] The fourth lens L4 has positive refractive power. The object side S7 of the fourth lens L4 is convex near the optical axis, and the image side S8 is convex near the optical axis.

[0133] The fifth lens L5 has negative refractive power. The object side S9 of the fifth lens L5 is concave near the optical axis, and the image side S10 is concave near the optical axis.

[0134] The other structures of the fourth embodiment are the same as those of the first embodiment, and can be referred to accordingly.

[0135] 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 587.6 nm. The units for Y radius, thickness and focal length are millimeters (mm). The meanings of the other parameters are the same as those in the first embodiment.

[0136] Table 4a

[0137]

[0138] Where f is the 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, and TTL is the distance from the object side of the first lens to the imaging surface on the optical axis, i.e., the total optical length.

[0139] 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.

[0140] Table 4b

[0141]

[0142]

[0143] Figure 4bImages (a), (b), and (c) respectively show the longitudinal spherical aberration curve, astigmatism curve, and distortion curve of the optical system 10 at different focal lengths in 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 of view angles. Figure 4b As can be seen from the aberration diagram, the longitudinal spherical aberration, field curvature, and distortion of the optical system 10 are well controlled, thus the optical system 10 of this embodiment has good imaging quality.

[0144] Fifth embodiment

[0145] Please refer to Figure 5a The optical system 10 of this embodiment includes, from the object side to the image side along the optical axis:

[0146] The first lens L1 has negative refractive power. The object side S1 of the first lens L1 is concave near the optical axis, and the image side S2 is concave near the optical axis.

[0147] The second lens L2 has negative refractive power. The object side S3 of the second lens L2 is concave near the optical axis, and the image side S4 is concave near the optical axis.

[0148] The third lens L3 has positive refractive power. The object side S5 of the third lens L3 is convex near the optical axis, and the image side S6 is concave near the optical axis.

[0149] The fourth lens L4 has positive refractive power. The object side S7 of the fourth lens L4 is convex near the optical axis, and the image side S8 is convex near the optical axis.

[0150] The fifth lens L5 has negative refractive power. The object side S9 of the fifth lens L5 is convex near the optical axis, and the image side S10 is concave near the optical axis.

[0151] The other structures of the fifth embodiment are the same as those of the first embodiment, and can be referred to accordingly.

[0152] Table 5a 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 587.6 nm. The units for Y radius, thickness and focal length are millimeters (mm). The meanings of the other parameters are the same as those in the first embodiment.

[0153] Table 5a

[0154]

[0155]

[0156] Where f is the 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, and TTL is the distance from the object side of the first lens to the imaging surface on the optical axis, i.e., the total optical length.

[0157] 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.

[0158] Table 5b

[0159] Face number k A4 A6 A8 A10 S1 2.5995E+00 2.1202E-01 -1.5753E-01 1.1710E-01 -7.2915E-02 S2 2.9815E+00 2.4297E-01 1.4533E-01 -7.2499E-01 2.7885E+00 S3 9.9000E+01 -9.1205E-02 -7.5776E-01 -1.8813E+00 1.7081E+02 S4 -9.9000E+01 -1.9336E+00 9.1575E+00 -5.4724E+01 2.6844E+02 S5 -1.8002E+01 -2.4944E-02 -2.0031E+00 9.4514E+00 -2.9128E+01 S6 -8.3376E+00 -1.5636E-02 -2.5343E-01 2.3750E-01 5.9751E-01 S7 -1.3276E+01 1.4751E-01 -3.9777E-01 8.3116E-01 -1.1190E+00 S8 -1.2106E+00 -1.7920E-01 6.3497E-01 -7.8392E-01 2.3255E-01 S9 9.9000E+01 -6.5769E-01 1.1702E+00 -1.6761E+00 1.7168E+00 S10 -5.1987E+00 -2.3172E-01 1.9176E-01 -7.2226E-02 -1.6090E-02 Face number A12 A14 A16 A18 A20 S1 3.4437E-02 -1.1332E-02 2.4082E-03 -2.9546E-04 1.5979E-05 S2 -7.6525E+00 1.3374E+01 -1.3313E+01 6.8637E+00 -1.4526E+00 S3 -2.4328E+03 1.7184E+04 -6.6838E+04 1.3624E+05 -1.1371E+05 S4 -9.3511E+02 2.1669E+03 -3.1478E+03 2.5762E+03 -9.0316E+02 S5 6.2847E+01 -9.1892E+01 8.6708E+01 -4.8044E+01 1.1919E+01 S6 -2.0716E+00 2.7468E+00 -1.9270E+00 7.0299E-01 -1.0494E-01 S7 9.7810E-01 -5.6293E-01 2.0626E-01 -4.3275E-02 3.9170E-03 S8 5.8077E-01 -7.6839E-01 4.1060E-01 -1.0457E-01 1.0407E-02 S9 -1.1710E+00 5.1847E-01 -1.4200E-01 2.1666E-02 -1.3995E-03 S10 3.0162E-02 -1.3284E-02 2.8343E-03 -3.0153E-04 1.2814E-05

[0160] Figure 5b Images (a), (b), and (c) respectively show the longitudinal spherical aberration curve, astigmatism curve, and distortion curve of the optical system 10 at different focal lengths in 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 of view angles. Figure 5b As can be seen from the aberration diagram, the longitudinal spherical aberration, field curvature, and distortion of the optical system 10 are well controlled, thus the optical system 10 of this embodiment has good imaging quality.

[0161] Sixth Embodiment

[0162] Please refer to Figure 6a The optical system 10 of this embodiment includes, from the object side to the image side along the optical axis:

[0163] The first lens L1 has positive refractive power. The object side S1 of the first lens L1 is concave near the optical axis, and the image side S2 is concave near the optical axis.

[0164] The second lens L2 has positive refractive power. The object side S3 of the second lens L2 is convex near the optical axis, and the image side S4 is convex near the optical axis.

[0165] The third lens L3 has negative refractive power. The object side S5 of the third lens L3 is concave near the optical axis, and the image side S6 is concave near the optical axis.

[0166] The fourth lens L4 has positive refractive power. The object side S7 of the fourth lens L4 is convex near the optical axis, and the image side S8 is convex near the optical axis.

[0167] The fifth lens L5 has negative refractive power. The object side S9 of the fifth lens L5 is convex near the optical axis, and the image side S10 is concave near the optical axis.

[0168] The other structures of the sixth embodiment are the same as those of the first embodiment, and can be referred to accordingly.

[0169] Table 6a 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 587.6 nm. The units for Y radius, thickness and focal length are millimeters (mm). The meanings of the other parameters are the same as those in the first embodiment.

[0170] Table 6a

[0171]

[0172] Where f is the 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, and TTL is the distance from the object side of the first lens to the imaging surface on the optical axis, i.e., the total optical length.

[0173] 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.

[0174] Table 6b

[0175]

[0176]

[0177] Figure 6b Images (a), (b), and (c) respectively show the longitudinal spherical aberration curve, astigmatism curve, and distortion curve of the optical system 10 at different focal lengths in 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 of view angles. Figure 6b As can be seen from the aberration diagram, the longitudinal spherical aberration, field curvature, and distortion of the optical system 10 are well controlled, thus the optical system 10 of this embodiment has good imaging quality.

[0178] Table 7 shows the values ​​of f3 / f2, CT2 / CT3, f / T12, CT5 / CT4, (R51+R52) / (R51-R52), SL / TTL, AT45 / ET5, |R41 / ET4|, |Y52 / Y11|, (CT2 / R21)+(CT2 / R22), FOV, |R51| / f, CT4 / CT1, SD11 / ImgH, and TTL / ImgH in the optical systems of the first to sixth embodiments.

[0179] Table 7

[0180]

[0181] As can be seen from Table 7, the optical systems of the first to sixth embodiments all satisfy the following relationships: -6.55 < f3 / f2 < 1.25, 1.15 < CT2 / CT3 < 1.75, 1.35 < f / T12 < 1.95, 0.35 < CT5 / CT4 < 0.55, 0.8 < (R51 + R52) / (R51 - R52) < 1.6, 0.72 ≤ SL / TTL < 0.78, 0 < AT45 / ET5 ≤ 0.1, 3 < |R41 / ET4| < 6.4, 0.85 < |Y52 / Y11| < 1.04, -0.4 < (CT2 / R21) + (CT2 / R22) < 0.65, 120deg < FOV ≤ 140deg, 3.5 < |R51| / f < 166, 1.82 < CT4 / CT1 < 2.7, 0.79 < SD11 / ImgH < 0.92, 2.69 < TTL / ImgH ≤ 2.8.

[0182] Please refer to Figure 7 , the present invention also provides an imaging module 20, which includes a photosensitive chip 21 and the optical system 10 according to any one of the embodiments of the first aspect. The photosensitive chip 21 is disposed on the image side of the optical system 10. Among them, 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 an image. The photosensitive chip 21 can be a Complementary Metal Oxide Semiconductor (CMOS) or a Charge-coupled Device (CCD). The imaging module 20 can be an imaging module integrated on an electronic device 30 or an independent lens. By adding the optical system 10 provided by the present invention to the imaging module 20, it is possible to reasonably design the surface shape and refractive power of each lens in the optical system 10, so that the imaging module 20 satisfies a large viewing angle, miniaturization and has a good imaging effect.

[0183] Please refer to Figure 8 , the present invention also provides an electronic device 30, which includes a housing 31 and the above imaging module 20. The imaging module 20 is disposed in the housing 31. The electronic device 30 includes, but is not limited to, an automobile, a monitor, a smart phone, a computer, a smart watch, etc. By adding the imaging module 20 provided by the present invention to the electronic device 30, the electronic device 30 satisfies a large viewing angle, miniaturization and has a good imaging effect.

[0184] 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, There are a total of five lenses with refractive power, which successively include, from the object side to the image side along the optical axis: The first lens, which has refractive power, and both the object side surface and the image side surface of the first lens are concave surfaces near the optical axis; The second lens, which has refractive power; The third lens, which has refractive power, and the image side surface of the third lens is a concave surface near the optical axis; The fourth lens, which has positive refractive power, and both the object side surface and the image side surface of the fourth lens are convex surfaces near the optical axis; The fifth lens, which has negative refractive power, and the image side surface of the fifth lens is a concave surface near the optical axis; The optical system satisfies the relation: 120deg < FOV < 140deg; Wherein, FOV is the maximum field angle of view of the optical system; 2. The optical system as described in claim 1, characterized in that, The optical system satisfies the relation: 1.35 < f / T12 < 1.95, and / or -6.55 < f3 / f2 < 1.25; Wherein, f is the effective focal length of the optical system, T12 is the distance on the optical axis from the image side surface of the first lens to the object side surface of the second lens, f3 is the effective focal length of the third lens, and f2 is the effective focal length of the second lens; 3. The optical system as described in claim 1, characterized in that, The optical system satisfies the relation: 0.35 < CT5 / CT4 < 0.55, and / or 1.15 < CT2 / CT3 < 1.75, and / or 1.82 < CT4 / CT1 < 2.7; Wherein, CT5 is the thickness of the fifth lens on the optical axis, CT4 is the thickness of the fourth lens on the optical axis, CT2 is the thickness of the second lens on the optical axis, CT3 is the thickness of the third lens on the optical axis, and CT1 is the thickness of the first lens on the optical axis; 4. The optical system as claimed in claim 1, characterized in that, The optical system satisfies the relation: 0.8 < (R51 + R52) / (R51 - R52) < 1.6, and / or 3.5 < |R51| / f < 166; Wherein, R51 is the radius of curvature of the object side surface of the fifth lens at the optical axis, R52 is the radius of curvature of the image side surface of the fifth lens at the optical axis, and f is the effective focal length of the optical system; 5. The optical system as claimed in claim 1, characterized in that, The optical system further includes an aperture stop, and the aperture stop is located between the first lens and the second lens, and the optical system satisfies the relation: 0.72 ≤ SL / TTL < 0.78, and / or 2.69 < TTL / ImgH ≤ 2.8; Wherein, SL is the distance on the optical axis from the aperture stop to the imaging surface of the optical system, TTL is the distance on the optical axis from the object side surface of the first lens to the imaging surface of the optical system, and ImgH is half of the image height corresponding to the maximum field angle of view of the optical system; 6. The optical system as claimed in claim 1, characterized in that, The optical system satisfies the relation: 0 < AT45 / ET5 ≤ 0., and / or 3 < |R41 / ET4| < 6.4; Wherein, AT45 is the distance on the optical axis from the image side surface of the fourth lens to the object side surface of the fifth lens, ET5 is the edge thickness of the fifth lens, R41 is the radius of curvature of the object side surface of the fourth lens at the optical axis, and ET4 is the edge thickness of the fourth lens; 7. The optical system as claimed in claim 1, characterized in that, The optical system satisfies the relation: 0.85 < |Y52 / Y11| < 1.04, and / or 0.79 <SD11 / ImgH<0.92; Wherein, Y52 is the maximum effective radius of the image side of the fifth lens, Y11 is the maximum effective radius of the object side of the first lens, SD11 is the maximum effective aperture of the object side of the first lens, and ImgH is half the image height corresponding to the maximum field of view of the optical system.

8. The optical system as claimed in claim 1, characterized in that, The optical system satisfies the following relationship: -0.4<(CT2 / R21)+(CT2 / R22)<0.65; Wherein, CT2 is the thickness of the second lens on the optical axis, R21 is the radius of curvature of the object side of the second lens on the optical axis, and R22 is the radius of curvature of the image side of the second lens on the optical axis.

9. A camera module, characterized in that, The optical system and photosensitive chip according to any one of claims 1 to 8 are included, 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 as described in claim 9, wherein the camera module is disposed within the housing.

Images