An ultra-wide-angle, small-head, lightweight optical system

Abstract

The embodiment of the present invention discloses an ultra-wide-angle, small-head, lightweight optical system, which is mainly composed of 5 lenses. Through the reasonable distribution of optical focal length and the optimized selection of high-order aspheric parameters, it can meet the market demand for optical lenses with a small head and lightness on the basis of satisfying the ultra-wide angle of the optical lens. The optical system configured by the present invention has the advantages of ultra-wide angle, small head, and lightness, has a compact structure, is easy to process and install, and at the same time, has good imaging resolution.

Description

Technical Field

[0001] The present application relates to the field of optical imaging, and in particular to an ultra-wide-angle, small-head, and lightweight optical system. Background Art

[0002] With the rapid development of the lens industry, the image quality of optical imaging lenses used in portable electronic products is becoming increasingly higher. At the same time, users are demanding increasingly smaller optical imaging lenses for these devices. For example, in smartphones, digital tablets, optical recognition devices, backup cameras, dashcams, and drones, lens quality requirements are becoming increasingly stringent, with increasingly stringent specifications. Furthermore, with the recent trend towards thinner and lighter electronic products, traditional camera modules struggle to simultaneously meet these high-quality and miniaturized requirements, particularly for miniature lenses with large apertures or wide viewing angles.

[0003] Specifically, in the prior art, configuring a lens with a wide viewing angle tends to increase the overall length, failing to meet the demand for miniaturization. Therefore, a camera that combines a wide viewing angle with miniaturization is needed to meet future market specifications and demands. Summary of the Invention

[0004] To overcome the problem that the optical systems of existing portable electronic products cannot meet the requirements of miniaturization due to the configuration of lenses with wide-viewing angle characteristics, the embodiments of the present invention disclose an ultra-wide-angle, miniaturized, and ultra-thin optical system. Through the reasonable distribution of optical focal length and the optimized selection of high-order aspheric surface parameters, it can achieve miniaturization while taking into account the lightweight and ultra-wide-angle shooting functions.

[0005] An ultra-wide-angle, small-head, lightweight optical system, which is composed of a first lens, an aperture, a second lens, a third lens, a fourth lens, and a fifth lens in sequence from the object plane to the image plane along the optical axis.

[0006] The image side surface of the first lens is concave and has negative optical power;

[0007] The object-side surface and image-side surface of the second lens are convex, and its optical power is positive;

[0008] The image side surface of the third lens is concave, and has an optical power

[0009] The object side surface of the fourth lens is convex and has positive optical power;

[0010] The object side surface of the fifth lens is concave and has negative optical power;

[0011] The optical system satisfies the following conditions: 33 < FOV / (DT11*TTL / IamgH) < 39; where FOV is the maximum field angle of the optical system, DT11 is the maximum effective radius of the object side surface of the first lens, TTL is the on-axis distance from the object side surface of the first lens to the imaging surface, and ImgH is half of the diagonal length of the effective pixel area on the imaging surface.

[0012] Preferably, the optical system satisfies the following conditions: -5 < f1*f4 / f < -4; -2.1 < (f4 - f3) / f3 < -0.7; where f1 is the effective focal length of the first lens, f3 is the effective focal length of the third lens, f4 is the effective focal length of the fourth lens, and f is the effective focal length of the optical system.

[0013] Preferably, the optical system satisfies the following conditions: 1.7 < f123 / f < 2.8; where f is the effective focal length of the optical system and f123 is the effective combined focal length of the first, second, and third lenses.

[0014] Preferably, the optical system satisfies the following conditions: -2.2 < f1*f2 / (R2 + R3) < -0.8; 0.5 < f2 / R3 < 1.2; where f1 is the effective focal length of the first lens, f2 is the effective focal length of the second lens, R2 is the curvature radius of the image side surface of the first lens, and R3 is the curvature radius of the object side surface of the second lens.

[0015] Preferably, the optical system satisfies the following conditions: 0.4 < |R8| / R2 < 1.2; where R2 is the curvature radius of the image side surface of the first lens and R8 is the curvature radius of the image side surface of the fourth lens.

[0016] Preferably, the optical system satisfies the following conditions: 2.0 < (CT4 + CT5) / BFL < 2.4; where CT4 is the central thickness of the fourth lens on the optical axis, CT5 is the central thickness of the fifth lens on the optical axis, and BFL is the shortest distance from the image side surface of the fifth lens to the imaging surface of the optical system in the direction of the optical axis.

[0017] Preferably, the optical system satisfies the following conditions: 5.0 < |DT52 - DT51 / DT42 - DT41| < 11.0; -6.1 < DT52 / SAG10 < -3.6; where DT41 is the maximum effective radius of the object side surface of the fourth lens, DT42 is the maximum effective radius of the image side surface of the fourth lens, DT51 is the maximum effective radius of the object side surface of the fifth lens, DT52 is the maximum effective radius of the image side surface of the fifth lens, and SAG10 is the distance parallel to the optical axis from the maximum effective clear aperture of the image side surface of the fifth lens to the intersection of the image side surface of the fifth lens and the optical axis.

[0018] Preferably, the optical system satisfies the following conditions: 0.5<(SAG9-SAG10) / (SAG7+SAG8)<2.1; wherein, SAG7 is the distance from the maximum effective aperture of the objective side of the fourth lens to the intersection of the objective side of the fourth lens and the optical axis in the direction parallel to the optical axis, SAG8 is the distance from the maximum effective aperture of the image side of the fourth lens to the intersection of the image side of the fourth lens and the optical axis in the direction parallel to the optical axis, SAG9 is the distance from the maximum effective aperture of the objective side of the fifth lens to the intersection of the objective side of the fifth lens and the optical axis in the direction parallel to the optical axis, and SAG10 is the distance from the maximum effective aperture of the image side of the fifth lens to the intersection of the image side of the fifth lens and the optical axis in the direction parallel to the optical axis.

[0019] Preferably, the maximum effective radius DT11 of the objective side of the first lens is ≤1.78 mm;

[0020] And / or the F number of the optical system is 2.2.

[0021] Preferably, the full field of view FOV and total optical length TTL of the optical system satisfy: FOV>130°, TTL≤6.8mm.

[0022] Compared with the prior art, the present invention has the following advantages:

[0023] The embodiment of the present invention discloses an ultra-wide-angle, small-head, lightweight optical system, which is mainly composed of 5 lenses. Through the reasonable distribution of optical focal length and the optimized selection of high-order aspheric parameters, it can meet the market demand for optical lenses with a small head and lightness on the basis of satisfying the ultra-wide angle of the optical lens. The optical system configured by the present invention has the advantages of ultra-wide angle, small head, and lightness, has a compact structure, is easy to process and install, and at the same time, has good imaging resolution. BRIEF DESCRIPTION OF THE DRAWINGS

[0024] In order to more clearly illustrate the technical solutions in the embodiments of the present application, the following briefly introduces the drawings required for describing the embodiments.

[0025] Figure 1 Schematic diagram of the structure of the optical system of Example 1 of the present application;

[0026] Figure 2 axial chromatic aberration, astigmatism, and distortion curves of the optical system of Example 1 of the present application;

[0027] Figure 3 Schematic diagram of the structure of the optical system of Example 2 of the present application;

[0028] Figure 4 axial chromatic aberration, astigmatism, and distortion curves of the optical system of Example 2 of the present application;

[0029] Figure 5 It is a schematic structural diagram of the optical system in Embodiment 3 of the present application;

[0030] Figure 6 It is a chromatic aberration, astigmatism and distortion curve diagram of the optical axis of the optical system in Embodiment 3 of the present application;

[0031] Figure 7 It is a schematic structural diagram of the optical system in Embodiment 4 of the present application;

[0032] Figure 8 It is a chromatic aberration, astigmatism and distortion curve diagram of the optical axis of the optical system in Embodiment 4 of the present application. Specific embodiments

[0033] As Figure 1-8 shown, the present application provides an ultra-wide-angle, small-head, thin and light optical system, which sequentially includes, along the optical axis from the object plane to the image plane: the first lens E1, the aperture STO, the second lens E2, the third lens E3, the fourth lens E4, the fifth lens E5, the infrared filter E6 and the imaging plane S13.

[0034] The image side of the first lens E1 is concave, and its optical power is negative;

[0035] The object side of the second lens E2 is convex, and the image side is convex, and its optical power is positive;

[0036] The image side of the third lens E3 is concave, and it has optical power

[0037] The object side of the fourth lens E4 is convex, and its optical power is positive;

[0038] The object side of the fifth lens E5 is concave, and its optical power is negative.

[0039] This optical system satisfies the following condition: 33 < FOV / (DT11 * TTL / IamgH) < 39; where FOV is the maximum field angle of the optical system, DT11 is the maximum effective radius of the object side of the first lens E1, TTL is the axial distance from the object side of the first lens E1 to the imaging plane, and ImgH is half of the diagonal length of the effective pixel area on the imaging plane. This relational expression reflects the constraint situation of the optical lens in terms of the field angle and thin and light characteristics. When the above relational expression is satisfied, it can meet the market demand for the small head and thin and light characteristics of the optical lens while ensuring that the optical lens has an ultra-wide angle. When exceeding the upper limit of the relational expression, on the basis of ensuring that the field angle of the optical lens is ultra-wide, DT11 * TTL / IamgH is further reduced, which will excessively compress the thin and light characteristics of the optical lens and is not conducive to the improvement of the performance of the optical lens. When lower than the lower limit of the relational expression, the thin and light characteristics of the optical lens are insufficient, which is not conducive to the miniaturized design of the optical lens.

[0040] Further, the optical system satisfies the following condition: -5 < f1*f4 / f < -4, where f1 is the effective focal length of the first lens E1, f4 is the effective focal length of the fourth lens E4, and f is the effective focal length of the optical imaging system. By reasonably controlling the ratio range of the effective focal lengths of the first lens E1, the fourth lens E4, and the optical imaging system, the optical system can satisfy a large field angle while achieving a high imaging resolution. If it exceeds the upper limit of the relational expression, the refractive power of the first lens E1 and the fifth lens E5 is insufficient, and it is difficult for large-angle light rays to enter the optical system, which is not conducive to expanding the field angle range of the optical system. If it is lower than the lower limit of the relational expression, the refractive power of the first lens E1 and the second lens E2 is too strong, and strong astigmatism and chromatic aberration are easily generated, which is not conducive to high-resolution imaging characteristics.

[0041] Further, the optical system satisfies the following condition: -2.1 < (f4 - f3) / f3 < -0.7, where f3 is the effective focal length of the third lens E3 and f4 is the effective focal length of the fourth lens E4. By limiting the effective focal lengths of the third lens E3 and the fourth lens E4 of the optical imaging system within a reasonable range, the contributions of spherical aberration and coma of the third lens E3 and the fourth lens E4 can be effectively constrained, and after balancing, their sensitivity can be maintained at a reasonable level.

[0042] Further, the optical system satisfies the following condition: 1.7 < f123 / f < 2.8, where f is the effective focal length of the optical system and f123 is the effective combined focal length of the first lens E1, the second lens E2, and the third lens E3. By constraining the ratio of the combined focal length of the first lens E1, the second lens E2, and the third lens E3 to the effective focal length of the optical lens, the optical power distribution of the first lens E1, the second lens E2, and the third lens E3 can be made appropriate, enabling the third lens E3 to have diverse cooperations. Thus, while meeting the miniaturization design of the optical lens, the internal aberration of the optical lens can be balanced, which further helps to adjust the field curvature and astigmatism of the imaging edge of the optical lens and meet the imaging quality of the optical lens for the surrounding environment.

[0043] Furthermore, the optical system satisfies the following conditions: -2.2 < f1*f2 / (R2 + R3) < -0.8; where f1 is the effective focal length of the first lens E1, f2 is the effective focal length of the second lens E2, R2 is the radius of curvature of the image side of the first lens E1, and R3 is the radius of curvature of the object side of the second lens E2. By restricting the radius of curvature of the image side of the first lens E1 and the radius of curvature of the object side of the second lens E2, the optical powers of the first lens E1 and the second lens E2 are adjusted to avoid excessive concentration of the optical power on the second lens E2. At the same time, it helps to restrict the surface shapes of the image side of the first lens E1 and the object side of the second lens E2, avoiding excessive bending and affecting the processing manufacturability of the first lens E1 and the second lens E2. In addition, by satisfying the above relationship, on the basis of reducing third-order aberrations such as spherical aberration, coma, and field curvature, the correction of higher-order aberrations can be further enhanced, and the tolerance sensitivity of the optical lens can be reduced. When exceeding the lower limit of the above relationship, the optical power of the second lens E2 is too concentrated, resulting in excessive bending of the surface shape of the object side of the second lens E2, which is not conducive to the processing manufacturability of the second lens E2. When exceeding the upper limit of the above relationship, the optical power of the fourth lens E4 is insufficient, which is not conducive to the correction of the aberrations of the optical lens and affects the tolerance sensitivity of the optical lens.

[0044] Furthermore, the optical system satisfies the following conditions: 0.5 < f2 / R3 < 1.2, where f2 is the effective focal length of the second lens E2 and R3 is the radius of curvature of the object side of the second lens E2. By controlling the ratio of the radius of curvature of the object side of the second lens E2 to the effective focal length of the second lens E2, it is beneficial to reasonably control the bending degree of the second lens E2, enabling it to have better processing and forming characteristics. At the same time, it avoids excessive deflection of light when transmitting between lenses, reducing the processing difficulty of the optical lens group.

[0045] Furthermore, the optical system satisfies the following conditions: 0.4 < |R8| / R2 < 1.2, where R2 is the radius of curvature of the image side of the first lens E1 and R8 is the radius of curvature of the image side of the fourth lens E4. When the above conditional formula is satisfied, by reasonably controlling the ratio range of the radius of curvature of the image side of the first lens E1 to the radius of curvature of the image side of the fourth lens E4, it is beneficial to control the bending degrees of the first lens E1 and the fourth lens E4, provide a sufficiently large field angle for the imaging optical system, and at the same time facilitate the correction of the marginal aberrations of the imaging optical system, reduce the generation of astigmatism, and improve the imaging effect of the imaging optical system. When exceeding the upper limit of the above relationship, it is not conducive to the correction of the aberrations of the imaging optical system; when lower than the lower limit of the above relationship, the risk of ghost images appears, restricting the imaging performance of the imaging optical system.

[0046] Furthermore, the optical system satisfies the following conditions: 2.0 < (CT4 + CT5) / BFL < 2.4, where CT4 is the central thickness of the fourth lens E4 on the optical axis, CT5 is the central thickness of the fifth lens E5 on the optical axis, and BFL is the shortest distance from the image side of the fifth lens E5 to the imaging surface of the optical system in the optical axis direction. When the above condition formula is satisfied, by controlling the above back focal length within a reasonable range, the matching degree between the imaging screen and the electronic photosensitive chip is effectively ensured, and the matching of the imaging optical system and the electronic photosensitive chip is guaranteed; at the same time, by controlling the central thickness of the above lenses on the optical axis, the compactness of the system structure can be effectively improved, the total optical length of the imaging optical system can be reduced, the size of the optical system can be further reduced, and it can better develop in the direction of miniaturization. Moreover, it is beneficial to the molding and assembly of the fourth lens E4 and the fifth lens E5, reduces the manufacturing cost of the optical system, and also reduces the eccentricity sensitivity of the optical system, which is beneficial to ensuring the imaging quality of the optical system.

[0047] Furthermore, the optical system satisfies the following conditions: 5.0 < |DT52 - DT51 / DT42 - DT41| < 11.0; where DT41 is the maximum effective radius of the object side of the fourth lens E4, DT42 is the maximum effective radius of the image side of the fourth lens E4, DT51 is the maximum effective radius of the object side of the fifth lens E5, and DT52 is the maximum effective radius of the image side of the fifth lens E5. By limiting the maximum effective radii of the object sides and image sides of the fourth lens E4 and the fifth lens E5 within a reasonable range, the size of the lens can be reduced, the miniaturization of the lens can be satisfied, and the resolution can be improved.

[0048] Furthermore, the optical system satisfies the following conditions: -6.1 < DT52 / SAG10 < -3.6; where DT52 is the maximum effective radius of the image side of the fifth lens E5, and SAG10 is the distance parallel to the optical axis from the maximum effective clear aperture of the image side of the fifth lens E5 to the intersection of the image side of the fifth lens E5 and the optical axis. By making the optical system satisfy the above relationship formula, it is beneficial to prevent the surface shape of the image side of the fifth lens E5 from being too curved, thereby reducing the processing difficulty of the fifth lens E5; below the lower limit of the relationship formula, the maximum effective aperture of the image side of the fifth lens E5 is too small, which is not conducive to large-angle light rays entering the optical system and reduces the imaging range of the optical system; exceeding the upper limit of the relationship formula, the image side of the fifth lens E5 is too flat, and the risk of ghost images in the optical system is large.

[0049] Preferably, the optical system satisfies the following condition: 0.5<(SAG9-SAG10) / (SAG7+SAG8)<2.1; wherein, SAG7 is the distance from the maximum effective aperture of the object side surface of the fourth lens E4 to the intersection of the object side surface of the fourth lens E4 and the optical axis in the direction parallel to the optical axis, SAG8 is the distance from the maximum effective aperture of the image side surface of the fourth lens E4 to the intersection of the image side surface of the fourth lens E4 and the optical axis in the direction parallel to the optical axis, and SAG9 is the distance from the maximum effective aperture of the object side surface of the fifth lens E5 to the intersection of the image side surface of the fourth lens E4 and the optical axis in the direction parallel to the optical axis. SAG10 is the distance from the point of intersection of the object-side surface of the fifth lens element E5 and the optical axis, parallel to the optical axis. By limiting the range of the ratio of the sag heights of the object-side and image-side surfaces of the fourth lens element E4 and the fifth lens element E5, the shapes of the object-side and image-side surfaces of the fourth lens element E4 and the fifth lens element E5 can be constrained to correct the field curvature of the imaging optical lens, reduce the risk of ghost images, and thus improve the imaging quality of the optical lens. When this ratio exceeds the upper limit, the sag height of the image-side surface of the fifth lens element E5 is too large, resulting in excessive curvature of the image-side surface of the fifth lens element E5, which is detrimental to the manufacturing, molding, and assembly of the fifth lens element E5 and can easily lead to a decrease in the imaging quality of the optical lens.

[0050] Furthermore, the maximum effective radius DT11 of the object side of the first lens E1 is ≤1.78mm, the F number of the optical system is 2.2, the full field of view FOV of the optical system is >130, and the total optical length TTL is ≤6.8mm. This design can reduce the total optical length and effectively miniaturize the lens. The optical system configured in the present invention has the advantages of high pixels and large wide angles, a compact structure, and is easy to process and install. It increases the amount of light entering the optical system and achieves higher imaging quality. Through reasonable distribution of optical focal length and optimized selection of high-order aspheric parameters, it can achieve miniaturization while taking into account the light and ultra-wide-angle shooting functions.

[0051] Specifically, as a preferred embodiment of the present invention but not limiting, Figure 1-2As shown in Example 1, the lens includes, in order from the object side to the image side along the optical axis: a first lens E1, STO, a second lens E2, an third lens E3, a fourth lens E4, a fifth lens E5, an infrared filter E6, and an imaging surface S13. The first lens E1 has negative optical power, with its object-side surface S1 and image-side surface S2 being concave. The second lens E2 has positive optical power, with its object-side surface S3 and image-side surface S4 being convex. The third lens E3 has negative optical power, with its object-side surface S5 and image-side surface S6 being convex. The fourth lens E4 has positive optical power, with its object-side surface S7 and image-side surface S8 being convex. The fifth lens E5 has negative optical power, with its object-side surface S9 and image-side surface S10 being convex. The filter E6 has an object-side surface S11 and an image-side surface S12. Light from an object sequentially passes through surfaces S1 to S12 and is ultimately imaged on the imaging surface S13.

[0052] In this embodiment 1, the focal length f1 of the first lens element E1 is -3.23 mm, the focal length f2 of the second lens element E2 is 1.93 mm, the focal length f3 of the third lens element E3 is -3.78 mm, the focal length f4 of the fourth lens element E4 is 2.96 mm, the focal length f5 of the fifth lens element E5 is -3.58 mm, the lens focal length f is 2.35 mm, the total optical length TTL is 6.80 mm, the FOV is 130.00°, and the f / EPD is 2.20. The parameters of each lens are shown in Table 1:

[0053] Table 1: Basic parameters of the optical system of Example 1

[0054] Face number Surface type Curvature radius (mm) Thickness (mm) Material OBJ spherical surface endless endless S1 Q-type aspheric surface -16.9555 0.4807 1.54,55.77 S2 Q-type aspheric surface 1.9533 1.0254 STO spherical surface endless 0.0697 S3 Q-type aspheric surface 3.0557 1.0483 1.54,55.77 S4 Q-type aspheric surface -1.3827 0.0890 S5 Q-type aspheric surface 5.4387 0.3618 1.66,20.38 S6 Q-type aspheric surface 1.6770 0.1599 S7 Q-type aspheric surface 9.5524 1.0412 1.54,55.77 S8 Q-type aspheric surface -1.8348 0.8170 S9 Q-type aspheric surface 25.7915 0.7432 1.66,20.38 S10 Q-type aspheric surface 2.1585 0.4796 S11 spherical surface endless 0.2100 1.52,64.17 S12 spherical surface endless 0.2741 S13 spherical surface endless

[0055] In Table 1, the object side and image side of any lens of the first lens E1 to the fifth lens E5 are all Q-type aspherical surfaces. The surface shape of each aspherical lens can be defined by, but not limited to, the following aspherical formula:

[0056]

[0057] Where Z is the distance from the corresponding point on the aspheric surface to the plane tangent to the vertex of the surface, r is the radial coordinate of the aspheric surface, c is the curvature of the vertex of the aspheric surface, K is the conic coefficient, Am is the aspheric coefficient, rmax is the maximum radial radius coordinate, and u = r / rmax. Table 2 shows the conic coefficients and higher-order coefficients A4, A6, A8, A10, A12, A14, A16, A18, A20, A22, A24, A26, A28, and A30 of various aspheric surfaces that can be used in Example 1.

[0058] Table 2: Aspheric surface related values of the lens surface of Example 1

[0059] Surface number 1 2 3 4 5 K -8.85E+01 -2.12E+00 2.21E+00 -2.95E+00 -1.28E+00 A4 4.69E-01 2.88E-01 -1.29E-02 -1.03E-01 -2.39E-01 A6 -9.35E-02 4.94E-03 -4.28E-03 -2.41E-02 -1.38E-02 A8 1.08E-02 8.16E-04 -8.64E-04 -2.89E-03 4.60E-04 A10 -2.72E-03 -2.78E-04 -1.33E-04 -1.23E-03 3.34E-03 A12 1.06E-03 -1.23E-04 -1.26E-05 -1.47E-04 1.11E-03 A14 -1.81E-04 5.67E-05 4.15E-05 -7.46E-05 3.15E-04 A16 2.13E-05 3.76E-07 3.31E-05 -6.38E-06 -7.52E-05 A18 7.53E-06 2.06E-05 3.56E-05 1.56E-05 -3.20E-05 A20 -6.16E-06 5.00E-06 2.23E-05 2.08E-05 3.23E-05 A22 -2.79E-07 8.35E-06 1.91E-05 1.12E-05 4.60E-05 A24 -7.38E-06 -3.65E-06 1.52E-05 1.50E-05 4.13E-05 A26 1.73E-06 1.95E-07 1.35E-05 6.52E-06 1.69E-05 A28 3.24E-06 -5.60E-06 2.64E-06 2.59E-06 8.49E-06 A30 -1.13E-06 2.53E-06 -2.57E-06 -4.29E-06 -1.71E-06 Surface number 6 7 8 9 10 K -9.66E+00 -2.67E+01 -1.28E+00 -1.00E+00 -1.96E+01 A4 -1.31E-01 4.91E-02 6.15E-02 -8.94E-01 -1.14E+00 A6 -3.55E-03 1.59E-02 4.02E-02 5.61E-02 9.60E-02 A8 -1.88E-03 -2.79E-03 8.18E-03 4.91E-03 -1.77E-02 A10 1.80E-03 2.33E-04 1.10E-03 1.47E-02 2.58E-02 A12 4.53E-05 -2.87E-04 -9.62E-04 -6.28E-04 -4.02E-03 A14 4.25E-04 2.87E-04 -4.83E-04 -5.71E-04 -7.65E-04 A16 -5.28E-05 -5.38E-05 -6.08E-05 -7.91E-04 -1.96E-03 A18 1.96E-06 -3.93E-05 1.11E-05 0.00E+00 -1.40E-03 A20 -1.07E-05 4.42E-06 4.48E-05 -2.66E-05 -7.39E-04 A22 7.86E-06 1.77E-06 -1.47E-05 8.97E-05 -6.16E-04 A24 7.55E-06 2.42E-06 4.35E-06 -4.46E-05 -3.14E-04 A26 1.24E-06 1.63E-07 -1.25E-05 4.44E-06 -1.85E-04 A28 -9.00E-11 5.57E-07 9.97E-06 -2.34E-05 -7.38E-05 A30 -4.66E-07 -4.03E-07 -2.15E-06 9.17E-06 -2.38E-05

[0060] Figure 2 The following plots show the axial chromatic aberration, astigmatism, and distortion curves for the optical imaging lens of Example 1. Axial chromatic aberration indicates the deviation of light of different wavelengths from the focal point after passing through the lens; astigmatism indicates meridional and sagittal image curvature; and distortion indicates the magnitude of distortion at different image heights.

[0061] Specifically, as a preferred embodiment of the present invention but not limiting, Figure 3-4 As shown in Example 2, the lens includes, in order from the object side to the image side along the optical axis: a first lens E1, STO, a second lens E2, a third lens E3, a fourth lens E4, a fifth lens E5, an infrared filter E6, and an imaging surface S13. The first lens E1 has negative optical power, with its object-side surface S1 and image-side surface S2 being concave. The second lens E2 has positive optical power, with its object-side surface S3 and image-side surface S4 being convex. The third lens E3 has positive optical power, with its object-side surface S5 and image-side surface S6 being convex. The fourth lens E4 has positive optical power, with its object-side surface S7 and image-side surface S8 being convex. The fifth lens E5 has negative optical power, with its object-side surface S9 and image-side surface S10 being concave. The filter E6 has an object-side surface S11 and an image-side surface S12. Light from an object sequentially passes through surfaces S1 to S12 and is ultimately imaged on the imaging surface S13.

[0062] In this embodiment 2, the focal length f1 of the first lens element E1 is -3.19 mm, the focal length f2 of the second lens element E2 is 3.25 mm, the focal length f3 of the third lens element E3 is 16.11 mm, the focal length f4 of the fourth lens element E4 is 3.61 mm, the focal length f5 of the fifth lens element E5 is -3.09 mm, the lens focal length f is 2.44 mm, the total optical length TTL is 6.71 mm, the FOV is 135.12°, and the f / EPD is 2.20. The lens parameters are shown in Table 1:

[0063] Table 3: Basic parameters of the optical system of Example 2

[0064] Face number Surface type Curvature radius (mm) Thickness (mm) Material OBJ spherical surface endless endless S1 Q-type aspheric surface -11.4027 0.4807 1.77,49.50 S2 Q-type aspheric surface 2.0453 1.0254 STO spherical surface endless 0.0809 S3 Q-type aspheric surface 2.8740 1.0483 1.53,65.84 S4 Q-type aspheric surface -3.8546 0.1283 S5 Q-type aspheric surface 1.5345 0.3627 1.68,31.33 S6 Q-type aspheric surface 1.6105 0.1608 S7 Q-type aspheric surface 9.6496 0.9867 1.54,55.77 S8 Q-type aspheric surface -2.3354 0.8165 S9 Q-type aspheric surface -70.2234 0.6794 1.74,28.01 S10 Q-type aspheric surface 2.4083 0.4701 S11 spherical surface endless 0.2100 1.52,64.17 S12 spherical surface endless 0.2647 S13 spherical surface endless

[0065] In Table 3, the object side and image side of any lens of the first lens E1 to the fifth lens E5 are all Q-type aspherical surfaces. The surface shape of each aspherical lens can be defined by, but not limited to, the following aspherical surface formula:

[0066]

[0067] Where Z is the distance from the corresponding point on the aspheric surface to the plane tangent to the vertex of the surface, r is the radial coordinate of the aspheric surface, c is the curvature of the vertex of the aspheric surface, K is the conic coefficient, Am is the aspheric coefficient, rmax is the maximum radial radius coordinate, and u = r / rmax. Table 4 shows the conic coefficients and higher-order coefficients A4, A6, A8, A10, A12, A14, A16, A18, A20, A22, A24, A26, A28, and A30 of various aspheric surfaces that can be used in Example 2.

[0068] Table 4: Aspheric surface related values of the lens surface of Example 2

[0069] Surface number 1 2 3 4 5 K -3.22E+01 -3.77E+00 4.59E+00 1.08E+00 -5.78E+00 A4 4.66E-01 2.81E-01 -6.82E-03 -1.53E-01 -2.52E-01 A6 -9.57E-02 8.43E-03 -2.82E-03 1.20E-02 -3.45E-03 A8 1.14E-02 5.10E-04 -8.87E-04 -7.64E-03 -7.45E-03 A10 -3.37E-03 6.43E-05 -3.31E-05 1.29E-03 3.84E-03 A12 1.50E-03 -3.87E-04 -3.41E-05 -6.01E-04 -9.01E-05 A14 -2.38E-04 1.44E-04 1.13E-04 1.76E-04 6.60E-04 A16 8.71E-05 -7.08E-05 -8.54E-06 3.76E-05 8.28E-06 A18 -4.50E-05 9.43E-05 -1.23E-06 -6.85E-05 5.35E-05 A20 -8.75E-08 -6.89E-05 -3.38E-05 3.46E-07 -3.55E-05 A22 2.11E-05 8.23E-06 -2.59E-05 1.01E-06 2.35E-06 A24 -5.22E-05 -2.78E-05 2.95E-05 3.58E-05 -1.42E-05 A26 4.83E-06 -1.76E-05 3.06E-05 -2.48E-05 -1.24E-05 A28 -1.37E-05 -1.60E-06 1.95E-06 1.65E-05 -1.12E-05 A30 -1.35E-05 1.36E-05 -1.89E-06 -6.78E-06 6.27E-06 Surface number 6 7 8 9 10 K -6.53E+00 1.43E+01 -7.33E-01 1.83E+01 -2.63E+01 A4 -1.21E-01 6.39E-02 3.93E-02 -8.86E-01 -1.03E+00 A6 -9.89E-03 1.16E-02 3.60E-02 7.17E-02 1.30E-01 A8 -1.55E-03 -3.78E-03 7.17E-03 1.87E-02 -1.30E-02 A10 7.62E-04 -5.06E-04 1.82E-03 1.06E-02 1.84E-02 A12 -4.55E-05 -1.12E-04 -9.57E-04 -1.39E-03 -5.71E-03 A14 2.81E-04 1.86E-04 -4.96E-04 -2.15E-03 -1.64E-03 A16 2.34E-05 -3.78E-05 -1.04E-04 -3.37E-04 -2.89E-03 A18 9.42E-06 -2.52E-05 -4.07E-05 0.00E+00 -9.92E-04 A20 1.48E-05 9.01E-06 6.55E-05 4.09E-04 -8.84E-04 A22 1.95E-05 5.31E-06 -4.80E-05 -1.44E-04 -2.22E-04 A24 9.38E-06 3.93E-06 3.36E-06 -6.31E-05 -1.52E-04 A26 -1.32E-05 -1.98E-07 -1.35E-05 -1.20E-04 3.56E-04 A28 -1.23E-06 1.08E-06 9.61E-06 5.58E-05 7.69E-05 A30 8.67E-06 -6.50E-07 -1.62E-06 6.19E-06 2.02E-04

[0070] Figure 4 The following graph shows the axial chromatic aberration, astigmatism, and distortion curves for the optical imaging lens of Example 2. Axial chromatic aberration indicates the deviation of light of different wavelengths from the focal point after passing through the lens; astigmatism represents meridional and sagittal image curvature; and distortion indicates the magnitude of distortion at different image heights. The graph demonstrates that the optical imaging lens of Example 2 achieves excellent imaging quality.

[0071] Specifically, as a preferred embodiment of the present invention but not limiting, Figure 5-6 As shown in Example 3, the lens includes, in order from the object side to the image side along the optical axis: a first lens E1, STO, a second lens E2, a third lens E3, a fourth lens E4, a fifth lens E5, an infrared filter E6, and an imaging surface S13. The first lens E1 has negative optical power, with its object-side surface S1 being convex and its image-side surface S2 being concave. The second lens E2 has positive optical power, with its object-side surface S3 being convex and its image-side surface S4 being convex. The third lens E3 has negative optical power, with its object-side surface S5 being convex and its image-side surface S6 being concave. The fourth lens E4 has positive optical power, with its object-side surface S7 being concave and its image-side surface S8 being convex. The fifth lens E5 has negative optical power, with its object-side surface S9 being convex and its image-side surface S10 being concave. The filter E6 has an object-side surface S11 and an image-side surface S12. Light from an object sequentially passes through surfaces S1 to S12 and is ultimately imaged on the imaging surface S13.

[0072] In this embodiment 3, the focal length f1 of the first lens element E1 is -3.66 mm, the focal length f2 of the second lens element E2 is 1.93 mm, the focal length f3 of the third lens element E3 is -4.19 mm, the focal length f4 of the fourth lens element E4 is 3.32 mm, the focal length f5 of the fifth lens element E5 is -3.58 mm, the lens focal length f is 2.47 mm, the total optical length TTL is 6.80 mm, the FOV is 130.00°, and the f / EPD is 2.20. The lens parameters are shown in Table 1:

[0073] Table 5: Basic parameters of the optical system of Example 3

[0074] Face number Surface type Curvature radius (mm) Thickness (mm) Material OBJ spherical surface endless endless S1 Q-type aspheric surface 640.0000 0.4821 1.54,55.77 S2 Q-type aspheric surface 1.9597 1.0312 STO spherical surface endless 0.0743 S3 Q-type aspheric surface 3.0571 1.0484 1.54,55.77 S4 Q-type aspheric surface -1.3816 0.0876 S5 Q-type aspheric surface 5.4493 0.3615 1.66,20.38 S6 Q-type aspheric surface 1.7998 0.1660 S7 Q-type aspheric surface -73.2265 1.0384 1.54,55.77 S8 Q-type aspheric surface -1.7469 0.8158 S9 Q-type aspheric surface 24.9849 0.7374 1.66,20.38 S10 Q-type aspheric surface 2.1527 0.4756 S11 spherical surface endless 0.2100 1.52,64.17 S12 spherical surface endless 0.2702 S13 spherical surface endless

[0075] In Table 5, the object side and image side of any lens of the first lens E1 to the fifth lens E5 are all Q-type aspherical surfaces. The surface shape of each aspherical lens can be defined by, but not limited to, the following aspherical surface formula:

[0076]

[0077] Where Z is the distance from the corresponding point on the aspheric surface to the plane tangent to the vertex of the surface, r is the radial coordinate of the aspheric surface, c is the curvature of the vertex of the aspheric surface, K is the conic coefficient, Am is the aspheric coefficient, rmax is the maximum radial radius coordinate, and u = r / rmax. Table 6 shows the conic coefficients and higher-order coefficients A4, A6, A8, A10, A12, A14, A16, A18, A20, A22, A24, A26, A28, and A30 of various aspheric surfaces that can be used in Example 3.

[0078] Table 6: Aspheric surface related values of the lens surface of Example 3

[0079] Surface number 1 2 3 4 5 K 9.00E+01 -3.81E+00 1.85E+00 -2.57E+00 -3.09E+01 A4 4.24E-01 2.74E-01 -1.39E-02 -1.14E-01 -2.55E-01 A6 -8.29E-02 4.92E-03 -4.71E-03 -2.20E-02 -8.96E-03 A8 8.34E-03 1.71E-03 -1.05E-03 -4.79E-03 7.80E-04 A10 -2.08E-03 -4.31E-05 -2.50E-04 -1.06E-03 4.38E-03 A12 1.09E-03 4.73E-05 -8.87E-05 -5.26E-04 6.48E-04 A14 -2.52E-04 5.56E-05 -2.85E-05 -8.73E-05 1.74E-04 A16 6.95E-05 5.71E-06 -1.75E-05 -5.09E-05 -2.93E-04 A18 -3.25E-05 1.53E-05 -2.57E-06 2.59E-05 -1.03E-04 A20 1.86E-05 -1.43E-06 1.53E-06 3.57E-05 -5.44E-05 A22 -1.01E-05 1.17E-05 3.83E-06 1.06E-05 4.41E-06 A24 -1.78E-06 -4.67E-06 3.33E-06 4.90E-06 1.97E-05 A26 -7.80E-07 3.73E-06 4.57E-06 -1.42E-05 3.01E-05 A28 3.39E-06 -5.62E-06 9.53E-07 -1.12E-05 2.40E-05 A30 -1.04E-06 1.95E-06 -2.07E-06 -1.23E-05 1.04E-05 Surface number 6 7 8 9 10 K -1.07E+01 -9.00E+01 -9.32E-01 -7.81E+01 -1.46E+01 A4 -1.35E-01 7.12E-02 3.62E-02 -9.10E-01 -1.23E+00 A6 -2.36E-03 9.40E-03 3.26E-02 4.23E-02 6.44E-02 A8 -2.86E-03 -3.45E-03 8.97E-03 7.49E-03 -2.77E-03 A10 1.41E-03 -6.26E-04 1.21E-03 1.17E-02 2.42E-02 A12 -2.92E-04 -4.05E-04 -6.82E-04 9.90E-04 2.80E-03 A14 4.44E-04 2.36E-04 -5.08E-04 -2.30E-04 -1.48E-04 A16 -1.14E-04 -1.31E-04 -9.14E-05 -7.50E-04 -8.21E-04 A18 3.85E-05 -5.02E-05 1.51E-06 0.00E+00 -9.29E-04 A20 -1.47E-05 1.93E-05 3.79E-05 -5.47E-05 -6.52E-04 A22 3.67E-05 2.71E-05 -1.49E-05 8.40E-05 -4.77E-04 A24 -1.62E-06 -2.03E-06 3.90E-06 -3.03E-05 -3.14E-04 A26 7.48E-06 3.05E-06 -1.26E-05 1.33E-05 -1.99E-04 A28 -6.40E-06 2.94E-06 1.01E-05 -3.34E-05 -1.48E-04 A30 6.16E-07 -2.30E-06 -2.07E-06 1.32E-05 -4.58E-05

[0080] Figure 6 The following graph shows the axial chromatic aberration, astigmatism, and distortion curves for the optical imaging lens of Example 3. Axial chromatic aberration indicates the deviation of light of different wavelengths from the focal point after passing through the lens; astigmatism represents meridional and sagittal image curvature; and distortion indicates the magnitude of distortion at different image heights. The graph demonstrates that the optical imaging lens of Example 3 achieves excellent imaging quality.

[0081] Specifically, as a preferred embodiment of the present invention but not limiting, Figure 7-8 As shown in Example 4, along the optical axis, from the object side to the image side, the following are included: a first lens E1 having negative focal power, with its object-side surface S1 being concave and its image-side surface S2 being concave. A second lens E2 having positive focal power, with its object-side surface S3 being convex and its image-side surface S4 being convex. A third lens E3 having negative focal power, with its object-side surface S5 being concave and its image-side surface S6 being concave. A fourth lens E4 having positive focal power, with its object-side surface S7 being concave and its image-side surface S8 being convex. A fifth lens E5 having negative focal power, with its object-side surface S9 being convex and its image-side surface S10 being concave. A filter E6 having an object-side surface S11 and an image-side surface S12. Light from an object sequentially passes through surfaces S1 to S12 and is ultimately imaged on an imaging surface S13.

[0082] In this embodiment 4, the focal length f1 of the first lens element E1 is -3.40 mm, the focal length f2 of the second lens element E2 is 1.65 mm, the focal length f3 of the third lens element E3 is -2.69 mm, the focal length f4 of the fourth lens element E4 is 2.88 mm, the focal length f5 of the fifth lens element E5 is -3.58 mm, the lens focal length f is 2.32 mm, the total optical length TTL is 6.69 mm, the FOV is 130.00°, and the f / EPD is 2.20. The lens parameters are shown in Table 1:

[0083] Table 7: Basic parameters of the optical system of Example 4

[0084] Face number Surface type Curvature radius (mm) Thickness (mm) Material OBJ spherical surface endless endless S1 Q-type aspheric surface -4.2735 0.4821 1.54,55.77 S2 Q-type aspheric surface 3.3046 1.0312 STO spherical surface endless -0.0300 S3 Q-type aspheric surface 3.0571 1.0484 1.54,55.77 S4 Q-type aspheric surface -1.1001 0.0876 S5 Q-type aspheric surface -588.5410 0.3615 1.66,20.38 S6 Q-type aspheric surface 1.7998 0.1660 S7 Q-type aspheric surface -73.2265 1.0384 1.54,55.77 S8 Q-type aspheric surface -1.5205 0.8158 S9 Q-type aspheric surface 24.9849 0.7374 1.66,20.38 S10 Q-type aspheric surface 2.1527 0.4756 S11 spherical surface endless 0.2100 1.52,64.17 S12 spherical surface endless 0.2702 S13 spherical surface endless

[0085] In Table 7, the object side and image side of any lens of the first lens E1 to the fifth lens E5 are all Q-type aspherical surfaces. The surface shape of each aspherical lens can be defined by, but not limited to, the following aspherical formula:

[0086]

[0087] Where Z is the distance from the corresponding point on the aspheric surface to the plane tangent to the vertex of the surface, r is the radial coordinate of the aspheric surface, c is the curvature of the vertex of the aspheric surface, K is the conic coefficient, Am is the aspheric coefficient, rmax is the maximum radial radius coordinate, and u = r / rmax. Table 8 shows the conic coefficients and higher-order coefficients A4, A6, A8, A10, A12, A14, A16, A18, A20, A22, A24, A26, A28, and A30 of various aspheric surfaces that can be used in Example 4.

[0088] Table 8: Aspheric surface related values of the lens surface of Example 4

[0089] Surface number 1 2 3 4 5 K -1.85E+01 -1.46E+01 -2.65E+00 -2.55E+00 -9.00E+01 A4 3.96E-01 2.42E-01 -2.47E-02 -1.30E-01 -2.09E-01 A6 -6.80E-02 9.08E-04 -8.81E-03 -4.92E-02 -1.70E-02 A8 1.21E-02 2.11E-03 -1.56E-03 -4.50E-03 8.32E-03 A10 -3.28E-03 6.14E-05 3.11E-04 -4.59E-03 1.55E-03 A12 1.01E-03 3.26E-05 5.17E-04 1.89E-04 1.25E-03 A14 -2.78E-04 4.89E-05 2.71E-04 -2.03E-04 -4.84E-04 A16 7.45E-05 -6.30E-06 -7.82E-05 3.31E-04 -1.89E-04 A18 -1.87E-05 8.65E-06 -2.87E-04 4.26E-06 -2.58E-04 A20 1.13E-05 -1.53E-06 -3.47E-04 -1.10E-05 -4.86E-05 A22 -3.73E-06 5.88E-06 -2.82E-04 -1.33E-04 -3.71E-05 A24 -1.14E-06 -1.48E-06 -1.80E-04 -1.12E-04 -7.92E-06 A26 -3.36E-06 2.36E-06 -8.48E-05 -9.58E-05 -2.25E-05 A28 3.55E-06 -4.29E-06 -2.81E-05 -4.49E-05 -1.31E-05 A30 -8.13E-07 1.51E-06 -3.01E-06 -2.08E-05 -6.16E-06 Surface number 6 7 8 9 10 K -9.70E+00 8.90E+01 -9.60E-01 3.15E+01 -6.44E+00 A4 -1.21E-01 7.54E-02 4.05E-02 -7.01E-01 -1.06E+00 A6 5.44E-03 9.12E-04 8.99E-03 -4.80E-02 6.68E-02 A8 2.43E-04 2.44E-03 6.86E-03 -1.63E-02 -2.83E-02 A10 8.28E-04 -4.15E-04 3.97E-04 -4.65E-03 5.20E-04 A12 -3.56E-05 -7.20E-05 -5.79E-05 -1.07E-03 7.31E-05 A14 3.69E-04 3.64E-04 -3.70E-04 -7.05E-04 -9.39E-04 A16 5.65E-05 9.43E-05 1.70E-05 -3.63E-05 7.98E-04 A18 -7.01E-05 -2.08E-04 -2.01E-05 0.00E+00 -4.73E-04 A20 -1.24E-04 -1.44E-04 5.59E-05 1.91E-05 3.25E-04 A22 -5.76E-05 -4.84E-05 2.79E-06 -6.35E-05 -1.79E-04 A24 -1.65E-05 2.50E-05 1.90E-05 -7.96E-05 1.67E-04 A26 9.85E-06 1.94E-05 -1.02E-05 -8.70E-05 -6.92E-05 A28 2.18E-06 9.45E-06 7.46E-06 -7.90E-05 1.16E-04 A30 1.07E-06 -4.04E-06 -8.49E-06 -1.22E-05 -7.62E-05

[0090] Figure 8 The following graph shows the axial chromatic aberration, astigmatism, and distortion curves for the optical imaging lens of Example 4. Axial chromatic aberration indicates the deviation of light of different wavelengths from the focal point after passing through the lens; astigmatism represents meridional and sagittal image curvature; and distortion indicates the magnitude of distortion at different image heights. The graph demonstrates that the optical imaging lens of Example 4 achieves excellent imaging quality.

[0091] Furthermore, in Examples 1-4, the basic data are shown in Table 9, and each conditional formula satisfies Table 10:

[0092] Table 9: Basic data of Examples 1-4

[0093] Basic data Example 1 Example 2 Example 3 Example 4 f1(mm) -3.23 -3.19 -3.66 -3.40 f2(mm) 1.93 3.25 1.93 1.65 f3(mm) -3.78 16.11 -4.19 -2.69 f4(mm) 2.96 3.61 3.32 2.88 f5(mm) -3.58 -3.09 -3.58 -3.58 f(mm) 2.35 2.44 2.47 2.32 TTL(mm) 6.80 6.71 6.80 6.69 FOV(°) 130.00 135.12 130.00 130.00 f / EPD 2.20 2.20 2.20 2.20

[0094] Table 10: Conditions of each conditional formula in Examples 1-4

[0095] Conditional expression Example 1 Example 2 Example 3 Example 4 CT4 1.04 0.99 1.04 1.04 CT5 0.74 0.68 0.74 0.74 BFL 0.89 0.88 0.86 0.80 R2 1.95 2.05 1.96 3.30 R3 3.06 2.87 3.06 3.06 R8 -1.83 -2.34 -1.75 -1.52 f123 6.57 4.27 4.92 5.94 DT11 1.73 1.63 1.74 1.78 DT41 1.39 1.41 1.38 1.28 DT42 1.45 1.35 1.50 1.39 DT51 1.59 1.61 1.63 1.53 DT52 2.30 2.09 2.33 2.39 IamgH 3.10 3.10 3.10 3.10 SAG7 0.18 0.17 0.08 0.06 SAG8 -0.35 -0.32 -0.47 -0.57 SAG9 -0.82 -0.65 -0.90 -0.68 SAG10 -0.56 -0.34 -0.64 -0.42 FOV / (DT11*TTL / IamgH) 34.19 38.29 34.06 33.83 f1*f4 / f -4.07 -4.72 -4.92 -4.22 (f4-f3) / f3 -1.78 -0.78 -1.79 -2.07 f123 / f 2.79 1.75 1.99 2.56 |R8| / R2 0.94 1.14 0.89 0.46 f1*f2 / (R2+R3) -1.25 -2.11 -1.41 -0.88 F2 / R3 0.63 1.13 0.63 0.54 (CT4+CT5) / BFL 2.09 2.04 2.16 2.31 |DT52-DT51 / DT42-DT41| 10.69 7.78 5.69 8.08 DT52 / SAG10 -4.07 -6.06 -3.64 -5.75 (SAG9-SAG10) / (SAG7+SAG8) 1.50 2.02 0.68 0.51

[0096] The embodiment of the present invention discloses an ultra-wide-angle, small-head, lightweight optical system, which is mainly composed of 5 lenses. Through the reasonable distribution of optical focal length and the optimized selection of high-order aspheric parameters, it can meet the market demand for optical lenses with a small head and lightness on the basis of satisfying the ultra-wide angle of the optical lens. The optical system configured by the present invention has the advantages of ultra-wide angle, small head, and lightness, has a compact structure, is easy to process and install, and at the same time, has good imaging resolution.

[0097] The above descriptions are provided in conjunction with specific content to provide one or more embodiments, and the specific implementation of the present invention is not limited to these descriptions. Any similarity or similarity with the methods, structures, etc. of the present invention, or any technical deduction or substitution based on the concept of the present invention, shall be considered within the scope of protection of the present invention.

Claims

1. An ultra-wide-angle, small-head, lightweight optical system, comprising, along the optical axis from the object plane to the image plane, a first lens, an aperture, a second lens, a third lens, a fourth lens, and a fifth lens, characterized by: The image side surface of the first lens is concave and has negative optical power; The object-side surface and image-side surface of the second lens are convex, and its optical power is positive; The image side surface of the third lens is concave and has optical power; The object side surface of the fourth lens is convex and has positive optical power; The object-side surface and image-side surface of the fifth lens are concave, and its optical power is negative; The optical system meets the following conditions: 33° / mm < FOV / (DT11*TTL / ImgH) < 39° / mm; Wherein, FOV is the maximum field of view of the optical system, DT11 is the maximum effective radius of the object side of the first lens, TTL is the axial distance from the object side of the first lens to the imaging surface, and ImgH is half of the diagonal length of the effective pixel area on the imaging surface.

2. The ultra-wide-angle, small-head, and thin optical system according to claim 1, characterized in that: The optical system meets the following conditions: -5mm < f1*f4 / f < -4mm; -2.1 < (f4-f3) / f3 < -0.7; Wherein, f1 is the effective focal length of the first lens, f3 is the effective focal length of the third lens, f4 is the effective focal length of the fourth lens, and f is the effective focal length of the optical system.

3. The ultra-wide-angle, small-head, and thin optical system according to claim 1, characterized in that: The optical system meets the following conditions: 1.7 < f123 / f < 2.8; Wherein, f is the effective focal length of the optical system, and f123 is the effective combined focal length of the first lens, the second lens, and the third lens.

4. The ultra-wide-angle, small-head, and thin optical system according to claim 1 is characterized in that: The optical system meets the following conditions: -2.2mm< f1*f2 / (R2+R3) < -0.8mm; 0.5 < f2 / R3 <1.2; Where f1 is the effective focal length of the first lens, f2 is the effective focal length of the second lens, R2 is the radius of curvature of the image side of the first lens, and R3 is the radius of curvature of the object side of the second lens.

5. The ultra-wide-angle, small-head, and thin optical system according to any one of claims 1 to 4, characterized in that: The optical system meets the following conditions: 0.4 < |R8| / R2 < 1.2; Wherein, R2 is the curvature radius of the image side surface of the first lens, and R8 is the curvature radius of the image side surface of the fourth lens.

6. The ultra-wide-angle, small-head, and thin optical system according to any one of claims 1 to 4, characterized in that: The optical system meets the following conditions: 2.0 < (CT4+CT5) / BFL < 2.4; Wherein, CT4 is the center thickness of the fourth lens on the optical axis, CT5 is the center thickness of the fifth lens on the optical axis, and BFL is the shortest distance from the image side of the fifth lens to the imaging plane of the optical system in the optical axis direction.

7. The ultra-wide-angle, small-head, and thin optical system according to any one of claims 1 to 4, characterized in that: The optical system meets the following conditions: 5.0 < |DT52-DT51 / DT42-DT41| < 11.0; Among them, DT41 is the maximum effective radius of the object side of the fourth lens, DT42 is the maximum effective radius of the image side of the fourth lens, DT51 is the maximum effective radius of the object side of the fifth lens, and DT52 is the maximum effective radius of the image side of the fifth lens.

8. The ultra-wide-angle, small-head, and thin optical system according to any one of claims 1 to 4, characterized in that: The optical system meets the following conditions: 0.5 < (SAG9-SAG10) / (SAG7+SAG8) < 2.1; Among them, SAG7 is the distance from the maximum effective aperture of the objective side of the fourth lens to the intersection of the objective side of the fourth lens and the optical axis in the direction parallel to the optical axis, SAG8 is the distance from the maximum effective aperture of the image side of the fourth lens to the intersection of the image side of the fourth lens and the optical axis in the direction parallel to the optical axis, SAG9 is the distance from the maximum effective aperture of the objective side of the fifth lens to the intersection of the objective side of the fifth lens and the optical axis in the direction parallel to the optical axis, and SAG10 is the distance from the maximum effective aperture of the image side of the fifth lens to the intersection of the image side of the fifth lens and the optical axis in the direction parallel to the optical axis.

9. The ultra-wide-angle, small-head, and thin optical system according to any one of claims 1 to 4, characterized in that: The maximum effective radius DT11 of the object side of the first lens is ≤ 1.78 mm; and / or The F number of the optical system is 2.

2.

10. The ultra-wide-angle, small-head, and lightweight optical system according to any one of claims 1 to 4, characterized in that: The full field of view (FOV) and total optical length (TTL) of the optical system meet the following requirements: FOV>130°, TTL≤6.8 mm.

Images