Wide-angle prime lens

Abstract

The invention provides a wide-angle prime lens, and relates to the technical field of optical lenses. The wide-angle prime lens provided by the embodiment of the invention comprises a first lens, a second lens, a third lens, a fourth lens, a fifth lens, a sixth lens, a seventh lens, an eighth lens, a ninth lens and a tenth lens which are sequentially arranged from an object space to an image space along an optical axis, the fourth lens, the fifth lens and the eighth lens have positive focal power, and the seventh lens has negative focal power; the wide-angle prime lens further comprises a diaphragm, and the diaphragm is located between the fourth lens and the fifth lens. The embodiment of the invention provides a wide-angle prime lens, so as to realize the wide-angle prime lens with small aperture and high image quality.

Description

Technical Field

[0001] The present invention relates to the technical field of optical lenses, and particularly to a wide-angle fixed-focus lens. Background Art

[0002] With the development of technology, the application scope of lenses is becoming more and more extensive. Accordingly, people's performance requirements for lenses are also becoming more diverse. Existing lenses generally have a small field of view angle, and multiple lenses are often required to capture the required range, which greatly increases the production cost. Summary of the Invention

[0003] An embodiment of the present invention provides a wide-angle fixed-focus lens to achieve a wide-angle fixed-focus lens with a small aperture and high image quality.

[0004] An embodiment of the present invention provides a wide-angle fixed-focus lens, including a first lens, a second lens, a third lens, a fourth lens, a fifth lens, a sixth lens, a seventh lens, an eighth lens, a ninth lens, and a tenth lens arranged in sequence from the object side to the image side along the optical axis;

[0005] The fourth lens, the fifth lens, and the eighth lens have positive optical powers, and the seventh lens has a negative optical power;

[0006] The wide-angle fixed-focus lens further includes a diaphragm, and the diaphragm is located between the fourth lens and the fifth lens.

[0007] Optionally, the sixth lens and the tenth lens have positive optical powers;

[0008] The first lens, the second lens, the third lens, and the ninth lens have negative optical powers.

[0009] Optionally, the fourth lens, the fifth lens, the seventh lens, the ninth lens, and the tenth lens are glass aspherical lenses.

[0010] Optionally, the fourth lens is a biconvex lens, the fifth lens is a biconvex lens, and the seventh lens is a biconcave lens;

[0011] The object side surface of the ninth lens is recessed toward the object side, and the image side surface of the ninth lens is convex toward the image side; the tenth lens is a biconvex lens.

[0012] Optionally, the radius of curvature of the object side surface of the first lens is L1R1, the radius of curvature of the image side surface of the first lens is L1R2, the focal length of the first lens is F1, the effective focal length of the wide-angle fixed-focus lens is F, and the refractive index of the first lens is Nd1, satisfying:

[0013] 6.110 ≤ L1R1 / L1R2 ≤ 7.533;

[0014] -1.590 ≤ F1 / F ≤ -1.044;

[0015] 1.80 ≤ Nd1 ≤ 1.93.

[0016] Optionally, the focal length of the fifth lens is F5, the Abbe number of the fifth lens is Vd5, and the effective focal length of the wide-angle fixed-focus lens is F, satisfying:

[0017] 1.669 ≤ F5 / F ≤ 2.884;

[0018] 75.00 ≤ Vd5 ≤ 96.00.

[0019] Optionally, the maximum lens diameter of the first lens is ΦL1, the total optical length of the wide-angle fixed-focus lens is TTL, the maximum imaging image height of the wide-angle fixed-focus lens is IH, and the radius of curvature of the object side of the first lens is L1R1, satisfying:

[0020] 0.000 ≤ ΦL1 / TTL ≤ 0.074;

[0021] 0.000 ≤ (ΦL1 × TTL) / IH ≤ 0.010;

[0022] 15.232 ≤ L1R1 / ΦL1 ≤ 90.006.

[0023] Optionally, the total optical length of the wide-angle fixed-focus lens is TTL, the effective focal length of the wide-angle fixed-focus lens is F, and the back focal length of the wide-angle fixed-focus lens is BFL, satisfying:

[0024] 0.051 ≤ BFL / TTL ≤ 0.075;

[0025] 0.125 ≤ F / TTL ≤ 0.216.

[0026] Optionally, the focal length of the ninth lens is F9, the focal length of the tenth lens is F10, and the effective focal length of the wide-angle fixed-focus lens is F, satisfying:

[0027] 1.642 ≤ F10 / F ≤ 2.045;

[0028] -2.733 ≤ F9 / F ≤ -1.391;

[0029] -1.096 ≤ F10 / F9 ≤ -0.705.

[0030] Optionally, the aperture of the wide-angle fixed-focus lens is FNO, and the field of view of the wide-angle fixed-focus lens is FOV, satisfying:

[0031] FNO ≥ 2.85; and / or, FOV ≤ 170°.

[0032] In the wide-angle fixed-focus lens provided by the embodiment of the present invention, through the reasonable matching of the optical powers of the fourth lens, the fifth lens, the seventh lens and the eighth lens, small aperture, large field angle and high image quality can be achieved, while taking into account a large image plane (the imaging target plane can reach 1"). The aperture stop is placed between the fourth lens with positive optical power and the fifth lens with positive optical power, so that the higher-order aberrations of the wide-angle fixed-focus lens are controlled at the front end of the wide-angle fixed-focus lens, and the light transmission of the wide-angle fixed-focus lens is improved. Description of the Drawings

[0033] Figure 1 It is a schematic structural diagram of the wide-angle fixed-focus lens provided by Embodiment 1 of the present invention;

[0034] Figure 2 It is a field curvature diagram of the wide-angle fixed-focus lens provided by Embodiment 1 of the present invention;

[0035] Figure 3 It is a distortion diagram of the wide-angle fixed-focus lens provided by Embodiment 1 of the present invention;

[0036] Figures 4 - 9 It is a fan diagram of the wide-angle fixed-focus lens provided by Embodiment 1 of the present invention;

[0037] Figure 10 It is a lateral chromatic aberration diagram of the wide-angle fixed-focus lens provided by Embodiment 1 of the present invention;

[0038] Figure 11 It is an axial aberration diagram of the wide-angle fixed-focus lens provided by Embodiment 1 of the present invention;

[0039] Figure 12 It is a schematic structural diagram of the wide-angle fixed-focus lens provided by Embodiment 2 of the present invention;

[0040] Figure 13 It is a field curvature diagram of the wide-angle fixed-focus lens provided by Embodiment 2 of the present invention;

[0041] Figure 14 It is a distortion diagram of the wide-angle fixed-focus lens provided by Embodiment 2 of the present invention;

[0042] Figures 15 - 20 It is a fan diagram of the wide-angle fixed-focus lens provided by Embodiment 2 of the present invention;

[0043] Figure 21 It is a lateral chromatic aberration diagram of the wide-angle fixed-focus lens provided by Embodiment 2 of the present invention;

[0044] Figure 22 It is an axial aberration diagram of the wide-angle fixed-focus lens provided by Embodiment 2 of the present invention;

[0045] Figure 23 It is a schematic structural diagram of the wide-angle fixed-focus lens provided by Embodiment 3 of the present invention;

[0046] Figure 24 It is the field curvature diagram of the wide-angle fixed-focus lens provided in Embodiment 3 of the present invention;

[0047] Figure 25 It is the distortion diagram of the wide-angle fixed-focus lens provided in Embodiment 3 of the present invention;

[0048] Figures 26 - 31 It is the light fan diagram of the wide-angle fixed-focus lens provided in Embodiment 3 of the present invention;

[0049] Figure 32 It is the lateral chromatic aberration diagram of the wide-angle fixed-focus lens provided in Embodiment 3 of the present invention;

[0050] Figure 33 It is the axial aberration diagram of the wide-angle fixed-focus lens provided in Embodiment 3 of the present invention. Detailed implementation manners

[0051] The present invention will be further described in detail below with reference to the drawings and embodiments. It can be understood that the specific embodiments described herein are only used to explain the present invention, rather than limiting the present invention. Additionally, it should be noted that for the convenience of description, only the parts related to the present invention rather than all the structures are shown in the drawings.

[0052] Embodiment 1

[0053] Figure 1 It is the structural schematic diagram of the wide-angle fixed-focus lens provided in Embodiment 1 of the present invention. Refer to Figure 1 , the wide-angle fixed-focus lens includes a first lens L1, a second lens L2, a third lens L3, a fourth lens L4, a fifth lens L5, a sixth lens L6, a seventh lens L7, an eighth lens L8, a ninth lens L9, and a tenth lens L10 arranged in sequence along the optical axis from the object side to the image side; the fourth lens L4, the fifth lens L5, and the eighth lens L8 have positive optical powers, and the seventh lens L7 has negative optical power. The wide-angle fixed-focus lens further includes a stop STO, and the stop STO is located between the fourth lens L4 and the fifth lens L5.

[0054] In the wide-angle fixed-focus lens provided in the embodiment of the present invention, through the reasonable matching of the optical powers of the fourth lens L4, the fifth lens L5, the seventh lens L7, and the eighth lens L8, small aperture, large field of view angle, and high image quality can be achieved, while taking into account a large image plane (the imaging target plane can reach 1″). The stop STO is placed between the fourth lens L4 with positive optical power and the fifth lens L5 with positive optical power, so that the higher-order aberrations of the wide-angle fixed-focus lens are controlled at the front end of the wide-angle fixed-focus lens, and the light transmittance of the wide-angle fixed-focus lens is improved.

[0055] The wide-angle fixed-focus lens provided by the embodiment of the present invention can achieve clear imaging in the wavelength range of 436nm to 870nm under a 1″ image plane, with a small aperture, higher image quality, and an imaging range of 150° to 170°, meeting the usage requirements in more cases.

[0056] Optionally, referring to Figure 1 , the sixth lens L6 and the tenth lens L10 have positive optical powers; the first lens L1, the second lens L2, the third lens L3, and the ninth lens L9 have negative optical powers.

[0057] In the wide-angle fixed-focus lens, the lenses are arranged in a negative-negative-negative-positive-positive-positive-negative-positive-negative-positive combination to reasonably distribute the optical powers of the lenses, making the light propagation in the wide-angle fixed-focus lens more stable, preventing excessive deflection of light on the surface of a certain lens, thereby avoiding the introduction of larger aberrations. While ensuring a small aperture and low chromatic aberration, it further corrects higher-order aberrations and controls distortion, achieving higher imaging quality.

[0058] Optionally, referring to Figure 1 , the fourth lens L4, the fifth lens L5, the seventh lens L7, the ninth lens L9, and the tenth lens L10 are glass aspherical lenses. The use of aspherical surfaces can more easily correct higher-order aberrations.

[0059] Exemplarily, the first lens L1, the second lens L2, the third lens L3, the sixth lens L6, and the eighth lens L8 are glass spherical lenses. In the embodiment of the present invention, a combination of 5 glass spherical lenses and 5 glass aspherical lenses is used to achieve a wide-angle fixed-focus lens with a small aperture and high image quality.

[0060] Optionally, referring to Figure 1 , the fourth lens L4 is a biconvex lens. The object side of the fourth lens L4 bulges towards the object side, and the image side of the fourth lens L4 bulges towards the image side. The fourth lens L4 is a convex-convex lens. The fifth lens L5 is a biconvex lens. The object side of the fifth lens L5 bulges towards the object side, and the image side of the fifth lens L5 bulges towards the image side. The fifth lens L5 is a convex-convex lens. The seventh lens L7 is a biconcave lens; the object side of the seventh lens L7 is concave towards the object side, and the image side of the seventh lens L7 is concave towards the image side. The seventh lens L7 is a concave-concave lens. The object side of the ninth lens L9 is concave towards the object side, and the image side of the ninth lens L9 bulges towards the image side; the ninth lens L9 is a concave-convex lens. The tenth lens L10 is a biconvex lens. The object side of the tenth lens L10 bulges towards the object side, and the image side of the tenth lens L10 bulges towards the image side. The tenth lens L10 is a convex-convex lens.

[0061] Exemplarily, the first lens L1 is a convex-concave spherical glass lens; the second lens L2 is a convex-concave spherical glass lens; the third lens L3 is a concave-convex spherical glass lens; the fourth lens L4 is a convex-convex aspherical glass lens; the fifth lens L5 is a convex-convex aspherical glass lens; the sixth lens L6 is a convex-convex spherical glass lens; the seventh lens L7 is a concave-concave aspherical glass lens; the eighth lens L8 is a convex-convex spherical glass lens; the ninth lens L9 is a concave-convex aspherical glass lens; the tenth lens L10 is a convex-convex aspherical glass lens.

[0062] Optionally, referring to Figure 1 , the radius of curvature of the object side of the first lens L1 is L1R1, the radius of curvature of the image side of the first lens L1 is L1R2, the focal length of the first lens L1 is F1, the effective focal length of the wide-angle fixed-focus lens is F, and the refractive index of the first lens L1 is Nd1, satisfying: 6.110 ≤ L1R1 / L1R2 ≤ 7.533; -1.590 ≤ F1 / F ≤ -1.044; 1.80 ≤ Nd1 ≤ 1.93. The first lens L1 has a light-gathering effect. By restricting the focal length and refractive index of the first lens L1, the light trend of the wide-angle fixed-focus lens can be made gentle, which is beneficial for the wide-angle fixed-focus lens to achieve large-field imaging, so that the maximum field angle of the wide-angle fixed-focus lens can reach 170°. In addition, the first lens L1 uses a high-refractive-index material, which helps to correct high-order chromatic aberration and can also improve the imaging quality of the wide-angle fixed-focus lens, enabling different colors of light to be better focused on the same plane, thereby making the color reproduction of the captured image more accurate and the image clearer and sharper.

[0063] Optionally, referring to Figure 1 , the focal length of the fifth lens L5 is F5, the Abbe number of the fifth lens L5 is Vd5, and the effective focal length of the wide-angle fixed-focus lens is F, satisfying: 1.669 ≤ F5 / F ≤ 2.884; 75.00 ≤ Vd5 ≤ 96.00. Thus, the high-order chromatic aberration of the wide-angle fixed-focus lens can be effectively corrected, which is beneficial for achieving higher image quality. The fifth lens L5 is located behind the aperture STO, and the light enters the fifth lens L5 after passing through the aperture STO. The fifth lens L5 is a lens with a high Abbe number and can effectively reduce chromatic aberration. When the wide-angle fixed-focus lens forms an image, chromatic dispersion will cause colored fringes in the image, resulting in unclear images. The fifth lens L5 with a high Abbe number can focus different colors of light more on the same point, making the imaging color reproduction more accurate, improving the image quality, and making the details of the monitoring image clearer.

[0064] Optionally, referring to Figure 1, the maximum lens diameter of the first lens L1 is ΦL1, the overall optical length of the wide-angle fixed-focus lens is TTL, the maximum imaging image height of the wide-angle fixed-focus lens is IH, and the radius of curvature of the object side surface of the first lens L1 is L1R1, satisfying: 0.000 ≤ ΦL1 / TTL ≤ 0.074; 0.000 ≤ (ΦL1 × TTL) / IH ≤ 0.010; 15.232 ≤ L1R1 / ΦL1 ≤ 90.006. The first lens L1 can gently collect object-side light into the wide-angle fixed-focus lens, can correct high-order aberrations to a great extent, and is also conducive to achieving higher image quality and ensuring a smaller volume under the imaging conditions of the wide-angle fixed-focus lens at wide angles.

[0065] Optionally, referring to Figure 1 , the overall optical length of the wide-angle fixed-focus lens is TTL, the effective focal length of the wide-angle fixed-focus lens is F, and the optical back focal length of the wide-angle fixed-focus lens is BFL, satisfying: 0.051 ≤ BFL / TTL ≤ 0.075; 0.125 ≤ F / TTL ≤ 0.216. It is conducive to realizing the characteristic of a short back focal length on the basis of miniaturization. It is not only conducive to the assembly of the module, but also can meet the large image plane and high-quality imaging quality in the wide-angle fixed-focus lens, and at the same time ensure sufficient edge field angle of view of the large image plane imaging system and improve the image plane brightness.

[0066] Optionally, referring to Figure 1 , the focal length of the ninth lens L9 is F9, the focal length of the tenth lens L10 is F10, and the effective focal length of the wide-angle fixed-focus lens is F, satisfying: 1.642 ≤ F10 / F ≤ 2.045; -2.733 ≤ F9 / F ≤ -1.391; -1.096 ≤ F10 / F9 ≤ -0.705. In this way, the high-order aberrations of the wide-angle fixed-focus lens can be corrected. The tenth lens L10 has a positive optical power, and the ninth lens L9 has a negative optical power. The combination of one positive and one negative can compensate for the aberrations in the wide-angle fixed-focus lens to a certain extent, thereby balancing the high-order aberrations of the wide-angle fixed-focus lens and making the imaging clearer, more real, and the color reproduction more accurate.

[0067] Optionally, the aperture of the wide-angle fixed-focus lens is FNO, and the field angle of view of the wide-angle fixed-focus lens is FOV, satisfying: FNO ≥ 2.85; and / or, FOV ≤ 170°. Thus, the wide-angle fixed-focus lens realizes a small aperture and a large field angle of view. The aperture represents the light-passing aperture of the lens. The larger the aperture, the larger the aperture of the lens, and the more light enters the lens per unit time. The larger the FNO number, the smaller the aperture.

[0068] Exemplarily, referring to Figure 1 , the wide-angle fixed-focus lens further includes a flat glass CG, and the flat glass CG is located on the side of the tenth lens L10 away from the first lens L1. The flat glass CG is located on the image-side surface side of the tenth lens L10. After the flat glass CG, the image plane is shown.

[0069] Table 1 A set of design values of the wide-angle fixed-focus lens in the first embodiment

[0070] Surface number Surface type Radius of curvature Thickness Refractive index Abbe number 1 Standard surface 34.6627 1.4600 1.90 47.55 2 Standard surface 5.2601 2.2319 3 Standard surface 13.5467 0.7542 1.76 88.56 4 Aspherical surface 7.2553 2.9532 5 Aspherical surface -6.8066 0.9506 1.80 37.57 6 Standard surface -13.9856 0.0716 7 Aspherical surface 15.7734 2.9393 1.85 43.84 8 Aspherical surface -8.4111 1.7143 9 Standard surface INF 1.5482 10 STO INF 0.0476 11 Aspherical surface 14.3611 1.4988 1.50 95.23 12 Aspherical surface -10.2946 0.1455 13 Standard surface -226.7515 1.6488 1.50 88.88 14 Standard surface -5.7181 0.0764 15 Aspherical surface -14.5350 0.8701 1.69 29.18 16 Aspherical surface 5.2871 0.7747 17 Standard surface 13.0948 2.7033 1.50 51.68 18 Standard surface -7.9711 0.4540 19 Aspherical surface -4.5610 0.6497 1.67 47.09 20 Aspherical surface -11.8237 3.5298 21 Aspherical surface 8.6917 3.3562 1.73 95.10 22 Aspherical surface -29.4736 0.5489 23 Standard surface INF 0.6000 1.52 64.17 24 Standard surface INF 0.7525 25 IMX INF -

[0071] Table 1 shows a set of design values of the wide-angle fixed-focus lens in the first embodiment. The specific numerical values can be adjusted according to product requirements, which is not a limitation to the embodiments of the present invention. The wide-angle fixed-focus lens shown in Table 1 can be Figure 1 as shown in. Generally, a lens includes two surfaces, and each surface is a refractive surface. The surface numbers in Table 1 are numbered according to the surfaces of each lens. Among them, surface number 1 represents the front surface (i.e., the object side) of the first lens L1, surface number 2 represents the rear surface (i.e., the image side) of the first lens L1, and so on, which will not be elaborated here. The virtual surface corresponding to surface number 9 is Figure 1 shown as the vertical line between the fourth lens L4 and the aperture STO in. The STO in the surface type column represents the aperture. The IMX in the surface type column represents the image plane. The radius of curvature represents the degree of curvature of the lens surface. A positive radius of curvature value indicates that the center of curvature is on the side of the surface close to the image side, that is, a positive value represents that the surface bends towards the image side; a negative radius of curvature value represents that the center of curvature is on the side of the surface far from the image side, that is, a negative value represents that the surface bends towards the object side. INF in the radius of curvature column represents that the surface is a plane and the radius of curvature is infinite. The value in the thickness column represents the central axial distance from the current surface to the next surface. The refractive index column represents the refractive index of the medium between the current surface and the next surface, representing the ability of the material between the current surface and the next surface to deflect light. The space in the refractive index column is the refractive index of air, and the refractive index of air is 1. The Abbe number represents the dispersion characteristic of the material between the current surface and the next surface to light, and the space represents that the current position is air.

[0072] Table 2 A set of design values of the aspherical coefficients of the lenses in the wide-angle fixed-focus lens in the first embodiment

[0073] Surface number K a4 a6 a8 a10 7 -6.8948 -2.146397E-04 -8.412506E-06 4.822056E-07 -2.538298E-09 8 0.0827 5.045574E-04 -1.271486E-05 6.223030E-07 -1.254742E-08 11 -1.5164 2.704484E-03 -7.171441E-04 6.289515E-04 -3.726218E-04 12 8.2872 3.994132E-03 -3.400475E-04 3.944555E-05 -3.903591E-05 15 8.8206 -3.435467E-03 -5.732754E-04 7.568240E-05 -2.718095E-05 16 0.0508 -3.224558E-03 -2.063146E-04 1.336924E-05 7.076333E-06 19 -0.0003 -4.046673E-03 1.203531E-03 -5.354413E-05 -8.399497E-06 20 3.1551 -6.526234E-03 9.985812E-04 -6.920478E-05 2.121299E-06 21 -1.0491 -2.416804E-04 -1.660149E-04 1.305389E-05 -6.613111E-07 22 -16.0244 5.223425E-03 -6.765157E-04 4.337212E-05 -1.812052E-06 Surface number a12 a14 a16 a18 a20 7 -7.085029E-10 4.855063E-11 -1.319226E-12 0.000000E+00 0.000000E+00 8 -4.167445E-10 3.987169E-11 -1.018010E-12 0.000000E+00 0.000000E+00 11 1.351657E-04 -3.112449E-05 4.392356E-06 -3.477237E-07 1.184528E-08 12 1.709966E-05 -4.402407E-06 6.450106E-07 -5.057379E-08 1.649219E-09 15 6.977788E-06 -1.271752E-06 1.480443E-07 -1.027577E-08 3.563771E-10 16 -2.430677E-06 3.809931E-07 -3.358463E-08 1.605139E-09 -3.227007E-11 19 2.021414E-06 -2.054082E-07 1.166278E-08 -3.590969E-10 4.708066E-12 20 1.488595E-07 -2.137726E-08 1.105458E-09 -2.819284E-11 2.966446E-13 21 2.368161E-08 -5.629128E-10 8.310670E-12 -6.881180E-14 2.433893E-16 22 5.193062E-08 -9.988270E-10 1.222288E-11 -8.572370E-14 2.617965E-16

[0074] Table 2 shows a set of design values of the aspherical coefficients of the lenses in the wide-angle fixed-focus lens in the first embodiment. The specific numerical values can be adjusted according to product requirements, which is not a limitation to the embodiments of the present invention. The wide-angle fixed-focus lens shown in Table 2 can be Figure 1 as shown in. The meaning of the surface number column in Table 2 is consistent with that of the surface number in Table 1. "E" in each embodiment of the present invention represents the exponent with base 10.

[0075] Optionally, the surface of the aspherical lens satisfies the formula:

[0076]

[0077] Among them, z is the axial sagittal height in the Z direction of the aspheric surface; r is the height of the aspheric surface; c is the curvature of the fitted spherical surface, numerically the reciprocal of the radius of curvature; k is the fitted conic coefficient; a4 to a 20 are the coefficients of the 4th, 6th, 8th, 10th, 12th, 14th, 16th, 18th, and 20th orders of the aspheric polynomial.

[0078] Exemplarily, in the first embodiment, the maximum diameter that the image plane size can reach is 16.2 mm, the field of view angle is 165.4°, F is 5.00, and the f-number (i.e., F / #) is 2.80. The TTL is 32.280 mm, and the applicable wavelength band includes 436 nm to 870 nm.

[0079] Exemplarily, in the first embodiment, L1R1 / L1R2 = 6.590, F1 / F = -1.408, F5 / F = 2.453, ΦL1 / TTL = 0.045, (ΦL1 × TTL) / IH = 0.003, L1R1 / ΦL1 = 23.742, BFL / TTL = 0.059, F / TTL = 0.155, F10 / F = 1.911, F9 / F = -2.286, F10 / F9 = -0.836.

[0080] Figure 2 This is the field curvature diagram of the wide-angle fixed-focus lens provided in the first embodiment of the present invention. Refer to Figure 2 , the horizontal coordinate represents the magnitude of the field curvature, with the unit of mm; the vertical coordinate represents the normalized image height, without a unit; where T represents the meridian and S represents the sagittal. It can be Figure 2 seen that the field curvature of the wide-angle fixed-focus lens provided in this embodiment is effectively controlled, that is, when imaging, the difference in image quality between the center and the periphery is small.

[0081] Figure 3 This is the distortion diagram of the wide-angle fixed-focus lens provided in the first embodiment of the present invention. Refer to Figure 3 , the horizontal coordinate represents the magnitude of the distortion, with the unit of %; the vertical coordinate represents the normalized image height, without a unit.

[0082] Figures 4 - 9 This is the fan diagram of the wide-angle fixed-focus lens provided in the first embodiment of the present invention. Refer to Figures 4 - 9 , the fan diagram is one of the most commonly used evaluation methods in modern optical design. The abscissa is the beam aperture, and the ordinate is the lateral aberration. The most ideal curve is a straight line that coincides with the abscissa, indicating that all rays converge at the same point on the image plane. The corresponding interval on the ordinate of the curve is the maximum dispersion range of the beam on the ideal image plane. The fan diagram can not only reflect the monochromatic aberration of different wavelengths but also represent the magnitude of the lateral chromatic aberration. It can be Figures 4 - 9It can be seen that the wide-angle fixed-focus lens is well approximated to the abscissa at each wavelength in each field of view, indicating that the vertical aberration of each wavelength of the system is well corrected. At the same time, there is no obvious dispersion among the wavelengths, indicating that the chromatic aberration of the wide-angle fixed-focus lens is also well corrected, thus ensuring that the wide-angle fixed-focus lens can meet the high-resolution imaging requirements.

[0083] Figure 10 This is the vertical chromatic aberration diagram of the wide-angle fixed-focus lens provided in the first embodiment of the present invention. Refer to Figure 10 , the vertical direction represents the normalization of the field of view, and 0 represents on the optical axis; the main wavelength is 546 nm, and the horizontal direction represents the offset relative to the main wavelength, with the unit of micrometer (um). From Figure 10 it can be seen that the vertical chromatic aberrations of different wavelengths are all controlled within a good range, indicating that the vertical chromatic aberration of the wide-angle fixed-focus lens is well controlled and can meet the requirements of wide-spectrum applications.

[0084] Figure 11 This is the axial aberration diagram of the wide-angle fixed-focus lens provided in the first embodiment of the present invention. Refer to Figure 11 , the vertical direction represents the normalization of the aperture, 0 represents on the optical axis, and the vertex in the vertical direction represents the maximum pupil radius; the main wavelength is 546 nm, and the horizontal direction represents the offset relative to the main wavelength, with the unit of millimeter (mm). From Figure 11 it can be seen that the axial aberrations of different wavelengths with a normalized aperture of 0 to 1.0 are all controlled within a reasonable range, indicating that the vertical chromatic aberration of the wide-angle fixed-focus lens is well controlled.

[0085] Embodiment 2

[0086] Similarities with the above embodiments will not be elaborated here.

[0087] Table 3 shows a set of design values of the wide-angle fixed-focus lens in Embodiment 2

[0088] Surface number Surface type Radius of curvature Thickness Refractive index Abbe number 1 Standard surface 35.2641 1.1596 1.87 39.74 2 Standard surface 5.3559 1.8999 3 Standard surface 12.5350 0.6093 1.74 77.11 4 Aspherical surface 7.2901 2.8748 5 Aspherical surface -6.7805 0.9360 1.81 31.43 6 Standard surface -13.9309 0.0581 7 Aspherical surface 15.6919 2.8714 1.85 41.13 8 Aspherical surface -8.4320 1.7549 9 Standard surface INF 1.5999 10 STO INF 0.0609 11 Aspherical surface 14.4813 1.6616 1.50 85.55 12 Aspherical surface -10.2620 0.1394 13 Standard surface -215.3604 1.6604 1.50 72.71 14 Standard surface -5.7299 0.0761 15 Aspherical surface -14.3737 0.8655 1.69 30.86 16 Aspherical surface 5.2894 0.8555 17 Standard surface 13.0496 2.9029 1.49 77.79 18 Standard surface -8.1962 0.4740 19 Aspherical surface -4.5745 0.6369 1.69 37.66 20 Aspherical surface -12.0294 3.6401 21 Aspherical surface 7.8747 3.4090 1.58 75.55 22 Aspherical surface -25.1586 0.6168 23 Standard surface INF 0.7500 1.52 64.17 24 Standard surface INF 0.7778 25 IMX INF -

[0089] Table 3 shows a set of design values of the wide-angle fixed-focus lens in Embodiment 2, and the specific numerical values can be adjusted according to product requirements, which is not a limitation to the embodiments of the present invention. The wide-angle fixed-focus lens shown in Table 3 can be as Figure 12 shown in.

[0090] Table 4 shows a set of design values of the aspheric coefficients of the lenses in the wide-angle fixed-focus lens in Embodiment 2

[0091] Surface number K a4 a6 a8 a10 7 -6.7077 -2.163006E-04 -8.339328E-06 4.725313E-07 -2.929993E-09 8 0.0832 5.041704E-04 -1.293302E-05 6.255390E-07 -1.244923E-08 11 -1.1601 2.721663E-03 -7.106030E-04 6.301740E-04 -3.724503E-04 12 8.3136 3.968997E-03 -3.372762E-04 4.116508E-05 -3.860944E-05 15 9.0451 -3.485622E-03 -5.764125E-04 7.612945E-05 -2.713049E-05 16 0.0489 -3.223790E-03 -2.079361E-04 1.330341E-05 7.081761E-06 19 -0.0010 -4.078152E-03 1.205940E-03 -5.345454E-05 -8.397090E-06 20 3.1428 -6.476052E-03 9.976275E-04 -6.923327E-05 2.121106E-06 21 -1.2481 -3.126272E-04 -1.644567E-04 1.305733E-05 -6.614045E-07 22 -42.8409 5.280790E-03 -6.811655E-04 4.336167E-05 -1.811851E-06 Surface number a12 a14 a16 a18 a20 7 -7.129542E-10 5.085645E-11 -1.090182E-12 0.000000E+00 0.000000E+00 8 -3.987954E-10 4.126447E-11 -8.925126E-13 0.000000E+00 0.000000E+00 11 1.351980E-04 -3.111890E-05 4.393640E-06 -3.476380E-07 1.178009E-08 12 1.715588E-05 -4.399857E-06 6.440035E-07 -5.076588E-08 1.676487E-09 15 6.976423E-06 -1.272908E-06 1.478075E-07 -1.027793E-08 3.649147E-10 16 -2.429318E-06 3.810974E-07 -3.358367E-08 1.604872E-09 -3.194005E-11 19 2.021475E-06 -2.054018E-07 1.166337E-08 -3.590649E-10 4.708922E-12 20 1.488781E-07 -2.137652E-08 1.105479E-09 -2.819028E-11 2.969386E-13 21 2.368041E-08 -5.629144E-10 8.311054E-12 -6.879708E-14 2.438018E-16 22 5.193413E-08 -9.987898E-10 1.222319E-11 -8.572385E-14 2.617128E-16

[0092] Table 4 shows a set of design values for the aspheric coefficients of the lenses in the wide-angle fixed-focus lens of Embodiment 2. The specific numerical values can be adjusted according to product requirements and do not limit the embodiments of the present invention. The fixed-focus lens shown in Table 4 can be Figure 12 as shown in

[0093] Exemplarily, in Embodiment 2, the maximum diameter that the image plane size can reach is 16.8 mm, the field of view angle is 153.9°, F is 5.98, the aperture number (i.e., F / #) is 2.80. The TTL is 32.291 mm, and the applicable wavelength band includes 436 nm to 870 nm.

[0094] Exemplarily, in Embodiment 2, L1R1 / L1R2 = 6.584, F1 / F = -1.226, F5 / F = 2.061, ΦL1 / TTL = 0.036, (ΦL1 × TTL) / IH = 0.002, L1R1 / ΦL1 = 30.411, BFL / TTL = 0.066, F / TTL = 0.185, F10 / F = 1.776, F9 / F = -1.839, F10 / F9 = -0.966.

[0095] Embodiment 3

[0096] Similarities with the above embodiments will not be elaborated here.

[0097] Table 5 shows a set of design values for the wide-angle fixed-focus lens in Embodiment 3

[0098] Surface number Surface type Radius of curvature Thickness Refractive index Abbe number 1 Standard surface 38.0985 0.5228 1.88 67.21 2 Standard surface 5.3975 1.9174 3 Standard surface 12.5944 0.5534 1.74 75.66 4 Aspherical surface 7.2321 2.8862 5 Aspherical surface -6.8247 0.9372 1.80 38.55 6 Standard surface -14.0539 0.0536 7 Aspherical surface 15.6958 2.8169 1.85 49.30 8 Aspherical surface -8.4294 1.6978 9 Standard surface INF 1.5428 10 STO INF 0.0695 11 Aspherical surface 14.4457 1.5988 1.50 89.44 12 Aspherical surface -10.2604 0.1414 13 Standard surface -237.4167 1.6450 1.50 73.24 14 Standard surface -5.7401 0.0744 15 Aspherical surface -14.4684 0.8672 1.69 28.95 16 Aspherical surface 5.2823 0.8510 17 Standard surface 13.0065 2.8068 1.50 40.96 18 Standard surface -8.2090 0.4810 19 Aspherical surface -4.5692 0.6221 1.67 45.92 20 Aspherical surface -11.9468 3.6103 21 Aspherical surface 8.0810 3.4161 1.60 75.66 22 Aspherical surface -22.5737 0.6056 23 Standard surface INF 0.7000 1.52 64.17 24 Standard surface INF 0.7888 25 IMX INF -

[0099] Table 5 shows a set of design values for the wide-angle fixed-focus lens in Embodiment 3. The specific numerical values can be adjusted according to product requirements and do not limit the embodiments of the present invention. The wide-angle fixed-focus lens shown in Table 5 can be Figure 23 as shown in

[0100] Table 6 shows a set of design values for the aspheric coefficients of the lenses in the wide-angle fixed-focus lens of Embodiment 3

[0101] Surface number K a4 a6 a8 a10 7 -6.9612 -2.237310E-04 -8.236342E-06 4.841855E-07 -2.677511E-09 8 0.0694 5.078711E-04 -1.281532E-05 6.293274E-07 -1.271191E-08 11 -0.8163 2.738922E-03 -7.130851E-04 6.299549E-04 -3.724663E-04 12 8.3604 3.951021E-03 -3.365884E-04 4.073789E-05 -3.876954E-05 15 9.1391 -3.478720E-03 -5.787139E-04 7.624173E-05 -2.714558E-05 16 0.0535 -3.219606E-03 -2.063049E-04 1.345414E-05 7.091544E-06 19 0.0003 -4.063379E-03 1.205611E-03 -5.345839E-05 -8.397590E-06 20 3.1500 -6.479813E-03 9.980006E-04 -6.923082E-05 2.121117E-06 21 -1.5281 -3.212612E-04 -1.641526E-04 1.306437E-05 -6.613370E-07 22 -1.4622 5.460094E-03 -6.800418E-04 4.335725E-05 -1.811909E-06 Surface number a12 a14 a16 a18 a20 7 -7.258604E-10 4.938004E-11 -1.148241E-12 0.000000E+00 0.000000E+00 8 -3.966372E-10 4.115760E-11 -9.671164E-13 0.000000E+00 0.000000E+00 11 1.351929E-04 -3.112041E-05 4.393273E-06 -3.476849E-07 1.178723E-08 12 1.713124E-05 -4.401638E-06 6.444141E-07 -5.070295E-08 1.668587E-09 15 6.968314E-06 -1.274432E-06 1.476219E-07 -1.026612E-08 3.765472E-10 16 -2.429973E-06 3.808892E-07 -3.361163E-08 1.604267E-09 -3.149490E-11 19 2.021421E-06 -2.054050E-07 1.166328E-08 -3.590642E-10 4.709364E-12 20 1.488721E-07 -2.137614E-08 1.105455E-09 -2.819158E-11 2.967478E-13 21 2.368060E-08 -5.629225E-10 8.310858E-12 -6.880009E-14 2.437609E-16 22 5.193369E-08 -9.987862E-10 1.222326E-11 -8.572257E-14 2.617185E-16

[0102] Table 6 shows a set of design values for the aspheric coefficients of the lenses in the wide-angle fixed-focus lens of Embodiment 3. The specific numerical values can be adjusted according to product requirements and do not limit the embodiments of the present invention. The fixed-focus lens shown in Table 6 can be Figure 23 as shown in

[0103] Exemplarily, in the third embodiment, the maximum diameter that the image plane size can reach is 16.6 mm, the field of view angle is 154.9°, F is 5.70, the aperture number (i.e., F / #) is 2.80. The TTL is 31.206 mm, and the applicable wavelength band includes 436 nm to 870 nm.

[0104] Exemplarily, in the third embodiment, L1R1 / L1R2 = 7.059, F1 / F = -1.264, F5 / F = 2.157, ΦL1 / TTL = 0.017, (ΦL1 × TTL) / IH = 0.001, L1R1 / ΦL1 = 72.874, BFL / TTL = 0.067, F / TTL = 0.067, F10 / F = 1.813, F9 / F = -1.981, F10 / F9 = -0.915.

[0105] Note that the above is only the preferred embodiment of the present invention and the technical principles applied. Those skilled in the art will understand that the present invention is not limited to the specific embodiments described herein, and various obvious changes, re-adjustments, combinations with each other, and substitutions can be made by those skilled in the art without departing from the protection scope of the present invention. Therefore, although the present invention has been described in more detail through the above embodiments, the present invention is not limited to the above embodiments. Without departing from the concept of the present invention, more other equivalent embodiments can be included, and the scope of the present invention is determined by the scope of the appended claims.

Claims

1. A wide-angle fixed-focus lens, characterized in that, It includes a first lens, a second lens, a third lens, a fourth lens, a fifth lens, a sixth lens, a seventh lens, an eighth lens, a ninth lens, and a tenth lens arranged in sequence from the object side to the image side along the optical axis; The fourth lens, the fifth lens, and the eighth lens have positive optical powers, and the seventh lens has a negative optical power; The wide-angle fixed-focus lens further includes a diaphragm, and the diaphragm is located between the fourth lens and the fifth lens.

2. The wide-angle fixed-focus lens according to claim 1, wherein, The sixth lens and the tenth lens have positive optical powers; The first lens, the second lens, the third lens, and the ninth lens have negative optical powers.

3. The wide-angle fixed-focus lens according to claim 1, wherein, The fourth lens, the fifth lens, the seventh lens, the ninth lens, and the tenth lens are glass aspherical lenses.

4. The wide-angle fixed-focus lens according to claim 3, wherein The fourth lens is a biconvex lens, the fifth lens is a biconvex lens, and the seventh lens is a biconcave lens; The object side surface of the ninth lens is recessed toward the object side, and the image side surface of the ninth lens is convex toward the image side; the tenth lens is a biconvex lens.

5. The wide-angle fixed-focus lens according to claim 1, wherein The radius of curvature of the object side surface of the first lens is L1R1, the radius of curvature of the image side surface of the first lens is L1R2, the focal length of the first lens is F1, the effective focal length of the wide-angle fixed-focus lens is F, and the refractive index of the first lens is Nd1, satisfying: 6.110 ≤ L1R1 / L1R2 ≤ 7.533; -1.590 ≤ F1 / F ≤ -1.044; 1.80 ≤ Nd1 ≤ 1.

93.

6. The wide-angle fixed-focus lens according to claim 1, wherein The focal length of the fifth lens is F5, the Abbe number of the fifth lens is Vd5, and the effective focal length of the wide-angle fixed-focus lens is F, satisfying: 1.669 ≤ F5 / F ≤ 2.884; 75.00 ≤ Vd5 ≤ 96.

00.

7. The wide-angle fixed-focus lens according to claim 1, wherein, The maximum lens diameter of the first lens is ΦL1, the overall optical length of the wide-angle fixed-focus lens is TTL, the maximum imaging image height of the wide-angle fixed-focus lens is IH, and the radius of curvature of the object side surface of the first lens is L1R1, satisfying: 0.000 ≤ ΦL1 / TTL ≤ 0.074; 0.000 ≤ (ΦL1 × TTL) / IH ≤ 0.010; 15.232 ≤ L1R1 / ΦL1 ≤ 90.

006.

8. The wide-angle fixed-focus lens according to claim 1, wherein, The overall optical length of the wide-angle fixed-focus lens is TTL, the effective focal length of the wide-angle fixed-focus lens is F, and the back focal length of the wide-angle fixed-focus lens is BFL, satisfying: 0.051 ≤ BFL / TTL ≤ 0.075; 0.125 ≤ F / TTL ≤ 0.

216.

9. The wide-angle fixed-focus lens according to claim 1, characterized in that, The focal length of the ninth lens is F9, the focal length of the tenth lens is F10, and the effective focal length of the wide-angle fixed-focus lens is F, satisfying: 1.642 ≤ F10 / F ≤ 2.045; -2.733 ≤ F9 / F ≤ -1.391; -1.096 ≤ F10 / F9 ≤ -0.

705.

10. The wide-angle fixed-focus lens according to claim 1, wherein, The aperture of the wide-angle fixed-focus lens is FNO, and the field of view of the wide-angle fixed-focus lens is FOV, satisfying: FNO ≥ 2.85 and / or FOV ≤ 170°.

Images