Ultra-wide-angle fixed focal length lens

Abstract

The application provides a kind of super wide angle fixed focus lens, relating to optical lens technical field.Super wide angle fixed focus lens includes negative power first lens, negative power second lens, positive power third lens, positive power fourth lens, negative power fifth lens, positive power sixth lens and positive power seventh lens arranged in order along optical axis from object side to image side;It also includes diaphragm, and the diaphragm is located between the third lens and the fourth lens.The embodiment of the application provides a kind of super wide angle fixed focus lens, in the case of having large field angle, miniaturization is still adapted to large target chip, more chip types can be compatible, and day and night can be focused, can meet the use demand in more situations.

Description

Technical Field

[0001] This invention relates to the field of optical lens technology, and more particularly to ultra-wide-angle fixed-focus lenses. Background Technology

[0002] With the development of various smart devices, there are more and more scenarios that require a wider field of view. Most lenses on the market that meet this application scenario have a large first lens diameter, resulting in a large size. However, the resulting requirements for precision leave little space for lens assembly. This invention achieves miniaturization while having the advantage of a larger target surface, which can be applied to more usage scenarios and has a broad market prospect. Summary of the Invention

[0003] This invention provides an ultra-wide-angle fixed-focus lens that, while possessing a large field of view, achieves miniaturization and can still adapt to large-area chips, is compatible with more chip types, and can achieve day and night co-focus, thus meeting the usage needs in more situations.

[0004] This invention provides an ultra-wide-angle fixed-focus lens, comprising a first lens with negative optical power, a second lens with negative optical power, a third lens with positive optical power, a fourth lens with positive optical power, a fifth lens with negative optical power, a sixth lens with positive optical power, and a seventh lens with positive optical power arranged sequentially from the object side to the image side along the optical axis.

[0005] It also includes an aperture stop, which is located between the third lens and the fourth lens.

[0006] Optionally, the first lens and the third lens are glass spherical lenses, and the second lens, the fourth lens, the fifth lens, the sixth lens and the seventh lens are plastic aspherical lenses.

[0007] Optionally, the object-side surface of the first lens protrudes towards the object side, and the image-side surface of the first lens is recessed towards the image side;

[0008] The second lens and the fifth lens are biconcave lenses;

[0009] The fourth lens is a biconvex lens;

[0010] The object-side surface of the sixth lens is concave towards the object side, and the image-side surface of the sixth lens is convex towards the image side.

[0011] Optionally, the maximum field of view of the ultra-wide-angle fixed-focus lens is DFOV, the image height corresponding to the maximum field of view of the ultra-wide-angle fixed-focus lens is H, and the total focal length of the ultra-wide-angle fixed-focus lens is f, satisfying:

[0012]

[0013] Alternatively, 0.273 ≤ f / H ≤ 0.34.

[0014] Optionally, the optical power of the first lens is The optical power of the second lens is The optical power of the fourth lens is: The optical power of the fifth lens is The optical power of the seventh lens is The optical power of the ultra-wide-angle fixed-focus lens is: At least one of the following conditions must be met:

[0015]

[0016] Optionally, the refractive index of the first lens is Nd1, the Abbe number of the first lens is Vd1, and the refractive index of the third lens is Nd3, the Abbe number of the third lens is Vd3, satisfying:

[0017] 1.7≤Nd1≤1.8, 56.7≤Vd1≤60.2;

[0018] And / or, 1.81≤Nd3≤2.02, 17≤Vd3≤19.1.

[0019] Optionally, the back focal length of the ultra-wide-angle fixed-focus lens is BFL, and the total lens length of the ultra-wide-angle fixed-focus lens is TTL, satisfying:

[0020] 0.195≤BFL / TTL≤0.224.

[0021] Optionally, the effective optical aperture of the seventh lens is D7, the image height corresponding to the maximum field of view of the ultra-wide-angle fixed-focus lens is H, and the total focal length of the ultra-wide-angle fixed-focus lens is f, satisfying:

[0022]

[0023] Optionally, the total length of the ultra-wide-angle fixed-focus lens is TTL, and the total focal length of the ultra-wide-angle fixed-focus lens is f, satisfying:

[0024] 0.118≤f / TTL≤0.147.

[0025] This invention provides an ultra-wide-angle fixed-focus lens, comprising seven lenses, designated as the first to the seventh lens. The first and second lenses have negative optical power, introducing a wider field of view while smoothing out excessive light refraction, thus preventing the introduction of greater aberrations. The third lens, with positive optical power, converges the passing light, ensuring that light can pass through a sufficiently large aperture. The fourth and fifth lenses, with their combined positive and negative optical power, compensate for aberrations such as chromatic aberration and field curvature generated at the front end, reducing the burden on the rear lenses to correct aberrations. The fifth lens, with its negative optical power, increases the imaging area of ​​the ultra-wide-angle fixed-focus lens, allowing for a greater imaging height. The seventh lens, with its positive optical power, helps limit the size of the principal ray angle to match the chip's CRA curve requirements. Attached Figure Description

[0026] Figure 1 This is a schematic diagram of the structure of an ultra-wide-angle fixed-focus lens provided in Embodiment 1 of the present invention;

[0027] Figure 2 This is a schematic diagram of a ray fan pattern provided in Embodiment 1 of the present invention;

[0028] Figure 3 This is a schematic diagram of a vertical color difference provided in Embodiment 1 of the present invention;

[0029] Figure 4 This is a schematic diagram of the structure of an ultra-wide-angle fixed-focus lens provided in Embodiment 2 of the present invention;

[0030] Figure 5 This is a schematic diagram of a ray fan pattern provided in Embodiment 2 of the present invention;

[0031] Figure 6 This is a schematic diagram of a vertical color difference provided in Embodiment 2 of the present invention;

[0032] Figure 7 This is a schematic diagram of the structure of an ultra-wide-angle fixed-focus lens provided in Embodiment 3 of the present invention;

[0033] Figure 8 This is a schematic diagram of a ray fan pattern provided in Embodiment 3 of the present invention;

[0034] Figure 9 This is a schematic diagram of a vertical color difference provided in Embodiment 3 of the present invention. Detailed Implementation

[0035] The present invention will now be described in further detail with reference to the accompanying drawings and embodiments. It should be understood that the specific embodiments described herein are merely illustrative of the invention and not intended to limit it. Furthermore, it should be noted that, for ease of description, the accompanying drawings show only the parts relevant to the present invention, and not all of the structures.

[0036] Example 1

[0037] Figure 1 This is a schematic diagram of the structure of an ultra-wide-angle fixed-focus lens provided in Embodiment 1 of the present invention, with reference to... Figure 1 The ultra-wide-angle fixed-focus lens includes, along the optical axis from object side to image side, a first lens L1 with negative optical power, a second lens L2 with negative optical power, a third lens L3 with positive optical power, a fourth lens L4 with positive optical power, a fifth lens L5 with negative optical power, a sixth lens L6 with positive optical power, and a seventh lens L7 with positive optical power. The ultra-wide-angle fixed-focus lens also includes an aperture stop STO, located between the third lens L3 and the fourth lens L4.

[0038] Optical power is equal to the difference between the convergence of the image-side beam and the convergence of the object-side beam; it characterizes the ability of an optical system to deflect light. The larger the absolute value of the optical power, the stronger its ability to bend light; the smaller the absolute value, the weaker its ability to bend light. When the optical power is positive, the refraction of light is converging; when the optical power is negative, the refraction of light is diverging.

[0039] This invention provides an ultra-wide-angle fixed-focus lens, comprising seven lenses, namely, a first lens L1 to a seventh lens L7. The first lens L1 and the second lens L2 have negative optical power, introducing a wider field of view while making the refraction of light more gradual, avoiding the introduction of greater aberrations. The third lens L3, with positive optical power, converges the passing light, ensuring that light can pass through a sufficiently large aperture (STO). The fourth lens L4 and the fifth lens L5, with their combined positive and negative optical power, compensate for aberrations such as chromatic aberration and field curvature generated at the front end, reducing the pressure on the rear lenses to correct aberrations. The negative optical power of the fifth lens L5 can increase the imaging area of ​​the ultra-wide-angle fixed-focus lens, allowing the final image to achieve a greater imaging height. The positive optical power of the seventh lens L7 helps to limit the size of the principal ray angle to match the chip's CRA curve requirements.

[0040] Optionally, the first lens L1 and the third lens L3 are glass spherical lenses, and the second lens L2, the fourth lens L4, the fifth lens L5, the sixth lens L6, and the seventh lens L7 are plastic aspherical lenses. The ultra-wide-angle fixed-focus lens provided in this embodiment of the invention is a glass-plastic hybrid lens, employing two glass spherical lenses and five plastic aspherical lenses.

[0041] Optionally, the object-side surface of the first lens L1 is convex towards the object side, and the image-side surface of the first lens L1 is concave towards the image side. The first lens L1 is a convex-concave lens. The second lens L2 and the fifth lens L5 are biconcave lenses. The fourth lens L4 is a biconvex lens. The object-side surface of the sixth lens L6 is concave towards the object side, and the image-side surface of the sixth lens L6 is convex towards the image side. The sixth lens L6 is a concave-convex lens. The concavity / convexity of the third lens L3 and the seventh lens L7 can be set according to requirements.

[0042] Optionally, the maximum field of view of the ultra-wide-angle fixed-focus lens is DFOV, the image height corresponding to the maximum field of view of the ultra-wide-angle fixed-focus lens is H, and the total focal length of the ultra-wide-angle fixed-focus lens is f, satisfying: When this relationship is satisfied, the needs for wide-range detection and high-quality imaging can be balanced, and the requirements for a large target surface can still be met under the condition of ultra-wide-angle, adapting to more types of chips on the market.

[0043] Optionally, 0.273≤f / H≤0.34. When the total focal length of the ultra-wide-angle fixed-focus lens and the image height corresponding to the maximum field of view of the ultra-wide-angle fixed-focus lens satisfy 0.273≤f / H≤0.34, the condition for the ultra-wide-angle fixed-focus lens to form a large target surface can be achieved.

[0044] Optionally, the optical power of the first lens L1 is The optical power of the second lens L2 is: The optical power of the fourth lens L4 is The optical power of the fifth lens L5 is The optical power of the seventh lens L7 is The optical power of the ultra-wide-angle prime lens is At least one of the following conditions must be met:

[0045] Among them, the seventh lens L7 has a positive optical power, which satisfies When the range is within the range, it is beneficial to suppress the angle of the edge field of view incident on the imaging surface, and to effectively transmit more light beams to the imaging surface in order to match the chip CRA curve requirements.

[0046] Among them, the first lens L1 and the second lens L2 have negative optical power. When the range is wide, it is beneficial to converge light rays at a larger angle, thus satisfying a larger detection range.

[0047] Among them, the fourth lens L4 and the fifth lens L5 satisfy When the lens is within the range, the fourth lens L4 has positive optical power and the fifth lens L5 has negative optical power. The combination of positive and negative lenses compensates for the chromatic aberration introduced at the front end, providing a basis for day and night confocal focusing of the ultra-wide-angle fixed-focus lens.

[0048] Optionally, the refractive index of the first lens L1 is Nd1, the Abbe number of the first lens L1 is Vd1, the refractive index of the third lens L3 is Nd3, and the Abbe number of the third lens L3 is Vd3, satisfying: 1.7≤Nd1≤1.8, 56.7≤Vd1≤60.2; and / or, 1.81≤Nd3≤2.02, 17≤Vd3≤19.1.

[0049] The first lens L1 is a convex-concave negative lens and is the first lens of the ultra-wide-angle fixed-focus lens. When the first lens L1 satisfies the range of 1.7≤Nd1≤1.8, it can reduce the angle of light, share the aberration pressure of the large field of view, and at the same time effectively compress the lens aperture, realizing the miniaturization of the ultra-wide-angle fixed-focus lens.

[0050] Among them, the third lens L3 has a positive optical power. When the third lens L3, as a positive lens, satisfies 1.81≤Nd3≤2.02 and 17≤Vd3≤19.1, it can effectively converge the light from the front, allowing the light to pass smoothly through the aperture stop STO (i.e., the aperture), ensuring that the lens has a large ultra-wide-angle fixed focal length and sufficient light intake.

[0051] Optionally, the back focal length of the ultra-wide-angle fixed-focus lens is BFL, and the total lens length is TTL, satisfying: 0.195≤BFL / TTL≤0.224. The reasonable selection of the back focal length and total lens length of the ultra-wide-angle fixed-focus lens ensures sufficient mounting space for the image sensor and flat panel filter, prevents interference with the base and housing during installation, and maintains a simple manufacturing process.

[0052] Optionally, the effective optical aperture of the seventh lens L7 is D7, the image height corresponding to the maximum field of view of the ultra-wide-angle fixed-focus lens is H, and the total focal length of the ultra-wide-angle fixed-focus lens is f, satisfying: By designing the above parameters of the seventh lens L7, the following conditions are met. When the light is applied, it allows the overall light to transition relatively smoothly to the image plane, effectively limiting the CRA (Critical Aspect Ratio). Ultra-wide-angle prime lenses have strong tolerance and manufacturability.

[0053] Optionally, the total length of the ultra-wide-angle fixed-focus lens is TTL, and the total focal length of the ultra-wide-angle fixed-focus lens is f, satisfying: 0.118≤f / TTL≤0.147. This allows for further effective reduction of the size of the ultra-wide-angle fixed-focus lens, achieving miniaturization.

[0054] For example, the ultra-wide-angle fixed-focus lens also includes a flat glass CG. The flat glass CG is located between the seventh lens L7 and the image plane IMA. The flat glass CG can protect the photosensitive chip in the imaging sensor, which is used to convert the light signals collected by the ultra-wide-angle fixed-focus lens into electrical signals, thereby ensuring the imaging effect of the ultra-wide-angle fixed-focus lens.

[0055] For example, in implementation one, f / H = 0.317. Nd1=1.7. Vd1=58.1. Nd3=1.81. Vd3=19.1.

[0056] BFL / TTL = 0.224. f / TTL = 0.147. f = 2.16mm. Aperture: f / 2.07. Field of view: 180°. TTL = 14.7mm. Image size: φ6.8mm.

[0057] Table 1. Design values ​​for an ultra-wide-angle fixed-focus lens in Example 1.

[0058] Face number face shape radius of curvature thickness Refractive index Abbe number OBJ Standard surface unlimited unlimited S1 Standard surface 8.025 1.368 1.70 58.1 S2 Standard surface 2.419 2.461 S3 Extended odd-order aspherical surfaces -3.572 1.178 1.54 55.7 S4 Extended odd-order aspherical surfaces 6.694 0.081 S5 Standard surface 3.119 1.284 1.81 19.1 S6 Standard surface 5.766 0.130 STO Standard surface unlimited 0.034 S7 Extended odd-order aspherical surfaces 3.104 1.437 1.54 55.7 S8 Extended odd-order aspherical surfaces -2.083 0.036 S9 Extended odd-order aspherical surfaces -3.963 0.601 1.64 55.7 S10 Extended odd-order aspherical surfaces 4.161 0.194 S11 Extended odd-order aspherical surfaces -8.965 1.185 1.54 55.7 S12 Extended odd-order aspherical surfaces -2.133 0.048 S13 Extended odd-order aspherical surfaces 3.526 1.372 1.54 55.7 S14 Extended odd-order aspherical surfaces 6.993 0.300 S15 Standard surface unlimited 0.610 1.52 64.2 S16 Standard surface unlimited 2.390 IMA Standard surface unlimited 0.000

[0059] Table 1 shows one design value for the ultra-wide-angle fixed-focus lens in Embodiment 1. The specific values ​​can be adjusted according to product requirements and are not intended to limit the embodiments of the present invention. The ultra-wide-angle fixed-focus lens shown in Table 1 can be... Figure 1 As shown in Table 1, a lens typically consists of two surfaces, each serving as a refractive surface. The surface numbers in Table 1 are assigned based on the surfaces of each lens. Surface number S1 represents the object-side surface of the first lens L1, surface number S2 represents the image-side surface of the first lens L1, and so on; details are omitted here. Note that STO in the surface number column indicates the plane containing the aperture stop. OBJ in the surface number column indicates the object plane. IMA in the surface number column indicates 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 surface closer to the image side, while a negative radius of curvature value indicates that the center of curvature is on the surface farther from the image side. "Infinite" in the radius of curvature column indicates that the surface is planar. The unit of radius of curvature is mm. The value in the thickness column indicates the axial distance from the current surface to the next surface. The unit of thickness is mm. The refractive index column indicates the refractive index of the medium between the current surface and the next surface. A blank space in the refractive index column represents the refractive index of air, which is 1. The Abbe number represents the dispersion characteristics of light by the material between the current surface and the next surface. The space indicates that the current position is air.

[0060] Table 2 shows a design value for the aspheric coefficient of the lens in the ultra-wide-angle fixed-focus lens of Example 1.

[0061] Face number S3 S4 S7 S8 S9 k -1.00265E-02 2.73910E-01 -3.31704E-02 1.77770E-02 -4.80291E-01 <![CDATA[a4]]> 3.11466E-02 2.97606E-02 -2.12305E-02 -3.80028E-01 -5.04303E-01 <![CDATA[a6]]> -6.67527E-03 -1.85237E-02 2.32268E-02 1.04643E+00 1.12333E+00 <![CDATA[a8]]> 1.16257E-03 2.38734E-02 7.91583E-04 -1.45604E+00 -1.82831E+00 <![CDATA[a 10 ]]> -1.02475E-04 -1.90068E-02 -4.45872E-01 5.97096E-01 2.21161E+00 <![CDATA[a 12 ]]> -3.26063E-06 -9.92613E-03 1.71022E+00 1.20807E+00 -2.26892E+00 <![CDATA[a 14 ]]> 1.56325E-06 3.92214E-02 -3.22715E+00 -2.15633E+00 2.06341E+00 <![CDATA[a 16 ]]> -1.07236E-07 -4.46133E-02 3.35765E+00 1.47286E+00 -1.50378E+00 <![CDATA[a 18 ]]> 3.36133E-09 3.09918E-02 -1.84479E+00 -4.11741E-01 7.49552E-01 <![CDATA[a 20 ]]> -3.05344E-10 -1.50318E-02 4.16787E-01 -7.10441E-03 -2.10535E-01 <![CDATA[a 22 ]]> 0.00000E+00 5.20033E-03 0.00000E+00 1.84937E-02 2.06523E-02 <![CDATA[a 24 ]]> 0.00000E+00 -1.23900E-03 0.00000E+00 0.00000E+00 1.69652E-03 <![CDATA[a 26 ]]> 0.00000E+00 1.93332E-04 0.00000E+00 0.00000E+00 0.00000E+00 <![CDATA[a 28 ]]> 0.00000E+00 -1.94523E-05 0.00000E+00 0.00000E+00 0.00000E+00 <![CDATA[a 30 ]]> 0.00000E+00 1.18693E-06 0.00000E+00 0.00000E+00 0.00000E+00 Face number S10 S11 S12 S13 S14 k 1.72141E-01 1.49725E+00 1.36664E-02 -3.39027E-02 -1.26095E-01 <![CDATA[a4]]> -1.47131E-01 5.10812E-02 1.89079E-02 -1.99850E-02 -2.12659E-02 <![CDATA[a6]]> 1.14785E-01 -9.24778E-02 4.51392E-03 3.27003E-03 3.95055E-03 <![CDATA[a8]]> -7.21841E-02 1.12827E-01 -6.35321E-03 -4.10887E-04 -4.25742E-04 <![CDATA[a 10 ]]> 2.64693E-02 -9.55338E-02 6.26396E-03 2.17960E-04 -5.38098E-05 <![CDATA[a 12 ]]> -1.19013E-03 5.72736E-02 -2.66752E-03 -1.21141E-04 4.12110E-05 <![CDATA[a 14 ]]> -2.93804E-03 -2.21106E-02 7.34009E-04 3.80299E-05 -8.71289E-06 <![CDATA[a 16 ]]> 1.29505E-03 5.11809E-03 -1.28877E-04 -7.31861E-06 9.20360E-07 <![CDATA[a 18 ]]> -2.74730E-04 -6.43390E-04 1.30600E-05 8.90107E-07 -4.94448E-08 <![CDATA[a 20 ]]> 2.60104E-05 3.36768E-05 -1.09356E-06 -6.68488E-08 1.02885E-09 <![CDATA[a 22 ]]> 0.00000E+00 0.00000E+00 1.80979E-07 2.83073E-09 3.51405E-12 <![CDATA[a 24 ]]> 0.00000E+00 0.00000E+00 -1.32373E-08 -5.17363E-11 0.00000E+00

[0062] Table 2 shows a design value for the aspherical coefficient of the lens in the ultra-wide-angle fixed-focus lens of Embodiment 1. The specific value can be adjusted according to product requirements and is not intended to limit the embodiments of this invention. The ultra-wide-angle fixed-focus lens shown in Table 2 can be... Figure 1 As shown in the table. The meaning of the "Surface Number" column in Table 2 is consistent with that in Table 1. In the embodiments of the present invention, "E" represents an exponent with a base of 10.

[0063] Optionally, the surface of the aspherical lens satisfies the formula:

[0064] Where Z is the aspherical elevation, c is the fundamental curvature at the vertex, k is the conic section constant, r is the radial coordinate perpendicular to the optical axis, and a i a is the coefficient of the higher-order term. 2i r 2i Let i be a higher-order term of the aspherical surface. i is a positive integer from 2 to 15.

[0065] Figure 2 This is a schematic diagram of a ray fan pattern provided in Embodiment 1 of the present invention, for reference only. Figure 2 In a single sub-image, the horizontal axis represents the normalized beam aperture, and the vertical axis represents the transverse aberration. Ideally, each curve should perfectly coincide with the horizontal axis, at which point all rays in that field of view focus at the same point on the image plane. The vertical axis in a single sub-image can also represent the maximum dispersion range of the beam on the ideal image plane. The fan plot not only reflects monochromatic aberrations of different wavelengths but also the magnitude of transverse chromatic aberration. Figure 2 It can be seen that this optical system closely approximates the horizontal axis at all wavelengths under various fields of view, indicating that the transverse aberrations at each wavelength are well corrected. In addition, the curves of each color do not show significant dispersion, indicating that this optical system also has good correction for chromatic aberration, ensuring the imaging requirement of clear images across the entire wavelength range.

[0066] Figure 3 This is a schematic diagram of a vertical color difference provided in Embodiment 1 of the present invention, with reference to... Figure 3 The figure represents the chromatic aberration of each wavelength relative to the center wavelength (0.55 μm) at different image heights on the imaging plane. The horizontal axis represents the transverse chromatic aberration value of each wavelength relative to the center wavelength (in μm), and the vertical axis represents the normalized field of view. As can be seen from the figure, the transverse chromatic aberration of the longest and shortest wavelengths is controlled within ±5 μm, indicating that this optical lens can excellently correct chromatic aberration at the edges of the field of view and the second-order spectrum of the entire image plane.

[0067] Example 2

[0068] The similarities to Example 1 will not be repeated here.

[0069] For example, in implementation two, f / H = 0.34. Nd1=1.8. Vd1=56.7. Nd3=2.02. Vd3=17.

[0070] BFL / TTL = 0.203. f / TTL = 0.144. f = 2.24mm. Aperture: f / 2.05. Field of view: 179°. TTL = 15.57mm. Image size: φ6.6mm.

[0071] Table 3 shows a design value for an ultra-wide-angle fixed-focus lens in Example 2.

[0072] Face number face shape radius of curvature thickness Refractive index Abbe number OBJ Standard surface unlimited unlimited S1 Standard surface 6.214 1.878 1.80 56.7 S2 Standard surface 2.409 2.384 S3 Extended odd-order aspherical surfaces -5.523 0.550 1.54 55.7 S4 Extended odd-order aspherical surfaces 2.839 0.296 S5 Standard surface 4.976 1.918 2.02 17.0 S6 Standard surface 8.000 0.078 STO Standard surface unlimited 0.020 S7 Extended odd-order aspherical surfaces 2.592 1.493 1.54 55.7 S8 Extended odd-order aspherical surfaces -2.719 0.068 S9 Extended odd-order aspherical surfaces -64.194 0.715 1.64 55.7 S10 Extended odd-order aspherical surfaces 3.967 0.100 S11 Extended odd-order aspherical surfaces -7.763 1.487 1.54 55.7 S12 Extended odd-order aspherical surfaces -2.401 0.020 S13 Extended odd-order aspherical surfaces 3.463 1.401 1.54 55.7 S14 Extended odd-order aspherical surfaces 6.016 0.159 S15 Standard surface unlimited 0.610 1.52 64.2 S16 Standard surface unlimited 2.390 IMA Standard surface unlimited 0.000

[0073] Table 3 shows one design value for the ultra-wide-angle fixed-focus lens in Embodiment 2. The specific values ​​can be adjusted according to product requirements and are not intended to limit the embodiments of the present invention. The ultra-wide-angle fixed-focus lens shown in Table 3 can be... Figure 4 As shown in the image.

[0074] Table 4 shows a design value for the aspheric coefficient of the lens in the ultra-wide-angle fixed-focus lens in Example 2.

[0075] Face number S3 S4 S7 S8 S9 k 3.99063E-03 -1.68877E-04 1.32234E-04 -2.53303E-04 3.68478E+01 <![CDATA[a4]]> 1.67063E-02 1.39966E-02 -1.70996E-02 -4.52957E-01 -5.58105E-01 <![CDATA[a6]]> -4.60218E-03 -1.77847E-02 2.00370E-02 1.09828E+00 1.13631E+00 <![CDATA[a8]]> 9.84446E-04 2.80581E-02 -3.84384E-03 -1.45437E+00 -1.81796E+00 <![CDATA[a 10 ]]> -1.10779E-04 -2.03894E-02 -4.22322E-01 5.86819E-01 2.22194E+00 <![CDATA[a 12 ]]> -9.74360E-07 -1.07630E-02 1.71384E+00 1.19880E+00 -2.28182E+00 <![CDATA[a 14 ]]> 1.91639E-06 3.95998E-02 -3.25626E+00 -2.14751E+00 2.05094E+00 <![CDATA[a 16 ]]> -1.88126E-07 -4.44979E-02 3.34491E+00 1.47498E+00 -1.49558E+00 <![CDATA[a 18 ]]> 3.01422E-09 3.10088E-02 -1.79865E+00 -4.12697E-01 7.53351E-01 <![CDATA[a 20 ]]> 2.14179E-10 -1.50490E-02 3.97363E-01 -9.99258E-03 -2.10342E-01 <![CDATA[a 22 ]]> 0.00000E+00 5.18441E-03 0.00000E+00 1.98214E-02 1.76511E-02 <![CDATA[a 24 ]]> 0.00000E+00 -1.23869E-03 0.00000E+00 0.00000E+00 2.62811E-03 <![CDATA[a 26 ]]> 0.00000E+00 1.95033E-04 0.00000E+00 0.00000E+00 0.00000E+00 <![CDATA[a 28 ]]> 0.00000E+00 -1.84862E-05 0.00000E+00 0.00000E+00 0.00000E+00 <![CDATA[a 30 ]]> 0.00000E+00 8.36460E-07 0.00000E+00 0.00000E+00 0.00000E+00 Face number S10 S11 S12 S13 S14 k 9.29517E-05 -8.51530E-05 -2.83817E-07 2.09149E-05 -3.47330E-03 <![CDATA[a4]]> -1.64344E-01 4.57374E-02 1.73122E-02 -1.94486E-02 -2.28658E-02 <![CDATA[a6]]> 1.16745E-01 -8.30719E-02 6.73048E-03 2.80126E-03 4.05921E-03 <![CDATA[a8]]> -7.11557E-02 1.10608E-01 -6.62999E-03 -3.97705E-04 -4.51288E-04 <![CDATA[a 10 ]]> 2.58169E-02 -9.60504E-02 5.99906E-03 2.17438E-04 -6.03171E-05 <![CDATA[a 12 ]]> -1.20708E-03 5.73758E-02 -2.70948E-03 -1.21214E-04 4.13013E-05 <![CDATA[a 14 ]]> -2.88914E-03 -2.20494E-02 7.36328E-04 3.80478E-05 -8.66038E-06 <![CDATA[a 16 ]]> 1.32536E-03 5.11434E-03 -1.26487E-04 -7.31769E-06 9.22703E-07 <![CDATA[a 18 ]]> -2.74701E-04 -6.48391E-04 1.33283E-05 8.89840E-07 -4.94850E-08 <![CDATA[a 20 ]]> 2.26850E-05 3.42478E-05 -1.09429E-06 -6.68389E-08 1.00581E-09 <![CDATA[a 22 ]]> 0.00000E+00 0.00000E+00 1.59087E-07 2.83216E-09 3.58514E-12 <![CDATA[a 24 ]]> 0.00000E+00 0.00000E+00 -1.54746E-08 -5.18721E-11 0.00000E+00

[0076] Table 4 shows a design value for the aspherical coefficient of the lens in the ultra-wide-angle fixed-focus lens of Example 2. The specific value can be adjusted according to product requirements and is not intended to limit the embodiments of this invention. The ultra-wide-angle fixed-focus lens shown in Table 4 can be... Figure 4 As shown in the image.

[0077] Figure 6 This is a schematic diagram of a vertical color difference provided in Embodiment 2 of the present invention, for reference. Figure 6 The transverse chromatic aberration of the longest and shortest wavelengths is controlled within ±4μm, indicating that the optical lens can effectively correct chromatic aberration at the edge of the field of view and the secondary spectrum of the entire image plane.

[0078] Example 3

[0079] The similarities with Embodiment 1 and Embodiment 2 will not be repeated here.

[0080] For example, in implementation two, f / H = 0.273. Nd1=1.73. Vd1=60.2. Nd3=1.96. Vd3=18.

[0081] BFL / TTL = 0.195. f / TTL = 0.118. f = 1.83mm. Aperture: f / 2.06. Field of view: 179°. TTL = 15.5mm. Image size: φ6.7mm.

[0082] Table 5 shows a design value for an ultra-wide-angle fixed-focus lens in Example 3.

[0083] Face number face shape radius of curvature thickness Refractive index Abbe number OBJ Standard surface unlimited unlimited S1 Standard surface 7.819 1.325 1.73 60.2 S2 Standard surface 2.402 2.166 S3 Extended odd-order aspherical surfaces -10.246 0.559 1.54 55.7 S4 Extended odd-order aspherical surfaces 3.012 0.361 S5 Standard surface 8.233 2.630 1.96 18.0 S6 Standard surface -88.000 0.034 STO Standard surface unlimited 0.095 S7 Extended odd-order aspherical surfaces 3.860 1.409 1.54 55.7 S8 Extended odd-order aspherical surfaces -2.240 0.068 S9 Extended odd-order aspherical surfaces -7.443 0.830 1.64 55.7 S10 Extended odd-order aspherical surfaces 3.557 0.164 S11 Extended odd-order aspherical surfaces -5.011 1.202 1.54 55.7 S12 Extended odd-order aspherical surfaces -2.441 0.029 S13 Extended odd-order aspherical surfaces 3.669 1.598 1.54 55.7 S14 Extended odd-order aspherical surfaces -50.134 0.029 S15 Standard surface unlimited 0.610 1.52 64.2 S16 Standard surface unlimited 2.390 IMA Standard surface unlimited 0.000

[0084] Table 5 shows one design value for the ultra-wide-angle fixed-focus lens in Embodiment 3. The specific values ​​can be adjusted according to product requirements and are not intended to limit the embodiments of the present invention. The ultra-wide-angle fixed-focus lens shown in Table 5 can be... Figure 7 As shown in the image.

[0085] Table 6 shows a design value for the aspheric coefficient of the lens in the ultra-wide-angle fixed-focus lens of Example 3.

[0086] Face number S3 S4 S7 S8 S9 k 2.24008E+00 -2.68557E-01 -1.52490E-02 -1.51910E-01 -2.70662E+01 <![CDATA[a4]]> 1.39669E-02 1.44778E-02 -1.40932E-02 -4.22428E-01 -5.43050E-01 <![CDATA[a6]]> -5.50694E-03 -2.17757E-02 1.84855E-02 1.07562E+00 1.13327E+00 <![CDATA[a8]]> 1.13185E-03 2.89775E-02 1.41540E-02 -1.45260E+00 -1.81027E+00 <![CDATA[a 10 ]]> -1.05280E-04 -2.08552E-02 -4.66821E-01 5.93334E-01 2.20409E+00 <![CDATA[a 12 ]]> -1.37613E-06 -1.08350E-02 1.73368E+00 1.20718E+00 -2.26507E+00 <![CDATA[a 14 ]]> 1.26797E-06 3.95843E-02 -3.23613E+00 -2.15634E+00 2.05547E+00 <![CDATA[a 16 ]]> -1.54660E-07 -4.43929E-02 3.34712E+00 1.47002E+00 -1.50719E+00 <![CDATA[a 18 ]]> 1.85280E-08 3.09953E-02 -1.83484E+00 -4.12186E-01 7.52754E-01 <![CDATA[a 20 ]]> -1.29956E-09 -1.50602E-02 4.15645E-01 -3.51681E-03 -2.07735E-01 <![CDATA[a 22 ]]> 0.00000E+00 5.18328E-03 0.00000E+00 1.70603E-02 1.96251E-02 <![CDATA[a 24 ]]> 0.00000E+00 -1.23834E-03 0.00000E+00 0.00000E+00 1.35653E-03 <![CDATA[a 26 ]]> 0.00000E+00 1.95297E-04 0.00000E+00 0.00000E+00 0.00000E+00 <![CDATA[a 28 ]]> 0.00000E+00 -1.83220E-05 0.00000E+00 0.00000E+00 0.00000E+00 <![CDATA[a 30 ]]> 0.00000E+00 7.77242E-07 0.00000E+00 0.00000E+00 0.00000E+00 Face number S10 S11 S12 S13 S14 k 5.02166E-02 -3.12465E-01 7.47176E-03 1.22310E-03 -1.00000E+02 <![CDATA[a4]]> -1.58108E-01 7.08701E-02 2.57623E-02 -1.59079E-02 -1.25465E-02 <![CDATA[a6]]> 1.17096E-01 -9.21246E-02 5.59676E-03 2.21738E-03 3.52283E-03 <![CDATA[a8]]> -7.17258E-02 1.13952E-01 -6.78146E-03 -2.84511E-04 -4.52812E-04 <![CDATA[a 10 ]]> 2.61866E-02 -9.63013E-02 6.31976E-03 2.13573E-04 -4.88982E-05 <![CDATA[a 12 ]]> -1.34239E-03 5.72295E-02 -2.73447E-03 -1.21438E-04 4.09633E-05 <![CDATA[a 14 ]]> -2.93709E-03 -2.20840E-02 7.25006E-04 3.80536E-05 -8.69612E-06 <![CDATA[a 16 ]]> 1.31776E-03 5.12559E-03 -1.27518E-04 -7.31533E-06 9.23514E-07 <![CDATA[a 18 ]]> -2.66353E-04 -6.43074E-04 1.36349E-05 8.89970E-07 -4.93875E-08 <![CDATA[a 20 ]]> 2.24046E-05 3.31405E-05 -9.88456E-07 -6.68560E-08 1.01841E-09 <![CDATA[a 22 ]]> 0.00000E+00 0.00000E+00 1.70578E-07 2.82953E-09 1.67918E-12 <![CDATA[a 24 ]]> 0.00000E+00 0.00000E+00 -2.14455E-08 -5.16210E-11 0.00000E+00

[0087] Table 6 shows a design value for the aspherical coefficient of the lens in the ultra-wide-angle fixed-focus lens of Example 3. The specific value can be adjusted according to product requirements and is not intended to limit the embodiments of the present invention. The ultra-wide-angle fixed-focus lens shown in Table 6 can be... Figure 7 As shown in the image.

[0088] Figure 9 This is a schematic diagram of a vertical color difference provided in Embodiment 3 of the present invention, with reference to... Figure 9 The transverse chromatic aberration of the longest and shortest wavelengths is controlled within ±6μm, indicating that the optical lens can effectively correct chromatic aberration at the edge of the field of view and the secondary spectrum of the entire image plane.

[0089] Note that the above description is merely a preferred embodiment of the present invention and the technical principles employed. Those skilled in the art will understand that the present invention is not limited to the specific embodiments described herein, and various obvious changes, readjustments, combinations, and substitutions can be made without departing from the scope of protection of the present invention. Therefore, although the present invention has been described in detail through the above embodiments, the present invention is not limited to the above embodiments, and may include many other equivalent embodiments without departing from the concept of the present invention, the scope of which is determined by the scope of the appended claims.

Claims

1. An ultra-wide-angle fixed-focus lens, characterized in that, It includes a first lens with negative optical power, a second lens with negative optical power, a third lens with positive optical power, a fourth lens with positive optical power, a fifth lens with negative optical power, a sixth lens with positive optical power, and a seventh lens with positive optical power, arranged sequentially from the object side to the image side along the optical axis. It also includes an aperture stop, which is located between the third lens and the fourth lens; the ultra-wide-angle fixed-focus lens has 7 lenses with optical power; The maximum field of view of the ultra-wide-angle fixed-focus lens is DFOV, the image height corresponding to the maximum field of view of the ultra-wide-angle fixed-focus lens is H, and the total focal length of the ultra-wide-angle fixed-focus lens is f, satisfying: ； ； The first lens has an optical power of φ1, the second lens has an optical power of φ2, the fourth lens has an optical power of φ4, the fifth lens has an optical power of φ5, and the seventh lens has an optical power of φ1. The optical power of the ultra-wide-angle fixed-focus lens is It meets the following conditions: ； ； ； The total length of the ultra-wide-angle fixed-focus lens is TTL, satisfying: 。 2. The ultra-wide-angle fixed-focus lens according to claim 1, characterized in that, The first lens and the third lens are glass spherical lenses, while the second lens, the fourth lens, the fifth lens, the sixth lens, and the seventh lens are plastic aspherical lenses.

3. The ultra-wide-angle fixed-focus lens according to claim 1, characterized in that, The object-side surface of the first lens protrudes towards the object side, and the image-side surface of the first lens is recessed towards the image side; The second lens and the fifth lens are biconcave lenses; The fourth lens is a biconvex lens; The object-side surface of the sixth lens is concave towards the object side, and the image-side surface of the sixth lens is convex towards the image side.

4. The ultra-wide-angle fixed-focus lens according to claim 3, characterized in that, The first lens has a refractive index of Nd1 and an Abbe number of Vd1, and the third lens has a refractive index of Nd3 and an Abbe number of Vd3, satisfying the following: ， ； And / or, , .

5. The ultra-wide-angle fixed-focus lens according to claim 1, characterized in that, The ultra-wide-angle fixed-focus lens has a back focal length of BFL, satisfying the following: 。 6. The ultra-wide-angle fixed-focus lens according to claim 1, characterized in that, The effective optical aperture of the seventh lens is D7, which satisfies: 。

Images