Machine vision optical system and camera module applied by same

Abstract

The invention provides a machine vision optical system and a camera module applying the same, the machine vision optical system is mainly composed of seven lenses, the object plane side of the first lens is a convex surface, the image plane side of the first lens is a concave surface, the focal power is negative, the object plane side of the second lens is a convex surface, the image plane side of the second lens is a concave surface, and the focal power is negative. The object plane side of the third lens is a concave surface, the image plane side of the third lens is a convex surface, and the focal power is positive; the object plane side and the image plane side of the fourth lens are convex surfaces, and the focal power is positive; the object plane side and the image plane side of the fifth lens are convex surfaces, and the focal power is positive; the object plane side and the image plane side of the sixth lens are concave surfaces, and the focal power is negative; the object plane side of the seventh lens is convex, the image plane side of the seventh lens is concave, the focal power is positive, the number of the lenses is reasonable, the structure is simple, the design requirements for the ultra-wide angle and miniaturization of the optical system are effectively met by reasonably distributing the focal power of the lenses, the high-pixel optical system for machine vision recognition has the design advantages of being high in pixel, high in resolution and ultra-wide angle, and the optical system is suitable for large-scale popularization and application. The structure is compact, processing and installation are convenient, and the imaging effect of equipment matched with the system is further improved.

Description

Technical Field

[0001] This application relates to the field of optical imaging, and particularly to a machine vision optical system and a camera module to which the same is applied. Background Art

[0002] Motion sensing games are popular in European and American countries and have gradually spread to Asian and European countries. The new motion sensing games can simulate three-dimensional scenes and control the actions of the characters in the game through the player's own body movements, enabling players to fully immerse themselves in the game and enjoy a green and healthy gaming experience. Due to the wide range of the target audience, they have broad market development prospects. The camera lens, as a core component of the motion sensing game device, also has broad development prospects. Therefore, how to provide a high-performance system with high pixel, ultra-wide angle, and miniaturization has become the goal pursued by everyone. Summary of the Invention

[0003] This application aims to provide a machine vision optical system with high pixel, ultra-wide angle, and miniaturization.

[0004] To achieve the above object, the present invention adopts the following technical solutions: A machine vision optical system is composed of a first lens, a second lens, a third lens, a fourth lens, a fifth lens, a sixth lens, and a seventh lens in sequence along the optical axis from the object plane to the image plane; The object plane side of the first lens is convex, and the image plane side is concave, and its optical power is negative; The object plane side of the second lens is convex, and the image plane side is concave, and its optical power is negative; The object plane side of the third lens is concave, and the image plane side is convex, and its optical power is positive; Both the object plane side and the image plane side of the fourth lens are convex, and its optical power is positive; Both the object plane side and the image plane side of the fifth lens are convex, and its optical power is positive; Both the object plane side and the image plane side of the sixth lens are concave, and its optical power is negative; The object plane side of the seventh lens is convex, and the image plane side is concave, and its optical power is positive.

[0005] Further, each lens of the optical system satisfies the following conditions: -6.5 mm < f1 < -2.5 mm; -16.3 mm < f2 < -10 mm; 50 mm < f3 < 130 mm; 3.50 mm < f4 < 6.5 mm; 1.5 mm < f5 < 3.5 mm; -3.5 mm < f6 < -1.5 mm; 13 mm < f7 < 30 mm; Wherein, f1 is the focal length of the first lens, f2 is the focal length of the second lens, f3 is the focal length of the third lens, f4 is the focal length of the fourth lens, f5 is the focal length of the fifth lens, f6 is the focal length of the sixth lens, and f7 is the focal length of the seventh lens.

[0006] Further, the radius of curvature R1 on the object side of the first lens satisfies: R1 < 11 mm.

[0007] Further, the optical system satisfies the following condition: TTL ≤ 15.9 mm; Wherein, TTL is the axial distance from the object side surface of the first lens to the imaging surface.

[0008] Further, each lens of the optical system satisfies the following conditions: 1.5 < Nd1 < 2.1, 20.00 < Vd1 < 50; 1.51 < Nd2 < 1.62, 52.50 < Vd2 < 58.00; 1.61 < Nd3 < 2.1, 16 < Vd3 < 35; 1.45 < Nd4 < 1.65, 53.5 < Vd4 < 70; 1.51 < Nd5 < 1.62, 52.50 < Vd5 < 58.00; 1.61 < Nd6 < 2.1, 16 < Vd6 < 35; 1.51 < Nd7 < 1.62, 52.50 < Vd7 < 58.00; Wherein, Nd1 is the refractive index of the first lens, Vd1 is the Abbe number of the first lens; Nd2 is the refractive index of the second lens, Vd2 is the Abbe number of the second lens; Nd3 is the refractive index of the third lens, Vd3 is the Abbe number of the third lens; Nd4 is the refractive index of the fourth lens, Vd4 is the Abbe number of the fourth lens; Nd5 is the refractive index of the fifth lens, Vd5 is the Abbe number of the fifth lens; Nd6 is the refractive index of the sixth lens, Vd6 is the Abbe number of the sixth lens; Nd7 is the refractive index of the seventh lens, Vd7 is the Abbe number of the seventh lens.

[0009] Further, the fourth lens is spherical.

[0010] Further, the FNO of the optical system satisfies: FNO ≤ 2.1.

[0011] Further, the full field of view FOV of the optical system satisfies: 185° ≤ FOV.

[0012] Further, the fifth lens and the sixth lens are cemented lenses.

[0013] Further, the refractive index Nd and Abbe number Vd of the two lenses of the glued lens satisfy: 1.51 < Nd5 < 1.62, 52.50 < Vd5 < 58.00; 1.61 < Nd6 < 2.1, 16 < Vd6 < 35.

[0014] On the other hand, the embodiment of the present application further provides an imaging module, which at least includes an optical lens, and the above-mentioned machine vision optical system is installed in the optical lens.

[0015] Compared with the prior art, the beneficial effects of the present application are as follows: The present invention provides a machine vision optical system and an imaging module to which it is applied, which is mainly composed of 7 lenses. The number of lenses is reasonable and the structure is simple. By reasonably distributing the optical power of the lenses, the design requirements of ultra-wide angle and miniaturization of the optical system are effectively met. The high-pixel machine vision recognition optical system configured in the present application has the advantages of high pixels, strong resolution, and ultra-wide angle design, with a compact structure, which is convenient for processing and installation, and further improves the imaging effect of the equipment equipped with this system. BRIEF DESCRIPTION OF THE DRAWINGS

[0016] In order to more clearly illustrate the technical solutions in the embodiments of the present application, the following will briefly introduce the drawings required for description in the embodiments.

[0017] Figure 1 It is a schematic structural diagram of the optical system or camera lens in Embodiment 1 of the present application; Figure 2 It is a field curvature and distortion curve diagram of the optical system or camera lens in Embodiment 1 of the present application; Figure 3 It is an MTF curve diagram of the optical system or camera lens in Embodiment 1 of the present application; Figure 4 It is a schematic structural diagram of the optical system or camera lens in Embodiment 2 of the present application; Figure 5 It is a field curvature and distortion curve diagram of the optical system or camera lens in Embodiment 2 of the present application; Figure 6 It is an MTF curve diagram of the optical system or camera lens in Embodiment 2 of the present application; Figure 7 It is a schematic structural diagram of the optical system or camera lens in Embodiment 3 of the present application; Figure 8 It is a field curvature and distortion curve diagram of the optical system or camera lens in Embodiment 3 of the present application; Figure 9 It is an MTF curve diagram of the optical system or imaging module in Embodiment 3 of the present application. DETAILED DESCRIPTION OF THE EMBODIMENTS

[0018] Such as Figures 1-9As shown in the figure, the present application provides a machine vision optical system, which is composed of a first lens E1, a second lens E2, a third lens E3, a fourth lens E4, a stop STO, a fifth lens E5, a sixth lens E6, and a seventh lens E7 in sequence along the optical axis from the object plane to the image plane; The object side of the first lens is convex, and the image side is concave, and its optical power is negative; The object side of the second lens is convex, and the image side is concave, and its optical power is negative; The object side of the third lens is concave, and the image side is convex, and its optical power is positive; Both the object side and the image side of the fourth lens are convex, and its optical power is positive; Both the object side and the image side of the fifth lens are convex, and its optical power is positive; Both the object side and the image side of the sixth lens are concave, and its optical power is negative; The object side of the seventh lens is convex, and the image side is concave, and its optical power is positive.

[0019] The optical system of the embodiment of the present application is mainly composed of 7 lenses. The number of lenses is reasonable and the structure is simple. By reasonably distributing the optical power of the lenses, the design requirements of ultra-wide angle and miniaturization of the optical system are effectively met. The optical system for high-pixel machine vision recognition configured in the present application has the advantages of high pixels, strong resolution, and ultra-wide angle design, with a compact structure, which is convenient for processing and installation, and further improves the imaging effect of the equipment equipped with this system.

[0020] Further, as a preferred embodiment of the present invention rather than a limitation, each lens of the optical system satisfies the following conditions: where f1 is the focal length of the first lens E1, f2 is the focal length of the second lens E2, f3 is the focal length of the third lens E3, f4 is the focal length of the fourth lens E4, f5 is the focal length of the fifth lens E5, f6 is the focal length of the sixth lens E6, and f7 is the focal length of the seventh lens E7; -6.5mm < f1 < -2.5 mm. By restricting the effective focal length of the first lens E1 within a reasonable range, the distortion of the system is controlled, so that the imaging center has a higher angular resolution; -16.3 mm < f2 < -10 mm; By restricting the effective focal length of the second lens E2 within a reasonable range, the lens aberration is optimized and the imaging quality is improved; 50 mm < f3 < 130 mm; By restricting the effective focal length of the third lens E3 within a reasonable range, the spherical aberration of the system is finely adjusted and controlled, thereby effectively improving the imaging quality of the system; 3.50 mm < f4 < 6.5 mm; By reasonably controlling the effective focal length of the fourth lens E4 within a reasonable range, the imaging quality of the system is effectively improved; 1.5 mm < f5 < 3.5 mm; By constraining the effective focal length of the fifth lens E5 within a reasonable range, the imaging quality is improved; -3.5 mm < f6 < -1.5 mm; By constraining the effective focal length of the sixth lens E6 within a reasonable range, the lens aberration is optimized and the resolution performance is improved; 13 mm < f7 < 30 mm; By constraining the effective focal length of the seventh lens E7 within a reasonable range, the lens aberration is optimized and the field curvature of the system is improved.

[0021] Furthermore, the refractive index Nd1 and Abbe number Vd1 of the first lens E1 satisfy: 1.5 < Nd1 < 2.1, 20.00 < Vd1 < 50. This design can effectively reduce chromatic aberration, optimize the lens aberration, and thus effectively improve the imaging quality of the system; Furthermore, the refractive index Nd2 and Abbe number Vd2 of the second lens E2 satisfy: 1.51 < Nd2 < 1.62, 52.50 < Vd2 < 58.00. This design can effectively reduce chromatic aberration, optimize the lens aberration, and thus effectively improve the imaging quality of the system; Furthermore, the refractive index Nd3 and Abbe number Vd3 of the third lens E3 satisfy: 1.61 < Nd3 < 2.1, 16 < Vd3 < 35. This design can effectively reduce chromatic aberration, optimize the lens aberration, and thus effectively improve the imaging quality of the system; Furthermore, the refractive index Nd4 and Abbe number Vd4 of the fourth lens E4 satisfy: 1.45 < Nd4 < 1.65, 53.5 < Vd4 < 70. This design can effectively reduce chromatic aberration, optimize the lens aberration, and thus effectively improve the imaging quality of the system; Furthermore, the refractive index Nd5 and Abbe number Vd5 of the fifth lens E5 satisfy: 1.51 < Nd5 < 1.62, 52.50 < Vd5 < 58.00. This design can effectively reduce chromatic aberration, optimize the lens aberration, and thus effectively improve the imaging quality of the system; Furthermore, the refractive index Nd6 and Abbe number Vd6 of the sixth lens E6 satisfy: 1.61 < Nd6 < 2.1, 16 < Vd6 < 35. This design can effectively reduce chromatic aberration, optimize the lens aberration, and thus effectively improve the imaging quality of the system; Furthermore, the refractive index Nd7 and Abbe number Vd7 of the seventh lens E7 satisfy: 1.51 < Nd7 < 1.62, 52.50 < Vd7 < 58.00. This design can effectively reduce chromatic aberration, optimize the lens aberration, and thus effectively improve the imaging quality of the system; Furthermore, as a preferred embodiment of the present invention rather than a limitation, the fourth lens E4 is spherical. By reasonably distributing the lens focal length, the lens aberration is optimized and the resolution performance is improved.

[0022] Further, as a preferred embodiment of the present invention rather than a limitation, the radius of curvature R1 of the object surface side of the first lens satisfies: R1 < 11 mm. By controlling the object surface side of the first lens E1, the total deflection angle of the object surface of the first lens 1 at the edge field of view can be reasonably controlled within a reasonable range.

[0023] Further, as a preferred embodiment of the present invention rather than a limitation, the optical system satisfies the following condition: TTL ≤ 15.9 mm. This design can reduce the overall optical length, miniaturize the lens, and make the miniaturized wide-angle lens more competitive in the market.

[0024] Further, as a preferred embodiment of the present invention rather than a limitation, the full field of view FOV of the optical system satisfies: 185° ≤ FOV and FNO ≤ 2.1, which is beneficial to expanding the field of view range of the lens and improving the light-gathering performance of the lens.

[0025] Further, as a preferred embodiment of the present invention rather than a limitation, the refractive index Nd and Abbe number Vd of the two lenses of the cemented lens satisfy: 1.51 < Nd5 < 1.62, 52.50 < Vd5 < 58.00; 1.61 < Nd6 < 2.1, 16 < Vd6 < 35. This design increases the difference between the refractive index and Abbe number of the lens, which can effectively reduce chromatic aberration.

[0026] Specifically, as a preferred embodiment of the present invention rather than a limitation, Figure 1 shows a schematic structural diagram of an optical imaging lens according to Embodiment 1 of the present application. As Figure 1 shown, the object surface side S1 of the first lens E1 is convex, the image surface side S2 is concave, and its optical power is negative; the object surface side S1 of the second lens E2 is convex, the image surface side S2 is concave, and its optical power is negative; the object surface side S1 of the third lens E3 is concave, the image surface side S2 is convex, and its optical power is positive; the object surface side S1 and the image surface side S2 of the fourth lens E4 are both convex, and its optical power is positive; the object surface side and the image surface side of the fifth lens E5 are both convex, and its optical power is positive; the object surface side and the image surface side of the sixth lens E6 are both concave, and its optical power is negative; the object surface side S1 of the seventh lens E7 is convex, the image surface side S2 is concave, and its optical power is positive; the filter E7; the light from the object sequentially passes through each surface and finally forms an image on the imaging surface.

[0027] Table 1 shows the surface type, radius of curvature, thickness and material of each lens of the optical imaging lens of Embodiment 1. Among them, the units of the radius of curvature and thickness are both millimeters (mm): Table 1: Basic parameters of the optical system of Embodiment 1

[0028] In Table 1 above, any one of the object side and the image side of the second lens E2, the third lens E3, the fifth lens E5, the sixth lens E6, and the seventh lens E7 is an aspherical surface. The surface shapes of the respective aspherical lenses can be defined by, but not limited to, the following aspherical formula:

[0029] Where x is the distance from the corresponding point on the aspherical surface to the plane tangent to the surface vertex, h is the distance from the corresponding point on the aspherical surface to the optical axis, c is the curvature of the aspherical vertex, k is the conic coefficient, and Ai is the coefficient corresponding to the i-th high-order term in the aspherical surface formula. Table 2 gives the conic coefficients and the high-order term coefficients A4, A6, A8, A10, A12, A14, A16, A20 for the respective aspherical surfaces that can be used in Example 1.

[0030] Table 2: Aspherical-related values of the lens surfaces in Example 1

[0031] Figure 2 Shows the astigmatism and distortion curves of the optical imaging lens of Example 1. Astigmatism represents the curvature of the meridional image plane and the sagittal image plane; distortion represents the distortion magnitude values corresponding to different image heights.

[0032] Figure 3 Shows the MTF curve of the optical imaging lens of Example 1, which represents the MTF values in the meridional direction and the sagittal direction of different fields of view.

[0033] From Figure 2 and Figure 3 it can be seen that the optical lens given in Example 1 can achieve good imaging quality.

[0034] Specifically, as a preferred implementation manner of the present invention rather than a limitation, Figure 4 Shows a schematic structural diagram of the optical imaging lens according to Embodiment 2 of the present application. As Figure 4 shown, the object surface side S1 of the first lens E1 is a convex surface, and the image surface side S2 is a concave surface, and its optical power is negative; the object surface side S1 of the second lens E2 is a convex surface, and the image surface side S2 is a concave surface, and its optical power is negative; the object surface side S1 of the third lens E3 is a concave surface, and the image surface side S2 is a convex surface, and its optical power is positive; the object surface side S1 and the image surface side S2 of the fourth lens E4 are both convex surfaces, and its optical power is positive; the object surface side and the image surface side of the fifth lens E5 are both convex surfaces, and its optical power is positive; the object surface side and the image surface side of the sixth lens E6 are both concave surfaces, and its optical power is negative; the object surface side S1 of the seventh lens E7 is convex, and the image surface side S2 is a concave surface, and its optical power is positive; a filter E7; the light from the object sequentially passes through each surface and finally forms an image on the imaging surface.

[0035] Table 3 shows the surface type, radius of curvature, thickness, and material of each lens of the optical imaging lens of Embodiment 2, where the units of the radius of curvature and thickness are both millimeters (mm): Table 3: Basic parameters of the optical system of Embodiment 2

[0036] In Table 3 above, for any one of the second lens E2, the fourth lens E4, the fifth lens E5, the sixth lens E6, and the seventh lens E7, both the object side and the image side are aspherical surfaces. The surface profiles of each aspherical lens can be defined by, but not limited to, the following aspherical formula:

[0037] Where x is the distance from the corresponding point on the aspherical surface to the plane tangent to the surface vertex, h is the distance from the corresponding point on the aspherical surface to the optical axis, c is the curvature of the aspherical vertex, k is the conic coefficient, and Ai is the coefficient corresponding to the i-th high-order term in the aspherical surface formula. Table 4 gives the conic coefficients and high-order term coefficients A4, A6, A8, A10, A12, A14, A16, A20 for each aspherical surface that can be used in Embodiment 2.

[0038] Table 4: Aspherical-related values of the lens surfaces in Embodiment 2

[0039] Figure 5 Shows the astigmatism and distortion curves of the optical imaging lens of Embodiment 2. Astigmatism represents the curvature of the meridional image plane and the sagittal image plane; distortion represents the distortion magnitude values corresponding to different image heights.

[0040] Figure 6 Shows the MTF curves of the optical imaging lens of Embodiment 2, which represent the MTF values in the meridional and sagittal directions of different fields of view.

[0041] From Figure 5 and Figure 6 it can be seen that the optical lens given in Embodiment 2 can achieve good imaging quality.

[0042] Specifically, as a preferred embodiment of the present invention rather than a limitation, Figure 7 shows a schematic structural diagram of the optical imaging lens according to Embodiment 3 of the present application, as Figure 4As shown, the object side S1 of the first lens E1 is convex, and the image side S2 is concave, with a negative optical power; the object side S1 of the second lens E2 is convex, and the image side S2 is concave, with a negative optical power; the object side S1 of the third lens E3 is concave, and the image side S2 is convex, with a positive optical power; the object side S1 and the image side S2 of the fourth lens E4 are both convex, with a positive optical power; the object side and the image side of the fifth lens E5 are both convex, with a positive optical power; the object side and the image side of the sixth lens E6 are both concave, with a negative optical power; the object side S1 of the seventh lens E7 is convex, and the image side S2 is concave, with a positive optical power; the filter E7; the light from the object sequentially passes through each surface and finally forms an image on the imaging surface.

[0043] Table 5 shows the surface types, curvature radii, thicknesses, and materials of the lenses of the optical imaging lens of Example 3. Among them, the units of the curvature radius and the thickness are both millimeters (mm): Table 5: Basic parameters of the optical system of Example 3

[0044] In the above Table 5, any one of the object side and the image side of the second lens E2, the fourth lens E4, the fifth lens E5, the sixth lens E6, and the seventh lens E7 is an aspherical surface. The surface profiles of the aspherical lenses can be defined by, but are not limited to, the following aspherical formula:

[0045] Among them, x is the distance from the corresponding point on the aspherical surface to the plane tangent to the surface vertex, h is the distance from the corresponding point on the aspherical surface to the optical axis, c is the curvature of the aspherical vertex, k is the conic coefficient, and Ai is the coefficient corresponding to the i-th high-order term in the aspherical surface profile formula. Table 6 gives the conic coefficients and the high-order term coefficients A4, A6, A8, A10, A12, A14, A16, A20 for the aspherical surfaces that can be used in Example 3.

[0046] Table 6: Aspherical-related values of the lens surfaces of Example 3

[0047] Figure 8 Shows the astigmatism and distortion curves of the optical imaging lens of Example 3. Astigmatism represents the curvature of the meridional image plane and the sagittal image plane; distortion represents the distortion magnitude values corresponding to different image heights.

[0048] Figure 9 Shows the MTF curves of the optical imaging lens of Example 3, which represent the MTF values in the meridional direction and the sagittal direction of different fields of view.

[0049] From Figure 8 and Figure 9It can be seen that the optical lens given in Embodiment 3 can achieve good imaging quality.

[0050] In Embodiments 1-3, the basic data are shown in Table 7 below: Table 7 Basic Data of Embodiments 1-3

[0051] A camera lens includes at least an optical lens, and the above-mentioned machine vision optical system is installed in the optical lens. An embodiment of the present invention provides a camera lens with a reasonable number of lens elements and a simple structure. By reasonably distributing the lens optical power, it effectively meets the design requirements of the optical system for ultra-wide angle and miniaturization. The high-pixel machine vision recognition optical system configured in this application has the advantages of high pixels, strong resolution, and ultra-wide angle design, with a compact structure, facilitating processing and installation, and further improving the imaging effect of the equipment equipped with this system.

[0052] The above are only the preferred embodiments of the present invention and are not intended to limit the present invention. Any modifications, equivalent replacements, and improvements made within the spirit and principles of the present invention shall be included in the protection scope of the present invention.

Claims

1. A machine vision optical system is composed of a first lens, a second lens, a third lens, a fourth lens, a fifth lens, a sixth lens, and a seventh lens in sequence along the optical axis from the object plane to the image plane, and is characterized in that: The object side of the first lens is convex, the image side is concave, and its optical power is negative; The object side of the second lens is convex, the image side is concave, and its optical power is negative; The object side of the third lens is concave, the image side is convex, and its optical power is positive; Both the object side and the image side of the fourth lens are convex, and its optical power is positive; Both the object side and the image side of the fifth lens are convex, and its optical power is positive; Both the object side and the image side of the sixth lens are concave, and its optical power is negative; The object side of the seventh lens is convex, the image side is concave, and its optical power is positive; The lenses of this optical system satisfy the following conditions: -6.5 mm < f1 < -2.5 mm; -16.3 mm < f2 < -10 mm; 50 mm < f3 < 130 mm; 3.50 mm < f4 < 6.5 mm; 1.5 mm < f5 < 3.5 mm; -3.5 mm < f6 < -1.5 mm; 13 mm < f7 < 30 mm; Among them, f1 is the focal length of the first lens, f2 is the focal length of the second lens, f3 is the focal length of the third lens, f4 is the focal length of the fourth lens, f5 is the focal length of the fifth lens, f6 is the focal length of the sixth lens, and f7 is the focal length of the seventh lens.

2. The machine vision optical system according to claim 1, wherein: The radius of curvature R1 of the object side of the first lens satisfies: R1 < 11mm.

3. The machine vision optical system according to claim 1, characterized in that: This optical system satisfies the following condition: TTL ≤ 15.9mm; Among them, TTL is the axial distance from the object side surface of the first lens to the imaging surface.

4. The machine vision optical system according to any one of claims 1-3, characterized in that: The lenses of this optical system satisfy the following conditions: 1.5 < Nd1 < 2.1, 20.00 < Vd1 < 50; 1.51 < Nd2 < 1.62, 52.50 < Vd2 < 58.00; 1.61 < Nd3 < 2.1, 16 < Vd3 < 35; 1.45 < Nd4 < 1.65, 53.5 < Vd4 < 70; 1.51 < Nd5 < 1.62, 52.50 < Vd5 < 58.00; 1.61 < Nd6 < 2.1, 16 < Vd6 < 35; 1.51 < Nd7 < 1.62, 52.50 < Vd7 < 58.00; Among them, Nd1 is the refractive index of the first lens, Vd1 is the Abbe number of the first lens; Nd2 is the refractive index of the second lens, Vd2 is the Abbe number of the second lens; Nd3 is the refractive index of the third lens, Vd3 is the Abbe number of the third lens; Nd4 is the refractive index of the fourth lens, Vd4 is the Abbe number of the fourth lens; Nd5 is the refractive index of the fifth lens, Vd5 is the Abbe number of the fifth lens; Nd6 is the refractive index of the sixth lens, Vd6 is the Abbe number of the sixth lens; Nd7 is the refractive index of the seventh lens, Vd7 is the Abbe number of the seventh lens.

5. The machine vision optical system according to any one of claims 1-3, characterized in that: The fourth lens is spherical.

6. The machine vision optical system according to any one of claims 1 to 3, characterized in that: The FNO of this optical system satisfies: FNO ≤ 2.

1.

7. The machine vision optical system according to any one of claims 1-3, characterized in that: The full field of view FOV of this optical system satisfies: 185° ≤ FOV.

8. The machine vision optical system according to any one of claims 1-3, characterized in that: The fifth lens and the sixth lens are cemented lenses.

9. The machine vision optical system according to claim 8, characterized in that: For the two lenses of the cemented lens, the refractive index Nd and Abbe number Vd satisfy: 1.51 < Nd5 < 1.62, 52.50 < Vd5 < 58.00; 1.61 < Nd6 < 2.1, 16 < Vd6 < 35.

10. An imaging module, at least comprising an optical lens, characterized in that: The machine vision optical system according to any one of claims 1-9 is installed in the optical lens.

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