An industrial lens

Abstract

The application discloses an industrial lens, which comprises a focusing lens group, a diaphragm and a fixed lens group arranged in sequence along an optical axis from an object plane to an image plane, the position of the focusing lens group is floatable along the optical axis, and the position of the fixed lens group is fixed; the focusing lens group comprises a first lens, a second lens, a third lens, a fourth lens, a fifth lens and a sixth lens arranged in sequence along the optical axis from the object plane to the image plane; and the fixed lens group comprises a seventh lens, an eighth lens, a ninth lens and a tenth lens arranged in sequence along the optical axis from the object plane to the image plane. The focusing lens group is moved along the optical axis to realize focusing at different object distances, the fixed lens group is fixed and immovable, the influence of focusing at different object distances on resolution can be reduced, and the image quality at each working distance is balanced. Moreover, the number of lenses contained in each lens group is reasonably arranged, which is beneficial to realize the industrial lens with high image quality and imaging performance.

Description

Technical Field

[0001] This invention relates to the field of optical device technology, and more particularly to an industrial lens. Background Technology

[0002] As a core vision component of industrial automation systems, industrial lenses play a crucial role as the "eyes of machines" in intelligent manufacturing. Their performance parameters directly constrain the accuracy and reliability of the entire vision inspection system, requiring compliance with the stringent standards specific to industrial scenarios. They must ensure continuous focusing over a wide object distance within a limited volume, minimize optical distortion, and maintain extremely high spatial resolution. However, existing industrial lenses generally suffer from problems such as a small focusing distance range, large distortion, and low edge resolution. The market urgently needs an industrial lens that can solve these technical problems to achieve the iterative upgrade of high-precision vision inspection equipment.

[0003] Therefore, developing an industrial lens that can provide a wider imaging range, less distortion, and higher resolution has become an urgent need for those skilled in the art. Summary of the Invention

[0004] This invention provides an industrial lens that achieves a wider imaging range, less distortion, and higher resolution.

[0005] This invention provides an industrial lens, comprising a focusing lens group, an aperture, and a fixed lens group arranged sequentially along the optical axis from the object plane to the image plane. The position of the focusing lens group can float along the optical axis, while the position of the fixed lens group is fixed.

[0006] The focusing lens group includes a first lens, a second lens, a third lens, a fourth lens, a fifth lens, and a sixth lens arranged sequentially along the optical axis from the object plane to the image plane;

[0007] The fixed lens group includes a seventh lens, an eighth lens, a ninth lens, and a tenth lens arranged sequentially along the optical axis from the object plane to the image plane.

[0008] Optionally, the first lens is a positive power lens, the second lens is a positive power lens, the third lens is a positive power lens, the fourth lens is a negative power lens, the fifth lens is a positive power lens, the sixth lens is a negative power lens, the seventh lens is a negative power lens, the eighth lens is a negative power lens, the ninth lens is a positive power lens, and the tenth lens is a positive power lens.

[0009] Optionally, the focal length of the first lens is F1, the focal length of the second lens is F2, the focal length of the third lens is F3, the focal length of the fourth lens is F4, the focal length of the fifth lens is F5, the focal length of the sixth lens is F6, the focal length of the seventh lens is F7, the focal length of the eighth lens is F8, the focal length of the ninth lens is F9, the focal length of the tenth lens is F10, and the total focal length of the industrial lens is F.

[0010] Among them, 1.921 <F1 / F<2.292,2.552 <F2 / F<3.431,1.010 <F3 / F<1.798,-1.165<F4 / F<-0.549,0.359 <F5 / F<0.494,-3.056 <F6 / F<-2.375,-0.868<F7 / F<-0.645,-0.466 <F8 / F<-0.389,0.761 <F9 / F<0.917,0.598<F10 / F<0.966。

[0011] Optionally, the third lens and the fourth lens are cemented together to form a first cemented lens group, and the fifth lens and the sixth lens are cemented together to form a second cemented lens group.

[0012] Optionally, the Abbe number of the third lens is VD3, the Abbe number of the fourth lens is VD4, the optical power of the third lens is Φ3, the optical power of the fourth lens is Φ4, and the optical power of the first cemented lens group is Φ3-4.

[0013] Of which, 45,000 <VD3<58.873,38.803<VD4<40.001,

[0014] -0.536≤1000*(Φ3 / VD3+Φ4 / VD4)≤-0.332, 10*|Φ3+Φ4-Φ3-4|<0.034.

[0015] Optionally, the Abbe number of the fifth lens is VD5, the Abbe number of the sixth lens is VD6, the optical power of the fifth lens is Φ5, the optical power of the sixth lens is Φ6, and the optical power of the second cemented lens group is Φ5-6;

[0016] Of which, 80,000 <VD5<92.968,14.997 <VD6<25.866,

[0017] 0.052≤1000*(Φ5 / VD5+Φ6 / VD6)≤0.286, 10*|Φ5+Φ6-Φ5-6|<0.104.

[0018] Optionally, the combined focal length of the first lens to the seventh lens is F1-7, and the combined focal length of the eighth lens to the tenth lens is F8-10;

[0019] Among them, 1.100 <F1-7 / F8-10 <1.373。

[0020] Optionally, the industrial lens has a back focal length of BFL, a total optical length of TTL, and a total focal length of F;

[0021] Among them, 0.240 <BFL / F<0.254,0.522<F / TTL<0.552。

[0022] Optionally, the first lens includes a first object-side surface near the object surface and a first image-side surface near the image surface, wherein the first object-side surface is convex and the first image-side surface is concave.

[0023] The second lens includes a second object-side surface near the object plane and a second image-side surface near the image plane, wherein the second object-side surface is convex and the second image-side surface is concave.

[0024] The third lens includes a third object-side surface near the object plane and a third image-side surface near the image plane. The third object-side surface is convex, and the third image-side surface is concave.

[0025] The fourth lens includes a fourth object-side surface near the object plane and a fourth image-side surface near the image plane. The fourth object-side surface is convex, and the fourth image-side surface is concave.

[0026] The fifth lens includes a fifth object-side surface near the object plane and a fifth image-side surface near the image plane. The fifth object-side surface is convex, and the fifth image-side surface is convex.

[0027] The sixth lens includes a sixth object-side surface near the object plane and a sixth image-side surface near the image plane. The sixth object-side surface is concave, and the sixth image-side surface is convex.

[0028] The seventh lens includes a seventh object-side surface near the object plane and a seventh image-side surface near the image plane. The seventh object-side surface is convex, and the seventh image-side surface is concave.

[0029] The eighth lens includes an eighth object-side surface near the object plane and an eighth image-side surface near the image plane. The eighth object-side surface is concave, and the eighth image-side surface is concave.

[0030] The ninth lens includes a ninth object-side surface near the object plane and a ninth image-side surface near the image plane. The ninth object-side surface is concave, and the ninth image-side surface is convex.

[0031] The tenth lens includes a tenth object-side surface near the object plane and a tenth image-side surface near the image plane. The tenth object-side surface is convex, and the tenth image-side surface is concave.

[0032] Optionally, the first lens to the tenth lens are all glass spherical lenses.

[0033] The industrial lens provided in this invention features a focusing lens group that can float along the optical axis, ensuring focusing at different working distances and achieving clear imaging at various object distances. Furthermore, the focusing lens group includes six floating focusing lenses, which guarantees a wide focusing object distance range and minimal distortion during focusing. Specifically, it can achieve focusing at object distances from 100mm to infinity with optical distortion less than or equal to 0.3%, ensuring a lens design with a larger imaging range and lower distortion. Furthermore, the fixed lens group remains stationary, reducing the impact of different focusing distances on resolution and ensuring balanced image quality at various working distances, thus enabling a higher-resolution lens design.

[0034] It should be understood that the description in this section is not intended to identify key or essential features of the embodiments of the present invention, nor is it intended to limit the scope of the invention. Other features of the invention will become readily apparent from the following description. Attached Figure Description

[0035] To more clearly illustrate the technical solutions in the embodiments of the present invention, the accompanying drawings used in the description of the embodiments will be briefly introduced below. Obviously, the accompanying drawings described below are only some embodiments of the present invention. For those skilled in the art, other drawings can be obtained based on these drawings without creative effort.

[0036] Figure 1 This is a schematic diagram of the structure of an industrial lens at the optimal object distance provided in Embodiment 1 of the present invention;

[0037] Figure 2 This is a schematic diagram of the light fan of an industrial lens at the optimal object distance, provided in Embodiment 1 of the present invention;

[0038] Figure 3 This is a schematic diagram of the field curvature distortion curve of an industrial lens at the optimal object distance, provided in Embodiment 1 of the present invention.

[0039] Figure 4 This is a schematic diagram of the MTF curve of an industrial lens at the optimal object distance, provided in Embodiment 1 of the present invention.

[0040] Figure 5This is a schematic diagram of the axial chromatic aberration curve of an industrial lens at the optimal object distance, provided in Embodiment 1 of the present invention.

[0041] Figure 6 This is a schematic diagram of the vertical chromatic aberration curve of an industrial lens at the optimal object distance, provided in Embodiment 1 of the present invention.

[0042] Figure 7 This is a schematic diagram of the structure of an industrial lens at the optimal object distance according to Embodiment 2 of the present invention;

[0043] Figure 8 This is a schematic diagram of the light fan of an industrial lens at the optimal object distance, provided in Embodiment 2 of the present invention;

[0044] Figure 9 This is a schematic diagram of the field curvature distortion curve of an industrial lens at the optimal object distance, provided in Embodiment 2 of the present invention.

[0045] Figure 10 This is a schematic diagram of the MTF curve of an industrial lens at the optimal object distance, provided in Embodiment 2 of the present invention.

[0046] Figure 11 This is a schematic diagram of the axial chromatic aberration curve of an industrial lens at the optimal object distance, provided in Embodiment 2 of the present invention.

[0047] Figure 12 This is a schematic diagram of the vertical chromatic aberration curve of an industrial lens at the optimal object distance, provided in Embodiment 2 of the present invention.

[0048] Figure 13 This is a schematic diagram of the structure of an industrial lens at the optimal object distance provided in Embodiment 3 of the present invention;

[0049] Figure 14 This is a schematic diagram of the light fan of an industrial lens at the optimal object distance, provided in Embodiment 3 of the present invention;

[0050] Figure 15 This is a schematic diagram of the field curvature distortion curve of an industrial lens at the optimal object distance, provided in Embodiment 3 of the present invention.

[0051] Figure 16 This is a schematic diagram of the MTF curve of an industrial lens at the optimal object distance, provided in Embodiment 3 of the present invention;

[0052] Figure 17 This is a schematic diagram of the axial chromatic aberration curve of an industrial lens at the optimal object distance, provided in Embodiment 3 of the present invention.

[0053] Figure 18 This is a schematic diagram of the vertical chromatic aberration curve of an industrial lens at the optimal object distance, provided in Embodiment 3 of the present invention. Detailed Implementation

[0054] To enable those skilled in the art to better understand the present invention, the technical solutions of the present invention will be clearly and completely described below with reference to the accompanying drawings of the embodiments of the present invention. Obviously, the described embodiments are only some embodiments of the present invention, and not all embodiments. Based on the embodiments of the present invention, all other embodiments obtained by those skilled in the art without creative effort should fall within the scope of protection of the present invention.

[0055] Example 1

[0056] Figure 1 This is a schematic diagram of the structure of an industrial lens at the optimal object distance according to Embodiment 1 of the present invention, as shown below. Figure 1 As shown, the industrial lens provided in this embodiment of the invention includes a focusing lens group S1 and a fixed lens group S2 arranged sequentially from the object plane to the image plane along the optical axis. The position of the focusing lens group S1 can float along the optical axis, while the position of the fixed lens group S2 is fixed. The focusing lens group S1 includes a first lens 101, a second lens 102, a third lens 103, a fourth lens 104, a fifth lens 105, and a sixth lens 106 arranged sequentially from the object plane to the image plane along the optical axis. The fixed lens group S2 includes a seventh lens 107, an eighth lens 108, a ninth lens 109, and a tenth lens 110 arranged sequentially from the object plane to the image plane along the optical axis.

[0057] Specifically, the industrial lens provided in this embodiment of the invention includes a focusing lens group S1 and a fixed lens group S2. The focusing lens group S1 can be understood as a lens group whose position changes, while the fixed lens group S2 can be understood as a lens whose position remains fixed. The focusing lens group S1 moves between the object plane and the fixed lens group S2. This positional change of the focusing lens group S1 ensures that the industrial lens can focus at different object distances, guaranteeing clear imaging at various object distances. Specifically, in close-object-distance focusing, the focusing lens group S1 is closer to the object plane; in infinity focusing, the focusing lens group S1 is closer to the fixed lens group S2. Furthermore, since the fixed lens group S2 remains stationary, the aberration changes caused by the forward and backward movement of the focusing lens group S1 at different working distances are mitigated by the fixed lens group S2, thus ensuring balanced image quality at each working distance and guaranteeing image quality.

[0058] Furthermore, the focusing lens group S1 includes a first lens 101, a second lens 102, a third lens 103, a fourth lens 104, a fifth lens 105, and a sixth lens 106. That is, the industrial lens includes six movable focusing lenses. In this way, focusing can be achieved by moving multiple lenses. Moreover, focusing by moving multiple lenses can achieve a large focusing distance range and small distortion during the focusing process. Specifically, it can achieve focusing at a distance of 100mm to infinity and optical distortion of less than or equal to 0.3%.

[0059] Furthermore, the fixed lens group S2 includes a seventh lens 107, an eighth lens 108, a ninth lens 109, and a tenth lens 110. That is, the industrial lens includes four fixed lenses. By fixing the four lenses, the influence of the moving focusing lens group S1 on aberrations is reduced, ensuring that the image quality at each working distance is balanced, guaranteeing imaging quality, and ensuring that a higher resolution lens design can be achieved.

[0060] Furthermore, the arrangement of ten lenses with optical power ensures that the number of lenses in the optical system is reasonable. Too many lenses will result in large lens sizes, while too few lenses will cause large aberrations due to each lens bearing a large optical power. This ensures that the optical system is miniaturized while maintaining small imaging aberrations and high imaging quality.

[0061] Further reference Figure 1 As shown, the industrial lens of this embodiment may further include an aperture stop STO and a filter 111. The aperture stop STO is disposed in the optical path between the focusing lens group S1 and the fixed lens group S2, and the filter 111 is disposed in the optical path between the tenth lens 110 and the image plane. The aperture stop STO can adjust the propagation direction of the light beam, which is beneficial for improving image quality. Furthermore, in this industrial lens, the aperture stop STO, disposed in the optical system, can limit the beam size and control the amount of light transmitted through the lens, thus facilitating a reduction in aperture value and achieving a large aperture. The filter 111 can filter out stray light, improving the imaging effect.

[0062] Furthermore, the optical lens provided in this embodiment of the invention may also include a protective glass and an imaging sensor. The protective glass may be disposed on the image-side of the filter, and the imaging sensor may be disposed on the image-side of the protective glass. The optical system is protected by the protective glass, and the image is acquired by the imaging sensor, thus enabling the optical system to perform its normal imaging function.

[0063] In summary, the industrial lens provided by this invention features a focusing lens group that can float along the optical axis, ensuring focusing at different working distances and achieving clear imaging at different object distances. Furthermore, the fixed lens group remains stationary, thus reducing the impact of focusing at different object distances on resolution and ensuring balanced image quality across all working distances. Moreover, by rationally setting the number of lenses in the focusing lens group S1 and the fixed lens group S2, a lens design with a larger imaging range, lower distortion, and higher resolution can be achieved, guaranteeing the imaging quality of the industrial lens.

[0064] Based on the above embodiments, the first lens 101 is a positive power lens, the second lens 102 is a positive power lens, the third lens 103 is a positive power lens, the fourth lens 104 is a negative power lens, the fifth lens 105 is a positive power lens, the sixth lens 106 is a negative power lens, the seventh lens 107 is a negative power lens, the eighth lens 108 is a negative power lens, the ninth lens 109 is a positive power lens, and the tenth lens 110 is a positive power lens.

[0065] Specifically, optical power is equal to the difference between the convergence of the beam at the image plane and the convergence of the beam at the object plane, characterizing the ability of an optical system to deflect light. The larger the absolute value of the optical power, the stronger the bending ability of light; the smaller the absolute value, the weaker the bending ability. When the optical power is positive, the refraction of light is converging; when the optical power is negative, the refraction of light is diverging. Optical power can be used to characterize a single refractive surface of a lens (i.e., a surface of the lens), a single lens, or a system formed by multiple lenses (i.e., a lens group). In this embodiment of the invention, the first lens 101, the second lens 102, and the third lens 103 are all positive optical power lenses. Their positive optical power setting can significantly correct the edge aberrations of the optical imaging system, thereby improving the imaging resolution of the optical system. The fourth lens 104 is a negative optical power lens. Its negative optical power setting can effectively deflect the outgoing light, which is beneficial for achieving a large image plane design. The fifth lens 105 is a positive power lens, the sixth lens 106, the seventh lens 107 and the eighth lens 108 are all negative power lenses, and the ninth lens 109 and the tenth lens 110 are all positive power lenses. The combination of positive and negative power is beneficial for aberration correction.

[0066] On the basis of the above embodiments, the focal length of the first lens 101 is F1, the focal length of the second lens 102 is F2, the focal length of the third lens 103 is F3, the focal length of the fourth lens 104 is F4, the focal length of the fifth lens 105 is F5, the focal length of the sixth lens 106 is F6, the focal length of the seventh lens 107 is F7, the focal length of the eighth lens 108 is F8, the focal length of the ninth lens 109 is F9, the focal length of the tenth lens 110 is F10, and the total focal length of the industrial lens is F. Among them, 1.921 < F1 / F < 2.292, 2.552 < F2 / F < 3.431, 1.010 < F3 / F < 1.798, -1.165 < F4 / F < -0.549, 0.359 < F5 / F < 0.494, -3.056 < F6 / F < -2.375, -0.868 < F7 / F < -0.645, -0.466 < F8 / F < -0.389, 0.761 < F9 / F < 0.917, 0.598 < F10 / F < 0.966. Reasonably distributing the focal lengths of the lenses under the requirements of the above focal length relationship is beneficial to the normal convergence of light rays by the lens, reducing the light propagation height inside the lens, reducing the aberration generated by it, making the light ray trends and refraction angles on both sides of the object image consistent or close, and then by adjusting the air gaps between different lenses and optimizing the lens apertures, meeting the above relationships is beneficial to achieving the characteristics of small distortion, small chromatic aberration and low field curvature.

[0067] On the basis of the above embodiments, the third lens 103 and the fourth lens 104 are adhesively bonded to form a first adhesive lens group, and the fifth lens 105 and the sixth lens 106 are adhesively bonded to form a second adhesive lens group.

[0068] Specifically, the adhesive bonding of different lenses can be understood as the image side of the previous lens in the optical path being in contact with the object side of the subsequent lens, having the same surface shape. As Figure 1 shown, the adhesive bonding of the third lens 103 and the fourth lens 104 can be understood as the image side of the third lens 103 being in contact with the object side of the fourth lens 104. The adhesive bonding of the fifth lens 105 and the sixth lens 106 can be understood as the image side of the fifth lens 105 being in contact with the object side of the sixth lens 106. That is, the focusing lens group S1 includes two pairs of adhesively bonded lens groups.

[0069] The adhesive lens can be used to minimize or eliminate chromatic aberration. Using the adhesive lens in an industrial lens can improve the image quality and reduce the reflection loss of light energy, thereby enhancing the clarity of the lens imaging. In addition, the adhesive bonding of the lenses omits the air gap between the two lenses, making the overall optical system compact and meeting the requirements of system miniaturization. Moreover, the adhesive bonding of the lenses will reduce the sensitivity of tolerance problems such as tilt / eccentricity generated during the assembly of the lens unit.

[0070] Furthermore, the third lens 103 and the fourth lens 104 can be bonded together with adhesive; the fifth lens 105 and the sixth lens 106 can also be bonded together with adhesive. This embodiment of the invention does not limit the method of bonding different lenses together.

[0071] Based on the above embodiment, the Abbe number of the third lens 103 is VD3, the Abbe number of the fourth lens 104 is VD4, the optical power of the third lens 103 is Φ3, the optical power of the fourth lens 104 is Φ4, and the optical power of the first cemented lens group is Φ3-4; wherein, 45.000 <VD3<58.873,38.803<VD4<40.001,-0.536≤1000*(Φ3 / VD3+Φ4 / VD4)≤-0.332,10*|Φ3+Φ4-Φ3-4|<0.034。

[0072] Specifically, the Abbe number represents the index of the medium's dispersion capability; the larger the Abbe constant, the less dispersion. By reasonably setting the Abbe numbers of the third lens 103 and the fourth lens 104, and setting -0.536≤1000*(Φ3 / VD3+Φ4 / VD4)≤-0.332 and 10*|Φ3+Φ4-Φ3-4|<0.034, it is beneficial to correct axial and transverse chromatic aberration, thereby obtaining higher resolution and better performance.

[0073] Based on the above embodiment, the Abbe number of the fifth lens is VD5, the Abbe number of the sixth lens is VD6, the optical power of the fifth lens is Φ5, the optical power of the sixth lens is Φ6, and the optical power of the second cemented lens group is Φ5-6; wherein, 80.000 <VD5<92.968,14.997 <VD6<25.866,

[0074] 0.052≤1000*(Φ5 / VD5+Φ6 / VD6)≤0.286, 10*|Φ5+Φ6-Φ5-6|<0.104. By reasonably setting the Abbe number of the fifth lens 105 and the sixth lens 106, and setting 0.052≤1000*(Φ5 / VD5+Φ6 / VD6)≤0.286, 10*|Φ5+Φ6-Φ5-6|<0.104, it is beneficial to correct axial chromatic aberration and transverse chromatic aberration, thereby obtaining higher resolution and better performance.

[0075] Based on the above embodiments, the combined focal length of the first to seventh lenses is F1-7, and the combined focal length of the eighth to tenth lenses is F8-10; wherein, 1.100 <F1-7 / F8-10 <1.373。

[0076] Specifically, the system distortion is the sum of the distortions generated by all lenses. The distortion is balanced by restricting the optical power of each lens. The combined focal length of the first lens to the seventh lens is denoted as F1-7, and the combined focal length of the eighth lens to the tenth lens is denoted as F8-10. Meeting the above conditions can balance the lens distortion.

[0077] Based on the above embodiments, the back focal length of the industrial lens is BFL, the overall optical length is TTL, and the total focal length is F. Among them, 0.240 < BFL / F < 0.254, and 0.522 < F / TTL < 0.552. Setting the back focal length BFL, the overall optical length TTL, and the total focal length F of the industrial lens to meet the above limitations is beneficial to compress the overall length of the lens and ensure the realization of a miniaturized lens design.

[0078] Based on the above embodiments, the first lens 101 includes a first object side surface close to the object surface side and a first image side surface close to the image surface side. The first object side surface is a convex surface, and the first image side surface is a concave surface; the second lens 102 includes a second object side surface close to the object surface side and a second image side surface close to the image surface side. The second object side surface is a convex surface, and the second image side surface is a concave surface; the third lens 103 includes a third object side surface close to the object surface side and a third image side surface close to the image surface side. The third object side surface is a convex surface, and the third image side surface is a concave surface; the fourth lens 104 includes a fourth object side surface close to the object surface side and a fourth image side surface close to the image surface side. The fourth object side surface is a convex surface, and the fourth image side surface is a concave surface; the fifth lens 105 includes a fifth object side surface close to the object surface side and a fifth image side surface close to the image surface side. The fifth object side surface is a convex surface, and the fifth image side surface is a convex surface; the sixth lens 106 includes a sixth object side surface close to the object surface side and a sixth image side surface close to the image surface side. The sixth object side surface is a concave surface, and the sixth image side surface is a convex surface; the seventh lens 107 includes a seventh object side surface close to the object surface side and a seventh image side surface close to the image surface side. The seventh object side surface is a convex surface, and the seventh image side surface is a concave surface; the eighth lens 108 includes an eighth object side surface close to the object surface side and an eighth image side surface close to the image surface side. The eighth object side surface is a concave surface, and the eighth image side surface is a concave surface; the ninth lens 109 includes a ninth object side surface close to the object surface side and a ninth image side surface close to the image surface side. The ninth object side surface is a concave surface, and the ninth image side surface is a convex surface; the tenth lens 110 includes a tenth object side surface close to the object surface side and a tenth image side surface close to the image surface side. The tenth object side surface is a convex surface, and the tenth image side surface is a concave surface.

[0079] Specifically, the object side surface of the lens can be understood as the surface of the lens close to the object surface side, and the image side surface of the lens can be understood as the surface of the lens close to the image surface side.

[0080] The object side of the first lens 101 is convex, and the image side is concave. This can be understood as the object side of the first lens 101 convex towards the object surface near the optical axis, and the image side is concave towards the image surface near the optical axis. In other words, the first lens 101 is a lens with a convex-concave structure.

[0081] The object side of the second lens 102 is convex, and the image side is concave. This can be understood as the object side of the second lens 102 convex towards the object surface at the near-optical axis position, and the image side concave towards the image surface at the near-optical axis position. In other words, the second lens 102 is a lens with a convex-concave structure.

[0082] The object side of the third lens 103 is convex, and the image side is concave. This can be understood as the object side of the third lens 103 convex towards the object surface near the optical axis, and the image side concave towards the image surface near the optical axis. In other words, the third lens 103 is a lens with a convex-concave structure.

[0083] The object side of the fourth lens 104 is convex, and the image side is concave. This can be understood as the object side of the fourth lens 104 convex towards the object surface near the optical axis, and the image side concave towards the image surface near the optical axis. In other words, the fourth lens 104 is a lens with a convex-concave structure.

[0084] The object-side surface of the fifth lens 105 is convex, and the image-side surface is also convex. This can be understood as the object-side surface of the fifth lens 105 convex towards the object surface near the optical axis, and the image-side surface convex towards the image surface near the optical axis. In other words, the fifth lens 105 is a lens with a biconvex structure.

[0085] The object-side surface of the sixth lens 106 is concave, and the image-side surface is convex. This can be understood as the object-side surface of the sixth lens 106 being concave towards the object surface near the optical axis, and the image-side surface being convex towards the image surface near the optical axis. In other words, the sixth lens 106 can be a lens with a concave-convex structure.

[0086] The object-side surface of the seventh lens 107 is convex, and the image-side surface is concave. This can be understood as the object-side surface of the seventh lens 107 convex towards the object surface near the optical axis, and the image-side surface concave towards the image surface near the optical axis. In other words, the seventh lens 107 is a lens with a convex-concave structure.

[0087] The object side of the eighth lens 108 is concave, and the image side is concave. This can be understood as the object side of the eighth lens 108 being concave towards the object plane near the optical axis, and the image side being concave towards the image plane near the optical axis. In other words, the eighth lens 108 is a lens with a double concave structure.

[0088] The object-side surface of the ninth lens 109 is concave, and the image-side surface is convex. This can be understood as the object-side surface of the ninth lens 109 being concave towards the object surface near the optical axis, and the image-side surface being convex towards the image surface near the optical axis. In other words, the ninth lens 109 is a lens with a concave-convex structure.

[0089] The object-side surface of the tenth lens 110 is convex, and the image-side surface is concave. This can be understood as the object-side surface of the tenth lens 110 convex towards the object surface near the optical axis, and the image-side surface concave towards the image surface near the optical axis. In other words, the tenth lens 110 is a lens with a convex-concave structure.

[0090] By properly setting the concave and convex surfaces of each lens, the light emission angle of each lens can be modulated. Furthermore, for cemented lenses, it is possible to cement at least two adjacent lenses together. On the other hand, it can also reduce the spacing between adjacent lenses, which is beneficial for achieving small-volume industrial lens designs.

[0091] Based on the above embodiments, the first lens 101 to the tenth lens 110 are all glass spherical lenses.

[0092] Spherical lenses are characterized by a constant curvature from the center to the periphery, ensuring a simple lens setup. Furthermore, due to the low coefficient of thermal expansion and good stability of glass lenses, spherical glass lenses exhibit even greater thermal stability, guaranteeing good resolving power over a wide temperature range when handling higher optical powers. Moreover, the range of glass materials available is wider, with relatively free selection of refractive index and Abbe number, allowing for better control of higher aberrations and chromatic aberration, meeting the needs of use under complex conditions. Therefore, in the industrial lens provided by this embodiment, the first lens 101, second lens 102, third lens 103, fourth lens 104, fifth lens 105, sixth lens 106, seventh lens 107, eighth lens 108, ninth lens 109, and tenth lens 110 are all glass spherical lenses, ensuring stable performance and good resolving power over a wide temperature range, meeting the needs of use in high and low temperature environments.

[0093] As a feasible implementation method, the parameters of each lens in the industrial lens will be explained next.

[0094] Table 1. Optical design values ​​for an industrial lens in Example 1

[0095]

[0096] Table 2 Design values ​​of optical physical parameters for industrial lenses

[0097]

[0098] The surface numbers in Table 2 are assigned according to the surface sequence of each lens. "0" represents the object surface, "1" represents the object-side surface of the first lens, "2" represents the image-side surface of the first lens, and so on. The radius of curvature represents the degree of curvature of the corresponding lens surface; a positive value indicates that the surface bends towards the image surface, and a negative value indicates that the surface bends towards the object surface. "INF" indicates that the surface is flat and the radius of curvature is infinite. The thickness represents the central axial distance between the current surface and the next surface. The refractive index represents the ability of the material between the current surface and the next surface to deflect light. A blank space indicates that the current location is air, with a refractive index of 1. The Abbe number represents the dispersion characteristics of the material between the current surface and the next surface. Half-aperture indicates half the aperture size of the current surface.

[0099] Table 3. One design value for focus interval

[0100]

[0101] This embodiment satisfies the following parameters:

[0102] Focal length: 49.953mm; image f-number: 2.816; image plane Φ11.82mm.

[0103] Figure 2 This is a schematic diagram of the beam fan of an industrial lens at the optimal object distance, provided in Embodiment 1 of the present invention. The beam fan diagram is one of the most commonly used evaluation methods in modern optical design. The horizontal axis represents the beam aperture, and the vertical axis represents the transverse aberration. The ideal curve is a straight line coinciding with the horizontal axis, indicating that all rays converge at the same point on the image plane. The interval corresponding to the vertical axis of the curve is the maximum dispersion range of the beam on the ideal image plane. The beam fan diagram can reflect not only monochromatic aberrations of different wavelengths but also the magnitude of transverse chromatic aberration. Figure 2 It can be seen that the system closely approximates the horizontal axis at each wavelength in each field of view, indicating that the transverse aberration of each wavelength is well corrected. At the same time, there is no obvious dispersion of each wavelength, indicating that the chromatic aberration of the system is also well corrected, thus ensuring that the optical system can achieve the high-resolution imaging requirements.

[0104] Figure 3 This is a schematic diagram of the field curvature distortion curve of an industrial lens at the optimal object distance, provided in Embodiment 1 of the present invention. In the coordinate system on the left side of the figure, the horizontal axis represents the magnitude of the field curvature in mm; the vertical axis represents the normalized image height, which has no unit; where T represents the meridion and S represents the sagitta; Figure 3 It can be seen that the lens provided in this embodiment effectively controls field curvature, meaning that during imaging, the difference in image quality between the center and the periphery is small, resulting in good consistency. In the coordinate system on the right, the horizontal axis represents the magnitude of distortion, expressed as a percentage (%), and the vertical axis represents the normalized image height, which has no unit. Figure 3As can be seen, the distortion of the lens provided in this embodiment has been well corrected, with optical distortion less than ±0.3%.

[0105] Figure 4 This is a schematic diagram of the MTF curve of an industrial lens at the optimal object distance provided in Embodiment 1 of the present invention. The image quality of the lens of the present invention at 250pl / mm from the center field of view to the edge field of view is higher than 0.2 MTF, and the imaging has excellent resolution.

[0106] Figure 5 This is a schematic diagram of the axial chromatic aberration curve of an industrial lens at the optimal object distance, provided in Embodiment 1 of the present invention. In the figure, the vertical direction represents the normalized 0-field pupil plane, where 0 represents the pupil center, and the vertical vertex represents the pupil vertex. The horizontal direction represents the axial chromatic aberration at different wavelengths (specifically 460nm, 530nm, and 620nm), in millimeters (mm). As shown in the figure, the axial chromatic aberration of the entire pupil of the lens of the present invention is less than 25μm, resulting in excellent image sharpness.

[0107] Figure 6 This is a schematic diagram of the transverse chromatic aberration curve of an industrial lens at the optimal object distance, provided in Embodiment 1 of the present invention. In the figure, the vertical direction represents the field of view angle, 0 represents the field of view angle incident parallel to the optical axis, and the vertex of the vertical direction represents the maximum half field of view angle. As shown in the figure, at each wavelength of the system (specifically 460nm, 530nm, and 620nm), the transverse chromatic aberration from the center field of view to the edge field of view of the lens is less than 0.5μm, resulting in higher imaging quality.

[0108] In summary, the industrial lens provided in this embodiment of the invention adopts an all-glass 10G structure. Through the combination of lens materials and the reasonable allocation of the optical power of each element, an industrial lens design that can take into account wide object distance, high resolution, and low optical distortion is achieved. It can achieve focusing at an object distance of 100mm to infinity, with a focal length of 49.953mm, an image-side F number of 2.816, a target surface of Φ11.82mm, and optical distortion ≤0.3%.

[0109] Example 2

[0110] Figure 7 This is a schematic diagram of the structure of an industrial lens at the optimal object distance according to Embodiment 2 of the present invention, as shown below. Figure 7As shown, the industrial lens provided in Embodiment 2 of the present invention includes a focusing lens group S1 and a fixed lens group S2 arranged sequentially from the object plane to the image plane along the optical axis. The position of the focusing lens group S1 can float along the optical axis, while the position of the fixed lens group S2 is fixed. The focusing lens group S1 includes a first lens 101, a second lens 102, a third lens 103, a fourth lens 104, a fifth lens 105, and a sixth lens 106 arranged sequentially from the object plane to the image plane along the optical axis. The fixed lens group S2 includes a seventh lens 107, an eighth lens 108, a ninth lens 109, and a tenth lens 110 arranged sequentially from the object plane to the image plane along the optical axis.

[0111] Other parameters are the same as in Example 1, and will not be repeated here.

[0112] As another feasible implementation method, the specific parameters in industrial lenses are explained below.

[0113] Table 4. Optical design values ​​for an industrial lens in Example 2

[0114]

[0115] Table 5 Design values ​​of optical physical parameters for industrial lenses

[0116]

[0117] The surface numbers in Table 5 are assigned according to the surface sequence of each lens. "0" represents the object surface, "1" represents the object-side surface of the first lens, "2" represents the image-side surface of the first lens, and so on. The radius of curvature represents the degree of curvature of the corresponding lens surface; a positive value indicates that the surface bends towards the image surface, and a negative value indicates that the surface bends towards the object surface. "INF" indicates that the surface is flat and the radius of curvature is infinite. The thickness represents the central axial distance between the current surface and the next surface. The refractive index represents the ability of the material between the current surface and the next surface to deflect light. A blank space indicates that the current location is air, with a refractive index of 1. The Abbe number represents the dispersion characteristics of the material between the current surface and the next surface. Half-aperture indicates half the aperture size of the current surface.

[0118] Table 6. One design value for focus interval

[0119]

[0120] This embodiment satisfies the following parameters:

[0121] Focal length: 47.997mm; image f-number: 2.898; image plane Φ11.816mm.

[0122] Figure 8This is a schematic diagram of the light fan of an industrial lens at the optimal object distance, provided in Embodiment 2 of the present invention. The light fan diagram is one of the most commonly used evaluation methods in modern optical design. The horizontal axis represents the beam aperture, and the vertical axis represents the transverse aberration. The ideal curve is a straight line coinciding with the horizontal axis, indicating that all light rays converge at the same point on the image plane. The interval corresponding to the vertical axis of the curve is the maximum dispersion range of the beam on the ideal image plane. The light fan diagram can reflect not only monochromatic aberrations of different wavelengths but also the magnitude of transverse chromatic aberration. Figure 8 It can be seen that the system closely approximates the horizontal axis at each wavelength in each field of view, indicating that the transverse aberration of each wavelength is well corrected. At the same time, there is no obvious dispersion of each wavelength, indicating that the chromatic aberration of the system is also well corrected, thus ensuring that the optical system can achieve the high-resolution imaging requirements.

[0123] Figure 9 This is a schematic diagram of the field curvature distortion curve of an industrial lens at the optimal object distance, provided in Embodiment 2 of the present invention. In the coordinate system on the left side of the figure, the horizontal axis represents the magnitude of the field curvature, in mm; the vertical axis represents the normalized image height, which has no unit; where T represents the meridion and S represents the sagitta; Figure 9 It can be seen that the lens provided in this embodiment effectively controls field curvature, meaning that during imaging, the difference in image quality between the center and the periphery is small, resulting in good consistency. In the coordinate system on the right, the horizontal axis represents the magnitude of distortion, expressed as a percentage (%), and the vertical axis represents the normalized image height, which has no unit. Figure 9 As can be seen, the distortion of the lens provided in this embodiment has been well corrected, with optical distortion less than ±0.3%.

[0124] Figure 10 This is a schematic diagram of the MTF curve of an industrial lens at the optimal object distance provided in Embodiment 2 of the present invention. The image quality of the lens of the present invention at 250pl / mm from the center field of view to the edge field of view is higher than 0.2 MTF, and the imaging has excellent resolution.

[0125] Figure 11 This is a schematic diagram of the axial chromatic aberration curve of an industrial lens at the optimal object distance, provided in Embodiment 2 of the present invention. In the figure, the vertical direction represents the normalized 0-field pupil plane, where 0 represents the pupil center, and the vertical vertex represents the pupil vertex. The horizontal direction represents the axial chromatic aberration at different wavelengths (specifically 460nm, 530nm, and 620nm), in millimeters (mm). As shown in the figure, the axial chromatic aberration of the entire pupil of the lens of the present invention is less than 25μm, resulting in excellent image sharpness.

[0126] Figure 12This is a schematic diagram of the transverse chromatic aberration curve of an industrial lens at the optimal object distance, provided in Embodiment 2 of the present invention. In the figure, the vertical direction represents the field of view angle, 0 represents the field of view angle incident parallel to the optical axis, and the vertex of the vertical direction represents the maximum half field of view angle. As shown in the figure, at each wavelength of the system (specifically 460nm, 530nm, and 620nm), the transverse chromatic aberration from the center field of view to the edge field of view of the lens is less than 0.5μm, resulting in higher imaging quality.

[0127] In summary, the industrial lens provided in this embodiment of the invention adopts an all-glass 10G structure. Through the combination of lens materials and the reasonable allocation of the optical power of each component, an industrial lens design that can take into account wide object distance, high resolution, and low optical distortion is achieved. It can achieve focusing at an object distance of 100mm to infinity, with a focal length of 47.997mm, an image-side F number of 2.898, a target surface of Φ11.816mm, and optical distortion ≤0.3%.

[0128] Example 3

[0129] Figure 13 This is a schematic diagram of the structure of an industrial lens at the optimal object distance according to Embodiment 3 of the present invention, as shown below. Figure 13 As shown, the industrial lens provided in Embodiment 3 of the present invention includes a focusing lens group S1 and a fixed lens group S2 arranged sequentially from the object plane to the image plane along the optical axis. The position of the focusing lens group S1 can float along the optical axis, while the position of the fixed lens group S2 is fixed. The focusing lens group S1 includes a first lens 101, a second lens 102, a third lens 103, a fourth lens 104, a fifth lens 105, and a sixth lens 106 arranged sequentially from the object plane to the image plane along the optical axis. The fixed lens group S2 includes a seventh lens 107, an eighth lens 108, a ninth lens 109, and a tenth lens 110 arranged sequentially from the object plane to the image plane along the optical axis.

[0130] Other parameters are the same as in Example 1, and will not be repeated here.

[0131] As another feasible implementation method, the specific parameters in industrial lenses are explained below.

[0132] Table 7. Optical design values ​​for an industrial lens in Example 3

[0133]

[0134] Table 8 Design values ​​of optical physical parameters for industrial lenses

[0135]

[0136] The surface numbers in Table 8 are assigned according to the surface sequence of each lens. "0" represents the object surface, "1" represents the object-side surface of the first lens, "2" represents the image-side surface of the first lens, and so on. The radius of curvature represents the degree of curvature of the corresponding lens surface; a positive value indicates that the surface bends towards the image surface, and a negative value indicates that the surface bends towards the object surface. "INF" indicates that the surface is flat and the radius of curvature is infinite. The thickness represents the central axial distance between the current surface and the next surface. The refractive index represents the ability of the material between the current surface and the next surface to deflect light. A blank space indicates that the current location is air, with a refractive index of 1. The Abbe number represents the dispersion characteristics of the material between the current surface and the next surface. Half-aperture indicates half the aperture size of the current surface.

[0137] Table 9. One design value for focus interval

[0138]

[0139] This embodiment satisfies the following parameters:

[0140] Focal length: 47.998mm; f-number: 2.804; image plane Φ11.814mm.

[0141] Figure 14 This is a schematic diagram of the beam fan of an industrial lens at the optimal object distance, provided in Embodiment 3 of the present invention. The beam fan diagram is one of the most commonly used evaluation methods in modern optical design. The horizontal axis represents the beam aperture, and the vertical axis represents the transverse aberration. The ideal curve is a straight line coinciding with the horizontal axis, indicating that all rays converge at the same point on the image plane. The interval corresponding to the vertical axis of the curve is the maximum dispersion range of the beam on the ideal image plane. The beam fan diagram can reflect not only monochromatic aberrations of different wavelengths but also the magnitude of transverse chromatic aberration. Figure 14 It can be seen that the system closely approximates the horizontal axis at each wavelength in each field of view, indicating that the transverse aberration of each wavelength is well corrected. At the same time, there is no obvious dispersion of each wavelength, indicating that the chromatic aberration of the system is also well corrected, thus ensuring that the optical system can achieve the high-resolution imaging requirements.

[0142] Figure 15 This is a schematic diagram of the field curvature distortion curve of an industrial lens at the optimal object distance, provided in Embodiment 3 of the present invention. In the coordinate system on the left side of the figure, the horizontal axis represents the magnitude of the field curvature, in mm; the vertical axis represents the normalized image height, which has no unit; where T represents the meridion and S represents the sagitta; Figure 15 It can be seen that the lens provided in this embodiment effectively controls field curvature, meaning that during imaging, the difference in image quality between the center and the periphery is small, resulting in good consistency. In the coordinate system on the right, the horizontal axis represents the magnitude of distortion, expressed as a percentage (%), and the vertical axis represents the normalized image height, which has no unit. Figure 9As can be seen, the distortion of the lens provided in this embodiment has been well corrected, with optical distortion less than ±0.3%.

[0143] Figure 16 This is a schematic diagram of the MTF curve of an industrial lens at the optimal object distance provided in Embodiment 3 of the present invention. The image quality of the lens of the present invention at 250pl / mm from the center field of view to the edge field of view is higher than 0.2 MTF, and the imaging has excellent resolution.

[0144] Figure 17 This is a schematic diagram of the axial chromatic aberration curve of an industrial lens at the optimal object distance, provided in Embodiment 3 of the present invention. In the figure, the vertical direction represents the normalized 0-field pupil plane, where 0 represents the pupil center, and the vertical vertex represents the pupil vertex. The horizontal direction represents the axial chromatic aberration at different wavelengths (specifically 460nm, 530nm, and 620nm), in millimeters (mm). As shown in the figure, the axial chromatic aberration of the entire pupil of the lens of the present invention is less than 25μm, resulting in excellent image sharpness.

[0145] Figure 18 This is a schematic diagram of the transverse chromatic aberration curve of an industrial lens at the optimal object distance, provided in Embodiment 3 of the present invention. In the figure, the vertical direction represents the field of view angle, 0 represents the field of view angle incident parallel to the optical axis, and the vertex of the vertical direction represents the maximum half field of view angle. As shown in the figure, at each wavelength of the system (specifically 460nm, 530nm, and 620nm), the transverse chromatic aberration from the center field of view to the edge field of view of the lens is less than 0.5μm, resulting in higher imaging quality.

[0146] In summary, the industrial lens provided in this embodiment of the invention adopts an all-glass 10G structure. Through the combination of lens materials and the reasonable allocation of the optical power of each component, an industrial lens design that can take into account wide object distance, high resolution, and low optical distortion is achieved. It can achieve focusing at an object distance of 100mm to infinity, with a focal length of 47.998mm, an image-side F number of 2.804, a target surface of Φ11.814mm, and optical distortion ≤0.3%.

[0147] The specific embodiments described above do not constitute a limitation on the scope of protection of this invention. Those skilled in the art should understand that various modifications, combinations, sub-combinations, and substitutions can be made according to design requirements and other factors. Any modifications, equivalent substitutions, and improvements made within the spirit and principles of this invention should be included within the scope of protection of this invention.

Claims

1. An industrial lens, characterized in that, It includes a focusing lens group, an aperture, and a fixed lens group arranged sequentially from the object plane to the image plane along the optical axis. The position of the focusing lens group can float along the optical axis, and the position of the fixed lens group is fixed. The focusing lens group includes a first lens, a second lens, a third lens, a fourth lens, a fifth lens, and a sixth lens arranged sequentially along the optical axis from the object plane to the image plane; The fixed lens group includes a seventh lens, an eighth lens, a ninth lens, and a tenth lens arranged sequentially along the optical axis from the object plane to the image plane; the industrial lens has ten lenses with optical power. The first lens is a positive power lens, the second lens is a positive power lens, the third lens is a positive power lens, the fourth lens is a negative power lens, the fifth lens is a positive power lens, the sixth lens is a negative power lens, the seventh lens is a negative power lens, the eighth lens is a negative power lens, the ninth lens is a positive power lens, and the tenth lens is a positive power lens. The focal length of the first lens is F1, the focal length of the second lens is F2, the focal length of the third lens is F3, the focal length of the fourth lens is F4, the focal length of the fifth lens is F5, the focal length of the sixth lens is F6, the focal length of the seventh lens is F7, the focal length of the eighth lens is F8, the focal length of the ninth lens is F9, the focal length of the tenth lens is F10, and the total focal length of the industrial lens is F. Among them, 1.921 <F1 / F<2.292,2.552 <F2 / F<3.431,1.010 <F3 / F<1.798,-1.165<F4 / F<-0.549,0.359 <F5 / F<0.494,-3.056 <F6 / F<-2.375,-0.868<F7 / F<-0.645,-0.466 <F8 / F<-0.389,0.761 <F9 / F<0.917,0.598<F10 / F<0.966。 2. The industrial lens according to claim 1, characterized in that, The third lens and the fourth lens are cemented together to form a first cemented lens group, and the fifth lens and the sixth lens are cemented together to form a second cemented lens group.

3. The industrial lens according to claim 2, characterized in that, The Abbe number of the third lens is VD3, the Abbe number of the fourth lens is VD4, the optical power of the third lens is Φ3, the optical power of the fourth lens is Φ4, and the optical power of the first cemented lens group is Φ3-4. Of which, 45,000 <VD3<58.873,38.803<VD4<40.001, -0.536≤1000*(Φ3 / VD3+Φ4 / VD4)≤-0.332, 10*|Φ3+Φ4-Φ3-4|<0.

034.

4. The industrial lens according to claim 2, characterized in that, The Abbe number of the fifth lens is VD5, the Abbe number of the sixth lens is VD6, the optical power of the fifth lens is Φ5, the optical power of the sixth lens is Φ6, and the optical power of the second cemented lens group is Φ5-6. Of which, 80,000 <VD5<92.968,14.997 <VD6<25.866, 0.052≤1000*(Φ5 / VD5+Φ6 / VD6)≤0.286, 10*|Φ5+Φ6-Φ5-6|<0.

104.

5. The industrial lens according to claim 1, characterized in that, The industrial lens has a back focal length of BFL, a total optical length of TTL, and a total focal length of F. Among them, 0.240 <BFL / F<0.254,0.522<F / TTL<0.552。 6. The industrial lens according to claim 1, characterized in that, The first lens includes a first object-side surface near the object plane and a first image-side surface near the image plane. The first object-side surface is convex, and the first image-side surface is concave. The second lens includes a second object-side surface near the object plane and a second image-side surface near the image plane, wherein the second object-side surface is convex and the second image-side surface is concave. The third lens includes a third object-side surface near the object plane and a third image-side surface near the image plane. The third object-side surface is convex, and the third image-side surface is concave. The fourth lens includes a fourth object-side surface near the object plane and a fourth image-side surface near the image plane. The fourth object-side surface is convex, and the fourth image-side surface is concave. The fifth lens includes a fifth object-side surface near the object plane and a fifth image-side surface near the image plane. The fifth object-side surface is convex, and the fifth image-side surface is convex. The sixth lens includes a sixth object-side surface near the object plane and a sixth image-side surface near the image plane. The sixth object-side surface is concave, and the sixth image-side surface is convex. The seventh lens includes a seventh object-side surface near the object plane and a seventh image-side surface near the image plane. The seventh object-side surface is convex, and the seventh image-side surface is concave. The eighth lens includes an eighth object-side surface near the object plane and an eighth image-side surface near the image plane. The eighth object-side surface is concave, and the eighth image-side surface is concave. The ninth lens includes a ninth object-side surface near the object plane and a ninth image-side surface near the image plane. The ninth object-side surface is concave, and the ninth image-side surface is convex. The tenth lens includes a tenth object-side surface near the object plane and a tenth image-side surface near the image plane. The tenth object-side surface is convex, and the tenth image-side surface is concave.

7. The industrial lens according to claim 1, characterized in that, The first lens through the tenth lens are all glass spherical lenses.

Images