An ultraviolet ultrafast laser telecentric lens group and a laser processing device

Abstract

The embodiment of the application discloses a kind of ultraviolet ultrafast laser telecentric lens group and laser processing equipment, ultraviolet ultrafast laser telecentric lens group includes the first lens, second lens, third lens, fourth lens and fifth lens sequentially arranged along the incident direction of light, first lens is bi-convex positive lens, second lens is bi-concave negative lens, third lens is meniscus negative lens, fourth lens is meniscus positive lens, fifth lens is bi-convex positive lens.The ultraviolet ultrafast laser telecentric lens group of the application makes that exit pupil is at infinite far place in image space, chief ray of focused light beam is perpendicular to focal plane in any full field angle, avoids punching inclination, while effectively corrects astigmatism and distortion of laser telecentric lens group, realizes image far telecentric optical path, improves image quality.In addition, the lens structure of the application is simple, easy to design, can be widely used in various fine laser processing equipment.

Description

TECHNICAL FIELD

[0001] The application relates to the technical field of optical lens groups and laser lens technology, in particular to an ultraviolet ultrafast laser telecentric lens group and an ultraviolet laser lens fine processing equipment. BACKGROUND

[0002] The shorter the wavelength of the laser, the finer the focused light spot can be obtained. In the field of industrial laser processing, the pulse frequency of pulsed laser is getting faster and faster, and 500 femtosecond pulse width ultraviolet laser has been widely used in ultra-fine processing field, especially in the application of display panel (mini-LED) industry. The 500Fs ultraviolet laser of 343nm waveband has been quite mature, and the power has been increasing, which makes many ultra-fine industrial processing possible.

[0003] At present, when using a non-ultraviolet ultrafast laser telecentric lens group to punch, there is a certain inclination angle between the image side chief ray and the focal plane, which causes the processed hole to have a certain inclination. In addition, when the processed object is defocused from the non-ultraviolet ultrafast laser telecentric lens group, additional distortion will be caused, which reduces the processing precision.

[0004] Therefore, when laser punching is performed, how to avoid punching inclination and correct the astigmatism and distortion of the laser telecentric lens group to realize the image side telecentric light path and improve the imaging quality becomes a technical problem to be solved. SUMMARY

[0005] The embodiment of the application provides an ultraviolet ultrafast laser telecentric lens group and a laser processing equipment to solve the technical problem that how to avoid punching inclination and correct the astigmatism and distortion of the laser telecentric lens group to realize the image side telecentric light path and improve the imaging quality when laser punching is performed.

[0006] In order to solve the above technical problem, the embodiment of the application provides an ultraviolet ultrafast laser telecentric lens group, which adopts the technical scheme as follows:

[0007] An ultraviolet ultrafast laser telecentric lens group, comprising a first lens, a second lens, a third lens, a fourth lens and a fifth lens arranged in sequence along the incident direction of light rays, the first lens is a biconvex positive lens, the second lens is a biconcave negative lens, the third lens is a meniscus negative lens, the fourth lens is a meniscus positive lens, and the fifth lens is a biconvex positive lens.

[0008] Further, the focal length of the ultraviolet ultrafast laser telecentric lens group is 500mm, the full field angle is 32°, the allowable tolerance of the ultraviolet ultrafast laser telecentric lens group is 10%, the upper deviation is +5%, and the lower deviation is -5%.

[0009] Further, the first lens comprises a first curved surface and a second curved surface, the second lens comprises a third curved surface and a fourth curved surface, the third lens comprises a fifth curved surface and a sixth curved surface, the fourth lens comprises a seventh curved surface and an eighth curved surface, and the fifth lens comprises a ninth curved surface and a tenth curved surface, wherein the first curved surface to the tenth curved surface are arranged in sequence along the direction of the incident light, the radii of curvature of the first curved surface to the tenth curved surface are 148.5 mm, -265 mm, -171.5 mm, 133.5 mm, -104 mm, -170.5 mm, -1395 mm, -258 mm, 947.5 mm, and -345.5 mm, respectively, the allowable tolerance of the radii of curvature is 10%, the upper deviation is +5%, and the lower deviation is -5%.

[0010] Further, the distance between the second curved surface and the third curved surface on the optical axis is 16 mm, the distance between the fourth curved surface and the fifth curved surface on the optical axis is 94 mm, the distance between the sixth curved surface and the seventh curved surface on the optical axis is 18 mm, and the distance between the eighth curved surface and the ninth curved surface on the optical axis is 1 mm, respectively, the allowable tolerance of the distance is 10%, the upper deviation is +5%, and the lower deviation is -5%.

[0011] Further, the center thicknesses of the first lens to the fifth lens on the optical axis are 87 mm, 9 mm, 50 mm, 33.5 mm, and 46 mm, respectively, the allowable tolerance of the center thicknesses is 10%, the upper deviation is +5%, and the lower deviation is -5%.

[0012] Further, the ratios of the refractive index to the Abbe number of the first lens, the second lens, the third lens, the fourth lens, and the fifth lens are all 1.4585 / 67.82, the allowable tolerance of the ratio of the refractive index to the Abbe number is 10%, the upper deviation is +5%, and the lower deviation is -5%.

[0013] Further, the entrance pupil diameter of the ultraviolet ultrafast laser telecentric lens group is 20 mm.

[0014] Further, the telecentricity of the ultraviolet ultrafast laser telecentric lens group is less than 3.2°.

[0015] Further, the wavelength of the incident light beam of the ultraviolet ultrafast laser telecentric lens group is 343 nm, and the pulse width is 500 fs.

[0016] To solve the above technical problems, the embodiment of the present application also provides a laser processing equipment, which adopts the technical scheme as follows:

[0017] A laser processing equipment, the laser processing equipment comprising the ultraviolet ultrafast laser telecentric lens group as described above.

[0018] Compared with the prior art, the embodiment of the present application has the following beneficial effects:

[0019] The embodiment of the present application discloses a kind of ultraviolet ultrafast laser telecentric lens group and laser processing equipment, ultraviolet ultrafast laser telecentric lens group includes the first lens, second lens, third lens, fourth lens and fifth lens in turn arranged along the incident direction of light, first lens is bi-convex positive lens, second lens is bi-concave negative lens, third lens is meniscus negative lens, fourth lens is meniscus positive lens, and fifth lens is bi-convex positive lens.The ultraviolet ultrafast laser telecentric lens group of the present application makes that exit pupil is at infinite distance in image space, chief ray of focused light beam is perpendicular to focal plane in any full field angle, avoids punching inclination, while effectively corrects astigmatism and distortion of laser telecentric lens group, realizes image telecentric optical path, improves image quality.In addition, the lens structure of the present application is simple, easy to design, can be widely applied in various fine laser processing equipment. BRIEF DESCRIPTION OF DRAWINGS

[0020] In order to more clearly illustrate the scheme in the present application or prior art, the following will be a brief introduction to the drawings needed to be used in the embodiment or prior art description, obviously, the drawings in the following description are some embodiments of the present application, and those skilled in the art can also obtain other drawings according to these drawings without creating labor.

[0021] Figure 1 It is a structure schematic diagram of ultraviolet ultrafast laser telecentric lens group in an embodiment;

[0022] Figure 2 It is a geometric aberration curve diagram of ultraviolet ultrafast laser telecentric lens group in an embodiment;

[0023] Figure 3 It is a distortion curve diagram of ultraviolet ultrafast laser telecentric lens group in an embodiment;

[0024] Figure 4 It is an optical transfer function O.T.F curve diagram of ultraviolet ultrafast laser telecentric lens group in an embodiment;

[0025] Figure 5 It is an M.T.F curve diagram of transfer function of ultraviolet ultrafast laser telecentric lens group in an embodiment;

[0026] Figure 6 It is a diffraction spot diagram of ultraviolet ultrafast laser telecentric lens group in an embodiment;

[0027] Figure 7 It is an energy concentration degree diagram of ultraviolet ultrafast laser telecentric lens group in an embodiment. DETAILED DESCRIPTION

[0028] Unless otherwise defined, all technical and scientific terms used herein have the same meaning as commonly understood by one of ordinary skill in the art to which this application belongs; the terminology used in the description herein is for describing particular embodiments only and is not intended to be limiting of the application; the description herein and the claims of the application and the appended drawings are to be interpreted strictly, the terms "comprising," "including," "incorporating," "having," "containing," and variations thereof in the detailed description, specifications, and claims are inclusive, the terms "first," "second," and the like in the description and the claims of this application are used for distinguishing between similar elements and not necessarily for describing a particular sequential or chronological order. It is to be understood that the terms so used are interchangeable under appropriate circumstances such that the embodiments of the application described herein are capable of operation in other sequences than described or otherwise illustrated herein.

[0029] Reference herein to "an embodiment" means that a particular feature, structure, or characteristic described in connection with the embodiment can be included in at least one embodiment of the application. The appearances of the phrase in various places in the specification are not necessarily all referring to the same embodiment, nor are they necessarily mutually exclusive of one another. It is expressly understood that the embodiments described herein are merely examples from a multitude of embodiments that are in compliance with the principles of the application.

[0030] For the purposes of the present application, the term "about" means plus or minus 10% of the specified value.

[0031] It is to be understood that the singular forms "a," "an," and "the" include plural referents unless the context clearly dictates otherwise. It is to be understood that the term "comprising" means "including, but not limited to."

[0032] It is to be understood that the terms "above" and "below" are used in relation to the direction of light propagation, and the terms "upper" and "lower" are used in relation to the orientation of the lens.

[0033] At present, when using non-ultraviolet ultrafast laser telecentric lens group to drill, there is a certain angle between the chief ray on the image side and the focal plane, which causes the drilled hole to have a certain slope. In addition, when the object to be processed has a certain defocus from the non-ultraviolet ultrafast laser telecentric lens group, additional distortion will be caused, reducing the processing precision.

[0034] And the ultraviolet ultrafast laser telecentric lens group in the F-Theta lens refers to the image side telecentric light path, and the convergence center of the image side chief ray parallel to the optical axis chief ray is located at the image side infinity. Compared with the ordinary laser F-Theta lens, more accurate wide-angle end precision can be obtained, the overall distortion of the working surface is smaller, and a relatively uniform focused spot diameter can be obtained in the entire scanning range, which is a very important target in ultra-fine machining.

[0035] Based on this, the embodiment of the application discloses an ultraviolet ultrafast laser telecentric lens group and a laser processing equipment to solve the above technical problems. As shown in the figure Figure 1 The ultraviolet ultrafast laser telecentric lens group 100 includes a first lens 10, a second lens 20, a third lens 30, a fourth lens 40 and a fifth lens 50 arranged in sequence along the incident direction of the light, the first lens 10 is a double-convex positive lens, the second lens 20 is a double-concave negative lens, the third lens 30 is a meniscus negative lens, the fourth lens 40 is a meniscus positive lens, and the fifth lens 50 is a double-convex positive lens. The focal length of the ultraviolet ultrafast laser telecentric lens group 100 is 500 mm, the allowable tolerance is 10%, the upper deviation is +5%, the lower deviation is -5%, and the full field of view angle is 32°.

[0036] In order to obtain a more fine processing area, it is necessary to reduce the scanning field of view range of the ultraviolet ultrafast laser telecentric lens group 100 as much as possible. The focal length of the ultraviolet ultrafast laser telecentric lens group 100 is designed to be 500 mm, and the full field of view angle is 32°. Without moving the processing object or the workbench, the scanning field of view range of the ultraviolet ultrafast laser telecentric lens group 100 of the application is 200 mm*200 mm, and the ultra-fine machining precision can be obtained.

[0037] In the specific embodiment of the application, the ultraviolet ultrafast laser telecentric lens group 100 of the application is specially designed, so that the exit pupil is at the image space infinity, the chief ray of the focused light beam is perpendicular to the focal plane in any full field of view angle, the punching inclination can be avoided, the distortion caused by the slight defocus of the processing object is reduced, and the purpose of ultra-fine machining is achieved.

[0038] The ultraviolet ultrafast laser telecentric lens group 100 of the application is designed by the shape and relative position of the first lens 10, the second lens 20, the third lens 30, the fourth lens 40 and the fifth lens 50, which effectively corrects the astigmatism and distortion, realizes the image side telecentric light path, improves the imaging quality. At the same time, the laser energy concentration degree is high, the lens structure is simple, it is convenient to design, and it can be widely applied to various fine laser processing equipment.

[0039] The wavelength λ of the incident laser beam of the ultraviolet ultrafast laser telecentric lens group 100 is 343 nm.

[0040] In the specific embodiment of the present application, the spot diameter after focusing is calculated according to the theoretical calculation formula of the focused diffused spot:

[0041] spotΦ=1.83*λ*EFL / beamΦ

[0042] In the formula, spotΦ is the spot diameter after focusing (i.e. the size of the focused diffused spot);

[0043] λ is the wavelength of the processing laser beam;

[0044] EFL is the focal length of the ultraviolet ultrafast laser telecentric lens group 100;

[0045] beamΦ is the entrance pupil diameter of the ultraviolet ultrafast laser telecentric lens group 100.

[0046] As can be seen from the above formula, a focused spot diameter of 15 μm can be obtained, and a more precise cutting line width can be obtained by using an ultrashort wavelength laser beam. The wavelength λ of the ultraviolet laser used in the present embodiment is 343 nm, and theoretically its resolution is three times greater than that of a 1064 nm wavelength laser. Since the materials of the first lens 10, the second lens 20, the third lens 30, the fourth lens 40 and the fifth lens 50 of the ultraviolet ultrafast laser telecentric lens group 100 are all fused quartz, the ultraviolet ultrafast laser telecentric lens group 100 can be applied to a ultraviolet wavelength laser λ = 343 nm, and a very high resolution point distance can be obtained, i.e. an ultra-fine focused diffused spot can be obtained. Due to the characteristics of fused quartz, the ultraviolet ultrafast laser telecentric lens group 100 is suitable for high power density, i.e. it can be applied to a 20 w picosecond ultraviolet laser.

[0047] The entrance pupil diameter beamΦ of the ultraviolet ultrafast laser telecentric lens group 100 is 20 mm, which ensures the light quantity per unit time and at the same time makes the ultraviolet ultrafast laser telecentric lens group 100 obtain a relatively small volume.

[0048] In the specific embodiment of the present application, the first lens 10 is composed of a first curved surface 11 and a second curved surface 12, the second lens 20 is composed of a third curved surface 21 and a fourth curved surface 22, the third lens 30 is composed of a fifth curved surface 31 and a sixth curved surface 32, the fourth lens 40 is composed of a seventh curved surface 41 and an eighth curved surface 42, and the fifth lens 50 is composed of a ninth curved surface 51 and a tenth curved surface 52, wherein the first curved surface 11 to the tenth curved surface 52 are arranged in sequence along the direction of the incident light, the radius of curvature of the first curved surface 11 is 148.5±5%mm, the radius of curvature of the second curved surface 12 is -265±5%mm, the radius of curvature of the third curved surface 21 is -171.5±5%mm, the radius of curvature of the fourth curved surface 22 is 133.5±5%mm, the radius of curvature of the fifth curved surface 31 is -104±5%mm, the radius of curvature of the sixth curved surface 32 is -170.5±5%mm, the radius of curvature of the seventh curved surface 41 is -1395±5%mm, the radius of curvature of the eighth curved surface 42 is -258±5%mm, the radius of curvature of the ninth curved surface 51 is 947.5±5%mm, and the radius of curvature of the tenth curved surface 52 is -345.5±5%mm.

[0049] In the specific embodiment of the present application, the central thickness d1 of the first lens 10 on the optical axis is 87±5%mm, the central thickness d2 of the second lens 20 on the optical axis is 9±5%mm, the central thickness d3 of the third lens 30 on the optical axis is 50±5%mm, the central thickness d4 of the fourth lens 40 on the optical axis is 33.5±5%mm, and the central thickness d5 of the fifth lens 50 on the optical axis is 46±5%mm.

[0050] In the specific embodiment of the present application, the interval S1 of the second curved surface 12 and the third curved surface 21 on the optical axis is 16±5%mm, the interval S2 of the fourth curved surface 22 and the fifth curved surface 31 on the optical axis is 94±5%mm, the interval S3 of the sixth curved surface 32 and the seventh curved surface 41 on the optical axis is 18±5%mm, and the interval S4 of the eighth curved surface 42 and the ninth curved surface 51 on the optical axis is 1±5%mm.

[0051] In the specific embodiment of the present application, the ratio of the refractive index to the Abbe number of the first lens 10 is 1.4585 / 67.82±5%, the ratio of the refractive index to the Abbe number of the second lens 20 is 1.4585 / 67.82±5%, the ratio of the refractive index to the Abbe number of the third lens 30 is 1.4585 / 67.82±5%, the ratio of the refractive index to the Abbe number of the fourth lens 40 is 1.4585 / 67.82±5%, and the ratio of the refractive index to the Abbe number of the fifth lens 50 is 1.4585 / 67.82±5%.

[0052] In one specific embodiment of the present application, the structure parameters of the ultraviolet superfast laser telecentric lens group 100 are shown in the following table:

[0053] Table 1 Structure parameters of the ultraviolet ultrafast laser telecentric lens group 100

[0054]

[0055] From Figure 2 And Figure 3 It can be seen that the ultraviolet ultrafast laser telecentric lens group 100 is precisely corrected, which effectively alleviates the field curvature and distortion problems, and further improves the imaging quality in the entire scanning range. The image plane is flat, the astigmatism is small, and it ensures that the imaging is very accurate whether in the center of the optical axis or in the edge area. This high-precision imaging capability makes the lens group particularly suitable for fields that require ultra-fine and high-precision processing, especially in high-demand application scenarios such as ultraviolet ultrafast laser processing.

[0056] Through optimization, the field curvature and distortion problems of the ultraviolet ultrafast laser telecentric lens group are effectively solved. Field curvature refers to the difference in curvature of the image plane at different positions, which usually causes distortion of the image in the edge area. Distortion refers to the deformation of the image geometry, such as stretching or compression. After correction, the flat image plane means that the focal plane of the image has been optimized, reducing distortion or distortion, and the clarity and accuracy of the image have been significantly improved.

[0057] Moreover, the performance of the lens group is uniform throughout the scanning range, whether it is axial (center of the optical axis) or off-axis (areas away from the optical axis), the image quality remains consistent and there is no obvious aberration or distortion. This indicates that the lens group has very stable imaging effects at various positions, suitable for high-precision optical applications.

[0058] Astigmatism refers to the asymmetry of imaging caused by imperfect lenses or improper design, usually manifested as stretching or compression of the image in certain directions. After using the ultraviolet ultrafast laser telecentric lens group 100, the astigmatism is small, that is, the lens group has less point spread during imaging, thereby improving the resolution. Smaller astigmatism means that the system can provide higher accuracy in ultra-fine and high-precision processing, especially in the fields of laser processing, micro-processing, etc., to obtain more accurate workpiece surface quality.

[0059] From Figure 4 And Figure 5respectively represent the performance of the optical transfer function (O.T.F) and modulation transfer function (M.T.F) of the ultraviolet superfast laser telecentric lens group 100 for ultraviolet laser. O.T.F is a function that describes the transfer ability of an optical system in the spatial frequency domain for different spatial frequency components, reflecting the overall imaging quality of the system. O.T.F can characterize the response of the system under different conditions, especially the transfer ability of different frequencies (details). M.T.F is a specific representation of contrast transfer function, indicating the ability of the system to transfer image contrast. It is usually used to measure the resolution ability of the system at different spatial frequencies, reflecting the sharpness and resolution in imaging. These two functions are important tools for evaluating the imaging performance of an optical system, which can quantify how the system transfers different spatial frequency optical information, thereby helping to analyze the imaging quality.

[0060] By Figure 4 and Figure 5 It can also be seen that there is no significant difference between the on-axis point and the off-axis point of the ultraviolet superfast laser telecentric lens group 100 for ultraviolet laser, that is, whether in the center of the optical axis or in the area deviating from the optical axis, the sharpness, contrast and resolution of the image remain consistent, achieving the purpose of flat field. Flat field means that the focal plane of the imaging system is flat within the entire field of view, and the image quality remains consistent at each position without significant distortion or aberration. Through the analysis of O.T.F and M.T.F, it is shown that the lens group has reached this ideal state, and can provide consistent imaging effect within the entire scanning or observation range, especially in the on-axis and off-axis areas.

[0061] Figure 6 and Figure 7 The diffraction spot and energy concentration degree after using the ultraviolet superfast laser telecentric lens group 100 for ultraviolet laser are shown. The size of the diffraction spot is controlled at about 15 μm in all fields of view, and all the energy is concentrated in about 15 μm. It can be seen that after using the ultraviolet superfast laser telecentric lens group 100, the laser energy concentration degree is extremely high, so that accurate marking or cutting can be achieved.

[0062] The diffraction spot is the spot shape at the focal point after the laser is focused through the lens. The size and shape of the diffraction spot reflect the focusing quality of the laser. A small range and regular shape of the spot indicate good focusing effect of the laser, which is suitable for high-precision machining.

[0063] Energy concentration degree refers to the concentration of laser beam energy in the focusing area. High concentration degree means that most of the laser energy is concentrated in a small range, thereby improving the machining precision and efficiency.

[0064] After using the ultraviolet ultrafast laser telecentric lens group 100, the size of the diffraction spot remains consistent in different field of view ranges, and is controlled at about 15 μm, indicating that the lens group has good optical quality and can maintain stable focusing effect in different working ranges. The size of the diffraction spot is 15 μm, indicating that the laser beam spot at the focusing point is very small and the precision is very high, which is suitable for micro machining. The cutting energy is concentrated in an area of about 15 μm, and the laser energy is almost completely concentrated in a very small area. This high energy concentration is crucial for fine machining (such as laser cutting, marking, etc.), which can produce high temperature in a small range, thereby effectively processing materials.

[0065] In summary, the ultraviolet ultrafast laser telecentric lens group 100 improves the focusing precision and energy concentration of the laser, ensuring the stability and efficiency of the laser in different field of view ranges, and is particularly suitable for laser processing applications that require high precision and high energy density.

[0066] In another specific embodiment of the present application, the present application also discloses a laser processing equipment, specifically an ultraviolet laser fine machining equipment, which comprises an ultraviolet laser and an ultraviolet ultrafast laser telecentric lens group 100 for focusing the ultraviolet laser. The laser processing equipment can be a laser drilling machine, a laser marking machine or a laser cutting machine.

[0067] The ultraviolet laser has an emission wavelength of 343 nm, and the power of the ultraviolet laser is equal to or greater than 20 W. The laser processing equipment further comprises a beam expander, an X galvanometer and a Y galvanometer. The laser emitted by the ultraviolet laser passes through the beam expander, the X galvanometer and the Y galvanometer in sequence, and is finally focused on the image plane by the ultraviolet ultrafast laser telecentric lens group 100. The scanning field of view range of the ultraviolet ultrafast laser telecentric lens group 100 reaches 200 mm*200 mm, which can meet the demand for ultra-fine machining area and effectively improve the production efficiency. Further, the chief ray of the ultraviolet ultrafast laser telecentric lens group 100 to each field of view direction is perpendicular to the image plane, thereby avoiding drilling inclination, and at the same time, avoiding distortion caused by slight defocusing of the processed object, thereby ensuring the machining precision. At the same time, due to the small astigmatism of the ultraviolet ultrafast laser telecentric lens group 100, the dramatic change of the machining shape caused by slight defocusing or tilting of the processed object can be avoided.

[0068] The technical features of the above-described embodiments can be combined in any way. To make the description concise, not all possible combinations of the technical features in the above-described embodiments are described, but as long as the combinations of the technical features do not contradict, they should be considered within the scope of the present disclosure.

[0069] The above described embodiments only express several embodiments of the present application, which are described in a more specific and detailed manner, but should not be understood as limiting the scope of the patent. It should be noted that for those skilled in the art, several modifications and improvements can be made without departing from the concept of the present application, which are all within the scope of protection of the present application. Therefore, the scope of protection of the patent of the present application should be subject to the appended claims.

[0070] Obviously, the above described embodiments are only part of the embodiments of the present application, rather than all the embodiments, and the preferred embodiments of the present application are given in the drawings, but do not limit the patent scope of the present application. The present application can be implemented in many different forms, and conversely, the purpose of providing these embodiments is to make the disclosure of the present application more thorough and comprehensive. Although the present application has been described in detail with reference to the foregoing embodiments, those skilled in the art can still modify the technical solutions recorded in the foregoing specific embodiments, or make equivalent replacements for part of the technical features. Any equivalent structure made by using the content of the specification and drawings, directly or indirectly applied to other related technical fields, is also within the scope of protection of the present application.

Claims

1. A telecentric lens assembly for ultraviolet ultrafast laser, characterized in that, The lens with optical power consists of 5 elements, including a first lens, a second lens, a third lens, a fourth lens, and a fifth lens arranged sequentially along the incident direction of the light. The first lens is a biconvex positive lens, the second lens is a biconcave negative lens, the third lens is a meniscus negative lens, the fourth lens is a meniscus positive lens, and the fifth lens is a biconvex positive lens. The first lens includes a first curved surface and a second curved surface; the second lens includes a third curved surface and a fourth curved surface; the third lens includes a fifth curved surface and a sixth curved surface; the fourth lens includes a seventh curved surface and an eighth curved surface; and the fifth lens includes a ninth curved surface and a tenth curved surface. The first to tenth curved surfaces are arranged sequentially along the direction of the incident light ray. The radii of curvature of the first to tenth curved surfaces are 148.5 mm, -265 mm, -171.5 mm, 133.5 mm, -104 mm, -170.5 mm, -1395 mm, -258 mm, 947.5 mm, and -345.5 mm, respectively. The allowable tolerance for the radii of curvature is 10%, with an upper deviation of +5% and a lower deviation of -5%. The distance between the second and third curved surfaces on the optical axis is 16 mm, the distance between the fourth and fifth curved surfaces on the optical axis is 94 mm, the distance between the sixth and seventh curved surfaces on the optical axis is 18 mm, and the distance between the eighth and ninth curved surfaces on the optical axis is 1 mm. The allowable tolerance for the distance is 10%, with an upper deviation of +5% and a lower deviation of -5%. The center thicknesses of the first lens to the fifth lens on the optical axis are 87mm, 9mm, 50mm, 33.5mm, and 46mm, respectively. The allowable tolerance for the center thickness is 10%, with an upper deviation of +5% and a lower deviation of -5%. The refractive index to Abbe number ratio of the first lens, the second lens, the third lens, the fourth lens, and the fifth lens is 1.4585 / 67.

82. The allowable tolerance for the refractive index to Abbe number ratio is 10%, with an upper deviation of +5% and a lower deviation of -5%.

2. The ultraviolet ultrafast laser telecentric lens assembly according to claim 1, characterized in that, The focal length of the ultraviolet ultrafast laser telecentric lens group is 500mm, the full field of view is 32°, and the allowable tolerance of the ultraviolet ultrafast laser telecentric lens group is 10%, with an upper deviation of +5% and a lower deviation of -5%.

3. The ultraviolet ultrafast laser telecentric lens assembly according to claim 1, characterized in that, The entrance pupil diameter of the ultraviolet ultrafast laser telecentric lens group is 20 mm.

4. The ultraviolet ultrafast laser telecentric lens group according to claim 1, characterized in that, The telecentricity of the ultraviolet ultrafast laser telecentric lens group is less than 3.2°.

5. The ultraviolet ultrafast laser telecentric lens group according to claim 1, characterized in that, The incident beam wavelength of the ultraviolet ultrafast laser telecentric lens group is 343nm, and the pulse width is 500fs.

6. A laser processing device, characterized in that, The laser processing equipment includes the ultraviolet ultrafast laser telecentric lens group as described in any one of claims 1-5.

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