Optical system for laser cutting, laser processing device and method

Abstract

Embodiments of the present application provide an optical system for laser cutting, a laser processing device and a method. The optical system comprises, in sequence along an optical path direction, a laser, a beam processing element, a spherical aberration compensation assembly and an objective lens, wherein the laser is configured to emit a laser beam; the beam processing element is configured to process the laser beam to obtain a predetermined number of sub-beams; the spherical aberration compensation assembly comprises a predetermined number of sub-spherical aberration compensation elements, the predetermined number of sub-spherical aberration compensation elements correspond to the predetermined number of sub-beams one by one, and each sub-spherical aberration compensation element is configured to compensate the spherical aberration of the sub-beam passing through the corresponding sub-spherical aberration compensation element; and the sub-beams compensated by the sub-spherical aberration compensation elements are focused by the objective lens to form a burst point at a predetermined position of the processed object. The technical solution can obtain a better cutting effect with fewer cutting times or cutting layers, thereby effectively improving the efficiency of laser cutting.

Description

TECHNICAL FIELD

[0001] The present application relates to the technical field of semiconductor processing, and more particularly to an optical system for laser cutting, a laser processing device and a laser processing method. BACKGROUND

[0002] With China continuously promoting the adjustment of industrial structure and energy structure, vigorously developing renewable energy, the new energy industry has strong demand for semiconductor devices based on the application of third-generation semiconductor materials (SiC, GaN, etc.), which promotes the chip industry to layout third-generation semiconductor devices, and at the same time, puts forward new challenges to the cutting and separation process of semiconductor devices. The traditional cutter wheel cutting method is limited in production efficiency and increases the cutting cost (one cutter is needed to cut one SiC wafer) due to the hardness of the material (such as SiC Mohs hardness 9.5, close to diamond hardness), and there are problems such as strict appearance edge collapse requirement and potential crack risk after cutting, which makes the traditional cutter wheel cutting method have no economic advantage, so using laser cutting becomes the optimal solution.

[0003] And the traditional laser cutting mainly uses laser stealth cutting technology, which mainly focuses the laser beam inside the processed object to form a modified layer (explosion point connection area), controls the distance between points accurately to form micro-cracks inside, and then uses a splitting knife or vacuum splitting to separate the adjacent crystal grains from each other.

[0004] However, for wafers with a thickness greater than 100 μm (including 100 μm) or more, K (K≥2) modified layers need to be formed at different depth positions of a cutting path of the wafer. Due to the refraction of laser into the material, each laser focused inside the material will produce spherical aberration. The generation of spherical aberration will affect the quality of laser explosion point, so that the cutting frequency needs to be increased to make the cracks connectable up and down for subsequent splitting, but this will affect the cutting efficiency. This cutting method is low in efficiency and cannot meet the cutting demand of the rapid development of the semiconductor industry.

[0005] Therefore, it is necessary to provide a high-efficiency laser cutting method. SUMMARY

[0006] The present application is proposed in consideration of the above problems. The present application provides an optical system for laser cutting, a laser processing device and a laser processing method.

[0007] According to an aspect of the present application, an optical system for laser cutting is provided, comprising a laser, a beam processing element, a spherical aberration compensation assembly and an objective lens arranged in sequence along an optical path direction, wherein the laser is configured to emit a laser beam; the beam processing element is configured to process the laser beam to obtain a predetermined number of sub-beams; the spherical aberration compensation assembly comprises a predetermined number of sub-spherical aberration compensation elements, the predetermined number of sub-spherical aberration compensation elements correspond to the predetermined number of sub-beams one by one, and each sub-spherical aberration compensation element is configured to compensate the spherical aberration of the sub-beam passing through the corresponding sub-spherical aberration compensation element; and the sub-beams compensated by the sub-spherical aberration compensation elements are focused by the objective lens to form a focal point at a predetermined position of a workpiece.

[0008] Exemplarily, the optical system for laser cutting further comprises a first beam angle adjustment assembly arranged along the optical path direction, the first beam angle adjustment assembly is located between the spherical aberration compensation assembly and the beam processing element, the first beam angle adjustment assembly comprises a predetermined number of sub-adjustment units, the predetermined number of sub-adjustment units correspond to the predetermined number of sub-beams one by one, and each sub-adjustment unit is configured to adjust the transmission angle of the corresponding sub-beam.

[0009] Exemplarily, each sub-adjustment unit in the first beam angle adjustment assembly is a mirror, and the transmission angle of the sub-beam corresponding to any mirror is adjusted by adjusting the angle of the mirror.

[0010] Exemplarily, the sub-beams reflected by each mirror in the first beam angle adjustment assembly are parallel.

[0011] Exemplarily, the optical system for laser cutting further comprises a first beam shaping assembly arranged along the optical path direction, the first beam shaping assembly is located between the spherical aberration compensation assembly and the beam processing element, the first beam shaping assembly comprises a predetermined number of sub-beam shaping elements, the predetermined number of sub-beam shaping elements correspond to the predetermined number of sub-beams one by one, and each sub-beam shaping element is configured to shape the corresponding sub-beam.

[0012] Exemplarily, each sub-beam shaping element in the first beam shaping assembly is an expander, the expander meets the wavelength and energy density requirements of the laser, and the expansion ratio of the expander is within the range of [1 times, 8 times].

[0013] Exemplarily, the beam processing element is specifically configured to adjust the laser beam into the predetermined number of sub-beams and emit the corresponding sub-beams one by one at a preset interval time.

[0014] Exemplarily, the beam processing element is an acousto-optic deflector, the variable deflection angle of the acousto-optic deflector is greater than or equal to 1 mrad, and the modulation frequency of the acousto-optic deflector is within the range of [10 MHz, 500 MHz].

[0015] Exemplarily, the optical system for laser cutting further comprises a first controller communicatively connected with the acousto-optic deflector, configured to control the deflection angle θ of the laser beam by controlling the modulation frequency f of the acousto-optic deflector, so as to obtain a sub-beam corresponding to the angle θ.

[0016] Exemplarily, the optical system for laser cutting further comprises a second beam shaping component arranged between the laser and the beam processing element, configured to adjust the optical parameters of the laser beam emitted from the laser, so that the adjusted optical parameters of the laser beam can meet the incidence requirements of the incident light of the beam processing element.

[0017] Exemplarily, each of the sub-spherical aberration compensation elements in the spherical aberration compensation component is a single lens or a combined lens group, and each lens of each of the sub-spherical aberration compensation elements is a spherical lens or an aspherical lens.

[0018] Exemplarily, the optical system for laser cutting further comprises a second beam angle adjusting component arranged between the spherical aberration compensation component and the objective lens, configured to converge all the compensated sub-beams output by the spherical aberration compensation component onto the objective lens.

[0019] Exemplarily, the second beam angle adjusting component comprises a first reflecting mirror arranged on the exit light path of a sub-spherical aberration compensation element at the outermost side of the predetermined number of sub-spherical aberration compensation elements and configured to reflect the corresponding sub-beam, and at least one beam combining lens arranged one by one on the exit light paths of the remaining sub-spherical aberration compensation elements and configured to reflect the sub-beam emitted from the corresponding sub-spherical aberration compensation element, wherein the first beam combining lens adjacent to the first reflecting mirror is further configured to allow the light beam reflected by the first reflecting mirror to pass through, each of the remaining beam combining lenses is further configured to allow the light beam emitted from the previous beam combining lens to pass through, and any beam combining lens is configured to combine the transmitted light passing through the beam combining lens and the reflected light reflected by the beam combining lens onto the same light path.

[0020] Exemplarily, the second beam angle adjusting component further comprises a second reflecting mirror, the first reflecting mirror is fixed, and the light propagating along the exit light path of the first reflecting mirror is incident perpendicularly into the objective lens after being reflected by the second reflecting mirror, and the optical system for laser cutting further comprises a second controller and at least one pneumatic guide rail, the at least one beam combining lens is arranged one by one on the at least one pneumatic guide rail, the second controller is communicatively connected with the at least one pneumatic guide rail, and is configured to adjust the exit light path of the corresponding beam combining lens to coincide with the exit light path of the first reflecting mirror by controlling the movement and / or rotation of any pneumatic guide rail.

[0021] According to another aspect of the present application, a laser processing device is provided, comprising a stage and the above-mentioned optical system for laser cutting, wherein the stage is configured to carry the object to be processed.

[0022] According to another aspect of the present application, a laser beam is emitted to the workpiece by the optical system for laser cutting described above to form a burst at a predetermined position of the workpiece.

[0023] The optical system for laser cutting and the laser processing device according to the embodiments of the present application can adjust the light beam incident to the objective lens by the spherical aberration compensation assembly to compensate the spherical aberration, thereby improving the stability of the modified layer, so that the cutting times or the cutting layers can be reduced when cutting thicker materials, and a better cutting effect can be obtained by using less cutting times or cutting layers, and thus the efficiency of the laser cutting can be effectively improved. BRIEF DESCRIPTION OF DRAWINGS

[0024] The above and other objects, features and advantages of the present application will become more apparent from the following detailed description when taken in conjunction with the accompanying drawings in which like reference characters refer to like parts throughout the figures. The drawings provided are for illustrative purposes only and, therefore, should not be considered to be limiting of the present application. In the drawings:

[0025] Figure 1 a schematic block diagram of an optical system for laser cutting according to an embodiment of the present application is shown;

[0026] Figure 2 a schematic diagram of the focusing of a light beam when there is no spherical aberration compensation assembly according to an embodiment of the present application is shown; and

[0027] Figure 3 a schematic diagram of the focusing of a light beam when there is a spherical aberration compensation assembly according to an embodiment of the present application is shown. DETAILED DESCRIPTION

[0028] In order to make the objects, technical solutions and advantages of the present application more apparent, the following will describe the example embodiments according to the present application in detail with reference to the drawings. Obviously, the described embodiments are only some of the embodiments of the present application, but not all the embodiments of the present application, and it should be understood that the present application is not limited to the example embodiments described herein. Based on the embodiments of the present application described in the present application, all other embodiments obtained by those skilled in the art without creative effort should fall within the protection scope of the present application.

[0029] In order to at least partially solve the above problems, according to the embodiments of the present application, an optical system for laser cutting is provided.

[0030] Figure 1 a schematic block diagram of an optical system for laser cutting 1000 according to an embodiment of the present application is shown. As shown in the figure, Figure 1As shown, the optical system 1000 for laser cutting can include, in sequence along the optical path direction, a laser 1100, a beam processing element 1200, a spherical aberration compensation assembly 1300, and an objective lens 1400. It is to be noted that Figure 1 The structure of the optical system 1000 for laser cutting shown and the arrangement of the elements therein are merely examples and not limitations of the present application, and the optical system for laser cutting according to the embodiments of the present application is not limited to Figure 1 the specific form shown. For example, Figure 1 The first beam angle adjustment assembly 1500, the first beam shaping assembly 1600, the second beam shaping assembly 1700, and the second beam angle adjustment assembly 1800 are shown as optional. For example, the laser 1100 can be arranged to emit a laser beam directly into the beam processing element 1200 by suitable arrangement and parameter setting of the elements, so that the second beam shaping assembly 1700 can not be needed. For another example, Figure 1 The second beam angle adjustment assembly 1800 is shown as including two mirrors and at least one beam combining lens, but the type and arrangement of the lenses included in the second beam angle adjustment assembly 1800 can be changed.

[0031] The laser 1100 is configured to emit a laser beam.

[0032] Optionally, the laser 1100 is selected to have a wavelength band that can be transmitted into the interior of the material of the workpiece. For example, the laser 1100 can be a picosecond laser. For example, a pulsed laser having a wavelength that can be transmitted into the interior of the material can be selected. For example, the laser 1100 can be selected to have a wavelength in the range of 266 nm to 1550 nm and a pulse width in the range of 1 ps to 500 ns.

[0033] The beam processing element 1200 is configured to process the laser beam to obtain a predetermined number of sub-beams.

[0034] In one embodiment, the predetermined number N≥1. Preferably, N≥2. The laser 1100 can be processed by the beam processing element 1200 into one or more sub-beams. In the case of multiple sub-beams, the power of any two sub-beams can be the same or different. The beam processing element 1200 can be implemented by any existing or future laser beam splitter to split the laser beam into one or more sub-beams. The beam processing element 1200 can also be implemented by any existing or future light deflector to obtain multiple sub-beams at different deflection angles at different times.

[0035] The spherical aberration compensation assembly 1300 includes a predetermined number of sub-spherical aberration compensation elements, each corresponding to a predetermined number of sub-beams. Each sub-spherical aberration compensation element is used to compensate for the spherical aberration of the sub-beam that has passed through the corresponding sub-spherical aberration compensation element. The sub-beam after compensation by the sub-spherical aberration compensation element is focused by the objective lens 1400 to form a blast point at a predetermined position on the workpiece.

[0036] For example, objective lens 1400 may be a compound lens group objective lens. Furthermore, for example, the magnification of objective lens 1400 is ≥10. In one example, any two different sub-beams, after being focused by objective lens 1400, can form explosion points at different depths of the workpiece. In another example, any two different sub-beams, after being focused by objective lens 1400, can form explosion points on different cutting paths of the workpiece. In yet another example, any two different sub-beams, after being focused by objective lens 1400, can form explosion points at different locations on the same cutting path of the workpiece. In the latter two examples, the explosion points corresponding to any two different sub-beams can be at the same depth of the workpiece or at different depths of the workpiece. For any sub-beam, without spherical aberration compensation, there is a problem of energy focusing difficulties due to spherical aberration; using a sub-spherical aberration compensation element can help solve this problem.

[0037] like Figure 1 As shown, the spherical aberration compensation assembly 1300 may include a predetermined number of sub-spherical aberration compensation elements 1301, 1302, 1303, ..., 130N. The spherical aberration compensation assembly 1300 can be used to compensate for the spherical aberration of sub-beams passing through the corresponding sub-spherical aberration compensation elements, thereby enabling each sub-beam to be focused by the objective lens 1400 to form a burst point at a predetermined location on the workpiece. Exemplarily, but not limitingly, the sub-beams adjusted by the spherical aberration compensation assembly 1300 may be parallel to each other. Exemplarily, each sub-spherical aberration compensation element in the spherical aberration compensation assembly 1300 may be a single lens or a combination of lenses. The surface of each lens may be, but is not limited to, spherical and / or aspherical mirrors. The materials and coatings of the sub-spherical aberration compensation elements may be selected to meet the wavelength and energy density requirements corresponding to the laser 1100. The wavelength corresponding to laser 1100 can refer to the target wavelength band, i.e., the wavelength band of the laser beam used by the system, such as infrared 1000nm~1600nm, green light 500nm~550nm, or ultraviolet 250nm~360nm, etc. Each sub-spherical aberration compensation element in the spherical aberration compensation assembly 1300 can use a coating layer suitable for the target wavelength band to refract the sub-beams, allowing the same sub-beam to be focused more concentratedly at the same position after passing through the objective lens.

[0038] Figure 2Fig. 1 shows a schematic diagram of focusing of a light beam when a spherical aberration compensation assembly is not included in an optical system for laser cutting according to an embodiment of the present application; Figure 3 Fig. 2 shows a schematic diagram of focusing of a light beam when a spherical aberration compensation assembly is included in an optical system for laser cutting according to an embodiment of the present application. Figure 2 As shown in Fig. 1, in an optical system for laser cutting, when a spherical aberration compensation assembly is not included, after any sub-beam is focused by an objective lens to a workpiece, a focal point cannot be formed at the same position of the workpiece (for example, the focal points O1, O2, O3 shown in Fig. 1). Figure 2 As shown in Fig. 2, in an optical system for laser cutting, when a spherical aberration compensation assembly is included, after any sub-beam is focused by an objective lens to a workpiece, a focal point can be formed at the same position of the workpiece (for example, the focal point O' shown in Fig. 2). Figure 3 As shown in Fig. 2, in an optical system for laser cutting, when a spherical aberration compensation assembly is included, after any sub-beam is focused by an objective lens to a workpiece, a focal point can be formed at the same position of the workpiece (for example, the focal point O' shown in Fig. 2). Figure 3 Wherein, ΔZ can represent a lowering height of the objective lens 1400, and ΔH can represent a depth at which the sub-beam is actually focused inside the workpiece, which is related to a refractive index of the workpiece.

[0039] Since the above scheme is a laser non-contact processing scheme, it has the advantages of no contact pollution and no mechanical deformation to the workpiece. In addition, since the above scheme adopts laser internal focusing modification technology, the modification area can be controlled within 10 μm, and the material loss is almost negligible. When designing a wafer chip, the size can be reduced as much as possible, so it also has the advantage of saving material cost. By using the spherical aberration compensation assembly in the embodiment of the present application, the focusing range of each sub-beam focused inside the workpiece can be more concentrated, the energy release direction of the focal point of the laser focused inside the workpiece can be adjusted, and the energy density of the focal point area can be improved, thereby effectively increasing the depth of the blasting area inside the material, reducing the cutting times, and further improving the cutting efficiency.

[0040] The optical system for laser cutting according to the embodiment of the present application can adjust the light beam incident to the objective lens through the spherical aberration compensation assembly to compensate the spherical aberration, thereby improving the stability of the modification layer, so that when cutting thicker materials, the cutting times or the cutting layers do not need to be increased, and better cutting effect can be obtained by using fewer cutting times or cutting layers, thereby effectively improving the efficiency of laser cutting.

[0041] Exemplarily, the optical system for laser cutting further includes a first light beam angle adjusting assembly 1500 arranged along the light path direction, the first light beam angle adjusting assembly 1500 is located between the spherical aberration compensation assembly 1300 and the light beam processing element 1200, and the first light beam angle adjusting assembly 1500 can include a predetermined number of sub-adjusting units, the predetermined number of sub-adjusting units correspond to the predetermined number of sub-beams one by one, and each sub-adjusting unit is used to adjust the transmission angle of the corresponding sub-beam.

[0042] As shown in Fig. 1, in an optical system for laser cutting, when a spherical aberration compensation assembly is not included, after any sub-beam is focused by an objective lens to a workpiece, a focal point cannot be formed at the same position of the workpiece (for example, the focal points O1, O2, O3 shown in Fig. 1). Figure 1As shown, the first light beam angle adjustment assembly 1500 can include a predetermined number of sub-adjustment units 1501, 1502, 1503,..., 150N. The predetermined number of sub-adjustment units corresponds to the predetermined number of sub-beams one-to-one. For example, if 10 sub-beams are obtained after the light beam processing element 1200 is processed, then the number of sub-adjustment units is also 10. The first light beam angle adjustment assembly 1500 can be arranged between the spherical aberration compensation assembly 1300 and the light beam processing element 1200. The first light beam angle adjustment assembly 1500 can be used to adjust the angle of each sub-beam emitted from the light beam processing element 1200, so that each sub-beam can propagate according to a predetermined transmission angle. Exemplarily but not limitatively, each sub-beam after the first light beam angle adjustment assembly 1500 can be parallel to each other. Exemplarily, each sub-adjustment unit in the first light beam angle adjustment assembly 1500 can be a mirror suitable for the target waveband, so as to adjust each sub-beam into a parallel beam. The target waveband refers to the waveband of the laser beam used by the system, for example, infrared 1000nm-1600nm, green 500nm-550nm, or ultraviolet 250nm-360nm, etc. Each sub-adjustment unit in the first light beam angle adjustment assembly 1500 can use a coating layer suitable for the target waveband to facilitate the reflection of the sub-beam.

[0043] According to the above technical solution, the transmission angle of the corresponding sub-beam can be adjusted by each sub-adjustment unit in the first light beam angle adjustment assembly. In this way, it can be ensured that each sub-beam can accurately enter the subsequent optical element (for example, each sub-beam shaping element in the first light beam shaping assembly described below) along the desired angle, and this angle adjustment helps to form an optical path with smaller space occupation, which helps to reduce the volume of the entire optical system.

[0044] Exemplarily, each sub-adjustment unit in the first light beam angle adjustment assembly 1500 is a mirror, and the transmission angle of the sub-beam corresponding to the mirror is adjusted by adjusting the angle of the mirror.

[0045] In one embodiment, for example Figure 1 Each sub-adjustment unit 1501, 1502, 1503,..., 150N in the first light beam angle adjustment assembly 1500 can be a mirror. The transmission angle of the sub-beam corresponding to the mirror is adjusted by adjusting the angle of the mirror. For example, adjusting the mirror 1501 can adjust the transmission angle of the corresponding sub-beam, so that the sub-beam can be vertically incident on the sub-beam shaping element 1601.

[0046] According to the above technical solution, the transmission angle of each sub-beam can be adjusted without complex cost, which is more economical and practical.

[0047] Exemplarily, the sub-beams reflected by the mirrors in the first beam angle adjustment assembly 1500 are parallel.

[0048] In one embodiment, for example Figure 1 , the sub-beams reflected by the mirrors 1501, 1502, 1503,..., 150N in the first beam angle adjustment assembly 1500 are parallel.

[0049] According to the above technical solution, the sub-beams reflected by the mirrors in the first beam angle adjustment assembly 1500 are parallel, so that the sub-beams emitted from the first beam angle adjustment assembly 1500 will not be too dispersed, and will not occupy more space, which is conducive to improving the compactness of the optical system. Of course, this embodiment is optional, and when needed, the angles of the mirrors in the first beam angle adjustment assembly 1500 can be adjusted so that the sub-beams emitted from at least two mirrors are not parallel to each other. In this case, the subsequent optical elements can adjust their receiving angles according to the emission light paths of the corresponding mirrors, so that they can receive the sub-beams reflected by the corresponding mirrors.

[0050] Exemplarily, the optical system 1000 for laser cutting can further include a first beam shaping assembly 1600 disposed along the light path direction, the first beam shaping assembly 1600 being located between the spherical aberration compensation assembly 1300 and the beam processing element 1200, the first beam shaping assembly 1600 can include a predetermined number of sub-beam shaping elements, the predetermined number of sub-beam shaping elements corresponding to the predetermined number of sub-beams one-to-one, each sub-beam shaping element being used for shaping the corresponding sub-beam.

[0051] Referring to Figure 1 , in the case where the optical system 1000 for laser cutting includes the first beam angle adjustment assembly 1500, the first beam shaping assembly 1600 can be disposed between the spherical aberration compensation assembly 1300 and the first beam angle adjustment assembly 1500. The sub-beam shaping elements in the first beam shaping assembly 1600 correspond to the sub-adjustment units in the first beam angle adjustment assembly 1500 one-to-one. Each sub-beam shaping element in the first beam shaping assembly 1600 is used for receiving the sub-beam emitted from the corresponding sub-adjustment unit.

[0052] Each sub-beam shaping element is configured to shape a corresponding sub-beam so that the sub-beam exiting the sub-beam shaping element has a preset optical parameter. The optical parameters corresponding to any two sub-beam shaping elements can be the same or different. The optical parameters can be set to any suitable parameters as needed, and the present application does not limit this. The sub-beam shaping elements in the first beam shaping assembly 1600 correspond one-to-one to the sub-spherical aberration compensation elements in the spherical aberration compensation assembly 1300, and the shaped sub-beam exiting any sub-beam shaping element can be incident into the corresponding sub-spherical aberration compensation element for spherical aberration compensation.

[0053] In one embodiment, each sub-beam shaping element in the first beam shaping assembly 1600 can be a beam expander. Exemplarily, each sub-beam shaping element in the first beam shaping assembly 1600 can be an electrically driven beam expander, which facilitates automatic adjustment of the optical parameters corresponding to each sub-beam shaping element by a control unit (e.g., the third controller). Of course, each sub-beam shaping element in the first beam shaping assembly 1600 can also be a manually controlled beam expander, and the user can manually adjust the optical parameters corresponding to each sub-beam shaping element. The first beam shaping assembly 1600 can include sub-beam shaping elements 1601, 1602, 1603,..., 160N, and the predetermined number of sub-beam shaping elements correspond one-to-one to the predetermined number of sub-adjustment units 1501, 1502, 1503,..., 150N. By adjusting the optical parameters corresponding to each sub-beam shaping element, such as the diameter and divergence angle of the beam, the focal depth of each sub-beam can be adjusted. In the case of the same optical parameters, the focal depths of the beams are also the same; conversely, in the case of different optical parameters, the focal depths of the beams are also different.

[0054] According to the above technical solution, through each sub-beam shaping element in the first beam shaping assembly, the sub-beam corresponding to each sub-beam shaping element can be shaped so that each shaped sub-beam can be incident at the desired depth of the workpiece after being collected by the objective lens.

[0055] Exemplarily, each sub-beam shaping element in the first beam shaping assembly 1600 is a beam expander, and the beam expander meets the wavelength and energy density requirements of the laser, and the expansion ratio of the beam expander is in the range of [1 times, 8 times].

[0056] In one embodiment, with reference to Figure 1The sub-beam shaping elements 1601, 1602, 1603, …, 160N in the first beam shaping assembly 1600 can each be an expander mirror. The expander mirror can be designed to meet the wavelength and corresponding energy density requirements of the laser 1100. For example, as described above, the laser 1100 emits a laser beam in a target wavelength band, such as infrared 1000 nm-1600 nm, or green 500 nm-550 nm, or ultraviolet 250 nm-360 nm, etc. The operating wavelength band of the expander mirror can include the target wavelength band described above. Exemplarily, the expansion ratio of the expander mirror can be in the range of [1 times, 8 times].

[0057] According to the above technical solution, the shaping of the sub-beam is realized by the expander mirror, the expander mirror has a large range of optical parameter adjustment for the beam and is simple and convenient to adjust, and can meet the shaping requirements of various lasers, and has a wide range of applications.

[0058] Exemplarily, the beam processing element 1200 is specifically configured to adjust the laser beam into a predetermined number of sub-beams and emit the corresponding sub-beams one by one at a preset interval.

[0059] In one embodiment, the beam processing element 1200 can adjust the laser beam into a predetermined number of sub-beams. For example, the laser beam can be adjusted into 10 sub-beams. The 10 sub-beams can be emitted one by one at a preset time interval. The preset time interval can be set according to a specific application scenario, which can be optionally set in advance by a user. For example, a sub-beam can be emitted every 2 seconds.

[0060] According to the above technical solution, the beam processing element 1200 can adjust the laser beam into a predetermined number of sub-beams and emit the corresponding sub-beams one by one at a preset interval, which helps to ensure that the energy density of each sub-beam remains constant and can meet the requirements of the application scenario of time-sharing cutting.

[0061] Exemplarily, the beam processing element 1200 is an acousto-optic deflector, the variable deflection angle of the acousto-optic deflector is greater than or equal to 1 mrad, and the modulation frequency of the acousto-optic deflector is in the range of [10 MHz, 500 MHz].

[0062] In one embodiment, the acousto-optic deflector can realize the emission of the laser beam one by one at a predetermined time interval to form a plurality of sub-beams. The material of the acousto-optic deflector can be selected according to the optical properties of the object to be processed and the wavelength requirements of the corresponding laser 1100. The acousto-optic deflector can be selected to have a variable deflection angle greater than or equal to 1 mrad and a modulation frequency in the range of [10 MHz, 500 MHz].

[0063] According to the technical scheme, the acousto-optic deflector has the advantage of high response, so that the switching efficiency of the cutting light path of the optical system is high, which helps to further improve the laser cutting efficiency and helps to improve the stability of the system.

[0064] Exemplarily, the optical system for laser cutting can further include a first controller communicatively connected with the acousto-optic deflector, configured to control the deflection angle θ of the laser beam by controlling the modulation frequency f of the acousto-optic deflector, so as to obtain a sub-beam corresponding to the angle θ.

[0065] The first controller and the acousto-optic deflector can be connected and communicated through any existing or future possible wired connection mode or wireless connection mode.

[0066] In one embodiment, based on the first controller, the modulation frequency f of the acousto-optic deflector is controlled to make the laser beam deflect by an angle θ, so that it can just enter each sub-adjustment unit of the corresponding first beam angle adjustment assembly 1500. The parameter φ[f, θ] corresponding to each sub-beam can be controlled by the first controller to switch the laser beam to enter the corresponding sub-adjustment unit. For example, by modulating the parameter φ1[f1, θ1], the frequency f1 of the acousto-optic deflector is modulated to make the laser beam deflect by an angle θ1, so that the laser beam is deflected to the incident light path of the sub-adjustment unit 1501. Based on the incident light path, the laser beam is adjusted by the sub-adjustment unit 1501 and then vertically and centrally incident to the corresponding sub-beam shaping element 1601 or sub-spherical aberration compensation element 1301.

[0067] According to the technical scheme, the first controller is communicatively connected with the acousto-optic deflector, so that the modulation parameter of the acousto-optic deflector can be controlled in real time, thereby ensuring that the sub-beam corresponding to the angle can be obtained. In this way, the efficiency of modulating the laser beam is improved.

[0068] Exemplarily, the optical system for laser cutting can further include a second beam shaping assembly 1700 arranged between the laser 1100 and the beam processing element 1200, configured to adjust the optical parameters of the laser beam emitted from the laser, so that the adjusted optical parameters of the laser beam can meet the incident requirements of the incident light of the beam processing element 1200.

[0069] As Figure 1As shown, the optical system 1000 for laser cutting may further include a second beam shaping assembly 1700. In one embodiment, the second beam shaping assembly 1700 may be disposed between the laser 1100 and the beam processing element 1200. Exemplarily and not limitingly, the second beam shaping assembly 1700 may include a third reflector 1710, a beam expander 1720, a fourth reflector 1730, and a focusing lens 1740. It is understood that the third reflector 1710 and / or the fourth reflector 1730 may be omitted. For example, the outgoing light path of the laser 1100 may coincide with the incoming light path of the beam expander 1720, in which case it is not necessary to use the third reflector 1710 to reflect the laser beam emitted by the laser 1100. The beam emitted by the laser 1100 is adjusted by the second beam shaping assembly 1700 to adjust the diameter and divergence angle of the beam to meet the incident light requirements of the beam processing element 1200. For example, the aforementioned incident requirement could refer to a beam diameter of 6 mm and an incident angle perpendicular to the center of the beam processing element 120°. Optionally, the diameter and divergence angle of the laser beam can be automatically adjusted by a fourth controller, or they can be manually adjusted according to the user's needs.

[0070] According to the above technical solution, the laser beam emitted by the laser can be adjusted to meet the incident light requirements of the beam processing element through the second beam shaping component. This facilitates the adaptation to various lasers and helps to improve the application range of optical systems used for laser cutting.

[0071] For example, each sub-spherical aberration compensation element in the spherical aberration compensation assembly 1300 is a single lens or a combination of lenses, and each lens of each sub-spherical aberration compensation element is a spherical lens or an aspherical lens.

[0072] Optionally, such as Figure 1 As shown, each sub-spherical aberration compensation element 1301, 1302, 1303, ..., 130N in the spherical aberration compensation assembly 1300 can be a single lens or a combination of lenses, and each lens of each sub-spherical aberration compensation element can be a spherical lens or an aspherical lens.

[0073] According to the above technical solution, the above-mentioned ball difference compensation component has a simple structure, is easy to implement, and has a low cost.

[0074] For example, the optical system 1000 for laser cutting may further include: a second beam angle adjustment component 1800 disposed between the spherical aberration compensation component 1300 and the objective lens 1400, for converging all compensated sub-beams output by the spherical aberration compensation component 1300 onto the objective lens 1400.

[0075] In one embodiment, such as Figure 1As shown, the second light beam angle adjustment assembly 1800 can be arranged between the spherical aberration compensation assembly 1300 and the objective lens 1400. The second light beam angle adjustment assembly 1800 can converge the sub light beams passing through the sub spherical aberration compensation elements 1301, 1302, 1303, 1304, …, 130N to the objective lens 1400.

[0076] According to the above technical solution, based on the second light beam angle adjustment assembly 1800, it can be ensured that the converged sub light beams can be vertically incident on the objective lens.

[0077] Exemplarily, the second light beam angle adjustment assembly 1800 includes a first mirror and at least one beam combining lens. The first mirror is arranged on an exit light path of an outermost sub spherical aberration compensation element among the predetermined number of sub spherical aberration compensation elements and is used for reflecting the corresponding sub light beam. The at least one beam combining lens is arranged on an exit light path of each of the remaining sub spherical aberration compensation elements one by one and is used for reflecting the sub light beam exiting from the corresponding sub spherical aberration compensation element. The first beam combining lens adjacent to the first mirror is further used for allowing the light beam reflected by the first mirror to pass through. Each of the remaining beam combining lenses is further used for allowing the light beam exiting from the previous beam combining lens to pass through. Any beam combining lens is used for combining the transmitted light passing through the beam combining lens and the reflected light reflected by the beam combining lens onto the same light path.

[0078] Referring again to Figure 1 , the second light beam angle adjustment assembly 1800 can include a first mirror 1810 and beam combining lenses 1821, 1822, 1823, …, 182M, where M=N-1. The first mirror 1810 is arranged on an exit light path of the sub spherical aberration compensation element 1301. The first mirror 1810 can reflect the light ray exiting from the sub spherical aberration compensation element 1301 onto the beam combining lens 1821 adjacent to the first mirror 1810. The beam combining lenses 1821, 1822, 1823, …, 182M can respectively reflect the light rays exiting from the sub spherical aberration compensation elements 1302, 1303, 1304, …, 130N. In addition, each beam combining lens can also allow the light beam exiting from the previous lens to pass through. For example, the beam combining lens 1821 can transmit the light beam reflected by the first mirror 1810, and the remaining beam combining lenses 1822, 1823, …, 182M can respectively transmit the light beam exiting from the previous beam combining lens. Each beam combining lens can combine the corresponding transmitted light and reflected light onto the same light path and exit.

[0079] According to the above technical solution, through the combination of the first mirror and the beam combining lens, the sub light beams from the sub light beam shaping elements can be converged onto the same light path, so as to facilitate further converging of the light beams onto the subsequent objective lens.

[0080] Exemplarily, the second beam angle adjusting assembly 1800 can further include a second mirror 1830, the first mirror 1810 is fixed, and the light propagating along the exit light path of the first mirror 1810 is vertically centrally incident on the objective lens 1400 after being reflected by the second mirror 1830, and the optical system 1000 for laser cutting can further include a second controller and at least one pneumatic guide rail, at least one beam combining lens is correspondingly arranged on the at least one pneumatic guide rail, and the second controller is communicatively connected with the at least one pneumatic guide rail, so as to adjust the exit light path of the corresponding beam combining lens to coincide with the exit light path of the first mirror 1810 by controlling the movement and / or rotation of any pneumatic guide rail.

[0081] As shown in Figure 1 The second mirror 1830 is arranged between the beam combining lens 182M and the objective lens 1400, and can reflect the light beam from the beam combining lens 182M into the objective lens 1400. At the same time, the incident light path of the second mirror 1830 is the same as the exit light path of the first mirror 1810. By adjusting the angle of the second mirror 1830, the angle of the light beam reflected into the objective lens 1400 can be adjusted. The second mirror 1830 is optional. For example, the objective lens 1400 can be directly arranged on the exit light path of the beam combining lens 182M, and in this case, the second mirror 1830 can not be arranged.

[0082] Exemplarily, in the case where the first mirror 1810 and the second mirror 1830 are arranged, the angles of the first mirror 1810 and the second mirror 1830 can be adjusted in advance, for example, the directions of the respective normal lines can be adjusted so that the light theoretically exiting from the first mirror 1810 can be vertically centrally incident on the objective lens 1400 after propagating along the exit light path thereof to the second mirror 1830. After adjustment, the positions of the first mirror 1810 and the second mirror 1830 can be fixed. Subsequently, when the optical system 1000 for laser cutting is applied to any cutting scene, the exit light path of the first mirror 1810 can be taken as a reference, and the angle of any beam combining lens can be adjusted so that the exit light path of the beam combining lens can coincide with the exit light path of the first mirror 1810.

[0083] The optical system 1000 for laser cutting can further comprise a second controller and at least one pneumatic guide rail. Each beam-combining mirror 1821, 1822, 1823, …, 182M is arranged on a corresponding pneumatic guide rail. The second controller is communicatively connected with each pneumatic guide rail, for example, through any wired and / or or wireless communication manner. The second controller can adjust the exit light path of the corresponding beam-combining mirror to coincide with the exit light path of the first mirror 1810 by controlling the movement and / or rotation of any pneumatic guide rail. For example, the second controller can make the exit light path of the beam-combining mirror 1821 coincide with the exit light path of the first mirror 1810 by translating the pneumatic guide rail corresponding to the beam-combining mirror 1821.

[0084] Any controller (e.g., the first controller, the second controller, the third controller, the fourth controller) described herein can be built with electronic elements such as comparators, registers, digital logic circuits, or implemented with processor chips such as single-chip microcomputers, microprocessors, digital signal processors (DSP), field programmable gate arrays (FPGA), programmable logic arrays (PLA), application-specific integrated circuits (ASIC), and their peripheral circuits. Illustratively, any controller described herein can include a combination of one or several of central processing units (CPU), graphic processing units (GPU), application-specific integrated circuits (ASIC), or other forms of processing units with data processing capability and / or instruction execution capability. In addition, any two controllers described herein can be the same controller or different controllers, including the case where all controllers are the same controller.

[0085] Illustratively, any of the at least one beam-combining mirror can be a flat mirror or a cubic mirror. In the case where the beam-combining mirror is a flat mirror, the position of the beam-combining mirror in the first direction can also be optionally adjusted by the pneumatic guide rail, i.e., the beam-combining mirror is controlled to translate in the first direction. The first direction refers to the direction of the exit light path of the sub-spherical-aberration-compensating element corresponding to the beam-combining mirror (i.e., the vertical direction shown in the figure). Figure 1 In the case where the beam-combining mirror is a flat mirror, adjusting the position of the beam-combining mirror in the first direction can also change the incident angle of the split beams reflected by the beam-combining mirror on the objective lens 1400.

[0086] In summary, the control unit can be used to adjust the position of the at least one beam-combining mirror to change the included angle between the optical axis of one or more of the at least one beam-combining mirror and the optical axis of the second mirror 1830 (i.e., its normal line) and / or change the position of one or more of the at least one beam-combining mirror in the first direction, so that the incident angles of the split beams reflected by the at least one beam-combining mirror on the objective lens 1400 are not the same.

[0087] According to the technical solution, the second mirror can reflect the light beam from the last beam-combining lens into the objective lens, so that the angle of the light beam reflected into the objective lens can be flexibly adjusted to meet different cutting requirements of the processed object.

[0088] Exemplarily, the at least one beam-combining lens has different transmittance and reflectance ratios.

[0089] Any two of the at least one beam-combining lens can have the same transmittance and reflectance ratio, or different transmittance and reflectance ratio, which can be set according to user requirements. Exemplarily, the transmittance and reflectance ratio of any beam-combining lens can be 50:50.

[0090] The at least one beam-combining lens has different transmittance and reflectance ratios, so that the focusing energy of the sub-beams corresponding to different beam-combining lenses is different, so that various laser processing application scenarios can be adapted.

[0091] The following will be described in conjunction with Figure 1 An exemplary process for laser cutting using the above-described optical system 1000 for laser cutting is described. First, a pulsed laser beam is emitted by the laser 1100, shaped to the required requirements by the second beam shaping assembly 1700, and then enters the acousto-optic deflector 1200. The acousto-optic deflector 1200 deflects the laser beam at different angles at different times, so that the obtained multiple sub-beams reach the mirrors of the first beam angle adjustment assembly 1500 in turn. The mirror angles of the mirrors are adjusted respectively, so that the sub-beams corresponding to the mirrors pass through the first beam shaping assembly 1600 and the spherical aberration compensation assembly 1300 vertically. The passing sub-beams are reflected by the first mirror 1810 or the corresponding beam-combining lens to the next beam-combining lens in turn and then converge to the second mirror 1830. Subsequently, the converged sub-beams pass through the objective lens 1400 vertically to focus, so that each sub-beam is focused without spherical aberration to form a burst point inside the processed object. The processed object is moved at high speed by the precision motion system, so that a burst layer can be formed inside the processed object, and then the cutting process is completed after the film is expanded.

[0092] According to another aspect of the present application, a laser processing device is also provided. The laser processing device can include a stage and an optical system for laser cutting as described above, wherein the stage is used to carry the processed object.

[0093] Exemplarily, the processed object can be a wafer. The wafer is placed on the stage, and when the stage moves, the wafer can be moved, so that it is convenient to form a modified layer inside the material.

[0094] According to a further aspect of the present application, there is also provided a laser processing method for emitting a laser beam to a processed article at a predetermined position of the processed article to form a focal point by using the optical system for laser cutting as described above.

[0095] Exemplarily, the above-described embodiments about emitting a laser beam to a processed article at a predetermined position of the processed article to form a focal point by using the optical system for laser cutting have been described in detail, and for the sake of brevity, will not be repeated here.

[0096] In the above technical solution, the light beam incident to the objective lens can be adjusted by the spherical aberration compensation assembly to compensate the spherical aberration, thereby improving the stability of the modified layer, so that when cutting thicker materials, the number of cutting times or the number of cutting layers does not need to be increased, and better cutting effect can be obtained by using fewer cutting times or cutting layers, thereby effectively improving the efficiency of laser cutting.

[0097] The entire cutting process is further described below by taking cutting of a silicon carbide wafer with a thickness of 350 μm as an example.

[0098] The conventional cutting layer number is more than 10, and under the premise that the motion speed of the precision motion platform is consistent, the present application can optimize the cutting of the silicon carbide wafer to 5 layers, and the laser cutting process can be completed in half the time.

[0099] Specifically, the laser 1100 selects an infrared picosecond pulse laser;

[0100] The laser 1100 emits an infrared pulse laser beam, and the laser beam passes through the second beam shaping assembly 1700, so that the laser beam is shaped to have a cross-sectional diameter of 2 mm and is vertically incident to the acousto-optic deflector 1200;

[0101] By modulating the frequency f1 of the acousto-optic deflector 1200, the laser beam is deflected by an angle θ1, so that the laser beam is deflected to a branch of the mirror 1501, which is defined as a first branch. With the first branch as a reference, the corresponding sub-beam is vertically incident to the sub-beam shaping element 1601 and the sub-spherical aberration compensation element 1301 after the angle of the sub-beam is adjusted by the mirror 1501, and then is vertically incident to the objective lens 1400 after the angle of the sub-beam is adjusted by the first mirror 1810 and the second mirror 1830, so that the first sub-beam is focused at a position 300 μm away from the incident surface inside the silicon carbide wafer;

[0102] By modulating the frequency f2 of the acousto-optic deflector 1200, the laser beam is deflected by an angle of θ2, so that the laser beam is deflected to the branch of the mirror 1502, defined as the second branch. After the corresponding sub-beam is adjusted by the mirror 1502, the sub-beam is parallel to the sub-beam of the first branch and is perpendicularly incident to the sub-beam shaping element 1602 and the sub-spherical aberration compensation element 1302, the beam combining lens 1821 is moved to the position as shown in FIG. 13B and the sub-beam of the second branch is adjusted to coincide with the sub-beam of the first branch, after passing through the second mirror 1830, the perpendicularly incident objective lens 1400, so that the second sub-beam is focused at a position 230 μm inside the silicon carbide wafer from the incident surface; Figure 1

[0103] By modulating the frequency f3 of the acousto-optic deflector 1200, the laser beam is deflected by an angle of θ3, so that the laser beam is deflected to the branch of the mirror 1503, defined as the third branch. After the corresponding sub-beam is adjusted by the mirror 1503, the sub-beam is parallel to the sub-beam of the first branch and is perpendicularly incident to the sub-beam shaping element 1603 and the sub-spherical aberration compensation element 1303, the beam combining lens 1822 is moved to the position as shown in FIG. 13C and the sub-beam of the third branch is adjusted to coincide with the sub-beam of the first branch, after passing through the second mirror 1830, the perpendicularly incident objective lens 1400, so that the third sub-beam is focused at a position 160 μm inside the silicon carbide wafer from the incident surface; Figure 1

[0104] By modulating the frequency f4 of the acousto-optic deflector 1200, the laser beam is deflected by an angle of θ4, so that the laser beam is deflected to the branch of the mirror 1504, defined as the fourth branch. After the corresponding sub-beam is adjusted by the mirror 1504, the sub-beam is parallel to the sub-beam of the first branch and is perpendicularly incident to the sub-beam shaping element 1604 and the sub-spherical aberration compensation element 1404, the beam combining lens 1823 is moved to the position as shown in FIG. 13D and the sub-beam of the fourth branch is adjusted to coincide with the sub-beam of the first branch, after passing through the second mirror 1830, the perpendicularly incident objective lens 1400, so that the fourth sub-beam is focused at a position 90 μm inside the silicon carbide wafer from the incident surface; Figure 1

[0105] By modulating the frequency f5 of the acousto-optic deflector 1200, the laser beam is deflected by an angle of θ5, so that the laser beam is deflected to the branch of the mirror 1505, defined as the fifth branch. After the corresponding sub-beam is adjusted by the mirror 1505, the sub-beam is parallel to the sub-beam of the first branch and is perpendicularly incident to the sub-beam shaping element 1605 and the sub-spherical aberration compensation element 1505, the beam combining lens 1824 is moved to the position as shown in FIG. 13E (assuming Figure 1 ​ ​​​​The fifth sub-beam is adjusted to coincide with the first sub-beam, and after passing through the second mirror 1830, the vertical center of the objective lens 1400 is incident, so that the fifth sub-beam is focused at a position 40 μm inside the silicon carbide wafer from the incident surface;

[0106] In addition, the wafer is driven by a high-precision motion system, so that the material forms a burst layer with different depths inside, and then the wafer is separated by mechanical dicing and film expansion.

[0107] Although the example embodiments have been described herein with reference to the accompanying drawings, it is to be understood that the example embodiments are only exemplary and are not intended to limit the scope of the present application. Those of ordinary skill in the art can make various changes and modifications without departing from the scope and spirit of the present application. All such changes and modifications are intended to be included within the scope of the present application as claimed in the appended claims.

[0108] Those of ordinary skill in the art can realize that the units and algorithm steps of each example described in connection with the embodiments disclosed herein can be realized by electronic hardware, or a combination of computer software and electronic hardware. Whether the functions are performed by hardware or software depends on the specific application and design constraints of the technical solution. Those of ordinary skill in the art can use different methods to implement the described functions for each specific application, but such implementation should not be considered beyond the scope of the present application.

[0109] It should be noted that the above embodiments illustrate the application rather than limit the application, and those skilled in the art can design alternative embodiments without departing from the scope of the appended claims. In the claims, any reference signs placed between parentheses shall not be construed as limiting the claims. The word "comprising" does not exclude the presence of elements or steps not listed in the claims. The word "a" or "an" preceding an element does not exclude the presence of a plurality of such elements. The application can be implemented by means of hardware comprising several distinct elements, and by means of a suitably programmed computer. In the unit claims enumerating several means, several of these means can be embodied by one and the same item of hardware. The use of the words first, second, and third, etc. does not imply any order. These words can be understood as names.

[0110] The above description is merely a specific implementation or description of the specific implementation of the present application, and the protection scope of the present application is not limited thereto. Any person skilled in the art can easily think of changes or replacements within the technical range disclosed by the present application, which should be covered within the protection scope of the present application. The protection scope of the present application should be subject to the protection scope of the claims.

Claims

1. An optical system for laser cutting, characterized in that, The optical system for laser cutting comprises, in sequence along an optical path direction, a laser, a beam processing element, a spherical aberration compensation assembly, and an objective lens, wherein The laser is configured to emit a laser beam; The beam processing element is configured to process the laser beam to obtain a predetermined number of sub-beams; The spherical aberration compensation assembly comprises a predetermined number of sub-spherical aberration compensation elements, which correspond one-to-one to the predetermined number of sub-beams, and each sub-spherical aberration compensation element is configured to compensate the spherical aberration of the sub-beam passing through the corresponding sub-spherical aberration compensation element; and the sub-beams compensated by the sub-spherical aberration compensation elements are focused by the objective lens to form a focal point at a predetermined position of the workpiece.

2. The optical system for laser cutting according to claim 1, characterized in that, The optical system for laser cutting further comprises a first beam angle adjustment assembly arranged along the optical path direction, the first beam angle adjustment assembly being arranged between the spherical aberration compensation assembly and the beam processing element, and the first beam angle adjustment assembly comprises a predetermined number of sub-adjustment units, which correspond one-to-one to the predetermined number of sub-beams, and each sub-adjustment unit is configured to adjust the transmission angle of the corresponding sub-beam.

3. The optical system for laser cutting according to claim 2, characterized in that, Each sub-adjustment unit in the first beam angle adjustment assembly is a mirror, and the transmission angle of the sub-beam corresponding to any mirror is adjusted by adjusting the angle of the mirror.

4. The optical system for laser cutting according to claim 3, characterized in that, The sub-beams reflected by each mirror in the first beam angle adjustment assembly are parallel.

5. The optical system for laser cutting of claim 1, wherein, The optical system for laser cutting further comprises a first beam shaping assembly arranged along the optical path direction, the first beam shaping assembly being arranged between the spherical aberration compensation assembly and the beam processing element, and the first beam shaping assembly comprises a predetermined number of sub-beam shaping elements, which correspond one-to-one to the predetermined number of sub-beams, and each sub-beam shaping element is configured to shape the corresponding sub-beam.

6. The optical system for laser cutting according to claim 5, characterized in that, Each sub-beam shaping element in the first beam shaping assembly is an expander, which satisfies the wavelength and energy density requirements of the laser, and the expansion ratio of the expander is in a range of 1 to 8.

7. The optical system for laser cutting according to any one of claims 1 to 6, characterized in that, The beam processing element is specifically configured to adjust the laser beam into the predetermined number of sub-beams and emit the corresponding sub-beam at a preset interval time.

8. The optical system for laser cutting according to claim 7, characterized in that, The beam processing element is an acousto-optic deflector, the variable deflection angle of the acousto-optic deflector is greater than or equal to 1 mrad, and the modulation frequency of the acousto-optic deflector is in a range of 10 MHz to 500 MHz.

9. The optical system for laser cutting according to claim 8, characterized in that, The optical system for laser cutting further comprises: A first controller communicatively connected to the acousto-optic deflector, configured to control the modulation frequency f of the acousto-optic deflector and the deflection angle θ of the laser beam, so as to obtain the sub-beam corresponding to the angle θ.

10. The optical system for laser cutting according to any one of claims 1 to 6, characterized in that, The optical system for laser cutting further comprises: A second beam shaping assembly arranged between the laser and the beam processing element, configured to adjust the optical parameters of the laser beam emitted from the laser, so that the optical parameters of the adjusted laser beam can meet the incidence requirements of the incident light of the beam processing element.

11. The optical system for laser cutting according to any one of claims 1 to 6, characterized in that, Each of the sub-spherical aberration compensation elements in the spherical aberration compensation assembly is a single lens or a combined lens group, and each lens of each sub-spherical aberration compensation element is a spherical lens or an aspherical lens.

12. The optical system for laser cutting according to any one of claims 1-6, characterized in that, The optical system for laser cutting further comprises: A second beam angle adjusting assembly is arranged between the spherical aberration compensation assembly and the objective lens, and is configured to converge all the compensated sub-beams output by the spherical aberration compensation assembly onto the objective lens.

13. The optical system for laser cutting of claim 12, wherein, The second beam angle adjusting assembly comprises a first reflecting mirror and at least one beam combining lens, The first reflecting mirror is arranged on an exit light path of an outermost sub-spherical aberration compensation element among the predetermined number of sub-spherical aberration compensation elements and is configured to reflect the corresponding sub-beam; The at least one beam combining lens is arranged on an exit light path of each of the remaining sub-spherical aberration compensation elements one by one, and is configured to reflect the sub-beam exiting from the corresponding sub-spherical aberration compensation element, wherein a first beam combining lens adjacent to the first reflecting mirror is further configured to allow the light beam reflected by the first reflecting mirror to pass through, each of the remaining beam combining lenses is further configured to allow the light beam exiting from the previous beam combining lens to pass through, and any beam combining lens is configured to combine the transmitted light passing through the beam combining lens and the reflected light reflected by the beam combining lens onto the same light path.

14. The optical system for laser cutting of claim 13, wherein, The second beam angle adjusting assembly further comprises a second reflecting mirror, the first reflecting mirror is fixed, and the light propagating along the exit light path of the first reflecting mirror is incident on the objective lens perpendicularly after being reflected by the second reflecting mirror, The optical system for laser cutting further comprises a second controller and at least one pneumatic guide rail, and the at least one beam combining lens is arranged on the at least one pneumatic guide rail one by one, The second controller is communicatively connected with the at least one pneumatic guide rail, and is configured to adjust the exit light path of the corresponding beam combining lens to coincide with the exit light path of the first reflecting mirror by controlling the movement and / or rotation of any pneumatic guide rail.

15. A laser processing apparatus characterized by comprising: The optical system for laser cutting further comprises a second controller and at least one pneumatic guide rail, and the at least one beam combining lens is arranged on the at least one pneumatic guide rail one by one, 16. A laser processing method characterized by, The second controller is communicatively connected with the at least one pneumatic guide rail, and is configured to adjust the exit light path of the corresponding beam combining lens to coincide with the exit light path of the first reflecting mirror by controlling the movement and / or rotation of any pneumatic guide rail. The optical system for laser cutting further comprises a second controller and at least one pneumatic guide rail, and the at least one beam combining lens is arranged on the at least one pneumatic guide rail one by one, The second controller is communicatively connected with the at least one pneumatic guide rail, and is configured to adjust the exit light path of the corresponding beam combining lens to coincide with the exit light path of the first reflecting mirror by controlling the movement and / or rotation of any pneumatic guide rail. The optical system for laser cutting further comprises a second controller and at least one pneumatic guide rail, and the at least one beam combining lens is arranged on the at least one pneumatic guide rail one by one, The second controller is communicatively connected with the at least one pneumatic guide rail, and is configured to adjust the exit light path of the corresponding beam combining lens to coincide with the exit light path of the first reflecting mirror by controlling the movement and / or rotation of any pneumatic guide rail. The optical system for laser cutting further comprises a second controller and at least one pneumatic guide rail, and the at least one beam combining lens is arranged on the at least one pneumatic guide rail one by one, The second controller is communicatively connected with the at least one pneumatic guide rail, and is configured to adjust the exit light path of the corresponding beam combining lens to coincide with the exit light path of the first reflecting mirror by controlling the movement and / or rotation of any pneumatic guide rail. The optical system for laser cutting further comprises a second controller and at least one pneumatic guide rail, and the at least one beam combining lens is arranged on the at least one pneumatic guide rail one by one, The second controller is communicatively connected with the at least one pneumatic guide rail, and is configured to adjust the exit light path of the corresponding beam combining lens to coincide with the exit light path of the first reflecting mirror by controlling the movement and / or rotation of any pneumatic guide rail.

Images