A laser processing system and a method for compensating for laser directivity offset

Abstract

This application discloses a laser processing system and a method for compensating for laser beam directionality deviation. The method includes: a laser; a beam splitting module for splitting the laser emitted by the laser into a first beam and a second beam, wherein the percentage of the intensity of the first beam relative to the total laser intensity is less than the percentage of the intensity of the second beam relative to the total laser intensity; a photoelectric detection module for receiving the first beam and generating a corresponding electrical signal; a shaping module for shaping the second beam, wherein the shaped second beam illuminates a working surface; a processing module, communicatively connected to the photoelectric detection module, for determining the deviation of the first beam based on the electrical signal output by the photoelectric detection module and generating a driving command based on the deviation; and a driving module, communicatively connected to the processing module, for adjusting the position of the shaping module according to the driving command sent by the processing module. This design enables online monitoring of laser beam deviation.

Description

Technical Field

[0001] This application relates to the field of laser technology, and in particular to a laser processing system and a method for compensating for laser pointing deviation. Background Technology

[0002] Laser pointing fluctuations are affected by temperature changes, mechanical vibrations, and component aging, causing optical axis shifts that disrupt the diffraction shaping rules of the DOE (Optical Diffraction Element). This results in significant energy deflection of the flat-top spot on the focusing stage, leading to uneven processing quality. Existing monitoring solutions are either costly (e.g., laser interferometers costing tens of thousands of yuan) or inefficient (manual inspection is slow and relies on experience), and there is no online, non-interfering monitoring solution, making it impossible to achieve simultaneous monitoring and processing. Summary of the Invention

[0003] This application provides a laser processing system and a method for compensating for laser pointing deviation, which can reduce monitoring costs and improve monitoring efficiency while achieving non-interference monitoring and processing synchronization.

[0004] This application provides a laser processing system, comprising: a laser for providing laser light; a beam splitting module for splitting the laser light emitted by the laser into a first beam and a second beam; wherein the percentage of the light intensity of the first beam to the total light intensity of the laser light is less than the percentage of the light intensity of the second beam to the total light intensity of the laser light; a photoelectric detection module for receiving the first beam and generating a corresponding electrical signal; a shaping module for shaping the second beam, wherein the shaped second beam irradiates a working surface; a processing module communicatively connected to the photoelectric detection module for determining the offset of the first beam based on the electrical signal output by the photoelectric detection module and generating a driving command based on the offset; and a driving module communicatively connected to the processing module for adjusting the position of the shaping module according to the driving command sent by the processing module.

[0005] In one embodiment, the laser processing system further includes a reflection module located in the optical path between the beam splitting module and the photoelectric detection module. The reflection module reflects the first beam multiple times and then directs it toward the photoelectric detection module to amplify the offset of the first beam.

[0006] In one embodiment, the reflection module includes a plurality of reflection units arranged sequentially along the optical path, each of the reflection units including two first reflectors arranged orthogonally, so that the direction of the incident beam and the direction of the outgoing beam of the reflection unit are opposite.

[0007] In one embodiment, the photoelectric detection module includes a four-quadrant photodiode, the first beam forms a light spot on the detection surface of the four-quadrant photodiode, and the four-quadrant photodiode generates the electrical signal corresponding to each quadrant region based on the distribution information of the light spot in each quadrant region.

[0008] In one embodiment, the processing module is specifically configured to: calculate, at least based on the electrical signal corresponding to each of the quadrant regions, the offset rate of the first beam relative to the center point of the four-quadrant photodetector diode in a first direction and a second direction; wherein the first direction and the second direction are the directions of the two coordinate axes of the four-quadrant photodetector diode; obtain a first optical path, a second optical path, and the dimensions of the four-quadrant photodetector diode in the first direction and the second direction; wherein the first optical path is the propagation distance of the laser along its theoretical optical axis from the laser to the detection surface of the four-quadrant photodetector diode, and the second optical path is the propagation distance of the laser along its theoretical optical axis from the laser to the incident surface of the shaping module; and, based on the dimensions of the four-quadrant photodetector diode in the first direction and the second direction, and the offset rate of the first beam in the first direction and the second direction, calculate the offset rate of the first beam relative to the center point of the four-quadrant photodetector diode in the first direction and the second direction, respectively; wherein the first optical path is the propagation distance of the laser along its theoretical optical axis from the laser to the incident surface of the shaping module; and, based on the dimensions of the four-quadrant photodetector diode in the first direction and the second direction, calculate the offset rate of the first beam relative to the center point of the four-quadrant photodetector diode in the first direction and the second direction, respectively ... The offset rate relative to the center point of the four-quadrant photodetector diode in the direction is used to determine the offset of the first beam relative to the center point of the four-quadrant photodetector diode in the first direction and the second direction, respectively. Based on the first optical path length, the second optical path length, and the offset of the first beam relative to the center point of the four-quadrant photodetector diode in the first direction and the second direction, the compensation amount of the second beam in the third direction and the fourth direction is determined. The relative offset of the second beam in the third direction is the same as that in the first direction of the first beam, and the relative offset of the second beam in the fourth direction is the same as that in the second direction of the first beam. Based on the compensation amount of the second beam in the third direction and the fourth direction, a drive command is generated to adjust the position of the shaping module to the target position in the third direction and the fourth direction.

[0009] In one embodiment, the beam splitting module includes a second reflector with light transmission function; wherein the second reflector is configured to split the incident laser into a transmitted first beam and a reflected second beam; wherein the light intensity of the first beam accounts for less than or equal to 2% of the total light intensity of the laser, the light intensity of the second beam accounts for more than or equal to 98% of the total light intensity of the laser, and the light transmittance of the second reflector does not exceed 2%.

[0010] A second aspect of this application provides a method for compensating for laser pointing offset, the method being applied in the processing module of the laser processing system described in any of the above embodiments, the method comprising: sending an activation command to the laser; in response to receiving an electrical signal sent by the photoelectric detection module, determining an offset of the first beam based on the electrical signal, and generating the driving command based on the offset.

[0011] In one embodiment, the photoelectric detection module includes a four-quadrant photodiode. The first beam forms a light spot on the detection surface of the four-quadrant photodiode. The four-quadrant photodiode generates an electrical signal corresponding to each quadrant region based on the distribution information of the light spot in each quadrant region. The step of determining the offset of the first beam based on the electrical signal and generating the driving command based on the offset includes: calculating the offset rate of the first beam relative to the center point of the four-quadrant photodiode in a first direction and a second direction, respectively, based at least on the electrical signal corresponding to each quadrant region; wherein the first direction and the second direction are the directions of the two coordinate axes of the four-quadrant photodiode; obtaining a first optical path, a second optical path, and the dimensions of the four-quadrant photodiode in the first direction and the second direction; wherein the first optical path is the optical path of the first beam, and the second optical path is the optical path of the second beam; and determining the offset of the first beam based on the electrical signal of the four-quadrant photodiode. Based on the dimensions in the first direction and the second direction, and the offset rate of the first beam relative to the center point of the four-quadrant photodetector diode in the first direction and the second direction, respectively, the offset amount of the first beam relative to the center point of the four-quadrant photodetector diode in the first direction and the second direction is determined; based on the first optical path, the second optical path, and the offset amount of the first beam relative to the center point of the four-quadrant photodetector diode in the first direction and the second direction, the compensation amount of the second beam in the third direction and the fourth direction is determined; wherein, the relative offset amount of the second beam in the third direction is the same as that of the first beam in the first direction, and the relative offset amount of the second beam in the fourth direction is the same as that of the first beam in the second direction; based on the compensation amount of the second beam in the third direction and the fourth direction, the drive command for driving the shaping module to adjust its position to the target position in the third direction and the fourth direction is generated.

[0012] In one embodiment, the electrical signals in the four quadrants of the photodetector module include a first electrical signal V00 corresponding to the first quadrant, a second electrical signal V01 corresponding to the second quadrant, a third electrical signal V10 corresponding to the third quadrant, and a fourth electrical signal V11 corresponding to the fourth quadrant. The offset rate of the first beam relative to the center point of the four-quadrant photodetector diode in the first direction and the second direction is calculated using the following formula: Δx = (V01 + V11 - V00 - V10) / (V00 + V01 + V10 + V11).

[0013] Δy = (V00 + V01 - V10 - V11) / (V00 + V01 + V10 + V11).

[0014] Wherein, Δx is the offset rate of the first beam relative to the center point of the four-quadrant photodetector diode in the first direction, and Δy is the offset rate of the first beam relative to the center point of the four-quadrant photodetector diode in the second direction.

[0015] In one embodiment, the offset of the first beam relative to the center point of the four-quadrant photodetector diode in the first direction and the second direction is calculated using the following formula: Δx_det = Δx × Kx.

[0016] Δy_det = Δy × Ky.

[0017] Wherein, Δx_det is the offset of the first beam relative to the center point of the four-quadrant photodetector diode in the first direction, Δy_det is the offset of the first beam relative to the center point of the four-quadrant photodetector diode in the second direction, Kx is the size of the four-quadrant photodetector diode in the first direction, and Ky is the size of the four-quadrant photodetector diode in the second direction.

[0018] In one embodiment, the compensation amount of the second beam in the third direction and the fourth direction is calculated using the following formula: X = (Δx_det × L2) / L1.

[0019] Y = (Δy_det × L2) / L1.

[0020] Wherein, X is the compensation amount of the second beam in the third direction, Y is the compensation amount of the second beam in the fourth direction, L1 is the first optical path, and L2 is the second optical path.

[0021] In one embodiment, the offset rate of the first beam relative to the center point of the four-quadrant photodetector diode in the first direction and the second direction is calculated using the following formula: Δx = (V01 + V11 - V00 - V10) / (V00 + V01 + V10 + V11) - Δx0.

[0022] Δy = (V00 + V01 - V10 - V11) / (V00 + V01 + V10 + V11) - Δy0.

[0023] Wherein, Δx0 is the zero-point offset rate of the first beam relative to the center point of the four-quadrant photodetector diode in the first direction, and Δy0 is the zero-point offset rate of the first beam relative to the center point of the four-quadrant photodetector diode in the second direction; the zero-point offset rate refers to the offset rate measured when the center point of the second beam coincides with the center point of the four-quadrant photodetector diode during the zero-point calibration of the laser.

[0024] In one embodiment, the dimensions of the four-quadrant photodetector diode in the first direction and the second direction are calculated using the following formula: Kx = Δx_det_standard / Δx_original.

[0025] Ky = Δy_det_standard / Δy_original.

[0026] Wherein, Kx is the dimension of the four-quadrant photodiode in the first direction, Ky is the dimension of the four-quadrant photodiode in the second direction, Δx_det_standard is the displacement generated by pushing the laser or the four-quadrant photodiode in the same direction as the third direction offset, Δy_det_standard is the displacement generated by pushing the laser or the four-quadrant photodiode in the same direction as the fourth direction offset, Δx_original is the test offset rate of the first beam relative to the center point of the four-quadrant photodiode in the first direction; Δx_original is the test offset rate of the first beam relative to the center point of the four-quadrant photodiode in the second direction.

[0027] Unlike existing technologies, the advantages of this application are as follows: This application splits the laser beam of the laser into a first beam and a second beam through a beam splitting module. The first beam is directed towards a photoelectric detection module, which generates an electrical signal based on the spot of the first beam on the photoelectric detection module. Then, the processing module determines the offset of the first beam based on the electrical signal and generates a drive command for the drive module to drive the shaping module. The shaping module shapes the second beam, and the position of the shaping module is adjusted by the drive module to ensure that the center of the spot of the second beam coincides with the center of the shaping module, thereby ensuring the laser processing quality of the working surface. This application adopts a non-interference monitoring and processing synchronization scheme, which reduces monitoring costs and improves monitoring efficiency. Attached Figure Description

[0028] To more clearly illustrate the technical solutions in the embodiments of this application, the accompanying drawings used in the description of the embodiments will be briefly introduced below. Obviously, the drawings described below are only some embodiments of this application. For those skilled in the art, other drawings can be obtained based on these drawings without creative effort, wherein: Figure 1 This is a schematic diagram of one embodiment of the laser processing system of this application; Figure 2 This is a flowchart illustrating the compensation method of this application; Figure 3 yes Figure 2 A flowchart illustrating one embodiment of step S200. Detailed Implementation

[0029] The technical solutions of the embodiments of this application will be clearly and completely described below with reference to the accompanying drawings. Obviously, the described embodiments are only a part of the embodiments of this application, and not all of the embodiments. Based on the embodiments of this application, all other embodiments obtained by those of ordinary skill in the art without creative effort are within the scope of protection of this application.

[0030] It should be noted that the terms "first" and "second" in this application are used for descriptive purposes only and should not be construed as indicating or implying relative importance or implicitly specifying the number of indicated technical features. Therefore, a feature defined as "first" or "second" may explicitly or implicitly include at least one of that feature. In the description of this application, "multiple" means at least two, such as two, three, etc., unless otherwise explicitly specified. Furthermore, the terms "comprising" and "having," and any variations thereof, are intended to cover non-exclusive inclusion. For example, a process, method, system, product, or apparatus that includes a series of steps or units is not limited to the listed steps or units, but may optionally include steps or units not listed, or may optionally include other steps or units inherent to these processes, methods, products, or apparatuses.

[0031] See Figure 1 , Figure 1 This is a schematic diagram of one embodiment of the laser processing system of this application. The first aspect of this application provides a laser processing system, which includes a laser 1, a beam splitting module 2, a photoelectric detection module 3, a shaping module 4, a processing module (not shown) and a driving module (not shown).

[0032] Laser 1 is used to provide laser light. Laser 1 can output a laser beam with a specific wavelength and power. After being modulated and shaped by subsequent optical elements, it is used for high-precision micromachining.

[0033] Beam splitting module 2 is used to split the laser emitted by laser 1 into a first beam and a second beam. The intensity of the first beam constitutes a smaller percentage of the total laser intensity than the intensity of the second beam. Beam splitting module 2 can divide the laser beam into two optical paths: a main optical path for processing and a monitoring optical path for real-time monitoring. In other words, the first beam enters the monitoring optical path, and the second beam enters the main optical path. The percentage of the first beam's intensity in the total laser intensity is less than that of the second beam. This can be understood as the first beam's intensity being greater than 0% and the second beam's intensity being less than 100%. This ensures successful beam splitting for simultaneous monitoring and processing, while also reducing the intensity required for monitoring, thus providing more laser energy for processing and guaranteeing processing quality.

[0034] The photoelectric detection module 3 is used to receive the first beam and generate a corresponding electrical signal. Utilizing its sensitive photoelectric properties, the photoelectric detection module 3 can accurately capture the position information of the light spot that the first beam hits on the detection surface of the photoelectric detection module 3, even if the light intensity of the first beam is relatively low, and convert the slight shift of the light spot into a high-resolution electrical signal.

[0035] The shaping module 4 is used to shape the second beam, which then illuminates the working surface 5. The shaping module 4 employs, for example, a diffractive optical element (DOE), which can convert the Gaussian beam into a flat-top spot or a specific energy distribution to ensure energy uniformity in the processing area. The second beam after shaping has a uniform energy distribution. Of course, if the laser beam itself has a directional deviation, its shaping effect will be significantly degraded.

[0036] The processing module is communicatively connected to the photoelectric detection module 3. It determines the offset of the first beam based on the electrical signal output by the photoelectric detection module 3 and generates a driving command based on the offset. Different laser beam offsets cause both the first and second beams to shift synchronously, and the relative offset depends on the laser beam offset. Since the relative offsets of the first and second beams are the same, after the photoelectric detection module 3 detects the electrical signal of the first beam, it sends the signal to the processing module. The processing module determines whether the first beam has shifted based on the signal. If the first beam has shifted, it indicates that the second beam also has a synchronous shift, requiring the generation of a corresponding compensation command. This compensation command is the subsequent command used to drive the shaping module. If the first beam has no shift, the second beam also has no shift, and the processing module determines that no compensation is needed and does not send a driving command.

[0037] The drive module is communicatively connected to the processing module and is used to adjust the position of the shaping module 4 according to the drive commands sent by the processing module. The drive module is always in a state of receiving commands from the processing module and responding to the drive commands in real time. The drive module and the shaping module 4 are mechanically connected. The drive module can drive the shaping module 4 and compensate for the directional deviation of the second beam by adjusting the position of the shaping module 4 in multiple directions. Thus, while calibrating the directional deviation, the shaping effect of the shaping module 4 is improved simultaneously.

[0038] In summary, this application utilizes the beam splitting module 2 to divide the laser beam of the laser 1 into a first beam and a second beam. The photoelectric detection module 3 monitors the offset of the first beam in real time. Then, the processing module determines the offset of the second beam based on the offset of the first beam, thereby controlling the driving module to drive the shaping module 4 to perform displacement compensation, so that the center point of the second beam spot coincides with the center of the shaping module. This achieves dual optimization of position compensation and shaping effect. At the same time, online real-time monitoring combined with the above-mentioned dynamic closed-loop calibration reduces monitoring costs without reducing processing quality.

[0039] In one embodiment, the laser processing system further includes a reflection module 6, which is located in the optical path between the beam splitting module 2 and the photoelectric detection module 3. The reflection module 6 reflects the first beam multiple times and then directs it toward the photoelectric detection module 3. The reflection module 6 is used to amplify the offset of the first beam.

[0040] Specifically, the reflection module 6 changes the propagation direction of the first beam, enabling the photoelectric detection module 3 to receive the first beam at a reasonable installation position. At the same time, through multiple reflections, the small angular deviation of the laser beam is amplified by the propagation path length of the first beam, thereby forming a more significant spot displacement on the photoelectric detection module 3. This ensures that the photoelectric detection module 3 can accurately detect the electrical signal representing the displacement of the center point of the first beam relative to the center point of the detection surface of the photoelectric detection module 3.

[0041] Furthermore, the reflection module 6 includes a plurality of reflection units 60 arranged sequentially along the optical path. Each reflection unit 60 includes two first reflective mirrors 600 arranged orthogonally so that the incident beam of the reflection unit 60 is opposite to the direction of the outgoing beam.

[0042] Specifically, each reflecting unit 60 contains two orthogonally arranged first reflecting mirrors 600. One first reflecting mirror 600 receives the incident beam and then reflects it to the other first reflecting mirror 600, which in turn reflects it, resulting in the direction of the final outgoing beam being completely opposite to that of the incident beam. Multiple reflecting units 60 are arranged sequentially along the optical path, continuously reflecting the first beam multiple times, thereby reducing the propagation length of the first beam in a single direction and effectively compressing the overall optical path space, making the laser processing system structure more compact. Preferably, each first reflecting mirror 600 forms a 45° angle with both the incident and outgoing beams, ensuring that the incident and outgoing beams of each first reflecting mirror 600 are orthogonal.

[0043] Of course, in some other implementations, the first reflector 600 of each reflective unit 60 may not be exactly the same, the number may be flexibly adjusted according to the actual optical path constraints, and the angle may not be 45°.

[0044] In one embodiment, the photoelectric detection module 3 includes a four-quadrant photodetector diode. A first beam forms a light spot on the detection surface of the four-quadrant photodetector diode. The four-quadrant photodetector diode generates an electrical signal corresponding to each quadrant region based on the distribution information of the light spot in each quadrant region.

[0045] Specifically, for example, in Figure 1 In the diagram, three directions are set up in pairs orthogonal arrangement: the X direction, the Y direction, and the Z direction. The detection surface of the four-quadrant photodiode is on the YZ plane. In the coordinate system formed by the Y and Z directions with the center point of the four-quadrant photodiode as the origin, each of the four quadrants is provided with a photodiode. After receiving the light signal, each photodiode generates its own electrical signal.

[0046] Furthermore, the photoelectric detection module 3 also includes a signal amplification circuit and an analog-to-digital conversion module. The signal amplification circuit is used to amplify the electrical signal generated by the photodetector diode, while the analog-to-digital conversion module converts the amplified analog electrical signal into a digital signal.

[0047] In one embodiment, the beam splitting module 2 includes a second reflector with light transmission function; wherein the second reflector is configured to split the incident laser into a transmitted first beam and a reflected second beam; wherein the light transmittance of the second reflector does not exceed 2%.

[0048] Specifically, the second reflector, equipped with light transmission capability, reflects the vast majority of the laser beam to the main optical path, allowing only ≤2% of the laser to transmit to the monitoring optical path. The transmittance of the second reflector can be 2%, 1.5%, 1%, or 0.5%, but must be greater than 0% to ensure sufficient weak transmitted light for real-time monitoring. The intensity of the first beam accounts for less than or equal to 2% of the total laser intensity, while the intensity of the second beam accounts for greater than or equal to 98%. The intensity percentage of the first beam is extremely low, for example, 2%, 1%, or 0.5% of the total laser intensity, while the intensity percentage of the second beam is extremely high, for example, 98%, 99%, or 99.5%. This maximizes the retention of energy in the main optical path, reduces the impact of monitoring on processing, and ensures processing quality.

[0049] In one embodiment, the laser processing system further includes a third reflector 7, a beam expander 8, and a field mirror 9. The third reflector 7 is located in the optical path between the shaping module 4 and the beam splitting module 2. The third reflector 7 is used to adjust the propagation direction of the second beam so that the second beam can be directed toward the working surface 5. The beam expander 8 is located in the optical path between the third reflector 7 and the shaping module 4. The beam expander 8 is used to enlarge the spot size of the second beam to match the incident aperture of the shaping module 4. The field mirror 9 is located between the shaping module 4 and the working surface 5. The field mirror 9 is used to further calibrate the beam focusing characteristics to ensure that the processed spot has the optimal energy density distribution and spatial consistency on the working surface 5.

[0050] In one embodiment, the driving module can apply a driving force to the shaping module 4 to displace its incident surface, causing the shaping module 4 to translate along the two-dimensional direction of the incident surface to calibrate the second beam. For example, in Figure 1 In the middle, the driving module drives the shaping module 4 to translate in the Y and Z directions.

[0051] It should be noted that, Figure 1As just one implementation, in other implementations, the optical path can be adjusted so that the detection surface of the photoelectric detection module 3, the incident surface of the shaping module 4, and the working surface 5 can all be any two orthogonal planes of XY, XZ, or YZ.

[0052] In one embodiment, the processing module includes a host computer and a microprocessor. The microprocessor is used to acquire data provided by the analog-to-digital converter and calculate the offset, while the host computer is used to calculate the compensation amount and output drive instructions to the drive module.

[0053] Combination Figure 1 and Figure 2 , Figure 2 This is a flowchart illustrating the compensation method of this application. A second aspect of this application provides a method for compensating for laser pointing offset, which is applied in the processing module of any of the aforementioned laser processing systems. The method includes: S100: Send an activation command to laser 1.

[0054] Specifically, the processing module first sends an activation command to the laser 1 to turn on the laser. After the laser 1 responds, it outputs a laser beam. At this time, the photoelectric detection module 3 will capture the transmitted light spot signal in real time and generate an electrical signal to be transmitted to the processing module.

[0055] S200: In response to receiving an electrical signal sent by the photoelectric detection module 3, determine the offset of the first beam based on the electrical signal, and generate a drive command based on the offset.

[0056] Specifically, after receiving the electrical signal sent by the photoelectric detection module 3, the processing module analyzes and processes the electrical signal data, calculates the offset of the first beam, and then generates a control command based on the offset to drive the shaping module 4 to translate, thereby realizing the compensation control command for the second beam offset.

[0057] Furthermore, the photoelectric detection module 3 includes a four-quadrant photodetector diode. The first beam forms a light spot on the detection surface of the four-quadrant photodetector diode. The four-quadrant photodetector diode generates an electrical signal corresponding to each quadrant region based on the distribution information of the light spot in each quadrant region. In step S200 above, see [reference needed]. Figure 3 , Figure 3 yes Figure 2 A flowchart illustrating one embodiment of step S200, the step of generating a drive command based on an electrical signal includes: S210: Calculate the offset rate of the first beam relative to the center point of the four-quadrant photodetector diode in the first direction and the second direction, respectively, based on the electrical signal corresponding to each quadrant region; wherein the first direction and the second direction are the directions of the two coordinate axes of the four-quadrant photodetector diode.

[0058] Specifically, the first and second directions are the directions of the two coordinate axes of the four-quadrant photodetector diode. It should be noted that... Figure 1 In this embodiment, the first and second directions are divided into the Y and Z directions. In other embodiments, with different arrangements of the structures, the first and second directions can also be the X and Y directions, or the X and Z directions, respectively. If the first beam deflects on the four-quadrant photodetector diodes, the electrical signals of the four photodetector diodes will also differ. By calculating these four different electrical signals, the deflection rate of the first beam relative to the center point of the four-quadrant photodetector diodes in the first and second directions can be determined.

[0059] Furthermore, the electrical signals in the four quadrants of the photoelectric detection module 3 include the first electrical signal V00 corresponding to the first quadrant, the second electrical signal V01 corresponding to the second quadrant, the third electrical signal V10 corresponding to the third quadrant, and the fourth electrical signal V11 corresponding to the fourth quadrant. The offset rate of the first beam relative to the center point of the photoelectric detection diode in the first direction and the second direction is calculated using the following formula: Δx = (V01 + V11 - V00 - V10) / (V00 + V01 + V10 + V11).

[0060] Δy = (V00 + V01 - V10 - V11) / (V00 + V01 + V10 + V11).

[0061] Where Δx is the offset rate of the first beam relative to the center point of the four-quadrant photodetector diode in the first direction, and Δy is the offset rate of the first beam relative to the center point of the four-quadrant photodetector diode in the second direction.

[0062] Specifically, the above formula uses a normalization algorithm to calculate the offset rate of the center of the first beam spot relative to the center point of the four-quadrant photodetector diode, ensuring that the values ​​of Δx and Δy are limited to [ Within [1, +1], to eliminate the influence of light intensity fluctuations. Δx and Δy are both unitless relative offset coefficients, representing only the "offset direction and proportion of the light spot center relative to the center of the four-quadrant photodetector diode". For example, Δx = +0.2 only indicates that the light spot of the first beam is offset in the positive direction of the first direction of the four-quadrant photodetector diode, and the offset proportion is 20% of the effective range of the four-quadrant photodetector diode in the first direction. This value cannot be directly used for displacement adjustment of the drive module.

[0063] S220: Obtain the dimensions of the first optical path, the second optical path, and the four-quadrant photodetector diode in the first and second directions; wherein, the first optical path is the propagation distance of the laser along its theoretical optical axis from the laser 1 to the detection surface of the four-quadrant photodetector diode, and the second optical path is the propagation distance of the laser along its theoretical optical axis from the laser 1 to the incident surface of the shaping module 4.

[0064] Specifically, the first and second optical paths are theoretically the laser propagation distances without deviation. These two optical paths are fixed values ​​after the laser processing system is installed; they can also be considered design parameters. Therefore, both specific values ​​are directly stored in the host computer of the processing module and are not lost when power is off. The dimensions of the four-quadrant photodetector diode in the first and second directions are its physical dimensions. For example, they can be equal to half the effective photosensitive surface length of the two coordinate axes of the four-quadrant photodetector diode. For instance, a four-quadrant photodetector diode with a 5mm photosensitive surface has dimensions of 2.5mm in both the first and second directions. Of course, the physical dimensions of the four-quadrant photodetector diode in the first and second directions can also be determined through calibration.

[0065] Furthermore, the dimensions of the four-quadrant photodetector diode in the first and second directions are calculated using the following formulas: Kx = Δx_det_standard / Δx_original; Ky = Δy_det_standard / Δy_original; Wherein, Kx is the dimension of the four-quadrant photodiode in the first direction, Ky is the dimension of the four-quadrant photodiode in the second direction, Δx_det_standard is the displacement generated by pushing the laser or the four-quadrant photodiode in the same direction as the third direction offset, Δy_det_standard is the displacement generated by pushing the laser or the four-quadrant photodiode in the same direction as the fourth direction offset, Δx_original is the test offset rate of the first beam relative to the center point of the four-quadrant photodiode in the first direction; Δx_original is the test offset rate of the first beam relative to the center point of the four-quadrant photodiode in the second direction.

[0066] Specifically, the above implementation method does not rely on the specific physical dimensions of the four-quadrant photodiode in the first and second directions. Instead, it uses a testing method to drive the laser or the four-quadrant photodiode to apply a physical offset to the first beam. This physical offset can be directly measured. Combined with the electrical signal generated by the four-quadrant photodiode, the processing module calculates the test offset rate, thereby calculating the ratio to deduce the dimensions Kx of the four-quadrant photodiode in the first direction and the dimensions Ky of the four-quadrant photodiode in the second direction. This method can avoid nominal size deviations caused by manufacturing errors or batch differences.

[0067] S230: Based on the dimensions of the four-quadrant photodetector diode in the first direction and the second direction, and the offset rate of the first beam relative to the center point of the four-quadrant photodetector diode in the first direction and the second direction, determine the offset of the first beam relative to the center point of the four-quadrant photodetector diode in the first direction and the second direction, respectively.

[0068] Specifically, the offset rate is a normalization coefficient. It can be considered as the relative position ratio of the offset of the center point of the light spot to the center of the four-quadrant photodetector diode. Based on the size of the four-quadrant photodetector diode in each of the two directions, the offset of the corresponding first beam can be further calculated. This offset represents the actual offset of the first beam.

[0069] Furthermore, the offset of the first beam relative to the center point of the four-quadrant photodetector diode in the first and second directions is calculated using the following formula: Δx_det = Δx × Kx.

[0070] Δy_det = Δy × Ky.

[0071] Where Δx_det is the offset of the first beam relative to the center point of the four-quadrant photodiode in the first direction, Δy_det is the offset of the first beam relative to the center point of the four-quadrant photodiode in the second direction, Kx is the size of the four-quadrant photodiode in the first direction, and Ky is the size of the four-quadrant photodiode in the second direction.

[0072] Specifically, this conversion process transforms dimensionless Δx and Δy into physically meaningful offsets Δx_det and Δy_det, which can be understood as being obtained based on the physical dimensions of the photosensitive surface of the four-quadrant photodetector diode, thereby determining the actual offset of the light spot at the first light speed on the four-quadrant photodetector diode.

[0073] S240: Based on the first optical path, the second optical path, and the offset of the first beam relative to the center point of the four-quadrant photodetector diode in the first and second directions, determine the compensation amount of the second beam in the third direction and in the fourth direction; wherein, the relative offset of the second beam in the third direction is the same as that in the first direction of the first beam, and the relative offset of the second beam in the fourth direction is the same as that in the second direction of the first beam.

[0074] Specifically, the third and fourth directions of the second beam can be exactly the same as the first and second directions of the first beam. Of course, in other embodiments, the third and fourth directions can also be two directions different from the first and second directions. These third and fourth directions can be any one of Y and Z directions, X and Y directions, or X and Z directions. Since the beam splitting module 2 does not affect the beam deflection, the first and second beams have the same deflection angle. Therefore, the compensation amount of the second beam can be determined using the difference between the first and second optical paths and the offset of the first beam.

[0075] Furthermore, firstly, the deflection angle θx of the laser optical axis in the first direction and the third direction is calculated. Since Δx_det is much smaller than the first optical path L1, complex trigonometric function calculations are avoided and the relationship is reduced to a linear one. It can be approximated that θx≈Δx_det / L1. Similarly, since Δy_det is much smaller than the first optical path L1, it can be approximated that θy≈Δy_det / L1.

[0076] Next, calculate the compensation amount of the second beam at the incident surface of the shaping module 4. The third direction compensation amount is: X = θx × L2 ≈ (Δx_det × L2) / L1, and the fourth direction compensation amount is: Y = θy × L2 ≈ (Δy_det × L2) / L1.

[0077] S250: Based on the compensation amount of the second beam in the third direction and the fourth direction, generate drive commands for driving the shaping module to adjust its position to the target position in the third direction and the fourth direction.

[0078] Specifically, the processing module generates drive commands to control the drive module based on the compensation amount of the second beam in the third direction and the fourth direction, thereby controlling the drive module to move the shaping module 4 in the third direction and the fourth direction, and finally adjusting the center of the second beam spot to the center position of the shaping module 4.

[0079] In one embodiment, the offset rate of the first beam relative to the center point of the four-quadrant photodetector diode in the first direction and the second direction is calculated using the following formula: Δx = (V01 + V11 - V00 - V10) / (V00 + V01 + V10 + V11)-Δx0; Δy = (V00 + V01 - V10 - V11) / (V00 + V01 + V10 + V11)-Δy0; Wherein, Δx0 is the zero-point offset rate of the first beam relative to the center point of the four-quadrant photodetector diode in the first direction, and Δy0 is the zero-point offset rate of the first beam relative to the center point of the four-quadrant photodetector diode in the second direction; the zero-point offset rate refers to the offset rate measured when the center point of the second beam coincides with the center point of the four-quadrant photodetector diode during the zero-point calibration of the laser.

[0080] Specifically, unlike the offset rate determined earlier, the formula here also includes two zero-point offset rates, Δx0 and Δy0. Their main function is to eliminate the initial zero-point offset caused by manufacturing tolerances, circuit temperature drift, and installation stress in the four-quadrant detector. Specifically, the laser is adjusted so that the spot of the first beam falls precisely on the center point of the four-quadrant photodetector diode. The output values ​​of Δx0 and Δy0 of the processing module at this time are recorded and stored. They can be directly called for zero-point calibration compensation during subsequent execution.

[0081] In one embodiment, the processing module in the laser processing system of this application is specifically used to perform the above steps S210 to S250.

[0082] The above description is merely an embodiment of this application and does not limit the patent scope of this application. Any equivalent structural or procedural transformations made using the content of this application's specification and drawings, or direct or indirect applications in other related technical fields, are similarly included within the patent protection scope of this application.

Claims

1. A laser processing system, characterized in that, include: Laser, used to provide laser light; A beam splitting module is used to split the laser emitted by the laser into a first beam and a second beam; wherein the intensity of the first beam accounts for a smaller percentage of the total intensity of the laser than the intensity of the second beam accounts for a smaller percentage of the total intensity of the laser. A photoelectric detection module is used to receive the first beam and generate a corresponding electrical signal; A shaping module is used to shape the second beam, wherein the shaped second beam illuminates the working surface; The processing module is communicatively connected to the photoelectric detection module and is used to determine the offset of the first beam based on the electrical signal output by the photoelectric detection module, and generate a driving command based on the offset. The driving module is communicatively connected to the processing module and is used to adjust the position of the shaping module according to the driving instructions sent by the processing module.

2. The laser processing system according to claim 1, characterized in that, The laser processing system also includes: A reflection module is located in the optical path between the beam splitting module and the photoelectric detection module. The reflection module reflects the first beam multiple times and then directs it toward the photoelectric detection module to amplify the offset of the first beam.

3. The laser processing system according to claim 2, characterized in that, The reflection module includes multiple reflection units arranged sequentially along the optical path. Each reflection unit includes two orthogonally arranged first reflectors so that the incident beam and the outgoing beam of the reflection unit are in opposite directions.

4. The laser processing system according to claim 1, characterized in that, The photoelectric detection module includes a four-quadrant photodetector diode. The first beam forms a light spot on the detection surface of the four-quadrant photodetector diode. The four-quadrant photodetector diode generates an electrical signal corresponding to each quadrant region based on the distribution information of the light spot in each quadrant region.

5. The laser processing system according to claim 4, characterized in that, The processing module is specifically used for: At least the offset rate of the first beam relative to the center point of the four-quadrant photodetector diode is calculated in the first direction and the second direction, respectively, based on the electrical signal corresponding to each quadrant region; wherein the first direction and the second direction are the directions of the two coordinate axes of the four-quadrant photodetector diode; Obtain the first optical path, the second optical path, and the dimensions of the four-quadrant photodetector diode in the first direction and the second direction; wherein, the first optical path is the propagation distance of the laser along its theoretical optical axis from the laser to the detection surface of the four-quadrant photodetector diode, and the second optical path is the propagation distance of the laser along its theoretical optical axis from the laser to the incident surface of the shaping module; Based on the dimensions of the four-quadrant photodetector diode in the first direction and the second direction, and the offset rate of the first beam relative to the center point of the four-quadrant photodetector diode in the first direction and the second direction, the offset of the first beam relative to the center point of the four-quadrant photodetector diode in the first direction and the second direction is determined respectively. Based on the first optical path, the second optical path, and the offset of the first beam relative to the center point of the four-quadrant photodetector diode in the first and second directions, the compensation amount of the second beam in the third and fourth directions is determined; wherein, the relative offset of the third direction of the second beam is the same as that of the first beam in the first direction, and the relative offset of the fourth direction of the second beam is the same as that of the first beam in the second direction. Based on the compensation amount of the second beam in the third direction and the fourth direction, a drive command is generated for adjusting the position of the shaping module to the target position in the third direction and the fourth direction.

6. The laser processing system according to claim 1, characterized in that, The beam splitting module includes a second reflector with light transmission function; wherein the second reflector is configured to split the incident laser into a transmitted first beam and a reflected second beam; wherein the light intensity of the first beam accounts for less than or equal to 2% of the total light intensity of the laser, the light intensity of the second beam accounts for more than or equal to 98% of the total light intensity of the laser, and the light transmittance of the second reflector does not exceed 2%.

7. A method for compensating for laser pointing deviation, characterized in that, The method is applied in the processing module of the laser processing system according to any one of claims 1 to 6, and the method includes: Send an activation command to the laser; In response to receiving the electrical signal sent by the photoelectric detection module, the offset of the first beam is determined based on the electrical signal, and the driving command is generated based on the offset.

8. The compensation method according to claim 7, characterized in that, The photoelectric detection module includes a four-quadrant photodetector diode. The first beam forms a light spot on the detection surface of the four-quadrant photodetector diode. The four-quadrant photodetector diode generates the electrical signal corresponding to each quadrant region based on the distribution information of the light spot in each quadrant region. The step of determining the offset of the first beam based on the electrical signal and generating the driving command based on the offset includes: At least the offset rate of the first beam relative to the center point of the four-quadrant photodetector diode is calculated in the first direction and the second direction, respectively, based on the electrical signal corresponding to each quadrant region; wherein the first direction and the second direction are the directions of the two coordinate axes of the four-quadrant photodetector diode; Obtain the first optical path, the second optical path, and the dimensions of the four-quadrant photodetector diode in the first direction and the second direction; wherein, the first optical path is the optical path of the first beam, and the second optical path is the optical path of the second beam; Based on the dimensions of the four-quadrant photodetector diode in the first direction and the second direction, and the offset rate of the first beam relative to the center point of the four-quadrant photodetector diode in the first direction and the second direction, the offset of the first beam relative to the center point of the four-quadrant photodetector diode in the first direction and the second direction is determined respectively. Based on the first optical path, the second optical path, and the offset of the first beam relative to the center point of the four-quadrant photodetector diode in the first and second directions, the compensation amount of the second beam in the third and fourth directions is determined; wherein, the relative offset of the third direction of the second beam is the same as that of the first beam in the first direction, and the relative offset of the fourth direction of the second beam is the same as that of the first beam in the second direction. Based on the compensation amount of the second beam in the third direction and the fourth direction, a drive command is generated for adjusting the position of the shaping module to the target position in the third direction and the fourth direction.

9. The compensation method according to claim 7, characterized in that, The electrical signals in the four quadrants of the photoelectric detection module include a first electrical signal V00 corresponding to the first quadrant, a second electrical signal V01 corresponding to the second quadrant, a third electrical signal V10 corresponding to the third quadrant, and a fourth electrical signal V11 corresponding to the fourth quadrant. The offset rate of the first beam relative to the center point of the four-quadrant photodetector diode in the first direction and the second direction is calculated using the following formula: Δx = (V01 + V11 - V00 - V10) / (V00 + V01 + V10 + V11); Δy = (V00 + V01 - V10 - V11) / (V00 + V01 + V10 + V11); Wherein, Δx is the offset rate of the first beam relative to the center point of the four-quadrant photodetector diode in the first direction, and Δy is the offset rate of the first beam relative to the center point of the four-quadrant photodetector diode in the second direction.

10. The compensation method according to claim 9, characterized in that, The offset of the first beam relative to the center point of the four-quadrant photodetector diode in the first direction and the second direction is calculated using the following formula: Δx_det = Δx × Kx; Δy_det = Δy × Ky; Wherein, Δx_det is the offset of the first beam relative to the center point of the four-quadrant photodetector diode in the first direction, Δy_det is the offset of the first beam relative to the center point of the four-quadrant photodetector diode in the second direction, Kx is the size of the four-quadrant photodetector diode in the first direction, and Ky is the size of the four-quadrant photodetector diode in the second direction.

11. The compensation method according to claim 10, characterized in that, The compensation amount of the second beam in the third direction and the fourth direction is calculated using the following formula: X = (Δx_det × L2) / L1; Y = (Δy_det × L2) / L1; Wherein, X is the compensation amount of the second beam in the third direction, Y is the compensation amount of the second beam in the fourth direction, L1 is the first optical path, and L2 is the second optical path.

12. The compensation method according to claim 10, characterized in that, The offset rate of the first beam relative to the center point of the four-quadrant photodetector diode in the first direction and the second direction is calculated using the following formula: Δx = (V01 + V11 - V00 - V10) / (V00 + V01 + V10 + V11)-Δx0; Δy = (V00 + V01 - V10 - V11) / (V00 + V01 + V10 + V11)-Δy0; Wherein, Δx0 is the zero-point offset rate of the first beam relative to the center point of the four-quadrant photodetector diode in the first direction, and Δy0 is the zero-point offset rate of the first beam relative to the center point of the four-quadrant photodetector diode in the second direction; the zero-point offset rate refers to the offset rate measured when the center point of the second beam coincides with the center point of the four-quadrant photodetector diode during the zero-point calibration of the laser.

13. The compensation method according to claim 8, characterized in that, The dimensions of the four-quadrant photodetector diode in the first direction and the second direction are calculated using the following formula: Kx = Δx_det_standard / Δx_original; Ky = Δy_det_standard / Δy_original; Wherein, Kx is the dimension of the four-quadrant photodiode in the first direction, Ky is the dimension of the four-quadrant photodiode in the second direction, Δx_det_standard is the displacement generated by pushing the laser or the four-quadrant photodiode in the same direction as the third direction offset, Δy_det_standard is the displacement generated by pushing the laser or the four-quadrant photodiode in the same direction as the fourth direction offset, Δx_original is the test offset rate of the first beam relative to the center point of the four-quadrant photodiode in the first direction; Δx_original is the test offset rate of the first beam relative to the center point of the four-quadrant photodiode in the second direction.

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