Galvanometer system and light beam adjusting method

Abstract

The invention discloses a galvanometer system and a light beam adjusting method, and the galvanometer system comprises a laser generating device which is used for emitting a laser beam; the light beam adjusting module is used for adjusting the light beam diameter of the laser beam; the galvanometer module is used for adjusting the light beam position of the laser beam; the F-theta mirror is used for focusing the laser beam into a light spot; the upper computer is provided with a multi-axis galvanometer motion control card, and the multi-axis galvanometer motion control card is in communication connection with the light beam adjusting module and the galvanometer module; the upper computer is used for receiving a light beam adjusting instruction and inputting the light beam adjusting instruction into the multi-axis galvanometer motion control card, so that the multi-axis galvanometer motion control card sends instructions to the light beam adjusting module and the galvanometer module at the same time. The multi-axis galvanometer motion control card sends instructions to the light beam adjusting module and the galvanometer module at the same time so as to correspondingly adjust the laser beams, and therefore the time delay problem in the galvanometer system is solved, and the machining precision of the galvanometer system is improved.

Description

Technical Field

[0001] The present invention relates to the field of optical technology, and in particular to a galvanometer system and a light beam adjustment method. Background Art

[0002] During laser processing, the size of the laser focus spot determines the processing accuracy and energy density. Energy density and laser power meet: ; In the above formula, F is the energy density, P avg is the average power of the laser, r0 is the radius of the focused spot, f fre is the laser frequency. If it is a continuous laser, the value is 1. Here, when the energy laser focused spot is smaller, the impact range within a single point is smaller, indicating that the processing accuracy is higher and the energy density is greater. Conversely, when the focused spot is larger, the impact range is larger, indicating that the energy density is smaller. Therefore, the focused spot size can be changed according to different processing materials and processing requirements to meet different processing technology requirements.

[0003] like Figure 1 As shown, the existing laser galvanometer system includes a parallel beam size adjustment module 1, a galvanometer 2 and a focusing lens 3 in sequence along the propagation direction of the optical path. After the laser is emitted, it first reaches the parallel beam size adjustment module 1 to form a parallel beam, then passes through the galvanometer 2, and finally reaches the focusing lens 3 for focusing. In the existing laser galvanometer system, the parallel beam size adjustment module 1 plays a role in quickly adjusting the diameter size of the incident laser parallel beam. For example, the larger the radius of the laser beam before the incident focusing lens 3, the smaller the radius of the focused spot obtained after focusing through the focusing lens. Specifically, the parallel beam size adjustment module 1 includes a variable magnification beam expander group, which includes multiple lenses. The laser beam diameter can be adjusted by adjusting the spacing between different lenses.

[0004] The methods of adjusting the spacing between different lenses mainly include manual adjustment and ordinary electric control, but both of them have certain defects. For example, the manual adjustment method has the defects of low precision and slow response, which cannot meet the needs of high-precision and fast processing; for example, although the ordinary electric control method has greater precision and response speed than the manual adjustment method, it still does not meet the needs of high-speed galvanometer processing systems, especially the motor type and control method used, which will greatly limit the precision and response speed of galvanometer processing. And in terms of motor type, the motors currently used are mostly stepper motors or motors, and their precision cannot meet high standards. In addition, in terms of control methods, the protocol for controlling motor movement and the protocol for controlling the galvanometer are often two or more protocols, which will cause different control delays between the parallel beam size adjustment module and the galvanometer, and different control delays will cause the final processing result to lack sufficient precision and reliability, and will cause the overall galvanometer processing system to become more complex, the response speed to decrease, and the subsequent correction difficulty to increase.

[0005] This delay between the galvanometer and the beam expansion response will reduce the processing accuracy of the entire processing system. Therefore, designing a system that can achieve synchronous response of the galvanometer and the parallel beam size adjustment module in the galvanometer system is an urgent problem to be solved by those skilled in the art. Summary of the invention

[0006] The embodiments of the present invention provide a galvanometer system and a light beam adjustment method, which are intended to achieve synchronous response of the galvanometer system and improve the processing accuracy of the galvanometer system.

[0007] An embodiment of the present invention provides a galvanometer system, comprising: A laser generating device, used for emitting a laser beam; A beam adjustment module, used for receiving the laser beam and adjusting the beam diameter of the laser beam; A galvanometer module, used for receiving the laser beam and adjusting the beam position of the laser beam; An F-theta mirror is used to receive the laser beam whose beam diameter and beam position are adjusted, and focus the laser beam into a light spot; A host computer, wherein the host computer is provided with a multi-axis galvanometer motion control card, and the multi-axis galvanometer motion control card is respectively connected to the beam adjustment module and the galvanometer module for communication; The host computer is used to receive beam adjustment instructions and input the beam adjustment instructions into the multi-axis galvanometer motion control card, so that the multi-axis galvanometer motion control card sends corresponding beam adjustment instructions to the beam adjustment module and the galvanometer module at the same time.

[0008] Furthermore, one end of the beam adjustment module is connected to the laser generating device, and the other end is connected to one end of the galvanometer module, and the other end of the galvanometer module is connected to the F-theta mirror.

[0009] Furthermore, the beam adjustment module and the galvanometer module each include a plurality of signal pins or interfaces of different types.

[0010] Furthermore, the multi-axis galvanometer motion control card is provided with a plurality of main control chips, and each of the main control chips is respectively connected to a pin signal communication of the beam adjustment module and the galvanometer module.

[0011] Furthermore, the multi-axis galvanometer motion control card is respectively connected to the beam adjustment module and the galvanometer module in communication via the same communication protocol.

[0012] Furthermore, the communication protocol is the XY2-100 protocol or the SL2-100 protocol.

[0013] Furthermore, the beam adjustment module includes a plurality of voice coil motors, and each of the voice coil motors is configured with an optical lens.

[0014] Furthermore, the optical lenses configured for the plurality of voice coil motors are arranged in a line along the propagation direction of the light beam.

[0015] An embodiment of the present invention further provides a light beam adjustment method, which is applied to the galvanometer system as described in any one of the above items, and the method includes: The host computer receives the beam adjustment instruction and inputs the beam adjustment instruction into the multi-axis galvanometer motion control card; The multi-axis galvanometer motion control card simultaneously sends corresponding beam adjustment instructions to the beam adjustment module and the galvanometer module; The beam adjustment module and the galvanometer module adjust the laser beam accordingly according to the beam adjustment instructions received respectively.

[0016] The multi-axis galvanometer motion control card simultaneously sends corresponding beam adjustment instructions to the beam adjustment module and the galvanometer module, including: The multi-axis galvanometer motion control card sends corresponding beam adjustment instructions to the beam adjustment module and the galvanometer module simultaneously based on the same communication protocol.

[0017] The embodiment of the present invention provides a galvanometer system and a beam adjustment method, wherein the galvanometer system includes: a laser generating device, used to emit a laser beam; a beam adjustment module, used to receive the laser beam and adjust the beam diameter of the laser beam; a galvanometer module, used to receive the laser beam and adjust the beam position of the laser beam; an F-theta mirror, used to receive the laser beam whose beam diameter and beam position have been adjusted, and focus the laser beam into a light spot; a host computer, wherein the host computer is provided with a multi-axis galvanometer motion control card, and the multi-axis galvanometer motion control card is respectively communicated with the beam adjustment module and the galvanometer module; wherein the host computer is used to receive a beam adjustment instruction, and input the beam adjustment instruction into the multi-axis galvanometer motion control card, so that the multi-axis galvanometer motion control card sends the corresponding beam adjustment instruction to the beam adjustment module and the galvanometer module at the same time. The embodiment of the present invention sends beam adjustment instructions to the beam adjustment module and the galvanometer module simultaneously through the multi-axis galvanometer motion control card in the host computer to achieve a synchronous response of the galvanometer system, and enables the beam adjustment module and the galvanometer module to adjust the laser beam accordingly according to the beam adjustment instruction, so that the light spot finally focused by the F-theta mirror meets the requirements of the beam adjustment instruction. This not only solves the delay problem in the galvanometer system, enhances the overall processing coordination of the galvanometer system, but also improves the processing accuracy of the galvanometer system. BRIEF DESCRIPTION OF THE DRAWINGS

[0018] In order to more clearly illustrate the technical solutions of the embodiments of the present invention, the accompanying drawings required for use in the description of the embodiments will be briefly introduced below. Obviously, the accompanying drawings described below are some embodiments of the present invention. For ordinary technicians in this field, other accompanying drawings can be obtained based on these accompanying drawings without paying any creative work.

[0019] Figure 1 It is a structural schematic diagram of a laser galvanometer system in the prior art; Figure 2 A schematic structural diagram of a galvanometer system provided by an embodiment of the present invention; Figure 3 Another structural schematic diagram of a galvanometer system provided by an embodiment of the present invention; Figure 4 A schematic flow chart of a light beam adjustment method provided by an embodiment of the present invention. DETAILED DESCRIPTION

[0020] The following will be combined with the drawings in the embodiments of the present invention to clearly and completely describe the technical solutions in the embodiments of the present invention. Obviously, the described embodiments are part of the embodiments of the present invention, not all of the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by ordinary technicians in this field without creative work are within the scope of protection of the present invention.

[0021] It should be understood that when used in this specification and the appended claims, the terms "include" and "comprises" indicate the presence of described features, integers, steps, operations, elements and / or components, but do not exclude the presence or addition of one or more other features, integers, steps, operations, elements, components and / or combinations thereof.

[0022] It should also be understood that the terms used in this specification of the present invention are only for the purpose of describing specific embodiments and are not intended to limit the present invention. As used in the specification of the present invention and the appended claims, unless the context clearly indicates otherwise, the singular forms "a", "an" and "the" are intended to include plural forms.

[0023] It should be further understood that the term "and / or" used in the present description and the appended claims refers to and includes any and all possible combinations of one or more of the associated listed items.

[0024] See below Figure 2 , an embodiment of the present invention provides a galvanometer system, the galvanometer system comprising: A laser generating device 10, for emitting a laser beam; A beam adjustment module 20, used for receiving the laser beam and adjusting the beam diameter of the laser beam; The galvanometer module 30 is used to receive the laser beam and adjust the beam position of the laser beam; An F-theta mirror 40 is used to receive the laser beam after the beam diameter and the beam position are adjusted, and focus the laser beam into a light spot; A host computer 50, wherein the host computer 50 is provided with a multi-axis galvanometer motion control card 501, and the multi-axis galvanometer motion control card 501 is respectively connected to the beam adjustment module 20 and the galvanometer module 30 for communication; The host computer 50 is used to receive beam adjustment instructions and input the beam adjustment instructions into the multi-axis galvanometer motion control card 501, so that the multi-axis galvanometer motion control card 501 sends corresponding beam adjustment instructions to the beam adjustment module 20 and the galvanometer module 30 at the same time.

[0025] In this embodiment, the galvanometer system includes a laser generating device 10, a beam adjustment module 20, a galvanometer module 30, an F-theta mirror 40, and a host computer 50 provided with a multi-axis galvanometer motion control card 501. When the galvanometer system is working, the laser beam generated by the laser generating device 10 will be incident on the beam adjustment module 20 and the galvanometer module 30, and at the same time, the host computer 50 will send corresponding beam adjustment instructions to the beam adjustment module 20 and the galvanometer module 30 respectively through the multi-axis galvanometer motion control card 501, so that the beam adjustment module 20 and the galvanometer module 30 adjust the beam diameter, beam position, etc. of the laser beam according to the beam adjustment instructions received by each, so that the laser beam finally incident on the F-theta mirror 40 can be focused by the F-theta mirror 40 into a light spot that meets the requirements.

[0026] In this embodiment, the multi-axis galvanometer motion control card 501 in the host computer 50 simultaneously sends beam adjustment instructions to the beam adjustment module 20 and the galvanometer module 30 to achieve synchronous response of the galvanometer system, and enables the beam adjustment module 20 and the galvanometer module 30 to adjust the laser beam accordingly according to the beam adjustment instruction, so that the light spot generated by the final focusing of the F-theta mirror 40 meets the requirements of the beam adjustment instruction. This not only solves the delay problem in the galvanometer system, enhances the overall processing coordination of the galvanometer system, but also improves the processing accuracy of the galvanometer system. In addition, the galvanometer system provided in this embodiment is particularly suitable for high-precision industries such as 3D metal printing. In actual tests, for the processing of a single product, the processing efficiency of the galvanometer system provided in this embodiment can be increased by 2 times compared with the prior art.

[0027] In one embodiment, if Figure 3 As shown, one end of the beam adjustment module 20 is connected to the laser generating device 10 , and the other end is connected to one end of the galvanometer module 30 , and the other end of the galvanometer module 30 is connected to the F-theta mirror 40 .

[0028] In this embodiment, the laser generating device 10, the beam adjustment module 20, the galvanometer module 30 and the F-theta mirror 40 are connected in sequence along the propagation direction of the optical path, wherein the beam adjustment module 20 is mainly responsible for adjusting the initial parameters of the laser beam, including but not limited to the adjustment of the beam diameter and the divergence angle. After the preliminary adjustment of the beam adjustment module 20, the parameters of the laser beam are optimized, laying the foundation for the subsequent precise adjustment. The galvanometer module 30 is responsible for further adjusting the direction and position of the laser beam. According to the beam adjustment instruction, the galvanometer module 30 can quickly and accurately adjust the transmission path of the laser beam to ensure that the laser beam is accurately focused on the predetermined position of the F-theta mirror 40. As the final optical element, the F-theta mirror 40 focuses the adjusted laser beam and generates a light spot that meets the requirements. Through this collaborative adjustment mechanism, precise control of the laser beam is achieved, thereby improving the processing accuracy and efficiency of the galvanometer system.

[0029] In one embodiment, the beam adjustment module 20 and the galvanometer module 30 both include a plurality of signal pins or interfaces of different types.

[0030] Correspondingly, the multi-axis galvanometer motion control card 501 is provided with a plurality of main control chips, and each of the main control chips is respectively connected to a pin signal communication of the beam adjustment module 20 and the galvanometer module 30 .

[0031] In this embodiment, multiple types of signal pins or interfaces are respectively set on the beam adjustment module 20 and the galvanometer module 30, such as the clock signal CLK, the serial digital signal interface SDI, and the chip select signal CS, etc. At the same time, the multi-axis galvanometer motion control card 501 in this embodiment is provided with multiple main control chips, and each main control chip is connected to one of the signal pins. For example, the multi-axis galvanometer motion control is provided with three main control chips, wherein the first main control chip is connected to the clock signal pin in the beam adjustment module 20 and the galvanometer module 30, and is used to perform unified timing control on the beam adjustment module 20 and the galvanometer module 30, the second main control chip is connected to the serial digital signal interface in the beam adjustment module 20 and the galvanometer module 30, and is used to transmit corresponding beam adjustment instructions to the beam adjustment module 20 and the galvanometer module 30, etc., and the second main control chip is connected to the chip select signal pin in the beam adjustment module 20 and the galvanometer module 30, and is used to select to connect or disconnect with the beam adjustment module 20 and / or the galvanometer module 30.

[0032] In another embodiment, the multi-axis galvanometer motion control card 501 is respectively connected to the beam adjustment module 20 and the galvanometer module 30 through the same communication protocol.

[0033] Specifically, the communication protocol is the XY2-100 protocol or the SL2-100 protocol.

[0034] This embodiment is based on the multi-axis galvanometer motion control card 501, and can achieve the effect of simultaneously controlling the beam adjustment module 20 and the galvanometer module 30 through a set of communication protocols (such as the XY2-100 protocol or the SL2-100 protocol). This can avoid the problem of time delay between the beam adjustment module 20 and the galvanometer module 30, which in turn leads to the problem of reduced processing accuracy due to uncoordinated work of the entire processing system.

[0035] In a specific embodiment, the beam adjustment module 20 includes a plurality of voice coil motors, and each of the voice coil motors is equipped with an optical lens. Specifically, the optical lenses equipped with the plurality of voice coil motors are arranged in a line along the beam propagation direction.

[0036] Compared with the stepper motor used in the prior art, the voice coil motor used in this embodiment has the characteristics of simple structure, small size, high speed, high acceleration and fast response. Its working principle is that when a powered coil (conductor) is placed in a magnetic field, a force will be generated, and the magnitude of the force is proportional to the current applied to the coil. The voice coil motor manufactured based on this principle can move in a straight line or in an arc. In this embodiment, the optical lens is driven by the voice coil motor to adjust the beam diameter of the laser beam, which can not only overcome the time delay problem in the galvanometer system, but also further improve the processing accuracy of the galvanometer system.

[0037] In actual application scenarios, there are three voice coil motors, which are arranged in a row. Correspondingly, the optical lenses configured for the three voice coil motors are also arranged in a row. When the beam diameter needs to be adjusted, the multi-axis galvanometer motion control card 501 can send beam adjustment instructions to the three voice coil motors respectively, so that the three voice coil motors perform corresponding movements according to the beam adjustment instructions to drive the optical lens to move. In this way, the spacing between the three optical lenses can be adjusted, and then the beam diameter of the laser beam can be adjusted. Of course, in other application scenarios, it is also possible to consider setting more voice coil motors and optical lenses to meet different adjustment requirements, or to further improve the beam adjustment accuracy.

[0038] It should be clear that in the prior art, the galvanometer motion control card controlled by the galvanometer protocol can usually only correspond to 1 or 2 galvanometer axes, and in this embodiment, since the multi-axis galvanometer motion control card 501 is provided with multiple main control chips, more galvanometer axes can be controlled at the same time (for example, the x galvanometer axis and y galvanometer axis of the galvanometer module 30, and the three voice coil motors in the optical adjustment module, etc., so that the multi-axis galvanometer motion control card 501 described in this embodiment can achieve the effect of controlling 5 galvanometer axes at the same time). It can be understood that after setting up multiple main control chips in this embodiment, the control program on the multi-axis galvanometer motion control card 501 will naturally be adjusted so that multiple main control chips can participate in the operation, thereby improving the control effect. Furthermore, the control delay of multiple galvanometer axes controlled by the multi-axis galvanometer motion control card 501 can meet the preset requirements, such as less than 10us, by continuously optimizing the control card hardware and the supporting underlying program, so that the response speed of the galvanometer system can be further improved. During optimization, the function modules can be first written and tested on the multi-axis galvanometer motion control card 501, and then the objects that need to be optimized can be determined through the test results, such as replacing more sophisticated electronic components. At the same time, the signal instruction allocation of the multi-axis galvanometer motion control card 501 can also be optimized and iterated to improve the response speed and accuracy of the system. It should also be noted that the galvanometer motion control card in the prior art usually needs to use two different protocols to control the beam adjustment module 20 and the galvanometer module 30 respectively, for example Figure 1 The galvanometer motion control card controls the parallel beam size adjustment module through the R232 / USB protocol, and controls the galvanometer through the galvanometer protocol, which easily leads to delay problems. This embodiment is based on the improvement of the multi-axis galvanometer motion control card 501, and only needs to use one set of protocols to simultaneously control the beam adjustment module 20 and the galvanometer module 30, thereby effectively solving the delay problem.

[0039] For example, in the shoe mold 3D metal printing industry, for the sole mold, there are usually many fine patterns or lines, and there are also very flat surfaces. For fine patterns and lines, a smaller laser focusing spot is needed for processing, while for large flat surfaces, a larger laser focusing spot can be used for processing. In this regard, the existing 2D galvanometer can only be processed with a small focusing spot, which causes the overall processing efficiency to become very low. When the galvanometer system provided by the present embodiment is used for processing, the three-dimensional model of the sole mold can be first obtained through the host computer 50, and the three-dimensional model is automatically sliced ​​to identify and divide the patterns, lines and planes therein, and then the corresponding beam adjustment instructions can be generated according to the results of the identification and division, such as generating a beam adjustment instruction for reducing the beam diameter for patterns and lines, and generating a beam adjustment instruction for increasing the beam diameter for planes, thereby realizing the variable focusing spot function of the galvanometer system, thereby improving the processing efficiency of the galvanometer system.

[0040] Figure 4 A schematic flow chart of a light beam adjustment method provided in an embodiment of the present invention is provided. The method is applied to the galvanometer system as described above. The method specifically includes steps S101 to S103.

[0041] Step S101, the host computer 50 receives a beam adjustment instruction, and inputs the beam adjustment instruction into the multi-axis galvanometer motion control card 501; Step S102, the multi-axis galvanometer motion control card 501 sends corresponding beam adjustment instructions to the beam adjustment module 20 and the galvanometer module 30 at the same time; Step S103: the beam adjustment module 20 and the galvanometer module 30 adjust the laser beam accordingly according to the beam adjustment instructions received respectively.

[0042] In this embodiment, the multi-axis galvanometer motion control card 501 in the upper computer 50 simultaneously sends beam adjustment instructions to the beam adjustment module 20 and the galvanometer module 30 to achieve a synchronous response of the galvanometer system, and enables the beam adjustment module 20 and the galvanometer module 30 to adjust the laser beam accordingly according to the beam adjustment instruction, so that the light spot finally focused by the F-theta mirror 40 meets the requirements of the beam adjustment instruction. This not only solves the delay problem in the galvanometer system, enhances the overall processing coordination of the galvanometer system, but also improves the processing accuracy of the galvanometer system.

[0043] In a specific embodiment, the multi-axis galvanometer motion control card 501 simultaneously sends corresponding beam adjustment instructions to the beam adjustment module 20 and the galvanometer module 30, including: The multi-axis galvanometer motion control card 501 sends corresponding beam adjustment instructions to the beam adjustment module 20 and the galvanometer module 30 simultaneously based on the same communication protocol.

[0044] Based on the multi-axis galvanometer motion control card 501, it is possible to simultaneously control the beam adjustment module 20 and the galvanometer module 30 through a set of communication protocols (such as the XY2-100 protocol or the SL2-100 protocol). This can avoid the problem of time delay between the beam adjustment module 20 and the galvanometer module 30, which in turn leads to the problem of reduced processing accuracy of the entire processing system due to uncoordinated work.

[0045] In some optional embodiments, the host computer 50 is also equipped with a user interaction interface, through which the user can intuitively input beam adjustment instructions, such as specifying parameters such as the size, position or shape of the light spot. After receiving these instructions, the host computer 50 will immediately process them and convert them into signals that can be recognized by the multi-axis galvanometer motion control card 501, and then transmit these signals to the beam adjustment module 20 and the galvanometer module 30 at the same time. Throughout the process, the collaborative work between the host computer 50, the multi-axis galvanometer motion control card 501, the beam adjustment module 20 and the galvanometer module 30 ensures the rapidity and accuracy of the light spot adjustment. In addition, the galvanometer system is also highly flexible and scalable, and can be customized and optimized according to actual application requirements to meet the processing requirements of different fields.

[0046] For example, the host computer 50 can receive the voice command input by the user, and use the voice recognition module or software to perform voice recognition on the voice command using the corresponding voice recognition algorithm (such as a voice recognition model based on deep learning, etc.) to obtain the corresponding text content. Then, the natural language processing (NLP) technology is used to extract features of the text content, such as extracting key nouns (such as light spot, light beam, etc.), verbs (adjust, change, etc.) and qualifiers (size, position, etc.) through lexical analysis, and constructing appropriate feature vectors or syntax trees and other structures to accurately identify the content of the instruction about light spot adjustment. After obtaining the light beam adjustment instruction, it is necessary to further parse the instruction, and distinguish which parts are for beam diameter adjustment and which parts are related to beam position adjustment based on the semantic information, keywords, etc. contained in the instruction. For example, if the text contains expressions such as "increase the diameter of the light spot" and "reduce the thickness of the light beam", it can be classified as a beam diameter adjustment instruction; while contents such as "move the light spot to the left" and "adjust the beam position to the top" can be classified into a beam position adjustment instruction. Thus, the beam diameter adjustment instruction and the beam position adjustment instruction are divided. The beam diameter adjustment instruction and the beam position adjustment instruction are sent to the beam adjustment module and the galvanometer module respectively. For example, the instruction received by the host computer 50 is "move the beam to the coordinate (x = 10, y = 20)" or "translate the beam 5 units to the left and 3 units upward". For the former, the host computer 50 needs to extract the information of the target coordinates (10, 20), and for the latter, the host computer 50 needs to extract the horizontal and vertical displacements (-5 and 3, where it can be considered that the left direction is the negative direction and the upward direction is the positive direction).

[0047] In addition, after focusing the light spot through the F-theta mirror 40, the host computer 50 can collect relevant information of the light spot, such as the actual size and position of the light spot, through image recognition and other methods, and then optimize the processing program of the light beam adjustment instruction based on the actual information of the light spot to provide feedback, so that the subsequently generated light beam adjustment instruction is more accurate and reliable.

[0048] In actual application scenarios, the beam adjustment module 20 includes a plurality of voice coil motors, and each of the voice coil motors is configured with an optical lens. Specifically, the optical lenses configured with the plurality of voice coil motors are arranged in a line along the direction of beam propagation. When the voice coil motor is used to adjust the beam diameter, in order to ensure the adjustment accuracy so as to improve the overall processing accuracy of the galvanometer system, the voice coil motor is initialized and calibrated in advance, for example, the zero position of the voice coil motor is determined (that is, the optical lens is in a certain initial position, and the beam diameter corresponding to the position can be used as a reference value), and the driving circuit of the voice coil motor is parameterized, such as current limiting, speed control and other parameters, to ensure that the voice coil motor can run smoothly and accurately. Secondly, when the beam adjustment instruction sent by the multi-axis galvanometer motion control card 501 is received, it can be understood that the beam adjustment instruction is usually a voltage control signal for the voice coil motor, and its size and polarity determine the size and direction of the current in the voice coil motor. For example, if it is necessary to move the optical lens in the direction close to the light source to reduce the beam diameter, the voltage control signal will cause the current to pass through the coil of the voice coil motor to generate a force pointing in the direction of the light source. Subsequently, under the action of force, the mover of the voice coil motor drives the lens to move along the optical axis. Assuming that the beam diameter is to be reduced, the lens moves closer to the light source. Due to the change in the position of the optical lens, according to the optical principle mentioned above, the degree of beam convergence increases and the spot diameter becomes smaller. In this process, the movement speed and displacement of the voice coil motor are determined by the parameters of the control signal. For example, if the voltage corresponding to the voltage control signal is higher, the current in the voice coil motor will be larger, the force generated will be greater, and the lens movement speed will be faster; conversely, the optical lens movement speed will be slow.

[0049] Furthermore, in order to achieve more accurate beam diameter adjustment, a feedback mechanism can also be set. For example, a photodetector can be placed in the optical path to measure the beam diameter, and the measured actual beam diameter signal can be fed back to the host computer 50. The host computer 50 will continuously adjust the control signal sent to the voice coil motor drive circuit according to the difference between the set target beam diameter and the actual measured beam diameter until the beam diameter reaches the target value. Of course, in addition to beam diameter feedback, a position sensor can also be used to feedback the position of the optical lens. For example, using a high-precision position sensor such as a linear variable differential transformer (LVDT) or a magnetic scale, the position measurement accuracy can reach the micron level. These position feedback information can help the host computer 50 control the movement of the voice coil motor more accurately, ensure that the optical lens moves to the correct position, and thus indirectly ensure the accuracy of the beam diameter adjustment.

[0050] In addition, in some optional embodiments, in order to further improve the adjustment accuracy of the voice coil motor for the beam diameter, the linearity of the voice coil motor can be optimized. Specifically, by accurately designing the structural parameters of the motor, such as the length and diameter of the coil, and the distribution of the magnetic field, the output force of the motor and the input current can show a good linear relationship. For example, during the design stage of the voice coil motor, the finite element analysis (FEA) software is used to simulate and analyze the magnetic field distribution and force-current characteristics of the motor, and the geometric parameters of the motor are adjusted to control the force-current linearity error at a low level, such as less than 1%. It is also possible High-precision current sensors and feedback control algorithms are used to precisely control the current through the voice coil motor coil. For example, a high-precision Hall effect current sensor with a measurement accuracy of ±0.1% is used, combined with a precision current feedback control loop such as a proportional-integral-differential (PID) controller to monitor and adjust the current in real time to ensure that the motor's driving force precisely meets the requirements.

[0051] In some preferred embodiments, the beam diameter is controlled by constructing a beam diameter prediction model. Specifically, an initial model is first established for the voice coil motor and its controlled system (including lens movement and beam diameter adjustment). The initial model can be a dynamic model and can be derived based on physical laws. For example, for a motion system in which a voice coil motor drives a lens, a basic model of motor motion can be established based on Newton's second law F=ma (where F is the driving force of the voice coil motor, m is the total mass of the moving parts, and a is the acceleration) and the electromagnetic force equation of the voice coil motor F=BIL (where B is the magnetic field intensity, I is the current, and L is the effective length of the coil). For the relationship between the beam diameter and the position of the optical lens, a corresponding model can be established based on the principles of geometric optics to describe the relationship between the beam diameter and the change in lens position.

[0052] Next, the prediction time domain and the control time domain are defined. In the constructed beam diameter prediction model, the prediction time domain N needs to be determined. p and control time domain N c . Prediction time domain N p Refers to the time range for predicting future output, controlling the time domain N c It refers to the time range within which the control variable (such as the current of the voice coil motor) can be changed. For example, for the voice coil motor to adjust the beam diameter, the prediction time domain can be set to N p = 10 sampling periods, each sampling period is 1 millisecond, that is, predicting the change of beam diameter in the next 10 milliseconds; controlling the time domain N c Can be set to N c= 3 sampling periods, which means that in the next 10 milliseconds, the control variable (motor current) can be changed in the first 3 milliseconds to affect the system output.

[0053] Then, a prediction equation is constructed. Based on the established initial model and the defined prediction time domain, a prediction equation is constructed. The prediction equation is used to calculate the future output of the system given the current state and future control sequence. This embodiment takes a linear discrete system as an example and establishes the following prediction equation: ; Where y represents the output of the beam diameter prediction model, i.e., the beam diameter; μ represents the input of the beam diameter prediction model, such as the motor current; k represents the current moment; i represents the prediction step; j represents the jth moment; n and m represent the number of coefficients related to the beam diameter prediction model, respectively; a ij and b ij denote the coefficients of the beam diameter prediction model, respectively).

[0054] Furthermore, the prediction equation of the beam diameter prediction model is optimized. When optimizing, the optimization goal must be clarified first. For the voice coil motor to adjust the beam diameter, the main goal is to make the beam diameter reach the target value quickly and accurately, and to minimize the overshoot and fluctuation during the adjustment process. For example, the goal can be to adjust the beam diameter from the initial value to the target value in the shortest time, while limiting the maximum overshoot of the beam diameter to no more than a certain proportion. Therefore, the objective function of the optimization set in this embodiment is as follows: ; Where J represents the objective function, r represents the desired beam diameter, Represents the weight coefficient, which is used to balance the importance of control input and output tracking. The above objective function takes into account both the deviation between the system output and the target output and the size of the control input. By adjusting the weight coefficient, a trade-off can be made between control accuracy and control energy.

[0055] Thus, an optimized and updated beam diameter prediction model can be obtained, and in subsequent beam adjustment applications, the beam diameter prediction model can be used to quickly and accurately adjust the beam diameter. For example, the current state of the system can be obtained through sensors, such as the current position of the lens driven by the voice coil motor through a position sensor, and the current beam diameter can be obtained through a beam diameter sensor. This information is then used as the initial condition input of the prediction model, and the prediction model outputs the predicted beam diameter, thereby controlling the rapid adjustment of the voice coil motor.

[0056] The various embodiments in the specification are described in a progressive manner, and each embodiment focuses on the differences from other embodiments. The same and similar parts between the various embodiments can be referred to each other. For the system disclosed in the embodiment, since it corresponds to the method disclosed in the embodiment, the description is relatively simple, and the relevant parts can be referred to the method part description. It should be pointed out that for ordinary technicians in this technical field, without departing from the principles of this application, several improvements and modifications can be made to the present application, and these improvements and modifications also fall within the scope of protection of the claims of this application.

[0057] It should also be noted that, in this specification, relational terms such as first and second, etc. are only used to distinguish one entity or operation from another entity or operation, and do not necessarily require or imply any such actual relationship or order between these entities or operations. Moreover, the terms "comprises", "comprising" or any other variants thereof are intended to cover non-exclusive inclusion, so that a process, method, article or device including a series of elements includes not only those elements, but also other elements not explicitly listed, or also includes elements inherent to such process, method, article or device. In the absence of further restrictions, an element defined by the statement "comprising a ..." does not exclude the presence of other identical elements in the process, method, article or device including the element.

Claims

1. A galvanometer system, characterized in that: include: A laser generating device, used for emitting a laser beam; A beam adjustment module, used for receiving the laser beam and adjusting the beam diameter of the laser beam; A galvanometer module, used for receiving the laser beam and adjusting the beam position of the laser beam; An F-theta mirror is used to receive the laser beam whose beam diameter and beam position are adjusted, and focus the laser beam into a light spot; A host computer, wherein the host computer is provided with a multi-axis galvanometer motion control card, and the multi-axis galvanometer motion control card is respectively connected to the beam adjustment module and the galvanometer module for communication; The host computer is used to receive beam adjustment instructions and input the beam adjustment instructions into the multi-axis galvanometer motion control card, so that the multi-axis galvanometer motion control card sends corresponding beam adjustment instructions to the beam adjustment module and the galvanometer module at the same time.

2. The galvanometer system according to claim 1, characterized in that: One end of the beam adjustment module is connected to the laser generating device, and the other end is connected to one end of the galvanometer module, and the other end of the galvanometer module is connected to the F-theta mirror.

3. The galvanometer system according to claim 1, characterized in that: The beam adjustment module and the galvanometer module both include a plurality of signal pins or interfaces of different types.

4. The galvanometer system according to claim 3, characterized in that: The multi-axis galvanometer motion control card is provided with a plurality of main control chips, and each of the main control chips is respectively connected to a pin signal communication of the beam adjustment module and the galvanometer module.

5. The galvanometer system according to claim 1, characterized in that: The multi-axis galvanometer motion control card is respectively connected to the beam adjustment module and the galvanometer module in communication via the same communication protocol.

6. The galvanometer system according to claim 5, characterized in that: The communication protocol is the XY2-100 protocol or the SL2-100 protocol.

7. The galvanometer system according to claim 1, characterized in that: The beam adjustment module includes a plurality of voice coil motors, and each of the voice coil motors is configured with an optical lens.

8. The galvanometer system according to claim 7, characterized in that: The optical lenses configured for the plurality of voice coil motors are arranged in a line along a light beam propagation direction.

9. A beam adjustment method, applied to the galvanometer system according to any one of claims 1 to 8, characterized in that: The method comprises: The host computer receives the beam adjustment instruction and inputs the beam adjustment instruction into the multi-axis galvanometer motion control card; The multi-axis galvanometer motion control card simultaneously sends corresponding beam adjustment instructions to the beam adjustment module and the galvanometer module; The beam adjustment module and the galvanometer module adjust the laser beam accordingly according to the beam adjustment instructions received respectively.

10. The light beam adjustment method according to claim 9, characterized in that: The multi-axis galvanometer motion control card simultaneously sends corresponding beam adjustment instructions to the beam adjustment module and the galvanometer module, including: The multi-axis galvanometer motion control card sends corresponding beam adjustment instructions to the beam adjustment module and the galvanometer module simultaneously based on the same communication protocol.

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