A galvanometer system and a beam adjustment method

Abstract

The present invention discloses a galvanometer system and a beam adjustment method. The galvanometer system includes: a laser generating device for emitting a laser beam; a beam adjustment module for adjusting the beam diameter of the laser beam; a galvanometer module for adjusting the beam position of the laser beam; an F-theta lens for focusing the laser beam into a light spot; and a host computer provided with a multi-axis galvanometer motion control card, the multi-axis galvanometer motion control card being communicatively connected to the beam adjustment module and the galvanometer module. The host computer is used to receive a beam adjustment instruction and input it into the multi-axis galvanometer motion control card, so that the multi-axis galvanometer motion control card simultaneously sends instructions to the beam adjustment module and the galvanometer module. The present invention simultaneously sends instructions to the beam adjustment module and the galvanometer module through the multi-axis galvanometer motion control card to perform corresponding adjustments on the laser beam, thereby not only solving the delay problem in the galvanometer system, but also improving the processing accuracy of the galvanometer system.

Description

Technical Field

[0001] The present invention relates to the field of optical technologies, and particularly to a galvanometer system and a beam adjustment method. Background Art

[0002] During the laser processing, the size of the laser focused spot determines the processing accuracy and energy density. The energy density and the laser power satisfy:

[0003] ;

[0004] In the above formula, F is the energy density, P avg is the average laser power, r 0 is the radius of the focused spot, f fre is the laser frequency. If it is a continuous laser, this value is 1. Here, when the spot of the focused laser is smaller, the influence range within a single point is smaller, indicating higher processing accuracy and greater energy density. On the contrary, when the focused spot is larger, the influence range is larger, indicating smaller energy density. Therefore, the size of the focused spot can be changed according to different processing materials and processing requirements to meet different processing technology requirements.

[0005] As Figure 1 shown, the existing laser galvanometer system sequentially includes a parallel beam size adjustment module 1, a galvanometer 2, and a focusing lens 3 along the optical path propagation direction. After the laser exits, 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 of the incident laser parallel beam. For example, the larger the radius of the laser beam before entering the focusing lens 3, the smaller the radius of the focused spot obtained by focusing through the focusing lens. Specifically, the parallel beam size adjustment module 1 includes a variable magnification beam expander group, and the variable magnification beam expander group includes multiple lenses. The diameter of the laser beam can be adjusted by adjusting the distance between different lenses.

[0006] The methods for adjusting the spacing between different lenses mainly include manual adjustment and ordinary electric control. However, both of these methods have certain defects. For example, the method of manual adjustment has the defects of low precision and slow response, and cannot meet the requirements of high-precision and fast processing. Another example is that although the method of ordinary electric control has higher precision and response speed than the method of manual adjustment, it still does not meet the requirements of the high-speed galvanometer processing system. In particular, the type of motor and the control method used will greatly limit the precision and response speed of galvanometer processing. And in terms of the type of motor, most of the motors currently used are stepper motors or motors, and their precision cannot meet the high-standard requirements. In addition, in terms of the control method, the protocols for controlling the movement of the motor and the galvanometer are often two or more protocols, which will cause different control delays between the parallel beam size adjustment module and the galvanometer. Different control delays will result in insufficient precision and reliability of the final processing result, and will also increase the complexity of the overall galvanometer processing system, reduce the response speed, and increase the difficulty of subsequent calibration.

[0007] This delay between the galvanometer and the beam expander response will lead to a reduction in the processing precision of the entire processing system. Therefore, designing a system that can achieve synchronous response between 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

[0008] Embodiments of the present invention provide a galvanometer system and a beam adjustment method, aiming to achieve synchronous response of the galvanometer system and improve the processing precision of the galvanometer system.

[0009] Embodiments of the present invention provide a galvanometer system, including:

[0010] A laser generating device for emitting a laser beam;

[0011] A beam adjustment module for receiving the laser beam and adjusting the beam diameter of the laser beam;

[0012] A galvanometer module for receiving the laser beam and adjusting the beam position of the laser beam;

[0013] An F-theta lens for receiving the laser beam whose beam diameter and beam position have been adjusted and focusing the laser beam into a light spot;

[0014] An upper computer, the upper computer is provided with a multi-axis galvanometer motion control card, and the multi-axis galvanometer motion control card is respectively communicatively connected with the beam adjustment module and the galvanometer module;

[0015] Among them, 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 simultaneously sends corresponding beam adjustment instructions to the beam adjustment module and the galvanometer module.

[0016] Further, one end of the beam adjustment module is connected to the laser generating device, 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 lens.

[0017] Further, both the beam adjustment module and the galvanometer module include multiple signal pins or interfaces of different types.

[0018] Further, the multi-axis galvanometer motion control card is provided with multiple main control chips, and each main control chip is respectively communicatively connected to a kind of pin signal in the beam adjustment module and the galvanometer module.

[0019] Further, the multi-axis galvanometer motion control card is communicatively connected to the beam adjustment module and the galvanometer module respectively through the same communication protocol.

[0020] Further, the communication protocol is the XY2-100 protocol or the SL2-100 protocol.

[0021] Further, the beam adjustment module includes multiple voice coil motors, and each voice coil motor is configured with an optical lens.

[0022] Further, the optical lenses configured by the multiple voice coil motors are arranged in a line along the beam propagation direction.

[0023] An embodiment of the present invention also provides a beam adjustment method, which is applied to the galvanometer system described in any one of the above, and the method includes:

[0024] The host computer receives a beam adjustment instruction and inputs the beam adjustment instruction into the multi-axis galvanometer motion control card;

[0025] The multi-axis galvanometer motion control card simultaneously sends corresponding beam adjustment instructions to the beam adjustment module and the galvanometer module;

[0026] The beam adjustment module and the galvanometer module perform corresponding adjustments on the laser beam according to the received beam adjustment instructions respectively.

[0027] The multi-axis galvanometer motion control card simultaneously sending corresponding beam adjustment instructions to the beam adjustment module and the galvanometer module includes:

[0028] The multi-axis galvanometer motion control card simultaneously sends corresponding beam adjustment instructions to the beam adjustment module and the galvanometer module based on the same set of communication protocols.

[0029] An embodiment of the present invention provides a galvanometer system and a beam adjustment method. The galvanometer system includes: a laser generating device for emitting a laser beam; a beam adjustment module for receiving the laser beam and adjusting the beam diameter of the laser beam; a galvanometer module for receiving the laser beam and adjusting the beam position of the laser beam; an F-theta lens for receiving the laser beam whose beam diameter and beam position have been adjusted and focusing the laser beam into a light spot; a host computer, the host computer is provided with a multi-axis galvanometer motion control card, and the multi-axis galvanometer motion control card is respectively communicatively connected with the beam adjustment module and the galvanometer module; wherein, the host computer is used for receiving a beam adjustment instruction and inputting the beam adjustment instruction into the multi-axis galvanometer motion control card, so that the multi-axis galvanometer motion control card simultaneously sends corresponding beam adjustment instructions to the beam adjustment module and the galvanometer module. By the multi-axis galvanometer motion control card in the host computer in the embodiment of the present invention, beam adjustment instructions are simultaneously sent to the beam adjustment module and the galvanometer module to achieve synchronous response of the galvanometer system, and the beam adjustment module and the galvanometer module can adjust the laser beam according to the beam adjustment instructions, so that the light spot finally focused by the F-theta lens meets the requirements of the beam adjustment instructions. In this way, not only the delay problem in the galvanometer system is solved, the overall processing coordination of the galvanometer system is enhanced, but also the processing accuracy of the galvanometer system is improved. Description of the Drawings

[0030] In order to more clearly illustrate the technical solutions of the embodiments of the present invention, the drawings required for the description of the embodiments will be briefly introduced below. Obviously, the drawings in the following description are some embodiments of the present invention. For those of ordinary skill in the art, other drawings can be obtained based on these drawings without creative efforts.

[0031] Figure 1 It is a schematic structural diagram of a laser galvanometer system in the prior art;

[0032] Figure 2 It is a schematic structural diagram of a galvanometer system provided by an embodiment of the present invention;

[0033] Figure 3 It is another schematic structural diagram of a galvanometer system provided by an embodiment of the present invention;

[0034] Figure 4 It is a schematic flow diagram of a beam adjustment method provided by an embodiment of the present invention. Detailed Embodiments

[0035] Next, in combination with the accompanying drawings in the embodiments of the present invention, the technical solutions in the embodiments of the present invention will be clearly and completely described. Obviously, the described embodiments are part of the embodiments of the present invention, rather than all the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by those of ordinary skill in the art without creative efforts shall fall within the protection scope of the present invention.

[0036] It should be understood that when used in this specification and the appended claims, the terms "comprises" and "comprising" indicate the presence of the described features, wholes, steps, operations, elements, and / or components, but do not preclude the presence or addition of one or more other features, wholes, steps, operations, elements, components, and / or their combinations.

[0037] 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 this 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 the plural forms.

[0038] It should be further understood that the term "and / or" used in this specification of the present invention and the appended claims refers to any combination and all possible combinations of one or more of the associated listed items, and includes these combinations.

[0039] Please refer to the following Figure 2 , the embodiments of the present invention provide a galvanometer system, and the galvanometer system includes:

[0040] A laser generating device 10 for emitting a laser beam;

[0041] A beam adjusting module 20 for receiving the laser beam and adjusting the beam diameter of the laser beam;

[0042] A galvanometer module 30 for receiving the laser beam and adjusting the beam position of the laser beam;

[0043] An F-theta lens 40 for receiving the laser beam whose beam diameter and beam position have been adjusted and focusing the laser beam into a light spot;

[0044] An upper computer 50, the upper computer 50 is provided with a multi-axis galvanometer motion control card 501, and the multi-axis galvanometer motion control card 501 is respectively communicatively connected with the beam adjusting module 20 and the galvanometer module 30;

[0045] Among them, the host computer 50 is used to receive a beam adjustment instruction and input the beam adjustment instruction into the multi-axis galvanometer motion control card 501, so that 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.

[0046] In this embodiment, the galvanometer system includes a laser generating device 10, a beam adjustment module 20, a galvanometer module 30, an F-theta lens 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. 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 received beam adjustment instructions, so that the laser beam finally incident on the F-theta lens 40 can be focused by the F-theta lens 40 into a spot that meets the requirements.

[0047] 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 the synchronous response of the galvanometer system, and enables the beam adjustment module 20 and the galvanometer module 30 to adjust the laser beam according to the beam adjustment instructions, so that the spot finally focused by the F-theta lens 40 meets the requirements of the beam adjustment instructions. In this way, not only the delay problem in the galvanometer system is solved, the overall processing coordination of the galvanometer system is enhanced, but also the processing accuracy of the galvanometer system is improved. Moreover, 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 doubled compared with the prior art.

[0048] In one embodiment, as Figure 3 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. The other end of the galvanometer module 30 is connected to the F-theta lens 40.

[0049] In this embodiment, the laser generating device 10, the beam adjusting module 20, the galvanometer module 30, and the F-theta lens 40 are sequentially connected along the optical path propagation direction. Among them, the beam adjusting 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 divergence angle. After the preliminary adjustment of the beam adjusting module 20, the parameters of the laser beam are optimized, laying a foundation for 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 command, 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 lens 40. The F-theta lens 40, as the final optical element, functions to focus the adjusted laser beam and generate a 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.

[0050] In one embodiment, both the beam adjusting module 20 and the galvanometer module 30 include multiple types of signal pins or interfaces with different types.

[0051] Correspondingly, the multi-axis galvanometer motion control card 501 is provided with multiple main control chips, and each main control chip is respectively communicatively connected to one type of pin signal in the beam adjusting module 20 and the galvanometer module 30.

[0052] In this embodiment, by respectively providing multiple types of signal pins or interfaces on the beam adjusting 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 type of signal pin. For example, the multi-axis galvanometer motion control is provided with 3 main control chips. The first main control chip is connected to the clock signal pins in the beam adjusting module 20 and the galvanometer module 30 for unified timing control of the beam adjusting module 20 and the galvanometer module 30. The second main control chip is connected to the serial digital signal interfaces in the beam adjusting module 20 and the galvanometer module 30 for transmitting corresponding beam adjustment commands, etc., to the beam adjusting module 20 and the galvanometer module 30. The second main control chip is connected to the chip select signal pins in the beam adjusting module 20 and the galvanometer module 30 for selecting to connect or disconnect from the beam adjusting module 20 and / or the galvanometer module 30.

[0053] In another embodiment, the multi-axis galvanometer motion control card 501 is communicatively connected to the beam adjusting module 20 and the galvanometer module 30 respectively through the same communication protocol.

[0054] Specifically, the communication protocol is the XY2-100 protocol or the SL2-100 protocol.

[0055] 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.

[0056] 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.

[0057] 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.

[0058] 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.

[0059] It should be clear that in the prior art, a galvanometer motion control card controlled by a galvanometer protocol usually corresponds to only 1 or 2 galvanometer axes. However, 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 simultaneously (for example, the x-galvanometer axis and y-galvanometer axis of the galvanometer module 30, as well as 3 voice coil motors in the optical adjustment module, etc. In this way, the multi-axis galvanometer motion control card 501 described in this embodiment can achieve the effect of simultaneously controlling 5 galvanometer axes). It can be understood that after setting 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 all participate in the operation, thereby improving the control effect. Further, the control delay of multiple galvanometer axes controlled by the multi-axis galvanometer motion control card 501 can be made to meet the preset requirements, such as less than 10 us, by continuously optimizing the control card hardware and the supporting underlying program, which can further improve the response speed of the galvanometer system. When optimizing, functional modules can be first written and tested on the multi-axis galvanometer motion control card 501, and then the objects to be optimized can be determined based on the test results, such as replacing with more precise electronic components. At the same time, the signal instruction allocation of the multi-axis galvanometer motion control card 501 can also be optimized iteratively to improve the response speed and accuracy of the system. It should also be noted that the galvanometer motion control cards in the prior art usually need to adopt 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 in

[0060] For example, in the 3D metal printing industry of shoe molds, for the sole molds, there are usually many fine patterns or lines, as well as very flat surfaces. For the fine patterns and lines, a smaller laser focusing spot is required for processing, while for the large flat surfaces, a larger laser focusing spot can be used for processing. In this regard, the existing 2D galvanometers can only use small focusing spots for processing, which results in a very low overall processing efficiency. When processing through the galvanometer system provided by this embodiment, the three-dimensional model of the sole mold can be first obtained by the host computer 50, and the three-dimensional model can be automatically sliced to identify and divide the patterns, lines, planes, etc. therein. Then, corresponding beam adjustment instructions can be generated according to the identification and division results. For example, a beam adjustment instruction with a smaller beam diameter is generated for the patterns and lines, and a beam adjustment instruction with a larger beam diameter is generated for the plane, so as to realize the variable focusing spot function of the galvanometer system, thereby improving the processing efficiency of the galvanometer system.

[0061] Figure 4 FIG. is a schematic flowchart of a beam adjustment method provided by an embodiment of the present invention. This method is applied to the galvanometer system as described above, and the method specifically includes: steps S101 to S103.

[0062] 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;

[0063] Step S102, 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;

[0064] Step S103, the beam adjustment module 20 and the galvanometer module 30 perform corresponding adjustments on the laser beam according to the beam adjustment instructions received by each of them.

[0065] 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 the synchronous response of the galvanometer system, and enables the beam adjustment module 20 and the galvanometer module 30 to perform corresponding adjustments on the laser beam according to the beam adjustment instructions, so that the spot finally focused by the F-theta lens 40 meets the requirements of the beam adjustment instructions. In this way, not only the delay problem in the galvanometer system is solved, the overall processing coordination of the galvanometer system is enhanced, but also the processing accuracy of the galvanometer system is improved.

[0066] 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:

[0067] The multi-axis galvanometer motion control card 501 sends corresponding beam adjustment commands to the beam adjustment module 20 and the galvanometer module 30 simultaneously based on the same communication protocol.

[0068] Based on the multi-axis galvanometer motion control card 501, the effects of simultaneously controlling the beam adjustment module 20 and the galvanometer module 30 can be achieved through a set of communication protocols (such as the XY2-100 protocol or the SL2-100 protocol). In this way, the problem of time delay in the beam adjustment module 20 and the galvanometer module 30 can be avoided, and further, the problem of reduced processing accuracy caused by the incoordination of the entire processing system due to the incoordination of work can be prevented.

[0069] In some alternative embodiments, the host computer 50 is further configured with a user interaction interface through which a user can intuitively input beam adjustment commands, such as specifying parameters such as the size, position, or shape of the light spot. After receiving these commands, the host computer 50 will immediately process them and convert them into signals recognizable 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 simultaneously. During the whole process, the coordinated work among 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, this galvanometer system also has a high degree of flexibility and scalability and can be customized and optimized according to actual application requirements to meet the processing requirements in different fields.

[0070] For example, the host computer 50 can receive voice commands input by the user, and perform voice recognition on the voice commands through a voice recognition module or software using corresponding voice recognition algorithms (such as a voice recognition model based on deep learning, etc.) to obtain the corresponding text content. Then, natural language processing (NLP) technology is used to extract features from the text content. For example, key nouns (such as light spot, light beam, etc.), verbs (such as adjust, change, etc.), and determiners (such as size, position, etc.) are extracted through lexical analysis to construct appropriate feature vectors or syntactic trees and other structures to accurately identify the instruction content regarding light spot adjustment. After obtaining the light beam adjustment instruction, it is necessary to further parse the instruction, and based on the semantic information, keywords, etc. contained in the instruction, distinguish which part is for light beam diameter adjustment and which part is related to light beam position adjustment. For example, if expressions such as "increase the diameter of the light spot" or "reduce the thickness of the light beam" appear in the text, they can be classified as light beam diameter adjustment instructions; while content such as "move the light spot to the left" or "adjust the position of the light beam to above" can be classified into light beam position adjustment instructions. Thus, the light beam diameter adjustment instruction and the light beam position adjustment instruction are divided. And the light beam diameter adjustment instruction and the light beam position adjustment instruction are respectively sent to the light beam adjustment module and the galvanometer module. For example, the instruction received by the host computer 50 is "move the light beam to the coordinates (x = 10, y = 20)" or "translate the light beam 5 units to the left and 3 units upward", etc. 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 displacement amounts in the horizontal and vertical directions (-5 and 3, where it can be considered that the left direction is negative and the upward direction is positive).

[0071] In addition, after focusing the light spot through the F-theta lens 40, the host computer 50 can collect relevant information of the light spot through image recognition or other means, such as the actual size and position of the light spot, and then optimize and feedback the processing program of the light beam adjustment instruction according to the actual information of the light spot to make the subsequent generated light beam adjustment instruction more accurate and reliable.

[0072] In an actual application scenario, the beam adjustment module 20 includes a plurality of voice coil motors, and each voice coil motor is configured with an optical lens. Specifically, the optical lenses configured by the plurality of voice coil motors are arranged in a line along the beam propagation direction. When using the voice coil motor to adjust the beam diameter, in order to ensure the adjustment accuracy and improve the overall processing accuracy of the galvanometer system, the voice coil motor is pre-initialized and calibrated. For example, the zero position of the voice coil motor is determined (i.e., the optical lens is in a certain initial position, and the beam diameter corresponding to this position can be used as a reference value), and parameters of the drive circuit of the voice coil motor are set, such as current limit, speed control and other parameters, to ensure that the voice coil motor can operate smoothly and accurately. Secondly, when receiving the beam adjustment instruction sent by the multi-axis galvanometer motion control card 501, it can be understood that this beam adjustment instruction is usually a voltage control signal for the voice coil motor, and its magnitude and polarity determine the magnitude and direction of the current in the voice coil motor. For example, if it is necessary to move the optical lens closer to the light source to reduce the beam diameter, the voltage control signal will cause current to pass through the coil of the voice coil motor, generating a force pointing in the direction of the light source. Subsequently, under the action of the force, the mover of the voice coil motor drives the lens to move along the optical axis direction. 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 generated force will be greater, and the lens movement speed will be faster; conversely, the optical lens movement speed will be slower.

[0073] Furthermore, in order to achieve more precise 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 is fed back to the host computer 50. The host computer 50 will continuously adjust the control signal sent to the drive circuit of the voice coil motor according to the difference between the set target beam diameter and the actually 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, high-precision position sensors such as linear variable differential transformers (LVDTs) or magnetic scale rulers are used, and their position measurement accuracy can reach the micron level. These position feedback information can help the host computer 50 more precisely control the movement of the voice coil motor, ensure that the optical lens moves to the accurate position, and thus indirectly ensure the accuracy of beam diameter adjustment.

[0074] In addition, in some alternative embodiments, to further provide the adjustment accuracy of the voice coil motor for the beam diameter, the linearity of the voice coil motor can be optimized. Specifically, by precisely designing the structural parameters of the motor, such as the length and diameter of the coil, and the distribution of the magnetic field, etc., a good linear relationship can be presented between the output force of the motor and the input current. For example, in 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%, etc. It is also possible to

[0075] adopt a high-precision current sensor and a feedback control algorithm to precisely control the current passing through the voice coil motor coil. For example, a high-precision Hall effect current sensor is used, and its measurement accuracy can reach ±0.1%, and combined with a precise current feedback control loop, such as a proportional-integral-derivative (PID) controller, to monitor and adjust the current in real time to ensure that the driving force of the motor precisely meets the requirements.

[0076] In some preferred embodiments, the beam diameter is regulated by constructing a beam diameter prediction model. Specifically, first, an initial model is established for the voice coil motor and the system it controls (including lens movement and beam diameter adjustment). This initial model can be a dynamic model and can be derived based on physical laws. For example, for the motion system of the voice coil motor driving the lens, according to 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), combined with the electromagnetic force equation of the voice coil motor F = BIL (where B is the magnetic field strength, I is the current, and L is the effective length of the coil), a basic model of the motor motion can be established. For the relationship between the beam diameter and the position of the optical lens, a corresponding model can be established according to the principles of geometric optics to describe the relationship between the beam diameter and the change of the lens position.

[0077] Next, the prediction horizon and the control horizon are defined. In the constructed beam diameter prediction model, it is necessary to determine the prediction horizon N p and the control horizon N c . The prediction horizon N p refers to the time range for predicting future outputs, and the control horizon N c refers to the time range within which the control variables (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 horizon can be set as N p = 10 sampling periods, and each sampling period is 1 millisecond, that is, predicting the change of the beam diameter within the next 10 milliseconds; the control horizon N c can be set as N c= 3 sampling periods, which means that within the next 10 milliseconds, the control variable (motor current) can be changed in the first 3 milliseconds to affect the system output.

[0078] Subsequently, a prediction equation is constructed. Based on the established initial model and the defined prediction horizon, 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. In this embodiment, taking a linear discrete system as an example, the following prediction equation is established:

[0079] ;

[0080] 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 motor current, etc.; k represents the current moment; i represents the prediction step; j represents the j-th moment; n and m respectively represent the number of coefficients related to the beam diameter prediction model; a ij and b ij respectively represent the coefficients of the beam diameter prediction model).

[0081] Furthermore, the prediction equation of the beam diameter prediction model is optimized. When optimizing, the optimization objective must be clarified first. For adjusting the beam diameter by a voice coil motor, the main objective is to make the beam diameter reach the target value quickly and accurately, and minimize the overshoot and fluctuation during the adjustment process. For example, the objective can be to adjust the beam diameter from the initial value to the target value in the shortest time, while restricting the maximum overshoot of the beam diameter not to exceed a certain proportion. Therefore, this embodiment sets the following objective function for optimization:

[0082] ;

[0083] 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 magnitude of the control input, and can trade off between control accuracy and control energy by adjusting the weight coefficient.

[0084] Thus, an optimized and updated beam diameter prediction model can be obtained. Then, in subsequent beam adjustment applications, the beam diameter can be adjusted quickly and accurately through the beam diameter prediction model. For example, the current state of the system can be obtained through sensors, such as the current position of the voice coil motor driving the lens through a position sensor and the current beam diameter through a beam diameter sensor, and then this information is input as the initial conditions of the prediction model, and the prediction model outputs the predicted beam diameter, thereby controlling the voice coil motor to adjust quickly.

[0085] The various embodiments in the specification are described in a progressive manner. Each embodiment focuses on the differences from other embodiments, and the same or similar parts among the 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 description in the method section. It should be noted that for those of ordinary skill in the art in this technical field, without departing from the principle of this application, several improvements and modifications can be made to this application, and these improvements and modifications also fall within the protection scope of the claims of this application.

[0086] It should also be noted that in this specification, relational terms such as first and second are only used to distinguish one entity or operation from another entity or operation, and do not necessarily require or imply any actual relationship or order between these entities or operations. Moreover, the term "comprising", "including" or any other variant thereof is intended to cover non-exclusive inclusion, so that a process, method, article or device comprising a series of elements not only includes those elements, but also includes other elements not expressly listed, or elements inherent to such process, method, article or device. Without further limitation, an element defined by the statement "comprising an..." does not exclude the existence of another identical element in the process, method, article or device comprising 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; The beam adjustment module includes a plurality of voice coil motors, and each of the voice coil motors is equipped with an optical lens; A galvanometer module, used for receiving the laser beam and adjusting the beam position of the laser beam; the beam adjustment module and the galvanometer module both include a plurality of signal pins or interfaces of different types, including a clock signal pin; 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 multi-axis galvanometer motion control card is respectively connected to the beam adjustment module and the galvanometer module for communication through the same communication protocol; 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 in the beam adjustment module and the galvanometer module; one of the main control chips is connected to the clock signal pins in the beam adjustment module and the galvanometer module for unified timing control of the beam adjustment module and the galvanometer module; The host computer is used to receive the 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 beam adjustment module outputs the beam diameter to be adjusted through the beam diameter prediction model according to the following formula: ； 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; 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 They represent the coefficients of the beam diameter prediction model respectively.

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 communication protocol is the XY2-100 protocol or the SL2-100 protocol.

4. The galvanometer system according to claim 1, 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.

5. A beam adjustment method, applied to the galvanometer system according to any one of claims 1 to 4, 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.

6. The light beam adjustment method according to claim 5, 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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