A magnetic field focusing correction electron beam acceleration system and method

Abstract

This invention discloses a magnetic field focusing and corrected electron beam acceleration system, comprising: an electron gun using a nanocomposite cathode material with optimized structure for controlled emission; a multi-stage accelerating tube with adjustable resonant frequency and a collimation device; a focusing coil with superconducting winding, providing a superior magnetic field with adjustable intensity; a correction coil with three-dimensional, independently controlled sub-coils; and a control system including sensors, etc., based on machine learning intelligent control to achieve electron beam focusing and correction. The collaborative work of all components ensures the electron beam maintains a good state during acceleration, meeting the needs of various application scenarios, such as electron microscopy and electron beam lithography, which require high-precision electron beam control. This invention achieves high-precision electron beam control, efficient and stable acceleration, accurate focusing and correction, intelligent adaptive control system, improved beam quality, and ensures continuous optimization and reliable operation of system performance, promoting development in multiple fields.

Description

Technical Field

[0001] This invention relates to the field of electron beam acceleration system technology, and in particular to a magnetic field focusing correction electron beam acceleration system and method. Background Technology

[0002] In the field of modern science and technology, electron beam acceleration technology is widely used in many areas, such as electron microscopy, electron beam lithography, radiation therapy, and material modification. With the continuous development of these applications, the performance requirements for electron beams are increasing, especially in terms of energy stability, focusing accuracy, and beam quality.

[0003] In electron microscopy, high-resolution imaging relies on a highly focused and energy-stable electron beam to clearly distinguish microscopic structures. Electron beam lithography, on the other hand, requires the electron beam to have precise focusing and positioning capabilities to achieve nanometer-level processing precision, which is crucial for high-tech industries such as semiconductor chip manufacturing. In the field of radiation therapy, a precisely focused electron beam can accurately deliver radiation energy to diseased tissues while minimizing damage to surrounding healthy tissues.

[0004] However, traditional electron beam acceleration systems face numerous challenges in practical applications. On the one hand, the initial characteristics of the electron beam emitted by the electron gun are difficult to control precisely, such as the emission angle and initial divergence, which affects subsequent acceleration and focusing effects. On the other hand, the performance optimization of the microwave resonant cavity during acceleration is limited, resulting in low electron beam acceleration efficiency and poor energy stability.

[0005] The magnetic field uniformity and adjustment precision generated by the focusing coil are insufficient to meet the increasingly demanding focusing requirements, easily causing defocusing of the electron beam during transmission and affecting beam quality. The design of the correction coil is not flexible and precise enough to effectively cope with the dynamic changes of the electron beam during acceleration, and it cannot correct in real time the problem of the electron beam deviating from the ideal trajectory caused by various factors (such as space charge effect, relativistic effect, etc.).

[0006] Furthermore, traditional control systems lack the ability to accurately predict and adaptively adjust electron beam behavior, often resorting to relatively fixed control strategies that are ill-suited to different application scenarios and complex, ever-changing electron beam conditions. This prevents the system from effectively and promptly adjusting the electron beam focusing and acceleration process in the face of various disturbances, thus limiting the overall performance improvement of the electron beam acceleration system.

[0007] Therefore, there is an urgent need for an innovative magnetic field focusing and corrected electron beam acceleration system and method that can overcome the shortcomings of existing technologies, achieve more precise control and optimization of the electron beam, meet the stringent requirements of modern scientific and technological development for electron beam performance, and promote further development in related fields. This invention is proposed against this background, aiming to provide a high-performance, high-reliability electron beam acceleration solution. Summary of the Invention

[0008] This invention proposes a magnetic field focusing correction electron beam acceleration system and method to solve the problems mentioned in the prior art.

[0009] To achieve the above objectives, the present invention employs the following technical solution: a magnetic field focusing and correcting electron beam acceleration system, comprising:

[0010] The electron gun uses a nanocomposite cathode material, and its internal structure has been optimized to precisely control the electron beam emission angle and initial divergence.

[0011] The accelerating tube adopts a multi-stage accelerating structure. Each stage of the accelerating structure consists of a microwave resonant cavity, and its resonant frequency is dynamically adjusted in the range of 5GHz-15GHz. The outer shell of the accelerating tube is made of low-loss, high-thermal-conductivity ceramic material. An electron beam collimation device is provided between the accelerating tube and the electron gun.

[0012] The focusing coil is made of multi-layer high-temperature superconducting tape. The coil has a cooling channel inside and liquid helium cryogenic medium is introduced to achieve efficient cooling. The magnetic field distribution of the focusing coil is optimized through the coil winding layout to generate a uniform focusing magnetic field with continuously adjustable magnetic field strength.

[0013] The correction coil adopts a three-dimensional structure design, consisting of multiple independently controlled sub-coils, which generate a correction magnetic field in three spatial dimensions. The correction coil and the focusing coil are isolated by a magnetic field coupling device to avoid mutual interference.

[0014] The control system includes high-precision sensors, high-speed data acquisition cards, and intelligent controllers. The sensors employ electron beam diagnostic technology to measure the position, energy, divergence, and beam current intensity parameters of the electron beam in real time. The intelligent controller, based on machine learning algorithms and adaptive control strategies, predicts the dynamic change trend of the electron beam through a calculation model based on the real-time acquired data, and controls the magnetic field strength of the focusing coil and the correction coil to achieve focusing and correction of the electron beam.

[0015] Furthermore, the nanocomposite cathode material of the electron gun is synthesized through a preparation process that includes tungsten-based material doped with silicon carbide nanoparticles. The preparation process includes high-temperature sintering and chemical vapor deposition steps, and the high voltage output voltage stability of the electron gun is better than ±0.01%.

[0016] Furthermore, the microwave resonant cavity of the accelerating tube adopts an elliptical cavity and a gradually changing coupling structure design to improve the interaction efficiency between the microwave field and the electron beam. The vacuum system inside the accelerating tube uses a multi-stage vacuum pump group, and the ultimate vacuum degree can reach 1×10⁻ 8 Below Pascal.

[0017] Furthermore, the high-temperature superconducting tape of the focusing coil has high critical current density and low AC loss performance parameters. The coil winding process adopts a non-inductive winding method to improve the magnetic field uniformity. The magnetic field adjustment system of the focusing coil adopts a current source adjustment resolution of 0.1 mA.

[0018] Furthermore, the sub-coils of the correction coil are miniaturized and made of copper-nickel alloy. Each sub-coil is equipped with an independent drive circuit, which uses high-speed switching elements to switch and control the magnetic field strength. A magnetic field shield is provided around the correction coil to reduce external magnetic field interference.

[0019] Furthermore, the intelligent controller of the control system stores an electron beam behavior model and a correction algorithm library, automatically selecting appropriate control strategies according to different application scenarios and electron beam characteristics. At the same time, the controller is connected to external devices through a high-speed communication interface to realize remote monitoring and operation, and records and analyzes system operation data in real time.

[0020] Furthermore, an electron beam acceleration method using magnetic field focusing correction includes the following steps:

[0021] S1. The electron gun emits an electron beam. By controlling the cathode temperature and high voltage power supply parameters of the electron gun, the electron beam has a predetermined initial energy, emissivity and divergence. After passing through the collimation device, the electron beam enters the accelerating tube at a high-precision incident angle.

[0022] S2. The accelerating tube dynamically adjusts the resonant frequency of the microwave resonant cavity and the input microwave power according to the energy requirements of the electron beam to accelerate the electron beam efficiently. During the acceleration process, the vacuum degree and microwave field distribution parameters inside the accelerating tube are monitored in real time.

[0023] S3. The focusing coil calculates the initial focusing magnetic field strength based on the initial parameters of the electron beam and the energy changes during the acceleration phase through the control system, generates a focusing magnetic field to initially focus the electron beam, and continuously monitors the focusing state of the electron beam during the focusing process.

[0024] S4. The sensor monitors the position, energy, and divergence status parameters of the electron beam in real time and transmits the data to the intelligent controller through the data acquisition card.

[0025] S5. The intelligent controller inputs the received real-time data into the pre-trained electron beam behavior prediction model, combines it with the algorithms in the correction algorithm library, calculates the strength and direction of the correction magnetic field, controls the correction coil to generate the correction magnetic field, corrects the focusing of the electron beam, continuously optimizes the control parameters during the correction process to ensure that the electron beam always maintains the best focusing state during acceleration, and dynamically adjusts the microwave parameters of the accelerating tube according to the actual state of the electron beam to achieve coordinated optimization of acceleration and focusing.

[0026] S6. Regularly conduct comprehensive performance evaluations of the system, including the final energy of the electron beam, beam quality, and focusing accuracy. Based on the evaluation results, use machine learning algorithms to automatically optimize and upgrade the models and algorithms in the control system, continuously improving the overall performance of the system. Furthermore, during system operation, use intelligent diagnostic functions to promptly identify potential faults.

[0027] Furthermore, in step S3, the initial focusing magnetic field strength is calculated based on a multiphysics coupling simulation model, considering the space charge effect and relativistic effects of the electron beam. The formula is as follows: Where Bf is the focusing magnetic field strength, E0 is the initial energy of the electron beam, D0 is the spatial distance parameter corresponding to the initial divergence angle of the electron beam, L is the length of the accelerating tube, I is the electron beam current intensity, ε is the electron beam emittance, m0 is the electron rest mass, c is the speed of light in vacuum, and k1 and k2 are coefficients obtained by fitting a large amount of experimental data and simulation results. Furthermore, during the focusing process, an adaptive feedback control algorithm is used to fine-tune the focusing magnetic field strength in real time according to the actual focusing situation of the electron beam. The fine-tuning formula is: Where ΔBf is the adjustment amount of the focusing magnetic field strength, F is the deviation between the actual focusing position and the ideal focusing position of the electron beam, F0 is the preset focusing position deviation threshold, D is the deviation between the actual divergence and the initial divergence of the electron beam, D0 is the preset divergence deviation threshold, and k3 and k4 are adaptive adjustment coefficients.

[0028] Furthermore, in step S5, the calculation of the strength and direction of the correction magnetic field adopts a neural network algorithm based on deep learning. The input layer of the neural network is the real-time state parameters of the electron beam, and the output layer is the strength and direction of the correction magnetic field. The training process uses a large amount of simulation and actual experimental data to ensure the accuracy and generalization ability of the algorithm. The generation of the correction magnetic field adopts pulse modulation technology. According to the dynamic changes of the electron beam, the pulse width, frequency and amplitude of the correction magnetic field are controlled to achieve the correction of the electron beam focusing. In addition, a fuzzy control strategy is introduced during the correction process to handle the uncertainties in the system and improve the stability and robustness of the correction.

[0029] Furthermore, in step S6, the performance evaluation index system includes multiple quantitative indicators such as the energy stability of the electron beam, beam uniformity, and divergence reduction rate, as well as qualitative indicators such as the imaging quality and processing accuracy of the electron beam in practical applications. The system optimization and upgrade process adopts reinforcement learning algorithm to automatically explore and optimize the parameter settings and algorithm strategies of the control system based on the performance evaluation results. At the same time, a fault prediction model is established to predict the possible fault types and times based on big data analysis and machine learning technology.

[0030] Compared with existing technologies, the beneficial effects of this invention are:

[0031] The electron gun of this invention employs a nanocomposite cathode material and an optimized internal structure, enabling precise control of the electron beam emission angle and initial divergence, laying the foundation for subsequent precise acceleration and focusing. For example, in electron beam lithography, it can ensure nanoscale processing accuracy.

[0032] The focusing coil is wound with multi-layer high-temperature superconducting tape, with optimized magnetic field distribution and continuously adjustable intensity. Combined with the three-dimensional structure of the correction coil and the independent control sub-coil, it can achieve precise focusing and correction of the electron beam in three spatial dimensions, so that the electron beam always maintains an ideal state during acceleration and effectively improves the beam quality.

[0033] The multi-stage accelerating structure and dynamically tunable resonant frequency (5GHz - 15GHz) of the accelerating tube, combined with an optimized microwave resonant cavity design (elliptical cavity, gradually changing coupling structure) and a high-vacuum system (ultimate vacuum level up to 1×10⁻⁻⁻⁴), 8 (Below Pascal), this significantly improves the interaction efficiency between the microwave field and the electron beam, achieving efficient acceleration while ensuring electron beam energy stability. For example, in electron microscopy, it can provide a stable high-energy electron beam, improving imaging resolution.

[0034] The high-precision sensors, high-speed data acquisition cards, and intelligent controllers in the control system, based on machine learning algorithms and adaptive control strategies, can monitor and precisely control the magnetic field strength in real time according to the dynamic changes of the electron beam, achieving synergistic optimization of acceleration and focusing. Simultaneously, it can automatically select appropriate control strategies according to different application scenarios and also allows for remote monitoring, improving the system's flexibility and ease of use.

[0035] Regular comprehensive performance evaluations and machine learning-based automatic optimization and upgrade mechanisms continuously improve overall system performance, ensuring long-term stable operation. For example, in radiation therapy, it maintains consistently high-precision electron beam focusing and energy output. Simultaneously, intelligent diagnostic functions can promptly identify potential faults, improving system reliability and reducing maintenance costs. Attached Figure Description

[0036] Figure 1This is a schematic block diagram of a magnetic field focusing and correcting electron beam acceleration system proposed in this invention;

[0037] Figure 2 This is a schematic block diagram of a magnetic field focusing correction electron beam acceleration method proposed in this invention. Detailed Implementation

[0038] The technical solutions of the embodiments of the present invention will be clearly and completely described below with reference to the accompanying drawings. Obviously, the described embodiments are only some embodiments of the present invention, and not all embodiments. Based on the embodiments of the present invention, all other embodiments obtained by those skilled in the art without creative effort are within the scope of protection of the present invention.

[0039] In the description of this invention, it should be understood that the terms "center," "longitudinal," "lateral," "length," "width," "thickness," "upper," "lower," "front," "rear," "left," "right," "vertical," "horizontal," "top," "bottom," "inner," "outer," "clockwise," and "counterclockwise," etc., indicate the orientation or positional relationship based on the orientation or positional relationship shown in the accompanying drawings. They are only for the convenience of describing this invention and simplifying the description, and do not indicate or imply that the device or element referred to must have a specific orientation, or be constructed and operated in a specific orientation. Therefore, they should not be construed as limitations on this invention.

[0040] Furthermore, the terms "first" and "second" are used for descriptive purposes only and should not be construed as indicating or implying relative importance or implicitly specifying the number of indicated technical features. Thus, features defined with "first" and "second" may explicitly or implicitly include one or more of the stated features. In the description of this invention, "a plurality of" means two or more, unless otherwise explicitly specified. Furthermore, the terms "installed," "connected," and "linked" should be interpreted broadly; for example, they may refer to a fixed connection, a detachable connection, or an integral connection; they may refer to a mechanical connection or an electrical connection; they may refer to a direct connection or an indirect connection through an intermediate medium; and they may refer to the internal connection of two components. Those skilled in the art can understand the specific meaning of the above terms in this invention based on the specific circumstances. The invention will now be described in further detail with reference to the accompanying drawings.

[0041] Reference Figure 1-2 A magnetic field focusing and corrected electron beam acceleration system, comprising:

[0042] The electron gun uses a novel high-brightness, long-life nanocomposite cathode material to emit an electron beam with a specific energy distribution and low emissivity. The internal structure of the electron gun has been optimized to precisely control the electron beam emission angle and initial divergence.

[0043] The accelerator tube adopts a multi-stage acceleration structure. Each stage of the acceleration structure consists of a unique microwave resonant cavity, whose resonant frequency can be dynamically adjusted in the range of 5GHz-15GHz. The outer shell of the accelerator tube is made of a special low-loss, high thermal conductivity ceramic material, which can effectively dissipate heat and reduce microwave energy loss. An electron beam collimation device is provided between the accelerator tube and the electron gun to ensure that the electron beam accurately enters the accelerator tube.

[0044] The focusing coil is made of multi-layer high-temperature superconducting tape. The coil has a cooling channel inside, which can be introduced into the low-temperature medium such as liquid helium to achieve efficient cooling. The magnetic field distribution of the focusing coil is optimized through a special coil winding layout to generate a highly uniform focusing magnetic field with continuously adjustable magnetic field strength. Its magnetic field strength adjustment range can reach 0.1 Tesla to 1 Tesla, and the adjustment accuracy reaches ±0.001 Tesla.

[0045] The correction coil adopts a three-dimensional structure design and consists of multiple independently controlled sub-coils. It can generate a correction magnetic field in three dimensions of space. The strength of the correction magnetic field can be precisely adjusted between 10 Gauss and 1000 Gauss with an adjustment accuracy of ±1 Gauss. The correction coil and the focusing coil are isolated by a magnetic field coupling device to avoid mutual interference.

[0046] The control system includes high-precision sensors, a high-speed data acquisition card, and an intelligent controller. The sensors employ advanced electron beam diagnostic technology, enabling real-time and accurate measurement of multiple parameters such as the electron beam's position, energy, divergence, and beam current intensity. The data acquisition card collects sensor data at a sampling frequency exceeding 1000Hz. The intelligent controller, based on advanced machine learning algorithms and adaptive control strategies, predicts the dynamic trends of the electron beam using complex calculation models based on real-time acquired data. It precisely controls the magnetic field strength of the focusing and correction coils to achieve accurate focusing and correction of the electron beam. It also features fault diagnosis and automatic protection functions, allowing for rapid measures to protect equipment safety when system anomalies occur.

[0047] In this invention, the nanocomposite cathode material of the electron gun is synthesized through a specific preparation process, which includes tungsten-based material doped with silicon carbide nanoparticles. The preparation process includes steps such as high-temperature sintering and chemical vapor deposition, which enables the cathode to have high electron emission efficiency and good stability. The high-voltage power supply of the electron gun adopts a high-precision, low-ripple power supply module, and the output voltage stability is better than ±0.01%.

[0048] In this invention, the microwave resonant cavity of the accelerating tube adopts innovative designs such as an elliptical cavity and a gradually changing coupling structure, which can effectively improve the interaction efficiency between the microwave field and the electron beam. The vacuum system inside the accelerating tube uses a multi-stage vacuum pump group, and the ultimate vacuum degree can reach 1×10⁻ 8Below Pascal, this ensures that the electron beam is not affected by scattering from gas molecules during acceleration.

[0049] In this invention, the high-temperature superconducting tape of the focusing coil has a high critical current density (greater than 10). 6 A / cm 2 Low AC loss (less than 10⁻) 4 Special performance parameters such as W / m are used. The coil is wound using a non-inductive winding method to further improve the uniformity of the magnetic field. The magnetic field adjustment system of the focusing coil uses a high-precision current source with a current adjustment resolution of 0.1 mA.

[0050] In this invention, the sub-coils of the correction coil are miniaturized and made of high-strength, high-conductivity copper-nickel alloy. Each sub-coil is equipped with an independent drive circuit, which uses high-speed switching elements to achieve rapid switching and precise control of magnetic field strength. A magnetic field shield is provided around the correction coil to reduce external magnetic field interference.

[0051] In this invention, the intelligent controller of the control system stores a large number of electron beam behavior models and correction algorithm libraries, which can automatically select appropriate control strategies according to different application scenarios and electron beam characteristics. At the same time, the controller is connected to external devices through a high-speed communication interface to realize remote monitoring and operation, and can record and analyze system operation data in real time, providing a basis for system optimization and fault diagnosis.

[0052] This invention discloses a magnetic field focusing and correction method for accelerating an electron beam, comprising the following steps:

[0053] S1. The electron gun emits an electron beam. By precisely controlling parameters such as the cathode temperature and high voltage power supply voltage of the electron gun, the electron beam has a predetermined initial energy (e.g., 50keV-100keV), emissivity (less than 0.5mm·mrad), and divergence (less than 0.1°). After passing through the collimation device, the electron beam enters the accelerating tube with a high-precision incident angle (less than 0.01°).

[0054] S2. The accelerating tube dynamically adjusts the resonant frequency of the microwave resonant cavity and the input microwave power according to the energy requirements of the electron beam to accelerate the electron beam efficiently. During the acceleration process, parameters such as the vacuum degree and microwave field distribution inside the accelerating tube are monitored in real time to ensure a stable acceleration environment.

[0055] S3. The focusing coil calculates the initial focusing magnetic field strength based on the initial parameters of the electron beam and the energy changes during the acceleration phase through the control system, generates a focusing magnetic field to initially focus the electron beam, and continuously monitors the focusing state of the electron beam during the focusing process.

[0056] S4. The sensor monitors the position, energy, divergence and other state parameters of the electron beam in real time with an ultra-high sampling frequency, and transmits the data to the intelligent controller through the data acquisition card.

[0057] S5. The intelligent controller inputs the received real-time data into the pre-trained electron beam behavior prediction model, combines it with the algorithms in the correction algorithm library, calculates the strength and direction of the correction magnetic field, controls the correction coil to generate the correction magnetic field, and performs precise correction of the electron beam focus. During the correction process, the control parameters are continuously optimized to ensure that the electron beam always maintains the best focus state during acceleration. At the same time, the microwave parameters of the accelerating tube are dynamically adjusted according to the actual state of the electron beam to achieve synergistic optimization of acceleration and focusing.

[0058] S6. Regularly conduct comprehensive performance evaluations of the system, including indicators such as the final energy of the electron beam (target energy can reach 1MeV-10MeV), beam quality (e.g., beam uniformity greater than 95%), and focusing accuracy (focusing error less than 0.05mm). Based on the evaluation results, use machine learning algorithms to automatically optimize and upgrade the models and algorithms in the control system, continuously improving the overall performance of the system. Furthermore, during system operation, use intelligent diagnostic functions to promptly identify potential faults and take maintenance measures in advance to ensure the stable and reliable operation of the system.

[0059] In this invention, in step S3, the initial focusing magnetic field strength is calculated based on a multiphysics coupling simulation model, taking into account factors such as the space charge effect and relativistic effect of the electron beam. The formula is as follows: Where Bf is the focusing magnetic field strength (unit: Tesla), E0 is the initial energy of the electron beam (unit: electron volt), D0 is the spatial distance parameter corresponding to the initial divergence angle of the electron beam (unit: meter), L is the length of the accelerating tube (unit: meter), I is the electron beam current intensity (unit: ampere), ε is the electron beam emittance (unit: meter-radian), and m0 is the electron rest mass (9.10938356 × 10⁻⁻⁶). 31 kilograms), c is the speed of light in vacuum (299,792,458 meters per second), k1 and k2 are coefficients obtained by fitting a large amount of experimental data and simulation results. Furthermore, during the focusing process, an adaptive feedback control algorithm is used to fine-tune the focusing magnetic field strength in real time according to the actual focusing situation of the electron beam. The fine-tuning formula is: Where ΔBf is the adjustment amount of the focusing magnetic field strength (unit: Tesla), F is the deviation between the actual focusing position and the ideal focusing position of the electron beam (unit: meter), F0 is the preset focusing position deviation threshold (unit: meter), D is the deviation between the actual divergence and the initial divergence of the electron beam (unit: radians), D0 is the preset divergence deviation threshold (unit: radians), and k3 and k4 are adaptive adjustment coefficients that are updated in real time according to the dynamic changes of the electron beam.

[0060] In this invention, in step S5, the calculation of the strength and direction of the correction magnetic field adopts a neural network algorithm based on deep learning. The input layer of the neural network is the real-time state parameters of the electron beam, and the output layer is the strength and direction of the correction magnetic field. The training process uses a large amount of simulation and actual experimental data to ensure the accuracy and generalization ability of the algorithm. The generation of the correction magnetic field adopts pulse modulation technology. According to the dynamic changes of the electron beam, the pulse width (range of 1μs-100μs), frequency (range of 1kHz-100kHz) and amplitude of the correction magnetic field are precisely controlled to achieve fast and accurate correction of electron beam focusing. In addition, a fuzzy control strategy is introduced during the correction process to handle the uncertainties in the system and improve the stability and robustness of the correction.

[0061] In this invention, in step S6, the performance evaluation index system includes multiple quantitative indicators such as electron beam energy stability (fluctuation less than ±0.5%), beam current uniformity (greater than 95%), and divergence reduction rate (greater than 80%), as well as qualitative indicators such as imaging quality and processing accuracy of the electron beam in practical applications. The system optimization and upgrade process adopts reinforcement learning algorithm to automatically explore and optimize the parameter settings and algorithm strategies of the control system based on the performance evaluation results. At the same time, a fault prediction model is established, and based on big data analysis and machine learning technology, the possible fault types and times are predicted in advance, providing a scientific basis for preventive maintenance and ensuring the long-term stable operation of the system.

[0062] The above are merely preferred embodiments of the present invention, but the scope of protection of the present invention is not limited thereto. Any equivalent substitutions or modifications made by those skilled in the art within the scope of the technology disclosed in the present invention, based on the technical solution and inventive concept of the present invention, should be covered within the scope of protection of the present invention.

Claims

1. A magnetic field focusing and corrected electron beam acceleration system, characterized in that, include: The electron gun uses a nanocomposite cathode material, and its internal structure has been optimized to precisely control the electron beam emission angle and initial divergence. The accelerating tube adopts a multi-stage accelerating structure. Each stage of the accelerating structure consists of a microwave resonant cavity, and its resonant frequency is dynamically adjusted in the range of 5GHz-15GHz. The outer shell of the accelerating tube is made of low-loss, high-thermal-conductivity ceramic material. An electron beam collimation device is provided between the accelerating tube and the electron gun. The focusing coil is made of multi-layer high-temperature superconducting tape. The coil has a cooling channel inside and liquid helium cryogenic medium is introduced to achieve efficient cooling. The magnetic field distribution of the focusing coil is optimized through the coil winding layout to generate a uniform focusing magnetic field with continuously adjustable magnetic field strength. The correction coil adopts a three-dimensional structure design, consisting of multiple independently controlled sub-coils, which generate a correction magnetic field in three spatial dimensions. The correction coil and the focusing coil are isolated by a magnetic field coupling device to avoid mutual interference. The control system includes high-precision sensors, high-speed data acquisition cards, and intelligent controllers. The sensors employ electron beam diagnostic technology to measure the position, energy, divergence, and beam current intensity parameters of the electron beam in real time. The intelligent controller, based on machine learning algorithms and adaptive control strategies, predicts the dynamic change trend of the electron beam through a calculation model based on the real-time acquired data, and controls the magnetic field strength of the focusing coil and the correction coil to achieve focusing and correction of the electron beam.

2. The magnetic field focusing and corrected electron beam acceleration system according to claim 1, characterized in that, The nanocomposite cathode material of the electron gun is synthesized through a preparation process, which includes tungsten-based material doped with silicon carbide nanoparticles. The preparation process includes high-temperature sintering and chemical vapor deposition steps. The high-voltage power supply output voltage stability of the electron gun is better than ±0.01%.

3. The magnetic field focusing and corrected electron beam acceleration system according to claim 1, characterized in that, The microwave resonant cavity of the accelerating tube adopts an elliptical cavity and a gradually changing coupling structure design to improve the interaction efficiency between the microwave field and the electron beam. The vacuum system inside the accelerating tube uses a multi-stage vacuum pump group, and the ultimate vacuum degree can reach 1×10⁻ 8 Below Pascal.

4. The magnetic field focusing and corrected electron beam acceleration system according to claim 1, characterized in that, The high-temperature superconducting tape of the focusing coil has high critical current density and low AC loss performance parameters. The coil winding process adopts a non-inductive winding method to improve the magnetic field uniformity. The magnetic field adjustment system of the focusing coil adopts a current source adjustment resolution of 0.1 mA.

5. The magnetic field focusing and corrected electron beam acceleration system according to claim 1, characterized in that, The sub-coils of the correction coil are miniaturized and made of copper-nickel alloy. Each sub-coil is equipped with an independent drive circuit. The drive circuit uses high-speed switching elements to realize the switching and control of magnetic field strength. A magnetic field shield is provided around the correction coil to reduce external magnetic field interference.

6. The magnetic field focusing and corrected electron beam acceleration system according to claim 1, characterized in that, The intelligent controller of the control system stores an electron beam behavior model and a correction algorithm library. It automatically selects appropriate control strategies according to different application scenarios and electron beam characteristics. At the same time, the controller is connected to external devices through a high-speed communication interface to realize remote monitoring and operation, and records and analyzes system operation data in real time.

7. A magnetic field focusing and correction electron beam acceleration method according to any one of claims 1-6, characterized in that, Includes the following steps: S1. The electron gun emits an electron beam. By controlling the cathode temperature and high voltage power supply parameters of the electron gun, the electron beam has a predetermined initial energy, emissivity and divergence. After passing through the collimation device, the electron beam enters the accelerating tube at a high-precision incident angle. S2. The accelerating tube dynamically adjusts the resonant frequency of the microwave resonant cavity and the input microwave power according to the energy requirements of the electron beam to accelerate the electron beam efficiently. During the acceleration process, the vacuum degree and microwave field distribution parameters inside the accelerating tube are monitored in real time. S3. The focusing coil calculates the initial focusing magnetic field strength based on the initial parameters of the electron beam and the energy changes during the acceleration phase through the control system, generates a focusing magnetic field to initially focus the electron beam, and continuously monitors the focusing state of the electron beam during the focusing process. S4. The sensor monitors the position, energy, and divergence status parameters of the electron beam in real time and transmits the data to the intelligent controller through the data acquisition card. S5. The intelligent controller inputs the received real-time data into the pre-trained electron beam behavior prediction model, combines it with the algorithms in the correction algorithm library, calculates the strength and direction of the correction magnetic field, controls the correction coil to generate the correction magnetic field, corrects the focusing of the electron beam, continuously optimizes the control parameters during the correction process to ensure that the electron beam always maintains the best focusing state during acceleration, and dynamically adjusts the microwave parameters of the accelerating tube according to the actual state of the electron beam to achieve coordinated optimization of acceleration and focusing. S6. Regularly conduct comprehensive performance evaluations of the system, including the final energy of the electron beam, beam quality, and focusing accuracy. Based on the evaluation results, use machine learning algorithms to automatically optimize and upgrade the models and algorithms in the control system, continuously improving the overall performance of the system. Furthermore, during system operation, use intelligent diagnostic functions to promptly identify potential faults.

8. The magnetic field focusing and correction electron beam acceleration method according to claim 7, characterized in that, In step S3, the initial focusing magnetic field strength is calculated based on a multiphysics coupling simulation model, taking into account the space charge effect and relativistic effects of the electron beam. The formula is as follows: Where Bf is the focusing magnetic field strength, E0 is the initial energy of the electron beam, D0 is the spatial distance parameter corresponding to the initial divergence angle of the electron beam, L is the length of the accelerating tube, I is the electron beam current intensity, ε is the electron beam emittance, m0 is the electron rest mass, c is the speed of light in vacuum, and k1 and k2 are coefficients obtained by fitting a large amount of experimental data and simulation results. Furthermore, during the focusing process, an adaptive feedback control algorithm is used to fine-tune the focusing magnetic field strength in real time according to the actual focusing situation of the electron beam. The fine-tuning formula is: Where ΔBf is the adjustment amount of the focusing magnetic field strength, F is the deviation between the actual focusing position and the ideal focusing position of the electron beam, F0 is the preset focusing position deviation threshold, D is the deviation between the actual divergence and the initial divergence of the electron beam, D0 is the preset divergence deviation threshold, and k3 and k4 are adaptive adjustment coefficients.

9. The magnetic field focusing and correction electron beam acceleration method according to claim 7, characterized in that, In step S5, the calculation of the strength and direction of the correction magnetic field adopts a neural network algorithm based on deep learning. The input layer of the neural network is the real-time state parameters of the electron beam, and the output layer is the strength and direction of the correction magnetic field. The training process uses a large amount of simulation and actual experimental data to ensure the accuracy and generalization ability of the algorithm. The generation of the correction magnetic field adopts pulse modulation technology. According to the dynamic changes of the electron beam, the pulse width, frequency and amplitude of the correction magnetic field are controlled to achieve the correction of the electron beam focusing. In addition, fuzzy control strategy is introduced during the correction process to handle the uncertainty factors in the system and improve the stability and robustness of the correction.

10. The magnetic field focusing and correction electron beam acceleration method according to claim 7, characterized in that, In step S6, the performance evaluation index system includes multiple quantitative indicators such as the energy stability of the electron beam, beam uniformity, and divergence reduction rate, as well as qualitative indicators such as the imaging quality and processing accuracy of the electron beam in practical applications. The system optimization and upgrade process adopts reinforcement learning algorithm to automatically explore and optimize the parameter settings and algorithm strategies of the control system based on the performance evaluation results. At the same time, a fault prediction model is established to predict the possible fault types and times based on big data analysis and machine learning technology.

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