Electron beam centering device and centering method

Abstract

The invention provides an electron beam centering device and a centering method, which specifically include the following steps: generating an electron beam in a vacuum state; applying a deflection current to a deflection coil with a certain step length, and recording the reading of an ammeter; using a computer to analyze the scanning process to obtain the deflection current applied when the reading of the ammeter is the smallest; repeating the above steps to obtain electron beam centering parameters, thereby solving the problem that the traditional electron beam centering device has a complex structure and is time-consuming and labor-intensive to adjust. The electron beam centering is completed by scanning, which greatly improves the centering accuracy and can realize the intelligence of the adjustment process. The centering device has a simple structure and is easy to operate.

Description

Technical Field

[0001] The invention relates to the technical field of electron beam centering, and in particular to an electron beam centering device and a centering method. Background Art

[0002] An electron beam is a collection of electrons with high energy density. The electrons generated by the cathode in the electron gun are accelerated to a very high speed (0.3-0.7 times the speed of light) under the action of the high voltage (25-300KV) accelerating electric field between the anode and cathode. After being converged by a lens, a dense high-speed electron stream is formed.

[0003] In recent years, electron beams have been widely used in the fields of welding, imaging, X-ray production, and biological sterilization. These devices usually include electron sources, focusing lenses, targets, or sample holders. Due to the existence of machining errors, the coaxiality of these components cannot be guaranteed, which can easily cause the electron beam to deviate from the predetermined target area. In order to solve the problem of the electron beam deviating from the predetermined target area, a deflector is usually required. However, the introduction of a deflector makes the structure of the electron beam centering device complex, and the adjustment is time-consuming and labor-intensive. Summary of the invention

[0004] The invention discloses an electron beam centering device and a centering method, which solve the problems of complex structure and time-consuming and labor-intensive adjustment of traditional electron beam centering devices. The electron beam centering is completed by scanning, which greatly improves the centering accuracy and realizes the intelligent adjustment process.

[0005] To achieve the above object, the technical solution of the present invention is specifically implemented as follows:

[0006] In one aspect, the present invention discloses an electron beam centering method, comprising the following steps:

[0007] In a vacuum state, an electron beam is generated;

[0008] Apply deflection current to the deflection coil at a certain step length and record the reading of the ammeter;

[0009] The computer analyzes the scanning process and obtains the deflection current applied when the current meter reading is minimum;

[0010] Repeat the above steps to obtain the electron beam centering parameters.

[0011] Furthermore, the deflection current is within the interval [-I, +I].

[0012] On the other hand, the present invention discloses an electron beam centering device, comprising an electron gun, an electron beam tube, a detection tube, a deflection coil, a galvanometer and a computer, wherein the electron gun is used to emit a high-speed electron flow to form an electron beam; the electron beam tube is used to provide a running channel for the electron beam; the detection tube is arranged inside the electron beam tube, and a through hole is opened in the center of the detection tube to detect the centering of the electron beam in real time; the deflection coil is used to adjust the direction of the electron beam; the galvanometer is electrically connected to the detection tube to display the current value of the electron beam passing through the detection tube and transmit it to the computer; the computer is used to receive and process the current value of the electron beam passing through the detection tube detected by the galvanometer and control the deflection current in the deflection coil.

[0013] Furthermore, the electron beam tube is made of non-magnetic metal or alloy.

[0014] Furthermore, the deflection coils are in two groups, including a horizontal direction coil group and a vertical direction coil group. The horizontal direction coil group is used to adjust the electron beam in the horizontal and vertical directions, and the vertical direction coil group is used to adjust the electron beam in the horizontal direction.

[0015] Furthermore, the detection tube is a good conductor, and the detection tube is welded inside the electron beam tube through an insulating member.

[0016] Furthermore, the insulating member is made of insulating high temperature resistant material.

[0017] Furthermore, the detection tube is formed by brazing a high temperature resistant conductor and a high temperature resistant insulator.

[0018] Beneficial technical effects:

[0019] 1. The present invention discloses an electron beam centering method, which specifically comprises the following steps: generating an electron beam in a vacuum state; applying a deflection current of a certain step length to a deflection coil, and recording the reading of an ammeter; analyzing the scanning process by a computer to obtain the deflection current applied when the reading of the ammeter is the smallest; repeating the above steps to obtain electron beam centering parameters, thereby solving the problem that the traditional electron beam centering device has a complex structure and is time-consuming and labor-intensive to adjust, and completing the centering of the electron beam by scanning, thereby greatly improving the centering accuracy and realizing the intelligentization of the adjustment process;

[0020] 2. In the present invention, the electron beam tube is made of non-magnetic metal or alloy, which reduces the interference of the electron beam tube on the direction of the electron beam;

[0021] 3. In the present invention, the computer is used to receive and process the current value of the electron beam passing through the detection tube detected by the ammeter and control the deflection current in the deflection coil, so that the centering process of the electron beam can be intelligently controlled, saving time and effort;

[0022] 4. In the present invention, the deflection coils are divided into two groups, including a horizontal direction coil group and a vertical direction coil group. The horizontal direction coil group is used to adjust the electron beam in the horizontal and vertical directions, and the vertical direction coil group is used to adjust the electron beam in the horizontal direction. The electron beam can be adjusted in two directions. BRIEF DESCRIPTION OF THE DRAWINGS

[0023] In order to more clearly illustrate the technical solution of the present invention, the drawings required for describing the embodiments are briefly introduced below.

[0024] Figure 1 A flowchart of the steps of an electron beam centering method according to the present invention;

[0025] Figure 2 It is a schematic diagram of the principle of an electron beam centering device according to the present invention;

[0026] Figure 3 A cross-sectional view of a deflection coil in an electron beam centering device according to the present invention;

[0027] Figure 4 This is a typical detection curve diagram of an electron beam centering device described in the present invention. DETAILED DESCRIPTION

[0028] Embodiments of the present invention are described in detail below, examples of which are shown in the accompanying drawings, wherein the same or similar reference numerals throughout represent the same or similar elements or elements having the same or similar functions. The embodiments described below with reference to the accompanying drawings are exemplary and are only used to explain the present invention, and cannot be understood as limiting the present invention.

[0029] The embodiments of the present invention are described in detail below with reference to the accompanying drawings.

[0030] In one aspect, the present invention discloses an electron beam centering method, see Figure 1 , the electron beam centering method comprises the following steps:

[0031] S1: Produce electron beam in vacuum state;

[0032] Specifically, in a ray tube or electron gun, a vacuum device is used to evacuate the interior to a better vacuum state, and current is applied through the cathode filament to generate a large number of electrons. A strong electric field is formed between the filament and the anode through a high-voltage power supply, and the electrons are accelerated from the filament and fly into the electron beam tube.

[0033] S2: Apply deflection current to the deflection coil at a certain step length and record the reading of the ammeter;

[0034] Specifically, when the electron beam is centered, the high-speed electron beam will pass through the detection tube. At this time, the ammeter will have a reading. A computer is used to apply a deflection current to the deflection coil in the [-I, +I] interval with a certain step size, and the current reading I displayed on the ammeter connected to the detection tube is recorded.

[0035] S3: The computer analyzes the scanning process and obtains the deflection current applied when the current meter reading is minimum;

[0036] Specifically, when the electron beam passing through the detection tube increases, the ammeter reading decreases, and when the electron beam passing through the detection tube decreases, the ammeter reading increases, that is, the electron beam deviates; when the ammeter reading is the smallest, it means that the electron beam passing through the detection tube is the largest at this time, that is, it reaches the best centering state. The computer analyzes the scanning process and obtains the deflection current when the ammeter reading is the smallest.

[0037] S4: Repeat the above steps to obtain the electron beam centering parameters.

[0038] Specifically, the same steps and processes are performed on other deflection coils to finally obtain the electron beam centering parameters.

[0039] Another aspect of the present invention discloses an electron beam centering device, which includes an electron gun, an electron beam tube, a detection tube, a deflection coil, an ammeter and a computer, wherein the electron gun is used to emit a high-speed electron flow to form an electron beam; the electron beam tube is used to provide a running channel for the electron beam, preferably, the electron beam tube is made of non-magnetic metal or alloy, which reduces the interference with the direction of the electron beam; the detection tube is arranged inside the electron beam tube, and a through hole is opened in the center of the detection tube to detect the centering of the electron beam in real time, preferably, the detection tube is brazed together by a high-temperature resistant conductor and a high-temperature resistant insulator, and the thermal expansion coefficients of the two materials used must be well matched; the deflection coil is used to adjust the direction of the electron beam, preferably, see Figure 3 The deflection coils are divided into two groups, including a horizontal coil group and a vertical coil group. The horizontal coil group is used to adjust the electron beam in the horizontal and vertical directions, and the vertical coil group is used to adjust the electron beam in the horizontal direction. The ammeter is electrically connected to the detection tube to display the current value of the electron beam passing through the detection tube and transmit it to the computer. The computer is used to receive and process the current value of the electron beam passing through the detection tube detected by the ammeter and control the deflection current in the deflection coil.

[0040] The working principle of the electron beam centering device disclosed in the present invention can be found in Figure 2Specifically, the electron gun emits a high-speed electron flow to form an electron beam. The computer controls the deflection current to be applied to the deflection coil with a certain step length to adjust the direction of the electron beam. The electron beam moves along the electron beam tube and flows through the detection tube. The ammeter connected to the monitoring tube detects the electron beam flowing through the detection tube in real time, displays the current reading, and transmits the reading to the computer. The computer controls the current applied to the deflection coil and applies it in sequence with a certain step length within the interval [-I, +I]. The computer analyzes this scanning process. When the ammeter reading is the smallest, it is the appropriate deflection current. The computer scans the other groups of deflection coils in the same steps in sequence to obtain the centering parameters; its detection curve is as follows Figure 4 As shown, when the electron beam passing through the detection tube increases, the ammeter reading decreases. When the ammeter reading is minimum, the electron beam passing through is the largest, which is the best centering state.

[0041] It is understandable that in common laboratories, picoammeters and other equipment are used to test current. The ammeter in this invention can actually be replaced by an easily integrated circuit or sensor, so that the electron beam alignment can be achieved through PLC programming, thereby realizing fully automatic alignment of the electron beam.

[0042] Those skilled in the art will appreciate that the embodiments of the present application may be provided as methods, systems, or computer program products. Therefore, the present application may adopt the form of a complete hardware embodiment, a complete software embodiment, or an embodiment in combination with software and hardware. Moreover, the present application may adopt the form of a computer program product implemented in one or more computer-usable storage media (including but not limited to disk storage, CD-ROM, optical storage, etc.) that include computer-usable program code.

[0043] The present application is described with reference to the flowcharts and / or block diagrams of the methods, devices (systems), and computer program products according to the embodiments of the present application. It should be understood that each process and / or box in the flowchart and / or block diagram, as well as the combination of the processes and / or boxes in the flowchart and / or block diagram, can be implemented by computer program instructions. These computer program instructions can be provided to a processor of a general-purpose computer, a special-purpose computer, an embedded processor, or other programmable data processing device to generate a machine, so that the instructions executed by the processor of the computer or other programmable data processing device generate instructions for implementing the processes in the flowchart and / or block diagram. Figure 1 A process or multiple processes and / or boxes Figure 1 A device that provides the functions specified in a block or multiple blocks.

[0044] These computer program instructions may also be stored in a computer-readable memory capable of directing a computer or other programmable data processing device to operate in a specific manner, so that the instructions stored in the computer-readable memory produce an article of manufacture comprising an instruction device, which implements the process Figure 1 A process or multiple processes and / or boxes Figure 1 A function specified in one or more boxes.

[0045] These computer program instructions can also be loaded onto a computer or other programmable data processing device so that a series of operating steps are executed on the computer or other programmable device to produce a computer-implemented process, thereby providing instructions for implementing the process. Figure 1 A process or multiple processes and / or boxes Figure 1 The steps for the functions specified in one or more boxes.

[0046] In the description of this specification, the description with reference to the terms "one embodiment", "some embodiments", "examples", "specific examples", or "some examples" means that the specific features, structures, materials or characteristics described in conjunction with the embodiment or example are included in at least one embodiment or example of the present invention. In this specification, the schematic representation of the above terms does not necessarily refer to the same embodiment or example. Moreover, the specific features, structures, materials or characteristics described may be combined in any one or more embodiments or examples in a suitable manner.

[0047] The above embodiments are only descriptions of the preferred implementation modes of the present invention, and are not intended to limit the scope of the present invention. Without departing from the design spirit of the present invention, various modifications and improvements made to the technical solutions of the present invention by ordinary engineering and technical personnel in the field should fall within the protection scope determined by the claims of the present invention.

Claims

1. An electron beam centering method, characterized in that: The following steps are involved: In a vacuum state, an electron beam is generated; Apply deflection current to the deflection coil at a certain step length and record the reading of the ammeter; The computer analyzes the scanning process and obtains the deflection current applied when the current meter reading is minimum; Repeat the above steps to obtain the electron beam centering parameters; The deflection current is within the interval [-I, +I]; Includes an electron beam centering device, including: Electron gun, used to emit high-speed electron flow to form an electron beam; An electron beam tube, used to provide a running channel for the electron beam; A detection tube, which is arranged inside the electron beam tube and has a through hole at the center thereof for real-time detection of the centering of the electron beam; Deflection coils, used to adjust the direction of the electron beam; An ammeter, which is electrically connected to the detection tube and is used to display the current value of the electron beam passing through the detection tube and transmit it to a computer; The computer is used for receiving and processing the current value of the electron beam passing through the detection tube detected by the galvanometer and controlling the deflection current in the deflection coil.

2. The electron beam centering method according to claim 1, characterized in that: The electron beam tube is made of non-magnetic metal or alloy.

3. The electron beam centering method according to claim 1, characterized in that: The deflection coils are divided into two groups, including a horizontal direction coil group and a vertical direction coil group. The horizontal direction coil group is used to adjust the electron beam in the vertical direction, and the vertical direction coil group is used to adjust the electron beam in the horizontal direction.

4. The electron beam centering method according to claim 1, characterized in that: The detection tube is a good conductor, and the detection tube is welded inside the electron beam tube through an insulating member.

5. The electron beam centering method according to claim 4, characterized in that: The insulating member is made of insulating high temperature resistant material.

6. The electron beam centering method according to claim 1, characterized in that: The detection tube is formed by brazing a high temperature resistant conductor and a high temperature resistant insulator.

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