A focusing electrode assembly for an adjustable microfocus x-ray source

Abstract

The application relates to the technical field of X-ray regulation, in particular to a focusing electrode assembly of an adjustable micro-focus X-ray source, which comprises a bearing frame, and a shielding cover and a grounding system are arranged on the upper surface of the bearing frame. The focusing electrode assembly of the adjustable micro-focus X-ray source has high focusing precision and stable and reliable operation, adopts a multi-stage focusing structure composed of main focusing, auxiliary focusing and a ring-shaped shaping electrode, and can gradually converge and correct the electron beam, and the pre-adjustment and micron-level precise adjustment of an adjustable cathode mounting seat and the accurate positioning of a cathode-anode alignment reference block are combined, so that the electron beam is stably converged into a micro-focus, the X-ray quality and imaging resolution are optimized, meanwhile, the electrode insulation support column guarantees the insulation distance, the heat shielding cover and the cooling interface efficiently control the temperature, the shielding grounding system eliminates electromagnetic interference, the X-ray window alignment collimation sleeve guarantees the accurate output direction, and the overall structure meets multiple requirements.

Description

Technical Field

[0001] This invention relates to the field of X-ray modulation technology, and more particularly to a focusing electrode assembly for an adjustable microfocus X-ray source. Background Technology

[0002] The focusing electrode assembly of an X-ray source is the core structure used to accelerate, shape, and precisely focus the electron beam emitted by the filament. Its performance directly determines the X-ray focal spot size, brightness, and imaging resolution. The adjustable micro-focus X-ray source focusing electrode assembly proposed in this invention achieves micron-level dynamic adjustment of the cathode emission position by introducing an adjustable cathode mount, a fine-tuning screw assembly, and a piezoelectric micro-displacement actuator. Through a multi-level electrode system composed of main, auxiliary, and ring-shaped electrodes and a programmable voltage divider network, precise multi-segment focusing of the electron beam is achieved. Combined with dual closed-loop control of position and current, the focal spot remains stable over a long period. At the same time, a heat shield and cooling structure is set up to effectively suppress thermal drift. Compared with the prior art, this invention significantly improves the stability, adjustment accuracy, and imaging clarity of the micro-focus, and is suitable for high-resolution flaw detection and microstructure inspection. Therefore, there is a need for an adjustable micro-focus X-ray source focusing electrode assembly.

[0003] Existing adjustable microfocus X-ray sources often suffer from problems such as difficulty in accurately aligning the cathode position, unstable electron beam focusing, thermal drift leading to focus shift, and inability to dynamically optimize electrode potential, which affect imaging resolution and long-term stability.

[0004] To address the aforementioned issues, a search revealed a patent with publication number CN119816982A that discloses an electrode assembly. The paper proposes that "the electrode assembly has a structure in which a negative electrode, a separator, and a positive electrode are wound in a stacked state and have a central hole formed at the center of the electrode assembly. The electrode assembly includes: a negative electrode wound in a state where a negative electrode tab is engaged at a predetermined position; and a positive electrode having an inner end portion positioned closer to the central hole and an outer end portion positioned opposite to the inner end portion and further away from the central hole. The negative electrode, separator, and positive electrode are wound such that the inner end portion of the negative electrode is positioned closer to the central hole than the inner end portion of the positive electrode, and when the inner end portion of the positive electrode is connected to the center point of the central hole via a virtual line, the virtual line passes through the negative electrode tab." The aforementioned structure has a fixed winding position relationship between the negative and positive electrodes, limiting alignment accuracy. Positioning errors at the inner end portion can easily affect the overall electric field distribution, and the design of the tab passing through the virtual line has shortcomings in assembly and stability.

[0005] In light of this, in-depth research into the aforementioned issues led to the creation of this case. Summary of the Invention

[0006] The purpose of this invention is to provide a focusing electrode assembly for an adjustable microfocus X-ray source, in order to solve the problems mentioned above in the background art, such as the difficulty in accurately aligning the cathode position, unstable electron beam focusing, thermal drift causing focus shift, and the inability to dynamically optimize the electrode potential, which affect imaging resolution and long-term stability.

[0007] To achieve the above objectives, the present invention provides the following technical solution: a focusing electrode assembly for an adjustable microfocus X-ray source, comprising a support frame,

[0008] The upper surface of the support frame is welded with an X-ray tube housing. A vacuum-sealed tube shell is fitted inside the X-ray tube housing. A cathode support is connected to the inner side of the vacuum-sealed tube shell. A filament is provided on the upper surface of the cathode support. A main focusing electrode is connected to the upper surface of the cathode support. An adjustable cathode mounting base is provided above the cathode support. A fine-tuning screw assembly is provided above the adjustable cathode mounting base. A piezoelectric micro-displacement actuator is installed above the cathode support. A cathode and anode alignment reference block is provided inside the vacuum-sealed tube shell. One end of the cathode and anode alignment reference block is connected to an anode support. A shield and grounding system are installed on the upper surface of the support frame.

[0009] Preferably, the filament element is mounted above the filament support, which supports the filament element and maintains its spatial position relative to the main focusing electrode.

[0010] Preferably, an auxiliary focusing electrode and an annular shaping electrode are sequentially arranged in front of the main focusing electrode along the electron beam direction, and both the auxiliary focusing electrode and the annular shaping electrode are fixed insulated relative to the cathode support by electrode insulating support columns.

[0011] Preferably, the fine-tuning screw assembly is used to achieve pre-adjustment of the adjustable cathode mount relative to the cathode support, while the piezoelectric micro-displacement actuator is used to achieve real-time micro-displacement precision adjustment of the adjustable cathode mount.

[0012] Preferably, the filament component is electrically connected to the external circuit via a cathode high-voltage lead-out rod, and the main focusing electrode, auxiliary focusing electrode, and annular shaping electrode are electrically connected to the electrode voltage divider network module via focusing electrode potential lead-out rods.

[0013] Preferably, a vacuum lead-out current detection terminal is provided on the inner side of the vacuum-sealed tube shell. The vacuum lead-out current detection terminal is connected in series in the anode current detection circuit to detect the electron beam current intensity and feed the current signal back to the external control electronic module, thereby forming a dual closed-loop control system with the internal position sensing unit, consisting of a current closed loop and a position closed loop.

[0014] Preferably, a heat shield is provided inside the vacuum-sealed tube shell. The heat shield is located in the peripheral area of ​​the filament and the main focusing electrode to suppress the transmission of high-temperature radiation to the vacuum-sealed tube shell and the X-ray tube housing.

[0015] Preferably, the exterior of the X-ray tube housing is further provided with an X-ray window alignment sleeve for precise alignment of the X-ray beam emitted from the anode target in the window direction.

[0016] Preferably, the cooling interface provided on the outside of the X-ray tube housing is used to provide a cooling path to the anode support and the vacuum-sealed tube housing, while the shielding cover and grounding system are used to achieve electromagnetic shielding and grounding protection for the entire X-ray tube.

[0017] A focusing electrode assembly and method for an adjustable microfocus X-ray source, comprising the following steps:

[0018] S1. In the initial stage of installation, the cathode end is mechanically pre-aligned. By adjusting the initial position of the cathode support, the adjustable cathode mounting base, and the filament component, the filament component is accurately positioned in the opening area of ​​the main focusing electrode under the support of the filament bracket. The cathode component is then mechanically aligned relative to the anode support by using the fine-tuning screw assembly in conjunction with the cathode and anode alignment reference block.

[0019] S2. Set the potential of the multi-stage focusing electrode system, and output voltage to the electrode voltage divider network module through the external control electronic module, so that the main focusing electrode, auxiliary focusing electrode and ring shaping electrode form an initial potential distribution, so as to perform preliminary shaping and focusing of the electron beam emitted by the filament component.

[0020] S3. The cathode position is precisely adjusted at the micron level using a piezoelectric micro-displacement actuator. Driven by an external control electronic module, the cathode mounting base can be adjusted to generate micro-displacement. The internal position sensing unit detects the displacement information in real time and feeds it back to the external control electronic module, thereby realizing closed-loop precision correction of the cathode position.

[0021] S4. Obtain the anode current data of the electron beam through the vacuum lead-out current detection terminal and feed it back to the external control electronic module. The control module, in combination with the position closed-loop signal, further adjusts the potential output of the electrode voltage divider network module, so that the potential distribution of the main focusing electrode, auxiliary focusing electrode and ring shaping electrode is continuously optimized, thereby converging the electron beam into a smaller focus at the anode target.

[0022] S5. During the high-heat operation of the electron beam, thermal radiation is suppressed by a thermal shield set outside the filament and the main focusing electrode, and a cooling path is provided to the vacuum-sealed tube shell and the anode support through a cooling interface located outside the X-ray tube shell. At the same time, the electromagnetic shielding stability is maintained by the shield and the grounding system, so that the electron beam focus remains stable under thermal load conditions, thereby achieving stable high-resolution imaging of the micro-focus X-ray source.

[0023] Compared with the prior art, the beneficial effects of the present invention are:

[0024] 1. The focusing electrode assembly of this adjustable microfocus X-ray source adopts a multi-stage focusing structure consisting of a main focusing electrode, an auxiliary focusing electrode, and a ring-shaped shaping electrode. Combined with a programmable potential output from an external control electronic module, a specific electric field distribution is formed to converge and correct the electron beam step by step, ultimately forming a highly convergent microfocus on the anode target surface. Simultaneously, the adjustable cathode mounting base, combined with the pre-adjustment of the fine-tuning screw assembly and the micron-level precision adjustment of the piezoelectric micro-displacement actuator, ensures that the filament is always in the optimal emission center position, guaranteeing stable initial divergence angle and energy distribution of the electron beam. The cathode and anode alignment reference block provides precise assembly positioning, further improving the electron beam focusing accuracy and significantly optimizing X-ray output quality and imaging resolution.

[0025] 2. This adjustable microfocus X-ray source's focusing electrode assembly features an electrode insulation support column that ensures a stable insulation distance between each focusing electrode, preventing mechanical disturbances from affecting the focusing system. A heat shield protects the filament components and the main focusing electrode from high-temperature radiation, preventing thermal radiation from damaging the electrode's geometric stability and the vacuum environment. An external cooling interface efficiently dissipates heat through a cooling path, reducing system temperature rise. The shield and grounding system eliminate electromagnetic interference and form a X-ray shielding path, preventing stray electromagnetic fields and external noise from affecting electron beam stability. An X-ray window alignment sleeve achieves spatial alignment of the X-ray beam, ensuring accurate output direction. The overall structure addresses multiple requirements such as insulation, heat dissipation, and anti-interference, significantly improving the long-term stability and service life of the equipment. Attached Figure Description

[0026] Figure 1 This is a schematic diagram of the overall structure of the present invention;

[0027] Figure 2 This is a schematic cross-sectional view of the main body of the present invention;

[0028] Figure 3 This is a schematic diagram of the cathode assembly structure of the present invention;

[0029] Figure 4 This is a schematic diagram of the multi-stage focusing electrode structure of the present invention;

[0030] Figure 5This is a schematic diagram of the anode assembly structure of the present invention;

[0031] Figure 6 This is a schematic diagram of the connection structure of the electronic control and closed-loop control system of the present invention;

[0032] Figure 7 This is a schematic diagram of the thermal management system structure of the present invention;

[0033] Figure 8 This is a schematic diagram of the overall process of the present invention.

[0034] In the diagram: 1. Support frame; 2. X-ray tube housing; 3. Vacuum-sealed tube housing; 4. Cathode support; 5. Filament assembly; 6. Filament bracket; 7. Main focusing electrode; 8. Auxiliary focusing electrode; 9. Annular shaping electrode; 10. Electrode insulating support column; 11. Adjustable cathode mounting base; 12. Fine-tuning screw assembly; 13. Piezoelectric micro-displacement actuator; 14. Cathode high-voltage lead-out rod; 15. Focusing electrode potential lead-out rod; 16. Electrode voltage divider network module; 17. Vacuum lead-out current detection terminal; 18. Thermal shield; 19. X-ray window alignment collimating sleeve; 20. Cathode and anode alignment reference block; 21. Anode target; 22. Anode support; 23. Internal position sensing unit; 24. External control electronic module; 25. Cooling interface; 26. Shield and grounding system. Detailed Implementation

[0035] 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.

[0036] Please see Figure 1-8 The present invention provides a technical solution: a focusing electrode assembly for an adjustable microfocus X-ray source, including a support frame 1.

[0037] An X-ray tube housing 2 is welded to the upper surface of the support frame 1. A vacuum-sealed housing 3 is fitted inside the X-ray tube housing 2. A cathode support 4 is connected to the inner side of the vacuum-sealed housing 3. A filament component 5 is installed on the upper surface of the cathode support 4. A main focusing electrode 7 is connected to the upper surface of the cathode support 4. An adjustable cathode mounting base 11 is installed above the cathode support 4. A fine-tuning screw assembly 12 is installed above the adjustable cathode mounting base 11. A piezoelectric micro-displacement actuator 13 is installed above the cathode support 4. A cathode and anode alignment reference block 20 is installed inside the vacuum-sealed housing 3. One end of the cathode and anode alignment reference block 20 is connected to an anode support 22. A shield and grounding system 26 are installed on the upper surface of the support frame 1. The vacuum-sealed housing 3 provides a high-vacuum working environment for the core components inside the X-ray tube, avoiding scattering, energy loss, and component oxidation caused by collisions between the electron beam and air molecules, and ensuring the stability and focusing accuracy of the electron beam transmission.

[0038] Furthermore, the filament element 5 is mounted above the filament support 6, which supports the filament element 5 and maintains its spatial position relative to the main focusing electrode 7. Through the setting of the main focusing electrode 7, as the core component for electron beam focusing, its specific electrode shape and potential distribution can initially converge the diverging electron beam emitted by the filament element 5.

[0039] Furthermore, an auxiliary focusing electrode 8 and an annular shaping electrode 9 are sequentially arranged in front of the main focusing electrode 7 along the electron beam direction. Both the auxiliary focusing electrode 8 and the annular shaping electrode 9 are fixed insulated relative to the cathode support 4 by electrode insulating support column 10. By setting the annular shaping electrode 9, the electron beam can be further shaped and corrected on the basis of the focusing of the auxiliary focusing electrode 8. By optimizing the electrode potential distribution, stray electrons at the edge of the electron beam are eliminated, so that the cross-section of the electron beam forms a regular circular contour and the focus distortion is reduced.

[0040] Furthermore, the fine-tuning screw assembly 12 is used to achieve the pre-adjustment of the adjustable cathode mounting base 11 relative to the cathode support base 4, while the piezoelectric micro-displacement actuator 13 is used to achieve real-time micro-displacement precision adjustment of the adjustable cathode mounting base 11. Through the setting of the piezoelectric micro-displacement actuator 13, micron-level precision displacement adjustment of the adjustable cathode mounting base 11 can be achieved. Together with the internal position sensing unit 23, a position closed-loop control is formed to correct the cathode in real time.

[0041] Furthermore, the filament component 5 is electrically connected to the external power supply via the cathode high voltage lead-out rod 14. The main focusing electrode 7, the auxiliary focusing electrode 8, and the annular shaping electrode 9 are electrically connected to the electrode voltage divider network module 16 via the focusing electrode potential lead-out rod 15. The cathode high voltage lead-out rod 14 serves as a connection medium between the filament component 5 and the external high voltage power supply, enabling the safe and stable transmission of high voltage to the filament, providing energy for heating the filament to emit electrons and accelerating the electron beam.

[0042] Furthermore, a vacuum lead-out current detection terminal 17 is provided inside the vacuum-sealed tube shell 3. The vacuum lead-out current detection terminal 17 is connected in series in the anode current detection circuit to detect the electron beam current intensity and feed the current signal back to the external control electronic module 24. This forms a dual closed-loop control system with the internal position sensing unit 23, consisting of a current closed loop and a position closed loop. Through the setting of the internal position sensing unit 23, the micro-displacement information of the adjustable cathode mounting base 11 can be detected in real time, and the data can be fed back to the external control electronic module 24, forming a dual closed-loop control system with the vacuum lead-out current detection terminal 17.

[0043] Furthermore, a heat shield 18 is provided inside the vacuum-sealed tube shell 3. The heat shield 18 is located in the outer area of ​​the filament 5 and the main focusing electrode 7 to suppress the transmission of high-temperature radiation to the vacuum-sealed tube shell 3 and the X-ray tube housing 2. By setting the heat shield 18, the high temperature of the filament 5 and the heat radiation generated when the main focusing electrode 7 is working can be effectively shielded, reducing the transmission of heat to the vacuum-sealed tube shell 3 and the X-ray tube housing 2.

[0044] Furthermore, the exterior of the X-ray tube housing 2 is also provided with an X-ray window alignment and collimation sleeve 19, which is used to precisely collimate the X-ray beam emitted from the anode target 21 in the window direction. By setting the anode target 21, the kinetic energy of the electron beam can be efficiently converted into X-ray energy, and the emission direction of the X-ray can be constrained.

[0045] Furthermore, the cooling interface 25 provided on the outside of the X-ray tube housing 2 is used to provide a cooling path to the anode support 22 and the vacuum-sealed tube housing 3. At the same time, the shield and grounding system 26 are used to provide electromagnetic shielding and grounding protection for the entire X-ray tube. Through the setting of the cooling interface 25, a continuous cooling path is provided for the anode support 22 and the vacuum-sealed tube housing 3, which quickly removes the large amount of heat generated by the electron beam bombarding the anode target 21.

[0046] A focusing electrode assembly and method for an adjustable microfocus X-ray source, comprising the following steps:

[0047] S1. In the initial stage of installation, the cathode end is mechanically pre-aligned. By adjusting the initial position of the cathode support 4, the adjustable cathode mounting base 11 and the filament component 5, the filament component 5 is accurately positioned in the opening area of ​​the main focusing electrode 7 under the support of the filament bracket 6. The cathode component is then mechanically aligned with the anode support 22 by the fine-tuning screw assembly 12 in conjunction with the cathode and anode alignment reference block 20.

[0048] S2. Set the potential of the multi-stage focusing electrode system, and output voltage to the electrode voltage divider network module 16 through the external control electronic module 24, so that the main focusing electrode 7, the auxiliary focusing electrode 8 and the ring shaping electrode 9 form an initial potential distribution, so as to perform preliminary shaping and focusing of the electron beam emitted by the filament 5.

[0049] S3. The position of the cathode is precisely adjusted at the micron level using the piezoelectric micro-displacement actuator 13. Under the drive of the external control electronic module 24, the adjustable cathode mounting base 11 can generate micro-displacement. The internal position sensing unit 23 detects the displacement information in real time and feeds it back to the external control electronic module 24, thereby realizing closed-loop precision correction of the cathode position.

[0050] S4. Obtain the anode current data of the electron beam through the vacuum lead-out current detection terminal 17 and feed it back to the external control electronic module 24. The control module, in combination with the position closed-loop signal, further adjusts the potential output of the electrode voltage divider network module 16, so that the potential distribution of the main focusing electrode 7, the auxiliary focusing electrode 8 and the ring shaping electrode 9 is continuously optimized, thereby causing the electron beam to converge into a smaller focus at the anode target 21.

[0051] S5. During the high-heat operation of the electron beam, thermal radiation is suppressed by the thermal shield 18 located outside the filament 5 and the main focusing electrode 7, and a cooling path is provided to the vacuum-sealed tube shell 3 and the anode support 22 through the cooling interface 25 located outside the X-ray tube housing 2. At the same time, the electromagnetic shielding stability is maintained by the shield and the grounding system 26, so that the electron beam focus remains stable under thermal load conditions for a long time, thereby realizing stable high-resolution imaging of the micro-focus X-ray source.

[0052] Working principle: First, the support frame 1 serves as the overall support base. A vacuum-sealed tube shell 3 is fitted inside the X-ray tube housing 2 fixed above it to create a high-vacuum electron beam generation environment. A cathode support 4 is fixed inside the vacuum-sealed tube shell 3. The filament 5, positioned above the cathode support 4, is stably supported by the filament bracket 6, forming the initial electron beam emission and acceleration structure with the main focusing electrode 7 behind it. An adjustable cathode mounting base 11 is installed on the cathode support 4. Its position can be pre-adjusted during initial installation using a fine-tuning screw assembly 12, and the micron-level position of the electron beam emission source is achieved using a piezoelectric micro-displacement actuator 13. Precise adjustments are made to ensure that the filament 5 is always in the optimal emission center position, guaranteeing the stability of the initial divergence angle and energy distribution of the electron beam. To ensure precise geometric alignment between the cathode and anode sides, a cathode and anode alignment reference block 20 is provided inside the vacuum-sealed housing 3. This reference block provides precise assembly positioning, and its end is connected to the anode support 22, allowing the anode target 21 to be precisely positioned in the electron beam focusing area. During the focusing process, the filament 5 emits electrons after heating, which are accelerated by the high voltage applied by the cathode high-voltage lead-out rod 14. The electron beam enters the multi-stage focusing system consisting of the main focusing electrode 7, the auxiliary focusing electrode 8, and the annular shaping electrode 9. In the focal electrode structure region, each electrode is connected to the electrode voltage divider network module 16 via the focusing electrode potential lead-out rod 15. An external control electronic module 24 outputs a programmable potential, causing the multi-stage electrodes to form a specific electric field distribution. This allows for the gradual convergence, shaping, and correction of the electron beam, ultimately resulting in a highly convergent micro-focus on the surface of the anode target 21. During this process, the electrode insulation support column 10 ensures a stable insulation distance between the electrodes, preventing mechanical disturbances from affecting the multi-stage focusing system. When the equipment generates a large amount of heat during operation, a heat shield 1 is installed inside the vacuum-sealed shell 3 to prevent thermal radiation from affecting the electrode geometric stability and the vacuum environment. 8. It is used to shield the high-temperature radiation generated by the filament 5 and the main focusing electrode 7. In addition, a cooling interface 25 is provided on the outside of the X-ray tube housing 2. Heat is conducted to the anode support 22 and the vacuum-sealed tube housing 3 through the cooling path, thereby effectively reducing the system temperature rise. In addition, the shielding cover and grounding system 26 can eliminate electromagnetic interference and form a radiation shielding path to avoid external noise and stray electromagnetic fields from affecting the stability of the electron beam. In order to ensure the accuracy of the X-ray output direction, an X-ray window alignment and collimation sleeve 19 is provided on the outside of the housing to spatially collimate the X-ray beam generated by the anode target 21, so as to ensure the quality of the final output radiation and the imaging resolution.

[0053] Although embodiments of the invention have been shown and described, it will be understood by those skilled in the art that various changes, modifications, substitutions and alterations can be made to these embodiments without departing from the principles and spirit of the invention, the scope of which is defined by the appended claims and their equivalents.

Claims

1. A focusing electrode assembly for an adjustable microfocus X-ray source, comprising a support frame (1), characterized in that: The upper surface of the support frame (1) is welded with an X-ray tube housing (2). A vacuum-sealed tube housing (3) is fitted inside the X-ray tube housing (2). A cathode support (4) is connected to the inner side of the vacuum-sealed tube housing (3). A filament component (5) is provided on the upper surface of the cathode support (4). A main focusing electrode (7) is connected to the upper surface of the cathode support (4). An adjustable cathode mounting base (11) is provided above the cathode support (4). A fine-tuning screw assembly (12) is provided above the adjustable cathode mounting base (11). A piezoelectric micro-displacement actuator (13) is installed above the cathode support (4). A cathode and anode alignment reference block (20) is provided inside the vacuum-sealed tube housing (3). An anode support (22) is connected to one end of the cathode and anode alignment reference block (20). A shield and grounding system (26) are installed on the upper surface of the support frame (1).

2. The focusing electrode assembly of an adjustable microfocus X-ray source according to claim 1, characterized in that: The filament component (5) is mounted above the filament support (6), which supports the filament component (5) and maintains its spatial position relative to the main focusing electrode (7).

3. The focusing electrode assembly of an adjustable microfocus X-ray source according to claim 1, characterized in that: An auxiliary focusing electrode (8) and an annular shaping electrode (9) are sequentially arranged in front of the main focusing electrode (7) along the electron beam direction. Both the auxiliary focusing electrode (8) and the annular shaping electrode (9) are fixed insulated relative to the cathode support (4) by an electrode insulating support column (10).

4. The focusing electrode assembly of an adjustable microfocus X-ray source according to claim 1, characterized in that: The fine-tuning screw assembly (12) is used to achieve the pre-adjustment of the adjustable cathode mount (11) relative to the cathode support (4), while the piezoelectric micro-displacement actuator (13) is used to achieve real-time micro-displacement precision adjustment of the adjustable cathode mount (11).

5. The focusing electrode assembly of an adjustable microfocus X-ray source according to claims 1 and 3, characterized in that: The filament component (5) is electrically connected to the outside via the cathode high voltage lead-out rod (14), and the main focusing electrode (7), the auxiliary focusing electrode (8), and the annular shaping electrode (9) are electrically connected to the electrode voltage divider network module (16) via the focusing electrode potential lead-out rod (15).

6. The focusing electrode assembly of an adjustable microfocus X-ray source according to claim 1, characterized in that: The vacuum-sealed housing (3) is provided with a vacuum lead-out current detection terminal (17) inside. The vacuum lead-out current detection terminal (17) is connected in series in the anode current detection circuit to detect the electron beam intensity and feed the current signal back to the external control electronic module (24), thereby forming a dual closed-loop control system with the internal position sensing unit (23) for current closed loop and position closed loop.

7. The focusing electrode assembly of an adjustable microfocus X-ray source according to claim 1, characterized in that: A heat shield (18) is provided inside the vacuum-sealed tube shell (3). The heat shield (18) is located in the outer area of ​​the filament (5) and the main focusing electrode (7) to suppress the transmission of high-temperature radiation to the vacuum-sealed tube shell (3) and the X-ray tube housing (2).

8. The focusing electrode assembly of an adjustable microfocus X-ray source according to claim 1, characterized in that: The X-ray tube housing (2) is also provided with an X-ray window alignment sleeve (19) on the outside, which is used to accurately align the X-ray beam emitted from the anode target (21) in the window direction.

9. The focusing electrode assembly of an adjustable microfocus X-ray source according to claim 8, characterized in that: The cooling interface (25) provided on the outside of the X-ray tube housing (2) is used to provide a cooling path to the anode support (22) and the vacuum-sealed tube housing (3). At the same time, the shield and grounding system (26) are used to achieve electromagnetic shielding and grounding protection for the entire X-ray tube.

10. A focusing electrode assembly and method for an adjustable microfocus X-ray source, as described in any one of claims 1-9, characterized in that... Includes the following steps: This method is used to achieve precise alignment and focus optimization of the focusing electrode assembly of an adjustable microfocus X-ray source. The steps include: S1. In the initial stage of installation, the cathode end is mechanically pre-aligned. By adjusting the initial position of the cathode support (4), the adjustable cathode mounting base (11) and the filament (5), the filament (5) is accurately positioned in the opening area of ​​the main focusing electrode (7) under the support of the filament bracket (6). The cathode assembly is then mechanically aligned with the anode support (22) by using the fine-tuning screw assembly (12) in conjunction with the cathode and anode alignment reference block (20). S2. Set the potential of the multi-stage focusing electrode system and output voltage to the electrode voltage divider network module (16) through the external control electronic module (24) so ​​that the main focusing electrode (7), the auxiliary focusing electrode (8) and the ring shaping electrode (9) form an initial potential distribution to perform preliminary shaping and convergence of the electron beam emitted by the filament (5). S3. The position of the cathode is precisely adjusted at the micrometer level using a piezoelectric micro-displacement actuator (13). Under the drive of the external control electronic module (24), the adjustable cathode mounting base (11) generates micro-displacement. The internal position sensing unit (23) detects the displacement information in real time and feeds it back to the external control electronic module (24), thereby realizing closed-loop precision correction of the cathode position. S4. Obtain the anode current data of the electron beam through the vacuum lead-out current detection terminal (17) and feed it back to the external control electronic module (24). The control module further adjusts the potential output of the electrode voltage divider network module (16) in combination with the position closed-loop signal, so that the potential distribution of the main focusing electrode (7), the auxiliary focusing electrode (8) and the ring shaping electrode (9) is continuously optimized, so that the electron beam converges into a smaller focus at the anode target (21). S5. During the operation of the electron beam generating high heat, thermal radiation is suppressed by the heat shield (18) set outside the filament (5) and the main focusing electrode (7), and a cooling path is provided to the vacuum-sealed tube shell (3) and the anode support (22) through the cooling interface (25) located outside the X-ray tube shell (2). At the same time, the electromagnetic shielding stability is maintained by the shield and the grounding system (26), so that the electron beam focus remains stable under thermal load conditions, thereby realizing stable high-resolution imaging of the micro-focus X-ray source.

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