Radiation generating device and radiation tube

Abstract

The application discloses a kind of ray generating device and ray tube, it is related to ray tube technical field.Ray generating device includes: electron beam emission module, beam expander module, electron beam correction module and anode target;Along the first direction, electron beam emission module, beam expander module, electron beam correction module and anode target are sequentially arranged;Electron beam emission module is used to emit electron beam;Beam expander module is located in the side of electron beam emission module close to anode target;Beam expander module is used to expand electron beam;Electron beam correction module is located in the side of beam expander module close to anode target;Electron beam correction module is used to shape after electron beam expansion;After shaping by electron beam correction module, electron beam is used to bombard anode target, to make anode target produce ray.The technical scheme of the application improves the micro-focus formation stability and ray output stability when electron beam bombards target material.

Description

Technical Field

[0001] The present invention relates to the field of X-ray tube technology, and in particular to a X-ray generating device and an X-ray tube. Background Technology

[0002] Microfocus X-ray tubes typically generate X-rays by bombarding an anode target with an electron beam. The generated X-rays can be used for imaging, detection, and other applications.

[0003] In existing microfocus X-ray tubes, an electron optical lens system is typically used to focus the electron beam onto the anode target surface, forming a tiny focal spot. To further reduce the focal spot size, current techniques use multiple stages of electrostatic or magnetic lenses to progressively compress the electron beam, allowing it to bombard the anode target with the smallest possible beam size. However, the electron beam, after continuous compression and focusing, has a small beam diameter when it enters the subsequent correction structure. This results in lower sensitivity of the correction structure to adjusting the electron beam current distribution, astigmatism, and beam spot morphology, leading to increased focal spot size, focal spot drift, and decreased X-ray output stability. Furthermore, according to the principles of electron optical imaging, obtaining a smaller electron beam focal spot usually requires reducing the electron optical magnification. However, as the magnification decreases, the electron beam current intensity also decreases. Therefore, traditional electron optical systems struggle to simultaneously achieve ultra-microfocus formation and high-brightness X-ray output. Summary of the Invention

[0004] The present invention provides a radiation generating device and a radiation tube to improve the stability of microfocus formation and radiation output when an electron beam bombards a target.

[0005] The first aspect of the present invention provides a radiation generating device, which includes: an electron beam emitting module, a beam expanding module, an electron beam correction module, and an anode target; Along the first direction, the electron beam emitting module, the beam expanding module, the electron beam correction module, and the anode target are arranged in sequence; The electron beam emitting module is used to emit an electron beam; The beam expanding module is located on the side of the electron beam emitting module closer to the anode target; the beam expanding module is used to expand the electron beam. The electron beam correction module is located on the side of the beam expander module closer to the anode target; the electron beam correction module is used to shape the expanded electron beam. The electron beam, after being shaped by the electron beam correction module, is used to bombard the anode target to cause the anode target to generate radiation.

[0006] Optionally, the radiation generating device may also include: extraction electrodes; The extraction electrode is located between the electron beam emission module and the beam expander module; The extraction electrode has a positive potential relative to the electron beam emission module; The extraction electrode is used to extract the electron beam with a divergence angle less than or equal to the preset divergence angle, and to emit the electron beam with a divergence angle less than or equal to the preset divergence angle to the beam expander module.

[0007] Optionally, the beam expanding module includes a deceleration electrode and an anode electrode; The anode electrode is located on the side of the deceleration electrode closer to the anode target; The deceleration electrode has a negative potential relative to the extraction electrode, and the anode electrode is grounded.

[0008] Optionally, along the first direction, the distance between the deceleration electrode and the anode electrode is L1, the distance between the deceleration electrode and the electron beam emission module is L2, and the distance between the deceleration electrode and the anode target is L3; Where L1 < L2; L2 < L3.

[0009] Optionally, the extraction electrode has an extraction electrode aperture through which the electron beam passes; the aperture of the extraction electrode aperture is d1. The deceleration electrode has a deceleration electrode hole through which the electron beam passes; the diameter of the deceleration electrode hole is d2; The anode electrode has an anode electrode aperture through which the electron beam passes; Where d1 < d2 / 2.

[0010] Optionally, the radiation generating device may also include: an emitter alignment mechanism, an extractor alignment mechanism, and an anode alignment mechanism; The emitter alignment mechanism is connected to the electron beam emission module, the extraction electrode alignment mechanism is connected to the extraction electrode, and the anode alignment mechanism is connected to the anode electrode. The emitter alignment mechanism is used to adjust the position of the electron beam emitting module along the second direction, the extraction electrode alignment mechanism is used to adjust the position of the extraction electrode along the second direction, and the anode alignment mechanism is used to adjust the position of the anode electrode along the second direction, so that the transmission axis of the electron beam emitted by the electron beam emitting module, the extraction electrode hole, the deceleration electrode hole, and the anode electrode hole are aligned along the first direction; The second direction intersects with the first direction.

[0011] Optionally, the electron beam emission module includes a tungsten single crystal emission tip and a suppression electrode disposed around the tungsten single crystal emission tip; A zirconium oxide layer is disposed on the surface of the tungsten single crystal emission tip; the tungsten single crystal emission tip is used to generate the electron beam. The suppression electrode includes an exit opening through which the electron beam passes, and the suppression electrode is used to suppress the influence of the external electric field and / or external magnetic field of the electron beam emission module on the electron beam.

[0012] Optionally, along the first direction, the distance between the tungsten single crystal emission tip and the extraction electrode is L4; Where L4 ≥ 3mm.

[0013] Optionally, the electron beam correction module is an astigmatism reducer.

[0014] A second aspect of the present invention provides a radiation tube comprising: the radiation generating apparatus according to any one of claims 1-9.

[0015] The technical solution of this invention involves arranging an electron beam emitting module, a beam expander, an electron beam correction module, and an anode target sequentially along a first direction in a radiation generating device. This allows the electron beam emitted by the electron beam emitting module to pass sequentially through the beam expander and electron beam correction modules before bombarding the anode target, thereby generating radiation from the anode target. The beam expander module is positioned on the side of the electron beam emitting module closest to the anode target to pre-expand the electron beam before it enters the electron beam correction module, resulting in a larger lateral distribution range. The expanded electron beam can cover a larger effective correction area of ​​the electron beam correction module, allowing the module to more fully act on different lateral regions of the electron beam, thus improving its sensitivity and ability to correct beam current distribution, astigmatism, and beam spot morphology. The electron beam correction module, positioned on the side of the beam expander module closest to the anode target, can reshape and correct the pre-expanded electron beam, resulting in better beam current uniformity and transmission stability during subsequent focusing. The electron beam, after being corrected by the electron beam correction module, can bombard the anode target more stably and form a stable micro-focal spot on the anode target, thereby reducing the risk of focus drift and beam spot distortion, improving the stability of electron beam micro-focal spot formation, and improving the stability of X-ray output.

[0016] It should be understood that the description in this section is not intended to identify key or essential features of the embodiments of the present invention, nor is it intended to limit the scope of the invention. Other features of the invention will become readily apparent from the following description. Attached Figure Description

[0017] To more clearly illustrate the technical solutions in the embodiments of the present invention, the accompanying drawings used in the description of the embodiments will be briefly introduced below. Obviously, the accompanying drawings described below are only some embodiments of the present invention. For those skilled in the art, other drawings can be obtained based on these drawings without creative effort.

[0018] Figure 1 This is a schematic diagram of the structure of a radiation generating device provided in an embodiment of the present invention; Figure 2 This is a schematic diagram of another ray generating device provided in an embodiment of the present invention; Figure 3 This is a schematic diagram of the structure of an electron beam emission module provided in an embodiment of the present invention; Figure 4 This is a schematic diagram of the structure of a tungsten single crystal emission tip provided in an embodiment of the present invention. Detailed Implementation

[0019] To enable those skilled in the art to better understand the present invention, the technical solutions of the present invention will be clearly and completely described below with reference to the accompanying drawings of the embodiments of the present invention. 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 should fall within the scope of protection of the present invention.

[0020] It should be noted that the terms "first," "second," etc., in the specification, claims, and accompanying drawings of this invention are used to distinguish similar objects and are not necessarily used to describe a specific order or sequence. It should be understood that such data can be interchanged where appropriate so that the embodiments of the invention described herein can be implemented in orders other than those illustrated or described herein. Furthermore, the terms "comprising" and "having," and any variations thereof, are intended to cover non-exclusive inclusion; for example, a process, method, system, product, or apparatus that comprises a series of steps or units is not necessarily limited to those steps or units explicitly listed, but may include other steps or units not explicitly listed or inherent to such processes, methods, products, or apparatus.

[0021] Figure 1 This is a schematic diagram of the structure of a radiation generating device provided in an embodiment of the present invention. Figure 1 As shown, the radiation generating device includes: an electron beam emitting module 1, a beam expanding module 2, an electron beam correction module 3, and an anode target 4; along the first direction X, the electron beam emitting module 1, the beam expanding module 2, the electron beam correction module 3, and the anode target 4 are arranged sequentially; the electron beam emitting module 1 is used to emit an electron beam; the beam expanding module 2 is located on the side of the electron beam emitting module 1 closest to the anode target 4; the beam expanding module 2 is used to expand the electron beam; the electron beam correction module 3 is located on the side of the beam expanding module 2 closest to the anode target 4; the electron beam correction module 3 is used to shape the expanded electron beam; the electron beam shaped by the electron beam correction module 3 is used to bombard the anode target 4 to make the anode target 4 generate radiation.

[0022] Here, the first direction X can be understood as the direction in which the electron beam is transmitted from the electron beam emitting module 1 toward the anode target 4. The electron beam emitting module 1 is used to generate and emit the electron beam, the beam expander module 2 is used to expand the electron beam before it enters the electron beam correction module 3, and the electron beam correction module 3 is used to shape the expanded electron beam. The shaped electron beam is used to bombard the anode target 4 so that the anode target 4 produces rays.

[0023] Specifically, the electron beam emitting module 1 can serve as an electron source in the radiation generating device, used to emit an electron beam in the direction of the anode target 4. The electron beam emitted by the electron beam emitting module 1 can be transmitted along the first direction X under the action of an electric field, and arrives at the anode target 4 after passing through the beam expanding module 2 and the electron beam correction module 3 in sequence. For example, the electron beam emitting module 1 can be a field emission cathode, which can generate an electron beam with a small source size and high brightness. The anode target 4 can be a target material capable of generating radiation under electron beam bombardment, such as a metal target. When the high-speed electron beam bombards the anode target 4, the electrons in the electron beam interact with the atoms in the anode target 4, and the kinetic energy of the electrons is at least partially converted into radiation energy, thereby causing the anode target 4 to output radiation. For example, the radiation can be X-rays, which can be used for radiation imaging, non-destructive testing, micro-area inspection, structural inspection, or other inspection scenarios that require a radiation source.

[0024] The beam expander module 2 is located between the electron beam emission module 1 and the electron beam correction module 3. It is used to increase the beam diameter of the electron beam before it enters the electron beam correction module 3. The expanded electron beam has a larger lateral distribution range, covering the effective correction area of ​​the electron beam correction module 3. This allows the electron beam correction module 3 to more fully act on different lateral positions of the electron beam, improving its ability to adjust the beam current distribution, astigmatism, or beam spot morphology. After being shaped by the electron beam correction module 3, the expanded electron beam continues to propagate towards the anode target 4 and gradually refocuses, forming a stable microfocal point on the surface of the anode target 4.

[0025] The electron beam correction module 3 is located on the side of the beam expander module 2 closest to the anode target 4, and is used to shape the expanded electron beam. Shaping can be understood as correcting the beam current distribution, astigmatism, beam spot shape, or transmission direction of the electron beam, making the convergence state of the electron beam more consistent in different lateral directions, and allowing the electron beam to continue transmitting towards the anode target 4 and gradually refocus, forming a stable micro-focal point on the surface of the anode target 4. Because the electron beam is pre-expanded by the beam expander module 2 before entering the electron beam correction module 3, the electron beam correction module 3 has higher correction sensitivity and can more accurately correct problems such as astigmatism, skewness, or uneven beam current distribution, thereby improving the uniformity of the electron beam current distribution and the stability of the focal spot formed by the electron beam on the anode target 4. Optionally, the electron beam correction module 3 is an astigmatism reducer. The astigmatism reducer can differentiate the transmission state of the electron beam in different lateral directions by generating a correction electric field and / or a correction magnetic field to correct the lateral trajectory of the electron beam, making the convergence state of the electron beam more consistent in different directions. This improves the focusing quality of the electron beam, enabling the electron beam to form tiny focal spots more stably on the anode target 4.

[0026] The anode target 4 is located on the side of the electron beam correction module 3 closest to the radiation output side, and is used to receive the electron beam shaped by the electron beam correction module 3. After the shaped electron beam bombards the anode target 4, it can form a focal spot on the surface of the anode target 4 and cause the anode target 4 to produce radiation. Since the electron beam undergoes beam expansion and shaping processes before bombarding the anode target 4, the transmission state of the electron beam is more stable and the beam current distribution is more uniform. Therefore, it can reduce the risk of focal spot size increase, focal spot shape distortion, or focal spot position drift, which is beneficial to forming a stable small focal spot on the anode target 4.

[0027] It is understandable that by setting up a beam expander module 2 between the electron beam emission module 1 and the electron beam correction module 3, the electron beam is expanded before correction. The beam expander module 2 is not used to enlarge the final beam spot, but rather to create an appropriate pre-expanded beam state before the electron beam enters the electron beam correction module 3. This improves the effective correction range, sensitivity, and capability of the electron beam correction module 3, resulting in a more stable microfocus during subsequent focusing. The corrected electron beam can bombard the anode target 4 more stably, which is beneficial for improving the stability of the electron beam microfocus formation, reducing focus drift, and improving the stability of the radiation output. When the radiation is X-ray, it is beneficial for achieving stable microfocus X-ray output, thereby improving the resolution and stability of X-ray imaging, detection, or non-destructive testing.

[0028] In this embodiment, an electron beam emitting module 1, a beam expander module 2, an electron beam correction module 3, and an anode target 4 are arranged sequentially along the first direction X in the radiation generating device. This allows the electron beam emitted by the electron beam emitting module 1 to pass sequentially through the beam expander module 2 and the electron beam correction module 3 before bombarding the anode target 4, thereby generating radiation from the anode target 4. The beam expander module 2 is located on the side of the electron beam emitting module 1 closest to the anode target 4, enabling pre-expansion of the electron beam before it enters the electron beam correction module 3, resulting in a larger lateral distribution range. The expanded electron beam can cover a larger effective correction area of ​​the electron beam correction module 3, allowing the module to more fully act on different lateral regions of the electron beam, thus improving its sensitivity and ability to correct beam current distribution, astigmatism, and beam spot morphology. The electron beam correction module 3, located on the side of the beam expander module 2 closest to the anode target 4, can reshape and correct the pre-expanded electron beam, resulting in better beam current uniformity and transmission stability during subsequent focusing. The electron beam corrected by the electron beam correction module 3 can bombard the anode target 4 more stably and form a stable micro-focal spot on the anode target 4, thereby reducing the risk of focus drift and beam spot distortion, improving the stability of electron beam micro-focal spot formation, and improving the stability of X-ray output.

[0029] Optional, Figure 2 This is a schematic diagram of another ray generating device provided in an embodiment of the present invention. Figure 2 As shown, the radiation generating device further includes: an extraction electrode 5; the extraction electrode 5 is located between the electron beam emission module 1 and the beam expansion module 2; the extraction electrode 5 has a positive potential relative to the electron beam emission module 1; the extraction electrode 5 is used to extract an electron beam with a divergence angle less than or equal to a preset divergence angle, and to emit the electron beam with a divergence angle less than or equal to the preset divergence angle to the beam expansion module 2.

[0030] Among them, the extraction electrode 5 can serve as an electron beam extraction structure between the electron beam emission module 1 and the beam expansion module 2, and is used to extract, guide and preliminarily screen the electrons emitted by the electron beam emission module 1 so that the electron beam that meets the preset divergence angle requirements enters the beam expansion module 2.

[0031] Specifically, the extraction electrode 5 has a positive potential relative to the electron beam emission module 1. Since electrons are negatively charged, when the potential of the extraction electrode 5 is higher than that of the electron beam emission module 1, an extraction electric field can be formed between the extraction electrode 5 and the electron beam emission module 1, causing the electron beam to propagate along the first direction X toward the beam expansion module 2. Therefore, the extraction electrode 5 can improve the stability of electron beam extraction, allowing the electron beam to enter the subsequent beam expansion module 2 in a more stable initial state.

[0032] Furthermore, the extraction electrode 5 may have an extraction electrode aperture for the electron beam to pass through. The electron beam emitted by the electron beam emission module 1 may include electrons with large divergence angles. If these electrons directly enter the beam expansion module 2 and the electron beam correction module 3, it can easily lead to uneven distribution of the subsequent electron beam current, an increase in stray electrons, and a decrease in focal spot stability. By setting the aperture of the extraction electrode aperture, the distance between the extraction electrode 5 and the electron beam emission module 1, and the potential of the extraction electrode 5, the divergence angle of the electron beam that can pass through the extraction electrode aperture can be limited. This allows electron beams with divergence angles less than or equal to a preset divergence angle to pass through the extraction electrode 5 and enter the beam expansion module 2, while electron beams with large divergence angles are at least partially blocked or intercepted by the extraction electrode 5. Electron beams with large divergence angles are blocked or intercepted by the extraction electrode 2 at low energy levels, thereby reducing the thermal load of high-energy electrons on subsequent structures. The extraction electrode 5 can not only achieve electron beam extraction, but also complete the preliminary collimation and divergence angle screening of the electron beam before it enters the beam expansion module 2. This reduces the number of high divergence angle electrons entering the subsequent beam expansion module 2 and electron beam correction module 3, reduces the influence of stray electrons on the electron beam expansion, shaping and focusing process, improves the electron beam direction consistency and beam current stability, and is conducive to further improving the beam current density, focal spot stability and X-ray output stability of the electron beam on the anode target 4.

[0033] Optional, continue to refer to Figure 2 The beam expansion module 2 includes a deceleration electrode 21 and an anode electrode 22; the anode electrode 22 is located on the side of the deceleration electrode 21 close to the anode target 4; the deceleration electrode 21 has a negative potential relative to the extraction electrode 5, and the anode electrode 22 is grounded.

[0034] Specifically, along the transmission direction of the electron beam, the extraction electrode 5, the deceleration electrode 21, the anode electrode 22, and the electron beam correction module 3 are arranged in sequence, so that after the electron beam is extracted by the extraction electrode 5, it first enters the beam expansion region formed by the deceleration electrode 21 and the anode electrode 22, and then enters the electron beam correction module 3 for shaping.

[0035] The deceleration electrode 21 has a negative potential relative to the extraction electrode 5. Since electrons are negatively charged, when the electron beam is transmitted from the extraction electrode 5 to the deceleration electrode 21, the potential relationship between the deceleration electrode 21 and the extraction electrode 5 can decelerate the electron beam, reducing its axial velocity. After the axial velocity of the electron beam is reduced, its lateral divergence is relatively enhanced, which is beneficial for the electron beam to form an expanded diameter state before entering the electron beam correction module 3.

[0036] The anode electrode 22 is located on the side of the deceleration electrode 21 closest to the anode target 4, and is grounded. The anode electrode 22 can serve as a reference electrode or boundary electrode in the beam expander module 2, forming a stable electrostatic field region with the deceleration electrode 21. This allows the electron beam correction module 3 to have a larger effective correction range and higher correction capability. Through the relative positional and potential relationships between the deceleration electrode 21 and the anode electrode 22, an electrostatic lens field can be formed between them. This electrostatic lens field can adjust the electron beam's transmission trajectory and lateral dimensions, ensuring the electron beam forms an appropriate diameter expansion state before entering the electron beam correction module 3. This allows the electron beam to cover the effective correction area of ​​the electron beam correction module 3, thereby improving the sensitivity of the electron beam correction module 3 in adjusting the electron beam current distribution, astigmatism, and beam spot morphology, and further enhancing the stability of the micro-focus formation and radiation output of the electron beam on the anode target 4.

[0037] Optional, continue to refer to Figure 2 Along the first direction X, the distance between the deceleration electrode 21 and the anode electrode 22 is L1, the distance between the deceleration electrode 21 and the electron beam emission module 1 is L2, and the distance between the deceleration electrode 21 and the anode target 4 is L3; where L1 < L2; L2 < L3.

[0038] Understandably, a relatively concentrated electrostatic field distribution can be formed between the deceleration electrode 21 and the anode electrode 22. This electrostatic field distribution enables the electron beam to expand before entering the electron beam correction module 3, thereby improving the sensitivity of the electron beam correction module 3 in adjusting the electron beam current distribution, astigmatism, and beam spot morphology. Simultaneously, the electrostatic lens formed by the deceleration electrode 21 and the anode electrode 22 not only achieves pre-expansion of the electron beam but also regulates its subsequent transmission and focusing. After expansion, the electron beam continues to propagate towards the anode target 4 and gradually focuses under the combined action of the electrostatic lens field and the subsequent electron beam correction module 3. During this process, the electron beam correction module 3 can perform astigmatism correction and beam spot shaping on the expanded electron beam, ensuring good beam current uniformity and optical axis stability during focusing.

[0039] Therefore, by limiting L1 < L2, the electrostatic lens region formed by the deceleration electrode 21 and the anode electrode 22 can be positioned closer to the electron beam correction module 3. This allows the electron beam to undergo appropriate diameter expansion before entering the electron beam correction module 3, resulting in a larger lateral beam diameter. This improves the effective correction range and capability of the electron beam correction module 3, and allows the electron beam to be stably focused under the correction effect of the electron beam correction module 3. Compared to the scheme where the electron beam enters the correction module directly without beam expansion, this improves correction accuracy, reduces astigmatism, beam spot distortion, and focus drift risks, thereby improving the stability of microfocus formation and X-ray output on the anode target 4.

[0040] Furthermore, by limiting L2 to L3, a longer electron beam transmission distance is reserved between the deceleration electrode 21 and the anode target 4. This allows the electron beam, after being expanded in the electrostatic lens region formed by the deceleration electrode 21 and the anode electrode 22, to be fully corrected by the electron beam correction module 3 before reaching the anode target 4. By setting the distance between the deceleration electrode 21 and the anode target 4 to be greater than the distance between the deceleration electrode 21 and the electron beam emission module 1, sufficient correction space is provided for the expanded electron beam. This allows the electron beam correction module 3 to more fully correct astigmatism, uneven beam distribution, and beam spot distortion, thereby improving the correction capability and accuracy of the electron beam correction module 3. Consequently, the corrected electron beam can be more stably focused and bombard the anode target 4, which helps reduce the risk of focus drift and focal spot distortion, and improves the stability of microfocus formation and radiation output.

[0041] Optional, continue to refer to Figure 2 The extraction electrode 5 has an extraction electrode hole 51 through which the electron beam passes; the diameter of the extraction electrode hole 51 is d1; the deceleration electrode 21 has a deceleration electrode hole 211 through which the electron beam passes; the diameter of the deceleration electrode hole 211 is d2; the anode electrode 22 has an anode electrode hole 221 through which the electron beam passes; wherein, d1 < d2 / 2.

[0042] The extraction electrode hole 51, the deceleration electrode hole 211 and the anode electrode hole 221 can be arranged opposite each other along the first direction X so that the electron beam can pass through the extraction electrode hole 51, the deceleration electrode hole 211 and the anode electrode hole 221 in sequence and continue to be transmitted toward the electron beam correction module 3 and the anode target 4.

[0043] Specifically, by setting d1 < d2 / 2, the extraction electrode aperture 51 can limit the aperture of the electron beam before it enters the beam expander module 2. It is understood that the electron beam emitted by the electron beam emission module 1 may contain electrons with large divergence angles. When these electrons propagate in a direction deviating from the first direction X, they are unlikely to pass through the smaller aperture of the extraction electrode aperture 51 and will therefore be blocked or intercepted by the extraction electrode 5. Conversely, electrons with smaller divergence angles and closer to the electron beam transmission axis can pass through the extraction electrode aperture 51 and enter the deceleration electrode aperture 211.

[0044] Through the above configuration, the extraction electrode aperture 51 can perform preliminary collimation and divergence angle screening of the electron beam, allowing electron beams with divergence angles less than or equal to the preset value to enter the beam expansion module 2. This reduces the number of high-divergence-angle electrons entering the subsequent deceleration electrode 21, anode electrode 22, and electron beam correction module 3. This reduces the interference of stray electrons on the subsequent electron beam expansion, shaping, and focusing processes, improves the directional consistency and beam stability of the electron beam entering the beam expansion module 2, and simultaneously reduces the thermal load on the anode electrode 22 caused by high-energy electron beams with large divergence angles.

[0045] Furthermore, since the aperture d2 of the deceleration electrode aperture 211 is larger than the aperture d1 of the extraction electrode aperture 51, the deceleration electrode aperture 211 can provide a larger passage space for the electron beam after passing through the extraction electrode aperture 51. When the electron beam expands under the influence of the potential relationship between the deceleration electrode 21 and the extraction electrode 5, and in the electrostatic lens region formed by the deceleration electrode 21 and the anode electrode 22, the larger deceleration electrode aperture 211 can reduce the risk of the effective electron beam being intercepted by the deceleration electrode 21, enabling the electron beam to form the expected diameter expansion state within the beam expansion module 2 and smoothly enter the subsequent electron beam correction module 3.

[0046] Optional, continue to refer to Figure 2 The radiation generating device further includes: an emitter alignment mechanism 11, an extractor alignment mechanism 52, and an anode alignment mechanism 222; the emitter alignment mechanism 11 is connected to the electron beam emitting module 1, the extractor alignment mechanism 52 is connected to the extractor electrode 5, and the anode alignment mechanism 222 is connected to the anode electrode 22; the emitter alignment mechanism 11 is used to adjust the position of the electron beam emitting module 1 along the second direction Y, the extractor alignment mechanism 52 is used to adjust the position of the extractor electrode 5 along the second direction Y, and the anode alignment mechanism 222 is used to adjust the position of the anode electrode 22 along the second direction Y, so that the transmission axis of the electron beam emitted by the electron beam emitting module 1, the extractor electrode hole 51, the deceleration electrode hole 211, and the anode electrode hole 221 are aligned along the first direction X; wherein, the second direction Y intersects with the first direction X.

[0047] The emitter alignment mechanism 11, the extractor alignment mechanism 52, and the anode alignment mechanism 222 together constitute a multi-level coupled alignment structure, which is used to adjust the positions of the electron beam emission module 1, the extractor electrode 5, and the anode electrode 22 respectively, thereby improving the coaxiality between the electron beam transmission axis and each electrode hole.

[0048] Specifically, the emitter alignment mechanism 11 can be connected to the mounting base, support, or housing of the electron beam emitting module 1, and is used to adjust the position of the electron beam emitting module 1 along the second direction so that the transmission axis of the electron beam emitted by the electron beam emitting module 1 is aligned with the subsequent extraction electrode hole 51, deceleration electrode hole 211, and anode electrode hole 221. The extraction electrode alignment mechanism 52 can be connected to the extraction electrode 5 or the electrode holder for fixing the extraction electrode 5, and is used to adjust the position of the extraction electrode 5 along the second direction. When the extraction electrode hole 51 is offset relative to the electron beam transmission axis, the electron beam may be subjected to an asymmetric electric field, causing the electron beam to deflect or have uneven beam distribution when entering the deceleration electrode 21. By adjusting the position of the extraction electrode 5 through the extraction electrode alignment mechanism 52, the extraction electrode hole 51 can be aligned with the electron beam transmission axis, thereby reducing the offset of the electron beam before entering the beam expander module 2. The anode alignment mechanism 222 can be connected to the anode electrode 22 or an electrode support structure for fixing the anode electrode 22. It is used to adjust the position of the anode electrode 22 along the second direction to improve the coaxiality of the anode electrode hole 221 with the electron beam transmission axis and reduce the risk of electron beam focus drift. The second direction Y can be a transverse direction perpendicular to the first direction X.

[0049] For example, the emitter alignment mechanism 11, the extractor alignment mechanism 52, and the anode alignment mechanism 222 can be mechanical fine-tuning mechanisms, motor-driven slides, piezoelectric ceramic drive mechanisms, flexible hinge adjustment mechanisms, threaded adjustment mechanisms, or other structures capable of achieving micro-displacement adjustment.

[0050] In addition, the radiation generating device may also include a deceleration electrode alignment mechanism connected to the deceleration electrode 21, which is used to adjust the position of the deceleration electrode 21 along the second direction so that the deceleration electrode hole 211 is further aligned with the extraction electrode hole 51 and the anode electrode hole 221, thereby reducing the optical axis deviation between the deceleration electrode 21 and the extraction electrode 5 and the anode electrode 22, and thus improving the symmetry of the electrostatic lens field formed by the deceleration electrode 21 and the anode electrode 22.

[0051] The multi-stage coupling and alignment structure described above enables multi-stage adjustment and coupling alignment of the electron beam transmission path. This reduces the transmission offset of the electron beam in the deceleration region and improves the positional stability of the electron beam when it enters the electron beam correction module 3. Simultaneously, it reduces the drift of the focal spot on the surface of the anode target 4, improves the stability of electron beam microfocus formation, and contributes to improved X-ray output stability and imaging quality.

[0052] It should be noted that the radiation generating device may also include a vacuum cavity, in which the electron beam emitting module 1, extraction electrode 5, beam expander module 2, electron beam correction module 3, and anode target 4 are all disposed. This reduces collisions between the electron beam and gas molecules during transmission, lowers the risk of electron beam scattering, energy loss, and beam instability, and improves the stability of electron beam transmission and radiation output. At least part of the multi-stage coupling alignment structure can be disposed outside the vacuum cavity. For example, the drive, adjustment, or operation parts of the emitter alignment mechanism 11, extraction electrode alignment mechanism 52, anode alignment mechanism 222, and / or deceleration electrode alignment mechanism can be disposed outside the vacuum cavity and connected to the corresponding electron beam emitting module 1, extraction electrode 5, anode electrode 22, and / or deceleration electrode 21 inside the vacuum cavity via transmission rods, flexible connectors, sealed bellows, or vacuum feedthrough structures. This allows for fine-tuning of the positions of components inside the vacuum cavity from outside without disrupting the vacuum environment, thereby improving the alignment accuracy between the electron beam transmission axis and each electrode aperture and reducing the risk of focal spot drift.

[0053] Optional, Figure 3 This is a schematic diagram of the structure of an electron beam emitting module provided in an embodiment of the present invention. Figure 4 This is a schematic diagram of the structure of a tungsten single-crystal emission tip provided in an embodiment of the present invention. (Refer to reference...) Figure 2 , Figure 3 and Figure 4 As shown, the electron beam emission module 1 includes a tungsten single crystal emission tip 01 and a suppression electrode 02 disposed around the tungsten single crystal emission tip 01; a zirconium oxide layer 03 is disposed on the surface of the tungsten single crystal emission tip 01; the tungsten single crystal emission tip 01 is used to generate an electron beam; the suppression electrode 02 includes an emission opening 04 for the electron beam to pass through, and the suppression electrode 02 is used to suppress the influence of the external electric field and / or external magnetic field of the electron beam emission module 1 on the electron beam.

[0054] The tungsten single crystal emitting tip 01 is used to generate an electron beam, and the suppressor 02 includes an exit opening 04 for the electron beam to pass through. The electron beam emitted by the tungsten single crystal emitting tip 01 can be emitted through the exit opening 04 and transmitted along the first direction toward the extraction electrode 5, the beam expanding module 2, the electron beam correction module 3 and the anode target 4.

[0055] Specifically, the tungsten single-crystal emitting tip 01 can be connected to the filament 05. The filament 05 can support the tungsten single-crystal emitting tip 01 and can also be used to heat the tungsten single-crystal emitting tip 01 so that it meets the working conditions required for electron emission. The tip region of the tungsten single-crystal emitting tip 01 has a small radius of curvature, which can form a strong local electric field intensity under the action of an electric field, thereby facilitating the emission of electrons from the tungsten single-crystal emitting tip 01.

[0056] A zirconium oxide layer 03 can be deposited on the surface of the tungsten single crystal emission tip 01. The zirconium oxide layer 03, in conjunction with the tungsten single crystal emission tip 01, forms a Schottky field emission structure to improve the electron emission characteristics of the tungsten single crystal emission tip 01, enabling the electron beam emission module 1 to generate an electron beam with a small source size, high brightness, and good stability. This facilitates subsequent beam expansion, shaping, and focusing control via the beam expansion module 2 and the electron beam correction module 3, and also helps to form a stable, small focal spot on the anode target 4.

[0057] The suppression electrode 02 can be understood as a conductive shielding electrode placed outside the tungsten single crystal emitting tip 01, ensuring that the electron beam is mainly emitted from the tip region of the tungsten single crystal emitting tip 01 and exits through the exit opening 04. By setting the suppression electrode 02, stray electron emission from areas outside the tungsten single crystal emitting tip 01, the filament 05, or other supporting structures can be suppressed, reducing the entry of non-target electrons into the subsequent electron optics system. Simultaneously, it can reduce the interference of the external electric field and / or external magnetic field of the electron beam emitting module 1 on the emission electric field near the tungsten single crystal emitting tip 01, making the initial emission direction and initial beam current state of the electron beam more stable. This reduces the risk of electron beam deviation during subsequent extraction, beam expansion, and correction processes, improves electron beam transmission stability, and is beneficial for improving the stability of microfocus formation on the anode target 4 and the stability of X-ray output.

[0058] It should be noted that the electron beam emission module 1 can also adopt a thermal field emission structure or other electron source structure capable of generating an electron beam. Provided that the electron beam emission module 1 can generate an electron beam that is transmitted toward the anode target 4, and can cooperate with the subsequent beam expansion module 2 and electron beam correction module 3 to realize electron beam expansion, shaping and focusing control, the structure of the electron beam emission module 1 is not specifically limited in this embodiment of the invention.

[0059] Optional, continue to refer to Figure 2 Along the first direction, the distance between the tungsten single crystal emitting tip 01 and the extraction electrode 5 is L4; wherein, L4≥3mm.

[0060] Understandably, the distance between the tungsten single-crystal emitting tip 01 and the extraction electrode 5 affects the extraction electric field distribution and the initial divergence state of the electron beam. When the distance between the tungsten single-crystal emitting tip 01 and the extraction electrode 5 is too small, the local electric field near the tungsten single-crystal emitting tip 01 may become too concentrated, easily leading to instability in the electron beam extraction process and a large initial divergence angle of the electron beam after extraction. Electrons with large divergence angles, after entering the subsequent beam expanding module 2 and electron beam correction module 3, are prone to causing problems such as uneven beam distribution, increased stray electrons, and unstable focal spot morphology.

[0061] By ensuring L4 ≥ 3 mm, a suitable distance can be maintained between the tungsten single crystal emission tip 01 and the extraction electrode 5, creating a relatively stable extraction electric field. This facilitates stable electron beam extraction and reduces the risk of excessive divergence during the extraction stage. L4 ≥ 3 mm can also be coordinated with the aperture of the extraction electrode hole 51 to limit the divergence angle of the electron beam. Electrons with larger divergence angles are more easily intercepted by the extraction electrode 5, while electrons with smaller divergence angles and closer to the electron beam transmission axis can pass through the extraction electrode hole 51 into the beam expansion module 2. This reduces the number of high-divergence-angle electrons entering the subsequent structure, improves the consistency of the electron beam direction and beam stability entering the beam expansion module 2, and allows the electron beam correction module 3 to more accurately shape the electron beam. This improves the stability of the micro-focus formation on the anode target 4, thereby increasing X-ray brightness and X-ray output stability.

[0062] Based on the same inventive concept, this invention also provides a radiation tube, which includes the radiation generating device described in the above embodiments.

[0063] The X-ray tube can be used to generate radiation, for example, X-rays. Specifically, the X-ray tube can be applied in X-ray imaging equipment, industrial non-destructive testing equipment, micro-focus X-ray inspection equipment, X-ray microscopy imaging equipment, CT inspection equipment, or semiconductor device internal structure inspection equipment. The X-rays generated by the X-ray tube can be used to irradiate the object to be inspected, and the X-ray signals transmitted through the object or acted upon by the object are received by a detector, thereby achieving imaging, detection, or analysis.

[0064] Therefore, the X-ray tube provided in this embodiment has the structure and operation of the X-ray generating device of the above embodiment, and can achieve the effect of the X-ray generating device of the above embodiment. The similarities can be referred to the above description, and will not be repeated here.

[0065] It should be understood that the various forms of processes shown above can be used to reorder, add, or delete steps. For example, the steps described in this invention can be executed in parallel, sequentially, or in different orders, as long as the desired result of the technical solution disclosed in this invention can be achieved, and this is not limited herein.

[0066] The specific embodiments described above do not constitute a limitation on the scope of protection of this invention. Those skilled in the art should understand that various modifications, combinations, sub-combinations, and substitutions can be made according to design requirements and other factors. Any modifications, equivalent substitutions, and improvements made within the spirit and principles of this invention should be included within the scope of protection of this invention.

Claims

1. A radiation generating device, characterized in that, include: Electron beam emission module, beam expander module, electron beam correction module, and anode target; Along the first direction, the electron beam emitting module, the beam expanding module, the electron beam correction module, and the anode target are arranged in sequence; The electron beam emitting module is used to emit an electron beam; The beam expanding module is located on the side of the electron beam emitting module closer to the anode target; the beam expanding module is used to expand the electron beam. The electron beam correction module is located on the side of the beam expander module closer to the anode target; the electron beam correction module is used to shape the expanded electron beam. The electron beam, after being shaped by the electron beam correction module, is used to bombard the anode target to cause the anode target to generate radiation.

2. The radiation generating device according to claim 1, characterized in that, Also includes: Extraction electrode; The extraction electrode is located between the electron beam emission module and the beam expander module; The extraction electrode has a positive potential relative to the electron beam emission module; The extraction electrode is used to extract the electron beam with a divergence angle less than or equal to the preset divergence angle, and to emit the electron beam with a divergence angle less than or equal to the preset divergence angle to the beam expander module.

3. The radiation generating apparatus according to claim 2, characterized in that, The beam expanding module includes a deceleration electrode and an anode electrode; The anode electrode is located on the side of the deceleration electrode closer to the anode target; The deceleration electrode has a negative potential relative to the extraction electrode, and the anode electrode is grounded.

4. The radiation generating apparatus according to claim 3, characterized in that, Along the first direction, the distance between the deceleration electrode and the anode electrode is L1, the distance between the deceleration electrode and the electron beam emission module is L2, and the distance between the deceleration electrode and the anode target is L3; Where L1 < L2; L2 < L3.

5. The radiation generating apparatus according to claim 3, characterized in that, The extraction electrode has an extraction electrode hole through which the electron beam passes; the diameter of the extraction electrode hole is d1. The deceleration electrode has a deceleration electrode hole through which the electron beam passes; the diameter of the deceleration electrode hole is d2; The anode electrode has an anode electrode aperture through which the electron beam passes; Where d1 < d2 / 2.

6. The radiation generating apparatus according to claim 5, characterized in that, Also includes: Emitter alignment mechanism, extractor alignment mechanism, and anode alignment mechanism; The emitter alignment mechanism is connected to the electron beam emission module, the extraction electrode alignment mechanism is connected to the extraction electrode, and the anode alignment mechanism is connected to the anode electrode. The emitter alignment mechanism is used to adjust the position of the electron beam emitting module along the second direction, the extraction electrode alignment mechanism is used to adjust the position of the extraction electrode along the second direction, and the anode alignment mechanism is used to adjust the position of the anode electrode along the second direction, so that the transmission axis of the electron beam emitted by the electron beam emitting module, the extraction electrode hole, the deceleration electrode hole, and the anode electrode hole are aligned along the first direction; The second direction intersects with the first direction.

7. The radiation generating apparatus according to claim 2, characterized in that, The electron beam emission module includes a tungsten single crystal emission tip and a suppression electrode disposed around the tungsten single crystal emission tip; A zirconium oxide layer is disposed on the surface of the tungsten single crystal emission tip; the tungsten single crystal emission tip is used to generate the electron beam. The suppression electrode includes an exit opening through which the electron beam passes, and the suppression electrode is used to suppress the influence of the external electric field and / or external magnetic field of the electron beam emission module on the electron beam.

8. The radiation generating apparatus according to claim 7, characterized in that, Along the first direction, the distance between the tungsten single crystal emitting tip and the extraction electrode is L4; Where L4 ≥ 3mm.

9. The radiation generating apparatus according to claim 1, characterized in that, The electron beam correction module is an astigmatism reducer.

10. A ray tube, characterized in that, include: The radiation generating apparatus according to any one of claims 1-9.

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