X-ray inspection device and inspection method thereof

Abstract

An X-ray inspection apparatus is disclosed. The apparatus includes: an anode on which a target is disposed; the cathode is used for emitting an electron beam to a target; a gate electrode positioned between the cathode and the anode and facing the cathode side; a power supply unit for applying a voltage to each of the cathode, the gate, and the anode; and a control unit. The control unit controls the power supply unit such that a cathode voltage of a preset amplitude is applied to the cathode and an anode voltage of a preset amplitude is applied to the anode, and controls the power supply unit such that a gate voltage within a preset voltage range is selectively applied to the gate, thereby adjusting the amount of the electron beam.

Description

Technical Field

[0001] This disclosure relates to an X-ray inspection apparatus and method thereof that perform inspections by controlling the voltage of a grid in an X-ray tube. Background Technology

[0002] X-ray inspection technology is used as one of the methods to identify the internal features of an object without damaging it. X-ray inspection equipment can be used to inspect a variety of objects, such as the human body and secondary batteries.

[0003] An X-ray inspection device is a device that inspects an object by emitting an electron beam toward it and using the X-rays emitted from the target. X-ray inspection devices generate X-rays using an X-ray tube. An X-ray tube typically includes components such as a heater, cathode, grid, and anode. The target can be placed on the anode, and the electron beam emitted from the cathode can be projected toward the anode through the grid and collide with the target.

[0004] For such operation, a high voltage of approximately 100 kV is applied to the anode. There are technical limitations to controlling this high voltage in short-interval switching. Furthermore, unexpected discharges may occur when controlling the switching of each of the heater, cathode, grid, and anode, or the vacuum within the X-ray tube may be adversely affected.

[0005] As a result, conventional X-ray examination equipment cannot turn the electron beam on or off, and therefore cannot fine-tune the X-ray emission. Consequently, radiation exposure to the imaging target or user cannot be reduced.

[0006] Therefore, in order to solve the above problems, the purpose of this disclosure is to provide an X-ray inspection apparatus and method that can perform inspections while precisely adjusting X-ray emission. Summary of the Invention

[0007] Solution to the problem According to embodiments of the present disclosure, an X-ray inspection apparatus is provided, comprising: an anode on which a target is mounted; a cathode for emitting an electron beam toward the target; a grid located between the cathode and the anode and closer to the cathode; a power supply unit configured to apply voltages to the cathode, the grid, and the anode, respectively; and a control unit configured to control the power supply unit to apply a cathode voltage of a predetermined amplitude to the cathode and an anode voltage of a predetermined amplitude, and to control the power supply unit to adjust the amount of electron beam emitted from the cathode and transferred toward the anode by selectively applying a grid voltage within a predetermined voltage range to the grid.

[0008] The control unit can be configured to adjust the amplitude of the gate voltage within a voltage range between a first voltage for blocking the electron beam and a second voltage for allowing the electron beam to pass through. The first voltage may be a voltage having the same polarity as the cathode voltage and is set to block the amplitude of the electron beam emitted from the cathode by the repulsive force generated by the gate, and the second voltage may be a voltage having the same polarity as the cathode voltage and is set to focus the amplitude of the electron beam emitted from the cathode through the gate by the repulsive force generated by the gate.

[0009] The apparatus may further include: a conveyor belt for conveying an object to be inspected, wherein the control unit may be configured to, when the object to be inspected is conveyed by the conveyor belt to an inspection position, alternately adjust the gate voltage to a first voltage and a second voltage during a segment in which the object to be inspected passes through the inspection position, while the cathode is being applied to the cathode voltage and the anode is being applied to the anode voltage.

[0010] The control unit can be configured to control the power supply unit based on the respiratory cycle of the human body, which is the object to be inspected, to alternately adjust the gate voltage within a predetermined voltage range.

[0011] The power supply unit may include: a first power supply connected to the cathode; a second power supply connected to a node between the first power supply and the gate; and a third power supply connected to the anode, wherein the second power supply may be a power supply for providing a variable voltage within a predetermined voltage range, and the gate voltage may be a voltage having an amplitude obtained by adding the voltage of the first power supply and the voltage of the second power supply.

[0012] According to embodiments of the present disclosure, an inspection method for an X-ray inspection apparatus is provided, the method comprising: applying a predetermined amount of anode voltage and a predetermined amount of cathode voltage to an anode and a cathode, respectively; and adjusting the amount of an electron beam emitted from a cathode and transferred toward an anode by selectively applying a gate voltage within a predetermined voltage range to a gate, the gate being located between the cathode and the anode and closer to the cathode.

[0013] The adjustment of the amount of electron beam may include adjusting the amplitude of the gate voltage within a voltage range between a first voltage for blocking the electron beam and a second voltage for allowing the electron beam to pass through. The first voltage may be a voltage having the same polarity as the cathode voltage and is set to be able to block the amplitude of the electron beam emitted from the cathode by the repulsive force generated by the gate, and the second voltage may be a voltage having the same polarity as the cathode voltage and is set to be the amplitude of the electron beam emitted from the cathode that is focused by the repulsive force generated by the gate and passes through the gate.

[0014] The adjustment of the amount of electron beam may include: when the object to be inspected is transported by the conveyor belt to the inspection position, with the cathode being subjected to a cathode voltage and the anode being subjected to an anode voltage, the gate voltage is alternately adjusted to a first voltage and a second voltage during the segment during which the object to be inspected passes through the inspection position, while the object to be inspected is being transported by the conveyor belt to the inspection position.

[0015] The amount of electron beam can be adjusted by alternately adjusting the gate voltage within a predetermined voltage range based on the respiratory cycle of the human body, which is the object to be examined. Attached Figure Description

[0016] Figure 1 This is a view showing an example of the exterior of an X-ray tube used in an X-ray examination apparatus according to an embodiment of the present disclosure.

[0017] Figure 2 This is a view showing the configuration of an X-ray inspection apparatus according to an embodiment of the present disclosure.

[0018] Figure 3 and Figure 4 This is a view illustrating the operation of an X-ray inspection apparatus according to an embodiment of the present disclosure.

[0019] Figure 5 This is a view showing a detailed configuration of a power supply unit used in an X-ray inspection apparatus according to an embodiment of the present disclosure.

[0020] Figure 6 This is a view showing an example of the exterior of an X-ray inspection apparatus according to an embodiment of the present disclosure.

[0021] Figures 7 to 9 This is a view illustrating the control operation of an X-ray inspection apparatus according to an embodiment of the present disclosure.

[0022] Figure 10 This is a flowchart illustrating an inspection method according to an embodiment of the present disclosure. Detailed Implementation

[0023] In the following text, the terminology used in this disclosure will be briefly described first, and then the disclosure will be described in detail.

[0024] In consideration of the functions described herein, the terminology used herein has been selected as much as possible from currently widely used, general terms. However, terms may vary depending on the intent of those skilled in the art, precedents, the emergence of new technologies, and other factors. Furthermore, in certain cases, terms may be arbitrarily chosen by the applicant. In such cases, the meanings of these terms will be described in detail in the corresponding descriptions of this disclosure. Accordingly, the terms used in this disclosure should be defined based on their meaning and throughout the content of this disclosure, rather than on their simple names.

[0025] For example, the terms "first" and "second" can be used to describe various components. However, components should not be interpreted as being limited by these terms. These terms are only used to distinguish one component from another.

[0026] Unless the context clearly indicates otherwise, singular expressions include plural expressions. In this application, terms such as “comprising” or “configured” are intended to indicate the presence of features, numbers, steps, actions, components, parts or combinations thereof described herein, and should be understood to not exclude the presence or addition of one or more other features, numbers, steps, actions, components, parts or combinations thereof.

[0027] For example, the expression "at least one of A or B" should be understood as indicating either "A", "B", or "A and B".

[0028] In this disclosure, a "module" or "unit" can perform at least one function or operation and can be implemented as hardware, software, or a combination of hardware and software. Furthermore, in addition to "modules" or "units" that need to be implemented as specific hardware, multiple "modules" or multiple "units" can be integrated into at least one module and implemented as one or more processors (not shown).

[0029] In the following, embodiments of the present disclosure will be described in detail with reference to the accompanying drawings to allow those skilled in the art to readily implement the disclosure. However, the present disclosure may be implemented in various different forms and is not limited to the embodiments described herein. Furthermore, in the drawings, portions unrelated to the description have been omitted for clarity, and the same reference numerals are used for the same parts throughout the specification.

[0030] One or more embodiments of the present disclosure will be described in more detail below with reference to the accompanying drawings.

[0031] Figure 1 This is a view showing an example of the exterior of an X-ray tube used in an X-ray examination apparatus according to an embodiment of the present disclosure. Reference Figure 1 The X-ray tube 50 may include an electron generating unit 51 and a vacuum chamber 52. A heater, cathode, and grid may be disposed within the electron generating unit 51, and an anode may be disposed within the vacuum chamber 52. A target may be mounted on the anode.

[0032] Multiple electrodes 54 connected to internal components can be exposed on one side of the electron generating unit 51. Each of the electrodes can be connected to a power supply unit, which can provide an electrical signal to each of the electrodes 54 according to the control of the processor. When voltages are applied to the heater, cathode, grid, and anode respectively through the electrodes 54, the cathode can emit an electron beam, and the emitted electron beam can pass through the grid and be projected toward a target disposed on the anode within the vacuum chamber 52. The electron beam colliding with the target can generate X-rays, and the generated X-rays can be emitted through the transmission window 53.

[0033] With predetermined voltages applied to the heater, cathode, and anode, the X-ray inspection apparatus can regulate the amount of electron beam transferred from the cathode to the anode by adjusting the voltage applied to the grid. When the grid voltage is set to a specific value, the electron beam may not pass through the grid. Therefore, X-ray generation can be blocked while maintaining the voltages applied to components such as the cathode, anode, and heater.

[0034] Figure 2 This is a view illustrating the configuration of an X-ray inspection apparatus according to an embodiment of the present disclosure. Reference Figure 2 The X-ray inspection device 100 may include a cathode 110, a grid 120, an anode 130, a heater 140, a power supply unit 150, and a control unit 160. Figure 2 The diagram shows a cathode 110, a grid 120, an anode 130, and a heater 140 disposed within an X-ray tube 50, and a power supply unit 150 and a control unit 160 disposed outside the X-ray tube 50. This is merely an example, and at least one of the power supply unit 150 and the control unit 160 may be included together within the X-ray tube 50.

[0035] Target 131 can be mounted on anode 130. Detailed descriptions of the placement location, placement form, type, etc. of target 131 are omitted.

[0036] The cathode 110 is a component used to emit an electron beam toward the anode 130.

[0037] The gate 120 may be disposed between the cathode 110 and the anode 130. Specifically, the gate 120 may be disposed closer to the cathode 110 with respect to the midpoint between the cathode 110 and the anode 130.

[0038] The power supply unit 150 is a component used to provide electrical signals to various other components, such as the cathode 110, the gate 120, the anode 130, and the heater 140.

[0039] The control unit 160 is a component used to control the operation of various components included in the X-ray inspection apparatus 100. As an example, the control unit 160 can control the operation of the power supply unit 150 and can apply voltages of appropriate amplitudes to components such as the cathode 110, grid 120, anode 130, and heater 140.

[0040] The control unit 160 can be implemented in various forms, such as a central processing unit (CPU), graphics processing unit (GPU), accelerated processing unit (APU), multi-core integrated circuit (MIC), digital signal processor (DSP), neural processing unit (NPU), and other control logic. Although Figure 2 Only one control unit 160 is shown, but control unit 160 can also be implemented as multiple processors. Furthermore, although... Figure 2 The memory is not shown, but may further include at least one memory that is implemented separately from or integrated into the control unit 160.

[0041] The control unit 160 can control the power supply unit 150 to apply a predetermined amplitude cathode voltage to the cathode 110 and a predetermined amplitude anode voltage to the anode 130. Furthermore, the control unit 160 can control the power supply unit 150 to apply a voltage of appropriate amplitude to the heater 140. When voltage is applied to the heater 140 to heat the cathode 110, and voltage is applied to both the cathode 110 and the anode 130, an electron beam can be emitted from the cathode 110.

[0042] Control unit 160 can control power supply unit 150 to selectively apply a gate voltage within a predetermined voltage range to gate 120. The amount of electron beam emitted from cathode 110 and transferred toward anode 130 can be adjusted according to the change in gate voltage. The range of gate voltage can be set differently depending on the experiment. Specifically, when a first voltage and a second voltage are determined, wherein the amplitude of the first voltage allows it to block the electron beam, and the amplitude of the second voltage allows it to properly focus the electron beam and allow it to pass through the gate, switching to either the first voltage or the second voltage can be selectively performed. Alternatively, control unit 160 can select an amplitude within a range equal to or greater than the first voltage and equal to or less than the second voltage, and can control voltage unit 150 to provide a gate voltage with the selected amplitude.

[0043] The first voltage may be a voltage with the same polarity as the cathode voltage applied to the cathode 110, and the first voltage is set to the amplitude at which the electron beam emitted from the cathode 110 can be blocked by the repulsive force generated by the gate 120.

[0044] The second voltage can be a voltage with the same polarity as the cathode voltage, and the second voltage is set to be the amplitude of the electron beam emitted from the cathode 110 being focused by the repulsive force generated by the gate 120 and passing through the gate 120.

[0045] The amplitudes of the first and second voltages can be set differently depending on various factors (e.g., cathode voltage, anode voltage, and distance). Typically, when the cathode voltage is high, the gate voltage can also be set high.

[0046] For example, assuming the cathode voltage for emitting an electron beam current of 500 μA is -1000V, the electron beam current can be 500 μA when the gate voltage is -1100V. And assuming the cathode voltage is -2000V, the electron beam current can be 500 μA when the gate voltage is -2200V.

[0047] Accordingly, when the electron beam current is 0 μA, the gate voltage can be applied by exceeding the threshold voltage, rather than setting the gate voltage to the threshold voltage. For example, when the cathode voltage is -1000 V and the gate voltage needs to be at least -1250 V to make the electron beam current 0 μA (off), the first voltage can be set to a value with a margin relative to the threshold voltage (e.g., -1300 V, -1400 V, or -1500 V).

[0048] The voltage difference between the cathode voltage and the gate voltage can be achieved in various ways. For example, assuming a cathode voltage of -500 V, the electron beam current can be 500 μA when the gate voltage is approximately -530 V, and assuming a cathode voltage of -500 V, the electron beam current can be 0 μA when the gate voltage is approximately -800 V. If the gate voltage is implemented as a floating voltage, pulse control can be performed by alternately controlling a second power supply 152 connected to the gate voltage to -30 V or -300 V, thereby blocking the electron beam or allowing the electron beam to pass through the gate at 500 μA. As an example, the difference between the cathode voltage and the gate voltage that makes the electron beam current 0 μA can be approximately 200 V to 400 V, depending on the cathode voltage, but this difference is not limited to this and can vary depending on the various factors mentioned above.

[0049] Figure 3 and Figure 4 This is a view illustrating the operation of an X-ray inspection apparatus according to an embodiment of the present disclosure.

[0050] first, Figure 3The diagram illustrates the application of a first voltage to the gate 120 with both the cathode and anode voltages provided as fixed values. For example, when the anode voltage is determined to be in the range of approximately +40 kV to +150 kV and the cathode voltage is determined to be in the range of 0 kV to -1.2 kV, the gate voltage can be a floating value of approximately 0 kV to -0.6 kV with reference to the cathode voltage being determined.

[0051] Specifically, when the cathode voltage is -500 V and the anode voltage is 100 kV, the first voltage of the gate voltage can be set to approximately -800 V.

[0052] When the gate voltage is sufficiently greater than the cathode voltage in the negative direction, the electric field formed by the gate 120 can act as a repulsive force on the electron beam. Accordingly, as... Figure 3 As shown, it can block the electron beam from passing through the gate 120.

[0053] Figure 4 The diagram illustrates the state in which a second voltage is applied to the gate 120. As in the example above, when the cathode voltage is -500 V and the anode voltage is 100 kV, the second voltage of the gate voltage can be set to approximately -530 V.

[0054] The voltage range of the gate voltage can be set differently depending on factors such as the distance between the cathode 110 and the anode 130, the distance between the cathode 110 and the gate 120, the voltage amplitude, and the area. For example, the cathode 110 and the gate 120 can be about 0.1 mm apart, but the distance is not limited to this and can be modified in various ways according to design specifications.

[0055] When Figure 3 When the first voltage is applied as shown, the electron beam can be blocked, thereby preventing the generation of X-rays, and when... Figure 4 When the second voltage is applied, the electron beam can be focused and projected toward the anode 130. Therefore, the on / off control of X-ray generation can be easily performed without the need for the X-ray inspection device's own on / off control. In conventional equipment, on / off control at the level of several Hz to hundreds of Hz is not possible when the X-ray inspection device is turned on. Therefore, the lifespan of the target may be shortened, requiring frequent replacement of the X-ray tube, or the effects of radiation exposure may be significant. Furthermore, if the object to be inspected is moving, long X-ray exposure times may result in residual images in the X-ray image, thus reducing the quality of the X-ray image. However, according to this embodiment, on / off control can be performed quickly. Therefore, even for moving objects, high-quality images can be ensured, the lifespan of the target can be extended by minimizing unnecessary X-ray generation, and radiation exposure can also be minimized.

[0056] Figure 5 This is a view illustrating an example configuration of a power supply unit used in an X-ray inspection apparatus according to an embodiment of the present disclosure.

[0057] refer to Figure 5 The power supply unit 150 may include a first power supply to a fourth power supply 151, 152, 153 and 154.

[0058] A first power supply 151 can be connected to the cathode 110, and a second power supply 152 can be connected to the node between the first power supply 151 and the gate 120. A third power supply 153 can be connected to the anode 130, and a fourth power supply 154 can be connected to the heater 140. The second power supply 152 can provide a variable voltage within a predetermined voltage range. Therefore, the gate voltage can be a voltage with an amplitude obtained by adding the voltages of the first and second power supplies.

[0059] As in the example above, when the cathode voltage is -500 V, the anode voltage is 100 kV, and the gate voltage is controlled within the range of -800 V to -530 V, the second power supply 152 can be configured to provide a power supply with a variable voltage within the range of approximately -300 V to -30 V. Consequently, a voltage within the range of -800 V to -530 V, obtained by summing the voltage values ​​of the first power supply 151 and the second power supply 152, can be applied to the gate 120.

[0060] In the above embodiments, the application of a high voltage to the anode has been described, but this disclosure is not necessarily limited to this, and various changes can be made to the amplitude of the voltage applied to the anode or cathode. For example, a high voltage can be applied to the cathode, or it can be applied to both the anode and the cathode.

[0061] By implementing the gate voltage as a floating voltage relative to the cathode voltage, the range of the voltage scale to be controlled can be reduced. Accordingly, short-interval on / off control becomes easier. Although Figure 5 A second power supply 152 providing a voltage with a variable amplitude is shown, but the present disclosure is not limited thereto, and the voltage supply range can also be varied by using multiple power supplies and at least one switch.

[0062] Meanwhile, X-ray inspection devices can be used in various fields, such as industrial non-destructive testing and medical projection imaging. When using X-ray inspection devices for industrial non-destructive testing, multiple objects to be inspected can be transported simultaneously, and the inspection can be performed during transport to quickly inspect multiple objects. Figure 6 An example of an X-ray inspection apparatus is shown that performs the inspection while the object to be inspected is being transported.

[0063] refer to Figure 6 The X-ray inspection apparatus 100 may further include a conveyor belt 170 for transporting the object 10 to be inspected. The object 10 to be inspected can be transported into the interior through an inlet 102 formed in the housing 101 of the X-ray inspection apparatus 100 while being placed on the conveyor belt 170. Although Figure 6 The illustration shows a single object 10 to be inspected placed on the conveyor belt 170, but multiple objects 10 to be inspected can also be placed sequentially on the conveyor belt 170 and fed into the X-ray inspection device 100 in sequence.

[0064] The control unit 160 can wait while a predetermined voltage is applied to the heater 140, cathode 110, and anode 130, respectively, and a first voltage is applied to the grid 120. When the object 10 to be inspected is transported to the inspection position, the control unit 160 can control the power supply unit 150 to apply a second voltage to the grid 120. The control unit 160 can control the power supply unit 150 to alternately adjust the grid voltage to the first voltage and the second voltage during the period when the object 10 to be inspected passes through the section of the inspection position. Accordingly, the control unit 160 can capture multiple X-ray images.

[0065] Figure 7 This is a view illustrating the operation of an X-ray examination apparatus. (Refer to...) Figure 7 During inspection segment 1, until the first object to be inspected arrives and passes the inspection position, control unit 160 can control power supply unit 150 to alternately apply a first voltage and a second voltage. Then, control unit 160 can wait while applying the first voltage to the grid 120 to block the generation of X-rays until the next object to be inspected arrives at the inspection position. Then, when the next object to be inspected arrives at the inspection position, control unit 160 can control power supply unit 150 to again alternately adjust the voltage amplitude during inspection segment 2.

[0066] The above description illustrates the case of alternately providing the first voltage and the second voltage. However, if necessary, the X-ray inspection apparatus can also adjust the amount of electron beam by applying a voltage with an amplitude within the range between the first voltage and the second voltage to the grid.

[0067] Figure 8 The diagram illustrates a scenario where a first voltage and a second voltage are applied alternately during the first inspection section 1, and a first voltage and a third voltage are applied alternately during the second inspection section 2. The control unit 160 can selectively adjust the amplitude of the gate voltage based on factors such as the size, type, material, and shape of the object to be inspected.

[0068] Meanwhile, during the inspection, image capture can be performed while adjusting the amount of electron beam without completely blocking it. Figure 9 The diagram illustrates the adjustment of the electron beam amount during the inspection section.

[0069] refer to Figure 9 When the inspection section begins, the control unit 160 can control the power supply unit 150 to apply a first voltage to the gate 120 while simultaneously applying a second voltage to the gate 120, and then control the power supply unit 150 to alternately apply the second voltage and a fourth voltage. Then, during the waiting period, the control unit 160 can control the power supply unit 150 to apply the first voltage again.

[0070] Meanwhile, when the object to be examined is a human body, the thickness of the chest may change during inhalation and exhalation. Accordingly, the control unit 160 can perform control to generate different amounts of X-rays during inhalation and exhalation to accurately capture images.

[0071] Specifically, the control unit 160 can control the power supply unit 150 to alternately adjust the gate voltage within a predetermined voltage range based on the respiratory cycle of the human body, which is the object to be inspected. In the example above, the gate voltage can be alternately provided between -800 V and -530 V. However, this disclosure is not necessarily limited to this, and the amplitude range of the gate voltage can be determined as an appropriate amplitude based on the amplitude range of the voltages applied to at least one of the anode and cathode. The inhalation and exhalation cycles can be directly input by the inspector or can be identified based on the sensing values ​​of at least one sensor attached to the object to be inspected.

[0072] Figure 10 This is a flowchart illustrating inspection methods according to various embodiments of the present disclosure. Reference Figure 10 With a predetermined anode voltage and a predetermined cathode voltage applied to the anode and cathode respectively (S1010), a gate voltage within a predetermined voltage range can be selectively applied to the gate located between the cathode and anode (S1020). Therefore, the amount of electron beam emitted from the cathode and transferred toward the anode can be adjusted.

[0073] Adjusting the amount of electron beam by regulating the gate voltage (S1020) can be performed within a voltage range between a first voltage used to block the electron beam and a second voltage used to allow the electron beam to pass. The voltage range of the gate voltage and the structure and operation of components such as the anode, gate, and cathode are specifically described in the various embodiments described above, and therefore redundant descriptions thereof are omitted.

[0074] The above-described inspection method can also be performed by an X-ray inspection apparatus equipped with the configurations described in the various embodiments above. However, this disclosure is not necessarily limited to this, and the inspection method can also be performed by inspection apparatuses with various other configurations.

[0075] As described above, according to various embodiments of this disclosure, control over whether to generate X-rays can be easily and quickly performed without requiring on / off control of the X-ray inspection apparatus itself. Accordingly, X-rays can be generated only during actual image capture, thereby minimizing the amount of radiation exposure to a person or object. Furthermore, the lifespan of the target or X-ray tube can be extended as much as possible. Additionally, inspections of moving items can be performed more precisely. Consequently, inspections of multiple products can be performed quickly and accurately.

[0076] The above description is merely an illustration of the technical concept of this disclosure. Various modifications and variations can be made by those skilled in the art without departing from the essential characteristics of this disclosure. Furthermore, the embodiments according to this disclosure are not intended to limit the technical concept of this disclosure, but rather to describe it, and the scope of the technical concept of this disclosure is not limited by these embodiments. Accordingly, the scope of protection of this disclosure should be interpreted based on the following set forth claims, and all technical concepts within the scope of their equivalents should be interpreted as being included within the scope of the rights of this disclosure.

Claims

1. An X-ray inspection device, comprising: Anode, on which the target is mounted; Cathode, the cathode being used to emit an electron beam toward the target; A gate, wherein the gate is positioned between the cathode and the anode and the gate is closer to the cathode; A power supply unit configured to apply voltages to the cathode, the gate, and the anode, respectively; as well as Control unit The control unit is configured as follows: The power supply unit is controlled to apply a predetermined cathode voltage to the cathode and a predetermined anode voltage to the anode, and By selectively applying a gate voltage within a predetermined voltage range to the gate, the power supply unit is controlled to regulate the amount of the electron beam emitted from the cathode and transferred toward the anode.

2. The apparatus according to claim 1, wherein, The control unit is configured to adjust the amplitude of the gate voltage within a voltage range between a first voltage for blocking the electron beam and a second voltage for allowing the electron beam to pass. The first voltage is a voltage having the same polarity as the cathode voltage, and is set such that the amplitude of the electron beam emitted from the cathode can be blocked by the repulsive force generated by the gate. The second voltage is a voltage having the same polarity as the cathode voltage, and is set to be the amplitude of the electron beam emitted from the cathode being focused by the repulsive force generated by the gate and passing through the gate.

3. The apparatus according to claim 2, further comprising: A conveyor belt, used for transporting objects to be inspected. The control unit is configured to, when the object to be inspected is transported by the conveyor belt to the inspection position, alternately adjust the gate voltage to the first voltage and the second voltage during the period when the object to be inspected passes through the inspection position, while the cathode voltage is applied to the cathode and the anode voltage is applied to the anode.

4. The apparatus according to claim 1, wherein, The control unit is configured to control the power supply unit to alternately adjust the gate voltage within a predetermined voltage range based on the respiratory cycle of the human body, which is the object to be inspected.

5. The apparatus according to claim 1, wherein, The power supply unit includes: A first power source is connected to the cathode; A second power source, the second power source being connected to a node between the first power source and the gate; and A third power source, which is connected to the anode. The second power source is a power source for providing a variable voltage within the predetermined voltage range, and The gate voltage is a voltage having an amplitude obtained by adding the voltage of the first power supply and the voltage of the second power supply.

6. A method for inspection using an X-ray inspection apparatus, the method comprising: A predetermined anode voltage and a predetermined cathode voltage are applied to the anode and cathode, respectively. as well as The amount of electron beam emitted from the cathode and transferred toward the anode is adjusted by selectively applying a gate voltage within a predetermined voltage range to the gate, which is positioned between the cathode and the anode and closer to the cathode.

7. The method according to claim 6, wherein, The adjustment of the electron beam includes adjusting the amplitude of the gate voltage within a voltage range between a first voltage for blocking the electron beam and a second voltage for allowing the electron beam to pass. The first voltage is a voltage having the same polarity as the cathode voltage, and is set such that the amplitude of the electron beam emitted from the cathode can be blocked by the repulsive force generated by the gate. The second voltage is a voltage having the same polarity as the cathode voltage, and is set to be the amplitude of the electron beam emitted from the cathode being focused by the repulsive force generated by the gate and passing through the gate.

8. The method according to claim 7, wherein, The adjustment of the electron beam includes: when the object to be inspected is transported by the conveyor belt to the inspection position while the cathode voltage is applied to the cathode and the anode voltage is applied to the anode, the gate voltage is alternately adjusted to the first voltage and the second voltage during the period when the object to be inspected passes through the section of the inspection position, while the object to be inspected is transported by the conveyor belt to the inspection position.

9. The method according to claim 6, wherein, The adjustment of the amount of electron beam includes: alternating the gate voltage within the predetermined voltage range based on the respiratory cycle of the human body, which is the object to be examined.

Images