X-ray examination apparatus

Abstract

An X-ray inspection apparatus includes a support portion that supports an object having a layered structure, an X-ray generation portion that irradiates the object with X-rays, and an X-ray detection portion that detects the X-rays that have passed through the object. The X-ray generation portion has an electron source that emits an electron beam and a target that emits X-rays in response to the incidence of the electron beam. When viewed from a direction in which the object and the target face each other, the shape of an electron beam irradiation region on the target is an elongated shape having a direction intersecting the stacking direction of the layered structure as a long side direction.

Description

Technical Field

[0001] This disclosure relates to an X-ray inspection apparatus. Background Technology

[0002] An X-ray inspection apparatus is known, comprising: a support for supporting an object; an X-ray generating unit for irradiating the object with X-rays; an X-ray detection unit for detecting X-rays passing through the object, the X-ray generating unit having an electron source for emitting an electron beam; and a target for emitting X-rays based on the incident electron beam (for example, see Japanese Patent Application Publication No. 2023-107307). Utility Model Content

[0003] In the X-ray inspection apparatus described above, to ensure that the resolution of the acquired X-ray transmitted image does not differ with direction (for example, to ensure that the longitudinal resolution and lateral resolution in the acquired X-ray transmitted image are not different), it is usually controlled such that the shape of the X-ray focal spot, i.e., the shape of the electron beam irradiation area on the target, is circular when viewed from the object side. In such an X-ray inspection apparatus, it is known that if an object with a stacked structure is used as the inspection object, resolution can be obtained, but sometimes the brightness becomes insufficient.

[0004] Therefore, the purpose of this disclosure is to provide an X-ray inspection apparatus that can obtain an X-ray transmission image of the stacked structure with sufficient brightness and resolution when the object having the stacked structure is the object to be inspected.

[0005] One aspect of the X-ray inspection apparatus disclosed herein is [1] "An X-ray inspection apparatus comprising: a support for supporting an object having a stacked structure; an X-ray generating unit for irradiating the object with X-rays; and an X-ray detection unit for detecting the X-rays that have passed through the object, the X-ray generating unit comprising: an electron source for emitting an electron beam; and a target for emitting the X-rays according to the incident electron beam, wherein, when viewed from a direction in which the object and the target are opposite to each other, the shape of the electron beam irradiation area on the target is an elongated shape with the direction intersecting the stacking direction of the stacked structure as the long side direction."

[0006] In the aforementioned X-ray inspection apparatus, when viewed from a direction where the object and the target are opposite each other, the shape of the electron beam irradiation area on the target is an elongated shape with the direction intersecting the stacking direction of the stacked structure as its long side. Therefore, when viewed from the object side, the width of the electron beam irradiation area in the stacking direction of the stacked structure is smaller. Thus, sufficient resolution can be obtained in the X-ray transmitted image in the stacking direction of the stacked structure. Furthermore, if we compare the elongated electron beam irradiation area (with the direction intersecting the stacking direction of the stacked structure as its long side) when viewed from the object side with a circular electron beam irradiation area when viewed from the object side, then when the widths of the elongated and circular electron beam irradiation areas in the stacking direction of the stacked structure are equal, the resolution of the X-ray transmitted image in the stacking direction of the stacked structure is equal. However, the width of the electron beam irradiation area in the direction intersecting the stacking direction of the stacked structure is larger in the elongated electron beam irradiation area compared to the circular electron beam irradiation area. Therefore, compared to a circular electron beam irradiation area, a long strip-shaped electron beam irradiation area irradiates the object with a larger amount of X-rays, resulting in sufficient brightness in the X-ray transmitted image. Thus, according to the above-described X-ray inspection apparatus, when an object with a layered structure is examined, an X-ray transmitted image of the layered structure can be obtained with sufficient brightness and resolution.

[0007] One aspect of the X-ray inspection apparatus disclosed herein may also be [2] "the X-ray inspection apparatus according to [1] above, wherein the maximum width of the electron beam irradiation area in the direction of the long side is more than twice the maximum width of the electron beam irradiation area in the direction perpendicular to the direction of the long side." According to this X-ray inspection apparatus, it is possible to obtain X-ray transmission images of stacked structures with sufficient brightness and resolution more reliably.

[0008] One aspect of the X-ray inspection apparatus disclosed herein may also be [3] "the X-ray inspection apparatus according to [1] or [2] above, wherein the target has a surface on which the electron beam irradiation area is formed, and the first angle formed between the first optical axis of the electron source through the electron beam irradiation area and the surface and the second angle formed between the second optical axis of the X-ray detection unit through the electron beam irradiation area and the surface are different from each other." According to this X-ray inspection apparatus, a structure in which the shape of the electron beam irradiation area is elongated when viewed from the object side can be realized with a simple structure.

[0009] One aspect of the X-ray inspection apparatus disclosed herein may also be [4] "the X-ray inspection apparatus according to any one of [1] to [3] above, wherein the X-ray generating unit further comprises: an electron lens that shapes the electron beam in such a way that the cross-sectional shape of the electron beam perpendicular to the first optical axis of the electron source passing through the electron beam irradiation area is elongated." According to this X-ray inspection apparatus, it is possible to reliably achieve a structure in which the shape of the electron beam irradiation area is elongated when viewed from the object side.

[0010] One aspect of the X-ray inspection apparatus disclosed herein may be [5] "the X-ray inspection apparatus according to any one of [1] to [4] above, wherein the object is a lithium-ion battery, and the lithium-ion battery, in a state supported by the support portion, has, as the stacked structure, a structure in which the positive and negative electrodes are alternately arranged via a separator in a cross section perpendicular to the second optical axis of the X-ray detection portion passing through the electron beam irradiation area." According to this X-ray inspection apparatus, in the obtained X-ray transmitted image of the lithium-ion battery, the stacked state of the positive and negative electrodes via the separator can be confirmed with sufficient brightness and resolution. Attached Figure Description

[0011] Figure 1 This is a structural diagram of an example X-ray inspection device.

[0012] Figure 2 yes Figure 1 The diagram shows a partial cross-sectional view of the X-ray generating section.

[0013] Figure 3 It indicates that it was formed in Figure 2 The diagram shows the electron beam irradiation area on the target.

[0014] Figure 4 This is a diagram showing the relationship between the shape of the electron beam irradiation area and the resolution of the stacked pattern when viewed from the object side in a comparative example.

[0015] Figure 5 This is a diagram illustrating the relationship between the shape of the electron beam irradiation area and the resolution of the stacked pattern when viewed from the object side in the embodiment.

[0016] Figure 6 This is a diagram showing the electron beam irradiation area in the modified example.

[0017] Figure 7 This is a diagram showing the electron beam irradiation area in the modified example.

[0018] Figure 8 This is a diagram showing the electron beam irradiation area in the modified example.

[0019] Figure 9 It is a diagram representing the object in the variation example. Detailed Implementation

[0020] Hereinafter, an example of this disclosure will be described in detail with reference to the accompanying drawings. Furthermore, in the various drawings, the same or equivalent parts are given the same reference numerals, and repeated descriptions are omitted.

[0021] like Figure 1 As shown, the X-ray inspection apparatus 1 includes a support 2, an X-ray generating unit 3, and an X-ray detection unit 4. The X-ray inspection apparatus 1 is a device for acquiring an X-ray transmitted image of an object S having a stacked structure S1, using the object S as the object of inspection. For example, it acquires a CT (Computed Tomography) image of the object S. In this example, the object S is a lithium-ion battery 100A of a type called a square. In the lithium-ion battery 100A, a positive electrode 102 and a negative electrode 103 are stacked in one direction within a cuboid-shaped package 101 via a separator 104, thereby forming a stacked structure S1. In this case, this one direction is the stacking direction D1 of the stacked structure S1. Hereinafter, the three mutually perpendicular directions will be referred to as the X-axis direction, the Y-axis direction, and the Z-axis direction. In this example, the Z-axis direction is the vertical direction, and the X-axis and Y-axis directions are horizontal directions.

[0022] The support portion 2 supports the lithium-ion battery 100A with the stacking direction D1 aligned with the X-axis direction. The support portion 2 is capable of rotating (self-rotation) with an axis perpendicular to the Z-axis as its centerline. When a CT image of the lithium-ion battery 100A is acquired, the lithium-ion battery 100A is rotated by rotating the support portion 2. As an example, the support portion 2 may be a support platform for placing the lithium-ion battery 100A, a holding mechanism for holding the lithium-ion battery 100A, etc.

[0023] The X-ray generating unit 3 irradiates the lithium-ion battery 100A, supported by the support unit 2, with X-rays from one side in the Y-axis direction. For example... Figure 2 As shown, the X-ray generating unit 3 includes an X-ray tube 7, a power supply unit 8, and a cylindrical component 9. The cylindrical component 9 has a first opening 9a and a second opening 9b. The first opening 9a and the second opening 9b are opposite each other on the tube axis TA. The X-ray tube 7 is mounted at the end of the cylindrical component 9 on the side of the first opening 9a. The power supply unit 8 is mounted at the end of the cylindrical component 9 on the side of the second opening 9b. In this example, the tube axis TA is parallel to the Y-axis direction. Furthermore, in... Figure 2 In the middle, the front end of the cylindrical component 9 and the socket 84 described below are shown in cross section.

[0024] The power supply unit 8 is constructed by embedding a high-voltage generating unit 82, a high-voltage line 83, and the base end of a socket 84 within an insulating block 81. The insulating block 81 is formed, for example, of an insulating resin such as epoxy resin. A conductive coating is applied to the outer surface of the insulating block 81 to make its potential grounded. The base end of the socket 84 is electrically connected to the high-voltage generating unit 82 via the high-voltage line 83. The front end of the socket 84 is disposed inside the cylindrical component 9 via a second opening 9b, located on the tube shaft TA.

[0025] In the X-ray tube 7, a vacuum housing is formed by a tube 71, a head 72, and a side tube 73. The tube 71 is disposed inside the cylindrical member 9 via a first opening 9a, and the head 72 is disposed on the outer side of the cylindrical member 9 opposite to the tube 71 and the power supply unit 8. In this state, a flange 72a provided on the head 72 is mounted to the end of the cylindrical member 9 on the side of the first opening 9a. The side tube 73 is connected to the side wall of the head 72 in such a way that its centerline intersects (e.g., orthogonally) the tube axis TA. A window member 74 is provided on the top wall of the head 72. The window member 74 is located on the tube axis TA. As an example, the tube 71 is formed of an insulating material such as glass, and the head 72 and the side tube 73 are formed of a conductive material such as metal.

[0026] In the X-ray tube 7, an anode component 75 extends along the tube axis TA inside the tube 71 and the head 72. The anode component 75 has a front end face 75a on the side of the window component 74 and a base end face 75b on the opposite side of the window component 74. The anode component 75 hermetically penetrates the bottom wall of the tube 71. The base end face 75b of the anode component 75 is electrically and physically connected to the front end of the socket 84 of the power supply section 8 on the outside of the tube 71. A target 76 is provided at the front end face 75a of the anode component 75. The target 76 is formed into a film, for example, from tungsten. The front end face 75a of the anode component 75 is inclined relative to the electron gun (electron source) 77 and the window component 74. The electron gun 77 is housed within a side tube 73. The electron gun 77 emits an electron beam. The target 76 emits X-rays based on the incident electron beam.

[0027] In the X-ray generating unit 3, the socket 84 constitutes the power supply unit 11. The power supply unit 11 is disposed inside the cylindrical member 9 and is electrically connected to a portion of the X-ray tube 7 (in this example, the base end 75b of the anode member 75). In the X-ray generating unit 3, the cylindrical member 9 and the power supply unit 8 constitute the receiving unit 12. That is, the receiving unit 12 includes the cylindrical member 9 and the power supply unit 8. The receiving unit 12 receives a portion of the X-ray tube 7 (in this example, the tube 71 and the base end 75b of the anode member 75) and the socket 84 in such a manner that they are located within the insulating oil 10.

[0028] In the X-ray generating unit 3 configured as described above, as an example, the head 72 and side tube 73 are set to ground potential, and a positive voltage is applied to the anode component 75 and the target 76 through the power supply unit 8. In this state, if the electron beam emitted from the electron gun 77 is focused on the target 76, X-rays are emitted from the electron beam irradiation area on the target 76, with the electron beam irradiation area as the focal point, and the X-rays are emitted to the outside through the window component 74. In this way, the X-ray tube 7 is configured as a reflective X-ray tube.

[0029] like Figure 1 As shown, the X-ray detection unit 4 is opposite to the X-ray generating unit 3 in the Y-axis direction. The X-ray detection unit 4 detects X-rays emitted from the X-ray generating unit 3 and passing through the lithium-ion battery 100A. As an example, the X-ray detection unit 4 is an indirect conversion type X-ray detector, having a scintillator and a light-receiving element array. The scintillator emits light according to the incident X-rays. The light-receiving element array is arranged on the opposite side of the X-ray generating unit 3 relative to the scintillator, detecting the light emitted in the scintillator. Alternatively, the X-ray detection unit 4 can also be a direct conversion type X-ray detector.

[0030] like Figure 1 , Figure 2 as well as Figure 3 As shown, the shape of the electron beam irradiation region R on the target 76 of the X-ray generating unit 3, when viewed from the Y-axis direction where the lithium-ion battery 100A and the target 76 are opposite each other, is an elongated shape with the direction intersecting the stacking direction D1 of the stacked structure S1 set as the long side direction D2. In other words, the support unit 2 supports the lithium-ion battery 100A in such a way that the shape of the electron beam irradiation region R when viewed from the object S side is an elongated shape with the direction intersecting the stacking direction D1 of the stacked structure S1 set as the long side direction D2. Figure 3 As shown in (a), in this example, the maximum width W1 of the electron beam irradiation region R along the long side direction D2 is more than twice the maximum width W2 of the electron beam irradiation region R in the direction perpendicular to the long side direction D2. As an example, W1 is 20 μm to 40 μm, and W2 is 10 μm to 20 μm. Figure 3 (a) shows the shape of the electron beam irradiation area R as viewed from the object S side.

[0031] Here, a long strip shape refers to a shape whose maximum width in one direction is greater than its maximum width in a direction perpendicular to that direction (e.g., an ellipse, a long circle, a rectangle, etc.), and the direction of the long side refers to that direction. In this example, the electron beam E traveling toward the target 76 is focused into a cone shape with the first optical axis A1 of the electron gun 77 as the center line. In this example, the shape of the electron beam irradiation area R when viewed from the object S side is elliptical, and its long side direction D2 is consistent with the Z-axis direction.

[0032] like Figure 3 As shown in (b), the first angle θ1 formed by the first optical axis A1 of the electron gun 77 through the electron beam irradiation region R and the surface 76a of the target 76, and the second angle θ2 formed by the second optical axis A2 of the X-ray detection unit 4 through the electron beam irradiation region R and the surface 76a of the target 76, are different. Surface 76a is the surface of the target 76 in which the electron beam irradiation region R is formed. In this example, the surface 76a of the target 76 and the front end face 75a of the anode component 75 are inclined such that the second angle θ2 is smaller than the first angle θ1. In this example, the second optical axis A2 of the X-ray detection unit 4 is aligned with the tube axis TA of the X-ray tube 7. It should be noted that, as Figure 1 As shown, the lithium-ion battery 100A, when supported by the support part 2, has a stacked structure S1, which can be said to have a structure in which the positive electrode 102 and the negative electrode 103 are alternately arranged via the separator 104 in a cross section perpendicular to the second optical axis A2 of the X-ray detection part 4.

[0033] As explained above, in the X-ray inspection apparatus 1, the shape of the electron beam irradiation area R when viewed from the object S side is an elongated shape with the direction intersecting the stacking direction D1 of the stacked structure S1 set as the long side direction D2. Therefore, when viewed from the object S side, the width of the electron beam irradiation area R in the stacking direction D1 of the stacked structure S1 becomes smaller. Consequently, sufficient resolution can be obtained in the X-ray transmitted image along the stacking direction D1 of the stacked structure S1. Furthermore, if we compare an elongated electron beam irradiation region R, which is elongated in the direction intersecting the stacking direction D1 of the stacked structure S1 with its long side direction D2 when viewed from the object S side, with a circular electron beam irradiation region R when viewed from the object S side, then in both the elongated and circular electron beam irradiation regions R, if the widths of the electron beam irradiation regions R along the stacking direction D1 of the stacked structure S1 are equal (for example, if the diameter of the circular electron beam irradiation region R is W2), then the resolution of the X-ray transmitted image along the stacking direction D1 of the stacked structure S1 is equal. However, the width of the electron beam irradiation region R along the direction intersecting the stacking direction D1 of the stacked structure S1 is larger in the elongated electron beam irradiation region R compared to the circular electron beam irradiation region R (the width is W2 in the circular electron beam irradiation region R and W1 in the elongated electron beam irradiation region R). Therefore, compared to a circular electron beam irradiation region R, a long strip-shaped electron beam irradiation region R irradiates the object S with a larger amount of X-rays, resulting in sufficient brightness in the X-ray transmitted image. Thus, according to the X-ray inspection apparatus 1, when the object S having a stacked structure S1 is the object of inspection, an X-ray transmitted image of the stacked structure S1 with sufficient brightness and resolution can be obtained. Furthermore, when sufficient brightness is achieved, similar to the case where the electron beam irradiation region R is circular when viewed from the object S side, the energy density of the electron beam E in the electron beam irradiation region R can be suppressed. In this case, the lifetime of the target 76 can be extended.

[0034] Figure 4 This is a graph illustrating the relationship between the shape of the electron beam irradiation region R and the resolution of the stacked pattern when viewed from the object side S in a comparative example. For example... Figure 4 As shown in (a) and (b), when the shape of the electron beam irradiation area R is circular when viewed from the object S side, sufficient resolution can be obtained in either of the two stacked patterns with stacking directions D1 perpendicular to each other. However, in this case, if a high-intensity electron beam E is focused on a small area on the target 76 to obtain sufficient brightness, the target lifetime may be shortened. Furthermore, the stacked pattern is a black and white striped pattern with a width of 10 μm, and the diameter of the electron beam irradiation area R is 20 μm.

[0035] Figure 5 This is a diagram illustrating the relationship between the shape of the electron beam irradiation region R and the resolution of the stacked pattern when viewed from the object S side in the embodiment. For example... Figure 5 As shown in (a), when viewed from the object S side, the shape of the electron beam irradiation region R is elliptical. When the long side direction D2 of the electron beam irradiation region R coincides with the stacking direction D1 of the stacked pattern, sufficient resolution cannot be obtained. On the other hand, as... Figure 5 As shown in (b), when viewed from the object S side, the shape of the electron beam irradiation region R is elliptical. Sufficient resolution can be obtained when the long side direction D2 of the electron beam irradiation region R is orthogonal to the stacking direction D1 of the stacked pattern. Furthermore, the stacked pattern is a black and white striped pattern with a width of 10 μm, and the lengths of the major and minor axes of the electron beam irradiation region R are 40 μm and 20 μm, respectively.

[0036] In the X-ray inspection apparatus 1, the maximum width W1 of the electron beam irradiation area R along the long side direction D2 is more than twice the maximum width W2 of the electron beam irradiation area R perpendicular to the long side direction D2. Therefore, it is possible to obtain an X-ray transmitted image of the stacked structure S1 with sufficient brightness and resolution more reliably.

[0037] In the X-ray inspection apparatus 1, the first angle θ1 formed by the first optical axis A1 of the electron gun 77 and the surface 76a of the target 76, and the second angle θ2 formed by the second optical axis A2 of the X-ray detection unit 4 and the surface 76a of the target 76, are different from each other. Therefore, a structure in which the shape of the electron beam irradiation area R is elongated when viewed from the object S side can be achieved with a simple structure.

[0038] In the X-ray inspection apparatus 1, the lithium-ion battery 100A, which is the object S, is supported by the support portion 2 and has a stacked structure S1, in which the positive electrode 102 and the negative electrode 103 are alternately arranged via the separator 104 in a cross section perpendicular to the second optical axis A2 of the X-ray detection portion 4. As a result, in the obtained X-ray transmitted image of the lithium-ion battery 100A, the stacked state of the positive electrode 102 and the negative electrode 103 via the separator 104 can be confirmed with sufficient brightness and resolution.

[0039] This disclosure is not limited to the example mentioned above. For example, such as Figure 6 As shown in (b), the surface 76a of the target 76 can also be tilted with the second angle θ2 greater than the first angle θ1. In this case, when the electron beam E traveling toward the target 76 is focused into a cone shape with the first optical axis A1 of the electron gun 77 as the center line, as... Figure 6As shown in (a), when viewed from the object S side, the shape of the electron beam irradiation region R becomes elliptical, with its long side direction D2 aligned with the X-axis direction. Figure 6 In the example shown, the support portion 2 supports the lithium-ion battery 100A in such a way that the stacking direction D1 of the laminated structure S1 intersects with the long side direction D2 (for example, in such a way that the stacking direction D1 of the laminated structure S1 is aligned with the Z-axis direction). Figure 6 In the example shown, it is also related to Figure 3 Similarly, in the example shown, the second optical axis A2 of the X-ray detection unit 4 is aligned with the tube axis TA of the X-ray tube 7.

[0040] In addition, such as Figure 7 As shown in (b), the second optical axis A2 of the X-ray detection unit 4 may also not be consistent with the tube axis TA of the X-ray tube 7. Figure 7 In the example shown, on the plane containing the first optical axis A1 of the electron gun 77 and the second optical axis A2 of the X-ray detection unit 4, the tube axis TA is tilted relative to the second optical axis A2 to the side opposite to the first optical axis A1. That is, in Figure 7 In the example shown, the X-ray tube 7 is configured such that its tube axis TA is tilted relative to the second optical axis A2 towards the side opposite to the first optical axis A1. In this case, when the electron beam E traveling toward the target 76 is focused into a cone shape with the first optical axis A1 of the electron gun 77 as the center line, as shown... Figure 7 As shown in (a), when viewed from the object S side, the shape of the electron beam irradiation region R becomes elliptical, with its long side direction D2 aligned with the X-axis direction. Figure 7 In the example shown, the support portion 2 supports the lithium-ion battery 100A in such a way that the stacking direction D1 of the laminated structure S1 intersects with the long side direction D2 (for example, in such a way that the stacking direction D1 of the laminated structure S1 is aligned with the Z-axis direction). Figure 7 In the example shown, it is also related to Figure 3 and Figure 6 Similarly, in each of the examples shown, the first angle θ1 and the second angle θ2 are different from each other.

[0041] In addition, such as Figure 8 As shown in (b), an electron lens 78 can also be disposed between the electron gun 77 and the target 76. The electron lens 78 forms the electron beam E in a strip-shaped cross-section, perpendicular to the first optical axis A1 of the electron gun 77. This reliably achieves a structure where the shape of the electron beam irradiation area R is strip-shaped when viewed from the object S side. For example, even if the first angle θ1 and the second angle θ2 are equal, such as Figure 8As shown in (a), the shape of the electron beam irradiation region R when viewed from the object S side is also an elongated shape with the direction intersecting the stacking direction D1 of the stacked structure S1 set as the long side direction D2. The electron lens 78 is, for example, an electric field lens based on electrodes, a magnetic field lens based on coils, etc.

[0042] In addition, such as Figure 9 As shown, the object S can also be a lithium-ion battery 100B of a cylindrical type. In the lithium-ion battery 100B, within a cylindrical package 101, a positive electrode 102 and a negative electrode 103 are wound via a separator 104, thereby forming a laminated structure S1. In this case, the lamination direction D1 of the laminated structure S1 is any radial direction (i.e., any direction perpendicular to the center line CL) relative to the center line CL of the positive electrode 102 and the negative electrode 103 wound via the separator 104. Figure 1 In the example shown, the support portion 2 supports the lithium-ion battery 100B in such a way that the center line CL is parallel to the Z-axis direction. In this case, it can also be said that the lithium-ion battery 100B, supported by the support portion 2, has a structure as a stacked structure S1, in which the positive electrode 102 and the negative electrode 103 are alternately arranged via the separator 104 in a cross section perpendicular to the second optical axis A2 of the X-ray detection portion 4.

[0043] Furthermore, the X-ray tube 7 is not limited to being a reflective X-ray tube; it can also be a transmittant X-ray tube. As an example, in a transmittant X-ray tube 7, an electron gun 77 is disposed inside the tube 71, and a target 76 is provided on the inner surface of the window member 74. In this case, the target 76 is set to ground potential, and a negative voltage is applied to the electron gun 77 via the power supply unit 8. In this state, if the electron beam emitted from the electron gun 77 is focused onto the target 76, X-rays are emitted from the electron beam irradiation area on the target 76, and the X-rays are emitted outward through the window member 74 with the electron beam irradiation area as the focal point. Alternatively, the X-ray generating unit 3 may not have a power supply unit 8. In this case, a high voltage can be supplied to the X-ray tube 7 from the outside via a high-voltage cable.

[0044] According to this disclosure, an X-ray inspection apparatus is provided that can obtain an X-ray transmitted image of the stacked structure with sufficient brightness and resolution when an object having a stacked structure is set as the inspection object.

Claims

1. An X-ray inspection device, wherein, have: A support portion that supports an object having a layered structure; An X-ray generating unit that irradiates the object with X-rays; and The X-ray detection unit detects the X-rays that have passed through the object. The X-ray generating unit has: The electron source from which the electron beam is emitted; as well as A target that emits X-rays based on the incident electron beam. When viewed from the direction in which the object and the target are opposite to each other, the shape of the electron beam irradiation area on the target is a long strip shape with the direction intersecting the stacking direction of the stacked structure as the long side direction.

2. The X-ray inspection apparatus according to claim 1, wherein, The maximum width of the electron beam irradiation area along the long side is more than twice the maximum width of the electron beam irradiation area along the direction perpendicular to the long side.

3. The X-ray inspection apparatus according to claim 1, wherein, The target has a surface on which the electron beam irradiation region is formed. The first angle formed between the first optical axis of the electron source passing through the electron beam irradiation area and the surface, and the second angle formed between the second optical axis of the X-ray detection unit passing through the electron beam irradiation area and the surface, are different from each other.

4. The X-ray inspection apparatus according to claim 1, wherein, The X-ray generating unit also includes an electron lens that shapes the electron beam in such a way that the cross-sectional shape of the electron beam is elongated and perpendicular to the first optical axis of the electron source passing through the electron beam irradiation area.

5. The X-ray inspection apparatus according to any one of claims 1 to 4, wherein, The object in question is a lithium-ion battery. When the lithium-ion battery is supported by the support portion, as the stacked structure, it has a structure in which the positive and negative electrodes are alternately arranged via a separator in a cross section perpendicular to the second optical axis of the X-ray detection portion passing through the electron beam irradiation area.

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