X-ray inspection device and X-ray inspection method

Abstract

An X-ray inspection device (1) is provided with: an X-ray emission device (2) that emits X-rays toward an object to be measured (OB); a scintillator (4) that converts X-rays incident through the measurement object (OB) into visible light; and an imaging device (5) that generates an X-ray image by imaging the visible light from the scintillator (4). The scintillator (4) is disposed such that a boundary BO between an incident surface (41) on which X-rays are incident and a first side surface (42) intersecting the incident surface (41) is located within an X-ray emission range (SP). When the entire region of the first side surface 42 is divided into two regions: a first region Ar1 including a boundary BO and a second region Ar2 other than the first region Ar1, the imaging device 5 is disposed so as to face the first side surface 42, and images visible light emitted from the first region Ar1 in the entire region of the first side surface 42.

Description

Technical Field

[0001] The present invention relates to an X-ray inspection device and an X-ray inspection method. Background Art

[0002] Previously, there is known an X-ray inspection device that radiates X-rays toward a measurement object, converts the X-rays that pass through the measurement object into visible light using a scintillator (using the X-rays to fluoresce and emit visible light), and uses a photographing device to photograph the visible light to generate an X-ray image (for example, refer to Patent Document 1 and Patent Document 2).

[0003] The X-ray inspection device described in Patent Document 1 is a so-called transmission imaging type X-ray inspection device. Specifically, the transmission imaging type X-ray inspection device captures visible light emitted from the surface of the scintillator that is the front and back surfaces of the incident surface for X-rays to enter, thereby generating an X-ray image.

[0004] The X-ray inspection apparatus described in Patent Document 2 is a so-called reflection imaging type X-ray inspection apparatus. Specifically, the reflection imaging type X-ray inspection apparatus captures visible light emitted from an incident surface of a scintillator into which X-rays are incident, and generates an X-ray image.

[0005] Prior art literature

[0006] Patent Literature

[0007] Patent Document 1: Japanese Patent Laid-Open No. 1-262451

[0008] Patent Document 2: Japanese Patent Application Publication No. 2020-160079 Summary of the invention

[0009] Problems to be solved by the invention

[0010] However, in the transmission photography type X-ray inspection device described in Patent Document 1, when X-rays are incident on the scintillator, the visible light converted by the scintillator travels inside the scintillator and is therefore absorbed inside. Therefore, the brightness of the visible light emitted from the surface that is the front and back of the incident surface becomes low, and the X-ray image becomes a dark image. In addition, when a particle-type scintillator is used, the visible light traveling inside the scintillator is easily scattered inside. Therefore, the X-ray image becomes an unclear image.

[0011] That is, in the transmission imaging type X-ray inspection apparatus described in Patent Document 1, there is a problem that the X-ray image becomes a dark image or an unclear image, and it is difficult to obtain an X-ray image suitable for inspection.

[0012] In addition, in the reflection photography type X-ray inspection device described in Patent Document 2, it is necessary to make the visible light emitted from the incident surface of the scintillator for X-rays to enter travel toward the photography device, so it is necessary to tilt the scintillator relative to the measurement object. Therefore, the distance between the measurement object and the scintillator becomes relatively large. As a result, the blur (penumbra) generated in the X-ray image becomes larger, and the X-ray image becomes an unclear image.

[0013] That is, in the reflection imaging type X-ray inspection apparatus described in Patent Document 2, there is a problem that the X-ray image becomes an unclear image, and it is difficult to obtain an X-ray image suitable for inspection.

[0014] Therefore, a technology capable of obtaining an X-ray image suitable for inspection is required.

[0015] The present invention has been made in view of the above, and an object of the present invention is to provide an X-ray inspection apparatus and an X-ray inspection method capable of obtaining an X-ray image suitable for inspection.

[0016] Technical means of solving problems

[0017] In order to solve the above-mentioned problem and achieve the purpose, the X-ray inspection device of the present invention includes: an X-ray radiating device, which radiates X-rays toward a measurement object; a scintillator, which converts the X-rays incident through the measurement object into visible light; and a photographing device, which photographs the visible light from the scintillator to generate an X-ray image, wherein the scintillator is configured in such a way that a boundary between an incident surface for the X-rays to be incident and a first side surface intersecting the incident surface is located within the radiation range of the X-rays, and the photographing device is configured in such a way as to face the first side surface when the entire area of ​​the first side surface is divided into two areas, a first area including the boundary and a second area excluding the first area, and photographs the visible light emitted from the first area in the entire area of ​​the first side surface.

[0018] In addition, in the invention of the X-ray inspection device of the present invention, it also includes: an X-ray shielding component, which is arranged between the measurement object and the scintillator when the entire area of ​​the incident surface is divided into two areas, namely, a third area including the boundary and a fourth area excluding the third area, and shields the X-rays incident on the fourth area in the entire area of ​​the incident surface.

[0019] In the above invention of the X-ray inspection apparatus of the present invention, in the scintillator, a dimension between a second side surface forming a front surface and a back surface with the first side surface and the first side surface is set to be 30 μm or more and 500 μm or less.

[0020] In addition, in the invention of the X-ray inspection device of the present invention, it also includes: an image analysis device for analyzing the X-ray image, and the image analysis device is: based on the brightness distribution of the visible light along the incident direction of the X-ray in the X-ray image, inferring the characteristic value of the abnormal part existing in the measurement object.

[0021] In addition, in the invention of the X-ray inspection device of the present invention, the X-ray radiation device and the scintillator are arranged in such a manner that the width of the penumbra represented by (L2-L1)×R / L1 becomes less than 30 μm when the distance from the X-ray focus of the X-ray radiation device to the measurement object is set to L1 [mm], the distance from the X-ray focus to the scintillator is set to L2 [mm], and the diameter of the X-ray focus is set to R [μm].

[0022] In addition, in the invention of the X-ray inspection device of the present invention, it also includes: a transport device, which enables the measurement object to move relative to the X-ray radiation device, the scintillator, and the imaging device in a direction approximately perpendicular to the first side, or repeatedly performs the relative movement and stopping.

[0023] In addition, the X-ray inspection method of the present invention includes: a scintillator configuration process, in which the scintillator is configured in such a manner that a boundary between an incident surface for X-rays to be incident on and a first side surface intersecting the incident surface in the scintillator is located within the radiation range of the X-rays; a photographing device configuration process, in which the photographing device is configured in such a manner as to face the first side surface; an X-ray irradiation process, in which the X-rays are irradiated from the X-ray device toward a measurement object; and a photographing process, in which the photographing device is used to photograph visible light converted from the X-rays incident on the scintillator via the measurement object to generate an X-ray image, wherein in the photographing process, the visible light emitted from the first area in the entire area of ​​the first side surface is photographed by the photographing device when the entire area of ​​the first side surface is divided into two areas, namely, a first area including the boundary and a second area excluding the first area.

[0024] In addition, in the invention of the X-ray inspection method of the present invention, it also includes: an X-ray shielding component configuration process, in which, when the entire area of ​​the incident surface is divided into two areas, namely, a third area including the boundary and a fourth area excluding the third area, in order to shield the X-rays incident on the fourth area, the X-ray shielding component configuration process configures an X-ray shielding component for shielding the X-rays between the measured object and the scintillator.

[0025] In addition, the invention of the X-ray inspection method of the present invention also includes: an image analysis process for analyzing the X-ray image, in which the characteristic quantity of the abnormal part existing in the measurement object is estimated based on the brightness distribution of the visible light along the incident direction of the X-ray in the X-ray image.

[0026] In addition, in the invention of the X-ray inspection method of the present invention, it also includes: a positional relationship adjustment process for adjusting the positional relationship between the X-ray radiation device and the scintillator, in which the positional relationship between the X-ray radiation device and the scintillator is adjusted in such a way that the width of the penumbra represented by (L2-L1)×R / L1 becomes less than 1 / 6 of the diameter of the defect to be detected relative to the measuring object when the distance from the X-ray focus of the X-ray radiation device to the measuring object is set to L1 [mm], the distance from the X-ray focus to the scintillator is set to L2 [mm], and the diameter of the X-ray focus is set to R [μm].

[0027] In addition, in the invention of the X-ray inspection method of the present invention, it also includes: a transport process, wherein the transport process causes the measurement object to move relative to the X-ray radiation device, the scintillator, and the imaging device in a direction approximately perpendicular to the first side, or repeatedly performs the relative movement and stopping.

[0028] Effects of the Invention

[0029] The X-ray inspection apparatus and the X-ray inspection method of the present invention can obtain an X-ray image suitable for inspection. BRIEF DESCRIPTION OF THE DRAWINGS

[0030] [ Figure 1 ] Figure 1 This is a diagram showing an X-ray inspection apparatus according to the first embodiment.

[0031] [ Figure 2 ] Figure 2 is a flow chart showing an X-ray inspection method.

[0032] [ Figure 3 ] Figure 3 This is a diagram for explaining step S1.

[0033] [ Figure 4 ] Figure 4 This is a diagram for explaining step S5.

[0034] [ Figure 5 ] Figure 5 This is a diagram showing an X-ray inspection apparatus according to a second embodiment.

[0035] [ Figure 6 ] Figure 6 This is a diagram for explaining the effects of the second embodiment.

[0036] [ Figure 7 ] Figure 7 This is a diagram showing an X-ray inspection apparatus according to a third embodiment.

[0037] [ Figure 8 ] Figure 8 This is a diagram for explaining the effects of the third embodiment.

[0038] [ Fig. 9 ] Fig. 9 These are diagrams for explaining modified examples of the first to third embodiments. DETAILED DESCRIPTION

[0039] Hereinafter, the form for implementing the present invention (hereinafter referred to as embodiment) will be described with reference to the drawings. In addition, the present invention is not limited to the embodiment described below. Furthermore, in the description of the drawings, the same symbols are marked on the same parts.

[0040] (Implementation Method 1)

[0041] [Structure of X-ray inspection equipment]

[0042] Figure 1 This is a diagram showing an X-ray inspection apparatus 1 according to the first embodiment.

[0043] X-ray inspection apparatus 1 is directed toward a measurement object OB (such as a film or fiber) Figure 1 ) radiates X-rays, converts the X-rays that have passed through the measuring object OB into visible light, and photographs the visible light to generate an X-ray image. The X-ray inspection device 1 analyzes the X-ray image to estimate a defect DE such as a metal foreign body mixed into the measuring object OB (see Figure 3 )’s feature quantity.

[0044] In addition, the measurement object OB is not limited to a film or fiber, and paper, resin, integrated circuit, etc. can also be used.

[0045] like Figure 1 As shown, the X-ray inspection device 1 includes an X-ray irradiation device 2, a transport device 3, a scintillator 4, an imaging device 5, a display device 6, and a control device 7.

[0046] In the following description of the structure of the X-ray inspection device 1, an axis along the vertical direction is referred to as a Z axis, and two axes orthogonal to the Z axis are referred to as an X axis and a Y axis. Figure 1In the diagram, the Z axis is the axis along the up-down direction. In addition, the X axis is the axis along the left-right direction. Furthermore, the Y axis is Figure 1 An axis that is perpendicular to the plane of paper.

[0047] The X-ray irradiation device 2 is controlled by the control device 7 to emit light from the X-ray focus 21 ( Figure 1 ) radiates a conical X-ray beam (cone beam) toward the measurement object OB. Figure 1 In the figure, the radiation range SP of the conical X-ray beam is represented by dots. In the first embodiment, the radiation direction of the X-rays from the X-ray radiation device 2 is the -Z axis direction ( Figure 1 The middle is the downward direction).

[0048] The X-ray radiating device 2 may be a closed type or an open type, and may be a millifocus type or a microfocus type.

[0049] The conveying device 3 has conveying rollers or a belt conveyor, etc., and conveys the measuring object OB while holding the measuring object OB under the control of the control device 7. In the present embodiment 1, the conveying direction of the measuring object OB is the -X axis direction ( Figure 1 The -X axis direction is a substantially vertical direction of the first side surface 42 described later.

[0050] like Figure 1 As shown, the scintillator 4 includes a plate body that is rectangular in plan view, and the plate surface is arranged on the -Z axis side relative to the measurement object OB in a posture that is substantially parallel to the XY plane. In addition, the scintillator 4 converts the incident X-rays that pass through the measurement object OB into visible light (fluorescence is emitted by the X-rays).

[0051] Here, in the scintillator 4, the +Z axis side ( Figure 1 The plate surface (upper side in the figure) is used for the X-rays passing through the measurement object OB to be incident, which corresponds to the incident surface 41 ( Figure 1 ). In addition, in the scintillator 4, the side surface on the -X axis side intersects with the incident surface 41, which corresponds to the first side surface 42 ( Figure 1 ).

[0052] In addition, the scintillator 4 may be of a particle type or a single crystal type.

[0053] The imaging device 5 includes an imaging element such as a charge coupled device (CCD) or a complementary metal oxide semiconductor (CMOS) that receives incident light and converts it into an electrical signal, and is a camera that generates an X-ray image by capturing visible light from the scintillator 4. Then, the imaging device 5 outputs the data of the generated X-ray image to the control device 7.

[0054] In addition, the imaging device 5 may be a line sensor camera, an area sensor camera, or a time-delay integration camera.

[0055] The display device 6 includes a display monitor using liquid crystal or organic electroluminescence (EL), and displays various images such as X-ray images under the control of the control device 7 .

[0056] The control device 7 uniformly controls the overall operation of the X-ray inspection device 1. Figure 1 As shown, the control device 7 includes: a processor 71 , a storage unit 72 , and an input unit 73 .

[0057] The processor 71 is implemented by executing various programs stored in the storage unit 72 using a controller such as a central processing unit (CPU) or a microprocessing unit (MPU) to control the overall operation of the X-ray inspection apparatus 1 .

[0058] In addition, the processor 71 is not limited to a CPU or an MPU, and may include an integrated circuit such as an application specific integrated circuit (ASIC) or a field programmable gate array (FPGA). The function of the processor 71 will be described in the "X-ray inspection method" described later.

[0059] The storage unit 72 stores various programs executed by the processor 71 and also stores data and the like necessary for the processor 71 to perform processing.

[0060] The input unit 73 includes buttons, switches, touch screens, etc. that receive user operations performed by an operator, and outputs operation signals corresponding to the user operations to the processor 71. In addition, part or all of the functions of the input unit 73 may also be configured as a touch screen on the display screen of the display device 6.

[0061] [X-ray inspection method]

[0062] Next, an X-ray inspection method using the X-ray inspection apparatus 1 will be described.

[0063] Figure 2 is a flow chart showing an X-ray inspection method.

[0064] First, the operator performs initial settings of the X-ray inspection apparatus 1 (step S1 ).

[0065] Figure 3 2 is a diagram for explaining step S1. Specifically, Figure 3 2 is a diagram showing the positional relationship among the X-ray irradiation device 2, the measurement object OB, and the scintillator 4. Figure 3 In the figure, the symbol "R" is the diameter of the X-ray focus 21 [μm]. In addition, the symbol "L1" is the distance from the X-ray focus 21 to the measurement object OB [mm]. Furthermore, the symbol "L2" is the distance from the X-ray focus 21 to the scintillator 4 [mm]. In addition, the symbol "r" is the width of the penumbra (blur) SH [μm].

[0066] Here, the penumbra SH in X-ray inspection will be described.

[0067] In X-ray inspection, when the distance (L2-L1) from the measuring object OB to the scintillator 4 is increased and the shadow of defects DE such as metal foreign matter mixed into the measuring object OB caused by the radiated X-rays is geometrically increased, the detection sensitivity of tiny defects DE is reduced.

[0068] Specifically, the X-ray focus 21 has a finite diameter R [μm]. Therefore, the X-ray enters the area that should be the shadow of the defect DE, thereby generating a penumbra SH ( Figure 3 ). That is, a penumbra SH is generated in a portion that originally serves as a shadow of the defect DE, thereby making it difficult to detect the defect DE with high accuracy.

[0069] It is assumed that the penumbra SH is generated at both ends of the defect DE. Therefore, the shadow of the defect DE is smaller than it should be by an amount corresponding to 2×r. Here, the width r of the penumbra SH is represented by (L2-L1)×R / L1.

[0070] The inventors of the present application have conducted intensive studies and found that in order to stably detect the defect DE, the width r of the penumbra SH needs to be 1 / 6 or less of the diameter of the defect DE. In the first embodiment, the diameter of the defect DE is 30 μm or more and 200 μm or less.

[0071] Then, in step S1 , the operator sets the diameter of the defect DE to be detected with respect to the measuring object OB to about 180 μm, and adjusts the distances L1 and L2 , thereby setting the width r of the penumbra SH to be less than 1 / 6 (30 μm) of the above 180 μm.

[0072] In addition, in step S1, the operator uses the boundary BO ( Figure 1 ) is located within the radiation range SP of X-rays, and the scintillator 4 is configured.

[0073] Furthermore, in step S1 , the operator arranges the imaging device 5 so as to face the first side surface 42 .

[0074] As described above, step S1 corresponds to the positional relationship adjustment step, the scintillator arrangement step, and the imaging device arrangement step of the present invention.

[0075] After step S1, the operator operates the input unit 73 to start the X-ray inspection. Thereby, the processor 71 executes the following processing.

[0076] First, the processor 71 operates the transport device 3 to transport the measurement object OB at a predetermined speed (step S2: transport step).

[0077] After step S2, the processor 71 operates the X-ray radiating device 2. Then, the X-ray radiating device 2 radiates X-rays toward the measurement object OB (step S3: X-ray radiating step).

[0078] After step S3, the processor 71 operates the imaging device 5. Then, the imaging device 5 captures the X-rays incident on the scintillator 4 via the measurement object OB and converted into visible light by the scintillator 4, thereby generating an X-ray image (step S4: imaging process). In addition, the imaging device 5 outputs the data of the generated X-ray image to the control device 7.

[0079] Here, it is assumed that the entire area of ​​the first side surface 42 is divided into a first area Ar1 including the boundary BO (see Figure 4 ) and the second area Ar2 (refer to Figure 4 ) In this case, in step S4, the imaging device 5 is used to capture visible light emitted from the first area Ar1 in the entire area of ​​the first side surface 42. That is, in step S4, the imaging device 5 is used to capture visible light emitted from the area (first area Ar1) near the boundary BO in the entire area of ​​the first side surface 42.

[0080] After step S4, the processor 71 acquires the data of the X-ray image generated in step S4 from the imaging device 5, and analyzes the X-ray image (step S5: image analysis step). Thereafter, the processor 71 returns to step S2.

[0081] Figure 4 2 is a diagram for explaining step S5. Specifically, Figure 4 (a) shows an X-ray image F1 when the thickness of the defect DE mixed in the measurement object OB is large or the density of the defect DE is high. Figure 4 (b) shows an X-ray image F2 when the thickness of the defect DE mixed into the measurement object OB is small or the density of the defect DE is low. Figure 4 In the region ArS1 and region ArS2 that are shadows of the defect DE caused by the X-rays, the lower the brightness of the visible light converted from the X-rays, the higher the density of the dots. Figure 4 In the figure, for the sake of convenience, the points are not marked in the first side surface 42 in areas other than the area ArS1 and the area ArS2.

[0082] For example, if a defective DE is mixed in, Figure 4 As shown, the X-rays are absorbed by the defect DE, and regions ArS1 and ArS2 are generated as shadows of the defect DE. In the regions ArS1 and ArS2, in the region close to the incident surface 41, the brightness of the visible light converted from the X-rays becomes low due to the absorption of the X-rays by the defect DE. Moreover, in the regions ArS1 and ArS2, as the direction moves toward the -Z direction, the brightness of the visible light gradually increases due to the influence of the visible light from the regions other than the regions ArS1 and ArS2, and finally becomes substantially the same as the brightness of the visible light from the regions other than the regions ArS1 and ArS2.

[0083] Here, if Figure 4 (a) and Figure 4 As can be seen from the comparison of (b), when the thickness or density of the defect DE is different, the length of the region ArS1 and the region ArS2 in the Z-axis direction and the brightness distribution of the visible light along the Z-axis direction are different. Specifically, the length of the region ArS1 in the Z-axis direction is longer than the length of the region ArS2 in the Z-axis direction. That is, there is a correlation between the characteristic quantity such as the thickness or density of the defect DE and the brightness distribution of the visible light along the Z-axis direction (the incident direction of the X-ray) in the X-ray image. In addition, the storage unit 72 stores relevant information indicating the correlation.

[0084] In addition, the brightness distribution of the visible light along the Z-axis direction also depends on the length of the defect DE in the Y-axis direction. Therefore, the feature quantity constituting the relevant information stored in the storage unit 72 may include the length of the defect DE in the Y-axis direction in addition to the thickness or density of the defect DE.

[0085] In step S5, the processor 71 obtains the brightness distribution (light receiving amount distribution) of visible light along the Z-axis direction based on the X-ray image generated in step S4, and estimates the feature quantity corresponding to the brightness distribution by referring to the relevant information stored in the storage unit 72. That is, the control device 7 is equivalent to the image analysis device of the present invention.

[0086] Here, in order to obtain the light receiving amount distribution in step S5, the Z-axis direction ( Figure 4 The length dimension in the Y-axis direction (in the vertical direction) of the scintillator 4 is preferably 200 μm or more. Figure 4 The length dimension (in the left-right direction) is about 60 mm to 100 mm.

[0087] According to the first embodiment described above, the following effects are achieved.

[0088] In the X-ray inspection apparatus 1 of the first embodiment, the scintillator 4 is arranged so that the boundary BO is located within the radiation range SP of the X-rays. In addition, the imaging device 5 is arranged so as to face the first side surface 42, and images visible light emitted from the first area Ar1 including the boundary BO in the entire area of ​​the first side surface 42.

[0089] That is, the imaging device 5 does not capture visible light transmitted through the scintillator as in the transmission imaging type X-ray inspection device described in Patent Document 1, but captures visible light emitted from the first area Ar1 in the first side surface 42. In other words, the imaging device 5 captures visible light that is less affected by absorption or scattering inside the scintillator 4. Therefore, a bright and clear X-ray image can be generated.

[0090] In addition, since there is no need to tilt the scintillator relative to the measurement object as in the reflection photography type X-ray inspection apparatus described in Patent Document 2, the scintillator 4 can be brought close to the measurement object OB. Therefore, the width r of the penumbra SH generated in the X-ray image can be reduced, and a clear X-ray image can be generated.

[0091] As described above, the X-ray inspection apparatus 1 according to the first embodiment can obtain an X-ray image suitable for inspection.

[0092] In the reflection photography type X-ray inspection device described in Patent Document 2, the photography device needs to photograph the incident surface of the scintillator. Therefore, the measurement object enters the photography field of the photography device, and the incident surface of the scintillator is easily blocked by the measurement object, making it difficult to set the installation position of the photography device.

[0093] In contrast, in the X-ray inspection apparatus 1 of the first embodiment, the imaging device 5 is disposed so as to face the first side surface 42, and the visible light emitted from the first area Ar1 in the first side surface 42 is captured. Therefore, the first area Ar1 is not blocked by the object to be measured, and the imaging device 5 can be easily installed. In addition, by installing the imaging device 5 so as to face the first side surface 42, the imaging device 5 is not irradiated by X-rays. Therefore, the life of the imaging device 5 can be extended.

[0094] In the X-ray inspection apparatus 1 of the first embodiment, the X-ray radiating device 2 and the scintillator 4 are arranged so that the width r of the penumbra SH becomes 1 / 6 (30 μm) or less of the diameter of the defect DE to be detected with respect to the measuring object OB, that is, 180 μm.

[0095] Therefore, the defect DE can be stably detected.

[0096] In addition, in the X-ray inspection device 1 of the present embodiment 1, the processor 71 estimates the characteristic quantity of the defect DE existing in the measuring object OB based on the brightness distribution (light receiving amount distribution) of visible light along the incident direction of the X-rays in the X-ray images F1 and F2.

[0097] Therefore, the characteristic amount (thickness or density) of the defect DE can be easily estimated through a simple process.

[0098] (Implementation Method 2)

[0099] Next, the second embodiment will be described.

[0100] In the following description, the same reference numerals are used for the same structures as those in the first embodiment, and the detailed description thereof will be omitted or simplified.

[0101] Figure 5 is with Figure 1 , and is a diagram showing an X-ray inspection apparatus 1A according to Embodiment 2. Figure 5 In the figure, for the convenience of explanation, the illustration of the conveying device 3, the imaging device 5, the display device 6, and the control device 7 is omitted.

[0102] In the X-ray inspection apparatus 1A of the second embodiment, Figure 5As shown, an X-ray shielding member 8 is added to the X-ray inspection apparatus 1 described in the first embodiment.

[0103] The X-ray shielding member 8 is a plate body that includes, for example, aluminum or iron, and shields X-rays. Figure 5 As shown, the X-ray shielding member 8 is disposed between the measurement object OB and the scintillator 4 , and shields X-rays incident on a partial region of the entire region of the incident surface 41 .

[0104] In the X-ray inspection method of the second embodiment, in contrast to the X-ray inspection method described in the first embodiment, the X-ray shielding member 8 is disposed in step S1.

[0105] Here, it is assumed that the entire area of ​​the incident surface 41 is divided into a third area Ar3 ( Figure 5 ) and the fourth area Ar4 (excluding the third area Ar3 Figure 5 In this case, the operator arranges the X-ray shielding member 8 between the measurement object OB and the scintillator 4 in step S1 to shield the X-rays incident on the fourth area Ar4.

[0106] That is, step S1 corresponds to the positional relationship adjusting step, the scintillator arranging step, and the imaging device arranging step of the present invention, as well as the X-ray shielding member arranging step.

[0107] Considering the diameter of the defect DE, the X-axis direction in the third region Ar3 ( Figure 5 The length dimension in the left-right direction (in the middle) is preferably set to 30 μm or more and 500 μm or less.

[0108] According to the second embodiment described above, in addition to the same effects as those of the first embodiment, the following effects are also achieved.

[0109] Figure 6 This is a diagram for explaining the effect of Embodiment 2. Specifically, Figure 6 The positional relationship among the X-ray shielding member 8, the scintillator 4 and the imaging device 5 is shown. Figure 6 In FIG. 1 , a circle indicated by a symbol “VL” represents visible light converted by the scintillator 4 from X-rays.

[0110] For example, it is assumed that the visible light in the region ArS1 and the region ArS2 includes the visible light VL (in Figure 6 In addition to the X-rays that have not passed through the defect DE, the scintillator 4 also includes the visible light VL' (indicated by the solid circle in FIG. Figure 6In this case, the brightness of the visible light VL is extinguished by the brightness of the visible light VL', making it difficult to estimate the characteristic amount of the defect DE with high accuracy.

[0111] Therefore, the X-ray inspection device 1A of the second embodiment further includes an X-ray shielding member 8, which shields X-rays incident on the fourth area Ar4 in the entire area of ​​the incident surface 41. That is, the visible light VL' is prevented from being generated by configuring the X-ray shielding member 8. Therefore, the characteristic amount of the defect DE can be estimated with high accuracy.

[0112] (Implementation 3)

[0113] Next, the third embodiment will be described.

[0114] In the following description, the same reference numerals are used for the same structures as those in the first embodiment, and the detailed description thereof will be omitted or simplified.

[0115] Figure 7 is corresponding to Figure 1 , and is a diagram showing an X-ray inspection apparatus 1B according to Embodiment 3. Figure 7 In the figure, for the convenience of explanation, the illustration of the conveying device 3, the imaging device 5, the display device 6, and the control device 7 is omitted.

[0116] In the X-ray inspection apparatus 1B of the third embodiment, as shown in FIG. Figure 6 As shown, compared with the X-ray inspection apparatus 1 described in the first embodiment, a scintillator 4B having a shape different from that of the scintillator 4 is adopted.

[0117] like Figure 7 As shown, the scintillator 4B includes a plate body having a rectangular shape in a plan view, and is arranged on the -Z axis side with respect to the measuring object OB with the plate surface being substantially parallel to the XZ plane.

[0118] Here, in the scintillator 4B, the +Z axis side ( Figure 7 The end face (upper side in the figure) is used for X-rays passing through the measurement object OB to enter, and corresponds to the incident face 41B of the present invention. Figure 7 The plate surface of the scintillator 4B (right side in the figure) intersects with the incident surface 41B, which corresponds to the first side surface 42B of the present invention. Figure 7 The plate surface (left side in the figure) is in a front-back relationship with the first side surface 42B, which is equivalent to the second side surface 43B of the present invention.

[0119] The X-ray inspection method of the third embodiment is the same as the X-ray inspection method described in the first embodiment.

[0120] That is, in step S1, the operator sets the boundary BO ( Figure 7 ) is located in the radiation range SP of X-rays ( Figure 7 ) and configure the scintillator 4B.

[0121] Here, considering the diameter of the defect DE, the thickness dimension between the first side surface 42B and the second side surface 43B in the scintillator 4B is preferably set to be greater than 30 μm and less than 500 μm. In addition, in order to obtain the light receiving amount distribution in step S5, the Z-axis direction ( Figure 7 The length dimension in the Y-axis direction (in the vertical direction) of the scintillator 4B is preferably 200 μm or more. Figure 7 The length dimension in the direction perpendicular to the paper surface) is about 60mm to 100mm.

[0122] According to the third embodiment described above, in addition to the same effects as those of the first embodiment, the following effects are also achieved.

[0123] Figure 8 This is a diagram for explaining the effect of the third embodiment. Specifically, Figure 8 4B and the imaging device 5. Figure 8 In the figure, the circle indicated by the symbol "VL" is Figure 6 Similarly, visible light is shown by converting X-rays into visible light by the scintillator 4B.

[0124] In the X-ray inspection apparatus 1B of the third embodiment, the thickness dimension between the first side surface 42B and the second side surface 43B of the scintillator 4B is set to be greater than or equal to 30 μm and less than or equal to 500 μm.

[0125] Therefore, it is possible to prevent the generation of visible light VL' (at Figure 8 The X-rays transmitted through the defect DE are converted into visible light VL by the scintillator 4B (in Figure 8 Therefore, similarly to the second embodiment, the characteristic amount of the defect DE can be estimated with high accuracy.

[0126] (Other embodiments)

[0127] Although the modes for carrying out the present invention have been described above, the present invention should not be limited to only the first to third embodiments described above.

[0128] In the first to third embodiments, the measuring object OB is imaged by the imaging device 5 while being transported, but the present invention is not limited thereto. The transport device 3 may temporarily stop transporting the measuring object OB only when the imaging device 5 is imaging in the transport step S2.

[0129] In addition, in the first to third embodiments, the transport device 3 transports (moves) the measurement object OB in the transport step S2, but the present invention is not limited thereto. The transport device 3 only needs to move the measurement object OB in the substantially vertical direction of the first side surface 42 relative to the X-ray radiation device 2, the scintillator 4 (4B), and the imaging device 5 in the transport step S2, or the X-ray radiation device 2, the scintillator 4 (4B), and the imaging device 5 may be moved without moving the measurement object OB.

[0130] Fig. 9 These are diagrams for explaining modified examples of the first to third embodiments.

[0131] In the above-mentioned embodiments 1 to 3, in the scintillator 4 (4B), as Fig. 9 As shown in (a), the incident surface 41 and the first side surface 42 intersect in a manner orthogonal to each other, but the present invention is not limited thereto. Fig. 9 As shown in (b), the incident surface 41 and the first side surface 42 intersect at an obtuse angle. Fig. 9 As shown in (c) of FIG. 4 , the corner portion of the incident surface 41 and the first side surface 42 is chamfered. Fig. 9 As shown in (d), the corner portion between the incident surface 41 and the first side surface 42 is R-chamfered.

[0132] Explanation of symbols

[0133] 1.1A, 1B: X-ray inspection equipment

[0134] 2: X-ray radiation device

[0135] 3: Transport device

[0136] 4.4B: Scintillator

[0137] 5: Shooting device

[0138] 6: Display device

[0139] 7: Control device

[0140] 8: X-ray shielding components

[0141] 21: X-ray focus

[0142] 41, 41B: Incident surface

[0143] 42, 42B: First side

[0144] 43B: Second side

[0145] 71: Processor

[0146] 72: Storage

[0147] 73: Input

[0148] Ar1: First area

[0149] Ar2: Second area

[0150] Ar3: The third area

[0151] Ar4: The fourth area

[0152] ArS1, ArS2: Area

[0153] BO: Border

[0154] DE: Defect

[0155] F1, F2: X-ray images

[0156] L1, L2: distance

[0157] OB: Object of measurement

[0158] r: width

[0159] SH: Penumbra

[0160] SP: Radiation range

[0161] VL, VL': visible light

Claims

1. An X-ray inspection device, characterized in that: include: An X-ray radiating device radiates X-rays toward a measurement object; a scintillator that converts the X-ray incident through the measurement object into visible light; as well as an imaging device that captures the visible light from the scintillator to generate an X-ray image, Wherein, the scintillator is: The X-rays are arranged so that a boundary between an incident surface on which the X-rays are incident and a first side surface intersecting the incident surface is located within a radiation range of the X-rays. The photographing device is: When the entire area of ​​the first side surface is divided into two areas, namely, a first area including the boundary and a second area excluding the first area, it is configured to face the first side surface, and the visible light emitted from the first area in the entire area of ​​the first side surface is photographed.

2. The X-ray inspection device according to claim 1, characterized in that: Also includes: An X-ray shielding component is arranged between the measurement object and the scintillator when the entire area of ​​the incident surface is divided into two areas, namely a third area including the boundary and a fourth area excluding the third area, and the X-ray shielding component shields the X-rays incident on the fourth area in the entire area of ​​the incident surface.

3. The X-ray inspection device according to claim 1, characterized in that: In the scintillator, The dimension between the second side surface that is the front and back surface of the first side surface and the first side surface is set to be 30 μm or more and 500 μm or less.

4. The X-ray inspection device according to claim 1, characterized in that: Also includes: an image analyzing device for analyzing the X-ray image, The image analysis device is: Based on the brightness distribution of the visible light along the incident direction of the X-ray in the X-ray image, a feature amount of an abnormal part present in the measurement object is estimated.

5. The X-ray inspection device according to claim 1, characterized in that: The X-ray radiating device and the scintillator are: The X-ray radiation device is configured so that when the distance from the X-ray focus to the measurement object is set to L1 [mm], the distance from the X-ray focus to the scintillator is set to L2 [mm], and the diameter of the X-ray focus is set to R [μm], the width of the penumbra represented by (L2-L1)×R / L1 becomes less than 30 μm.

6. The X-ray inspection device according to claim 1, characterized in that: Also includes: A transport device that moves the measurement object relative to the X-ray irradiation device, the scintillator, and the imaging device in a direction approximately perpendicular to the first side surface, or repeatedly performs the relative movement and stop.

7. An X-ray inspection method, characterized in that: include: a scintillator disposing step of disposing the scintillator in such a manner that a boundary between an incident surface on which X-rays are incident and a first side surface intersecting the incident surface is located within an X-ray radiation range; a photographing device disposing step of disposing the photographing device so as to face the first side surface; An X-ray irradiation step of irradiating the X-rays from an X-ray irradiation device toward the measurement object; as well as an imaging step of imaging the X-rays passing through the measurement object and entering the scintillator and converted into visible light by the scintillator, thereby generating an X-ray image, In the shooting process, When the entire area of ​​the first side surface is divided into two areas, namely, a first area including the boundary and a second area excluding the first area, the visible light emitted from the first area in the entire area of ​​the first side surface is photographed by the photographing device.

8. The X-ray inspection method according to claim 7, characterized in that: Also includes: An X-ray shielding component configuration process, in which, when the entire area of ​​the incident surface is divided into two areas, namely, a third area including the boundary and a fourth area excluding the third area, in order to shield the X-rays incident on the fourth area, the X-ray shielding component configuration process configures an X-ray shielding component for shielding the X-rays between the measured object and the scintillator.

9. The X-ray inspection method according to claim 7, characterized in that: Also includes: an image analysis step of analyzing the X-ray image, In the image analysis step, Based on the brightness distribution of the visible light along the incident direction of the X-ray in the X-ray image, a feature amount of an abnormal part present in the measurement object is estimated.

10. The X-ray inspection method according to claim 7, characterized in that: Also includes: a positional relationship adjustment step of adjusting the positional relationship between the X-ray irradiation device and the scintillator, In the positional relationship adjustment step, The positional relationship between the X-ray radiation device and the scintillator is adjusted in such a way that the width of the penumbra represented by (L2-L1)×R / L1 becomes less than 1 / 6 of the diameter of the defect to be detected relative to the measuring object when the distance from the X-ray focus of the X-ray radiation device to the measuring object is set to L1 [mm], the distance from the X-ray focus to the scintillator is set to L2 [mm], and the diameter of the X-ray focus is set to R [μm].

11. The X-ray inspection method according to claim 7, characterized in that: Also includes: A transporting step in which the measurement object is relatively moved relative to the X-ray irradiation device, the scintillator, and the imaging device in a direction substantially perpendicular to the first side surface, or the relative movement and stopping are repeated.

Images