X-ray inspection device

Abstract

The invention relates to an X-ray inspection apparatus. An X-ray inspection apparatus includes: a transport unit that transports an article; an irradiation unit that irradiates X-rays to the article conveyed by the conveyance unit; a sensor unit in which a plurality of detection elements for detecting X-rays are arranged in a planar shape; an image generation unit that reads detection results output from at least some of the plurality of detection elements at predetermined time intervals and generates an image; and a time setting unit for setting a predetermined time, the time setting unit multiplying the predetermined time by a magnification set according to the conveyance speed of the conveyance unit or the detection result.

Description

Technical Field

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

[0002] In the past, as a device for inspecting inspected objects (articles) such as food and medicines, an inspection device using electromagnetic waves such as X-rays was used. For example, the article inspection device described in Japanese Patent Publication No. 2021-156635 includes an irradiation unit and a detection unit, the irradiation unit irradiates electromagnetic waves that spread radially to the moving inspected object, and the detection unit detects the electromagnetic waves affected by the inspected object through multiple detection elements. The article inspection device includes a delay time setting unit and a TDI image generation unit, the delay time setting unit sets multiple delay times according to a specified reference delay time, and the TDI image generation unit performs a time delay integration process to generate multiple TDI images (time delay integration images) corresponding to the multiple delay times, and the time delay integration process is a process of adding the detection data detected by the detection unit using multiple delay times. The user of the above-mentioned article inspection device uses a favorable TDI image among the multiple TDI images generated according to the multiple delay times to perform a good or bad judgment of the inspected object. Summary of the invention

[0003] In the above-mentioned article inspection device, the actual conveying speed of the conveying unit for the inspected object is independent of the setting of the predetermined reference delay time and the plurality of delay times. Therefore, it is difficult to appropriately set the delay time corresponding to the conveying speed of the inspected object. In such an article inspection device, the detection result output from the detection unit is not good according to the actual conveying speed, and as a result, it may not be possible to accurately determine whether the inspected object is good or bad.

[0004] An object of one aspect of the present invention is to provide an X-ray inspection apparatus capable of performing good inspection regardless of the transport speed.

[0005] Technical solutions to solve problems

[0006] (1) An X-ray inspection apparatus according to one aspect of the present invention comprises: a conveying unit for conveying an article; an irradiating unit for irradiating the article conveyed by the conveying unit with X-rays; a sensor unit having a plurality of detection elements arranged in a plane for detecting X-rays; an image generating unit for reading detection results outputted from at least a part of the plurality of detection elements at intervals of a prescribed time and generating an image; and a time setting unit for setting a prescribed time, the time setting unit multiplying the prescribed time by a magnification set according to a conveying speed of the conveying unit or a detection result.

[0007] According to the X-ray inspection device, the time setting unit multiplies the prescribed time by a magnification set according to the conveying speed of the conveying unit or the detection results output from at least a part of the multiple detection elements. For example, in the case where the conveying speed of the conveying unit is too fast, the output of at least a part of the multiple detection elements is too low and the detection results are insufficient, the time setting unit multiplies the prescribed time by a magnification greater than 1. In this case, the interval (delay time) of the prescribed time for the image generation unit to read the detection results output from the sensor unit is extended. By extending the above-mentioned delay time for some reason, the period during which each detection element is exposed to X-rays (X-ray exposure period) can be appropriately adjusted. Therefore, by using the above-mentioned X-ray inspection device, the detection results output from each detection element become good, so a good inspection can be carried out regardless of the conveying speed.

[0008] (2) In the X-ray inspection apparatus described in (1) above, the sensor unit may increase or decrease the number of detection elements to be operated according to a conveying speed or a detection result. In this case, an X-ray exposure period for each detection element can be reliably ensured.

[0009] (3) In the X-ray inspection apparatus described in (1) or (2) above, the sensor unit may detect X-rays by a photon counting method. In this case, the contrast of the image generated by the image generating unit can be improved.

[0010] (4) In the X-ray inspection device described in any one of (1) to (3), the time setting unit may multiply the predetermined time by the inverse of the ratio of the detection elements in operation among the plurality of detection elements. In this case, the X-ray exposure period of each detection element in operation can be reliably ensured.

[0011] (5) In the X-ray inspection apparatus described in any one of (1) to (4) above, when the conveying speed is faster than the prescribed speed, the time setting unit may multiply the prescribed time by a factor set to a natural number. In this case, since the delay time can be sufficiently extended, the contrast of the image generated by the image generating unit can be further improved.

[0012] (6) In the X-ray inspection device described in any one of (1) to (5) above, when the maximum intensity of the detection signal included in the detection result is lower than a predetermined intensity, the time setting unit may multiply the predetermined time by a factor set to a natural number. In this case, since the delay time can be sufficiently extended, the contrast of the image generated by the image generating unit can be further improved.

[0013] (7) In the X-ray inspection device described in any one of (1) to (6) above, when the magnification is greater than 1 and the maximum intensity of the detection signal included in the detection result is higher than a predetermined intensity, the time setting unit sets the magnification to 1. In this case, the contrast of the image generated by the image generating unit can be further improved.

[0014] (8) In any one of the above (1) to (7), the X-ray inspection device may further include a determination unit that determines whether or not a foreign object is present in an object including food based on an image. Therefore, even if the output of X-rays is suppressed, the determination unit can well determine whether or not a foreign object is present.

[0015] (Effects of the Invention)

[0016] According to one aspect of the present invention, it is possible to provide an X-ray inspection apparatus capable of performing good inspection regardless of the transport speed. BRIEF DESCRIPTION OF THE DRAWINGS

[0017] Figure 1 This is a diagram showing the configuration of an X-ray inspection apparatus according to one embodiment.

[0018] Figure 2 yes Figure 1 The schematic diagram of the internal structure of the shielding box shown.

[0019] Figure 3 Schematic diagram showing detection elements in operation and detection elements not used for image generation.

[0020] Figure 4 This is a functional configuration diagram of the control unit.

[0021] Description of Reference Numerals

[0022] 1…X-ray inspection device, 3…support leg, 4…shielding box, 4a…input port, 4b…output port, 5…conveying unit, 6…X-ray irradiation unit, 7…sensor unit, 8…display operation unit, 10…control unit, 11…detection element, 21…receiving unit, 22…time setting unit, 23…image generating unit, 24…inspection unit, 25…judgment unit, 26…output unit, 27…recording unit, A…conveying direction, G…article. DETAILED DESCRIPTION

[0023] Hereinafter, preferred embodiments of the present invention will be described in detail with reference to the accompanying drawings. In the description of the drawings, the same or corresponding elements are denoted by the same reference numerals, and duplicate descriptions are omitted.

[0024] like Figure 1As shown, the X-ray inspection device 1 includes a device body 2, a support leg 3, a shield box 4, a conveyor 5, an X-ray irradiation unit 6, a sensor unit 7, a display operation unit 8, and a control unit 10. The X-ray inspection device 1 generates an X-ray transmission image of the article G while conveying the article G, and inspects the article G based on the X-ray transmission image. The article G before inspection is input into the X-ray inspection device 1 through an input conveyor 51. The inspected article G is output from the X-ray inspection device 1 through an output conveyor 52.

[0025] The device body 2 accommodates the control unit 10 and the like. The support legs 3 support the device body 2. The shielding box 4 is provided in the device body 2. The shielding box 4 is a shell that prevents X-rays (electromagnetic waves) from leaking to the outside. An inspection room R for inspecting the article G using X-rays is provided inside the shielding box 4. An input port 4a and an output port 4b are formed in the shielding box 4. The article G before inspection is input into the inspection room R from the input conveyor 51 via the input port 4a. The article G after inspection is output from the inspection room R to the output conveyor 52 via the output port 4b.

[0026] The conveying unit 5 is a component for conveying the article G, and is arranged in a manner that passes through the center of the shielding box 4. The conveying unit 5 conveys the article G along the conveying direction A from the input port 4a through the inspection room R to the output port 4b. The speed (conveying speed) at which the article G is conveyed by the conveying unit 5 is set by, for example, the control unit 10. The conveying unit 5 is, for example, a belt conveyor installed between the input port 4a and the output port 4b. In addition, the conveying unit 5 may also protrude further outward than the input port 4a and the output port 4b.

[0027] like Figure 1 and Figure 2 As shown, the X-ray irradiation unit 6 is an electromagnetic wave irradiation unit arranged in the shield box 4, and irradiates X-rays to the article G transported by the conveyor 5. The X-rays include X-rays in various energy ranges from low energy (long wavelength) to high energy (short wavelength). Therefore, the X-ray irradiation unit 6 irradiates the article G transported by the conveyor 5 with X-rays in multiple energy ranges. It is also possible to implement X-ray irradiation by the X-ray irradiation unit 6 after the X-ray inspection device 1 is started and before the article G is inspected (that is, the X-ray irradiation unit 6 is idle). In addition, the "low" and "high" in the above-mentioned low energy and high energy represent relatively "low" and "high" in the multiple energy ranges irradiated from the X-ray irradiation unit 6, and do not represent a specific range. In addition, the power (especially the current) supplied to the X-ray irradiation unit 6 can be changed manually or automatically. By changing the power, the output of the X-ray irradiated to the article G can be changed. In this way, X-rays with an appropriate intensity corresponding to the article G can be irradiated.

[0028] The sensor unit 7 is a sensor unit that detects electromagnetic waves. The sensor unit 7 is arranged in the shield box 4 at a position opposite to the X-ray irradiation unit 6 in the up-down direction. The sensor unit 7 has a plurality of detection elements 11 arranged in a planar (two-dimensional) manner. The detection elements 11 are arranged at least in a direction (width direction) orthogonal to the conveying direction A and the up-down direction of the conveying unit 5. A line sensor may also be formed by a part of the plurality of detection elements 11 in the sensor unit 7. For example, in the sensor unit 7, a plurality of line sensors extending in the above-mentioned width direction may be arranged along the conveying direction A. In this case, the plurality of line sensors respectively include a plurality of detection elements 11 arranged in the above-mentioned width direction. In addition, unless otherwise specifically mentioned below, the plurality of detection elements 11 are equivalent to all the detection elements 11 included in the sensor unit 7.

[0029] In the present embodiment, the sensor unit 7 is a direct conversion type detection unit capable of detecting X-rays by photon counting. In addition, the detection element 11 is, for example, a sensor (multi-energy sensor) that detects X-rays in each of a plurality of energy regions that pass through the article G, and the sensor unit 7 may also be a time delay integration sensor (TDI sensor: Time Delay Integration sensor). The detection element 11 includes, for example, a photon detection type sensor such as a CdTe semiconductor detector. In the detection element 11, for example, electron-hole pairs are generated by the arrival of photons of X-rays. Photon counting processing (photon counting) is performed according to the energy (photon energy) obtained at this time. The counting processing is implemented, for example, by a calculation unit (not shown) included in the sensor unit 7 or the detection element 11. The result of the above-mentioned counting processing (detection result) of each detection element 11 implemented by the calculation unit is output to the control unit 10, for example, at intervals of a specified time. The specified time is a time (default time) pre-specified by the X-ray inspection device 1. In addition, the interval of the above-mentioned specified time is also called a readout interval or a delay time, and can be appropriately changed by the control unit 10 (described in detail later).

[0030] Each detection element 11 of the sensor unit 7 can also distinguish the photon energy of the detected X-ray into two or more energy regions according to an arbitrary threshold value. In this case, the sensor unit 7 can count the photons in each energy region. The arbitrary threshold value is, for example, one or more values ​​(unit: keV) set by the control unit 10. The arbitrary threshold value can be set, for example, by the method described in Japanese Patent Application Laid-Open No. 2023-132587, or can be set using the following brightness level.

[0031] When the X-ray inspection device 1 is started, the sensitivity calibration (calibration) of the sensor unit 7 can be performed. In this sensitivity calibration, the brightness level is obtained based on the X-ray that has not passed through the article G. The brightness level is the number of photon counts detected when the X-ray that has not passed through the article G enters the sensor unit 7, and is equivalent to the intensity of the detection signal included in the above detection result. The sensitivity calibration of the sensor unit 7 is equivalent to the correction of the output difference between the detection elements 11 included in the sensor unit 7. From the viewpoint of shortening the startup time of the X-ray inspection device 1, in the above sensitivity calibration, the X-ray irradiation unit 6 may start irradiating X-rays at the same time as the sensor unit 7 starts detecting X-rays. In addition, the sensitivity calibration of the sensor unit 7 is performed by the method described in Japanese Patent Application No. 2023-39353, for example. In this embodiment, from the viewpoint of improving the contrast of the image generated by the X-ray inspection device 1, it is confirmed whether the highest brightness level obtained in the sensitivity calibration is lower than a predetermined threshold value. That is, it is confirmed whether the maximum intensity of the detection signal included in the above detection result output from at least a part of the plurality of detection elements 11 obtained in the sensitivity calibration is lower than a predetermined intensity. The result of this confirmation is output to the control unit 10 .

[0032] The sensor unit 7 may increase or decrease the number of the detection elements 11 that operate according to the conveying speed of the conveying unit 5 , the above-mentioned detection results, and the like. Figure 3 Schematic diagram showing detection elements in operation and detection elements not used for image generation. Figure 3 , a portion of the detection elements 11 included in the sensor unit 7 is shown, and the detection elements 11 in operation (the detection elements 11 used to generate images) are marked with "○", and the detection elements 11 not used to generate images are marked with "×". For example, when the above-mentioned conveying speed is too high to output a good detection result from all the detection elements 11, when the above-mentioned maximum intensity obtained in the sensitivity calibration is lower than the specified intensity, etc., Figure 3As shown, the sensor unit 7 limits the number of detection elements 11 in operation. Thus, good detection results can be output from all the detection elements 11 in operation. The detection elements 11 to be limited are selected according to a predetermined rule, pattern, etc. The rule, pattern, etc. can also be appropriately changed according to the type of the article G, the accumulated operation time of the X-ray inspection device 1, etc. For example, when only a part of the detection elements 11 included in the sensor unit 7 is in operation, the detection elements 11 in operation can be always the same or can be appropriately changed. On the other hand, when the sensor unit 7 limits the number of detection elements 11 in operation, when the above-mentioned conveying speed is no longer too high, etc., the sensor unit 7 releases the limit on the number of detection elements 11 in operation. Thus, the number of detection elements 11 in operation increases. In addition, when the above-mentioned plurality of line sensors are arranged in the sensor unit 7, the sensor unit 7 can also limit the number of line sensors in operation. In this case, the control of the detection elements 11 by the sensor unit 7 can be simplified. When the sensor unit 7 limits the number of detection elements 11 in operation, the plurality of line sensors may be operated at intervals of one or two in the conveying direction A. In addition, in the present embodiment, the sensor unit 7 changes the number of detection elements 11 in operation, but the present invention is not limited thereto. The number of detection elements 11 in operation may also be changed manually, for example.

[0033] like Figure 1 As shown, the display operation unit 8 is a component (display unit) provided in the device body 2. The display operation unit 8 displays various information and accepts input operations of various conditions from the outside. The display operation unit 8 is, for example, a liquid crystal display, and displays an operation screen as a touch panel. In this case, the operator can input various conditions via the display operation unit 8. For example, the operator can set the conveying speed of the conveying unit 5, the power (at least one of the current and the voltage) supplied to the X-ray irradiation unit 6, the number of detection elements 11 to be operated, etc. via the display operation unit 8. The input operation accepted by the display operation unit 8 is output to the conveying unit 5, the sensor unit 7, the control unit 10, etc.

[0034] The control unit 10 is disposed inside the apparatus body 2. The control unit 10 controls the operation of each unit of the X-ray inspection apparatus 1. The control unit 10 is composed of a CPU (Central Processing Unit), a ROM (Read Only Memory), a RAM (Random Access Memory), etc. The ROM stores a program for controlling the X-ray inspection apparatus 1, an operation mode of the X-ray inspection apparatus 1, etc.

[0035] Figure 4This is the functional structure diagram of the control unit. Figure 4 As shown, the control unit 10 includes a receiving unit 21 , a time setting unit 22 , an image generating unit 23 , an inspecting unit 24 , a determining unit 25 , an output unit 26 , and a recording unit 27 .

[0036] The receiving unit 21 receives an input operation accepted by the display operation unit 8. The receiving unit 21 sends, for example, the conveying speed of the conveying unit 5 and the number of operating detection elements 11 set via the display operation unit 8 to the time setting unit 22. In addition, the receiving unit 21 receives the detection result output from the sensor unit 7. The receiving unit 21 sends the received detection result to the image generating unit 23.

[0037] The time setting unit 22 sets a reading interval (i.e., a predetermined time) at which the image generating unit 23 reads out the detection result. The time setting unit 22 can change the reading interval by multiplying the predetermined time by a magnification set according to the operation state of the X-ray inspection device 1, etc. In the present embodiment, the time setting unit 22 multiplies the predetermined time by a magnification set according to the conveying speed or the detection result. The magnification may be 1, or a natural number multiple of 2 or more, or any multiple greater than 1. For example, in the case where the conveying speed is faster than the predetermined speed, or the highest brightness level obtained in the sensitivity correction is lower than the predetermined threshold value (the maximum intensity of the detection signal obtained in the sensitivity correction is lower than the predetermined intensity), the time setting unit 22 multiplies the predetermined time by a magnification set to a natural number multiple. Alternatively, the time setting unit 22 may multiply the predetermined time by a magnification set to an arbitrary multiple greater than 1 (for example, 1.25, 1.4, 1.6, or 1.75). By multiplying the above-mentioned predetermined time by the above-mentioned magnification by the time setting unit 22, the above-mentioned readout interval can be changed. In addition, the time setting unit 22 can also set the magnification to 1 times when the above-mentioned magnification is greater than 1 times and the above-mentioned maximum intensity is higher than the predetermined intensity. In this way, the occurrence of accumulation in the sensor unit 7 can be suppressed. Regardless of the change of the above-mentioned readout interval, the period required for the above-mentioned calculation unit included in the sensor unit 7 or the detection element 11 to perform the counting process is constant. Therefore, regardless of the conveying speed of the conveying unit 5, etc., it is sufficient to change the above-mentioned readout interval so that the ratio of the X-ray exposure period of each detection element 11 in the above-mentioned readout interval becomes greater than the predetermined value.

[0038] In the case where the transport speed is faster than the prescribed speed, or the maximum intensity of the detection signal included in the detection result is lower than the prescribed intensity, the readout interval and the number of the detection elements 11 in operation by the sensor unit 7 may both be changed. In this case, the multiplication factor multiplied by the prescribed time may have a certain correlation with the ratio of the detection elements 11 in operation among the plurality of detection elements 11. For example, from the viewpoint of simplifying the operation control of the X-ray inspection apparatus 1, when the sensor unit 7 limits the number of the detection elements 11 in operation, the time setting unit 22 may multiply the prescribed time by the inverse of the ratio of the detection elements 11 in operation among the plurality of detection elements 11. For example, when half of the detection elements 11 in all the detection elements 11 are in operation (that is, when the ratio is 0.5 times), the time setting unit 22 may double the prescribed time.

[0039] The image generation unit 23 is mainly composed of a GPU (Graphics Processing Unit), for example, and expands the detection result signal into a two-dimensional image on a memory. The memory for expanding the two-dimensional image is, for example, a memory included in the GPU, but is not limited thereto. The image generation unit 23 reads the detection result output from at least a part of the multiple detection elements 11 included in the sensor unit 7 at the above-mentioned readout interval, and generates one or more time-delayed integrated images for inspecting the object G. For example, the image generation unit 23 generates a plurality of transmission images corresponding to the above-mentioned multiple energy regions. In addition, the image generation unit 23 can also generate one or more differential images based on the multiple transmission images. The image generation unit 23 can use an image processing algorithm, for example, or a program automatically set by machine learning. The image processing algorithm is composed of one image processing filter or a combination of multiple image processing filters. At least one or more of the multiple image processing algorithms can be automatically generated from multiple image processing filters according to the specifications or inspection conditions of the X-ray inspection device 1 using a genetic algorithm (GA). The genetic algorithm is a method that applies the mechanism of inheritance and evolution in the biological world. At least a part of the plurality of image processing algorithms may also be appropriately set by the operator via the display operation unit 8. The program automatically set by machine learning is a prediction model (learned model) generated by machine learning, and is an inference program in which parameters (learned parameters) obtained from the results of machine learning are embedded. Examples of machine learning used in the learned model include neural networks, support vector machines, genetic algorithms, and the like.

[0040] The inspection unit 24 inspects the article G based on the image generated by the image generating unit 23. For example, the inspection unit 24 inspects the article G using the above-mentioned multiple transmission images, the above-mentioned differential image, etc. The inspection unit 24 may inspect the article G based on both the differential image and the transmission image. The article G may also be inspected based on the transmission image, etc., during the period when the differential image is generated by the image generating unit 23. The inspection unit 24 inspects the article G for, for example, the presence of foreign matter, cracks, and defects, but is not limited thereto. In the case where the article G is wrapped in a sheet-like packaging material, the inspection unit 24 may also inspect the damage of the packaging material, the poor sealing of the packaging material (sealing bite), etc. In the case where the article G is stored in a packaging body, the inspection unit 24 may perform a foreign matter confirmation check, a missing product confirmation check, a storage number confirmation check, a void confirmation check, etc. in the packaging body. The inspection unit 24 sends the inspection result of the article G to the determination unit 25 and the recording unit 27.

[0041] The determination unit 25 determines whether the article G is a good product based on the inspection result received from the inspection unit 24. For example, the determination unit 25 determines whether there is foreign matter in the article G, whether the article G has cracks or defects, etc. The determination unit 25 sends the determination result to the output unit 26 and the recording unit 27.

[0042] The output unit 26 outputs the determination result of the determination unit 25 to at least one of a portion other than the control unit 10 in the X-ray inspection apparatus 1 and a device different from the X-ray inspection apparatus 1. Thus, at least one of the X-ray inspection apparatus 1 and a device different from the X-ray inspection apparatus 1 (for example, a distribution device arranged at a position downstream of the X-ray inspection apparatus 1) can perform an action when the article G is a defective article. As another example of the above-mentioned device different from the X-ray inspection apparatus 1, for example, the input conveyor 51, the output conveyor 52, the notification device, etc. can be cited.

[0043] The recording unit 27 records signals, data, and the like generated by the control unit 10. For example, the recording unit 27 records the detection result sent from the receiving unit 21, the image data sent from the image generating unit 23, the data related to the inspection result sent from the inspection unit 24, and the data related to the determination result sent from the determination unit 25.

[0044] According to the X-ray inspection device 1 of the present embodiment described above, the time setting unit 22 multiplies the above-mentioned predetermined time by a magnification set according to the conveying speed of the conveying unit 5 or the detection result output from at least a part of the plurality of detection elements 11. For example, in the case where the conveying speed of the conveying unit 5 is too fast, or the output of at least a part of the plurality of detection elements 11 is too low and the detection result is insufficient, the time setting unit 22 multiplies the predetermined time by a magnification greater than 1. In this case, the readout interval at which the image generating unit 23 reads out the detection result output from the sensor unit 7 is extended. By extending the readout interval for some reason, the X-ray exposure period of each detection element 11 can be adjusted to an appropriate period. Therefore, by using the X-ray inspection device 1 of the present embodiment, the detection result output from each detection element 11 becomes good, so that a good inspection can be performed regardless of the conveying speed of the conveying unit 5.

[0045] Here, in the present embodiment, the magnification is automatically set according to the conveying speed or the detection result. In addition, the time setting unit 22 automatically multiplies the predetermined time by the magnification. Therefore, the operator of the X-ray inspection device 1 can automatically set an appropriate reading interval (delay time) based on the conveying speed, the detection result, etc. without performing special settings, operations, etc. Therefore, even a simple user of the X-ray inspection device 1 can perform a good inspection regardless of the conveying speed of the conveyor 5.

[0046] In this embodiment, the sensor unit 7 may increase or decrease the number of operating detection elements 11 according to the conveying speed or the detection result. In this case, the X-ray exposure period of each detection element 11 can be reliably ensured.

[0047] In this embodiment, the sensor unit 7 may detect X-rays by photon counting. In this case, the contrast of the image generated by the image generating unit 23 can be improved.

[0048] In this embodiment, the time setting unit 22 may multiply the predetermined time by the inverse of the ratio of the operating detection elements 11 among the plurality of detection elements 11. In this case, the X-ray exposure period of each operating detection element 11 can be reliably ensured.

[0049] In this embodiment, when the conveying speed is faster than the predetermined speed, the time setting unit 22 may multiply the predetermined time by a factor set to a natural number. In this case, since the delay time can be sufficiently extended, the contrast of the image generated by the image generating unit 23 can be further improved.

[0050] In this embodiment, when the maximum intensity of the detection signal included in the detection result is lower than the specified intensity, the time setting unit 22 may multiply the specified time by a factor set to a natural number. In this case, since the delay time can be sufficiently extended, the contrast of the image generated by the image generating unit 23 can be further improved.

[0051] In this embodiment, when the magnification is greater than 1 and the maximum intensity of the detection signal included in the detection result is higher than the predetermined intensity, the time setting unit 22 may set the magnification to 1. In this case, the contrast of the image generated by the image generating unit 23 can be further improved.

[0052] In the present embodiment, the X-ray inspection apparatus 1 includes the determination unit 25 that determines the presence or absence of foreign matter in the article G including food based on the image. Therefore, even if the output of X-rays is suppressed, the determination unit 25 can satisfactorily determine the presence or absence of foreign matter.

[0053] The embodiments of the present invention are described above, but the present invention is not limited to the above embodiments, and various changes can be made without departing from the scope of the present invention. For example, in the above embodiments, the sensor unit is a device that can detect X-rays using a photon counting method, but it is not limited to this. The detection element included in the sensor unit may also have at least a scintillator and a photodiode.

Claims

1. An X-ray inspection device comprising: Conveying department, conveying items; an irradiation unit, irradiating the article transported by the transport unit with X-rays; A sensor unit having a plurality of detection elements arranged in a plane for detecting the X-rays; an image generating unit that reads out detection results output from at least a part of the plurality of detection elements at predetermined time intervals and generates an image; as well as A time setting unit is configured to set the specified time. The time setting unit multiplies the predetermined time by a magnification factor set according to a conveying speed of the conveying unit or the detection result.

2. The X-ray inspection apparatus according to claim 1, wherein: The sensor unit increases or decreases the number of the detection elements that operate according to the conveying speed or the detection result.

3. The X-ray inspection device according to claim 1 or 2, wherein: The plurality of detection elements detect the X-rays using a photon counting method.

4. The X-ray inspection apparatus according to claim 1 or 2, wherein: The time setting unit multiplies the predetermined time by the inverse of the ratio of the detection elements in operation among the plurality of detection elements.

5. The X-ray inspection apparatus according to claim 1 or 2, wherein: When the conveying speed is faster than a predetermined speed, the time setting unit multiplies the predetermined time by the multiplication factor set to a natural number.

6. The X-ray inspection apparatus according to claim 1 or 2, wherein: When the maximum intensity of the detection signal included in the detection result is lower than a predetermined intensity, the time setting unit multiplies the predetermined time by the multiplication factor set to a natural number.

7. The X-ray inspection apparatus according to claim 1 or 2, wherein: The time setting unit sets the magnification to 1 when the magnification is greater than 1 and the maximum intensity of the detection signal included in the detection result is higher than a predetermined intensity.

8. The X-ray inspection apparatus according to claim 1 or 2, wherein: The X-ray inspection apparatus further includes a determination unit configured to determine whether or not a foreign object is present in the article including food based on the image.

Images