JP2010276409A - X-ray inspection device - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide an X-ray inspection device which simply performs processing up to detection of minute foreign matter and certainly detects the minute foreign matter. <P>SOLUTION: The surface of each of second photodiodes 421 includes an area integral multiple of that of the surface of each of first photodiodes 311. In order to obtain this constitution, a plurality of the second photodiodes 421 are respectively arranged so that the distance L42 of one side in the crossing direction L2 of each of the second photodiodes 421 becomes the integral multiple (e.g., twice) of the distance L32 of one side in the crossing direction L2 of each of the first photodiodes 311. In this case, the size (area) of each of the second photodiodes 421 becomes twice the size (area) of each of the first photodiodes 311. <P>COPYRIGHT: (C)2011,JPO&INPIT

Description

  The present invention relates to an X-ray inspection apparatus that irradiates an article with X-rays and detects foreign matter in the article.

  Conventionally, an X-ray inspection apparatus or the like has been used to detect foreign matter in an article. R & D is being conducted daily on these X-ray inspection apparatuses.

  For example, a nondestructive inspection apparatus in which a pair of second radiation detectors are arranged in parallel with a pair of first radiation detectors interposed therebetween has been proposed (see Patent Document 1).

  In such a non-destructive inspection apparatus, an object to be inspected is sandwiched between a pair of first radiation detectors that react to all radiation and a pair of second radiation detectors that react only to charged particles. Yes. Then, transmission image data of the object to be inspected is acquired from the output signals of the pair of first radiation detectors, radiation selection information is generated from the output signals of the pair of second radiation detectors, and the transmission is performed. The image data is calibrated based on the radiation selection information.

  The first radiation detector described above reacts with charged particles when radiation (such as X-rays) is incident, and guides the incident radiation to the subsequent stage by transmission, for example, a well-known microstrip gas chamber ( MSGC) or multi-wire proportional counting box (MWPC).

JP 2000-206253 A

  However, in the conventional nondestructive inspection apparatus, the radiation transmitted through one of the first radiation detectors is attenuated, so that the attenuated radiation is incident on the other first radiation detector. Therefore, the reliability of the transmission image data acquired based on these output signals is questioned.

  Therefore, it is conceivable that the output of the other first radiation detector is amplified to make the output the same as the output of the first radiation detector. However, the noise is also amplified by the amplification. End up. As a result, the noise of the other first radiation detector becomes larger than the noise of one first radiation detector.

  Therefore, as shown in FIG. 7, in order to solve the problem that the attenuation of the X-ray S1 occurs as described above, the size of each photodiode 940 of the second photodiode array 920 is changed to each of the first photodiode array 910. It is conceivable to make the size larger than the size of the photodiode 930.

  With this configuration, the size of the inspection object KS2 on the output image by the photodiode 940 in FIG. 8B is set to the size of the inspection object KS1 on the output image by the photodiode 930 in FIG. It is possible to match.

  However, in the subsequent processing, the pixel number size G2 of the output image by the photodiode 940 shown in FIG. 8D may be matched with the pixel number size G1 of the output image by the photodiode 930 shown in FIG. However, at this time, the size of the inspection object KS2 becomes smaller than the size of the inspection object KS1. Therefore, the image enlargement process and the compression process for adjusting the sizes of the inspection objects KS1 and KS2 to each other are very complicated and laborious.

  An object of the present invention is to provide an X-ray inspection apparatus that can easily perform processing up to detection of a minute foreign matter and can reliably detect the minute foreign matter.

(1)
An X-ray inspection apparatus according to a first aspect of the present invention is an X-ray inspection apparatus that conveys an object and detects foreign matter in the object, and irradiates the object with X-rays. And a first line sensor and a second line sensor that receive the X-rays emitted from the X-ray irradiation device, the first line sensor being disposed vertically above the second line sensor, The receiving surface that receives X-ray irradiation of the sensor has an area that is an integral multiple of the receiving surface that receives X-ray irradiation of the first line sensor.

  In the X-ray inspection apparatus according to the first invention, the object is irradiated with X-rays by the X-ray irradiation apparatus, and the X-rays are received by the first line sensor and the second line sensor. The first line sensor is disposed vertically above the second line sensor. The receiving surface that receives the X-ray irradiation of the second line sensor has an area that is an integral multiple of the receiving surface that receives the X-ray irradiation of the first line sensor.

  With such a configuration, even when the sizes of the objects on the output images are matched with each other in the processing of the output images obtained by the first line sensor and the second line sensor, the receiving surface of the second line sensor Since the area is an integral multiple of the area of the receiving surface of the first line sensor, image enlargement processing, compression processing, and the like for specifying minute foreign matters are simplified. Therefore, the process up to the detection of the minute foreign matter can be easily performed, and the minute foreign matter can be reliably detected.

(2)
The first line sensor includes a scintillator that performs light conversion and a plurality of first photodiodes, and the second line sensor includes a scintillator that performs light conversion and a plurality of second photodiodes, and the receiving surface of the first line sensor is The surface of the second photodiode is composed of a plurality of first photodiodes, and the receiving surface of the second line sensor is composed of the surfaces of the plurality of second photodiodes. May have an area that is an integer multiple of.

  In this case, since the surface of each second photodiode has an area that is an integral multiple of the surface of each first photodiode, image enlargement processing, compression processing, and the like for identifying minute foreign matters are significantly simplified. Therefore, the work process can be reduced.

(3)
The length of one side of each second photodiode in the conveyance direction of the object may be an integral multiple of the length of one side of each first photodiode in the conveyance direction of the object.

  Even in this case, since the surface of each second photodiode has an area that is an integral multiple of the surface of each first photodiode, the image enlarging process and the compression process for identifying minute foreign matters are significantly simplified. Is done. Therefore, the work process can be reduced.

(4)
The length of one side in the crossing direction intersecting the transport direction in the horizontal plane in the transport direction of the target object of each second photodiode target is the length of one side in the crossing direction of each first photodiode. It may be an integer multiple.

  Even in this case, since the surface of each second photodiode has an area that is an integral multiple of the surface of each first photodiode, the image enlarging process and the compression process for identifying minute foreign matters are significantly simplified. Is done. Therefore, the work process can be reduced.

(5)
An X-ray inspection apparatus according to a second invention is an X-ray inspection apparatus that conveys an object and detects foreign matter in the object, and irradiates the object with X-rays. And a first line sensor and a second line sensor that receive the X-rays emitted from the X-ray irradiation device, the first line sensor being disposed vertically above the second line sensor, At least one of the sensor and the second line sensor is a direct conversion type flat panel detector, and the receiving surface receiving the X-ray irradiation of the second line sensor is an integer of the receiving surface receiving the X-ray irradiation of the first line sensor. The area is twice as large.

  In the X-ray inspection apparatus according to the second invention, the X-ray irradiation apparatus irradiates the object with X-rays, and the first line sensor and the second line sensor receive the X-rays. The first line sensor is disposed vertically above the second line sensor. The receiving surface that receives the X-ray irradiation of the second line sensor has an area that is an integral multiple of the receiving surface that receives the X-ray irradiation of the first line sensor.

  With such a configuration, even when the sizes of the objects on the output images are matched with each other in the processing of the output images obtained by the first line sensor and the second line sensor, the receiving surface of the second line sensor Since the area is an integral multiple of the area of the receiving surface of the first line sensor, image enlargement processing, compression processing, and the like for specifying minute foreign matters are simplified. Therefore, the process up to the detection of the minute foreign matter can be easily performed, and the minute foreign matter can be reliably detected.

  In addition, since at least one of the first line sensor and the second line sensor is configured by a direct conversion type flat panel detector, it is not necessary to provide a scintillator and a photodiode in at least one of the two line sensors. It becomes possible to simplify the structure of the apparatus.

  As described above, since the area of the receiving surface of the second line sensor is an integral multiple of the area of the receiving surface of the first line sensor, image enlargement processing, compression processing, and the like for specifying minute foreign matters are simplified. Is done. Therefore, the process up to the detection of the minute foreign matter can be easily performed, and the minute foreign matter can be reliably detected.

1 is a schematic external view showing an example of an X-ray inspection apparatus according to the present embodiment. It is a schematic diagram which shows the internal structure of a X-ray inspection apparatus. It is a schematic diagram which shows an example of the arrangement | sequence of a 1st photodiode and a 2nd photodiode. It is a schematic diagram which shows the other example of the arrangement | sequence of a 1st photodiode and a 2nd photodiode. It is a schematic diagram which shows the further another example of the arrangement | sequence of a 1st photodiode and a 2nd photodiode. It is a typical external view which shows the other example of a X-ray inspection apparatus. It is a typical external view which shows the structure of the conventional X-ray inspection apparatus. It is a figure for demonstrating the conventional image processing.

  Hereinafter, an X-ray inspection apparatus according to an embodiment of the present invention will be described with reference to the drawings.

  FIG. 1 is a schematic external view showing an example of the X-ray inspection apparatus 100 according to the present embodiment, and FIG. 2 is a schematic external view showing an example of the internal configuration of the X-ray inspection apparatus 100.

As shown in FIGS. 1 and 2, the X-ray inspection apparatus 100 includes an X-ray irradiation apparatus 200, a first line sensor 300, a second line sensor 400, and a belt conveyor 800.
The belt conveyor 800 of FIG. 1 is formed so as to protrude outside the X-ray inspection apparatus 100, and a plurality of X-ray leakage prevention curtains 850 are provided in the vicinity of the protrusion. The operator drives the X-ray inspection apparatus 100 by operating the touch panel screen MT. The X-ray inspection apparatus 100 performs an X-ray inspection as to whether or not there is a minute foreign object BI inside the X-ray inspection apparatus 100 by carrying an inspection object KS such as a product on the belt conveyor 800 and transporting it. It is.

  The belt conveyor 800 is provided to circulate by winding an endless member around a pair of rotating rollers (not shown), and an outward path 801 and a return path 802 are shown in FIG. Between the forward path 801 and the return path 802, the first line sensor 300 and the second line sensor 400 are arranged vertically. The belt conveyor 800 conveys the inspection object KS in the direction of the arrow L1 (hereinafter referred to as the conveyance direction L1) by the forward path 801. At this time, the X-ray S1 is irradiated onto the inspection object KS from the X-ray irradiation apparatus 200 disposed above the belt conveyor 800.

Here, as shown in FIG. 2, the first line sensor 300 includes a first photodiode array 312 including a plurality of first photodiodes 311 and a first scintillator 313 that performs optical conversion. Further, the second line sensor 400 includes a second photodiode array 422 composed of a plurality of second photodiodes 421 and a second scintillator 423 that performs optical conversion.
The first scintillator 313 and the second scintillator 423 include a large number of scintillator elements (not shown). Note that the number and arrangement of the first photodiode 311 and the second photodiode 421 will be described later.

  The first scintillator 313 emits light (converts light) according to the intensity of the received X-ray S1. The plurality of first photodiodes 311 detect light from the first scintillator 313, respectively. Similarly, the second scintillator 423 emits light (converts light) according to the intensity of the received X-ray S1. The plurality of second photodiodes 421 detect light from the second scintillator 423, respectively. Based on these detection results, the minute foreign matter BI in the inspection object KS is detected.

  FIG. 3 is a schematic diagram showing the arrangement of the plurality of first photodiodes 311 and the plurality of second photodiodes 421. FIG. 3A is an external perspective view of the plurality of first photodiodes 311 and the plurality of second photodiodes 421, and FIG. 3B is a plan view of the plurality of first photodiodes 311 and the plurality of second photodiodes 421. Show arrows.

  As shown in FIGS. 3A and 3B, the receiving surface that receives the X-ray S <b> 1 of the first line sensor 300 is configured by individual surfaces of the first photodiode 311, and The receiving surface that receives the irradiation of the X-ray S <b> 1 is configured by individual surfaces of the second photodiode 421.

  As shown in FIG. 3A, the plurality of first photodiodes 311 are arranged along a direction (hereinafter referred to as a crossing direction) L2 that intersects the transport direction L1 in the horizontal plane in the transport direction L1. The plurality of second photodiodes 421 are arranged side by side along the intersecting direction L2.

As shown in FIG. 3B, the surface of the first photodiode 311 is formed by a distance L31 and a distance L32, and the surface of the second photodiode 421 is formed by a distance L41 and a distance L42.
In the present embodiment, the surface of each second photodiode 421 has an area that is an integral multiple of the surface of each first photodiode 311. That is, the multiplication result of the distance L41 and the distance L42 is an integral multiple of the multiplication result of the distance L31 and the distance L32.

  Specifically, in FIG. 3B, the plurality of second photodiodes 421 have one side distance L42 in the intersecting direction L2 of each second photodiode 421 equal to one side in the intersecting direction L2 of each first photodiode 311. They are arranged side by side so as to be an integral multiple of the distance L32 (in FIG. 3, a double example is shown). In this case, the size (area) of the surface of each second photodiode 421 is twice the size of the surface of each first photodiode 311.

(Other examples)
Next, an arrangement of a plurality of first photodiodes 311 and a plurality of second photodiodes 421 different from that in FIG. 3 will be described.

  FIG. 4 is a schematic diagram illustrating another example of the arrangement of the plurality of first photodiodes 311 and the plurality of second photodiodes 421. FIG. 4A is an external perspective view of the plurality of first photodiodes 311a and the plurality of second photodiodes 421a, and FIG. 4B is a plan view of the plurality of first photodiodes 311a and the plurality of second photodiodes 421a. Show arrows.

  As shown in FIGS. 4A and 4B, the plurality of first photodiodes 311a are arranged in parallel along the transport direction L1. A plurality of first photodiodes 311a constitute a first photodiode array 312.

  In the second photodiode 421a, the distance L43 on one side in the transport direction L1 of the second photodiode 421a is an integral multiple of the distance L33 on one side in the transport direction L1 of each first photodiode 311a (in FIG. 4, double the distance L33). An example is shown). In this case, the size (area) of the surface of the second photodiode 421a is twice the size of the surface of each first photodiode 311a.

(Still other examples)
FIG. 5 is a schematic diagram showing still another example of the arrangement of the plurality of first photodiodes 311 and the plurality of second photodiodes 421. 5A shows an external perspective view of the plurality of first photodiodes 311b and the plurality of second photodiodes 421b, and FIG. 5B is a plan view of the plurality of first photodiodes 311b and the plurality of second photodiodes 421b. Show arrows.

  As shown in FIGS. 5A and 5B, the plurality of first photodiodes 311b are arranged side by side along the intersecting direction L2 and arranged to form a row in the transport direction L1. Is done. A plurality of first photodiodes 311b constitute a first photodiode array 312. A plurality of second photodiodes 421b constitute a second photodiode array 422.

  In the plurality of second photodiodes 421b, the distance L46 on one side in the intersecting direction L2 of each second photodiode 421b is an integral multiple of the distance L36 on one side in the intersecting direction L2 of each first photodiode 311b (2 in FIG. 5). The distance L45 of one side in the transport direction L1 of the second photodiode 421b is an integral multiple of the distance L35 of one side in the transport direction L1 of each first photodiode 311b (in FIG. 5, They are arranged side by side so that a double example is shown. In this case, the size (area) of the surface of each second photodiode 421b is four times the size of the surface of each first photodiode 311b.

  As described above, in the X-ray inspection apparatus 100 according to the present embodiment, the size of the object on each output image in the processing of the output image obtained by the first line sensor 300 and the second line sensor 400. Even when the two are aligned with each other, the area of the receiving surface of the second line sensor 400 (distance L41 × distance L42, distance L43 × distance L44, or distance L45 × distance L46) is the area of the receiving surface of the first line sensor 300 (distance Since L31 × distance L32, distance L33 × distance L34, or distance L35 × distance L36), the image enlargement process and the compression process for specifying the minute foreign object BI are simplified. Therefore, the processing up to the detection of the minute foreign object BI can be easily performed, and the minute foreign object BI can be reliably detected.

  Therefore, according to the X-ray inspection apparatus 100 according to the present embodiment, processing up to the detection of the minute foreign object BI can be easily performed, and the detection of the minute foreign object BI can be reliably performed. .

  In this embodiment, the receiving surface is a surface (distance L41 × distance L42, distance L43 × distance L44, or distance L45 × distance L46, distance L31 × distance L32, distance L33 × distance L34, or distance L35 × distance. L36), the inspection object KS corresponds to the object, and the minute foreign object BI corresponds to the foreign object.

(Other examples)
The X-ray inspection apparatus 100 may be configured as follows. FIG. 6 is a schematic external view showing another example of the X-ray inspection apparatus 100.

  As shown in FIG. 6, in the X-ray inspection apparatus 101, an example in which both the first line sensor 300 and the second line sensor 400 are configured by direct conversion type flat panel detectors 500 and 600 is shown.

  As described above, by employing the direct conversion type flat panel detectors 500 and 600, the scintillator and the photodiode need not be provided in at least one of the first line sensor 300 and the second line sensor 400. The structure of 101 can be simplified.

  In the present embodiment, the area of the receiving surface of the second line sensor 400 has been described as being an integral multiple of the area of the receiving surface of the first line sensor 300, specifically two times and four times. It is not limited to 3 times, 5 times, 6 times, 7 times, 10 times, 20 times, and any other integer times. Further, at least one of the first line sensor 300 and the second line sensor 400 of FIG. 1 may be configured by a direct conversion type flat panel detector capable of directly converting image data from the X-ray S1. For example, the first line sensor 300 and the direct conversion flat panel detector 600 or the second line sensor 400 and the direct conversion flat panel detector 500 may be used.

  A preferred embodiment of the present invention is as described above, but the present invention is not limited thereto. It will be understood that various other embodiments may be made without departing from the spirit and scope of the invention. Furthermore, in this embodiment, although the effect | action and effect by the structure of this invention are described, these effect | actions and effects are examples and do not limit this invention.

100, 101 X-ray inspection apparatus 200 X-ray irradiation apparatus 300, 400 Line sensor 311, 421 Photodiode 312, 422 Photodiode array 313, 423 Scintillator 500, 600 Direct conversion type flat panel detector 800 Belt conveyor BI Small foreign matter KS Inspection object L1 Transport direction L2 Crossing direction S1 X-ray

Claims (4)

An X-ray inspection apparatus for transporting an object and detecting foreign matter in the object,
An X-ray irradiation apparatus for irradiating the object with X-rays;
A first line sensor and a second line sensor that receive the X-rays irradiated from the X-ray irradiation device,
The first line sensor is disposed vertically above the second line sensor,
An X-ray inspection apparatus, wherein the receiving surface of the second line sensor that receives X-ray irradiation has an area that is an integral multiple of the receiving surface of the first line sensor that receives X-ray irradiation. The first line sensor includes a scintillator that performs light conversion and a plurality of first photodiodes,
The second line sensor includes a scintillator that performs light conversion and a plurality of second photodiodes,
The receiving surface of the first line sensor is configured by the surfaces of the plurality of first photodiodes,
The receiving surface of the second line sensor is configured by the surfaces of the plurality of second photodiodes,
2. The X-ray inspection apparatus according to claim 1, wherein the surface of each second photodiode has an area that is an integral multiple of the surface of each first photodiode.   The length of one side of each of the second photodiodes in the conveyance direction of the object is an integral multiple of the length of one side of each of the first photodiodes in the conveyance direction of the object. The X-ray inspection apparatus according to claim 2.   The length of one side in the intersecting direction intersecting the transport direction in the horizontal plane in the transport direction of the target object of the target object of each second photodiode is in the intersecting direction of each first photodiode. 4. The X-ray inspection apparatus according to claim 2, wherein the X-ray inspection apparatus is an integral multiple of the length of one side.