X-ray inspection equipment

Abstract

To provide an X-ray inspection device enabling avoidance of such a problem that the magnification thereof reduces due to interference of a sample table with an X-ray source occurring when an analyte is magnified and sawn through.SOLUTION: An X-ray inspection device comprises: a sample table 5 in which an analyte 4 is loaded; a generator 1 that irradiates the analyte 4 with an X-ray; an X-ray detector 3 that is disposed facing the X-ray generator; and an additional table that is detachably fixed to the sample table 5. The additional table may be an extended table that has a large size of an outer periphery of the additional table closer to the generator 1 than the sample table 5. The additional table is a turn table that has a smaller loading surface than the sample table 5, and may be fixed on an outer rim side of the sample table 5.SELECTED DRAWING: Figure 1

Description

Technical Field

[0001] Embodiments of the present invention relate to an X-ray inspection apparatus.

Background Art

[0002] Various types of X-ray inspection apparatuses are known. One of them is known to irradiate a subject 4 with X-rays by placing the subject 4 on a sample table and rotating it. In this type of X-ray inspection apparatus, for example, as shown in Patent Document 1, a sample table is arranged between an X-ray generator having an X-ray source and an X-ray detector, and the subject 4 is irradiated with X-rays from the X-ray source while rotating the sample table, and the transmitted X-rays are detected by the X-ray detector. In this case, in order to be able to inspect subjects 4 of different sizes with the same X-ray inspection apparatus, it is common to make the sample table large according to the largest size of the subject 4.

Prior Art Documents

Patent Documents

[0003]

Patent Document 1

Summary of the Invention

Problems to be Solved by the Invention

[0004] In an X-ray inspection apparatus, when the subject 4 is small, a fluoroscopic image with higher resolution can be obtained by enlarging it as much as possible. Therefore, the subject 4 is often brought as close as possible to the X-ray source. However, if the sample table is large, when photographing a small-sized subject 4 by enlarging it, if one tries to bring it closer to the X-ray source, there is a problem that the subject 4 and the X-ray source interfere with each other and magnification beyond a certain limit cannot be performed. On the other hand, if the sample table is made small from the beginning, when a large subject 4 is mounted, the subject 4 will protrude from the sample table, resulting in poor stability and, in the worst case, a risk of falling.

[0005] Embodiments of the present invention have been made to solve the above problems, and their purpose is to provide an X-ray inspection apparatus that can avoid interference between the sample table and the X-ray source, which reduces the magnification, when magnifying the subject 4. [Means for solving the problem]

[0006] The X-ray inspection apparatus of this embodiment has the following configuration. (1) A sample table on which subject 4 will be placed. (2) An X-ray generator that irradiates subject 4 with X-rays. (3) An X-ray detector positioned opposite the X-ray generator. (4) An additional table that is detachably fixed to the sample table.

[0007] The X-ray inspection apparatus of this embodiment can employ the following configuration. (1) The additional table is an extension table having a larger size than the sample table, with its outer circumference closer to the X-ray generator. (2) The extension table consists of a ring-shaped member that is attached to the outer circumference of the sample table. (3) The additional table is a turntable having a smaller mounting surface than the sample table and is fixed to the outer edge side of the sample table. (4) The additional table is equipped with a sensor that detects when it is mounted on the sample table, Depending on the detection result of the sensor, the distance between the X-ray generator and the sample table, and / or between the X-ray generator and the additional table is limited. [Brief explanation of the drawing]

[0008] [Figure 1] These are a side view and a top view showing the overall configuration of the first embodiment. [Figure 2] These are a cross-sectional view and a plan view showing the sample table portion in the first embodiment. [Figure 3]In the first embodiment, the images show a cross-sectional view and a plan view illustrating the state in which an additional table is attached to the sample table. [Figure 4] These are side and top views showing a large sample table with a small subject 4 mounted on it. [Figure 5] These are side and top views showing a case where a large subject 4 is mounted on a small sample table. [Figure 6] These are a side view and a top view showing the sample table portion in the second embodiment. [Figure 7] In the second embodiment, the following are a cross-sectional view and a plan view showing the state in which the additional table is attached to the sample table. [Modes for carrying out the invention]

[0009] [1. First Embodiment] [1-1. Structure] As shown in Figure 1, the X-ray inspection apparatus of the first embodiment consists of an X-ray generator 1 and a detector 3 that receives the X-ray beam 2 emitted from the focal point F of the generator 1, arranged opposite each other with the subject 4 in between. The X-ray beam 2 is a pyramidal beam centered on the X-ray optical axis. To control the output of the X-ray beam 2, a high-voltage generator 16 is connected to the generator 1, and an X-ray control unit 17 is connected to this high-voltage generator 16. The X-ray control unit 17 controls the anode power of the generator 1 based on the tube current value based on a command from the data processing unit 19 and the tube voltage value set in advance according to the subject 4. The detector 3 detects the X-ray beam 2 that has passed through the subject 4 with two-dimensional spatial resolution and outputs it as transmitted image data to the data processing unit 19 connected to the output side of the detector 3.

[0010] The generator 1 and the detector 3 are supported opposite each other on an X-shift mechanism 8 that moves them in the X direction (the direction of the X-ray optical axis). Specifically, the generator 1 is supported by a support frame 10 provided at one end of the X-shift mechanism 8, and the detector 3 is supported by a support frame 9 provided at the other end.

[0011] The subject 4 is placed on a sample table 5 located between the generator 1 and the detector 3 on the X-shift mechanism 8. The sample table 5 is supported on the X-shift mechanism 8 via a Y-shift mechanism 7 and a rotation / lifting mechanism 6. The Y-shift mechanism 7 moves the sample table 5 and the subject 4 placed on it in the Y direction (direction perpendicular to the X-ray optical axis). The rotation / lifting mechanism 6 rotates the sample table 5 and the subject 4 around the rotation axis 13 on the Y-shift mechanism 7 and also moves them up and down in the vertical direction (Z direction).

[0012] The generator 1, detector 3, rotation / lifting mechanism 6, Y-shift mechanism 7, and X-shift mechanism 8 are connected to the mechanism control unit 18. Based on commands input to the mechanism control unit 18 by the user, the sample table 5, along with the subject 4, is moved along the X-ray optical axis between the generator 1 and the detector 3 by the X-shift mechanism 8, and the imaging distance (distance between focus and rotation axis) FCD is changed. The detector 3 is moved along the X-ray optical axis by the X-shift mechanism 8, and the detection distance (distance between focus and detector) FDD is changed. This changes the imaging magnification FDD / FCD.

[0013] The mechanism control unit 18 controls the amount of lifting and lowering of the rotation / lifting mechanism 6 to move the subject 4 in the Z direction (up or down) in order to perform X-ray imaging with a multi-cone and generate multiple consecutive CT images in the vertical direction (Z direction). After each imaging cycle, the mechanism control unit 18 repeatedly moves the subject 4 in the Z direction by a predetermined amount of lift and lowering, thereby enabling X-ray imaging with a multi-cone. The data processing unit 19 has a scan control unit 22 for controlling the mechanism control unit 18 to perform X-ray imaging, and also includes a reconstruction unit 23 that generates CT images based on transmission image data from the detector 3.

[0014] The mechanism control unit 18 and the data processing unit 19 are configured as part of a computer including a CPU, a memory, a hard disk, an input unit 21 such as a keyboard and a mouse, and a display unit 20 such as a liquid crystal display. On the display unit 20, an input interface of the input unit 21 and a CT image generated based on the transmission image data from the detector 3 are displayed. As the input unit 21, a keyboard, a slide switch, a rotary volume switch, a touch panel, etc. can be used, but in this embodiment, an input interface for operating an image displayed on the liquid crystal display with a pointing device such as a mouse is used.

[0015] In this embodiment, as shown in FIG. 2, the sample table 5 is composed of a disk-shaped member with a small diameter and a small area suitable for placing a relatively small subject 4. An extension table 50 is detachably attached to the outer periphery of the sample table 5 as an additional table. That is, a ring-shaped step portion 5a with the upper edge of the table cut out is provided at the outer peripheral edge of the sample table 5, and this step portion 5a serves as the mounting portion of the extension table 50. As shown in FIG. ️, the extension table 50 is composed of a ring-shaped member with a central opening, and the opening is sized to fit the sample table 5. A step portion 50a that engages with the step portion 5a of the sample table 5 is provided on the inner periphery of the central opening of the extension table 50, and when these step portions 5a and 50a are fitted together, the surfaces of the sample table 5 and the extension table 50 are flush.

[0016] [1-2. Operation] In the first embodiment having the above configuration, when fluoroscoping a small subject 4, the subject 4 is placed on the sample table 5 as shown in FIG. 2. In an X-ray inspection apparatus, it is possible to obtain a higher-resolution image by bringing the subject 4 closer to the generator 1 as much as possible. However, in this embodiment, since the outer diameter of the sample table 5 is small, the limit value A can be reduced, and the subject 4 and the generator 1 can be brought closer.

[0017] When the pixel size of one pixel of the detector 3 is d, the resolution d' on the subject can be obtained by the following calculation formula. d’ = d × FCD / FDD In FIG. 2, since the size of the sample table 5 is slightly larger than the size of the subject 4, when attempting to perform magnified fluoroscopy by reducing FCD, the size of the sample table 5 does not pose much of an obstacle. FIG. 4 shows a case where a small subject 4 is placed on a large sample table 5. In this case, even when attempting to perform magnified fluoroscopy by reducing FCD, due to the large limit value A, the sample table 5 interferes with the generator 1, and unlike in the case of FIG. 2, the subject 4 cannot be brought close to the X-ray tube, resulting in a fluoroscopic image with low resolution.

[0018] On the other hand, as shown in FIG. 5, when a subject 4 larger than the sample table 5 is placed on a small sample table 5, the subject 4 may protrude from the sample table 5, and due to poor stability, there is a risk of it falling at worst. In the present embodiment, in order to prevent this, in the case of a large subject 4, as shown in FIG. 3, by mounting a ring-shaped extension table 50 on the small sample table 5, the subject 4 can be stably placed on the sample table 5 and the extension table 50.

[0019] [1-3. Effects] (1) According to the present embodiment, depending on the size of the subject 4, by using the sample table 5 alone or in combination with the extension table 50, even for a small subject 4, it is possible to bring the generator 1 close to the subject 4, obtain a fluoroscopic image with high resolution, and stably place a large subject 4 on the sample table 5.

[0020] (2) By using the ring-shaped extension table 50, a large-diameter sample table 5 can be obtained with a simple operation of just fitting the extension table 50 into the small sample table 5. Compared with preparing large and small sample tables according to the size of the subject 4 and exchanging them each time, it is easier to change the size.

[0021] (3) By using the stepped sections 5a and 50a to fit the sample table 5 and the extension table 50 together, the surfaces of the sample table 5 and the extension table 50 can be made flush, and the subject 4 can be stably supported.

[0022] [2. Second Embodiment] The second embodiment shown in Figures 6 and 7 is a configuration other than mounting a ring-shaped extension table 50, in which a small additional table is detachably mounted on a large sample table 5. This is suitable for rotational operation for a CT scanner. A turntable 51 equipped with a rotation mechanism 51a is used as the small additional table, and the turntable 51 rotates independently on the stationary sample table 5.

[0023] In the second embodiment, a large subject 4 is typically mounted on a large sample table 5, as shown in Figure 6, for scanning. In the case of a small subject 4, a small turntable 51 is mounted on the large sample table 5 closer to the generator 1, as shown in Figure 7, to enable magnified scanning. In this case, the large sample table 5 is not rotated, and only the small turntable 51 is rotated to acquire CT data.

[0024] In this second embodiment, depending on the size of the subject 4, the sample table 5 can be used alone or in combination with the turntable 51. This makes it possible to bring the generator 1 and the subject 4 close together, even with a small subject 4, allowing for high-resolution fluoroscopic images to be obtained, and enabling the stable placement of large subjects 4 on the sample table 5. In particular, the second embodiment is suitable for X-ray inspection equipment that frequently uses large subjects 4 because it can be used in combination with an existing large sample table 5 and a small turntable 51.

[0025] [3. Other Embodiments] The present invention is not limited to the embodiments described above, and the components can be modified and implemented in practice without departing from the spirit of the invention. Furthermore, various inventions can be formed by appropriately combining the multiple components disclosed in the above embodiments. For example, some components may be deleted from all the components shown in the embodiments. Moreover, components from different embodiments may be appropriately combined. Specifically, the invention also includes the following other embodiments.

[0026] (1) A sensor is provided on or near the sample table 5 to detect whether the extension table 50 is installed. If the extension table 50 is not installed, the mechanism control unit 18 allows the sample table 5 to operate up to a preset limit A, which is the closest point the sample table 5 can get to the generator 1. If the extension table 50 is installed, it is allowed to operate up to a preset limit B. To avoid interference with the detector 3, control similar to that for the interference distance with the generator 1 can also be performed. These controls may be applied to both the generator 1 and the detector 3, or to either one of them.

[0027] (2) As ring-shaped expansion tables 50, several types with different ring widths may be prepared and selected as appropriate according to the size of the subject 4. Alternatively, a larger diameter expansion table 50 may be attached to the outer circumference of the expansion table 50 attached to the outer circumference of the sample table 5.

[0028] (3) Positioning pins or protrusions may be provided on the stepped portions 5a and 50a of the sample table 5 and the extension table 50 to interlock, so that they do not shift when rotated. [Explanation of Symbols]

[0029] 1…Generator 2...X-ray beam 3…Detector 4…Subject 5…Sample Table 6…Rotation and lifting mechanism 7…Y-shift mechanism 8...X-Shift Mechanism 9,10…Support frame 13…Rotation axis 16… High-voltage generator 17…X-ray Control Unit 18... Mechanism Control Unit 19...Data Processing Unit 20…Display section 21...Input section 22...Scan Control Unit 23…Reconstruction section 50... Expansion Table 51... Turntable 51a... Rotation mechanism 5a,50a…Stepped section F…X-ray focus

Claims

1. A sample table on which the subject is placed, An X-ray generator for irradiating the subject with X-rays, An X-ray detector positioned opposite the aforementioned X-ray generator, An additional table that is detachably fixed to the aforementioned sample table, Equipped with, The aforementioned additional table is an extension table having a larger size than the aforementioned sample table, with its outer circumference closer to the X-ray generator. The aforementioned extension table is an X-ray inspection device comprising a ring-shaped member attached to the outer circumference of the sample table.

2. The system includes a sensor that detects when the additional table is mounted on the sample table, The X-ray inspection apparatus according to claim 1, wherein the distance between the X-ray generator and the sample table, and / or between the X-ray generator and the additional table is limited according to the detection result of the sensor.

Images