JP2016106794A - Radiation imaging system - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a radiation imaging system capable of suppressing a possible artifact to occur in long length radiography.SOLUTION: A radiation imaging system includes multiple radiation imaging units disposed so as to overlap each other partially and spatially in view from an irradiation source, the radiation imaging unit having a radiation detection panel 2 and a housing involving the radiation detection panel 2. The radiation imaging system obtains a radiographic image on the basis of image signals from the multiple radiation imaging units. The housing 1 of at least one radiation imaging unit D1 of the multiple radiation imaging units has a thinner thickness at a part of a region spatially overlapping other radiation imaging unit D2 than the other part of the region.SELECTED DRAWING: Figure 3

Description

  The present invention relates to a radiation imaging system applied to a medical diagnostic imaging apparatus, a nondestructive inspection apparatus, an analysis apparatus using radiation, and the like.

  In recent years, for example, in the medical field, there is a demand for imaging with a long observation area (hereinafter referred to as long imaging), such as imaging the entire spinal cord or lower limbs or the entire body in order to grasp the distortion or abnormality of the subject's body. In particular, a radiation imaging system that can perform long imaging with a single radiation exposure is compared to a radiation imaging system that performs long imaging by dividing the observation region into a plurality of sections and performing radiation irradiation multiple times. It is more desirable from the viewpoint of elimination and exposure reduction.

  Patent Document 1 discloses a radiation imaging system in which a plurality of radiation imaging apparatuses are photographed side by side so that long imaging can be performed with no image missing even at a single radiation exposure. In Patent Document 1, when the second radiation imaging apparatus and the first radiation imaging apparatus arranged on the radiation irradiation side overlap with each other when viewed from the radiation irradiation direction, the control of the first radiation imaging apparatus is performed. The substrates are respectively arranged so as not to overlap the pixel array of the second radiation imaging apparatus. Image information is obtained from the radiation applied to the overlapping portion by the pixel array of the first radiation imaging apparatus. By synthesizing images from both radiation imaging apparatuses, a long image with no image omission at the joint can be obtained.

JP2012-040140A

  However, in the configuration of Patent Document 1, there is no mention of the influence on the image by the housing of each radiation imaging device, and the housing of the first radiation imaging device adds an artifact to the image obtained from the second radiation imaging device. There is a risk of generating. Therefore, an object of the present invention is to provide a technique that is advantageous for suppressing artifacts that may occur in an image obtained from the second radiation imaging apparatus due to the housing of the first radiation imaging apparatus. .

  The radiation imaging system of the present invention includes a radiation detection panel that has a plurality of pixels arranged in a two-dimensional matrix, and converts irradiated radiation into an image signal, and a housing that includes the radiation detection panel A plurality of radiation imaging devices having a plurality of radiation imaging devices arranged so that each of them is spatially overlapped when viewed from the radiation irradiation side, and radiographic images are obtained based on the respective image signals from the plurality of radiation imaging devices. In the radiation imaging system to be acquired, the housing of at least one radiation imaging apparatus among the plurality of radiation imaging apparatuses has a region in which the outer thickness of the region is different from the region corresponding to the part It is characterized by being thinner than the thickness of the outer shape.

  According to the present invention, it is possible to suppress artifacts that may occur in an image obtained from the second radiation imaging apparatus due to the housing of the first radiation imaging apparatus.

Schematic sectional view for explaining a radiation imaging system Schematic sectional view for explaining a radiation imaging system 1 is a schematic cross-sectional view of a radiation imaging apparatus according to a first embodiment. 1 is a schematic cross-sectional view of a radiation imaging apparatus according to a first embodiment. 1 is a schematic cross-sectional view of a radiation imaging apparatus according to a first embodiment. 1 is a schematic cross-sectional view of a radiation imaging apparatus according to a first embodiment. Sectional schematic diagram and plane schematic diagram of a radiation imaging apparatus according to the second embodiment Plane schematic diagram of a radiation imaging apparatus according to the second embodiment

  Hereinafter, embodiments of the present invention will be specifically described with reference to the accompanying drawings. However, details of dimensions and structures shown in each embodiment are not limited to those shown in the text and the drawings. In this specification, not only X-rays but also α rays, β rays, γ rays, particle rays, cosmic rays, and the like are included in the radiation.

  First, a radiation imaging system according to the present invention will be described with reference to FIGS. 1 (a), 1 (b), 2 (a), and 2 (b). FIG. 1A, FIG. 1B, FIG. 2A, and FIG. 2B are schematic cross-sectional views for explaining examples of radiation imaging systems.

  The radiation imaging apparatus set S in the radiation imaging system in each of the above drawings includes a first radiation imaging apparatus D1, a second radiation imaging apparatus D2, and a third radiation imaging apparatus D3. The first radiation imaging apparatus D1 is arranged on the radiation generating apparatus R side, that is, the radiation irradiation side, relative to the second radiation imaging apparatus D2. Further, the first radiation imaging apparatus D1 is arranged so that a part thereof spatially overlaps with a part of the second radiation imaging apparatus D2 when viewed from the radiation irradiation side. Here, spatially overlapping may be physically contacting and overlapping, or may be overlapping via space without physically contacting. In the example shown in FIG. 1A, the third radiation imaging apparatus D3 is disposed on the opposite side of the radiation generation apparatus R from the first radiation imaging apparatus D1, that is, on the opposite side to the radiation irradiation side. ing. The first radiation imaging apparatus D1 is arranged so that a part thereof spatially overlaps with a part of the third radiation imaging apparatus D3 when viewed from the radiation irradiation side. On the other hand, in the example shown in FIG. 1B, the third radiation imaging apparatus D3 is arranged on the radiation generating apparatus R side, that is, the radiation irradiation side, relative to the second radiation imaging apparatus D2. And the 3rd radiation imaging device D3 is arrange | positioned so that the one part may overlap with a part of 2nd radiation imaging device D2 seeing from the radiation irradiation side. In the configurations of FIGS. 1A and 1B, the thickness of the entire radiation imaging apparatus set S is suppressed. In particular, in the configuration shown in FIG. 1B, only the second radiation imaging apparatus D2 includes other radiation imaging apparatuses that partially overlap on the radiation irradiation side, and this affects the spatial overlap. The number of radiation imaging devices to be received can be reduced. In the example shown in FIGS. 2A and 2B, the third radiation imaging apparatus D3 is on the opposite side of the radiation generating apparatus R from the second radiation imaging apparatus D2, that is, on the radiation irradiation side. Are arranged on the opposite side. The second radiation imaging apparatus D2 is arranged so that a part thereof spatially overlaps with a part of the third radiation imaging apparatus D3 when viewed from the radiation irradiation side. The subject M is positioned with respect to the radiation imaging apparatus set S and the radiation generation apparatus R by standing on a platform placed in front of the radiation imaging apparatus set S. The radiation X emitted from the radiation generator R toward the radiation imaging apparatus set passes through the subject M, reaches the radiation imaging apparatuses D1 to D3, and is captured by being converted into an image signal. Image signals obtained by the radiation imaging apparatuses D1 to D3 are combined by an image processing apparatus (not shown), and a radiation image of the subject M is acquired. 2A and 2B, the radiation imaging apparatuses D1 to D3 are inclined with respect to the casing of the radiation imaging apparatus set S in order to suppress the thickness of the casing of the radiation imaging apparatus set S. However, the present invention is not limited to this.

(First embodiment)
Next, a first embodiment of the present invention will be described with reference to FIGS. 3 (a) and 3 (b). FIG. 3A is a schematic cross-sectional view showing an example according to the first embodiment, in which a round frame portion of FIG. 1A is enlarged, and FIG. 3B is a cross-sectional view of FIG. It is a cross-sectional schematic diagram which shows the other example which concerns on 1st Embodiment which expanded the round frame part.

  As shown in FIG. 2 (a), the plurality of radiation imaging devices D1 and D2 respectively include an integrated circuit IC mounted on the radiation detection panel 2, the flexible circuit board 8 and / or the printed circuit board 5, and the housing 1. including. The radiation detection panel 2 has a pixel array including a plurality of pixels arranged in a two-dimensional matrix, and converts the irradiated radiation into an image signal. The integrated circuit IC mounted on the flexible circuit board 8 and / or the printed circuit board 5 is electrically connected to the radiation detection panel 2. The housing 1 contains at least the radiation detection panel 2 and the integrated circuit IC.

  The housing of at least one radiation imaging device among the plurality of radiation imaging devices of such a radiation imaging set S has a radiation transmittance in a region corresponding to a part of the radiation imaging device that is spatially overlapped with another radiation imaging device. The radiation transmittance of a region different from that region is higher. More specifically, the casing of the first radiation imaging apparatus D1 disposed on the radiation irradiation side of the second radiation imaging apparatus D2 among the plurality of radiation imaging apparatuses of the radiation imaging set S has the following configuration. Is provided. The housing has a second region in which the radiation transmittance of the first region spatially overlapping the second radiation imaging apparatus D2 when viewed from the radiation irradiation side faces the integrated circuit IC of the first radiation imaging apparatus D1. The thickness of the first region is made thinner than the maximum thickness of the region other than the first region so as to be higher than the region radiation transmittance. More specifically, the outer thickness of the first region is made thinner than the outer thickness of the second region. With such a configuration, radiation absorption in the housing of the first radiation imaging apparatus D1 that spatially overlaps the second radiation imaging apparatus D2 is suppressed. This suppresses a decrease in the signal obtained from the pixels spatially overlapping the first region among the image signals obtained by the second radiation imaging apparatus D2, and is attributed to the casing of the first radiation imaging apparatus. Thus, artifacts that can occur in an image obtained from the second radiation imaging apparatus are suppressed.

  A specific example of each radiation imaging apparatus according to the first embodiment will be described below. In each of the radiation imaging apparatuses D1 to D3, a combined body in which the radiation detection panel 2, the adhesive material 3, the base 4, and the printed circuit board 5 are stacked in this order from the radiation irradiation side is included in the housing 1. The radiation detection panel 2 is supported by the base 4 by the radiation detection panel 2 being coupled to the base 4 by the adhesive material 3. The printed circuit board 5 is disposed on the opposite side of the radiation detection panel 2 with the base 4 interposed therebetween.

  The casing 1 has a maximum outer thickness of the first region of the first radiation imaging device D1 that spatially overlaps the second radiation imaging device D2 when viewed from the radiation irradiation side in a region other than the first region. It is thinner than the thickness of the outer shape. More specifically, the thickness of the first region is made thinner than the thickness of the outer shape of the second region facing the integrated circuit IC of the first radiation imaging apparatus D1. In particular, the thickness of the outer shape of the housing of the first radiation imaging apparatus D1 in the first region is preferably configured to become thinner toward the end portion in the first region. In the example shown in FIG. 3A, in the first region of the first radiation imaging apparatus D <b> 1, chamfering is performed on the ridge line portion that connects the radiation-irradiation-side surface and the side surface of the housing 1. An inclined region inclined from a direction parallel to the side surface of the (Slanted Area). Thereby, the thickness of the outer shape of the housing 1 in the first region is thinner than the thickness of the outer shape of the housing 1 in the second region and the third region (Effective Area) facing the pixel array. . Moreover, by having the inclined region, the height of the side surface in the first region of the housing 1 is lower than the height of the side surface when the inclined region is not provided, and the radiation transmittance is increased. Further, as shown in FIG. 3 (b), when the inclined region is made wider than in FIG. 3 (a), the height of the side surface in the first region of the housing 1 becomes lower, and the radiation transmittance is higher. Furthermore, the width of the first region becomes wider. Further, the inclined region may be provided not only on the side portion including the first region among the side portions viewed from the radiation irradiation side of the housing 1 but also on other side portions not including the first region. Good. The radiation detection panel 2 has a pixel array capable of capturing radiation and a peripheral edge on the outer periphery of the pixel array. The second radiation imaging apparatus D2 is arranged so that the pixel array partially overlaps the pixel array of the first radiation imaging apparatus D1, and any one of the radiation imaging apparatuses D1 and D2 is arranged in any line. The image information is surely acquired. The combined radiation image includes an image signal of the first radiation imaging apparatus D1 and an image signal of an area not obtained by the first radiation imaging apparatus D1 among the image signals of the second radiation imaging apparatus D2. Created by synthesis. Here, in the area from the pixel array end of the first radiation imaging apparatus D1 to the end of the housing, the structure of the first radiation imaging apparatus D1 is reflected in the second radiation imaging apparatus D2, and is combined. Artifacts may occur in radiographic images. Therefore, in the present embodiment, the outer thickness of the first region of the first radiation imaging apparatus D1 that spatially overlaps the second radiation imaging apparatus D2 when viewed from the radiation irradiation side is other than the first region. It is thinner than the maximum thickness of the outer shape of the region. Thereby, compared with the case where the thickness of the external shape of the said part is the same as the thickness of another external shape, attenuation | damping of the radiation by the radiation absorption by the housing in the said area | region can be suppressed. If there is little reduction in the output of the radiation image, for example, by combining with the information on the output reduction amount of the radiation image acquired in advance, the image in the region can be corrected to improve the image quality.

  Further, as shown in FIGS. 4A to 4C, in the first region of the first radiation imaging apparatus D1, a ridge line connecting the surface and the side surface of the housing 1 opposite to the radiation irradiation side. The part may be chamfered, and the side surface of the housing 1 may have an inclined region inclined. Further, as shown in FIG. 4 (b), when the inclined region is made wider than in FIG. 4 (a), the height of the side surface in the first region of the housing 1 becomes lower, and the radiation transmittance is higher. Furthermore, the width of the first region becomes wider. Further, as shown in FIG. 4C, the inclined region may be a curved surface instead of a flat surface, or a combination of a curved surface and a flat surface. This can also be applied to the configuration shown in FIGS. 3A and 3B in which an inclined region is provided on the radiation irradiation side.

  In addition, as shown in FIGS. 5A to 5C, in the first region of the first radiation imaging apparatus D1, the inclined region is a base of the first radiation imaging apparatus D1 when viewed from the radiation irradiation side. 4 may be provided up to a region that spatially overlaps a part of 4. In such a case, as shown in FIG. 5A, it is desirable that the side surface of the base 4 is inclined in accordance with the inclined region. Moreover, as shown in FIG.5 (b), in the 1st area | region of 1st radiation imaging device D1, the whole side surface of the housing | casing 1 may be made into the inclination area | region. Further, as shown in FIG. 5C, in the first region of the first radiation imaging apparatus D1, the entire side surface of the housing 1 may be a curved inclined region.

  Moreover, as shown in FIG. 6, the ridgeline part which connects the surface and side surface of the housing 1 on the radiation irradiation side is chamfered to have an inclined region, and the side opposite to the radiation irradiation side of the housing 1 Chamfering may be applied to the ridge line portion connecting the front surface and the side surface of the surface to have an inclined region. Such a configuration is preferably applied to the radiation imaging apparatus used in the radiation imaging apparatus set S shown in FIGS. 2 (a) and 2 (b).

(Second Embodiment)
Next, the second embodiment will be described with reference to FIGS. 7A and 7B. FIG. 7A is a schematic cross-sectional view in which the round frame portion of FIG. 1 is enlarged, and FIG. 7B is a schematic plan view of the first radiation imaging apparatus D1 according to the second embodiment. In addition, the same code | symbol is provided to the same structure as 1st Embodiment, and detailed description is abbreviate | omitted.

  The second embodiment is different from the first embodiment in that it includes the following configuration. The housing 1 has a higher radiation transmittance in the first region spatially overlapping the second radiation imaging apparatus D2 when viewed from the radiation irradiation side than in a region different from the region. The 1st member 13 and the 2nd member 6 are included so that it may become high. With such a configuration, radiation absorption in the housing of the first radiation imaging apparatus D1 that spatially overlaps the second radiation imaging apparatus D2 is suppressed. This suppresses a decrease in the signal obtained from the pixels spatially overlapping the first region among the image signals obtained by the second radiation imaging apparatus D2, and is attributed to the casing of the first radiation imaging apparatus. Thus, artifacts that can occur in an image obtained from the second radiation imaging apparatus are suppressed.

  The first member 13 is a member having a higher radiation transmittance than the second member 6. The first member 13 constituting the first region is preferably made of a material having an aluminum equivalent of 5 mm or less in radiation transmission from the radiation incident direction, and for example, CFRP is used. In addition, in the area | region which opposes a pixel array among the 1st members 13, it is desirable that it is higher than the radiation transmittance in a 1st area | region. On the other hand, the second member 6 constituting the second region is preferably a material having higher rigidity and lower radiation transmittance than the first member 13, and a metal material such as aluminum or magnesium is used. The first member 13 and the second member 6 are coupled to each other using the screw 7 outside the first region, so that the radiation image to which the screw 7 is coupled is not reflected.

  As shown in FIG. 7B, the housing 1 has a substantially square shape, and one of the four sides is constituted by the first member 13, but the remaining three sides and all corners are second. A member 6 is used. With such a configuration, it is possible to ensure the drop strength from the corner and the rigidity of the entire apparatus. Further, when CFRP is used as the first member 13, it is difficult to form a box shape because of poor shapeability. In this respect, it is advantageous to use only one side as CFRP. The housing 1 includes a power switch 10 for the radiation imaging apparatus, a display unit 11 such as an LED for displaying the state of the radiation imaging apparatus, and a connection unit 9 connected to a cable 12 for transmitting and receiving a power supply base signal to the integrated circuit IC. Is provided. In the 1st radiation imaging device D1, these are arrange | positioned in the area | region except the 1st area | region which overlaps with the 2nd radiation imaging device D2. In the present embodiment, by providing the second member 6, the structure does not appear in the combined radiation image. A flexible circuit board 8 electrically connected to the printed circuit board 5 is electrically connected to the radiation detection panel 2 on two sides orthogonal to each other. The flexible circuit board 8 of the first radiation imaging apparatus D1 is arranged in an area excluding the first area that spatially overlaps the second radiation imaging apparatus D2, thereby allowing the flexible circuit board 8 to be combined with the combined radiation image. The structure is such that there is no reflection. In addition, as described above, the region other than the first region in the housing is preferably visible from the outside in order to prevent an error in the orientation during installation.

  In addition, as shown in FIG. 8, among the four sides of the substantially rectangular casing, three sides including the first region are composed of the first member 13, and the remaining one side is composed of the second member 6. May be. In that case, a flexible circuit board 8 (not shown), a power switch 10, a display unit 11, and a connection unit 9 are provided on one side of a casing made of the second member 6. With such a configuration, when the housing 1 has a substantially rectangular shape when viewed from the radiation irradiation side, both the short side and the long side are configured by the first member 13. In this configuration, when it is desired to obtain a radiation image combined in a more vertically long region, the short side is overlapped as the first region, and when a more horizontally long combined radiation image is desired, a long side is obtained. Can be superimposed as the first region. As a result, the second embodiment has a higher degree of freedom in shooting than the first embodiment.

M subject R radiation generator S radiation imaging device set D1 first radiation imaging device D2 second radiation imaging device D3 third radiation imaging device 1 housing 2 radiation detection panel 5 printed circuit board 8 flexible circuit board

Claims (12)

A plurality of radiation imaging apparatuses, each having a radiation detection panel that converts radiation irradiated with a plurality of pixels arranged in a two-dimensional matrix into an image signal, and a housing that contains the radiation detection panel, In a radiation imaging system that arranges each part so as to overlap spatially when viewed from the radiation irradiation side and acquires a radiation image based on each image signal from the plurality of radiation imaging devices,
The housing of at least one radiation imaging device of the plurality of radiation imaging devices has an outer thickness of the region in the part being thinner than an outer thickness of the region different from the region in the part. A radiation imaging system. Each of the plurality of radiation imaging devices further includes an integrated circuit electrically connected to the radiation detection panel;
The housing further includes the integrated circuit,
The housing of the first radiation imaging apparatus disposed on the radiation irradiation side of the second radiation imaging apparatus among the plurality of radiation imaging apparatuses is connected to the second radiation imaging apparatus as viewed from the radiation irradiation side. The outer thickness of the first region that spatially overlaps is thinner than the outer thickness of the second region facing the integrated circuit of the first radiation imaging apparatus. The radiation imaging system described.   3. The radiation imaging system according to claim 2, wherein the thickness of the outer shape of the casing of the first radiation imaging apparatus in the first region becomes thinner toward an end portion in the first region. .   The housing of the first radiation imaging apparatus includes: a first member constituting the first region; and a second member having a rigidity higher than that of the first member 1 and having a low radiation transmittance. 3. The radiation imaging system according to 3.   The housing of the first radiation imaging apparatus is configured to be substantially rectangular as viewed from the radiation irradiation side, and at least one side of the four sides of the substantially rectangular shape is configured by the first member. The radiation imaging system according to claim 4, wherein the remaining sides excluding the at least one side are configured by the second member.   The radiation imaging system according to claim 5, wherein the first radiation imaging apparatus further includes a power switch, and the power switch is provided on the second member.   The said 1st radiation imaging device further has a display part which displays the state of the said 1st radiation imaging device, The said display part is provided in the said 2nd member, The said 2nd member is characterized by the above-mentioned. Radiation imaging system.   The first radiation imaging apparatus further includes a connection portion connected to a cable for performing power supply and / or signal transmission / reception to the integrated circuit, and the connection portion is provided in the second member. The radiation imaging system according to claim 5, wherein:   9. The radiation imaging system according to claim 5, wherein the first member is made of a material having a radiolucency of an aluminum equivalent of 5 mm or less.   Each of the plurality of radiation imaging apparatuses includes a flexible circuit board electrically connected to the radiation detection panel, a printed circuit board electrically connected to the flexible circuit board, and a base supporting the radiation detection panel The printed circuit board is disposed on the opposite side of the radiation detection panel with the base interposed therebetween, and the integrated circuit is mounted on the printed circuit board and / or the flexible circuit board. The radiation imaging system according to any one of claims 2 to 9.   The housing of the first radiation imaging apparatus has an inclined region inclined in a direction parallel to a side surface of the housing of the first radiation imaging apparatus in the first region. Item 11. The radiation imaging system according to any one of Items 2 to 10.   The radiation imaging system according to claim 11, wherein the inclined region includes a curved surface.

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