WO2017212789A1

WO2017212789A1 - Radiation image pickup device and radiation image pickup system

Info

Publication number: WO2017212789A1
Application number: PCT/JP2017/015451
Authority: WO
Inventors: 慶人佐々木; 尚志郎猿田; 小林　玉樹; 陽平石田
Original assignee: キヤノン株式会社
Priority date: 2016-06-07
Filing date: 2017-04-17
Publication date: 2017-12-14
Also published as: JP2017219416A

Abstract

Disclosed is a radiation image pickup device wherein a first image pickup panel and a second image pickup panel, and an adjustment unit for adjusting the relative positions of the first image pickup panel and the second image pickup panel are disposed in a housing, said first image pickup panel and second image pickup panel being disposed such that respective image pickup surfaces for detecting radiation overlap each other. The adjustment unit includes: a panel supporting unit that supports the first image pickup panel or the second image pickup panel; and an aligning unit for determining the relative positions of the first image pickup panel and the second image pickup panel by moving the panel supporting unit.

Description

Radiation imaging apparatus and radiation imaging system

The present invention relates to a radiation imaging apparatus and a radiation imaging system.

Radiation imaging devices are widely used for medical image diagnosis and nondestructive inspection. A method of acquiring a plurality of radiation images of radiation having different energy components with respect to a subject using the radiation imaging apparatus and acquiring an energy subtraction image in which a specific subject portion is separated or emphasized from a difference between the acquired radiation images. Are known. In Patent Documents 1 to 3, in order to obtain energy subtraction images, two imaging panels are used, and radiation images of radiation of two different energy components are obtained by one radiation irradiation (one-shot method) on a subject. A radiation imaging apparatus for recording the above has been proposed. Patent Document 2 discloses that two imaging panels are detachably fixed to a support substrate. Patent Document 3 shows that a connecting member is used and a position defining portion is provided on one of the imaging panels so that the two imaging panels maintain a predetermined positional relationship.

JP-A-5-208000 JP 2010-101805 A Japanese Patent Laid-Open No. 3-135996

When the two imaging panels are overlapped, even when the method of Patent Document 3 is used, there is a possibility that a positional deviation occurs between the two imaging panels due to the overlay accuracy, the tolerance between the imaging panels, and the like. In addition, when the imaging panel is replaced due to a failure or when an impact is applied to the radiation imaging apparatus, there is a possibility that a positional deviation between the imaging panels occurs. When a positional shift occurs between the imaging panels, the image quality of the energy subtraction image generated from the difference between the radiographic images obtained by the two imaging panels may be deteriorated.

An object of the present invention is to provide an advantageous technique for acquiring an energy subtraction image with a single irradiation of radiation using a plurality of imaging panels in a radiation imaging apparatus.

In view of the above problems, a radiation imaging apparatus according to an embodiment of the present invention includes a first imaging panel, a first imaging panel, and a first imaging panel arranged such that imaging surfaces for detecting radiation overlap each other. And an adjustment unit for adjusting the relative position between the first imaging panel and the second imaging panel, the radiation imaging apparatus arranged in the housing, wherein the adjustment unit includes the first imaging panel and the second imaging panel. A panel support section that supports one of the imaging panels, and a positioning section that moves the panel support section and determines a relative position between the first imaging panel and the second imaging panel. And

The above means provides an advantageous technique for acquiring an energy subtraction image with a single radiation irradiation using a plurality of imaging panels in the radiation imaging apparatus.

Other features and advantages of the present invention will become apparent from the following description with reference to the accompanying drawings. In the accompanying drawings, the same or similar components are denoted by the same reference numerals.

The accompanying drawings are included in the specification, constitute a part thereof, show an embodiment of the present invention, and are used to explain the principle of the present invention together with the description.
, , The top view which shows the structural example of the radiation imaging device which concerns on embodiment of this invention. , , , , , FIG. 1B is a cross-sectional view of the radiation imaging apparatus of FIG. 1A. , FIG. 1B is a cross-sectional view of the radiation imaging apparatus of FIG. 1A. , , , FIG. 1B is a cross-sectional view of the radiation detection apparatus of FIG. 1A. , FIG. 1B is a cross-sectional view of the radiation imaging apparatus of FIG. 1A. The figure explaining the structural example of the radiation imaging system using the radiation detection apparatus which concerns on embodiment of this invention.

Hereinafter, specific embodiments and examples of the radiation imaging apparatus according to the present invention will be described with reference to the accompanying drawings. The radiation in the present invention includes a beam having energy of the same degree or more, such as X-rays, β-rays, γ-rays, etc., which are beams formed by particles (including photons) emitted by radiation decay, such as X It can also include rays, particle rays, and cosmic rays.

The structure of the radiation imaging apparatus according to the embodiment of the present invention will be described with reference to FIGS. 1A to 5B. FIG. 1A is a plan view of a radiation imaging apparatus 100 according to an embodiment of the present invention, and FIGS. 2A to 2C are cross-sectional views taken along a dotted line A-A ′ in FIG. 1A. As shown in FIGS. 2A to 2C, the radiation imaging apparatus 100 is provided with two

imaging panels

101 and 103 each having an imaging surface for detecting radiation in a housing 107. The radiation imaging apparatus 100 includes two

imaging panels

101 and 103 so that an energy subtraction image can be acquired by one-time radiation irradiation (one-shot method) on a subject. For this reason, in the orthogonal projection with respect to the panel 109 provided with the incident surface irradiated with the radiation 110 of the housing | casing 107, the two

imaging panels

101 and 103 are distribute | arranged so that an imaging surface may mutually overlap.

The

imaging panels

101 and 103 each include a detection unit 113 having an imaging surface 111 on which a plurality of pixels for outputting a signal corresponding to incident radiation 110 is arranged. As shown in FIG. 2E, the

imaging panels

101 and 103 may be direct imaging panels using conversion elements that directly convert incident radiation into electrical signals for each pixel. In this case, a semiconductor material such as cadmium telluride (CdTe) or amorphous selenium (a-Se) can be used for the conversion element.

In addition, as shown in FIG. 2F, the

imaging panels

101 and 103 are indirect imaging using a scintillator 112 that converts radiation into light and a conversion element that converts light converted by the scintillator 112 into an electrical signal. A panel may be sufficient. In the configuration illustrated in FIG. 2F, in the

imaging panels

101 and 103, the detection elements of the respective pixels arranged on the imaging surface 111 detect light converted from radiation by the scintillator 112. In this case, for example, a conversion element such as a pn, pin, or MIS type formed using a semiconductor material such as silicon (Si) or germanium (Ge) on a substrate such as glass or plastic, and a thin film transistor (TFT) or the like. And a plurality of pixels including a switch element.

The imaging panel 101 and the imaging panel 103 may be imaging panels having the same configuration or may be imaging panels having different configurations. For example, one of the

imaging panels

101 and 103 may be a direct imaging panel and the other may be an indirect imaging panel. For example, when the

imaging panels

101 and 103 are indirect imaging panels, the scintillator 112 may be the same between the imaging panel 101 and the imaging panel 103 or may be different. The scintillator 112 may be formed directly on the imaging surface 111 by using a vapor deposition method, a printing method, or the like, or the scintillator 112 formed in advance on the base is captured by the imaging surface 111 via a coupling portion such as an adhesive. And may be pasted together.

Also, an adjustment unit for adjusting the relative position between the two imaging panels is arranged in the casing 107. The adjustment unit includes a panel support unit 105 that supports one of the two imaging panels, and a positioning unit 108 (described later) for moving the panel support unit 105 and determining a relative position between the two imaging panels. . In this specification, an imaging panel supported by the panel support unit 105 is referred to as an imaging panel 101, and an imaging panel attached to the housing 107 without the panel support unit 105 interposed therebetween is referred to as an imaging panel 103. Specifically, as shown in FIGS. 2A to 2C, the imaging panel 101 is supported by the panel support unit 105 through the coupling unit 104, and the panel support unit 105 is attached to the housing 107 through the coupling unit 106. It is done. In addition, the imaging panel 103 is attached to the housing 107 via the coupling unit 102. The

coupling portions

102, 104, and 106 may be organic adhesives or adhesive films. Further, by using screws or screws for the

coupling portions

102, 104, 106, between the imaging panel 101 and the housing 107, between the imaging panel 103 and the panel support portion 105, and between the panel support portion 105 and the housing 107. You may fix between each.

Next, the positions arranged in the housing 107 of the

imaging panels

101 and 103 will be described. First, the configuration shown in FIGS. 2A and 2B will be described. 2A and 2B, the housing 107 includes a panel 109 on the incident surface side where the radiation 110 is irradiated as an exterior, and a panel 114 on the opposite side of the panel 109. Further, a support portion 116 for supporting the imaging panel 101 or the imaging panel 103 is provided between the panel 109 and the panel 114. Panel 109 and panel 114 may be integrally formed of the same material. Further, the support portion 116 may be integrally formed with the same material as the exterior of the housing 107 including the panel 109 and the panel 114, or the exterior of the housing 107 using a bonding portion such as an adhesive or a screw. And may be combined. The shape of the support 116 may be a plate shape as shown in FIGS. 2A and 2B, or may be a frame shape along the exterior, for example, and may have a hole in the center.

2A, the imaging panel 101 may be attached to the panel 114 via the panel support unit 105, and the imaging panel 103 may be attached to the support unit 116. In addition, as illustrated in FIG. 2B, the imaging panel 101 may be attached to the support unit 116 via the panel support unit 105, and the imaging panel 103 may be attached to the panel 114. Although not shown, the imaging panel 101 may be attached to one of the panel 109 and the support part 116 via the panel support part 105, and the imaging panel 103 may be attached to the other of the panel 109 and the support part 116.

Next, the positions arranged in the casing 107 of the

imaging panels

101 and 103 in the configuration shown in FIG. 2C will be described. A housing 107 shown in FIG. 2C includes a panel 109 and a panel 114 constituting an exterior, and does not have a support portion 116 unlike the housing 107 shown in FIGS. 2A and 2B. In the housing 107 that does not include the support unit 116, as illustrated in FIG. 2C, the imaging panel 101 may be attached to the panel 114 via the panel support unit 105, and the imaging panel 103 may be attached to the panel 109. Although not shown, the imaging panel 101 may be attached to the panel 109 via the panel support unit 105, and the imaging panel 103 may be attached to the panel 114.

When a plurality of imaging panels are overlapped in order to obtain a subtraction image by the one-shot method, there is a possibility that a positional deviation occurs between the two imaging panels due to overlay accuracy, tolerance between the imaging panels, and the like. In addition, when the imaging panel is replaced due to a failure or when an impact is applied to the radiation imaging apparatus, there is a possibility that a positional deviation between the imaging panels occurs. When a positional shift occurs between the imaging panels, there is a possibility that the image quality may be deteriorated in the energy subtraction image generated from the difference between the radiographic images obtained by the two imaging panels, for example, the shifted edge portion is emphasized. is there. Therefore, in the present embodiment, the imaging panel 101 is attached to the housing 107 via the panel support unit 105, and the positioning unit 108 moves the panel support unit 105, so that the imaging panel 101 and the imaging panel 103 are relative to each other. Adjust the position. The positional deviation between the imaging panel 101 and the imaging panel 103 is corrected by the adjustment unit configured by the panel support unit 105 and the positioning unit 108.

As shown in FIGS. 1B and 3A, the adjustment unit is configured such that the positioning unit 108 has a screw such as a micrometer head, and moves the panel support unit 105 such as a movable stage as the screw rotates. It may be. With such a configuration, the imaging panel 101 rotates about the axis extending in the direction orthogonal to the imaging surface 111 of the imaging panel 101 in the θ direction, and the relative position between the imaging panel 101 and the imaging panel 103 is adjusted. Is done. Further, the positioning unit 108 may include a driving unit such as an actuator, and for example, an electric screw such as a micrometer head may be operated. For example, as shown in FIG. 1C and FIG. 3B, by using a UVW stage or the like as an adjustment unit, moving the imaging panel 101 in the X-axis and Y-axis directions parallel to the imaging surface 111, the imaging panel 101 and imaging are performed. The relative position with respect to the panel 103 may be adjusted. In this case, the stage part of the UVW stage can function as the panel support part 105, and the actuator that moves the stage part can function as the positioning part 108. The panel support unit 105 can be moved not only in the θ direction but also in the X-axis and Y-axis directions by the positioning unit 108, so that the relative position between the imaging panel 101 and the imaging panel 103 can be adjusted more precisely. At least, the positioning unit 108 may move the panel support unit 105 in the θ direction.

Further, when an actuator is used for the positioning unit 108, the radiation imaging apparatus 100 may further include a storage unit 115 such as a memory that stores an adjustment amount for adjusting the relative position between the imaging panel 101 and the imaging panel 103. Good. For example, when the radiation imaging apparatus 100 is activated, the positioning unit 108 may perform calibration for moving the panel support unit 105 according to the adjustment amount stored in the storage unit 115. The storage unit 115 may be inside the housing 107 as shown in FIG. 1C or outside the housing 107.

As shown in FIGS. 2A to 2C, only one panel support unit 105 (adjustment unit) is not necessarily arranged in the housing 107. As shown in FIG. 2D, the radiation imaging apparatus 100 includes a panel support unit 105 (adjustment unit) for each imaging panel, and the two

imaging panels

101a and 101b arranged in the housing 107 are both panel support units. It may be attached to the housing 107 via 105. In FIG. 2D, the panel support unit 105 is arranged on both imaging panels in the configuration shown in FIG. 2C. However, the panel support unit 105 may be arranged on both imaging panels configured in FIGS. 2A and 2B. . At least one of the imaging panels may be supported by the panel support unit 105 and attached to the housing 107.

The shape of the housing 107 is not limited to the shape shown in FIGS. For example, as illustrated in FIG. 4A, the imaging panel 103 is attached to the casing member 407a, and the imaging panel 101 is attached to the casing member 407b via the panel support unit 105. Further, the housing member 407a and the housing member 407b may be coupled by the coupling unit 401a to form the housing 107 and function as the radiation imaging apparatus 100. As shown in FIG. 4A, the coupling portion 401a may couple the housing member 407a and the housing member 407b using screws, bolts, nuts, or the like, for example, using an adhesive or an adhesive film. Also good. By using the configuration shown in FIG. 4A, when a failure or malfunction occurs in any of the

imaging panels

101 and 103, only the imaging panel in which the malfunction or malfunction occurs can be easily replaced.

For example, in the configuration shown in FIG. 4A, three or more imaging panels may be stacked. In this case, at least one of the stacked imaging panels can be the imaging panel 101 supported by the casing 107 via the panel support unit 105. For example, an imaging panel other than one of the stacked imaging panels may be the imaging panel 101 attached to the housing 107 via the panel support unit 105.

As shown in FIG. 4B, the casing 107 includes a casing member 407c serving as an upper lid constituting the panel 109 on the radiation incident side side, and a lower lid constituting the panel 114 opposite to the incident plane. And a casing member 407d. In the configuration illustrated in FIG. 4B, the imaging panel 103 is supported by the casing member 407c and the imaging panel 101 is supported by the casing member 407d via the panel support unit 105. However, the configuration is not limited thereto. For example, the imaging panel 101 may be attached to the housing member 407c via the panel support portion 105, and the imaging panel 103 may be attached to the housing member 407d without going through the panel support portion 105. As shown in FIG. 4B, the coupling portion 401b may couple the housing member 407c and the housing member 407d using an adhesive, an adhesive film, or the like, or may use a screw or the like, for example.

Here, also in each configuration shown in FIGS. 2A to 2C, the housing 107 may be composed of a plurality of housing members in order to provide an opening for accessing the inside of the housing 107, for example. Also in this case, the respective housing members can be coupled and fixed to each other using an adhesive, an adhesive film, a screw or the like.

The support method of the

imaging panels

101 and 103 is not limited to the above-described configurations. For example, as shown in FIG. 4C, a support base 402a supported by the casing 107 via the coupling portion 403 is arranged in the casing 107, and the

imaging panels

101 and 103 are arranged on the support base 402a. Also good. Further, the support base may not be plate-shaped as shown in FIG. 5A. For example, a frame shape along the outer edges of the

imaging panels

101 and 103 may be used like a support base 402b shown in FIG. 5B. When the

support bases

402a and 402b are used, one of the

imaging panels

101 and 103 is attached to the housing 107 via the

support bases

402a and 402b, and the other is attached to the case without the support bases 402a and 402b. 107 may be attached. By using the configuration shown in FIGS. 4C and 4D, the

imaging panels

101 and 103 can be supported independently from the housing 107, so that the relative position between the imaging panel 101 and the imaging panel 103 can be easily adjusted. Can be.

The positional deviation between the imaging panel 101 and the imaging panel 103 occurs not only before the product shipment of the radiation imaging apparatus 100 but also after the product shipment, for example, when an impact is applied due to the subject colliding with the radiation imaging apparatus 100. sell. For this reason, the adjustment using the adjustment unit including the panel support unit 105 and the positioning unit 108 can be a mechanism that can be adjusted even after product shipment. For example, the radiation imaging apparatus 100 may be irradiated with the radiation 110, and the positional deviation between the imaging panel 101 and the imaging panel 103 may be adjusted according to the radiographic images captured by the imaging panel 101 and the imaging panel 103, respectively. For example, the relative positional deviation between the imaging panel 101 and the imaging panel 103 can be obtained from the radiographic images obtained by the

imaging panels

101 and 103 by arranging and imaging a subject for position adjustment. Good. Further, for example, as shown in FIG. 5A, alignment marks 501 are provided on the

imaging panels

101 and 103, and relative positions between the imaging panel 101 and the imaging panel 103 are obtained from radiographic images obtained by the

imaging panels

101 and 103. A typical positional deviation may be obtained. For example, a UVW stage is used as the positioning unit 108, and the radiation imaging apparatus 100 is continuously irradiated with the radiation 110. You may adjust.

Further, as shown in FIG. 5B, a radiation absorbing layer 502 for absorbing a part of the radiation transmitted through the imaging panel 101 may be disposed between the imaging panel 101 and the imaging panel 103. In the radiation imaging apparatus 100, the imaging panel 103 close to the incident surface irradiated with the radiation 110 can detect low-energy radiation, and the imaging panel 101 far from the incident surface can detect high-energy radiation. By absorbing low-energy radiation among the radiation transmitted through the imaging panel 103 by the radiation absorption layer 502, the energy resolution of the radiation imaging apparatus 100 can be increased. The radiation absorbing layer 502 may be appropriately selected depending on the type of radiation 110 used, the configuration of the

imaging panels

101 and 103, and the like. The radiation absorbing layer 502 may absorb radiation uniformly in the plane. For the radiation absorbing layer 502, for example, a metal such as copper can be used. Further, for example, in the configuration shown in FIG. 2C, a radiation absorbing layer may be disposed on the panel support unit 105, and for example, in the configuration illustrated in FIG. 4C, a radiation absorbing layer may be disposed on the support base 402a. . In these cases, the panel support part 105 and the support base 402a may be made of, for example, metal and function as a radiation absorbing layer.

Hereinafter, a radiation imaging system 600 in which the radiation imaging apparatus 100 of the present invention is incorporated will be exemplarily described with reference to FIG. The radiation imaging system 600 includes, for example, a radiation imaging apparatus 100, a signal processing unit 603 including an image processor, a display unit 604 including a display, and a radiation source 601 for generating radiation. Radiation (for example, X-rays) emitted from the radiation source 601 passes through the subject 602, and radiation including information in the body of the subject 602 is detected by the radiation imaging apparatus 100 of the present embodiment. For example, the signal processing unit 603 performs predetermined signal processing using the radiographic image obtained thereby, and generates image data. This image data is displayed on the display unit 604.

The present invention is not limited to the above embodiment, and various changes and modifications can be made without departing from the spirit and scope of the present invention. Therefore, in order to make the scope of the present invention public, the following claims are attached.

This application claims priority on the basis of Japanese Patent Application No. 2016-113801 filed on June 7, 2016, the entire contents of which are incorporated herein by reference.

Claims

In order to adjust the relative position between the first imaging panel and the second imaging panel, and the first imaging panel and the second imaging panel arranged so that the imaging surfaces for detecting radiation overlap each other. A radiographic imaging device arranged in a housing,
The adjustment unit is
A panel support portion for supporting one of the first imaging panel and the second imaging panel;
A radiation imaging apparatus comprising: a positioning unit configured to move the panel support unit and determine a relative position between the first imaging panel and the second imaging panel.
The housing includes an exterior including a first panel and a second panel, and a support portion disposed between the first panel and the second panel,
The first imaging panel is attached to one of the first panel and the support through the panel support, and the second imaging panel is out of the first panel and the support The radiation imaging apparatus according to claim 1, wherein the radiation imaging apparatus is attached to the other.
The housing includes an exterior including a first panel and a second panel,
The first imaging panel is attached to one of the first panel and the second panel via the panel support, and the second imaging panel is the first panel and the second panel. The radiation imaging apparatus according to claim 1, wherein the radiation imaging apparatus is attached to the other of the panels.
The housing includes a first housing member to which the first imaging panel is attached via the panel support portion, and a second housing member to which the second imaging panel is attached.
The radiation imaging apparatus according to claim 1, wherein the first casing member and the second casing member are coupled to each other by a coupling unit.
The radiation imaging apparatus further includes a support base supported by the casing through a coupling portion in the casing,
The radiation according to claim 1, wherein the first imaging panel is attached to the support base via the panel support portion, and the second imaging panel is attached to the support base. Imaging device.
The radiation imaging apparatus according to any one of claims 2 to 5, wherein the radiation transmitted through the second imaging panel is incident on the first imaging panel.
The radiation imaging apparatus further includes a second adjustment unit for adjusting a relative position between the first imaging panel and the second imaging panel,
The second adjustment unit includes:
A second panel support unit for supporting the second imaging panel;
And a second positioning unit configured to move the second panel support and determine a relative position between the first imaging panel and the second imaging panel. The radiation imaging apparatus according to any one of 2 to 6.
The positioning unit rotates at least the panel support unit about an axis extending in a direction perpendicular to the imaging surface of the imaging panel to be supported among the first imaging panel and the second imaging panel. The radiation imaging apparatus according to claim 1, wherein the radiation imaging apparatus is characterized.
The positioning part has a screw;
The radiation imaging apparatus according to claim 1, wherein the panel support unit is configured to move with the rotation of the screw.
The radiation imaging apparatus according to claim 1, wherein the positioning unit includes an actuator that moves the panel support unit.
The radiation imaging apparatus further includes a storage unit that stores an adjustment amount for adjusting a relative position between the first imaging panel and the second imaging panel;
The radiation imaging apparatus according to claim 10, wherein, when the radiation imaging apparatus is activated, the positioning unit moves the panel support unit according to the adjustment amount stored in the storage unit.
The radiation imaging apparatus according to any one of claims 1 to 11,
A radiation imaging system comprising: a signal processing unit that processes a signal from the radiation imaging apparatus.