JP2013096759A - Radiation detection apparatus and radiation image photographing system - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a radiation detection apparatus capable of corresponding to a general-purpose radiation source without using an expensive radiation source, capable of avoiding invalid exposure to a subject by a simple constitution and allowed to be applied to various variations, and to provide a radiation image photographing system including the radiation detection apparatus.SOLUTION: A radiation detection apparatus 18 includes a first imaging part 44A for absorbing at least a part of a soft-ray component out of a radiant ray 16 from the radiation source and detecting at least the radiant ray 16 and a second imaging part 44B for converting the radiant ray 16 radiated from the radiation source and transmitted through a subject 36 into a radiation image and outputting the radiation image.

Description

  The present invention relates to a radiation detection apparatus capable of absorbing a soft line component of radiation that causes ineffective exposure of a subject, and a radiographic imaging system having the radiation detection apparatus.

  2. Description of the Related Art In the medical field, radiation image capturing systems that irradiate a subject with radiation and guide the radiation transmitted through the subject to a radiation detector to capture radiation image information are widely used. As the radiation detector, a conventional radiation film in which the radiation image information is exposed and recorded, or radiation energy as the radiation image information is accumulated in a phosphor, and the radiation image information is obtained by irradiating excitation light. A stimulable phosphor panel that can be extracted as stimulated emission light is known. These radiation detectors supply the radiation film on which the radiation image information is recorded to a developing device to perform development processing, or supply the storage phosphor panel to a reading device to perform reading processing. A visible image can be obtained.

  On the other hand, at the time of surgery, contrast imaging, or treatment of fractures, etc., radiation image information can be read and displayed immediately from the radiation detector after imaging in order to quickly and accurately treat the patient. is necessary. As a radiation detector that can respond to such demands, a solid-state detection element (referred to as a pixel) that converts radiation directly into an electrical signal, or converts radiation into visible light with a scintillator and then converts it into an electrical signal and reads it out. A radiation detector called a flat panel detector (FPD) used has been developed.

  In particular, an X-ray diagnostic imaging device is proposed in which a radiographic image is displayed on a monitor by executing radiography at a set frame rate, so that, for example, the catheter entry status with respect to the subject can be grasped in real time. (For example, refer to Patent Document 1).

  By the way, the radiation source used in such an X-ray diagnostic imaging apparatus or the like is usually wired with a high-voltage cable. However, since this high-voltage cable has a stray capacitance, the tube voltage waveform remains even after high voltage is applied. The tail is long. When the wave tail becomes longer, the soft ray component increases in the X-ray output, and the subject is exposed to the X-ray component that does not contribute to the diagnosis, which causes an invalid exposure.

  Therefore, conventionally, a radiation source has been proposed in which the wave tail of the tube voltage waveform does not occur after the exposure time ends, the switching operation of the inverter stops, and the supply of high-voltage DC output stops. (For example, refer to Patent Document 2).

JP 2011-004966 A JP 11-329784 A

  However, since the technique described in Patent Document 1 incorporates a dedicated circuit in the radiation source so that the wave tail of the tube voltage waveform does not occur, the dedicated circuit described above is applied when applied to a conventional system. In addition to using an expensive radiation source that incorporates, it has become an obstacle to the spread of radiographic imaging systems. In addition, the circuit configuration of the radiation source becomes complicated, and there is a concern of cost increase and failure.

  The present invention has been made in view of such problems, and can be used with a general-purpose radiation source without using an expensive radiation source, and avoids ineffective exposure to a subject with a simple configuration. It is another object of the present invention to provide a radiation detection apparatus and a radiographic imaging system that can be applied to various variations.

[1] A radiation detection apparatus according to a first aspect of the present invention absorbs at least a part of a soft line component of radiation from a radiation source and transmits at least a subject with at least a first imaging unit that detects the radiation. And a second imaging unit that converts the radiation from the radiation source into a radiation image and outputs the radiation image.

[2] In the first aspect of the present invention, the second imaging unit may be more sensitive to a hard line component of the radiation than the first imaging unit.

[3] In this case, the first imaging unit absorbs the soft line component better than the hard line component, and the second imaging unit improves the hard line component of the radiation better than the first imaging unit. You may make it absorb.

[4] In the first aspect of the present invention, the first imaging unit may be installed between the subject and the radiation source at least when shooting the moving image of the subject.

[5] In the first aspect of the present invention, the first imaging unit may be installed between the subject and the second imaging unit at least when photographing the still image of the subject.

[6] In the first aspect of the present invention, the first imaging unit may not be used at least when photographing the still image of the subject.

[7] In the first aspect of the present invention, the first imaging unit may be installed between the subject and the second imaging unit at least during energy subtraction imaging of the subject.

[8] In this case, an energy reduction filter may be installed between the first imaging unit and the second imaging unit.

[9] In the first aspect of the present invention, the first imaging unit may be formed on a rigid first substrate, and the second imaging unit may be formed on a rigid second substrate.

[10] In the first aspect of the present invention, the first imaging unit may be formed on a flexible substrate, and the second imaging unit may be formed on a rigid substrate.

[11] In the first aspect of the present invention, the first imaging unit may be formed on a rigid substrate, and the second imaging unit may be formed on a flexible substrate.

[12] In the first aspect of the present invention, the first imaging unit may be formed on a first flexible substrate, and the second imaging unit may be formed on a second flexible substrate.

[13] In the first aspect of the invention, the first imaging unit is formed on a part of the flexible substrate, and the second imaging unit is another part of the flexible substrate. It may be formed.

[14] A radiographic imaging system according to a second aspect of the present invention is a radiographic imaging system including a radiation source, a radiation detection device, and a control device that controls at least the radiation detection device. The radiation from the radiation source absorbs at least a part of the soft line component and detects at least the radiation, and the radiation from the radiation source transmitted through the first imaging unit and the subject. And a second imaging unit that converts to a radiation image and outputs the radiation image.

[15] In the second aspect of the present invention, the control device includes a synchronization unit that sets a start timing of a charge accumulation period in the second imaging unit based on detection of radiation in the first imaging unit. It may be.

[16] In the second aspect of the present invention, the control device controls the radiation source and the radiation detection device, and controls irradiation energy of the radiation source based on at least a detection signal from the first imaging unit. You may make it have an irradiation energy control part characterized by doing.

[17] In the second aspect of the present invention, the control device controls the radiation source and the radiation detection device, and radiation emitted from the radiation source based on at least a detection signal from the first imaging unit. You may make it have an irradiation field control part characterized by controlling the irradiation range.

[18] In the second aspect of the present invention, the control device includes an amplifier gain control unit that controls an amplifier gain in the second imaging unit based on at least a detection signal from the first imaging unit. Also good.

  As described above, according to the radiation detection apparatus and the radiographic imaging system of the present invention, a general-purpose radiation source can be used without using an expensive radiation source, and the object can be applied to the subject with a simple configuration. Ineffective exposure can be avoided, and it can be applied to various variations, which can contribute to the spread of radiography.

It is a block diagram which shows the radiographic imaging system which concerns on this Embodiment. It is a block diagram which mainly shows the structure of a radiation irradiation apparatus. FIG. 3A is a perspective view showing a part of the first radiation detection panel, and FIG. 3B is a perspective view showing a part of the second radiation detection panel. 4A is an explanatory diagram illustrating a first aspect of the first imaging unit (or the second imaging unit), FIG. 4B is an explanatory diagram illustrating the second aspect, and FIG. 4C is an explanatory diagram illustrating the third aspect. 4D is an explanatory view showing the fourth aspect, FIG. 4E is an explanatory view showing the fifth aspect, and FIG. 4F is an explanatory view showing the sixth aspect. It is a circuit diagram which shows a 1st imaging part (or 2nd imaging part) and a 1st read-out circuit (or 2nd read-out circuit). It is a block diagram which mainly shows the structure of a 1st radiation detection panel and a 2nd radiation detection panel. It is a block diagram which mainly shows the structure of a 1st system control part. FIG. 8A is a block diagram showing the configuration of the first type synchronization unit, and FIG. 8B is a block diagram showing the configuration of the second type synchronization unit. It is a flowchart which shows the process operation | movement of the 1st moving image imaging process (1st radiation detection panel) of a 1st system control part. It is a flowchart which shows the process operation | movement of the 1st moving image imaging process (2nd radiation detection panel) of a 1st system control part. It is a time chart which shows a 1st moving image shooting process. It is a flowchart which shows the 2nd moving image imaging process of a 1st system control part. It is a time chart which shows a 2nd moving image imaging | photography process. It is a block diagram which mainly shows the structure of a 2nd system control part. It is a block diagram which mainly shows the structure of a 3rd system control part. It is a flowchart which shows the moving image shooting process of a 3rd system control part. It is a time chart which shows the moving image shooting process of a 3rd system control part. It is explanatory drawing which shows one form of the radiation detection apparatus in the time of still image photography. It is a flowchart which shows the still image shooting process of a 3rd system control part. It is a time chart which shows the still picture photographing processing of the 3rd system control part. It is explanatory drawing which shows one form of the radiation detection apparatus in the case of energy sub imaging | photography. It is a flowchart which shows the energy sub imaging | photography process of a 3rd system control part. It is a time chart which shows the energy sub imaging | photography process of a 3rd system control part. It is a block diagram which mainly shows the structure of a 4th system control part. It is a block diagram which mainly shows the structure of a 5th system control part. It is a block diagram which shows the radiographic imaging system using a 1st radiation detection apparatus. It is a block diagram which shows the radiographic imaging system using a 2nd radiation detection apparatus. It is a block diagram which shows the radiographic imaging system using a 3rd radiation detection apparatus. It is a block diagram which shows the radiographic imaging system using a 4th radiation detection apparatus.

  Embodiments of a radiation detection apparatus and a radiation image capturing system according to the present invention will be described below with reference to FIGS.

  As shown in FIGS. 1 and 2, the radiographic imaging system 10 according to the present exemplary embodiment detects a radiation irradiation device 14 having a radiation source 12 (see FIG. 2) and radiation 16 from the radiation source 12. It has the radiation detection apparatus 18 which converts into a radiation image, and the system control part 20 which controls the radiation detection apparatus 18 at least. The system control unit 20 may or may not control the radiation irradiation device 14 depending on the specification. Therefore, in FIG.1 and FIG.2, the wiring between the radiation irradiation apparatus 14 and the system control part 20 is shown with a broken line.

  A console 22 is connected to the system control unit 20 so that data communication with the console 22 is possible. The console 22 is connected to a monitor 24 for image observation and image diagnosis and an input device 26 (keyboard, mouse, etc.) for operation input. An operator (physician or radiographer) uses the input device 26 to set a radiation dose or a radiographic frame rate suitable for the current situation in a surgical operation or catheter insertion operation while observing a moving image. Data input using the input device 26 and data created and edited by the console 22 are input to the system control unit 20. In addition, a moving image or a still image of a radiographic image from the system control unit 20 is supplied to the console 22 and displayed on the monitor 24.

  As illustrated in FIG. 2, the radiation irradiation apparatus 14 is based on the radiation source 12, the radiation source control unit 28 that controls the radiation source 12 based on the instruction from the system control unit 20, and the instruction from the system control unit 20. And an automatic collimator unit 30 that widens or narrows the irradiation range of the radiation 16.

  As illustrated in FIG. 1, the radiation detection device 18 includes two radiation detection panels (a first radiation detection panel 32A and a second radiation detection panel 32B).

  When two radiation detection panels are used, for example, the second radiation detection panel 32B is placed on the imaging table 34, and the second is placed on the back surface of the subject 36 (the surface opposite to the radiation irradiation device 14 side). The radiation detection panel 32B is positioned, and the first radiation detection panel 32A is positioned on the front surface of the subject 36 (the surface on the radiation irradiation device 14 side). That is, the first radiation detection panel 32A and the second radiation detection panel 32B are installed so as to sandwich the subject 36. In this case, the first radiation detection panel 32A may be placed on the subject 36 or held by the subject 36 or an operator. Of course, the first radiation detection panel 32A and the second radiation detection panel 32B are fixed to a moving mechanism 40 having a plurality of hinges 38, and the first radiation detection panel 32A and the second radiation detection panel 32B are separated by an arbitrary distance. May be positioned so as to be substantially parallel. Thereby, the burden on the subject 36 can be reduced.

  As described above, radiation imaging (for example, video imaging) of the subject 36 is performed by irradiating the subject 16 with the radiation 16 with the subject 36 sandwiched between the first radiation detection panel 32A and the second radiation detection panel 32B. ) Is performed.

  Here, as shown in FIG. 3A, the first radiation detection panel 32A includes a first housing 42A made of a material that allows the radiation 16 to pass therethrough, and at least the first imaging unit 44A is provided inside the first housing 42A. Have The first imaging unit 44A absorbs at least a soft ray component of the radiation 16 from the radiation source 12, converts the radiation 16 into a first radiation image, and outputs the first radiation image. Therefore, the subject 36 is prevented from being exposed to the soft line component that does not contribute to the diagnosis, and the ineffective exposure to the subject 36 can be reduced.

  In the first housing 42A, a first battery 46A as a power source, a first panel control unit 48A for driving and controlling at least the first imaging unit 44A, and a first radiation image from the first imaging unit 44A are further displayed. A first transmitter / receiver 50 </ b> A that transmits and receives a signal to / from the outside by wire or wireless is accommodated. The first radiographic image output from the first transceiver 50A is input to the system control unit 20.

  The first panel controller 48A and the first transmitter / receiver 50A have a lead plate on the irradiation surface side of the first panel controller 48A and the first transmitter / receiver 50A in order to avoid damage caused by the radiation 16 being irradiated. Etc. are preferably arranged.

  On the other hand, the 2nd radiation detection panel 32B is provided with the 2nd housing | casing 42B which consists of a material which permeate | transmits the radiation 16, as shown to FIG. 3B. Inside the second housing 42B, a second imaging unit 44B that converts at least the radiation 16 from the radiation source 12 that has passed through the subject 36 into a second radiation image and outputs the second radiation image, and one surface of the second imaging unit 44B. A grid 52 that is disposed opposite to the surface of the second housing 42B near the irradiation surface 42a and that removes the scattered radiation 16 of the radiation 16 from the subject 36 and the other surface of the second imaging unit 44B. And a lead plate 54 that absorbs backscattered rays of the radiation 16. In addition, you may comprise the irradiation surface 42a of the 2nd housing | casing 42B as the grid 52. FIG.

  The second radiation detection panel 32B further includes a second battery 46B as a power source, a second panel control unit 48B that drives and controls at least the second imaging unit 44B, and a second radiation image from the second imaging unit 44B. And a second transceiver 50B that transmits and receives a signal including the signal to and from the outside by wire or wirelessly. The second radiographic image output from the second transceiver 50B is input to the console 22 via the system control unit 20 and is displayed on the monitor 24. That is, when still image shooting is performed, since one second radiation image is input to the system control unit 20, the second radiation image is displayed as a still image on the monitor 24. When moving image shooting is performed, second radiation images based on radiation shooting at a set frame rate are sequentially input to the system control unit 20, so that the moving image of the second radiation image is displayed in real time on the monitor 24. It will be projected in.

  Also in the second radiation detection panel 32B, the second panel control unit 48B and the second transceiver 50B are prevented from being damaged by the radiation 16 being irradiated to the second panel control unit 48B and the second transceiver 50B. It is preferable to arrange a lead plate or the like on the irradiation surface side of the transceiver 50B.

  Here, configuration examples of the first imaging unit 44A and the second imaging unit 44B will be described with reference to FIGS. 4A to 4F.

  The first imaging unit 44A and the second imaging unit 44B can employ the first to sixth modes shown in FIGS. 4A to 4F. For example, the first imaging unit 44A employs the first aspect, the second imaging unit 44B employs the second aspect, and the like.

  As shown in FIG. 4A, the first mode includes a sensor substrate 56 and a scintillator 58 installed on one surface of the sensor substrate 56 (a surface on the incident side of the radiation 16).

  The sensor substrate 56 includes, for example, a base body 60 and a photodiode portion 62 formed on one surface of the base body 60 (surface on the incident side of the radiation 16). As the substrate 60, for example, a glass substrate 64 is used. The photodiode unit 62 can employ a configuration in which a large number of photodiodes made of amorphous silicon (a-Si) are arranged in accordance with pixels. In this case, the scintillator 58 and the photodiode unit 62 constitute a first imaging unit 44A (second imaging unit 44B).

  Further, on one surface of the glass substrate 64, a plurality of gate lines and a plurality of signal lines for reading out the charges photoelectrically converted by the photodiode portion 62 and TFTs (thin film transistors) corresponding to the pixels are formed. .

  The substrate 60 may be a crystalline silicon substrate or a SiC substrate (silicon carbide substrate) instead of the glass substrate 64. In this case, a CMOS circuit including a TFT may be formed.

  As a constituent material of the scintillator 58, it is important that the specific gravity is heavy. Since the absorption (photoelectric effect) of the radiation 16 increases in proportion to the fifth power of the atomic number, the scintillator 58 made of heavier constituent elements can increase the radiation absorption capacity per unit area. Further, high conversion energy efficiency is important for setting sensitivity in the film, the first imaging unit 44A, and the second imaging unit 44B. Therefore, as the scintillator 58, materials shown in Table 1 below can be used. The scintillator 58 of the first imaging unit 44A preferably absorbs at least a part of the soft line component in the radiation 16 from the radiation source 12. In this case, for example, it is preferable to absorb the soft wire component better than the hard wire component. Therefore, in Table 1 below, it is preferable to use a material having a small K absorption edge, that is, a material indicated by *. In particular, considering the sensitivity of amorphous silicon (a-Si), it is more preferable to use a composition whose emission color is green.

  Of course, both the scintillator 58 of the first imaging unit 44A and the scintillator 58 of the second imaging unit 44B may be made of the same material. In this case, since the hard line component is absorbed when the thickness of the first imaging unit 44A (or the thickness of the first radiation detection panel 32A) is increased, the thickness of the first imaging unit 44A (or the first radiation detection panel 32A) is also absorbed. The thickness is preferably smaller than the thickness of the second imaging unit 44B (or the thickness of the second radiation detection panel 32B).

  The first imaging unit 44A (or the first radiation detection panel 32A) is intended to absorb soft line components that do not contribute to imaging (diagnosis), but absorbs soft line components more than necessary. In this sense, the thickness of the first imaging unit 44A (or the first radiation detection panel 32A) is set to be the same as that of the second imaging unit 44B. It is preferable to make it thinner than the thickness (or the thickness of the second radiation detection panel 32B) and not absorb the soft wire component more than necessary.

  As shown in FIG. 4B, the second mode has substantially the same configuration as the first mode described above, but uses an organic photoconductor 66 (OPC: Organic Photo Conductors) instead of the photodiode unit 62. It is different in point. An organic photoconductor 66 is installed between the sensor substrate 56 and the scintillator 58. In this case, the scintillator 58 and the organic photoconductor 66 constitute a first imaging unit 44A (second imaging unit 44B).

  The sensor substrate 56 includes, for example, a base 60 and a plurality of gate lines, a plurality of signal lines, and organic TFTs corresponding to pixels for reading out the charges photoelectrically converted by the organic photoconductor 66 on one surface of the base 60. A thin film transistor made of an organic material) or an oxide semiconductor (for example, InGaZnOx: IGZO) is formed.

  As the substrate 60, for example, a resin substrate 68 can be used. Alternatively, instead of the resin substrate 68, a crystalline silicon substrate or a SiC substrate (silicon carbide substrate) may be used. In this case, a CMOS circuit including a TFT may be formed.

  As shown in FIG. 4C, the third mode has substantially the same configuration as the first mode described above, but differs in that the sensor substrate 56 is installed on the radiation 16 incident side.

  As shown in FIG. 4D, the fourth mode has substantially the same configuration as the second mode described above, but differs in that the sensor substrate 56 is installed on the radiation 16 incident side.

  As shown in FIG. 4E, the fifth mode has substantially the same configuration as the first mode described above, but replaces the scintillator 58 and the photodiode unit 62 with amorphous selenium that directly converts the radiation 16 into an electrical signal. The difference is that the solid detection element 70 is made of a substance such as (a-Se). A bias voltage Vb is applied to the solid state detection element 70.

  As shown in FIG. 4F, the sixth mode has substantially the same configuration as the third mode described above, but replaces the scintillator 58 and the photodiode unit 62 with amorphous selenium that directly converts the radiation 16 into an electrical signal. The difference is that the solid detection element 70 is made of a substance such as (a-Se).

  Next, as an example, the readout circuit (first readout circuit 78A) of the first imaging unit 44A (second imaging unit 44B) when the indirect conversion type first radiation detection panel 32A (second radiation detection panel 32B) is employed. The configuration of the second readout circuit 78B) will be described in detail with reference to FIG.

  The first imaging unit 44A includes, for example, an array of thin film transistors (hereinafter referred to as TFTs 84) in which a photoelectric conversion layer 82 in which each pixel 80 made of a material such as a-Si that converts visible light into an electrical signal is formed. It has a structure arranged on the top. In this case, since charges generated by converting visible light into electrical signals (analog signals) are accumulated in each pixel 80, for example, by sequentially turning on the TFT 84 for each row, the charges are used as image signals. Can be read.

  The first readout circuit 78A includes a TFT 84 connected to each pixel 80, a gate line 86 connected to the TFT 84 and extending parallel to the row direction, and a signal line 88 connected to the TFT 84 and extending parallel to the column direction. . Each gate line 86 is connected to a line scan driver 90, and each signal line 88 is connected to a multiplexer 92. Control signals Von and Voff for controlling on / off of the TFTs 84 arranged in the row direction are supplied from the line scanning drive unit 90 to the gate line 86. In this case, the line scan driver 90 includes a plurality of switches SW1 for switching the gate lines 86, and an address decoder 94 for outputting a selection signal for selecting the switches SW1. The address decoder 94 is supplied with an address signal from the first panel control unit 48A.

  In addition, the charge held in each pixel 80 flows out to the signal line 88 via the TFTs 84 arranged in the column direction. This electric charge is amplified by the charge amplifier 96. A multiplexer 92 is connected to the charge amplifier 96 via a sample and hold circuit 98.

  That is, the read charges in each column are input to the charge amplifiers 96 in each column via the signal lines 88. Each charge amplifier 96 includes an operational amplifier 100, a capacitor 102, and a switch 104. When the switch 104 is off, the charge amplifier 96 converts the charge signal input to one input terminal of the operational amplifier 100 into a voltage signal and outputs the voltage signal. The charge amplifier 96 amplifies and outputs the electrical signal with the gain set by the first panel control unit 48A. Information relating to the gain of the charge amplifier 96 (gain setting information) is supplied from the system control unit 20 to the first panel control unit 48A. The first panel control unit 48A sets the gain of the charge amplifier 96 based on the supplied gain setting information.

  The other input terminal of the operational amplifier 100 is connected to GND (ground potential) (ground). When all the TFTs 84 are turned on and the switch 104 is turned on, the charge accumulated in the capacitor 102 is discharged by the closed circuit of the capacitor 102 and the switch 104 and the charge accumulated in the pixel 80 is closed. It is swept out to GND (ground potential) via the switch 104 and the operational amplifier 100. The operation of turning on the switch 104 of the charge amplifier 96 to discharge the charge stored in the capacitor 102 and sweeping out the charge stored in the pixel 80 to GND (ground potential) is a reset operation (empty reading operation). Call it. In particular, an operation of sweeping out charges of all pixels to GND is called an all pixel reset operation. That is, in the reset operation, the voltage signal corresponding to the charge signal stored in the pixel 80 is discarded without being output to the multiplexer 92.

  The multiplexer 92 includes a plurality of switches SW2 for switching the signal line 88 and an address decoder 106 for outputting a selection signal for selecting the switch SW2. The address decoder 106 is supplied with an address signal from the first panel control unit 48A. An A / D converter 108 is connected to the multiplexer 92, and a radiation image converted into a digital signal by the A / D converter 108 is supplied to the first panel control unit 48A.

  Since the configurations of the second imaging unit 44B and the second readout circuit 78B are substantially the same as the configurations of the first imaging unit 44A and the first readout circuit 78A described above, a duplicate description thereof will be omitted.

  Note that the TFT 84 functioning as a switching element may be realized in combination with another imaging element such as a CMOS (Complementary Metal-Oxide Semiconductor) image sensor. Furthermore, it can be replaced with a CCD (Charge-Coupled Device) image sensor that transfers charges while shifting them with a shift pulse corresponding to a gate signal referred to as a TFT.

  As shown in FIG. 6, the first panel controller 48A of the first radiation detection panel 32A includes a first address signal generator 110A for the first readout circuit 78A, a first image memory 112A, and a first panel ID. And a memory 114A.

  Similarly to the first panel control unit 48A, the second panel control unit 48B of the second radiation detection panel 32B also includes a second address signal generation unit 110B for the second readout circuit 78B, a second image memory 112B, 2 panel ID memory 114B.

  110 A of 1st address signal generation parts, for example, the moving image read-out control information (1st moving image read-out control information Sa1 mentioned later) of the 1st radiographic image from the system control part 20, and the energy subtraction (henceforth energy sub) of 1st radiographic image. Based on the read control information (first energy sub read control information Sc1 to be described later), the address decoder 94 of the line scan driver 90 and the address decoder 106 of the multiplexer 92 in the first read circuit 78A shown in FIG. Supply signal. The first moving image read control information Sa1 and the first energy sub read control information Sc1 are, for example, a progressive mode, an interlace mode (odd row read mode, even row read mode, second row read mode, third row read mode, etc.), binning mode Information about the readout mode indicating (1 pixel / 4 pixel readout mode, 1 pixel / 6 pixel readout mode, 1 pixel / 9 pixel readout mode, etc.) is included. For example, in the 1-pixel / 4-pixel readout mode, two adjacent gate lines are simultaneously activated (set to Von), and two adjacent signal lines are selected at the same time. In this mode, charges for pixels are mixed and read as one pixel. The first address signal generation unit 110A generates an address signal corresponding to the mode indicated by the first moving image readout control information Sa1 and the first energy sub readout control information Sc1, and the address decoder 94 and the multiplexer 92 of the line scan driver 90 The data is output to the address decoder 106. The first moving image readout control information Sa1 and the first energy sub readout control information Sc1 are created by the system control unit 20 based on, for example, an operation input from the operator, and are transmitted to the first panel control unit 48A of the first radiation detection panel 32A. Entered.

  As the first moving image readout control information Sa1 and the first energy sub readout control information Sc1 supplied from the system control unit 20, in addition to the information related to the readout mode (readout mode information), the imaging range information specifying the imaging range is also included. included. The imaging range information includes, for example, the address of the gate line 86 and the address of the signal line 88 included in the set imaging range when the operator sets the imaging range of a moving image, for example, using the input device 26 and the monitor 24. It is done. Of course, the start address (number) and end address (number) of the gate line 86 included in the imaging range and the start address (number) and end address (number) of the signal line 88 may be used. If the readout mode information is, for example, an odd-numbered row readout mode (decimation), odd-numbered gate lines 86 are sequentially selected from among the gate lines 86 included in the imaging range of the first imaging unit 44A, and the first imaging unit is selected. The signal charges from the signal line 88 included in the 44A imaging range are sequentially transferred toward the A / D converter 108 without being synthesized. If the readout mode information is, for example, a 1-pixel / 4-pixel readout mode (binning), for example, two gate lines 86 included in the imaging range are sequentially selected, and signal charges from the signal lines 88 included in the imaging range are combined. (In this case, signal charges from two adjacent signal lines 88 are combined), that is, signal charges for four pixels are combined and sequentially transferred to the A / D converter 108. Become.

  The same applies to the second address signal generator 110B. For example, the moving image reading control information (second moving image reading control information Sa2 to be described later) from the system control unit 20 and the stationary state of the second radiation image. Lines in the second readout circuit 78B shown in FIG. 5 based on image readout control information (still image readout control information Sb described later) and energy sub readout control information (second energy sub readout control information Sc2 described later) of the second radiation image. Address signals are supplied to the address decoder 94 of the scan driver 90 and the address decoder 106 of the multiplexer 92.

  The first image memory 112A stores the first radiation image D1 from the first readout circuit 78A, and the second image memory 112B stores the second radiation image D2 from the second readout circuit 78B. The first panel ID memory 114A stores panel ID information for specifying the first radiation detection panel 32A, and the second panel ID memory 114B stores panel ID information for specifying the second radiation detection panel 32B. To do.

  The first transceiver 50A transmits the panel ID information stored in the first panel ID memory 114A and the first radiation image D1 stored in the first image memory 112A to the system control unit 20 by wired communication or wireless communication. The second transceiver 50B transmits the panel ID information stored in the second panel ID memory 114B and the second radiation image D2 stored in the second image memory 112B to the system control unit 20 by wired communication or wireless communication.

  Next, some specific examples of the system control unit 20 of the radiographic imaging system 10 will be described with reference to FIGS.

  First, the system control unit according to the first specific example (hereinafter referred to as the first system control unit 20A) includes a moving image shooting processing unit 116 and a synchronization unit 118, as shown in FIG.

  As described above (see FIG. 1), the moving image shooting is performed in a state where the second radiation detection panel 32B is installed on the back side of the subject 36 and the first radiation detection panel 32A is installed on the front surface of the subject 36. This moving image shooting is executed mainly by the linkage of the moving image shooting processing unit 116 and the synchronization unit 118.

  The moving image capturing processing unit 116 performs control so as to execute radiation imaging for obtaining a moving image based on, for example, an operation input of a moving image capturing request by an operator or an input of a moving image capturing request from another device.

  The moving image shooting processing unit 116 includes a moving image parameter setting unit 120, a moving image parameter history storage unit 122, and a moving image transfer unit 124.

  The moving image parameter setting unit 120 is a moving image parameter history storage unit 122 when new parameters (frame rate, readout mode, shooting range, etc.) are set by an operation input from an operator during moving image shooting. The newly set frame rate, readout mode, shooting range, etc. are stored as the latest parameters.

  For example, when a readout mode, an imaging range, or the like for obtaining the first radiation image D1 used for moving image capturing control is newly set, the first including the newly set readout mode information, imaging range information, etc. The moving image readout control information Sa1 is output to the first radiation detection panel 32A. Similarly, when a readout mode, an imaging range, or the like is newly set to obtain a moving image of the radiographic image (second radiographic image D2) of the subject 36, the newly set readout mode information, imaging range information, etc. The second moving image readout control information Sa2 that is included is output to the second radiation detection panel 32B.

  The moving image parameter history storage unit 122 stores a frame rate set for a predetermined period in the past from the present time among the frame rates set so far.

  Since the first system control unit 20A is not electrically connected to the radiation irradiation device 14, the setting of the irradiation energy (and the frame rate) is directly performed on the radiation irradiation device 14.

  The moving image transfer unit 124 receives the second radiation images D2 sequentially supplied from the second radiation detection panel 32B and transfers them to the console 22. The console 22 displays the second radiation image D2 sequentially transferred on the monitor 24. As a result, the moving image of the second radiation image D2 is displayed on the monitor 24.

  The synchronization unit 118 sets the start timing of the charge accumulation period in the second imaging unit 44B based on at least the detection of the radiation 16 in the first imaging unit 44A.

  Specifically, in the first radiation image D1 from the first radiation detection panel 32A, the average gray value of a plurality of specific pixels (specific pixel group) is compared with a preset threshold value, and the average gray value is determined. When the threshold value is exceeded, the start timing of the exposure period on the second radiation detection panel 32B is set.

  Here, the setting of the start timing includes the following cases. For example, the time when the average gray value is equal to or greater than the threshold value is set as the start time of the exposure period in the second radiation detection panel 32B. Alternatively, the time when a preset time has elapsed from the time when the average gray value becomes equal to or greater than the threshold value is set as the start time of the exposure period in the second radiation detection panel 32B. Alternatively, for example, the above-described reset operation is performed in the second radiation detection panel 32B when the average gray value becomes equal to or greater than the threshold value, and the time when the reset operation ends is set as the start time of the exposure period.

  As the average gray value of the specific pixel group, for example, the average gray value for four pixels in 2 rows and 2 columns in the central portion of the first radiation detection panel 32A may be obtained. The radiation image D1 only needs to be data for four pixels. Therefore, the reading speed of the first radiation image D1 can be significantly increased, and the radiation 16 from the radiation source 12 is irradiated onto the first radiation conversion panel 32A. It is possible to detect that the radiation 16 has been emitted during a slight time interval (for example, 0.5 to 5 msec) from the time point. Therefore, for example, even when the frame rate of moving image shooting is 60 frames / second (about 17 msec / 1 frame), it can be reliably detected that the radiation 16 has been irradiated.

  The synchronization unit 118 employs, for example, two methods. As shown in FIG. 8A, the first method synchronization unit 118 includes a first average gray value comparison unit 126A, a previous register Ra, a current register Rb, and an exposure. A period determination unit 128.

  The first average gray value comparison unit 126A compares the average gray value Da of the specific pixel group with a preset threshold value Db, and if the average gray value Da is less than the threshold value Db, An initial value “0” indicating that the radiation 16 has not arrived is stored, and if the average gray value Da is equal to or greater than the threshold value Db, a value “1” indicating that the radiation 16 has reached the current register Rb. Is stored.

  The exposure period determination unit 128 compares the value of the previous register Ra with the value of the current register Rb, and detects the second radiation when the value of the previous register Ra is “0” and the value of the current register Rb is “1”. An exposure start signal Sd is output to the panel 32B. When the previous value of the register Ra is “1” and the current value of the register Rb is “0”, an exposure end signal Se is output to the second radiation detection panel 32B. In addition, after outputting the exposure start signal Sd or the exposure end signal Se, the exposure period determination unit 128 stores the value of the current register Rb in the previous register Ra.

  The second radiation detection panel 32B performs charge accumulation (exposure) based on the input of the exposure start signal Sd, and performs charge read operation based on the input of the exposure end signal Se.

  On the other hand, as shown in FIG. 8B, the second method synchronization unit 118 includes a second average gray value comparison unit 126B. The second average gray value comparison unit 126B compares the average gray value Da of the specific pixel group with a preset threshold value Db, and when the average gray value Da exceeds the threshold value Db, An operation start signal Sf2 is output.

  The second radiation detection panel 32B performs charge accumulation and charge read operations based on the input of the second operation start signal Sf2.

  Here, operations of the two moving image capturing processes (first moving image capturing process and second moving image capturing process) of the radiographic image capturing system 10 having the synchronization unit 118 will be described with reference to FIGS. 9 to 13.

  First, in the operation of the first moving image photographing process using the first method synchronization unit 118, the control for the first radiation detection panel 32A and the control for the second radiation detection panel 32B are performed by the multitask method.

  First, the control for the first radiation detection panel 32A will be described. In step S1 of FIG. 9, the synchronization unit 118 detects the irradiation timing (exposure start and exposure end) of the radiation 16 to the first radiation detection panel 32A. The initial value “0” is stored in each of the two registers (previous register Ra and current register Rb).

  In step S2, the moving image parameter setting unit 120 determines whether or not a readout mode, an imaging range, and the like for obtaining the first radiation image D1 are newly set.

  For example, when the operator newly sets a parameter, the process proceeds to step S3, and the newly set readout mode, shooting range, etc. are stored in the moving image parameter history storage unit 122 as the latest parameter. Next, in step S4, the first moving image readout control information Sa1 including the newly set readout mode and imaging range is output to the first radiation detection panel 32A. The first panel control unit 48A of the first radiation detection panel 32A supplies the input first moving image readout control information Sa1 to the first address signal generation unit 110A.

  When it is determined in step S2 that no new parameter is set, or when the process in step S4 is completed, the process proceeds to the next step S5, and the first system control unit 20A includes the first radiation detection panel 32A. Outputs a first operation start signal Sf1 indicating charge accumulation and charge reading.

  In step S6, the first radiation detection panel 32A performs charge accumulation and charge reading based on the input of the operation start signal Sf from the first system control unit 20A. That is, if the radiation 16 reaches the first radiation detection panel 32A, the arrived radiation 16 is once converted into visible light, for example, by the scintillator 58 of the first imaging unit 44A, and each pixel 80 of the first imaging unit 44A. , Visible light is photoelectrically converted, and an amount of electric charge corresponding to the amount of light is accumulated. If the radiation 16 has not reached, little charge is accumulated in each pixel 80.

  In the subsequent readout period, the first address signal generator 110A creates an address signal according to the supplied first moving image readout control information Sa1 (imaging range information, readout mode information, etc.), and the first readout circuit 78A The data is output to the address decoder 94 of the line scan driver 90 and the address decoder 106 of the multiplexer 92. The first readout circuit 78A reads out charges according to the first moving image reading control information Sa1, and outputs the first radiation image D1 for moving images by using, for example, the FIFO method using the first image memory 112A. As the first radiation image D1, for example, as described above, since it is only data of a specific pixel group (for example, four pixels in the central portion of the first radiation detection panel 32A), it is read out at high speed. The first radiation image D1 from the first radiation detection panel 32A is supplied to the synchronization unit 118 of the first system control unit 20A.

  In step S7, the first average gray value comparison unit 126A of the synchronization unit 118 compares the average gray value Da of the specific pixel group with a preset threshold value Db, and the average gray value Da is less than the threshold value Db. If there is, the process proceeds to step S9, and the initial value “0” indicating that the radiation 16 has not reached is stored in the register Rb this time. If the average gray value Da is greater than or equal to the threshold value Db, the process proceeds to step S8, and a value “1” indicating that the radiation 16 has arrived is stored in the register Rb this time.

  In step S10, the exposure period determination unit 128 of the synchronization unit 118 determines whether or not the value of the previous register Ra and the value of the current register Rb are different. If the values are different, the process proceeds to the next step S11, and the exposure period determination unit 128 determines whether or not the irradiation of the radiation 16 is started. This determination is made based on whether the value of the previous register Ra is “0” and the value of the current register Rb is “1”. If it is determined that the irradiation of the radiation 16 has started, the process proceeds to the next step S12, and the exposure period determination unit 128 outputs an exposure start signal Sd to the second radiation detection panel 32B. If it is determined in step S11 that the irradiation of the radiation 16 has not started, that is, if it is determined that the value of the previous register Ra is “1” and the value of the current register Rb is “0”, the radiation 16 In step S13, the exposure end signal Se is output to the second radiation detection panel 32B.

  If it is determined in step S10 that the previous value of the register Ra and the current value of the register Rb are the same, or when the process in step S12 is completed, or when the process in step S13 is completed. Proceeding to the next step S14, the value of the current register Rb is stored in the previous register Ra.

  In the next step S15, the first system control unit 20A determines whether or not there is a moving image shooting end request. If there is no end request for moving image shooting, the process returns to step S2 to repeat the processes after step S2. On the other hand, when it is determined in step S15 that there is a request for ending moving image shooting, the control of the first radiation detection panel 32A by the first method synchronization unit 118 ends.

  Next, control for the second radiation detection panel 32B will be described with reference to FIG.

  First, in step S101 of FIG. 10, the first system control unit 20A stores an initial value (= 1) in the counter k of the number of photographing times.

  In step S102, the moving image parameter setting unit 120 determines whether or not a readout mode, an imaging range, and the like for obtaining a moving image of the second radiation image D2 are newly set.

  For example, when the operator newly sets a parameter, the process proceeds to step S103, and the newly set readout mode, shooting range, and the like are stored in the moving image parameter history storage unit 122 as the latest parameter. Next, in step S104, the second moving image readout control information Sa2 including the newly set readout mode and imaging range is output to the second radiation detection panel 32B. The second panel control unit 48B of the second radiation detection panel 32B supplies the input second moving image readout control information Sa2 to the second address signal generation unit 110B.

  When it is determined in step S102 that no new parameter has been set, or when the processing in step S104 is completed, the process proceeds to the next step S105, where the second radiation detection panel 32B performs exposure from the synchronization unit 118. Wait for input of start signal Sd.

  When the exposure start signal Sd is input, the process proceeds to the next step S106, and the second radiation detection panel 32B performs charge accumulation (exposure). That is, the radiation 16 that has passed through the first radiation detection panel 32A and the subject 36 is temporarily converted into visible light, for example, by the scintillator 58 of the second imaging unit 44A, and the visible light is photoelectrically generated in each pixel 80 of the second imaging unit 44A. As a result of conversion, an amount of electric charge corresponding to the amount of light is accumulated. At this time, the radiation 16 also passes through the first radiation detection panel 32A, but the first imaging unit 44A accommodated in the first radiation detection panel 32A has at least a soft line of the radiation 16 from the radiation source 12. Since the component is absorbed, the subject 36 is prevented from being exposed to the soft line component that does not contribute to the diagnosis, and the ineffective exposure to the subject 36 can be reduced.

  Thereafter, in step S107, input of an exposure end signal Se from the synchronization unit 118 is awaited. When the exposure end signal Se is input, the process proceeds to the next step S108, and the second radiation detection panel 32B performs charge reading. That is, the second address signal generation unit 110B creates an address signal according to the supplied second moving image readout control information Sa2 (imaging range, readout mode, etc.), and the line scanning drive unit 90 in the second readout circuit 78B. Output to the address decoder 94 and the address decoder 106 of the multiplexer 92. The second readout circuit 78B reads out charges in accordance with the second moving image reading control information Sa2, and outputs the second radiation image D2 for moving images using, for example, the FIFO method using the second image memory 112B. The second radiation image D2 from the second radiation detection panel 32B is supplied to the moving image transfer unit 124 of the first system control unit 20A.

  In step S <b> 109, the moving image transfer unit 124 transfers the supplied moving image second radiation image D <b> 2 to the console 22. The console 22 stores the transferred second radiation image D2 in the frame memory and displays it on the monitor 24 as a radiation image obtained by the k-th radiation imaging, that is, a k-th radiation image.

  In step S110, the value of the counter k is updated by +1.

  In step S111, the first system control unit 20A determines whether or not there is a moving image shooting end request. If there is no moving image shooting end request, the process returns to step S102, and the processes in and after step S102 are repeated. Thereby, a moving image of the radiation image at the set frame rate is displayed on the monitor 24. On the other hand, in step S111, when it is determined that there is a request to end moving image shooting, moving image shooting ends.

  In the example of FIG. 11, the first radiation conversion panel 32A outputs the first radiation image D1 with a short period Ta (for example, 0.5 to 5 msec) from, for example, the moving image capturing start time t0. For example, since the radiation 16 has not reached the first radiation detection panel 32A from the output of the first radiation image D1 for the first time to the output of the first radiation image D1 for the sixth time, exposure starts from the synchronization unit 118. The signal Sd is not output.

  In the seventh output of the first radiation image D1, since the radiation 16 has reached the first radiation detection panel 32A, the average gray value Da of the specific pixel group in the first radiation image D1 is the threshold value Db. Thus, the exposure start signal Sd is output from the synchronization unit 118 to the second radiation detection panel 32B.

  The second radiation detection panel 32B performs charge accumulation based on the input of the exposure start signal Sd, performs charge readout based on the subsequent exposure end signal Se, and outputs the second radiation image D2. . In this case, the period from the input time ta of the exposure start signal Sd to the input time tb of the exposure end signal Se is the exposure period Tb, and the period from the input time tb of the exposure end signal Se to the output of the second radiation image D2. Tc is the reading period Tc. Note that the exposure period Tb may be a fixed period set in advance by an operator.

  The above operation is repeated at a cycle indicated by the set frame rate, and the moving image of the second radiation image D2 is displayed on the monitor 24.

  Next, the operation of the second moving image shooting process will be described with reference to FIGS. In the second moving image photographing process, charge accumulation and charge reading in the second radiation detection panel 32B are triggered by the second operation start signal Sf2 first output from the second type synchronization unit 118 as a set frame. This is a method that automatically operates at a rate.

  First, in step S201 in FIG. 12, the first system control unit 20A stores an initial value (= 1) in the counter k of the number of photographing times.

  In step S202, the moving image parameter setting unit 120 determines whether a reading mode, an imaging range, or the like has been newly set. For example, when the operator newly sets a parameter, the process proceeds to step S203, and the newly set readout mode, shooting range, and the like are stored in the moving image parameter history storage unit 122 as the latest parameter. Next, in step S204, the moving image readout control information including the newly set readout mode and imaging range is output to the corresponding radiation detection panel.

  When it is determined in step S202 that no new parameter is set, or when the process in step S204 is completed, the process proceeds to the next step S205, and the first system control unit 20A includes the first radiation detection panel 32A. Outputs a first operation start signal Sf1 indicating charge accumulation and charge reading.

  In step S206, the first radiation detection panel 32A performs charge accumulation and charge reading based on the input of the first operation start signal Sf1 from the first system control unit 20A, as in step S6 of FIG. 9 described above. The first radiation image D1 for moving images is output.

  In step S207, the second average gray value comparison unit 126B of the second method synchronization unit 118 compares the average gray value Da of the specific pixel group with a preset threshold value Db, and the average gray value Da is a threshold. If it is less than the value Db, the process returns to step S202, and the processes after step S202 are repeated.

  Then, when the average gray value Da becomes equal to or greater than the threshold value Db, the process proceeds to step S208, and the second average gray value comparison unit 126B outputs the second operation start signal Sf2 to the second radiation detection panel 32B.

  In step S209, the first system control unit 20A stops the operation of the first radiation detection panel 32A.

  In step S210, it is determined whether or not the value of the counter k exceeds the initial value. If it exceeds, the process proceeds to step S211 and the first system control unit 20A outputs the previous second operation start signal Sf2. It is determined whether or not a time corresponding to the latest frame rate Fr has elapsed. When the time corresponding to the latest frame rate Fr has elapsed since the output time of the previous second operation start signal Sf2, the process proceeds to the next step S212, and the first system control unit 20A transfers the charge to the second radiation detection panel 32B. A second operation start signal Sf2 indicating accumulation and charge reading is output.

  When it is determined in step S210 that the value of the counter k is an initial value, or when the processing in step S212 is completed, the process proceeds to the next step S213, where the second radiation detection panel 32B 1 Based on the input of the second operation start signal Sf2 from the system control unit 20A, charge accumulation and charge readout are performed, and a second radiation image D2 for moving images is output. The second radiation image D2 from the second radiation detection panel 32B is supplied to the moving image transfer unit 124 of the first system control unit 20A.

  In step S <b> 214, the moving image transfer unit 124 transfers the supplied moving image second radiation image D <b> 2 to the console 22. The console 22 stores the transferred second radiation image D2 in the frame memory and displays it on the monitor 24 as a radiation image obtained by the k-th radiation imaging, that is, a k-th radiation image.

  In step S215, the value of the counter k is updated by +1.

  In step S216, the first system control unit 20A determines whether or not there is a moving image shooting end request. If there is no moving image shooting end request, the process returns to step S202, and the processes in and after step S202 are repeated. Thereby, a moving image of the radiation image at the set frame rate is displayed on the monitor 24. On the other hand, in step S216, when it is determined that there is a request to end moving image shooting, moving image shooting ends.

  In the example of FIG. 13, as in the case of FIG. 11, for example, in the output of the first radiation image D1 for the eighth time, the radiation 16 has reached the first radiation detection panel 32A. The average gray value Da of the specific pixel group in D1 is equal to or greater than the threshold value Db, and the second operation start signal Sf2 is output from the synchronization unit 118 to the second radiation detection panel 32B.

  The second radiation detection panel 32B performs charge accumulation (exposure) and charge readout based on the input of the second operation start signal Sf2, and outputs the result as a second radiation image D2. In this case, the exposure period Tb can be set to a certain period preset by an operator. Note that the period from the end of exposure until the second radiation image D2 is output is the readout period Tc.

  The above operation is repeated at a cycle indicated by the set frame rate Fr, and the moving image of the second radiation image D2 is displayed on the monitor 24.

  Thus, in the radiographic imaging system 10 having the synchronization unit 118, it is possible to determine the irradiation start and irradiation stop of the radiation 16 based on the first radiation image D1 from the first radiation detection panel 32A. Even if the irradiation device 14 and the first system control unit 20A are not electrically connected, it is possible to synchronize the photographing timing, and the cost can be greatly reduced. In addition, in the first imaging unit 44A of the first radiation detection panel 32A, at least the soft line component of the radiation 16 from the radiation source 12 is absorbed. The subject 36 is prevented from being exposed to the soft line component that does not contribute to the diagnosis, and invalid exposure to the subject 36 can be reduced.

  Next, a system control unit (hereinafter referred to as a second system control unit 20B) according to a second specific example will be described with reference to FIG.

  The second system control unit 20B has substantially the same configuration as the first system control unit 20A described above, but differs in that it further includes an amplifier gain control unit 130 as shown in FIG.

  The amplifier gain control unit 130 controls the amplifier gain of the second readout circuit 78B based on at least the first radiation image D1 from the first imaging unit 44A.

  Specifically, the amplifier gain control unit 130 includes a first information table 132, a first average gray value calculation unit 134, a first difference calculation unit 136, and a gain setting information creation unit 138.

  In the first information table 132, the optimum average gray value (reference average gray value) of the first radiation image D1 for each imaging region is registered. The reference average gray value is an average gray value of a plurality of specific pixels (specific pixel group) of the first radiation image D1, and is obtained in advance by experiments or simulations.

  The first average gray value calculator 134 calculates the average gray value of the specific pixel group in the first radiation image D1 from the first radiation detection panel 32A. The first difference calculation unit 136 reads the reference average gray value corresponding to the current imaging region from the first information table 132, and the read reference average gray value and the average gray value from the first average gray value calculation unit 134. The difference value of is calculated.

  The gain setting information creating unit 138 creates gain setting information Sg indicating how much the gain of the charge amplifier 96 is to be increased or decreased based on the obtained difference value. For example, if the difference value obtained from the average gray value-reference average gray value is -ΔG, radiation 16 having an irradiation energy lower than the currently set irradiation energy by an amount corresponding to ΔG is emitted from the radiation source 12. Since it can be estimated that the light is emitted, gain setting information Sg for increasing the gain of the charge amplifier 96 in the second radiation detection panel 32B by an amount corresponding to the difference value ΔG is created. On the other hand, if the difference value obtained from the average gray value-the reference average gray value is + ΔG, the radiation 16 having an irradiation energy higher than the currently set irradiation energy by an amount corresponding to ΔG from the radiation source 12. Therefore, the gain setting information Sg for reducing the gain of the charge amplifier 96 in the second radiation detection panel 32B by an amount corresponding to the difference value ΔG is generated.

  The obtained gain setting information Sg is supplied to the second panel control unit 48B of the second radiation detection panel 32B. The second panel control unit 48B sets the gain of the charge amplifier 96 of the second readout circuit 78B based on the supplied gain setting information Sg. As a result, where the irradiation energy of the radiation 16 to the subject 36 should be a constant irradiation energy, there is a shift in the arrival detection timing of the radiation 16 on the first radiation detection panel 32A in each frame, For example, even if variations occur due to a temperature rise of the radiation source 12 or the like, variations in shading or the like hardly occur in the moving image displayed on the monitor 24. That is, it is possible to obtain a moving image having the same shade as when the subject 36 is irradiated with a constant irradiation energy. In addition, since it is not necessary to control the irradiation energy of the radiation 16 from the radiation source 12 and the gain of the charge amplifier 96 may be set according to the difference value, the moving image displayed on the monitor 24 has variations in light and shade. It can be reduced quickly and easily.

  Next, a system control unit (hereinafter referred to as a third system control unit 20C) according to a third specific example will be described with reference to FIGS.

  As shown in FIG. 15, the third system control unit 20 </ b> C is electrically connected to the radiation irradiation device 14, unlike the first system control unit 20 </ b> A and the second system control unit 20 </ b> B described above.

  The third system control unit 20C includes the above-described moving image shooting processing unit 116, irradiation energy control unit 140, still image shooting processing unit 142, and energy sub shooting processing unit 144.

  The irradiation energy control unit 140 controls the irradiation energy of the radiation 16 emitted from the radiation source 12 based on at least the first radiation image D1 from the first imaging unit 44A during moving image shooting.

  Specifically, the irradiation energy control unit 140 includes a second information table 146, a second average gray value calculation unit 148, and a second difference calculation unit 150. In the second information table 146, average gray values corresponding to a plurality of irradiation energies used are registered. The average gray value is an average gray value of a plurality of specific pixels (specific pixel group) of the first radiation image D1, and is obtained in advance by experiments or simulations. The second average gray value calculator 148 calculates the average gray value of the specific pixel group in the first radiation image D1 from the first radiation detection panel 32A. The second difference calculation unit 150 reads out the average gray value corresponding to the currently set moving image shooting irradiation energy from the second information table 146, and the read average gray value and the average gray value from the average gray value calculation unit. The difference value is calculated. This difference value Sh is supplied to the radiation source controller 28 of the radiation irradiation apparatus 14 (see FIG. 2).

  The radiation source control unit 28 corrects the irradiation energy based on the difference value Sh from the third system control unit 20C (irradiation energy control unit 140). In moving image shooting, radiation is emitted at short time intervals, and therefore radiation 16 is not necessarily emitted with a constant irradiation energy set from the radiation source 12 due to a temperature rise of the radiation source 12 or the like. For example, if the difference value Sh is + ΔE, the radiation 16 having an irradiation energy higher by ΔE than the currently set irradiation energy is emitted from the radiation source 12. Therefore, the radiation source control unit 28 controls the radiation source 12 by resetting to the irradiation energy reduced by ΔE from the currently set irradiation energy. On the contrary, if the difference value Sh is −ΔE, the radiation source 12 emits radiation 16 having an irradiation energy higher than the currently set irradiation energy by ΔE. Then, the radiation source 12 is controlled by resetting the irradiation energy which is increased by ΔE to the currently set irradiation energy. As a result, the subject 16 is irradiated with the radiation 16 with substantially constant irradiation energy, and variations in light and shade are less likely to occur in the moving image displayed on the monitor 24.

  The operation of the third system control unit 20C in the moving image photographing processing unit 116 is because the third system control unit 20C and the radiation irradiation device 14 are electrically connected, and thus the first system control unit 20A and the second system. The operation is different from that of the moving image shooting processing unit 116 of the control unit 20B. That is, in accordance with an instruction from the third system control unit 20C, the radiation irradiation device 14 and the radiation detection device 18 are synchronized to perform moving image shooting.

  Here, the moving image shooting process in the third system control unit 20C will be described with reference to FIGS.

  First, in step S301 of FIG. 16, the third system control unit 20C stores an initial value (= 1) in the counter k of the number of photographing times.

  In step S <b> 302, the moving image parameter setting unit 120 determines whether or not new parameters (such as radiation 16 irradiation energy, readout mode, and imaging range) are set. For example, when the operator newly sets a parameter, the process proceeds to step S303, and the irradiation energy newly set in the moving image parameter history storage unit 122 is stored as the latest parameter.

  In step S <b> 304, first irradiation energy setting information Aa including information on the latest irradiation energy (information such as tube voltage, tube current, and irradiation time) is output to the radiation irradiation device 14. The radiation source control unit 28 of the radiation irradiation apparatus 14 sets the irradiation energy of the radiation 16 output from the radiation source 12 to a new irradiation energy based on the first irradiation energy setting information Aa from the moving image photographing processing unit 116. . Next, in step S305, the moving image readout control information including the newly set readout mode and imaging range is output to the corresponding radiation detection panel.

  In step S306, the third system control unit 20C determines whether or not a time corresponding to the latest frame rate Fr has elapsed since the start of the previous radiation imaging. When the value of the counter k is an initial value or when the time corresponding to the latest frame rate Fr has elapsed since the start of the previous radiation imaging, the process proceeds to the next step S307, and the third system control unit 20C An exposure start signal Si is output to the radiation irradiator 14 at the start of the radiation imaging. The radiation source control unit 28 of the radiation irradiation apparatus 14 controls the radiation source 12 based on the input of the exposure start signal Si from the third system control unit 20C, and the irradiation energy set from the radiation source 12 is controlled. Radiation 16 is irradiated.

  In step S308, the third system control unit 20C outputs the first operation start signal Sf1 and the second operation start signal Sf2 indicating charge accumulation and charge reading to the first radiation detection panel 32A and the second radiation detection panel 32B, respectively. To do.

  In step S309, the first radiation detection panel 32A and the second radiation detection panel 32B are configured to store charges based on the input of the first operation start signal Sf1 and the second operation start signal Sf2 from the third system control unit 20C, respectively. The charge is read out, and the first radiation image D1 and the second radiation image D2 for moving images are output. The first radiation image D1 from the first radiation detection panel 32A is supplied to the irradiation energy control unit 140, and the second radiation image D2 from the second radiation detection panel 32B is supplied to the moving image transfer unit 124 of the moving image capturing processing unit 116. Is done.

  In step S310, the irradiation energy control unit 140 calculates the above-described difference value Sh based on the supplied first radiation image D1 and supplies the calculated difference value Sh to the radiation irradiation apparatus 14. In step S311, the radiation source control unit 28 of the radiation irradiation apparatus 14 corrects the irradiation energy of the radiation 16 based on the supplied difference value Sh.

  In step S <b> 312, the moving image transfer unit 124 transfers the supplied second radiation image D <b> 2 for moving images to the console 22. The console 22 stores the transferred second radiation image D2 in the frame memory and displays it on the monitor 24 as a radiation image obtained by the k-th radiation imaging, that is, a k-th radiation image.

  In step S313, the value of the counter k is updated by +1.

  In step S314, the third system control unit 20C determines whether or not there is an end request for moving image shooting (for example, a still image shooting request or an energy sub moving image shooting request). If there is no end request for moving image shooting, the process returns to step S302, and the processes in and after step S302 are repeated. Thereby, a moving image of the radiation image at the set frame rate is displayed on the monitor 24. On the other hand, when it is determined in step S314 that there is a request to end moving image shooting, the moving image shooting ends.

  In the example of FIG. 17, the third system control unit 20 </ b> C starts exposure to the radiation irradiation device 14 at the start time tn−1 of the N−1th (N = 1, 2,...) Radiation imaging. By outputting the signal Si and outputting the first operation start signal Sf1 and the second operation start signal Sf2 to the first radiation detection panel 32A and the second radiation detection panel 32B, N−1 is supplied to the third system control unit 20C. Two radiographic images obtained by the second radiographing, that is, a first radiographic image D1 and a second radiographic image D2 are supplied. The irradiation energy control unit 140 of the third system control unit 20C calculates the above-described difference value Sh based on the supplied first radiation image D1, and supplies it to the radiation irradiation apparatus 14. The radiation source controller 28 of the radiation irradiation device 14 corrects the irradiation energy of the radiation 16 based on the supplied difference value Sh. In addition, the third system control unit 20C transfers the supplied second radiation image D2 to the console 22 and displays it on the monitor 24 as a radiation image of the (N-1) th frame.

  Similarly, the third system control unit 20C outputs an exposure start signal Si to the radiation irradiating apparatus 14 at the start time tn of the N-th radiography in which the latest frame rate Fr has elapsed from the above start time tn-1. Then, by outputting the first operation start signal Sf1 and the second operation start signal Sf2 to the first radiation detection panel 32A and the second radiation detection panel 32B, respectively, the third system control unit 20C receives the first radiation imaging by the Nth radiation imaging. A first radiation image D1 and a second radiation image D2 are supplied. The third system control unit 20 </ b> C supplies the radiation irradiation device 14 with a difference value Sh for correcting the irradiation energy of the radiation 16. In addition, the third system control unit 20C transfers the supplied second radiation image D2 to the console 22 and displays it on the monitor 24 as an Nth frame radiation image. By repeating these operations, radiation imaging is sequentially performed while correcting the irradiation energy of the radiation 16 to be constant, and a moving image of the radiation image is displayed on the monitor 24.

  By the way, the radiation detection apparatus 18 according to the present embodiment can perform still image shooting and energy sub shooting in addition to the above-described moving image shooting.

  First, as shown in FIG. 18, still image shooting is performed in a state where the second radiation detection panel 32 </ b> B is installed on the back side of the subject 36 and the first radiation detection panel 32 </ b> A is not installed on the front surface of the subject 36. Of course, the first radiation detection panel 32 </ b> A may be installed on the back side of the subject 36 and the second radiation detection panel 32 </ b> B may not be installed on the front side of the subject 36. This still image shooting is mainly executed by the still image shooting processing unit 142 (see FIG. 15). That is, the still image capturing processing unit 142 uses, for example, a still image capturing request input by an operator or a still image capturing request input from another device, for example, for still image capturing according to a capturing region. Set (higher energy than that for video) and control to execute radiography to obtain a still image.

  Specifically, as illustrated in FIG. 15, the still image shooting processing unit 142 includes a still image parameter setting unit 152, a still image parameter history storage unit 154, and a still image transfer unit 156. The still image parameter history storage unit 154 has the same configuration as the moving image parameter history storage unit 122 described above.

  Similar to the moving image parameter setting unit 120 described above, the still image parameter setting unit 152 newly sets parameters (radiation energy of the radiation 16, read mode, imaging range, etc.) by an operation input from an operator or the like. Etc.), the newly set irradiation energy, imaging range, etc. are stored in the still image parameter history storage unit 154 as the latest parameters. In particular, when the irradiation energy is newly set, the second irradiation energy setting information Ab including information on the newly set irradiation energy (information such as tube voltage, tube current, irradiation time, etc.) is sent to the radiation irradiation device 14. When the readout mode and imaging range are newly set, the still image readout control information Sb including the newly set readout mode and imaging range etc. is sent to the second radiation detection panel 32B of the radiation detection device 18. Output.

  The still image transfer unit 156 receives the second radiation image D2 supplied from the radiation detection device 18 (the second imaging unit 44B of the second radiation detection panel 32B and the second readout circuit 78B) and transfers it to the console 22. The console 22 displays the transferred second radiation image D2 on the monitor 24. As a result, a still image of the radiation image is displayed on the monitor 24.

  Here, still image shooting will be described with reference to FIGS. 19 and 20. First, in step S401 in FIG. 19, the still image parameter setting unit 152 determines whether or not there are new parameter settings (radiation 16 irradiation energy, readout mode, imaging range, and the like). For example, when the operator newly sets a parameter, the process proceeds to step S402, and the irradiation energy newly set in the still image parameter history storage unit 154 is stored as the latest parameter.

  In step S403, the second irradiation energy setting information Ab including the latest irradiation energy information (tube voltage, tube current, irradiation time, etc.) is output to the radiation irradiation apparatus 14. The radiation source control unit 28 of the radiation irradiation apparatus 14 sets the irradiation energy of the radiation 16 output from the radiation source 12 to a new irradiation energy based on the second irradiation energy setting information Ab from the still image capturing processing unit 142. To do.

  In step S404, the still image readout control information Sb including the latest readout mode and imaging range is output to the second radiation detection panel 32B of the radiation detection device 18. The second panel control unit 48B of the second radiation detection panel 32B supplies the input still image read control information Sb to the second address signal generation unit 110B.

  When it is determined in step S401 that no new parameter is set, or when the process in step S404 is completed, the process proceeds to the next step S405, and the still image shooting processing unit 142 operates the exposure switch. It is determined whether or not. When the exposure switch is operated, the process proceeds to step S406, and the third system control unit 20C outputs the exposure start signal Si to the radiation irradiation apparatus 14. The radiation source control unit 28 of the radiation irradiation apparatus 14 controls the radiation source 12 based on the input of the exposure start signal Si from the third system control unit 20C, and the irradiation energy set from the radiation source 12 is controlled. Radiation 16 is irradiated.

  In step S407, the still image capturing processing unit 142 outputs a second operation start signal Sf2 indicating charge accumulation and charge reading to the second radiation detection panel 32B of the radiation detection device 18.

  In step S <b> 408, the second radiation detection panel 32 </ b> B performs charge accumulation and charge readout based on the input of the second operation start signal Sf <b> 2 from the still image capturing processing unit 142, and generates a second radiation image D <b> 2 for still images. Output to the third system control unit 20C.

  In step S409, the still image transfer unit 156 of the still image capturing processing unit 142 transfers the supplied second radiographic image D2 for still images to the console 22. The console 22 stores the transferred second radiation image D2 in the frame memory and displays it on the monitor 24 as a still image.

  In step S410, the third system control unit 20C determines whether or not there is a still image shooting end request (for example, a moving image shooting request or an energy sub moving image shooting request). If there is no still image shooting end request, the process returns to step S401, and the processes in and after step S401 are repeated. On the other hand, in step S410, when it is determined that there is a request to end still image shooting, still image shooting ends.

  In the example of FIG. 20, the third system control unit 20 </ b> C outputs an exposure start signal Si to the radiation irradiation device 14 at the radiation imaging start time t <b> 0 to the second radiation detection panel 32 </ b> B of the radiation detection device 18. By outputting the operation start signal Sf2, the second radiation image D2 obtained by taking a still image is supplied to the third system control unit 20C. The third system control unit 20C transfers the supplied second radiation image D2 to the console 22 and displays it on the monitor 24 as a still image.

  Next, in the energy sub imaging, as shown in FIG. 21, a second radiation detection panel 32B is installed on the back side of the subject 36, and the first radiation detection panel is provided between the back side of the subject 36 and the second radiation detection panel 32B. 32A is installed, and further, an energy reduction filter 158 (for example, a copper plate, an aluminum plate, etc.) is installed between the first radiation detection panel 32A and the second radiation detection panel 32B. This energy sub photographing is mainly executed by the energy sub photographing processing unit 144 (see FIG. 15). That is, the energy sub imaging processing unit 144 sets the irradiation energy for subtraction imaging corresponding to the imaging region, for example, based on the operation input of the energy sub imaging request by the operator or the input of the energy sub imaging request from another device (moving image) Control to execute radiography to obtain an energy sub-image.

  Specifically, the energy sub imaging processing unit 144 includes an energy sub parameter setting unit 160, an energy sub parameter history storage unit 162, an energy sub image creation unit 164, and an energy sub image transfer unit 166. The energy sub parameter history storage unit 162 has the same configuration as the moving image parameter history storage unit 122 described above.

  Similar to the moving image parameter setting unit 120 described above, the energy sub parameter setting unit 160 newly sets parameters (irradiation energy of the radiation 16, readout mode, imaging range, etc.) upon operation input from the operator or the like. Is set, the newly set irradiation energy, frame rate, readout mode, imaging range, and the like are stored as the latest parameters in the energy sub parameter history storage unit 162.

  For example, when the irradiation energy is newly set, the third irradiation energy setting information Ac including information of the newly set irradiation energy (information such as tube voltage, tube current, irradiation time) is output to the radiation irradiation device 14. To do.

  When a readout mode, an imaging range, or the like for obtaining a first radiation image D1 by radiation of a low energy component is newly set, first energy sub readout control including newly set readout mode information, imaging range information, etc. The information Sc1 is output to the first radiation detection panel 32A. Similarly, when a readout mode, an imaging range, or the like is newly set in order to obtain a second radiation image D2 by radiation of a high energy component, a second energy sub including the newly set readout mode information, imaging range information, etc. The read control information Sc2 is output to the second radiation detection panel 32B.

  On the other hand, the energy sub-image creating unit 164 performs a weighted subtraction process between the first radiation image D1 output from the first radiation detection panel 32A and the second radiation image D2 output from the second radiation detection panel 32B, to thereby save energy. A radiographic image (energy sub-image Ds) for moving image shooting is created.

  The energy sub image transfer unit 166 transfers the created energy sub image Ds to the console 22. The console 22 displays the transferred energy sub-image Ds on the monitor 24.

  Here, the energy sub imaging will be described with reference to FIGS.

  First, in step S501 of FIG. 22, the energy sub parameter setting unit 160 determines whether or not there are new parameters (irradiation energy of the radiation 16, reading mode, imaging range, etc.). For example, when the operator newly sets a parameter, the process proceeds to step S502, and the irradiation energy, readout mode, imaging range, and the like newly set in the energy sub parameter history storage unit 162 are stored as the latest parameters.

  In step S503, third irradiation energy setting information Ac including information on the latest irradiation energy (information such as tube voltage, tube current, and irradiation time) is output to the radiation irradiation apparatus 14. The radiation source control unit 28 of the radiation irradiation apparatus 14 sets the irradiation energy output from the radiation source 12 to a new irradiation energy based on the third irradiation energy setting information Ac from the energy sub imaging processing unit 144. Next, in step S504, the energy sub read control information including the newly set read mode and imaging range is output to the corresponding radiation detection panel.

  When it is determined in step S501 that no new parameter is set, or when the processing in step S504 is completed, the process proceeds to the next step S505, where the energy sub imaging processing unit 144 determines whether the exposure switch has been operated. It is determined whether or not. When the exposure switch is operated, the process proceeds to step S506, and the third system control unit 20C outputs an exposure start signal Si to the radiation irradiation apparatus 14. The radiation source control unit 28 of the radiation irradiation apparatus 14 controls the radiation source 12 based on the input of the exposure start signal Si from the third system control unit 20C, and the irradiation energy set from the radiation source 12 is controlled. Radiation 16 is irradiated.

  In step S507, the energy sub imaging processing unit 144 outputs the first operation start signal Sf1 to the first radiation detection panel 32A of the radiation detection apparatus 18, and outputs the second operation start signal Sf2 to the second radiation detection panel 32B.

  In step S508, the first radiation detection panel 32A and the second radiation detection panel 32B perform charge accumulation and charge based on the input of the first operation start signal Sf1 and the second operation start signal Sf2 from the third system control unit 20C. Read. That is, of the radiation 16 that has passed through the subject 36, the radiation 16 having a low energy component is temporarily converted into visible light by the scintillator 58 of the first imaging unit 44A in the first radiation detection panel 32A, and each pixel of the first imaging unit 44A. At 80, visible light is photoelectrically converted to accumulate an amount of charge according to the amount of light. Similarly, the high-energy component radiation 16 is once converted into visible light by the scintillator 58 of the second imaging unit 44B in the second radiation detection panel 32B, and the visible light is photoelectrically converted in each pixel 80 of the second imaging unit 44B. Thus, an amount of electric charge corresponding to the amount of light is accumulated.

  In the subsequent readout period, the first address signal generator 110A creates an address signal according to the supplied first energy sub-read control information Sc1 (imaging range, readout mode, etc.), and performs line scanning in the first readout circuit 78A. The data is output to the address decoder 94 of the drive unit 90 and the address decoder 106 of the multiplexer 92. Similarly, the second address signal generator 110B creates an address signal corresponding to the supplied second energy sub-read control information Sc2 (imaging range, read mode, etc.), and a line scan driver in the second read circuit 78B. 90 address decoders 94 and multiplexer 92 output to address decoder 106.

  The first readout circuit 78A reads out charges according to the first energy sub-readout control information Sc1, and outputs the first radiation image D1 with low energy by using, for example, the FIFO method using the first image memory 112A. Similarly, the second readout circuit 78B reads out charges according to the second energy sub-readout control information Sc2, and outputs the second radiation image D2 with high energy by, for example, the FIFO method using the second image memory 112B. The first radiation image D1 and the second radiation image D2 are supplied to the third system control unit 20C.

  In step S509, the energy sub-image creating unit 164 compares the first radiation image D1 with low energy supplied from the first radiation detection panel 32A and the second radiation image D2 with high energy supplied from the second radiation detection panel 32B. An energy sub-image Ds is created by performing weighted subtraction.

  In step S <b> 510, the energy sub image transfer unit 166 transfers the created energy sub image Ds to the console 22. The console 22 stores the transferred energy sub-image Ds in the frame memory and displays it on the monitor 24.

  In the example of FIG. 23, at the radiation imaging start time t0, the third system control unit 20C outputs an exposure start signal Si to the radiation irradiation device 14, and the first radiation detection panel 32A and the second radiation detection panel. By outputting the operation start signals (Sf1, Sf2) to 32B, the first radiation image D1 with low energy and the second radiation image D2 with high energy are supplied to the third system control unit 20C. The third system control unit 20C performs a weighted subtraction process on the supplied first radiation image D1 and second radiation image D2 to create an energy sub-image Ds. Then, the created energy sub-image Ds is transferred to the console 22 and displayed on the monitor 24.

  As described above, in the radiographic image capturing system 10 having the irradiation energy control unit 140, two or more radiographing (moving image capturing) is performed in a certain period. For example, the irradiation energy varies due to a temperature rise of the radiation source 12 or the like. Even if it occurs, the irradiation energy can be corrected to be constant on the basis of the first radiation image D1, and variations in density and the like hardly occur in the moving image displayed on the monitor 24. That is, it is possible to obtain a moving image having the same shade as when the subject 36 is irradiated with a constant irradiation energy. In addition, in the first imaging unit 44A of the first radiation detection panel 32A, at least the soft line component of the radiation 16 from the radiation source 12 is absorbed. The subject is prevented from being exposed to the soft line component that does not contribute to the diagnosis, and the ineffective exposure to the subject 36 can be reduced.

  In addition, in the radiographic imaging system 10 having the third system control unit 20C, in addition to moving image capturing using the first radiation detection panel 32A and the second radiation detection panel 32B, the second radiation detection panel 32B (or the first radiation detection panel 32B). A still image photographing using the radiation detection panel 32A) and an energy sub photographing using the first radiation detection panel 32A and the second radiation detection panel 32B can be performed, and a versatile radiation image photographing system is provided. it can.

  Next, a system control unit (hereinafter, referred to as a fourth system control unit 20D) according to a fourth specific example will be described with reference to FIG.

  The fourth system control unit 20D has substantially the same configuration as the third system control unit 20C described above, but is different in that it further includes an irradiation field control unit 168. In FIG. 24, details of the moving image shooting processing unit 116, the still image shooting processing unit 142, and the energy sub shooting processing unit 144 are omitted.

  The irradiation field control unit 168 controls the irradiation range (including the irradiation position) of the radiation 16 emitted from the radiation source 12 based on at least the first radiation image D1 from the first imaging unit 44A.

  Specifically, the irradiation field control unit 168 includes an irradiation position specifying unit 170, an irradiation direction correction unit 172, and a collimator control unit 174.

  The irradiation position specifying unit 170 specifies the irradiation range of the radiation based on the gray value boundary of the first radiation image D1, stores the address information in the register 176, and further stores the center position (address information) of the irradiation range. ).

  The irradiation direction correction unit 172 reads the latest shooting range from the moving image parameter history storage unit 122 (see FIG. 15). Then, the center position of the shooting range is identified from the address information of the latest shooting range, and the center position of the shooting range and the center position of the irradiation range are determined based on the center position of the shooting range and the center position of the irradiation range described above. , That is, an irradiation position control signal Sk for correcting the pan angle and tilt angle of the radiation source 12 is output to the radiation irradiation device 14.

  The collimator control unit 174 is activated when there is an operation input from the operator (operation input indicating collimator driving) for the purpose of reducing the exposure burden on the subject 36 and the like, and is stored in the register 176. Based on the address information of the irradiation range and the address information of the set photographing range, a control signal for substantially matching the irradiation range and the photographing range, that is, the aperture amount of the automatic collimator unit 30 (see FIG. 2) is corrected. The irradiation range control signal Sm for performing is output to the radiation irradiation device 14.

  Thereby, based on the first radiation image D1, the center position of the imaging range of the subject 36 and the center position of the irradiation range of the radiation 16 can be substantially matched, and the irradiation range of the radiation 16 is appropriately set as the imaging range. Since it can be narrowed down, it is possible to reliably obtain a moving image of the shooting range and to effectively reduce the exposure burden on the subject 36.

  Next, a system control unit according to a fifth specific example (hereinafter referred to as a fifth system control unit 20E) will be described with reference to FIG.

  The fifth system control unit 20E has substantially the same configuration as the fourth system control unit 20D described above, but differs in that it includes the above-described amplifier gain control unit 130 instead of the irradiation energy control unit 140.

  Thereby, two or more radiation imaging (moving image imaging) is performed in a certain period, and even if the irradiation energy varies due to, for example, a temperature rise of the radiation source 12, the irradiation energy of the radiation 16 from the radiation source 12 is directly applied. Without the control, it is possible to reduce variations in light and shade in the moving image displayed on the monitor 24, and it is possible to obtain a moving image having the same light and shade as when the subject 36 is irradiated with a constant irradiation energy. .

  By the way, either one or both of the first radiation conversion panel 32A and the second radiation detection panel 32B described above may be flexible.

For example, the flexible first radiation detection panel 32A converts the fluorescence (visible light) in the visible light region emitted by the scintillator 58 into an electrical signal so that the TFT 84 and the pixel 80 can be formed by low-temperature film formation. An organic photoelectric conversion material (OPC) or an amorphous oxide semiconductor that converts fluorescence (for example, ultraviolet light) having an emission peak wavelength in a wavelength range from the purple region to the ultraviolet region emitted by the scintillator 58 into an electrical signal (for example, The pixel 80 is formed of IGZO (InGaZnOx)) or the like, while an organic semiconductor material (for example, phthalocyanine compound, pentacene or vanadyl phthalocyanine), an amorphous oxide semiconductor (for example, a-IGZO (InGaZnO ₄ )), or carbon What is necessary is just to comprise TFT84 from a nanotube. In this way, a plastic film that is transparent to at least reset light and has flexibility, such as a polyimide film, a polyarylate film, a biaxially stretched polystyrene film, an aramid film, or a bionanofiber. It can be employed as the base 60 of the sensor substrate.

  Here, the plastic film that can be used as the substrate 60 will be described more specifically. Polyesters such as polyethylene terephthalate, polybutylene phthalate, and polyethylene naphthalate, polystyrene, polycarbonate, polyethersulfone, polyarylate, polyimide, polycycloolefin, It is preferable to employ a flexible substrate such as norbornene resin or poly (chlorotrifluoroethylene) as the substrate 60. If such a plastic flexible substrate is used, the weight can be reduced, and for example, it is advantageous for carrying the radiation detection device 18 and the like.

  The base body 60 is provided with an insulating layer for ensuring insulation, a gas barrier layer for preventing permeation of moisture and oxygen, an undercoat layer for improving flatness or adhesion to electrodes, and the like. May be.

  When the aramid film is used to form the substrate 60, since a high temperature process of 200 ° C. or higher can be applied to the aramid, the transparent electrode material can be cured at a high temperature to reduce the resistance, and the solder reflow process It is also possible to support automatic mounting of driver ICs including Moreover, since aramid has a thermal expansion coefficient close to that of ITO (Indium Tin Oxide) or a glass substrate, warping after manufacturing is small and it is difficult to crack. Furthermore, aramid can form the base 60 thinner than a glass substrate or the like.

  In addition, the bionanofiber is a composite of a cellulose microfibril bundle (bacterial cellulose) produced by bacteria (acetobacterium Xylinum) and a transparent resin. In this case, the cellulose microfibril bundle has a width of 50 nm and a size of 1/10 of the wavelength of visible light, and has high strength, high elasticity, and low thermal expansion. By impregnating and curing a transparent resin such as an acrylic resin or an epoxy resin in bacterial cellulose, a bio-nanofiber having a light transmittance of about 90% at a wavelength of 500 nm can be obtained while containing 60% to 70% of the fiber. In addition, the bionanofiber has a low thermal expansion coefficient (3 ppm-7 ppm) comparable to that of a silicon crystal, is as strong as steel (460 MPa), has high elasticity (30 GPa), and is flexible. The substrate 60 can be formed thinner than the above.

  Then, when a flexible first radiation detection panel 32A is used as in the radiation detection apparatus (hereinafter referred to as the first radiation detection apparatus 18a) according to the first modification shown in FIG. A rigid second radiation detection panel 32B is installed on the back surface of 36, and a flexible first radiation detection panel 32A is installed on the front surface of the subject 36. In this case, a first box 178a in which an electronic circuit such as the first panel control unit 48A is accommodated is connected to the end of the first radiation detection panel 32A.

  According to the first radiation detection apparatus 18a, the first radiation detection panel 32A can be installed along the shape of the front surface of the subject 36, and the irradiation range of the radiation 16 on the subject 36 can be detected more accurately. Is possible. Thereby, for example, the correction accuracy of the pan angle and the tilt angle of the radiation source 12 by the irradiation field control unit 168 and the correction accuracy of the aperture amount of the automatic collimator unit 30 can be increased. Further, since the weight of the first radiation detection panel 32A can be reduced, when the first radiation detection panel 32A is placed on the subject 36 or held by the subject 36 or the operator, the subject 36 or the operator Can alleviate the burden. Further, unlike the rigid first radiation detection panel 32A, since the first radiation detection panel 32A is installed so as to wrap the front surface of the subject 36, the mechanical cold at the portion contacting the body is reduced, and the subject Tensions for 36 radiography can be relieved.

  When a flexible second radiation detection panel 32B is used as in the radiation detection apparatus (hereinafter referred to as second radiation detection apparatus 18b) according to the second modification shown in FIG. A flexible second radiation detection panel 32B is installed on the back surface, and a rigid first radiation detection panel 32A is installed on the front surface of the subject 36. In this case, a second box 178b in which an electronic circuit such as the second panel control unit 48B is accommodated is connected to the end of the second radiation detection panel 32B.

  According to the second radiation detection device 18b, the second radiation detection panel 32B can be installed along the shape of the back surface of the subject 36, so that the subject 36 can be photographed at the same magnification (moving image photographing, still image photographing). It becomes possible.

  Like the radiation detection apparatus according to the third modification shown in FIG. 28 (hereinafter referred to as the third radiation detection apparatus 18c), the first radiation detection panel 32A and the second radiation detection panel 32B having flexibility are used. If so, the flexible second radiation detection panel 32B is installed on the back surface of the subject 36, and the flexible first radiation detection panel 32A is installed on the front surface of the subject 36. In this case, the effect by the 1st radiation detection apparatus 18a mentioned above and the effect by the 2nd radiation detection apparatus 18b can be show | played.

  Like the radiation detection apparatus according to the fourth modification shown in FIG. 29 (hereinafter referred to as the fourth radiation detection apparatus 18d), the first radiation is applied to a part of one flexible long base 60. The first radiation detection panel 32A is provided as a first radiation detection panel region 180A by providing the constituent members of the detection panel 32A, and the second radiation detection panel region 180B is provided by providing other constituent members of the second radiation detection panel 32B. And the second radiation detection panel 32B may be integrated. Then, the flexible second radiation detection panel region 180B is positioned on the back surface of the subject 36, and the flexible first radiation detection panel region 180A is disposed on the front surface of the subject 36. In this case, a box 178 in which electronic circuits such as the first panel control unit 48A and the second panel control unit 48B are accommodated at the end of the first radiation detection panel region 180A or the end of the second radiation detection panel region 180B. Connected. In the example of FIG. 29, an example in which a box 178 is connected to the end of the first radiation detection panel region 180 is shown. Of course, the box 178 may be connected to the end of the second radiation detection panel region 180B, or the first box 178a (accommodated by the first panel control unit 48A, etc.) at the end of the first radiation detection panel region 180A. And a second box 178b (accommodated by the second panel control unit 48B, etc.) may be connected to the end of the second radiation detection panel region 180B.

  According to the fourth radiation detection device 18d, it is possible to achieve the effects of the first radiation detection device 18a and the second radiation detection device 18b described above. In addition, since the first radiation detection panel region 180A and the second radiation detection panel region 180B are provided on one flexible long base 60, the fourth is obtained by rounding the whole. Since the radiation detection device 18d itself can be accommodated in a narrow space, usability is improved.

  Of course, the radiation detection apparatus and the radiographic imaging system according to the present invention are not limited to the above-described embodiments, and various configurations can be adopted without departing from the gist of the present invention.

DESCRIPTION OF SYMBOLS 10 ... Radiation imaging system 12 ... Radiation source 14 ... Radiation irradiation apparatus 16 ... Radiation 18 ... Radiation detection apparatus 20 ... System control part 22 ... Console 24 ... Monitor 26 ... Input device 28 ... Radiation source control part 30 ... Automatic collimator part 32A ... first radiation detection panel 32B ... second radiation detection panel 36 ... subject 44A ... first imaging unit 44B ... second imaging unit 48A ... first panel control unit 48B ... second panel control unit 78A ... first readout circuit 78B ... Second readout circuit 80 ... Pixel 96 ... Charge amplifier 116 ... Moving picture imaging processing unit 118 ... Synchronization unit 130 ... Amplifier gain control unit 140 ... Irradiation energy control unit 142 ... Still image imaging processing unit 144 ... Energy sub imaging processing unit 158 ... Energy reduction Filter 168 ... Irradiation field control unit 180A ... First radiation detection panel region 180B ... Second release Ray detection panel area

Claims (18)

A first imaging unit that absorbs at least a part of a soft line component of radiation from a radiation source and detects at least the radiation;
A radiation detection apparatus comprising: a second imaging unit that converts at least the radiation from the radiation source that has passed through the subject into a radiation image and outputs the radiation image. The radiation detection apparatus according to claim 1,
The second imaging unit is more sensitive to a hard line component of the radiation than the first imaging unit. The radiation detection apparatus according to claim 2.
The first imaging unit absorbs the soft line component better than the hard line component,
The radiation detection apparatus, wherein the second imaging unit absorbs hard line components of the radiation better than the first imaging unit. The radiation detection apparatus according to any one of claims 1 to 3,
The radiation detection apparatus according to claim 1, wherein the first imaging unit is installed between the subject and a radiation source at least when capturing the moving image of the subject. The radiation detection apparatus according to any one of claims 1 to 3,
The radiation detection apparatus according to claim 1, wherein the first imaging unit is installed between the subject and the second imaging unit at least when photographing the still image of the subject. The radiation detection apparatus according to any one of claims 1 to 3,
The radiation detection apparatus, wherein the first imaging unit is not used at least for photographing a still image of the subject. The radiation detection apparatus according to any one of claims 1 to 3,
The radiation detection apparatus, wherein the first imaging unit is installed between the subject and the second imaging unit at least during energy subtraction imaging of the subject. The radiation detection apparatus according to claim 7.
A radiation detection apparatus, wherein an energy reduction filter is installed between the first imaging unit and the second imaging unit. In the radiation detection device according to any one of claims 1 to 8,
The first imaging unit is formed on a rigid first substrate,
The radiation detection apparatus, wherein the second imaging unit is formed on a rigid second substrate. In the radiation detection device according to any one of claims 1 to 8,
The first imaging unit is formed on a flexible substrate,
The radiation detection apparatus, wherein the second imaging unit is formed on a rigid substrate. In the radiation detection device according to any one of claims 1 to 8,
The first imaging unit is formed on a rigid substrate,
The radiation detection apparatus, wherein the second imaging unit is formed on a flexible substrate. In the radiation detection device according to any one of claims 1 to 8,
The first imaging unit is formed on a first flexible substrate,
The radiation detection apparatus, wherein the second imaging unit is formed on a second flexible substrate. In the radiation detection device according to any one of claims 1 to 8,
Having one flexible substrate,
The first imaging unit is formed on a part of the flexible substrate,
The radiation detection apparatus, wherein the second imaging unit is formed on another part of the flexible substrate. A radiation source;
A radiation detector;
In a radiographic imaging system having at least a control device for controlling the radiation detection device,
The radiation detection apparatus comprises:
A first imaging unit that absorbs at least a part of a soft line component of radiation from the radiation source and detects at least the radiation;
A radiographic imaging system comprising: the first imaging unit and a second imaging unit that converts the radiation from the radiation source that has passed through the subject into a radiographic image and outputs the radiographic image. The radiographic imaging system according to claim 14, wherein
The controller is
A radiographic imaging system comprising: a synchronization unit that sets a start timing of a charge accumulation period in the second imaging unit based on detection of radiation in the first imaging unit. The radiographic imaging system according to claim 14, wherein
The first imaging unit includes:
The control device controls the radiation source and the radiation detection device;
A radiographic imaging system comprising: an irradiation energy control unit that controls irradiation energy of the radiation source based on at least a detection signal from the first imaging unit. The radiographic imaging system according to claim 14, wherein
The control device controls the radiation source and the radiation detection device;
A radiographic imaging system comprising: an irradiation field control unit that controls an irradiation range of radiation emitted from the radiation source based on at least a detection signal from the first imaging unit. The radiographic imaging system according to claim 14, wherein
The controller is
A radiographic imaging system comprising an amplifier gain control unit that controls an amplifier gain in the second imaging unit based on at least a detection signal from the first imaging unit.

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