JP5398461B2 - Radiation image capturing apparatus, radiation image capturing system, method for controlling radiation image capturing apparatus, and control apparatus - Google Patents

Description

  The present invention relates to a radiographic imaging apparatus, a radiographic imaging system, a control method for a radiographic imaging apparatus, and a control apparatus.

  In recent years, radiation detectors such as flat panel detectors (FPDs) that can arrange radiation sensitive layers on TFT (Thin Film Transistor) active matrix substrates and convert radiation directly into digital data have been put into practical use. 2. Description of the Related Art A portable radiographic imaging device (hereinafter also referred to as “electronic cassette”) that generates image information indicating a radiographic image represented by radiation used and stores the generated image information has been put into practical use.

  This electronic cassette reads the electric charge generated in each pixel of the FPD as an electric signal, and converts the read electric signal into digital image data by an analog / digital (A / D) converter. The wiring to be transmitted easily picks up external noise, and the external noise is included in the image data.

  Therefore, Patent Document 1 describes the content of providing a photocoupler on the input side of the A / D converter and electrically insulating it from the A / D converter.

JP-A-11-308407

  By the way, some electronic cassettes are wired connection types that are used by connecting to a control terminal (so-called console) with a communication cable from the viewpoint of power supply or data transfer.

  In this wired connection type electronic cassette, various noises are transmitted via a communication cable, transmitted through the internal wiring of the device, and electric signal lines for charges (signal lines connecting each pixel to the A / D converter) and In some cases, the noise is included in the image data by multiplying the ground wiring (GND line) and the A / D converter.

  The technique described in Patent Document 1 removes noise generated in the wiring through which an electric signal flows from the FPD to the A / D converter. Therefore, even if the noise to the data signal after AD conversion can be removed, AD Noise before AD conversion including conversion time cannot be taken. That is, for example, when noise is placed on the GND line, the signal level of the electrical signal read from the FPD may fluctuate, resulting in a conversion error. Further, when noise is placed on the GND line and the GND of the AD converter is shaken by noise, an error occurs in the AD conversion value even if the electric signal read from the FPD is constant. In addition, even during the charge accumulation (during radiation irradiation) of each pixel of the FPD, if noise is placed on the GND line, the noise may be accumulated in the capacitor for storing the charge.

  The present invention has been made in view of the above-described facts, and controls a radiographic image capturing apparatus, a radiographic image capturing system, and a radiographic image capturing apparatus capable of suppressing noise transmitted via a cable from being included in image data. It is an object to provide a method and a control device.

In order to achieve the above object, a radiographic imaging apparatus according to claim 1 includes a radiation detector having a plurality of sensor units that accumulate charges generated by irradiation with radiation, and the radiation detector. A detection circuit that reads out the amount of charge accumulated in each sensor unit as an electrical signal, converts the read electrical signal into digital data and detects image information indicating a radiation image, and the detection circuit and the radiation detector means for storing electric power to be driven, is connected to the external device, connecting of the said transmission of the image information detected by the detection circuit to an external device, the power supply to the storage means,及beauty ground wire and at least one is carried out cables, power wires for energizing the electric power is accumulated into the accumulation means, and a cable that have at least one ground wire A switching unit that includes a relay switch or a switching element provided on at least one of the power wiring and the ground wiring, and switches the cable to an electrically separated state at least for a predetermined period during radiographic imaging. I have.

  According to the first aspect of the present invention, the amount of charge accumulated in each sensor unit of the radiation detector having a plurality of sensor units that accumulates the charges generated by the irradiation of the radiation by the detection circuit is respectively electric. Image information indicating a radiographic image is detected by converting the read electrical signal into digital data, and the power for driving the detection circuit and the radiation detector is accumulated by the storage means. Is connected to the external device, and at least one of transmission of image information detected by the detection circuit, supply of power to the storage means, and connection of ground wiring is performed by the switching means. At least during conversion to digital data by the detection circuit, the cable is electrically switched to the separated state.

  As described above, according to the first aspect of the present invention, since the cable is electrically switched to the separated state at least when the detection circuit converts the digital data, noise transmitted through the cable is included in the image data. Can be suppressed.

  In the first aspect of the invention, as in the second aspect of the invention, the predetermined period may be during irradiation of radiation to the radiation detector.

  In the invention described in claim 1, as in the invention described in claim 3, the predetermined period may be during conversion into digital data by the detection circuit.

The cable according to the present invention includes at least one of a power wiring that supplies power to be stored in the storage unit and the ground wiring, and the switching unit is provided on at least one of the power wiring and the ground wiring. Apply relay switch or switching element. Examples of the switching element include a transistor, a thyristor, and an SSR (Solid State Relay) (in the case of a power system).

According to the present invention, as in the invention described in claim 4 , the cable includes a signal wiring through which image information detected by the detection circuit is transmitted, and the switching unit is provided in the signal wiring. It is also possible to use a magnetic coupler or a photocoupler that converts an electric signal transmitted to the signal wiring into magnetism or light and converts the converted magnetism or light into an electric signal again.

Further, according to the present invention, as in the fifth aspect of the present invention, the ground wiring may be provided with a suppression unit that suppresses an inrush current generated at the start of energization of the relay switch or the switching element.

On the other hand, a radiographic imaging system according to a sixth aspect of the present invention is a radiation detector having a plurality of sensor units for accumulating charges generated by irradiation with radiation, and is accumulated in each sensor unit of the radiation detector. A detection circuit for reading out the respective charge amounts as electric signals, converting the read electric signals into digital data to detect image information indicating a radiation image, and accumulation for storing electric power for driving the detection circuit and the radiation detector A radiographic imaging device having a means, and a cable that performs at least one of transmission of image information detected by the detection circuit, supply of power to the storage means, and connection of a ground wiring, to the storage means The radiographic imaging device is connected via a cable having at least one of a power wiring and a ground wiring for energizing the stored power. And a control device that performs at least one of transmission of image information detected by the detection circuit, supply of power to the storage means, and connection of the ground wiring, and at least of the power wiring and the ground wiring Comprising a relay switch or a switching element provided on one side, and switching means for switching the radiographic imaging device and the control device to an electrically separated state at least for a predetermined period during radiographic imaging. Yes.

According to the sixth aspect of the present invention, since the radiographic image capturing apparatus and the control apparatus are electrically switched to the separated state at least during the conversion to digital data by the detection circuit, the noise transmitted through the cable is detected by the image data. Can be suppressed.

In the sixth aspect of the invention, the switching means may be provided in the control device as in the seventh aspect of the invention.

On the other hand, according to the control method of the radiographic imaging apparatus of the invention described in claim 8 , charges accumulated in each sensor unit of a radiation detector having a plurality of sensor units that accumulate charges generated by irradiation with radiation. It reads the amount as electric signals, respectively, and detects the image information indicating the ray image release converts the electrical signal by the detection circuit into digital data for a predetermined period during shooting of at least the radiation image, and the detection circuit An external device connected via a cable having at least one of a power wiring and a ground wiring for supplying the power to be stored in a storage means for storing the power for driving the radiation detector is connected to the power wiring and the ground wiring. Electrical separation is achieved by a relay switch or switching element provided in at least one of them.

According to the eighth aspect of the present invention, at least at the time of conversion into digital data by the detection circuit, it is electrically separated from the external device connected through the cable, so that noise transmitted through the cable is imaged. It is possible to suppress the data from appearing.

On the other hand, the radiation image capturing apparatus of the invention described in claim 9 is connected with the external device and the cable, the charges generated by the radiation is emitted into digital data, the drive power via the cable or In a radiation imaging apparatus that transmits and receives data including converted digital data, the cable supplies power to be stored in a detection circuit that detects image information indicating a radiation image and storage means that stores power for driving the radiation detector. Power wiring and at least one of ground wiring, comprising a relay switch or a switching element provided on at least one of the power wiring and ground wiring, at least for a predetermined period during radiographic imaging, Switching means for switching the cable to an electrically separated state is provided.

According to the ninth aspect of the present invention, since the cable is electrically switched to the separated state at least during the conversion of the electric charge into digital data, it is possible to suppress noise transmitted through the cable from appearing in the image data. be able to.

On the other hand, the control device of the invention described in claim 10 is connected to a radiographic imaging device that converts charges generated by irradiation of radiation into digital data, and transmits the converted digital data, the radiographic image A cable that performs at least one of supply of power to the imaging apparatus and connection of ground wiring, and stores in a detection circuit that detects image information indicating a radiation image and storage means that stores power for driving the radiation detector. And a relay switch or a switching element provided on at least one of the power wiring and the ground wiring, and at least a radiation image obtained by the radiation imaging apparatus. The cable is electrically disconnected for a predetermined period during the shooting. It comprises switching means for obtaining, a.

According to the invention described in claim 1 0, is switched to the electrically separated state the cable when converting to charge digital data by at least a radiographic imaging apparatus, the noise transmitted through the cable is image data Can be suppressed.

  According to the present invention, it is possible to suppress the noise transmitted through the cable from being included in the image data.

It is a block diagram which shows the structure of the radiation information system which concerns on embodiment. It is a figure which shows the mode of the radiation imaging room where the radiographic imaging system which concerns on embodiment was installed. It is a permeation | transmission perspective view which shows the internal structure of the electronic cassette concerning embodiment. It is a block diagram which shows the detailed structure of the radiographic imaging system which concerns on embodiment. It is the equivalent circuit diagram which paid its attention to 1 pixel part of the radiation detector which concerns on embodiment. It is a flowchart which shows the flow of a process of the insulation control processing program which concerns on embodiment. It is a schematic block diagram which shows the example which provided the relay switch and resistor which concern on other embodiment on the console side. It is a timing chart which shows the ON / OFF state of the relay switch which concerns on another form.

  The best mode for carrying out the present invention will be described below in detail with reference to the drawings.

  First, the configuration of the radiation information system 10 according to the embodiment will be described.

  In FIG. 1, the radiation information system 10 according to the present embodiment {hereinafter also referred to as “RIS10” (RIS: Radiology Information System). ) Is a block diagram showing each component.

  The RIS 10 is a system for managing information such as medical appointment reservations and diagnostic records in the radiology department, and constitutes a part of a hospital information system (HIS).

  The RIS 10 includes a plurality of imaging request terminal devices 12 (hereinafter also referred to as “terminal devices 12”), an RIS server 14, and a radiographic imaging system 18 installed in each radiation imaging room (or operating room) in a hospital. Are connected to a hospital network 16 composed of a wired or wireless LAN (Local Area Network). An HIS server (not shown) for managing the entire HIS is also connected to the in-hospital network 16.

  The terminal device 12 is used by doctors and radiographers to input and view diagnostic information and facility reservations, and radiographic image capturing requests (imaging reservations) are also made from the terminal device 12. Each terminal device 12 is composed of a personal computer with a display device, and is connected to the RIS server 14 by a hospital network 16 so that mutual communication is possible.

  The RIS server 14 receives an imaging request from each terminal device 12 and manages a radiographic imaging schedule in the imaging system 18 and includes a database 14A.

  The database 14A stores patient information such as patient attribute information (name, sex, date of birth, age, blood, patient ID, etc.), medical history, medical history, radiation images taken in the past, and electronic cassette 32 of the imaging system 18. Identification number, model, size, sensitivity, usable imaging part (contents of imaging request that can be supported), use start date, number of times of use, etc., information about electronic cassette 32, and radiographic image using electronic cassette 32 , That is, an environment in which the electronic cassette 32 is used (for example, an operating room or an imaging room installed exclusively for radiographic imaging) is included.

  The imaging system 18 captures a radiographic image by an operation of a doctor or a radiographer according to an instruction from the RIS server 14. The imaging system 18 absorbs the radiation X that has passed through the patient and the radiation generator 34 that irradiates the subject with radiation X having a dose according to the exposure conditions from the radiation source 130 (see FIGS. 2 and 3). An electronic cassette 32 including a radiation detector 60 (see FIG. 3) that generates charges and generates image information indicating a radiation image based on the generated charge amount, and a battery built in the electronic cassette 32 are charged. The cradle 40 includes an electronic cassette 32, a radiation generator 34, and a console 42 that controls the cradle 40.

  FIG. 2 shows an example of a state in which the imaging system 18 according to the present embodiment is arranged in the radiation imaging room 44.

  As shown in the figure, in the radiation imaging room 44, a rack 45 for holding the electronic cassette 32 when performing radiography in a standing position, and a patient lying down when performing radiography in a prone position. A bed 46 is installed, and the space in front of the rack 45 is used as a patient imaging position 48 when radiography is performed in a standing position, and the space above the bed 46 is used when radiography is performed in a prone position. The imaging position 50 of the patient is set.

  In the radiography room 44, the radiation source 130 is arranged around a horizontal axis (in FIG. 2) in order to enable radiography in a standing position and in a supine position by radiation from a single radiation source 130. A support moving mechanism 52 is provided that can be rotated in the direction of arrow A), movable in the vertical direction (direction of arrow B in FIG. 2), and movably supported in the horizontal direction (direction of arrow C in FIG. 2). Yes. The support moving mechanism 52 includes a drive source that rotates the radiation source 130 around a horizontal axis, a drive source that moves the radiation source 130 in the vertical direction, and a drive source that moves the radiation source 130 in the horizontal direction. (Both not shown).

  The cradle 40 is formed with a housing portion 40 </ b> A capable of housing the electronic cassette 32.

  The electronic cassette 32 is housed in the housing portion 40A of the cradle 40 during standby, and the built-in battery is charged. When a radiographic image is taken, the electronic cassette 32 is taken out from the cradle 40 by a radiographer, and the photographing posture is upright. For example, the position is moved / positioned to a position 49 held by the rack 45, and the position is moved / positioned to a position 51 on the bed 46 if the photographing posture is the saddle position.

  In the imaging system 18 according to the present embodiment, the radiation generator 34 and the console 42 and the electronic cassette 32 and the console 42 are connected by cables, and various types of information are transmitted and received by wired communication. The cables that connect the devices are omitted.

  The electronic cassette 32 is not limited to being used in the radiation imaging room 44, and can be applied to, for example, medical examinations and rounds in hospitals.

  FIG. 3 shows an internal configuration of the electronic cassette 32 according to the present exemplary embodiment.

  As shown in the figure, the electronic cassette 32 includes a housing 54 made of a material that transmits the radiation X, and has a waterproof and airtight structure. When the electronic cassette 32 is used in an operating room or the like, there is a risk that blood and other germs may adhere. Therefore, one electronic cassette 32 can be used repeatedly by sterilizing and cleaning the electronic cassette 32 as necessary with a waterproof and airtight structure. A connection terminal 32 </ b> A for connecting a communication cable is provided on a side surface of the housing 54.

  Inside the housing 54 are a grid 58 for removing scattered radiation of the radiation X by the patient from the irradiation surface 56 side of the housing 54 irradiated with the radiation X, and a radiation detector 60 for detecting the radiation X transmitted through the patient. And the lead plate 62 which absorbs the back scattered radiation of the radiation X is arrange | positioned in order. Note that the irradiation surface 56 of the housing 54 may be configured as a grid 58.

  In addition, a case 31 that houses an electronic circuit including a microcomputer and a rechargeable secondary battery is disposed at one end side inside the housing 54. The radiation detector 60 and the electronic circuit are operated by electric power supplied from the secondary battery disposed in the case 31. In order to avoid various circuits housed in the case 31 from being damaged by the radiation X irradiation, it is desirable to arrange a lead plate or the like on the irradiation surface 22 side of the case 31.

  FIG. 4 is a block diagram showing a detailed configuration of the radiation image capturing system 18 according to the present embodiment.

  The radiation generator 34 is provided with a connection terminal 34 </ b> A for communicating with the console 42. The console 42 is provided with a connection terminal 42 </ b> A for communicating with the radiation generator 34 and a connection terminal 42 </ b> B for communicating with the electronic cassette 32.

  The radiation generator 34 is connected to the console 42 via the communication cable 35. The electronic cassette 32 has a communication cable 43 connected to the connection terminal 32 </ b> A and is connected to the console 42 via the communication cable 43 when a radiographic image is taken.

  The radiation detector 60 built in the electronic cassette 32 is configured by laminating a photoelectric conversion layer that absorbs the radiation X and converts it into charges on a TFT active matrix substrate 66. The photoelectric conversion layer is made of amorphous a-Se (amorphous selenium) containing, for example, selenium as a main component (for example, a content rate of 50% or more), and when irradiated with radiation X, a charge corresponding to the amount of irradiated radiation. By generating a certain amount of charge (electron-hole pairs) internally, the irradiated radiation X is converted into a charge. The radiation detector 60 is indirectly charged using a phosphor material and a photoelectric conversion element (photodiode) instead of the radiation-charge conversion material that directly converts the radiation X such as amorphous selenium into an electric charge. May be converted to As phosphor materials, gadolinium sulfate (GOS) and cesium iodide (CsI) are well known. In this case, radiation X-light conversion is performed by a fluorescent material, and light-charge conversion is performed by a photodiode of a photoelectric conversion element.

  Further, on the TFT active matrix substrate 66, a pixel portion 74 (in FIG. 4) provided with a storage capacitor 68 for storing the charge generated in the photoelectric conversion layer and a TFT 70 for reading out the charge stored in the storage capacitor 68. A large number of photoelectric conversion layers corresponding to the individual pixel portions 74 are schematically shown as photoelectric conversion portions 72), and are arranged in a matrix. The electric charges generated in are accumulated in the storage capacitors 68 of the individual pixel portions 74. As a result, the image information carried on the radiation X irradiated to the electronic cassette 32 is converted into charge information and held in the radiation detector 60.

  Further, on the TFT active matrix substrate 66, a plurality of gate wirings 76 extending in a certain direction (row direction) for turning on / off the TFTs 70 of the individual pixel portions 74, and a direction (column direction) orthogonal to the gate wirings 76 are provided. A plurality of data wirings 78 are provided for reading out stored charges from the storage capacitor 68 through the TFT 70 which is extended and turned on. Individual gate lines 76 are connected to a gate line driver 80, and individual data lines 78 are connected to a signal processing unit 82. When charges are accumulated in the storage capacitors 68 of the individual pixel portions 74, the TFTs 70 of the individual pixel portions 74 are sequentially turned on in units of rows by a signal supplied from the gate line driver 80 via the gate wiring 76. The charge stored in the storage capacitor 68 of the pixel unit 74 for which is turned on is transmitted as an analog electrical signal through the data wiring 78 and input to the signal processing unit 82. Accordingly, the charges accumulated in the storage capacitors 68 of the individual pixel portions 74 are sequentially read out in units of rows.

  The signal processing unit 82 operates under the control of a cassette control unit 92, which will be described later, detects the amount of charge stored in the storage capacitor 68 of each pixel unit 74 in units of rows, and outputs digital image information.

  An image memory 90 is connected to the signal processing unit 82. Image information and error information output from the signal processing unit 82 are sequentially stored in the image memory 90. The image memory 90 has a storage capacity capable of storing a predetermined number of pieces of image information indicating a radiation image, and the read image information for one line is stored in the image memory each time the charge is read line by line. 90 are sequentially stored.

  The image memory 90 is connected to a cassette control unit 92 that controls the operation of the entire electronic cassette 32. The cassette control unit 92 is realized by a microcomputer, and includes a CPU 92A, a memory 92B including a ROM and a RAM, and a nonvolatile storage unit 92C including an HDD, a flash memory, and the like.

  A communication interface (I / F) 94 is connected to the cassette control unit 92. The communication I / F 94 is connected to the connection terminal 32A.

  In the electronic cassette 32 according to the present embodiment, a photocoupler 95 is provided for each wiring at a connection portion with the connection terminal 32A of the communication I / F 94. The photocoupler 95 incorporates a light emitting element and a light receiving element in a package that blocks light from the outside, converts an input electric signal into light by the light emitting element, and receives the light by the light receiving element to generate a signal. To communicate.

  The communication I / F 94 controls transmission of various information between the photocoupler 95 and an external device connected via the connection terminal 32A. The cassette control unit 92 can transmit and receive various types of information to and from an external device via the communication I / F 94. The cassette control unit 92 stores an exposure condition, which will be described later, received from the external device, and starts reading out charges based on the exposure condition.

  In addition, the electronic cassette 32 according to the present embodiment uses the housing 54 and the built-in substrate as a frame ground, and performs ground connection via the console 42 by using the communication cable 43 as a ground wiring. . In the electronic cassette 32 according to the present embodiment, the relay switch 97 and the resistor 98 are connected in series between the housing 54 used as a frame ground and the built-in board and the connection terminal 32A while insulating the periphery of the connection terminal 32A. It is possible to electrically insulate the ground wiring by the relay switch 97. The relay switch 97 is turned on / off in response to a switching instruction signal from the cassette control unit 92.

  In addition, the electronic cassette 32 is provided with a power supply unit 96, which functions as the above-described various circuits and elements (gate line driver 80, signal processing unit 82, image memory 90, communication I / F 94, and cassette control unit 92). The microcomputer is operated by the electric power supplied from the power supply unit 96. The power supply unit 96 incorporates a battery (a rechargeable secondary battery) so as not to impair the portability of the electronic cassette 32, and supplies power from the charged battery to various circuits and elements. In FIG. 4, the power supply unit 96 and wirings for connecting various circuits and elements are omitted.

  FIG. 5 shows an equivalent circuit diagram focusing on one pixel portion of the radiation detector 60 according to the present exemplary embodiment.

  As shown in the figure, the source of the TFT 70 is connected to a data line 78, and the data line 78 is connected to a signal processing unit 82. The drain of the TFT 70 is connected to the storage capacitor 68 and the photoelectric conversion unit 72, and the gate of the TFT 70 is connected to the gate wiring 76. The gate wiring 76 is connected to the gate line driver 80.

  The signal processing unit 82 includes a sample hold circuit 84 for each individual data wiring 78. The electric signal transmitted through each data wiring 78 is held in the sample hold circuit 84. The sample and hold circuit 84 includes an operational amplifier 84A and a capacitor 84B, and converts an electric signal into an analog voltage based on the frame ground voltage. The sample hold circuit 84 is provided with a switch 84C as a reset circuit that shorts both electrodes of the capacitor 84B and discharges the electric charge accumulated in the capacitor 84B.

  A multiplexer 86, a voltage amplifier 87, and an A / D converter 88 are sequentially connected to the output side of the sample hold circuit 84. The electric signals held in the individual sample and hold circuits are converted into analog voltages and sequentially input to the multiplexer 86 (serially). After the voltage is amplified by the voltage amplifier 87, a digital image is obtained by the A / D converter 88. Converted to information.

  On the other hand, the console 42 (see FIG. 4) is configured as a server computer, and includes a display 100 that displays an operation menu, a captured radiographic image, and the like, and a plurality of keys. And an operation panel 102 to which operation instructions are input.

  The console 42 according to the present embodiment includes a CPU 104 that controls the operation of the entire apparatus, a ROM 106 that stores various programs including a control program in advance, a RAM 108 that temporarily stores various data, and various data. HDD 110 that stores and holds, display driver 112 that controls display of various types of information on display 100, operation input detection unit 114 that detects an operation state of operation panel 102, and connection terminal 42A, and is connected to connection terminal 42A. And a communication I / F unit 116 that transmits and receives various types of information such as exposure conditions and posture information, and state information of the radiation generator 34, which will be described later, to and from the radiation generator 34 via the communication cable 35, and a connection terminal 42B Connected to the electronic cassette 32 via the connection terminal 42B and the communication cable 43. It includes a communication I / F 118 for transmitting and receiving various information such as various kinds of information such as elevation conditions and image information.

  The CPU 104, ROM 106, RAM 108, HDD 110, display driver 112, operation input detection unit 114, communication I / F unit 116, and communication I / F 118 are connected to each other via a system bus BUS. Therefore, the CPU 104 can access the ROM 106, RAM 108, and HDD 110, controls display of various information on the display 100 via the display driver 112, and the radiation generator 34 via the communication I / F unit 116. Control of transmission / reception of various information to / from the electronic cassette 32 and control of transmission / reception of various information to / from the electronic cassette 32 via the communication I / F 118 can be performed. Further, the CPU 104 can grasp the operation state of the user with respect to the operation panel 102 via the operation input detection unit 114.

  On the other hand, the radiation generator 34 communicates between the radiation source 130 that outputs the radiation X and the console 42, and transmits and receives various information such as exposure conditions, posture information, and state information of the radiation generator 34. 132, the radiation source controller 134 for controlling the radiation source 130 based on the received exposure conditions, and the operation of the support moving mechanism 52 by controlling the power supply to each drive source provided in the support moving mechanism 52. A radiation source drive control unit 136 for controlling

  The radiation source control unit 134 is also realized by a microcomputer, and stores the received exposure conditions and posture information. The exposure conditions received from the console 42 include information such as tube voltage, tube current, and irradiation period, and the posture information includes information indicating whether the photographing posture is standing or lying. If the imaging posture designated by the received posture information is in the standing position, the radiation source control unit 134 causes the radiation source 130 to be in the standing position imaging position 53A (see FIG. 2, exit) via the radiation source drive control unit 136. If the imaging posture specified by the received posture information is in the supine position, the support movement mechanism 52 is controlled so that the received radiation is positioned at a position at which the patient positioned at the imaging position 48 is irradiated from the side). The radiation source 130 is positioned at the position 53B for supine imaging (see FIG. 2, the position where the emitted radiation is irradiated from above to the patient positioned at the imaging position 50) via the radiation source drive control unit 136. Thus, the support moving mechanism 52 is controlled so that the radiation X is emitted from the radiation source 130 based on the received exposure conditions.

  Next, the operation of the imaging system 18 according to the present embodiment will be described.

  When capturing a radiographic image, the terminal device 12 (see FIG. 1) accepts an imaging request from a doctor or a radiographer. In the imaging request, the environment in which the electronic cassette 32 is used, the date and time of imaging, the region to be imaged, the imaging posture, the tube voltage, and the radiation dose to be irradiated are specified.

  The terminal device 12 notifies the RIS server 14 of the contents of the accepted imaging request. The RIS server 14 stores the contents of the imaging request notified from the terminal device 12 in the database 14A.

  The console 42 accesses the RIS server 14 to acquire the content of the imaging request from the RIS server 14 and displays the content of the imaging request on the display 100.

  In addition, the console 42 transmits posture information indicating an imaging posture in radiography to be performed from now on to the radiation generation device 34. As a result, the radiation source controller 134 of the radiation generator 34 controls the radiation source drive controller 136 so that the radiation source 130 is positioned at a position corresponding to the imaging posture specified by the received posture information.

  A doctor or a radiographer starts capturing a radiographic image based on the content of the imaging request displayed on the display 100.

  For example, as shown in FIG. 2, when taking a radiographic image of an affected part of a patient lying on the bed 46, a doctor or a radiologist can place a gap between the bed 46 and the affected part of the patient according to the part and angle of imaging. An electronic cassette 32 is disposed on the affected area, and a radiation generator 34 is disposed above the affected area. Further, the doctor or the radiographer designates an exposure condition for designating a tube voltage, a tube current, and an irradiation period when the operation panel 102 of the console 42 is irradiated with the radiation X according to the imaging region and imaging conditions of the patient Perform the operation.

  When an exposure condition designation operation is performed on the operation panel 102, the console 42 transmits the designated exposure condition to the radiation generator 34 and the electronic cassette 32. As a result, the radiation source control unit 134 prepares for exposure under the received exposure conditions.

  When the preparation for imaging of the radiation generator 34 is completed, the doctor or the radiographer performs an imaging instruction operation for instructing imaging on the operation panel 102 of the console 42. When an imaging instruction operation is performed on the operation panel 102, the console 42 transmits instruction information for instructing the start of exposure to the radiation generator 34 and the electronic cassette 32. Thereby, the radiation source 130 generates and emits radiation at a tube voltage, a tube current, and an irradiation period according to the exposure conditions received by the radiation generator 34 from the console 42.

  The radiation X emitted from the radiation source 130 reaches the electronic cassette 32 after passing through the patient. As a result, electric charges are accumulated in the accumulation capacitors 68 of the respective pixel portions 74 of the radiation detector 60 built in the electronic cassette 32.

  The cassette control unit 92 of the electronic cassette 32 controls the gate line driver 80 after the elapse of the irradiation period specified by the exposure condition after receiving the instruction information for instructing the start of exposure, and 1 line from the gate line driver 80. An ON signal is sequentially output to each gate wiring 76 one by one, and each TFT 70 connected to each gate wiring 76 is sequentially turned ON line by line.

  In the radiation detector 60, when the TFTs 70 connected to the gate lines 76 are turned on one line at a time, the charges accumulated in the storage capacitors 68 one line at a time flow out to the data lines 78 as electric signals. The electric signal flowing out to each data line 78 is inputted to each sample hold circuit 84 and converted into a voltage signal, and the converted voltage signal is inputted to the multiplexer in order (serially), and digitally inputted by the A / D converter 88. Is converted into the image information and stored in the image memory 90.

  Incidentally, noise is transmitted via the communication cable 43 when the gate line driver 80 outputs an ON signal to each gate line 76 in order line by line and reads out the charges accumulated in each storage capacitor 68 in order line by line. May be. Further, noise may be transmitted to the communication cable 43 used as the ground wiring, and noise may be generated in the frame ground.

  Therefore, in this embodiment, a photocoupler 95 is provided to prevent noise from being transmitted to the communication I / F 94.

  In the present embodiment, the cassette control unit 92 turns off the relay switch 97 when the signal processing unit 82 detects the amount of charge by reading out the charge from the radiation detector 60, so that the frame ground Is electrically insulated from the ground wiring.

  FIG. 6 shows a flowchart showing the flow of the insulation control processing program executed by the CPU 92A. The program is stored in advance in a predetermined area of the memory 92B (ROM), and is executed by the CPU 92A when instruction information for instructing the start of exposure is received from the console 42.

  In step S10 in the figure, a switching instruction signal for turning off the relay switch 97 is output.

  The relay switch 97 is turned off by this switching instruction signal, the communication cable 43 is electrically insulated, and the electronic cassette 32 is electrically separated from the ground wiring, so that noise is transmitted through the frame ground. Is prevented.

  In the next step S12, it is determined whether or not the reading of charges from the radiation detector 60 is completed. If the determination is affirmative, the process proceeds to step S14, and if the determination is negative, the process proceeds to step S10.

  In step S14, a switching instruction signal for turning on the relay switch 97 is output, and the process ends.

  The relay switch 97 is turned on by this switching instruction signal, and the frame ground is electrically connected to the ground wiring. When there is a potential difference at the start of the connected energization, spark-like noise (inrush current) is generated. For this reason, in this embodiment, a resistor 98 is provided to provide impedance. The resistor 98 is preferably about 100 KΩ to 100 MΩ. Moreover, you may provide the coil from which the impedance which can suppress the rush current which generate | occur | produces at the time of an energization start instead of the resistor 98 is obtained.

  Due to the processing of the insulation control processing program, the electronic cassette 32 is electrically separated from the ground wiring during reading of charges from the radiation detector 60, so that noise is prevented from being transmitted through the frame ground. Is done.

  The cassette control unit 92 transmits the image information stored in the image memory 90 to the console 42 by wireless communication after the end of photographing.

  The console 42 performs various types of image processing such as shading correction on the received image information, and stores the corrected image information in the HDD 110. The image information stored in the HDD 110 is displayed on the display 100 for confirmation of the captured radiographic image, and is also transferred to the RIS server 14 and stored in the RIS database. As a result, the captured radiographic image is displayed on the display of the terminal device 12, and the doctor can perform radiogram image interpretation, diagnosis, and the like.

  As described above, according to the present embodiment, the communication cable 43 is electrically switched from the electronic cassette 32 by the photocoupler 95 and the relay switch 97 to insulate noise transmitted through the communication cable 43. Therefore, it is possible to suppress the noise transmitted through the communication cable 43 from being included in the image data, and it is possible to suppress the deterioration of the image quality of the radiation image due to the transmitted noise.

  In the above embodiment, the case where the present invention is applied to an electronic cassette which is a portable radiographic imaging apparatus has been described. However, the present invention is not limited to this and is applied to a stationary radiographic imaging apparatus. May be.

  Moreover, although the case where the electronic cassette 32 and the console 42 were connected via the communication cable 43 was demonstrated in the said embodiment, this invention is not limited to this, The electronic cassette 32 is connected via a cable to others. You may make it connect with the apparatus of.

  Moreover, although the case where the communication cable 43 is switched from the electronic cassette 32 to the electrically separated state by the photocoupler 95 has been described in the above embodiment, the present invention is not limited to this. The communication cable 43 may be switched from the electronic cassette 32 to an electrically separated state. The magnetic coupler incorporates a coil and a magnetic sensor, converts an input electric signal into magnetism by the coil, and transmits the signal by detecting the magnetism by the magnetic sensor. Further, the communication cable 43 may be configured to be electrically switchable from the electronic cassette 32 using any element or mechanism.

  In the above-described embodiment, the case where the relay switch 97 is turned off at the timing when the instruction information instructing the start of exposure is received from the console 42 and the frame ground is electrically insulated from the ground wiring has been described. The invention is not limited to this. For example, the frame ground is electrically connected from the ground wiring at a timing closer to the time when the signal processing unit 82 converts the digital data, such as the timing immediately before the charge is read from the radiation detector 60. You may make it insulate.

  Furthermore, although the case where the ground wiring is insulated by the relay switch 97 has been described in the above-described embodiment, the present invention is not limited to this. For example, the electronic cassette 32 uses the communication cable 43 as the power wiring. When power is supplied via the communication cable 43, the power wiring may be insulated when the signal processing unit 82 converts the data into digital data. In this case, the electronic cassette 32 needs to store power necessary for radiographic image capturing by the power supply unit 96.

  In the above embodiment, the case where the relay switch 97, the resistor 98, and the photocoupler 95 are provided on the electronic cassette 32 side has been described. However, the present invention is not limited to this, and any one of them is provided on the cable. Or on the console 42 side.

  FIG. 7 shows an example in which a relay switch 97 and a resistor 98 are provided on the console 42 side.

  In the figure, the ground wiring 120 included in the communication cable 43 is branched into two, one wiring 120A is grounded via the relay switch 97A, and the other wiring 120B is grounded via the relay switch 97B and the resistor 98. Is grounded.

  A relay switch 97C is also provided in the signal wiring 122 for transmitting various information such as various information such as exposure conditions and image information included in the communication cable 43.

  FIG. 8 is a timing chart showing the ON / OFF states of the relay switches 97A to 97C when the signal processing unit 82 converts the digital data into digital data.

  As shown in the figure, at the time of conversion into digital data (AD conversion period) by the signal processing unit 82, the relay switches 97A to 97C are turned off, and the ground wiring 120 and the signal wiring 122 are switched to the electrically separated state.

  After the conversion to digital data by the signal processing unit 82, if there is a potential difference, spark-like noise is generated at the time of connection. Therefore, after the relay switch 97B is turned on and grounded via the resistor 98, the relay switch 98A Is turned on. Thereby, generation | occurrence | production of a spark-like noise is suppressed.

  In addition, the configuration of the radiation information system 10 described in the above embodiment (see FIG. 1), the configuration of the imaging system 18 (see FIGS. 2 and 4), and the configuration of the electronic cassette 32 (see FIG. 3) are examples. Needless to say, the present invention can be changed according to the situation without departing from the gist of the present invention.

  The process flow of the insulation control processing program described in the above embodiment (see FIG. 6) is also an example, and it goes without saying that it can be changed depending on the situation without departing from the gist of the present invention. .

32 Electronic cassette (radiographic imaging equipment)
42 Console (external equipment, control device)
43 Communication cable (cable)
60 Radiation detector 68 Storage capacity (sensor part)
72 Photoelectric conversion part (sensor part)
74 Pixel unit 82 Signal processing unit (detection circuit)
95 Photocoupler (switching means)
96 Power supply (storage means)
97 Relay switch (switching means)
98 Resistor (Suppression means)

Claims (10)

A radiation detector having a plurality of sensor units for accumulating charges generated by irradiation with radiation;
A detection circuit that reads out the amount of charge accumulated in each sensor unit of the radiation detector as an electrical signal, converts the read electrical signal into digital data, and detects image information indicating a radiation image; and
Storage means for storing power for driving the detection circuit and the radiation detector;
Is connected to an external device, the transmission of the image information detected by the detection circuit to the external device, the power supply to the storage means, and at least one of performing cable connection及beauty ground wire, a cable which have at least one of the power lines, and ground lines for energizing the electric power is accumulated into the accumulation means,
A switching unit that includes a relay switch or a switching element provided in at least one of the power wiring and the ground wiring, and switches the cable to an electrically separated state at least during a predetermined period during radiographic imaging;
A radiographic imaging apparatus comprising:   The radiographic image capturing apparatus according to claim 1, wherein the predetermined period is during irradiation of radiation to the radiation detector.   The radiographic image capturing apparatus according to claim 1, wherein the predetermined period is being converted into digital data by the detection circuit. The cable has a signal wiring through which image information detected by the detection circuit is transmitted,
The switching means is a magnetic coupler or a photocoupler that is provided in the signal wiring, converts an electric signal transmitted to the signal wiring into magnetism or light, and converts the converted magnetism or light into an electric signal again. The radiographic imaging apparatus of any one of Claims 1-3. The radiographic imaging device according to claim 1, wherein the ground wiring is provided with a suppression unit that suppresses an inrush current generated when energization of the relay switch or the switching element is started. A radiation detector having a plurality of sensor units for accumulating charges generated by irradiation with radiation, and reading out the amount of charge accumulated in each sensor unit of the radiation detector as an electrical signal, and digitally reading the read electrical signal A radiographic imaging apparatus having a detection circuit that converts image data to detect image information indicating a radiographic image, and an accumulation unit that accumulates electric power for driving the detection circuit and the radiation detector;
A cable that performs at least one of transmission of image information detected by the detection circuit, supply of power to the storage unit, and connection of a ground wiring, and a power line that supplies power to be stored in the storage unit; And at least one of transmission of image information detected by the detection circuit, supply of power to the storage means, and connection of the ground wiring. A control device that performs one;
It is composed of a relay switch or a switching element provided on at least one of the power wiring and the ground wiring, and the radiographic imaging apparatus and the control apparatus are electrically separated at least for a predetermined period during radiographic imaging. Switching means for switching to
Radiographic imaging system equipped with. The radiographic imaging system according to claim 6, wherein the switching unit is provided in the control device. The amount of charge accumulated in each sensor unit of a radiation detector having a plurality of sensor units that accumulates the charges generated by irradiation with radiation is read as an electrical signal, and the electrical signal is converted into digital data by a detection circuit. Then, image information indicating a radiographic image is detected, and at least during a predetermined period during radiographic image capturing, power to be stored is supplied to a storage unit that stores power for driving the detection circuit and the radiation detector. Radiation in which an external device connected via a cable having at least one of power wiring and ground wiring is electrically separated by a relay switch or switching element provided on at least one of the power wiring and ground wiring A method for controlling an image capturing apparatus. Are connected by external devices and the cable, radiation is charge generated by being irradiated is converted into digital data, the radiation imaging apparatus that performs transmission and reception of data including digital data driving power or transformed through the cable,
The cable has at least one of a detection circuit that detects image information indicating a radiation image, a power wiring that supplies power to be stored in a storage unit that stores power that drives the radiation detector, and a ground wiring.
It comprises a relay switch or a switching element provided in at least one of the power wiring and the ground wiring, and includes switching means for switching the cable to an electrically separated state at least for a predetermined period during radiographic imaging. Radiation imaging device. Connected to a radiographic imaging device that converts charges generated by irradiation of radiation into digital data, transmission of the converted digital data, supply of power to the radiographic imaging device, and connection of ground wiring A cable that performs at least one of at least one of a detection circuit that detects image information indicating a radiation image, a power wiring that supplies power to be stored in a storage unit that stores power for driving the radiation detector, and a ground wiring A cable having
It consists of a relay switch or a switching element provided on at least one of the power wiring and the ground wiring, and the cable is electrically separated at least for a predetermined period during radiographic image capturing by the radiographic image capturing apparatus. Switching means for switching;
A control device comprising:

Images