JP5634894B2 - Radiation imaging apparatus and program - Google Patents

Description

  The present invention relates to a radiographic image capturing apparatus and program, and more particularly, to a radiographic image capturing apparatus that captures a radiographic image indicated by radiation that has passed through a region to be imaged and a program executed by the radiographic image capturing apparatus.

  In recent years, radiation detectors such as FPD (Flat Panel Detector), which 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. A radiographic image capturing apparatus that captures a radiographic image represented by irradiated radiation has been put into practical use. The radiation detector used in this radiographic imaging apparatus has an indirect conversion system in which radiation is converted into light by a scintillator and then converted into electric charge in a semiconductor layer such as a photodiode, or the like. There is a direct conversion method in which a semiconductor layer such as amorphous selenium converts into electric charge, and there are various materials that can be used for the semiconductor layer in each method.

  By the way, in this type of radiographic imaging apparatus, the radiographic imaging apparatus, the radiation source, and the like are comprehensively controlled if the radiographic imaging apparatus itself can detect radiation start / stop, irradiation dose, and the like. Since it is not necessary to connect the imaging control device and the radiation source, it is preferable for simplifying the system configuration and simplifying the control by the imaging control device.

  As a technique related to a radiographic imaging apparatus that can detect the irradiation state of this type of radiation, Patent Document 1 discloses a radiation image detection unit that detects a radiation image of an object, and an amount of radiation from the object. A radiation imaging apparatus having a plurality of radiation dose detection units to be detected, and having a control unit that determines a mode of using the outputs of the plurality of radiation dose detection units based on an arrangement state of the radiation imaging apparatus. A radiation imaging apparatus is disclosed.

JP 2004-223157 A

  However, in the technique disclosed in Patent Document 1, since an amplifier is provided for each of the pixel for detecting a radiation image and the pixel for detecting a radiation dose, the detection of the radiation image and the radiation dose are performed. There is a problem that the power consumption increases when the detection is performed in parallel.

  Further, in the technique disclosed in Patent Document 1, switching noise caused by the switching TFT generated by the pixel for detecting the radiation dose and a leak current of dark current in the pixel are detected in the surrounding radiation image detection pixel. On the other hand, there is a problem that artifacts such as offset fluctuation and sensitivity fluctuation may occur due to superposition via stray capacitance and parasitic capacitance.

  The present invention has been made to solve the above-described problems, and an object of the present invention is to provide a radiographic imaging apparatus and program capable of preventing the occurrence of artifacts while suppressing power consumption.

In order to achieve the above object, the radiographic imaging device according to claim 1 is provided in a matrix form in a detection region for detecting radiation, and generates charges when irradiated with radiation or light converted from radiation. A plurality of pixels each having a sensor unit and a switching element for reading out the electric charge generated in the sensor unit, and the same configuration as each of the plurality of pixels, and the detection on the same substrate as the plurality of pixels A radiation detection element that is provided in the region and outputs an electrical signal corresponding to the electric charge generated in the sensor unit according to the radiation dose; and for each of the plurality of pixels, according to the switching state of the switch element a plurality of signal wires electrical signal corresponding to the charge generated in the sensor portion of the pixel flows are driven by the power supplied, electricity flows through the plurality of signal lines It has a first amplifier for amplifying No., respectively, based on the amplified electric signal in a first amplifier, directly not via generating means for generating image information, a switching element to the sensor portion of the radiation detection element At least one radiation detection wiring that is connected and through which an electrical signal output from the radiation detection element flows, and a second circuit that is driven by power supply and amplifies the electrical signal that flows through the radiation detection wiring A detection unit that includes an amplifier and detects a radiation irradiation state based on the electric signal amplified by the second amplifier; and one of a power supply period for the generation unit and a power supply period for the detection unit At least a portion of the detection period is different from that of the other period, and when the detection means detects that the irradiation of radiation has been completed, And a, and control means for controlling to stop the power supply to the.

  According to the radiographic imaging device of claim 1, the charge is generated by irradiating the sensor unit with the radiation or the light converted from the radiation by the plurality of pixels provided in a matrix in the detection region for detecting the radiation. The electric charge generated and generated in the sensor unit by the switch element is read out.

Further, in the present invention, the plurality of pixels are respectively the same configuration and, by the radiation detecting element provided in the detection region on the same substrate as the plurality of pixels, depending on the dose of the radiation sensor An electrical signal corresponding to the charge generated in the part is output.

In the present invention, each of the plurality of pixels includes a plurality of signal wirings through which an electrical signal corresponding to the electric charge generated in the sensor unit of the pixel according to the switching state of the switch element flows. Based on the electrical signal amplified by the first amplifier by the generation means having a first amplifier that is driven by power supply and that amplifies each of the electrical signals flowing through the plurality of signal wirings, the image information Is generated.

Furthermore, in the present invention, at least one radiation detection wiring that is directly connected to the sensor unit of the radiation detection element without a switch element and through which an electrical signal output from the radiation detection element flows is provided. The radiation state of radiation based on the electrical signal amplified by the second amplifier by the detection means that has the second amplifier that amplifies the electrical signal that is driven and supplied to the radiation detection wiring Is detected.

Here, in the present invention, the control means controls the power supply period for the generating means and the power supply period for the detection means so that at least a part of one period is different from the other period, and the detection means Is controlled so that the supply of power to the detection means is stopped when it is detected that the irradiation of radiation has ended .

As described above, according to the radiographic imaging device of claim 1, the first amplifier is provided, the power supply period for the generation unit that generates the image information, the second amplifier, and radiation irradiation. Control is performed so that at least a part of one period of the power supply period to the detection means for detecting the state is different from the other period, and detection is made when the detection means detects that the irradiation of radiation has been completed. Since the power supply to the means is controlled to be stopped , the generation of artifacts can be prevented while suppressing power consumption.

According to the present invention, as in the invention described in claim 2 , the control unit performs the control by stopping power supply to the generation unit during detection of the irradiation state of the radiation by the detection unit. May be. More this, it is possible to prevent more reliably the occurrence of artifacts.

The present invention, as in the invention according to claim 3, wherein the detection target irradiation state of said by the detectors radiation, the start of irradiation, the irradiation amount of radiological, and irradiation per unit time of radiation It may further include at least one of the dose rates. Thereby, the applied irradiation state can be detected while suppressing power consumption and preventing the occurrence of artifacts.

Further, according to the present invention, as in the invention described in claim 4 , the detection target of the irradiation state of the radiation by the detection unit includes reception start of radiation, and accepts input of imaging condition information indicating imaging conditions And a timing at which reception of the input of the imaging condition information by the reception unit is completed as a start timing of a power supply period for the detection unit. Thereby, power consumption can be suppressed more accurately.
The present invention further includes a switch that is operated to be pressed when the radiation is exposed, as in the invention described in claim 5, wherein the control unit is configured to detect the detection unit at a timing when the switch is pressed. The control unit may control the generation unit to generate power when the generation of the image information by the generation unit is completed, as in the invention described in claim 6. You may control to stop electric power supply.

On the other hand, in order to achieve the above object, the program according to claim 7 is provided in a matrix form in a detection region for detecting radiation, and generates charges when irradiated with radiation or light converted from radiation. A plurality of pixels provided with a sensor unit and a switching element for reading out the electric charge generated in the sensor unit, and the detection region on the same substrate as the plurality of pixels, having the same configuration as each of the plurality of pixels A radiation detection element that outputs an electrical signal corresponding to the charge generated in the sensor unit according to the radiation dose , and for each of the plurality of pixels, according to the switching state of the switch element, a plurality of signal lines electric signal flows corresponding to the charges generated in the sensor unit of the pixel is driven by the power supplied, an electrical signal flowing in the plurality of signal lines The has a first amplifier for amplifying respectively, based on the amplified electric signal in a first amplifier, and generating means for generating image information, directly connected without passing through the switching element to the sensor portion of the radiation detection element And at least one radiation detection wiring through which an electrical signal output from the radiation detection element flows, and a second amplifier that is driven by power supply and amplifies the electrical signal that flows through the radiation detection wiring And a detection unit that detects a radiation irradiation state based on the electric signal amplified by the second amplifier, and is a program executed by a radiographic image capturing apparatus. A receiving unit that receives an input of shooting condition information indicating a condition, and a timing at which reception of the input of the shooting condition information by the receiving unit ends. The timing of starting the power supply period for the means is controlled so that at least a part of one of the power supply period for the generation means and the power supply period for the detection means is different from the other period, and the detection means When it is detected that the irradiation of radiation has been completed, the control unit is configured to function as a control unit that controls to stop power supply to the detection unit.

Therefore, according to the seventh aspect of the invention, since the computer can be operated in the same manner as the radiographic image capturing apparatus according to the fourth aspect , the power consumption is suppressed as in the case of the radiographic image capturing apparatus. The generation of artifacts can be prevented.

According to the present invention, the power supply period for the generation unit that has the first amplifier and generates the image information, and the power supply period for the detection unit that has the second amplifier and detects the irradiation state of the radiation, And controlling so that at least a part of one period is different from that of the other period and stopping the power supply to the detection means when the detection means detects that the irradiation of radiation has ended. Therefore, it is possible to obtain an effect that the generation of artifacts can be prevented while suppressing power consumption.

It is a block diagram which shows the structure of the radiation information system which concerns on embodiment. It is a side view which shows an example of the arrangement | positioning state of each apparatus in the radiography room of the radiographic imaging system which concerns on embodiment. It is a cross-sectional schematic diagram which shows schematic structure of the 3 pixel part of the radiation detector which concerns on embodiment. It is the cross-sectional side view which showed schematically the structure of the signal output part of 1 pixel part of the radiation detector which concerns on embodiment. It is a top view which shows the structure of the radiation detector which concerns on embodiment. It is a top view which shows the arrangement | positioning state of the pixel for radiation detection which concerns on embodiment. It is a perspective view which shows the structure of the electronic cassette concerning embodiment. It is a section side view showing the composition of the electronic cassette concerning an embodiment. It is a block diagram which shows the principal part structure of the electrical system of the radiographic imaging system which concerns on embodiment. It is a circuit diagram which shows the structure of the image generation part which concerns on embodiment. It is a circuit diagram which shows the structure of the radiation irradiation detection part which concerns on embodiment. It is a flowchart which shows the flow of a process of the radiographic imaging processing program which concerns on embodiment. It is the schematic which shows an example of the initial stage information input screen which concerns on embodiment. It is a flowchart which shows the flow of a process of the cassette imaging | photography processing program which concerns on 1st Embodiment. It is a time chart (partial schematic diagram) which shows an example of the state transition of the principal part at the time of execution of the radiographic imaging process program and cassette imaging process program which concern on 1st Embodiment. It is a cross-sectional side view for demonstrating the surface reading system and back surface scanning system of a radiographic image. It is a flowchart which shows the flow of a process of the cassette imaging | photography processing program which concerns on 2nd Embodiment. It is a time chart (partial schematic diagram) showing an example of a state transition of a main part at the time of execution of the radiographic image capturing processing program and the cassette imaging processing program according to the second embodiment.

  DESCRIPTION OF EMBODIMENTS Hereinafter, embodiments for carrying out the present invention will be described in detail with reference to the drawings. Here, a description will be given of an example in which the present invention is applied to a radiation information system that is a system for comprehensively managing information handled in a radiology department in a hospital.

[First Embodiment]
First, the configuration of a radiation information system (hereinafter referred to as “RIS” (Radiology Information System)) 100 according to the present embodiment will be described with reference to FIG.

  The RIS 100 is a system for managing information such as medical appointments and diagnosis records in the radiology department, and constitutes a part of a hospital information system (hereinafter referred to as “HIS” (Hospital Information System)).

  The RIS 100 includes a plurality of radiography requesting terminal devices (hereinafter referred to as “terminal devices”) 140, a RIS server 150, and a radiographic imaging system (hereinafter referred to as a radiographic imaging room (or operating room) in a hospital). , Which are referred to as “imaging systems”) 104, which are connected to a hospital network 102 composed of a wired or wireless LAN (Local Area Network) or the like. The RIS 100 constitutes a part of the HIS provided in the same hospital, and an HIS server (not shown) for managing the entire HIS is also connected to the in-hospital network 102.

  The terminal device 140 is used by doctors and radiographers to input and browse diagnostic information and facility reservations, and radiographic image capturing requests and imaging reservations are also performed via the terminal device 140. Each terminal device 140 includes a personal computer having a display device, and can communicate with the RIS server 150 via the hospital network 102.

  On the other hand, the RIS server 150 receives an imaging request from each terminal device 140 and manages a radiographic imaging schedule in the imaging system 104, and includes a database 150A.

  Database 150A includes patient (subject) attribute information (name, sex, date of birth, age, blood type, weight, patient ID (Identification), etc.), medical history, medical history, radiation images taken in the past, etc. Information relating to the patient, information related to the electronic cassette 40 used in the imaging system 104, such as an identification number (ID information), model, size, sensitivity, start date of use, the number of times of use, etc., and the electronic cassette 40 It includes the environment information which shows the environment which takes a radiographic image using, ie, the environment (for example, a radiography room, an operating room, etc.) which uses electronic cassette 40.

  The imaging system 104 captures a radiographic image by an operation of a doctor or a radiographer according to an instruction from the RIS server 150. The imaging system 104 includes a radiation generator 120 that irradiates a subject with radiation X (see also FIG. 7) having a dose according to the exposure conditions from a radiation source 121 (see also FIG. 2), and a subject. Electrons that incorporate a radiation detector 20 (see also FIG. 7) that absorbs the radiation X that has passed through the subject's imaging target, generates charges, and generates image information indicating a radiation image based on the amount of generated charges. A cassette 40, a cradle 130 for charging a battery built in the electronic cassette 40, and a console 110 for controlling the electronic cassette 40 and the radiation generator 120 are provided.

  The console 110 acquires various types of information included in the database 150A from the RIS server 150 and stores them in an HDD 116 (see FIG. 9) described later, and uses the information as necessary to use the electronic cassette 40 and the radiation generator 120. Control.

  FIG. 2 shows an example of the arrangement state of each device in the radiation imaging room 180 of the imaging system 104 according to the present embodiment.

  As shown in the figure, the radiation imaging room 180 has a standing table 160 used when performing radiography in a standing position and a prone table 164 used when performing radiography in a lying position. The space in front of the standing stand 160 is set as a photographing position 170 of the subject when performing radiography in the standing position, and the space above the supine stand 164 is when performing radiography in the prone position. The imaging position 172 of the subject.

  The standing stand 160 is provided with a holding unit 162 that holds the electronic cassette 40, and the electronic cassette 40 is held by the holding unit 162 when a radiographic image is taken in the standing position. Similarly, the holding table 164 is provided with a holding unit 166 that holds the electronic cassette 40, and the electronic cassette 40 is held by the holding unit 166 when a radiographic image is taken in the lying position.

  Further, in the radiation imaging room 180, the radiation source 121 is placed around a horizontal axis (see FIG. 5) in order to enable radiation imaging in a standing position and radiation imaging in a lying position by radiation from a single radiation source 121. 2 is provided, and a support moving mechanism 124 is provided which can be rotated in the vertical direction (arrow b direction in FIG. 2) and can be moved in the horizontal direction (arrow c direction in FIG. 2). It has been. Here, the support moving mechanism 124 includes a drive source that rotates the radiation source 121 around a horizontal axis, a drive source that moves the radiation source 121 in the vertical direction, and a drive source that moves the radiation source 121 in the horizontal direction. Each is provided (not shown).

  On the other hand, the cradle 130 is formed with an accommodating portion 130 </ b> A capable of accommodating the electronic cassette 40.

  When the electronic cassette 40 is not used, the built-in battery is charged in a state of being housed in the housing portion 130A of the cradle 130. When a radiographic image is taken, the electronic cassette 40 is taken out from the cradle 130 by a radiographer or the like, and the photographing posture is established. If it is in the upright position, it is held in the holding part 162 of the standing base 160, and if it is in the upright position, it is held in the holding part 166 of the standing base 164.

  Here, in the imaging system 104 according to the present embodiment, various types of information are transmitted and received between the radiation generation apparatus 120 and the console 110 and between the electronic cassette 40 and the console 110 by wireless communication.

  The electronic cassette 40 is not used only in a state where it is held by the holding part 162 of the standing base 160 or the holding part 166 of the prone base 164. When photographing, it can be used in a state where it is not held by the holding unit.

  Next, the configuration of the radiation detector 20 according to the present embodiment will be described. FIG. 3 is a schematic cross-sectional view schematically showing the configuration of the three pixel portions of the radiation detector 20 according to the present exemplary embodiment.

  As shown in the figure, in the radiation detector 20 according to the present embodiment, a signal output unit 14, a sensor unit 13, and a scintillator 8 are sequentially stacked on an insulating substrate 1. The pixels are configured by the sensor unit 13. A plurality of pixels are arranged on the substrate 1, and the signal output unit 14 and the sensor unit 13 in each pixel are configured to overlap each other.

  The scintillator 8 is formed on the sensor unit 13 via the transparent insulating film 7, and forms a phosphor that emits light by converting radiation incident from above (opposite side of the substrate 1) or from below into light. It is a thing. Providing such a scintillator 8 absorbs the radiation transmitted through the subject and emits light.

  The wavelength range of light emitted by the scintillator 8 is preferably a visible light range (wavelength 360 nm to 830 nm), and in order to enable monochrome imaging by the radiation detector 20, the wavelength range of green is included. Is more preferable.

  Specifically, the phosphor used in the scintillator 8 is preferably one containing cesium iodide (CsI) when imaging using X-rays as radiation, and has an emission spectrum of 420 nm to 700 nm upon X-ray irradiation. It is particularly preferable to use CsI (Tl) (cesium iodide with thallium added). Note that the emission peak wavelength of CsI (Tl) in the visible light region is 565 nm.

  The sensor unit 13 includes an upper electrode 6, a lower electrode 2, and a photoelectric conversion film 4 disposed between the upper and lower electrodes. The photoelectric conversion film 4 absorbs light emitted from the scintillator 8 and generates charges. It is composed of an organic photoelectric conversion material.

Since it is necessary for the upper electrode 6 to cause the light generated by the scintillator 8 to be incident on the photoelectric conversion film 4, it is preferable that the upper electrode 6 be made of a conductive material that is transparent at least with respect to the emission wavelength of the scintillator 8. It is preferable to use a transparent conductive oxide (TCO) having a high transmittance for visible light and a small resistance value. Although a metal thin film such as Au can be used as the upper electrode 6, TCO is preferable because it tends to increase the resistance value when it is desired to obtain a transmittance of 90% or more. For example, ITO, IZO, AZO, FTO, SnO ₂ , TiO ₂ , ZnO _{2 and the} like can be preferably used, and ITO is most preferable from the viewpoint of process simplicity, low resistance, and transparency. Note that the upper electrode 6 may have a single configuration common to all pixels, or may be divided for each pixel.

  The photoelectric conversion film 4 includes an organic photoelectric conversion material, absorbs light emitted from the scintillator 8, and generates a charge corresponding to the absorbed light. In this way, the photoelectric conversion film 4 containing an organic photoelectric conversion material has a sharp absorption spectrum in the visible range, and electromagnetic waves other than light emitted by the scintillator 8 are hardly absorbed by the photoelectric conversion film 4. The noise generated by the radiation such as being absorbed by the photoelectric conversion film 4 can be effectively suppressed.

  The organic photoelectric conversion material constituting the photoelectric conversion film 4 is preferably such that its absorption peak wavelength is closer to the emission peak wavelength of the scintillator 8 in order to absorb light emitted by the scintillator 8 most efficiently. Ideally, the absorption peak wavelength of the organic photoelectric conversion material matches the emission peak wavelength of the scintillator 8, but if the difference between the two is small, the light emitted from the scintillator 8 can be sufficiently absorbed. . Specifically, the difference between the absorption peak wavelength of the organic photoelectric conversion material and the emission peak wavelength with respect to the radiation of the scintillator 8 is preferably within 10 nm, and more preferably within 5 nm.

  Examples of the organic photoelectric conversion material that can satisfy such conditions include quinacridone-based organic compounds and phthalocyanine-based organic compounds. For example, since the absorption peak wavelength of quinacridone in the visible region is 560 nm, if quinacridone is used as the organic photoelectric conversion material and CsI (Tl) is used as the material of the scintillator 8, the difference in the peak wavelength can be within 5 nm. Thus, the amount of charge generated in the photoelectric conversion film 4 can be substantially maximized.

  Next, the photoelectric conversion film 4 applicable to the radiation detector 20 according to the present embodiment will be specifically described.

  The electromagnetic wave absorption / photoelectric conversion site in the radiation detector 20 according to the present embodiment is configured by an organic layer including a pair of electrodes 2 and 6 and an organic photoelectric conversion film 4 sandwiched between the electrodes 2 and 6. be able to. More specifically, this organic layer is a part that absorbs electromagnetic waves, a photoelectric conversion part, an electron transport part, a hole transport part, an electron blocking part, a hole blocking part, a crystallization preventing part, an electrode, and an interlayer contact improvement. It can be formed by stacking or mixing parts.

  The organic layer preferably contains an organic p-type compound or an organic n-type compound.

  The organic p-type semiconductor (compound) is a donor organic semiconductor (compound) mainly represented by a hole-transporting organic compound and refers to an organic compound having a property of easily donating electrons. More specifically, an organic compound having a smaller ionization potential when two organic materials are used in contact with each other. Accordingly, any organic compound can be used as the donor organic compound as long as it is an electron-donating organic compound.

  An organic n-type semiconductor (compound) is an acceptor organic semiconductor (compound) mainly represented by an electron-transporting organic compound and refers to an organic compound having a property of easily accepting electrons. More specifically, the organic compound having the higher electron affinity when two organic compounds are used in contact with each other. Accordingly, as the acceptor organic compound, any organic compound can be used as long as it is an electron-accepting organic compound.

  The materials applicable as the organic p-type semiconductor and organic n-type semiconductor and the configuration of the photoelectric conversion film 4 are described in detail in Japanese Patent Application Laid-Open No. 2009-32854, and thus the description thereof is omitted. The photoelectric conversion film 4 may be formed by further containing fullerenes or carbon nanotubes.

  The thickness of the photoelectric conversion film 4 is preferably as large as possible in terms of absorbing light from the scintillator 8. However, when the thickness is more than a certain level, the photoelectric conversion film 4 is generated in the photoelectric conversion film 4 by a bias voltage applied from both ends of the photoelectric conversion film 4. Since electric field strength is reduced and charges cannot be collected, the thickness is preferably 30 nm to 300 nm, more preferably 50 nm to 250 nm, and particularly preferably 80 nm to 200 nm.

  In the radiation detector 20 shown in FIG. 3, the photoelectric conversion film 4 has a single configuration common to all pixels, but may be divided for each pixel.

  The lower electrode 2 is a thin film divided for each pixel. The lower electrode 2 can be made of a transparent or opaque conductive material, and aluminum, silver, or the like can be suitably used.

  The thickness of the lower electrode 2 can be, for example, 30 nm or more and 300 nm or less.

  In the sensor unit 13, by applying a predetermined bias voltage between the upper electrode 6 and the lower electrode 2, one of electric charges (holes, electrons) generated in the photoelectric conversion film 4 is moved to the upper electrode 6. The other can be moved to the lower electrode 2. In the radiation detector 20 of the present embodiment, a wiring is connected to the upper electrode 6, and a bias voltage is applied to the upper electrode 6 through this wiring. In addition, the polarity of the bias voltage is determined so that electrons generated in the photoelectric conversion film 4 move to the upper electrode 6 and holes move to the lower electrode 2, but this polarity is reversed. May be.

  The sensor unit 13 constituting each pixel only needs to include at least the lower electrode 2, the photoelectric conversion film 4, and the upper electrode 6. In order to suppress an increase in dark current, the electron blocking film 3 and the hole blocking film are used. 5 is preferably provided, and it is more preferable to provide both.

  The electron blocking film 3 can be provided between the lower electrode 2 and the photoelectric conversion film 4. When a bias voltage is applied between the lower electrode 2 and the upper electrode 6, electrons are transferred from the lower electrode 2 to the photoelectric conversion film 4. It is possible to suppress the dark current from increasing due to the injection of.

  An electron donating organic material can be used for the electron blocking film 3.

  The material actually used for the electron blocking film 3 may be selected according to the material of the adjacent electrode, the material of the adjacent photoelectric conversion film 4 and the like, and 1.3 eV or more from the work function (Wf) of the material of the adjacent electrode. Those having a large electron affinity (Ea) and an Ip equivalent to or smaller than the ionization potential (Ip) of the material of the adjacent photoelectric conversion film 4 are preferable. The material applicable as the electron donating organic material is described in detail in Japanese Patent Application Laid-Open No. 2009-32854, and thus the description thereof is omitted.

  The thickness of the electron blocking film 3 is preferably 10 nm or more and 200 nm or less, more preferably 30 nm or more and 150 nm or less, and particularly preferably, in order to surely exhibit the dark current suppressing effect and prevent a decrease in photoelectric conversion efficiency of the sensor unit 13. It is 50 nm or more and 100 nm or less.

  The hole blocking film 5 can be provided between the photoelectric conversion film 4 and the upper electrode 6. When a bias voltage is applied between the lower electrode 2 and the upper electrode 6, the hole blocking film 5 is transferred from the upper electrode 6 to the photoelectric conversion film 4. It is possible to suppress the increase in dark current due to the injection of holes.

  An electron-accepting organic material can be used for the hole blocking film 5.

  The thickness of the hole blocking film 5 is preferably 10 nm or more and 200 nm or less, more preferably 30 nm or more and 150 nm or less, and particularly preferably, in order to surely exhibit the dark current suppressing effect and prevent a decrease in photoelectric conversion efficiency of the sensor unit 13. Is from 50 nm to 100 nm.

  The material actually used for the hole blocking film 5 may be selected according to the material of the adjacent electrode, the material of the adjacent photoelectric conversion film 4 and the like, and 1.3 eV from the work function (Wf) of the material of the adjacent electrode. As described above, it is preferable that the ionization potential (Ip) is large and that the Ea is equal to or larger than the electron affinity (Ea) of the material of the adjacent photoelectric conversion film 4. Since the material applicable as the electron-accepting organic material is described in detail in Japanese Patent Application Laid-Open No. 2009-32854, description thereof is omitted.

  In addition, when a bias voltage is set so that holes move to the upper electrode 6 and electrons move to the lower electrode 2 among the charges generated in the photoelectric conversion film 4, the electron blocking film 3 and the hole blocking are set. The position of the film 5 may be reversed. Moreover, it is not necessary to provide both the electron blocking film 3 and the hole blocking film 5. If either one is provided, a certain degree of dark current suppressing effect can be obtained.

  A signal output unit 14 is formed on the surface of the substrate 1 below the lower electrode 2 of each pixel. FIG. 4 schematically shows the configuration of the signal output unit 14.

  As shown in the figure, the signal output unit 14 according to the present embodiment corresponds to the lower electrode 2, and a capacitor 9 that accumulates the charges transferred to the lower electrode 2, and the electric charges accumulated in the capacitor 9 are electrically A field effect thin film transistor (Thin Film Transistor, hereinafter simply referred to as a thin film transistor) 10 that converts the signal into a signal and outputs the signal is formed. The region in which the capacitor 9 and the thin film transistor 10 are formed has a portion that overlaps the lower electrode 2 in a plan view. With this configuration, the signal output unit 14 and the sensor unit 13 in each pixel are thick. There will be overlap in the vertical direction. In order to minimize the plane area of the radiation detector 20 (pixel), it is desirable that the region where the capacitor 9 and the thin film transistor 10 are formed is completely covered by the lower electrode 2.

  The capacitor 9 is electrically connected to the corresponding lower electrode 2 through a wiring made of a conductive material penetrating an insulating film 11 provided between the substrate 1 and the lower electrode 2. Thereby, the electric charge collected by the lower electrode 2 can be moved to the capacitor 9.

  In the thin film transistor 10, a gate electrode 15, a gate insulating film 16, and an active layer (channel layer) 17 are stacked, and a source electrode 18 and a drain electrode 19 are formed on the active layer 17 at a predetermined interval. .

  The active layer 17 can be formed of, for example, amorphous silicon, amorphous oxide, organic semiconductor material, carbon nanotube, or the like. In addition, the material which comprises the active layer 17 is not limited to these.

The amorphous oxide constituting the active layer 17 is preferably an oxide containing at least one of In, Ga, and Zn (for example, In—O-based), and at least two of In, Ga, and Zn. An oxide containing In (eg, In—Zn—O, In—Ga—O, or Ga—Zn—O) is more preferable, and an oxide containing In, Ga, and Zn is particularly preferable. As the In—Ga—Zn—O-based amorphous oxide, an amorphous oxide whose composition in a crystalline state is represented by InGaO ₃ (ZnO) _m (m is a natural number less than 6) is preferable, and InGaZnO is particularly preferable. ₄ is more preferable.

  Examples of the organic semiconductor material that can form the active layer 17 include, but are not limited to, phthalocyanine compounds, pentacene, vanadyl phthalocyanine, and the like. In addition, about the structure of a phthalocyanine compound, since it is demonstrated in detail in Unexamined-Japanese-Patent No. 2009-212389, description is abbreviate | omitted.

  If the active layer 17 of the thin film transistor 10 is formed of an amorphous oxide, an organic semiconductor material, or a carbon nanotube, it will not absorb radiation such as X-rays, or even if it absorbs it, it will remain in a very small amount. Generation of noise in the portion 14 can be effectively suppressed.

  When the active layer 17 is formed of carbon nanotubes, the switching speed of the thin film transistor 10 can be increased, and the thin film transistor 10 having a low light absorption in the visible light region can be formed. In addition, when the active layer 17 is formed of carbon nanotubes, the performance of the thin film transistor 10 is remarkably deteriorated only by mixing a very small amount of metallic impurities into the active layer 17, so that extremely high purity carbon nanotubes can be obtained by centrifugation or the like. It is necessary to form by separating and extracting.

  Here, any of the amorphous oxides, organic semiconductor materials, carbon nanotubes constituting the active layer 17 of the thin film transistor 10 and organic photoelectric conversion materials constituting the photoelectric conversion film 4 can be formed at a low temperature. . Therefore, the substrate 1 is not limited to a substrate having high heat resistance such as a semiconductor substrate, a quartz substrate, and a glass substrate, and a flexible substrate such as plastic, aramid, or bionanofiber can also be used. Specifically, flexible materials such as polyesters such as polyethylene terephthalate, polybutylene phthalate, polyethylene naphthalate, polystyrene, polycarbonate, polyethersulfone, polyarylate, polyimide, polycycloolefin, norbornene resin, poly (chlorotrifluoroethylene), etc. A conductive substrate can be used. If such a plastic flexible substrate is used, it is possible to reduce the weight, which is advantageous for carrying around, for example.

  In addition, the substrate 1 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.

  On the other hand, since aramid can be applied at a high temperature process of 200 ° C. or more, the transparent electrode material can be cured at a high temperature to reduce its resistance, and it can also be used for automatic mounting of a driver IC including a solder reflow process. Moreover, since aramid has a thermal expansion coefficient close to that of ITO (Indium Tin Oxide) or a glass substrate, there is little warping after manufacturing and it is difficult to crack. In addition, aramid can form a substrate thinner than a glass substrate or the like. The substrate may be formed by laminating an ultrathin glass substrate and aramid.

  The bionanofiber is a composite of a cellulose microfibril bundle (bacterial cellulose) produced by bacteria (Acetobacter Xylinum) and a transparent resin. The cellulose microfibril bundle has a width of 50 nm and a size of 1/10 of the visible light wavelength, 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. Bionanofiber has a low coefficient of thermal expansion (3-7ppm) comparable to silicon crystals, and is as strong as steel (460MPa), highly elastic (30GPa), and flexible, compared to glass substrates, etc. The substrate 1 can be formed thinly.

  In the present embodiment, the TFT substrate 30 is formed on the substrate 1 by sequentially forming the signal output unit 14, the sensor unit 13, and the transparent insulating film 7, and the light-absorbing adhesive resin is formed on the TFT substrate 30. The radiation detector 20 is formed by pasting the scintillator 8 using, for example.

  As shown in FIG. 5, the TFT substrate 30 includes a pixel 32 including the sensor unit 13, the capacitor 9, and the thin film transistor 10 described above in a certain direction (row direction in FIG. 5) and crossing the certain direction. A plurality of two-dimensional shapes are provided in the direction (column direction in FIG. 5).

  Further, the radiation detector 20 extends in the predetermined direction (row direction), and extends in the intersecting direction (column direction) with a plurality of gate wirings 34 for turning on and off each thin film transistor 10. A plurality of data wirings 36 for reading out charges through the thin film transistor 10 in the on state are provided.

  The radiation detector 20 has a flat plate shape and a quadrilateral shape having four sides on the outer edge in a plan view, more specifically, a rectangular shape.

  Here, in the radiation detector 20 according to the present exemplary embodiment, a part of the pixels 32 is used to detect the irradiation state of the radiation, and a radiographic image is captured by the remaining pixels 32. Hereinafter, the pixels 32 for detecting the radiation irradiation state are referred to as radiation detection pixels 32A, and the remaining pixels 32 are referred to as radiation image acquisition pixels 32B.

  In the radiation detector 20 according to the present embodiment, the radiation image is captured by the radiation image acquisition pixel 32B excluding the radiation detection pixel 32A in the pixel 32. Therefore, the radiation image at the position where the radiation detection pixel 32A is disposed. Pixel information cannot be obtained. For this reason, in the radiation detector 20 according to the present exemplary embodiment, the radiation detection pixels 32A are arranged so as to be dispersed, while the console 110 obtains the pixel information of the radiation image at the arrangement position of the radiation detection pixels 32A. A defective pixel correction process generated by interpolation using pixel information obtained by the radiation image acquisition pixel 32B positioned around the radiation detection pixel 32A is executed.

  Here, in the imaging system 104 according to the present embodiment, when imaging is performed using the entire imaging region by the radiation detector 20 as in the case where the imaging target region is an abdomen or the like, or the imaging target region is a leg part. In any case where imaging is performed using only a part of the imaging region by the radiation detector 20 as in the case of an arm portion, a hand portion, or the like, at least a region to be imaged in the central portion of the imaging region It is assumed that shooting is performed in a state where is positioned.

  On the other hand, in the radiation detector 20 according to the present exemplary embodiment, as schematically illustrated in FIG. 6 as an example, the radiation detection pixel 32A is arranged in an area near the center of the imaging region of the radiation detector 20 (hereinafter, “ 20A and 20B, and areas in the vicinity of the four corners of the peripheral part (hereinafter referred to as “peripheral part detection areas”) 20C to 20F.

  Then, in order to detect the irradiation state of radiation, the radiation detector 20 according to the present embodiment is connected to a connection portion between the capacitor 9 and the thin film transistor 10 in the radiation detection pixel 32A as shown in FIG. A direct readout wiring 38 for directly reading out the electric charge accumulated in the capacitor 9 is extended in the predetermined direction (row direction). In the radiation detector 20 according to the present embodiment, one direct readout wiring 38 is assigned to the plurality of radiation detection pixels 32A arranged in the predetermined direction, and the plurality of radiation detection pixels 32A. The connection portion between the capacitor 9 and the thin film transistor 10 is connected to a common (single) direct readout wiring 38.

  Next, the configuration of the electronic cassette 40 according to the present embodiment will be described. FIG. 7 is a perspective view showing the configuration of the electronic cassette 40 according to the present exemplary embodiment.

  As shown in the figure, an electronic cassette 40 according to the present embodiment includes a housing 41 made of a material that transmits radiation, and has a waterproof and airtight structure. When the electronic cassette 40 is used in an operating room or the like, there is a risk that blood or other germs may adhere. Therefore, one electronic cassette 40 can be used repeatedly by sterilizing and cleaning the electronic cassette 40 as necessary with a waterproof and hermetic structure.

  A space A for accommodating various components is formed inside the housing 41, and the radiation X transmitted through the subject from the irradiation surface side of the housing 41 to which the radiation X is irradiated is formed in the space A. The radiation detector 20 for detecting the radiation X and the lead plate 43 for absorbing the back scattered radiation of the radiation X are arranged in this order.

  Here, in the electronic cassette 40 according to the present exemplary embodiment, the area corresponding to the arrangement position of the radiation detector 20 on one flat surface of the housing 41 is a quadrilateral imaging area 41A capable of detecting radiation. Has been. The surface having the imaging region 41A of the casing 41 is a top plate 41B in the electronic cassette 40. In the electronic cassette 40 according to the present embodiment, the radiation detector 20 is connected to the TFT substrate 30 on the top plate 41B side. The top plate 41B is affixed to the inner surface of the casing 41 (the surface on the opposite side of the surface on which the radiation of the top plate 41B is incident).

  On the other hand, as shown in FIG. 7, a cassette control unit 58 and a power supply unit 70 (both described later) are placed on one end side inside the housing 41 so as not to overlap the radiation detector 20 (outside the range of the imaging region 41A). The case 42 which accommodates FIG. 9 is arrange | positioned.

  The casing 41 is made of, for example, carbon fiber (carbon fiber), aluminum, magnesium, bionanofiber (cellulose microfibril), or a composite material in order to reduce the weight of the entire electronic cassette 40.

  As the composite material, for example, a material including a reinforced fiber resin is used, and the reinforced fiber resin includes carbon, cellulose, and the like. Specifically, as the composite material, carbon fiber reinforced plastic (CFRP), a structure in which a foamed material is sandwiched with CFRP, or a material in which the surface of the foamed material is coated with CFRP is used. In the present embodiment, a structure in which a foam material is sandwiched with CFRP is used. Thereby, compared with the case where the housing | casing 41 is comprised with a carbon single-piece | unit, the intensity | strength (rigidity) of the housing | casing 41 can be improved.

  On the other hand, as shown in FIG. 8, a support body 44 is disposed on the inner surface of the back surface portion 41 </ b> C facing the top plate 41 </ b> B inside the housing 41, and radiation is provided between the support body 44 and the top plate 41 </ b> B. The detector 20 and the lead plate 43 are arranged in this order in the radiation X irradiation direction. The support body 44 is made of, for example, a foam material from the viewpoint of weight reduction and absorption of dimensional deviation, and supports the lead plate 43.

  As shown in the figure, an adhesive member 80 is provided on the inner surface of the top plate 41B to adhere the TFT substrate 30 of the radiation detector 20 in a peelable manner. As the adhesive member 80, for example, a double-sided tape is used. In this case, the double-sided tape is formed so that the adhesive force of one adhesive surface is stronger than the adhesive force of the other adhesive surface.

  Specifically, the weak adhesive surface (weakly adhesive surface) is set to 1.0 N / cm or less at 180 ° peel adhesive force. Then, the surface having a strong adhesive force (strong adhesion surface) is in contact with the top plate 41B, and the weak adhesion surface is in contact with the TFT substrate 30. Thereby, compared with the case where the radiation detector 20 is fixed to the top plate 41B with fixing members, such as a screw, the thickness of the electronic cassette 40 can be made thin. Even if the top plate 41B is deformed by an impact or load, the radiation detector 20 follows the deformation of the top plate 41B having high rigidity, so that only a large curvature (slow bend) is generated, and a local low curvature is generated. Therefore, the possibility that the radiation detector 20 is damaged is reduced. Furthermore, the radiation detector 20 contributes to the improvement of the rigidity of the top plate 41B.

  As described above, in the electronic cassette 40 according to the present exemplary embodiment, the radiation detector 20 is attached to the inside of the top plate 41B of the housing 41, so that the housing 41 is on the top plate 41B side and the back surface portion 41C side. When the radiation detector 20 is attached to the top plate 41B or the radiation detector 20 is peeled off from the top plate 41B, the housing 41 is placed on the top plate 41B side. And the back surface portion 41C side are separated into two.

  In the present embodiment, the radiation detector 20 may not be bonded to the top plate 41B in a clean room or the like. This is because when a foreign object such as a metal piece that absorbs radiation is mixed between the radiation detector 20 and the top plate 41B, the foreign object can be removed by peeling the radiation detector 20 from the top plate 41B.

  Next, with reference to FIG. 9, the main configuration of the electrical system of the imaging system 104 according to the present embodiment will be described.

  As shown in the figure, in the radiation detector 20 incorporated in the electronic cassette 40, a gate line driver 52 is arranged on one side of two adjacent sides, and an image generating unit 54 is arranged on the other side. Each gate wiring 34 of the TFT substrate 30 (in FIG. 9, individually expressed as gate wirings 34a, 34b,..., And this symbol is used as necessary) is connected to the gate line driver 52, and the TFT substrate. The 30 individual data wirings 36 are connected to the image generation unit 54.

  The housing 41 includes an image memory 56, a cassette control unit 58, and a wireless communication unit 60.

  Each thin film transistor 10 of the TFT substrate 30 is sequentially turned on in a row unit by a signal supplied from the gate line driver 52 via the gate wiring 34, and the electric charge read by the thin film transistor 10 in the on state is converted into an electric signal. The data wiring 36 is transmitted and input to the image generation unit 54. As a result, the charges are sequentially read out in units of rows, and a two-dimensional radiation image can be acquired.

  Here, the configuration of the image generation unit 54 according to the present embodiment will be described. FIG. 10 is a circuit diagram showing a configuration of the image generation unit 54 according to the present embodiment.

  As shown in the figure, the image generation unit 54 according to the present embodiment includes a variable gain preamplifier (charge amplifier) 82 and a sample hold circuit 84 corresponding to each of the data wirings 36. .

  The variable gain preamplifier 82 includes an operational amplifier 82A whose positive input side is grounded, a capacitor 82B connected in parallel between the negative input side and the output side of the operational amplifier 82A, and a reset switch 82C. The reset switch 82C is switched by the cassette control unit 58.

  The image generation unit 54 according to the present embodiment includes a multiplexer 86 and an A / D (analog / digital) converter 88. Note that the sample control of the sample hold circuit 84 and the selection output by the switch 86A provided in the multiplexer 86 are also switched by the cassette control unit 58.

  When detecting the radiation image, the cassette control unit 58 first discharges the charge accumulated in the capacitor 82B by turning on the reset switch 82C of the variable gain preamplifier 82 for a predetermined period.

  On the other hand, the charge accumulated in each capacitor 9 of the radiation image acquisition pixel 32B by irradiation with the radiation X is the data connected as an electrical signal when the connected thin film transistor 10 is turned on. The electrical signal transmitted through the wiring 36 and transmitted through the data wiring 36 is amplified by a corresponding variable gain preamplifier 82 at a predetermined amplification factor.

  On the other hand, the cassette control unit 58 holds the signal level of the electrical signal amplified by the variable gain preamplifier 82 in the sample hold circuit 84 by driving the sample hold circuit 84 for a predetermined period after performing the above-described discharge.

  The signal levels held in each sample hold circuit 84 are sequentially selected by the multiplexer 86 in accordance with the control by the cassette control unit 58 and are A / D converted by the A / D converter 88 to be photographed. Image data indicating a radiation image is generated.

  Note that the electronic cassette 40 according to the present exemplary embodiment is provided with an image generation unit power supply 54 </ b> A that supplies driving power to the image generation unit 54. The image generation unit power supply 54A according to the present embodiment is configured by a DC-DC converter whose power input end is connected to a power supply unit 70 described later, and the output end of the DC-DC converter is the image generation unit 54. Are connected to the variable gain preamplifier 82, the sample hold circuit 84, the multiplexer 86, and the A / D converter 88.

  Here, a cassette control unit 58 is connected to a control input terminal of the image generation unit power supply 54A according to the present embodiment, and power supply start and power supply stop from the image generation unit power supply 54A is performed by the cassette control unit 58. Be controlled.

  On the other hand, an image memory 56 is connected to the image generation unit 54, and image data output from the A / D converter 88 of the image generation unit 54 is sequentially stored in the image memory 56. The image memory 56 has a storage capacity capable of storing a predetermined number of image data, and image data obtained by imaging is sequentially stored in the image memory 56 each time a radiographic image is captured.

  The image memory 56 is connected to the cassette control unit 58. The cassette control unit 58 includes a microcomputer, and includes a CPU (Central Processing Unit) 58A, a memory 58B including a ROM (Read Only Memory) and a RAM (Random Access Memory), a nonvolatile storage unit 58C including a flash memory and the like. And controls the entire operation of the electronic cassette 40.

  Further, a wireless communication unit 60 is connected to the cassette control unit 58. The wireless communication unit 60 corresponds to a wireless local area network (LAN) standard represented by IEEE (Institute of Electrical and Electronics Engineers) 802.11a / b / g / n, etc. Control the transmission of various information between them. The cassette control unit 58 can wirelessly communicate with an external device such as the console 110 that performs control related to radiographic image capturing via the wireless communication unit 60, and can transmit and receive various types of information to and from the console 110 and the like. It is possible.

  In addition, the electronic cassette 40 is provided with a power supply unit 70, which functions as the above-described various circuits and elements (gate line driver 52, image generation unit 54, image memory 56, wireless communication unit 60, and cassette control unit 58). The microcomputer or the like) is operated by the power supplied from the power supply unit 70. The power supply unit 70 incorporates a battery (a rechargeable secondary battery) so as not to impair the portability of the electronic cassette 40, and supplies power from the charged battery to various circuits and elements. In FIG. 9, the power supply unit 70 and various circuits and wirings for connecting each element are omitted.

  On the other hand, in the radiation detector 20 according to the present embodiment, a radiation irradiation detection unit 55 is disposed on the opposite side of the gate line driver 52 across the TFT substrate 30 in order to detect the radiation irradiation state. Each direct readout wiring 38 of the substrate 30 (in FIG. 9, the direct readout wirings 38a, 38c,... Are individually indicated, and this symbol is used as necessary) is connected to the radiation irradiation detection unit 55. Yes.

  Here, the structure of the radiation irradiation detection part 55 which concerns on this Embodiment is demonstrated. FIG. 11 is a circuit diagram illustrating a configuration of the radiation irradiation detection unit 55 according to the present embodiment.

  As shown in the figure, the radiation irradiation detection unit 55 according to the present embodiment includes a variable gain preamplifier (charge amplifier) 92 corresponding to each of the direct readout wirings 38 connected to the radiation detection pixel 32A. It has been.

  The variable gain preamplifier 92 includes an operational amplifier 92A whose positive input side is grounded, a capacitor 92B connected in parallel between the negative input side and the output side of the operational amplifier 92A, and a reset switch 92C. The reset switch 92C is switched by the cassette control unit 58.

  Further, the radiation irradiation detection unit 55 according to the present embodiment is provided with an irradiation determination circuit 94 having an input terminal connected to each output terminal of the variable gain preamplifier 92 and an output terminal connected to the cassette control unit 58. Yes.

  When detecting the radiation irradiation state, the cassette control unit 58 first discharges the electric charge accumulated in the capacitor 92B by turning on the reset switch 92C of the variable gain preamplifier 92 for a predetermined period.

  On the other hand, the electric charge accumulated in each capacitor 9 of the radiation detection pixel 32A by being irradiated with the radiation X is transmitted through the direct readout wiring 38 connected as an electrical signal, and the electrical transmitted through the direct readout wiring 38 is transmitted. The signal is amplified by a corresponding variable gain preamplifier 92 at a predetermined amplification factor, and then input to the irradiation determination circuit 94.

  In the irradiation determination circuit 94 according to the present embodiment, the dose of radiation X irradiated from the radiation source 121 (hereinafter referred to as “radiation dose”) based on the electrical signal input from each of the variable gain preamplifiers 92. The first determination result information indicating the determination result is acquired by determining whether or not radiation irradiation has been started by determining whether or not the radiation dose has reached a predetermined first threshold value. Output to the cassette control unit 58.

  Further, in the irradiation determination circuit 94 according to the present embodiment, it is determined whether or not the irradiation of radiation has been completed by determining whether or not the radiation dose is less than a predetermined second threshold value. The second determination result information indicating the determination result is output to the cassette control unit 58.

  In the irradiation determination circuit 94 according to the present embodiment, when determining whether or not the radiation irradiation has started, the radiation detection pixels 32A (hereinafter referred to as “peripheral portions” in the peripheral detection regions 20C to 20F are determined. When the output signals from all the variable gain preamplifiers 92 corresponding to “pixels” include those whose radiation dose indicated by the output signals has reached the first threshold value, the radiation is used as the first determination result information. Control is performed so as to output information indicating that the irradiation is started.

  Further, in the irradiation determination circuit 94 according to the present embodiment, when determining whether or not the radiation irradiation has been completed, the radiation detection pixels 32A (hereinafter referred to as “center portion” in the center detection regions 20A and 20B). When the output signal from all the variable gain preamplifiers 92 corresponding to “pixels”) includes a radiation dose indicated by the output signal that is less than the second threshold value, the second determination result information Control is performed so as to output information indicating that radiation irradiation has ended.

  The electronic cassette 40 according to the present exemplary embodiment is provided with a radiation irradiation detection unit power supply 55 </ b> A that supplies driving power to the radiation irradiation detection unit 55. The radiation irradiation detection unit power supply 55 </ b> A according to the present embodiment is configured by a DC-DC converter whose power input end is connected to the power supply unit 70, and the output end of the DC-DC converter is the radiation irradiation detection unit 55. The variable gain preamplifier 92 and the irradiation determination circuit 94 are connected.

  Here, a cassette control unit 58 is connected to the control input terminal of the radiation irradiation detection unit power supply 55A according to the present embodiment, and the power supply start and stop of power supply from the radiation irradiation detection unit power supply 55A are controlled by the cassette control unit. 58.

  On the other hand, as shown in FIG. 9, the console 110 is configured as a server computer, and includes a display 111 that displays an operation menu, a captured radiographic image, and the like, and a plurality of keys. And an operation panel 112 for inputting operation instructions.

  The console 110 according to the present embodiment includes a CPU 113 that controls the operation of the entire apparatus, a ROM 114 that stores various programs including a control program in advance, a RAM 115 that temporarily stores various data, and various data. An HDD (Hard Disk Drive) 116 that stores and holds, a display driver 117 that controls display of various types of information on the display 111, and an operation input detection unit 118 that detects an operation state of the operation panel 112 are provided. . In addition, the console 110 transmits and receives various types of information such as an exposure condition, which will be described later, to and from the radiation generation apparatus 120 through wireless communication, and transmits and receives various types of information such as image data to and from the electronic cassette 40. A wireless communication unit 119 is provided.

  The CPU 113, ROM 114, RAM 115, HDD 116, display driver 117, operation input detection unit 118, and wireless communication unit 119 are connected to each other via the system bus BUS. Therefore, the CPU 113 can access the ROM 114, RAM 115, and HDD 116, controls the display of various information on the display 111 via the display driver 117, and the radiation generator 120 via the wireless communication unit 119 and Control of transmission and reception of various types of information with the electronic cassette 40 can be performed. Further, the CPU 113 can grasp the operation state of the user with respect to the operation panel 112 via the operation input detection unit 118.

  On the other hand, the radiation generator 120 includes a radio communication unit 123 that transmits and receives various types of information such as an exposure condition between the radiation source 121 and the console 110, and a line that controls the radiation source 121 based on the received exposure condition. A source control unit 122.

  The radiation source control unit 122 is also configured to include a microcomputer, and stores the received exposure conditions and the like. The exposure conditions received from the console 110 include information such as tube voltage and tube current. The radiation source control unit 122 causes the radiation source 121 to emit radiation X based on the received exposure conditions.

  Next, the operation of the imaging system 104 according to the present embodiment will be described.

  First, with reference to FIG. 12, the operation of the console 110 when radiographic images are taken will be described. FIG. 12 is a flowchart showing a flow of processing of a radiographic image capturing processing program executed by the CPU 113 of the console 110 when an instruction input for execution is performed via the operation panel 112. It is stored in advance in a predetermined area of the ROM 114.

  In step 300 in the figure, the display driver 117 is controlled so that a predetermined initial information input screen is displayed on the display 111, and in step 302, input of predetermined information is waited.

  FIG. 13 shows an example of an initial information input screen displayed on the display 111 by the processing in step 300 described above. As shown in the figure, in the initial information input screen according to the present embodiment, the name of the subject who will take a radiographic image, the part to be imaged, the posture at the time of radiography, and the exposure of the radiation X at the time of radiography A message for prompting input of conditions (in this embodiment, tube voltage, tube current, and exposure period when the radiation X is exposed) and an input area for these information are displayed.

  When the initial information input screen shown in the figure is displayed on the display 111, the photographer inputs the name of the subject to be imaged, the region to be imaged, the posture at the time of imaging, and the exposure conditions corresponding to each other. An area is input via the operation panel 112.

  When the posture at the time of imaging is the standing position or the lying position, the photographer holds the electronic cassette 40 in the holding section 162 of the corresponding standing table 160 or the holding section 166 of the lying table 164 and also the radiation source. After positioning 121 at the corresponding position, the subject is positioned at a predetermined imaging position. On the other hand, when a radiographic image is captured in a state where the imaging target part does not hold the electronic cassette 40 such as an arm part or a leg part on the holding part, the photographer covers the imaging target part in a state where the imaging target part can be imaged. The examiner, the electronic cassette 40, and the radiation source 121 are positioned. Thereafter, the photographer designates an end button displayed near the lower end of the initial information input screen via the operation panel 112. When an end button is designated by the photographer, step 302 is affirmative and the process proceeds to step 304.

  In step 304, information input on the initial information input screen (hereinafter referred to as “initial information”) is transmitted to the electronic cassette 40 via the wireless communication unit 119, and in the next step 306, the initial information is input. The exposure condition is set by transmitting the exposure condition included in the data to the radiation generator 120 via the wireless communication unit 119. In response to this, the radiation source control unit 122 of the radiation generator 120 prepares for exposure under the received exposure conditions.

  In the next step 308, instruction information for instructing the start of exposure is transmitted to the radiation generation apparatus 120 via the wireless communication unit 119.

  In response to this, the radiation source 121 starts emission of radiation X in the tube voltage, tube current, and exposure period according to the exposure conditions received by the radiation generator 120 from the console 110. The radiation X emitted from the radiation source 121 reaches the electronic cassette 40 after passing through the subject.

  On the other hand, when receiving the initial information, the cassette control unit 58 of the electronic cassette 40 waits until the first determination result information output from the irradiation determination circuit 94 becomes information indicating that radiation irradiation has started. The radiographic image capturing operation is started later. Next, the electronic cassette 40 waits until the second determination result information output from the irradiation determination circuit 94 becomes information indicating that radiation irradiation has ended, and then ends the imaging operation.

  Then, when the radiographic image capturing operation is completed, the electronic cassette 40 transmits image data obtained by the capturing to the console 110.

  Therefore, in the next step 310, the process waits until the image data is received from the electronic cassette 40. In the next step 312, the received image data is subjected to the above-described defective pixel correction process, and then the shading correction is performed. The image processing for performing various corrections such as the above is executed.

  In the next step 314, the image data subjected to the image processing (hereinafter referred to as “corrected image data”) is stored in the HDD 116, and in the next step 316, the radiation image indicated by the corrected image data is confirmed. The display driver 117 is controlled to display on the display 111 in order to perform the above.

  In the next step 318, the corrected image data is transmitted to the RIS server 150 via the in-hospital network 102, and then the radiographic imaging program is terminated. Note that the corrected image data transmitted to the RIS server 150 is stored in the database 150A, so that the doctor can perform interpretation, diagnosis, and the like of the radiographic image taken.

  Next, the operation of the electronic cassette 40 when the initial information is received from the console 110 will be described with reference to FIG. FIG. 14 is a flowchart showing a process flow of a cassette photographing process program executed by the CPU 58A in the cassette control unit 58 of the electronic cassette 40 at this time. The program is stored in a predetermined area of the memory 58B in advance. Yes.

  In step 400 of the figure, after controlling the image generation unit power 54A to start supplying power from the image generation unit power 54A to the image generation unit 54, in the next step 402, from the radiation irradiation detection unit power 55A. The radiation irradiation detection unit power supply 55A is controlled so as to start the power supply to the radiation irradiation detection unit 55, and in the next step 403, the gate line driver 52 is controlled and each gate wiring 34a, 34b is controlled from the gate line driver 52. , 34c,..., 34c,... Are sequentially output one line at a time, and the charge accumulated in the capacitor 9 in each pixel 32 of the radiation detector 20 is discharged. Each pixel 32 of 32B is reset. Note that the reset operation of each pixel 32 performed by the processing in step 403 may be performed only once or may be repeated a plurality of times.

  In the next step 404, the above-described first determination result information is acquired from the irradiation determination circuit 94, and in the next step 406, the acquired first determination result information indicates that radiation irradiation has started. If it is determined whether or not there is a negative determination, the process returns to step 404. On the other hand, if the determination is affirmative, the process proceeds to step 408.

  In step 408, the radiographic image capturing operation is started by starting the accumulation of electric charges in the capacitor 9 in each pixel 32 of the radiation detector 20.

  In the next step 410, the above-described second determination result information is acquired from the irradiation determination circuit 94, and in the next step 412, the acquired second determination result information indicates that radiation irradiation has been completed. If it is determined whether or not there is a negative determination, the process returns to step 410, while the process proceeds to step 414 when an affirmative determination is made.

  In step 414, the radiation irradiation detection unit power supply 55 </ b> A is controlled so as to stop the power supply from the radiation irradiation detection unit power supply 55 </ b> A started by the processing in step 402 to the radiation irradiation detection unit 55. The photographing operation started by the process 408 is terminated.

  In the next step 418, the gate line driver 52 is controlled so that the gate line driver 52 outputs an ON signal to each of the gate lines 34a, 34b, 34c,. Each thin film transistor 10 is sequentially turned on line by line.

  In the radiation detector 20, when the thin film transistors 10 connected to the gate lines 34 are turned on line by line, the charges accumulated in the capacitors 9 line by line flow out to the data lines 36 as electric signals. The electric signal flowing out to each data wiring 36 is converted into digital image data by the image generation unit 54 and stored in the image memory 56.

  Therefore, in this step 418, the image data stored in the image memory 56 is read out, and in the next step 420, the readout of the charge by the processing of step 418 of the capacitor 9 in each pixel 32 of the radiation detector 20 is completed. The image generation unit started by the process of step 400 after resetting each pixel 32 of the radiation detection pixel 32A and the radiation image acquisition pixel 32B by discharging the subsequent residual charge or the charge in which the dark current is accumulated. After the image generation unit power supply 54A is controlled to stop the power supply from the power supply 54A to the image generation unit 54, and in the next step 422, the read image data is transmitted to the console 110 via the wireless communication unit 60. The cassette imaging process program is terminated.

  FIG. 15 schematically shows an example of the state transition of the main part during execution of the radiographic image capturing processing program and the cassette imaging processing program according to the present embodiment.

  As shown in the figure, when the electronic cassette 40 receives the initial information from the console 110, the electronic cassette 40 starts supplying power to the image generation unit 54 and the radiation irradiation detection unit 55.

  Then, after resetting each pixel 32 of the radiation detection pixel 32 </ b> A and the radiation image acquisition pixel 32 </ b> B, it is output from each of the variable gain preamplifiers 92 provided in the radiation irradiation detection unit 55 as the radiation is irradiated. The signal level of the electrical signal is increased, and at least one of the radiation doses indicated by the signal level reaches the first threshold value. 1 judgment result information is output.

  When the first determination result information is output, the electronic cassette 40 starts accumulating charges according to the radiation dose by the capacitor 9 of the radiation image acquisition pixel 32B by starting the radiographic image capturing operation.

  After that, at least one of the radiation doses indicated by the electric signals output from each of the variable gain preamplifiers 92 provided in the radiation irradiation detection unit 55 as the radiation is continuously irradiated is less than the second threshold value. At that time, the irradiation determination circuit 94 outputs second determination result information indicating that the irradiation of radiation has ended.

  When the second determination result information is output, the electronic cassette 40 stops the power supply from the radiation irradiation detection unit power supply 55 </ b> A to the radiation irradiation detection unit 55.

  Thereafter, in the electronic cassette 40, image data indicating a radiographic image obtained by imaging is stored in the image memory 56 by reading an electrical signal from the radiographic image acquisition pixel 32 </ b> B, and then the image data is read from the image memory 56. read out.

  When the image data is read from the image memory 56, the electronic cassette 40 resets the pixels 32 of the radiation detection pixels 32 </ b> A and the radiation image acquisition pixels 32 </ b> B again, and then transfers the image data from the image generation unit power supply 54 </ b> A to the image generation unit 54. Stop power supply.

  Incidentally, in the electronic cassette 40 according to the present embodiment, as shown in FIG. 8, the radiation detector 20 is incorporated so that the radiation X is irradiated from the TFT substrate 30 side.

  Here, as shown in FIG. 16, the radiation detector 20 is irradiated with radiation from the side on which the scintillator 8 is formed, and reads a radiation image by the TFT substrate 30 provided on the back side of the incident surface of the radiation. In the case of a so-called back surface reading method, light is emitted more strongly on the upper surface side of the scintillator 8 (opposite side of the TFT substrate 30), radiation is irradiated from the TFT substrate 30 side, and the surface side of the incident surface of the radiation In the case of a so-called surface reading method in which a radiation image is read by the TFT substrate 30 provided on the TFT substrate 30, the radiation transmitted through the TFT substrate 30 enters the scintillator 8 and the TFT substrate 30 side of the scintillator 8 emits light more strongly. Electric charges are generated in each sensor unit 13 provided on the TFT substrate 30 by light generated by the scintillator 8. For this reason, since the radiation detector 20 is closer to the light emission position of the scintillator 8 with respect to the TFT substrate 30 when the front surface reading method is used than when the rear surface reading method is used, the resolution of the radiation image obtained by imaging is higher. high.

  In the radiation detector 20, the photoelectric conversion film 4 is made of an organic photoelectric conversion material, and the photoelectric conversion film 4 hardly absorbs radiation. For this reason, the radiation detector 20 according to the present embodiment suppresses a decrease in sensitivity to radiation because the amount of radiation absorbed by the photoelectric conversion film 4 is small even when radiation is transmitted through the TFT substrate 30 by the surface reading method. Can do. In the surface reading method, radiation passes through the TFT substrate 30 and reaches the scintillator 8. Thus, when the photoelectric conversion film 4 of the TFT substrate 30 is made of an organic photoelectric conversion material, the radiation in the photoelectric conversion film 4 is obtained. Therefore, it is suitable for the surface reading method.

  In addition, both the amorphous oxide constituting the active layer 17 of the thin film transistor 10 and the organic photoelectric conversion material constituting the photoelectric conversion film 4 can be formed at a low temperature. For this reason, the board | substrate 1 can be formed with a plastic resin, aramid, and bio-nanofiber with little radiation absorption. Since the substrate 1 formed in this way has a small amount of radiation absorption, even when the radiation passes through the TFT substrate 30 by the surface reading method, it is possible to suppress a decrease in sensitivity to radiation.

  Further, according to the present embodiment, as shown in FIG. 8, the radiation detector 20 is attached to the top plate 41B in the casing 41 so that the TFT substrate 30 is on the top plate 41B side. When 1 is formed of a highly rigid plastic resin, aramid, or bio-nanofiber, the radiation detector 20 itself has high rigidity, so that the top plate 41B of the housing 41 can be formed thin. In addition, when the substrate 1 is formed of a highly rigid plastic resin, aramid, or bionanofiber, the radiation detector 20 itself has flexibility, so that even when an impact is applied to the imaging region 41A, the radiation detector 20 is damaged. It ’s hard.

  As described above in detail, in the present embodiment, the first amplifier (the variable gain preamplifier 82 in the present embodiment) has a generation means (image generation in the present embodiment) that generates image information. Unit 54) and a second amplifier (in this embodiment, a variable gain preamplifier 92) and a detection means (in this embodiment, a radiation irradiation detection unit) that detects the radiation irradiation state. 55) is controlled so that at least a part of one period of the power supply period with respect to 55) is different from the other period, it is possible to prevent the occurrence of artifacts while suppressing power consumption.

  In particular, in the present embodiment, since the control is performed by stopping the power supply to the detection unit when the image information is generated by the generation unit, the generation of artifacts can be prevented more reliably.

  In the present embodiment, since the detection target of the irradiation state of the radiation by the detection unit is the start of radiation irradiation and the end of radiation irradiation, these irradiation states can be reduced in power consumption and artifacts. It is possible to detect while preventing the occurrence.

  Furthermore, in the present embodiment, the timing at which the input of the shooting condition information indicating the shooting conditions (initial information in the present embodiment) is completed is set as the start timing of the power supply period to the detection unit. Power consumption can be suppressed accurately.

[Second Embodiment]
In the first embodiment described above, an example in which power is supplied to both the image generation unit 54 and the radiation irradiation detection unit 55 when detecting the start of radiation irradiation has been described. In the embodiment, an example of a case in which power is not supplied to the image generation unit 54 when detecting the start of radiation irradiation will be described. Note that the configurations of the RIS 100, the radiation imaging room, the electronic cassette 40, and the imaging system 104 according to the second embodiment are the same as those in the first embodiment, and a description thereof is omitted here.

  Next, the operation of the imaging system 104 according to the second embodiment will be described. Note that the operation of the console 110 when taking a radiographic image according to the second embodiment is the same as that of the first embodiment, so the description thereof is omitted, and FIG. The operation of the electronic cassette 40 according to the second exemplary embodiment when the initial information is received from the console 110 will be described with reference to FIG. FIG. 17 is a flowchart showing a flow of processing of the cassette photographing processing program executed by the CPU 58A in the cassette control unit 58 of the electronic cassette 40 according to the second embodiment at this time. It is stored in advance in a predetermined area of 58B. In addition, steps in FIG. 14 that perform the same processing as in FIG. 14 are denoted by the same step numbers as in FIG.

  As shown in FIG. 17, the cassette imaging processing program according to the second embodiment is the process of step 400 in the cassette imaging processing program according to the first embodiment, that is, the image generation from the image generation unit power supply 54A. The process of controlling the image generation unit power supply 54A so as to start the power supply to the unit 54 is not executed, and the process is performed as a process of step 417, and after it is detected that radiation irradiation has started, and Only the point which is executed before starting the reading of the image data is different from the cassette photographing processing program according to the first embodiment.

  FIG. 18 schematically shows an example of the state transition of the main part during execution of the radiographic image capturing processing program and the cassette imaging processing program according to the second embodiment.

  As shown in the figure, in the second embodiment, only the timing at which power supply to the image generation unit 54 is started is just before the start of reading of image data. The form is different.

  The second embodiment can achieve substantially the same effect as the first embodiment, and also stops the power supply to the image generation unit 54 when detecting the start of radiation irradiation. Therefore, power consumption can be further reduced as compared with the first embodiment.

  As mentioned above, although this invention was demonstrated using embodiment, the technical scope of this invention is not limited to the range as described in the said embodiment. Various modifications or improvements can be added to the above-described embodiment without departing from the gist of the invention, and embodiments to which such modifications or improvements are added are also included in the technical scope of the present invention.

  The above embodiments do not limit the invention according to the claims (claims), and all the combinations of features described in the embodiments are essential for the solution means of the invention. Is not limited. The embodiments described above include inventions at various stages, and various inventions can be extracted by appropriately combining a plurality of disclosed constituent elements. Even if some constituent requirements are deleted from all the constituent requirements shown in the embodiment, as long as an effect is obtained, a configuration from which these some constituent requirements are deleted can be extracted as an invention.

  For example, in each of the above embodiments, as shown in FIG. 6, when the radiation detection pixels 32 </ b> A are arranged symmetrically with respect to both the vertical direction and the horizontal direction in the center detection area and the peripheral edge detection area. However, the present invention is not limited to this, and the arrangement position of the radiation detection pixels 32A is not particularly limited. However, as in the present embodiment, it is possible to use the electronic cassette 40 so as to be symmetric with respect to both the vertical direction and the horizontal direction without worrying about the vertical and horizontal directions of the electronic cassette 40, thus improving the usability. This is preferable.

  Here, when the radiation detection pixels 32A are arranged so as not to be symmetrical with respect to the top, bottom, left and right, the electronic cassette 40 is provided with direction detecting means such as an acceleration sensor, a gyro, etc., and the electronic cassette specified thereby is provided. The position of the radiation detection pixel 32 </ b> A may be specified according to the direction of 40.

  In each of the above embodiments, a part of the pixel 32 provided in the radiation detector 20 is used as the radiation detection pixel 32A, so that the adjacent radiation detection pixel 32A can perform defect pixel correction. Needless to say, they are preferably separated from each other.

  In each of the above embodiments, the case where the radiation detection pixel 32A is used for detecting the start of radiation irradiation and the end of radiation irradiation has been described. However, the present invention is not limited to this and is variable. In integration or cumulative addition of the output of the gain preamplifier 92, the radiation dose is obtained and the timing of the appropriate dose is detected, or the maximum value of the output of the variable gain preamplifier 92 is obtained to obtain fluoroscopic imaging. The radiation detection pixel 32A may be used to detect the radiation dose rate per unit time of radiation depending on the tube voltage and tube current of the radiation source for exposure management.

  In each of the above embodiments, the radiation detection pixels 32A arranged in the row direction in the radiation detector 20 are connected to the common direct readout wiring 38. However, the present invention is not limited to this. Alternatively, all the radiation detection pixels 32A may be individually connected to different direct readout wirings 38.

  In each of the above embodiments, the case where the power supply to the radiation irradiation detection unit 55 is started at the timing when the input of the initial information is completed has been described, but the present invention is not limited to this, for example, A switch that is pressed by a photographer or the like when exposing the radiation may be provided, and power supply to the radiation irradiation detection unit 55 may be started at a timing when the switch is pressed.

  Further, in each of the above embodiments, the case where the power supply to the radiation irradiation detection unit 55 is stopped when the image reading is performed has been described. However, the present invention is not limited to this, and for example, the image reading is performed. While performing the power supply to the radiation irradiation detection unit 55, the power supply to the image generation unit 54 may be stopped when the start of radiation irradiation is detected.

  Further, in each of the above-described embodiments, the case has been described in which the radiation generation apparatus 120 performs exposure of radiation by the radiation source 121 when the exposure conditions are set from the console 110 and the start of exposure is instructed. The present invention is not limited to this. For example, the radiation generator 120 is provided with a switch operated by a photographer or the like when starting radiation exposure and ending the radiation exposure. The radiation source control unit 122 of the radiation generation apparatus 120 may control the radiation exposure so as to start and end the radiation exposure according to the operation on the switch.

  In the second embodiment, the case where the power supply to the image generation unit 54 is started immediately before the image data is read has been described. However, the present invention is not limited to this. The power to the image generation unit 54 at any timing after it is detected that radiation irradiation has started, such as immediately after it is detected that irradiation has started, and before reading of image data is started It is good also as a form which starts supply.

  Further, in each of the above embodiments, the case where the present invention is applied to a mode for controlling the power supply to the image generation unit 54 and the radiation irradiation detection unit 55 has been described, but the present invention is not limited to this. For example, you may apply to the form which controls the power supply of the bias voltage to the pixel 32A for radiation detection, and the pixel 32B for radiation image acquisition, and also the power supply to the image generation part 54 and the radiation irradiation detection part 55, You may apply to the form which controls both the power supply of the bias voltage to 32 A of radiation detection pixels, and the radiation image acquisition pixel 32B.

  In each of the above-described embodiments, the case where a part of the pixels 32 provided in the radiation detector 20 is used as the radiation detection pixel 32A corresponding to the radiation detection element of the present invention has been described. For example, as disclosed in Japanese Patent No. 4217443, for example, the radiation detection pixel 32A may be stacked on the radiation detector 20 as a separate layer from the pixel 32. As an example, as disclosed in Japanese Patent No. 4217506, a radiation detection element that acts in the same manner as the radiation detection pixel 32A may be provided in addition to the pixel 32. In this case, since defective pixels do not occur, the quality of the radiation image can be improved as compared with the above embodiments.

  In each of the above embodiments, the radiation detection pixel 32A has been described as a dedicated pixel for detecting radiation. However, the present invention is not limited to this, and the radiation detection pixel 32A is a radiation detector. It is good also as a form which serves as the image acquisition pixel 32B. As an example of the form in this case, as disclosed in Japanese Patent Application Laid-Open No. 2009-219538, an example of detecting the radiation irradiation state based on a change in bias current flowing through each pixel is exemplified.

  In each of the above embodiments, the case where the radiation detection element of the present invention is provided on the TFT substrate 30 has been described. However, the present invention is not limited to this, for example, the TFT substrate inside the electronic cassette 40 It may be provided on a substrate different from 30, and may be provided separately from the electronic cassette 40 so as to overlap the radiation incident side or the opposite side of the incident side. In this case, the same effects as those of the above embodiments can be obtained.

  Further, in each of the above embodiments, the case where the sensor unit 13 is configured to include an organic photoelectric conversion material that generates charges by receiving light generated by the scintillator 8 has been described. It is good also as a form which applies what was constituted without including an organic photoelectric conversion material as sensor part 13 without being limited to.

  Further, in each of the above-described embodiments, the case has been described in which the case 42 that accommodates the cassette control unit 58 and the power supply unit 70 and the radiation detector 20 are arranged so as not to overlap each other inside the casing 41 of the electronic cassette 40. However, the present invention is not limited to this. For example, the radiation detector 20 and the cassette control unit 58 or the power supply unit 70 may be arranged so as to overlap each other.

  In each of the above embodiments, the case where wireless communication is performed between the electronic cassette 40 and the console 110 and between the radiation generator 120 and the console 110 has been described, but the present invention is not limited thereto. For example, at least one of these may be configured to perform wired communication.

  In each of the above embodiments, the case where X-rays are applied as radiation has been described. However, the present invention is not limited to this, and other radiation such as γ-rays may be applied.

  In addition, the configuration of the RIS 100 described in the above embodiments (see FIG. 1), the configuration of the radiation imaging room (see FIG. 2), the configuration of the electronic cassette 40 (see FIGS. 3 to 8 and 10), The configuration of the photographing system 104 (see FIG. 9) is an example, and unnecessary portions are deleted, new portions are added, connection states, etc. are changed within a range not departing from the gist of the present invention. It goes without saying that you can do it.

  The configuration of the initial information described in the above embodiments is also an example, and it is possible to delete unnecessary information or add new information without departing from the gist of the present invention. Needless to say.

  The processing flow of various programs described in the above embodiments (see FIGS. 12, 14, and 17) is also an example, and unnecessary steps are deleted without departing from the gist of the present invention. It goes without saying that new steps can be added and the processing order can be changed.

  The configuration of the initial information input screen described in the above embodiments (see FIG. 13) is also an example, and unnecessary information can be deleted or new information can be deleted without departing from the gist of the present invention. Needless to say, it can be added.

  In addition, the state transition of the main part described in each of the above embodiments (see FIGS. 15 and 18) is also an example, and unnecessary operations can be deleted or new within the scope not departing from the gist of the present invention. Needless to say, you can add actions.

  For example, in each of the above embodiments, each pixel 32 is reset after image reading is completed, but the reset need not necessarily be executed.

DESCRIPTION OF SYMBOLS 1 Substrate 8 Scintillator 10 Thin film transistor 13 Sensor part 20 Radiation detector 30 TFT substrate 32 Pixel 32A Radiation detection pixel (radiation detection element)
32B Radiation image acquisition pixel 36 Data wiring (signal wiring)
38 Direct readout wiring (radiation detection wiring)
40 Electronic cassette 54 Image generation unit (generation means)
55 Radiation irradiation detection part (detection means)
58 cassette control unit (control means, acceptance means)
58A CPU
82 Variable gain preamplifier (first amplifier)
84 Sample hold circuit 86 Multiplexer 88 A / D converter 92 Variable gain preamplifier (second amplifier)
94 Irradiation judgment circuit 110 Console 120 Radiation generator X Radiation

Claims (7)

A detection area for detecting radiation is provided in a matrix, and includes a sensor unit that generates charges when irradiated with radiation or light converted from radiation, and a switch element for reading out the charges generated in the sensor unit. A plurality of pixels;
Each of the plurality of pixels has the same configuration , provided in the detection region on the same substrate as the plurality of pixels, and an electric signal corresponding to the electric charge generated in the sensor unit according to the radiation dose An output radiation detection element;
For each of the plurality of pixels, a plurality of signal wirings through which an electrical signal corresponding to the electric charge generated in the sensor unit of the pixel according to the switching state of the switch element flows,
A first amplifier that is driven by power supply and amplifies each of the electric signals flowing through the plurality of signal wirings, and generates image information based on the electric signal amplified by the first amplifier. Generating means;
At least one radiation detection wiring that is directly connected to the sensor portion of the radiation detection element without a switch element, and through which an electrical signal output from the radiation detection element flows;
It has a second amplifier that is driven by power supply and amplifies an electric signal flowing through the radiation detection wiring, and detects the irradiation state of radiation based on the electric signal amplified by the second amplifier Detecting means for performing
At least a part of one of the power supply period for the generating unit and the power supply period for the detection unit is controlled to be different from the other period, and it is detected by the detection unit that the irradiation of radiation has ended. Control means for controlling the power supply to the detection means to be stopped when
A radiographic imaging apparatus comprising: The radiographic imaging apparatus according to claim 1, wherein the control unit performs the control by stopping power supply to the generation unit during detection of a radiation irradiation state by the detection unit. The detection target of the irradiation state of the radiation by the detecting unit further includes at least one of radiation irradiation start, radiation irradiation amount, and radiation dose rate per unit time. Radiation imaging device. The detection target of the irradiation state of the radiation by the detection means includes radiation irradiation start,
A reception unit for receiving input of shooting condition information indicating the shooting condition;
The radiation according to any one of claims 1 to 3, wherein the control unit sets a timing at which the reception of the input of the imaging condition information by the reception unit is ended as a start timing of a power supply period for the detection unit. Image shooting device. It further includes a switch that is pressed when the radiation is exposed,
The radiographic imaging apparatus according to any one of claims 1 to 3, wherein the control unit performs control so that power supply to the detection unit is started at a timing when the switch is pressed. The radiographic imaging according to any one of claims 1 to 5, wherein the control unit controls the power supply to the generation unit to stop when the generation of the image information by the generation unit is completed. apparatus. A detection area for detecting radiation is provided in a matrix, and includes a sensor unit that generates charges when irradiated with radiation or light converted from radiation, and a switch element for reading out the charges generated in the sensor unit. A plurality of pixels and the same configuration as each of the plurality of pixels are provided in the detection region on the same substrate as the plurality of pixels, and charge generated in the sensor unit according to the radiation dose A radiation detection element that outputs a corresponding electrical signal, and a plurality of signal wirings through which an electrical signal corresponding to a charge generated in a sensor unit of the pixel flows according to a switching state of the switch element for each of the plurality of pixels And a first amplifier that is driven by power supply and amplifies each of the electric signals flowing through the plurality of signal lines, and is amplified by the first amplifier. Based on the electrical signal, generating means for generating image information, is connected directly without passing through the switching element to the sensor portion of the radiation detection element, the at least one electrical signal output from the radiation detecting element flows radiation A detection wiring and a second amplifier that is driven by power supply and amplifies an electric signal flowing through the radiation detection wiring, and based on the electric signal amplified by the second amplifier, A program executed by a radiographic imaging device comprising a detection means for detecting the irradiation state of
Computer
Receiving means for receiving input of shooting condition information indicating shooting conditions;
The timing at which the reception of the input of the photographing condition information by the reception unit is completed is set as the timing of starting the power supply period for the detection unit, and one of the power supply period for the generation unit and the power supply period for the detection unit Control means for controlling so that at least a part is different from the other period, and for stopping power supply to the detection means when it is detected by the detection means that irradiation of radiation has been completed; ,
Program to function as.

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