JPWO2010131506A1 - Radiation imaging equipment - Google Patents

Abstract

Provided is a radiographic imaging apparatus capable of detecting the start of radiation irradiation and the like and capable of suppressing wasteful power consumption. For this purpose, the radiographic imaging apparatus 1 includes a plurality of radiation detection elements 7 arranged in a two-dimensional manner, switch means 8 arranged for each of the radiation detection elements 7 and capable of switching between an off state and an on state, and radiation irradiation. Current detection means 41 for detecting the current flowing through the apparatus, sub-control means 23 for detecting the start and / or end of radiation irradiation based on the detected current value, and the radiation detection element 7 Main control means 22 for performing image data read processing, the power consumption of the sub-control means 23 is less than the power consumption of the main control means 22, and radiation irradiation based on the current value detected by the current detection means 41. When the start and / or end is detected, the main control means 22 is activated and the sub-control means 23 is deactivated.

Description

  The present invention relates to a radiographic image capturing apparatus, and more particularly to a radiographic image capturing apparatus capable of detecting the start of radiation irradiation and the like.

  A so-called direct type radiographic imaging device that generates electric charges by a detection element in accordance with the dose of irradiated radiation such as X-rays and converts it into an electrical signal, or other radiation such as visible light with a scintillator or the like. Various so-called indirect radiographic imaging devices have been developed that convert charges to electromagnetic waves after being converted into electrical signals by generating electric charges with photoelectric conversion elements such as photodiodes in accordance with the energy of the converted and irradiated electromagnetic waves. Yes. In the present invention, the detection element in the direct type radiographic imaging apparatus and the photoelectric conversion element in the indirect type radiographic imaging apparatus are collectively referred to as a radiation detection element.

  This type of radiographic imaging apparatus is known as an FPD (Flat Panel Detector), and conventionally formed integrally with a support base (or a bucky apparatus) (see, for example, Patent Document 1). A portable radiographic imaging device in which an element or the like is housed in a housing has been developed and put into practical use (see, for example, Patent Documents 2 and 3).

  By the way, in these radiographic imaging apparatuses, particularly portable radiographic imaging apparatuses, information on the start and end of radiation irradiation is transmitted to the radiographic imaging apparatus from an external device such as a computer that manages the radiation irradiation apparatus and system. Accordingly, the radiation image capturing apparatus may be configured to read image data from each radiation detection element after the radiation irradiation ends.

  However, even if the radiation imaging device side completes the reset processing of the radiation detection element and enters the standby state for radiographic imaging, if it takes time to actually irradiate radiation from the radiation irradiation device, In some cases, dark charges are accumulated in the reset radiation detection element, and the quality of the obtained radiation image may deteriorate. Further, if the standby state continues for a long time, power is consumed correspondingly.

  Therefore, it is desirable to configure so that the start and end of radiation irradiation can be detected by the radiographic imaging apparatus itself, because accumulation of dark charges in the radiation detection element is suppressed. In addition, since the standby state is shortened or radiographic imaging can be performed immediately without going through the standby state, wasteful power consumption can be suppressed or avoided.

  At that time, it is possible to arrange a sensor or the like in the radiographic imaging apparatus so that the start or end of radiation irradiation is detected by the sensor, but the sensor is arranged in the radiographic imaging apparatus. Space is required, and the apparatus becomes large. Further, when the sensor is provided, there is a problem that a large amount of electric power is consumed for driving the sensor, and in particular, a portable radiographic imaging apparatus consumes a built-in battery.

  Thus, it has been proposed to detect a current flowing through a bias line for applying a bias voltage to each radiation detection element, and to detect the start or end of radiation irradiation by increasing or decreasing the current value (see Patent Document 4). ). With this configuration, since current detection means can be provided in existing wiring or the like, the start and end of radiation irradiation can be started and terminated relatively easily in a state in which power consumption is suppressed compared to the case where a sensor is provided. It becomes possible to detect.

JP-A-9-73144 JP 2006-58124 A JP-A-6-342099 US Pat. No. 7,211,803

  However, as described above, when the current detection unit is provided in the radiographic imaging apparatus, even if the power consumption is suppressed as compared with the case where a sensor for detecting the start or end of radiation irradiation is provided, There are many cases where consumption is large.

  In addition, when the power consumption is large in this way, especially in a portable radiographic image capturing apparatus with a built-in battery, the battery is consumed greatly. Use efficiency of the image capturing device is reduced.

  In addition, when the battery is exhausted and sufficient read power cannot be supplied from each radiation detection element that consumes a relatively large amount of power, and the read process cannot be performed, the radiographic imaging device is charged. In some cases, it may be necessary to perform radiographic imaging again using another radiographic imaging apparatus. However, this increases the exposure dose received by the patient as the subject, and places a heavy burden on the patient.

  Therefore, the radiographic imaging apparatus is provided with a current detection means and configured to detect the start and end of radiation irradiation by the apparatus itself, thereby not only suppressing and avoiding unnecessary power consumption, but also in the radiographic imaging apparatus. Further, it is desired that the power consumption be configured to be able to suppress wasteful power consumption as much as possible.

  The present invention has been made in view of the above-described problems, and provides a radiographic imaging apparatus that can detect the start of radiation irradiation and the like and that can suppress wasteful power consumption. Objective.

In order to solve the above-described problem, the radiographic imaging device of the present invention includes:
A plurality of scanning lines and a plurality of signal lines arranged so as to intersect with each other; a plurality of radiation detecting elements arranged in a two-dimensional manner in each region partitioned by the plurality of scanning lines and the plurality of signal lines; ,
Switch means arranged for each radiation detection element, holding the charge generated in the radiation detection element in the off state, and discharging the charge from the radiation detection element in the on state;
A readout circuit that converts the electric charge emitted from the radiation detection element into a voltage and reads it as image data;
Scanning drive means for switching between the OFF state and the ON state of each switch means via the scanning line;
In a radiographic imaging device comprising:
Current detecting means for detecting a current flowing in the apparatus with radiation,
Sub-control means for detecting the start and / or end of radiation irradiation based on the value of the current detected by the current detection means;
Main control means for controlling the scanning drive means and the readout circuit to perform the readout process of the image data from the radiation detection element;
With
The sub control means has less power consumption than the main control means,
When the start and / or end of radiation irradiation is detected based on the value of the current detected by the current detection means, the main control means is activated and the sub-control means is deactivated. And

  According to the radiographic imaging apparatus of the system of the present invention, processing that requires processing by operating various functional units, such as readout processing of image data from each radiation detection element and transmission of image data. Can be executed by activating only a specific functional unit, such as reset processing of each radiation detection element or monitoring of the start of radiation irradiation, etc. The processing is configured such that only necessary functional units are activated and the sub-control unit consumes less power than the main control unit.

  For this reason, it is possible to detect the start of radiation irradiation or the like by the radiation image capturing apparatus itself regardless of an external apparatus such as a radiation irradiation apparatus. At the same time, power is supplied only to the functional units necessary for each process such as detection of current flowing through the apparatus, reading process of image data, transmission of image data, etc. as radiation irradiation starts. Since power is not supplied to unnecessary function units, wasteful power consumption can be accurately suppressed.

  In addition, since power is not consumed in this way, battery consumption is suppressed particularly in a portable radiographic imaging apparatus with a built-in battery, and more radiographic imaging can be performed with a single charge. Thus, it is possible to improve the use efficiency of the radiographic image capturing apparatus. In addition, since battery consumption is suppressed, re-execution of radiographic imaging due to battery consumption can be avoided accurately. Therefore, it is possible to accurately prevent the exposure dose received by the patient as the subject from increasing and the burden on the patient from increasing.

It is a perspective view which shows the radiographic imaging apparatus which concerns on each embodiment. It is sectional drawing which follows the AA line in FIG. It is a top view which shows the structure of the board | substrate which concerns on this embodiment. It is an enlarged view which shows the structure of the radiation detection element, TFT, etc. which were formed in the small area | region on the board | substrate of FIG. It is sectional drawing which follows the XX line in FIG. It is a side view explaining the board | substrate with which COF, a PCB board | substrate, etc. were attached. It is a block diagram showing the equivalent circuit of the radiographic imaging apparatus which concerns on this embodiment. It is a block diagram showing the equivalent circuit about 1 pixel which comprises a detection part. FIG. 9A is an equivalent circuit diagram illustrating the configuration of the current detection unit and the feedback circuit, and FIG. 9B is a diagram illustrating a state in which the switch of the feedback circuit is switched. It is a graph showing the example of the voltage value corresponded to the electric current detected by an electric current detection means, FIG.10 (A) is the state by which irradiation of the radiation was started, FIG.10 (B) is the state by which irradiation of the radiation was complete | finished Represents. It is a block diagram showing the equivalent circuit of the radiographic imaging apparatus at the time of providing the current detection means which concerns on other embodiment between a power supply part and an amplifier circuit.

  Embodiments of a radiographic image capturing apparatus according to the present invention will be described below with reference to the drawings.

  In the following description, the radiographic imaging device is a so-called indirect radiographic imaging device that includes a scintillator or the like and converts the irradiated radiation into electromagnetic waves of other wavelengths such as visible light to obtain an electrical signal. As will be described, the present invention can also be applied to a direct radiographic imaging apparatus. Although the case where the radiographic image capturing apparatus is portable will be described, the present invention is also applicable to a radiographic image capturing apparatus formed integrally with a support base or the like.

  FIG. 1 is an external perspective view of the radiographic image capturing apparatus according to the present embodiment, and FIG. 2 is a cross-sectional view taken along line AA in FIG. As shown in FIGS. 1 and 2, the radiographic imaging apparatus 1 according to the present embodiment is configured as a portable (cassette type) apparatus in which a scintillator 3, a substrate 4, and the like are housed in a housing 2. .

  The housing 2 is formed of a material such as a carbon plate or plastic that transmits radiation at least on a surface R (hereinafter referred to as a radiation incident surface R) that receives radiation. 1 and 2 show a case in which the housing 2 is a so-called lunch box type formed by the frame plate 2A and the back plate 2B. However, the housing 2 is integrally formed in a rectangular tube shape. It is also possible to use a so-called monocoque type.

  As shown in FIG. 1, the side surface of the housing 2 is opened and closed to replace a power switch 36, an indicator 37 composed of LEDs and the like, and a battery 40 (not shown) (see FIG. 7 described later). A possible lid member 38 and the like are arranged. In the present embodiment, an antenna device 39 that is a communication unit for wirelessly communicating with an external device is embedded in the side surface of the lid member 38.

  As shown in FIG. 2, a base 31 is disposed inside the housing 2 via a thin lead plate or the like (not shown) on the lower side of the substrate 4. The disposed PCB substrate 33, the buffer member 34, and the like are attached. In the present embodiment, a glass substrate 35 for protecting the substrate 4 and the radiation incident surface R of the scintillator 3 is disposed.

  The scintillator 3 is attached to a detection unit P, which will be described later, of the substrate 4. As the scintillator 3, for example, a scintillator 3 that has a phosphor as a main component and converts it into an electromagnetic wave having a wavelength of 300 to 800 nm, that is, an electromagnetic wave centered on visible light when it receives incident radiation, is used.

  In the present embodiment, the substrate 4 is formed of a glass substrate. As shown in FIG. 3, a plurality of scanning lines 5 and a plurality of signal lines are provided on a surface 4 a of the substrate 4 facing the scintillator 3. 6 are arranged so as to cross each other. In each small region r defined by the plurality of scanning lines 5 and the plurality of signal lines 6 on the surface 4 a of the substrate 4, radiation detection elements 7 are respectively provided.

  Thus, the entire region r in which a plurality of radiation detection elements 7 arranged in a two-dimensional manner are provided in each small region r partitioned by the scanning line 5 and the signal line 6, that is, shown by a one-dot chain line in FIG. The region is a detection unit P.

  In the present embodiment, a photodiode is used as the radiation detection element 7, but other than this, for example, a phototransistor or the like can also be used. Each radiation detection element 7 is connected to the source electrode 8s of the TFT 8 serving as a switch means, as shown in the enlarged views of FIGS. The drain electrode 8 d of the TFT 8 is connected to the signal line 6.

  The TFT 8 is turned on when a turn-on voltage is applied to the connected scanning line 5 by the scanning drive means 15 described later and applied to the gate electrode 8g, and is generated and accumulated in the radiation detection element 7. The charged electric charge is discharged to the signal line 6. The TFT 8 is turned off when the off voltage is applied to the connected scanning line 5 and the off voltage is applied to the gate electrode 8g, and the discharge of the charge from the radiation detecting element 7 to the signal line 6 is stopped. Electric charges generated in the radiation detection element 7 are held and accumulated in the radiation detection element 7.

  Here, the structure of the radiation detection element 7 and the TFT 8 in this embodiment will be briefly described with reference to the cross-sectional view shown in FIG. FIG. 5 is a sectional view taken along line XX in FIG.

A gate electrode 8g of a TFT 8 made of Al, Cr or the like is formed on the surface 4a of the substrate 4 so as to be integrally laminated with the scanning line 5, and silicon nitride (laminated on the gate electrode 8g and the surface 4a). The first electrode 74 of the radiation detecting element 7 is connected to the upper portion of the gate electrode 8g on the gate insulating layer 81 made of SiN _x ) or the like via the semiconductor layer 82 made of hydrogenated amorphous silicon (a-Si) or the like. The formed source electrode 8s and the drain electrode 8d formed integrally with the signal line 6 are laminated.

The source electrode 8s and the drain electrode 8d are divided by a first passivation layer 83 made of silicon nitride (SiN _x ) or the like, and the first passivation layer 83 covers both electrodes 8s and 8d from above. In addition, ohmic contact layers 84a and 84b formed in an n-type by doping hydrogenated amorphous silicon with a group VI element are laminated between the semiconductor layer 82 and the source electrode 8s and the drain electrode 8d, respectively. The TFT 8 is formed as described above.

  In the radiation detecting element 7, an auxiliary electrode 72 is formed by laminating Al, Cr, or the like on the insulating layer 71 formed integrally with the gate insulating layer 81 on the surface 4 a of the substrate 4. A first electrode 74 made of Al, Cr, Mo or the like is laminated on the auxiliary electrode 72 with an insulating layer 73 formed integrally with the first passivation layer 83 interposed therebetween. The first electrode 74 is connected to the source electrode 8 s of the TFT 8 through the hole H formed in the first passivation layer 83.

  On the first electrode 74, an n layer 75 formed in an n-type by doping a hydrogenated amorphous silicon with a group VI element, an i layer 76 which is a conversion layer formed of hydrogenated amorphous silicon, and a hydrogenated amorphous A p layer 77 formed by doping a group III element into silicon and forming a p-type layer is formed by laminating sequentially from below.

  When radiation enters from the radiation incident surface R of the housing 2 of the radiographic imaging apparatus 1 and is converted into an electromagnetic wave such as visible light by the scintillator 3, and the converted electromagnetic wave is irradiated from above in the figure, the electromagnetic wave is detected by radiation. The electron hole pair is generated in the i layer 76 by reaching the i layer 76 of the element 7. In this way, the radiation detection element 7 converts the electromagnetic waves irradiated from the scintillator 3 into electric charges.

  On the p layer 77, a second electrode 78 made of a transparent electrode such as ITO is laminated and formed so that the irradiated electromagnetic wave reaches the i layer 76 and the like. In the present embodiment, the radiation detection element 7 is formed as described above. The order of stacking the p layer 77, the i layer 76, and the n layer 75 may be reversed. Further, in the present embodiment, a case where a so-called pin-type radiation detection element formed by sequentially stacking the p layer 77, the i layer 76, and the n layer 75 as described above is used as the radiation detection element 7. However, it is not limited to this.

A bias line 9 for applying a bias voltage to the radiation detection element 7 is connected to the upper surface of the second electrode 78 of the radiation detection element 7 via the second electrode 78. The second electrode 78 and the bias line 9 of the radiation detection element 7, the first electrode 74 extended to the TFT 8 side, the first passivation layer 83 of the TFT 8, that is, the upper surfaces of the radiation detection element 7 and the TFT 8 are A second passivation layer 79 made of silicon nitride (SiN _x ) or the like is covered from above.

  As shown in FIGS. 3 and 4, in this embodiment, one bias line 9 is connected to a plurality of radiation detection elements 7 arranged in rows, and each bias line 9 is connected to a signal line 6. Are arranged in parallel with each other. In addition, each bias line 9 is bound to one connection 10 at a position outside the detection portion P of the substrate 4.

  In this embodiment, as shown in FIG. 3, each scanning line 5, each signal line 6, and connection 10 of the bias line 9 are input / output terminals (also referred to as pads) provided near the edge of the substrate 4. 11 is connected. As shown in FIG. 6, a COF (Chip On Film) 12 in which a chip such as a gate IC 12a functioning as a gate driver 15b of a scanning drive unit 15 described later is incorporated in each input / output terminal 11 is anisotropically conductively bonded. They are connected via an anisotropic conductive adhesive material 13 such as a film (Anisotropic Conductive Film) or an anisotropic conductive paste (Anisotropic Conductive Paste).

  The COF 12 is routed to the back surface 4b side of the substrate 4 and connected to the PCB substrate 33 described above on the back surface 4b side. Thus, the board | substrate 4 part of the radiographic imaging apparatus 1 is formed. In FIG. 6, illustration of the electronic component 32 and the like is omitted.

  Here, the circuit configuration of the radiation image capturing apparatus 1 will be described. FIG. 7 is a block diagram showing an equivalent circuit of the radiographic imaging apparatus 1 according to the present embodiment, and FIG. 8 is a block diagram showing an equivalent circuit for one pixel constituting the detection unit P.

  As described above, each radiation detection element 7 of the detection unit P of the substrate 4 has the bias line 9 connected to the second electrode 78, and each bias line 9 is bound to the connection 10 to the bias power supply 14. It is connected. The bias power supply 14 applies a bias voltage to the second electrode 78 of each radiation detection element 7 via the connection 10 and each bias line 9.

  In the present embodiment, as can be seen from the fact that the bias line 9 is connected to the p-layer 77 side (see FIG. 5) of the radiation detection element 7 via the second electrode 78, A voltage lower than the voltage applied to the first electrode 74 side of the radiation detection element 7 (that is, a so-called reverse bias voltage) is applied to the second electrode 78 of the radiation detection element 7 as a bias voltage via the bias line 9. Yes.

  In the present embodiment, the bias power source 14 is connected to a main control unit 22 and a sub control unit 23 described later, and the main control unit 22 and the sub control unit 23 apply each radiation detection element 7 from the bias power source 14. The bias voltage is made variable as necessary.

  Further, in the present embodiment, current detection is performed to detect a current flowing between the bias power supply 14 and the radiation detection element 7 at the connection portion between the connection 10 of the bias line 9 and the bias power supply 14 as radiation starts. Means 41 are provided. The configuration of the current detection unit 41 will be described later.

  The first electrode 74 of each radiation detection element 7 is connected to the source electrode 8s of the TFT 8 (indicated as S in FIGS. 7 and 8), and the gate electrode 8g of each TFT 8 (FIGS. 7 and 8). Are respectively connected to the lines L1 to Lx of each scanning line 5 extending from a gate driver 15b of the scanning driving means 15 described later. Further, the drain electrode 8 d (denoted as D in FIGS. 7 and 8) of each TFT 8 is connected to each signal line 6.

  In this embodiment, the scanning drive unit 15 includes a power supply circuit 15a and a gate driver 15b. In this embodiment, the gate driver 15b is formed by arranging a plurality of the gate ICs 12a described above in parallel. Further, the scanning drive means 15 controls the voltage applied to the gate electrode 8g of the TFT 8 via each scanning line 5 connected to the gate driver 15b.

  Each signal line 6 is connected to each readout circuit 17 formed in the readout IC 16. Note that a predetermined number of readout circuits 17 are provided in the readout IC 16, and by providing a plurality of readout ICs 16, readout circuits 17 corresponding to the number of signal lines 6 are provided.

  The readout circuit 17 includes an amplifier circuit 18, a correlated double sampling circuit 19, an analog multiplexer 21, and an A / D converter 20. 7 and 8, the correlated double sampling circuit 19 is represented as CDS. In FIG. 8, the analog multiplexer 21 is omitted.

In the present embodiment, the amplifier circuit 18 is configured by a charge amplifier circuit, and is configured by connecting a capacitor 18b and a charge reset switch 18c in parallel to the operational amplifier 18a and the operational amplifier 18a. Further, the signal line 6 is connected to the inverting input terminal on the input side of the operational amplifier 18 a of the amplifier circuit 18, and the reference potential V ₀ is applied to the non-inverting input terminal on the input side of the amplifier circuit 18. ing. Note that the reference potential V ₀ is set to an appropriate value, and in this embodiment, for example, 0 [V] is applied.

  The charge reset switch 18c of the amplifier circuit 18 is connected to the main control means 22 and the sub-control means 23, and is controlled to be turned on / off by the main control means 22 or the like. When the charge reset switch 18c is off and the TFT 8 of the radiation detection element 7 is turned on (that is, when an on-voltage is applied to the gate electrode 8g of the TFT 8 via the scanning line 5), the radiation The electric charge discharged from the detection element 7 flows into the capacitor 18b and is accumulated, and a voltage value corresponding to the accumulated electric charge is output from the output terminal of the operational amplifier 18a.

  In this way, the amplifier circuit 18 outputs a voltage in accordance with the amount of charge output from each radiation detection element 7, converts the charge voltage, and amplifies it. When the charge reset switch 18c is turned on, the input side and the output side of the amplifier circuit 18 are short-circuited, and the charge accumulated in the capacitor 18b is discharged to reset the amplifier circuit 18. ing.

  Note that the amplifier circuit 18 may be configured to output a current in accordance with the charge output from the radiation detection element 7. Further, as shown in FIG. 8, power is supplied from the power supply unit 42 to the amplifier circuit 18. In FIG. 7, the power supply unit 42 is not shown.

  A correlated double sampling circuit (CDS) 19 is connected to the output side of the amplifier circuit 18. In this embodiment, the correlated double sampling circuit 19 has a sample and hold function. The sample and hold function in the correlated double sampling circuit 19 is turned on / off by a pulse signal transmitted from the main control means 22. Is to be controlled.

  That is, the correlated double sampling circuit 19 is emitted from the radiation detection element 7 when the image data is read from each radiation detection element 7 after the amplifier circuit 18 is reset and the charge reset switch 18c is turned off. When the first pulse signal is received from the main control means 22 at the time when the accumulated electric charge flows into the capacitor 18b and starts to be accumulated, the voltage value output from the amplifier circuit 18 at that time is held.

  Then, when a second pulse signal is received from the main control means 22 at the time when the charge discharged from the radiation detecting element 7 flows into the capacitor 18b and is accumulated after a predetermined time has elapsed from that time, it is again at that time. The voltage value output from the amplifier circuit 18 is held, and the difference value between these voltage values is output downstream as image data.

  The image data of each radiation detection element 7 output from the correlated double sampling circuit 19 is transmitted to the analog multiplexer 21 and sequentially transmitted from the analog multiplexer 21 to the A / D converter 20. Then, the A / D converter 20 sequentially converts the image data into digital values, which are output to the storage means 43 and sequentially stored.

  In this embodiment, the main control means 22 is a computer or FPGA (Field Programmable) in which a CPU (Central Processing Unit), a ROM (Read Only Memory), a RAM (Random Access Memory), an input / output interface, and the like (not shown) are connected to the bus. Gate Array).

  In the present embodiment, the sub-control means 23 is constituted by a microcomputer (also referred to as a microprocessor). The sub-control unit 23 uses less power than the main control unit 22.

  Both the main control means 22 and the sub-control means 23 are configured to switch the operating state between an activated state and a deactivated state of activation. In the present embodiment, the activation stop state is a slight energization, that is, activation from the other side, that is, from the sub control unit 23 in the main control unit 22 and from the main control unit 22 in the sub control unit 23. A sleep state in which only an activation signal for instructing can be received. Further, when the radiographic imaging apparatus 1 is turned off by an operator such as a radiographer, the main control unit 22 and the sub control unit 23 are in a so-called off state in which energization is completely stopped.

  In this embodiment, when the operator depresses the power switch 36 (see FIG. 1) and the radiographic imaging apparatus 1 is turned on, the sub-control unit 23 is activated, and the main control unit 22 stops activation. It is configured to enter a state, that is, a sleep state. Then, when the sub-control unit 23 detects the start or end of radiation irradiation to the radiographic imaging apparatus 1 based on the current value detected by the current detection unit 41, the sub-control unit 23 transmits an activation signal to the main control unit 22 to The control means 22 is activated, and the activation of the sub-control means 23 itself is stopped.

  When the main control unit 22 finishes reading the image data from each radiation detection element 7 and transmitting the image data to the external device, an activation signal is transmitted from the main control unit 22 to the sub-control unit 23. The control means 23 is activated, and the main control means 22 itself is returned to the state where the activation is stopped.

  In this way, the main control means 22 is awakened only when image data reading processing from each radiation detection element 7 is performed, image data transmission to an external device, or the like. Otherwise, activation is stopped. It is supposed to be in the sleep state.

  As shown in FIGS. 7 and 8, the sub-control means 23 is connected to the bias power supply 14 and the charge reset switch 18c of the amplifier circuit 18, and is not shown in FIG. A supply unit 42 is also connected.

  Then, when the radiographic imaging apparatus 1 is turned on and activated, the sub-control unit 23 supplies power to the amplifier circuit 18 from the power supply unit 42 to activate the amplifier circuit 18. The control means 23 is configured to turn on the charge reset switch 18c. At this time, power is not supplied to the other functional units of the readout circuit 17, that is, the correlated double sampling circuit 19, the A / D converter 20, the analog multiplexer 21, and the like, so that they are not activated.

  The sub-control unit 23 is connected to the scanning drive unit 15. The sub-control unit 23 starts up the bias power supply 14 and applies a bias voltage to each radiation detection element 7 via the bias line 9. Then, an on-voltage is applied to each scanning line 5 from the scanning drive means 15, an on-voltage is applied to the gate electrode 8 g of each TFT 8 connected to each scanning line 5, all the TFTs 8 are turned on, and the gates of all TFTs 8 are turned on. Is in an open state.

  When each functional unit is activated in this way, excess charge accumulated in each radiation detection element 7 passes through the TFT 8 and the charge reset switch 18c, and is output from the output terminal side of the operational amplifier 18a of the amplifier circuit 18 to the operational amplifier. It passes through the interior 18 a and is discharged to the power supply unit 42. In this way, the reset processing of each radiation detection element 7 is performed.

  In other words, in the present embodiment, the sub-control unit 23 supplies power only to the functional units necessary for the reset processing of each radiation detection element 7 and the detection of current by the current detection unit 41 described later. By not supplying power, unnecessary power consumption is avoided.

  The sub-control unit 23 is further connected to the above-described current detection unit 41, and the sub-control unit 23 detects the start of radiation irradiation based on the current value detected by the current detection unit 41. It has become.

  Here, the configuration of the current detection means 41 will be described. In the present embodiment, as described above, the current detection means 41 is provided at a connection portion between the connection 10 of the bias line 9 and the bias power supply 14, and the bias power supply 14 and the radiation detection element 7 are started with the start of radiation irradiation. The current flowing between the two is detected.

  Specifically, as shown in FIG. 9A, the current detection means 41 has a predetermined resistance value connected in series to the connection 10 of the bias wiring 9 that connects the bias power supply 14 and each radiation detection element 7. A resistor 41a, a diode 41b connected in parallel to the resistor 41a, and a differential amplifier 41c that measures the voltage V between both terminals of the resistor 41a and outputs the voltage V to the sub-control means 23.

  Thus, in this embodiment, the current detection means 41 measures the voltage V between both terminals of the resistor 41a by the differential amplifier 41c, and flows the current flowing through the resistor 41a, that is, the connection 10 of the bias line 9. The current is converted into a voltage value V, detected, and output to the sub-control means 23. As the resistor 41a provided in the current detection means 41, a resistor having a resistance value capable of converting a current flowing through the connection 10 into an appropriate voltage value V is used. The diode 41b is provided so that it can be detected even in a wide dynamic range such as a radiographic apparatus. It is also possible to have a configuration including only the resistor 41a or only the diode 41b.

  Further, in cases other than the case where the start or end of radiation irradiation is detected, it is not necessary to detect the current flowing between the bias power supply 14 and each radiation detection element 7 by the current detection means 41, and the current detection means 41 Since the resistor 41a hinders the application of a bias voltage from the bias power supply 14 to each radiation detection element 7, the current detection means 41 requires a gap between both terminals of the resistor 41a when current detection is not required. Accordingly, a switch 41d for short-circuiting is provided. Note that the switch 41d is not necessarily provided.

  Further, when the current detection means 41 detects the current flowing through the connection 10 of the bias line 9, the voltage V is generated between both terminals of the resistor 41 a of the current detection means 41 due to the current flowing through the connection 10. The bias voltage Vbias to be applied to the second electrode 78 side of each radiation detection element 7 may vary.

  Therefore, in the present embodiment, in order to suppress the fluctuation of the bias voltage Vbias, the current flow in the connection 10 is not disturbed between the current detection means 41 and each radiation detection element 7, and the voltage fluctuation is not disturbed. A feedback circuit 45 is provided for absorbing the above and applying a predetermined bias voltage Vbias to the second electrode 78 side of each radiation detection element 7.

  The feedback circuit 45 is a known circuit, and is configured, for example, by connecting the emitter of a PNP transistor 45a to the bias line 9 or the connection 10 and connecting the collector to the current detection means 41 side, and further to the emitter of the transistor 45a. The inverting input terminal is connected to the bias line 9 side, and the output of the amplifier 45b in which a predetermined bias voltage Vbias is applied from the bias power supply 14 to the non-inverting input terminal is input to the base of the transistor 45a. Yes.

  With this configuration, even when the current detection unit 41 is in operation, a predetermined bias voltage Vbias is stably applied from the feedback circuit 45 to the second electrode 78 side of each radiation detection element 7. ing.

  The feedback circuit 45 disconnects the connection between the inverting input terminal of the amplifier 45b and the connection 10 and the non-inverting input terminal and the bias power supply 14 when the current flowing through the connection 10 of the bias line 9 is not detected. A switch 45c for directly connecting the connection 10 of the bias line 9 and the bias power supply 14 is provided.

  When the current detection means 41 detects the current flowing through the connection 10 of the bias line 9, power is supplied from the power supply means 46 to the differential amplifier 41 c of the current detection means 41 and the amplifier 45 b of the feedback circuit 45. The current detection means 41 and the feedback circuit 45 are in operation. Then, the switch 45c connects the inverting input terminal of the amplifier 45b of the feedback circuit 45 to the connection 10 of the bias line 9, and the non-inverting input terminal to the bias power source 14. A predetermined bias voltage Vbias is stably applied to the two electrodes 78.

  When current detection is no longer necessary, the switch 45c on the input side of the amplifier 45b is switched as shown in FIG. 9B, and the connection 10 of the bias line 9 and the bias power supply 14 are directly connected. . As a result, a predetermined bias voltage Vbias is applied from the bias power supply 14 to the second electrode 78 of each radiation detection element 7 via the switch 45c, and the differential amplifier 41c and the feedback circuit of the current detection means 41 are supplied from the power supply means 46. The supply of power to the amplifier 45b of 45 is stopped, and the operation of the current detection means 41 and the feedback circuit 45 is stopped.

  In this way, the switch 45c is provided on the input side of the amplifier 45b of the feedback circuit 45, and the bias power supply 14 and the connection 10 are directly connected at the time of reading image data, so that the differential amplifier 41c of the current detecting means 41 and The operation of the power supply means 46 that supplies the amplifier 45b of the feedback circuit 45 can be stopped, and the power consumed by the transistor 45a can be suppressed. Therefore, power consumption can be suppressed.

  Then, radiographic imaging is started, and when radiation irradiation is started from a radiation irradiation device (not shown) to the radiation incident surface R (see FIG. 1) of the radiographic imaging device 1, as shown in FIG. At time t1 when radiation irradiation is started, the voltage value V corresponding to the current output from the differential amplifier 41c of the current detection means 41 increases rapidly.

  Therefore, in the present embodiment, the sub-control unit 23 increases the voltage value V output from the current detection unit 41, for example, when the preset threshold value is exceeded, or the increase rate of the voltage value V is set in advance. When the measured threshold value is exceeded, it is detected that radiation irradiation has started.

  Further, if the TFT 8 is left in the ON state as described above, all the charges generated in each radiation detection element 7 flow out, and no charges (image data) are accumulated in each radiation detection element 7. Therefore, when the sub-control unit 23 detects that the voltage value V has increased and the irradiation of radiation has started, the sub-control unit 23 applies an off voltage to each scanning line 5 from the scanning driving unit 15 and applies to each scanning line 5. All the TFTs 8 are turned off by applying a turn-off voltage to the gate electrodes 8g of the connected TFTs 8.

  The sub-control means 23 detects the start of radiation irradiation based on the voltage value V corresponding to the current detected by the current detection means 41 as described above (see time t1 in FIG. 10A), and each TFT 8 When the scanning drive unit 15 is controlled so as to turn off the power, an activation signal is transmitted to the main control unit 22 in order to cause the main control unit 22 to read out image data from each radiation detection element 7 and the like. The main control means 22 is activated.

  As shown in FIG. 10B, the voltage value V corresponding to the current output from the current detection means 41 greatly decreases at the time t2 when all the TFTs 8 are turned off, but the radiation irradiation is completed. Then, it further decreases at the time t3. Therefore, the sub-control unit 23 is configured to detect the end of radiation irradiation based on the fact that the voltage value V decreased when all the TFTs 8 are turned off, and detects the end of radiation irradiation. At this point, it is possible to configure the main control unit 22 to be activated, which is preferable because power consumption can be further suppressed.

  In this embodiment, the function of the sub-control unit 23 is to detect the start and / or end of radiation irradiation and to activate the main control unit 22 after this detection. For this reason, it is not necessary to activate the sub-control unit 23 after the main control unit 22 is activated. Therefore, when the main control unit 22 is activated, the sub-control unit 23 stops its activation, or The activation is stopped by a stop signal from the activated main control means 22.

  In this way, by configuring the sub-control unit 23 to stop when the main control unit 22 is activated, unnecessary power is supplied to the sub-control unit 23 and power is wasted. It becomes possible to prevent.

  It should be noted that the radiographic image capturing apparatus 1 is turned on by the operator and the sub-control unit 23 is activated, but no radiographic image is captured even after a long time has passed, that is, the sub-control unit. If 23 does not detect the start of radiation irradiation, the power of the battery 40 of the radiographic image capturing apparatus 1 will be consumed wastefully if the sub-control means 23 or the like is activated as it is.

  For this reason, in the present embodiment, the sub-control unit 23 receives the radiation when a predetermined time elapses after the sub-control unit 23 is started by turning on the power of the radiographic imaging device 1 or the like. The power supply of the image capturing device 1 is turned off.

  The sub-control unit 23 receives an OFF signal from the power switch 36 when the operator presses the power switch 36 of the radiographic imaging apparatus 1 or from an external device via the connected antenna device 39. The radiographic imaging apparatus 1 is also turned off when the operator intentionally turns off the radiographic imaging apparatus 1, such as when an off signal is received. Note that, when configured to receive an off signal from an external device via the antenna device 39, the sub-control means 23 is configured to also activate the antenna device 39.

  Furthermore, when the sub-control unit 23 detects that the radiographic imaging device 1 is connected to a charger such as a cradle (not shown) and the connection terminal 44 (see FIG. 7) of the battery 40 is connected to the charger, the radiographic image is detected. The imaging apparatus 1 is turned off and both the main control means 22 and the sub control means 23 are stopped. With this configuration, it is possible to prevent wasteful power consumption. In some cases, the radiographic imaging apparatus 1 is connected to a cable or the like, and radiographic imaging is performed while charging. In such a case, the radiographic imaging apparatus 1 is not turned off and the main control unit 22 is connected. Any of the sub-control means 23 is activated.

  In addition, when radiographic imaging is performed using the radiographic imaging apparatus 1 even though the remaining capacity of the battery 40 of the radiographic imaging apparatus 1 is small, a process of reading image data from each radiation detection element 7 or the like In the end, there is a case in which another radiographic imaging apparatus must be used to perform radiographic imaging again.

  However, this increases the exposure dose received by the patient and increases the burden on the patient. Therefore, the sub-control unit 23 checks the remaining capacity of the connected battery 40, and the remaining capacity of the battery 40 reads out image data from each radiation detection element 7 in the radiographic image capturing at least once, and stores it in the storage unit 43. The radiographic imaging apparatus 1 is turned off when a value greater than the capacity necessary for storage falls below a predetermined value set in advance.

  If comprised in this way, it will become possible to prevent that the exposure dose which a patient receives increases, and to prevent that the burden concerning a patient becomes large exactly.

  As will be described later, the main control unit 22 may read the image data from each radiation detection element 7 and store it in the storage unit 43, and then transmit the image data to an external device via the antenna device 39. Therefore, the above-mentioned predetermined value is a capacity necessary for not only reading out image data from each radiation detecting element 7 and storing it in the storage means 43 in one radiographic imaging, but also transmitting image data. It is also possible to configure to set the above values in advance.

  In addition, when the radiographic imaging apparatus 1 is turned off as described above, for example, the radiographic imaging apparatus 1 is notified with a buzzer or the like in order to reliably notify the operator that the power is off. It is also possible to configure so that the notification means is sounded when the sub-control means 23 turns off the power of the radiographic image capturing apparatus 1.

  On the other hand, in the present embodiment, as described above, an off signal from an external device or an off signal from the power switch 36 is received, or a predetermined time elapses after the sub-control means 23 itself is activated. If not, the sub-control unit 23 is in a state where either the sub-control unit 23 or the main control unit 22 is operating until the remaining capacity of the battery 40 is equal to or less than the predetermined value described above. Therefore, the power of the radiographic image capturing apparatus 1 is not turned off.

  With this configuration, even when the operator forgets to turn on the power of the radiographic imaging apparatus 1 and the radiographic imaging apparatus 1 is used for radiographic imaging, the sub-control unit 23 is activated with low power consumption. Thus, it is possible to detect the start of radiation irradiation and the like based on the voltage value V corresponding to the current detected by the current detection means 41 and to activate the main control means 22 accurately.

  In the case where it is not configured as described above, the radiation image capturing apparatus 1 recognizes that the operator has forgotten to turn on after irradiating the patient as a subject with radiation using the radiation image capturing apparatus 1 that has forgotten to turn on the power. It is necessary to turn on the power of 1 again and perform radiographic imaging again. However, if configured as described above, it is not necessary to perform radiographic imaging again, and the patient as a subject is irradiated with radiation many times. Therefore, it is possible to prevent the patient from receiving a heavy burden by increasing the exposure dose received by the patient.

  When the main control unit 22 receives the activation signal from the sub-control unit 23 and starts up, the main control unit 22 controls the scanning driving unit 15 and the readout circuit 17 to release charges from each radiation detection element 7 and read out the image data. Read processing is performed. At this time, as described above, the sub-control means 23 stops its own activation, or stops its activation by a stop signal from the activated main control means 22.

  As described above, when the sub-control unit 23 is configured to detect until the end of radiation irradiation (see time t3 in FIG. 10B), the main control unit 22 is activated. The reading process can be started immediately.

  However, if the sub-control unit 23 is configured to detect only the start of radiation irradiation and activate the main control unit 22, the main control unit 22 starts the reading process before the end of radiation irradiation. It is necessary to configure so that it does not. Therefore, in that case, after detecting the start of radiation irradiation, it is possible to configure the main control means 22 to start after a predetermined time when the irradiation is expected to end.

  Further, for example, the current detection unit 41 and the main control unit 22 are connected, and the main control unit 22 itself ends radiation irradiation based on the output voltage value V (see time t3 in FIG. 10B). ) May be detected.

  Further, before the sub-control unit 23 stops activation, information such as the radiation irradiation start time (time t1) is transmitted from the sub-control unit 23 to the main control unit 22 activated, and the main control unit 22 It is also possible to configure so that the reading process is started after a predetermined time has elapsed since the start of irradiation.

  When the main control unit 22 performs a process of reading image data from each radiation detection element 7, the current detection unit 41 and the feedback circuit 45 do not need to be operating. Therefore, before the sub-control unit 23 stops the activation, or the activated main control unit 22 switches the switch 45c of the feedback circuit 45 and connects the connection 10 of the bias line 9 and the bias power supply 14 via the switch 45c. In addition to the direct connection, the supply of power from the power supply means 46 to the differential amplifier 41c of the current detection means 41 and the amplifier 45b of the feedback circuit 45 is stopped to stop the operation of the current detection means 41 and the feedback circuit 45. It has become.

  Contrary to the above, when the main control means 22 stops starting and the sub control means 23 starts, before the main control means 22 stops starting, or the activated sub control means 23 The switch 45c of the feedback circuit 45 is switched to connect the inverting input terminal of the amplifier 45b of the feedback circuit 45 to the connection 10 of the bias line 9, and to connect the non-inverting input terminal to the bias power source 14. As a result, the supply of power from the power supply means 46 to the differential amplifier 41c of the current detection means 41 and the amplifier 45b of the feedback circuit 45 is resumed to operate the current detection means 41 and the feedback circuit 45.

  As described above, the main control unit 22 is connected to the bias power source 14, the scan driving unit 15, the readout circuit 17, the battery 40, and the like. At the time of reading image data from each radiation detection element 7, the main control means 22 controls the bias power supply 14 to vary the bias voltage applied to each radiation detection element 7 from the bias power supply 14 as necessary, or to scan. A pulse signal for switching the voltage applied to the gate electrode 8g of each TFT 8 between the on-voltage and the off-voltage from the driving means 15 via each scanning line 5 is transmitted.

  Further, the main control means 22 controls on / off of the charge reset switch 18c of the amplifier circuit 18 of the readout circuit 17, or sends a pulse signal to the correlated double sampling circuit 19 to turn on the sample hold function. Various processes such as controlling off / off are executed. When the main control means 22 is activated, power is supplied to the readout circuit 17 not only to the amplifier circuit 18 but also to the functional units such as the correlated double sampling circuit 19. The function unit is activated.

  When the main control means 22 reads out the image data from each radiation detection element 7 and saves it in the storage means 43 as described above, the main control means 22 is predetermined depending on whether the radiographic imaging is single imaging or continuous imaging. Is supposed to perform the operation. In the present embodiment, the radiation image capturing apparatus 1 irradiates the radiation image continuously to the same subject through the antenna device 39 or manually by the operator. The main control means 22 can perform a predetermined operation depending on whether or not the information is input.

  When the radiographic image capturing is a single image capturing, the main control unit 22 stores the image data obtained by completing the reading process in the storage unit 43 and also transmits the image to the external device via the antenna device 39. Send data. As described above, when the radiographic image capturing apparatus 1 is formed integrally with the support base, or is used by being loaded into the bucky apparatus, the support unit or the bucky apparatus is used. It is also possible to transmit image data to an external device by a wired system using a cable or the like.

  In the present embodiment, when the transmission of the image data to the external apparatus is completed, the main control unit 22 activates the sub control unit 23 and stops the activation itself, or from the activated sub control unit 23. The start is stopped by the stop signal. At that time, necessary information is transmitted from the main control means 22 to the sub-control means 23.

  Then, returning to the state when the power of the radiographic image capturing apparatus 1 is turned on as described above, the activated sub-control unit 23 performs reset processing of each radiation detection element 7 and sets the current detection unit 41 and the like. It is activated to continue monitoring whether or not radiation irradiation has started.

  With this configuration, it is possible to set the main control unit 22 that consumes relatively large power to the sleep state and to monitor the start of radiation irradiation by the sub control unit 23 that operates with low power consumption. Therefore, it is possible to suppress the power consumption of the battery 40.

  When the radiographic imaging is continuous imaging, the main control unit 22 activates the sub-control unit 23 with the image data that has been read out being stored in the storage unit 43, and stops the activation itself. Alternatively, the activation is stopped by a stop signal from the activated sub-control means 23.

  Then, when the sub-control means 23 performs reset processing of each radiation detection element 7 and detects the start or end of radiation irradiation based on the output from the activated current detection means 41, the main control means 22 is activated. Then, the activation of the sub-control means 23 is stopped. In the present embodiment, the activation of the main control unit 22 and the sub control unit 23 as described above and the stop of the activation are repeated until the continuous shooting is completed.

  When the radiographic image capturing is continuous imaging, the activated main control unit 22 also performs detection processing such as reset processing of each radiation detection element 7 and start of radiation irradiation performed continuously, and the like. It is also possible to configure the main control means 22 to perform all processing from the end of shooting until the end of transmission of all image data. Even in the case of such a configuration, at least at the stage where the continuous shooting is finished, the main control unit 22 activates the sub-control unit 23 and stops the activation itself, or the activated sub-control unit 23. The activation is stopped by a stop signal from

  As described above, according to the radiographic imaging device 1 according to the present embodiment, various functional units are operated to perform processing such as image data reading processing and image data transmission from each radiation detection element 7. Processes that need to be performed are accurately performed by the main control means 22 that consumes a large amount of power, and only specific function units are monitored, such as reset processing of other radiation detection elements 7 and monitoring of the start of radiation irradiation. The processing that can be executed if it is activated is configured to activate only the necessary functional units, and to be performed by the sub-control unit 23 that consumes less power than the main control unit 22.

  For this reason, it is possible to detect the start of radiation irradiation and the like by the radiation image capturing apparatus 1 itself regardless of an external apparatus such as a radiation irradiation apparatus. At the same time, power is supplied only to functional units necessary for each process such as detection of current flowing in the apparatus such as the bias line 9 and the like, reading process of image data, and transmission of image data as radiation irradiation starts. In addition, since power is not supplied to functional units that are not necessary for each process, it is possible to appropriately suppress wasteful power consumption.

  In addition, since power is not consumed unnecessarily, in the portable radiographic imaging apparatus 1 with the built-in battery 40, consumption of the battery 40 is suppressed, and more radiographic imaging can be performed with one charge. Thus, the use efficiency of the radiation image capturing apparatus 1 can be improved.

  In addition, since the consumption of the battery 40 is suppressed, it is possible to accurately avoid the re-execution of the radiographic image capturing due to the consumption of the battery 40. Therefore, it is possible to accurately prevent the exposure dose received by the patient as the subject from increasing and the burden on the patient from increasing.

(Other embodiments)
In the present embodiment shown in FIG. 8, the current detection means 41 is provided in the connection portion between the connection 10 of the bias line 9 and the bias power supply 14, and the bias power supply 14 and the radiation detection element are accompanied with the start of radiation irradiation. The current detection means 41 is not necessarily connected to the bias line 9 as long as the current flowing through the apparatus can be detected with the start of radiation irradiation. It is not necessary to provide at the connection portion between the connection 10 and the bias power source 14, and it is also possible to provide at other positions.

  For example, when radiation irradiation is started, a current flows between the power supply unit 42 and the amplifier circuit 18 in the readout circuit 17. However, the current detection unit 41 may be configured to detect the current. It is. This is illustrated in FIG. FIG. 11 shows an example of a radiographic image capturing apparatus according to another embodiment. In another embodiment, the current detection means 41 is provided on a wiring connecting the power supply unit 42 and the operational amplifier 18a of the amplifier circuit 18.

  In FIG. 11, the feedback circuit is not shown. However, as with the feedback circuit 45 shown in FIG. 9, a feedback circuit may be provided between the current detection means 41 and the operational amplifier 18a. Good. Further, when no feedback circuit is provided as shown in FIG. 11, power is supplied from the power supply means 46 to the differential amplifier 41 when detecting the current flowing in the wiring connecting the power supply unit 42 and the amplifier circuit 18. When the switch 41d is turned off and no current is detected, the supply of power from the power supply means 46 to the differential amplifier 41 is stopped, the switch 41d is turned on, and both terminals of the resistor 41a are turned on. They are short-circuited.

  When the current detection means 41 is provided at the connection portion between the connection 10 of the bias line 9 and the bias power supply 14 as in the present embodiment shown in FIG. 8, noise generated by the current detection means 41 is generated in each radiation detection element 7. In addition, since the noise is amplified by the amplifier circuit 18, relatively large noise may be superimposed on the image data finally read from each radiation detection element 7.

  On the other hand, the operational amplifier 18a of the amplifier circuit 18 is generally configured so that fluctuations in the power supply voltage are not easily transmitted to the output due to the PSRR (Power Supply Rejection Ratio) characteristic, so that noise from the power supply section 42 is reduced and output. Is done.

  Therefore, when the current detection unit 41 is provided between the power supply unit 42 and the amplifier circuit 18 as in the other embodiments, the noise generated in the current detection unit 41 is also caused by the PSRR characteristics of the amplifier circuit 18. Therefore, it is possible to further reduce noise superimposed on the image data read from each radiation detection element 7 in the end.

  The current detection means 41 accurately detects a current flowing between the bias power supply 14 and each radiation detection element 7 or between the power supply unit 42 and the amplifier circuit 18 or a voltage value V corresponding thereto. As long as it can be used, the configuration is not limited to the configuration illustrated in FIGS. 9 and 11, for example, and an appropriate configuration may be employed.

  Further, in the present embodiment, in order to enable imaging even when the operator forgets to turn on the power of the radiographic imaging apparatus 1 and uses the radiographic imaging apparatus 1 for radiographic imaging. The case has been described in which the radiographic imaging apparatus 1 is configured not to be turned off until the remaining capacity of the battery 40 is equal to or less than the predetermined value described above.

  In order to make this more thorough, as another embodiment, until the remaining capacity of the battery 40 becomes equal to or less than the predetermined value described above, the operator transmits an off signal transmitted from the external device, or the radiographic imaging device by the operator Even when one power switch 36 is operated and an off signal is received from the power switch 36, the radiographic imaging apparatus 1 can be configured not to be turned off.

  According to this configuration, even when the operator forgets to turn on the power of the radiographic imaging apparatus 1 and performs radiographic imaging using the radiographic imaging apparatus 1, radiographic imaging can be surely performed. Therefore, it is possible to reliably prevent an increase in the exposure dose received by the patient by performing radiographic imaging again and an increase in the burden on the patient.

  However, if the radiographic image capturing apparatus 1 is always in the above mode (hereinafter referred to as the first mode), the power consumption of the battery 40 increases and radiographic images are captured per charge. The number of possible sheets is reduced.

  Therefore, as another embodiment, when the radiographic imaging apparatus 1 receives the first mode as described above and at least an off signal from an external apparatus, or when the power switch 36 of the radiographic imaging apparatus 1 is pressed, the off signal Can be configured so that the operator can select a mode for turning off the power of the apparatus (hereinafter, the second mode).

  According to this configuration, the radiographic imaging apparatus 1 is used so that it can be taken even if the power of the radiographic imaging apparatus 1 is forgotten to be turned on, or according to the operator's intention to increase the number of images that can be taken per charge. Thus, the mode of the radiation image capturing apparatus 1 can be selected, and the user-friendliness can be improved.

DESCRIPTION OF SYMBOLS 1 Radiographic imaging apparatus 5 Scanning line 6 Signal line 7 Radiation detection element 8 TFT (switch means)
DESCRIPTION OF SYMBOLS 14 Bias power supply 15 Scan drive means 17 Reading circuit 18 Amplification circuit 22 Main control means 23 Sub control means 36 Power switch 40 Battery 41 Current detection means 42 Power supply part r area V Voltage value (voltage value equivalent to current)

Claims (11)

A plurality of scanning lines and a plurality of signal lines arranged so as to intersect with each other; a plurality of radiation detecting elements arranged in a two-dimensional manner in each region partitioned by the plurality of scanning lines and the plurality of signal lines; ,
Switch means arranged for each radiation detection element, holding the charge generated in the radiation detection element in the off state, and discharging the charge from the radiation detection element in the on state;
A readout circuit that converts the electric charge emitted from the radiation detection element into a voltage and reads it as image data;
Scanning drive means for switching between the OFF state and the ON state of each switch means via the scanning line;
In a radiographic imaging device comprising:
Current detecting means for detecting a current flowing in the apparatus with radiation,
Sub-control means for detecting the start and / or end of radiation irradiation based on the value of the current detected by the current detection means;
Main control means for controlling the scanning drive means and the readout circuit to perform the readout process of the image data from the radiation detection element;
With
The sub control means has less power consumption than the main control means,
When the start and / or end of radiation irradiation is detected based on the value of the current detected by the current detection means, the main control means is activated and the sub-control means is deactivated. A radiographic imaging device.   The sub-control unit controls the scan driving unit to turn off the switch units when detecting the start of radiation irradiation based on the value of the current detected by the current detection unit. The radiographic image capturing apparatus according to claim 1. When the sub-control unit detects the start and / or end of radiation irradiation based on the value of the current detected by the current detection unit,
Activating the main control means,
The radiographic imaging apparatus according to claim 1, wherein the radiographic imaging apparatus stops the activation by itself or stops the activation by a stop signal from the activated main control unit.   When the main control means completes the reading process of the image data from the radiation detection element, the main control means activates the sub-control means, stops the activation itself, or a stop signal from the activated sub-control means The radiographic imaging apparatus according to claim 1, wherein the activation is stopped by the operation.   When the main control means completes the transmission of the image data to the external device, the main control means activates the sub-control means, stops itself, or activates according to a stop signal from the activated sub-control means. The radiographic image capturing apparatus according to claim 1, wherein the radiographic image capturing apparatus is stopped.   6. The main control unit and the sub control unit are set in a sleep state in which only a start signal for instructing start can be received in a stop state of start. The radiographic imaging apparatus described in 1. It has a built-in battery that supplies power to each function unit,
In the sub-control unit, the remaining capacity of the battery is equal to or less than a predetermined value set to a value greater than or equal to a capacity necessary for performing a process of reading image data from each radiation detection element in at least one radiation image capturing. The radiographic imaging apparatus according to any one of claims 1 to 6, wherein the power of the apparatus is not turned off until the time becomes. It has a built-in battery that supplies power to each function unit,
When the sub-control unit receives an off signal from an external device, when a predetermined time elapses after the sub-control unit is activated, when a power switch is pressed and an off signal is received, Alternatively, when the remaining capacity of the battery becomes equal to or less than a predetermined value set to a value greater than or equal to the capacity necessary for performing image data reading processing from each radiation detection element in at least one radiation image capturing. The radiographic imaging apparatus according to claim 1, wherein the apparatus is turned off. It has a built-in battery that supplies power to each function unit,
Even when an off signal is received from an external device or when a power switch is pressed to receive an off signal, the remaining capacity of the battery is image data from each radiation detection element in radiographic imaging at least once. The first mode in which the power of the apparatus is not turned off until the predetermined value set to a value greater than or equal to the capacity required for performing the reading process, and when the off signal from the external apparatus is received or the power switch is pressed The radiographic image according to any one of claims 1 to 6, wherein the radiographic image is configured to be able to select a second mode in which the apparatus is turned off when an off signal is received. Shooting device. A bias power supply for applying a reverse bias voltage to the radiation detection element;
10. The current detection unit detects a current flowing between the bias power source and the radiation detection element in accordance with the start of radiation irradiation. 10. Radiographic imaging device. The readout circuit has an amplification circuit that amplifies a voltage obtained by converting the electric charge emitted from the radiation detection element,
A power supply unit for supplying a voltage to the amplifier circuit;
The said current detection means detects the electric current which flows between the said power supply part and the said amplifier circuit with the start of irradiation of a radiation, The Claim 1 characterized by the above-mentioned. Radiographic imaging device.