JP2012164745A - Radiation detection device - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a radiation detection device capable of accurately detecting radiation rays in a short time.SOLUTION: A radiation detection element 10 comprises a plurality of photo diodes 12A uniformly arranged in a predefined radiation detection region, detecting radiation rays radiated on a subject, and outputting electric signals for an image according to the detected radiation rays to a signal wiring via a switching element; and a plurality of photo diodes 12B, which are radiation detection elements formed by splitting one part of the radiation detection element for an image, arranged at a predefined pattern, detect the radiation rays radiated to the subject, and directly output electric signals for a monitor according to the detected radiation rays to the wiring.

Description

  The present invention relates to a radiation detection apparatus, and more particularly to a radiation detection apparatus that detects a radiation image of irradiated radiation.

  2. Description of the Related Art In recent years, a radiographic imaging apparatus using a radiation detection element such as an FPD (flat panel detector) that can arrange an X-ray sensitive layer on a TFT (Thin film transistor) active matrix substrate and convert X-ray information directly into digital data. It has been put into practical use. Compared with conventional imaging plates, this FPD has the advantage that images can be confirmed instantly and moving images can be confirmed, and is rapidly spreading.

  Various types of radiation detection elements of this type have been proposed. For example, a direct conversion method in which radiation is directly converted into electric charges in a semiconductor layer and stored, or radiation is once converted into CsI: Tl, GOS (Gd2O2S). There is an indirect conversion method in which the light is converted into light by a scintillator such as Tb), and the converted light is converted into electric charges in a semiconductor layer and accumulated.

  By the way, a general radiographic imaging apparatus requires calibration of radiation exposure timing between the radiographic imaging apparatus and the radiation source. Since it differs depending on the combination of the radiation image capturing apparatus and the radiation source, the calibration work performed at the time of installation is extremely troublesome. In particular, in the case of a portable radiographic imaging apparatus, a plurality of types of radiation sources are often used, and the calibration work is a heavy work load when used in an emergency application. It is demanded to eliminate.

  Conventionally, a signal of one pixel or several pixels in a specific area has been used for radiation detection, but in this case, a region that can be used for determination of radiation detection is narrow and a signal value is small.

  And in radiography, it is necessary to irradiate only a small area with a small dose of radiation to reduce the exposure dose, but the signal that can be used for radiation detection is only a weak signal that has passed through the human body, It becomes difficult to detect radiation reliably. Further, even when a blank portion that does not transmit through the human body and is irradiated with radiation exists in the radiation irradiation region, radiation cannot be detected unless there is a radiation detection pixel in that region.

  Patent Document 1 discloses a radiation imaging apparatus that enables nondestructive readout of signal charges of a photoelectric conversion element by adopting a source follower type structure. In this apparatus, a signal charge is read out line by line to determine the start of X-ray irradiation, and a reset operation is performed to read out a dark current.

  Patent Document 2 discloses a radiation detection apparatus including a dedicated element for X-ray monitoring above a gate wiring. In this apparatus, a dedicated element for X-ray monitoring is arranged in a specific area and connected to a dedicated wiring, and used for AEC (automatic exposure control).

  Patent Document 3 discloses a radiation imaging apparatus in which a monitor photoelectric conversion element for monitoring a radiation dose is arranged in the vicinity of an imaging photoelectric conversion element that converts radiation into an image.

JP 2003-126072 A JP 2005-147958 A JP 2004-228516 A

  However, in the technique described in Patent Document 1, since only the line on which reading is performed is involved in the detection of X-rays, a signal intensity capable of X-ray detection cannot be obtained in a region where there are no missing portions. There was a problem.

  Further, Patent Document 1 discloses that pixel values of a plurality of pixels are summed, but since a switching element is provided, switching noise (feedthrough noise) is also summed simply by summing, There is also a problem that only up to about ten pixels can be added (the detection unit is saturated by switching noise).

  Moreover, in the technique described in Patent Document 2, since the dedicated element for X-ray monitoring is arranged only in a specific area, it is necessary to extend the integration time in order to obtain a signal sufficient for radiation detection. In addition, there is a problem that radiation cannot be detected in the case of photographing with a narrow irradiation field.

  In addition, since the dedicated element for X-ray monitoring is arranged above the gate wiring, there is a problem that parasitic capacitance increases.

  Furthermore, since automatic surface inspection during TFT manufacturing cannot be performed, there is a problem in that manufacturing yield decreases.

  That is, in TFT manufacturing, automatic surface inspection is performed for each layer in order to inspect foreign objects, short circuits, and disconnections. In this inspection, whether or not the circuit has the same repeated pattern is used as a criterion. Yes. In the technique described in Patent Document 2, since only a part of a specific area of the pixel area has a pattern different from other areas, this is detected as a foreign substance, and a normal foreign substance inspection or the like may be performed. There was also a problem of being unable to do so.

  In the technique described in Patent Document 3, since a TFT, that is, a switching element is connected to the monitor photoelectric conversion element, the pixel values of a plurality of pixels are added together as in the technique described in Patent Document 1. In this case, there is a problem that the switching noise is also summed up simply by summing up, and only a few to ten pixels can be summed up.

  Furthermore, in the technique described in Patent Document 3, since the photoelectric conversion element for monitoring is arranged only in a specific area, a signal sufficient for detection of radiation is obtained as in the technique described in Patent Document 2. For this purpose, it is necessary to extend the integration time, and there is a problem that radiation cannot be detected in the case of imaging with the irradiation field narrowed down.

  Thus, conventionally, there has been a problem that it is difficult to obtain an S / N necessary for detecting radiation in a short time.

  The present invention has been made to solve the above-described problems, and an object of the present invention is to provide a radiation detection apparatus capable of accurately detecting radiation in a short time.

  In order to achieve the above object, the invention described in claim 1 is arranged uniformly in a predetermined radiation detection region, detects radiation applied to a subject, and switches an electrical signal for an image according to the detected radiation. A plurality of image radiation detection elements that are output to the signal wiring via the elements, and are arranged adjacent to each of the plurality of image radiation detection elements, and are uniformly and predetermined in the predetermined radiation detection region. A plurality of radiation detecting elements for monitoring, which are arranged in a repeated pattern, detect radiation applied to the subject, and output a monitor electrical signal corresponding to the detected radiation directly to the wiring. Yes.

  According to the present invention, the monitor radiation detecting elements are arranged adjacent to each of the image radiation detecting elements, and are arranged in the predetermined radiation detection region uniformly and in a predetermined repeating pattern, and are detected. The monitoring electrical signal corresponding to the emitted radiation is directly output to the wiring. For this reason, signals from a plurality of radiation detecting elements for monitoring can be integrated without being affected by switching noise or the like, and radiation can be detected accurately in a short time. Further, by arranging the monitor radiation detecting elements in a predetermined repeating pattern, an automatic surface inspection can be performed at the time of manufacturing the TFT, and a decrease in yield can be suppressed. The “radiation detection region” refers to a region where both the image radiation detection element and the monitor radiation detection element are arranged, and is not limited to the entire surface of the radiation detection apparatus. For example, a part of the radiation detection device, for example, a region excluding the peripheral portion of the radiation detection device may be used as a radiation detection region, and both the image radiation detection element and the monitor radiation detection element may be disposed in this region. . In this case, an image radiation detection element may be disposed at the peripheral edge of the radiation detection apparatus.

  In addition, as described in claim 2, the monitor radiation detection element may be arranged adjacent to each of all the image radiation detection elements. As a result, radiation can be detected with higher accuracy in a shorter time.

  According to a third aspect of the present invention, there is provided a monitor electrical signal detecting means for detecting the monitor electrical signal output from the monitor radiation detecting element, wherein the wiring includes the monitor radiation detecting element and the monitor radiation detecting element. It is good also as a structure which is an exclusive wiring which connects with the electrical signal detection means for a monitor. As a result, radiation can be detected regardless of reset driving for removing dark current components.

  According to a fourth aspect of the present invention, the wiring may be the signal wiring. Thereby, the circuit configuration can be simplified.

  Further, as described in claim 5, the adjacent radiation detecting elements for monitoring may be connected to one signal wiring. Thereby, the sensitivity of radiation detection per line can be doubled.

  Thus, according to the present invention, there is an excellent effect that radiation can be accurately detected in a short time.

It is a block diagram which shows the whole structure of the radiographic imaging apparatus which concerns on 1st Embodiment. It is a block diagram which shows the whole structure of the radiographic imaging apparatus which concerns on 1st Embodiment. It is a partial enlarged view of the radiation detection element concerning a 1st embodiment. It is a figure for demonstrating the sequence of a X-ray detection. It is a figure for demonstrating the sequence of a X-ray detection. It is an image figure for demonstrating X-ray irradiation. It is an image figure for demonstrating X-ray irradiation. It is a block diagram which shows the whole structure of the radiographic imaging apparatus which concerns on 2nd Embodiment. It is a partial enlarged view of the radiation detection element which concerns on 2nd Embodiment. It is a block diagram which shows the whole structure of the radiographic imaging apparatus which concerns on 3rd Embodiment. It is a partial enlarged view of the radiation detection element which concerns on 3rd Embodiment. It is a block diagram which shows the modification of the whole structure of a radiographic imaging apparatus. It is line sectional drawing of a radiation detection element.

  DESCRIPTION OF EMBODIMENTS Hereinafter, embodiments for carrying out the present invention will be described with reference to the drawings.

  In the present embodiment, a case will be described in which the present invention is applied to an indirect conversion type radiation detection apparatus 10 that once converts radiation such as X-rays into light and converts the converted light into electric charges.

  [First Embodiment]

  FIG. 1 shows an overall configuration of a radiographic image capturing apparatus 100 using the radiation detection apparatus 10 according to the first exemplary embodiment.

  As shown in the figure, a radiographic imaging apparatus 100 according to the present embodiment includes an indirect conversion type radiation detection apparatus 10. Note that a scintillator that converts radiation into light is omitted.

  The radiation detection apparatus 10 includes photodiodes 12A and 12B that generate light by receiving light, accumulate the generated charges, and a TFT switch 4 for reading out the charges accumulated in the photodiode 12A. A plurality of pixels 20 are arranged in a matrix in one direction and a crossing direction with respect to one direction. In the present embodiment, the photodiodes 12A and 12B are irradiated with light converted by a scintillator (not shown) to generate charges.

  The photodiode 12A functions as a radiation detection element for images, and the photodiode 12B functions as a radiation detection element for radiation monitoring. Note that the photodiodes 12A and 12B are arranged uniformly and in a predetermined repeating pattern in a predetermined radiation detection region. Here, the “radiation detection region” refers to a region where both the photodiodes 12 </ b> A and 12 </ b> B are arranged, and is not limited to the entire surface of the radiation detection device 10. For example, a part of the region of the radiation detection device 10, for example, a region excluding the peripheral portion of the radiation detection device 10 may be used as a radiation detection region, and both the photodiodes 12A and 12B may be arranged in this region. In this case, a photodiode 12A as an image radiation detection element may be arranged at the peripheral edge of the radiation detection apparatus.

  As described above, since each pixel includes the radiation monitor photodiode 12B in the radiation image capturing apparatus 100, a radiation monitor photo can be obtained without synchronizing with an X-ray source (not shown) that emits X-rays. By detecting the radiation with the diode 12B, the radiation image capturing apparatus 100 itself detects that the radiation has been emitted from the X-ray source, and can shift to image capturing.

  The radiation detection apparatus 10 includes a plurality of scanning wirings 101 for turning on / off the TFT switch 4 and a plurality of signal wirings 3 for reading out the charges accumulated in the photodiodes 12A and 12B on the substrate. And are provided so as to cross each other. In this embodiment, one signal wiring 3 is provided for each pixel column in one direction (column direction in FIG. 1), and one scanning wiring 101 is provided for each pixel column in the cross direction (row direction in FIG. 1). It is provided one by one.

  Each scanning wiring 101 is connected to the gate of the TFT switch 4 of each pixel 20 in the pixel column in one direction, and each signal wiring 3 is connected to the source of the TFT switch 4 in each pixel 20 in the crossing direction pixel column. It is connected.

  Further, the radiation detection apparatus 10 is provided with a common electrode wiring 25 in parallel with each signal wiring 3. One end and the other end of the common electrode wiring 25 are connected in parallel, and one end is connected to a bias circuit 110 that supplies a predetermined bias voltage. The photodiodes 12 </ b> A and 12 </ b> B are connected to the common electrode wiring 25, and a bias voltage is applied through the common electrode wiring 25.

  The anode side of the photodiode 12A is connected to the signal wiring 3 through the TFT switch 4, and the cathode side is connected to the common electrode wiring 25. On the other hand, the anode side of the photodiode 12 </ b> B is directly connected to the signal wiring 3, and the cathode side is connected to the common electrode wiring 25. In the present embodiment, the photodiodes 12A and 12B are PIN type photodiodes, but the present invention is not limited to this, and MIS type diodes and NIP type diodes may be used.

  A control signal for switching each TFT switch 4 flows through the scanning wiring 101. As described above, when the control signal flows to each scanning wiring 101, each TFT switch 4 is switched.

  An electric signal corresponding to the electric charge accumulated in each pixel 20 flows through the signal wiring 3 in accordance with the switching state of the TFT switch 4 of each pixel 20. More specifically, each of the signal wirings 3 has an electric power corresponding to the amount of charge accumulated in the photodiode 12A when any TFT switch 4 of the pixel 20 connected to the signal wiring 3 is turned on. A signal flows. Since the TFT switch 4 is not connected to the photodiode 12B, an electrical signal corresponding to the accumulated charge amount flows through the signal wiring 3 as it is.

  Each signal wiring 3 is connected to a signal circuit 105 that detects an electrical signal flowing out to each signal wiring 3. Further, each scanning wiring 101 is connected to a driving circuit 104 that outputs a control signal (scanning signal) for turning on / off the TFT switch 4 to each scanning wiring 101.

  The signal circuit 105 incorporates an amplification circuit for amplifying an input electric signal for each signal wiring 3. In the signal circuit 105, an electric signal input from each signal wiring 3 is amplified by an amplifier circuit and converted into digital data.

  The signal circuit 105 and the drive circuit 104 perform predetermined processing such as noise removal on the digital data converted by the signal circuit 105 and output a control signal indicating signal detection timing to the signal circuit 105. A control unit 106 that outputs a control signal indicating the output timing of the scan signal is connected to the drive circuit 104.

  2 is a plan view showing the shape of the photodiodes 12A and 12B, and FIG. 3 is an enlarged plan view of one pixel 20. As shown in FIG. 2 and 3, the scintillator that converts radiation into light is omitted.

  As shown in FIGS. 2 and 3, the photodiode 12 </ b> B is formed in a part of the rectangular pixel 20 (upper left corner in FIG. 2). Conventionally, the entire rectangular pixel 20 is usually a single photodiode, but in this embodiment, a part of the rectangular photodiode is divided and the divided photodiode is used for radiation monitoring. It is said. In the present embodiment, the pixel is a rectangular pixel, but it may be a polygon.

  If the area of the radiation monitoring photodiode 12B is too large, the area of the image photodiode 12A is reduced, which affects the image quality. Therefore, it is preferable that the ratio of the area of the photodiode 12B to the pixel 20 is such that the image quality is within an allowable range, for example, about several percent to 10% of the entire pixel 20. In the present embodiment, the position of the photodiode 12B is the upper left corner of the pixel 20, and the shape is rectangular. However, the position and shape are not particularly limited.

  An electric signal corresponding to the charge accumulated in the monitoring photodiode 12 </ b> B directly connected to each signal wiring 3 is output to each signal wiring 3. Therefore, the signal circuit 105 is integrated with the charges accumulated in the plurality of monitoring photodiodes 12B (four in FIG. 1 and FIG. 2 are actually thousands) connected to each signal wiring 3. The electrical signal is output. That is, electrical signals accumulated in thousands of photodiodes 12B are binned and output to the signal circuit 105.

  In the signal circuit 105, the value of the electric signal output from each signal wiring 3 is compared with a predetermined threshold value, and the value of the electric signal output from any N (N ≧ 1) signal wirings 3 is determined. If the threshold value is exceeded, it is determined that X-rays are emitted from an X-ray source (not shown). Here, N can be appropriately set based on imaging conditions such as an X-ray irradiation dose, sensitivity of the X-ray detection element, and the like. Note that the threshold value is set to a value that can reliably determine that radiation has been emitted from the X-ray source if the value of the electric signal output from the signal wiring 3 is equal to or greater than this value. In the signal circuit 105, the values of the electrical signals from all the signal wirings 3 may be added, and this may be compared with a threshold value to determine whether or not X-rays have been emitted.

  FIG. 4 shows the X-ray dose emitted from an X-ray source (not shown) from the X-ray detection mode to the image accumulation mode and the image readout mode, and the radiation detected by the radiation detection device 10 (X-ray detection element). The X-ray dose of is shown schematically. As shown in the figure, first, in the X-ray detection mode, when radiation is irradiated from an X-ray source (not shown), the X-ray dose gradually rises and X-rays detected by the radiation detection device 10 are detected. The dose also increases gradually.

  Here, the photodiode accumulates electric charge even if it is not irradiated with X-rays, and this becomes a so-called dark current component. For this reason, in the X-ray detection mode, the drive circuit 104 outputs a control signal to the scanning wiring 101 to output the charge accumulated in each photodiode to the signal wiring 3, and the signal circuit 105 is incorporated. Reset driving is periodically performed to remove the dark current component by resetting the amplifier circuit. When X-rays are detected, the reset driving is stopped and the image accumulation mode is entered.

  Although it is necessary to detect radiation in a short time between the reset driving, the S / N ratio of the weak signal is as small as about 0.01 in the conventional integration time during the general reset driving. Therefore, in order to reliably perform X-ray detection, it is necessary to execute at least one of the integration time of 100 times or more, the addition of signals of 100 pixels or more, and the noise of 1/100 or less.

  Further, X-rays that are transmitted through the human body in the X-ray detection mode (portions indicated by hatching in FIG. 5) are lost because they are not used in the image. The time during which this loss occurs is preferably as short as possible.

  On the other hand, in the present embodiment, the charges accumulated in the thousands of photodiodes 12B connected to one signal wiring 3 are output to the integrated signal circuit 105, so the accuracy is reduced in a short time. X-rays can be detected.

  In addition, as shown in FIG. 6, for example, when the monitoring photodiode 52 is provided only in a very specific area with respect to the radiation detection element 50 as in the prior art, a part of the human body, for example, When the X-ray irradiation range 56 is limited around the lumbar vertebra 54, the photodiode 52 does not exist in the blank portion 58 where the X-ray is irradiated without passing through the human body. In FIG. 6, X-rays can be detected by the photodiode 52 at the center. However, since the X-rays pass through the human body, the intensity is very small, and it is difficult to accurately detect that the X-rays have been irradiated. is there.

  Furthermore, as shown in FIG. 7, when the X-ray irradiation range 56 is set around the knee portion of the human body, the photodiode 52 may not exist at all in that range. In this case, even if X-rays are irradiated, the X-rays cannot be detected by the radiation detection element 50, and imaging cannot be performed.

  On the other hand, in the present embodiment, as shown in FIGS. 1 and 2, a radiation monitor photodiode 12B is provided in all pixels. For this reason, even when a part of the human body is within the radiation irradiation range, the probability that the photodiode 12B exists in the blank portion where X-rays are irradiated without passing through the human body is increased. Further, as described above, even when the number of photodiodes 12B existing in the bare portion is small, as described above, the signal circuit in which charges accumulated in thousands of photodiodes 12B connected to one signal wiring 3 are integrated. Therefore, the S / N ratio can be improved, and X-rays can be detected accurately and in a short time.

  Here, for example, if the area of the photodiode 12B is 5% of the total area of one pixel and the number of pixels in one column is 3000 pixels, the signal intensity S of a signal output to one signal wiring 3 is expressed by the following equation: It is represented by

S = 0.05 × 3000 = 150

  Moreover, since the intensity of the X-rays in the unexposed portion is about 10 to 100 times that of the X-rays transmitted through the human body, the signal intensity S is further about 10 to 100 times higher than the above value. Thus, X-rays can be detected in a short time.

  In the present embodiment, the monitoring photodiode 12B is directly connected to the signal wiring 3 without a switching element. For this reason, switching noise is not added, and X-rays can be detected with high accuracy.

  Further, since the radiation monitoring photodiodes 12B are provided in all the pixels, the circuit pattern is uniform over the entire surface. Thereby, it can prevent that it determines with abnormality in the automatic surface inspection which determines whether the circuit is the same repeating pattern.

  Then, when the image accumulation mode ends, the mode shifts to the image reading mode. Transition to the image readout mode may be such that the period of the image accumulation mode is set in advance and the transition to the image readout mode is made after a certain period of time has elapsed, or X-ray irradiation is performed using the monitor photodiode 12B. It is also possible to determine the end and shift from the image accumulation mode to the image reading mode.

  When determining the end of X-ray irradiation, the X-ray dose during the image accumulation mode period is detected by the monitoring photodiode 12B, and the value of the electrical signal output from each signal wiring 3 by the signal circuit 105 is determined in advance. Each of the determined threshold values is compared, and if the value of the electric signal output from any N (N ≧ 1) signal wirings 3 is equal to or less than the threshold value, it is determined that the X-ray irradiation has ended. . Here, N can be appropriately set based on imaging conditions such as an X-ray irradiation dose, sensitivity of the X-ray detection element, and the like.

  Note that the above X-ray irradiation end determination process can also be executed in the second and third embodiments described later.

  [Second Embodiment]

  Next, a second embodiment will be described.

  8 and 9 show a configuration of a radiation detection apparatus 10A according to the second exemplary embodiment. The same parts as those in the first embodiment are denoted by the same reference numerals, and detailed description thereof is omitted.

  As shown in FIGS. 8 and 9, the radiation detection apparatus 10 </ b> A is different from the radiation detection apparatus 10 described in the first embodiment because the anode side of the photodiode 12 </ b> B is directly connected to the signal wiring 3. Rather, it is connected to the X-ray detection circuit 122 via the dedicated wiring 120.

  The dedicated wirings 120 are connected to each other and connected to the X-ray detection circuit 122.

  As a result, the X-ray detection circuit 122 integrates electric charges accumulated in the monitoring photodiodes 12B of all the pixels, that is, electric signals obtained by integrating the charges accumulated in the photodiodes 12B for several thousand pixels × thousands of pixels. Therefore, the S / N ratio can be greatly improved, and radiation can be detected with high accuracy in a short time.

  Here, for example, assuming that the area of the photodiode 12B is 5% of the total area of one pixel and the number of pixels in one vertical column and one horizontal column is 3000 pixels, a signal signal output to the X-ray detection circuit 122 The strength S is expressed by the following formula.

S = 0.05 × 3000 × 3000 = 450,000

  Furthermore, since the intensity of the X-rays in the unexposed portion is about 10 to 100 times that of the X-rays transmitted through the human body as described above, the signal intensity S is 10 to 10 times higher than the above value. It becomes about 100 times, and X-rays can be detected in a shorter time.

  In the present embodiment, since the X-ray is detected by the dedicated X-ray detection circuit 122, radiation can be detected regardless of reset driving.

  [Third Embodiment]

  Next, a third embodiment will be described.

  10 and 11 show a configuration of a radiation detection apparatus 10B according to the third exemplary embodiment. The same parts as those in the first embodiment are denoted by the same reference numerals, and detailed description thereof is omitted.

  As shown in FIGS. 10 and 11, the radiation detection device 10B is different from the radiation detection device 10 described in the first embodiment in that one signal wiring 3 is provided with a photodiode 12B provided in an adjacent pixel. Are connected in common.

  As a result, the charge accumulated in the photodiodes 12B provided in the adjacent two columns of pixels (thousands × two columns of pixels) is output to one signal wiring 3, and thus the sensitivity of radiation detection. Can be improved.

  As mentioned above, although this invention was demonstrated using the 1st-3rd embodiment, the technical scope of this invention is not limited to the range as described in each said embodiment. Various modifications or improvements can be added to the above-described embodiments without departing from the gist of the invention, and embodiments to which the modifications or improvements are added are also included in the technical scope of the present invention.

  For example, in each of the above embodiments, the case where the monitoring photodiodes 12B are provided in all the pixels has been described. However, the monitoring photodiodes 12B need not be provided in all the pixels, and the monitoring photodiodes 12B are arranged in the same repeating pattern. Just do it. For example, as shown in FIG. 12, when viewed in an area of 4 pixels of 2 × 2 pixels, two monitor photodiodes 12B are arranged obliquely, and this pattern is repeated every 4 pixels. Even in such a case, it is possible to prevent the automatic surface inspection for determining whether or not the circuit has the same repeated pattern from being determined as abnormal.

  In each of the above-described embodiments, the case where the present invention is applied to the indirect conversion type radiation detection apparatus 10 has been described. You may apply to. In this case, the sensor unit in the direct conversion method generates charges when irradiated with radiation.

  In each of the above embodiments, the case where the present invention is applied to the radiographic imaging apparatus 100 that detects an image by detecting X-rays has been described. However, the present invention is not limited to this, for example, The radiation to be detected may be any of X-rays, visible light, gamma rays, particle beams, and the like.

  In addition, the configuration of the radiographic image capturing apparatus 100 and the configuration of the radiation detection apparatus 10 described in the above embodiment are merely examples, and it is needless to say that the configuration can be appropriately changed without departing from the gist of the present invention.

3 Signal wiring 4 TFT switch (switching element)
10 Radiation Detection Device 12A Photodiode (Radiation Detection Element for Imaging)
12B Photodiode (radiation detection element for monitoring)
20 pixels 101 scanning wiring

Claims (5)

A plurality of image radiation detection elements that are uniformly arranged in a predetermined radiation detection region, detect radiation applied to a subject, and output an image electrical signal corresponding to the detected radiation to a signal wiring via a switching element When,
It is arranged adjacent to each of the plurality of image radiation detection elements, and is arranged uniformly and in a predetermined repeating pattern in the predetermined radiation detection region, and detects the radiation irradiated to the subject, A plurality of monitoring radiation detection elements that directly output electrical signals for monitoring corresponding to the detected radiation to the wiring;
A radiation detection apparatus comprising: The radiation detection apparatus according to claim 1, wherein the monitoring radiation detection element is disposed adjacent to each of the imaging radiation detection elements. A monitoring electrical signal detecting means for detecting the monitoring electrical signal output from the monitoring radiation detecting element; and the wiring is dedicated for connecting the monitoring radiation detecting element and the monitoring electrical signal detecting means The radiation detection apparatus according to claim 1, wherein the radiation detection apparatus is a wiring. The radiation detection apparatus according to claim 1, wherein the wiring is the signal wiring. The radiation detection apparatus according to claim 4, wherein the adjacent radiation detection elements for monitoring are connected to one signal wiring.

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