Abstract:
The present invention provides radiographic imaging elements that can obtain a radiographic image by irradiation with radiation of different energies at a single time, while suppressing positional misalignment. Namely, radiographic imaging elements are disposed layered on one face-side of a support substrate. A signal detection circuit and a scan signal control circuit are disposed on the opposite face-side of the support substrate, these circuits performing at least one of control of detection and/or signal processing of image signals in the respective radiographic imaging elements. The signal detection circuit and the scan signal control circuit are connected to the respective radiographic imaging elements by connection lines, enabling communication.

Description:
CROSS-REFERENCE TO RELATED APPLICATION 
       [0001]    This application claims priority under 35 USC 119 from Japanese Patent Application No. 2008-274606, filed on Oct. 24, 2008, the disclosure of which is incorporated by reference herein. 
       BACKGROUND OF THE INVENTION 
       [0002]    1. Field of the Invention 
         [0003]    The present invention relates to a radiographic imaging element. The present invention relates in particular to a radiographic imaging device that detects images representing irradiated radiation. 
         [0004]    2. Description of the Related Art 
         [0005]    Radiographic imaging devices using radiographic imaging elements such as FPDs (flat panel detectors), in which an X-ray sensitive layer is disposed on a TFT (thin film transistor) active matrix substrate and that can convert X-ray information directly into digital data, and the like, have been put into practice in recent years. Such radiographic imaging elements have the merit that, in comparison to with previous imaging plates, images can be more immediately checked and video images can also be checked. Consequently the introduction of radiographic imaging elements is proceeding rapidly. 
         [0006]    Various types for such radiographic imaging elements are proposed. For example, there is a direct-conversion-type radiographic imaging elements that converts radiation, such as X-rays, directly into charges in a semiconductor layer, and accumulates the charges. Moreover, there is also indirect-conversion-type radiographic imaging elements that once converts radiation into light at a scintillator (wavelength converter), such as CsI:Tl, GOS (Gd 2 O 2 S:Tb) or the like, then converts the converted light into charges in sensor portions, such as photodiodes or the like, and accumulates the charges. 
         [0007]    The following technique is known in the photographing of radiation images. By photographing the same region of a subject at different tube voltages, and carrying out image processing (hereinafter called “subtraction image processing”) that weights the radiation images obtained by the photographings at the respective tube voltages and computes the difference therebetween, a radiation image (hereinafter called “energy subtraction image”) is obtained in which one of an image portion, that corresponds to hard tissue such as bones or the like within the image, and an image portion, that corresponds to soft tissue, is emphasized and the other is removed. For example, when using an energy subtraction image that corresponds to soft tissue of the chest region, pathological changes that are hidden by the ribs can be seen. Accordingly, this technique can improve diagnostic performance. 
         [0008]    When an energy subtraction image is desired by using analogue X-ray films or image plates, two sets of an X-ray sensitizing screen in close contact with an X-ray film, or two imaging plates, are superimposed on each other with a filter that absorbs a portion of any radiation interposed therebetween, and radiation is irradiated a single time. Subtraction image processing is then performed on the two radiographic images obtained with each of the X-ray films or each of the image plates. Due thereto, an energy subtraction image is obtained by using analogue X-ray films, or image plates, in this manner. 
         [0009]    On the other hand, with a radiographic imaging element, there is proposed a method of photographing that, when an energy subtraction image is to be obtained, radiation of different energies are irradiated two times in succession with respect to a single radiographic imaging element, and two radiation images are obtained. Further, as shown in  FIG. 26 , with a radiographic imaging element, there is proposed a method in which two radiation images are obtained by irradiating radiation one time with two radiographic imaging elements superposed one on the other, similarly to the case of X-ray films or imaging plates. 
         [0010]    In the former photographing method, the irradiation of X-rays is carried out twice. The amount of radiation to which the subject is exposed thereby increases. Further, in the former imaging method, the images become offset between the two times irradiation is carried out. 
         [0011]    In the later imaging method however, in contrast to with X-ray films and image plates, read-out circuits at the periphery of the radiographic imaging elements, support substrates, and the like are required, as shown in  FIG. 26 . Therefore, the two radiographic imaging elements cannot be placed in close contact. Consequently, since radiation is irradiated in radial directions from a radiation source, the image size differs between each of the radiographic images obtained by the respective radiographic imaging elements. 
         [0012]    Japanese Patent Application Laid-Open (JP-A) No. 2000-298198 discloses a technique of obtaining an energy subtraction image by layering plural individual radiation detecting layers and carrying out subtraction image processing on the radiation images obtained from the respective individual radiation detecting layers. In this case, correction of the pixel size is carried out so that the pixel sizes of the respective radiation images become the same. 
         [0013]    However, any positional misalignment between respective radiographic images is preferably as small as possible when obtaining a radiographic image by radiation irradiation a single time with different energy radiation. 
       SUMMARY OF THE INVENTION 
       [0014]    The present invention provides a radiographic imaging device that can obtain a radiographic image by radiation irradiation a single time with different energy radiation, while suppressing any positional misalignment. 
         [0015]    A first aspect of the present invention is a radiographic imaging device including: a support body of flat plate shape; plural radiographic imaging elements disposed layered at one face-side of the support body, each of the radiographic imaging elements detecting radiation irradiated thereon and outputting an image signal that represents a radiographic image according to an amount of the radiation; a control section, disposed at the opposite face-side of the support body, that performs at least one of control of detection in each of the plural radiographic imaging elements, and/or signal processing on the image signal; and connection lines that connect each of the respective plural radiographic imaging elements to the control section. 
         [0016]    According to the first aspect of the present invention, the plural radiographic imaging elements are disposed layered at one face-side of the flat plate shaped support body, and the control section that performs at least one of control of detection in each of the plural radiographic imaging elements, and/or control of signal processing on the image signal, is disposed at the opposite face-side of the support body. Consequently, according to the first aspect of the present invention, the distance between the plural radiographic imaging elements can be shortened. This therefore means that the first aspect of the present invention can obtain a radiographic image by radiation irradiation a single time with different energy radiation, while suppressing any positional misalignment. 
         [0017]    In a second aspect of the present invention, in the above-described aspect, one or more of the plural radiographic imaging elements may be back-front-reversed and layered. 
         [0018]    In a third aspect of the present invention, in the above-described aspects, the plural radiographic imaging elements may each be formed in a rectangular plate shape, with a connection portion for connecting to the control section provided at each of two adjacent edges from the four edges of the radiographic imaging element, and one or more of the plural radiographic imaging elements rotated by 180° in the plane of the flat plate shape. 
         [0019]    In a fourth aspect of the present invention, in the above-described aspects, the plural radiographic imaging elements may each be disposed with plural scan lines and plural signal lines that intersect with each other, with both ends of the lines exposed in at least one of the plural scan lines and/or the plural signal lines, and with connection portions for connecting to the control section formed at both ends. 
         [0020]    In a fifth aspect of the present invention, in the above-described aspects, the plural radiographic imaging elements may each be disposed with plural scan lines and plural signal lines that intersect with each other, and with a connection portion for connection to the control section provided to at least one of the plural scan lines and/or the plural signal lines at a position that is not superimposed when the plural radiographic imaging elements are layered. 
         [0021]    In a sixth aspect of the present invention, in the above-described aspects, the plural control sections may be provided corresponding to the plural radiographic imaging elements, with each of the control sections connected through the connection lines to the corresponding radiographic imaging element. 
         [0022]    In a seventh aspect of the present invention, in the above-described aspects, the connection lines may be formed by a flexible printed substrate, with the control section provided on one face-side with a connector for connecting the connection lines, and with the control section(s) that correspond to the layered back-front-reversed radiographic imaging element(s) disposed back-front-reversed. 
         [0023]    In a eighth aspect of the present invention, in the above-described aspects, the connection lines may be formed by a flexible printed substrate, with the control section provided on both front and back faces with a connector for connecting the connection lines. 
         [0024]    In a ninth aspect of the present invention, in the above-described aspects, the control section may be provided on both front and back faces with an output terminal for outputting an image signal after the signal processing. 
         [0025]    In a tenth aspect of the present invention, in the above-described aspects, the control section may be fixed directly to the support body, or fixed indirectly to the support body by a support member. 
         [0026]    In a eleventh aspect of the present invention, in the above-described aspects, each of the plural radiographic imaging elements may be provided with a bonding layer on the face at the support body side, or on the face at the side of another radiographic imaging element, and fixed to one face of the support body by bonding. 
         [0027]    In a twelfth aspect of the present invention, in the above-described aspects, the plural radiographic imaging elements may be detachably fixed to one face of the support body by a fixing member. 
         [0028]    In a thirteenth aspect of the present invention, in the above-described aspects, a filter that absorbs radiation may also be provided, interposed between the plural radiographic imaging elements. 
         [0029]    In a fourteenth aspect of the present invention, in the above-described aspects, the filter may be fixed to one or other of the radiographic imaging elements the filter makes contact with. 
         [0030]    In a fifteenth aspect of the present invention, in the above-described aspects, the radiographic imaging elements may also include a light generation section that generates light according to the radiation irradiated thereon, a sensor section that generates charge according to illumination thereon of light generated by the light generation section, and a light blocking body that blocks light generated by the light generation section and is provided on the opposite face-side of the radiographic imaging element. 
         [0031]    In a sixteenth aspect of the present invention, in the above-described aspects, the light blocking body may be configured by a light generation section support body that supports the light generation section. 
         [0032]    In a seventeenth aspect of the present invention, in the above-described aspects, the plural radiographic imaging elements may have the same array pattern of pixel portions that detect radiation as data, for pixels configuring each respective radiographic image. 
         [0033]    The radiographic imaging device of the present invention, due to the above aspects, can obtain a radiographic image by radiation irradiation a single time with different energy radiation, while suppressing positional misalignment. 
     
    
     
       BRIEF DESCRIPTION OF THE DRAWINGS 
         [0034]    Exemplary embodiments of the present invention will be described in detail based on the following figures, wherein: 
           [0035]      FIG. 1  is a schematic configuration diagram according to a first exemplary embodiment showing a detailed configuration of a radiographic imaging element and a control section that drives the radiographic imaging element; 
           [0036]      FIG. 2  is a plan view of an imaging section according to the first exemplary embodiment, as seen from one face-side thereof; 
           [0037]      FIG. 3  is a plan view of the imaging section according to the first exemplary embodiment, as seen from the opposite face-side thereof; 
           [0038]      FIG. 4  is a cross-sectional view of the A-A line in the imaging section according to the first exemplary embodiment; 
           [0039]      FIG. 5  is a diagram showing the placement arrangement of the radiographic imaging elements according to a first exemplary embodiment; 
           [0040]      FIG. 6  is a plan view as seen from one face-side of an imaging section according to a second exemplary embodiment; 
           [0041]      FIG. 7  is a plan view as seen from the opposite face-side of the imaging section according to the second exemplary embodiment; 
           [0042]      FIG. 8  is a cross-sectional view of the A-A line in the imaging section according to the second exemplary embodiment; 
           [0043]      FIG. 9  is a diagram showing the placement arrangement of radiographic imaging elements according to the second exemplary embodiment; 
           [0044]      FIG. 10  is a plan view as seen from one face-side of an imaging section according to a third exemplary embodiment; 
           [0045]      FIG. 11  is a plan view as seen from the opposite face-side of the imaging section according to the third exemplary embodiment; 
           [0046]      FIG. 12  is a cross-sectional view of the A-A line in the imaging section according to the third exemplary embodiment; 
           [0047]      FIG. 13  is a cross-sectional view of the B-B line in the imaging section according to the third exemplary embodiment; 
           [0048]      FIG. 14  is a diagram showing the placement arrangement of radiographic imaging elements according to the third exemplary embodiment; 
           [0049]      FIG. 15  is a cross-sectional view showing the configuration of an imaging section according to another exemplary embodiment; 
           [0050]      FIG. 16  is a cross-sectional view showing the configuration of an imaging section according to another exemplary embodiment; 
           [0051]      FIG. 17  is a configuration diagram showing the detailed configuration of a radiographic imaging element according to a fourth exemplary embodiment; 
           [0052]      FIG. 18  is a plan view as seen from one face-side of an imaging section according to the fourth exemplary embodiment; 
           [0053]      FIG. 19  is a plan view as seen from the opposite face-side of the imaging section according to the fourth exemplary embodiment; 
           [0054]      FIG. 20  is a cross-sectional view of the A-A line in the imaging section according to the fourth exemplary embodiment; 
           [0055]      FIG. 21  is a diagram showing the placement arrangement of radiographic imaging elements according to the fourth exemplary embodiment; 
           [0056]      FIG. 22  is a cross-sectional view showing the configuration of an imaging section according to another exemplary embodiment; 
           [0057]      FIG. 23  is a cross-sectional view showing the configuration of an imaging section according to another exemplary embodiment; 
           [0058]      FIG. 24  is a configuration diagram showing the configuration of a radiographic imaging element according to another exemplary embodiment; 
           [0059]      FIG. 25  is a cross-sectional view showing a configuration of an imaging section according to another exemplary embodiment; and 
           [0060]      FIG. 26  is cross-sectional view showing a configuration of a related art imaging section. 
       
    
    
     DETAILED DESCRIPTION OF THE INVENTION 
       [0061]    The present invention as applied to a radiographic imaging device  100  that captures radiographic images of radiation, such as X-rays or the like, will now be explained with reference to the drawings. 
       First Exemplary Embodiment 
       [0062]    Explanation will first be given of a radiographic imaging element  10  employed in the radiographic imaging device  100  according to the first exemplary embodiment. 
         [0063]    A detailed configuration according to the first exemplary embodiment, of the radiographic imaging element  10  and a control section  12  that drives the radiographic imaging element  10 , is shown in  FIG. 1 . 
         [0064]    The radiographic imaging element  10  is provided with plural pixels  20  disposed in a two-dimensional array. Each of the pixels  20  is configured to include: a sensor portion  103 , including an upper electrode, a semiconductor layer, and a lower electrode; and a TFT switch  4 . The sensor portion  103  receives light and accumulates charge. The TFT switch  4  reads out the charge that has accumulated in the sensor portion  103 . 
         [0065]    Plural scan lines  101  and plural signal lines  3  are provided in the radiographic imaging element  10  so as to intersect with each other. The scan lines  101  switch the TFT switches  4  ON/OFF. The charge accumulated in the sensor portions  103  is read out through the signal lines  3 . 
         [0066]    A scintillator  30  (see  FIG. 2  and  FIG. 4 ) made from a GOS or the like, is applied to the surface of the radiographic imaging element  10  according to the first exemplary embodiment. In order to prevent external leakage of generated light, there is a light-blocking body  30 A at the opposite face of the scintillator  30  to that applied to the radiographic imaging element  10 , the light-blocking body  30 A blocking generated light. The light-blocking body  30 A may jointly serve as a light generation section support body that supports the scintillator  30 . The need to separately provide a member to support the scintillator  30  is removed by configuring the light-blocking body  30 A to jointly serve as the light generation section support body supporting the scintillator  30 . 
         [0067]    In the radiographic imaging element  10 , irradiated radiation, such as X-rays or the like, is converted into light in the scintillator  30 , and is illuminated onto the sensor portion  103 . The sensor portion  103  receives the illuminated light from the scintillator  30  and accumulates charges. 
         [0068]    An electrical signal (image signal), representing a radiographic image according to the charge amount accumulated in the respective sensor portions  103 , flows in each of the respective signal lines  3  when whichever of the TFT switches  4  that is connected to the given signal line  3  is switched ON. 
         [0069]    A connector  40  is provided at one end of the radiographic imaging element  10  in the signal line direction. A connector  42  is provided at one end of the radiographic imaging element  10  in the scan line direction. Each of the signal lines  3  is connected to the connector  40 . Further, each of the scan lines  101  is connected to the connector  42 . 
         [0070]    The control section  12  is provided in the first exemplary embodiment to control detection of radiation by the radiographic imaging element  10  and to control signal processing to the electrical signal flowing in each of the signal lines  3 . The control section  12  is equipped with a signal detection circuit  105  and a scan signal control circuit  104 . 
         [0071]    The signal detection circuit  105  is connected to the connector  40  via connection lines  41 . Further, the signal detection circuit  105  is installed with an amplifier circuit for each of the respective signal lines  3 , and the amplifier circuits amplify the inputted electrical signals. In the signal detection circuit  105 , electrical signals inputted by each of the signal lines  3  are amplified by the amplifier circuits and is detected. The signal detection circuit  105  thereby detects the charge amount that has accumulated in each of the sensor portions  103  as data for each of the pixels  20  configuring an image. 
         [0072]    The scan signal control circuit  104  is connected to the connector  42  via connection lines  43 . The scan signal control circuit  104  outputs a control signal to each of the scan lines  101  for switching the respective TFT switch  4  ON/OFF. 
         [0073]    Explanation will now be given of the radiographic imaging device  100  according to the first exemplary embodiment. 
         [0074]    The configuration of the radiographic imaging device  100  according to the first exemplary embodiment is shown in  FIG. 2  to  FIG. 4 . A plan view as seen from one face-side of an imaging section  14  according to the first exemplary embodiment is shown in  FIG. 2 . A plan view as seen from the opposite face-side of the imaging section  14  according to the first exemplary embodiment is shown in  FIG. 3 . A cross-sectional view of the A-A line of  FIG. 2  and  FIG. 3  is shown in  FIG. 4 . 
         [0075]    The radiographic imaging device  100  according to the first exemplary embodiment captures a radiographic image representing irradiated radiation, and includes the imaging section  14 . 
         [0076]    The imaging section  14  has two radiographic imaging elements  10  disposed layered at one face-side of a support substrate  1 , which is formed as a flat plate shape, and, corresponding to each of the radiographic imaging elements  10 , there are a signal detection circuit  105  and a scan signal control circuit  104  disposed at the opposite face-side of the support substrate  1 . Note that, since the two radiographic imaging elements  10  are superimposed on each other in the first exemplary embodiment, only the radiographic imaging element  10  on the top side is shown in  FIG. 2 . In addition, because the two signal detection circuits  105  and scan signal control circuits  104  are superimposed on each other, only the signal detection circuit  105  and the scan signal control circuit  104  at the bottom side are shown in  FIG. 3 . 
         [0077]    In order to discriminate between the two radiographic imaging elements  10 , they will be referred to as radiographic imaging elements  10 A,  10 B herebelow. Further, in order to discriminate between the two signal detection circuits  105  and scan signal control circuits  104  those corresponding to the radiographic imaging element  10 A will be referred to as signal detection circuit  105 A and scan signal control circuit  104 A, and those corresponding to the radiographic imaging element  10 B as signal detection circuit  105 B and scan signal control circuit  104 B. 
         [0078]    The radiographic imaging element  10 A has a bonding layer on the face thereof at the radiographic imaging element  10 B side. The radiographic imaging element  10 B has a bonding layer on both the face thereof at the support substrate  1  side and the face thereof at the radiographic imaging element  10 A side. The radiographic imaging element  10 B is fixed by bonding to one face of the support substrate  1 . 
         [0079]    The signal detection circuit  105 B and the scan signal control circuit  104 B are directly fixed to the support substrate  1 . The signal detection circuit  105 A and the scan signal control circuit  104 A are indirectly fixed to the support substrate  1  via support members  46  (see  FIG. 13 ). 
         [0080]    In the first exemplary embodiment, when the radiographic imaging elements  10 A,  10 B are layered, they are superimposed on each other, both facing in the same direction and with the same rotational orientation, as shown in  FIG. 5 . In  FIG. 5 , and in later described  FIG. 9 ,  FIG. 14  and  FIG. 21 , the letter “F” has been appended to the top face of the radiographic imaging elements  10 , so as to indicate the facing direction and rotational orientation of the radiographic imaging elements  10 A,  10 B. 
         [0081]    Accordingly, the radiographic imaging elements  10  are layered with the same facing direction and same rotational orientation. Therefore, in the imaging section  14  according to the first exemplary embodiment, the signal detection circuits  105  and scan signal control circuits  104  corresponding to the respective radiographic imaging elements  10  are disposed in positions where they superimpose. 
         [0082]    The connector  40  and the signal detection circuit  105 A of the radiographic imaging element  10 A are mutually connected together by the connection lines  41 . Further, the connector  40  and the signal detection circuit  105 B of the radiographic imaging element  10 B are mutually connected together by the connection lines  41 . In addition, the connector  42  and the scan signal control circuit  104 A of the radiographic imaging element  10 A are mutually connected together by connection lines  43 . The connector  42  and the scan signal control circuit  104 B of the radiographic imaging element  10 B are mutually connected together by the connection lines  43 . In the first exemplary embodiment, the connection lines  41  and the connection lines  43  are of flexible wiring, formed by a flexible printed substrate. 
         [0083]    Explanation will now be given of operation of the radiographic imaging device  100  according to the first exemplary embodiment. 
         [0084]    In the radiographic imaging device  100 , when imaging, for example, an X-ray image, X-rays that have passed through an imaging subject are irradiated onto the imaging sections  14  in the radiographic imaging elements  10 . The X-rays that have passed through the imaging subject include high energy components and low energy components. 
         [0085]    In the imaging sections  14  the radiographic imaging elements  10 A,  10 B are disposed layered on each other at one face-side of the support substrate  1 , as shown in  FIG. 4 . Therefore, the low energy X-rays are absorbed in the radiographic imaging element  10 A and do not reach the radiographic imaging element  10 B, and a portion of the high energy X-rays are absorbed in the radiographic imaging element  10 A. However, the remaining portion of the high energy X-rays passes through the radiographic imaging element  10 A and reaches the radiographic imaging element  10 B. Due to the above, the radiographic imaging element  10 A has sensitivity to the low energy and high energy X-rays. The radiographic imaging element  10 B has sensitivity to high energy X-rays. 
         [0086]    Charges are generated due to X-ray irradiation in each of the sensor portions  103  in the radiographic imaging elements  10 A,  10 B. 
         [0087]    When reading out images, an ON signal (+10 to 20V) is sequentially applied from the scan signal control circuits  104 A,  104 B to the gate electrodes of the TFT switches  4  of the radiographic imaging elements  10 A,  10 B, via the scan lines  101 . The TFT switches  4  of the radiographic imaging elements  10 A,  10 B are thereby sequentially switched ON. Due to this, an electrical signal corresponding to the charge amount accumulated in the sensor portion  103  flows out in the signal lines  3 . The signal detection circuits  105 A,  105 B, based on the electrical signal flowing out in the signal lines  3  of the radiographic imaging elements  10 A,  10 B, detects the charge amount accumulated in each of the sensor portions  103 , as a data for each of the pixels  20  configuring an image. The radiographic imaging device  100  can thereby obtain image data representing an image that shows the radiation irradiated onto the radiographic imaging elements  10 A,  10 B. 
         [0088]    In the radiographic imaging element  10  according to the first exemplary embodiment, there are two radiographic imaging elements  10  disposed layered at one face-side of the support substrate  1 , and the signal detection circuits  105  and the scan signal control circuits  104  of the respective radiographic imaging elements  10  are disposed on the opposite face-side of the support substrate  1 . 
         [0089]    Accordingly, in the first exemplary embodiment there are two sheets of radiographic imaging elements  10  disposed layered at one face-side of the support substrate  1 . In the first exemplary embodiment the separation distance between each of the radiographic imaging elements  10  can thereby be made small. Consequently the first exemplary embodiment can suppress to a small amount difference in the image size of each of the radiographic images obtained from the respective radiographic imaging elements  10 . 
         [0090]    Further, according to the first exemplary embodiment, the signal detection circuits  105  and the scan signal control circuits  104  of the radiographic imaging elements  10  are disposed on the opposite face-side of the support substrate  1 . Consequently, the first exemplary embodiment can have a thinner imaging section  14 , in comparison to cases where the signal detection circuits  105  and the scan signal control circuits  104  are provided to separate support substrates  1  and then stacked, as shown in  FIG. 26 . 
         [0091]    Furthermore, in the first exemplary embodiment, the signal detection circuits  105  and the scan signal control circuits  104  are disposed on the opposite face-side of the support substrate  1 . Therefore radiation is absorbed by the support substrate  1 . Consequently, in the first exemplary embodiment the signal detection circuits  105  and the scan signal control circuits  104  can be protected from radiation. 
       Second Exemplary Embodiment 
       [0092]    Explanation will now be given of a second exemplary embodiment. 
         [0093]    The configuration of the radiographic imaging elements  10  according to the second exemplary embodiment is similar to those of the above first exemplary embodiment (see  FIG. 1 ) and explanation thereof will therefore be omitted. 
         [0094]    A configuration of a radiographic imaging device  100  according to the second exemplary embodiment is shown in  FIG. 6  to  FIG. 8 . A plan view as seen from one face-side of an imaging section  14  according to the second exemplary embodiment is shown in  FIG. 6 . A plan view as seen from the opposite face-side of the imaging section  14  according to the second exemplary embodiment is shown in  FIG. 7 . A cross-sectional view of the A-A line of  FIG. 6  and  FIG. 7  is shown in  FIG. 8 . Portions that are similar to those of the above first exemplary embodiment (see  FIG. 2  to  FIG. 4 ) are allocated the same reference numerals, and explanation thereof is omitted. 
         [0095]    In the imaging section  14  according to the second exemplary embodiment, the radiographic imaging elements  10 A,  10 B are disposed layered at one face-side of a support substrate  1  that is formed in a flat plate shape. In the imaging section  14  according to the second exemplary embodiment, the signal detection circuits  105 A,  105 B and the scan signal control circuits  104 A,  104 B of the radiographic imaging elements  10  are disposed on the opposite face-side of the support substrate  1 . 
         [0096]    In the second exemplary embodiment, when the two radiographic imaging elements  10  are layered, as shown in  FIG. 9 , one of the radiographic imaging elements  10  is rotated by 180° in the plane of the flat plate-shaped radiographic imaging element  10 . In the second exemplary embodiment the radiographic imaging element  10 A is rotated by 180° in the plane thereof and then superimposed. 
         [0097]    According to the second exemplary embodiment as described above, one of the two radiographic imaging elements  10  is rotated by 180° with respect to the other and then layered. Consequently, in the imaging section  14  according to the second exemplary embodiment the signal detection circuits  105  and the scan signal control circuits  104  of each of the radiographic imaging elements  10  are disposed in non-superimposed positions. Accordingly, the thickness of the imaging section  14  according to the second exemplary embodiment can thereby be made even thinner. 
       Third Exemplary Embodiment 
       [0098]    Explanation will now be given of a third exemplary embodiment. 
         [0099]    The configuration of the radiographic imaging element  10  according to the third exemplary embodiment is similar to that of the above first exemplary embodiment (see  FIG. 1 ) and explanation thereof will therefore be omitted. 
         [0100]    A configuration of a radiographic imaging device  100  according to the third exemplary embodiment is shown in  FIG. 10  to  FIG. 13 . A plan view as seen from one face-side of an imaging section  14  according to the third exemplary embodiment is shown in  FIG. 10 . A plan view as seen from the opposite face-side of the imaging section  14  according to the third exemplary embodiment is shown in  FIG. 11 . A cross-sectional view of the A-A line of  FIG. 10  and  FIG. 11  is shown in  FIG. 12 . A cross-sectional view of the B-B line of  FIG. 10  and  FIG. 11  is shown in  FIG. 13 . Portions that are similar to those of the above first exemplary embodiment (see  FIG. 2  to  FIG. 4 ) are allocated the same reference numerals, and explanation thereof is omitted. Since the scan signal control circuits  104  are superimposed on each other in the third exemplary embodiment, only the scan signal control circuit  104  at the topside is shown in  FIG. 11 . 
         [0101]    In the imaging section  14  according to the third exemplary embodiment, the radiographic imaging elements  10 A,  10 B are disposed layered at one face-side of a support substrate  1  that is formed in a flat plate shape. The signal detection circuits  105 A,  105 B and the scan signal control circuits  104 A,  104 B of the radiographic imaging elements  10  are disposed on the opposite face-side of the support substrate  1 . 
         [0102]    In the third exemplary embodiment, when the two radiographic imaging elements  10  are layered, the front and back faces of one of the radiographic imaging element  10  are reversed before stacking, as shown in  FIG. 14 . In the third exemplary embodiment the radiographic imaging element  10 A is superimposed with its front and back faces reversed. 
         [0103]    By so doing, according to the third exemplary embodiment, one of the two radiographic imaging elements  10  is layered with its front and back faces reversed with respect to the other. Therefore, in the imaging section  14  according to the third exemplary embodiment, either the signal detection circuits  105  or the scan signal control circuits  104  of the radiographic imaging elements  10  are disposed in a superimposed position, with the other disposed in a non-superimposed position. Consequently, the third exemplary embodiment of the present invention can reduce the thickness of the imaging section  14 , in comparison to cases where the signal detection circuits  105  and the scan signal control circuits  104  are provided as the control section  12  of the radiographic imaging element  10  on separate support substrates  1  and then stacked, as shown in  FIG. 26 . 
         [0104]    It should be noted that, the back-front-reversed radiographic imaging element  10 A according to the third exemplary embodiment, as shown in  FIG. 12  and  FIG. 13 , may be configured with the signal detection circuit  105 A and the scan signal control circuit  104 A reversed. In another exemplary embodiment, the signal detection circuit  105  and the scan signal control circuit  104  that have been back-front-reversed may also be indirectly fixed to the support substrate  1  via support members  46 . In the third exemplary embodiment, as shown in  FIG. 13 , the signal detection circuit  105 A is indirectly fixed to the support substrate  1 . By so doing the radiographic imaging elements  10 A,  10 B are able to utilize the same signal detection circuits  105  and scan signal control circuits  104 . 
         [0105]    Note that in another exemplary embodiment, connectors for connecting the connection lines  41  and the connection lines  43  to the signal detection circuits  105  and the scan signal control circuits  104  may be provided at the two faces, front and back. In  FIG. 15 , an example is shown in which connectors  110  are provided to the two faces, front and back, of the signal detection circuits  105 A,  105 B for connecting the connection lines  41 . By so doing, in this another exemplary embodiment, even when the front and back of the signal detection circuit  105  have been reversed, one or other of the connectors  110  is on the front face side. Consequently, the connection lines  41  are more readily connected to the connector  110  in this other exemplary embodiment. 
         [0106]    In another exemplary embodiment, connectors may be provided on both of the two faces, front and rear, in order to connect another circuit, such as a control section for controlling operation of the signal detection circuits  105  and the scan signal control circuits  104 . An example is shown in  FIG. 16  in which connectors  112  for connection to another circuit, such as a control section, are provided on the two faces, front and rear, of the signal detection circuits  105 A,  105 B. By so doing, even when the front and back of the signal detection circuit  105  have been reversed, one or other of the connectors  112  is on the front face. Consequently, the signal detection circuits  105  are more readily connected to another circuit in this other exemplary embodiment. 
       Fourth Exemplary Embodiment 
       [0107]    Explanation will now be given of a fourth exemplary embodiment. 
         [0108]    A detailed configuration of a radiographic imaging element  10  according to the fourth exemplary embodiment is shown in  FIG. 17 . Portions that are similar to those of the above first exemplary embodiment (see  FIG. 1 ) are allocated the same reference numerals, and explanation thereof is omitted. 
         [0109]    In the radiographic imaging element  10  according to the fourth exemplary embodiment, exposed regions  44  are provided at both end portions of each of the scan lines  101 , through which the scan lines  101  are exposed. In the fourth exemplary embodiment, connectors  42  are formable to each of the exposed regions  44  at the two ends in the scan line direction. 
         [0110]    A configuration of a radiographic imaging device  100  according to the fourth exemplary embodiment is shown in  FIG. 18  to  FIG. 20 . It should be noted that, a plan view as seen from one face-side of an imaging section  14  according to the fourth exemplary embodiment is shown in  FIG. 18 . A plan view as seen from the opposite face-side of the imaging section  14  according to the fourth exemplary embodiment is shown in  FIG. 19 . A cross-sectional view of the A-A line of  FIG. 18  and  FIG. 19  is shown in  FIG. 20 . Portions that are similar to those of the above first exemplary embodiment (see  FIG. 2  to  FIG. 4 ) are allocated the same reference numerals, and explanation thereof is omitted. 
         [0111]    In the imaging section  14  according to the fourth exemplary embodiment, the radiographic imaging elements  10 A,  10 B are disposed layered at one face-side of a support substrate  1  that is formed in a flat plate shape. In the imaging section  14  according to the fourth exemplary embodiment, the signal detection circuits  105 A,  105 B and the scan signal control circuits  104 A,  104 B of the radiographic imaging elements  10  are disposed on the opposite face-side of the support substrate  1 . 
         [0112]    In the fourth exemplary embodiment, when the two radiographic imaging elements  10  are layered, the front and back of one of the radiographic imaging element  10  are reversed and then layered, as shown in  FIG. 21 . In the fourth exemplary embodiment the front and back of the radiographic imaging element  10 A are reversed and then superimposed. 
         [0113]    When the two radiographic imaging elements  10  are layered with one of the radiographic imaging elements  10  back-front-reversed with respect to the other, the scan signal control circuits  104  are disposed in a superimposed position. In the fourth exemplary embodiment, as shown in  FIG. 21 , connectors  42  are formable to both ends of the radiographic imaging elements  10 A,  10 B in the scan line direction. Therefore, in the fourth exemplary embodiment, the position provided with the connectors  42  is changeable such that the connectors  42  are not superimposed on each other when the radiographic imaging elements  10 A,  10 B are layered. By so doing, in the fourth exemplary embodiment, the scan signal control circuits  104  are disposed in non-superimposed positions. Due thereto, from the standpoint of noise reduction and the like, the exposed region  44  of the radiographic imaging element  10  not provided with the connector  42  is preferably insulated by an insulating member  47 . 
         [0114]    Thereby, according to the fourth exemplary embodiment, the signal detection circuits  105  and the scan signal control circuits  104  corresponding to the respective radiographic imaging elements  10  are disposed in non-superimposed positions. Consequently, the thickness of the imaging section  14  can be reduced in the fourth exemplary embodiment. 
         [0115]    In each of the above exemplary embodiments, explanation has been given of cases where the radiographic imaging element  10 A and the radiographic imaging element  10 B are fixed to the opposite side of the support substrate  1  by bonding. However, the present invention is not limited thereto. For example, as shown in  FIG. 22 , the radiographic imaging element  10 A and the radiographic imaging element  10 B may be fixed detachably to one face-side of the support substrate  1  by use of fixing members  48 . Accordingly, if one or other of the radiographic imaging element  10 A and the radiographic imaging element  10 B fails, replacement can be made of solely the failed element. 
         [0116]    When the absorption of low energy X-rays by the radiographic imaging element  10 A is insufficient, or when a greater energy difference is desired for the X-rays imaged by the radiographic imaging elements  10 A,  10 B, then, as shown in  FIG. 23 , a filter  50  may be provided between the radiographic imaging element  10 A and the radiographic imaging element  10 B for absorbing radiation of low energy. By provision of the filter  50 , the energy difference between the X-rays imaged by the radiographic imaging elements  10 A,  10 B can be increased. 
         [0117]    The filter  50  can be realized by provision of a thin metal plate. However, the bonding layer can also have a combined use as the energy filter by incorporating a powder, such as titanium oxide (TiO 2 ), aluminum oxide (Al 2 O 3 ), or the like, into a binder made from a polyurethane resin. 
         [0118]    In the first and the third exemplary embodiments above, explanation has been given of cases where the signal detection circuits  105  and the scan signal control circuits  104  are superimposed. However, the present invention is not limited thereto. For example, the connectors  40 ,  42  may be formed for a given number of the signal lines  3  and a given number of the scan lines  101  in the radiographic imaging elements  10 . In addition, the connectors  40 ,  42  may be provided in positions that are not superimposed when the radiographic imaging element  10 A and the radiographic imaging element  10 B are layered. An example is shown in  FIG. 24  where the connectors  42  of the respective radiographic imaging elements  10 A,  10 B are provided in non-superimposing positions. 
         [0119]    In each of the above exemplary embodiments, explanation has been given of cases where plural of the signal detection circuits  105  and the scan signal control circuits  104  are provided, corresponding to the number of radiographic imaging elements  10 . However, the present invention is not limited thereto. For example, as shown in  FIG. 25 , the radiographic imaging elements  10  may be controlled by a single signal detection circuit  105  and a single scan signal control circuit  104 . 
         [0120]    In the fourth exemplary embodiment above, explanation has been given of a case in which the exposed regions  44  are provided at two end portions of the radiographic imaging elements  10  in the scan line direction, and both ends are formable with the connectors  42 . However, the present invention is not limited thereto. For example, an exposed region where the signal lines  3  are exposed may be provided at both end portions in the signal line direction, with both ends formable with the connectors  40 . Thereby, when the signal detection circuits  105  would be superimposed when two of the radiographic imaging elements  10  are layered, the signal detection circuits  105  can be disposed in non-superimposing positions by changing the position of the connectors  40 . 
         [0121]    The connector may be formable at both end portions of the radiographic imaging element  10  in the scan line direction and in the signal line direction. By so doing, for example, even when both the signal detection circuits  105  and the scan signal control circuits  104  would be superimposed as in the first exemplary embodiment, the signal detection circuits  105  and the scan signal control circuits  104  can be disposed in non-superimposing positions. 
         [0122]    In the second exemplary embodiment above, explanation has been given of a case where one of the radiographic imaging elements  10  is rotated by 180° and layered, and in the third exemplary embodiment above of a case where one of the radiographic imaging elements  10  is back-front-reversed and layered, and in the fourth exemplary embodiment above of a case where both end portions of each of the scan lines  101  and both end portions of each of the signal lines  3  of the radiographic imaging element  10  are formable with a connector. However, the radiographic imaging elements  10  may be layered with appropriate combinations of these features. 
         [0123]    In each of the above exemplary embodiments, explanation has been given of a case where the signal detection circuits  105  and the scan signal control circuits  104  are provided as a control section  12 . However, the present invention is not limited thereto. For example, a combined circuit may be provided with the functions of the signal detection circuit  105  and the scan signal control circuit  104 . Provision may also be made of one or other of the signal detection circuit  105  or the scan signal control circuit  104  alone. 
         [0124]    In each of the above exemplary embodiments, explanation has been given of a case in which application of the present invention has been made to indirect conversion radiographic imaging elements  10  that first convert radiation into light in the scintillator  30  and then convert the converted light into charge and accumulate the charge in the sensor portion  103 . However, the present invention is not limited thereto. For example, application may be made to direct-conversion-type radiographic imaging elements that directly convert radiation into charge and accumulate the converted charge in a sensor portion that utilizes amorphous selenium or the like. 
         [0125]    In the above exemplary embodiments, explanation has been given of cases where the same radiographic imaging elements are used for the radiographic imaging elements  10 A,  10 B. However, the present invention is not limited thereto. For example, radiographic imaging elements may be used that have different array patterns or numbers of the pixels  20 , or direct-conversion-type. 
         [0126]    In addition the configurations of the radiographic imaging element  10  (see  FIG. 1  and  FIG. 17 ) and the configurations of the radiographic imaging device  100  (see  FIG. 2  to  FIG. 16 , and  FIG. 18  to  FIG. 25 ) explained in the above exemplary embodiments are only examples, and various appropriate modifications and variations may be made within a scope that does not depart from the spirit of the present invention.