Radiation imaging device

Abstract

To reduce an electric field generated in the vicinity of an antenna provided in a radiation imaging device without adding a new component.SOLUTION: A radiation imaging device 100, 100A, 100B, or 100C includes: a sensor panel 3 (3A) having an imaging surface 321a in which a plurality of semiconductor elements 322 are distributed two-dimensionally; a communication unit 65 having an antenna 65b and performing wireless communication with other devices; and a conductor layer L (first and second shield layers 4 and 8, moisture-proof layers 33 and 36A, front part 11, back part 21) spreading along the imaging surface 321a and reflecting an electromagnetic wave emitted by the antenna 65b. A wavelength λ of the electromagnetic wave and a distance d from the antenna 65b to a plane P including the conductor layer L satisfies a relation of 0<d<Nλ+λ / 8, Nλ+3λ / 8<d<Nλ+5λ / 8, or Nλ+7λ / 8<d<Nλ+9λ / 8 where N is any integer greater than or equal to 0.SELECTED DRAWING: Figure 2

Description

[Technical field]

[0001] The present invention relates to a radiation imaging apparatus. [Background technology]

[0002] Portable radiation imaging devices (e.g., Flat Panel Detectors: FPDs) have a wireless communication function for transferring image data of generated radiation images to other devices, i.e., they often have an antenna that emits electromagnetic waves for communication. In order to transfer image data to a device located farther away using such a radiation imaging device, it is necessary to increase the output of the electromagnetic waves emitted by the antenna. On the other hand, such radiation imaging devices are often used in contact with the subject. This puts the subject in a situation where the subject is likely to absorb the electromagnetic waves generated in the vicinity of the antenna when the antenna emits the electromagnetic waves. Since strong electromagnetic waves have a negative effect on the human body, radiation imaging devices with wireless communication functions must be configured so that the Specific Absorption Rate (SAR), which is a measure of the human body's absorption of electromagnetic waves, does not exceed the prescribed regulatory value. Conventionally, as a means for achieving both an increase in the output of electromagnetic waves and a reduction in SAR, a laminated soft magnetic member as described in Patent Document 1, for example, has been incorporated into a radiation imaging device. [Prior art documents] [Patent documents]

[0003] [Patent Document 1] JP 2004-303824 A Summary of the Invention [Problem to be solved by the invention]

[0004] However, the laminated soft magnetic member used in the conventional SAR reduction technology as described in Patent Document 1 is a dedicated component for reducing the electric field generated in the vicinity of the antenna. When such dedicated components are newly incorporated into the radiation imaging apparatus, there arises a problem that the weight of the radiation imaging apparatus increases as compared with the conventional one. In addition, when newly incorporating dedicated components, problems such as a reduction in the space inside the radiation imaging apparatus (increase in the size of the apparatus, decrease in the degree of freedom in design), and an increase in manufacturing costs also occur.

[0005] The present invention has been made in view of the above problems, and an object thereof is to be able to reduce the electric field generated in the vicinity of the antenna included in the radiation imaging apparatus without adding new components.

Means for Solving the Problems

[0006] To solve the above problems, the radiation imaging apparatus according to the present invention includes a sensor panel having an imaging surface on which a plurality of semiconductor elements are arranged so as to be two-dimensionally distributed, a communication unit having an antenna and performing wireless communication with other devices, a conductor layer that spreads along the imaging surface and reflects the electromagnetic wave emitted by the antenna, wherein the wavelength λ of the electromagnetic wave and the distance d from the antenna to the plane including the conductor layer satisfy the relationship of 0 < d < Nλ + λ / 8, Nλ + 3λ / 8 < d < Nλ + 5λ / 8, or Nλ + 7λ / 8 < d < Nλ + 9λ / 8 (where N is an arbitrary integer of 0 or more).

Effects of the Invention

[0007] The conductor layer is often provided in the radiation imaging apparatus conventionally. Therefore, according to the present invention, the electric field generated in the vicinity of the antenna included in the radiation imaging apparatus can be reduced without adding new components.

Brief Description of the Drawings

[0008] [Figure 1] It is an exploded perspective view of a radiation imaging apparatus according to the first to fourth embodiments of the present invention. [Diagram 2]1 is a cross-sectional view of a radiation imaging apparatus according to a first embodiment. [Diagram 3] 1 is a graph illustrating a mechanism for reducing electromagnetic waves. [Figure 4] FIG. 11 is a cross-sectional view of a radiation imaging apparatus according to a modified example of the first embodiment. [Diagram 5] FIG. 11 is a cross-sectional view of a radiation imaging apparatus according to a second embodiment. [Figure 6] FIG. 11 is a cross-sectional view of a radiation imaging apparatus according to a third embodiment. [Figure 7] FIG. 13 is a cross-sectional view of a sensor panel included in a radiation imaging apparatus according to a fourth embodiment. DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

[0009] Hereinafter, an embodiment of the present invention will be described with reference to the drawings. However, the present invention is not limited to the embodiment shown in the drawings.

[0010] <1. First embodiment> First, a first embodiment of the present invention will be described.

[0011] First, a schematic configuration of a radiation imaging apparatus (hereinafter, imaging apparatus 100) according to this embodiment will be described. FIG. 1 is an exploded perspective view of the imaging device 100, FIG. 2 is a cross-sectional view of the imaging device (cut along the thickness direction of the imaging device 100), and FIG. 3 is a graph explaining a mechanism for reducing electromagnetic waves.

[0012] The imaging device 100 is for generating a radiation image according to the dose distribution of the received radiation. The imaging device 100 includes a housing 110 and an internal module 120, as shown in FIG. The imaging device 100 according to this embodiment includes various switches (power switch, operation switch, etc.), indicators, and the like.

[0013] [1-1. Cabinet] The housing 110 is for housing an internal module 120 . The housing 110 according to this embodiment has a rectangular panel shape, which means that the imaging device 100 according to this embodiment is portable. The housing 110 includes a box body 1 and a cover body 2.

[0014] [1-1-1. Box body] The box 1 has a front surface 11 . The box 1 according to this embodiment further includes a side surface portion 12. The front portion 11 and the side portion 12 according to this embodiment are integrally formed. The front surface portion 11 and the side surface portion 12 may be separate members.

[0015] (Front part) The front surface portion 11 is formed in a rectangular flat plate shape. Moreover, the outer surface of the front surface part 11 becomes a radiation incident surface 11a (front surface) of the imaging device 100 (housing 110). The front surface portion 11 according to this embodiment is formed in a rectangular plate shape.

[0016] The front surface 11 is formed from a material that does not impede the transmission of radiation. Specific examples of materials that do not impede the transmission of radiation include carbon fiber reinforced plastic (CFRP), glass fiber reinforced plastic (GFRP), and light metals such as Al and Mg.

[0017] (side part) The side surface portion 12 extends from the peripheral edge of the front surface portion 11 in a direction perpendicular to the radiation entrance surface 11a and away from the front surface portion 11. Moreover, the outer surface of the side surface portion 12 becomes the side surface of the imaging device 100 (housing 110).

[0018] [1-1-2. Lid] The cover 2 has a rear surface portion 21 . The cover 2 according to this embodiment has a rear surface portion 21 as a whole. The rear surface portion 21 according to this embodiment is formed in a rectangular shape that is substantially the same as that of the front surface portion 11 . Specific examples of materials from which the back portion 21 can be formed include carbon fiber reinforced resin, glass fiber reinforced resin, light metals such as Al and Mg, and the like. The back surface portion 21 may be made of the same material as the box 1, or may be made of a different material.

[0019] The rear surface portion 21 faces the front surface portion 11 of the box body 1 with the internal module 120 interposed therebetween, and is disposed so as to extend in parallel with the front surface portion 11 . Therefore, the outer surface of the rear surface part 21 becomes the rear surface of the imaging device 100 (housing 110). Further, the back surface portion 21 abuts against the side surface portion 12 of the box body 1 and is attached to the side surface portion 12 . The lid 2 according to this embodiment is fixed to the side surface portion 12 of the box 1 with screws.

[0020] [1-1-3. Housing and other items] Although FIG. 1 illustrates an example of a housing 110 (box body 1) in which the side portion 12 is integrally formed with the front portion 11, the housing 110 may be one in which the side portion 12 is integral with the rear portion 21, or the front portion 11, the side portion 12, and the rear portion 21 may each be separate components. Additionally, both the front portion 11 and the rear portion 21 may have side portions. In addition, while FIG. 1 illustrates an example of a housing 110 having a box body 1 and a lid body 2, the housing may also include a cylindrical body having a front portion 11, a rear portion 21, and a pair of side portions 12 respectively connecting both ends of the front portion 11 and both ends of the rear portion 21, and a lid body that closes the opening of the cylindrical body.

[0021] [1-2. Internal module] The internal module 120 is housed in the housing 110 . The internal module 120 is fixed to at least one of the inner surfaces of the front portion 11 , the rear portion 21 and the side portion 12 of the housing 110 . Methods for fixing the internal module 120 to the housing 110 include bonding with an adhesive, adhesion with an adhesive tape, fitting into a recess or protrusion formed on the inner surface, engaging with an engagement portion formed on the inner surface, etc.

[0022] The internal module 120 includes a sensor panel 3, a first shield layer 4, a base 5, electronic components 6, and a conductor layer L, as shown in FIG. Moreover, the inner module 120 according to this embodiment further includes a radiation attenuation layer 7 and a second shield layer 8. Each of the parts 3 to 8 and L is fixed inside the housing 110 by a spacer, an adhesive material, or the like (not shown).

[0023] [1-2-1. Sensor panel] The sensor panel 3 according to this embodiment includes a wavelength conversion section 31, a photoelectric conversion section 32, and a moisture-proof layer 33.

[0024] (Wavelength conversion section) The wavelength conversion section 31 is for converting radiation into visible light or the like. The wavelength converting portion 31 according to this embodiment has a scintillator 311 . The scintillator 311 includes a deposition substrate and a phosphor layer.

[0025] The deposition substrate is for supporting the phosphor layer. The deposition substrate according to this embodiment is formed in a rectangular plate shape that is slightly smaller than the radiation incident surface 11a of the housing 110.

[0026] The phosphor layer is made of a phosphor and is formed in the form of a film on the entire surface of the deposition substrate opposite to the side on which the front portion 11 of the housing 110 is present. A phosphor is a substance that emits light by exciting atoms when irradiated with ionizing radiation such as alpha rays, gamma rays, or X-rays. In other words, phosphors convert radiation into ultraviolet light or visible light. The phosphor includes, for example, columnar crystals of cesium iodide (CsI). The phosphor layer may be formed on the surface of the photoelectric conversion section 32, which will be described later. In this case, the deposition substrate is not necessary.

[0027] (Moisture-proof layer) The moisture-proof layer 33 covers the scintillator 311 to prevent moisture from reaching the scintillator 311 . The moisture-proof layer 33 has a portion that covers the front surface of the scintillator 311 and a portion that covers the side surfaces. The portion covering the front surface of the moisture-proof layer 33 extends along the imaging surface 321a. The moisture-proof layer 33 in this embodiment is an aluminum foil. Aluminum reflects electromagnetic waves (emitted by antenna 65b) that arrive from the surroundings. Therefore, the moisture-proof layer 33 according to this embodiment also serves as the conductor layer L.

[0028] Moreover, the thickness of the moisture-proof layer 33 (aluminum foil) according to this embodiment is 9 um or more. Aluminum foil with a thickness of 9um or more is 1.0g / m 2 Therefore, by doing so, the scintillator 311 can be sufficiently moisture-proof. The thickness of the moisture-proof layer 33 may be 10 μm or more. Since aluminum has a low electrical resistivity, this allows it to reflect 99% or more of electromagnetic waves. That is, the moisture-proof layer 33 according to this embodiment can reduce the weight of the conductor layer L and thus the imaging device 100, while reliably reflecting electromagnetic waves and preventing moisture from being applied to the scintillator.

[0029] The wavelength conversion section 31 configured in this manner is disposed so that the deposition substrate faces the front surface 11 of the housing 110 and extends parallel to the radiation incident surface 11a of the housing 110. In the wavelength conversion section 31 configured in this manner, the area exposed to radiation emits light with an intensity according to the dose of the radiation received. The entire wavelength converting portion 31, including the deposition substrate, may be flexible.

[0030] (Photoelectric conversion section) The photoelectric conversion section 32 serves to convert light into an electrical signal. The photoelectric conversion section 32 is disposed on the side of the wavelength conversion section 31 where the base 5 is present.

[0031] The photoelectric conversion unit 32 includes a substrate 321 and a plurality of semiconductor elements 322 (see FIG. 1). Moreover, the photoelectric conversion section 32 according to this embodiment has a plurality of scanning lines, a plurality of signal lines, a plurality of switching elements, and a plurality of bias lines, all of which are not shown.

[0032] The substrate 321 according to this embodiment is formed in a rectangular plate shape that is slightly larger than the outline of the wavelength conversion section 31 . The substrate 321 is disposed so as to extend in parallel with the wavelength converting section 31 .

[0033] The multiple scanning lines according to this embodiment are formed on the surface of the substrate 321 so as to extend parallel to one another at equal intervals. The signal lines according to this embodiment are formed on the surface of the substrate 321 on which the scanning lines are provided, at equal intervals and perpendicular to the scanning lines. That is, the surface of the substrate 321 according to this embodiment has a plurality of rectangular regions surrounded by a plurality of scanning lines and a plurality of signal lines.

[0034] Each of the semiconductor elements 322 generates an amount of charge according to the intensity of the light received. As shown in FIG. 1, the semiconductor elements 322 are arranged so as to be two-dimensionally distributed on the surface of the substrate 321 on which the scanning lines and signal lines are provided. Specifically, the semiconductor elements 322 according to this embodiment are arranged in rectangular regions surrounded by a plurality of scanning lines and a plurality of signal lines. Therefore, the multiple semiconductor elements 322 according to this embodiment are arranged in a matrix.

[0035] In addition, a switch element is provided in each rectangular region. The switch element according to this embodiment is formed of, for example, a TFT (Thin Film Transistor). Each switch element has a gate connected to a scanning line, a source connected to a signal line, and a drain connected to a semiconductor element. Hereinafter, the surface of the substrate 321 on which the plurality of semiconductor elements 322 are formed is referred to as an imaging surface 321a.

[0036] The photoelectric conversion section 32 configured in this manner is arranged so that the imaging surface 321a faces the direction in which the wavelength conversion section 31 exists, and extends in parallel to the wavelength conversion section 31, as shown in FIG. In the photoelectric conversion unit 32 according to this embodiment, the imaging surface 321 a is attached to the wavelength conversion unit 31 .

[0037] [1-2-2. Radiation attenuation layer] The radiation attenuation layer 7 is intended to absorb backscattered radiation and to prevent radiation from the front from reaching the electronic component 6. The radiation attenuation layer 7 according to this embodiment is made of lead and is formed in a rectangular sheet shape having approximately the same contour as the sensor panel 3 . The radiation attenuation layer 7 may be made of a material other than lead, such as tungsten or molybdenum. The thickness of the radiation attenuation layer 7 according to this embodiment (the width in the direction perpendicular to the radiation incident surface 11a) is within a range of 70 to 90 μm, and is preferably 80 μm.

[0038] The radiation attenuation layer 7 according to this embodiment is disposed between the sensor panel 3 (photoelectric conversion section 32) and the base 5 so as to extend in parallel to the sensor panel 3. In addition, the radiation attenuation layer 7 in this embodiment is attached to at least one of the surface of the sensor panel 3 facing the direction in which the base 5 is located and the surface of the base 5 facing the direction in which the sensor panel 3 is located. The radiation attenuation layer 7 may be in the form of a film deposited on the surface of the adjacent member.

[0039] [1-2-3. First shield layer] The first shield layer 4 is intended to prevent the magnetic field generated by the electronic components 6 from reaching the sensor panel. The first shield layer 4 is formed of a conductive material having a higher conductivity than the radiation attenuation layer 7 . The first shield layer 4 according to this embodiment is made of aluminum and is formed into a rectangular sheet shape that is approximately the same as the outline of the sensor panel 3. The first shield layer 4 may be made of any material other than aluminum, such as lithium, beryllium, sodium, magnesium, aluminum, potassium, calcium, scandium, It may be made of titanium, vanadium, chromium, manganese, iron, cobalt, nickel, copper, zinc, gallium, carbon nanotubes, fullerenes, diamond, and the like.

[0040] Moreover, the first shield layer 4 according to this embodiment is thinner than the radiation attenuation layer 7 . That is, while the thickness of the radiation attenuation layer 7 is within the range of 70 to 90 μm, the thickness of the first shield layer 4 according to this embodiment is within the range of 40 to 60 μm, and is preferably 50 μm.

[0041] The first shield layer 4 is disposed between the sensor panel 3 and the base 5 . The first shield layer 4 according to this embodiment is disposed between the radiation attenuation layer 7 and the base 5 . In addition, the first shielding layer 4 in this embodiment is attached to at least one of the surfaces of the radiation attenuation layer 7 facing the direction in which the base 5 is located and the surface of the base 5 facing the direction in which the radiation attenuation layer 7 is located. The position of the first shield layer 4 is approximately 2.70 to 2.90 mm away from the electronic component 6 when the thickness of the housing 110 (the distance from the radiation incident surface 11a to the back surface of the housing 110) is approximately 15 mm.

[0042] The first shield layer 4 may be provided between the sensor panel 3 and the radiation attenuation layer 7 . Furthermore, the first shield layer 4 may be provided between the base 5 and the electronic component 6 as long as it does not interfere with mounting the electronic component 6 to the base 5.

[0043] The first shield layer 4 may be in the form of a film deposited on the surface of the adjacent member. Furthermore, a plurality of first shield layers 4 may be provided. In this case, the multiple first shield layers 4 may be stacked on top of each other, or may be disposed between different members. In this case, the plurality of first shield layers 4 may all be made of the same material, or at least some of them may be made of different materials.

[0044] [1-2-4. Second shield layer] The second shield layer 8 is intended to prevent the magnetic field generated by the electronic components and directed toward the imaging surface 321a from reaching the sensor panel. The second shield layer 8 is made of a conductive material. The second shield layer 8 according to this embodiment is made of aluminum and is formed in a rectangular sheet shape similar to the first shield layer 4 . The conductive material forming the second shield layer 8 may be a material other than aluminum, which is given as an example of the conductive material forming the first shield layer 4.

[0045] The second shield layer 8 is disposed on the imaging surface 321a side of the sensor panel 3. That is, the second shield layer 8 is provided between the front surface part 11 of the box 1 and the sensor panel 3. The second shield layer 8 according to this embodiment is attached to at least one of the imaging surface 321a and the inner surface of the front surface portion 11.

[0046] The second shield layer 8 may be in the form of a film vapor-deposited on the surface of the adjacent member. Furthermore, a plurality of second shield layers 8 may be provided. In this case, the second shield layers 8 may all be made of the same material. At least a part of the first and second electrodes may be made of a different material.

[0047] [1-2-5. Base] The base 5 supports the sensor panel 3 from the side opposite to the side on which the imaging surface 321a exists. The base 5 is disposed between the rear portion 21 of the housing 110 and the sensor panel 3.

[0048] [1-2-6. Electronic Components] The electronic component 6 is disposed on the side of the base 5 opposite to the side on which the sensor panel 3 is present, and is connected to the photoelectric conversion unit 32 via an inter-board cable (not shown). The electronic component 6 includes a scanning unit 61 , a reading unit 62 , a control unit 63 , a power supply unit 64 , and a communication unit 65 . The scanning unit 61 has a circuit for controlling each switch element. The readout section 62 has a circuit that reads out the charge as a signal value. The control unit 63 has a circuit that controls each circuit to generate image data. The power supply unit 64 has circuits for applying voltage to the semiconductor elements and supplying power to the above-mentioned circuits.

[0049] The communication unit 65 is for communicating with other devices. The communication unit 65 includes a communication circuit 65a and an antenna 65b. The communication unit 65 according to the present embodiment also has a connector 65c (see FIG. 1) for performing wired communication. In addition, the communication unit 65 according to the present embodiment performs wireless communication using electromagnetic waves in the 2.4 GHz band or the 5 GHz band. Specifically, the communication unit 65 can be connected to a wireless LAN or Bluetooth (registered trademark) using electromagnetic waves in the 2.4 GHz band or the 5 GHz band. The electromagnetic waves in the 2.4 GHz band are used in Wi-Fi (registered trademark) and Bluetooth, and the electromagnetic waves in the 5 GHz band are used exclusively for Wi-Fi.

[0050] [1-3. Positional relationship among antenna, conductor layer, and housing] As shown in FIG. 2, the antenna 65b is attached to the housing 110. FIG. 2 illustrates a case where the antenna 65b is disposed on the side surface portion 12 of the housing 110, but the antenna 65b may be disposed on the lid body 2 (rear surface portion 21). In addition, the antenna 65b is arranged at a position where the wavelength λ of the electromagnetic wave and the distance d from the antenna 65b to the plane P including the second shield layer 8 (conductor layer L) satisfy the relationship of 0 < d < Nλ + λ / 8, Nλ + 3λ / 8 < d < Nλ + 5λ / 8, or Nλ + 7λ / 8 < d < Nλ + 9λ / 8 (where N is an arbitrary integer of 0 or more). Note that the plane P may be the surface of the conductor layer L or may be on the extension line of the surface of the conductor layer L. In addition, the front surface portion 11 of the housing 110 is located at a position where the distance from the conductor layer L is within the range of 0 to λ / 8, 3λ / 8 to 5λ / 8, or 7λ / 8 to 9λ / 8. When the antenna 65b, the conductor layer L, and the front surface portion 11 of the housing 110 are in the above-described positional relationship, when the antenna 65b emits electromagnetic waves, the electromagnetic wave (traveling wave E1) from the antenna 65b toward the conductor layer L and the electromagnetic wave (reflected wave E2) reflected by the conductor layer L interfere with each other to form a standing wave E as shown in FIG. 3, for example. Then, at node N of this standing wave and its vicinity (within a range of λ / 8, 3λ / 8 to 5λ / 8, 7λ / 8 to 9λ / 8·· from the conductor layer L), the electromagnetic waves are reduced, and the front portion 11 of the housing 110 is located in this area where the electromagnetic waves are reduced.

[0051] When the communication unit 61 uses electromagnetic waves in the 2.4 GHz band, λ / 8 is approximately 15.6 mm. The thickness of the housing 110 of the imaging device 100 is generally about 15 mm based on ISO4090 / JISZ4905. Therefore, when using electromagnetic waves in the 2.4 GHz band, in order for the distance d and the wavelength λ to satisfy the above relationship, in many cases, the antenna 65b will be attached to the rear surface (rear surface portion 21) of the housing 110. On the other hand, when the communication unit 61 uses electromagnetic waves in the 5 GHz band, λ / 8 is about 7.5 mm. As described above, the thickness of the housing 110 of the imaging device 100 is generally about 15 mm. Therefore, when using electromagnetic waves in the 5 GHz band, in order for the distance d and the wavelength λ to satisfy the above relationship, the antenna 65B is often attached to the side surface (side surface portion 12) of the housing 110.

[0052] [1-4. First embodiment and others] So far, we have described the imaging device 100 in which the moisture-proof layer 33 and the second shield layer 8 are laminated. However, if the moisture-proof layer 33 is aluminum foil (which also serves as the conductor layer L), the imaging device 100 may not have at least the second shield layer 8 of the first and second shield layers 4, 8, as shown in FIG. 4, for example (FIG. 4 shows an example in which only the second shield layer 8 is absent).

[0053] <2. Second embodiment> Next, a second embodiment of the present invention will be described. In addition, here, the same components as those in the first embodiment are denoted by the same reference numerals, and the description thereof will be omitted.

[0054] The radiation imaging apparatus according to this embodiment (hereinafter, imaging apparatus 100A) has a configuration of the housing 110A and the internal module 120A that is different from that of the first embodiment.

[0055] [2-1. Internal Module] The internal module 120A according to this embodiment does not include at least one of the first and second shield layers 4 and 8, for example, as shown in FIG. 5 (FIG. 5 illustrates a case where both the first and second shield layers 4 and 8 are absent).

[0056] [2-2. Housing] In the housing 110A according to this embodiment, at least one of the front surface portion 11A and the back surface portion 21A is formed of metal. And, among the front surface portion 11A and the back surface portion 21A, the member formed of metal also serves as the conductor layer L. That is, the relationship that the wavelength λ of the electromagnetic wave and the distance d from the antenna 65b to the front surface portion 11 or the back surface portion 21 satisfies 0 < d < Nλ + λ / 8, Nλ + 3λ / 8 < d < Nλ + 5λ / 8, or Nλ + 7λ / 8 < d < Nλ + 9λ / 8 (where N is an arbitrary integer of 0 or more) is satisfied. When the front surface portion 11A is formed of metal, the side surface portion 12A may also be formed of metal.

[0057] [2-3. Second Embodiment and Others] When the front surface portion 11A or the back surface portion 21A of the housing 110A also serves as the conductor layer L as in this embodiment, the wavelength conversion portion 31A of the sensor panel 3A of the internal module 120A does not necessarily need to include the moisture-proof layer 33. In this case, the wavelength conversion portion 31A may be configured to protect the scintillator 311 from moisture by a cover that covers the phosphor layer from the side opposite to the deposition substrate and a sealing material that surrounds the phosphor layer between the peripheral edge of the deposition substrate and the peripheral edge of the cover.

[0058] <3. Third Embodiment> Next, a third embodiment of the present invention will be described. Here, the same components as those in the first embodiment are denoted by the same reference numerals, and the description thereof is omitted.

[0059] [3-1. Internal Module] For the internal module 120B of the radiation imaging apparatus (hereinafter, imaging apparatus 100B) according to the present embodiment, as shown in FIG. 6 for example, the first shield layer 4 or the second shield layer 8 also serves as the conductor layer L. That is, the wavelength λ of the electromagnetic wave and the distance d from the antenna 65b to the first shield layer 4 or the second shield layer 8 satisfy the relationship of 0 < d < Nλ + λ / 8, Nλ + 3λ / 8 < d < Nλ + 5λ / 8, or Nλ + 7λ / 8 < d < Nλ + 9λ / 8 (where N is an arbitrary integer of 0 or more).

[0060] [3-2. Third Embodiment and Others] When the first shield layer 4 or the second shield layer 8 also serves as the conductor layer L as in the present embodiment, the wavelength conversion unit 31B of the sensor panel 3B of the internal module 120B may be configured in the same manner as that of the sensor panel 3A described above.

[0061] [4. Fourth Embodiment] Next, a fourth embodiment of the present invention will be described. Here, the same components as those in the first embodiment are denoted by the same reference numerals, and the description thereof is omitted.

[0062] The internal module 120C of the radiation imaging apparatus (hereinafter, imaging apparatus 100C) according to the present embodiment is different from the first embodiment in that the sensor panel 3C has flexibility. The sensor panel 3C according to the present embodiment includes, for example, as shown in FIG. 7, a wavelength conversion unit 31C, a photoelectric conversion unit 32A, a moisture-proof layer 33, a second moisture-proof layer 34A, a third moisture-proof layer 35A, and a fourth moisture-proof layer 36A.

[0063] [4-1. Photoelectric Conversion Unit] The photoelectric conversion unit 32A according to the present embodiment has, in addition to the scanning line, signal line, switch element, and semiconductor element 322 (see FIG. 1) similar to those in the first embodiment, a substrate 321A and an element protection layer 323.

[0064] [4-1-1. Circuit Board] The substrate 321A is made of a flexible material and is formed into a rectangular plate shape similar to the substrate 321 according to the first embodiment. Specific examples of "flexible materials" include polyethylene naphthalate, polyethylene terephthalate (PET), polycarbonate, polyimide, polyamide, polyetherimide, aramid, polysulfone, polyethersulfone, fluororesin, polytetrafluoroethylene (PTFE), or composite materials thereof.

[0065] [4-1-2. Element protection layer] The element protection layer 323 covers the central portion of the imaging surface 321a (the region where the semiconductor element 322 is provided). The element protection layer 323 is formed in a sheet shape using a material that is capable of protecting the semiconductor element 322 and does not block the light arriving from the wavelength conversion section 31C. The element protection layer 323 according to this embodiment is made of at least one of an organic material and an inorganic material. Specific examples of organic materials include polymethylmethacrylate resin (PMMA), fluororesin, polyester resin, polyparaxylene, and the like. Specific examples of inorganic materials include nitride films such as SiN, silicon oxide, aluminum oxide, and ITO (Indium Tin Oxide). The element protection layer 323 may also function as a moisture-proof layer that prevents moisture from reaching the scintillator 311A ​​from the substrate 321A side.

[0066] [4-2. Wavelength conversion section] The wavelength conversion section 31C according to this embodiment includes a scintillator 311A, an optical adhesive layer 312, and a moisture-proof layer adhesive layer 313.

[0067] [4-2-1. Scintillator] The scintillator 311A ​​includes a deposition substrate 311a and a phosphor layer 311b.

[0068] The deposition substrate 311a is for supporting the phosphor layer 311b. The deposition substrate 311a according to this embodiment is made of a flexible material and has a rectangular plate shape similar to the deposition substrate according to the first embodiment. Materials that can be used to form the deposition substrate 311a are the same as those listed above as the materials for the substrate 321A of the photoelectric conversion section 32A. The deposition substrate 311a may be made of the same material as the substrate 321A, or may be made of a different material.

[0069] The phosphor layer 311b is similar to the phosphor layer according to the first embodiment.

[0070] [4-2-2. Optical adhesive layer] The optical adhesive layer 312 bonds the element protection layer 323 of the photoelectric conversion section 32A and the phosphor layer 311b together. The optical adhesive layer 312 is made of an optical adhesive. Specific examples of the optical adhesive include OCA (Optical Clear Adhesive) and hot melt resin. Specific examples of OCA include those containing at least one resin selected from the group consisting of acrylic resin, urethane resin, silicone resin, and fluororesin as a main component. Specific examples of hot melt resins include those containing at least one of polyolefin resin, polyamide resin, polyester resin, polyurethane resin, and acrylic resin as a main component. If there is no need to bond the element protection layer 323 and the phosphor layer 311b together (for example, if the scintillator 311A ​​is pressed against the photoelectric conversion section 32A by a moisture-proof layer 33 described later), the optical adhesive layer 312 is not necessary.

[0071] [4-2-3. Moisture-proof layer adhesive layer] The moisture-proof layer adhesive layer 313 bonds the moisture-proof layer 33 to at least one of the deposition substrate 311a and the phosphor layer 311b. The peripheral portion of the moisture-proof layer adhesive layer 313 bonds the moisture-proof layer 33 to at least one of the peripheral portion of the element protection layer 323 and the third moisture-proof layer 35A. The moisture-proof layer adhesive layer 313 is formed from an adhesive made of an organic material. Examples of organic materials include acrylic, urethane, polyester, styrene-isoprene-styrene block copolymer, natural rubber, butyl rubber, and epoxy.

[0072] [4-2-4. Wavelength conversion section and others] The wavelength converting section 31C may include a reflective layer. The reflective layer is for reflecting the light generated by the phosphor layer 311b. The reflective layer may be a film made of a metal (e.g., silver, aluminum, nickel, copper, etc.), or may be formed in a sheet shape from a resin mixed with particles of titanium oxide, aluminum oxide, etc. The reflective layer is disposed on the side of the scintillator 311A ​​where the front portion 11 of the housing 110 is present. As a result, light generated in phosphor layer 311b and traveling in a direction away from photoelectric conversion unit 32A (toward the reflective layer) is reflected by the reflective layer and travels toward photoelectric conversion unit 32A. As a result, more light generated in phosphor layer 311b reaches semiconductor element 322, improving the sensitivity of imaging device 100C.

[0073] [4-3. Moisture-proof layer] The moisture-proof layer 33 is intended to prevent the phosphor layer 311b of the scintillator 311A ​​from absorbing moisture. The moisture-proof layer 33 is formed in a sheet shape from a material that does not allow moisture to pass through. The moisture-proof layer 33 according to this embodiment is made of at least one of a metal, an inorganic material, and an organic material. Specific examples of metals include aluminum, silver, chromium, copper, nickel, titanium, magnesium, rhodium, lead, platinum, and gold. Specific examples of inorganic materials include oxides of the above metals, Al2O3, SiO2, and ITO. (Indium Tin Oxide), SiN, etc. Specific examples of organic materials include fluororesin, PVA, PVDC, PMMA, polyacrylonitrile (PAN), PLA resin (polylactic acid), polyparaxylene, and the like.

[0074] The center portion of the moisture-proof layer 33 covers the scintillator 311A. The center portion of the moisture-proof layer 33 according to this embodiment is attached to the scintillator 311A ​​by a moisture-proof layer adhesive layer 313. The peripheral edge of the moisture-proof layer 33 is attached by a moisture-proof layer adhesive layer 313 to the surface of at least one of the element protection layer 323 of the photoelectric conversion section 32A and the third moisture-proof layer 35A. If the housing 110 has a moisture-proof structure, the moisture-proof layer 33 and the moisture-proof layer adhesive layer 313 of the wavelength converting section 31C are not necessary.

[0075] [4-4. Second moisture-proof layer] The second moisture proof layer 34A covers the surface of the substrate 321A opposite to the surface on which the wavelength converting portion 31C is present. Materials that can be used to form the second moisture-proof layer 34A are similar to those listed as the materials for the moisture-proof layer 33 above. The second moisture-proof layer 34A may be made of the same material as the moisture-proof layer 33, or may be made of a different material.

[0076] [4-5. Third moisture-proof layer] The third moisture-proof layer 35A covers the peripheral portion of the imaging surface 321a (the area where the semiconductor element 322 is not provided). The third moisture proof layer 35A is formed in a sheet shape from a material that does not allow moisture to pass through. The third moisture proof layer 35A according to this embodiment is made of at least one of a metal, a composite material, and a resin material. Specific examples of metals include aluminum, copper, nickel, and lead. Specific examples of composite materials include glass, carbon, and CFRP. Specific examples of resin materials include PET, PC, PMMA, and ABS. The sensor panel 3C does not necessarily have to include the third moisture proof layer 35A.

[0077] [4-6. Fourth moisture-proof layer] The fourth moisture-proof layer 36A is intended to prevent the phosphor layer 311b of the scintillator 311A ​​from absorbing moisture. The fourth moisture-proof layer 36A is located inside the moisture-proof layer adhesive layer 313 and covers at least the surface of the scintillator 311A ​​that is aligned with the imaging surface 321a. The fourth moisture barrier layer 36A according to this embodiment further covers the side surfaces of the scintillator 311A. The fourth moisture barrier layer 36A may also cover the bottom surface of the scintillator 311A. The fourth moisture barrier layer 36A is formed in a sheet shape from a material that does not allow moisture to pass through. Like the moisture barrier layer 33, the fourth moisture barrier layer 36A according to this embodiment is made of at least one of a metal, an inorganic material, and an organic material. Specific examples of metals include aluminum, silver, chromium, copper, nickel, titanium, magnesium, rhodium, lead, platinum, and gold. Specific examples of inorganic materials include oxides of the above metals, Al2O3, SiO2, ITO (Indium Tin Oxide), SiN, and the like. Specific examples of organic materials include fluororesin, PVA, PVDC, PMMA, polyacrylonitrile (PAN), PLA resin (polylactic acid), and polyparaxylene. By using a combination of materials other than the inorganic or organic material selected for the moisture barrier layer 33, it is possible to prevent adverse effects such as corrosion and obtain complementary effects. For example, if the moisture barrier layer 33 is selected from an inorganic material, the fourth moisture barrier layer 36A should be selected from an organic material, and vice versa.

[0078] By providing the fourth moisture-proof layer 36A described above, the moisture resistance of the scintillator 311A ​​during handling is improved, and the moisture resistance of the final product is also improved. Although a double moisture-proof structure including the moisture-proof layer 33 and the fourth moisture-proof layer 36A has been described here, when the moisture-proof layer 33 is provided, it is not necessarily necessary to provide the fourth moisture-proof layer 36A.

[0079] [4-7. Fourth embodiment and others] The wavelength converting portion may include a reflective layer. The reflective layer is for reflecting the light generated by the phosphor layer 311b. The reflective layer may be a film made of a metal (e.g., silver, aluminum, nickel, copper, etc.), or may be formed in a sheet shape from a resin mixed with particles of titanium oxide, aluminum oxide, etc. The reflective layer is disposed on the side of the scintillator 311A ​​where the front portion 11 of the housing 110 is present. As a result, light generated in phosphor layer 311b and traveling in a direction away from photoelectric conversion unit 32A (toward the reflective layer) is reflected by the reflective layer and travels toward photoelectric conversion unit 32A. As a result, more light generated in phosphor layer 311b reaches semiconductor element 322, improving the sensitivity of imaging device 100C.

[0080] Furthermore, a second shield layer 8 is disposed between the front surface 11 of the housing 110 and the third moisture-proof layer 35A of the sensor panel 3C (on the surface of the third moisture-proof layer 35A), if necessary. The third moisture proof layer 35A and the second shield layer 8 may be integrally formed from the same material (may be made into a common material). Furthermore, if the fourth moisture-proof layer 36A has a sufficient moisture-proof effect and a member also serving as the conductor layer L is provided separately from the moisture-proof layer 33, the moisture-proof layer 33 does not necessarily need to be provided.

[0081] <5. Actions and Effects> The imaging devices 100, 100A, 100B, and 100C described above include a sensor panel 3, 3A having an imaging surface 321a on which a plurality of semiconductor elements 322 are arranged in a two-dimensional distribution, a communication unit 65 having an antenna 65b and performing wireless communication with other devices, and a conductor layer L (first and second shield layers 4, 8, moisture-proof layers 33, 36A, front portion 11, back portion 21) that extends along the imaging surface 321a and reflects the electromagnetic waves emitted by the antenna 65b. The wavelength λ of the electromagnetic waves and the distance d from the antenna 65b to the plane P including the conductor layer L satisfy the relationship of 0 < d < Nλ + λ / 8, Nλ + 3λ / 8 < d < Nλ + 5λ / 8, or Nλ + 7λ / 8 < d < Nλ + 9λ / 8 (where N is an arbitrary integer greater than or equal to 0).

[0082] When the antenna 65b and the conductor layer L are in the above-described positional relationship, when the antenna 65b emits electromagnetic waves, the electromagnetic waves traveling from the antenna 65b to the conductor layer L (progressive wave E1) and the electromagnetic waves reflected by the conductor layer L (reflected wave E2) interfere with each other to form a standing wave. And at the nodes N of this standing wave and in the vicinity thereof (within the range of λ / 8, 3λ / 8 to 5λ / 8, 7λ / 8 to 9λ / 8... from the conductor layer L), the electromagnetic waves are reduced. This canceling effect increases as the intensity of the reflected wave E2 increases. However, since the conductor layer L according to the present embodiment has a thickness (9 μm or more) that can sufficiently reflect electromagnetic waves, more electromagnetic waves can be canceled. Further, the conductor layer L is the moisture-proof layer 33, 36A, the front portion 11, the back portion 21, the first shield layer 4, or the second shield layer 8, which are members that the radiation imaging device conventionally includes. Therefore, according to the imaging devices 100, 100A, 100B, and 100C, the electric field generated in the vicinity of the antenna 65b can be reduced without adding new components. As a result, while reducing the adverse effects on the human body in contact with the imaging devices 100, 100A, 100B, and 100C, image data and the like can be transmitted over a long distance.

[0083] Further, in the imaging devices 100, 100C according to the first and fourth embodiments, the moisture-proof layer 33 of the scintillator 311 also serves as the conductor layer L. Therefore, imaging devices 100 and 100C can simultaneously solve two completely different problems, namely, reducing the electric field generated near antenna 65b and preventing the scintillator from absorbing moisture, without adding any new components.

[0084] Furthermore, in the imaging device 100C according to the fourth embodiment, the sensor panel 3C is flexible. Therefore, according to the imaging device 100C, the sensor panel can be made lighter and less susceptible to damage due to impact, compared to a case in which the substrate of the sensor panel is made of glass. In the imaging devices 100 and 100C according to the first and fourth embodiments, the moisture-proof layer 33 is made of aluminum foil. Aluminum has low electrical conductivity and is lightweight, so that the imaging devices 100 and 100C can more reliably reduce the electric field generated near the antenna 65b while reducing the weight of the conductor layer L and therefore the imaging device 100. Furthermore, aluminum has high malleability, so that the imaging devices 100 and 100C can provide the moisture-proof layer 33 with high flexibility, and can continue to protect the scintillator from moisture even if the flexible sensor panel is bent.

[0085] <6. Other aspects of the present invention> The present invention has been described above based on an embodiment, but it goes without saying that the present invention is not limited to the above embodiment, and can be modified as appropriate without departing from the spirit of the present invention.

[0086] For example, the wavelength conversion section 31 according to the first embodiment may include at least any one of the optical adhesive layer 312, the third moisture-proof layer 35A, and the moisture-proof layer adhesive layer 313 described in the second embodiment. Furthermore, the photoelectric conversion section 32A according to the first embodiment may include at least any one of the element protection layer 323, the moisture-proof layer 33, and the second moisture-proof layer 34A described in the second embodiment. [Explanation of symbols]

[0087] 100, 100A, 100B, 100C Radiation imaging device 110,110A Housing 1,1A box body 11 Front part 11A Front part (conductor layer) 11a Radiation entrance surface 12 Side part 12A Side part (conductor layer) 2 Lid 21,21A Back part 120,120A,120B,120C Internal Module 3,3A,3B,3C Sensor Panel 31, 31A, 31B, 31C Wavelength conversion section 311,311A Scintillator 311a Deposition substrate 311b Phosphor layer 312 Optical adhesive layer 313 Moisture-proof layer adhesive layer 32,32A Photoelectric conversion unit 321,321A Board 321a Imaging surface 322 Semiconductor Devices 323 Element protection layer 33 Moisture barrier 34A Second moisture barrier 35A Third moisture-proof layer 36A Fourth moisture barrier 4 First Shield Layer 5 Base 6. Electronic Components 61 Scanning unit 61 Communications Department 62 Readout section 63 Control Unit 64 Power supply section 65 Communications Department 65a Communication Circuit 65b Antenna 65c Connector 7 Radiation attenuation layer 8 Second Shield Layer E standing wave E1 traveling wave E2 reflected wave L Conductor layer N section P Plane including conductor layer L d Distance from the antenna to the plane including the conductor layer λ Wavelength of electromagnetic wave

Claims

1. a sensor panel having an imaging surface on which a plurality of semiconductor elements are arranged so as to be distributed two-dimensionally; a communication unit having an antenna and performing wireless communication with another device; a conductor layer extending along the imaging surface and reflecting electromagnetic waves emitted by the antenna; A radiation imaging device in which the wavelength λ of the electromagnetic wave and the distance d from the antenna to a plane including the conductor layer satisfy the relationship 0<d<Nλ+λ / 8, Nλ+3λ / 8<d<Nλ+5λ / 8, or Nλ+7λ / 8<d<Nλ+9λ / 8 (where N is any integer equal to or greater than 0).

2. the sensor panel includes a scintillator and a moisture-proof layer that covers the scintillator to prevent moisture from reaching the scintillator; The radiation imaging apparatus according to claim 1 , wherein the moisture-proof layer also serves as the conductor layer.

3. The radiation imaging apparatus according to claim 1 , wherein the sensor panel is flexible.

4. 3. The radiation imaging apparatus according to claim 2, wherein the moisture-proof layer is an aluminum foil.

5. The radiation imaging apparatus according to claim 1 , wherein the communication unit performs wireless communication using the electromagnetic waves in a 2.4 GHz band.

6. The radiation imaging apparatus according to claim 1 , wherein the communication unit performs wireless communication using the electromagnetic waves in a 5 GHz band.

7. 5. The radiation imaging apparatus according to claim 4, wherein the aluminum foil has a thickness of 10 um or more.

8. The radiation imaging apparatus according to claim 5 , wherein the communication unit is connectable to a wireless LAN that uses electromagnetic waves in a 2.4 GHz band.

9. The radiation imaging apparatus according to claim 6 , wherein the communication unit is connectable to a wireless LAN that uses electromagnetic waves in a 5 GHz band.

Images