JP7625738B2 - Radiation imaging panel, radiation imaging device, radiation imaging system, method for manufacturing radiation imaging panel, and scintillator plate - Google Patents

Description

The present invention relates to a radiation imaging panel, a radiation imaging device, a radiation imaging system, a method for manufacturing a radiation imaging panel, and a scintillator plate.

As a flat panel detector (FPD) used for radiography in medical image diagnosis and non-destructive testing, there is an indirect conversion type FPD in which radiation passing through a subject is converted into light by a scintillator and the light emitted by the scintillator is detected by a photoelectric conversion element. For the scintillator that converts radiation into light, columnar crystals of alkali metal halide compounds such as cesium iodide are widely used to efficiently transmit the light converted from radiation to the photoelectric conversion element. Since the alkali metal halide compounds deteriorate due to moisture absorption, a protective layer with a moisture-proof function may be arranged on the scintillator. In addition, a reflective layer with a light-reflecting function may be arranged on the opposite side of the scintillator from the photoelectric conversion element so that the light converted from radiation by the scintillator is efficiently detected by the photoelectric conversion element. Patent Document 1 shows a radiation detection device in which a phosphor protective layer with a light-reflecting function and a moisture-proof function made of a resin containing light-reflective fine particles is formed on a phosphor layer and embedded between the columns of the phosphor columnar crystals.

JP 2006-052980 A

The concentration distribution of the light-reflective particles shown in Patent Document 1 needs to be examined. Specifically, between each columnar crystal of the scintillator, light-reflective particles must be arranged so that light does not enter adjacent columnar crystals in order to improve the MTF (Modulation Transfer Function). On the other hand, when light-reflective particles are present at the top of the columnar crystals, the light emitted upward from the columnar crystal of the scintillator is reflected by the light-reflective particles and re-enters the columnar crystal, which can improve the DQE (Detective Quantum Efficiency). However, there is a possibility that the light emitted upward from the columnar crystal is diffused by the light-reflective particles, and the effect of improving the MTF cannot be obtained.

The present invention aims to provide a technology that is advantageous for improving the MTF in radiation imaging panels.

In view of the above problems, a radiation imaging panel according to an embodiment of the present invention is a scintillator plate for detecting radiation, comprising a scintillator having a plurality of columnar crystals that convert the radiation into visible light, a plate-shaped base material, and a thermoplastic resin material that covers the tip sides of adjacent columnar crystals among the plurality of columnar crystals to position metal particles in a first region between the adjacent columnar crystals, and is located in a second region between the scintillator and the base material to bond the scintillator to the base material, wherein the first region is a region in which metal particles are arranged, and the second region is a region in which the metal particles are arranged at a lower concentration than in the first region, or the second region is a region in which the metal particles are not arranged.

The above means provide technology that is advantageous for improving the MTF in radiation imaging panels.

FIG. 2 is a cross-sectional view showing an example of the configuration of a radiation imaging panel according to the present embodiment. FIG. 2 is a diagram showing the configuration of the radiation imaging panel shown in FIG. 1 . FIG. 2 is a diagram showing the configuration of a comparative example of the radiation imaging panel of FIG. 1 . FIG. 2 is a diagram showing the configuration of the radiation imaging panel shown in FIG. 1 . FIG. 2 is a diagram showing the configuration of a comparative example of the radiation imaging panel of FIG. 1 . 2 is a graph showing characteristics of the radiation imaging panel shown in FIG. 1; 2 is a diagram showing an example of the configuration of a radiation imaging apparatus and a radiation imaging system using the radiation imaging panel of FIG. 1;

The following embodiments are described in detail with reference to the attached drawings. Note that the following embodiments do not limit the invention according to the claims. Although the embodiments describe multiple features, not all of these multiple features are necessarily essential to the invention, and multiple features may be combined in any manner. Furthermore, in the attached drawings, the same reference numbers are used for the same or similar configurations, and duplicate explanations are omitted.

In addition, radiation in this invention may include alpha rays, beta rays, gamma rays, and other beams made of particles (including photons) emitted by radioactive decay, as well as beams with the same or greater energy, such as X-rays, particle beams, and cosmic rays.

The configuration and manufacturing method of the radiation imaging panel according to this embodiment will be described with reference to Figures 1 to 7. Figure 1 is a diagram showing the cross-sectional structure of a radiation imaging panel 100 according to this embodiment. The radiation imaging panel 100 includes a substrate 101 including a pixel region 110 in which a plurality of pixels each including a photoelectric conversion element is arranged on a main surface 109, a scintillator 107 including a plurality of columnar crystals 102 arranged on the main surface 109 of the substrate 101, and a protective layer 108 including a resin layer 103 arranged so as to cover the scintillator 107. A planarization layer 105 may be arranged between the substrate 101 and the scintillator 107 to reduce steps caused by transistors, wiring layers, etc. formed on the main surface 109 of the substrate 101.

In the pixel region 110, a plurality of pixels may be arranged in a two-dimensional array. For example, 3300 x 2800 pixels may be arranged on a substrate 101 of 550 mm x 445 mm. Of the 3300 x 2800 pixels, 10 pixels arranged on the outer periphery may be a dummy pixel region, and the effective pixel region of the pixel region 110 may be constituted by 3280 x 2780 pixels arranged inside the dummy pixels. The number of pixels arranged in the pixel region 110 and the number of pixels arranged in the effective pixel region of the pixel region 110 may be set appropriately depending on the size of the substrate 101, the subject to be imaged, etc.

In addition, the pixel region 110 provided on the substrate 101 may be provided with column signal lines for extracting signals generated in each pixel, row signal lines for driving each element including the pixels arranged in the pixel region 110, and the like. The column signal lines and row signal lines may be electrically connected to the readout circuit board and the drive circuit board, respectively, via a flexible wiring board or the like. The substrate 101 may be provided with a connection terminal portion (not shown) for connecting the column signal lines and row signal lines to the readout circuit board and the drive circuit board. The signals generated in each pixel of the pixel region 110 may be output from the radiation imaging panel 100 via the connection terminal portion.

Here, an example is shown in which the readout circuit and the drive circuit are arranged outside the radiation imaging panel 100, but the readout circuit and the drive circuit may be arranged in the radiation imaging panel 100. Even in this case, a connection terminal portion (not shown) is arranged on the substrate 101, and a signal generated in each pixel of the pixel region 110 can be output from the radiation imaging panel 100 via the connection terminal portion (not shown).

In this embodiment, the protective layer 108 includes a base 106 disposed on the side of the resin layer 103 opposite the scintillator 107, and a metal layer disposed between the resin layer 103 and the base 106. For example, the protective layer 108 may be produced by forming an aluminum metal layer 104 on the base 106, and forming a resin layer 103 on the metal layer 104.

The scintillator 107 converts radiation incident on the scintillator 107 into light that can be detected by a photoelectric conversion element provided on the substrate 101. For example, the scintillator 107 can convert radiation into visible light. For the scintillator 107, an alkali metal halide compound such as cesium iodide (CsI) that grows columnar crystals can be used. When CsI is used as the scintillator 107, thallium iodide (TlI) can be used as an activator.

The scintillator 107 can be formed, for example, by using a vapor deposition method. The substrate 101 is placed in a vapor deposition apparatus so that the planarization layer 105 becomes the deposition surface, and CsI and TlI are each filled into a cell container so that the Tl concentration is 1 mol % relative to CsI, and co-deposition is performed by heating. This forms the scintillator 107, which includes multiple columnar crystals 102.

A resin layer 103 is formed on the scintillator 107. The scintillator 107, which is composed of a plurality of columnar crystals 102 containing an alkali metal halide compound, deteriorates due to moisture absorption. Therefore, the resin layer 103 may also function as a moisture-proof layer for the scintillator 107. By providing the resin layer 103 that covers the scintillator 107 with the function of a moisture-proof layer, it becomes possible to prevent the scintillator 107 from deteriorating due to moisture absorption.

2(a) is an enlarged view of part 111 in FIG. 1. A hot melt resin mainly composed of polyolefin resin may be used for the resin layer 103. Hot melt resin is defined as an adhesive resin that does not contain water or solvent, is solid at room temperature, and is composed of 100% non-volatile thermoplastic material (Thomas P. Flanagan, Adhesives Age, vol. 9, No. 3, pp. 28 (1966)). Hot melt resin has the property of melting when the resin temperature rises and solidifying when the resin temperature drops, and has adhesive properties to other organic materials and inorganic materials in a heated and molten state, but is in a solid state at room temperature and has no adhesive properties. In addition, since the hot melt resin does not contain polar solvents, solvents, or water, even if it comes into contact with the scintillator 107 having columnar crystals 102 of an alkali halide, the scintillator 107 will not dissolve, and the hot melt resin can also function as a protective layer.

Hot melt resins are classified according to the type of base polymer (base material) that is the main component, and polyolefin, polyester, polyamide, etc. can be used. When using a hot melt resin in the resin layer 103 as the protective layer 108 for the scintillator 107, it is important that the resin layer 103 has high moisture resistance and high optical transparency for transmitting visible light generated by the scintillator 107.

The material used for the resin layer 103 is not limited to hot melt resin. For example, a resin having a pressure-sensitive adhesive action due to intermolecular forces, a so-called adhesive material, may be used for the resin layer 103. In this case, a urethane resin or an acrylic resin may be used for the resin layer 103. For example, a polymethyl methacrylate resin, which is an acrylic resin, may be used for the resin layer 103.

The region between the main surface 109 of the substrate 101 and the upper surface 203 of the resin layer 103 shown in FIG. 1 and FIG. 2(a) is defined as follows. The region between adjacent columnar crystals 102 of the scintillator 107 is defined as a first region 211. The region between the columnar crystals 102 and the first region 211 and the upper surface 203 of the resin layer 103, in which the resin layer 103 is arranged, is defined as a second region 212. Here, the first region 211 is defined as a region in which the ratio of the columnar crystals 102 of the scintillator 107 to the surface parallel to the main surface 109 of the substrate 101 is 75% or more and 98% or less. In this first region 211, particles 201 of a metal compound are arranged as shown in FIG. 2(a).

Figure 3 shows a cross-sectional view of a radiation imaging panel 300 of the comparative example. In the radiation imaging panel 300 of the comparative example, since no metal compound particles are arranged in the first region 211, the light emitted from the columnar crystals 102 of the scintillator 107 may spread laterally in the drawing in the first region 211. As a result, repeated reflection and refraction in the first region 211 may promote light scattering and attenuation of light that occurs at the same time, and the MTF may decrease.

In contrast, in this embodiment, as shown in FIG. 2(a), metal compound particles 201 are arranged in the first region 211. By arranging the metal compound particles 201, the light emitted from the columnar crystals 102 is more likely to be reflected by the columnar crystals 102 from which it was emitted again. As a result, light scattering in the first region 211 is suppressed, and the MTF can be improved.

The metal compound particles 201 may be metal oxide particles. A material having a refractive index larger than that of the scintillator 107 may be used for the metal compound particles 201. For example, when the above-mentioned CsI (refractive index (n): 1.78 to 1.84 (depending on the type of activator, etc.)) is used as the scintillator 107 of the alkali metal halide compound, a material having a refractive index larger than that of CsI may be used. For example, the metal compound particles 201 may be white lead (2PbCo _3.Pb (OH) ₂ ) (n: 1.94 to 2.09), zinc oxide (n: 2.0), yttrium oxide (n: 1.91), zirconium oxide (n: 2.20), titanium oxide (n: 2.50 to 2.72), or the like. For example, the refractive index of the metal compound particles 201 may be 1.94 or more and 2.72 or less. In addition, for example, rutile-type titanium dioxide particles, which have a high refractive index among titanium oxides, may be used as the metal compound.

Furthermore, the metal compound particles 201 may have a higher refractive index than the resin constituting the resin layer 103. By increasing the difference between the refractive index of the metal compound particles 201 and the refractive index of the resin layer 103, light is more likely to be reflected on the surface of the metal compound particles 201 in the first region 211. The refractive index of the above-mentioned hot melt resin is about 1.52, the refractive index of the urethane resin is about 1.49, and the refractive index of the acrylic resin is about 1.49 to 1.53.

The average particle size of the metal compound particles 201 may be 200 nm or more and 500 nm or less. Generally, the sensitivity characteristic of a photoelectric conversion element is 500 nm to 800 nm, but if the particle is 1/2 the wavelength of light or less, the effect of Rayleigh scattering appears, and the probability of reflection in the direction of the incident light increases. For example, rutile-type titanium dioxide particles having an average particle size of 250 nm and a particle size distribution of 10% diameter D ₁₀ = 195 nm, 50% diameter (median diameter) D ₅₀ = 245 nm, and 90% diameter D ₉₀ = 275 nm may be used as the metal oxide particles 201.

In the configuration shown in FIG. 2(a), a part of the resin layer 103 is disposed in the first region 211. In addition, in the first region 211, metal compound particles 201 are disposed in the resin layer 103. However, as shown in FIG. 2(b), the resin layer 103 does not have to be disposed in the first region 211. By not disposing the resin layer 103 in the first region 211, the refractive index of the space (air layer) in the first region 211 is lowered. This increases the refractive index difference between the air layer in the first region 211 and the columnar crystals 102, making it difficult for light to be emitted from the columnar crystals 102. In addition, the refractive index difference between the air layer in the first region 211 and the particles of the metal compound particles 201 increases, and the light that has been emitted from the columnar crystals 102 can be more efficiently reflected by the metal compound particles 201. This can further improve the MTF.

In the configuration shown in Figures 2(a) and 2(b), the metal compound particles 201 are not arranged in the second region 212. However, as shown in Figure 4, the metal compound particles 201 may be arranged in the second region 212. In this case, as shown in Figure 4, the metal compound particles 201 may be dispersed in the portion of the resin layer 103 that is arranged in the second region 212.

Here, the concentration of the metal compound particles 201 arranged in the second region 212 relative to the resin layer 103 will be considered. FIG. 4 shows the radiation imaging panel 100 of this embodiment in which the metal compound particles 201 are added to the second region 212 at a concentration lower than that of the first region 211. FIG. 5 shows a radiation imaging panel 500 of a comparative example in which the concentration of the metal compound particles 201 in the second region 212 is equal to or higher than the concentration of the metal compound particles 201 arranged in the first region 211. When the concentration of the metal compound particles 201 in the second region 212 is high, scattering in the film thickness direction (vertical direction in FIG. 5) of the resin layer 103 increases. Therefore, the amount of light returning to the columnar crystal 102 increases. However, the light reflected by the metal compound particles 201 arranged in the second region 212 may be incident on another columnar crystal 102 without being reflected by the columnar crystal 102 that emitted the light. In other words, light is diffused, which can cause a decrease in MTF.

Figure 6 shows the MTF value at 2 lp/mm of a radiation imaging panel manufactured by changing the concentration of the metal compound particles 201 in the resin layer 103 in the second region 212. Since it is difficult to mix the metal compound particles 201 with more than 90 vol% in the resin constituting the resin layer 103, the maximum concentration of the metal compound particles 201 in the resin layer 103 is 90 vol%. The MTF value was measured by irradiating X-rays conforming to the radiation quality RQA5 of the international standard. Also, Figure 6 shows a case where the metal compound particles 201 are arranged at the same concentration in the first region 211 and the second region 212 (radiation imaging panel 500 of the comparative example) and a case where the metal compound particles 201 are arranged at a lower concentration in the second region 212 than in the first region 211 (radiation imaging panel 100 of the present embodiment).

As shown in FIG. 6, the radiation imaging panel 100 of this embodiment, in which the metal compound particles 201 are added to the second region 212 at a lower concentration than the first region 211, has an improved MTF value compared to the radiation imaging panel 500 of the comparative example, in which the metal compound particles 201 are added to the first region 211 and the second region 212 at the same concentration.

6, in the second region 212, when the concentration of the metal compound particles 201 in the resin layer 103 is increased from 0 vol%, the MTF improves, and at an appropriate concentration, the MTF shows an optimal value, and when the concentration is further increased, the MTF decreases. More specifically, when the concentration of the metal compound particles 201 in the resin layer 103 in the second region 212 is 0.15 vol% or more and less than 7.5 vol%, the MTF value improves. When the concentration of the metal compound particles 201 in the second region 212 is lower, the possibility of light reflection by the metal compound particles 201 in the second region 212 of the resin layer 103 is lower than when the concentration is high, and scattering is suppressed. In addition, by the presence of an appropriate amount of the metal compound particles 201, the light reflected by the metal compound particles 201 is attenuated while diffusing, and does not return to the columnar crystals 102. As a result, the radiation imaging panel 100 of this embodiment can improve the MTF.

That is, as shown in FIG. 4, when the metal compound particles 201 are arranged in the second region 212, the metal compound particles 201 may be arranged in the second region 212 at a lower concentration than in the first region 211. This can improve the MTF in the radiation imaging panel 100. Furthermore, in this case, the concentration of the metal compound particles 201 in the second region 212 in the resin layer 103 may be 0.15 vol% or more and less than 7.5 vol%. This can further improve the MTF in the radiation imaging panel 100.

In this way, when the first region 211 contains metal compound particles 201 and the second region 212 contains metal compound particles 201 at a concentration lower than that of the first region 211, or when the second region 212 does not contain metal compound particles 201, the MTF can be improved. This allows for the realization of a radiation imaging panel 100 with high spatial resolution.

Next, a method for manufacturing a radiation imaging panel 100 in which the concentration of the metal compound particles 201 differs between the first region 211 and the second region 212 will be described. First, as the substrate 101, for example, an alkali-free glass having a size of 550 mm×445 mm and a thickness of 500 μm is prepared. The substrate 101 is not limited to glass, and may be a resin substrate or a semiconductor substrate such as silicon. The pixel region 110 is formed by repeatedly performing a film formation process for forming a semiconductor layer such as silicon (e.g., amorphous silicon) and a metal (e.g., aluminum) constituting a wiring layer on the glass substrate 101, a photolithography process, an etching process, and the like. In the pixel region 110, a plurality of pixels each including a photoconversion element that generates a charge according to the light emission of the scintillator 107 and a switching element that outputs a signal according to the generated charge are arranged. In addition, a connection terminal portion (not shown) for driving the pixel and sending the obtained signal to an external circuit may be formed in the pixel region 110.

After forming the pixel region 110, an array test may be performed to check the operation of the pixels formed in the pixel region 110. After confirming that the operation is good and there are no or only a few missing pixels in the array test, the periphery of the substrate 101 may be masked with a masking film to protect the connection terminal portion (not shown), and the planarization layer 105 may be formed. The planarization layer 105 may be formed, for example, by placing the substrate 101 in a spray spin coater, spinning it at about 100 rpm while spraying a polyimide solution, and then drying and dry annealing it at a temperature of 220°C. For example, the planarization layer 105 may have a thickness of about 2 μm.

After preparing the substrate 101 on which the pixel region 110 is formed, the scintillator 107 is then formed. First, a deposition mask is set on the region of the substrate 101 on which the planarization layer 105 is formed where the scintillator 107 is not to be formed, and then the substrate 101 is placed on a deposition apparatus so that the planarization layer 105 is the deposition surface. Then, CsI and TlI are filled in a cell container so that the Tl concentration is 1 mol% relative to CsI, and co-deposition is performed by heating. The scintillator 107 may have a thickness of, for example, 380 μm and a film filling rate of 75%. At this time, the outer edge of the scintillator 107 may be disposed outside the outer edge of the pixel region 110. In addition, when performing deposition of the scintillator 107, the deposition apparatus may be evacuated to the 10 ⁻³ Pa range, and then heated with a lamp heater so that the substrate surface is at 175° C.

After the scintillator 107 is formed, the particles 201 of the metal compound are scattered from above the scintillator 107 so that the particles 201 of the metal compound enter between the columnar crystals 102 of the scintillator 107. Next, a sheet of hot-melt resin constituting the resin layer 103 is placed on the scintillator 107, and the two are bonded together using a vacuum thermal transfer device or the like, thereby producing the radiation imaging panel 100 shown in FIG. 2(b). For example, the scintillator 107 and the sheet of hot-melt resin are first brought into contact with each other at 30° C., and then the pressure is reduced to 10 ⁻¹ Pa to remove air bubbles. Furthermore, pressure is applied between the substrate 101 and the sheet of hot-melt resin constituting the resin layer 103, and the two are heated to 70 to 100° C. and held for an appropriate time, whereby the substrate 101 on which the scintillator 107 is formed and the resin layer 103 constituting the protective layer 108 are bonded together.

For example, after the scintillator 107 is formed, a resin to which metal compound particles 201 are added may be applied so as to cover the scintillator 107, thereby forming a portion of the resin layer 103 to be disposed in the first region 211. Next, a sheet of hot melt resin or a sheet containing a urethane resin or an acrylic resin, which is called an adhesive having a pressure-sensitive adhesive action due to the above-mentioned intermolecular force, is attached to the resin formed using the coating method. In this way, a portion of the resin layer 103 to be disposed in the second region 212 is formed. At this time, the resin attached to the resin formed using the coating method may contain metal compound particles 201 added at a concentration lower than that of the resin formed using the coating method. In this way, the radiation imaging panel 100 shown in FIG. 4 can be produced. In addition, the resin attached to the resin formed using the coating method may not contain metal compound particles 201. In this way, the radiation imaging panel 100 shown in FIG. 2(a) can be produced.

The first region 211 of the resin layer 103 is not limited to being formed using a coating method. The portion of the resin layer 103 in the first region 211 that contacts the columnar crystals 102 may be formed by laminating resin to which metal compound particles 201 have been added using a vacuum thermal transfer device or the like.

After forming the resin layer 103, a metal layer 104 such as aluminum or a base 106 may be formed on the resin layer 103. The above-mentioned hot melt resin sheet or a sheet containing a urethane resin or an acrylic resin called an adhesive may be produced by forming a metal layer 104 such as aluminum on the base 106 and forming a resin on the metal layer 104. A PET substrate or the like may be used for the base 106. For example, a metal layer 104 of aluminum having a thickness of 12 μm may be formed on a base 106 of PET having a thickness of 30 μm, and a resin layer 103 or a part of the resin layer 103 may be formed on the metal layer 104. By bonding the resin layer 103 formed on the base 106 to the scintillator 107, a radiation imaging panel 100 having a protective layer 108 as shown in FIG. 1 can be produced.

In addition, in this embodiment, the case where the substrate 101 having the pixel region 110 in which a plurality of pixels are arranged is described, but the present invention is not limited to this. For example, the substrate 101 may not have the pixel region 110. In this case, the reference numeral 100 may be called a scintillator plate. For example, by mounting this scintillator plate on a sensor substrate having a pixel region in which a plurality of pixels are arranged, the substrate 101 may function as a radiation imaging panel. Therefore, when the substrate 101 does not have the pixel region 110, the substrate 101 may be a transparent substrate that transmits light emitted by the scintillator 107.

Below, a radiation imaging device incorporating the above-mentioned radiation imaging panel 100 and a radiation imaging system 800 using a radiation imaging device incorporating the radiation imaging panel 100 will be described with reference to FIG. 7.

The radiation imaging system 800 is configured to electrically capture an optical image formed by radiation and obtain an electrical radiation image (i.e., radiation image data). The radiation imaging system 800 includes, for example, a radiation imaging device 801, an exposure control unit 802, a radiation source 803, and a computer 804.

The radiation source 803 for irradiating the radiation imaging device 801 with radiation starts irradiating radiation in accordance with an exposure command from the exposure control unit 802. The radiation emitted from the radiation source 803 passes through a subject (not shown) and is irradiated to the radiation imaging device 801. The radiation source 803 stops emitting radiation in accordance with a stop command from the exposure control unit 802.

The radiation imaging device 801 includes the radiation imaging panel 100 described above, a control unit 805 for controlling the radiation imaging panel 100, and a signal processing unit 806 for processing a signal output from the radiation imaging panel 100. The signal processing unit 806 may, for example, perform A/D conversion of the signal output from the radiation imaging panel 100 and output it to the computer 804 as radiation image data. The signal processing unit 806 may also generate a stop signal for stopping the irradiation of radiation from the radiation source 803 based on the signal output from the radiation imaging panel 100. The stop signal is supplied to the exposure control unit 802 via the computer 804, and the exposure control unit 802 sends a stop command to the radiation source 803 in response to the stop signal.

The control unit 805 can be configured, for example, by a PLD (Programmable Logic Device) such as an FPGA (Field Programmable Gate Array), or an ASIC (Application Specific Integrated Circuit), or a general-purpose computer with an embedded program, or a combination of all or part of these.

In addition, in this embodiment, the signal processing unit 806 is shown as being arranged in the control unit 805 or as being a part of the function of the control unit 805, but this is not limited to the above. The control unit 805 and the signal processing unit 806 may each have a separate configuration. Furthermore, the signal processing unit 806 may be arranged separately from the radiation imaging device 801. For example, the computer 804 may have the function of the signal processing unit 806. Therefore, the signal processing unit 806 may be included in the radiation imaging system 800 as a signal processing device that processes the signal output from the radiation imaging device 801.

The computer 804 can control the radiation imaging device 801 and the exposure control unit 802, receive radiation image data from the radiation imaging device 801, and perform processing to display the data as a radiation image. The computer 804 can also function as an input unit for the user to input conditions for capturing a radiation image.

As an example, the exposure control unit 802 has an exposure switch, and when the user turns on the exposure switch, it sends an exposure command to the radiation source 803 and also sends a start notification indicating the start of radiation emission to the computer 804. In response to the start notification, the computer 804 notifies the control unit 805 of the radiation imaging device 801 of the start of radiation irradiation. In response to this, the control unit 805 causes the radiation imaging panel 100 to generate a signal corresponding to the incident radiation.

The invention is not limited to the above-described embodiment, and various modifications and variations are possible without departing from the spirit and scope of the invention. Therefore, the following claims are appended to disclose the scope of the invention.

100: Radiation imaging panel, 101: Substrate, 102: Columnar crystals, 103: Resin layer, 107: Scintillator, 108: Protective layer, 109: Main surface, 201: Metal compound particles, 203: Top surface, 211: First region, 212: Second region

Claims (18)

A scintillator plate for detecting radiation, comprising:
a scintillator having a plurality of columnar crystals for converting the radiation into visible light;
A plate-shaped substrate;
a thermoplastic resin material that covers tip sides of adjacent columnar crystals among the plurality of columnar crystals to position metal particles in a first region between the adjacent columnar crystals, and that is positioned in a second region between the scintillator and the base material to bond the scintillator to the base material,
the first region is a region in which the metal particles are arranged,
A scintillator plate characterized in that the second region is a region in which the metal particles are arranged at a lower concentration than the first region, or the second region is a region in which the metal particles are not arranged. 2. The scintillator plate according to claim 1, wherein the resin material is not disposed in the first region. 2. The scintillator plate according to claim 1, wherein a portion of the resin material is disposed in the first region. 4. The scintillator plate according to claim 1, wherein the concentration of the metal particles added to the resin material in the second region is equal to or greater than 0.15 vol % and less than 7.5 vol %. 5. The scintillator plate according to claim 1, wherein the metal particles are dispersed in a portion of the resin material that is disposed in the second region. 6. The scintillator plate according to claim 1, wherein the metal particles have a refractive index higher than a refractive index of a resin constituting the resin material. 7. The scintillator plate according to claim 1, wherein the metal particles contain a metal oxide as a material . 8. The scintillator plate according to claim 1, wherein the metal particles contain rutile titanium dioxide as a material . 9. The scintillator plate according to claim 1, wherein the plurality of columnar crystals contain an alkali metal halide compound as a material . A scintillator plate as described in any one of claims 1 to 9, characterized in that the resin material contains at least one of a resin composed of a non-volatile thermoplastic material and a resin having a pressure-sensitive adhesive effect due to intermolecular forces. 11. The scintillator plate according to claim 1 , wherein the first region is located at a position where the cross section of the plurality of columnar crystals occupies 75% or more and 98% or less of the cross section. 12. The scintillator plate according to claim 1, wherein the average particle size of the metal particles is 200 nm or more and 500 nm or less. 13. A scintillator plate according to any one of the preceding claims , wherein the substrate comprises a metal layer . 14. A scintillator plate according to any one of claims 1 to 13, characterized in that the substrate comprises a PET layer. A radiation imaging panel comprising the scintillator plate according to any one of claims 1 to 14 ;
a control unit for controlling the radiation imaging panel;
13. A radiation imaging apparatus comprising: The radiation imaging apparatus according to claim 15 ,
a signal processing device for processing a signal output from the radiation imaging device;
1. A radiation imaging system comprising: Providing a scintillator having a plurality of columnar crystals for converting radiation into visible light;
disposing metal particles between the plurality of columnar crystals;
a step of bringing a thermoplastic resin into contact with the scintillator and heating the thermoplastic resin to cover tip sides of adjacent columnar crystals among the plurality of columnar crystals, thereby positioning metal particles in a first region between the adjacent columnar crystals and in a second region between the scintillator and the substrate, thereby bonding the scintillator and the substrate,
the first region is a region in which the metal particles are arranged,
A method for manufacturing a scintillator plate, characterized in that the second region is a region in which the metal particles are arranged at a lower concentration than the first region, or the second region is a region in which the metal particles are not arranged. A substrate having a plurality of photoelectric conversion elements arranged on a main surface side thereof;
a scintillator disposed on the main surface side and including a plurality of columnar crystals for converting radiation into visible light;
A plate-shaped substrate;
a thermoplastic resin material that covers tip sides of adjacent columnar crystals among the plurality of columnar crystals to position metal particles in a first region between the adjacent columnar crystals, and that is positioned in a second region between the scintillator and the base material to bond the scintillator to the base material,
the first region is a region in which the metal particles are arranged,
The second region is a region in which the metal particles are arranged at a lower concentration than the first region, or the second region is a region in which the metal particles are not arranged .

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