JP2019184278A - Radiation detector - Google Patents

Abstract

To provide a radiation detector that is able to cope with a defect correction process of a reflection layer while hindering a resolution decrease caused by the reflection layer.SOLUTION: A radiation detector 10 comprises an array substrate 11, a scintillator layer 12, a reflection layer 13 and a moisture-proof body 14. The array substrate 11 has a photoelectric conversion element 24. The scintillator layer 12 is formed on the photoelectric conversion element 24 of the array substrate 11. The reflection layer 13 is in the form of a sheet, is disposed on the scintillator 12, and reflects fluorescence from the scintillator 12. In the moisture-proof layer 14, the reflection layer 13 is fixed and covers the scintillator 12 and the reflection layer 13 between the array substrate 11 and itself.SELECTED DRAWING: Figure 1

Description

  Embodiments described herein relate generally to a radiation detector including a reflective layer on a scintillator layer.

  As an X-ray diagnostic detector, a planar X-ray detector using an active matrix has been developed. By detecting the irradiated X-rays with this X-ray detector, an X-ray image or a real-time X-ray image is output as a digital signal. In this X-ray detector, X-rays are converted into visible light, that is, fluorescence by a scintillator layer, and this fluorescence is signaled by an amorphous silicon (a-Si) photodiode or a photoelectric conversion element such as a CCD (Charge Coupled Device). Images are acquired by converting them into electric charges.

The scintillator layer is generally made of cesium iodide (CsI): sodium (Na), cesium iodide (CsI): thallium (Tl), sodium iodide (NaI), or gadolinium oxysulfide (Gd ₂ O _2). S) or the like is used, and the resolution characteristics can be improved by forming grooves by dicing or the like, or by depositing by a vapor deposition method so that a columnar structure is formed.

  There is a method of forming a reflective layer on the scintillator layer in order to improve the use efficiency of fluorescence from the scintillator and improve the sensitivity characteristic. That is, of the fluorescence converted by the scintillator layer, the fluorescence going to the opposite side with respect to the photoelectric conversion element side is reflected by the reflection layer, and the fluorescence reaching the photoelectric conversion element side is increased.

Examples of the reflective layer include a method in which a metal having a high fluorescence reflectance such as a silver alloy or aluminum is formed on the scintillator layer, or a diffuse reflective layer composed of a light scattering material such as TiO ₂ and a binder resin. In general, a method of coating and forming on the scintillator layer is known. Further, there is a method in which a panel in which a scintillator layer is formed on a metal reflective substrate such as an Al substrate is bonded to an array substrate having photoelectric conversion elements with an adhesive or the like. Further, there is a method in which a metal reflector is used and the reflector and the scintillator layer are brought into surface contact without being fixed.

  However, in a method in which a metal having a high fluorescence reflectance is formed on the scintillator layer or a method in which a diffuse reflection reflective layer is applied and formed on the scintillator layer, the reflective layer penetrates between the scintillator layer pillars. A reduction in resolution may be caused by, for example, reducing a light guide effect due to separation between columns of layers.

  In addition, in a method in which a panel having a scintillator layer formed on a metal reflective substrate is bonded to an array substrate having a photoelectric conversion element with an adhesive or the like, the difference in thermal expansion coefficient between the array substrate and the metal reflective substrate As a result, the array substrate is warped.

  Furthermore, in the method in which the reflector and the scintillator layer are in surface contact with each other without being fixed, the reflector does not enter between the pillars of the scintillator layer, the resolution can be suppressed, and the array substrate having the photoelectric conversion element is reflected. Even if the thermal expansion coefficient differs from that of the plate, the reflector plate and the scintillator layer can be displaced without being constrained to each other, thereby suppressing the warpage of the array substrate. However, if there is a defect in a part of the reflector, the acquired image data is corrected. However, if the relative position of the reflector and the scintillator layer changes, the defect moves from the correction position. Correction processing cannot be performed.

Japanese Patent No. 5305996

  The problem to be solved by the present invention is to provide a radiation detector that can cope with defect correction processing of a reflective layer while suppressing a decrease in resolution due to the reflective layer.

  The radiation detector of this embodiment includes a substrate, a scintillator layer, a reflective layer, and a moisture barrier. The substrate has a photoelectric conversion element. The scintillator layer is formed on the photoelectric conversion element of the substrate. The reflection layer is in the form of a sheet, is disposed on the scintillator layer, and reflects fluorescence from the scintillator layer. The moisture-proof body has a reflective layer fixed thereto and covers the scintillator layer and the reflective layer with the substrate.

It is sectional drawing which has made the reflection layer closely_contact | adhere to the scintillator layer in the state which the moistureproof body of the radiation detector which shows one Embodiment displaced by the internal / external differential pressure. It is sectional drawing of the state before the moisture-proof body of a radiation detector same as the above is displaced. It is a model perspective view of a radiation detector same as the above. It is sectional drawing of the moisture-proof body of a radiation detector same as the above.

  Hereinafter, an embodiment will be described with reference to the drawings.

  As shown in FIGS. 1 to 3, the radiation detector 10 is an X-ray image detector (X-ray planar sensor) that detects an X-ray image that is a radiation image, and is used for general medical applications, for example.

  The radiation detector 10 includes an array substrate 11 that is a substrate (photoelectric conversion substrate) having a light source conversion element that converts fluorescence into an electrical signal, and incident X-rays provided on a surface that is one main surface of the array substrate 11. A scintillator layer 12 that converts to fluorescence, a reflective layer 13 that is disposed on the scintillator layer 12 and reflects the fluorescence from the scintillator layer 12 toward the array substrate 11, and the scintillator layer 12 and the reflective layer 13 between the array substrate 11 A moisture-proof body 14 to be covered, a joined body 15 that adheres and seals the periphery of the moisture-proof body 14 to the array substrate 11, and a fixed body 16 that fixes the reflective layer 13 to the moisture-proof body 14 are provided.

  The array substrate 11 converts fluorescence converted from X-rays into, for example, visible light by the scintillator layer 12 into electric signals. The array substrate 11 includes an insulating substrate 20 made of, for example, a glass material, a plurality of pixels 21 formed in a matrix on the insulating substrate 20, and a plurality of control lines (or gate lines) 22 arranged along the row direction. And a plurality of signal lines (or signal lines) 23 arranged along the column direction.

  In each pixel 21, a photoelectric conversion element (photodiode) 24 is provided. These photoelectric conversion elements 24 are disposed below the scintillator layer 12. Furthermore, each pixel 21 includes a thin film transistor (TFT) 25 as a switching element electrically connected to the photoelectric conversion element 24, and a storage capacitor (not shown) as a charge storage unit for storing a signal converted by the photoelectric conversion element 24. )). However, the storage capacitor may double as the capacity of the photoelectric conversion element (photodiode) 24, and is not necessarily required.

  The thin film transistor 25 has a switching function for accumulating and discharging charges generated by the incidence of fluorescence on the photoelectric conversion element 24. The thin film transistor 25 is at least partially made of a semiconductor material such as a-Si as an amorphous semiconductor or polysilicon (P-Si) as a polycrystalline semiconductor.

  A protective layer 26 is formed on the array substrate 11 to cover and protect the pixels 21, control lines 22, signal lines 23, and the like. The protective layer 26 is a silicon nitride based inorganic film, for example. Alternatively, from the viewpoint of adhesion to the scintillator layer 12, the protective layer 26 may be formed by accumulating an organic resin on the inorganic film in a region where the scintillator layer 12 of the array substrate 11 is provided. Examples of the organic resin include acrylic, polyethylene, polypropylene, butyral and other thermoplastic resins. Most preferred is an acrylic resin.

  The control line 22 is disposed between the pixels 21 along the row direction, and is electrically connected to the gate electrode of the thin film transistor 25 of each pixel 21 in the same row.

  The signal line 23 is disposed between the pixels 21 along the column direction, and is electrically connected to the source electrode of the thin film transistor 25 of each pixel 21 in the same column.

  Such a radiation detector 10 is placed on a support body 27 that can absorb X-rays, such as a lead plate, and is electrically connected to a circuit board 28 that is disposed on the back side of the radiation detector 10 with the support body 27 interposed therebetween. Connected. Here, the circuit board 28 is generally equipped with a control circuit having low radiation resistance, an amplification / conversion circuit, and the like. A plurality of wiring pads 29 arranged in the peripheral area of the array substrate 11 are electrically connected to the circuit substrate 28 by a flexible printed circuit board 30 through, for example, an ACF (not shown). Here, the flexible printed circuit board 30 is connected to the respective control lines 22 and signal lines 23. The radiation detector 10 is driven and controlled by the control circuit of the circuit board 28. For example, the control circuit controls the operation state of each thin film transistor 25 through each control line 22, that is, on / off. In addition, the amplification / conversion circuit of the circuit board 28 includes a plurality of charge amplifiers respectively disposed corresponding to the signal lines 23, and a parallel / serial converter in which these charge amplifiers are electrically connected. An analog-digital converter or the like to which a serial converter is electrically connected is included. The analog-digital converter is connected to an image transfer unit 31 that transfers an image.

  The scintillator layer 12 converts incident X-rays into fluorescence, and is provided so as to cover the area where the pixels 21 are located on the array substrate 11. The scintillator layer 12 has a columnar structure formed by, for example, vacuum deposition using cesium iodide (CsI): thallium (Tl), sodium iodide (NaI): thallium (Tl), or cesium bromide (CsBr): europium (Eu). There is something to form. A space exists between these pillars (pillars), and gas can be transferred between the array substrate 11 and the space outside the scintillator layer 12 surrounded by the moisture-proof body 14. In other words, if the internal pressure of the space outside the scintillator layer 12 increases, the gas in that portion escapes to the space between the columns of the scintillator layer 12, and the increase of the internal pressure is suppressed. As the structure, for example, a CsI: Tl vapor deposition film is used for the scintillator layer 12, the film thickness is about 600 μm, and the CsI: Tl pillar thickness is about 3 to 8 μm on the outermost surface. As a result of the indirect but columnar crystal formation, a depletion portion, which is the gap between the columns, is also formed. The ratio of the portion occupied by the phosphor obtained by subtracting the ratio of the depletion portion from the whole is called the filling density, and it depends on the process conditions of the vacuum deposition method for forming the scintillator layer 12.

  The reflective layer 13 reflects the fluorescent light traveling from the scintillator layer 12 toward the opposite side with respect to the array substrate 11 to increase the amount of fluorescent light reaching the photoelectric conversion element 24. The reflection layer 13 has a sheet shape and is disposed between the scintillator layer 12 and the moisture-proof body 14. The sheet-like reflection layer 13 is preferably a single layer that can be a sheet, and is generally inexpensive and can be replaced when a defect occurs.

  Examples of the material for the sheet-like reflective layer 13 include a metal-based material and a resin-based material. Examples of the metal material include an Al reflective film, a silver alloy reflective film + MgO protective film. Examples of the resin-based reflective film include foamed polyethylene terephthalate and those obtained by dispersing titanium oxide in a polyester-based resin.

In the present embodiment, the reflective layer 13 uses a resinous reflective sheet structure in which TiO ₂ is dispersed in a polyester resin from the viewpoint of increasing sensitivity and stability. This resinous reflection sheet generally exists as a commercial product. For example, a TiO ₂ dispersed PET reflection sheet having a thickness of 0.19 mm is used.

  The reflective layer 13 is preferably disposed so as to be pressed against the surface of the scintillator layer 12. This is because if there is a gap between the scintillator layer 12 and the reflective layer 13, the fluorescence from the scintillator layer 12 is scattered in the gap and the resolution of the image output from the radiation detector 10 decreases.

  Further, the moisture-proof body 14 surrounds the scintillator layer 12 with an enclosing net formed together with the array substrate 11 and the joined body 15, and prevents water vapor from entering the internal space 33 in which the scintillator layer 12 is stored. At the same time, the moisture-proof body 14 functions as an X-ray entrance window of the radiation detector 10 and transmits X-rays. Therefore, a light element as thin as possible and a structure free of pinholes is desired, and it is preferable to produce a structure that is shaped into a structure that wraps the Al foil. For example, the moisture-proof body 14 is a commonly available Al foil having a thickness of 0.1 mm. In this case, the moisture-proof body 14 has a low shape retention capability and is easily deformed by an external pressure.

  The moisture-proof body 14 includes a cover portion 34 facing the scintillator layer 12, a side surface portion 35 having a depth including the scintillator layer 12 from a peripheral portion of the cover portion 34, and a flange projecting outward from the side surface portion 35. A portion 36 is provided.

  As shown in FIG. 4, the adhesive width A, which is the width of the flange portion 36 bonded to the array substrate 11 by the bonded body 15 of the moisture-proof body 14, is preferably set to a narrowness near the limit where moisture resistance performance can be secured. . For example, it can be set to about 1 to 10 mm according to the moisture resistance of the joined body 15. The larger the adhesion width A is, the longer the path through which the water vapor of the joined body 15 is dropped, so that the moisture resistance of the moisture-proof body 14 is improved, but at the same time, between the pixel 21 of the radiation detector 10 and the end of the array substrate 11. There is a demerit that the array substrate 11 must be enlarged.

  The drawing depth B of the side surface portion 35 of the moisture-proof body 14 is the sum of the thickness of the scintillator layer 12 and the thickness of the reflective layer 13, whereby deformation of the moisture-proof body 14 after sealing can be minimized. . However, in order to allow a variation in the thickness of the scintillator layer 12, it is preferable to narrow the scintillator layer 12 to about 0.1 mm deep, for example.

  The thinner the thickness C of the moisture-proof body 14, the less X-ray absorption by the moisture-proof body 14 is preferable. However, since the incidence of pinholes is increased, about 0.1 mm is preferable.

  The bonded body 15 is for bonding and sealing the peripheral portion of the moisture-proof body 14 covering the scintillator layer 12 and the reflective layer 13 to the array substrate 11. The joined body 15 is formed by applying an adhesive containing an additive to the interface between the array substrate 11 and the periphery of the moisture-proof body 14 using a dispenser or the like. As the bonded body 15, it is preferable to use an epoxy-based cationic polymerization type adhesive. Moreover, it is preferable to use the filler of the inorganic material which suppresses the moisture permeability of an adhesive agent as an additive.

  The fixed body 16 is located at a position off the photoelectric conversion element 24 of the array substrate 11, and fixes the peripheral portion of the sheet-like reflective layer 13 to the inside of the moisture-proof body 14. The fixed body 16 may be fixed to the moisture-proof body 14 over the entire circumference of the peripheral portion of the reflective layer 13, or may be fixed to the moisture-proof body 14 at portions of the peripheral portion of the reflective layer 13.

  As the fixed body 16, a liquid material that can be applied thinner than a tape-like material having a base material is preferable because attenuation of X-rays can be prevented. The thickness of the fixed body 16 is preferably 50 μm or less in order to prevent X-ray attenuation.

  The fixed body 16 is an adhesive layer using, for example, a commercially available adhesive that can be repeatedly applied. The fixed body 16 adheres and fixes the reflective layer 13 to the moisture-proof body 14, and also maintains the adhesive force even when the reflective layer 13 is peeled off from the reflective layer 13 or the moisture-proof body 14.

  In the manufacturing process of the radiation detector 10, the array substrate 11 on which the scintillator layer 12 is formed and the moistureproof body 14 on which the reflecting layer 13 is fixed with the fixing body 16 are arranged in the vacuum chamber. In a state where the inside of the vacuum chamber is evacuated and reduced to, for example, 0.3 atm or less, the peripheral portion of the moisture-proof body 14 is bonded and sealed to the array substrate 11 with the joined body 15.

  At this time, since the fixed body 16 fixes the sheet-like reflective layer 13 to the inside of the moisture-proof body 14, the reflective layer 13 is prevented from moving when the inside of the vacuum chamber is evacuated. As a result, it is possible to prevent the reflective layer 13 from coming off the pixel 21 and lowering the resolution, and preventing the reflective layer 13 from touching and contaminating the bonded body 15.

  When a UV curable adhesive is used for the bonded body 15, the bonded body 15 is bonded and sealed between the array substrate 11 and the moisture-proof body 14, and then the bonded body 15 is irradiated with ultraviolet rays. Since the ultraviolet rays do not pass through the moisture-proof body 14, they are irradiated from the array substrate 11 side. The irradiation amount is adjusted according to the ultraviolet transmittance of the array substrate 11.

  After the joined body 15 is cured, air is introduced into the vacuum chamber surrounding the entire product. At this time, since the pressure inside the moisture-proof body 14 is lower than the atmospheric pressure outside the moisture-proof body 14, the moisture-proof body 14 has the atmospheric pressure (see the arrow in FIG. 1) and the reflective layer 13 and the atmospheric pressure as shown in FIG. The reflective layer 13 is displaced so as to be pressed against the scintillator layer 12, and the reflective layer 13 is brought into close contact with the scintillator layer 12 (in FIG. 1, the reflective layer 13 is shown as being separated from the scintillator layer 12, but in actuality it is reflective Layer 13 is in intimate contact with scintillator layer 12). And since the volume of the internal space 33 of the moisture-proof body 14 decreases, the internal pressure of the internal space 33 after sealing increases. Further, when the sealing of the moisture-proof body 14 is broken by an Al foil pinhole or the like, since the moisture-proof body 14 is not displaced, it can be confirmed in the process whether or not it is sealed.

  Thereafter, in order to further promote the solidification of the joined body 15, the entire product is left to stand in a furnace of 40 degrees or more. The heating time is adjusted according to the temperature and the adhesive, such as 40 degrees for 10 hours or longer, 80 degrees for 1 hour or longer.

  Through the above steps, a so-called module part of the radiation detector 10 is completed. In this module, the circuit board 28 is electrically connected to the array substrate 11 in a subsequent process, and the module is incorporated into a housing, whereby the radiation detector 10 is completed.

  When the radiation detector 10 is transported, it is assumed that the radiation detector 10 is transported by aircraft. In this case, the radiation detector 10 is exposed to the atmosphere of 0.7 atm. At this time, for example, if the pressure in the internal space 33 of the moisture-proof body 14 is 1 atm, the gas in the internal space 33 of the moisture-proof body 14 is caused by the differential pressure between the pressure outside the moisture-proof body 14 and the pressure inside. , The moisture-proof body 14 swells up, and the array substrate 11 may be destroyed. Therefore, in order to prevent the moisture-proof body 14 from expanding, the pressure in the internal space 33 of the moisture-proof body 14 is preferably maintained at 0.7 atm or less.

  In the radiation detector 10, when the reflective layer 13 is formed on the scintillator layer 12 by film formation or application, the reflective layer 13 penetrates between the pillars of the scintillator layer 12 to reduce the resolution, but the sheet shape By using this reflective layer 13, the reflective layer 13 does not penetrate between the columns of the scintillator layer 12, and the resolution characteristics can be improved.

  Furthermore, when the sheet-like reflective layer 13 is used, the reflective layer 13 may move. However, since the reflective layer 13 is fixed to the moisture-proof body 14 by the fixed body 16, the reflective layer 13 moves. Can be regulated. Therefore, when evacuating the inside of the vacuum chamber in the manufacturing process, it is possible to prevent the reflection layer 13 from being removed from the pixel 21 and reducing the resolution, and preventing the reflection layer 13 from touching and contaminating the bonded body 15. it can.

  Further, when there is a defect due to a black spot or unevenness in a part of the reflective layer 13, the defect correction process is performed with the position of the defect in the acquired image data as the correction position. In this case, if the sheet-like reflective layer 13 is not fixed to the moisture-proof body 14, the position of the defect in the reflective layer 13 moves from the correction position, and the defect correction processing cannot be performed normally. By fixing the reflective layer 13 to the moisture-proof body 14, the defect position of the reflective layer 13 does not move from the correction position, and defect correction processing can be performed.

  In addition, the fixed body 16 can be prevented from being affected by the acquired image when the X-rays are incident because the fixed body 16 is located at a position off the photoelectric conversion element 24.

  Furthermore, since the fixed body 16 has a uniform thickness of 50 μm or less, it is possible to prevent the acquired image from being affected when X-rays are incident.

  Furthermore, the fixed body 16 is an adhesive layer that adheres and fixes the reflective layer 13 to the moisture-proof body 14, and it is preferable that the adhesive strength is maintained even when the reflective layer 13 or the moisture-proof body 14 is peeled off. That is, it is preferable that the adhesive strength of the adhesive layer is weak to some extent, and the adhesive strength of the adhesive layer is maintained even after the reflective layer 13 is peeled from the moisture-proof body 14. In this way, the adhesive layer is weak to some extent, so that the reflective layer 13 is not properly positioned on the moisture-proof body 14 so that the reflective layer 13 is reapplied, or the reflective layer 13 is defective and replaced. In this case, it is possible to peel off the reflective layer 13 without damaging the reflective layer 13 and the moisture-proof body 14. In addition, since the adhesive layer can be reused because the adhesive force is maintained even after the reflective layer 13 is peeled from the moisture-proof body 14, it is not necessary to remove the adhesive layer, and the reflective layer 13 at the time of removing the adhesive layer is removed. In addition, the deformation and alteration of the moisture-proof body 14 can be prevented, and the number of steps for forming the adhesive layer can be reduced again.

  Further, the moisture-proof body 14 has a lower inner pressure than the outer atmospheric pressure, and is displaced so as to be pressed against the reflective layer 13 and the scintillator layer 12 due to a differential pressure between the outer atmospheric pressure and the inner pressure. Is in close contact with the scintillator layer 12. Therefore, light scattering between the scintillator layer 12 and the reflective layer 13 is suppressed, and the resolution characteristics of the radiation detector 10 can be improved.

  As described above, when the reflection layer 13 is pressed against the scintillator layer 12 by the moisture-proof body 14 displaced by the differential pressure between the outer atmospheric pressure and the inner pressure, an improvement in resolution is expected compared to the state where the reflection layer 13 is not pressed. . Then, in order to confirm the improvement in resolution by pressing the reflective layer 13 against the scintillator layer 12, a sample was prepared under the following conditions, and a comparative evaluation was performed.

  Sample 1: A sheet-like reflective layer 13 was disposed on a CsI scintillator layer 12, and a moisture-proof body 14 was provided without evacuating the inside.

  Sample 2: A sheet-like reflective layer 13 was placed on a CsI scintillator layer 12, and the inside was evacuated to provide a moisture-proof body 14.

In both sample 1 and sample 2, a columnar structure crystal CsI having a thickness of 600 μm was used for the scintillator layer 12, and a sheet having a thickness of 0.19 mm in which TiO ₂ was dispersed in PET resin was used for the reflective layer 13.

  In sample 1 and sample 2, the single CTF (Contrast Transfer Function) (1) of the scintillator layer 12 and the CTF (2) after formation of the moisture barrier 14 are measured, and (2) / (1) is calculated. The change in resolution was measured.

  In the sample 1, the result was (2) / (1) = 0.593, and in the sample 2, the result was (2) / (1) = 0.790. From this result, it was shown that the resolution is improved by pressing the reflective layer 13 against the scintillator layer 12 by the moisture-proof body 14 displaced by the differential pressure between the outside atmospheric pressure and the inside pressure.

  Further, since the reflection layer 13 is pressed against the scintillator layer 12 by the moisture-proof body 14 displaced by the differential pressure between the outside atmospheric pressure and the inside pressure, the movement of the reflection layer 13 can be restricted. Therefore, even if there is a defect due to black spots or unevenness in a part of the reflective layer 13, the defect position of the reflective layer 13 does not move from the correction position, and defect correction processing can be performed.

  And, by pressing the reflective layer 13 against the scintillator layer 12 by the moisture-proof body 14 displaced by the differential pressure between the outer atmospheric pressure and the inner pressure, the reflective layer 13 does not move relative to the scintillator layer 12, that is, It was confirmed that the position of the defect in the reflective layer 13 did not move.

  As a confirmation method, a module of the radiation detector 10 as shown in FIG. 1 is prepared using a reflective layer 13 with an X mark using an oil-based pen, and temperatures of 60 ° C. and −20 ° C. are applied to this module. The cycle was repeated 30 times, and the method of confirming the coordinate change of the X mark was taken. As a result, no change in the coordinates of the X mark could be confirmed.

  By pressing the sheet-like reflective layer 13 against the scintillator layer 12 by the moisture-proof body 14 displaced by the differential pressure between the outer atmospheric pressure and the inner pressure, the reflective layer 13 does not move relative to the scintillator layer 12, That is, it was shown that the position of the defect in the reflective layer 13 does not move.

  Then, the sheet-like reflective layer 13 is fixed to the moisture-proof body 14 by the fixed body 16, and the sheet-like reflective layer 13 is scintillated by the moisture-proof body 14 displaced by the differential pressure between the outer atmospheric pressure and the inner pressure. Due to the synergistic effect of pressing against the layer 12, the reflective layer 13 does not move relative to the scintillator layer 12, and even if there is a defect due to black spots or unevenness in a part of the reflective layer 13, the defect of the reflective layer 13 The position does not move from the correction position, and defect correction processing can be performed.

  The fixing body 16 is not limited to the adhesive layer, and may be an adhesive layer or a mechanical fixing means.

  The reflective layer 13 may be a reflective surface formed on the inner surface of the moisture-proof body 14 without using the fixed body 16.

  Although several embodiments of the present invention have been described, these embodiments are presented by way of example and are not intended to limit the scope of the invention. These novel embodiments can be implemented in various other forms, and various omissions, replacements, and changes can be made without departing from the scope of the invention. These embodiments and modifications thereof are included in the scope and gist of the invention, and are included in the invention described in the claims and the equivalents thereof.

10 Radiation detector
11 Array substrate
12 Scintillator layer
13 Reflective layer
14 Moisture-proof body
16 Fixed body
24 photoelectric conversion element

Claims (6)

A substrate having a photoelectric conversion element;
A scintillator layer formed on the photoelectric conversion element of the substrate;
A sheet-like reflective layer that is disposed on the scintillator layer and reflects fluorescence from the scintillator layer;
A radiation detector comprising: the reflective layer fixed; and a moisture barrier covering the scintillator layer and the reflective layer between the substrate and the substrate. The radiation detector according to claim 1, further comprising: a fixed body that fixes the reflective layer to the moisture-proof body. The radiation detector according to claim 2, wherein the fixed body is at a position off the photoelectric conversion element of the substrate. The radiation detector according to claim 2 or 3, wherein the fixed body has a thickness of 50 µm or less. The fixed body is an adhesive layer that sticks and fixes the reflective layer to the moisture-proof body, and maintains the adhesive force even in a state where the reflective layer is peeled off from the reflective layer or the moisture-proof body. One radiation detector. The moisture-proof body is characterized in that the inner pressure is lower than the outer atmospheric pressure, and the reflective layer is closely attached to the scintillator layer in a state of being displaced by a differential pressure between the outer atmospheric pressure and the inner pressure. The radiation detector according to any one of claims 1 to 5.

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