Scintillator unit and method for manufacturing scintillator unit

Abstract

This scintillator unit comprises: a support; a scintillator layer disposed on the support and including a plurality of columnar crystals; an optical functional layer disposed on an effective portion of the scintillator layer; and a moisture-proof layer integrally covering both the scintillator layer and the optical functional layer. The moisture-proof layer is in contact with the plurality of columnar crystals at an outer edge of the scintillator layer and enters gaps of the plurality of columnar crystals.

Description

Scintillator unit and method for manufacturing scintillator unit

[0001] The present disclosure relates to a scintillator unit and a method for manufacturing a scintillator unit.

[0002] As a conventional scintillator unit, Patent Document 1 describes a radiation detection module including an array substrate having a plurality of photoelectric conversion sections, a scintillator layer disposed on the array substrate, a reflective layer disposed on the scintillator layer, a frame-shaped sealing section joined to the outer edge of the scintillator layer on the array substrate, and a moisture-proof layer covering the scintillator layer, the reflective layer, and the sealing section on the array substrate, wherein the scintillator layer contains a plurality of columnar crystals.

[0003] Japanese Patent Application Laid-Open No. 2020-79787

[0004] When the scintillator layer contains multiple columnar crystals, as in the radiation detection module described in Patent Document 1, it is expected that the light emitted in the scintillator layer in response to incident radiation will be propagated to the array substrate with high output and high resolution, but it is also important to ensure that the scintillator layer is moisture-proof.

[0005] In the radiation detection module described in Patent Document 1, the interface between the array substrate and the edge of the moisture-proof layer is separated from the scintillator layer by the amount of the frame-shaped sealing portion, but there is a risk that the edge of the moisture-proof layer will peel off from the array substrate, and moisture will enter through the gap formed between the array substrate and the edge of the moisture-proof layer and reach the scintillator layer.

[0006] The present disclosure aims to provide a scintillator unit that can propagate light emitted in a scintillator layer in response to incident radiation with high output and high resolution, while ensuring moisture resistance of the scintillator layer, and a method for manufacturing the scintillator unit.

[0007] A scintillator unit according to one aspect of the present disclosure is [1] "a scintillator unit comprising a support, a scintillator layer disposed on the support and including a plurality of columnar crystals, an optical functional layer disposed on an effective portion of the scintillator layer, and a moisture-proof layer integrally covering the scintillator layer and the optical functional layer, wherein the moisture-proof layer is in contact with the plurality of columnar crystals at the outer edge of the scintillator layer and penetrates into gaps between the plurality of columnar crystals."

[0008] In the scintillator unit, the scintillator layer and the optical function layer are integrally covered with a moisture-proof layer, with the optical function layer disposed on the effective portion of the scintillator layer containing a plurality of columnar crystals. This prevents the moisture-proof layer from penetrating into gaps between the plurality of columnar crystals from the side opposite the support during manufacturing of the scintillator unit. Therefore, in the effective portion of the scintillator layer, the refractive index difference between each columnar crystal and the gap region is large, making it difficult for light emitted from each columnar crystal to exit the columnar crystals. Furthermore, at the outer edge of the scintillator layer, the moisture-proof layer that integrally covers the scintillator layer and the optical function layer is in contact with the plurality of columnar crystals and penetrates into the gaps between the plurality of columnar crystals. This prevents the moisture-proof layer from peeling off from the outer edge of the scintillator layer and also prevents moisture from reaching the effective portion of the scintillator layer. Therefore, with the scintillator unit, light emitted from the scintillator layer in response to incident radiation can be propagated with high power and high resolution, and moisture resistance of the scintillator layer can be ensured.

[0009] A scintillator unit according to one aspect of the present disclosure may be [2] "the scintillator unit according to the above [1], in which the thickness of the scintillator layer at the outer edge portion becomes smaller toward the outside." According to this scintillator unit, during manufacturing of the scintillator unit, the moisture-proof layer can easily enter the gaps between the plurality of columnar crystals at the outer edge portion of the scintillator layer from the side opposite to the support, thereby more reliably ensuring the moisture-proof property of the scintillator layer.

[0010] A scintillator unit according to one aspect of the present disclosure may be [3] "the scintillator unit according to [1] or [2] above, in which the optical function layer is in contact with the effective portion of the scintillator layer." This scintillator unit can simplify the structure and achieve a configuration in which a moisture-proof layer does not intrude into gaps between a plurality of columnar crystals from the side opposite the support in the effective portion of the scintillator layer.

[0011] A scintillator unit according to one aspect of the present disclosure may be [4] "the scintillator unit according to the above [1] or [2], further comprising an adhesive layer disposed between the effective portion of the scintillator layer and the optical functional layer." This scintillator unit can achieve a configuration in which a moisture-proof layer does not intrude into gaps between the plurality of columnar crystals in the effective portion of the scintillator layer from the side opposite the support, while stabilizing support for the optical functional layer.

[0012] A scintillator unit according to one aspect of the present disclosure may be [5] "the scintillator unit according to any one of the above [1] to [4], wherein the optical functional layer is a reflective layer that reflects light emitted from the scintillator layer in response to incident radiation." With this scintillator unit, light that travels in the opposite direction from the support in each columnar crystal is reflected by the reflective layer, allowing the light emitted from the scintillator layer to propagate with higher output.

[0013] A scintillator unit according to one aspect of the present disclosure may be [6] "the scintillator unit according to any one of the above [1] to [4], wherein the optical functional layer is an absorption layer that absorbs light emitted from the scintillator layer in response to incidence of radiation." According to this scintillator unit, light that travels in the opposite direction from the support in each columnar crystal is absorbed by the absorption layer, thereby making it possible to suppress the generation of stray light due to scattering of light that travels in the opposite direction from the support, and to propagate the light emitted from the scintillator layer with higher resolution.

[0014] A scintillator unit according to one aspect of the present disclosure may be [7] "the scintillator unit according to any one of the above [1] to [6], wherein the support is a fiber optic plate." With this scintillator unit, light propagated from the scintillator layer with high output and high resolution can be propagated to, for example, a sensor panel while maintaining the output and resolution.

[0015] A scintillator unit according to one aspect of the present disclosure may be [8] "the scintillator unit according to the above [7], further including a sensor panel arranged on the opposite side of the scintillator layer with respect to the fiber optic plate." With this scintillator unit, light propagated from the scintillator layer with high output and high resolution can be propagated to the sensor panel while maintaining the output and resolution.

[0016] A scintillator unit according to one aspect of the present disclosure may be [9] "the scintillator unit according to any one of the above [1] to [6], wherein the support is a sensor panel." With this scintillator unit, light propagated from the scintillator layer with high output and high resolution can be propagated directly to the sensor panel.

[0017] One aspect of the present disclosure relates to a method for manufacturing a scintillator unit, which is

[10] "a method for manufacturing a scintillator unit, comprising the steps of: forming a scintillator layer including a plurality of columnar crystals on a support; arranging an optical functional layer on an effective portion of the scintillator layer; and, in a state in which the optical functional layer is arranged on the effective portion of the scintillator layer and the outer edge portion of the scintillator layer is exposed, forming a moisture-proof layer by vapor deposition that integrally covers the scintillator layer and the optical functional layer."

[0018] In the method for manufacturing the scintillator unit, an optical functional layer is disposed on the effective portion of the scintillator layer, and the outer edge of the scintillator layer is exposed. A moisture-proof layer is then formed by vapor deposition to integrally cover the scintillator layer and the optical functional layer. This prevents the moisture-proof layer from penetrating into gaps between the columnar crystals from the opposite side of the support in the effective portion of the scintillator layer. Therefore, in the manufactured scintillator unit, the refractive index difference between each columnar crystal and the gap region is large in the effective portion of the scintillator layer, making it difficult for light emitted from each columnar crystal to exit the columnar crystals. Furthermore, at the outer edge of the scintillator layer, the moisture-proof layer contacts the columnar crystals and penetrates into the gaps between the columnar crystals. Therefore, in the manufactured scintillator unit, the moisture-proof layer is less likely to peel off from the outer edge of the scintillator layer, and moisture is less likely to reach the effective portion of the scintillator layer. Therefore, according to the above-mentioned method for manufacturing a scintillator unit, it is possible to obtain a scintillator unit that can propagate light emitted in the scintillator layer in response to incident radiation with high output and high resolution, while also ensuring the moisture resistance of the scintillator layer.

[0019] According to the present disclosure, it is possible to provide a scintillator unit and a method for manufacturing a scintillator unit that can propagate light emitted in a scintillator layer in response to incident radiation with high output and high resolution, while ensuring moisture resistance of the scintillator layer.

[0020] FIG. 1 is a cross-sectional view of an example scintillator unit. FIG. 2 is a cross-sectional view of a portion of a scintillator unit of an example and a comparative example. FIG. 3 is a graph showing the characteristics of the scintillator units of an example and a comparative example. FIG. 4 is a cross-sectional view showing a manufacturing process of the scintillator unit shown in FIG. 1. FIG. 5 is a cross-sectional view showing a manufacturing process of the scintillator unit shown in FIG. 1. FIG. 6 is a cross-sectional view showing a manufacturing process of the scintillator unit shown in FIG. 1. FIG. 7 is a cross-sectional view of a modified scintillator unit. FIG. 8 is a cross-sectional view of a modified scintillator unit. FIG. 9 is a cross-sectional view of a modified scintillator unit. FIG. 10 is a side view of a modified fiber optic plate. FIG. 11 is a cross-sectional view of a modified scintillator unit.

[0021] Hereinafter, an example of the present disclosure will be described in detail with reference to the drawings. In each drawing, the same or corresponding parts are denoted by the same reference numerals, and duplicated explanations will be omitted. [Configuration of scintillator unit]

[0022] 1 , the scintillator unit 1 includes a fiber optic plate (support) 2, a scintillator layer 3 disposed on the fiber optic plate 2, a reflective layer (optical functional layer) 4 disposed on the scintillator layer 3, and a first organic layer (moisture-proof layer) 5, an inorganic layer 6, and a second organic layer 7, which cover the scintillator layer 3 and the reflective layer 4. The scintillator unit 1 is disposed on a sensor panel to form a radiation detector. In this radiation detector, when radiation (e.g., X-rays) is incident on the scintillator layer 3, light is emitted from the scintillator layer 3, and the light is propagated by the fiber optic plate 2 to the sensor panel where it is detected. Such a radiation detector is used as a radiation imaging device, for example, in a medical radiation image diagnostic device, a non-destructive testing device, etc.

[0023] The fiber optic plate 2 has a light incident surface 2a, a light exit surface 2b, and a side surface 2c. The light incident surface 2a and the light exit surface 2b face each other in direction A, which is the thickness direction of the fiber optic plate 2. The fiber optic plate 2 is composed of a bundle of multiple optical fibers 21. Each optical fiber 21 extends in direction A between the light incident surface 2a and the light exit surface 2b. Each optical fiber 21 propagates light emitted from the scintillator layer 3 in response to incident radiation from the light incident surface 2a to the light exit surface 2b.

[0024] The scintillator layer 3 is formed on the light incident surface 2 a of the fiber optic plate 2. The scintillator layer 3 includes a plurality of columnar crystals 30. The plurality of columnar crystals 30 are aligned along the light incident surface 2 a. Each columnar crystal 30 extends in direction A. An end 30 a of each columnar crystal 30 opposite the fiber optic plate 2 tapers toward the side opposite the fiber optic plate 2. The material of the scintillator layer 3 (i.e., the material of each columnar crystal 30) is, for example, an alkali halide crystal such as CsI:Tl (cesium iodide containing thallium as an activator), CsI:Na (cesium iodide containing sodium as an activator), CsI:Ce (cesium iodide containing cerium as an activator), or CsI:Tl,Eu (cesium iodide containing thallium and europium as activators).

[0025] The scintillator layer 3 has an effective portion 31 and an outer edge portion 32. The outer edge portion 32 is a portion extending in a frame shape along the outer edge of the scintillator layer 3 when viewed from direction A. The outer edge portion 32 is located inside the light incident surface 2a when viewed from direction A. The effective portion 31 is a portion surrounded by the outer edge portion 32 when viewed from direction A. The lengths of the columnar crystals 30 in the effective portion 31 are approximately equal. That is, the thickness of the scintillator layer 3 in the effective portion 31 is approximately constant. The thickness of the scintillator layer 3 in the effective portion 31 is approximately 50 to 1000 μm (e.g., 600 μm). The length of each columnar crystal 30 in the outer edge portion 32 becomes shorter toward the outside. That is, the thickness of the scintillator layer 3 in the outer edge portion 32 becomes smaller toward the outside, and the width of the scintillator layer 3 in the outer edge portion 32 (the width in the direction perpendicular to direction A) becomes smaller with increasing distance from the fiber optic plate 2. In other words, the outer edge 32 of the scintillator layer 3 forms a slope. The width of the scintillator layer 3 at the outer edge 32 is about 100 to 2000 μm (for example, 500 μm).

[0026] The reflective layer 4 is disposed on the effective portion 31 of the scintillator layer 3 and is in contact with the effective portion 31 of the scintillator layer 3. The reflective layer 4 reflects light emitted from the scintillator layer 3 in response to incident radiation. Because the reflective layer 4 is disposed on the effective portion 31, it reflects light traveling in the direction opposite the fiber optic plate 2 in each of the columnar crystals 30 constituting the effective portion 31 toward the fiber optic plate 2. The reflective layer 4 is, for example, a resin layer containing a light-reflective pigment, such as a white film (white polyurethane containing light-scattering particles) with a hot-melt resin. The end portions 30a of each of the columnar crystals 30 constituting the effective portion 31 may be embedded in the portion of the reflective layer 4 facing the fiber optic plate 2 (for example, the portion made of hot-melt resin). The thickness of the reflective layer 4 is approximately 10 to 250 μm (for example, 55 μm).

[0027] The first organic layer 5 integrally covers the scintillator layer 3 and the reflective layer 4. The first organic layer 5 integrally covers the surface of the reflective layer 4 opposite the scintillator layer 3, the outer edge 32 of the scintillator layer 3, the outer edge region of the light incident surface 2a of the fiber optic plate 2, and the side surface 2c of the fiber optic plate 2. The material of the first organic layer 5 is, for example, parylene (polyparaxylene). The thickness of the first organic layer 5 is approximately 0.5 to 40 μm (e.g., 10 μm). The inorganic layer 6 integrally covers the outer surface of the first organic layer 5. The material of the inorganic layer 6 is, for example, aluminum. The thickness of the inorganic layer 6 is approximately 100 to 5000 Å (e.g., 2500 Å). The second organic layer 7 integrally covers the outer surface of the inorganic layer 6. The material of the second organic layer 7 is, for example, parylene. The thickness of the second organic layer 7 is about 0.5 to 40 μm (for example, 10 μm).

[0028] The first organic layer 5 is in contact with the plurality of columnar crystals 30 at the outer edge portion 32 of the scintillator layer 3 and fills the gaps S between the plurality of columnar crystals 30. Here, the gaps S between the plurality of columnar crystals 30 are spaces sandwiched between the ends 30a and the columnar portions 30b of adjacent columnar crystals 30. The columnar portions 30b are portions of the columnar crystals 30 excluding the ends 30a that taper toward the side opposite to the fiber optic plate 2, and extend in the direction A (see (b) of FIG. 2). At the outer edge portion 32 of the scintillator layer 3, the gaps S between the plurality of columnar crystals 30 may or may not be completely filled with the first organic layer 5. That is, at the outer edge portion 32 of the scintillator layer 3, it is sufficient that the first organic layer 5 fills at least a portion of the gaps S between the plurality of columnar crystals 30. The first organic layer 5 penetrates into at least a part of the gaps S formed by the columnar portions 30b among the gaps S between the plurality of columnar crystals 30. Furthermore, in a direction perpendicular to the direction A, the first organic layer 5 penetrates into the gaps S between the plurality of columnar crystals 30 by the distance of at least one columnar crystal 30 from the outermost periphery of the outer edge portion 32 of the scintillator layer 3. Note that in the effective portion 31 of the scintillator layer 3, the gaps S between the plurality of columnar crystals 30 form empty spaces.

[0029] As described above, in the scintillator unit 1, the reflective layer 4 is disposed on the effective portion 31 of the scintillator layer 3, which includes a plurality of columnar crystals 30, and the scintillator layer 3 and the reflective layer 4 are integrally covered by the first organic layer 5. This prevents the first organic layer 5 from entering the gaps S between the plurality of columnar crystals 30 in the effective portion 31 of the scintillator layer 3 from the side opposite the fiber optic plate 2 during manufacturing of the scintillator unit 1. Therefore, in the effective portion 31 of the scintillator layer 3, the refractive index difference between each columnar crystal 30 and the region of the gaps S becomes large, making it difficult for light emitted from each columnar crystal 30 to exit the columnar crystal 30. Furthermore, in the outer edge portion 32 of the scintillator layer 3, the first organic layer 5, which integrally covers the scintillator layer 3 and the reflective layer 4, is in contact with the plurality of columnar crystals 30 and enters the gaps S between the plurality of columnar crystals 30. This makes it more difficult for first organic layer 5 to peel off from outer edge portion 32 of scintillator layer 3 than when first organic layer 5 is simply attached only to the outermost surface of scintillator layer 3, and also makes it possible to lengthen the path through which moisture from the outside penetrates, making it more difficult for moisture to reach effective portion 31 of scintillator layer 3. Thus, according to scintillator unit 1, light emitted in scintillator layer 3 in response to incident radiation can be propagated with high output and high resolution, and the moisture resistance of scintillator layer 3 can be ensured.

[0030] In the scintillator unit 1, the thickness of the scintillator layer 3 at the outer edge portion 32 becomes smaller toward the outside. This makes it easier for the first organic layer 5 to enter the gaps S between the plurality of columnar crystals 30 at the outer edge portion 32 of the scintillator layer 3 from the side opposite to the fiber optic plate 2 during manufacturing of the scintillator unit 1, thereby more reliably ensuring the moisture resistance of the scintillator layer 3.

[0031] In the scintillator unit 1, a reflective layer 4 that reflects light emitted from the scintillator layer 3 in response to incident radiation is disposed on the effective portion 31 of the scintillator layer 3. As a result, in each columnar crystal 30, light that travels in the opposite direction to the fiber optic plate 2 is reflected by the reflective layer 4, thereby increasing the light output from each columnar crystal 30.

[0032] In the scintillator unit 1, the reflective layer 4 is in contact with the effective portion 31 of the scintillator layer 3. This simplifies the structure and realizes a configuration in which the first organic layer 5 does not intrude into the gaps S between the plurality of columnar crystals 30 in the effective portion 31 of the scintillator layer 3 from the side opposite to the fiber optic plate 2.

[0033] In the scintillator unit 1, the scintillator layer 3 is disposed on the fiber optic plate 2. This allows light propagated from the scintillator layer 3 with high output and high resolution to be propagated to, for example, a sensor panel while maintaining the output and resolution.

[0034] 2A is a cross-sectional view of a portion of a scintillator unit of a comparative example, and FIG. 2B is a cross-sectional view of a portion of a scintillator unit of an example. As shown in FIG. 2A, when the first organic layer 5 fills the gaps S between the plurality of columnar crystals 30 in the effective portion 31 of the scintillator layer 3, the refractive index difference between each columnar crystal 30 and the gap S region becomes small, and light emitted from each columnar crystal 30 becomes easy to emit outside each columnar crystal 30. On the other hand, as shown in FIG. 2B, when the first organic layer 5 does not fill the gaps S between the plurality of columnar crystals 30 in the effective portion 31 of the scintillator layer 3, the refractive index difference between each columnar crystal 30 and the gap S region becomes large, and light emitted from each columnar crystal 30 becomes hard to emit outside each columnar crystal 30.

[0035] As described above, in the scintillator unit of the comparative example shown in FIG. 2(a), optical crosstalk is likely to occur between adjacent columnar crystals 30, and there is a risk of light absorption by the first organic layer 5 that has entered the gaps S between the multiple columnar crystals 30. On the other hand, in the scintillator unit of the example shown in FIG. 2(b), optical crosstalk is unlikely to occur between adjacent columnar crystals 30. FIG. 3 is a graph showing the characteristics of the scintillator units of the example and the comparative example. As shown in FIG. 3, compared to the scintillator unit of the comparative example, the scintillator unit of the example has an improvement in resolution of about 10% and an improvement in light output of about 30%. [Method of manufacturing a scintillator unit]

[0036] A method for manufacturing the scintillator unit 1 described above will be described. First, as shown in FIG. 4A, a fiber optic plate 2 is prepared. Next, as shown in FIG. 4B, a scintillator layer 3 including a plurality of columnar crystals 30 is formed on the light incident surface 2a of the fiber optic plate 2 (a step of forming a scintillator layer). The scintillator layer 3 is formed by, for example, a vapor deposition method. Next, as shown in FIG. 4C, a mask 11 is formed on the light exit surface 2b of the fiber optic plate 2.

[0037] Next, as shown in (a) of FIG. 5, a reflective layer 4 is disposed on the effective portion 31 of the scintillator layer 3 (a step of disposing a reflective layer). The reflective layer 4 is fixed on the effective portion 31 of the scintillator layer 3, for example, by softening a hot-melt resin attached to a white film. Next, as shown in (b) of FIG. 5, a first organic layer 5 is formed by vapor deposition in a state in which the reflective layer 4 is disposed on the effective portion 31 of the scintillator layer 3 and the outer edge portion 32 of the scintillator layer 3 is exposed (a step of forming a first organic layer). As a result, the fiber optic plate 2, the mask 11, the scintillator layer 3, and the reflective layer 4 are integrally covered with the first organic layer 5. The first organic layer 5 is formed, for example, by a CVD method.

[0038] Next, as shown in (c) of Fig. 5, an inorganic layer 6 is formed so as to integrally cover the outer surface of the first organic layer 5. The inorganic layer 6 is formed, for example, by vapor deposition. Next, as shown in (a) of Fig. 6, a second organic layer 7 is formed so as to integrally cover the outer surface of the inorganic layer 6. The second organic layer 7 is formed, for example, by CVD. Next, as shown in (b) of Fig. 6, the portions of the first organic layer 5, the inorganic layer 6, and the second organic layer 7 that were disposed on the mask 11 are removed together with the mask 11 from the light exit surface 2b of the fiber optic plate 2. This results in the scintillator unit 1 being obtained.

[0039] As described above, in the method for manufacturing the scintillator unit 1, the reflective layer 4 is disposed on the effective portion 31 of the scintillator layer 3, and the outer edge portion 32 of the scintillator layer 3 is exposed. Then, the first organic layer 5 is formed by vapor deposition to integrally cover the scintillator layer 3 and the reflective layer 4. This prevents the first organic layer 5 from entering the gaps S between the plurality of columnar crystals 30 from the side opposite the fiber optic plate 2 in the effective portion 31 of the scintillator layer 3. Therefore, in the manufactured scintillator unit 1, the refractive index difference between each columnar crystal 30 and the gap S in the effective portion 31 of the scintillator layer 3 is large, making it difficult for light emitted from each columnar crystal 30 to exit the columnar crystal 30. Furthermore, in the outer edge portion 32 of the scintillator layer 3, the first organic layer 5 contacts the plurality of columnar crystals 30 and enters the gaps S between the plurality of columnar crystals 30. Therefore, in the manufactured scintillator unit 1, the first organic layer 5 is less likely to peel off from the outer edge portion 32 of the scintillator layer 3, and moisture is less likely to reach the effective portion 31 of the scintillator layer 3. Therefore, according to the manufacturing method of the scintillator unit 1, it is possible to obtain a scintillator unit 1 that can propagate light emitted in the scintillator layer 3 in response to incident radiation with high output and high resolution, and that can ensure the moisture resistance of the scintillator layer 3. [Modification]

[0040] The present disclosure is not limited to the above-described example. For example, as shown in FIG. 7 , an adhesive layer 8 may be disposed between the effective portion 31 of the scintillator layer 3 and the reflective layer 4. This allows for stable support of the reflective layer 4 while realizing a configuration in which the first organic layer 5 does not intrude into the gaps S between the multiple columnar crystals 30 in the effective portion 31 of the scintillator layer 3 from the side opposite the fiber optic plate 2. The adhesive layer 8 is made of an organic material having optical transparency, such as OCA (Optical Clear Adhesive), hot-melt resin, or the like. The thickness of the adhesive layer 8 is approximately 0.5 to 50 μm (e.g., 10 μm).

[0041] 8 , the reflective layer 4 is disposed on the effective portion 31 and the outer edge portion 32 of the scintillator layer 3, and does not have to cover an outward-facing region of the outer edge portion 32 of the scintillator layer 3. In other words, it is sufficient that the reflective layer 4 does not cover at least a portion of the outer edge portion 32 of the scintillator layer 3 (a portion extending in a frame shape along the outer edge of the scintillator layer 3 when viewed from direction A). Then, it is sufficient that the first organic layer 5 is in contact with the plurality of columnar crystals 30 and enters the gaps S between the plurality of columnar crystals 30 in at least a portion of the outer edge portion 32 of the scintillator layer 3.

[0042] 8 , in the scintillator unit 1, an absorption layer 9 that absorbs light emitted from the scintillator layer 3 in response to incident radiation may be disposed on the effective portion 31 of the scintillator layer 3. In this manner, light that travels in the opposite direction from the fiber optic plate 2 in each columnar crystal 30 is absorbed by the absorption layer 9, thereby suppressing the generation of stray light due to scattering of light that travels in the opposite direction from the fiber optic plate 2, and allowing the light emitted from the scintillator layer 3 to propagate with higher resolution. The absorption layer 9 is, for example, a resin layer containing a light-absorbing pigment. In all of the examples described above or below, the absorption layer 9 can be used as the optical functional layer in place of the reflective layer 4.

[0043] As shown in FIG. 9 , in the scintillator unit 1, the scintillator layer 3 may be disposed on a sensor panel 10. In this case, the scintillator unit 1 shown in FIG. 9 constitutes a radiation detector. This allows light propagated from the scintillator layer 3 with high output and high resolution to be directly propagated to the sensor panel 10. In the scintillator unit 1 shown in FIG. 9 , the effective portion 31 of the scintillator layer 3 is disposed on the light-receiving surface 10a of the sensor panel 10, which is provided with a plurality of photoelectric conversion elements. In the scintillator unit 1 shown in FIG. 9 , the edges of the first organic layer 5, the inorganic layer 6, and the second organic layer 7 are covered by a sealing member 12 on the sensor panel 10. Examples of materials for the sealing member 12 include epoxy, silicone, fluorine, urethane, and acrylic. The material for the sealing member 12 may include a filler material made of an inorganic material such as glass. In all of the examples described above and below, a sensor panel 10 can be used as the support instead of the fiber optic plate 2.

[0044] 10(a), the shape of the fiber optic plate 2 may be a truncated cone shape widening toward the light incident surface 2a, or a truncated cone shape widening toward the light exit surface 2b. As shown in Fig. 10(b), the shape of the fiber optic plate 2 may be a stepped shape widening toward the light incident surface 2a, or a stepped shape widening toward the light exit surface 2b. In addition, the scintillator unit 1 does not have to include the inorganic layer 6 and the second organic layer 7.

[0045] As shown in Fig. 11 , the scintillator unit 1 using the fiber optic plate 2 as the support may further include a sensor panel 10 arranged on the opposite side of the scintillator layer 3 with respect to the fiber optic plate 2. In this case, the scintillator unit 1 shown in Fig. 11 constitutes a radiation detector. This allows light propagated from the scintillator layer 3 with high output and high resolution to propagate to the sensor panel 10 while maintaining the output and resolution. In the scintillator unit 1 shown in Fig. 11 , a light-transmitting bonding layer (e.g., a layer made of OCA or a thermosetting resin) may be arranged between the light-emitting surface 2b of the fiber optic plate 2 and the light-receiving surface 10a of the sensor panel 10, or the light-emitting surface 2b of the fiber optic plate 2 may be in contact with the light-receiving surface 10a of the sensor panel 10.

[0046] 1...scintillator unit, 2...fiber optic plate (support), 3...scintillator layer, 4...reflective layer (optical functional layer), 5...first organic layer (moisture-proof layer), 8...adhesive layer, 9...absorbing layer (optical functional layer), 10...sensor panel (support), 30...columnar crystal, 31...effective portion, 32...outer edge portion, S...gap.

Claims

1. A scintillator unit comprising: a support; a scintillator layer disposed on the support and including a plurality of columnar crystals; an optical function layer disposed on an effective portion of the scintillator layer; and a moisture-proof layer integrally covering the scintillator layer and the optical function layer, wherein the moisture-proof layer is in contact with the plurality of columnar crystals at the outer edge of the scintillator layer and penetrates into gaps between the plurality of columnar crystals.

2. The scintillator unit according to claim 1, wherein the thickness of the scintillator layer at the outer edge portion decreases toward the outside.

3. A scintillator unit according to claim 1 or 2, wherein the optical function layer is in contact with the effective portion of the scintillator layer.

4. The scintillator unit according to claim 1 or 2, further comprising an adhesive layer disposed between the effective portion of the scintillator layer and the optical function layer.

5. A scintillator unit according to any one of claims 1 to 4, wherein the optical function layer is a reflective layer that reflects light emitted from the scintillator layer in response to incident radiation.

6. A scintillator unit according to any one of claims 1 to 4, wherein the optical functional layer is an absorption layer that absorbs light emitted from the scintillator layer in response to incident radiation.

7. A scintillator unit according to any one of claims 1 to 6, wherein the support is a fiber optic plate.

8. The scintillator unit according to claim 7, further comprising a sensor panel disposed on the opposite side of said fiber optic plate from said scintillator layer.

9. A scintillator unit according to any one of claims 1 to 6, wherein the support is a sensor panel.

10. A method for manufacturing a scintillator unit, comprising the steps of: forming a scintillator layer including a plurality of columnar crystals on a support; arranging an optical function layer on an effective portion of the scintillator layer; and forming a moisture-proof layer that integrally covers the scintillator layer and the optical function layer by vapor deposition, with the optical function layer arranged on the effective portion of the scintillator layer and the outer edge portion of the scintillator layer exposed.

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