Patent Description:
The following technology is an example of known technology related to a radiographic imaging device. Japanese Patent Application Laid-Open (<CIT> (Patent Document <NUM>) describes a radiographic imaging device equipped with a radiographic image detection device body including a scintillator and a light detection section provided at the radiation-incident side of the scintillator, and also equipped with a support member disposed at the radiation-incident side of the radiographic image detection device body to support an imaging subject. The light detection section includes a thin film section to detect fluorescence as an electrical signal, and a reinforcement member provided on the opposite side of the thin film section to the scintillator. The reinforcement member and the support member are joined together so as to cohere along a joining face.

<CIT> (Patent Document <NUM>) describes a radiographic imaging device equipped with a scintillator panel including a scintillator and a support substrate to support the scintillator, a sensor panel including a light sensor configured to detect light converted by the scintillator and a sensor substrate provided with the light sensor, the sensor panel being stuck to the scintillator by a first bonding layer, and a reinforcing plate stuck to the support substrate by a second bonding layer.

<CIT> (Patent Document <NUM>) describes a radiation detector panel equipped with a case, a scintillator housed inside the case, and a light detection section disposed on a light-emitting side of the scintillator inside the case. The case is provided with a top plate that bends under load at a surface exposed to radiation. The scintillator includes plural upright columnar crystals, and the scintillator distorts with bending of the top plate. In a plane in which the columnar crystals are provided, gaps between the columnar crystals provided at a peripheral edge portion are wider than gaps between the columnar crystals provided at a central portion.

<CIT> and <CIT> disclose a radiation detector comprising: a flexible substrate; a plurality of pixels provided on the substrate and each including a photoelectric conversion element; a scintillator stacked on the substrate and including a plurality of columnar crystals; and a bending suppression member configured to suppress bending of the substrate. <CIT> discloses a similar radiation detector comprising a reinforcing member made from metal/resin mixture. Likewise, <CIT> discloses a similar radiation detector but with a reinforcement plate made from layered aluminium and carbon.

A known radiation detector employed in a radiographic imaging device includes a substrate, plural pixels provided on a front surface of the substrate, each of the pixels including a photoelectric conversion element, and a scintillator stacked on the substrate. In recent years flexible materials such as resin films are being employed as radiation detector substrate materials. In cases in which the substrate is flexible, for example, a concern arises that comparatively large localized bending of the substrate might occur due to the weight of the scintillator stacked on the substrate when the substrate is handled during processes to manufacture the radiation detector. In cases in which the scintillator includes plural columnar crystals, there is a concern that the scintillator might sustain damage due to mutually adjacent columnar crystals to contacting each other were significant bending of the substrate to occur.

An object of an aspect of technology disclosed herein is to reduce the risk of damage to a scintillator caused by a substrate bending due to the weight of the scintillator compared to cases lacking a bending suppression member having a rigidity prescribed according to the height, radius, and tip angle of columnar crystals configuring a scintillator as well as an interval between the columnar crystals.

A radiation detector according to the invention is defined by claim <NUM>.

In a radiation detector according to a second aspect of technology disclosed herein, the scintillator is stacked on a first surface side of the substrate, and the bending suppression member is stacked on at least one side of a second surface side of the substrate that is on the opposite side to the first surface side, or a side corresponding to a surface of the scintillator on the opposite side to a surface of the scintillator contacting the substrate.

In a radiation detector according to a third aspect of technology disclosed herein, the bending suppression member is stacked on both the second surface side of the substrate and the side corresponding to the surface of the scintillator on the opposite side to the surface of the scintillator contacting the substrate.

In a radiation detector according to a fourth aspect of technology disclosed herein, the bending suppression member has a higher rigidity than the substrate.

In a radiation detector according to a fifth aspect of technology disclosed herein, the bending suppression member extends so as to span a wider range than an extension range of the scintillator.

In a radiation detector according to a sixth aspect of technology disclosed herein, the substrate includes a connection region for a flexible wiring connection, and the bending suppression member is provided in a region covering at least a portion of the connection region and also covering the scintillator.

In a radiation detector according to the invention, the bending suppression member has a bending elastic modulus of from <NUM> MPa to <NUM> MPa.

In a radiation detector of according to an eighth aspect of technology disclosed herein, a ratio of a coefficient of thermal expansion of the bending suppression member against a coefficient of thermal expansion of the scintillator is from <NUM> to <NUM>.

In a radiation detector according to a ninth aspect of technology disclosed herein, a coefficient of thermal expansion of the bending suppression member is from <NUM> ppm/K to <NUM> ppm/K.

In a radiation detector according to a tenth aspect of technology disclosed herein, the bending suppression member is configured including at least one out of acrylic, polycarbonate, or polyethylene terephthalate.

A radiation detector according to the invention further includes a reinforcement member that is provided in a region straddling an end portion of the scintillator so as to reinforce a bending suppression effect of the bending suppression member.

In a radiation detector according to a twelfth aspect of technology disclosed herein, the reinforcement member has a higher rigidity than the substrate.

In a radiation detector according to a thirteenth aspect of technology disclosed herein, the reinforcement member is configured from a material that is the same as a material of the bending suppression member.

In a radiation detector according to a fourteenth aspect of technology disclosed herein, the substrate is configured including a resin film.

In a radiation detector according to a fifteenth aspect of technology disclosed herein, the substrate is configured including a base member made from a resin material including a fine particle layer containing fine particles of an inorganic material having a mean particle size of from <NUM> to <NUM>. The fine particle layer is provided on a second surface side of the substrate that is on the opposite side to a first surface of the substrate provided with the plural pixels.

In a radiation detector according to a sixteenth aspect of technology disclosed herein, the fine particles include an element having an atomic number that is greater than an atomic number of elements configuring the resin material and that is an atomic number not exceeding <NUM>.

In a radiation detector according to a seventeenth aspect of technology disclosed herein, the substrate has a coefficient of thermal expansion not greater than <NUM> ppm/K in a temperature range from <NUM> to <NUM>.

In a radiation detector according to an eighteenth aspect of technology disclosed herein, the substrate satisfies at least one condition out of having a heat shrinkage ratio in a machine direction at <NUM> and at a substrate thickness of <NUM> of not greater than <NUM>%, or having a modulus of elasticity at <NUM> of not less than <NUM> GPa.

A radiation detector according to a nineteenth aspect of technology disclosed herein further includes a buffer layer that is provided between the substrate and the scintillator and that has a coefficient of thermal expansion lying between the coefficient of thermal expansion of the substrate and the coefficient of thermal expansion of the scintillator.

In a radiation detector according to a twentieth aspect of technology disclosed herein, the scintillator includes a non-columnar portion on one end side of the columnar crystals, and the non-columnar portion is in contact with the substrate.

A radiographic imaging device according to a twenty-first aspect of technology disclosed herein includes the radiation detector of any one of the first to twentieth aspects, a reading section configured to perform reading of electrical charge accumulated in the pixels, and a generation section configured to generate image data based on the electrical charge read from the pixels.

A radiographic imaging device according to a twenty-second aspect of technology disclosed herein further includes a case that houses the radiation detector and that includes a radiation-incident face to which radiation is incident, and out of the substrate and the scintillator, the substrate is disposed on a side corresponding to the radiation-incident face.

A radiation detector manufacturing method according to the invention is defined by claim <NUM>.

In a manufacturing method according to a twenty-fourth aspect of technology disclosed herein, the bending suppression member has a rigidity satisfying R ≥ L - r/tanΦ + 4r × {(L - r/tanΦ)<NUM> - (d/<NUM>)<NUM>}<NUM>/<NUM>/d, wherein L is an average height of the columnar crystals, r is an average radius of the columnar crystals, d is an average interval between the columnar crystals, Φ is an average tip angle of the columnar crystals, and R is a radius of curvature of bending of the substrate due to the weight of the scintillator.

In a manufacturing method according to a twenty-fifth aspect of technology disclosed herein, the process of forming the scintillator includes a process of growing the columnar crystals on a front surface of the substrate using a vapor phase epitaxial method.

The first aspect of technology disclosed herein enables the risk of damage to the scintillator caused by bending occurring in the substrate due to the weight of the scintillator to be reduced in comparison to cases lacking a bending suppression member having a rigidity prescribed according to the height, radius, and tip angle of the columnar crystals as well as the interval between the columnar crystals.

The second aspect of technology disclosed herein enables a bending suppression effect to be effectively exhibited by the bending suppression member.

The third aspect of technology disclosed herein enables the risk of damage to the scintillator caused by bending of the substrate to be further reduced.

The fourth aspect of technology disclosed herein enables a bending suppression effect to be effectively exhibited by the bending suppression member.

The fifth aspect of technology disclosed herein enables a bending suppression effect to be effectively exhibited by the bending suppression member.

The sixth aspect of technology disclosed herein enables a bending suppression effect to be effectively exhibited by the bending suppression member.

The seventh aspect of technology disclosed herein enables a preferable rigidity to be achieved for the bending suppression member.

The eighth aspect of technology disclosed herein enables the risk of the substrate and the scintillator detaching from one another to be suppressed in comparison to cases in which the ratio of the coefficient of thermal expansion of the bending suppression member against the coefficient of thermal expansion of the scintillator does not lie in the stated range.

The ninth aspect of technology disclosed herein enables the risk of the substrate and the scintillator detaching from one another to be suppressed in comparison to cases in which the coefficient of thermal expansion of the bending suppression member does not lie in the stated range.

The tenth aspect of technology disclosed herein enables a bending suppression effect to be more effectively exhibited by the bending suppression member, and the risk of the substrate and the scintillator detaching from one another to be suppressed, in comparison to cases in which a configuration is adopted in which the bending suppression member is configured including another material.

The eleventh aspect of the technology disclosed herein enables bending of a portion of the substrate corresponding to the end portion of the scintillator to be suppressed in comparison to cases in which no reinforcement member is provided.

In the twelfth aspect of technology disclosed herein, an effect of reinforcing the bending suppression effect of the bending suppression member is effectively exhibited.

In the thirteenth aspect of technology disclosed herein, an effect of reinforcing the bending suppression effect of the bending suppression member is effectively exhibited.

The fourteenth aspect of technology disclosed herein enables a more lightweight and lower cost radiation detector to be achieved compared with cases in which a glass substrate is employed as the material for the substrate, and moreover enables the risk of impact damage to the substrate to be reduced.

The fifteenth aspect of technology disclosed herein enables back scattering radiation to be suppressed from being generated in the substrate in comparison to cases in which the substrate does not include a fine particle layer.

The sixteenth aspect of technology disclosed herein enables effective suppression of back scattering radiation while also enabling absorption of radiation in the fine particle layer to be suppressed in comparison to cases in which the atomic number of the fine particles is not within the stated range.

The seventeenth aspect of technology disclosed herein enables more appropriate pixel formation on the substrate than in cases in which the coefficient of thermal expansion of the substrate is not within the stated range.

The eighteenth aspect of technology disclosed herein enables more appropriate pixel formation on the substrate than in cases in which the heat shrinkage ratio and modulus of elasticity of the substrate are not within the stated ranges.

The nineteenth aspect of technology disclosed herein enables thermal stress to be suppressed from acting at the interface between the substrate and the scintillator in comparison to cases in which a buffer layer is not included.

In the twentieth aspect of technology disclosed herein, the non-columnar portion of the scintillator contacts the substrate, and the tips of the columnar crystals are on the front surface side of the scintillator. The technology disclosed herein is thus particularly effective in cases in which the tips of the columnar crystals are on the front surface side of the scintillator.

The twenty-first aspect of technology disclosed herein enables the risk of damage to the scintillator caused by bending occurring in the substrate due to the weight of the scintillator to be reduced in comparison to cases lacking a bending suppression member having a rigidity prescribed according to the height, radius, and tip angle of the columnar crystals as well as the interval between the columnar crystals.

The twenty-second aspect of technology disclosed herein enables a higher resolution of radiographic images to be achieved than in cases in which, from out of the substrate and the scintillator, the scintillator is disposed on the side of the radiation-incident face.

The twenty-third aspect of technology disclosed herein enables the risk of damage to the scintillator caused by bending occurring in the substrate due to the weight of the scintillator to be reduced in comparison to cases lacking a bending suppression member where the rigidity of the bending suppression member is a rigidity prescribed according to the height, radius, and tip angle of the columnar crystals as well as the interval between the columnar crystals.

The twenty-fourth aspect of technology disclosed herein enables a reduction in the risk of damage to the scintillator caused by bending occurring in the substrate due to the weight of the scintillator to be secured.

The twenty-fifth aspect of technology disclosed herein enables stable formation of the columnar crystals.

Explanation follows regarding examples of exemplary embodiments of technology disclosed herein, with reference to the drawings. Note that the same or equivalent configuration elements and portions are allocated the same reference numerals in each of the drawings.

<FIG> is a perspective view illustrating an example of configuration of a radiographic imaging device <NUM> according to an exemplary embodiment of technology disclosed herein. The radiographic imaging device <NUM> employs a portable electronic cassette format. The radiographic imaging device <NUM> is configured including a radiation detector <NUM> (flat panel detector (FPD)), a control unit <NUM>, a support plate <NUM>, and a case <NUM> housing the radiation detector <NUM>, the control unit <NUM>, and the support plate <NUM>.

The case <NUM> has, for example, a monocoque structure configured from carbon fiber reinforced plastic, which X-ray radiation and the like readily permeates, and is lightweight and highly durable. Radiation emitted from a radiation source (not illustrated in the drawings) and transmitted through an imaging subject (not illustrated in the drawings) is incident to a radiation-incident face <NUM> configuring an upper face of the case <NUM>. Inside the case <NUM>, the radiation detector <NUM> and the support plate <NUM> are arranged in this sequence from the radiation-incident face <NUM> side.

The support plate <NUM> is fixed to the case <NUM>, and supports a circuit board <NUM> (see <FIG>) to which is mounted an integrated circuit (IC) chip for performing signal processing and the like. The control unit <NUM> is arranged at an end portion inside the case <NUM>. The control unit <NUM> is configured including a battery (not illustrated in the drawings) and a controller <NUM> (see <FIG>).

<FIG> is a cross-section illustrating an example of a configuration of the radiographic imaging device <NUM>. The radiation detector <NUM> includes a flexible substrate <NUM>, plural pixels <NUM> that are provided on a front surface of the substrate <NUM> and that each include a photoelectric conversion element <NUM> (see <FIG>), and a scintillator <NUM> and a bending suppression member <NUM> to suppress bending of the substrate <NUM>, both stacked on the substrate <NUM>.

The substrate <NUM> is a flexible substrate that is capable of bending. In the present specification, reference to the substrate <NUM> being flexible means that when the rectangular substrate <NUM> is fixed at one side out of its four sides, then due to the weight of the substrate <NUM>, a height at a position <NUM> away from the fixed side of the substrate <NUM> will be at least <NUM> lower than the height of the fixed side. For example, a resin substrate, a metal foil substrate, or a thin glass sheet having a thickness of about <NUM> may be employed as the material of the substrate <NUM>. A resin film such as XENOMAX (registered trademark) or the like that is a highly heat-resistant polyimide film is particularly preferably employed therefor. Employing a resin film as the material of the substrate <NUM> enables a reduction in weight and a reduction in cost of the radiation detector <NUM> to be achieved compared to cases in which a glass substrate is employed as the material of the substrate <NUM>, and furthermore, the risk of impact damage to the substrate <NUM> can also be reduced. The plural pixels <NUM> are respectively provided on a first surface S1 of the substrate <NUM>.

The thickness of the substrate <NUM> depends on the hardness, size, and the like of the substrate <NUM>, and may be any thickness that enables the desired flexibility to be achieved. In cases in which the substrate <NUM> is configured including a base member made from a resin material, the thickness of the substrate <NUM> is, for example, preferably from <NUM> to <NUM>, and is more preferably from <NUM> to <NUM>.

Note that the coefficient of thermal expansion (CTE) of the substrate <NUM> in a temperature range of from <NUM> to <NUM> is preferably approximately the same as the coefficient of thermal expansion of the material configuring the photoelectric conversion element <NUM> (amorphous silicon, for example) (± approximately <NUM> ppm/K), and specifically is preferably not more than <NUM> ppm/K. Moreover, a heat shrinkage ratio in a machine direction (MD) of the substrate <NUM> at <NUM> and at a thickness of <NUM> is preferably not more than <NUM>%. Moreover, the substrate <NUM> preferably does not have a transition point in a temperature range of from <NUM> to <NUM>, as is typical of an ordinary polyimide, and preferably has a modulus of elasticity at <NUM> of not less than <NUM> GPa. The substrate <NUM> with the above characteristics is able to withstand thermal processing when forming the pixels <NUM> on the substrate <NUM>, and enables the pixels <NUM> to be formed on the substrate <NUM> in an appropriate manner.

Moreover, in cases in which the substrate <NUM> is configured including a base member formed from a resin material such as a polyimide or the like, as illustrated in <FIG>, the base member made from the resin material preferably includes a fine particle layer <NUM> containing plural fine particles 34P made from an inorganic material and having a mean particle size of from <NUM> to <NUM>. Moreover, the fine particle layer <NUM> is preferably provided on a second surface S2 of the substrate <NUM>, this being on the opposite side of the substrate <NUM> to the first surface S1 provided with the pixels <NUM>. Namely, the fine particles 34P are preferably present more toward the second surface S2 side of the substrate <NUM>. The fine particles 34P may sometimes cause indentations and protrusions on the front surface of the substrate <NUM>, making it difficult to form the pixels <NUM> on the front surface of the fine particle layer <NUM>. Arranging the fine particle layer <NUM> on the second surface S2 side of the substrate <NUM> enables the flatness of the first surface S1 to be secured, making it easier to form the pixels <NUM>.

The material of the fine particles 34P is preferably an inorganic material including an element having an atomic number that is greater than the atomic number of each element configuring the base member of the substrate <NUM>, but that is not more than <NUM>. For example, in cases in which the base member of the substrate <NUM> is configured from a resin material such as an polyimide or the like including C, H, O, and N, the fine particles 34P are preferably configured of an inorganic material including an element that has an atomic number greater than the atomic numbers of the elements configuring the resin material (i.e. C, H, O, and N) but that is not more than <NUM>. Specific examples of such fine particles 34P include SiO<NUM> that is an oxide of silicon of atomic number <NUM>, MgO that is an oxide of Mg of atomic number <NUM>, Al<NUM>O<NUM> that is an oxide of Al of atomic number <NUM>, and TiO<NUM> that is an oxide of Ti of atomic number <NUM>. XENOMAX (registered trademark) is a specific example of a resin sheet having the characteristics listed above and containing a fine particle layer <NUM>.

Note that the above thicknesses in the present exemplary embodiment are measured using a micrometer. The coefficient of thermal expansion is measured according to JIS K7197:<NUM>. In this measurement, test pieces are cut from a main face of the substrate <NUM> while changing the angle thereof by <NUM> degrees each time, the coefficient of thermal expansion is measured for each of the cut test pieces, and the highest value obtained is taken to be the coefficient of thermal expansion of the substrate <NUM>. The measurements of the coefficient of thermal expansion in the machine direction (MD) and the transverse direction (TD) are performed at <NUM> intervals over a range of from -<NUM> to <NUM> with ppm/°C converted into ppm/K. A TMA4000S instrument made by MAC Science Co. is employed to measure the coefficient of thermal expansion using a sample length of <NUM>, a sample width of <NUM>, an initial load of <NUM>/mm<NUM>, a speed of temperature increase of <NUM>/min, and an argon atmosphere. The modulus of elasticity is measured according to K7171:<NUM>. Note that in this measurement, test pieces are cut from a main face of the substrate <NUM> while changing the angle thereof by <NUM> degrees each time, a stretch test is performed on each of the cut test pieces, and the highest value obtained is taken to be the modulus of elasticity of the substrate <NUM>.

The scintillator <NUM> is stacked on the first surface S1 side of the substrate <NUM>. The scintillator <NUM> contains phosphors for converting irradiated radiation into light. The scintillator <NUM> is configured, for example, by an aggregation of columnar crystals including thallium-doped caesium iodide (CsI:Tl). The columnar crystals of CsI:Tl can be directly formed on the substrate <NUM> using, for example, a vapor phase epitaxial method. Forming the columnar crystals using a vapor phase epitaxial method enables stable formation of the columnar crystals. Note that the columnar crystals of CsI:Tl may be formed on a separate substrate from the substrate <NUM>, and then stuck to the substrate <NUM>. Each of the respective photoelectric conversion elements <NUM> (see <FIG>) configuring the plural pixels <NUM> generates an electrical charge based on the light emitted from the scintillator <NUM>.

A surface S3 of the scintillator <NUM> on the opposite side to a surface S6 that contacts the substrate <NUM>, and a surface S4 of the scintillator <NUM> that intersects with the surface S3, are covered by a reflective film <NUM>. The reflective film <NUM> has a function to reflect light generated in the scintillator <NUM> toward the substrate <NUM> side. Al<NUM>O<NUM> may, for example, be employed as the material of the reflective film <NUM>. The reflective film <NUM> covers the surface S3 and the surface S4 of the scintillator <NUM>, and also covers the substrate <NUM> at portions in the vicinity of the scintillator <NUM>. Note that the reflective film <NUM> may be omitted in cases in which a radiographic image of the desired quality can be obtained with the radiographic imaging device <NUM> without providing the reflective film <NUM>.

In the present exemplary embodiment, the substrate <NUM> is arranged at the radiation-incident side and the radiographic imaging device <NUM> employs an irradiation side sampling (ISS) imaging method. Adopting the irradiation side sampling method enables the distance been positions of intense light emission in the scintillator <NUM> and the pixels <NUM> to be shortened compared to when employing a penetration side sampling (PSS) method, in which the scintillator <NUM> is arranged at the radiation-incident side. This thereby enables radiographic images to be obtained with higher resolution. Note that the radiographic imaging device <NUM> may employ penetration side sampling.

The support plate <NUM> is arranged at the opposite side of the scintillator <NUM> to the radiation-incident side. A gap is provided between the support plate <NUM> and the scintillator <NUM>. The support plate <NUM> is fixed to side portions of the case <NUM>. The circuit board <NUM> is provided on the surface of the support plate <NUM> on the opposite side to the scintillator <NUM>. The circuit board <NUM> is mounted with a signal processor <NUM> for generating image data, an image memory <NUM> for storing the image data generated by the signal processor <NUM>, and the like.

The circuit board <NUM> and the substrate <NUM> are electrically connected together through a flexible cable <NUM> printed on a flexible printed circuit (FPC) and a tape carrier package (TCP) or a chip-on-film (COF). Charging amplifiers <NUM> for converting electrical charge read from the pixels <NUM> into electrical signals are mounted on the cable <NUM>. A gate line driver <NUM> (see <FIG>) that is electrically connected to the circuit board <NUM> and the substrate <NUM> is mounted to a separate flexible printed circuit not illustrated in <FIG>.

The bending suppression member <NUM> is stacked on the second surface S2 side of the substrate <NUM> on the opposite side to the first surface S1. The bending suppression member <NUM> has the role of imparting the substrate <NUM> with the necessary rigidity for the substrate <NUM> to support the scintillator <NUM>. Namely, providing the bending suppression member <NUM> suppresses the substrate <NUM> from bending due to the weight of the scintillator <NUM> compared to cases in which the bending suppression member <NUM> is omitted. The bending suppression member <NUM> extends over a wider range than an extension range of the scintillator <NUM>. Namely, a surface area of the bending suppression member <NUM> is larger than a surface area of the scintillator <NUM> in plan view, and the scintillator <NUM> is arranged at the inside of the extension range of the bending suppression member <NUM>. Thus, planar direction end portions of the bending suppression member <NUM> are positioned to the outside of planar direction end portions of the scintillator <NUM>. This enhances the effect of suppressing the substrate <NUM> from bending due to the weight of the scintillator <NUM>. The substrate <NUM> includes a connection region <NUM> where the flexible cable <NUM> is connected to an outer peripheral portion of the substrate <NUM>. The bending suppression member <NUM> is provided in a region covering at least a portion of the connection region <NUM> and also covering the scintillator <NUM>. Since the substrate <NUM> has a tendency to bend even in the connection region <NUM> where the cable <NUM> is connected, providing the bending suppression member <NUM> in the region covering at least a portion of the connection region <NUM> enables bending in the connection region <NUM> of the substrate <NUM> to be suppressed.

The bending suppression member <NUM> preferably has a higher rigidity than that of the substrate <NUM> from the perspective of being able to suppress bending of the substrate <NUM>. The bending suppression member <NUM> according to the invention is a member employing a material having a bending elastic modulus from <NUM> MPa to <NUM> MPa. By configuring the bending suppression member <NUM> from a material having a bending elastic modulus of <NUM> MPa or greater, functionality is effectively exhibited by the bending suppression member <NUM> to suppress bending of the substrate <NUM>. Configuring the bending suppression member <NUM> from a material having a bending elastic modulus of <NUM> MPa or lower means that, for example, after the bending suppression member <NUM> has been attached to the substrate <NUM> in a manufacturing process of the radiation detector <NUM>, when detaching a support body (not illustrated in the drawings) supporting the substrate <NUM> from the substrate, the support body can be easily detached from the substrate <NUM> by appropriately bending the substrate <NUM>. Note that the method employed to measure the bending elastic modulus may be the measurement method defined in JIS K <NUM>:<NUM>. Moreover, the bending rigidity of the bending suppression member <NUM> is preferably from <NUM> Pa·cm<NUM> to <NUM> Pa·cm<NUM>. The thickness of the bending suppression member <NUM> is preferably approximately <NUM>.

The coefficient of thermal expansion of the bending suppression member <NUM> is preferably from <NUM> ppm/K to <NUM> ppm/K. Moreover, the coefficient of thermal expansion of the bending suppression member <NUM> is preferably close to the coefficient of thermal expansion of the scintillator <NUM>. Specifically, a ratio of the coefficient of thermal expansion C2 of the bending suppression member <NUM> against the coefficient of thermal expansion C1 of the scintillator <NUM> (C2/C1) is preferably from <NUM> to <NUM>. Making the coefficient of thermal expansion of the bending suppression member <NUM> satisfy the conditions listed above enables the risk of the substrate <NUM> and the scintillator <NUM> detaching from each other, such as when heating or when heat is generated, to be suppressed. For example, the coefficient of thermal expansion of the scintillator <NUM> is <NUM> ppm/K in cases in which the scintillator <NUM> is configured mainly from CsI:Tl. In such cases, the following materials may be employed as the material of the bending suppression member <NUM>: polyvinyl chloride (PVC) having a coefficient of thermal expansion of from <NUM> ppm/K to <NUM> ppm/K, acrylic having a coefficient of thermal expansion of from <NUM> ppm/K to <NUM> ppm/K, polyethylene terephthalate (PET) having a coefficient of thermal expansion of from <NUM> ppm/K to <NUM> ppm/K, polycarbonate (PC) having a coefficient of thermal expansion of <NUM> ppm/K, TEFLON (registered trademark) having a coefficient of thermal expansion of from <NUM> ppm/K to <NUM> ppm/K, or the like. In consideration of the above bending elastic modulus, the material of the bending suppression member <NUM> preferably is a material including at least one out of acrylic, PET, or PC.

Other candidate materials that may be employed for the bending suppression member <NUM> include, for example, resins of polyphenylene sulfide (PPS), polyarylate (PAR), polysulfone (PSF), polyether sulfone (PES), polyetherimide (PEI), polyamide-imide (PAI), polyether ether ketone (PEEK), phenol resin, polytetrafluoroethylene, polychlorotrifluoroethylene, silicone resin, polyethylene naphthalate (PEN), and the like. A metal such as aluminum, iron, or an alloy thereof may also be employed as the material of the bending suppression member <NUM>. A layered body configured by stacking layers of resin and metal may also be employed as the material of the bending suppression member <NUM>. The surface S5 of the bending suppression member <NUM> on the opposite side to the face contacting the substrate <NUM> is stuck to an inner wall of the case <NUM> with a bonding layer <NUM> interposed therebetween.

<FIG> is a diagram illustrating an example of an electrical configuration of the radiographic imaging device <NUM>. Plural pixels <NUM> are arranged in a matrix formation on the first surface S1 of the substrate <NUM>. Each of the pixels <NUM> includes a photoelectric conversion element <NUM> and a thin film transistor (TFT) <NUM>. The photoelectric conversion element <NUM> generates electrical charge according to the light emitted from the scintillator <NUM>. The TFT <NUM> serves as a switching element that is switched to an ON state in order to read the electrical charge generated in the photoelectric conversion element <NUM>. The photoelectric conversion element <NUM> may, for example, be a photodiode configured from amorphous silicon.

Gate lines <NUM> and signal lines <NUM> are provided on the first surface S1 of the substrate <NUM>. The gate lines <NUM> extend in one direction (a row direction) that the pixels <NUM> are arrayed along. The signal lines <NUM> extend in a direction (a column direction) intersecting with the extension direction of the gate lines <NUM>. The pixels <NUM> are provided so as to correspond to the respective intersection portions between the gate lines <NUM> and the signal lines <NUM>.

Each of the gate lines <NUM> is connected to the gate line driver <NUM>. The gate line driver <NUM> performs reading of the electrical charge accumulated in the pixels <NUM> in response to a control signal supplied from the controller <NUM>. Each of the signal lines <NUM> is connected to a charging amplifier <NUM>. The charging amplifiers <NUM> are provided corresponding to each of the plural signal lines <NUM>. The charging amplifiers <NUM> generate electrical signals based on the electrical charge read from the pixels <NUM>. The output terminals of the charging amplifiers <NUM> are connected to the signal processor <NUM>. Based on the control signals supplied from the controller <NUM>, the signal processor <NUM> generates image data by performing specific processing on the electrical signals supplied from the charging amplifiers <NUM>. The image memory <NUM> is connected to the signal processor <NUM>. The image memory <NUM> stores the image data generated by the signal processor <NUM> based on the control signals supplied from the controller <NUM>.

The controller <NUM> has a wired or wireless connection to a radiation source via a communication section (not illustrated in the drawings), performs communication with a console (not illustrated in the drawings), and controls operation of the radiographic imaging device <NUM> by controlling the gate line driver <NUM>, the signal processor <NUM>, and the image memory <NUM>. The controller <NUM> may have a configuration including, for example, a microcomputer. Note that the gate line driver <NUM> is an example of a reading section of technology disclosed herein. The signal processor <NUM> is an example of a generation section of technology disclosed herein.

Explanation follows regarding an example of operation of the radiographic imaging device <NUM>. When radiation emitted from the radiation source (not illustrated in the drawings) and transmitted through an imaging subject is incident through the radiation-incident face <NUM> of the radiographic imaging device <NUM>, the scintillator <NUM> absorbs the radiation and emits visible light. The photoelectric conversion elements <NUM> configuring the respective pixels <NUM> convert the light emitted from the scintillator <NUM> into electrical charge. The electrical charge generated by each of the photoelectric conversion elements <NUM> is accumulated in the corresponding pixel <NUM>. The amount of electrical charge generated by the photoelectric conversion element <NUM> is reflected in a pixel value of the corresponding pixel <NUM>.

In order to generate a radiographic image, the gate line driver <NUM> supplies a gate signal to the TFTs <NUM> through gate lines <NUM> based on a control signal supplied from the controller <NUM>. The TFTs <NUM> are switched to the ON state by the gate signal in row units. Due to the TFTs <NUM> being switched to the ON state, the electrical charge accumulated in each of the pixels <NUM> is read through the corresponding signal line <NUM>, and is supplied to the corresponding charging amplifier <NUM>. The charging amplifiers <NUM> generate electrical signals based on the electrical charges read from the signal lines <NUM> and supply the generated electrical signals to the signal processor <NUM>.

The signal processor <NUM> is equipped with plural sample-and-hold circuits, a multiplexer, and an analogue-to-digital converter (none of which are illustrated in the drawings). The plural sample-and-hold circuits are provided so as to correspond to each of the respective plural signal lines <NUM>. The electrical signals supplied from the charging amplifiers <NUM> are held in the sample-and-hold circuits. The electrical signals held in the individual sample-and-hold circuits are each input to the analogue-to-digital converter through the multiplexer to be converted into digital signals. The signal processor <NUM> generates, as image data, data in which the digital signals generated by the analogue-to-digital converter are associated with information about the positions of the respective pixels <NUM>, and supplies this image data to the image memory <NUM>. The image memory <NUM> stores the image data generated by the signal processor <NUM>.

Due to the flexibility of the substrate <NUM>, there is a concern that comparatively large localized bending might occur in the substrate <NUM> due to the weight of the scintillator <NUM> when, for example, the substrate <NUM> is handled during processes to manufacture the radiation detector <NUM>. In cases in which the scintillator <NUM> includes plural columnar crystals, there is a concern that the scintillator <NUM> might sustain damage due to mutually adjacent columnar crystals contacting each other were significant bending of the substrate <NUM> to occur.

<FIG> is a diagram illustrating a state in which the substrate <NUM> has been bent into a circular arc shape such that two mutually adjacent columnar crystals 32a configuring the scintillator <NUM> contact each other. In <FIG>, R is the radius of curvature of the bending of the substrate <NUM>, and L is the average height of the columnar crystals 32a (also referred to as the average height L). Z is the average height of the columnar crystals 32a not including tips thereof. r is the average radius of the columnar crystals 32a (also referred to as the average radius r), Φ is the average angle of the tips of the columnar crystals 32a (also referred to as the average angle Φ), and d is the average interval between mutually adjacent columnar crystals 32a (also referred to as the average interval d). θ is the slope angle of a columnar crystal 32a as a result of the bending of the substrate <NUM>.

Since the interval d between the columnar crystals 32a corresponds to the length of the chord of a segment with a radius Z and a center angle of 2θ, Equation (<NUM>) below can be derived, and Equation (<NUM>) can be derived from Equation (<NUM>). <MAT> <MAT>.

Equation (<NUM>) below is established for the length D in <FIG>.

According to the Pythagoras theorem, Equation (<NUM>) below is established for the length h in <FIG>.

Equation (<NUM>) below is established for cosθ.

Substituting Equation (<NUM>) in Equation (<NUM>) and Equation (<NUM>) enables Equation (<NUM>) below to be derived.

Equation (<NUM>) is obtained by solving Equation (<NUM>) for the radius of curvature R.

Equation (<NUM>) below is established for Z. Equation (<NUM>) is obtained by substituting Equation (<NUM>) in Equation (<NUM>). <MAT> <MAT>.

According to Equation (<NUM>), there is a high possibility that mutually adjacent columnar crystals 32a will contact each other if the radius of curvature R of bending occurring in the substrate <NUM> satisfies Equation (<NUM>). Accordingly, limiting the radius of curvature R to the range defined by Equation (<NUM>) enables the risk of damage to the scintillator <NUM> as a result of the columnar crystals 32a contacting each other due to bending of the substrate <NUM> to be reduced in comparison to cases in which Equation (<NUM>) is not satisfied.

For example, in a case in which the average radius r of the columnar crystals 32a is <NUM>, the average height L of the columnar crystals 32a is <NUM>, the average angle Φ of the tips of the columnar crystals 32a is <NUM>°, and the average interval d between mutually adjacent columnar crystals 32a is no greater than <NUM>, then setting the radius of curvature R of bending of the substrate <NUM> to at least <NUM> enables the risk of damage to the scintillator <NUM> to be reduced. Since localized bending also presents a risk of damage, the use of a member capable of suppressing localized bending by preventing creases due to nicking or the like is also required.

In the radiation detector <NUM> according to the present exemplary embodiment, the rigidity of the bending suppression member <NUM> is set such that, in a fixed state to end portions of the substrate <NUM>, the radius of curvature R of bending that occurs in the substrate <NUM> due to the weight of the scintillator <NUM> satisfies Equation (<NUM>). In other words, the rigidity of the bending suppression member <NUM> is adjusted such that, in a fixed state to end portions of the substrate <NUM>, the radius of curvature R of the bending that occurs in the substrate <NUM> due to the weight of the scintillator <NUM> satisfies Equation (<NUM>). Namely, the rigidity of the bending suppression member <NUM> is prescribed according to the height, radius, and tip angle of the columnar crystals 32a configuring the scintillator <NUM>, and also the interval between the columnar crystals 32a. Adopting this approach enables the risk of the scintillator <NUM> being damaged by bending of the substrate <NUM> due to the weight of the scintillator <NUM> when, for example, the substrate <NUM> is handled during processes to manufacture the radiation detector <NUM>, to be reduced in comparison to cases in which Equation (<NUM>) is not satisfied. For example, since the permitted radius of curvature R becomes larger the greater the height L of the columnar crystals 32a, the higher the rigidity of the bending suppression member <NUM> employed.

The rigidity of the bending suppression member <NUM> may, for example, be adjusted using the thickness, density, elastic modulus, or the like of the bending suppression member <NUM>. Moreover, the rigidity of the bending suppression member <NUM> may also be adjusted by the selection of the material configuring the bending suppression member <NUM>.

Explanation follows regarding a method of manufacturing the radiation detector <NUM>. <FIG> are cross-sections illustrating an example of a method of manufacturing the radiation detector <NUM>.

Firstly, the plural pixels <NUM> are formed on the first surface S1 of the substrate <NUM> (<FIG>). Note that formation of the pixels <NUM> may be performed in a state in which the substrate <NUM> is supported by a support body (not illustrated in the drawings) to support the substrate <NUM>.

Next, the bending suppression member <NUM> is stuck to the second surface S2 of the substrate <NUM> on the opposite side to the first surface S1 of the substrate <NUM> (<FIG>). The bending suppression member <NUM> has a rigidity such that the radius of curvature R of bending that occurs in the substrate <NUM> due to the weight of the scintillator <NUM> satisfies Equation (<NUM>). Namely, the rigidity of the bending suppression member <NUM> is adjusted according to the average height L of the columnar crystals 32a, the average radius r of the columnar crystals 32a, the average interval d between the columnar crystals 32a, and the average angle Φ of the tips of the columnar crystals 32a. For example, the rigidity of the bending suppression member <NUM> is set higher the greater the average height L of the columnar crystals 32a.

Next, the scintillator <NUM> is formed on the first surface S1 of the substrate <NUM> (<FIG>). The scintillator <NUM> may be formed using, for example, a vapor phase epitaxial method, so as to directly grow columnar crystals of Tl-doped CsI on the substrate <NUM>.

<FIG> is a cross-section illustrating the columnar crystals 32a formed on the substrate <NUM>. In a vapor phase epitaxial method to form the columnar crystals 32a of CsI on the substrate <NUM> directly, a non-columnar portion 32b not configured by columnar crystals is formed on the substrate <NUM> in an initial growth stage, and the columnar crystals 32a are then formed on a foundation of the non-columnar portion 32b. In such cases, the non-columnar portion 32b is in contact with the substrate <NUM> and the tips of the columnar crystals 32a are disposed on a front surface side of the scintillator <NUM>. Note that columnar crystals of CsI:Tl may be formed on a separate substrate to the substrate <NUM> and then stuck to the substrate <NUM>. When employing such a method, the tips of the columnar crystals 32a contact the substrate <NUM> and the non-columnar portion 32b is on the front surface side of the scintillator <NUM>. In cases in which the tips of the columnar crystals 32a are on the front surface side of the scintillator <NUM>, the columnar crystals 32a are more susceptible to contacting each other due to bending of the substrate <NUM> than in cases in which the non-columnar portion 32b is on the front surface side of the scintillator <NUM>. The technology disclosed herein is therefore particularly effective when the former case is applied.

After forming the scintillator <NUM> on the substrate <NUM>, the reflective film <NUM> is then formed so as to cover the surface S3 of scintillator <NUM> on the opposite side to the surface S6 contacting the substrate <NUM>, and to cover the surface S4 that intersects with the surface S3 (<FIG>). Al<NUM>O<NUM> may, for example, be employed as the material of the reflective film <NUM>. The reflective film <NUM> is formed so as to cover the substrate <NUM> at portions as the vicinity of the scintillator <NUM>.

In the radiation detector <NUM> and the radiographic imaging device <NUM> according to the exemplary embodiment of technology disclosed herein, the rigidity of the bending suppression member <NUM> is set such that the radius of curvature R of bending that occurs in the substrate <NUM> due to the weight of the scintillator <NUM> satisfies Equation (<NUM>). Thus the radius of curvature R of bending that occurs in the substrate <NUM> due to the weight of the scintillator <NUM> is limited to the range of Equation (<NUM>). This thereby enables the risk of the scintillator <NUM> being damaged due to mutually adjacent columnar crystals 32a contacting each other when, for example, the substrate <NUM> is handled during processes to manufacture the radiation detector <NUM> to be reduced, even when bending occurs in the substrate <NUM> due to the weight of the scintillator <NUM>, compared to cases in which the technology disclosed herein is not applied.

<FIG> and <FIG> are cross-sections illustrating examples of a partial configuration of a radiographic imaging device <NUM> in which an ISS method is applied as the radiation sampling method. <FIG> and <FIG> each illustrate a case in which the substrate <NUM> is configured including a base member made from a resin material such as a polyimide or the like. <FIG> illustrates a case in which the substrate <NUM> contains the fine particle layer <NUM>, and <FIG> illustrates a case in which the substrate <NUM> does not contain a fine particle layer. In cases in which an ISS method is applied, from out of the substrate <NUM> and the scintillator <NUM> it is the substrate <NUM> that is arranged at the radiation-incident face <NUM> side of the case <NUM>. Namely, the radiation R incident to the radiation-incident face <NUM> is transmitted through the substrate <NUM> before being incident to the scintillator <NUM>.

When the radiation is incident to the substrate <NUM> containing a resin material with a configuration including elements having comparatively small atomic numbers, such as C, H, O, N, etc., a comparatively large amount of back scattering radiation Rb is generated by the Compton effect, which could leak out toward an imaging subject <NUM>. As illustrated in <FIG>, by providing the substrate <NUM> with the fine particle layer <NUM> that includes fine particles 34P configured from inorganic material including an element that has an atomic number greater than the atomic numbers of the elements configuring the resin material (i.e. C, H, O, and N), back scattering radiation Rb generated in the substrate <NUM> can be absorbed by the fine particle layer <NUM>. This enables the amount of back scattering radiation Rb leakage to the imaging subject <NUM> side to be suppressed in comparison to cases in which the substrate <NUM> does not include a fine particle layer (see <FIG>). Note that the higher the atomic numbers of the elements configuring the fine particles 34P, the greater the effect of absorbing the back scattering radiation Rb increases. However, the amount of radiation absorbed also increases and thus the amount of radiation reaching the scintillator <NUM> decreases. The atomic numbers of the elements configuring the fine particles 34P are thus preferably not higher than <NUM>.

Although an example has been described of a case in which the bending suppression member <NUM> is provided on the second surface S2 side of the substrate <NUM> in the exemplary embodiment described above, the technology disclosed herein is not limited this approach. For example, as illustrated in <FIG>, the bending suppression member <NUM> may be stacked on the surface S3 side of the scintillator <NUM> that is the opposite side to the surface S6 in contact with the substrate <NUM>. Adopting such a configuration enables substantially the same advantageous effects to be obtained to cases in which the bending suppression member <NUM> is provided on the second surface S2 side of the substrate <NUM>.

Moreover, as illustrated in <FIG>, the bending suppression member <NUM> may be stacked on both the second surface S2 side of the substrate <NUM> and on the surface S3 side of the scintillator <NUM> that is the opposite side to the surface S6 in contact with the substrate <NUM>. Stacking the bending suppression member <NUM> on at least one side from out of the second surface S2 side of the substrate <NUM> or the surface S3 side of the scintillator <NUM> that is the opposite side to the surface S6 in contact with the substrate <NUM> enhances the bending suppression effect exhibited by the bending suppression member <NUM>. Moreover, as illustrated in <FIG>, stacking a bending suppression member <NUM> on both the second surface S2 side of the substrate <NUM> and the surface S3 side of the scintillator <NUM> enables the bending suppression effect exhibited by the bending suppression member <NUM> to be enhanced, enabling the risk of the scintillator <NUM> being damaged by bending of the substrate <NUM> to be reduced further. In cases in which bending suppression members <NUM> are stacked on both the second surface S2 side of the substrate <NUM> and the surface S3 side of the scintillator <NUM>, the bending suppression member <NUM> stacked on the second surface S2 side of the substrate <NUM>, this being the radiation-incident side, preferably absorbs a lower amount of radiation than the bending suppression member <NUM> stacked on the surface S3 side of the scintillator <NUM>.

<FIG> is a cross-section illustrating an example of a configuration of a radiation detector 30A according to a second exemplary embodiment of technology disclosed herein. The radiation detector 30A differs from the radiation detector <NUM> according to the first exemplary embodiment in the point that, like the presently claimed invention, reinforcement members <NUM> are further included in order to reinforce the bending suppression effect of the bending suppression member <NUM>.

In the configuration illustrated in <FIG>, the bending suppression member <NUM> is provided on the second surface S2 side of the substrate <NUM>, and the reinforcement member <NUM> is provided on the surface S5 side of the bending suppression member <NUM>, this being on the opposite side to the surface of the bending suppression member <NUM> contacting the substrate <NUM>. The reinforcement members <NUM> are provided in regions straddling planar direction end portions (outer edges, edges) 32E of the scintillator <NUM>. Namely, the reinforcement members <NUM> are provided to the bending suppression member <NUM> on the surface S5 side of the bending suppression member <NUM> in a state straddling a boundary between regions where the scintillator <NUM> is present and regions were the scintillator <NUM> is not present. The reinforcement members <NUM> preferably have a higher rigidity than that of the substrate <NUM> from the perspective of reinforcing the bending suppression effect of the bending suppression member <NUM>. Preferable ranges for the bending elastic modulus and the coefficient of thermal expansion of the reinforcement members <NUM> are the same as those for the bending suppression member <NUM>. The reinforcement members <NUM> may, for example, be configured from the same material as the bending suppression member <NUM>, or may be configured from a material having a higher rigidity than that of the bending suppression member <NUM>.

<FIG> is a cross-section illustrating an example of a state in which the substrate <NUM> has bent due to the weight of the scintillator <NUM>. As illustrated in <FIG>, at regions of the substrate <NUM> over which the scintillator <NUM> extends, the amount of bending of the substrate <NUM> is comparatively small due to the rigidity of the scintillator <NUM>. However, at the portions of the substrate <NUM> corresponding to the end portions 32E of the scintillator <NUM>, the amount of bending of the substrate <NUM> is comparatively large. At the portions where the amount of bending of the substrate <NUM> is large, the risk of the scintillator <NUM> being damaged is higher than at portions where the amount of bending is small.

In the radiation detector 30A according to the second exemplary embodiment of the technology disclosed herein, the reinforcement members <NUM> are provided in regions straddling the end portions 32E of the scintillator <NUM> in order to reinforce the bending suppression effect of the bending suppression member <NUM>. This enables the bending of the portions of the substrate <NUM> corresponding to the end portions 32E of the scintillator <NUM> to be suppressed compared to cases in which the reinforcement members <NUM> are not provided. Thus the risk of the scintillator <NUM> being damaged can be reduced compared to cases in which the reinforcement members <NUM> are not provided.

Note that as illustrated in <FIG>, the reinforcement members <NUM> may be provided on the second surface S2 of the substrate <NUM> in cases in which the bending suppression member <NUM> is provided on the surface S3 of the scintillator <NUM> on the opposite side to the surface S6 in contact with the substrate <NUM>. Moreover, as illustrated in <FIG>, the reinforcement members <NUM> may be provided on the surface S5 of the bending suppression member <NUM> on the opposite side to the side of the face in contact with the substrate <NUM> in cases in which the bending suppression members <NUM> are provided on both the second surface S2 of the substrate <NUM> and on the surface S3 of the scintillator <NUM>. In either of the configurations illustrated in <FIG>, the reinforcement members <NUM> are provided in regions straddling the end portions (outer edges, edges) 32E of the scintillator <NUM>. Namely, in the configuration illustrated in <FIG>, the reinforcement members <NUM> are provided to the substrate <NUM> on the second surface S2 side of the substrate <NUM> in a state straddling boundaries between the region where the scintillator <NUM> is present and regions where the scintillator <NUM> is not present. In the configuration illustrated in <FIG>, the reinforcement members <NUM> are provided to the bending suppression member <NUM> on the surface S5 side of the bending suppression member <NUM> in a state straddling boundaries between the region where the scintillator <NUM> is present and regions where the scintillator <NUM> is not present.

<FIG> is a cross-section illustrating an example of a configuration of a radiation detector 30B according to a third exemplary embodiment of technology disclosed herein. The radiation detector 30B includes a buffer layer <NUM> provided between the substrate <NUM> and the scintillator <NUM>. The buffer layer <NUM> has a coefficient of thermal expansion lying between the coefficient of thermal expansion of the substrate <NUM> and the coefficient of thermal expansion of the scintillator <NUM>. A polyimide film or a parylene film may be employed, for example, as the buffer layer <NUM>. In cases in which XENOMAX (registered trademark) is employed as the material of the substrate <NUM>, there is a larger difference between the coefficients of thermal expansion of the substrate <NUM> and the scintillator <NUM> than in cases in which, for example, a glass substrate is employed as the substrate <NUM>. Thermal stress acting at the interface between the substrate <NUM> and the scintillator <NUM> would accordingly be excessive. Providing the buffer layer <NUM> between the substrate <NUM> and the scintillator <NUM> enables such thermal stress to be suppressed from acting at the interface between the substrate <NUM> and the scintillator <NUM>.

<FIG> are each cross-sections illustrating examples of installation embodiments of the bending suppression member <NUM> in cases in which the bending suppression member <NUM> is stacked on the side of the surface of the scintillator <NUM> on the opposite side to the surface in contact with the substrate <NUM>. In <FIG>, a region where plural pixels <NUM> are provided on the substrate <NUM> is denoted a pixel region 41A.

In cases in which the scintillator <NUM> is formed using a vapor deposition method, as illustrated in <FIG>, the scintillator <NUM> is formed with a slope with a gradually decreasing thickness on progression toward an outer edge thereof. In the following explanation, a central region of the scintillator <NUM> where the thickness may be regarded as substantially constant if manufacturing error and measurement error are ignored is referred to as a central portion 33A. Moreover, an outer peripheral region of the scintillator <NUM> where the thickness is, for example, not more than <NUM>% of the average thickness of the central portion 33A of the scintillator <NUM> is referred to as a peripheral edge portion 33B. Namely, the scintillator <NUM> includes a sloping face that slopes with respect to the substrate <NUM> at the peripheral edge portion 33B.

As illustrated in <FIG>, an adhesion layer <NUM>, a reflective film <NUM>, a bonding layer <NUM>, a protective layer <NUM>, and a bonding layer <NUM> may be provided between the scintillator <NUM> and the bending suppression member <NUM>.

The adhesion layer <NUM> covers the entire front surface of the scintillator <NUM>, including the central portion 33A and the peripheral edge portion 33B of the scintillator <NUM>. The adhesion layer <NUM> includes a function to fix the reflective film <NUM> to the scintillator <NUM>. The adhesion layer <NUM> preferably has light-transmitting properties. Examples of materials that may be employed for the adhesion layer <NUM> include acrylic-based adhesives, hot-melt-based adhesives, silicone-based bonding agents, and the like. Examples of acrylic-based adhesives include, for example, urethane acrylates, acrylic resin acrylates, epoxy acrylates, and the like. Examples of hot-melt-based adhesives include thermoplastic plastics such as copolymer resins of ethylene vinyl acetate (EVA), copolymer resins of ethylene and acrylic acid (EAA), copolymer resins of ethylene and ethyl acrylate (EEA), copolymers of ethylene/methyl methacrylate (EMMA), and the like. The thickness of the adhesion layer <NUM> is preferably from <NUM> to <NUM>. Making the thickness of the adhesion layer <NUM> not less than <NUM> enables the effect of fixing the reflective film <NUM> to the scintillator <NUM> to be sufficiently exhibited. Furthermore, this also enables the risk of an air layer being formed between the scintillator <NUM> and the reflective film <NUM> to be suppressed. Were an air layer to be formed between the scintillator <NUM> and the reflective film <NUM>, then there would be concern that multiple reflection of the light emitted from the scintillator <NUM> might occur, with the light being repeatedly reflected between the air layer and the scintillator <NUM>, and between the air layer and the reflective film <NUM>. Moreover, making the thickness of the adhesion layer <NUM> not greater than <NUM> enables a reduction in modulation transfer function (MTF) and detective quantum efficiency (DQE) to be suppressed.

The reflective film <NUM> covers the entire front surface of the adhesion layer <NUM>. The reflective film <NUM> has a function of reflecting the light converted in the scintillator <NUM>. The reflective film <NUM> is preferably configured from an organic material. Examples of materials that may be employed for the reflective film <NUM> include white polyethylene terephthalate (PET), TiO<NUM>, Al<NUM>O<NUM>, foamed white PET, polyester-based high reflectivity sheets, specular reflective aluminum, and the like. Note that white PET is PET to which a white pigment, such as TiO<NUM>, barium sulfate, or the like, has been added. Moreover, polyester-based high reflectivity sheets are sheets (films) having a multi-layer structure of plural superimposed thin polyester sheets. Foamed white PET is white PET having a porous surface. The thickness of the reflective film <NUM> is preferably from <NUM> to <NUM>.

The bonding layer <NUM> covers the entire front surface of the reflective film <NUM>. The end portion of the bonding layer <NUM> also extends as far as the front surface of the substrate <NUM>. Namely, the bonding layer <NUM> is bonded to the substrate <NUM> at these end portions. The bonding layer <NUM> has a function to fix the reflective film <NUM> and the protective layer <NUM> to the scintillator <NUM>. The same materials as may be employed in the adhesion layer <NUM> may be employed as the material of the bonding layer <NUM>. However, the bonding strength of the bonding layer <NUM> is preferably greater than the bonding strength of the adhesion layer <NUM>.

The protective layer <NUM> covers the entire front surface of the bonding layer <NUM>. Namely, the protective layer <NUM> is provided so as to cover the entirety of the scintillator <NUM>, and an end portion of the protective layer <NUM> also covers a portion of the substrate <NUM>. The protective layer <NUM> functions as a moisture-proof film to prevent the ingress of moisture into the scintillator <NUM>. Examples of materials that may be employed as the material of the protective layer <NUM> include organic films including an organic material, such as PET, polyphenylene sulfide (PPS), oriented polypropylene (OPP), polyethylene naphthalate (PEN), polyimide (PI), and the like. Moreover, an ALPET (registered trademark) sheet in which an aluminum layer such as an aluminum foil is bonded to an insulating sheet (film) such as polyethylene terephthalate may be employed as the protective layer <NUM>.

The bending suppression member <NUM> is provided on the front surface of the protective layer <NUM>, with the bonding layer <NUM> interposed therebetween. The same materials as may be employed in the adhesion layer <NUM> and the bonding layer <NUM> may, for example, be employed as the material of the bonding layer <NUM>.

In the example illustrated in <FIG>, the bending suppression member <NUM> extends over regions corresponding to the central portion 33A and the peripheral edge portion 33B of the scintillator <NUM>, with an outer peripheral portion of the bending suppression member <NUM> angled so as to follow the slope of the peripheral edge portion 33B of the scintillator <NUM>. The bending suppression member <NUM> is bonded to the protective layer <NUM> through the bonding layer <NUM> at both the region corresponding to the central portion 33A of the scintillator <NUM> and the region corresponding to the peripheral edge portion 33B of the scintillator <NUM>. In the example illustrated in <FIG>, an end portion of the bending suppression member <NUM> is disposed in a region corresponding to the peripheral edge portion 33B of the scintillator <NUM>.

As illustrated in <FIG>, the bending suppression member <NUM> may be provided only in the region corresponding to the central portion 33A of the scintillator <NUM>. In such cases, the bending suppression member <NUM> is bonded to the protective layer <NUM> through the bonding layer <NUM> in the region corresponding to the central portion 33A of the scintillator <NUM>.

As illustrated in <FIG>, in cases in which the bending suppression member <NUM> extends over regions corresponding to both the central portion 33A and the peripheral edge portion 33B of the scintillator <NUM>, the bending suppression member <NUM> may be configured without providing an angled portion to follow the slope of the outer peripheral portions of the scintillator <NUM>. In such cases, the bending suppression member <NUM> is bonded to the protective layer <NUM> through the bonding layer <NUM> in the region corresponding to the central portion 33A of the scintillator <NUM>. A space corresponding to the slope of the peripheral edge portion 33B of the scintillator <NUM> is formed between the scintillator <NUM> (the protective layer <NUM>) and the bending suppression member <NUM> in the region corresponding to the peripheral edge portion 33B of the scintillator <NUM>.

In this example the cable <NUM> is connected to terminals <NUM> provided in the connection region <NUM> at the outer peripheral portion of the substrate <NUM>. The substrate <NUM> is connected to a control board (see <FIG>) through the cable <NUM>. There is a concern that the cable <NUM> might detach from the substrate <NUM> or positional misalignment might arise were bending of the substrate <NUM> to occur. In such cases it would be necessary to perform a task to reconnect the cable <NUM> and the substrate <NUM>. This task to reconnect the cable <NUM> and the substrate <NUM> is called re-work. As illustrated in <FIG>, by arranging the end portion of the bending suppression member <NUM> at the inside of the end portion of the scintillator <NUM>, re-work can be performed more easily than in cases in which the bending suppression member <NUM> extends to the vicinity of the connection region <NUM>.

As illustrated in <FIG>, the end portion of the bending suppression member <NUM> may be disposed outside the end portion of the scintillator <NUM>, and the end portions of the bonding layer <NUM> and the protective layer <NUM> that both extend onto the substrate <NUM> may be provided so as to be aligned with each other. Note that there is no need for the position of the end portion of the bending suppression member <NUM> to align exactly with the position of the end portions of the bonding layer <NUM> and the protective layer <NUM>.

In the example illustrated in <FIG>, the bending suppression member <NUM> is bonded to the protective layer <NUM> through the bonding layer <NUM> in the region corresponding to the central portion 33A of the scintillator <NUM>, and a space corresponding to the slope at the peripheral edge portion 33B of the scintillator <NUM> is formed between the scintillator <NUM> (the protective layer <NUM>) and the bending suppression member <NUM> in the region corresponding to the peripheral edge portion 33B of the scintillator <NUM> and also in a region further to the outside thereof.

In the example illustrated in <FIG>, a filler <NUM> is provided in the space formed between the scintillator <NUM> (the protective layer <NUM>) and the bending suppression member <NUM> at the region corresponding to the peripheral edge portion 33B of the scintillator <NUM> and also at the region further to the outside thereof. The material of the filler <NUM> is not particularly limited, and examples of materials that may be employed therefor include, for example, resins. Note that in the example illustrated in <FIG> the bonding layer <NUM> is provided in the entire region between the bending suppression member <NUM> and the filler <NUM> in order to fix the bending suppression member <NUM> to the filler <NUM>.

The method of forming the filler <NUM> is not particularly limited. For example, after forming the bonding layer <NUM> and the bending suppression member <NUM> in sequence on the scintillator <NUM> covered by the adhesion layer <NUM>, the reflective film <NUM>, the bonding layer <NUM>, and the protective layer <NUM>, a flowable filler <NUM> may be poured into be the space formed between the scintillator <NUM> (the protective layer <NUM>) and the bending suppression member <NUM>, and the filler <NUM> then cured. Moreover, for example, after forming the scintillator <NUM>, the adhesion layer <NUM>, the reflective film <NUM>, the bonding layer <NUM>, and the protective layer <NUM> in sequence on the substrate <NUM>, the filler <NUM> may be formed, and the bonding layer <NUM> and the bending suppression member <NUM> may then be formed in sequence so as to cover the scintillator <NUM> covered by the adhesion layer <NUM>, the reflective film <NUM>, the bonding layer <NUM>, and the protective layer <NUM> and also cover the filler <NUM>.

By filling the filler <NUM> into the space formed between the scintillator <NUM> (the protective layer <NUM>) and the bending suppression member <NUM> in this manner, the bending suppression member <NUM> and the scintillator <NUM> (the protective layer <NUM>) can be better suppressed from detaching from one another than in the embodiment illustrated in <FIG>. Furthermore, due to adopting a structure in which the scintillator <NUM> is fixed to the substrate <NUM> by both the bending suppression member <NUM> and the filler <NUM>, the scintillator <NUM> from the substrate <NUM> can be suppressed from detaching from one another.

In the example illustrated in <FIG>, the outer peripheral portion of the bending suppression member <NUM> is angled so as to follow the slope of the peripheral edge portion 33B of the scintillator <NUM>, and so as also to cover the portions of the bonding layer <NUM> and the protective layer <NUM> that cover the substrate <NUM>. Moreover, the end portion of the bending suppression member <NUM> and the end portions of the bonding layer <NUM> and the protective layer <NUM> are aligned with each other. Note that there is no need for the position of the end portion of the bending suppression member <NUM> to align exactly with the position of the end portions of the bonding layer <NUM> and the protective layer <NUM>.

The end portions of the bending suppression member <NUM>, the bonding layer <NUM>, the protective layer <NUM>, and the bonding layer <NUM> are sealed with a sealing member <NUM>. The sealing member <NUM> is preferably provided in a region spanning from the front surface of the substrate <NUM> to the front surface of the bending suppression member <NUM>, and in a region not covering the pixel region 41A. Resins may be employed as the material of the sealing member <NUM>, and thermoplastic resins are particularly preferably employed therefor. Specifically glues such as acrylic glues, urethane based glues, and the like may be employed as the sealing member <NUM>. The bending suppression member <NUM> has a higher rigidity than that of the protective layer <NUM>, and there is a concern that recovery force due to the angle attempting to straighten out at the angled portion of the bending suppression member <NUM> might act to cause the protective layer <NUM> to detach. Sealing the end portions of the bending suppression member <NUM>, the bonding layer <NUM>, the protective layer <NUM>, and the bonding layer <NUM> using the sealing member <NUM> enables such detachment of the protective layer <NUM> to be suppressed.

Similarly to in the embodiment illustrated in <FIG>, in the example illustrated in <FIG>, the filler <NUM> is provided in a space formed between the scintillator <NUM> (the protective layer <NUM>) and the bending suppression member <NUM> at the region corresponding to the peripheral edge portion 33B of the scintillator <NUM> and also at the region further to the outside thereof. Moreover, in the region corresponding to the end portion of the scintillator <NUM> an additional and separate bending suppression member 60A is stacked on the front surface of the bending suppression member <NUM> with a bonding layer 54A interposed therebetween. More specifically, the bending suppression member 60A is provided in a region straddling the end portion (outer edge, edge) of the scintillator <NUM>. The bending suppression member 60A may be configured from the same materials as the bending suppression member <NUM>. As illustrated in <FIG>, the amount of bending of the substrate <NUM> is comparatively large at the end portions of the scintillator <NUM>. Forming a multi-layer structure using the bending suppression members <NUM> and 60A at the region corresponding to the end portion of the scintillator <NUM> enables the effect of suppressing bending of the substrate <NUM> at the end portion of the scintillator <NUM> to be enhanced.

As illustrated in <FIG>, in cases in which the end portion of the bending suppression member <NUM> is arranged further to the outside than the end portion of the scintillator <NUM> and is provided so as to be aligned with the end portions of the bonding layer <NUM> and the protective layer <NUM>, re-work can also be performed more easily than in cases in which the bending suppression member <NUM> extends as far as the vicinity of the connection region <NUM>.

As illustrated in <FIG>, a configuration may be adopted in which the end portion of the bending suppression member <NUM> is provided so as to be positioned further outside than the end portions of the bonding layer <NUM> and the protective layer <NUM> that extend onto the substrate <NUM>, and so as to be positioned at the inside of the end portion of the substrate <NUM>.

In the example illustrated in <FIG>, the bending suppression member <NUM> is bonded to the protective layer <NUM> through the bonding layer <NUM> at the region corresponding to the central portion 33A of the scintillator <NUM>, and in the region corresponding to the peripheral edge portion 33B of the scintillator <NUM> and also in the region further to the outside thereof a space corresponding to the slope of the peripheral edge portion 33B of the scintillator <NUM> is formed between the scintillator <NUM> (the protective layer <NUM>) and the bending suppression member <NUM>, and between the substrate <NUM> and the bending suppression member <NUM>.

In the example illustrated in <FIG>, the end portion of the bending suppression member <NUM> is supported by a spacer <NUM>. Namely, one end of the spacer <NUM> is connected to the first surface S1 of the substrate <NUM>, and the other end of the spacer <NUM> is connected to the end portion of the bending suppression member <NUM> through a bonding layer <NUM>. By supporting the end portion of the bending suppression member <NUM> that extends so as to form a space between itself and the substrate <NUM> using the spacer <NUM>, detachment of the bending suppression member <NUM> can be suppressed. Moreover, the bending suppression effect from the bending suppression member <NUM> can be caused to act as far as the vicinity of the end portion of the substrate <NUM>. Note that instead of providing the spacer <NUM>, a filler may be filled into the space formed between the scintillator <NUM> (the protective layer <NUM>) and the bending suppression member <NUM>, and between the substrate <NUM> and the bending suppression member <NUM>, in a similar manner to the example illustrated in <FIG>.

In the example illustrated in <FIG>, the outer peripheral portion of the bending suppression member <NUM> is angled so as to follow the slope at the peripheral edge portion 33B of the scintillator <NUM>, and the outer peripheral portion of the bending suppression member <NUM> covers the portion where the bonding layer <NUM> and the protective layer <NUM> cover the substrate <NUM> and also covers the substrate <NUM> at the outside thereof. Namely, the end portions of the bonding layer <NUM> and the protective layer <NUM> are sealed by the bending suppression member <NUM>. The portions of the bending suppression member <NUM> that extend over the substrate <NUM> are bonded to the substrate <NUM> though the bonding layer <NUM>. By covering the end portions of the bonding layer <NUM> and the protective layer <NUM> using the bending suppression member <NUM> in this manner, detachment of the protective layer <NUM> can be suppressed. Note that a sealing member may be employed to seal the end portions of the bending suppression member <NUM>, in a similar manner to the example illustrated in <FIG>.

In the example illustrated in <FIG>, in an embodiment in which the end portion of the bending suppression member <NUM> is supported by the spacer <NUM>, an additional and separate bending suppression member 60A is stacked on a front surface of the bending suppression member <NUM> at a region corresponding to the end portion of the scintillator <NUM>, with a bonding layer 54A interposed therebetween. More specifically, the bending suppression member 60A is provided in a region straddling the end portion (outer edge, edge) of the scintillator <NUM>. The bending suppression member 60A may be configured from the same materials as the bending suppression member <NUM>. As illustrated in <FIG>, the amount of bending of the substrate <NUM> is comparatively large at the end portions of the scintillator <NUM>. Forming a multi-layer structure using the bending suppression members <NUM> and 60A at the region corresponding to the end portion of the scintillator <NUM> enables the effect of suppressing bending of the substrate <NUM> to be enhanced at the end portion of the scintillator <NUM>. Note that instead of providing the spacer <NUM>, a filler may be filled into the space formed between the scintillator <NUM> (the protective layer <NUM>) and the bending suppression member <NUM>, and between the substrate <NUM> and the bending suppression member <NUM>, in a similar manner to the example illustrated in <FIG>.

As illustrated in <FIG>, the end portion of the bending suppression member <NUM> may be provided so as to be aligned with the end portion of the substrate <NUM>. Note that there is no need for the position of the end portion of the bending suppression member <NUM> to align exactly with the position of the end portion of the substrate <NUM>.

In the example illustrated in <FIG>, the bending suppression member <NUM> is bonded to the protective layer <NUM> through the bonding layer <NUM> at a region corresponding to the central portion 33A of the scintillator <NUM>, and a space corresponding to the slope of the peripheral edge portion 33B of the scintillator <NUM> is formed between the scintillator <NUM> (the protective layer <NUM>) and the bending suppression member <NUM>, and between the substrate <NUM> and the bending suppression member <NUM>, at a region corresponding to the peripheral edge portion 33B of the scintillator <NUM> and also at a region further to the outside thereof.

In the example illustrated in <FIG>, the end portion of the bending suppression member <NUM> is supported by the spacer <NUM>. Namely, one end of the spacer <NUM> is connected to the cable <NUM> provided at the end portion of the substrate <NUM>, and the other end of the spacer <NUM> is connected to the end portion of the bending suppression member <NUM> through a bonding layer <NUM>. By using the spacer <NUM> to support the end portion of the bending suppression member <NUM> that extends so as to form a space between itself and the substrate <NUM>, detachment of the bending suppression member <NUM> can be suppressed. Moreover, the bending suppression effect from the bending suppression member <NUM> can be caused to act as far as the vicinity of the end portion of the substrate <NUM>.

In the example illustrated in <FIG>, the space formed between the scintillator <NUM> (the protective layer <NUM>) and the bending suppression member <NUM>, and between the substrate <NUM> and the bending suppression member <NUM>, is filled by the filler <NUM>. In the present exemplary embodiment the connection portions between the cable <NUM> and the terminals <NUM> are covered by the filler <NUM>. Thus by filling the space formed between the scintillator <NUM> (the protective layer <NUM>) and the bending suppression member <NUM>, and between the substrate <NUM> and the bending suppression member <NUM>, with the filler <NUM>, the bending suppression member <NUM> and the scintillator <NUM> (the protective layer <NUM>) can be better suppressed from detaching from one another than in the embodiment illustrated in <FIG>. Furthermore, due to the scintillator <NUM> having a structure fixed to the substrate <NUM> by both the bending suppression member <NUM> and the filler <NUM>, the scintillator <NUM> and the substrate <NUM> can be suppressed from detaching from one another. Moreover, since the connection portions between the cable <NUM> and the terminals <NUM> are covered by the filler <NUM>, detachment of the cable <NUM> can also be suppressed.

In the example illustrated in <FIG>, the outer peripheral portion of the bending suppression member <NUM> is angled so as to follow the slope of the peripheral edge portion 33B of the scintillator <NUM>. The outer peripheral portion of the bending suppression member <NUM> also covers a portion where the bonding layer <NUM> and the protective layer <NUM> cover the substrate <NUM>, a portion of the substrate at the outside thereof, and the connection portion between the cable <NUM> and the terminals <NUM>. The portions of the bending suppression member <NUM> extending over the substrate <NUM> and over the cable <NUM> are respectively bonded to the substrate <NUM> and the cable <NUM> through the bonding layer <NUM>. The connection portions between the cable <NUM> and the terminals <NUM> are covered by the bending suppression member <NUM>, enabling detachment of the cable <NUM> to be suppressed. Moreover, since the other end of the cable <NUM> is anticipated to be connected to a control board mounted with electronic components, there is a concern regarding comparatively large bending of the substrate <NUM> occurring at the connection portions between the cable <NUM> and the terminals <NUM>. The connection portions between the cable <NUM> and the terminals <NUM> are covered by the bending suppression member <NUM>, enabling bending of the substrate <NUM> at these portions to be suppressed.

In the example illustrated in <FIG>, a space formed between the scintillator <NUM> (the protective layer <NUM>) and the bending suppression member <NUM>, and between the substrate <NUM> and the bending suppression member <NUM>, is filled with the filler <NUM>. Moreover, an additional and separate bending suppression member 60A is stacked on a front surface of the bending suppression member <NUM> at a region corresponding to the end portion of the scintillator <NUM>, with a bonding layer 54A interposed therebetween. More specifically, the bending suppression member 60A is provided in a region straddling the end portion (outer edge, edge) of the scintillator <NUM>. The bending suppression member 60A may be configured from the same materials as the bending suppression member <NUM>. As illustrated in <FIG>, the amount of bending of the substrate <NUM> is comparatively large at the end portions of the scintillator <NUM>. Forming a multi-layer structure using the bending suppression members <NUM> and 60A at the region corresponding to the end portion of the scintillator <NUM> enables the effect of suppressing bending of the substrate <NUM> to be enhanced at the end portion of the scintillator <NUM>.

As illustrated in <FIG>, the end portion of the bending suppression member <NUM> may be provided so as to be in a position further outside than the end portion of the substrate <NUM>.

In the example illustrated in <FIG>, the bending suppression member <NUM> is bonded to the protective layer <NUM> through the bonding layer <NUM> at a region corresponding to the central portion 33A of the scintillator <NUM>, and a space corresponding to the slope of the peripheral edge portion 33B of the scintillator <NUM> is formed between the scintillator <NUM> (the protective layer <NUM>) and the bending suppression member <NUM>, and between the substrate <NUM> and the bending suppression member <NUM>, at the region corresponding to the peripheral edge portion 33B of the scintillator <NUM> and also at the region further to the outside thereof.

In the example illustrated in <FIG>, the end portion of the bending suppression member <NUM> is supported by the spacer <NUM>. Namely, one end of the spacer <NUM> is connected to the cable <NUM> provided at the end portion of the substrate <NUM>, and the other end of the spacer <NUM> is connected to the end portion of the bending suppression member <NUM> through a bonding layer <NUM>. By using the spacer <NUM> to support the end portion of the bending suppression member <NUM> that extends so as to form the space between itself and the substrate <NUM>, detachment of the bending suppression member <NUM> can be suppressed. Moreover, the bending suppression effect from the bending suppression member <NUM> can be caused to act as far as the vicinity of the end portion of the substrate <NUM>.

In the example illustrated in <FIG>, the filler <NUM> is filled into the space formed between the scintillator <NUM> (the protective layer <NUM>) and the bending suppression member <NUM>, and between the substrate <NUM> and the bending suppression member <NUM>. In the present exemplary embodiment the connection portions between the cable <NUM> and the terminals <NUM> are covered by the filler <NUM>. By filling the filler <NUM> into the space formed between the scintillator <NUM> (the protective layer <NUM>) and the bending suppression member <NUM> and between the substrate <NUM> and the bending suppression member <NUM> in this manner, the bending suppression member <NUM> and the scintillator <NUM> (the protective layer <NUM>) can be better suppressed from detaching from one another than in the embodiment illustrated in <FIG>. Furthermore, due to the scintillator <NUM> having a structure fixed to the substrate <NUM> by both the bending suppression member <NUM> and the filler <NUM>, the scintillator <NUM> and the substrate <NUM> can be suppressed from detaching from one another. Moreover, since the connection portions between the cable <NUM> and the terminals <NUM> are covered by the filler <NUM>, detachment of the cable <NUM> can be suppressed.

In the example illustrated in <FIG>, the outer peripheral portion of the bending suppression member <NUM> is angled so as to follow the slope of the peripheral edge portion 33B of the scintillator <NUM>. The outer peripheral portion of the bending suppression member <NUM> also covers the portion where the bonding layer <NUM> and the protective layer <NUM> cover the substrate <NUM>, the portion on the substrate at the outside thereof, and the connection portion between the cable <NUM> and the terminals <NUM>. The portions of the bending suppression member <NUM> extending over the substrate <NUM> and over the cable <NUM> are respectively bonded to the substrate <NUM> and the cable <NUM> through the bonding layer <NUM>. By covering the connection portions between the cable <NUM> and the terminals <NUM> with the bending suppression member <NUM>, detachment of the cable <NUM> can be suppressed. Moreover, since the other end of the cable <NUM> is anticipated to be connected to a control board mounted with electronic components, there is a concern regarding comparatively large bending of the substrate <NUM> at the connection portions between the cable <NUM> and the terminals <NUM>. The connection portions between the cable <NUM> and the terminals <NUM> are covered by the bending suppression member <NUM>, enabling bending of the substrate <NUM> at these portions to be suppressed.

In the example illustrated in <FIG>, the filler <NUM> is filled into the space formed between the scintillator <NUM> (the protective layer <NUM>) and the bending suppression member <NUM> and between the substrate <NUM> and the bending suppression member <NUM>. Moreover, an additional and separate bending suppression member 60A is stacked on a front surface of the bending suppression member <NUM> at a region corresponding to the end portion of the scintillator <NUM>, with a bonding layer 54A interposed therebetween. More specifically, the bending suppression member 60A is provided in a region straddling the end portion (outer edge, edge) of the scintillator <NUM>. The bending suppression member 60A may be configured from the same materials as the bending suppression member <NUM>. As illustrated in <FIG>, the amount of bending of the substrate <NUM> is comparatively large at the end portions of the scintillator <NUM>. Forming a multi-layer structure using the bending suppression members <NUM> and 60A at the region corresponding to the end portion of the scintillator <NUM> enables the effect of suppressing bending of the substrate <NUM> to be enhanced at the end portion of the scintillator <NUM>.

In processes to manufacture the radiation detector <NUM>, the flexible substrate <NUM> is stuck to a support body, such as a glass substrate or the like, and then after stacking the scintillator <NUM> onto the substrate <NUM>, the support body is detached from the substrate <NUM>. When this is performed bending occurs in the flexible substrate <NUM>, and there is a concern that the pixels <NUM> formed on the substrate <NUM> might be damaged thereby. By stacking the bending suppression member <NUM> on the scintillator <NUM> as in the embodiments illustrated in the examples of <FIG> prior to detaching the support body from the substrate <NUM>, the bending of the substrate <NUM> that occurs when the support body is being detached from the substrate <NUM> can be suppressed, enabling the risk of damage of the pixels <NUM> to be reduced.

<FIG> are cross-sections illustrating examples of installation embodiments of bending suppression members in cases in which bending suppression members are provided on the second surface S2 side of the substrate <NUM>, this being the opposite side to the first surface S1 that contacts the scintillator <NUM>.

In each of the examples of <FIG>, substantially the entire second surface S2 of the substrate <NUM> is in contact with the bending suppression member <NUM> through the bonding layer <NUM>. Namely, the surface area of the bending suppression member <NUM> is substantially the same as the surface area of the substrate <NUM>. An additional and separate bending suppression member 60A is stacked on the face of the bending suppression member <NUM> that is on the opposite side to the face on the substrate <NUM> side of the bending suppression member <NUM>, with a bonding layer 54A interposed therebetween. The bending suppression member 60A may be configured from the same materials as the bending suppression member <NUM>. In cases in which an irradiation side sampling (ISS) approach is adopted as the imaging method of the radiation detector <NUM>, the bending suppression member 60A is preferably provided only on the outer peripheral portion of the substrate <NUM> in order to keep the surface area of the overlapping portion between the bending suppression member 60A and the pixel region 41A as small as possible. Namely, the bending suppression member 60A may have a ring shape including an opening <NUM> at a portion corresponding to the pixel region 41A, as illustrated in <FIG>. Thus forming a multi-layer structure using the bending suppression members <NUM> and 60A at the outer peripheral portion of the substrate <NUM> enables the rigidity of the outer peripheral portion of the substrate <NUM> that is comparatively susceptible to bending to be reinforced.

In the examples illustrated in <FIG>, the bending suppression member 60A is provided in a region straddling the end portion (outer edge, edge) of the scintillator <NUM>. As illustrated in <FIG>, the amount of bending of the substrate <NUM> is comparatively large at the end portions of the scintillator <NUM>. Forming a multi-layer structure using the bending suppression members <NUM> and 60A at the region corresponding to the end portion of the scintillator <NUM> enables the effect of suppressing bending of the substrate <NUM> to be enhanced at the end portion of the scintillator <NUM>.

In cases in which an irradiation side sampling (ISS) approach is adopted as the imaging method of the radiation detector <NUM>, there is a concern that were a portion of the bending suppression member 60A to overlap with the pixel region 41A as illustrated in <FIG>, depending on the substance employed in the bending suppression member 60A this might have an impact on the images. In cases in which a portion of the bending suppression member 60A overlaps with the pixel region 41A, a plastic is therefore preferably employed for the material of the bending suppression member 60A.

Most preferably an embodiment is adopted in which, as illustrated in <FIG> and <FIG>, the bending suppression member 60A straddles the end portion (outer edge, edge) of the scintillator <NUM> but does not overlap with the pixel region 41A (namely, an embodiment in which an edge of the opening <NUM> of the bending suppression member 60A is disposed at the outside of the pixel region 41A). In the example illustrated in <FIG>, the position of the edge of the opening <NUM> of the bending suppression member 60A is substantially aligned with the position of the end portion of the pixel region 41A. In the example illustrated in <FIG>, the edge of the opening <NUM> of the bending suppression member 60A is disposed between the end portion of the pixel region 41A and the end portion of the scintillator <NUM>.

Moreover, the position of the edge of the opening <NUM> of the bending suppression member 60A may be disposed so as to be substantially aligned with the position of the end portion of the scintillator <NUM> as illustrated in <FIG>, or may be disposed so as to be further outside than the end portion of the scintillator <NUM> as illustrated in <FIG>. In such cases there is no structure present where the bending suppression member 60A straddles the end portion (outer edge, edge) of the scintillator <NUM>, and so there might be a concern regarding a lessening of the effect of suppressing bending of the substrate <NUM> at the end portion of the scintillator <NUM>. However, due to forming a multi-layer structure using the bending suppression members <NUM> and 60A at the outer peripheral portion of the substrate <NUM> where the connection portions between the cable <NUM> and the terminals <NUM> are present, the effect of suppressing bending of the substrate <NUM> at the connection portions between the cable <NUM> and the terminals <NUM> is maintained.

In the example illustrated in <FIG>, the surface area of the bending suppression member <NUM> is larger than the surface area of the substrate <NUM>, and the end portion of the bending suppression member <NUM> is disposed further outside than the end portion of the substrate <NUM>. Adopting such an embodiment enables the radiation detector <NUM> to be fixed to the inside of the case <NUM> by screwing a portion of the bending suppression member <NUM> that juts out from the substrate <NUM> to the case <NUM>, or the like.

Note that although examples are illustrated in <FIG> of embodiments in which the position of the outside end portion of the bending suppression member 60A is substantially aligned with the position of the end portion of the substrate <NUM>, there is no limitation to such embodiments. The outside end portion of the bending suppression member 60A may be disposed further to the outside or inside than the end portion of the substrate <NUM>.

Although examples are illustrated in <FIG> of embodiments in which a multi-layer structure is formed using the bending suppression members <NUM> and 60A at the second surface S2 side of the substrate <NUM>, there is no limitation to such embodiments. For example, in cases in which the bending suppression member <NUM> is provided at the scintillator <NUM> side as in the examples of embodiments illustrated in <FIG>, the bending suppression member 60A may be provided alone at the second surface S2 side of the substrate <NUM> in order to reinforce the outer peripheral portion of the substrate <NUM>.

<FIG> is a plan view illustrating an example of a structure of the bending suppression member <NUM>. A main face of the bending suppression member <NUM> may include plural through holes <NUM>. The size and pitch of the through holes <NUM> is prescribed so as to obtain the desired rigidity of the bending suppression member <NUM>.

Including the plural through holes <NUM> in the bending suppression member <NUM> enables air introduced at the joining face of the bending suppression member <NUM> to the scintillator <NUM> side or the substrate <NUM> side to escape through the through holes <NUM>. This enables air bubbles to be suppressed from being generated at the joining face of the bending suppression member <NUM> to the scintillator <NUM> side or the substrate <NUM> side.

There is a concern that air bubbles might be generated at the joining face if no mechanism is provided to allow air introduced at the joining face of the bending suppression member <NUM> to the scintillator <NUM> side or the substrate <NUM> side to escape. For example, were air bubbles arising at the joining face to expand due to heat during operation of the radiographic imaging device <NUM>, there would be a drop in the cohesion between the bending suppression member <NUM> and the scintillator <NUM> side or the substrate <NUM> side. This would lead to a concern that the bending suppression effect from the bending suppression member <NUM> might not be sufficiently exhibited. By using the bending suppression member <NUM> including the plural through holes <NUM> as illustrated in <FIG>, the generation of air bubbles at the joining face of the bending suppression member <NUM> to the scintillator <NUM> side or the substrate <NUM> side can be suppressed as described above, enabling the cohesion between the bending suppression member <NUM> and the scintillator <NUM> side or the substrate <NUM> side to be maintained. This enables the bending suppression effect of the bending suppression member <NUM> to be maintained.

<FIG> is a perspective view illustrating another example of the structure of the bending suppression member <NUM>. In the example illustrated in <FIG>, the bending suppression member <NUM> includes an indented and protruding structure on the joining face to the scintillator <NUM> side or the substrate <NUM> side. The indented and protruding structure may be configured including plural grooves <NUM> arranged parallel to each other, as illustrated in <FIG>. The face of the bending suppression member <NUM> that includes the indented and protruding structure configured from the plural grooves <NUM> is, for example as illustrated in <FIG>, joined to the scintillator <NUM> that has been covered by the reflective film <NUM>. In this manner, due to the bending suppression member <NUM> including the indented and protruding structure on the joining face to the scintillator <NUM> side or the substrate <NUM> side, any air introduced to the joining portion of the bending suppression member <NUM> and the scintillator <NUM> side or the substrate <NUM> side is able to escape through the grooves <NUM>. Similarly to in the embodiment illustrated in <FIG>, this accordingly enables the generation of air bubbles at the joining face of the bending suppression member <NUM> to the scintillator <NUM> side or the substrate <NUM> side to be suppressed. This enables the cohesion between the bending suppression member <NUM> and the scintillator <NUM> side or the substrate <NUM> side to be maintained, and enables the bending suppression effect of the bending suppression member <NUM> to be maintained.

<FIG> are plan views illustrating other example of structures of the bending suppression member <NUM>. As illustrated in <FIG>, the bending suppression member <NUM> may be segmented into plural pieces <NUM>. The bending suppression member <NUM> may, as illustrated in <FIG>, be segmented into the plural pieces <NUM> arrayed along one direction. Moreover, the bending suppression member <NUM> may, as illustrated in <FIG>, be segmented into the plural pieces <NUM> arrayed in both a longitudinal direction and a lateral direction.

The greater the surface area of the bending suppression member <NUM>, the more readily air bubbles are generated at the joining face of the bending suppression member <NUM> to the scintillator <NUM> side or the substrate <NUM> side. As illustrated in <FIG>, segmenting the bending suppression member <NUM> into the plural pieces <NUM> enables air bubbles to be suppressed from being generated at the joining face of the bending suppression member <NUM> to the scintillator <NUM> side or the substrate <NUM> side. This enables the cohesion between the bending suppression member <NUM> and the scintillator <NUM> side or the substrate <NUM> side to be maintained, and thereby enables the bending suppression effect of the bending suppression member <NUM> to be maintained.

<FIG> are diagrams respectively illustrating other configuration examples of the radiographic imaging device <NUM>. The radiographic imaging device <NUM> is configured including the case <NUM>, the radiation detector <NUM> housed inside the case <NUM>, and a control board <NUM> and a power source <NUM>.

The control board <NUM> is a board mounted with some or all of the electronic components configuring the controller <NUM>, the image memory <NUM>, the gate line driver <NUM>, the charging amplifiers <NUM>, and the signal processor <NUM> illustrated in <FIG>. The control board <NUM> may be a rigid board having a higher rigidity than that of the flexible substrate <NUM>. The power source <NUM> supplies power through power lines <NUM> to the electronic components mounted on the control board <NUM>.

The case <NUM> is preferably lightweight, has a low absorption ratio to X-rays, and has high rigidity, and is preferably configured from a material that has an elastic modulus sufficiently higher than that of the bending suppression member <NUM>. A material having a bending elastic modulus of at least <NUM> MPa is preferably employed as the material of the case <NUM>. Examples of materials suitably employed as the material of the case <NUM> include carbon or carbon fiber reinforced plastics (CFRP) having a bending elastic modulus of around <NUM>,<NUM> MPa to <NUM>,<NUM> MPa.

When radiographic images are imaged using the radiographic imaging device <NUM>, load is applied to the radiation-incident face <NUM> of the case <NUM> by the imaging subject. In cases in which the bending suppression member <NUM> is, for example, configured from a material having a comparatively low elastic modulus, such as a soft plastic or the like, then there is a concern that were the rigidity of the case <NUM> to be insufficient, then bending might occur in the substrate <NUM> under the load from the imaging subject, resulting in problems such as damage to the pixels <NUM>. By housing the radiation detector <NUM> equipped with the bending suppression member <NUM> inside the case <NUM> made from a material having a bending elastic modulus of not less than <NUM>,<NUM> MPa, bending of the substrate <NUM> under load from the imaging subject can be suppressed, even in cases in which the bending suppression member <NUM> is configured from a material having a comparatively low elastic modulus, such as a soft plastic or the like. By causing the bending suppression member <NUM> and an inner wall face of the case <NUM> to cohere, the effect of suppressing bending of the substrate <NUM> under the load from the imaging subject can be further enhanced. In such cases, the bending suppression member <NUM> and the inner wall face of the case <NUM> may be bonded through a bonding layer, or may simply be placed in contact with each other without interposing a bonding layer.

The examples illustrated in <FIG> are examples of configurations in which the radiation detector <NUM>, the control board <NUM>, and the power source <NUM> are arranged next to each other along a lateral direction in the drawings. As illustrated in <FIG>, in the internal space of the case <NUM>, the thickness of a region housing the radiation detector <NUM> may be made thinner than the thickness of a region housing the control board <NUM> and the power source <NUM>. Adopting this approach enables configuration of an ultra-thin portable electronic cassette having a thickness appropriate to the thickness of the radiation detector <NUM>. In order to soften a step formed between the region housing the radiation detector <NUM> and the region housing the control board <NUM> and the power source <NUM>, the case <NUM> preferably includes a sloping portion 14A at a portion where these two regions are connected together. By including the sloping portion 14A in the case <NUM>, any discomfort felt by a patient serving as the imaging subject can be reduced when the radiographic imaging device <NUM> is employed in a state inserted below the patient.

Claim 1:
A radiation detector comprising:
a flexible substrate (<NUM>);
a plurality of pixels (<NUM>) provided on the substrate (<NUM>) and each including a photoelectric conversion element (<NUM>);
a scintillator (<NUM>) stacked on the substrate (<NUM>) and including a plurality of columnar crystals (32a); and
a bending suppression member (<NUM>) configured to suppress bending of the substrate (<NUM>), wherein the bending suppression member (<NUM>) has a bending elastic modulus of from <NUM> MPa to <NUM> MPa; and
characterized by further comprising
reinforcement members (<NUM>) provided in a region straddling boundaries between the region where the scintillator (<NUM>) is present and regions where the scintillator (<NUM>) is not present and on an opposite side to a side of the substrate (<NUM>) at which the scintillator (<NUM>) is provided so as to reinforce a bending suppression effect of the bending suppression member (<NUM>).