Radiation image detector

Abstract

The present invention provides a radiation image detector equipped with a scintillator panel that enables the formation of a large deposition area film layer while reducing the formation cost and achieving uniform brightness distribution in the scintillator panel. [Solution] The radiation image detector 1 comprises a scintillator panel 2 having a substrate 10 and a vapor-deposited film layer 20 on the substrate surface 10a of the substrate 10, in which a phosphor component is deposited in a film form together with an activator component. The vapor-deposited film thickness T, which corresponds to the thickness of the vapor-deposited film layer 20 from the substrate surface 10a, is set to a thickness within ±10% of the median film thickness across the entire layer of the vapor-deposited film layer 20. The film thickness distribution related to the vapor-deposited film thickness T and the activator concentration distribution related to the activator concentration of the activator component in the vapor-deposited film layer 20 are correlated.

Description

Technical Field

[0001] The present disclosure relates to a radiation image detector. Background Art

[0002] Conventionally, a radiation image detector (FPD: Flat Panel Detector) using a radiation detection section is known, which converts incident radiation into light such as visible light by a scintillator panel, and detects the converted light with a plurality of photoelectric conversion elements such as photodiodes two-dimensionally arranged on a substrate. The radiation image detector further converts light incident on the photoelectric conversion elements into electric charges, and extracts the generated electric charges, thereby detecting information carried by radiation irradiated through a subject as an electric signal. Radiation images obtained by this principle are used in various industrial fields including the medical field.

[0003] In the radiation detection section described above, the scintillator panel mainly includes a substrate and a scintillator that is a vapor-deposited film layer (phosphor film layer) formed by growing a phosphor component as columnar crystals on one substrate surface of the substrate. For the phosphor component, for example, cesium iodide, gadolinium sulfide or the like, which serves as a base material of the scintillator, is used, and an activator for the scintillator such as thallium is contained. Scintillator panels having scintillators such as thallium-activated cesium iodide (CsI:Tl) and sodium-activated cesium iodide (CsI:Na) obtained by vapor-depositing the base material and activator of these scintillators on a substrate surface by a vapor phase growth method are known (see Patent Documents 1 to 3, etc.). A scintillator is a substance that absorbs radiation such as X-rays and emits light, and is mainly used in radiation detectors. When radiation strikes the scintillator, it has the function of converting the energy of the radiation into light.

[0004] In the scintillator panel of a radiation detection unit, the thickness of the vapor-deposited film layer is known to significantly contribute to the luminance, which is the brightness per unit area of ​​light converted by the scintillator panel. Therefore, in forming the vapor-deposited film layer of the scintillator panel, it is necessary to precisely control the deposition conditions of phosphor components such as cesium iodide to form a vapor-deposited film layer with a uniform film thickness distribution without bias. [Prior art documents] [Patent Documents]

[0005] [Patent Document 1] Japanese Patent Publication No. 2004-63272 [Patent Document 2] Japanese Patent Publication No. 2021-94076 [Patent Document 3] Japanese Patent Publication No. 2018-9803 [Overview of the project] [Problems that the invention aims to solve]

[0006] However, as mentioned above, vapor deposition is primarily carried out using the vapor phase growth method, which requires gradually growing crystals on the substrate surface from a vaporization source containing phosphor components. Therefore, there was a possibility of unevenness in the film thickness distribution of the vapor deposition layer. In particular, when attempting to form a vapor deposition layer with a large deposition area using the vapor phase growth method (for example, a size of 500 mm x 500 mm or larger), there was a possibility of significant unevenness in the film thickness distribution. As a result, there was a possibility that the brightness distribution of the scintillator panel (vapor deposition layer) would not be uniform.

[0007] Conventionally, many attempts and methods have been proposed to form vapor-deposited film layers with a uniform film thickness distribution using vapor phase growth. For example, a vapor deposition method is used in which phosphor components are vaporized from an evaporation source placed on the substrate side while the substrate to be deposited is rotated at a predetermined rotation speed. Furthermore, methods are known in which multiple evaporation sources are arranged at predetermined intervals to control the amount of phosphor components deposited on the substrate surface, or in which the distance between the substrate surface and the evaporation source is increased to average the amount of phosphor components deposited on the substrate surface.

[0008] However, the above deposition method sometimes required complex control to form a deposited film with a uniform film thickness distribution. Furthermore, using multiple evaporation sources or increasing the distance between the substrate and the evaporation sources could potentially increase the amount of phosphor components, such as cesium iodide, used as raw materials. In particular, increasing the distance between the substrate surface and the evaporation source meant that only a portion of the phosphor components vaporized and evaporated from the evaporation source were deposited on the substrate surface, potentially wasting the remaining phosphor components that were not used for deposition. As a result, the utilization rate of the phosphor components decreased, potentially increasing the raw material costs in forming the deposited film layer.

[0009] Therefore, in view of the above circumstances, this disclosure aims to provide a radiation image detector equipped with a scintillator panel that can uniformize the brightness distribution in the scintillator panel, and in particular reduce the formation cost, while enabling the formation of a vapor-deposited film layer having a large deposition area. [Means for solving the problem]

[0010] To solve the above problem, the radiation image detector described in claim 1 is: circuit board and A vapor-deposited film layer is formed on the substrate surface of the aforementioned substrate by depositing a phosphor component together with an activator component in a film-like manner, Equipped with a scintillator panel having, The deposition film thickness corresponding to the thickness of the deposition film layer from the substrate surface is, The thickness of the aforementioned deposited film layer is set to be within ±10% of the median film thickness across the entire layer. The film thickness distribution related to the deposition film thickness and the activator concentration distribution related to the activator concentration of the activator component in the deposition film layer are correlated.

[0011] The invention described in claim 2 is a radiation image detector according to claim 1, The correlation between the film thickness distribution and the activator concentration distribution is, If the deposition film thickness in a specific region of the deposition film layer is thicker than the reference film thickness value, the activator concentration in the specific region is set lower than the reference concentration value. If the deposition film thickness in the specified region is thinner than the reference film thickness value, the activator concentration in the specified region is set higher than the reference concentration value.

[0012] The invention described in claim 3 is a radiation image detector according to claim 1, The aforementioned phosphor component is Cesium iodide was used, The aforementioned activating agent component is Thallium is used.

[0013] The invention described in claim 4 is a radiation image detector described in claim 2, The aforementioned reference film thickness value is, Using the median film thickness, The aforementioned reference concentration value is, The median concentration of the activator across the entire layer of the vapor-deposited film layer is used.

[0014] The invention described in claim 5 is a radiation image detector according to claim 1, The median thickness of the aforementioned vapor-deposited film layer is, The size is 150-800 μm. The concentration of the activator in the vapor-deposited film layer is It is 0.1 to 1.5 mol%, The brightness of the scintillator panel having the aforementioned vapor-deposited film layer is The brightness is within ±5% of the median brightness across the entire layer of the aforementioned deposited film layer.

[0015] The invention according to claim 6 is the radiation image detector according to claim 1, the film thickness distribution is at least one of a concentric circular shape, a concentric semicircular shape, and a concentric quarter-circular shape, and the activator concentration distribution corresponds to the film thickness distribution.

[0016] The invention according to claim 7 is the radiation image detector according to claim 1, the vapor-deposited film layer comprises: a first vapor-deposited film layer in which the thickness of the vapor-deposited film from the substrate surface is within 10% of the maximum film thickness from the substrate surface; and a second vapor-deposited film layer laminated on the first vapor-deposited film layer, wherein the thickness of the vapor-deposited film from the first vapor-deposited film layer ranges from more than 10% to the maximum film thickness; and wherein the first vapor-deposited film layer does not contain the activator component.

[0017] The invention according to claim 8 is the radiation image detector according to claim 1, the vapor-deposited film layer comprises: a third vapor-deposited film layer in which the thickness of the vapor-deposited film from the substrate surface is within 50% of the maximum film thickness from the substrate surface; and a fourth vapor-deposited film layer laminated on the third vapor-deposited film layer, wherein the thickness of the vapor-deposited film from the third vapor-deposited film layer ranges from more than 50% to the maximum film thickness; and wherein at least 70% or more of the activator component based on the total amount of the activator component contained in the vapor-deposited film layer is contained in the third vapor-deposited film layer. Effects of the Invention

[0018] According to the present disclosure, a radiation image detector including a scintillator panel with a uniform luminance distribution can be provided. Brief Description of the Drawings

[0019] [Figure 1]This is an explanatory diagram showing the schematic configuration of the radiation image detector of this embodiment. [Figure 2] This is a schematic diagram illustrating the vapor deposition process involved in the formation of a vapor-deposited film layer. [Figure 3] This is an explanatory diagram schematically showing the deposition film thickness, activator concentration, and brightness at each position in the deposited film layer of Figure 2. [Figure 4] This is an explanatory diagram schematically showing the film thickness distribution, activator concentration distribution, and brightness distribution of the vapor-deposited film layer. [Figure 5] This is an explanatory diagram showing a concentric semicircular film thickness distribution. [Figure 6] This is an explanatory diagram showing a concentric, quadrilateral-shaped film thickness distribution. [Figure 7] This is a schematic diagram illustrating an alternative configuration of a vapor-deposited film layer having a first vapor-deposited film layer and a second vapor-deposited film layer. [Figure 8] This is a schematic diagram illustrating an alternative configuration of a vapor-deposited film layer having a third vapor-deposited film layer and a fourth vapor-deposited film layer. [Figure 9] This is a schematic diagram illustrating the vapor deposition process for the formation of the vapor-deposited film layer in the comparative example. [Figure 10] This is an explanatory diagram schematically showing the deposition film thickness, activator concentration, and brightness at each position in the deposited film layer of Figure 9. [Modes for carrying out the invention]

[0020] The embodiments of the radiation image detector in this disclosure will be described below with reference to the drawings. However, the scope of this disclosure is not limited to the following illustrated examples. Furthermore, the figures do not necessarily faithfully represent the dimensional ratios of the actual components. In addition, in this specification, "phosphor" refers to all substances that convert energy such as radiation from the outside into light, and in a broad sense includes "scintillators". Furthermore, "cesium iodide" is the base material of the scintillator, while "thallium" is the activator of the scintillator.

[0021] [1. Configuration of the radiation image detector] A radiation image detector 1 according to one embodiment of the present disclosure comprises a scintillator panel 2 and other components. The scintillator panel 2 has the function of converting incident radiation R into light P of a different wavelength and emitting it to generate a radiation image corresponding to the radiation R.

[0022] For example, as shown in Figure 1, when radiation R in the X-ray wavelength range is incident on the scintillator panel 2, it is converted into light P, a type of electromagnetic wave with wavelengths in the range of 300 nm to 800 nm, which includes the visible light region and partly the ultraviolet wavelength region and the infrared wavelength region.

[0023] The radiation image detector 1 also includes a housing 3 and a radiation detection unit housed inside the housing 3, with a scintillator panel 2 as one component of the radiation detection unit. The radiation detection unit also includes, for example, an element substrate on which a photoelectric conversion element is mounted, and the element substrate and the scintillator panel 2 are bonded together via an adhesive layer or the like. The element substrate has the function of detecting the light P converted by the scintillator panel 2 using the photoelectric conversion element on the element substrate and converting it into an electric charge.

[0024] This allows for obtaining radiation images based on radiation R. Detailed explanations and illustrations of other configurations related to the radiation image detector 1 and radiation detection unit, as well as the applications of the radiation image detector 1, are omitted.

[0025] [2. Scintillator Panel Configuration] The scintillator panel 2 in the radiation image detector 1 of this embodiment mainly comprises a substrate 10 and a vapor-deposited film layer 20 formed in a film-like manner on one substrate surface 10a of the substrate 10, as schematically shown in Figure 1, etc.

[0026] In this embodiment, the vapor-deposited film layer 20 is shown to be placed on the substrate surface 10a, which corresponds to the back side of the substrate 10 (the lower side of the paper in Figure 1), but the embodiment is not limited to this. In this embodiment, an incident surface 10b is further provided on the surface of the substrate 10 that is opposite to the substrate surface 10a and corresponds to the front side of the substrate 10 (the upper side of the paper in Figure 1), to which radiation R is incident.

[0027] The radiation R is irradiated from the incident surface 10b side, and the scintillator panel 2 receives the radiation R on the incident surface 10b side, and also emits light P, which includes the visible light region and the like, from the vapor-deposited film layer 20 side, after passing through the substrate 10 and the vapor-deposited film layer 20 and being converted during the process of passing through the vapor-deposited film layer 20.

[0028] In the illustrated Figures 1, 3, 5, 7, and 8, unless otherwise specified, the incident direction of radiation R and the exit direction of light P from the scintillator panel 2 are assumed to be the same. Therefore, in Figure 1, etc., radiation R is incident from the top of the page toward the bottom of the page, and light P is emitted.

[0029] The material constituting the substrate 10 is not particularly limited. For example, the substrate 10 may be a glass substrate formed using an inorganic material glass. Alternatively, the substrate 10 may be a polymer material substrate formed using an organic polymer material such as cellulose acetate film, polyester film, polyethylene terephthalate film, or polyimide (PI) film.

[0030] The shape of the substrate 10 is not particularly limited and can be designed appropriately according to the shape of the FPD used. For example, the substrate 10 may be a roughly rectangular flat plate.

[0031] The thickness of the substrate 10 (corresponding to the vertical direction in Figure 1) is not particularly limited. It can be appropriately selected depending on the transmittance of radiation R such as X-rays and the detection size of radiation R in the radiation image detector 1. For example, it is preferable that the substrate thickness of the substrate 10 be 600 μm or less. Furthermore, in order to make the deposition film thickness T of the deposition film layer 20, which will be described later, as uniform as possible, it is preferable that the substrate surface 10a (and incident surface 10b) of the substrate 10 is also formed as a smooth surface with few irregularities.

[0032] In this embodiment, the vapor-deposited film layer 20 of the scintillator panel 2 is formed by depositing a phosphor component 22 in a film-like manner on the substrate surface 10a side of the substrate 10. Here, in Figure 1, for the sake of simplicity, the vapor-deposited film layer 20 is shown as having a constant vapor-deposited film thickness T from the substrate surface 10a, but this is a schematic representation, and in reality, the vapor-deposited film layer 20 has minute irregularities of about several tens of micrometers.

[0033] [3. Evaporation image related to the formation of the vapor-deposited film layer] The vapor-deposited film layer 20 can be manufactured, for example, in a vacuum chamber using a manufacturing apparatus as shown in the vapor deposition image in Figure 2. Specifically, a support substrate 21 that rotates in a predetermined rotation direction Y according to a rotation axis X is used, and while the substrate 10 fixed to the support substrate 21 is rotated, vapor deposition is carried out using a vapor phase growth method such as vacuum deposition or sputtering. In this way, the vapor-deposited film layer 20 is formed on the substrate surface 10a of the substrate 10 while the phosphor component 22 is grown in a vacuum atmosphere.

[0034] To explain in more detail, as shown in Figure 2, the formation of the vapor-deposited film layer 20 begins by fixing the substrate 10 to be vapor-deposited onto the support substrate 21 with the substrate surface 10a facing downwards. As a result, the substrate 10 rotates along with the support substrate 21 according to the rotation axis X.

[0035] A first phosphor evaporation source 23a for vaporizing and evaporating the phosphor component 22 is positioned on the axial extension of the central deposition position a0, which is spaced downward from the substrate surface 10a of the substrate 10 and coincides with the rotation axis X direction, which is the rotation center of the substrate 10. In this embodiment, cesium iodide (CsI), which is the base material of the scintillator, is used as the phosphor component 22, which is the raw material (deposition material) for forming the deposition film layer 20. A first activator evaporation source 25a for vaporizing and evaporating the activator component 24 is positioned on the axial extension of the third deposition position a3, which is spaced radially outward from the central deposition position a0, which corresponds to the rotation center (corresponding to the left direction in Figure 2). In this embodiment, thallium (Tl) is used as the activator component 24, which is added to the phosphor component 22 and included in the deposition film layer 20.

[0036] As described above, cesium iodide can generally be used as the base material for the scintillator constituting the vapor-deposited film layer 20. This cesium iodide has the property of efficiently converting radiation into light. Furthermore, an activator component 24 may be added to improve the performance of the scintillator. For example, as mentioned above, by adding a small amount of thallium (Tl) to the cesium iodide, which is the base material of the scintillator, it is possible to improve the luminescence efficiency of the scintillator.

[0037] The second phosphor evaporation source 23b and the second activator evaporation source 25b are alternately arranged on the axial extension lines opposite to the second evaporation position a2 and the first evaporation position a1, which are further radially separated from the third evaporation position a3. As a result, the four sources—the first phosphor evaporation source 23a, the first activator evaporation source 25a, the second phosphor evaporation source 23b, and the second activator evaporation source 25b—are alternately arranged at equal intervals along the radially outward direction from the central evaporation position a0, which is the rotation center of the substrate 10.

[0038] The arrangement order of each evaporation source 23a, etc., is not limited to this; for example, the first activator evaporation source 25a may be located on the axial extension line relative to the central deposition position a0. Furthermore, the number of evaporation sources 23a, etc., is not limited to this; four or more evaporation sources may be provided.

[0039] As shown in Figure 2, multiple evaporation sources 23a, etc., are arranged at positions opposite the substrate surface 10a. Here, the evaporation source-substrate distance L between each evaporation source 23a, etc. and the substrate surface 10a can be, for example, in the range of 200 mm to 1000 mm. If the evaporation source-substrate distance L is large, in other words, if the evaporation sources 23a, etc. are far from the substrate surface 10a, the utilization efficiency of the phosphor component 22, which is the raw material, decreases. Therefore, it is expected that the formation cost will increase. On the other hand, if the evaporation source-substrate distance L is small, in other words, if the evaporation sources 23a and the substrate surface 10a are close, a bias is likely to occur in the film thickness distribution 30 (see Figure 4) related to the deposited film thickness T.

[0040] In this embodiment, the distance L between the evaporation source and the substrate can be set to a shorter distance. That is, it becomes possible to improve the utilization efficiency of the phosphor component 22 and to form the evaporated film layer 20 under conditions that allow for a certain degree of film thickness distribution 30.

[0041] The support substrate 21 and the substrate 10 fixed to the support substrate 21 are rotated at a constant rotational speed in the rotational direction Y along the rotation axis X. The rotational speed of the support substrate 21, etc., along the rotation axis X is not particularly limited and can be set to conditions typically used to form a vapor-deposited film layer 20, for example, around 1 to 15 rpm.

[0042] As the substrate 10 rotates along its axis, the relative positions of the second phosphor evaporation source 23b, the first activator evaporation source 25a, and the second activator evaporation source 25b, and a specific point (or range) on the substrate surface 10a of the substrate 10 change moment by moment. Here, since the central deposition position a0 on the substrate surface 10a is the center of rotation, the distance between the first phosphor evaporation source 23a, which is located on the axial extension of the central deposition position a0, and the substrate surface 10a remains constant at the set evaporation source-substrate distance L, and no change occurs in the relative positional relationship.

[0043] Next, the deposition film layer 20 is formed by rotating the substrate 10 together with the support substrate 21, and vaporizing and evaporating the phosphor component 22 or the activator component 24 from the first phosphor evaporation source 23a, the second phosphor evaporation source 23b, the first activator evaporation source 25a, and the second activator evaporation source 25b, respectively. Details of the configuration of each evaporation source 23a, etc., and the deposition method are conventionally well known, so a detailed explanation is omitted here. In this embodiment, the deposition image shown in Figure 2 is carried out under vacuum.

[0044] The phosphor components 22 vaporize under vacuum from each evaporation source 23a, etc., and evaporate, moving upward (corresponding to the top of the paper in Figure 2), reaching the substrate surface 10a of the substrate 10, which is positioned opposite to the upper side of each evaporation source 23a, etc. Then, they are deposited onto the substrate surface 10a, and crystal growth occurs from the substrate surface 10a, forming a film-like deposited film layer 20 that covers, for example, the entire roughly rectangular substrate surface 10a.

[0045] The vapor-deposited film thickness T, which corresponds to the thickness from the substrate surface 10a, can be appropriately adjusted by vapor deposition conditions such as the pre-set vapor deposition time and the amount of phosphor component 22 vaporized from the first phosphor evaporation source 23a and the second phosphor evaporation source 23b.

[0046] The vapor-deposited film thickness T may be, for example, 500 μm or less. If the vapor-deposited film thickness T exceeds 500 μm, the vapor deposition time required to form the vapor-deposited film layer 20 will be longer, and a larger amount of phosphor component 22 will need to be evaporated. As a result, there is a possibility that a large amount of phosphor component 22 will not be used for vapor deposition, which is expected to reduce the utilization efficiency of the phosphor component 22 and increase the cost of forming the vapor-deposited film layer 20.

[0047] As already explained, the luminance B (see Figure 3, etc.), which corresponds to the brightness per unit area of ​​light P, is greatly influenced by the deposition film thickness T of the deposition film layer 20. However, in the vapor phase growth method shown in Figure 2, it is not easy to form a uniform deposition film thickness T across the entire layer of the deposition film layer 20. In particular, when forming a deposition film layer 20 with a particularly large deposition area, there is a possibility that the deposition film thickness T (film thickness distribution 30) will be significantly uneven.

[0048] In the radiation image detector 1 of this embodiment, the vapor deposition film thickness T (film thickness distribution 30) of the vapor deposition film layer 20 constituting the scintillator panel 2 is characterized in that a certain degree of bias is permissible. That is, the median value of the vapor deposition film thickness T across the entire layer of the vapor deposition film layer 20 is calculated, and the vapor deposition film thickness T is acceptable as long as it is within ±10% of the calculated median value.

[0049] <Measurement of vapor deposition film thickness> The deposition film thickness T of the deposited film layer 20 was measured using an overcurrent film thickness gauge (ISOSCOPE MP10E: manufactured by Fischer Instruments Co., Ltd.). A grid consisting of equally spaced lines in the vertical and horizontal directions was placed on the deposited film layer 20, and the deposition film thickness T was measured at least nine points, with the intersections serving as measurement points. Based on the obtained measurement results, the median film thickness was calculated.

[0050] For example, if the median thickness T of the obtained vapor-deposited film layer 20 is 400 μm, the vapor-deposited film thickness T in the vapor-deposited film layer 20 can range from a minimum of 360 μm to a maximum of 440 μm. In other words, in this embodiment, the vapor-deposited film layer 20 has a tolerance of ±40 μm from the median thickness. This allows for more relaxed formation conditions (vapor deposition conditions) compared to the formation of vapor-deposited film layers in conventional scintillator panels. As a result, the production of the vapor-deposited film layer 20 becomes easier, and the possibility of reducing the utilization efficiency of the phosphor component 22 is reduced. In other words, the formation cost of the vapor-deposited film layer 20 is not increased.

[0051] The vapor-deposited film layer 20 formed in the above vapor deposition image may have a large variation in the vapor-deposited film thickness T across the entire layer, in other words, a large bias in the film thickness distribution 30.

[0052] To explain in more detail, according to the deposition image for the formation of the deposited film layer 20 shown in Figure 2, the first phosphor evaporation source 23a is positioned at the central deposition position a0 of the substrate surface 10a of the substrate 10, which is located on the axial extension of the rotation axis X.

[0053] In this case, the phosphor component 22 that vaporizes and evaporates from the first phosphor evaporation source 23a is most likely to be deposited near the central deposition position a0 of the substrate surface 10a, which is closest to the first phosphor evaporation source 23a. Although the substrate 10 itself rotates, the central deposition position a0 is the center of rotation, and its relative position to the first phosphor evaporation source 23a hardly changes.

[0054] As a result, the amount of phosphor component 22 deposited is greatest at the central deposition position a0. Therefore, the deposition film thickness T is thicker. On the other hand, the amount of deposition gradually decreases as you move away from the central deposition position a0. Therefore, the deposition film thickness T is thinner compared to the central deposition position a0 (see Figure 3).

[0055] Furthermore, as shown in the deposition image in Figure 2, the second phosphor evaporation source 23b is positioned opposite the second deposition location a2, which is radially separated from the central deposition location a0. As a result, the amount of phosphor component 22 vaporized and evaporated from the second phosphor evaporation source 23b is increased on the substrate surface 10a at the second deposition location a2, which is closest to the second phosphor evaporation source 23b.

[0056] Since the substrate 10 rotates along the rotation axis X, the second deposition position a2 on the substrate surface 10a changes moment by moment. As a result, concentric areas with thicker deposition film T are formed at the location corresponding to the second deposition position a2, centered on the central deposition position a0.

[0057] In a virtual cross-sectional view of the vapor-deposited film layer 20 from the side (from the front of the paper to the depth of the paper in Figure 2), the vapor-deposited film thickness T is thickest at the central deposition position a0, the second deposition position a2, and the reverse second deposition position a2' on the opposite side of the second deposition position a2, with the central deposition position a0 in between (see Figure 3). That is, as shown in the virtual cross-sectional view of Figure 3, the vapor-deposited film thickness T in the vapor-deposited film layer 20 changes in a wave-like pattern.

[0058] In contrast, in the deposition image shown in Figure 2, the first activator evaporation source 25a and the second activator evaporation source 25b are positioned opposite the first deposition position a1 and the third deposition position a3 on the substrate 10, respectively. Therefore, the activator concentration C is such that a large amount of activator component 24 is deposited at the first deposition position a1 and the third deposition position a3, where the first activator evaporation source 25a and the second activator evaporation source 25b are closest to the substrate surface 10a.

[0059] In other words, in a virtual cross-sectional view of the vapor-deposited film layer 20 from the side, the activator concentration C is thickest at the inverse first vapor deposition position a1' and inverse third vapor deposition position a3', which are on the opposite side of the first vapor deposition position a1 and third vapor deposition position a3, with the first vapor deposition position a1 and third vapor deposition position a3 in between (see Figure 3). That is, as shown in the virtual cross-sectional view of Figure 3, in the formed vapor-deposited film layer 20, the activator concentration C in the vapor-deposited film layer 20 changes in a wave-like pattern that is approximately in opposite phase to the vapor-deposited film thickness T.

[0060] <Measurement of activator concentration> The activator concentration of the activator component 24 contained in the vapor-deposited film layer 20 was determined as follows. Centered around the measurement point where the vapor-deposited film thickness T was measured, the vapor-deposited film (phosphor) was cut out from the vapor-deposited film layer 20, and the vapor-deposited film was pulverized to measure the activator concentration. The activator concentration of the cut-out vapor-deposited film was measured using ICP emission spectrometry (ICP-OES: Inductively-Coupled-Plasma Optical Emission Spectrometry), X-ray fluorescence analysis, etc. When using ICP emission spectrometry, concentrated hydrochloric acid was added to the vapor-deposited film and heated to dryness, then aqua regia was added and heated to dissolve it, and then the sample was appropriately diluted with ultrapure water and set as a measurement sample in an ICP emission spectrometer (SPS3100: manufactured by Seiko Instruments Inc.) for measurement.

[0061] Furthermore, when measuring the activator concentration in the X-ray irradiated half of the film thickness, the vapor-deposited film was cut from the X-ray irradiated side until half the film thickness was achieved, and the activator concentration was measured using the obtained sample in the same manner as above. In this case, the film may be cut from the opposite side of the X-ray irradiated side until half the film thickness is achieved, and the remaining portion may be cut further. Also, if the vapor-deposited film is brittle and difficult to cut, the vapor-deposited film may be filled with resin before cutting.

[0062] The activator component 24 is added in trace amounts to the phosphor component 22, and the amount of activator component 24 (activator concentration C) does not affect the vapor deposition film thickness T.

[0063] As described above, in this embodiment, the vapor-deposited film layer 20 of the scintillator panel 2 shows a correlation between the vapor-deposited film thickness T of the vapor-deposited film layer 20 and the activator concentration C of the activator component 23 in a virtual cross-sectional view. Furthermore, when this is replaced on a plane, the film thickness distribution 30 of the vapor-deposited film layer 20 and the activator concentration distribution 40 are correlated with each other.

[0064] On the other hand, the luminance B, which corresponds to the brightness per unit area of ​​light P generated by the conversion of radiation R by the scintillator panel 2, is greatly influenced by the deposition film thickness T of the deposition film layer 20. For example, in the film thickness distribution 30 shown in Figure 4, the luminance of the thick film region 31 is higher in areas where the deposition film thickness T is thick (thick film region 31). Conversely, the luminance of the thin film region 32 is lower in areas where the deposition film thickness T is thin (thin film region 32).

[0065] Furthermore, the brightness B in the scintillator panel 2 is also affected by the activator concentration C of the activator component 24 contained in the vapor-deposited film layer 20. For example, in the activator concentration distribution 40 shown in Figure 4, in areas with a high activator concentration C (high concentration areas 42), the brightness B in those high concentration areas 42 will be high (brighter). On the other hand, in areas with a low activator concentration C (low concentration areas 41), the brightness B in those low concentration areas 41 will be low (darker).

[0066] In Figure 4, the film thickness distribution 30 and the activator concentration distribution 40 are schematically shown for the deposited film layer 20 formed by the deposition image in Figure 2. Furthermore, in Figure 4, in the film thickness distribution 30, the thick film region 31, which corresponds to the region where the deposited film thickness T is thick (large), is shown with dark hatching, and the thin film region 32, which corresponds to the region where the deposited film thickness T is thin (small), is shown with light hatching. On the other hand, in the activator concentration distribution 40, the low concentration region 41, which corresponds to the region where the activator concentration C is low (thin), is shown with light hatching, and the high concentration region 42, which corresponds to the region where the activator concentration C is high (dense), is shown with dark hatching.

[0067] In this embodiment, the scintillator panel 2 allows the vapor-deposited film thickness T of the vapor-deposited film layer 20 to be within a range of 10% or less of the median film thickness. In addition, focusing on the activator concentration C and activator concentration distribution 40 of the activator component 24 in the vapor-deposited film layer 20, which affect the brightness B of the converted light P, the film thickness distribution 30 related to the vapor-deposited film thickness T and the activator concentration distribution 40 related to the activator concentration C are correlated. As a result, the brightness distribution 50 related to the brightness B of the final converted light P becomes uniform across the entire layer of the vapor-deposited film layer 20 (see Figures 3 and 4).

[0068] <Brightness Measurement> Brightness was measured by irradiating a radiation image detector equipped with a scintillator panel with X-rays at a voltage of 80 kVp, and using the signal values ​​of the pixels acquired by the radiation image detector. The median brightness of the FPD was defined as the median brightness of the radiation image detector, which is the median signal of the pixels present in the entire effective image area.

[0069] In other words, the two conditions (parameters) of the vapor-deposited film layer 20, the vapor-deposited film thickness T and the activator concentration C, are in a so-called "trade-off" relationship. As a result, even if one condition results in low brightness (darkness), the other condition results in high brightness (brightness). This makes it possible to form the vapor-deposited film layer 20 without making the film formation conditions for the vapor-deposited film layer 20, in particular the condition for uniformity of the vapor-deposited film thickness T, and by adjusting with the activator concentration C, uniformity of the brightness B of the final light P can be achieved across the entire layer.

[0070] The details of the correlation between the film thickness distribution 30 and the activator concentration distribution 40 are described below. In the film thickness distribution 30 of the deposited film layer 20, in the thick film region 31 where the deposited film thickness T is thicker than a predetermined reference film thickness value, the activator concentration C in the region of the activator concentration distribution 40 corresponding to the thick film region 31 (low concentration region 41) is set lower than a predetermined reference concentration value. As a result, the two characteristics of the thick film region 31 with a thick deposited film thickness T and the corresponding low concentration region 41 with a low activator concentration C are superimposed, and ultimately the brightness distribution 50 becomes uniform in the plane.

[0071] Similarly, in the film thickness distribution 30 of the deposited film layer 20, in the thin film region 32 where the deposited film thickness T is thinner than a predetermined reference film thickness value, the activator concentration C in the region of the activator concentration distribution corresponding to the thin film region 32 (high concentration region 42) is set higher than the predetermined reference concentration value. As a result, the two characteristics of the thin film region 32 with a thin deposited film thickness T and the corresponding high concentration region 42 with a high activator concentration C are superimposed, ultimately resulting in a uniform brightness distribution 50 in the plane.

[0072] In this embodiment, the vapor-deposited film layer 20 has a thick film region 33 outside the thin film region 32 of the film thickness distribution 30 described earlier, and a thin film region 34 outside the thick film region 33. Similarly, the activator concentration distribution 40 has a low concentration region 43 outside the high concentration region 42, and a high concentration region 44 outside the low concentration region 43.

[0073] As a result, the film thickness distribution 30 of the deposited film thickness T related to brightness B and the activator concentration distribution 40 of the activator concentration C are correlated across the entire layer 20 of the deposited film layer 20. Consequently, the obtained brightness B and the brightness distribution 50 related to brightness B can be made constant across the entire layer. That is, in Figure 3, brightness B is represented at a constant height from the substrate 10. In Figure 4, the brightness distribution 50 is shown with uniform hatching.

[0074] In the radiation image detector 1 of this embodiment, the vapor-deposited film layer 20 of the scintillator panel 2 may use cesium iodide (CsI) as the phosphor component 22 and Tl (thallium) as the activator component 24. This makes it possible to construct a scintillator panel 2 having a vapor-deposited film layer 20 of activated cesium iodide (CsI:Tl). Note that the combination of phosphor component 22 and activator component 24 is not limited to this, and other well-known phosphor component 22 and activator component 24 may be used in appropriate combinations.

[0075] The reference film thickness value that serves as the basis for the deposited film thickness T in the film thickness distribution 30 can be any predetermined value, for example, the median film thickness calculated based on the deposited film thickness T across the entire layer can be used. On the other hand, the reference concentration value that serves as the basis for the activator concentration C in the activator concentration distribution 40 can be any predetermined value, for example, the median activator concentration calculated based on the activator concentration C across the entire layer of the deposited film layer 20 can be used.

[0076] This makes it possible to define the correlation between the film thickness distribution 30 and the activator concentration distribution 40 based on the median film thickness and / or median activator concentration across the entire layer of the deposited film layer 20. Note that the reference film thickness value and concentration reference value are not limited to these; the average value across the entire layer or predetermined specific values ​​may also be used.

[0077] Furthermore, the vapor-deposited film layer 20 may have a median film thickness in the range of 150 μm to 800 μm, and the activator concentration C may be in the range of 0.1 to 1.5 mol%. By adopting this configuration, the luminance B of light P from the scintillator panel 2 can be kept within ±5% of the median luminance across the entire vapor-deposited film layer 20. This reduces the formation cost of the vapor-deposited film layer 20 and makes it possible to form a scintillator panel 2 with a uniform luminance distribution 50 in the plane.

[0078] In the scintillator panel of this disclosure, the film thickness distribution of the deposited film layer is not limited to the concentric circular film thickness distribution 30 already shown (see Figure 4). For example, the concentric circular film thickness distribution 30 may be further divided in the diametrical direction to obtain a concentric semicircular film thickness distribution 35 (see Figure 5). Alternatively, the concentric semicircular film thickness distribution 35 may be further divided in half to obtain a concentric quarter-circular film thickness distribution 36 (see Figure 6).

[0079] In forming the vapor-deposited film layer 20, based on the vapor deposition image shown in Figure 2, a vapor-deposited film layer 20 having a concentric circular film thickness distribution 30 is formed over a relatively large vapor deposition area, and then it may be divided into two or four sections for use in a scintillator panel. Therefore, a vapor-deposited film layer having a concentric semicircular or concentric quarter-circular film thickness distribution 35, 36 as shown in Figure 5 or Figure 6 may be used. In this case, the activator concentration distribution has corresponding activator concentrations C distributed in the above film thickness distributions 30, 35, and 36.

[0080] Furthermore, the vapor-deposited film layer 60 in this embodiment may have a first vapor-deposited film layer 61 and a second vapor-deposited film layer 62, as shown in Figure 7. The first vapor-deposited film layer 61 has a vapor-deposited film thickness T2 from the substrate surface 10a that is 10% or less of the maximum film thickness T1 from the substrate surface 10a. On the other hand, the second vapor-deposited film layer 62 is laminated on the first vapor-deposited film layer 61, and has a vapor-deposited film thickness T3 from the first vapor-deposited film layer 61 that is greater than 10% and extends to the maximum film thickness T1. In the vapor-deposited film layer 60, the first vapor-deposited film layer 61 does not contain the activator component 24. That is, the activator concentration C in the first vapor-deposited film layer 61 is 0%. By not including the activator component 24 in the first vapor-deposited film layer 61, the independence of the phosphor component 22 (CsI) crystals in the so-called "root portion" close to the substrate surface 10a is improved in the vapor-deposited film thickness T direction (see Figure 2) of the vapor-deposited film layer 60.

[0081] Alternatively, the vapor-deposited film layer 70 in this embodiment may have a third vapor-deposited film layer 71 and a fourth vapor-deposited film layer 72, as shown in Figure 8. The third vapor-deposited film layer 71 has a vapor-deposited film thickness T4 from the substrate surface 10a that is 50% or less of the maximum film thickness T1 from the substrate surface 10a. On the other hand, the fourth vapor-deposited film layer 72 is laminated on the third vapor-deposited film layer 71, and has a vapor-deposited film thickness T5 from the third vapor-deposited film layer 71 that is more than 50% and extends to the maximum film thickness T1. In the vapor-deposited film layer 70, at least 70% or more of the total amount of activating agent component 24 is contained in the third vapor-deposited film layer 71. By having a third vapor-deposited film layer 71 with such a configuration, the activating agent component 24 present in the "root portion" close to the substrate surface 10a greatly contributes to the brightness B of the vapor-deposited film layer 70. In addition, by including most of the activating component 24 in the third vapor-deposited film layer 71, which has a thickness of 50% or less from the substrate surface 10a, it becomes possible to more efficiently convert the X-rays incident from the substrate surface 10a into visible light. Furthermore, if a large amount of the activating component 24 is present on the surface of the vapor-deposited film layer 70 (on the fourth vapor-deposited film layer 72 side), the coloration of the vapor-deposited film layer 70 tends to become relatively larger, and the absorption rate of visible light increases. Therefore, since the brightness may decrease, it is preferable that 70% or more of the activating component 24 be present in the third vapor-deposited film layer 71. [Examples]

[0082] The present disclosure will be described below based on examples, but the present disclosure is not limited to these examples.

[0083] <1> Formation of a vapor-deposited film layer The vapor-deposited film layer of Example 1 was obtained using a manufacturing apparatus based on the vapor deposition image schematically shown in Figure 2. First, a vapor-deposited film layer was formed by vapor-depositing cesium iodide (CsI) as a phosphor component and thallium (Tl) as an activator component onto one side (substrate surface) of a polyimide resin sheet (thickness: 125 μm) that would serve as the substrate.

[0084] Specifically, the substrate to be vapor-deposited was placed on a support substrate equipped with a support substrate rotation mechanism inside a vacuum chamber. Next, the phosphor component and the activator component were filled into evaporation source crucibles (evaporation sources) as vapor-depositing materials, respectively, and positioned near the inside of the vacuum chamber, at the center of a center line (rotation axis) perpendicular to the support substrate and on the circumference of a circle with this center as the axis (see Figure 2). At this time, the distance between the substrate and the evaporation source (evaporation source-substrate distance) was adjusted to 400 mm, and the distance between the center line (rotation axis) perpendicular to the substrate and the evaporation source was also adjusted to 400 mm. Subsequently, the inside of the vacuum chamber was evacuated, Ar gas was introduced to adjust the vacuum level to 0.1 Pa, and the substrate temperature was maintained at 30°C while rotating the substrate at a speed of 10 rpm.

[0085] Next, the temperature inside the evaporation source crucible was raised to 700°C by resistance heating, and with the substrate rotating, deposition of phosphor and activator components was started from a total of four evaporation sources. Deposition was terminated when the deposition film thickness of the deposited film layer reached 400 μm.

[0086] Subsequently, the vapor-deposited film layer (phosphor layer) was placed in a protective layer bag (a protective layer bag made of a laminated film of polyethylene terephthalate (PET) and cast polypropylene (CPP)) in dry air, and the periphery was sealed by fusion using an impulse sealer under reduced pressure, thereby obtaining a vapor-deposited film layer with a sealed phosphor layer structure.

[0087] The vapor-deposited film layers of Comparative Examples 1 and 2 were obtained using a manufacturing apparatus based on the vapor deposition image schematically shown in Figure 9. While the vapor-deposited film layer of Example 1 utilized a total of four evaporation sources, the vapor-deposited film layers of Comparative Examples 1 and 2 were obtained using a total of two evaporation sources, as shown in Figure 9. The changes in vapor deposition film thickness, activator concentration, and brightness in the vapor-deposited film layers of Comparative Examples 1 and 2 are schematically shown in Figure 10.

[0088] In Comparative Example 1, the evaporation source-substrate distance in the evaporated film layer was set to 400 mm, the same as in Example 1. On the other hand, in Comparative Example 2, the evaporation source-substrate distance in the evaporated film layer differed from that of Example 1 and Comparative Example 1, being set to 800 mm. In other words, the evaporated film layer of Example 1 and the evaporated film layer of Comparative Example 1 differed only in the number of evaporation sources positioned relative to the substrate surface, while all other conditions were the same. On the other hand, the evaporated film layer of Comparative Example 1 and the evaporated film layer of Comparative Example 2 differed only in the evaporation source-substrate distance, while all other conditions were the same.

[0089] [Table 1]

[0090] The vapor-deposited film layer obtained in Example 1 was adjusted so that the activator concentration in the region corresponding to the thick film region (low concentration region) was in the range of 0.2 to 0.4 mol%, and the activator concentration in the region corresponding to the thin film region (high concentration region) was in the range of 0.5 to 0.8 mol%.

[0091] On the other hand, in Comparative Examples 1 and 2, as shown in Figure 10, in a virtual lateral cross-sectional view, the central deposition position b0, which is the center of rotation, has the thickest deposition film T, and the deposition film T gradually decreases as it moves radially outward. Furthermore, because the first activator evaporation source 25 is located on the axial extension line opposite to the first deposition position b1, there are regions with high activator concentration C concentrically around the central deposition position b0. Therefore, even if these are added together, the luminance B does not form a plane, and the luminance distribution of light P is biased.

[0092] <2> Half film thickness range of activator concentration As specifically shown in Figure 8, the vapor-deposited film layers of Example 1 and Comparative Examples 1 and 2 have a third vapor-deposited film layer with a thickness of 50% or less of the maximum film thickness T1 from the substrate surface. This third vapor-deposited film layer contains at least 70% of the total amount of activating components contained in each vapor-deposited film layer.

[0093] <3> Evaluation of the utilization efficiency of phosphorescent components The utilization efficiency of the phosphor component in the vapor-deposited film layers obtained in Example 1 and Comparative Examples 1 and 2 was evaluated based on the following evaluation criteria. According to this evaluation, the vapor-deposited film layers of Example 1 and Comparative Example 1, where the evaporation source-substrate distance was short, were evaluated as having good (=OK) utilization efficiency of the phosphor component. On the other hand, the vapor-deposited film layer of Comparative Example 2, where the evaporation source-substrate distance was long, was evaluated as having poor (=NG) utilization efficiency of the phosphor component. <Evaluation Criteria for the Utilization Efficiency of Fluorescent Components> The utilization efficiency of the phosphor component was determined by measuring the weight of the scintillator base material (cesium iodide) and activator used as the evaporation source before and after deposition using an electronic balance (GF-6100: manufactured by A&D Co., Ltd.), and measuring the weight X (g) of the scintillator material used for evaporation. Next, the weight Y (g) of the scintillator after deposition was measured. Based on the obtained measurement results, the ratio of weight Y (g) to weight X (g) was defined as the utilization efficiency. A utilization efficiency of 10% or more for weight Y (g) to weight X (g) was evaluated as good (=OK), and a utilization efficiency of less than 10% was evaluated as poor (=NG).

[0094] <4> Brightness distribution evaluation The brightness distribution of the vapor-deposited film layers obtained in Example 1 and Comparative Examples 1 and 2 was evaluated based on the following evaluation criteria. According to this evaluation, the vapor-deposited film layers of Example 1 and Comparative Example 2 received a good (=OK) evaluation for having a uniform brightness distribution. On the other hand, the vapor-deposited film layer of Comparative Example 1 received a poor (=NG) evaluation for having an uneven brightness distribution. <Evaluation Criteria for Brightness Distribution> As an example, in an image with an effective image area of ​​420mm x 420mm, the entire effective image area was divided into 100 pixels x 100 pixels ROIs (Regions of Interest), and the median value of each ROI was calculated. Then, the maximum value ROI_MAX and the minimum value ROI_MIN from the calculated median ROIs were divided by the median brightness of the radiation image detector (FPD brightness) to obtain the brightness distribution. The value of ROI_MAX - median FPD brightness / median FPD brightness was evaluated as good (=OK) if it was 5% or less, and ROI_MIN - FPD / median FPD brightness was -5% or more. All other cases were evaluated as unacceptable (=NG).

[0095] <5> comprehensive evaluation As shown in the evaluation results above, the radiation image detector of this disclosure demonstrates that by correlating the film thickness distribution and activator concentration distribution of the vapor-deposited film layer constituting the scintillator panel, a vapor-deposited film layer with good utilization efficiency and brightness distribution of the phosphor component can be obtained. The radiation image detector of this disclosure is particularly suitable for scintillator panels having a vapor-deposited film layer with a large deposition area. If both the evaluation of the utilization efficiency of the phosphor component and the evaluation of the brightness distribution are good, the overall evaluation is evaluated as good (=OK). If either the evaluation of the utilization efficiency of the phosphor component or the evaluation of the brightness distribution is unsatisfactory, the overall evaluation is evaluated as unsatisfactory (=NG). [Explanation of Symbols]

[0096] 1. Radiation imaging detector 2 scintillator panels 3 cabinets 10 circuit boards 10a Substrate surface 10b Incidence plane 20,60,70 Deposited film layer 21 Support substrate 22. Fluorescent components 23a First phosphor evaporation source 23b Second phosphor evaporation source 24. Activating ingredients 25a First activator evaporation source 25b Second activator evaporation source 30,35,36 Film thickness distribution 31,33 Thick film field 32,34 Thin Film Field 40. Concentration distribution of activator 41,43 Low concentration areas 42,44 High concentration areas 50 luminance distribution 61 First Evaporated Film Layer 62 Second Evaporated Film Layer 71 Third Evaporated Film Layer 72 Fourth Evaporated Film Layer B luminance C activator concentration L Evaporation source-substrate distance P light R radiation T, T2, T3, T4, T5 evaporated film thickness T1 maximum film thickness X-axis a0, b0 Center Evaporation Position a1, b1 First steaming position a1', b1' reverse first evaporation position a2 Second steaming position a2' Reverse second evaporation position a3 Third steaming position a3' Reverse third evaporation position

Claims

1. circuit board and A vapor-deposited film layer is formed on the substrate surface of the aforementioned substrate by depositing a phosphor component together with an activator component in a film-like manner. Equipped with a scintillator panel having, The deposition film thickness corresponding to the thickness of the deposition film layer from the substrate surface is, The thickness of the aforementioned vapor-deposited film layer is set to be within ±10% of the median film thickness across the entire layer. A radiation image detector in which the film thickness distribution relating to the deposition film thickness and the activator concentration distribution relating to the activator concentration of the activator component in the deposition film layer are correlated.

2. The correlation between the film thickness distribution and the activator concentration distribution is, If the deposition film thickness in a specific region of the deposition film layer is thicker than the reference film thickness value, the activator concentration in the specific region is set lower than the reference concentration value. The radiation image detector according to claim 1, wherein if the deposition film thickness in the specific region is thinner than the reference film thickness value, the activator concentration in the specific region is set higher than the reference concentration value.

3. The aforementioned phosphor component is, Cesium iodide was used, The aforementioned activating agent component is A radiation image detector according to claim 1, wherein thallium is used.

4. The aforementioned reference film thickness value is, Using the median film thickness, The aforementioned reference concentration value is, The radiation image detector according to claim 2, wherein the median concentration of the activator across the entire layer of the vapor-deposited film layer is used.

5. The median thickness of the aforementioned vapor-deposited film layer is, The size is 150-800 μm. The concentration of the activator in the vapor-deposited film layer is It is 0.1 to 1.5 mol%, The brightness of the scintillator panel having the aforementioned vapor-deposited film layer is The radiation image detector according to claim 1, wherein the brightness is within ±5% of the median brightness value across the entire layer of the deposited film layer.

6. The distribution of the film thickness is, It is at least one of the following: concentric circles, concentric semicircles, and concentric quarter circles. The aforementioned activator concentration distribution is, A radiation image detector according to claim 1, corresponding to the aforementioned film thickness distribution.

7. The aforementioned vapor-deposited film layer is A first vapor-deposited film layer whose vapor-deposited film thickness from the substrate surface is 10% or less of the maximum film thickness from the substrate surface, A second vapor-deposited film layer is laminated on the first vapor-deposited film layer, and the vapor-deposited film thickness from the first vapor-deposited film layer is greater than 10% up to the maximum film thickness, It has, The first vapor-deposited film layer is A radiation image detector according to claim 1, which does not contain the aforementioned activating agent component.

8. The aforementioned vapor-deposited film layer is A third vapor-deposited film layer having a vapor-deposited film thickness of 50% or less of the maximum film thickness from the substrate surface, A fourth vapor-deposited film layer is laminated on the third vapor-deposited film layer, and the vapor-deposited film thickness from the third vapor-deposited film layer is from more than 50% to the maximum film thickness, It has, The radiation image detector according to claim 1, wherein at least 70% or more of the activating component is contained in the third vapor-deposited film layer relative to the total amount of the activating component contained in the vapor-deposited film layer.

Images