JP2004077236A - Method of manufacturing deposition phosphor layer - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a phosphor layer manufacturing method for preventing the deterioration in information in reading radioactive ray image information from a phosphor sheet, uniformizing the thickness in a phosphor layer, further actually, having the thickness of about 500 μm in an ordinary case and even 1,000 μm in a thick case, and realizing a superior optical characteristic. <P>SOLUTION: The phosphor layer manufacturing method is characterized by polishing a surface of the phosphor layer after forming a film by forming the phosphor layer as the film on a sheet-like base board in a vacuum chamber. The surface of the phosphor layer is desirably polished by relatively moving a polishing material and the base board in a state of positioning the polishing material at a prescribed interval between the surface and a prescribed reference surface. <P>COPYRIGHT: (C)2004,JPO

Description

[0001]
BACKGROUND OF THE INVENTION
The present invention relates to the field of vapor-deposited phosphor layer manufacturing technology, and more specifically, is effective in forming a phosphor layer (phosphor film) on a substrate by vacuum deposition, and obtains a high-quality phosphor layer. The present invention relates to a method for manufacturing a phosphor layer.
[0002]
[Prior art]
When irradiated with radiation (X-rays, α-rays, β-rays, γ-rays, electron beams, ultraviolet rays, etc.), a part of this radiation energy is accumulated, and then irradiated with excitation light such as visible light, Phosphors that exhibit stimulated luminescence according to the stored energy are known. This phosphor is called a storage phosphor (stimulable phosphor) and is used for various applications such as medical applications.
[0003]
As an example, a radiation image information recording / reproducing system using a sheet (referred to as a phosphor sheet or a radiation image conversion sheet) having a layer (that is, a phosphor layer) containing the stimulable phosphor is known. For example, it has been put to practical use as FCR (Fuji Computed Radiography Fuji Photo Film Co., Ltd.).
In this system, radiographic image information of a subject such as a human body is recorded on a phosphor sheet, and after recording, the phosphor sheet is scanned two-dimensionally with excitation light such as laser light to generate stimulated emission light. An image signal is obtained by photoelectrically reading the photostimulated luminescence light, and an image reproduced based on the image signal is displayed on a recording material such as a photographic photosensitive material or a display device such as a CRT. Output as.
[0004]
Such a phosphor sheet is usually prepared by dispersing a stimulable phosphor powder in a solvent containing a binder and the like, and applying the paint to a sheet-like support made of glass or resin. It is produced by drying to form a phosphor layer.
On the other hand, a phosphor sheet in which a phosphor layer is formed on a support by a physical vapor deposition method (vapor deposition method) such as vacuum deposition or sputtering is also known (Japanese Patent No. 2789194, Japanese Patent Laid-Open No. 5). -Refer to each publication such as -249299). Since the phosphor layer produced by vapor deposition is formed in a vacuum, there are few impurities, and since there are almost no components other than the storage phosphor such as a binder, there is little variation in performance, and the luminous efficiency is low. It has the excellent feature of being very good.
[0005]
In general, vacuum deposition is used as a method for forming a thin film in various fields such as coating of optical parts, manufacture of magnetic recording media and electronic displays. In the film formation by vapor deposition in these, in most cases, the thickness of the film to be formed is 1 μm or less, and at most about 3 μm.
On the other hand, the phosphor layer of the phosphor sheet formed by vacuum deposition needs to have a thickness of 200 μm or more, usually about 500 μm, even if it is thin, and a thickness of 1000 μm.
[0006]
The present applicant has previously proposed a method or an apparatus for producing a phosphor sheet that can be suitably used for the formation of such a phosphor layer (manufacture of a phosphor film) (for example, Japanese Patent Application No. 2002-4291, No. 2002-19631).
These techniques are related to a phosphor sheet manufacturing technique by so-called binary vapor deposition. In the vacuum chamber, evaporation means for heating and evaporating the phosphor film-forming material and heating the activator film-forming material are heated. The present invention proposes an apparatus provided with an evaporating means for evaporating and a substrate holding / rotating means.
[0007]
[Problems to be solved by the invention]
By the way, in the above-mentioned FCR system, as described above, radiation image information is recorded on the phosphor sheet, and after the recording, the phosphor sheet is scanned two-dimensionally with excitation light such as a laser beam, so as to emit light. Light is generated, and the photostimulated light is photoelectrically read to obtain an image signal, and an image reproduced based on the image signal is transferred to a recording material such as a photographic photosensitive material or a display device such as a CRT. Output as a visible image of the radiation image.
[0008]
The problem here is that when reading the radiation image information from the above-mentioned phosphor sheet, the distance between the reading head (light receiving portion) and the phosphor layer surface on the phosphor sheet needs to be uniform. That is.
However, when the thick phosphor layer as described above is formed by vapor deposition, especially when a large-sized phosphor sheet having the thick phosphor layer as described above is manufactured, the entire surface is formed. It is difficult to form a film with a uniform thickness, and the current limit is to keep the film thickness distribution within about ± 3%.
[0009]
When reading the image information recorded on the phosphor sheet, as shown in FIG. 4, a light beam (excitation) is applied to the phosphor layer 94 formed on the substrate of the phosphor sheet 90 from a light beam irradiation means (not shown). The line CCD sensor 96 reads the generated photostimulated light.
At this time, the distance A between the line CCD sensor 96 and the surface of the phosphor sheet 90 is about 100 μm. On the other hand, if the thickness of the phosphor layer 94 is about 500 μm, the variation width B of the thickness of the phosphor layer 94 is about 30 μm because the above-mentioned thickness distribution is about ± 3%. Therefore, since the distance A between the line CCD sensor 96 and the surface of the phosphor sheet 90 varies greatly depending on the location, there is a problem that the image is blurred. For this reason, it is desirable to make the fluctuation range of the film thickness of the phosphor layer 94 as small as possible.
[0010]
Further, depending on the film forming conditions, a projection-like surface roughness called splash (bump boiling) may occur due to the influence of foreign matters contained in the material during film formation. When such a splash occurs, excitation light or stimulated emission light is scattered at the time of reading, and information deterioration (such as blurring of an image) also occurs at the time of reading by the reading head.
[0011]
The present invention has been made in view of the above circumstances, and an object thereof is to prevent deterioration of information when reading radiation image information from a phosphor sheet, and more specifically. An object of the present invention is to provide a method for producing a phosphor layer having excellent optical characteristics by making it possible to realize uniformity of thickness in a phosphor layer having a thickness of about 500 μm ordinarily about 1000 μm.
[0012]
[Means for Solving the Problems]
In order to achieve the above object, a method for producing a phosphor layer according to the present invention comprises depositing a phosphor layer on a sheet-like substrate by vapor deposition in a vacuum chamber, and polishing the surface of the phosphor layer after film formation. It is characterized by doing.
[0013]
Here, in the method for manufacturing a phosphor layer according to the present invention, the surface of the phosphor layer is polished, and the surface of the phosphor layer is polished to obtain a phosphor layer having a predetermined uniform thickness, and the phosphor layer is polished. In order to remove protrusions on the surface of the body layer, specifically, the polishing material is placed in a state where the polishing material is located at a predetermined interval from a predetermined reference surface. It is preferable to carry out by relatively moving the substrate and the substrate. Further, as a polishing material used for polishing the surface of the phosphor layer, a polishing material having a width exceeding the width of the phosphor layer is used, and the phosphor having the phosphor layer formed on the polishing material and the substrate It is preferable that the sheet is moved relatively in the length direction orthogonal to the width direction of the phosphor layer.
[0014]
According to the present invention having such a configuration, when the phosphor sheet is manufactured, the surface of the phosphor layer after film formation is polished to smooth the surface of the phosphor sheet to a predetermined uniform thickness. Since the distance between the reading head and the phosphor sheet is uniform, information is not deteriorated (such as unevenness in the image) at the time of reading by the reading head, and an advantageous effect that good reading is possible is obtained. .
[0015]
DETAILED DESCRIPTION OF THE INVENTION
Hereinafter, embodiments of the present invention will be described in detail with reference to the accompanying drawings. In the following explanation, first, after explaining the outline of the process of forming a phosphor sheet by forming a phosphor film on a sheet-like substrate by a vacuum vapor deposition apparatus, the fluorescence of the prepared phosphor sheet is explained. The process of polishing the body layer will be described in detail.
[0016]
In FIG. 2, the conceptual diagram of the fluorescent substance sheet manufacturing apparatus which actualized the manufacturing method of the fluorescent substance sheet which is the 1st step of the manufacturing method of the vapor deposition fluorescent substance layer which concerns on one Embodiment of this invention is shown.
The phosphor sheet manufacturing apparatus (hereinafter also simply referred to as a manufacturing apparatus) 10 in the illustrated example is a vacuum deposition type manufacturing apparatus proposed by the present applicant in Japanese Patent Application Nos. 2002-4291 and 2002-19631. It is based on.
[0017]
That is, the manufacturing apparatus according to the present embodiment forms a stimulable phosphor layer by binary vapor deposition on the surface of a sheet-like substrate (here, a glass substrate) S, and (accumulative) phosphor sheet. Basically, a so-called substrate rotation type vacuum vapor deposition apparatus configured to include a vacuum chamber 12, a substrate holding / rotating mechanism 14, and a heating evaporation unit 22 is used. .
[0018]
The vacuum chamber 12 is connected to a vacuum pump (evacuation means) (not shown) for exhausting the system to a predetermined degree of vacuum.
In addition, in the manufacturing apparatus 10 shown in the drawing, as an example, binary vacuum deposition using cesium bromide (CsBr) and europium bromide (EuBr _x (x is usually 2 to 3)) as a film forming material is performed. Then, a phosphor layer using CsBr: Eu as the stimulable phosphor is formed on the glass substrate S to produce a phosphor sheet.
[0019]
In the phosphor sheet produced by the production apparatus according to the present invention, the stimulable phosphor is not limited to the above CsBr: Eu, and various types can be used.
Preferably, a stimulable phosphor that exhibits stimulated emission in the wavelength range of 300 nm to 500 nm upon irradiation with excitation light having a wavelength in the range of 400 nm to 900 nm is used. Such photostimulable phosphors are described in detail in JP-B-7-84588, JP-A-2-193100, and JP-A-4-310900.
[0020]
Returning to FIG. 2, the description will be continued. The vacuum chamber 12 is a known vacuum chamber (bell jar, vacuum chamber) that is formed of iron, stainless steel, aluminum, or the like and is used in a vacuum deposition apparatus.
In the illustrated example, in the vacuum chamber 12, a substrate holding / rotating mechanism 14 is disposed above, and a heating evaporation unit 22 is disposed below. In addition, although the case where only one set of the heating evaporation unit 22 is illustrated here, it is needless to say that a plurality of heating evaporation units 22 may be provided.
[0021]
The substrate holding / rotating mechanism 14 holds and rotates the glass substrate S, and includes a rotation drive source (motor) 28 a and a turntable 30.
The turntable 30 is a disc composed of a main body 32 that holds the upper glass substrate S and a lower (heat evaporation unit 22 side) sheath heater 34, and a rotary shaft 28 that engages with a motor 28a is fixed at the center thereof. Is done. The turntable 30 holds the glass substrate S on the lower surface (the lower surface of the sheath heater 34) at a predetermined position corresponding to a heating evaporation unit 22 (evaporation position of the film forming material), which will be described later, and rotates at a predetermined speed by the rotation shaft 28. Is done. The sheath heater 34 heats the glass substrate S to be formed from the back surface (the surface opposite to the film forming surface). The glass substrate S may be held on the turntable 30 (the lower surface of the sheath heater 34) with the film formation surface facing downward by a method using a known jig 14a or the like (see FIG. 2).
[0022]
A pair (two) of heating and evaporating units 22 are arranged below the substrate holding / rotating mechanism 14 in the vacuum chamber. In FIG. 3, the conceptual diagram of the heating evaporation part 22 is shown. 3A is a top view (viewed from above in FIG. 1), and FIG. 3B is a front view (viewed in the same direction as FIG. 2).
As described above, the manufacturing apparatus 10 according to the present embodiment uses cesium bromide and europium bromide as film forming materials, and performs binary vacuum evaporation in which these are individually heated and evaporated. The heating evaporation unit 22 includes a europium evaporation unit (hereinafter referred to as Eu evaporation unit) 38, a cesium evaporation unit (hereinafter referred to as Cs evaporation unit) 40, and a material supply device 46.
[0023]
The Eu evaporation section 38 is a portion that causes the resistance heating device 42 to evaporate the europium bromide (activator material) accommodated in the evaporation position Pe (crucible) by resistance heating. Here, the resistance heating device 42 for resistance heating and evaporating the activator material is not particularly limited, and a vacuum deposition device can be used as long as it can be suitably evaporated according to the activator material used. Various types used in the can be used.
Moreover, there is no restriction | limiting in particular also in the output at the time of performing resistance heating, What is necessary is just to set suitably according to activator material etc., but in the example of illustration (it changes with resistance values of a heater), about 50A-1000A do it.
[0024]
On the other hand, the Cs evaporation unit 40 is an electron beam heating device that heats and evaporates cesium bromide, which is a phosphor material, by irradiating the evaporation position Pc (Haas) with an electron beam (EB) emitted from the electron gun 44. is there.
The manufacturing apparatus 10 according to the present embodiment employs dual evaporation in which the phosphor material and the activator material are separately heated and evaporated in the manufacture of the phosphor sheet in which the phosphor layer is formed by vacuum deposition, and the activation is performed. The activator material is heated and evaporated by resistance heating, and the phosphor material is heated and evaporated by electron beam heating, so that the activator is uniformly dispersed in the phosphor layer (that is, in the phosphor). The phosphor sheet can be manufactured efficiently.
[0025]
In the manufacturing apparatus 10 according to the present embodiment, the Cs evaporation unit 40 can basically use various known evaporation means as long as the Cs evaporation unit 40 performs heating with an electron beam.
Therefore, the electron gun is not particularly limited, and is used in vacuum deposition, such as a 180 ° deflection gun that deflects an electron beam by 180 ° and enters the evaporation position, a 270 ° deflection gun, and a 90 ° deflection straight gun. Various electron guns are available. In the illustrated example, the electron gun 44 uses a 270 ° deflection gun as an example.
[0026]
There is no limitation on the emission current of the electron gun 44 and the accelerating voltage of the EB as long as it is sufficient according to the film forming material and the film thickness to be formed.
In the illustrated example, as an example, it is preferable that the acceleration voltage of EB is −1 KV to −30 KV, and the emission current is 50 mA to 2 A for the Cs evaporation unit 30.
[0027]
Here, as described above, the phosphor layer formed on the phosphor sheet is much thicker than a normal vacuum deposited film, and is about 200 μm at most, usually about 500 μm, and about 1000 μm when it is thick. It may exceed. Further, the activator and the phosphor are, for example, about 0.0001 / 1 to 0.01 / 1 in molar concentration ratio, and most of the phosphor layer is the phosphor. Therefore, in the manufacturing apparatus 10 of the illustrated example, as a preferable aspect, the Cs evaporation unit 40 includes a material supply unit 46 that is a supply unit of cesium bromide.
[0028]
In the illustrated example, the material supply means 46 basically includes a cylinder 48, a piston 50, a casing 52, and an elevating means (motor) 54.
The cylinder 48 is a cylinder fixed to the wall surface of the vacuum chamber 12 in a state where a part of the cylinder 48 protrudes outside through the lower surface of the vacuum chamber 12 so that the upper end portion thereof coincides with the electron beam irradiation position. . That is, in the illustrated example, the cylinder 48 is a so-called hearth, and the upper end portion thereof is the cesium bromide evaporation position Pc.
[0029]
The piston 50 includes a columnar piston head 50a that is loosely fitted in the cylinder 48, and a piston pin 50b that fixes the piston head 50a to the tip. The piston pin 50b engages with an elevating means 54 that elevates and lowers the piston 50 (in the direction of arrow a).
Further, the open end of the cylinder 48 is covered with a casing 52 so that the inside of the vacuum chamber 12 is kept airtight, and the piston pin 50b is airtightly attached to the casing 52 so as to reciprocate in the up and down direction by a bearing (not shown). Be supported.
[0030]
The cesium bromide is molded into a cylindrical shape having a slightly smaller diameter than the inner diameter of the cylinder 48, and is accommodated in the cylinder 48 while being placed on the piston head 50a.
When cesium bromide at the evaporation position Pc is consumed by the film formation on the substrate, the elevating means 54 is driven accordingly to raise the columnar cesium bromide. Thus, cesium bromide is always supplied to the upper surface of the cylinder 48, that is, the evaporation position, and it is possible to suitably cope with the formation of a thick film exceeding 200 μm.
[0031]
As described above, in the phosphor sheet, the amount of activator is extremely small with respect to the phosphor, and component control of the phosphor layer is important. According to the study by the present inventors, in order to form a high-quality phosphor layer having a thickness exceeding 200 μm in which an activator is uniformly dispersed and added (dope) in the phosphor, It is preferable that vapor is separately generated for the film forming material and the film forming material for the activator to generate a mixed vapor in which both are sufficiently mixed, and the mixed vapor is used to form a film on the substrate.
[0032]
In addition, here, by evaporating the phosphor material with a large amount of deposition by electron beam heating, the evaporation can be performed with good controllability and efficiency, and the film formation can be controlled more suitably. become. On the other hand, resistance heating can disperse and evaporate a very small amount of film-forming material with high spatial uniformity. Therefore, by using this as a heating means for the activator material, a small amount of deposition material is added to the mixed vapor. It is possible to form a high-quality phosphor layer in which the activator material vapor is suitably dispersed to more uniformly disperse the activator.
[0033]
Next, a polishing apparatus that polishes the phosphor layer of the prepared phosphor sheet, which is the second stage of the method for producing a vapor-deposited phosphor layer according to the present embodiment, will be described.
[0034]
FIG. 1 is a schematic side view showing a polishing process of a vapor-deposited phosphor layer according to the present embodiment. Here, as an example, the surface of the phosphor layer 64a of a phosphor sheet 64 of 430 mm square is fed and taken up. A long polishing material (wrapping sheet) 62 having a width of 450 mm transferred by the driving mechanism is used for polishing.
That is, in the illustrated polishing step, the surface of the phosphor sheet 64 locked on the sheet support base 66 (actually, the surface of the phosphor layer 64 a on the phosphor sheet 64) has the above-described long length. Polishing is performed using a polishing apparatus 60 that also moves itself while driving the polishing material 62 in contact.
[0035]
Here, the above-described polishing apparatus 60 is positioned so as to position and contact the polishing material 62 with respect to the phosphor sheet 64, the feeding portion 60 a that feeds the long polishing material 62, the winding portion 60 b that winds the polishing material 62. Further, the polishing apparatus 60 as a whole is configured in the direction of arrow a in the drawing (direction along one center line of the phosphor sheet 64) by a moving mechanism in a horizontal plane (not shown). Are configured to reciprocate. A predetermined clearance (a distance indicated by P in the drawing) between the polishing material 62 and the reference surface of the phosphor sheet 64 (for example, the bottom surface of the phosphor sheet 64 or the surface of the sheet support base 66). It is comprised so that it may hold | maintain and move so that it may have and may grind | polish.
[0036]
The value of P may be appropriately determined depending on the characteristics of the polishing material 62 to be used and the characteristics of the phosphor layer 64a to be polished.
Specifically, as shown in FIG. 1, a total value of a preferable thickness (average thickness) t of the phosphor layer and a thickness St of the substrate S, that is, P = t + St, and this value is the above-described reference plane. Set between.
[0037]
As a moving mechanism of the polishing apparatus 60 here, a known various mechanism such as a mechanism using a rack and pinion, a mechanism using a ball screw, or the like may be used to convert the rotation of a motor or the like as a driving source. Also, the movement may be in one direction, or a reciprocating movement that periodically switches the movement direction. In this case, the moving direction switching speed (frequency) may be appropriately determined.
The relative movement speed (abrasion material contact speed) between the phosphor sheet 64 and the polishing material 62 may be appropriately determined according to the characteristics of the phosphor layer and the characteristics of the polishing material. In the case of the phosphor layer (CsBr: Eu) shown in the form, since it is relatively soft, a considerable polishing rate can be obtained even at a low speed.
[0038]
Hereinafter, the phosphor layer deposition procedure in the manufacturing apparatus configured as described above and the polishing procedure in the polishing apparatus will be described.
As described above, the manufacturing apparatus 10 uses a rotary vacuum deposition apparatus. When manufacturing a phosphor sheet, first, a film formation surface is formed on the lower surface of the turntable 30 of the substrate holding / rotating mechanism 14. After the glass substrate S is mounted facing downward, the vacuum chamber 12 is closed and decompressed, and the sheath heater 34 is driven to heat the glass substrate S from the back surface.
[0039]
When the inside of the vacuum chamber 12 reaches a predetermined degree of vacuum, while the turntable 30 is rotated at a predetermined speed by the motor 28a, the heating and evaporation unit 22 drives the resistance heating device 42 of the Eu evaporation unit 38 to evaporate the position Pe. The europium bromide accommodated in the (crucible) is evaporated, and the electron gun 44 of the Cs evaporation unit 40 is driven to evaporate cesium bromide at the evaporation position Pc, thereby depositing CsBr: Eu on the substrate S, that is, The film formation of the phosphor layer is started.
[0040]
Here, as described above, both evaporation positions are arranged close to each other, and the evaporation of europium bromide is performed by resistance heating. Therefore, a very small amount of vapor of europium bromide is uniformly distributed in the heating evaporation unit 22. A mixed vapor of both film forming materials is formed, and CsBr: Eu in which the activator is uniformly dispersed is deposited by the mixed vapor.
When the phosphor film having a predetermined thickness is formed, the rotation of the turntable 30 is stopped, the vacuum chamber 12 is opened, and the glass substrate S on which the phosphor layer has been formed is taken out. In the case where film formation is performed continuously, the film formation may be performed by loading a new glass substrate S in the same manner as above.
[0041]
The glass substrate S on which the phosphor layer is formed in the above process, that is, the phosphor sheet 64 is subjected to a polishing process by the polishing apparatus 62 after a predetermined time has elapsed.
The phosphor sheet 64 in this embodiment is set by, for example, locking the phosphor sheet 64 to the sheet support base 66 with a known locking member. Next, the position of the polishing apparatus 60 is adjusted so that the above-mentioned clearance P is set in advance, and the polishing apparatus 60 is set to have a necessary polishing amount. This position adjustment may be performed, for example, by a method such as placing the polishing apparatus 60 on a guide rail provided at a preset position.
[0042]
When the setting of the phosphor sheet 64 and the positioning of the polishing device 60 are completed, first, the feeding of the polishing material 62 in the polishing device 60 is started, and further, the above-described movement (reciprocating) mechanism not shown is started. Then, the polishing apparatus 60 is driven rightward in the drawing from the state of FIG. 1A to start polishing the surface of the phosphor layer 64a of the phosphor sheet 64 with the polishing material 62. Normally, polishing is completed when the polishing apparatus 60 finishes passing over the phosphor sheet 64.
[0043]
In the polishing process of the phosphor layer according to this embodiment configured as described above, the phosphor layer 64a of the phosphor sheet 64 produced in the preceding vapor deposition process is fed with the polishing material 62 in the polishing apparatus 60, The polishing is performed to a predetermined thickness based on the above-described clearance P by the two operations of moving the polishing apparatus 60 itself.
By this polishing operation, the thickness of the phosphor layer 64a of the phosphor sheet 64 is made uniform, and surface roughness such as protrusions due to splash or the like is also eliminated, and the phosphor sheet layer 64a capable of good image reading. A phosphor sheet 64 having the following is obtained.
[0044]
In order to perform the polishing operation of the phosphor layer 64a of the phosphor sheet 64 more smoothly, the position of the polishing apparatus 60 is not set from the beginning to the final target thickness, but the position is adjusted step by step. May be programmed. In the case of such a configuration, the position of the polishing apparatus 60 is gradually lowered with the progress of polishing (or at a predetermined timing).
[0045]
Here, the roughness of the wrapping sheet used when performing surface polishing and the polishing time of the phosphor sheet 64 using the lapping sheet may be determined by experimental measurement in advance.
Further, the number of times the wrapping sheet is repeatedly used may be determined experimentally to some extent.
[0046]
According to the above embodiment, the phosphor layer on the phosphor sheet produced by vapor deposition is finished to a predetermined thickness (uniform thickness), and from the surface, the projection-like shape generated during film formation This brings about a remarkable effect that a phosphor sheet having a phosphor layer with a good surface state can be obtained by removing foreign substances.
In addition, according to the above embodiment, even when there is uneven thickness or waviness on the base substrate, it is possible to obtain a phosphor sheet having excellent surface flatness by absorbing it. It is what you play.
[0047]
The above embodiment shows an example of the present invention, and the present invention should not be limited to this, and appropriate modifications or improvements may be made without departing from the scope of the present invention. Needless to say.
For example, in the above-described embodiment, a polishing apparatus using a long wrapping sheet (wrapping tape) is taken as an example. However, in addition to this, rotation is performed in a plane parallel to the phosphor layer surface of the phosphor sheet. A method using a polishing sheet (or grindstone) to be used, a method of reciprocating a flat wrapping sheet (so-called wrapping plate), and the like can be used.
[0048]
【The invention's effect】
As described above in detail, according to the present invention, it is possible to realize a uniform thickness in a phosphor layer having a thickness of about 500 μm, or about 1000 μm when it is thick, and excellent optical characteristics based thereon. The phosphor layer has a remarkable effect of realizing the manufacturing method of the phosphor layer.
[0049]
More specifically, by polishing the surface of the phosphor layer of the phosphor sheet after film formation, the non-uniformity of the thickness is eliminated, and protrusions and the like generated due to foreign matters during film formation are eliminated. It is possible to efficiently produce a phosphor sheet having an extremely high quality phosphor layer that is removed to realize a good surface state and has stable optical characteristics.
[Brief description of the drawings]
FIGS. 1A and 1B are explanatory views of a polishing process for a deposited phosphor layer according to an embodiment of the present invention.
FIG. 2 is a diagram showing a concept of a phosphor sheet manufacturing apparatus according to an embodiment.
FIG. 3 is a conceptual diagram of a heating evaporation unit according to the embodiment.
FIG. 4 is an explanatory diagram of information reading from a phosphor sheet.
[Explanation of symbols]
DESCRIPTION OF SYMBOLS 10 Manufacturing apparatus 12 Vacuum chamber 14 Substrate holding | maintenance / rotation mechanism 22 Heating evaporation part 28a Motor 30 Turntable 34 Sheath heater 38 Eu evaporation part 40 Cs evaporation part 42 Resistance heating apparatus 44 Electron gun 46 Material supply means 60a Polishing material sending part 60b Polishing material Winding portion 60c Abrasive material contact portion 62 Abrasive material 64 Phosphor sheet 64a Phosphor layer 66 Sheet support

Claims (3)

A method for producing a vapor-deposited phosphor layer, comprising depositing a phosphor layer on a sheet-like substrate in a vacuum chamber by vapor deposition, and polishing the surface of the phosphor layer after the film formation. Polishing of the surface of the phosphor layer is performed by relatively moving the polishing material and the substrate in a state where the polishing material is located at a predetermined interval between the predetermined reference surface. The method for producing a deposited phosphor layer according to claim 1, wherein the method is performed. As a polishing material used for polishing the surface of the phosphor layer, a polishing material having a width exceeding the width of the phosphor layer is used, and the polishing material and a phosphor sheet in which the phosphor layer is formed on the substrate; The method for producing a vapor-deposited phosphor layer according to claim 2, wherein the method is performed by relatively moving in a length direction perpendicular to the width direction of the phosphor layer.

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