X-ray fluorescence analyzer and X-ray aperture member

Abstract

In the present invention, an aperture member (1A) narrows the radiation range of primary X-rays generated in an X-ray tube (3). An analysis unit analyzes X-ray fluorescence generated from a sample by irradiating the sample with primary X-rays that have passed through the aperture member. The aperture member includes: a first opening (11A) formed on a primary X-ray incident side; a second opening (12A) formed on a primary X-ray exit side; and a hole (10A) that allows the primary X-rays to pass, and that is formed between the first opening and the second opening. If the direction from the center of the second opening toward an edge portion (14A), which is the corner of a peripheral portion (13A) of the second opening, is a first direction, the aperture member includes, in a hole inner surface (19A), a shielding portion (16A) that is formed between the X-ray tube and the peripheral portion of the second opening and that is formed more in the first direction than a straight line connecting the X-ray tube and the edge portion of the second opening.

Description

Technical Field

[0001] The present invention relates to a fluorescent X-ray analyzer and an X-ray aperture member.

Background Art

[0002] In Japanese Patent Application Laid-Open No. 2009-2795 (Patent Document 1), in a fluorescent X-ray analyzer, primary X-rays emitted from an X-ray tube are irradiated onto a sample, and fluorescent X-rays generated from the sample are detected by a detector, thereby performing qualitative and quantitative analysis of elements contained in the sample.

Prior Art Documents

Patent Documents

[0003]

Patent Document 1

Summary of the Invention

Problems to be Solved by the Invention

[0004] In a conventional fluorescent X-ray analyzer, a configuration is known in which the emission range of primary X-rays is narrowed by passing the primary X-rays emitted from an X-ray tube through an aperture member having a circular hole. The primary X-rays that have passed through the hole of this aperture member are irradiated onto the sample after further passing through, for example, a primary X-ray filter and a collimator lens.

[0005] However, the edge portion of the hole on the primary X-ray emission side in the aperture member is thinner in the thickness in the incident direction of the primary X-rays than other portions. Therefore, at the edge portion, there is a possibility that fluorescent X-rays from the aperture member generated by the incidence of the primary X-rays are mixed with the primary X-rays that have passed through the hole and irradiated onto the sample stage and detected by the detector. Thus, if the fluorescent X-rays from the aperture member are mixed with the primary X-rays, there is a risk of being detected as noise.

[0006] The present disclosure has been made to solve such problems, and an object thereof is to suppress the emission of fluorescent X-rays from a diaphragm member and reduce noise in a fluorescent X-ray analyzer.

Means for Solving the Problems

[0007] A first aspect of the present invention relates to a fluorescent X-ray analyzer. The fluorescent X-ray analyzer includes an X-ray tube, a diaphragm member, and an analysis unit. The diaphragm member narrows the irradiation range of the primary X-rays generated by the X-ray tube. The analysis unit analyzes fluorescent X-rays generated from a sample when the primary X-rays that have passed through the diaphragm member irradiate the sample. A first opening is formed on the incident side of the primary X-rays in the diaphragm member, a second opening is formed on the emission side of the primary X-rays, and a hole for passing the primary X-rays is formed between the first opening and the second opening. When the direction from the center of the second opening toward the end portion which is the corner of the edge portion of the second opening is defined as the first direction, the diaphragm member includes a shielding portion formed in the first direction on the inner surface of the hole, between the X-ray tube and the edge portion of the second opening and also closer to the first direction than the straight line connecting the X-ray tube and the end portion of the second opening.

[0008] A second aspect of the present invention relates to a diaphragm member. A first opening is formed on the incident side of X-rays in the diaphragm member, a second opening is formed on the emission side of X-rays, and a hole for passing X-rays is formed between the first opening and the second opening. When the direction from the center of the second opening toward the end portion which is the corner of the edge portion of the second opening is defined as the first direction, the diaphragm member includes a shielding portion formed in the first direction on the inner surface of the hole, between the X-ray source and the edge portion of the second opening and also closer to the first direction than the straight line connecting the X-ray source and the end portion of the second opening.

[0009] According to the present disclosure, the primary X-rays generated from the X-ray tube are shielded by the shielding portion formed on the inner surface of the hole of the diaphragm member, and the amount of incident primary X-rays on the edge portion of the second opening in the diaphragm member is reduced. Therefore, the generation of fluorescent X-rays due to the incidence of the primary X-rays on the edge portion is suppressed, and the possibility of irradiating the sample stage is reduced, so that noise can be reduced.

Brief Description of the Drawings

[0010]

Figure 1

Figure 2

Figure 3

Figure 4

Figure 5

Figure 6

Embodiments for Carrying Out the Invention

[0011] Hereinafter, embodiments of the present invention will be described in detail with reference to the drawings. In the drawings, the same or corresponding parts are denoted by the same reference numerals and their description will not be repeated.

[0012] [1. Configuration of Fluorescent X-ray Analyzer] FIG. 1 is a schematic diagram showing the configuration of an analyzer 100 according to an embodiment of the present invention. Referring to FIG. 1, the analyzer 100 is a fluorescent X-ray analyzer. The analyzer 100 includes a main body 8 and a processing device 9.

[0013] The main body 8 includes a housing 83, a housing 91, and a sample stage 81. The housing 83 is installed on the upper surface of the sample stage 81. The sample chamber 80 is formed by the housing 83 and the sample stage 81. The housing 91 is installed on the lower surface of the sample stage 81. The measurement chamber 90 is formed by the housing 91 and the sample stage 81. The sample chamber 80 and the measurement chamber 90 are hermetically surrounded by the housing 83 and the housing 91.

[0014] An opening 82 is formed in the sample stage 81, and a sample S is placed on the sample stage 81 so as to cover the opening 82. At the time of measurement, the sample S is placed on the sample stage 81 so that the measurement position of the sample S is exposed to the measurement chamber 90 at the opening 82.

[0015] In the measurement chamber 90, a diaphragm member 1, an X-ray tube 3, a housing 91, a shutter 93, a filter 94, a collimator 95, a drive mechanism 96, a detector 97, and an imaging unit 98 are arranged.

[0016] The X-ray tube 3 and the detector 97 are installed on the wall surface of the measurement chamber 90. The X-ray tube 3 has a filament that emits thermoelectrons and a target that converts the thermoelectrons into predetermined primary X-rays and emits them. The primary X-rays emitted from the X-ray tube 3 are irradiated onto the measurement position of the sample S through the opening 82. The secondary X-rays (fluorescent X-rays) generated from the sample S enter the detector 97, and the detector 97 measures the energy and intensity of the fluorescent X-rays. In the optical path of the primary X-rays from the X-ray tube 3 to the sample S, the diaphragm member 1, the shutter 93, the filter 94, and the collimator 95 are arranged in this order. The shutter 93, the filter 94, and the collimator 95 are configured to be slidable by the drive mechanism 96.

[0017] The diaphragm member 1 narrows the emission range of the primary X-rays emitted from the X-ray tube 3. The primary X-rays with the emission range narrowed by the diaphragm member 1 enter the filter 94.

[0018] The filter 94 is formed of a metal foil selected according to the purpose, and is a primary X-ray filter that attenuates the background component of the primary X-rays emitted from the X-ray tube 3 and improves the S / N ratio of the necessary characteristic X-rays. In one example, the filter 94 is composed of a plurality of filters formed of different types of metals, and the filter selected according to the purpose is inserted into the optical path of the primary X-rays by the drive mechanism 96. The primary X-rays that have passed through the filter 94 enter the collimator 95.

[0019] The collimator 95 has a circular opening at the center and determines the size of the primary X-ray beam that irradiates the sample S. The collimator 95 is formed of an X-ray absorber such as lead or brass. In one example, the collimator 95 is composed of, for example, a plurality of collimators with different aperture diameters, and the collimator selected according to the purpose is inserted onto the primary X-ray beam line by the drive mechanism 96. The primary X-ray beam that has passed through the collimator 95 is irradiated onto the sample S.

[0020] The shutter 93 is formed of an X-ray absorber such as lead and can be inserted into the optical path of the primary X-ray to shield the primary X-ray when it is necessary to shield the primary X-ray.

[0021] The imaging unit 98 is installed at the lower part of the measurement chamber 90. The imaging unit 98 images the measurement position of the sample S through the opening 82 formed in the sample stage 81. The imaging unit 98 includes an image sensor partitioned into a plurality of pixels, such as a CMOS (Complementary Metal Oxide Semiconductor) or a CCD (Charge Coupled Device), for example. A measurement operator performing fluorescence X-ray analysis can, before measurement, display the image acquired by this imaging unit 98 on a display device (not shown) and adjust the measurement position of the sample S while viewing this image.

[0022] The processing device 9 includes a CPU (Central Processing Unit) which is an arithmetic processing unit. For the processing device 9, for example, a personal computer or the like can be used. The X-ray tube 3, the detector 97, and the imaging unit 98 are connected to the processing device 9.

[0023] The processing device 9 controls the measurement by the main body 8. Specifically, the processing device 9 controls the tube voltage, tube current, irradiation time, etc. in the X-ray tube 3, and drives each of the shutter 93, the filter 94, and the collimator 95.

[0024] During measurement, the processing device 9 acquires the spectrum of the fluorescent X-rays detected by the detector 97. The processing device 9 performs quantitative analysis of each element based on the spectrum of the fluorescent X-rays detected by the detector 97. In the spectrum of the fluorescent X-rays, peaks of the fluorescent X-rays appear at energy positions specific to each element. Therefore, by examining the peak positions of the spectrum of the fluorescent X-rays, the elements contained in the sample S can be identified.

[0025] [2. Diaphragm member according to the present embodiment] FIG. 2 is a cross-sectional view of a diaphragm member 1A, which is an example of the diaphragm member 1 according to the embodiment of the present invention. Referring to FIG. 2, in the diaphragm member 1A, a first opening 11A is formed on the incident side of the primary X-rays, and a second opening 12A is formed on the exit side of the primary X-rays. Further, a hole 10A for passing the primary X-rays is formed between the first opening 11A and the second opening 12A.

[0026] In this specification, the central axis 4 of the emission range of the primary X-rays is defined as the X-axis, and the positive direction of the X-axis is defined as the emission direction. Further, the direction from the central axis 4 toward the inner surface 19A of the hole 10A is referred to as the "outer side (or first direction)". Conversely, the direction from the inner surface 19A of the hole 10A toward the central axis 4 is referred to as the "inner side (or second direction)".

[0027] Arrow 21 indicates the emission range of the primary X-rays narrowed by the second opening 12A of the diaphragm member 1A. Arrow 22A indicates the traveling direction of the primary X-rays emitted slightly outside the emission range.

[0028] More specifically, in the diaphragm member 1A, each of the first opening 11A and the second opening 12A has a circular shape. The diameter of the second opening 12A is larger than the diameter of the first opening 11A. The inner surface 19A of the hole 10A is formed in a two-step stepped shape. The corner of the step portion between the first opening 11A and the second opening 12A is formed between the X-ray tube 3 and the edge portion 13A of the second opening 12A, and corresponds to a shielding portion 16A described later.

[0029] [3. Comparison with a diaphragm member according to a comparative example] FIG. 3 is a cross-sectional view of the aperture member 1Q according to the comparative example. Referring to FIG. 3, the aperture member 1Q is formed such that a cylindrical hole 10Q penetrates the center of the cylinder. The opening on the incident side of the primary X-ray of the aperture member 1Q is referred to as the first opening 11Q, and the opening on the emission side is referred to as the second opening 12Q.

[0030] The emission range of the primary X-ray narrowed by the aperture member 1Q is indicated by an arrow 21. As shown by the arrow 21, the emission range of the primary X-ray emitted from the X-ray tube 3 is narrowed to the range inside the straight line connecting the X-ray tube 3 and the end 14Q of the second opening 12Q by the aperture member 1Q The end 14Q is the corner of the edge 13Q of the second opening 12Q. More specifically, the end 14Q indicates the vertex of the corner of the edge 13Q.

[0031] When the aperture member 1Q is used, among the primary X-rays emitted from the X-ray tube 3, the X-rays inside the arrow 21 pass through the aperture member 1Q. On the other hand, among the primary X-rays emitted from the X-ray tube 3, the X-rays outside the arrow 21 are shielded by the aperture member 1Q.

[0032] An arrow 22Q indicates the traveling direction of the primary X-ray emitted slightly outside the arrow 21. The primary X-ray traveling in the direction of the arrow 22Q is incident on the edge 13Q of the second opening 12Q. The edge 13Q is a portion included in the range having a predetermined distance from the end 14Q. Here, at the edge 13Q, the thickness in the direction of the arrow 22Q is relatively thinner than the thickness in the traveling direction of the primary X-ray in other portions of the aperture member 1Q. Therefore, at the edge 13Q, the fluorescent X-ray generated by the incidence of the primary X-ray may be emitted from the edge 13Q, irradiate the sample stage, and be detected by the detector 97. Thus, the fluorescent X-ray generated at the edge 13Q of the aperture member 1Q may be mixed with the primary X-ray emitted from the second opening 12Q, and the fluorescent X-ray component of the aperture member 1Q may be detected as noise in the analysis result.

[0033] Therefore, in the analyzer 100 according to the present embodiment, a shielding portion is formed between the X-ray tube 3 and the edge portion (the shaded portion 15Q in FIG. 3) inside the hole of the aperture member 1. As a result, in the aperture member 1A, the primary X-rays traveling in the direction of arrow 22A generated from the X-ray tube 3 are shielded by the shielding portion 16A and do not enter the edge portion 13A. Therefore, it is possible to reduce the noise generated when the fluorescent X-rays generated by the edge portion 13A irradiate the sample stage 81.

[0034] Note that the fluorescent X-rays generated by the primary X-rays incident on the shielding portion 16A are shielded on the inner surface 19A as indicated by the arrow 23A, so the possibility of being detected as noise by the detector 97 is low.

[0035] Further, the shielding portion 16A is formed outside a straight line connecting the X-ray tube 3 and the end portion 14A of the second opening 12A. That is, the shielding portion 16A is formed outside the arrow 21. Therefore, the shielding portion 16A does not narrow the irradiation range of the primary X-rays defined by the second opening 12A.

[0036] The aperture member 1A may be formed, for example, by combining a plurality of components. The aperture member 1A may be formed, for example, by overlapping and joining two members 1A1 and 1A2. In this case, the diameter of the hole formed in the member 1A1 corresponds to the diameter of the first opening 11A. Also, the diameter of the hole formed in the member 1A2 corresponds to the diameter of the second opening 12A. In this case, since it is only necessary to form holes with two different diameters in two members of the same shape and join them, the manufacturing cost can be suppressed. Alternatively, the aperture member 1A may be integrally formed. In this case, a hole with a diameter corresponding to the first opening 11A is formed in the material of the aperture member 1A, and then a hole with a diameter corresponding to the second opening 12A is formed up to the middle in the thickness direction to form a stepped portion.

[0037] The aperture member 1A is formed of, for example, brass or tungsten. When brass is used, the unit price of the aperture member 1A can be kept low. When tungsten is used, it is more expensive than brass, but the shielding effect of the primary X-rays in the portion other than the hole 10A in the aperture member 1A becomes higher.

[0038] In the aperture member 1A, between the surface (lower surface) 17A in the negative direction of the X-axis and the surface (upper surface) 18A in the positive direction of the X-axis, it is solid in the portion other than the hole 10A between the first opening 11A and the second opening 12A. Therefore, in the aperture member 1A, the shielding effect of the primary X-rays in the portion other than the hole 10A is greater than when the portion between the surface 17A and the surface 18A is hollow in the portion other than the hole 10A. Specifically, in the aperture member 1, the effect of preventing the leakage of the primary X-rays from between the surface 17A and the surface 18A to the outside becomes greater. Also, in the aperture member 1A, the effect of suppressing the leakage of the primary X-rays in the positive direction of the X-axis in the portion other than the hole 10A becomes greater.

[0039] As described above, the aperture member according to the present embodiment suppresses the incidence of the primary X-rays on the edge portion of the second opening by the shielding portion formed on the inner surface of the hole. Therefore, the fluorescent X-rays generated from the edge portion of the aperture member can be suppressed, and the possibility of being irradiated to the sample stage can be reduced, so that the noise in the analysis result can be reduced.

[0040] Also, by providing the shielding portion before the primary X-rays enter the edge portion, the thickness in the traveling direction of the primary X-rays can be increased, so that the amount of the primary X-rays passing through the edge portion can be reduced.

[0041] [4. Modification Example] Note that the configuration of the aperture member 1 according to the present embodiment is not limited to the example in FIG. 2, and the shielding portion may be formed between the X-ray tube 3 and the edge portion of the second opening, and the shielding portion may be formed outside with respect to the straight line connecting the X-ray tube and the end portion of the second opening in the passing direction of the primary X-rays.

[0042] (Modification Example 1) For example, the inner surface of the aperture member 1 may be formed in a stepped shape with three or more steps as shown in FIG. 4. In this case, the shielding portion may be at least one corner portion of the stepped portion between the first opening 11B and the second opening 12B. In the aperture member 1B of FIG. 4, for example, the first corner portion from the first opening 11B is the shielding portion 16B. The aperture member 1B is formed, for example, by overlapping and joining disks in which three different holes are formed.

[0043] By configuring the aperture member 1 in multiple stages like the aperture member 1B, it is easier to form a solid between the arrow 21 and the inner surface 19A compared to the case of FIG. 2. That is, between the arrow 21 and the inner surface 19A, the space portion is reduced, and the proportion occupied inside the aperture member 1 increases. Therefore, the shielding effect of the primary X-rays emitted outside the arrow 21, represented by the arrow 22B, becomes greater.

[0044] (Modification Example 2) Also, the diameter of the second opening of the aperture member 1 does not necessarily have to be larger than the diameter of the first opening. That is, as shown in FIG. 5, the diameter of the second opening may be equal to or smaller than the diameter of the first opening. Referring to FIG. 5, in the aperture member 1C, the diameter of the second opening 12C is equal to the diameter of the first opening 11C. For this reason, for example, when installing the aperture member 1C in the analyzer 100, the same effect is achieved regardless of whether the first opening of the aperture member 1C is arranged in the positive or negative direction of the X-axis.

[0045] (Modification Example 3) Furthermore, as shown in FIG. 6, the inner surface of the aperture member 1 may be tapered. Referring to FIG. 6, the first opening 11D and the second opening 12D of the aperture member 1D are circular. The inner surface 19D of the hole 10D formed between the first opening 11D and the second opening 12D is formed in a tapered shape. The diameter of the hole 10D increases in a tapered shape from the first opening 11D to the second opening 12D. In the aperture member 1D, the portion along the inner surface 19D is the shielding portion 16D. The arrow 22D is the primary X-ray emitted slightly outside the arrow 21, similar to the arrow 22Q. The shielding portion 16D shields the primary X-ray indicated by the arrow 22D. On the other hand, the space between the arrow 21 and the inner surface 19D becomes solid compared to the case of FIG. 2. That is, in the space between the arrow 21 and the inner surface 19D, the space portion is reduced, and the proportion occupied inside the aperture member 1 increases. Therefore, the shielding effect of the primary X-ray emitted outside the arrow 21, as represented by the arrow 22D, becomes greater.

[0046] Also, the configuration of the aperture member 1 according to the present embodiment is not limited to the aperture of the primary X-ray emitted from the X-ray tube 3 in the above-described fluorescent X-ray analyzer, and may be applied to other X-ray aperture structures. For example, the configuration of the aperture member 1 according to the present embodiment may be applied to a collimator. Further, when the fluorescent X-ray analyzer includes an aperture member for the fluorescent X-ray generated at the sample stage, the configuration of the aperture member 1 according to the present embodiment may be applied to the aperture member. In this case, the sample placed on the sample stage corresponds to an example of an "X-ray source". Furthermore, it may be applied to an X-ray aperture member in other devices that use X-rays. In this case, the object that emits X-rays to the aperture member corresponds to an example of an "X-ray source".

[0047] Note that the shape of the hole when the aperture member 1 is viewed in a plan view from the X-ray emission direction (X-axis direction) is not limited to a circular shape, and may be other shapes such as a polygon or an ellipse according to the application or convenience during manufacturing.

[0048] [Aspect] Those skilled in the art will understand that the above-described plurality of exemplary embodiments are specific examples of the following aspects.

[0049] (1) A fluorescent X-ray analyzer according to one aspect includes an X-ray tube, a diaphragm member, and an analysis unit. The diaphragm member narrows the irradiation range of the primary X-rays generated by the X-ray tube. The analysis unit analyzes the fluorescent X-rays generated from the sample when the primary X-rays passing through the diaphragm member irradiate the sample. In the diaphragm member, a first opening is formed on the incident side of the primary X-rays, a second opening is formed on the exit side of the primary X-rays, and a hole for passing the primary X-rays is formed between the first opening and the second opening. When the direction from the center of the second opening toward an end portion which is a corner of the edge portion of the second opening is defined as a first direction, the diaphragm member includes, on the inner surface of the hole, a shielding portion formed in the first direction between the X-ray tube and the edge portion of the second opening and also closer to the first direction than a straight line connecting the X-ray tube and the end portion of the second opening.

[0050] According to the fluorescent X-ray analyzer described in (1), the primary X-rays generated from the X-ray tube are shielded by the shielding portion formed on the inner surface of the hole of the diaphragm member, and the amount of the primary X-rays incident on the edge portion of the second opening in the diaphragm member is reduced. Therefore, the generation of fluorescent X-rays due to the incidence of the primary X-rays on the edge portion is suppressed, and the possibility of irradiating the sample stage is reduced, so that noise can be reduced.

[0051] (2) In the fluorescent X-ray analyzer described in (1), each of the first opening and the second opening has a circular shape. The inner surface of the hole is formed in a two-step stepped shape. The diameter of the second opening is larger than the diameter of the first opening. The shielding portion is a corner portion of a stepped portion between the first opening and the second opening.

[0052] The diaphragm member in the fluorescent X-ray analyzer described in (2) can be formed by forming holes with two different diameters in two members having the same shape and joining them. Alternatively, it can be formed by forming a hole with a diameter corresponding to the first opening in the material of the diaphragm member and then forming a hole with a diameter corresponding to the second opening up to the middle in the thickness direction. That is, the diaphragm member is easy to form and the manufacturing cost can be suppressed.

[0053] (Item 3) In the fluorescent X-ray analyzer according to Item 1, each of the first opening and the second opening has a circular shape. The inner surface of the hole is formed in a stepped shape with three or more steps. The diameter of the hole increases stepwise from the first opening to the second opening. The shielding portion is at least one corner portion of the stepped portion between the first opening and the second opening.

[0054] In the aperture member of the fluorescent X-ray analyzer according to Item 3, it is easier to form solidly between the straight line connecting the X-ray tube and the end portion and the inner surface of the hole than when the inner surface of the hole is formed in a stepped shape with two steps. That is, the shielding effect of the primary X-rays emitted outside the straight line connecting the X-ray tube and the end portion is increased.

[0055] (Item 4) In the fluorescent X-ray analyzer according to Item 1, each of the first opening and the second opening has a circular shape. The inner surface of the hole is formed in a tapered shape. The diameter of the hole increases in a tapered shape from the first opening to the second opening.

[0056] In the aperture member of the fluorescent X-ray analyzer according to Item 4, it is solid between the straight line connecting the X-ray tube and the end portion and the inner surface of the hole than when the inner surface of the hole is formed in a stepped shape with two steps. That is, the shielding effect of the primary X-rays emitted outside the straight line connecting the X-ray tube and the end portion is increased.

[0057] (Item 5) In the aperture member of the fluorescent X-ray analyzer according to any one of Items 1 to 4, it may be solid between the surface on the incident side of the primary X-rays and the surface on the emission side of the primary X-rays.

[0058] According to the fluorescent X-ray analyzer according to Item 5, in the aperture member, the shielding effect of the primary X-rays in the portion other than the hole is greater than when the portion between the surface on the incident side (lower surface) of the primary X-rays and the surface on the emission side (upper surface) of the primary X-rays in the portion other than the hole is hollow. Specifically, in the aperture member according to Item 5, the effect of preventing the leakage of the primary X-rays from the portion between the lower surface and the upper surface to the outside is increased. Also, in the aperture member, the effect of suppressing the leakage of the primary X-rays in the positive direction of the X-axis in the portion other than the hole is increased.

[0059] (Item 6) The aperture member according to one aspect is an aperture member for narrowing the X-ray irradiation range. In the aperture member, a first opening is formed on the X-ray incident side, a second opening is formed on the X-ray exit side, and a hole for passing X-rays is formed between the first opening and the second opening. When the direction from the center of the second opening to an end which is a corner of the edge portion of the second opening is defined as the first direction, the aperture member includes a shielding portion formed on the inner surface of the hole, between the X-ray source and the edge portion of the second opening, and in the first direction rather than the straight line connecting the X-ray source and the end of the second opening.

[0060] According to the fluorescent X-ray analyzer described in Item 6, the primary X-rays generated from the X-ray source are shielded by the shielding portion formed on the inner surface of the hole of the aperture member, and the incident amount of the primary X-rays on the edge portion of the second opening in the aperture member is reduced. Therefore, the generation of fluorescent X-rays due to the incidence of the primary X-rays on the edge portion is suppressed.

[0061] It should be considered that the embodiments disclosed this time are illustrative in all respects and not restrictive. The scope of the present invention is shown not by the above description but by the claims, and it is intended that all modifications within the meaning and scope equivalent to the claims are included.

Explanation of Reference Numerals

[0062] 1, 1A, 1B, 1C, 1D, 1Q aperture member, 1A1, 1A2 disk, 3 X-ray tube, 8 main body, 9 processing device, 10A to 10D, 10Q hole, 11A to 11D, 11Q first opening, 12A to 12D, 12Q second opening, 13A to 13D, 13Q edge portion, 14A to 14D, 14Q end, 15Q hatched portion, 16A to 16D, 16Q shielding portion, 17A to 17D, 17Q, 18A to 18D, 18Q surface, 19A to 19D, 19Q inner surface, 80 sample chamber, 81 sample stage, 82 opening, 83, 91 housing, 90 measurement chamber, 92 joint portion, 93 shutter, 94 filter, 95 collimator, 96 drive mechanism, 97 detector, 98 imaging unit, 100 analyzer, S sample.

Claims

1. an X-ray tube, a diaphragm member for narrowing the irradiation range of the primary X-rays generated by the X-ray tube, and an analysis unit that analyzes fluorescent X-rays generated from a sample when the primary X-rays that have passed through the diaphragm member are irradiated onto the sample, wherein the diaphragm member has, a first opening having a circular shape on the incident side of the primary X-rays, a second opening having a circular shape on the emission side of the primary X-rays, a hole for passing the primary X-rays is formed between the first opening and the second opening, the emission port of the X-ray tube is smaller than the diameter of the hole at the portion where the diameter of the hole in the diaphragm member is the smallest, when a direction from the center of the second opening toward an end portion that is a corner of the edge portion of the second opening is defined as a first direction, the diaphragm member includes a shielding portion formed in the first direction from a straight line connecting the X-ray tube and the end portion of the second opening, between the X-ray tube and the edge portion of the second opening, on the inner surface of the hole, a fluorescent X-ray analyzer.

2. The inner surface of the hole is formed in a two-step stepped shape, the diameter of the second opening is larger than the diameter of the first opening, the shielding portion is a corner portion of a stepped portion between the first opening and the second opening, the fluorescent X-ray analyzer according to claim 1.

3. The inner surface of the hole is formed in a stepped shape of three or more steps, the diameter of the hole increases stepwise from the first opening to the second opening, the shielding portion is at least one corner portion of a stepped portion between the first opening and the second opening, the fluorescent X-ray analyzer according to claim 1.

4. The inner surface of the hole is formed in a tapered shape, the diameter of the hole increases in a tapered shape from the first opening to the second opening, the fluorescent X-ray analyzer according to claim 1.

5. in the diaphragm member, the portion between the surface on the incident side of the primary X-rays and the surface on the emission side of the primary X-rays is solid, the fluorescent X-ray analyzer according to claim 1.

6. A diaphragm member for narrowing the irradiation range of X-rays irradiated from an X-ray tube, wherein the diaphragm member has, a first opening having a circular shape on the incident side of the X-rays, a second opening having a circular shape on the emission side of the X-rays, a hole for passing the X-rays is formed between the first opening and the second opening, the emission port of the X-ray tube is smaller than the diameter of the hole at the portion where the diameter of the hole in the diaphragm member is the smallest, When a direction from the center of the second opening toward an end portion which is a corner of an edge portion of the second opening is defined as a first direction, the aperture member is an aperture member including a shielding portion formed in a first direction from a straight line connecting the X-ray tube and the end portion of the second opening and located between the X-ray tube and the edge portion of the second opening on an inner surface of the hole.

Images