X-ray radiation generation device and X-ray analysis device

Abstract

X-ray generating device (11), comprising: a sealed X-ray tube (31) with a cathode (41) from which thermionic electrons are emitted and an anode (42) which is irradiated with an electron beam obtained by accelerating the thermionic electrons with a potential difference applied between the cathode (41) and the anode (42); a magnetic field generating section (32) arranged near the sealed X-ray tube (31) to apply a magnetic field to the electron beam, the magnetic field extending in a first direction that intersects a propagation direction of the electron beam; and a rotary drive system (33) designed to rotate the sealed X-ray tube (31) with respect to a central axis of the cathode (41) and the anode (42), wherein the anode (42) has a surface with a first region and a second region, which are arranged on one side and another side respectively with respect to a straight dividing line passing through an intersection of the surface and the central axis; wherein the first region comprises a first metal arranged therein and the second region comprises a second metal arranged therein, wherein the second metal differs from the first metal, wherein the sealed X-ray tube (31) is driven by the rotary drive system (33) to a position in which the sealed X-ray tube (31) is arranged with respect to the magnetic field generating section (32) such that the straight dividing line which separates the first anode region from the second anode region lies along the first direction of the magnetic field.

Description

Technical field

[0001] The present invention relates to an X-ray generation device comprising a sealed X-ray tube and an X-ray analysis unit. The present invention particularly relates to a technology for the selective generation of X-rays of different wavelengths with a simple design. State of the art

[0002] Up to now, the following X-ray sources have been used in X-ray analysis systems to select an X-ray beam from a multitude of X-rays with different wavelengths for analysis. In a first X-ray source, a sealed X-ray tube is selectively placed. In a second X-ray source, several sealed X-ray tubes are arranged, each designed to generate X-rays with different wavelengths; and the multiple sealed X-ray tubes are selectively driven. In a third X-ray source, a sealed X-ray tube contains two systems (two sets of a cathode and an anode), and one of the cathodes (filaments) to be heated (with an applied voltage) is selected to generate a desired X-ray beam (see patent reference 1).In a fourth X-ray source, an anode is a rotor target (a target with a rotating anticathode), and several different metals are arranged on a surface of the rotor target and moved along a rotational axis to select a metal to be irradiated and thus to generate a desired X-ray radiation (see patent references 2 to 7). Furthermore, patent reference 8 discloses an X-ray source designed to generate pulsed X-ray radiation, wherein the electron beam is deflected from a peripheral target area (W-target) to a central target area (Cu-target) with each pulse. This suppresses the generation of soft X-ray radiation. Reference list of patent literature [PTL 1] JP 2007-323964 A [PTL 2] JP 2008-269933 A [PTL 3] WO 2016 / 039 091 A1 [PTL 4] WO 2016 / 039 092 A1 [PTL 5] DE 31 17 726 A1 [PTL 6] US 3 229 089 A [PTL 7] US 2011 / 0 133 094 A1 [PTL 8] JP 2010 - 198 778 A Brief description of the invention: Technical problem

[0003] Over the past few years, there has been a requirement for an X-ray analysis system to miniaturize the system, in addition to selecting an X-ray beam from a variety of X-ray beams with different wavelengths for analysis, and it is desirable to miniaturize a sealed X-ray tube to serve as the X-ray source.

[0004] In the first X-ray source mentioned above, the sealed X-ray tube itself can be achieved with a simple design, although it is necessary to manufacture several sealed X-ray tubes. Furthermore, each time one of the X-ray beams with a different wavelength is selected, the sealed X-ray tube must be replaced with one designed to emit X-rays of the corresponding wavelength, which increases the time required for the measurement.

[0005] In the second and third X-ray sources mentioned above, the focus positions of the X-rays with different wavelengths are different, and a motion control system is required to ensure that the X-rays with different wavelengths have the same focus position. In the second X-ray source, the positions of the sealed X-ray tubes must be moved to align the optical axis of an X-ray beam. In the third X-ray source, a sealed X-ray tube is moved to align the position of an anode of interest. Additionally, the setup is larger in both the second and third X-ray sources. In the second X-ray source, reducing the focal point of a generating source is particularly challenging.

[0006] The fourth X-ray source mentioned above has a larger size and a more complex structure; for example, cooling of the rotor target is required. Therefore, the fourth X-ray source is unsuitable for miniaturizing the system and the X-ray source itself.

[0007] The present invention was made with regard to the problems mentioned above and therefore aims to provide an X-ray generation device capable of selectively generating an X-ray beam from a plurality of X-ray beams with different wavelengths in a simple design, and an X-ray analysis device. Solution to the problem To solve the problems mentioned above, an X-ray generating device according to the present invention comprises: a sealed X-ray tube with a cathode from which thermionic electrons are emitted and an anode which is irradiated with an electron beam obtained by accelerating the thermionic electrons using a potential difference applied between the cathode and the anode; a magnetic field generating section arranged near the sealed X-ray tube to apply a magnetic field to the electron beam, the magnetic field extending in a first direction which intersects a propagation direction of the electron beam; and a rotary drive system configured to rotate the sealed X-ray tube with respect to a central axis of the cathode and the anode, the anode having a surface with a first region and a second region, each having a first region on one side and a second region on the other.are arranged on another side with respect to a straight dividing line passing through an intersection of the surface with the central axis; wherein the first region has a first metal arranged therein and the second region has a second metal arranged therein, the second metal being different from the first metal, wherein the sealed X-ray tube is driven by the rotary drive system to a position in which the sealed X-ray tube is arranged with respect to the magnetic field generating section such that the straight dividing line separating the first anode region from the second anode region lies along the first direction of the magnetic field. In the X-ray generating device according to point (1) mentioned above, the electron beam can have a cross-section with an extending flat shape, and when the sealed X-ray tube is driven, the sealed X-ray tube can be arranged in relation to the magnetic field generating section such that one extension direction of the extending flat shape lies along the first direction. In the X-ray generating device according to point (1) or (2) above, the magnetic field generating section may be a permanent magnet. In the X-ray generating device according to any of the above points (1) to (3), the surface of the anode may have a circular shape and the intersection of the surface with the central axis may substantially coincide with a center of the circular shape. In the X-ray generating device according to one of the above points (1) to (4), the first direction can be substantially orthogonal to the direction of motion of the electron beam. In the X-ray generating device according to any of the above points (1) to (5), the sealed X-ray tube may include a first X-ray window and a second X-ray window, wherein the first X-ray window is configured to allow an X-ray beam generated from a first irradiation area in which the first metal arranged in the first area is irradiated with the electron beam to pass through, and wherein the second X-ray window is configured to allow an X-ray beam generated from a second irradiation area in which the second metal arranged in the second area is irradiated with the electron beam to pass through.

[0008] In the X-ray generating device according to one of the above points (1) to (6), the filament of the cathode may be provided on the central axis and the longitudinal direction of the cathode may be along the straight dividing line.

[0009] (8) An X-ray analysis device according to the present invention may include: the X-ray generating device according to any of the above points (1) to (6); a support base configured to support a sample which is to be irradiated with an X-ray beam emitted by the X-ray generating device; and a detector configured to detect scattered X-rays produced by the sample. Advantageous effects of the invention

[0010] According to the present invention, the X-ray generation device, which is capable of selectively generating an X-ray beam from a plurality of X-ray beams with different wavelengths in a simple design, and the X-ray analysis device are provided. Brief description of the drawings Fig. Figure 1 is a schematic diagram illustrating an embodiment of an X-ray analysis device according to an embodiment of the present invention. Fig. Figure 2A is a view illustrating a principle of a sealed X-ray tube in the embodiment of the present invention. Fig. Figure 2B is a view illustrating an arrangement of a cathode and an anode of the sealed X-ray tube in the embodiment of the present invention. Fig. Figure 2C is a top view of the anode in the embodiment of the present invention. Fig. Figure 3A is a schematic view to illustrate an embodiment of an X-ray source section in the embodiment of the present invention. Fig. Figure 3B is a schematic view to illustrate the design of the X-ray source section in the embodiment of the present invention. Fig. Figure 3C is a schematic view to illustrate the design of the X-ray source section in the embodiment of the present invention. Fig. 3D is a schematic view to illustrate the design of the X-ray source section in the embodiment of the present invention. Fig. Figure 4A is a schematic view illustrating an embodiment of an X-ray source section in an alternative embodiment 1. Fig. Figure 4B is a schematic view illustrating the design of the X-ray source section in alternative embodiment 1. Fig. Figure 5A is a schematic view illustrating an embodiment of an X-ray source section in an alternative embodiment 2. Fig. Figure 5B is a schematic view illustrating the design of the X-ray source section in alternative embodiment 2. Fig. Figure 6A is a schematic view illustrating an embodiment of an X-ray source section in an alternative embodiment 3. Fig. Figure 6B is a schematic view illustrating the design of the X-ray source section in alternative embodiment 3. Description of embodiments

[0011] An embodiment of the present invention will now be described with reference to the drawings. For clarity, some sizes, shapes, and the like are shown schematically in the drawings in comparison to actual dimensions. However, these sizes, shapes, and the like are only examples and do not limit the understanding of the present invention. Furthermore, elements identical to those described and relating to the aforementioned drawings are designated by the same reference symbols here and in each of the drawings, and a detailed description thereof is sometimes omitted where appropriate.

[0012] Fig. Figure 1 is a schematic diagram illustrating an embodiment of an X-ray analysis device 1 according to an embodiment of the present invention. In this example, the X-ray analysis device 1 according to this embodiment is an X-ray diffraction (XRD) measuring device. However, the X-ray analysis device 1 can also be, among other things, a small-angle X-ray scattering (SAXS) measuring device or another type of X-ray analysis device. The X-ray analysis device 1 according to this embodiment includes an X-ray source section 11, an optical system 12, a support base 14 configured to hold a sample 100, a two-dimensional detector 15, and a goniometer 21.

[0013] The goniometer 21 is a horizontal sample-holding θ-θ goniometer. The goniometer 21 comprises an incident-side arm 21A, a mounting section 21B, and a light-receiving-side arm 21C. The X-ray source section 11 and the optical system 12 are arranged on the incident-side arm 21A, the support base 14 is arranged on the mounting section 21B, and the two-dimensional detector 15 is mounted on the light-receiving-side arm 21C. The goniometer 21 can perform a 2θ scan while holding the sample 100, which is supported on the support base 14, horizontally. By mounting the sample 100 horizontally, the distortion effect caused by the weight of the sample 100 itself can be minimized, and the risk of the sample 100 falling is suppressed.If the mounting section 21B (support base 14) in the goniometer 21 is rotated by an angle of θ with respect to the incident-side arm 21A (X-ray source section 11), the light-receiving-side arm 21C (two-dimensional detector 15) is rotated by an angle of 2θ with respect to the incident-side arm 21A.

[0014] The X-ray source section 11 is an X-ray generating device according to this embodiment and includes a sealed X-ray tube 31. Details of the X-ray source section 11 are described later. The optical system 12 consists, for example, of one or more slots. The support base 14, designed to hold the sample 100, is fixedly arranged on the mounting section 21B. X-rays generated by the X-ray source section 11 are shaped by the optical system 12 into a desired X-ray beam, and the sample 100, held by the support base 14, is irradiated with the X-ray beam.

[0015] The two-dimensional detector 15 is designed to detect scattered X-rays generated by the sample 100. The scattered X-rays comprise diffracted X-rays produced by the sample 100. Furthermore, in this embodiment, the detector is not limited to a two-dimensional detector and can be a one-dimensional detector. In addition, a light-receiving slit or other light-receiving optical system can be arranged between the support base 14 and the two-dimensional detector 15.

[0016] Fig. Figure 2A is a view illustrating one principle of the sealed X-ray tube 31 in this embodiment. The sealed X-ray tube 31 comprises a vacuum tube 40, a cathode 41, an anode 42, and an X-ray window 43. The cathode 41 and the anode 42 are arranged inside the vacuum tube 40, the interior being maintained at a vacuum, and the X-ray window 43 is arranged in a side face of the vacuum tube 40 (side face of the sealed X-ray tube 31).

[0017] Fig. Figure 2B is a view illustrating an arrangement of the cathode 41 and the anode 42 of the sealed X-ray tube 31 in this embodiment. Fig. 2B is a perspective view of a positional relationship between the cathode 41 and the anode 42. Fig. 2C is a top view of the anode 42 in this embodiment.

[0018] The cathode 41 contains a filament. A potential difference V FA potential difference of approximately a few V is applied across both ends of the filament when it is driven. When the filament is heated to approximately 2000°C, thermionic electrons are emitted from the cathode 41 (filament). In the driven state, a potential difference V of a few kV up to a few hundred kV is applied between the cathode 41 and the anode 42. In this embodiment, the distance between the cathode 41 and the anode 42 is approximately 6 mm, and the potential difference V to be applied between the cathode 41 and the anode 42 is approximately 30 kV. The thermionic electrons emitted from the cathode 41 are accelerated by the applied potential difference V, and the accelerated thermionic electrons form an electron beam that is directed (impacts) onto a surface of the anode 42. The filament of the cathode 41 has a linear shape, and the surface of the anode 42 has a circular shape.An irradiation region EB of the electron beam incident on the anode 42 has a linear shape (a rectangular shape in which one longitudinal direction is significantly larger than one transverse direction, referred to below as the "long rectangular shape") to match the filament shape of the cathode 41. In other words, the filament shape of the cathode 41 is the linear shape. When the potential difference V between the cathode 41 and the anode 42 is applied, the electric field is strongest in a region directly below the cathode when viewed from the anode 42. Therefore, most of the electrons are accelerated directly downwards along the electric field to form the electron beam that irradiates the irradiation region EB of the surface of the anode 42.In other words, a cross-section of the electron beam has a flat shape (which is essentially a linear shape or a long rectangular shape) that extends along a direction of extension of the linear shape of the filament. In each of . Fig. 2A to Fig. Figure 2C shows the x, y, and z axes. The z-axis represents the direction of propagation of the electron beam and runs parallel to the direction of the strongest electric field generated between the cathode 41 and the anode 42. The x-axis represents the direction of extension of the linear shape of the filament of the cathode 41. The y-axis is a direction perpendicular to both the x-axis and the z-axis.

[0019] When the electron beam is directed onto (strikes) the surface of the anode 42, X-rays are generated. Of the X-rays generated in several directions, those passing through the X-ray window 43 propagate towards the optical system 12. In other words, the sealed X-ray tube 31 emits the X-rays from the X-ray window 43. The irradiation area EB of the electron beam has a flat shape (essentially a linear or elongated rectangular shape) extending along the x-axis to match the linear shape of the filament of the cathode 41 and the flat cross-sectional shape of the electron beam. The thermionic electrons emitted from the cathode 41 are accelerated by the applied potential difference V (electric fields generated between the cathode 41 and the anode 42).When viewed from above along the z-axis, the cathode 41 appears as if contained within the anode 42. Therefore, when the anode 42 is viewed from the perspective of the cathode 41, the region directly beneath the cathode exhibits an electric field in the negative direction of the z-axis. However, the electric fields around this region have very small components (primarily along the y-axis) in the xy-plane. Consequently, the cross-section of the electron beam in the xy-plane (primarily along the y-axis) gradually spreads out compared to the linear shape of the cathode 41 filament as the electron beam propagates. Therefore, the irradiation region EB has a flat shape that spreads out compared to the linear shape of the cathode 41 filament (primarily along the y-axis).In the present application, the propagation direction of the electron beam is defined as a direction (in this example a z-direction) of the strongest electric field of the electric fields generated between the cathode 41 and the anode 42.

[0020] In a plane (xz-plane) that is orthogonal to a plane orthogonal to the surface (xy-plane) of the anode 42 and that contains an extension direction (x-axis) of the flat shape of the irradiation area EB, the X-ray window 43 is arranged on an extension in a direction that intersects the surface of the anode 42 (or the extension direction of the flat shape of the irradiation area EB) at a certain angle. By extracting the X-ray beam in an oblique direction from the flat irradiation area EB, the irradiation area EB at the anode 42 can, in effect, serve as a point-shaped X-ray source. Fig. 2A to Fig. Figure 2C shows the principle of the sealed X-ray tube 31 and illustrates a controlled state of the sealed X-ray tube 31 in a state in which no permanent magnet (described later) is located near the sealed X-ray tube 31.

[0021] Fig. 3A to Fig. 3D are schematic views to illustrate one configuration of the X-ray source section 11 in this embodiment. Fig. 3A shows a case of generating a first X-ray beam X1 and Fig. Figure 3B shows a case of generating a second X-ray beam X2. Fig. 3C is a top view of the anode 42 in the case of the generation of the first X-ray beam X1 and Fig. Figure 3D is a top view of the anode 42 in the case of the generation of the second X-ray beam X2. The X-ray source section 11 includes the sealed X-ray tube 31, a permanent magnet 32, and a rotary drive system 33. The sealed X-ray tube 31 in this embodiment is a simple X-ray tube, as described in Fig. Figure 2A shows no component configured for electrically or magnetically controlling the electron beam between the cathode 41 and the anode 42. In other words, for example, no alignment coil, deformation and rotation coil, or focusing coil is arranged inside or outside the sealed X-ray tube 31.

[0022] The sealed X-ray tube 31 in this embodiment has a structure that is rotationally symmetrical with respect to a central axis of the cathode 41 and the anode 42. The "central axis of the cathode 41 and the anode 42," as used here, refers to a straight line connecting the center of the cathode 41 (center of the linear shape of the filament) and the center of the anode 42 (center of the circular shape of the surface) and running parallel to the z-axis. The shape of the surface of the anode 42 is not limited to a circular shape; even in such a case, the central axis of the cathode 41 and the anode 42 is a perpendicular line drawn from the center of the cathode 41 to the anode 42. The outer diameter of the sealed X-ray tube 31 is 30 mm, and the anode 42 is a disk with an outer diameter of 10 mm and a thickness of 2 mm.

[0023] As in Fig. 3C and Fig. In this embodiment, the surface of the anode 42 has a circular shape, but the surface of the anode 42 is divided with respect to a straight division line DL (in this example, the diameter along the x-axis direction) that passes through a center O. In this example, the center O is an intersection between the central axis of the cathode 41 and the anode 42 with the surface of the anode 42 and is the center of the circular shape of the surface of the anode 42. On the surface of the anode 42, a first region and a second region are each located on one side (right side in ). Fig. 3C and left side in Fig. 3D) and the other side (left side in Fig. 3C and right side in Fig. 3D) of the straight dividing line DL. Furthermore, a first metal M1 is arranged in the first region and a second metal M2 is arranged in the second region. In this example, the first metal M1 and the second metal M2 are different metals. For example, the first metal M1 is tungsten (W) and the second metal M2 is copper (Cu). However, the present invention is not limited to this combination, and the first metal M1 and the second metal M2 can be either of two different metals suitable as anodes.

[0024] The permanent magnet 32 ​​is arranged near the sealed X-ray tube 31. In this embodiment, the permanent magnet 32 ​​is a magnetic field generating section. The permanent magnet 32 ​​is arranged and fixed independently of the sealed X-ray tube 31 such that a magnetic field is applied to the electron beam, extending in a first direction (in this example, the direction of the x-axis) and intersecting the propagation direction (in this example, the direction of the z-axis) of the electron beam. In this embodiment, it is desirable that a surface of the permanent magnet 32 ​​be located on the side of the sealed X-ray tube 31 at a position 15 mm to 18 mm from the central axis of the cathode 41 and the anode 42, and that the surface is, for example, located 2.5 mm from the side face of the vacuum tube 40 (side face of the sealed X-ray tube 31).When the permanent magnet 32 ​​applies the magnetic field extending in the first direction (in this example, in the positive direction of the x-axis) to the electron beam, a Lorentz force is exerted on the electron beam in a direction (in this example, in the positive direction of the y-axis) perpendicular to a plane formed by the propagation direction of the electron beam and the direction (first direction) of the magnetic field, in order to deflect the electron beam in this direction (in this example, the positive direction of the y-axis). Therefore, the irradiation area, in which the surface of the anode 42 is irradiated with the electron beam, is moved in this direction (in this example, the positive direction of the y-axis). In this embodiment, the deflection of the electron beam (the distance by which the irradiation area is moved from the center O) is in the range of 0.5 mm to 1 mm.The role of the permanent magnet 32 ​​is the same as that of a deflection coil in a cathode-ray oscilloscope with electromagnetic deflection. However, unlike the deflection coil, which is formed, for example, from a four-pole coil, the electron beam can be deflected with a very simple configuration in which the permanent magnet 32 ​​is arranged.

[0025] In this example, the permanent magnet 32 ​​is a toroidal neodymium magnet with an outer diameter of 15 mmφ and an inner diameter of 10 mmφ. The magnetic field extends linearly from a center of the neodymium magnet. In other words, the magnetic field penetrating the electron beam from a center of the permanent magnet 32 ​​(neodymium magnet) lies in the positive direction of the x-axis. Magnetic fields surrounding the magnetic field penetrating the electron beam from the center of the permanent magnet 32 ​​have very small components that propagate radially in a yz-plane. Therefore, the magnetic field penetrating the electron beam is not uniform in the strict sense, but these very small components have essentially no effect on the deflection of the electron beam for the purpose of deflecting the electron beam.From this perspective, it can be assumed that the permanent magnet 32 ​​applies the magnetic field extending in the first direction (positive direction of the x-axis) to the electron beam. The permanent magnet 32 ​​in this embodiment is the toroidal neodymium magnet, but it could be a neodymium magnet of a different shape or a permanent magnet made of a different material.

[0026] As in Fig. 3C and Fig. 3D can be achieved by using the rotary drive system 33, which rotates the sealed X-ray tube 31, allowing the sealed X-ray tube 31 to be positioned at a desired rotational position during operation. This applies both to the generation of the first X-ray beam X1, which is in Fig. 3A and Fig. 3C is illustrated, and in the case of the generation of the second X-ray beam X2, which is in Fig. 3B and Fig. As illustrated in 3D, the sealed X-ray tube 31 is arranged relative to the permanent magnet 32 ​​such that the straight dividing line DL of the anode 42 lies along the direction (first direction) of the magnetic field penetrating the electron beam when driven. In this arrangement, the irradiation area in which the surface of the anode 42 is irradiated with the electron beam is a first irradiation area EB1, in which the first metal M1 is located when generating the first X-ray beam X1, and a second irradiation area EB2, in which the second metal M2 is located when generating the second X-ray beam X2. The first irradiation area EB1 and the second irradiation area EB2 are essentially identical in position relative to an external reference (for example, the ground).

[0027] Furthermore, it is desirable that the first direction (direction of the magnetic field penetrating the electron beam) intersects the propagation orientation of the electron beam at an angle of 85° or more and 90° or less (here, the orientation is given without specifying a direction. An angle between the first direction and a propagation direction of the electron beam should be 85° or more and 95° or less), and it is even more desirable that the first direction be substantially orthogonal to the propagation direction of the electron beam. It is also desirable that the sealed X-ray tube 31 be arranged with respect to the permanent magnet 32 ​​such that one direction of extension of the flat shape of the cross-section of the electron beam lies along the first direction (direction of the magnetic field penetrating the electron beam).With this arrangement, the electron beam can be deflected along the transverse direction of the flat shape of the electron beam's cross-section. Consequently, the first irradiation area EB1 and the second irradiation area EB2 can each be easily moved into the area where the first metal M1 is located, and into the area where the second metal M2 is located, respectively. In this embodiment, the propagation direction of the electron beam is a positive direction along the z-axis, and the direction (first direction) of the magnetic field penetrating the electron beam is a positive direction along the x-axis. Furthermore, the extension direction of the flat shape of the electron beam's cross-section is the direction along the x-axis, and the direction in which the electron beam is deflected by the magnetic field is a positive direction along the y-axis.

[0028] In the X-ray source section 11 of this embodiment, the irradiation area where the electron beam is directed can be adjusted to the first irradiation area EB1, where the first metal M1 is located, in the case of generating the first X-ray X1, and to the second irradiation area EB2, where the second metal M2 is located, in the case of generating the second X-ray X2, by means of only the rotary drive system 33, which rotates the sealed X-ray tube 31. The first irradiation area EB1 and the second irradiation area EB2 can be adjusted so that they are substantially the same in position with respect to the external reference (e.g., a floor), and the X-ray source can be set to the same position (focus position) as seen by the optical system 12.In other words, the X-ray source section 11 can select any one of the first X-ray beam X1 and the second X-ray beam X2 and emit the selected X-ray radiation to the optical system 12 under a common condition (with the same position of the X-ray source) only by controlling the rotary drive system 33.

[0029] It is desirable that the sealed X-ray tube 31 in this embodiment includes a first X-ray window 43A and a second X-ray window 43B, wherein the first X-ray window 43A is configured such that the X-ray beam X1 generated from the first irradiation area EB1, in which the first metal M1 arranged in the first area is irradiated with the electron beam, can pass through, and wherein the second X-ray window 43B is configured such that the X-ray beam X2 generated from the second irradiation area EB2, in which the second metal M2 arranged in the second area is irradiated with the electron beam, can pass through. In contrast to the one described in Fig. In the X-ray window 43 illustrated in Figure 2B, which is arranged so that the X-rays generated by the irradiation area EB are transmitted, the first irradiation area EB1 is moved from the center O when activated in the positive y-axis direction (see Figure 2B). Fig. 3C), and the first X-ray window 43A is located in the plane (xz-plane) that is orthogonal to the plane that is orthogonal to the surface (xy-plane) of the anode 42, and which includes the extension direction (x-axis) of a flat shape of the first irradiation area EB1 on the extension in the direction that intersects the surface of the anode 42 (or the extension direction of the flat shape of the first irradiation area EB1) at a predetermined angle, and is arranged in the side face of the sealed X-ray tube 31 (side face of the vacuum tube 40). Likewise, the second irradiation area EB2 is moved from the center O when driven in the positive y-axis direction (see Fig. 3D), and the second X-ray window 43B is located in the plane (xz-plane) that is orthogonal to the plane that is orthogonal to the surface (xy-plane) of the anode 42, and which includes an extension direction (x-axis) of a flat shape of the second irradiation area EB2 on the extension in the direction that intersects the surface of the anode 42 (or the extension direction of the flat shape of the second irradiation area EB2) at the predetermined angle, and is arranged in the side face of the sealed X-ray tube 31. Therefore, the first X-ray window 43A and the second X-ray window 43B are arranged such that they are rotationally symmetric (by 180°) with respect to the central axis of the cathode 41 and the anode 42 (and point-symmetric in the xy-plane).With the sealed X-ray tube 31 in this embodiment, which has the first X-ray window 43A and the second X-ray window 43B, the selected X-ray beam can be emitted to the optical system 12 under the identical geometric condition (with the same position of the X-ray source).

[0030] Therefore, according to this embodiment, the X-ray generating device can produce X-rays with different wavelengths without replacing the X-ray tube (sealed X-ray tube). To select one of the X-rays with a different wavelength, the sealed X-ray tube only needs to be rotated 180° by the rotary drive system. Furthermore, when the magnetic field generation section is fixed relative to the sealed X-ray tube, the magnitude of the magnetic field penetrating the electron beam remains constant, the deflection of the electron beam remains constant, and the irradiation area in which the surface of the anode is irradiated with the electron beam remains independent of the rotation of the sealed X-ray tube and thus remains in a constant position.With the sealed X-ray tube, including the first X-ray window and the second X-ray window, the X-ray beam can be extracted to the outside under identical radiation conditions, regardless of which of the X-ray beams with different wavelengths is selected. [Alternative embodiment 1]

[0031] An X-ray generating device according to an alternative embodiment 1 of the present invention is now described. In the X-ray generating device according to the embodiment of the present invention, the permanent magnet 32 ​​is fixed independently of the sealed X-ray tube 31, while the rotary drive system 33 rotates the sealed X-ray tube 31. In contrast, the X-ray generating device according to alternative embodiment 1 differs in that, while the rotary drive system 33 rotates the permanent magnet 32, the sealed X-ray tube 31 is fixed independently of the permanent magnet 32.In addition, the X-ray generation device according to alternative embodiment 1 differs from the embodiment of the present invention in that the X-ray window 43, through which both the X-ray beam X1, generated by the first irradiation area EB1, and the X-ray beam X2, generated by the second irradiation area EB2, can pass, is arranged in the side surface of the sealed X-ray tube 31. However, the X-ray generation device according to alternative embodiment 1 is otherwise identical to the generator according to the embodiment of the present invention.

[0032] Fig. 4A and Fig. Figure 4B shows schematic views illustrating one configuration of the X-ray source section 11 in alternative embodiment 1. Fig. 4A and Fig. 4B each correspond to Fig. 3C and Fig. 3D, whereby Fig. 4A is a top view of the anode 42 in the case of the generation of the first X-ray beam X1 and Fig. Figure 4B shows a top view of the anode 42 in the case of generating the second X-ray beam X2. In the case of generating the first X-ray beam X1, the rotary drive system 33 engages the permanent magnet 32, as shown in Figure 4B. Fig. As illustrated in Figure 4A, the permanent magnet 32 ​​is arranged on a negative x-axis side of the anode 42 to apply a magnetic field that penetrates the electron beam in the positive x-axis direction. Therefore, a Lorentz force is applied in the positive y-axis direction to deflect the electron beam in the positive y-axis direction and move the first irradiation area EB1 away from the center O in the positive y-axis direction. In the case of generating the second X-ray beam X2, the rotary drive system 33 rotates the permanent magnet 32, as shown in Figure 4A. Fig. As illustrated in Figure 4B, the permanent magnet 32 ​​is positioned on the positive x-axis side of the anode 42 to apply a magnetic field that penetrates the electron beam in a negative x-axis direction. Therefore, a Lorentz force is applied in a negative y-axis direction to deflect the electron beam in the negative y-axis direction and move the second irradiation area EB2 away from the center O in the negative y-axis direction.

[0033] The sealed X-ray tube 31 in alternative embodiment 1 includes the X-ray window 43, through which both the X-ray beam X1, generated by the first irradiation area EB1, and the X-ray beam X2, generated by the second irradiation area EB2, can pass, and which is arranged in the side surface of the sealed X-ray tube 31. The X-ray window 43 allows the light paths of the following two X-ray beams to pass through it. The first is a light path which, in the plane (xz-plane) that is orthogonal to the plane orthogonal to the surface (xy-plane) of the anode 42 and which contains the extension direction (x-axis) of the flat shape of the first irradiation area EB1, is a line of extension in a direction that intersects the surface of the anode 42 (or the extension direction of the flat shape of the first irradiation area EB1) at a predetermined angle.The second is a light path which, in the plane (xz-plane) orthogonal to the plane orthogonal to the surface (xy-plane) of the anode 42 and containing the extension direction (x-axis) of the flat shape of the second irradiation area EB2, is a line of extension in a direction that intersects the surface of the anode 42 (or the extension direction of the flat shape of the second irradiation area EB2) at a predetermined angle. With the sealed X-ray tube 31 in alternative embodiment 1, which contains the X-ray window 43, any X-ray beam with the selected wavelength can be emitted to the optical system 12 with a simple configuration. In contrast to the embodiment of the present invention, the position of the X-ray source along the y-axis direction is shifted between the case of the generation of the first X-ray beam X1 and the case of the generation of the second X-ray beam X2.However, the displacement along the y-axis direction between the first irradiation area EB1 and the second irradiation area EB2 is at a level in the range of 1 mm to 2 mm, and the X-ray generation device according to alternative embodiment 1 is optimal for measurements where the displacement is not a problem. [Alternative embodiment 2]

[0034] An X-ray generating device according to an alternative embodiment 2 of the present invention is described. In the X-ray generating device according to alternative embodiment 1, the rotary drive system 33 rotates the permanent magnet 32 ​​to reverse the orientation of a magnetic field penetrating the electron beam. In contrast, the X-ray generating device according to alternative embodiment 2 differs in that the rotary drive system 33 is not included and that a first permanent magnet 32A and a second permanent magnet 32B are instead arranged such that they are rotationally symmetric (by 180°) with respect to the central axis of the cathode 41 and the anode 42 (and point-symmetric with respect to the center O in the xy-plane).In addition, the X-ray generating device according to alternative embodiment 2 differs from alternative embodiment 1 in that a first antimagnetic shutter 35A is arranged between the first permanent magnet 32A and the sealed X-ray tube 31, and that a second antimagnetic shutter 35B is arranged between the second permanent magnet 32B and the sealed X-ray tube 31, but is otherwise identical to the X-ray generating device according to alternative embodiment 1. When the shutter is open, the first antimagnetic shutter 35A / second antimagnetic shutter 35B allows a magnetic field generated by the first permanent magnet 32A / second permanent magnet 32B to pass through, so that the first permanent magnet 32A / second permanent magnet 32B can apply the magnetic field penetrating the electron beam.In contrast, when the shutter is closed, the first antimagnetic shutter 35A / second antimagnetic shutter 35B blocks the magnetic field generated by the first permanent magnet 32A / second permanent magnet 32B, so that the first permanent magnet 32A / second permanent magnet 32B cannot apply the magnetic field penetrating the electron beam.

[0035] Fig. 5A and Fig. Figure 5B shows schematic views illustrating one configuration of the X-ray source section 11 in alternative embodiment 2. Fig. 5A and Fig. 5B each correspond to Fig. 4A and Fig. 4B, wherein Fig. 5A is a top view of the anode 42 in the case of the generation of the first X-ray beam X1 and Fig. Figure 5B shows a top view of the anode 42 in the case of the generation of the second X-ray beam X2. In the X-ray source section 11 of alternative embodiment 2, the first antimagnetic shutter 35A and the first permanent magnet 32A are arranged in the specified order on the negative side of the x-axis direction of the anode 42, and the second antimagnetic shutter 35B and the second permanent magnet 32B are arranged in the specified order on the positive side of the x-axis direction of the anode 42. The X-ray source section 11 in alternative embodiment 2 does not include the rotary drive system 33.

[0036] As in Fig. As shown in Figure 5A, to generate the first X-ray beam X1, the first antimagnetic shutter 35A is opened and the second antimagnetic shutter 35B is closed, so that the first permanent magnet 32A applies a magnetic field that penetrates the electron beam in the positive x-axis direction. Therefore, as in alternative embodiment 1, the first irradiation area EB1 is moved in the positive y-axis direction from the center O. As in Fig. As illustrated in Figure 5B, to generate the second X-ray beam X2, the second antimagnetic shutter 35B is opened and the first antimagnetic shutter 35A is closed, so that the second permanent magnet 32B applies a magnetic field that penetrates the electron beam in the negative x-axis direction. Therefore, as in alternative embodiment 1, the second irradiation area EB2 is moved in the negative y-axis direction from the center O. The sealed X-ray tube 31 in alternative embodiment 2 contains the same X-ray window 43 as in alternative embodiment 1. With this configuration, any X-ray beam with the selected wavelength can be emitted to the optical system 12 with a simple design. [Alternative embodiment 3]

[0037] An X-ray generating device according to an alternative embodiment 3 of the present invention is now described. In the X-ray generating device according to alternative embodiment 2, the first antimagnetic shutter 35A / second antimagnetic shutter 35B and the first permanent magnet 32A / second permanent magnet 32B are arranged on both sides of the anode 42. In contrast, the X-ray generating device according to alternative embodiment 3 differs in that an antimagnetic shutter 35 and the permanent magnet 32 ​​are arranged only on one side of the anode 42. Furthermore, the position of the second irradiation area EB2 differs from that of the embodiment of the present invention and alternative embodiments 1 and 2. Therefore, the first area and the second area are located differently on the surface of the anode 42.Furthermore, the arrangement of the X-ray window 43 differs from alternative embodiments 1 and 2. The X-ray generation device according to alternative embodiment 3 otherwise has the same structure as alternative embodiment 2.

[0038] Fig. 6A and Fig. Figure 6B shows schematic views illustrating one configuration of the X-ray source section 11 in alternative embodiment 3. Fig. 6A and Fig. 6B corresponds Fig. 4A and Fig. 4B, wherein the anode 42 is shown in alternative embodiment 1, and Fig. 5A and Fig. 5B, wherein the anode 42 is shown in alternative embodiment 2, wherein Fig. 6A a top view of the anode 42 in the case of the generation of the first X-ray beam X1, and Fig. Figure 6B shows a top view of the anode 42 in the case of the generation of the second X-ray beam X2. In the X-ray source section 11 of alternative embodiment 3, the antimagnetic shutter 35 and the permanent magnet 32 ​​are arranged in the specified order on the negative side of the x-axis direction of the anode 42. The X-ray source section 11 in alternative embodiment 3 does not include the rotary drive system 33.

[0039] As in Fig. As illustrated in Figure 6A, to generate the first X-ray beam X1, the antimagnetic shutter 35 is opened so that the permanent magnet 32 ​​applies a magnetic field that penetrates the electron beam in the positive direction of the x-axis. Therefore, as in alternative embodiments 1 and 2, the first irradiation area EB1 is moved in the positive y-axis direction from the center O. As in Fig. As illustrated in Figure 6B, to generate the second X-ray beam X2, the antimagnetic shutter 35 is closed, so that the permanent magnet 32 ​​does not apply a magnetic field to the electron beam. Therefore, in contrast to alternative embodiments 1 and 2, the second irradiation area EB2 is not deflected with respect to the center O, and the flat shape of the second irradiation area EB2 penetrates the center O. The second irradiation area EB2 coincides with the irradiation area EB, which is shown in Figure 6B. Fig. 2C is illustrated. In other words, the X-ray source section 11 in alternative embodiment 3 differs from alternative embodiments 1 and 2 in that the straight division line DL is moved in the positive y-axis direction from the center O and in the first region where the first metal M1 is located and the second region where the second metal M2 is located.

[0040] The sealed X-ray tube 31 in alternative embodiment 3 includes the X-ray window 43, through which both the X-ray beam X1, generated by the first irradiation area EB1, and the X-ray beam X2, generated by the second irradiation area EB2, can pass, and which is arranged in the side surface of the sealed X-ray tube 31. The X-ray window 43 allows the light paths of the following two X-ray beams to pass through it. As in alternative embodiments 1 and 2, the first light path is a line of extension in the plane (xz-plane) that is orthogonal to the plane orthogonal to the surface (xy-plane) of the anode 42 and that contains the extension direction (x-axis) of the flat shape of the first irradiation area EB1, in a direction that intersects the surface of the anode 42 (or the extension direction of the flat shape of the first irradiation area EB1) at a predetermined angle.The second is a light path that, in the plane (xz-plane) orthogonal to the plane orthogonal to the surface (xy-plane) of anode 42 and containing the extension direction (x-axis) of the flat shape of the second irradiation area EB2, is a line of extension in a direction that intersects the surface of anode 42 (or the extension direction of the flat shape of the second irradiation area EB2) at a predetermined angle. In this example, the second irradiation area EB2 penetrates the center O.

[0041] With the sealed X-ray tube 31 in alternative embodiment 3, which includes the X-ray window 43, any X-ray beam with the selected wavelength can be emitted to the optical system 12 with a simple design. As in alternative embodiments 1 and 2, the position of the X-ray source is shifted along the y-axis between the case of the generation of the first X-ray beam X1 and the case of the generation of the second X-ray beam X2. However, the shift along the y-axis between the first irradiation area EB1 and the second irradiation area EB2 is within a range of 0.5 mm to 1 mm, and the X-ray generation device according to alternative embodiment 3 is optimal for measurements where the shift is not a problem.The straight dividing line DL of the anode 42 in alternative embodiment 3 does not penetrate the center O and is moved in the positive direction of the y-axis. The first region, in which the first metal M1 is arranged, is narrower compared to those in alternative embodiments 1 and 2, and the second region, in which the second metal M2 is arranged, is wider compared to those in alternative embodiments 1 and 2.

[0042] In the X-ray generating device according to alternative embodiment 3, the center of the cathode 41 is arranged above the center O of the anode 42, but the present invention is not limited thereto. For example, the cathode 41 can be arranged such that it is moved in the negative y-axis direction from the center O of the anode 42, as seen from above, so that a center line between the first irradiation area EB1 and the second irradiation area EB2 penetrates the center O. In this case, it is desirable that the straight dividing line DL penetrates the center O as in alternative embodiments 1 and 2.

[0043] The X-ray generation device and the X-ray analysis device according to the embodiment of the present invention have been described together with alternative embodiments 1 to 3. The present invention and alternative embodiments 1 to 3 are widely applicable, without being limited to the embodiment mentioned above. For example, the magnetic field generation section in the embodiment mentioned above is, for example, the permanent magnet 32. However, the magnetic field generation section is not limited to this and can be an electromagnetic coil. Furthermore, the straight dividing line DL of the anode 42 is the center line between the first irradiation area EB1 and the second irradiation area EB2, but the present invention is not limited to this.It is only required that the first area includes the first irradiation area EB1, that the first metal M1 is located in at least the first irradiation area EB1, that the second area includes the second irradiation area EB2, and that the second metal M2 is located in at least the second irradiation area EB2.

[0044] Furthermore, in the embodiment mentioned above, for example, the X-ray window is arranged such that the X-ray beam is extracted in the oblique direction in the plane containing the extension direction of the irradiation area with the flat shape and which is perpendicular to the surface of the anode. Therefore, the X-ray generating device effectively serves as a point-shaped X-ray source. However, the present invention is not limited to this. For example, the X-ray generating device can serve as a linear X-ray source by arranging an X-ray window with a length corresponding to a length in the extension direction of the irradiation area in the direction perpendicular to the extension direction of the flat shape of the irradiation area and forming a predetermined angle with the surface of the anode.

Claims

[1] X-ray generating device (11), comprising: a sealed X-ray tube (31) with a cathode (41) from which thermionic electrons are emitted and an anode (42) which is irradiated with an electron beam obtained by accelerating the thermionic electrons with a potential difference applied between the cathode (41) and the anode (42); a magnetic field generating section (32) arranged near the sealed X-ray tube (31) to apply a magnetic field to the electron beam, the magnetic field extending in a first direction that intersects a propagation direction of the electron beam; and a rotary drive system (33) designed to rotate the sealed X-ray tube (31) with respect to a central axis of the cathode (41) and the anode (42), wherein the anode (42) has a surface with a first region and a second region, which are arranged on one side and another side respectively with respect to a straight dividing line passing through an intersection of the surface and the central axis; wherein the first region comprises a first metal arranged therein and the second region comprises a second metal arranged therein, wherein the second metal differs from the first metal, wherein the sealed X-ray tube (31) is driven by the rotary drive system (33) to a position in which the sealed X-ray tube (31) is arranged with respect to the magnetic field generating section (32) such that the straight dividing line which separates the first anode region from the second anode region lies along the first direction of the magnetic field. [2] X-ray generating device (11) according to claim 1, wherein the electron beam has a cross-section with an extending flat shape, and wherein, when the sealed X-ray tube (31) is driven, the sealed X-ray tube (31) is arranged in relation to the magnetic field generating section (32) such that one extension direction of the extending flat shape lies along the first direction. [3] X-ray generating device (11) according to claim 1 or 2, wherein the magnetic field generating section (32) is a permanent magnet. [4] X-ray generating device (11) according to one of claims 1 to 3, wherein the surface of the anode (42) has a circular shape and the intersection of the surface and the central axis substantially coincides with a center of the circular shape. [5] X-ray generating device (11) according to one of claims 1 to 4, wherein the first direction is substantially orthogonal to the propagation direction of the electron beam. [6] X-ray generating device (11) according to any one of claims 1 to 5, wherein the sealed X-ray tube (31) includes a first X-ray window (43A) and a second X-ray window (43B), wherein the first X-ray window (43A) is configured to allow an X-ray beam generated from a first irradiation area in which the first metal arranged in the first area is irradiated with the electron beam to pass through, wherein the second X-ray window (43B) is configured to allow an X-ray beam generated from a second irradiation area in which the second metal arranged in the second area is irradiated with the electron beam to pass through. [7] X-ray generating device (11) according to any one of claims 1 to 6, wherein the filament of the cathode (41) is provided on the central axis and wherein the longitudinal direction of the cathode (41) is along the straight dividing line. [8] X-ray analysis apparatus (1), comprising: the X-ray generating device (11) according to any one of claims 1 to 7; a support base (14) designed to support a sample (100) which is to be irradiated with an X-ray beam emitted by the X-ray generating device (11); and a detector (15) designed to detect scattered X-rays generated by the sample (100).

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