JP2007207539A - X-ray source and fluorescent x-ray analysis system - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide X-ray source 11 capable of effectively generating a characteristic X-ray 21. <P>SOLUTION: A second target 19 is superposed on a first target 18. An electron beam 15 generated by an electron gun 14 enters the first target 18, and the first target 18 allows a continuous X-ray 20 to pass therethrough to emit it. The second target 19 allows the characteristic X-ray 21, which is excited by the continuous X-ray 20 emitted from the first target 18, to pass therethrough to emit it. By superposing the second target 19 on the first target 18, the continuous X-ray 20 emitted from the first target 18 effectively performs excitation at the second target 19 to effectively generate the characteristic X-ray 21. <P>COPYRIGHT: (C)2007,JPO&INPIT

Description

  The present invention relates to an X-ray source that emits characteristic X-rays and a fluorescent X-ray analyzer using the X-ray source.

  In a general X-ray source, braking X-rays and characteristic X-rays peculiar to a target are emitted by making electrons accelerated by a high voltage incident on a target that is an anode (see, for example, Patent Document 1).

  The braking X-ray is a continuous energy spectrum, and the energy spectrum changes depending on the incident electron energy, whereas the characteristic X-ray does not depend on the electron energy and is monochromatic energy. Therefore, in the X-ray fluorescence analyzer, by exciting the sample using characteristic X-rays of known energy, it becomes easy to separate the fluorescent X-ray signal and the noise component that is the scattering of the incident X-ray, Elemental analysis at a high S / N ratio is possible.

  FIG. 19 shows an example of a general configuration of a high-resolution X-ray fluorescence analyzer utilizing the above-described characteristic X-rays. Here, using a general X-ray source 1, continuous X-rays 2 that are primary X-rays of a continuous energy spectrum emitted from the X-ray source 1 are incident on the secondary target 3, and characteristic X-rays 4 Is emitted to the sample 6 through the collimator 5 installed outside, and the X-ray detector 8 detects the fluorescent X-rays 7 emitted by exciting the elements on the surface of the sample 6.

In the emission method of the characteristic X-ray 4 in this configuration, the X-ray source 1 and the secondary target 3 must be installed apart from each other. Since the continuous X-ray 2 is emitted in the 4π direction, which is the entire circumferential direction, and its intensity decreases in inverse proportion to the square of the distance, in the conventional configuration, the secondary X-ray 2 emitted from the X-ray source 1 is secondary. In order to increase the intensity of the characteristic X-ray 4 emitted from the secondary target 3 because the efficiency of irradiating the target 3 is low, it is necessary to provide a high-power X-ray source 1, thereby high-resolution X-ray fluorescence analysis This increases the size of the apparatus, increases the power consumption, increases the scale of X-ray shielding, and consequently increases the cost, which is a factor that strengthens restrictions on diffusion (see, for example, Non-Patent Document 1).
JP 2004-28845 A (page 4-5, FIG. 1-2) Current Status and Prospect of X-ray Fluorescence Analysis Izumi Nakai Applied Physics Vol. 74 No. 4 (2005) pp. 455-456

  In the high-resolution X-ray fluorescence analyzer described above, the most important issue is to provide an X-ray source 1 that can efficiently generate characteristic X-rays 4. The configuration using the secondary target 3 is an effective method for suppressing the mixing ratio of unnecessary components (noise) and maintaining the high monochromaticity and emitting the characteristic X-ray 4. Since the target 3 is placed outside the X-ray source 1 and the continuous X-ray 2 is emitted in all directions (4π direction), it is attenuated by the square of the distance and excites the secondary target 3. The utilization factor of the continuous X-ray 2 is reduced. Furthermore, since a space for arranging the secondary target 3 and the monochromatic filter is necessary outside the X-ray source 1, there is a problem that the system is enlarged.

  In addition, as a secondary effect, it is necessary to set a long distance from the secondary target 3 to the sample 6, and therefore, in order to ensure the strength of the characteristic X-ray 4 to the sample 6, a large strength is required. The X-ray source 1 is required to be applied, which causes an increase in the X-ray shielding scale and an increase in the apparatus price.

  The present invention has been made in view of these points, and an object of the present invention is to provide an X-ray source that can efficiently generate characteristic X-rays, and a fluorescent X-ray analyzer using the X-ray source.

  The X-ray source of the present invention is arranged to overlap the primary target, an electron gun that generates an electron beam, a primary target that receives an electron beam from the electron gun and transmits X-rays, and emits the X-ray. A secondary target that transmits and emits characteristic X-rays excited by X-rays emitted from the primary target.

  The X-ray source according to the present invention includes a vacuum container having an X-ray transmission window, an electron gun that generates an electron beam in the vacuum container, and an electron beam incident from the electron gun. Then, the primary target that emits X-rays in the reflection direction and the periphery around the primary target in the vacuum vessel are arranged opposite to each other and excited by the X-rays emitted from the primary target And a secondary target that emits characteristic X-rays in a reflection direction toward the X-ray transmission window.

  The X-ray source of the present invention includes a vacuum container having an X-ray transmission window, an electron gun that generates a ring-shaped electron beam in the vacuum container, and a ring-shaped arrangement in the vacuum container. A primary target in which a ring-shaped electron beam is incident from a gun and emits X-rays in a reflection direction is disposed opposite to the center of the primary target in the vacuum vessel, and is emitted from the primary target. And a secondary target that emits characteristic X-rays excited by X-rays in a reflection direction toward the X-ray transmission window.

  An X-ray source according to the present invention includes a vacuum container having an X-ray transmission window, an electron gun having a ground potential that generates an electron beam disposed in the vacuum container, the electron gun disposed in the vacuum container, A primary target that emits an X-ray in the reflection direction when an electron beam is incident from a gun, and an X-ray that is disposed at the position of the X-ray transmission window in the vacuum vessel and excited by the X-ray emitted from the primary target And a secondary target that transmits and emits characteristic X-rays.

  The X-ray source of the present invention includes an electron gun that generates an electron beam, a primary target that receives an electron beam from the electron gun, transmits X-rays, and emits, and overlaps the primary target. A plurality of secondary targets that are movable with respect to the X-ray generation position of the secondary target, and the secondary target arranged at the X-ray generation position is excited by the X-rays emitted from the primary target. And a secondary target body that transmits and emits characteristic X-rays.

  The X-ray source of the present invention includes a vacuum container having an X-ray transmission window, an electron gun that generates an electron beam in the vacuum container, and different primary targets and secondary targets that are disposed in the vacuum container. And a plurality of sets of target portions that can be moved with respect to an electron beam incident position where an electron beam is incident from the electron gun, and are arranged at the electron beam incident position. The primary target of the target unit transmits and emits X-rays by the incidence of an electron beam, and the secondary target transmits characteristic X-rays excited by X-rays emitted from the primary target and transmits the X-rays. A target body discharged from the window and a moving mechanism for moving the target body in the vacuum vessel are provided.

  The X-ray source of the present invention includes a vacuum container having an X-ray transmission window, an electron gun that generates an electron beam in the vacuum container, and different primary targets and secondary targets that are disposed in the vacuum container. And a plurality of sets of target parts that are combined with each other, and the plurality of sets of target parts are movable with respect to an electron beam incident position where an electron beam is incident from the electron gun. The primary target of the arranged target portion transmits and emits X-rays by the incidence of an electron beam, and the secondary target transmits and emits characteristic X-rays excited by X-rays emitted from the primary target. Among the Kβ rays and Kα rays included in the characteristic X-rays emitted from the secondary target, the filter attenuates the Kβ rays and transmits the Kα rays to release them from the X-ray transmission window. A target body, those that comprise a moving mechanism for moving the target object in the vacuum chamber.

  The X-ray source according to the present invention includes a vacuum container having an X-ray transmission window movably provided, an electron gun for generating an electron beam in the vacuum container, and an X-ray transmission window in the vacuum container. Electrons that are provided and have a plurality of sets of target portions in which different primary targets and secondary targets are combined in an overlapping manner, and the plurality of sets of target portions enter an electron beam from the electron gun by the movement of the X-ray transmission window The primary target of the target unit disposed at the electron beam incident position is movable with respect to the beam incident position, and transmits and emits X-rays by the incidence of the electron beam, and the secondary target is emitted from the primary target. And a target body that transmits characteristic X-rays excited by the X-rays and emits them from the X-ray transmission window.

  The X-ray source according to the present invention includes a vacuum container having an X-ray transmission window movably provided, an electron gun for generating an electron beam in the vacuum container, and an X-ray transmission window in the vacuum container. A plurality of sets of target units provided by combining different primary targets, secondary targets, and filters, and the plurality of sets of target units receive an electron beam from the electron gun as the X-ray transmission window moves. The primary target of the target unit arranged at the electron beam incident position is allowed to move with respect to the electron beam incident position, and transmits and emits X-rays by the incidence of the electron beam, and the secondary target is released from the primary target. The characteristic X-rays excited by the emitted X-rays are transmitted and emitted, and Kβ of Kβ rays and Kα rays included in the characteristic X-rays emitted from the secondary target are Kβ. It was attenuated, but that and a target body to be emitted from the X-ray transmission window by transmitting Kα line.

  The X-ray tendency analyzer of the present invention detects the X-ray source that irradiates a sample with characteristic X-rays, and fluorescent X-rays that are emitted by excitation of elements on the surface of the sample by irradiation with the characteristic X-rays. And an X-ray detector.

  According to the X-ray source of the present invention, by overlapping the primary target and the secondary target, the X-rays emitted from the primary target can be efficiently used for excitation of the secondary target, and the characteristic X-rays can be efficiently used. Can occur.

  In addition, according to the X-ray source of the present invention, the primary target and the secondary target are arranged in the vacuum vessel, so that the distance between the primary target and the secondary target can be shortened. The X-rays emitted from the target can be efficiently used for excitation of the secondary target, the characteristic X-rays can be generated efficiently, and the electron beam is emitted in the reflection direction by the primary target. Compared to the transmission method, it has superior thermal shock resistance, and can cope with an increase in the amount of electron beam current for increasing the output.

  In addition, according to the X-ray fluorescence analyzer of the present invention, the apparatus can be miniaturized by using the X-ray source.

  Hereinafter, embodiments of the present invention will be described with reference to the drawings.

  1 and 2 show a first embodiment of an X-ray source.

  In FIG. 1, an X-ray source 11 has a vacuum container 12 whose inside is kept in vacuum, and an X-ray transmission window 13 for emitting X-rays to the outside is disposed at one end of the vacuum container 12.

  An electron gun 14 is disposed at the other end of the vacuum container 12, and an electron beam is directed toward the X-ray transmission window 13 at the end of the electron gun 14 positioned in the vacuum container 12 and facing the X-ray transmission window 13. An emitter 16 that emits 15 is provided. The electron gun 14 generates and accelerates an electron beam 15 by a driving power source 17.

  In the X-ray transmission window 13, a primary target 18 facing the electron gun 14 in the vacuum vessel 12 and a secondary target 19 arranged in close contact with each other outside the primary target 18 are arranged. Yes.

  As shown in FIG. 2, the primary target 18 emits a continuous X-ray 20 as a primary X-ray that is an X-ray upon incidence of the electron beam 15, and transmits the continuous X-ray 20 to the secondary target 19. Let The secondary target 19 emits characteristic X-rays 21 excited by continuous X-rays 20 that are transmitted through and emitted from the primary target 18, and transmits the characteristic X-rays 21 to be emitted outside the vacuum vessel 12. . The characteristic X-ray 21 includes a Kα ray having a long wavelength and a Kβ ray having a short wavelength. The ratio of Kα rays and Kβ rays is about 10: 2.

  It is assumed that the electron beam 15 obtained by the drive power source 17 has sufficient energy to excite and emit the characteristic X-ray 21 of the secondary target 19, that is, the Kα ray and Kβ ray.

  Further, in order to effectively emit the characteristic X-rays 21 of the secondary target 19, it is an optimal combination to select an element that is about 2 larger in atomic number than the secondary target 19 for the primary target 18. For example, a combination is selected in which the primary target 18 is Cu (copper) with an atomic number 29 and the secondary target 19 is Co (cobalt) with an atomic number 27.

  The continuous X-rays 20 emitted from the primary target 18 pass through the primary target 18 and enter the secondary target 19 that is in close contact with the primary target 18. The divergence of continuous X-rays 20 can be minimized and can be efficiently used for excitation of the secondary target 19.

  As described above, the small X-ray source 11 capable of efficiently emitting the target energy characteristic X-ray 21 can be provided.

  In consideration of the thickness of the primary target 18, considering that the penetration depth of several μm into the primary target 18 is sufficient for the energy of the incident electrons, A surface of which the element of the primary target 18 is coated or plated may be used, which can be effective in suppressing attenuation of the continuous X-rays 20 transmitted through the primary target 18.

  The secondary target 19 has the function of the X-ray transmission window 13, but it is necessary to select a sufficient thickness that does not cause deformation or destruction due to a pressure difference. Therefore, when aiming at the emission of low energy characteristic X-rays 21, a material having a small X-ray attenuation rate such as Be (beryllium) is used as the X-ray transmission window 13, and 2 on the X-ray transmission window 13. It is also possible to apply a structure in which the secondary target 19 and the primary target 18 are coated to a required thickness.

  Further, as an example of selection of the two targets 18 and 19, the above-described atomic number matching condition is satisfied, and the secondary target 19 is electrically non-conductive, or Ge (germanium), Si (silicon) If the primary target 18 is a conductor, a stable operation is possible without causing charge accumulation (charge-up) due to the incidence of the electron beam 15.

  Next, FIGS. 3 and 4 show a second embodiment.

  In this embodiment, in the X-ray source 11 having the configuration of the first embodiment, the wavelength of the Kα ray and Kβ ray of the characteristic X ray 21 of the secondary target 19 is short outside the secondary target 19. This is a configuration in which a K edge filter 22 serving as a filter that attenuates Kβ rays and transmits Kα rays having a long wavelength is arranged in a close contact state.

  It is necessary to select an appropriate combination of the secondary target 19 and the K edge filter 22, and the element of the K edge filter 22 is about 1 smaller in atomic number than the secondary target 19 that emits the characteristic X-ray 21. Things are appropriate. For example, a combination is selected in which the secondary target 19 is Cu (copper) with an atomic number 29 and the K edge filter 22 is Ni (nickel) with an atomic number 28.

  The K edge filter 22 has a large attenuation effect on Kβ rays having a short wavelength among the Kα rays and Kβ rays of the characteristic X-ray 21 of the secondary target 19, and transmits Kα rays having a long wavelength. Due to the action, the ratio of Kα rays having a long wavelength is remarkably increased, and characteristic X-rays 21 having high monochromaticity can be emitted.

  As described above, it is possible to provide a small X-ray source 11 having a high Kα ray ratio and excellent monochromaticity among the characteristic X-rays 21 of the secondary target 19.

  Also in this embodiment, the thicknesses of the targets 18 and 19 and the K edge filter 22 need to be set in consideration of the target X-ray attenuation and monochromaticity. When a sufficient thickness cannot be obtained as 13, as in the first embodiment, a material having a small X-ray attenuation rate such as Be (beryllium) is used as the X-ray transmission window 13, and each target 18, 19, A configuration in which the K edge filter 22 is coated can be applied.

  Next, FIG. 5 shows a third embodiment.

  In this embodiment, in the configuration of the X-ray source 11 similar to that of the first embodiment, the primary target 18 on which the electron beam 15 is incident has a conical shape, and the top is on the axis of the electron beam 15. The secondary target 19 is formed in a cylindrical shape and is opposed to the periphery of the primary target 18 on a concentric circle centering on the axis of the electron beam 15, that is, the primary target 18. This is the configuration. The inner peripheral surface of the secondary target 19 is parallel to the surface of the conical primary target 18, for example, and the characteristic X-rays 21 excited by continuous X-rays 20 incident from the primary target are transmitted to the X-ray transmission window 13. It is comprised so that it may discharge | emit in the direction of the direction of reflection.

  Then, the electron beam 15 generated by the electron gun 14 passes through the central opening of the secondary target 19 and enters the surface of the conical primary target 18, and the secondary target 19 is irradiated from the surface of the primary target 18. Continuous X-rays 20 are emitted in the direction of reflection toward the inner peripheral surface. The characteristic X-ray 21 emitted from the primary target 18 is incident on the inner peripheral surface of the secondary target 19, and the characteristic X-ray 21 is reflected from the inner peripheral surface of the secondary target 19 toward the X-ray transmission window 13. Release in the direction. The characteristic X-ray 21 emitted from the secondary target 19 passes through the X-ray transmission window 13 and is emitted to the outside.

  In this case, the distance between the primary target 18 and the secondary target 19 is longer than that in the configuration of the first embodiment, and the irradiation and excitation efficiency to the secondary target 19 are reduced. Since the primary target 18 and the secondary target 19 are arranged on each other, the distance between the primary target 18 and the secondary target 19 can be shortened, and two continuous X-rays 20 emitted from the primary target 18 can be obtained. It can be used efficiently for the excitation of the next target 19, and the characteristic X-ray 21 can be generated efficiently. In addition, since both the primary target 18 and the secondary target 19 can be applied with a bulk structure having an arbitrary thickness and a large heat capacity, the thermal shock is superior to the transmission method as in the first embodiment. As a result, the incident electron beam current amount can be set large, and the high-power characteristic X-ray 21 can be emitted.

  Further, when the amount of incident electron beam current is further increased, the primary target 18 and, if necessary, the secondary target 19 can also be cooled with water to further improve the heat resistance. .

  As described above, it is possible to provide the small X-ray source 11 that ensures the durability of the targets 18 and 19 even under a large current condition and enables the emission of the high-power characteristic X-ray 21.

  Next, FIG. 6 shows a fourth embodiment.

  In this embodiment, in the X-ray source 11 having the configuration of the third embodiment, a K edge filter 22 is provided outside the X-ray transmission window 13.

  The K edge filter 22 has a large attenuation effect on Kβ rays having a short wavelength among the Kα rays and Kβ rays of the characteristic X-ray 21 of the secondary target 19, and transmits Kα rays having a long wavelength. Due to the action, the ratio of Kα rays having a long wavelength is remarkably increased, and characteristic X-rays 21 having high monochromaticity can be emitted.

  As described above, the small X-ray source 11 can ensure the durability of the targets 18 and 19 even under a large current condition, and can emit the high-power characteristic X-ray 21 with higher monochromaticity. Can provide.

  Next, FIG. 7 shows a fifth embodiment.

  In this embodiment, in the configuration of the X-ray source 11 similar to that of the third embodiment, the emitter 16 of the electron gun 14 has a ring shape for generating a ring-shaped electron beam 15, and the primary The target 18 is formed in a ring shape coaxial with the axis of the ring-shaped electron beam 15 so that the ring-shaped electron beam 15 generated from the emitter 16 of the electron gun 14 is incident, and the secondary target 19 is a primary target. In this configuration, it is arranged at the center of 18 so as to face the inner peripheral surface of the primary target 18. The inner peripheral surface of the primary target 18 is an inclined surface that expands and inclines toward the electron gun, and emits continuous X-rays 20 in the reflection direction toward the central secondary target 19. The secondary target 19 has a conical shape and is arranged with the top facing the X-ray transmission window 13. For example, the surface of the secondary target 19 is parallel to the inner peripheral surface of the primary target 18 and is incident from the primary target 18. The characteristic X-rays 21 excited by the continuous X-rays 20 are emitted in the reflection direction toward the X-ray transmission window 13.

  The ring-shaped electron beam 15 generated by the electron gun 14 passes around the primary target 18 and is incident on the inner peripheral surface of the primary target 18, and from the surface of the primary target 18 to the secondary target 19. Continuous X-rays 20 are emitted in the direction of reflection toward the surface. The continuous X-rays 20 emitted from the primary target 18 are incident on the surface of the secondary target 19 and emit characteristic X-rays 21 from the surface of the secondary target 19 in the reflection direction toward the X-ray transmission window 13. . The characteristic X-ray 21 emitted from the secondary target 19 passes through the X-ray transmission window 13 and is emitted to the outside.

  Also in this case, the distance between the primary target 18 and the secondary target 19 is longer than that in the configuration of the first embodiment, and the irradiation and excitation efficiency to the secondary target 19 are reduced. By disposing the primary target 18 and the secondary target 19 in 12, it is possible to shorten the distance between the primary target 18 and the secondary target 19, and continuous X-rays 20 emitted from the primary target 18. Can be efficiently used for excitation of the secondary target 19, and characteristic X-rays 21 can be generated efficiently.

  As in the third embodiment, the primary target 18 can have a large heat capacity, and can be easily cooled through the vacuum vessel 12 and the X-ray transmission window 13. It becomes possible to increase the current and energy of electrons, and there is an advantage that the number of generated continuous X-rays 20 and the characteristic X-rays 21 associated therewith are increased. Further, the generation point of the characteristic X-ray 21 can be formed into a spot shape, and further, the primary target 18 serves as a collimator for suppressing the spread of the characteristic X-ray 21 so that the characteristic X-ray 21 has a beam shape with a small divergence angle. This makes it possible to remove the background by X-ray irradiation to areas other than the examination site.

  In this way, a small X-ray source 11 capable of extracting a large dose of characteristic X-ray 21 in the form of a beam can be provided.

  Next, FIG. 8 shows a sixth embodiment.

  In this embodiment, in the X-ray source 11 of the fifth embodiment, a K edge filter 22 is installed outside the X-ray transmission window 13.

  The K edge filter 22 has a large attenuation effect on Kβ rays having a short wavelength among the Kα rays and Kβ rays of the characteristic X-ray 21 of the secondary target 19, and transmits Kα rays having a long wavelength. Due to the action, the ratio of Kα rays having a long wavelength is remarkably increased, and characteristic X-rays 21 having high monochromaticity can be emitted.

  In this way, it is possible to provide a small X-ray source 11 capable of enhancing the monochromaticity and extracting the large dose of characteristic X-rays 21 in the form of a beam.

  Next, FIG. 9 shows a seventh embodiment.

  In this embodiment, contrary to the configuration of each of the above embodiments, the electron gun 14 is set to the ground potential and the primary target 18 is set to the high voltage potential.

  The electron gun 14 preferably has a ring structure, and the primary target 18 has a frustoconical shape, and the top portion is arranged at the center of the ring-shaped electron gun 14 toward the X-ray transmission window 13. The surface of the truncated cone-shaped primary target 18 is configured so that an electron beam 15 is incident from the electron gun 14 and the continuous X-rays 20 are emitted in a reflection direction toward the X-ray transmission window 13.

  A secondary target 19 is disposed in the X-ray transmission window 13, and a K edge filter 22 is disposed outside the secondary target 19.

  Then, the electron beam 15 generated by the ring-shaped electron gun 14 is incident on the surface of the frustoconical primary target 18 and is directed from the surface of the primary target 18 toward the secondary target 19 of the X-ray transmission window 13. Continuous X-rays 20 are emitted in the reflection direction. The continuous X-rays 20 emitted from the primary target 18 enter the secondary target 19, and the characteristic X-rays 21 are transmitted from the secondary target 19 and emitted. The characteristic X-ray 21 emitted from the secondary target 19 passes through the K edge filter 22 of the X-ray transmission window 13 and is emitted to the outside.

  Also in this case, the distance between the primary target 18 and the secondary target 19 is longer than that in the configuration of the first embodiment, and the irradiation and excitation efficiency to the secondary target 19 are reduced. By disposing the primary target 18 and the secondary target 19 in 12, it is possible to shorten the distance between the primary target 18 and the secondary target 19, and continuous X-rays 20 emitted from the primary target 18. Can be efficiently used for excitation of the secondary target 19, and characteristic X-rays 21 can be generated efficiently.

  Further, as in the third embodiment, the primary target 18 can be of a structure with a large heat capacity, which makes it possible to increase the current and energy of incident electrons, and to generate the continuous target. There is an advantage that the characteristic X-ray 21 is increased along with the increase of the X-ray 20.

  In this way, the small cathode-grounded X-ray source 11 capable of efficiently emitting the target energy characteristic X-ray 21 can be provided.

  A material having excellent X-ray transmission characteristics such as Be (beryllium) may be used as the X-ray transmission window 13 and a K edge filter 22 may be attached to the outside of the X-ray transmission window 13.

  Next, FIG. 10 shows an eighth embodiment.

  In this embodiment, in the configuration of the X-ray source 11 similar to that of the first embodiment, a secondary target body 31 is provided so as to be superimposed on the outside of the primary target 18. The secondary target body 31 has, for example, a plurality of secondary targets 19a, 19b, 19c, and 19d that can generate characteristic X-rays 21 of different energies. It is provided at equal intervals on the same circumference of the rotating body 33 that can rotate as a center.

  The rotating shaft 32 of the rotating body 33 can be rotated through a rotating mechanism (not shown) as a moving mechanism, and overlaps with the primary target 18 and the secondary targets 19a to 19d overlap the primary target 18 with respect to the X-ray generation position. Any one is selectively arranged.

  The secondary target is replaced by providing a plurality of secondary targets 19a to 19d and arranging any one of the plurality of secondary targets 19a to 19d with respect to the X-ray generation position of the primary target 18. Therefore, there is an advantage that characteristic X-rays 21 having different energies can be easily extracted without changing the X-ray generation point. When the X-ray source 11 is applied to a fluorescent X-ray analyzer, the analysis can be performed without breaking the measurement system such as the X-ray generation point and the sample position.

  In this way, it is possible to provide a small X-ray source 11 capable of selecting and emitting characteristic X-rays 21 having different energies without changing the X-ray generation point.

  Next, FIG. 11 shows a ninth embodiment.

  In this embodiment, the X-ray source 11 of the eighth embodiment includes a filter body 35 disposed outside the secondary target body 31. This filter body 35 has, for example, K edge filters 22a, 22b, 22c, and 22d as filters corresponding to the respective secondary targets 19a to 19d that generate characteristic X-rays 21 of different energies, and these K edge filters 22a to 22d. 22d is provided on the same circumference of the rotator 36 that is rotatable about the rotation shaft 32 and at positions corresponding to the secondary targets 19a to 19d. The rotating body 33 of the secondary target body 31 and the rotating body 36 of the filter body 35 may be an integrated disk or a separate disk.

  Then, by arranging any one of the plurality of secondary targets 19a to 19d with respect to the X-ray generation position of the primary target 18, any one of the corresponding K edge filters 22a to 22d is also provided. Be placed. Therefore, it is not necessary to move the X-ray source 11 for exchanging the secondary target or K-edge filter. Similar to the eighth embodiment, the characteristic X-rays of different energies can be obtained without changing the X-ray generation point. There is an advantage that 21 can be taken out easily.

  The K edge filters 22a to 22d have a large attenuation effect on the short wavelength Kβ line of the Kα line and Kβ line of the characteristic X-ray 21 of the secondary targets 19a to 19d. Since it acts to transmit light, the proportion of Kα rays having a long wavelength is remarkably increased, and characteristic X-rays 21 having high monochromaticity can be emitted.

  As described above, a small X-ray source 11 that can selectively emit characteristic X-rays 21 having different energies without changing the X-ray generation point and that can obtain characteristic X-rays 21 with high monochromaticity is provided. it can.

  Next, FIG. 12 shows a tenth embodiment.

  In this embodiment, a target body 41 that is rotatably arranged in the vacuum vessel 12 is provided in the configuration of the X-ray source 11 similar to that of the first embodiment. This target body 41 has a plurality of target portions 42a, 42b, 42c, and 42d in which different primary targets 18a, 18b, 18c, and 18d and appropriate secondary targets 19a, 19b, 19c, and 19d are combined in an overlapping manner. The primary targets 18a to 18d and the secondary targets 19a to 19d are provided at equal intervals on the same circumference of the rotating bodies 44 and 45 that rotate about the rotating shaft 43. The rotating body 44 and the rotating body 45 may be an integrated disk or separate disks.

  A rotation mechanism 46 is provided as a moving mechanism for rotating the target body 41 in the vacuum container 12 from the outside of the vacuum container 12.

  Then, the target body 41 rotates any one of the plurality of target portions 42a to 42d around the rotation axis 43 with respect to the electron beam incident position where the electron beam 15 is incident from the electron gun 14. By arranging, the primary targets 18a to 18d of the target portions 42a to 42d arranged at the electron beam incident positions transmit the continuous X-rays 20 by the incidence of the electron beam 15, and the secondary targets 19a to 19d are emitted. The characteristic X-rays 21 excited by the continuous X-rays 20 emitted from the primary targets 18 a to 18 d are transmitted and emitted from the X-ray transmission window 13.

  By selecting the target portions 42a to 42d, the characteristic X-ray 21 of the selected energy can be easily extracted, and at the time of the selection, it becomes unnecessary to replace the X-ray source 11, and the X-ray generation point can be fixed. There are advantages you can do.

  Further, since the function of the vacuum partition is provided by the independent X-ray transmission window 13, the thicknesses of the primary targets 18a to 18d and the secondary targets 19a to 19d can be arbitrarily selected.

  As described above, it is possible to provide a small X-ray source 11 capable of selecting and emitting several characteristic X-rays 21 without changing the X-ray generation point.

  Next, FIG. 13 shows an eleventh embodiment.

  In this embodiment, the X-ray source 11 of the tenth embodiment includes a filter body 48 disposed outside the secondary target body 31. The filter body 48 has K edge filters 22a, 22b, 22c, and 22d corresponding to the target portions 42a to 42d, and the K edge filters 22a to 22d can rotate around the rotation shaft 43. Are provided at positions corresponding to the respective secondary targets 19a to 19d. The rotating shaft 43 is provided through the X-ray transmission window 13.

  The secondary targets 19a to 19d overlapped with the primary targets 18a to 18d and the K edge filters 22a to 22d rotate integrally with each other, thereby improving the monochromaticity. There is an advantage that the characteristic X-ray 21 can be selected and emitted.

  As described above, it is possible to provide a small X-ray source 11 capable of selectively emitting several characteristic X-rays 21 having high monochromaticity without changing the X-ray generation point.

  Next, FIG. 14 shows a twelfth embodiment.

  In this embodiment, in the X-ray source 11 of the tenth embodiment, the target body 41 has different primary targets 18a, 18b, 18c, 18d and appropriate secondary targets 19a, 19b, 19c, 19d and appropriate. A plurality of sets of target portions 42a, 42b, 42c, and 42d in which the K edge filters 22a, 22b, 22c, and 22d are combined in an overlapping manner are provided.

  Then, the secondary targets 19a to 19d overlapped with the primary targets 18a to 18d and the K edge filters 22a to 22d rotate together to obtain a characteristic X-ray 21 having high monochromaticity with different energy. Since the driving unit is not provided outside the X-ray source 11, the X-ray source 11 can be placed close to the sample with higher reliability.

  In this way, it is possible to select and emit several characteristic X-rays 21 with high monochromaticity without changing the X-ray generation point, and it is possible to provide a small X-ray source 11 with high reliability.

  In each of the above embodiments, the movement of each of the target units 42a to 42d with respect to the electron beam incident position is not limited to rotation but may be a slide.

  Next, FIG. 15 shows a thirteenth embodiment.

  In this embodiment, the X-ray transmission window 13 is configured to be rotatable with respect to the vacuum vessel 12 in the configuration of the X-ray source 11 similar to that of the eighth embodiment. On the inner surface of the X-ray transmission window 13, a plurality of sets of target portions 42a, 42b, 42c in which different primary targets 18a, 18b, 18c, 18d and appropriate secondary targets 19a, 19b, 19c, 19d are combined in combination. , 42d is formed.

  And the target body 41 arrange | positions any one of several sets target part 42a-42d with respect to the electron beam incident position into which the electron beam 15 injects from the electron gun 14 by rotation of the X-ray transmissive window 13. The primary targets 18a to 18d of the target portions 42a to 42d arranged at the electron beam incident positions transmit and emit continuous X-rays 20 by the incidence of the electron beam 15, and the secondary targets 19a to 19d The characteristic X-rays 21 excited by the continuous X-rays 20 emitted from the primary targets 18 a to 18 d are transmitted and emitted from the X-ray transmission window 13.

  By selecting the target portions 42a to 42d, the characteristic X-ray 21 of the selected energy can be easily taken out, and the primary target 18a to 18d heated by the electron beam 15 is obtained by rotating the target body 41 integrally. There is an advantage that it is cooled by heat conduction to the X-ray transmission window 13 and the life is extended.

  As described above, it is possible to select and emit several characteristic X-rays 21 having high monochromaticity without changing the X-ray generation point, and it is possible to provide a small X-ray source 11 having a long lifetime.

  Next, FIG. 16 shows a fourteenth embodiment.

  In this embodiment, in the X-ray source 11 of the thirteenth embodiment, the target body 41 has different primary targets 18a, 18b, 18c, 18d and appropriate secondary targets 19a, 19b, 19c, 19d and appropriate A plurality of sets of target portions 42a, 42b, 42c, and 42d in which the K edge filters 22a, 22b, 22c, and 22d are combined in an overlapping manner are provided.

  Then, the secondary targets 19a to 19d overlapped with the primary targets 18a to 18d and the K edge filters 22a to 22d rotate together to obtain a characteristic X-ray 21 having high monochromaticity with different energy. , The primary targets 18a to 18d heated by the electron beam 15 are cooled by heat conduction to the X-ray transmission window 13, and there is an advantage that the life is extended.

  As described above, it is possible to select and emit several characteristic X-rays 21 having high monochromaticity without changing the X-ray generation point, and it is possible to provide a small X-ray source 11 having a long lifetime.

  Next, FIG. 17 shows a fluorescent X-ray analyzer 61 using the X-ray source 11 of each of the above embodiments.

  The fluorescent X-ray analyzer 61 irradiates the sample 62 with characteristic X-rays 21 emitted from the X-ray source 11, and the fluorescent X-rays 63 emitted by the excitation of the elements on the surface of the sample 62 through the collimator 64 are energy discrimination type. The X-ray detector 65 is used to perform elemental analysis.

  The X-ray source 11 applied to the fluorescent X-ray analyzer 61 has an energy spectrum mainly composed of characteristic X-rays (Kα rays, Kβ rays) 21 of the secondary targets 19a to 19d. It is possible to analyze the elemental composition by capturing the fluorescent X-rays 63 emitted by the elements on the surface of the sample 62 being excited.

  At this time, if the spectrum of the characteristic X-ray 21 to be excited is stored in advance in the analytical instrument and the relationship between the fluorescence signal / excitation intensity obtained thereby is grasped, the element on the surface of the sample 62 is determined from the fluorescence signal intensity. Quantitative analysis can be performed with high accuracy.

  Moreover, if the X-ray source 11 using the rotating primary targets 18a to 18d and the secondary targets 19a to 19d and the K edge filters 22a to 22d is applied, the target sample can be obtained without replacing the X-ray source 11. The energy of the characteristic X-ray 21 used for excitation can be selected according to the atomic number of 62 contained elements.

  Thus, the X-ray source 11 capable of efficiently emitting characteristic X-rays 21 can provide a high-resolution X-ray fluorescence analyzer 61.

  Next, FIG. 18 shows another example of the fluorescent X-ray analyzer 61.

  The fluorescent X-ray analyzer 61 includes a plurality of X-ray sources 11, irradiates a sample 62 with characteristic X-rays 21 emitted from any one of them, and passes through a collimator 64 to an energy discrimination type X-ray detector. In this configuration, the fluorescent X-ray 63 is captured at 65 and elemental analysis is performed.

  Then, similarly to the fluorescent X-ray analyzer 61, the fluorescent X-rays 63 emitted by the elements on the surface of the sample 62 excited by the characteristic X-rays (Kα rays, Kβ rays) 21 of the one X-ray source 11 to be used are used. It is possible to analyze the elemental composition, but by switching to the characteristic X-ray 21 from the other X-ray source 11, it is possible to analyze the elemental composition of a wide range of atomic numbers in a short time It becomes.

  Thus, the X-ray source 11 capable of efficiently emitting characteristic X-rays 21 can provide the fluorescent X-ray analyzer 61 that enables high-resolution elemental analysis in a short time.

It is explanatory drawing of the X-ray source which shows the 1st Embodiment of this invention. It is explanatory drawing explaining the X-ray conversion effect | action in the target part of an X-ray source same as the above. It is explanatory drawing of the X-ray source which shows the 2nd Embodiment of this invention. It is explanatory drawing explaining the X-ray conversion effect | action in the target part of an X-ray source same as the above. It is explanatory drawing of the X-ray source which shows the 3rd Embodiment of this invention. It is explanatory drawing of the X-ray source which shows the 4th Embodiment of this invention. It is explanatory drawing of the X-ray source which shows the 5th Embodiment of this invention. It is explanatory drawing of the X-ray source which shows the 6th Embodiment of this invention. It is explanatory drawing of the X-ray source which shows the 7th Embodiment of this invention. The 8th Embodiment of this invention is shown, (a) is explanatory drawing of an X-ray source, (b) is a perspective view of a secondary target body. The 9th Embodiment of this invention is shown, (a) is explanatory drawing of an X-ray source, (b) is a perspective view of a secondary target body and a filter body. The 10th Embodiment of this invention is shown, (a) is explanatory drawing of an X-ray source, (b) is a perspective view of a target body. It is explanatory drawing of the X-ray source which shows the 11th Embodiment of this invention. It is explanatory drawing of the X-ray source which shows the 12th Embodiment of this invention. It is explanatory drawing of the X-ray source which shows the 13th Embodiment of this invention. It is explanatory drawing of the X-ray source which shows the 14th Embodiment of this invention. It is explanatory drawing of the fluorescent X-ray-analysis apparatus using the X-ray source of this invention. It is explanatory drawing which shows the other example of the fluorescent X ray analysis apparatus of this invention. It is explanatory drawing of the conventional fluorescent X ray analyzer.

Explanation of symbols

11 X-ray source
12 Vacuum container
13 X-ray transmission window
14 electron gun
15 electron beam
18, 18a, 18b, 18c, 18d Primary target
19, 19a, 19b, 19c, 19d Secondary target
21 Characteristic X-ray
K edge filter as 22, 22a, 22b, 22c, 22d filter
31 Secondary target body
42a, 42b, 42c, 42d Target part
46 Rotating mechanism as moving mechanism
48 Filter body
61 X-ray fluorescence analyzer
62 samples
65 X-ray detector

Claims (15)

An electron gun that generates an electron beam;
A primary target that receives an electron beam from the electron gun and transmits X-rays to be emitted;
An X-ray source, comprising: a secondary target that is disposed so as to overlap the primary target, and transmits and emits characteristic X-rays excited by X-rays emitted from the primary target. . 2. A filter that attenuates Kβ rays among Kβ rays and Kα rays included in characteristic X-rays emitted from a secondary target and transmits Kα rays to transmit the rays is provided. X-ray source. A vacuum vessel having an X-ray transmission window;
An electron gun for generating an electron beam in the vacuum vessel;
A primary target disposed in the vacuum container and emitting an X-ray in a reflection direction when an electron beam is incident from the electron gun;
A characteristic X-ray which is arranged in the vacuum vessel so as to face the periphery around the primary target and is excited by the X-ray emitted from the primary target is reflected in the reflection direction toward the X-ray transmission window. An X-ray source comprising: a secondary target that emits. A vacuum vessel having an X-ray transmission window;
An electron gun for generating a ring-shaped electron beam in the vacuum vessel;
A primary target that is arranged in a ring shape in the vacuum vessel and emits an X-ray in a reflection direction when a ring-shaped electron beam is incident from the electron gun;
2 disposed in the vacuum chamber so as to face the center of the primary target, and emits characteristic X-rays excited by X-rays emitted from the primary target in a reflection direction toward the X-ray transmission window. An X-ray source comprising: A vacuum vessel having an X-ray transmission window;
An electron gun having a ground potential for generating an electron beam disposed in the vacuum vessel;
A primary target disposed in the vacuum container and emitting an X-ray in a reflection direction when an electron beam is incident from the electron gun;
A secondary target that is disposed at the position of an X-ray transmission window in the vacuum vessel and transmits and transmits characteristic X-rays excited by the X-rays emitted from the primary target. X-ray source. A filter that attenuates Kβ rays and transmits Kα rays out of Kβ rays and Kα rays included in the characteristic X-rays emitted from the secondary target is provided at the position of the X-ray transmission window. The X-ray source according to claim 3, wherein: An electron gun that generates an electron beam;
A primary target that receives an electron beam from the electron gun and transmits X-rays to be emitted;
A plurality of secondary targets that overlap the primary target and are movable with respect to the primary target X-ray generation position, and a secondary target arranged at the X-ray generation position is separated from the primary target. An X-ray source comprising: a secondary target body that transmits and emits characteristic X-rays excited by emitted X-rays. A plurality of filters that can move with respect to the X-ray generation position, and the filter disposed at the X-ray generation position is a Kβ line or a Kα line included in the characteristic X-rays emitted from the secondary target. The X-ray source according to claim 7, further comprising a filter body that attenuates Kβ rays and transmits Kα rays. A vacuum vessel having an X-ray transmission window;
An electron gun for generating an electron beam in the vacuum vessel;
An electron beam incident that is disposed in the vacuum vessel and has a plurality of sets of target portions in which different primary targets and secondary targets are combined in an overlapping manner, and an electron beam is incident on the plurality of sets of target portions from the electron gun. The primary target of the target unit arranged at the electron beam incident position is allowed to move with respect to the position, and transmits and emits X-rays by the incidence of the electron beam, and the secondary target is emitted from the primary target. A target body that transmits characteristic X-rays excited by the rays and emits them from the X-ray transmission window;
An X-ray source comprising: a moving mechanism for moving a target body in the vacuum vessel. It has a plurality of filters corresponding to a plurality of sets of target portions, is provided so as to be movable integrally with the target body outside the X-ray transmission window of the vacuum vessel, and corresponds to the target portion disposed at the electron beam incident position. The filter includes a filter body that attenuates Kβ rays among Kβ rays and Kα rays included in the characteristic X-rays emitted from the secondary target, and transmits the Kα rays and emits them. The X-ray source according to claim 9. A vacuum vessel having an X-ray transmission window;
An electron gun for generating an electron beam in the vacuum vessel;
Electrons that are arranged in the vacuum vessel and have a plurality of sets of target portions in which different primary targets, secondary targets, and filters are combined in an overlapped manner, and an electron beam is incident on the plurality of sets of target portions from the electron gun. The primary target of the target unit disposed at the electron beam incident position is movable with respect to the beam incident position, and transmits and emits X-rays by the incidence of the electron beam, and the secondary target is emitted from the primary target. Transmits and emits characteristic X-rays excited by X-rays, and filters attenuate Kβ rays and transmit Kα rays out of Kβ rays and Kα rays included in the characteristic X-rays emitted from the secondary target. A target body that emits from the X-ray transmission window;
An X-ray source comprising: a moving mechanism for moving a target body in the vacuum vessel. A vacuum vessel having an X-ray transmission window movably provided;
An electron gun for generating an electron beam in the vacuum vessel;
Provided in the X-ray transmission window in the vacuum vessel, and having a plurality of sets of target portions in which different primary targets and secondary targets are overlapped and combined, and by moving the X-ray transmission window, the plurality of sets of target portions are The electron gun is movable with respect to an electron beam incident position where the electron beam is incident, and the primary target of the target unit disposed at the electron beam incident position transmits and emits X-rays by the incidence of the electron beam. An X-ray source, comprising: a target body that transmits a characteristic X-ray excited by X-rays emitted from the primary target and emits the X-ray transmission window. A vacuum vessel having an X-ray transmission window movably provided;
An electron gun for generating an electron beam in the vacuum vessel;
The X-ray transmission window is provided in the X-ray transmission window, and has a plurality of sets of target portions obtained by combining different primary targets, secondary targets, and filters, and a plurality of sets of targets by moving the X-ray transmission window. The part is movable with respect to the electron beam incident position where the electron beam is incident from the electron gun, and the primary target of the target part arranged at the electron beam incident position transmits and emits X-rays by the incidence of the electron beam. The secondary target transmits and emits characteristic X-rays excited by the X-rays emitted from the primary target, and the filter emits Kβ rays and Kα rays included in the characteristic X-rays emitted from the secondary target. An X-ray source comprising: a target body that attenuates Kβ rays, transmits Kα rays, and emits them from the X-ray transmission window. The X-ray source according to claim 1, wherein the sample is irradiated with characteristic X-rays;
An X-ray fluorescence analyzer comprising: an X-ray detector that detects fluorescent X-rays generated by excitation of elements on the surface of the sample by irradiation with the characteristic X-rays. The X-ray fluorescence analyzer according to claim 14, comprising a plurality of X-ray sources that emit different characteristic X-rays as the X-ray source.

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