JP2010197229A - Fluorescent x-ray analyzer - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a miniaturizable fluorescent X-ray analyzer performing stably fluorescent X-ray analysis of a fine part included in a sample. <P>SOLUTION: In this fluorescent X-ray analyzer, a sample S on a sample placing surface 141 is irradiated with X-rays in a wide range in an uncollected state from an X-ray tube (X-ray irradiation means) 11, and only a fluorescent X-ray generated from a fine part in a detection range restricted by a poly-capillary X-ray half lens (detection range restriction means) 13 is detected by an X-ray detector (fluorescent X-ray detection means) 12. The optical axis of the poly-capillary X-ray half lens 13 is orthogonal to the sample placing surface 141, and the fine part of the sample S is surely irradiated with the X-ray regardless of the height of the sample S, and the fluorescent X-ray from the fine part is detected, to thereby perform stable fluorescent X-ray analysis. Further, since a focal size of the X-ray tube 11 is not required to be reduced, the fluorescent X-ray analyzer can be miniaturized easily. <P>COPYRIGHT: (C)2010,JPO&INPIT

Description

  The present invention relates to a fluorescent X-ray analyzer that irradiates a sample with X-rays and analyzes the fluorescent X-rays generated from the sample, and more specifically, fluorescent light that can analyze fluorescent X-rays from a minute portion in the sample. The present invention relates to an X-ray analyzer.

  X-ray fluorescence analysis irradiates a sample with X-rays generated using an X-ray tube, etc., detects fluorescent X-rays generated from the sample, and qualitatively analyzes elements contained in the sample from the spectrum of fluorescent X-rays And an analysis method for performing quantitative analysis. When analyzing a specific part included in the sample instead of analyzing the entire sample, or when examining the spatial distribution of elements contained in the sample, only the minute part in the sample is irradiated with X-rays, It is necessary to detect fluorescent X-rays generated from.

  As a method of irradiating a minute portion in a sample with X-rays, there is a method of narrowing the irradiated X-rays using a pinhole or the like. There is also a method of collecting irradiated X-rays using an X-ray collector. FIG. 6 is a schematic diagram showing a configuration example of a conventional fluorescent X-ray analyzer using an X-ray concentrator. The X-ray fluorescence analyzer includes an X-ray tube 51, an X-ray collector 52 and an X-ray detector 53. The X-ray detector 53 is an optical element that condenses incident X-rays while totally reflecting them internally. X-rays emitted from the X-ray tube 51 are incident on the X-ray collector 52, collected by the X-ray collector 52, and irradiated onto a minute portion on the sample. X-ray fluorescence generated in the sample is detected by the X-ray detector 53. By using the X-ray concentrator 52, the X-rays emitted by the X-ray tube 51 can be collected with a large solid angle and condensed. Therefore, compared to the method of narrowing the X-rays using a pinhole or the like, The intensity of irradiation X-rays can be increased and the sensitivity of elemental analysis can be improved.

  In order to perform X-ray fluorescence analysis of a large sample or a sample that cannot be sampled, a portable X-ray fluorescence analyzer has been developed. In Patent Literature 1, a probe including an X-ray tube, an X-ray concentrator, and an X-ray detector is configured to be portable, and X-ray irradiation and X-ray irradiation are performed with the probe pressed against a part of a sample. A portable X-ray fluorescence analyzer that detects X-ray fluorescence is disclosed.

Japanese Patent No. 3567185

  In a conventional fluorescent X-ray analyzer, the intensity of X-rays irradiated to a sample is reduced in a configuration in which irradiation X-rays are narrowed down using a pinhole or the like. It is necessary to use a wire tube. When a high-power X-ray tube is used, the risk of the fluorescent X-ray analyzer increases, and the fluorescent X-ray analyzer becomes large due to an electrical system that generates high output. In addition, in the fluorescent X-ray analyzer having the X-ray collector 52 as shown in FIG. 6, it is necessary to reduce the focal size of the X-ray in order to effectively collect the X-rays on a minute portion. The X-ray tube has a structure that generates X-rays by irradiating a metal target with an electron beam. To reduce the focal size of the X-ray, a mechanism for focusing the electron beam is used in the X-ray tube. Must be included. This increases the size of the X-ray tube. As described above, the conventional X-ray fluorescence analyzer that detects X-ray fluorescence from a minute portion in a sample has a problem that it is difficult to reduce the size. In particular, the portable fluorescent X-ray analyzer is not convenient because it is not sufficiently miniaturized.

  A conventional fluorescent X-ray analyzer as shown in FIG. 6 condenses X-rays on a sample by irradiating the sample with X-rays obliquely from above. In this state, if the height of the sample surface changes due to the sample thickness being different or the surface of the sample being uneven, the position where the X-rays are focused is shifted and the minute portion is Fluorescent X-rays cannot be detected. As described above, the conventional X-ray fluorescence analyzer has a problem that X-ray fluorescence analysis of a minute portion on a sample cannot be performed stably.

  The present invention has been made in view of such circumstances, and an object of the present invention is to provide a fluorescent X-ray that can be miniaturized while detecting the fluorescent X-ray from a minute portion included in the sample. An analyzer is provided.

  Another object of the present invention is to provide a fluorescent X-ray analyzer capable of stably performing a fluorescent X-ray analysis of a minute portion contained in a sample.

  An X-ray fluorescence analyzer according to the present invention comprises X-ray irradiation means for irradiating a sample with X-rays and X-ray fluorescence detection means for detecting fluorescent X-rays generated from the sample by X-ray irradiation. In the analyzer, it is an optical element that transmits fluorescent X-rays, and is arranged so that the transmitted fluorescent X-rays are detected by the fluorescent X-ray detection means, and it is predetermined among the fluorescent X-rays generated from the sample. By limiting the fluorescent X-rays that can be detected by the fluorescent X-ray detection means, the fluorescent X-rays from within the spatial range are allowed to pass and the fluorescent X-rays from outside the range are not allowed to pass. Detection range limiting means is provided, and the X-ray irradiation means is configured to irradiate the sample without condensing X-rays, and the detection range limitation means is arranged on the sample from the X-ray irradiation means to X A part of the irradiated range is included in the detection range. Characterized in that is arranged to be.

  In the present invention, the X-ray fluorescence analyzer limits the detection range that limits the spatial detection range of fluorescent X-rays that can be detected by irradiating the sample over a wide range without collecting the X-rays from the X-ray irradiation means. The means is arranged so that a part of the range irradiated with X-rays on the sample is included in the detection range. Of the fluorescent X-rays generated on the sample, only the fluorescent X-rays generated from the detection range limited by the detection range limiting means are detected. X-ray fluorescence analysis of a minute portion in the sample is possible without condensing the X-rays irradiated to the sample.

  The fluorescent X-ray analysis apparatus according to the present invention further includes a flat sample mounting surface for mounting a sample, and the detection range limiting means includes a line passing through the center of the limited detection range. It is arranged so as to be orthogonal to the placement surface.

  In the present invention, the X-ray fluorescence analyzer includes a sample placement surface for placing a sample, and the detection range limiting means is arranged so that the center line of the detection range is orthogonal to the sample placement surface. is there. Since the X-ray from the X-ray irradiation means is irradiated over a wide range, even if the height of the sample placed on the sample placement surface changes, the portion included in the detection range on the sample is irradiated with the X-ray. Then, fluorescent X-rays from this portion are detected.

  An X-ray fluorescence analyzer according to the present invention includes a housing that stores therein the X-ray irradiation unit, the fluorescent X-ray detection unit, and the detection range limiting unit, and the housing includes the X-ray irradiation unit. An opening through which X-rays to be emitted are emitted and fluorescent X-rays detected by the fluorescent X-ray detection means are incident; and a contact surface provided around the opening and capable of contacting an external object The detection range limiting means is arranged so that a line passing through the center of the limited detection range is orthogonal to a plane including the contact surface.

  In the present invention, in the portable fluorescent X-ray analyzer, an opening is formed in the housing, and a contact surface for contacting a large sample is provided around the opening. The center line of the detection range is arranged so as to be orthogonal to the plane including the contact surface. In a state where the contact surface is pressed against the sample larger than the opening, X-rays are irradiated from the X-ray irradiating means to the portion exposed to the inside of the fluorescent X-ray analyzer from the opening, X-ray fluorescence generated from a portion included in the detection range is detected.

  The X-ray fluorescence analyzer according to the present invention further includes means for limiting an irradiation range so that X-rays from the X-ray irradiation means are not irradiated to the detection range limiting means.

  In the present invention, the X-ray fluorescence analyzer limits the X-ray irradiation range so that X-rays from the X-ray irradiation means are not irradiated to the detection range limiting means, and X-rays are irradiated to the detection range limiting means. This prevents the detection of fluorescent X-rays generated.

  In the present invention, since it is not necessary to collect the X-rays irradiated to the sample in order to perform the fluorescent X-ray analysis of a minute portion in the sample, the X-ray irradiation means does not need to reduce the focal spot size. It is not necessary to incorporate a mechanism for focusing the electron beam inside. Accordingly, the X-ray irradiation means can be made smaller, the X-ray irradiation means can be brought closer to the sample than before, and the output of the X-ray irradiation means can be further increased while maintaining the intensity of the X-ray irradiated to the sample. Low output can be achieved. Thereby, a fluorescent X-ray analyzer can be reduced in size.

  In the present invention, since the fluorescent X-rays from a minute portion included in the detection range can be detected on the surface of the sample regardless of the height of the surface of the sample, the height of the surface of the sample Even if it is unspecified, it is possible to stably perform the fluorescent X-ray analysis of the minute portion contained in the sample.

  Further, in the present invention, in the portable X-ray fluorescence analyzer, the optical axis of the detection range limiting means is orthogonal to the plane including the contact surface that contacts the large sample. Even when there are protrusions or depressions, X-rays are irradiated to the minute portions included in the detection range on the sample, and fluorescent X-rays generated from the minute portions are detected. Therefore, even if there are irregularities on the surface of the sample, it is possible to stably perform a fluorescent X-ray analysis of a minute portion included in the sample.

  Furthermore, in the present invention, fluorescent X-rays that deteriorate the accuracy of fluorescent X-ray analysis by limiting the X-ray irradiation range so that X-rays from the X-ray irradiation unit are not irradiated to the detection range limiting unit. The present invention has an excellent effect that it does not occur and the accuracy of fluorescent X-ray analysis can be improved.

It is a block diagram which shows the structure of the fluorescent X-ray-analysis apparatus which concerns on Embodiment 1 of this invention. It is a schematic diagram which shows the detection range of a fluorescent X ray. It is a schematic diagram which shows the positional relationship of a polycapillary X-ray half lens and a sample. 6 is a schematic diagram illustrating an example of an appearance of a fluorescent X-ray analyzer according to Embodiment 2. FIG. FIG. 4 is a schematic diagram showing a part of the internal configuration of a fluorescent X-ray analyzer according to Embodiment 2. It is a schematic diagram which shows the structural example of the conventional fluorescent X-ray-analysis apparatus using an X-ray collector.

Hereinafter, the present invention will be specifically described with reference to the drawings showing embodiments thereof.
(Embodiment 1)
FIG. 1 is a block diagram showing a configuration of a fluorescent X-ray analysis apparatus according to Embodiment 1 of the present invention. The X-ray fluorescence analyzer includes an X-ray tube (X-ray irradiation means) 11 that emits X-rays, an X-ray detector (fluorescence X-ray detection means) 12, a polycapillary X-ray half lens (detection range limiting means) 13, A sample stage 14 on which the sample S is placed is provided. In the figure, X-rays are indicated by arrows. The sample stage 14 has a flat sample placement surface 141, and the sample S is placed on the sample placement surface 141. The X-ray tube 11 is disposed at a position where the central axis of the radiating X-ray is inclined with respect to the normal line of the sample placement surface 141. The X-ray fluorescence analyzer does not include an optical element for collecting the X-rays emitted from the X-ray tube 11, and the X-rays from the X-ray tube 11 are placed on the sample placement surface 141. The sample S is diffused and irradiated without being condensed. Thereby, the surface of the sample S is irradiated with X-rays over a wide range. From the portion of the sample S irradiated with X-rays, fluorescent X-rays are generated.

  The polycapillary X-ray half lens 13 is an optical element formed by bundling a large number of fine capillaries that guide light while totally reflecting incident X-rays inside, and the incident ends of many capillaries are arranged in a plane. X-rays incident on the end face are allowed to pass through and converted into parallel X-rays, and then emitted from the exit end face. As a whole, the polycapillary X-ray half lens 13 is formed in a tapered shape having an incident end face smaller than the exit end face. The polycapillary X-ray half lens 13 is configured to limit the spatial range of the X-ray incident source position that can be passed through to a predetermined size range. The X-ray detector 12 is disposed at a position for detecting fluorescent X-rays that are passed through and parallel by the polycapillary X-ray half lens 13. That is, the arrangement of the polycapillary X-ray half lens 13 and the X-ray detector 12 is such that, among the fluorescent X-rays generated on the sample S, the fluorescent X-rays passed by the polycapillary X-ray half lens 13 are X-ray detectors. The fluorescent X-rays detected by 12 and not allowed to pass through the polycapillary X-ray half lens 13 are arranged so that the X-ray detector 12 cannot detect them. Since the polycapillary X-ray half lens 13 limits the spatial range of the X-ray incident source that can pass through, the spatial detection range of fluorescent X-rays that can be detected by the X-ray detector 12 is reduced. It will be limited.

  FIG. 2 is a schematic diagram showing a fluorescent X-ray detection range. In the drawing, the boundary of the spatial detection range is indicated by a broken line, and the optical axis of the polycapillary X-ray half lens 13 which is a line passing through the center of the detection range is indicated by a one-dot chain line. The individual capillaries constituting the polycapillary X-ray half lens 13 pass only X-rays incident on the capillaries almost in parallel and do not allow other X-rays to pass. The polycapillary X-ray half lens 13 bundles a large number of capillaries with different relative inclinations for individual capillaries so that the incident end of each capillary faces a specific focal point outside the polycapillary X-ray half lens 13. It is configured. Since the X-rays incident on the incident end face of the polycapillary X-ray half lens 13 through the focal point shown in FIG. 2 are incident in parallel to any capillary, they pass through the polycapillary X-ray half lens 13. Similarly, X-rays incident along a straight line from an arbitrary point on a straight line passing through a point on the incident end of the polycapillary X-ray half lens 13 and the focal point are parallel to one of the capillaries. It passes through the X-ray half lens 13. Therefore, the fluorescent X-ray detection range that can pass through the polycapillary X-ray half lens 13 is a set of points on a straight line that passes through the point on the incident end of the polycapillary X-ray half lens 13 and the focal point. .

  The boundary of the fluorescent X-ray detection range is defined by a straight line connecting the capillary located at the outermost edge of the polycapillary X-ray half lens 13 and the focal point. As shown by the broken line in FIG. Eggplant. The spatial range inside the boundary forming the conical surface is the detection range. The size of the detection range is determined by the size of the incident end face of the polycapillary X-ray half lens 13 and the distance from the incident end face to the focal point. X-rays incident on the polycapillary X-ray half lens 13 from an arbitrary point included in the detection range pass through the polycapillary X-ray half lens 13. On the other hand, X-rays from outside the detection range cannot pass through the polycapillary X-ray half lens 13. Thus, the polycapillary X-ray half lens 13 limits the detection range of fluorescent X-rays that can be detected by the X-ray detector 12 as shown in FIG. The optical axis of the polycapillary X-ray half lens 13 passes through the focal point and passes through the center of the detection range.

  The polycapillary X-ray half lens 13 is arranged at a position and posture such that the focal point is located near the sample placement surface 141 and the optical axis is orthogonal to the sample placement surface 141. The focal point of the polycapillary X-ray half lens 13 may be, for example, on the sample placement surface 141 or may be at a position corresponding to the surface of the sample having an assumed thickness. Therefore, the position of the surface of the sample S placed on the sample stage 14 is close to the focal position of the polycapillary X-ray half lens 13, and a part of the surface of the sample S is included in the fluorescent X-ray detection range. The portion included in the detection range on the surface of the sample S includes a point where the optical axis of the polycapillary X-ray half-lens 13 intersects the surface of the sample S, and is a substantially point-like minute portion. The polycapillary X-ray half lens 13 receives fluorescent X-rays generated from a portion included in the detection range within the range irradiated with X-rays from the X-ray tube 11 on the sample S, and this fluorescent X-rays. Pass through. Therefore, the polycapillary X-ray half lens 13 allows fluorescent X-rays generated from a minute portion on the sample S to pass through. The X-ray detector 12 detects fluorescent X-rays that are passed through and parallel by the polycapillary X-ray half lens 13.

  The X-ray detector 12 has a configuration using a semiconductor detection element such as a Si element as the detection element, and outputs a current proportional to the detected energy of the fluorescent X-ray. An analysis processing unit 21 that analyzes the output current is connected to the X-ray detector 12. The analysis processing unit 21 receives the current output from the X-ray detector 12, counts the current of each current value, and the relationship between the fluorescent X-ray energy detected by the X-ray detector 12 and the count number, that is, the fluorescent X Performs processing to acquire line spectrum. A display unit 22 such as a liquid crystal display is connected to the analysis processing unit 21, and the analysis processing unit 21 performs processing for causing the display unit 22 to display the acquired spectrum of fluorescent X-rays. The analysis processing unit 21 may perform qualitative / quantitative analysis of the element that generates the fluorescent X-ray based on the acquired spectrum of the fluorescent X-ray.

  The X-ray fluorescence analyzer is provided with a collimator 15 in the vicinity of the radiation port from which the X-ray tube 11 emits X-rays. The collimator 15 is a part in which a hole for allowing X-rays radiated from the X-ray tube 11 to pass is formed, and limits the irradiation range of X-rays radiated from the X-ray tube 11. The collimator 15 is disposed at a position that limits the X-ray irradiation range so that X-rays emitted from the X-ray tube 11 are not irradiated onto the polycapillary X-ray half lens 13.

  When the sample S is placed on the sample placement surface 141, the X-ray tube 11 irradiates a wide range of the surface of the sample S, and is generated from a minute portion included in the detection range in the surface of the sample S. The fluorescent X-rays that have passed through the polycapillary X-ray half lens 13 cannot be transmitted through the polycapillary X-ray half lens 13. Since the X-ray detector 12 detects the fluorescent X-rays that have passed through the polycapillary X-ray half lens 13, only the X-ray fluorescence generated from a minute portion on the surface of the sample S is detected by the X-ray detector 12, and the fluorescence is detected. The X-ray analyzer can perform fluorescent X-ray analysis on a minute portion included in the sample S. That is, in the fluorescent X-ray analysis apparatus of the present invention, the sample S is placed on the sample placement surface 141 at a position where a specific portion in the sample S is included in the detection range, and the fluorescent X-ray analysis is performed. Qualitative / quantitative analysis of elements contained in a specific part in the sample S can be performed. If a mechanism for horizontally moving the sample S on the sample placement surface 14 or a mechanism for horizontally moving the polycapillary X-ray half lens 13 is provided, the X-ray fluorescence analyzer acquires the distribution of elements contained in the sample S. It is also possible.

  In the present invention, the X-ray emitted from the X-ray tube 11 is not collected, and the surface of the sample S is irradiated with X-rays from the X-ray tube 11 over a wide range, but the minute portion in the sample S is fluorescent. Allows X-ray analysis. Since the X-ray tube 11 does not collect radiated X-rays, it is not necessary to reduce the focal spot size and it is not necessary to incorporate a mechanism for focusing the electron beam inside. Therefore, in the present invention, the X-ray tube 11 can be made smaller than a conventional fluorescent X-ray analyzer that irradiates a sample with condensed X-rays, and the fluorescent X-ray analyzer can be downsized. Can do. Further, since the X-ray tube 11 is made smaller, the X-ray tube 11 can be brought closer to the sample stage 14 than in the past. As a result, the fluorescent X-ray analyzer can be further miniaturized, and the output of the X-ray tube 11 can be further reduced while maintaining the intensity of the X-ray irradiated to the sample S. By reducing the output of the X-ray tube 11, it is possible to reduce the size of an electric system (not shown) that supplies power to the X-ray tube 11 in order to generate X-rays, and further downsize the fluorescent X-ray analyzer. can do.

  FIG. 3 is a schematic diagram showing the positional relationship between the polycapillary X-ray half lens 13 and the sample S. Of the surface of the sample S, the portion included in the detection range is a portion where the fluorescent X-ray analysis is performed, and is centered on the point where the surface of the sample S and the optical axis of the polycapillary X-ray half lens 13 intersect. In position. The size of this portion is limited to a size determined by the distance from the focal point of the polycapillary X-ray half lens 13 to the surface of the sample S. FIG. 3 shows a case where the focal point of the polycapillary X-ray half lens 13 is located on the surface of the sample S. In this case, the portion where the fluorescent X-ray analysis is performed is dotted. The size is minimized.

  In FIG. 3, the surface of the sample S when the sample S having different heights is placed on the sample stage 14 is indicated by a broken line. The size of the portion on the surface of the sample S where the fluorescent X-ray analysis is performed is smaller as the surface of the sample S is closer to the focal point of the polycapillary X-ray half lens 13 and is larger as the surface of the sample S is farther from the focal point. As shown in FIG. 3, the polycapillary X-ray half lens 13 is arranged so that the optical axis is orthogonal to the sample placement surface 141, so that even if the height of the sample S changes, The position of the portion included in the detection range on the surface does not move in the horizontal direction. Since the X-ray tube 11 irradiates a wide range of the surface of the sample S, no matter what height the surface of the sample S is, the portion included in the detection range on the surface of the sample S includes: X-rays are irradiated, and the fluorescent X-rays generated from this portion pass through the polycapillary X-ray half lens 13 and are detected by the X-ray detector 12. That is, if the sample S is placed on the sample stage 14 so that a specific minute portion on the sample S is located directly below the polycapillary X-ray half lens 13, regardless of the height of the surface of the sample S, It is possible to reliably detect X-rays emitted from the minute part by irradiating the minute part on the sample S with X-rays. Therefore, even if the height of the surface of the sample S is unspecified due to variations in the thickness of the sample S or irregularities on the surface of the sample S, the fluorescent X-rays of a minute portion included in the sample S Analysis can be performed stably.

  In the present invention, the collimator 15 is provided so that the polycapillary X-ray half lens 13 is not irradiated with X-rays emitted from the X-ray tube 11. When X-rays are applied to the polycapillary X-ray half lens 13, fluorescent X-rays are generated on the surface of the polycapillary X-ray half lens 13, and the generated X-ray fluorescence is finally detected by the X-ray detector 12. There is a possibility that. This fluorescent X-ray is a fluorescent X-ray unique to the element contained in the polycapillary X-ray half lens 13, and causes a background signal unrelated to the sample S when performing the fluorescent X-ray analysis of the sample S. , Deteriorating the accuracy of fluorescent X-ray analysis. In the present invention, since the collimator 15 does not irradiate the polycapillary X-ray half lens 13 with X-rays, the X-ray fluorescence that deteriorates the accuracy of the X-ray fluorescence analysis is not generated from the polycapillary X-ray half lens 13, and the fluorescence It is possible to improve the accuracy of X-ray analysis.

  In the present embodiment, the form in which the fluorescent X-rays detected by the X-ray detector 12 are counted for each energy is shown. However, the present invention is not limited to this. A spectroscope that separates the rays may be further provided, and the fluorescent X-rays of each wavelength after the spectroscopy may be detected and counted.

(Embodiment 2)
In the first embodiment, a stationary fluorescent X-ray analyzer used in a laboratory or the like is shown. In the second embodiment, a portable fluorescent X-ray analyzer is shown. FIG. 4 is a schematic diagram showing an example of the appearance of the fluorescent X-ray analyzer according to the second embodiment. The X-ray fluorescence analyzer includes an X-ray tube 11, an X-ray detector 12, a polycapillary X-ray half lens 13, a collimator 15, an analysis processing unit 21, and a display unit 22 in a portable housing 3. It has a stored configuration. The housing 3 is formed with an opening 31 through which X-rays emitted from the X-ray tube 11 are emitted and fluorescent X-rays detected by the X-ray detector 12 are incident. Is provided with a planar contact surface 32. FIG. 4 shows a form in which an opening 31 and a contact surface 32 are formed at one end of a rectangular parallelepiped housing 3. Further, the X-ray fluorescence analyzer is provided with a trigger 33.

  The contact surface 32 is a surface for contacting a sample such as an industrial product or a building that is larger than the opening 31. For example, when the user holds the X-ray fluorescence analyzer by hand and presses the contact surface 32 against the sample, the contact surface 32 comes into contact with the sample. The X-ray fluorescence analyzer includes a sensor (not shown) that detects that the contact surface 32 is in contact with the sample. In a state where the sensor cannot detect that the contact surface 32 is in contact with the sample, The tube 11 has a configuration that cannot emit X-rays. For example, the X-ray fluorescence analyzer includes a shutter (not shown) for closing the opening 31. When the sensor cannot detect that the contact surface 32 is in contact with the sample, the shutter is closed. The shutter opens when the sensor detects that it is in contact with the sample. When the user operates the trigger 33 while the contact surface 32 is in contact with the sample, the X-ray tube 11 emits X-rays, and fluorescent X-ray analysis is executed.

  FIG. 5 is a schematic diagram showing a part of the internal configuration of the fluorescent X-ray analyzer according to the second embodiment. In the drawing, a state in which the fluorescent X-ray analyzer is pressed against the sample S larger than the opening 31 is shown, and X-rays are indicated by arrows. The contact surface 32 is formed in a planar shape, and the X-ray tube 11 is disposed at a position where the optical axis of the emitted X-ray is inclined with respect to the normal line of the plane including the contact surface 32. An optical element for condensing the X-rays emitted from the X-ray tube 11 is not provided, and the X-rays from the X-ray tube 11 are applied to the surface of the sample S over a wide range. Further, the polycapillary X-ray half lens 13 is disposed at a position and posture such that the focal point is located on a plane including the contact surface 32 and the optical axis is orthogonal to the plane including the contact surface 32. The X-ray detector 12 is disposed at a position where the polycapillary X-ray half lens 13 detects X-rays that are passed through and parallel to each other. The collimator 15 is disposed at a position that limits the X-ray irradiation range so that X-rays emitted from the X-ray tube 11 are not irradiated to the polycapillary X-ray half lens 13. An analysis processing unit 21 (not shown) is connected to the X-ray detector 12, and a display unit 22 (not shown) is further connected to the analysis processing unit 21.

  When the trigger 33 is operated in a state where the contact surface 32 is pressed against the sample S, the portion of the surface of the sample S exposed from the opening 31 to the inside of the fluorescent X-ray analyzer is X. X-rays are irradiated from the tube 11. Fluorescent X-rays generated from a minute portion included in the detection range on the surface of the sample S irradiated with X-rays pass through the polycapillary X-ray half lens 13. The X-ray detector 12 detects fluorescent X-rays that have passed through the polycapillary X-ray half lens 13, and the fluorescent X-ray analyzer performs fluorescent X-ray analysis. Thus, qualitative / quantitative analysis of elements contained in the sample S larger than the opening 31 can be performed using the fluorescent X-ray analysis apparatus according to the present embodiment.

  Also in the present embodiment, the X-ray emitted from the X-ray tube 11 is not collected, and the surface of the sample S is irradiated with X-rays from the X-ray tube 11 over a wide range, but the minute amount in the sample S is also reduced. Allows partial X-ray fluorescence analysis. Therefore, as in the first embodiment, the X-ray tube 11 can be reduced in size and output while enabling the X-ray fluorescence analysis of a minute portion in the sample S, and a portable X-ray fluorescence analyzer is provided. It can be made smaller. By reducing the size of the portable X-ray fluorescence analyzer, it becomes easy to carry the X-ray fluorescence analyzer, and it is possible to easily perform X-ray fluorescence analysis of large samples S such as industrial products or buildings. Become.

  In the present embodiment, the optical axis of the polycapillary X-ray half lens 13 is orthogonal to the plane including the contact surface 32 that contacts the sample S. Further, a minute portion included in the detection range in the surface of the sample S is at a position where the surface of the sample S intersects with the optical axis of the polycapillary X-ray half lens 13. For this reason, as in the first embodiment, even when the surface of the sample S has protrusions or depressions, a minute part on the sample S is reliably irradiated with X-rays, and the fluorescent X-rays generated from the minute part are Captured by the capillary X-ray half lens 13 and detected by the X-ray detector 12. Therefore, even if the surface of the sample S is uneven, it is possible to stably perform the fluorescent X-ray analysis of the minute portion included in the sample S.

  In the first and second embodiments, the polycapillary X-ray half lens 13 is used as the detection range limiting means in the present invention. However, the present invention is not limited to this, and the present invention limits the detection range. The form using another optical element as a means may be sufficient. For example, the detection range limiting means may be a monocapillary X-ray lens composed of a single capillary that guides incident X-rays while totally reflecting them inside, or a double pinhole collimator. Further, the shape of the detection range limited by the detection range limiting means is not limited to the cone shape shown in FIG. 2, but may be other shapes such as a column shape.

11 X-ray tube (X-ray irradiation means)
12 X-ray detector (fluorescent X-ray detection means)
13 Polycapillary X-ray half lens (detection range limiting means)
14 Sample table 141 Sample mounting surface 3 Housing 31 Opening portion 32 Contact surface S Sample

Claims (4)

In a fluorescent X-ray analyzer comprising: an X-ray irradiation means for irradiating a sample with X-rays; and a fluorescent X-ray detection means for detecting fluorescent X-rays generated from the sample by X-ray irradiation;
An optical element that allows fluorescent X-rays to pass therethrough, and is arranged so that the fluorescent X-rays that have passed therethrough are detected by the fluorescent X-ray detection means. Detection range limiting means for limiting the spatial detection range of fluorescent X-rays that can be detected by the fluorescent X-ray detection means by passing fluorescent X-rays from within the range and not allowing fluorescent X-rays from outside the range to pass through With
The X-ray irradiation means is configured to irradiate the sample without condensing X-rays,
The detection range limiting means is arranged so that a part of the range irradiated with X-rays from the X-ray irradiation means on the sample is included in the detection range. A flat sample mounting surface for mounting the sample;
The fluorescent X-ray analyzer according to claim 1, wherein the detection range limiting means is arranged so that a line passing through the center of the limited detection range is orthogonal to the sample placement surface. A housing for storing the X-ray irradiation means, the fluorescent X-ray detection means, and the detection range limiting means;
The housing is
An opening through which X-rays emitted by the X-ray irradiation means are emitted and fluorescent X-rays detected by the fluorescent X-ray detection means are incident;
A contact surface provided around the opening and capable of contacting an external object;
The fluorescent X-ray analysis apparatus according to claim 1, wherein the detection range limiting means is arranged so that a line passing through the center of the limited detection range is orthogonal to a plane including the contact surface. The fluorescent X-ray according to any one of claims 1 to 3, further comprising means for limiting an irradiation range so that X-rays from the X-ray irradiation means are not irradiated to the detection range limiting means. Analysis equipment.

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