JP5811352B2 - X-ray fluorescence analyzer - Google Patents

Description

  The present invention relates to a fluorescent X-ray analyzer.

  A general-purpose fluorescent X-ray analyzer irradiates a sample with X-rays obliquely downward toward the center of the field of view of a camera for observing the sample while the sample is closely attached to the sample stage. A structure in which a line is measured by a detector installed on the opposite side is known (see Patent Document 1).

  Due to the variety of analysis requirements in recent years, there is a need to measure minute parts such as foreign matters in a sample. In that case as well, the measurement marker is usually displayed at the center of the camera field of view, and if the sample is moved so that a minute part such as a foreign object coincides with the measurement marker, the center of the camera field of view and the X-ray irradiation position coincide with each other. Can be measured.

  However, when measuring a sample with components mounted on a printed circuit board, the measurement surface of the sample cannot be brought into close contact with the sample stage. X-ray irradiation positions do not match.

  In addition, when a sample with components mounted on the measurement surface of the printed circuit board is placed on the sample table, the printed circuit board is not parallel to the sample table, and the center of the camera field of view and the X-ray irradiation position differ depending on the measurement location. The amount is different.

JP 2009-2795 A

  When measuring a sample that is not in close contact with the sample stage, the X-ray irradiation position is misaligned with the center of the sample observation camera. On the measurement surface that is not parallel to the sample stage, the amount of deviation varies depending on the measurement location, which is a further problem. Further, if the distance from the X-ray tube to the X-ray irradiation position of the sample changes, the irradiation intensity on the sample changes and affects the analysis result.

  In a fluorescent X-ray analyzer capable of changing a primary X-ray optical path length by irradiating X-rays from an oblique lower side of a sample and arranging a spacer between the sample table and the sample, between the sample table and the sample The actual X-ray irradiation position corresponding to the type of spacer to be installed or the presence or absence of the spacer is stored in advance.

  A spacer is installed between the sample table and the printed circuit board so that the sample table and the printed circuit board are parallel to each other. The user inputs the type of spacer currently used from the input device. According to the information, the position of the measurement marker is switched and displayed so as to coincide with the actual X-ray irradiation position according to the type or presence of the spacer.

  A mechanism that can automatically discriminate the type of the spacer regardless of the input by the user may be provided, and the position of the measurement marker may be switched and displayed more easily so as to coincide with the actual X-ray irradiation position.

  A fluorescent X-ray reference intensity corresponding to the type or presence or absence of a spacer placed between the sample stage and the sample is stored in advance. The user inputs the type of spacer currently used from the input device. According to the information, an accurate quantitative result is calculated with correction based on the relationship between the fluorescent X-ray reference intensity corresponding to the type of spacer and the fluorescent X-ray reference intensity when there is no spacer.

  An accurate quantitative calculation may be performed more simply by providing a mechanism that can automatically determine the type of spacer regardless of the input by the user.

  In the present invention, measurement of a sample that is in close contact with a normal sample stage and measurement of a sample that is difficult to be in close contact with a sample stage such as a printed circuit board can be performed simply and accurately by simply setting the presence or absence of a spacer or the type of spacer as a measurement condition. Thus, it is possible to provide a fluorescent X-ray analysis apparatus that can perform the above.

1 is a schematic configuration diagram of a fluorescent X-ray analyzer according to an embodiment of the present invention. The figure for demonstrating the actual use condition of the fluorescent X-ray-analysis apparatus based on the Example. The figure which shows the state which superimposed and displayed the measurement target marker on the sample image in the fluorescent X-ray-analysis apparatus based on the Example. The figure for demonstrating the recognition mechanism of the spacer kind of the fluorescent X-ray-analysis apparatus based on the Example.

  An embodiment of the present invention relating to a fluorescent X-ray analyzer capable of changing a primary X-ray optical path length by irradiating X-rays from obliquely below a sample and arranging a spacer between the X-ray source and the sample This will be described in detail below with reference to the drawings.

  FIG. 1 is a schematic configuration diagram of a fluorescent X-ray analyzer according to the present embodiment. The X-rays emitted from the X-ray tube 12 are focused to a predetermined diameter by the collimator 30 and irradiated to the fluorescent plate 40, the standard sample plate 39 or the sample 25 (see FIG. 2), and the fluorescent X-rays generated there are detected by the detector 13. To detect. The measurement part can be imaged by the sample observation camera 14 arranged below the sample. These are usually housed inside the X-ray shielding housing 10 and prevent leakage of X-rays to the outside.

  The signal from the detector 13 is digitally processed by the signal processing unit 16 and sent to the central control unit 19. The signal from the sample observation camera 14 is subjected to image processing by the image generation unit 17 and sent to the central control unit 19. The input unit 18 is usually a keyboard, and input information from the user is sent to the central control unit 19. The central control unit 19 calculates based on information from each unit, and stores information and calculation results in the storage unit. Further, the central control unit 19 displays the graphic information of the measurement target marker 31 (see FIG. 3) prepared in advance and the sample image information from the image generation unit 17 on the display unit 20.

  Several types of spacers having different lengths are prepared, and spacer numbers are assigned corresponding to the lengths. For example, a spacer length of 0 mm (no spacer) is defined as S0, a spacer length of 5 mm is defined as S1, and a spacer length of 10 mm is defined as S2.

  As shown in FIG. 1, X-rays emitted from the X-ray tube 12 are collimated by a collimator 30 in a state where a plurality of spacers 15 prepared between the sample stage 11 and the fluorescent plate 40 in the X-ray shielding housing 10 are inserted. An image of a fluorescent light emitted from the fluorescent plate is picked up with a predetermined diameter, and the fluorescent image is captured by a sample observation camera. If the spacer length used is 5 mm, the fluorescent position is stored in the storage unit 21 with the name of the S1 position and if it is 10 mm. .

  The fluorescent plate 40 in close contact with the sample stage 11 is irradiated with X-rays in the same state as described above, and an image of the fluorescent plate emitting fluorescence is captured by the sample observation camera 14 and the fluorescent position is stored in the storage unit 21 as the name of the S0 position. To do.

  As shown in FIG. 2, an X-ray fluorescence analysis is performed by arranging a spacer 15 between the actual sample 25, for example, a printed circuit board on which components are mounted, and the sample table 11 so that the sample 25 and the sample table 11 are parallel to each other. . At that time, the number of the used spacer is input as an analysis condition from the input unit 18 shown in FIG. For example, if the used spacer length is 5 mm, S1 is input.

  With the software of the central control unit 19, the measurement target marker 31 is superimposed on the sample image at the spacer number position previously stored in the storage unit 21 in accordance with the spacer number of the analysis condition, as shown in FIG. To display.

  FIG. 4 is a diagram for explaining an example of a mechanism for recognizing the type of spacer, and shows a cross section of the spacer, a cross section of the sample stage, and a recognition switch. The spacer is provided with a protrusion at a different position depending on the type, and a hole is made in the sample stage so that the protrusion of the spacer can be fitted. When the spacer is fitted into the sample stage, a recognition switch is installed at the lower part of the sample stage so as to be operated by the protrusion of the spacer.

  For example, the recognition switch A43 is activated when the spacer A41 is fitted, and the recognition switch B44 is activated when the spacer B42 is fitted. The switch information is sent to the central control unit 19 and is treated as spacer type information as is the input information from the input unit. If a spacer type recognition mechanism as shown in FIG. 4 is installed instead of inputting the spacer number, the object can be achieved more easily.

  Similar to the first embodiment, several types of spacers having different lengths are prepared, and spacer numbers are assigned according to the lengths.

  The X-ray emitted from the X-ray tube 12 is squeezed to a predetermined diameter by the collimator 30 with the spacer 15 having a length prepared between the sample stage 11 and the standard sample plate 39 inserted and detected at that time. The fluorescent X-ray reference intensity measured by the vessel 13 is stored in the storage unit 21 with the names of S1 intensity and S2 intensity corresponding to the spacer type using the reference.

  The standard sample plate in close contact with the sample stage 11 is irradiated with X-rays in the same state as described above, and the fluorescent X-ray reference intensity measured by the detector 13 at that time is stored in the storage unit 21 under the name of S0 intensity.

  An X-ray fluorescence analysis is performed by placing a spacer 15 between an actual sample 25, for example, a printed circuit board on which components are mounted, and the sample table 11 so that the sample 25 and the sample table 11 are parallel to each other. At that time, the number of the used spacer is input from the input unit 18 as an analysis condition. For example, if the used spacer length is 5 mm, S1 is input.

  At the time of quantitative calculation of the actual sample, the software of the central control unit 19 changes the X-ray optical path length by installing the spacer according to the relationship between the fluorescent X-ray reference intensity and the S0 intensity stored in advance in the storage unit 21 according to the spacer number. To correct the influence of, and calculate accurate quantitative results. For example, when spacer number 1 is used, the result obtained by multiplying the measurement result by (S0 intensity / S1 intensity) is an accurate quantitative result in which the influence of the change in the X-ray optical path length due to the spacer installation is corrected.

  If a spacer type recognition mechanism as shown in FIG. 4 is installed instead of inputting the spacer number, the object can be achieved more easily.

DESCRIPTION OF SYMBOLS 10 X-ray shielding housing | casing 11 Sample stand 12 X-ray tube 13 Detector 14 Sample observation camera 15 Spacer 16 Signal processing part 17 Image generation part 18 Input part 19 Central control part 20 Display part 21 Storage part 25 Sample (component is mounted) Printed circuit board)
30 Collimator 31 Measurement target marker 39 Standard sample plate 40 Fluorescent plate 41 Spacer A
42 Spacer B
43 Recognition switch A
44 Recognition switch B

Claims (4)

  In a fluorescent X-ray analyzer capable of changing the primary X-ray optical path length by irradiating X-rays from obliquely below the sample and arranging a spacer between the sample stage and the sample, corresponding to the type of the spacer Means for storing the irradiation position of the primary X-ray sample, input means for the user to specify the type of the spacer, imaging means for imaging the surface to be analyzed of the sample, and the currently designated spacer A fluorescent X-ray analysis apparatus comprising display means for displaying a marker indicating a primary X-ray irradiation position corresponding to a type superimposed on a sample image picked up by the image pickup means.   In a fluorescent X-ray analysis apparatus capable of changing a primary X-ray optical path length by irradiating X-rays from obliquely below a sample and arranging a spacer between the sample stage and the sample, the type of the spacer is identified. Means for storing the irradiation position of the primary X-ray corresponding to the type of the spacer, imaging means for imaging the surface to be analyzed of the sample, and the primary X-ray corresponding to the type of the spacer currently used A fluorescent X-ray analysis apparatus comprising display means for displaying a marker indicating an irradiation position in a superimposed manner on a sample image picked up by the image pickup means. It is possible to change the primary X-ray optical path length by irradiating X-rays from obliquely below the sample and arranging one type of spacer selected from a plurality of types of spacers having different lengths between the sample stage and the sample. In a possible X-ray fluorescence analyzer, a means for storing a fluorescent X-ray reference intensity corresponding to a plurality of types of spacers having different lengths , and a user specifying the type of the selected one type of spacer the input means, the fluorescent X-ray analysis apparatus characterized by comprising a calculating means for quantifying calculated based on X-ray fluorescence reference intensity corresponding to the type of the designated spacers. It is possible to change the primary X-ray optical path length by irradiating X-rays from obliquely below the sample and arranging one type of spacer selected from a plurality of types of spacers having different lengths between the sample stage and the sample. In a possible X-ray fluorescence analyzer, a means for identifying the type of one selected spacer, a means for storing fluorescent X-ray reference intensities corresponding to a plurality of types of spacers having different lengths , A fluorescent X-ray analysis apparatus comprising an operation means for quantitatively calculating based on a fluorescent X-ray reference intensity corresponding to the type of the identified spacer being used.