JP2017049098A - Fluorescence x-ray analysis device, fluorescence x-ray analysis method and computer program - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a fluorescence X-ray analysis device, fluorescence X-ray analysis method and computer program that enable discrimination of samples based on a measurement value even when a value range having sample discrimination degraded is present.SOLUTION: A fluorescence X-ray analysis device is configured to calculate concentration (a measurement value) of an element in a sample 6 on the basis of a measurement result of a fluorescence X-ray. A control device 1, in which two thresholds of the concentration of the element are predefined, is configured to determine whether the concentration is included in any of a first range less than a first threshold, a second range from the first threshold to a second threshold, and a third range exceeding the second threshold, and when the concentration of the element is included in the second range, accuracy of discriminating the sample 6 between a non-defect sample and a defect sample on the basis of the concentration falls. By determining that the concentration of the element is included in the second range, it can be made clear that the concentration is present in the range where accuracy of the sample discrimination falls. In this case, use of an analysis method other than a fluorescence X-ray analysis together with the fluorescence X-ray analysis may avoid a risk of discriminating the sample only with the fluorescence X-ray analysis method.SELECTED DRAWING: Figure 1

Description

  The present invention relates to a fluorescent X-ray analysis apparatus, a fluorescent X-ray analysis method, and a computer program for analyzing a sample based on detected fluorescent X-rays.

  The fluorescent X-ray analysis is sometimes used to measure a value according to the fluorescent X-ray intensity caused by a specific element contained in a sample, and to sort the sample based on the measured value. The measured value is the content or concentration of a specific element in the sample, the ratio of the fluorescent X-ray intensity with other elements, or the film thickness of the sample. For example, the concentration of a specific harmful element is compared with a specific threshold, and if the concentration is less than the threshold, the sample is determined to be non-defective, and if the concentration is equal to or higher than the threshold, the sample is determined to be defective. . In order to obtain a measurement value with high accuracy, it is necessary to lengthen the measurement time and reduce the error of the measurement value. However, an appropriate measurement time is unknown before measurement, and the measurement time may be too long in order to perform measurement with high accuracy. Therefore, Patent Document 1 discloses a technique for calculating an error of a measurement value based on a measurement result of fluorescent X-rays and comparing the measurement value including the error with a threshold value. For example, the measurement can be terminated when the maximum value of the measurement value considering the error is less than the threshold value, or when the minimum value of the measurement value is equal to or greater than the threshold value.

Japanese Patent Laid-Open No. 8-43329

  When a sample is separated using fluorescent X-ray analysis, there is a range of measured values that deteriorates the accuracy of separating the sample. For example, if a measurement value that is extremely above or below the threshold value is obtained, the sample can be sorted with high accuracy, but if a measurement value that is close to the threshold value is obtained, the sample is removed due to an error in the measurement value. The accuracy of sorting deteriorates. When a measurement value within a range that deteriorates the accuracy of the classification is obtained, it is dangerous to separate the sample only by the fluorescent X-ray analysis, and it is desirable to use another analysis method in combination. However, in the conventional method of comparing the measured value with the threshold value, it is difficult to sort the sample in consideration of the range of the measured value that deteriorates the accuracy of sorting.

  The present invention has been made in view of such circumstances, and the object of the present invention is to enable sample separation based on measurement values even when there is a range of values in which the accuracy of sample separation deteriorates. An object is to provide a fluorescent X-ray analysis apparatus, a fluorescent X-ray analysis method, and a computer program.

  The X-ray fluorescence analyzer according to the present invention calculates a measurement value according to the fluorescence X-ray intensity caused by a specific element, based on a measurement unit that measures fluorescence X-rays and a measurement result of the measurement unit. In a fluorescent X-ray analysis apparatus comprising a calculation unit and repeating measurement by the measurement unit and calculation by the calculation unit, a storage unit for storing a first threshold value and a second threshold value exceeding the first threshold value, and the calculation unit After calculating the measurement value, a confidence interval calculation unit for calculating a confidence interval of a predetermined confidence level of the measurement value, a first range including a value less than the first threshold, and the first threshold to the first threshold A determination unit that determines whether the confidence interval is included in any one of a second range including a value up to two thresholds and a third range including a value exceeding the second threshold. And the determination unit continuously in the same range multiple times If it is determined to contain a Lai section, characterized in that it comprises a determination unit for determining a range included the above measurements.

  In the X-ray fluorescence spectrometer according to the present invention, the storage unit stores the first threshold value and the second threshold value for each of a plurality of elements, and the calculation unit calculates the measurement value for each element. And the said determination part performs a process based on the said 1st threshold value and the said 2nd threshold value which are memorize | stored about each element.

  In the X-ray fluorescence spectrometer according to the present invention, the confidence interval is included in one or two specific ranges of the first range, the second range, and the third range for one element. And an end unit that terminates the processing in the calculation unit when the determination unit continuously determines a plurality of times.

  The fluorescent X-ray analysis method according to the present invention repeatedly measures fluorescent X-rays generated from a sample, and repeats measured values according to the fluorescent X-ray intensity caused by a specific element based on the fluorescent X-ray measurement results. And after calculating the measurement value, calculate a confidence interval of a predetermined confidence level of the measurement value, and a first range including a value less than a specific first threshold value, the first threshold value to the first threshold value. Whether the confidence interval is included in any one of the second range including a value up to a specific second threshold exceeding the threshold and the third range including a value exceeding the second threshold It is determined whether or not the range including the measurement value is determined when it is determined that the confidence interval is included in the same range consecutively a plurality of times.

  The computer program according to the present invention is a computer program for causing a computer to analyze a measurement result of fluorescent X-rays, repeatedly calculating a measurement value according to the fluorescent X-ray intensity caused by a specific element based on the measurement result, After the measurement value is calculated, a confidence interval of a predetermined confidence level of the measurement value is calculated, and a first range including a value less than a specific first threshold value exceeds the first threshold value from the first threshold value. Whether the confidence interval is included in any one of the second range including a value up to a specific second threshold and the third range including a value exceeding the second threshold. When the determination is made and it is determined that the confidence interval is included in the same range for a plurality of times in succession, the computer is caused to execute processing for determining the range in which the measurement value is included.

  In the present invention, the X-ray fluorescence analyzer determines two thresholds of measurement values according to the fluorescence X-ray intensity caused by a specific element in the sample, and the measurement obtained from the measurement result of the fluorescence X-rays Compare the value with two thresholds. In the X-ray fluorescence analyzer, the measurement value is included in any of a first range less than the first threshold, a second range from the first threshold to the second threshold, and a third range exceeding the second threshold. Determine whether. For example, when the range in which the measured value is clearly small is the first range, and the range in which the measured value is clearly large is the third range, the range in which the measured value is not too small and not too small and the sample separation accuracy is low is: Included in the second range. By determining that the measurement value is included in the second range, it is possible to clarify that the measurement value is in a range where the accuracy of classification is low.

  In the present invention, the X-ray fluorescence analyzer defines a first threshold value and a second threshold value for each of a plurality of elements, and executes calculation and determination of a measured value for each element. The sample can be sorted according to the measured values of a plurality of elements each having a different allowable amount.

  In the present invention, the X-ray fluorescence analyzer performs processing when a measured value of one element is included in one or two specific ranges of the first range, the second range, and the third range. Exit. If a specific range is a range in which the sample is determined to be defective according to the measured value of one element, such as a range where the concentration of harmful elements is too high, what is the measured value of the other element? Even if it exists, it is determined that the sample is defective. When the measured value of one element is included in a specific range, the processing of the fluorescent X-ray analyzer is terminated, so that unnecessary processing is omitted and the time required for sample separation is shortened.

  In the present invention, it is clarified that the measurement value relating to a specific element in the sample is in a range where the accuracy of fractionation of the sample is lowered, and in this case, an analysis method other than the fluorescent X-ray analysis is used in combination. to enable. Therefore, the present invention is excellent in that the sample can be separated based on the measurement value by the fluorescent X-ray analysis even when the measurement value by the fluorescent X-ray analysis has a range of values that deteriorate the accuracy of the sample separation. There is an effect.

It is a block diagram which shows the structure of a fluorescent X-ray analyzer. It is a block diagram which shows the structure of an information processing part. 3 is a conceptual diagram illustrating threshold values according to Embodiment 1. FIG. It is a block diagram which shows the hardware structural example inside a control apparatus. It is a flowchart which shows the procedure of the process which a fluorescent X-ray apparatus performs. It is a conceptual diagram which shows the threshold value which concerns on Embodiment 2. It is a conceptual diagram which shows the threshold value which concerns on Embodiment 3.

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 analyzer. The X-ray fluorescence analyzer includes an irradiation unit 4 that irradiates a sample 6 with X-rays, a sample holding unit 5 that holds the sample 6, and a detector 3 that detects fluorescent X-rays. A signal processing unit 2 that processes a signal is connected to the detector 3. The signal processing unit 2 and the irradiation unit 4 are connected to a control device 1 that controls the entire fluorescent X-ray analyzer and analyzes the measurement result of the fluorescent X-rays. The control device 1 controls the operations of the signal processing unit 2 and the irradiation unit 4.

  The irradiation unit 4 irradiates the sample 6 with X-rays, and the sample 6 generates fluorescent X-rays. The detector 3 detects fluorescent X-rays generated from the sample 6. In the figure, X-rays irradiated from the irradiation unit 4 to the sample 6 are indicated by broken line arrows, and fluorescent X-rays are indicated by solid line arrows. The detector 3 outputs a signal proportional to the detected fluorescence X-ray energy to the signal processing unit 2. The signal processing unit 2 counts each value signal output from the detector 3 and performs a process of generating a relationship between the fluorescent X-ray energy and the count number, that is, a fluorescent X-ray spectrum. The signal processing unit 2 outputs the generated fluorescent X-ray spectrum data to the control device 1. The irradiation unit 4, the detection unit 3, and the signal processing unit 2 correspond to the measurement unit in the present invention. Although FIG. 1 shows an example in which the sample 6 is a plate-like solid, the sample 6 may have any form. For example, the sample 6 may be a powder or a liquid. When the sample 6 is powder or liquid, the sample holder 5 is configured to hold a sample cell in which the sample 6 is stored.

  The control device 1 includes an information processing unit 11 that performs information processing, a storage unit 12 that stores data, and a display unit 13 that displays information. FIG. 2 is a block diagram illustrating a configuration of the information processing unit 11. The X-ray fluorescence analyzer quantifies the concentration of harmful elements contained in the sample 6, and performs a process of determining that the sample 6 is defective when the concentration of the harmful elements is high. The storage unit 12 stores a threshold value that is a determination criterion for determining that the sample 6 is defective. FIG. 3 is a conceptual diagram illustrating threshold values according to the first embodiment. The vertical axis in the figure indicates the concentration of the element. In the present embodiment, a first threshold value and a second threshold value exceeding the first threshold value are defined. The range of density values is divided into a range less than the first threshold, a range greater than or equal to the first threshold and less than or equal to the second threshold, and a range that exceeds the second threshold. The range less than the first threshold is an allowable range of the concentration of harmful elements, and the sample 6 is allowed to contain harmful elements having a concentration within the allowable range. The range exceeding the second threshold is a defective range in which the sample 6 is determined to be defective because the concentration of harmful elements is too high. The range from the first threshold value to the second threshold value is a boundary range corresponding to the boundary between the allowable range and the defective range. Since there is a certain degree of uncertainty in quantifying the concentration with an X-ray fluorescence spectrometer, when the concentration is included in the boundary range, the accuracy of separating a good sample from a defective sample based on the concentration value is low. Become. For this reason, when the concentration within the boundary range is obtained, it is desirable to sort the sample with higher accuracy by using another analysis method.

  The allowable range in the present embodiment corresponds to the first range in the present invention, the boundary range corresponds to the second range, and the defective range corresponds to the third range. The first threshold value and the second threshold value are stored in the storage unit 12 for each of the plurality of elements, and the distinction between the defect range, the boundary range, and the allowable range is also stored in the storage unit 12. The boundary range may be a range exceeding the first threshold and less than the second threshold, may be a range exceeding the first threshold and not more than the second threshold, and is greater than or equal to the first threshold and less than the second threshold. It may be a range. Further, the storage unit 12 may record a first threshold value and a second threshold value for each element and for each base material of the sample 6. The first threshold value and the second threshold value may be the same value for a plurality of elements.

  The storage unit 12 stores data of the measured spectrum of fluorescent X-rays. The information processing unit 11 includes a calculation unit 111 that calculates the concentration of each element in the sample 6 based on the fluorescent X-ray spectrum represented by the data stored in the storage unit 12. From the result, it has a confidence interval calculation unit 112 for calculating a confidence interval of concentration at a predetermined confidence level. Based on the first threshold value and the second threshold value stored in the storage unit 12, the information processing unit 11 has any one of the tolerance range, the boundary range, and the defect range as the confidence interval of the concentration calculated by the confidence interval calculation unit 112. It has the determination part 113 which determines whether it is contained in one range. When the determination unit 113 determines that the concentration confidence interval is not included in one range, the calculation unit 111 repeats the concentration calculation. When the determination unit 113 determines that the concentration confidence interval is included in one range, the information processing unit 11 determines that the concentration confidence interval is included in the same range twice consecutively. It has a number determination unit 114 for determining whether or not it has been performed. It should be noted that the number of times that the concentration confidence intervals should be included in the same range may be three or more. The storage unit 12 stores the number of times that the confidence interval of the concentration should be included in the same range continuously. The number determination unit 114 performs determination based on the number of times stored in the storage unit 12. When the number determination unit 114 determines that the determination unit 113 has not determined that the concentration confidence interval is included in the same range twice consecutively, the calculation unit 111 repeats the calculation of the concentration.

  In addition, the information processing unit 11 includes the element concentration when the determination unit 113 determines that the concentration confidence interval is included in the same range twice consecutively. Is determined in the range including the confidence interval of the concentration twice in succession. The information processing unit 11 includes a defect determination unit 116 that determines whether or not the range determined by the determination unit 115 is a defect range. If the range determined by the determination unit 115 is a defect range, the defect determination unit 116 An end unit 118 is provided for terminating the processing of the calculation unit 111 when the determination is made. The defect determination unit 116 performs determination based on the defect range stored in the storage unit 12. The information processing unit 11 includes an end determination unit 117 that determines whether or not to end the processing of the calculation unit 111 when the defect determination unit 116 determines that the range determined by the determination unit 115 is not a defect range. Yes. The end determination unit 117 determines not to end the processing of the calculation unit 111 when there is an element for which the determination unit 115 has not determined the range in which the concentration is included, and the calculation unit 111 repeats the calculation of the concentration. The end determination unit 117 determines to end the processing of the calculation unit 111 when there is no element in which the determination unit 115 has not determined the range in which the concentration is included, and the end unit 118 ends the processing of the calculation unit 111. . The storage unit 12 stores a maximum value of the measurement time. When the measurement time exceeds the maximum value stored in the storage unit 12, the end determination unit 117 determines to end the processing of the calculation unit 111, and the end unit 118 ends the processing of the calculation unit 111. After the end unit 118 ends the processing of the calculation unit 111, the information processing unit 11 outputs the analysis result to the display unit 13, and the display unit 13 displays the analysis result.

  FIG. 4 is a block diagram illustrating an exemplary hardware configuration inside the control device 1. The control device 1 is configured using a computer such as a personal computer. The control device 1 includes a CPU (Central Processing Unit) 14 that performs calculations, a RAM (Random Access Memory) 15 that stores temporary data generated along with the calculations, and a drive that reads information from a recording medium 100 such as an optical disk. Unit 16 and a non-volatile storage unit 12 such as a hard disk. The control device 1 also includes an operation unit 17 such as a keyboard or a mouse that accepts user operations, a display unit 13 such as a liquid crystal display, and an interface unit 18. The irradiation unit 4 and the signal processing unit 2 are connected to the interface unit 18. The CPU 14 causes the drive unit 16 to read the computer program 121 recorded on the recording medium 100 and stores the read computer program 121 in the storage unit 12. The computer program 121 is loaded from the storage unit 12 to the RAM 15 as necessary, and the CPU 14 executes processing necessary for the X-ray analyzer according to the loaded computer program 121. The computer program 121 may be downloaded from outside the control device 1. The control device 1 accepts the fluorescent X-ray spectrum data output from the signal processing unit 2 by the interface unit 18 and stores the data in the storage unit 12. Further, the control device 1 controls the operation of the irradiation unit 4 connected to the interface unit 18.

  The information processing unit 11 is realized by the CPU 14 executing necessary processing according to the computer program 121. The storage unit 12 stores threshold data 122 that records the first threshold and the second threshold. The first threshold value and the second threshold value are recorded in the threshold value data 122 for each of the plurality of elements, and the distinction between the defect range, the boundary range, and the allowable range is also recorded in the threshold value data 122. For example, the first threshold is 700 ppm and the second threshold is 1300 ppm. In the threshold data 122, a first threshold value and a second threshold value may be recorded for each element and for each base material of the sample 6. The threshold value data 122 may be stored in the storage unit 12 in advance, and the first threshold value and the second threshold value are input by the user operating the operation unit 17, and the input first threshold value and second threshold value are stored. The storage unit 12 may store the recorded threshold data 122.

  FIG. 5 is a flowchart showing a procedure of processing executed by the fluorescent X-ray apparatus. The CPU 14 loads the computer program 121 from the storage unit 12 to the RAM 15 and executes the following processing according to the loaded computer program 121. The X-ray fluorescence analyzer accepts an instruction to start measurement by operating the operation unit 17 by the user, and starts measuring X-ray fluorescence (S1). In the measurement of fluorescent X-rays, the control device 1 causes the irradiation unit 4 to irradiate the sample 6 with X-rays, the detection unit 3 detects fluorescent X-rays, the signal processing unit 2 creates a fluorescent X-ray spectrum, The control device 1 stores the fluorescent X-ray spectrum data in the storage unit 12. The X-ray fluorescence analyzer repeats the measurement of X-ray fluorescence. Moreover, the control apparatus 1 measures the measurement time of the fluorescent X-rays that have passed since the start of measurement. The control device 1 may measure the measurement time with the CPU 14 in accordance with the computer program 121, and may include hardware for measuring the measurement time.

  The CPU 14 selects one element from a plurality of elements designated in advance (S2). The plurality of elements are specified to measure the concentration, and any of them is a harmful element that is desirably not included in the sample 6. Information specifying a plurality of elements may be included in the computer program 121, stored in the storage unit 12 in advance, or input by operating the operation unit 17 by a user.

Next, the CPU 14 calculates the concentration of the selected element in the sample based on the spectrum of the fluorescent X-ray (S3). The concentration calculated in S3 corresponds to the measured value in the present invention. For example, the CPU 14 reads out spectrum data from the storage unit 12, identifies a peak attributed to the selected element in the spectrum, reads the intensity of fluorescent X-rays attributed to the element, and based on the read intensity, Calculate the concentration. Data for identifying a peak due to an element is stored in the storage unit 12 in advance. An example of a calculation formula for calculating the element concentration W, where W is the element concentration and I is the fluorescent X-ray intensity caused by the element, is the following expression (1).
W = a · I + b (1)

  Equation (1) is a calibration curve equation for calculating the element concentration W, and a and b in equation (1) are calibration curve constants. The calibration curve constants a and b may be included in the computer program 121 or may be stored in the storage unit 12 in advance. For example, in S3, the CPU 14 calculates the element concentration W according to the equation (1).

Next, the CPU 14 calculates the standard deviation of the calculated element concentration (S4). When the intensity of the fluorescent X-ray is expressed by the count number N, the theoretical standard deviation σ _{0 with} respect to the true value of the measured value of the fluorescent X-ray intensity is expressed by σ ₀ = (N) ^1/2 . The standard deviation σ ₀ is represented by σ ₀ = (I / t) ^1/2, where the fluorescent X-ray intensity I is the number of counts per second and the fluorescent X-ray measurement time is t. Here, the unit of I is cps (counts per second), and the unit of t is second. The standard deviation of the element concentration is theoretically a times the intensity of the fluorescent X-ray. Accordingly, when the standard deviation of the element concentration is σ, an example of a calculation formula for calculating the standard deviation σ of the element concentration is the following equation (2).
σ = a · σ ₀ = a · (I / t) ^1/2 (2)

  In S4, the CPU 14 calculates the standard deviation σ according to the equation (2). The CPU 14 may calculate σ by other methods. For example, the standard deviation σ may be calculated from the concentration value of the element calculated a plurality of times based on the repeatedly measured fluorescent X-ray measurement results.

  Next, the CPU 14 calculates a confidence interval of density at a predetermined confidence level (S5). For example, the element concentration calculated in S3 is W, and the standard deviation σ calculated in S4 is used to set the confidence interval of the confidence level of 99% to W-3σ or more and W + 3σ or less. In addition, for example, an average value of element concentrations calculated a plurality of times is set to Wm, and a confidence interval with a confidence level of 99% is set to Wm−3σ to Wm + 3σ. In S5, the CPU 14 calculates a minimum value and a maximum value within the concentration confidence interval. Note that the confidence interval may be calculated using another calculation formula. Alternatively, the confidence level may be calculated by a calculation formula corresponding to the confidence level with a confidence level other than 99%, such as a confidence level of 95%.

  Next, the CPU 14 determines whether or not the density confidence interval is included in any one of the allowable range, the boundary range, and the defect range (S6). In S6, the CPU 14 determines whether or not all of the confidence intervals are included in any range. Specifically, the CPU 14 determines that the confidence interval is included in one range when both the minimum value and the maximum value within the confidence interval are included in the same range, and the range including the minimum value When the range including the maximum value is different, it is determined that the confidence interval is not included in one range.

  If the concentration confidence interval is included in one range (S6: YES), the CPU 14 determines whether the concentration confidence interval is included in the same range twice in the last two determinations in S6. It is determined whether or not (S7). If the concentration confidence interval is included in the same range twice consecutively (S7: YES), the CPU 14 includes the concentration confidence interval in the range including the element concentration twice in succession. (S8). The CPU 14 stores information indicating the determined range in the RAM 15 or the storage unit 12 in association with the element. In S7, the number of times that the confidence interval of the concentration is continuously included in the same range may be three or more. Next, the CPU 14 determines whether or not the determined range is a defective range (S9). When the determined range is not the defective range (S9: NO), the CPU 14 determines whether or not there is an element whose concentration has not been measured among the plurality of designated elements (S10). If there is an element whose concentration has not been measured (S10: YES), the CPU 14 returns the process to S2. In this way, a plurality of elements are sequentially selected and the concentration is measured.

  When the confidence interval of concentration is not included in one range in S6 (S6: NO), or when the confidence interval of concentration is not included in the same range twice in S7 (S7: NO), The CPU 14 determines whether or not the measurement time elapsed from the start of measurement exceeds a predetermined maximum value (S11). The maximum value of the measurement time varies depending on the element, such as 100 seconds to 500 seconds. The maximum value of the measurement time is stored in advance in the storage unit 12 for each element, and the control device 1 measures the measurement time. When the measurement time is equal to or less than the maximum value (S11: NO), the CPU 14 returns the process to S3. In this way, the concentration calculation is repeated until the concentration confidence interval is included twice in the same range.

  When the range determined in S9 is a defective range (S9: YES), when there is no element whose concentration is not measured in S10 (S10: NO), or when the measurement time exceeds the maximum value in S11 (S11: YES), the CPU 14 ends the measurement of the fluorescent X-rays and the analysis of the elements (S12). In S <b> 12, the CPU 14 outputs a control signal to the irradiation unit 4 and the signal processing unit 2 via the interface unit 18, and ends the operations of the irradiation unit 4 and the signal processing unit 2. In this way, when the concentration of any element is included in the defect range, the sample 6 is defective, and the measurement and analysis are terminated. The measurement is also terminated when the measurement time is too long. CPU14 memorize | stores the analysis result of the sample 6 in the memory | storage part 12, and outputs it by displaying an analysis result on the display part 13 (S13). The analysis result indicates that the concentration of each of the plurality of elements is included in the allowable range or the boundary range. Alternatively, the analysis result indicates that the measurement is completed because the measurement time exceeds the maximum value. Alternatively, the analysis result includes an element whose concentration is included in the defective range, and thus it is indicated that the sample 6 is determined to be defective. CPU14 complete | finishes a process above. Note that the X-ray fluorescence analyzer can also perform processing on a single element. The X-ray fluorescence analyzer may output data indicating the analysis result to the outside. In addition, the X-ray fluorescence analyzer may execute part or all of the processes of S3 to S11 for a plurality of elements in parallel.

  As described above in detail, in the present embodiment, the X-ray fluorescence analyzer determines two element concentration threshold values, and compares the element concentration obtained from the X-ray fluorescence measurement result with the two threshold values. To do. Therefore, it is determined that the concentration of the element is included in the boundary range between the allowable range in which the concentration is clearly low and the inclusion of the element is allowed, and the defective range in which the concentration is clearly high and the sample 6 is determined to be defective. can do. When the concentration of the element is included in the boundary range, the accuracy of sorting the sample 6 using fluorescent X-ray analysis is reduced. Therefore, by determining that the concentration of the element is included in the boundary range, It can be clarified that the accuracy of sorting is low. If it becomes clear that the accuracy of classifying the sample 6 is low, the risk of classifying the sample 6 only by the fluorescent X-ray analysis can be avoided by using an analysis method other than the fluorescent X-ray analysis. On the other hand, when the element concentration is included in the allowable range or the defective range, the sample 6 can be separated with high accuracy. Therefore, according to the present embodiment, it is possible to perform sample separation based on the element concentration even when there is a range of values in which the measurement value by the fluorescent X-ray analysis deteriorates the accuracy of sample separation.

  Further, in the present embodiment, the X-ray fluorescence spectrometer calculates a concentration confidence interval in consideration of an element concentration error, and the concentration confidence interval is included in the same range a plurality of times in succession. The range in which the element concentration is included is determined. Thereby, the uncertainty of the density based on the measurement result of the fluorescent X-ray can be taken into consideration, and the measurement can be prevented from being repeated longer than necessary. In the present embodiment, the X-ray fluorescence analyzer determines a first threshold value and a second threshold value for each of a plurality of elements, and executes concentration calculation and determination for each element. The sample 6 can be separated according to the amounts of a plurality of elements having different allowable amounts.

  In this embodiment, the X-ray fluorescence analyzer defines a range exceeding the second threshold as a defective range in which the sample 6 is determined to be defective because the element concentration is too high. When the concentration is included in the defective range, the measurement of the fluorescent X-ray and the analysis of the element are finished. When the concentration of one element is in the defect range, such as when the concentration of one harmful element exceeds the second threshold, the sample 6 is defective regardless of the concentration of the other element. is there. For this reason, once it is determined that the concentration of one element is included in the defective range, it is not necessary to analyze another element for separating the sample 6. In the present embodiment, when it is determined that the concentration of one element is included in the defective range, the measurement of the fluorescent X-ray and the analysis of the element are finished, so that unnecessary measurement is omitted and the sample 6 is required to be separated. Time can be shortened.

  In the present embodiment, the information processing unit 11 is realized by the CPU 14 that executes processing according to the computer program 121. However, in the fluorescent X-ray analysis apparatus, part or all of the information processing unit 11 is hardware. The realized form may be sufficient. That is, some or all of the calculation unit 111, the confidence interval calculation unit 112, the determination unit 113, the number determination unit 114, the determination unit 115, the failure determination unit 116, the end determination unit 117, and the end unit 118 are configured by hardware. It may be.

<Embodiment 2>
In the present embodiment, an embodiment is shown in which an element that needs to contain a concentration in a sample within a specific range is analyzed by a fluorescent X-ray analyzer. The configuration of the X-ray fluorescence analyzer is the same as that of the first embodiment.

  FIG. 6 is a conceptual diagram showing threshold values according to the second embodiment. The vertical axis in the figure indicates the concentration of the element. A first threshold value and a second threshold value exceeding the first threshold value are defined, and a range less than the first threshold value and a range exceeding the second threshold value are defective ranges, and are not less than the first threshold value and not more than the second threshold value. The range is an acceptable range. The threshold shown in FIG. 6 is a threshold for analyzing a specific element in the alloy, for example. The concentration of certain elements in the alloy, such as the concentration of chromium in stainless steel, is inappropriate, whether it is too low or too high, and must be within a certain range with lower and upper limits. . For this reason, the range from the first threshold value to the second threshold value is an allowable range of the element concentration, and the range below the first threshold value and the range exceeding the second threshold value are defects in which the sample 6 is determined to be defective. It is a range.

  The allowable range in the present embodiment corresponds to the second range in the present invention, and the defective range corresponds to the first range and the third range. The first threshold value and the second threshold value are recorded in the threshold data 122 for each of the plurality of elements, and the distinction between the defective range and the allowable range is also recorded in the threshold data 122. The allowable range may be a range exceeding the first threshold and less than the second threshold, may be a range exceeding the first threshold and not more than the second threshold, and is greater than or equal to the first threshold and less than the second threshold. It may be a range.

  Similarly to the first embodiment, the X-ray fluorescence analysis apparatus according to the present embodiment executes the processes of S1 to S13 shown in the flowchart of FIG. In other words, the X-ray fluorescence analyzer calculates the concentration of each of a plurality of elements, calculates the confidence interval of the concentration, and the confidence interval is continuous twice in any of the allowable range and the two defective ranges. If it is included, the range in which the element concentration is included is determined. The analysis result indicates that the concentration of each of the plurality of elements is included in the allowable range. Alternatively, the analysis result indicates that the measurement is completed because the measurement time exceeds the maximum value. Alternatively, the analysis result includes an element whose concentration is included in the defective range, and thus it is indicated that the sample 6 is determined to be defective.

  As described above in detail, in the present embodiment, the X-ray fluorescence analysis apparatus includes the range below the first threshold and the second threshold among the concentration value ranges divided into three by the first threshold and the second threshold. A range exceeding the threshold value is defined as a defective range, and a range from the first threshold value to the second threshold value is defined as an allowable range. For this reason, the sample 6 in which the concentration of the element is too low or too high can be separated into defects, and the sample 6 in which the concentration of the element is not too low but not too high and is an acceptable value is separated into non-defective products. Can do. For example, quality control can be performed using a fluorescent X-ray analyzer for a material containing an element such as an alloy whose concentration needs to be included in a specific range.

  The X-ray fluorescence analyzer may be a combination of the first and second embodiments. For example, the threshold data 122 stored in the storage unit 12 defines a defect range, a boundary range, and an allowable range as shown in FIG. 3 for a certain element, and as shown in FIG. 6 for another element. It defines the distinction between defective ranges and acceptable ranges. The X-ray fluorescence analyzer performs the same processes as in the first embodiment for certain elements and performs the same processes as in the second embodiment for other elements by executing the processes of S1 to S13. In this embodiment, with respect to one sample 6, an element and a harmful element whose concentration needs to be included in a specific range can be analyzed with a fluorescent X-ray analyzer.

<Embodiment 3>
FIG. 7 is a conceptual diagram illustrating threshold values according to the third embodiment. The vertical axis in the figure indicates the concentration of the element. One threshold is set, a range less than the threshold is an allowable region, and a range greater than or equal to the threshold is a defective range in which the sample is determined to be defective. The configuration of the X-ray fluorescence analyzer is the same as that of the first embodiment. Similarly to the first embodiment, the X-ray fluorescence analysis apparatus according to the present embodiment executes the processes of S1 to S13 shown in the flowchart of FIG. That is, the X-ray fluorescence analyzer calculates the concentration for each of a plurality of elements, calculates a confidence interval for the concentration, and the confidence interval is included twice in either the allowable range or the defective range in succession. The range in which the element concentration is included is determined. When it is determined that the concentration of the element is included in the defective range, the measurement of the fluorescent X-ray and the analysis of the element are finished. The analysis result indicates that the concentration of each of the plurality of elements is included in the allowable range. Alternatively, the analysis result indicates that the measurement is completed because the measurement time exceeds the maximum value. Alternatively, the analysis result includes an element whose concentration is included in the defective range, and thus it is indicated that the sample 6 is determined to be defective.

  The X-ray fluorescence analyzer according to the present embodiment does not analyze other elements when the concentration of one element is included in the defective range even when a single threshold is set for each element. Then, the measurement of the fluorescent X-ray and the analysis of the element are finished. For this reason, also in this embodiment, unnecessary measurement by the fluorescent X-ray analyzer can be omitted, and the time required for sorting the sample 6 can be shortened.

  In the above first to third embodiments, the form in which the concentration is used as the measurement value corresponding to the fluorescent X-ray intensity caused by the specific element has been shown. However, the fluorescent X-ray analyzer is not a concentration other than the concentration. The form which calculates a value may be sufficient. The measured value may be the content of the element in the sample 6 or the film thickness of the sample 6. The measured value is a ratio of fluorescent X-ray intensity between a specific element and another element (for example, a ratio of fluorescent X-ray intensity caused by potassium and fluorescent X-ray intensity caused by chlorine). Also good. Moreover, in Embodiments 1-3, although the form which performs a fluorescent X ray analysis with respect to the sample 6 accommodated in the inside of a fluorescent X ray analyzer was shown, the fluorescent X ray analyzer is provided with the sample holding part 5. However, the fluorescent X-ray analysis may be performed by irradiating an external sample with X-rays. In the first to third embodiments, the control apparatus 1 mainly performs a necessary process using the computer program 121. However, the fluorescent X-ray analysis apparatus performs a process performed by the control apparatus 1. Some or all may be executed by hardware that does not use the computer program 121. Moreover, in Embodiment 1-3, although the form which performs control and analysis of each part of a fluorescent-X-ray-analysis apparatus collectively by the control apparatus 1 was shown, fluorescent-X-ray-analysis apparatus performs control and analysis separately. It may be executed by a computer.

DESCRIPTION OF SYMBOLS 1 Control apparatus 11 Information processing part 111 Calculation part 112 Confidence interval calculation part 113 Judgment part 115 Determination part 118 Termination part 12 Storage part 121 Computer program 122 Threshold data 13 Display part 14 CPU
15 RAM
DESCRIPTION OF SYMBOLS 100 Recording medium 2 Signal processing part 3 Detection part 4 Irradiation part 5 Sample holding part 6 Sample

Claims (5)

A measurement unit that measures fluorescent X-rays, and a calculation unit that calculates a measurement value according to the fluorescent X-ray intensity caused by a specific element based on the measurement result of the measurement unit, and the measurement by the measurement unit And a fluorescent X-ray analyzer that repeats the calculation by the calculation unit,
A storage unit for storing a first threshold value and a second threshold value exceeding the first threshold value;
A confidence interval calculation unit that calculates a confidence interval of a predetermined confidence level of the measurement value after the calculation unit calculates the measurement value;
A first range including a value less than the first threshold, a second range including a value from the first threshold to the second threshold, and a third range including a value exceeding the second threshold; A determination unit that determines whether or not the confidence interval is included in any one of the ranges;
A determination unit that determines a range in which the measurement value is included when the determination unit determines that the confidence interval is included in the same range in a plurality of times in succession. Line analyzer. The storage unit stores the first threshold value and the second threshold value for each of a plurality of elements,
The calculation unit calculates the measurement value for each element,
The fluorescent X-ray analysis apparatus according to claim 1, wherein the determination unit performs processing based on the first threshold value and the second threshold value stored for each element. For one element, the determination unit continuously determines a plurality of times when the confidence interval is included in one or two specific ranges of the first range, the second range, and the third range. The fluorescent X-ray analyzer according to claim 2, further comprising: an ending unit that terminates the processing in the calculation unit when the calculation is performed. Measure the X-ray fluorescence generated from the sample repeatedly,
Based on the measurement result of the fluorescent X-ray, repeatedly calculate the measured value according to the fluorescent X-ray intensity caused by the specific element,
After the measurement value is calculated, calculate a confidence interval of a predetermined confidence level of the measurement value,
A first range including a value less than a specific first threshold, a second range including a value from the first threshold to a specific second threshold exceeding the first threshold, and a value exceeding the second threshold Whether or not the confidence interval is included in any one of the third ranges in which is included,
An X-ray fluorescence analysis method characterized by determining a range in which the measured value is included when it is determined that the confidence interval is included in the same range in a plurality of consecutive times. In a computer program for causing a computer to analyze the measurement result of fluorescent X-rays,
Based on the measurement results, repeatedly calculate the measured value according to the fluorescent X-ray intensity caused by the specific element,
After the measurement value is calculated, calculate a confidence interval of a predetermined confidence level of the measurement value,
A first range including a value less than a specific first threshold, a second range including a value from the first threshold to a specific second threshold exceeding the first threshold, and a value exceeding the second threshold Whether or not the confidence interval is included in any one of the third ranges in which is included,
A computer program that causes a computer to execute a process of determining a range in which the measurement value is included when it is determined that the confidence interval is included in the same range in a plurality of times in succession.

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