JP3373824B2 - X-ray fluorescence analyzer - Google Patents

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a fluorescent X-ray analyzer for correcting a change in measured intensity over time.

[0002]

2. Description of the Related Art Conventionally, in a fluorescent X-ray analyzer for measuring the intensity of fluorescent X-rays generated by irradiating a sample with primary X-rays, the measured intensity of the same sample varies with time due to various causes. A so-called drift correction for correcting a change (drift) is performed regularly. For this drift correction, for example, if the X-ray intensities of all the standard samples used to create the calibration curve are measured again for each element, a great deal of time and effort is required for each correction. Therefore,
A drift-corrected sample is set for drift correction, and the reference X-ray intensity is measured in advance. When correcting, only the set drift-corrected sample is measured and the measured intensity at that time and the reference measured intensity are measured. The drift correction coefficient is calculated from
The drift correction coefficient is applied to the measured intensity of the sample to be analyzed for correction.

[0003]

This drift-corrected sample is a sample to be selected (hereinafter referred to as a selected sample, such as a standard sample whose composition is already known, or a drift-correction-dedicated sample whose measurement intensity is known even if the composition is unknown. From the target sample), the operator looks at the table of the content rate or measured intensity of the selected target sample,
Select and set each element. There are various selection methods,
In the so-called α method (one-point method), a selection target sample having a content rate or a measured intensity, for example, a value near the center of the distribution is selected as a drift correction sample for each element.
However, as described above, since there are many standard samples alone, the work of finding and selecting a sample to be selected having a value near the center of the distribution should be performed once for all elements. However, it also requires a lot of labor and time, and an operator's error is likely to occur, so that the analysis may be inaccurate. When samples of different varieties are analyzed, drift correction samples are selected and set for each varieties, and the problem becomes more serious.

The present invention has been made in view of the above conventional problems, and an object of the present invention is to provide an X-ray fluorescence analyzer capable of easily and appropriately selecting a so-called drift correction sample.

[0005]

In order to achieve the above object, the apparatus of claim 1 is an X-ray fluorescence analyzer for measuring the intensity of X-ray fluorescence generated by irradiating a sample with primary X-rays. Based on the contents stored in the storage means for storing the content rate or the measured intensity as a comparison value for a plurality of samples to be selected whose content rate for each element or the measured intensity by the device is known, And the plurality of selected pairs
Comparison in the distribution of comparative values for each element in the elephant sample
A one-point method selecting means for selecting, for each element, one sample to be selected whose value takes a value at a predetermined position as a drift correction sample serving as a reference for correcting the change over time of the measurement intensity in the apparatus. There is. Where the value at the given position
Can be set to a value near the center or to the maximum value. further,
For each element, there are provided registration means for storing the selected drift-corrected sample and its measured intensity, and registration display means for displaying the content stored in the registration means.

According to the apparatus of claim 1, the operator does not select a complex table by looking at a complicated table, but the drift-corrected sample is automatically processed by the so-called α method (1-point method) by the 1-point method selecting means or the like. Since it is selected, the drift correction sample can be easily and appropriately selected .

[0007] The apparatus of claim 2 is the apparatus of claim 1, based on the contents stored in the storage means, said double
The distribution of comparative values for each element in the sample to be selected.
And a two-point method selecting means for selecting, as a drift correction sample, one selection target sample having a maximum comparison value and one selection target sample having a minimum comparison value for each element, and the storage means. on the basis of the content, selects a drift correction sample by selecting the drift correction sample or the 2-point method selection means by comparing the relative distribution range of the ratio較値a predetermined spreading the 1-point method selection means And a selection method determining means for determining whether to perform each element .

According to the apparatus of claim 2 , the drift correction sample is further subjected to the α method (1-point method) or the 2-point method selecting means and the selecting method determining means in accordance with the relative distribution range of the comparison values. Since the so-called αβ method (two-point method) is automatically selected, the drift-corrected sample can be selected easily and more appropriately.

[0009] The apparatus of claim 3, in have your <br/> to claim 1 or 2, the comparison value of the drift correction samples selected by pre Symbol 1-point method or two-point method selection means within a predetermined range If a sample to be selected having an approximate comparison value is searched for each element and the sample to be selected is a drift-corrected sample instead of the drift-corrected sample selected by the one-point method or two-point method selection means, the whole drift-corrected sample In the case where the number of samples decreases, the sample is selected as a drift correction sample, and the sample number reducing means for canceling the selection by the one-point method or two-point method selecting means is provided.

According to the apparatus of claim 3 , further, the sample number reducing means automatically changes the selection of the drift-corrected samples within the range where the comparison values approximate, and the total number of the drift-corrected samples decreases. Since the labor and time required for measurement for each correction are reduced, the drift-corrected sample can be selected easily and more appropriately.

The apparatus according to claim 4 is the display means for confirmation according to any one of claims 1 to 3 , which displays the contents stored in the storage means so that the comparison value of the selected drift correction sample can be identified. When, the display operation of an operator based on the confirmation display means, extinguishing <br/> to take pre Symbol selection of confirmation display means display drift corrected samples for each element, the other selected target sample Element as a drift-corrected sample
And a selection changing means for selecting.

According to the apparatus of claim 4 , for automatic selection of the drift-corrected sample by the one-point method selecting means,
By operating the selection changing means based on the display of the confirmation display means, the operator can select another sample to be selected that seems more appropriate as the drift correction sample, so that the selection of the drift correction sample is simpler and more appropriate. Can be done.

According to a fifth aspect of the present invention, in the second aspect , the confirmation display means for displaying the contents stored in the storage means so that the comparison value of the selected drift correction sample can be identified, and the confirmation display means. the display operation of an operator based on the display means, cancel the selection by one of the selection means of decisions have been the 1-point method or two-point method selection means for each element,
Select the drift-corrected sample by the other selection means
And a decision changing means for changing the decision for each element .

According to the apparatus of claim 5 , in response to the automatic determination of the selecting means by the selecting method determining means, the operator operates the determination changing means on the basis of the display of the confirmation display means. The choice of drift-corrected sample can be made simpler and more appropriate, since the decision can be modified to select the drift-corrected sample by any other means of choice that seems appropriate.

[0015]

DETAILED DESCRIPTION OF THE INVENTION An apparatus according to an embodiment of the present invention will be described below. First, the configuration of this device will be described. As shown in the schematic view of FIG. 1, this apparatus is configured such that a sample 3 placed on a sample table 8 is connected to an X-ray source such as an X-ray tube from a primary X
This is an X-ray fluorescence analyzer for irradiating the X-rays 2 and measuring and analyzing the intensity of the X-ray fluorescence 4 generated by the detecting means 9. The detecting means 9 is composed of a spectroscopic element 5 that disperses the fluorescent X-rays 4 generated from the sample 3, a detector 7 that measures the intensity of the fluorescent X-rays 6 dispersed by the spectroscopic element 5, and the like. It is also possible to use a detector having a high energy resolution, such as an SSD, instead of the above.

This apparatus comprises the following storage means 11, selection method deciding means 12, decision changing means 13, and 1-point method selecting means 1.
The drift correction sample setting means 10 including the 4- and 2-point method selection means 15, the sample number reduction means 16, the selection change means 17, the registration means 18, the confirmation display means 19, and the registration display means 20 is provided. The drift-corrected sample setting means 10 can set a drift-corrected sample that serves as a reference for correcting the temporal change of the measurement intensity in this apparatus.

The storage means 11 compares the content ratios or measured intensities of a plurality of sample samples 3A to be selected, the content of each element of which is known, or the measurement intensity of which has been previously measured by this device. Store as a value. Here, the sample 3A to be selected is a candidate for the drift correction sample 3B. In addition to the standard sample whose composition used to create the calibration curve is known, the drift correction sample 3B is dedicated to drift correction where the measurement intensity by this device is known. A sample can be adopted. However, the comparison value stored in the storage means 11 is for comparison between the selection target samples 3A by the selection method determination means 12 described below,
At least for each element, it is necessary to standardize either the content rate or the measured strength.

The selection method determining means 12 compares the relative distribution range of the comparison value with a predetermined spread for each element based on the contents stored in the storage means 11, and selects the one-point method described below. It is determined whether the means 14 selects the drift correction sample 3B or the two-point method selection means 15 described later selects the drift correction sample 3B. Specifically, when the maximum value of the comparison value is, for example, 10% increase of the minimum value or more as a predetermined spread, when the maximum value of the comparison value is less than 10% increase of the minimum value for a certain element, It is decided by the 1-point method selecting means 14 to select the drift-corrected sample 3B, and if it is 10% or more, the 2-point method selecting means 15 is selected.
Determines to select the drift correction sample 3B. The determination is made in this way because, in general, the wider the relative distribution range of the comparison values, the more suitable the so-called αβ method (two-point method) for selecting two points of the drift correction sample 3B instead of one point. .

The one-point method selection means 14 is a storage means 11
1 of the selection target sample 3A in which the comparison value takes a value at a predetermined position in the distribution based on the content stored in
The point is selected as the drift correction sample 3B. In the so-called α method (one-point method) in which only one point is selected for such a drift-corrected sample 3B, it is appropriate to select the selection-target sample 3A in which the comparison value takes a value near the center of the distribution. Alternatively, there is a method in which it is appropriate to select the selection target sample 3A having the maximum value when the maximum content rate is 1% or less. Can be set to the value of or the maximum value. here,
As the selection target sample 3A in which the comparison value takes a value near the center of the distribution, the selection target sample having the content rate or the measurement intensity closest to the intermediate value (average value) between the maximum value and the minimum value (including the case where they match) 3A is searched.

On the other hand, the two-point method selection means 15 is based on the contents stored in the storage means 11, and one point of the sample 3A to be selected having the maximum comparison value and the minimum comparison value for each element. 2 and 1 point of the sample 3A to be selected are selected as the drift correction sample 3B. The selection is made in this way because, in the αβ method, it is appropriate to select the selection target sample 3A having the maximum comparison value and the selection target sample 3A having the minimum comparison value. In addition, in the one-point method and the two-point method selecting means 14 and 15, when there are a plurality of selection object samples 3A having the same comparison value, for example, the storing means 1
In the case of 1, the one stored earlier is selected based on a criterion such as preferentially selecting.

The number-of-samples reducing means 16 is 1 for each element.
The selection target sample 3A having a comparison value that approximates the comparison value of the drift correction sample 3B selected by the point method or two-point method selection means 14 and 15 within a predetermined range is searched, and the selection target sample 3A is searched for in the above 1 Point method or 2-point method selecting means 14, 1
If the drift correction sample 3B is selected instead of the drift correction sample 3B selected in 5, the drift correction sample 3B is selected as the drift correction sample 3B when the total number of drift correction samples 3B decreases, and the one-point method or two-point method selecting means 14, Cancel selection by 15. Here, the selection target sample 3A having a comparison value that approximates the comparison value of the selected drift correction sample 3B within a predetermined range is the selected drift correction sample 3B.
For example, the sample 3A to be selected has a comparative value within ± 1% (including the same comparative value) with respect to the comparative value of.

The confirmation display means 19 includes a CRT and the like,
The contents stored in the storage means 11 are displayed, for example, as shown in Table 1 below so that the comparison value of the selected drift correction sample 3B can be identified. Here, it is possible to identify that the comparison value is selected by displaying italics, but the comparison value and the background color thereof may be different from other colors so that the comparison value may be identified.

[0023]

[Table 1]

The decision changing means 13 has a confirmation display means 19
By the operator's operation based on the display of, the one-point method or the two-point method selecting means 14 and 15 which have been determined for each element cancel the selection, and the other selecting means cancels the drift-corrected sample 3B. Change the decision to select. The selection change means 17 cancels the selection of the drift correction sample 3B displayed on the confirmation display means 19 for each element by the operation of the operator based on the display of the confirmation display means 19, and selects another sample to be selected. 3A is selected as the drift correction sample 3B.

The registration means 18 stores, for each element, the drift correction sample 3B selected as described above and its measured intensity. The registration display means 20 also serves as the confirmation display means 19 and displays the contents stored in the registration means 18 as shown in Table 2 below.

[0026]

[Table 2]

Next, the operation of this device will be described.
First, the sample 3A to be selected is previously stored in the storage means 11.
The content of each element or the strength measured by this device, here, the strength measured by this device for each element is stored as a comparative value. This can also be used for preparing a calibration curve and the like, including data on a standard sample having a known composition. Then, for example, Si, Mn, P, S
The fact that the drift correction sample 3B is set when the analysis target sample 3C of a certain type including is set is input to the drift correction sample setting means 10 from the input means (not shown).
When inputting, the value at the predetermined position in the one-point method selecting means 14 is set to a value near the center, for example.

Then, when the maximum value of the comparison value is less than a predetermined increase of, for example, 10% of the minimum value for each element based on the contents stored in the storage means 11, the selection method determining means 12 Drift correction sample 3 by the 1-point method selection means 14
It is determined that B is selected, and if the increase is 10% or more, the two-point method selection unit 15 is determined to select the drift correction sample 3B. In response to the determination by the selection method determination means 12, the one-point method selection means 14 selects the sample to be selected whose comparison value is near the center for each element in charge based on the content stored in the storage means 11. One point 3A is selected as the drift correction sample 3B. On the other hand, the two-point method selecting means 15 also receives the decision of the selecting method deciding means 12, and based on the contents stored in the storing means 11, the selection object sample 3A having the maximum comparison value for each element in charge. 2 and one point of the selection target sample 3A having the minimum comparison value are selected as the drift correction sample 3B.

As described above, according to the apparatus of this embodiment,
It is not necessary for the operator to look at and select a complicated table, and the drift correction is performed according to the relative distribution range of the comparison values by the selection method determination means 12 and the one-point method, two-point method selection means 14, 15 and the like. Sample 3B is α method (1-point method) or αβ method (2-point method)
Is automatically selected, it is possible to easily and properly select the drift correction sample 3B.

Further, in this apparatus, the sample number reducing means 1
6 is the 1-point method or 2-point method selecting means 1 for each element
The selection target sample 3A having a comparison value that approximates the comparison value of the drift correction sample 3B selected by Nos. 4 and 15 within the predetermined range as described above is searched, and the selection target sample 3A is obtained by the one-point method or 2 If the drift correction sample 3B is used in place of the drift correction sample 3B selected by the point method selection means 14 and 15, the drift correction sample 3B is selected as the drift correction sample 3B when the total number of drift correction samples 3B decreases, and the one point method or 2 is used. The selection by the point method selection means 14 and 15 is canceled.

Specifically, referring to Table 1, with respect to Si, the No. E selection target sample 3A having a comparison value of 6.026 by the one-point method selection means 14 is the drift correction sample 3.
B, but instead of approximating 6.0
Sample No. 3A of No. C having a comparison value of 01 is
It is searched by the sample number reducing means 16 and selected as the drift correction sample 3B. As a result, the drift correction sample 3
The total number of B is from No. A, B, C, E to No.
It is reduced to three, A, B, and C. As described above, according to this apparatus, the drift correction sample 3 is within the range in which the comparison value approximates.
Since the selection of B is automatically changed and the number of the drift-corrected sample 3B as a whole is reduced, and the time and effort required for measurement for each correction are reduced, it is possible to select the drift-corrected sample 3B easily and more appropriately. it can.

After the input for setting the drift-corrected sample 3B, the drift-corrected sample 3B is automatically selected until this point. Further, the selected drift-corrected sample 3B and its measurement intensity are registered in the registration means 18. It may be stored automatically. Further, as described below, the operator can also check and correct the selected drift correction sample 3B.

First, as shown in Table 1 above, when the drift correction sample 3B is selected by the one-point method selection means 14 by the confirmation display means 19, the α method is displayed and two points are displayed. When the method is selected by the method selecting means 15, the αβ method is displayed. For example, when the operator moves the cursor with a mouse (not shown) or the like to display the α method under Si, the decision changing means 13 is selected. By Si
In, the selection of the No. C drift correction sample having the comparative value of 6.001 by the one-point method selection means 14 is canceled, and the drift correction sample 3B is selected again by the two-point method selection means 15, that is, the αβ method. The decision is changed to.

In response to this changed decision, the two-point method selecting means 15 selects the sample 3 to be selected having the maximum comparison value based on the contents stored in the storing means 11 at Si.
1 point of A and 1 of the sample 3A to be selected whose comparison value is the minimum value
And two points are selected as the drift correction sample 3B. After this, the sample number reducing means 16 may be further activated. In this way, as a result of the change of the determination, the drift correction sample 3
The selection of B is also changed so that the comparison value of the newly selected drift correction sample 3B can be identified.
9 is displayed. Specifically, the display of the comparative value of 6.001, which was selected by the one-point method selecting means 14 but was canceled, returns from italics to the standard typeface, and the comparative value of the newly selected drift correction sample 3B is changed. It is displayed in italics.

As described above, according to the apparatus of this embodiment,
For the automatic determination of the selection means 12 by the selection method determination means 13, the operator looks at the display of the confirmation display means 19 and operates the determination change means 13, so that it seems more appropriate based on experience. Drift correction sample 3
Since the determination can be changed to select B, the drift correction sample 3B can be selected easily and more appropriately. In this device, the confirmation display means 19
In order to facilitate the operator's judgment when viewing the display, as shown in Table 1 above, in comparison values for each element, the maximum value (H), the minimum value (L), and the value near the center (M ) Is added and displayed.

Furthermore, when the operator moves the cursor with a mouse (not shown) and clicks the display of the comparative value of 6.001 in Si with respect to the display of the confirmation display means 19 as shown in Table 1 above, the operator clicks the display. , Selection change means 1
7, the selection of the No. C drift-corrected sample 3B having the comparison value is canceled, and when the comparison value display of 6.251 is clicked, the No. A selection target sample 3A is drift-corrected instead. Selected as Sample 3B. In this way, when the selection of the drift correction sample 3B is changed,
The comparison value of the newly selected drift correction sample 3B is displayed on the confirmation display means 19 so that it can be identified. Specifically, it was selected before the change but was canceled 6.0.
The display of the comparison value of 01 returns from italics to the standard typeface, and the display of the newly selected comparison value of 6.251 is displayed in italics.

As described above, according to the apparatus of this embodiment,
Based on experience, the operator operates the selection changing means 17 while watching the display of the confirmation display means 19 in response to the automatic selection of the drift correction sample 3B by the one-point method selection means 14, 15, 16 or the like. Since another sample 3A to be selected, which seems more appropriate, can be directly selected as the drift correction sample 3B, the drift correction sample 3B can be selected easily and more appropriately.

As described above, after the operator confirms and corrects the selection of the drift correction sample 3B as necessary, for example, the "register" button displayed on the confirmation display means 19 is not shown. When the cursor is moved with a mouse or the like and clicked, the registration unit 18 stores the finally selected drift correction sample 3B and its measured intensity for each element.

Even if the comparison value is the content rate and the measured intensity in this device is unknown, the finally selected drift correction sample 3B can be stored in the registration means 18. However, since the reference measurement intensity is indispensable for use as the drift correction sample 3B, in this case, after the selected drift correction sample 3B is stored in the registration means 18, the drift correction samples 3B are The X-ray intensity is measured by this apparatus, and these measured intensities are stored in the registration means 18 as the reference measured intensity. For accurate drift correction, it is desirable to measure the X-ray intensity of the drift-corrected sample 3B at one time (at the same time), but if it is performed before selection, a large number of samples 3A to be selected are selected.
On the other hand, if it is performed after the selection, it is sufficient to perform only on the finally selected drift correction sample 3B (the selection is performed by the content ratio), and the burden of the measurement work is reduced.

The measured intensity I _S of the drift correction sample 3B stored in the registration means 18 serves as a reference, and when the drift correction is performed, the registration display means 2 as shown in Table 2 above, for example.
0 to display them, and registered drift correction sample 3
Only B is measured, and the drift correction coefficients α and β are obtained from the measured intensity I _M at that time and the reference measured intensity I _S as in the following equation (1) or (2) and (3). , The drift correction coefficients α and β are given by the following equation (4) or (5)
As described above, the measured intensity I C of the sample to be analyzed 3C is applied and corrected to obtain the corrected measured intensity I _C. The expressions (1) and (4) are based on the α method, and the expressions (2), (3) and (5) are based on the αβ method.
Is the case where there are two drift correction samples 3B for that element, that is, each drift correction sample 3 by the αβ method.
B is shown.

Α = I _S / I _M (1)

Α = (I _S1 −I _S2 ) / (I _M1 −I _M2 ) ... (2)

Β = I _S1 −αI _M1 (3)

I _C = αI (4)

I _C = αI + β (5)

[0046]

As described above in detail, according to the present invention, it is not necessary for the operator to look at and select a complicated table, and the drift correction sample can be selected by the 1-point method selecting means or the α method (1-point method). Method, etc., the drift-corrected sample can be easily and appropriately selected.

[Brief description of drawings]

FIG. 1 is a schematic diagram of an X-ray fluorescence analyzer according to an embodiment of the present invention.

[Explanation of symbols]

2 ... Primary X-ray, 3 ... Sample, 4 ... Fluorescent X-ray, 11 ... Storage means, 12 ... Selection method determining means, 13 ... Decision changing means, 14
... 1-point method selecting means, 15 ... 2-point method selecting means, 16 ... Sample number reducing means, 17 ... Selection changing means, 18 ... Registration means, 1
9 ... Confirmation display means, 20 ... Registration display means.

─────────────────────────────────────────────────── ─── Continuation of the front page (72) Inventor Takashi Matsuo 14-8 Akaoji-machi, Takatsuki City, Osaka Rigaku Denki Kogyo Co., Ltd. (56) Reference JP-A-7-49319 (JP, A) JP 60-205340 (JP, A) (58) Fields investigated (Int.Cl. ⁷ , DB name) G01N 23/223

Claims (5)

(57) [Claims] 1. A fluorescent X-ray analysis apparatus for measuring the intensity of fluorescent X-rays generated by irradiating a sample with primary X-rays, wherein a plurality of elements whose content rate by element or intensity measured by the apparatus is known. Storage means for storing the content rate or measured intensity as a comparison value for the sample to be selected, and the plurality of storage means based on the contents stored in the storage means .
Distribution of comparative values for each element in the selected sample
And a one-point method selecting means for selecting, for each element, one sample to be selected whose comparison value takes a value at a predetermined position as a drift correction sample serving as a reference for correcting the change over time of the measurement intensity in the apparatus. , A registration means for storing the selected drift-corrected sample and its measurement intensity for each element, and a registration display means for displaying the contents stored in the registration means are provided , and the value at the predetermined position is displayed near the center. Value or maximum value
Constant can fluorescent X-ray analyzer. 2. The plurality of the plurality of storage units according to claim 1 , based on the contents stored in the storage unit .
Distribution of comparative values for each element in the selected sample
And a two-point method selecting means for selecting, as a drift correction sample, one selection target sample having a maximum comparison value and one selection target sample having a minimum comparison value for each element, and storing in the storage means. on the basis of the content, selects a drift correction sample by selecting the drift correction sample or the 2-point method selection means by comparing the relative distribution range of the ratio較値a predetermined spreading the 1-point method selection means Do you have an element
An X-ray fluorescence analyzer provided with a selection method determining means for determining. 3. An apparatus according to claim 1 or 2, Selected samples before Symbol comparison value of the drift correction samples selected by one-point method or two-point method selection means has a comparison value that approximates within a predetermined range element If a drift-corrected sample is selected instead of the drift-corrected sample selected by the one-point method or two-point method selecting means, the sample to be selected is selected as a drift-corrected sample when the total number of drift-corrected samples decreases. An X-ray fluorescence analyzer equipped with sample number reducing means for selecting and canceling the selection by the one-point method or two-point method selecting means. 4. The confirmation display means for displaying the contents stored in the storage means so that the comparison value of the selected drift-corrected sample can be identified, and the confirmation display means according to any one of claims 1 to 3 . the display operation of an operator based on the display means, selecting for selecting the previous SL selection of drift correction samples displayed on the confirmation display means cancel each element, for each element of the other selection target sample as a drift correction sample An X-ray fluorescence analyzer provided with a changing means. 5. The method of claim 2, the stored contents in the storage means, a confirmation display means comparing values of the selected drift correction sample is displayed so as to identify, in view of the confirmation display means the operation of the basis was the operator cancels the selection by one of the selection means of decisions have been the 1-point method or two-point method selection means for each element, each element so as to select the drift correction sample by other selection means
An X-ray fluorescence analyzer provided with a decision changing means for changing the decision.