JP2002195963A - X-ray spectroscope apparatus and x-ray analyzing apparatus - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide an X-ray spectroscope apparatus and an X-ray analyzing apparatus which do not impair compactness for a portable apparatus, and are suitable for analyzing light elements and a minute quantity of heavy elements. SOLUTION: The first and second semi-annular or annular light separating elements 3a, 3b for separating the X-ray 11 on an inner circumferential surface are coaxially provided. A limiting member 34 for shielding the X-ray which is not separated by the separating elements 3a, 3b is provided on the axis 35 of the separating elements 3a, 3b.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

The present invention relates to an X-ray spectrometer and an X-ray analyzer.

[0002]

2. Description of the Related Art Portable X-ray analyzers are required to be small and lightweight. Therefore, the structure of the apparatus is generally simplified, and it becomes difficult to analyze light elements and trace elements. X-ray fluorescence analysis is one type of X-ray analysis in which a sample is irradiated with primary X-rays from an X-ray source, and X-ray fluorescence generated from the sample is detected by an X-ray detector, and based on the detection result, Perform elemental analysis of the sample. As an apparatus for performing such analysis, an analyzer using a cylindrical spectroscopic element has been proposed (see Japanese Patent Application Laid-Open No. 11-23797). In this conventional technique, since a monochromatic primary X-ray is irradiated by a spectroscopic element, a specific trace element can be analyzed with high accuracy.

However, in the prior art, since the primary X-ray is made monochromatic, the primary X-ray does not include a spectrum having a low energy, and is not suitable for analyzing light elements such as Na and Mg.

[0004]

SUMMARY OF THE INVENTION The present invention has been made to solve the above-mentioned conventional problems, and its object is to analyze light elements or trace amounts of heavy elements without impairing the compactness as a portable type. To provide an X-ray spectrometer and an X-ray analyzer.

In order to achieve the above object, an X-ray spectrometer according to the present invention comprises a semi-annular or annular first and second spectral elements for dispersing X-rays on an inner peripheral surface, And a second spectral element are provided coaxially, and a limiting member that shields X-rays not split by the two spectral elements is provided on the axis of the two spectral elements.

When primary X-rays are emitted from an X-ray source provided on the axes of the two spectral elements to the spectral device, the primary X-rays are Bragg-reflected on the inner surfaces of the first and second spectral elements. Monochromatized, predetermined first and second monochromatic lights (not perfect monochromatic lights) are incident on the sample. Here, the two monochromatic lights have different wavelengths from each other, and are composed of high-energy X-rays and low-energy X-rays. Therefore, not only heavy elements but also light elements can be analyzed.

[0007] The spectroscopic element of the present invention is preferably formed in a barrel shape having an inner peripheral surface curved along the axis. As described above, since the effective area of the spectroscopic element is increased by the barrel shape, the X-ray intensity is remarkably large as compared with the prior art using the cylindrical spectroscopic element. Can be accurately analyzed.

As an X-ray analyzer to which the present invention is applied, in addition to an X-ray fluorescence analyzer that detects fluorescent X-rays generated from a sample and performs elemental analysis of the sample, diffraction by the sample is performed. The present invention can also be applied to an X-ray diffraction analyzer that knows the structure of the sample lattice from the X-ray diffraction angle.

[0009]

DESCRIPTION OF THE PREFERRED EMBODIMENTS One embodiment of the present invention will be described below with reference to the drawings. The portable X-ray fluorescence analyzer includes the measurement device 1 shown in FIG. 1, a measurement controller (not shown), a personal computer (arithmetic device), and the like.

In FIG. 1, a measuring device 1 includes a closed case 2
Inside the spectrometer 3, X-ray detector 5, mirror 6, and CCD
The camera 7 is housed. Primary X-rays 11 are emitted from the X-ray tube 10 to the sample on the sample stage 4 via the spectroscopic device 3. As shown in FIG. 2, the primary X-rays 11 excite the atoms of the sample 20 to generate fluorescent X-rays 12. X-ray fluorescence 1
2 is incident on the X-ray detector 5 and detected, and a well-known X-ray fluorescence analysis is performed by a personal computer.

As shown in FIG. 2, the X-ray tube 10 is a vertical (end window type) and air-cooled X-ray tube, in which a filament 13 is grounded, while a positive voltage is applied to a target 14. ing. For this reason, scattered electrons are less likely to be generated by the electrons 15 colliding with the target 14, so that the Be film, which is the window material 16, is less likely to be deteriorated by heat. Note that the tube voltage of the X-ray tube 10 can be set to an appropriate value.

The spectral device 3 includes a first spectral element 3a, a second spectral element 3b, a first slit 31, and a second slit 32.
And a limiting plate (limiting member) 34.

The two light-splitting elements 3a and 3b separate primary X-rays 11 on their inner peripheral surfaces. That is, each spectral element 3
Primary X-rays (monochromatic light) 11 which are monochromatic by Bragg reflection of only the primary X-rays 11 incident on the a and 3b at a predetermined incident angle
The sample 20 is irradiated with 1,112. Each of the spectral elements 3
a and 3b are formed in a barrel shape having a circular cross section orthogonal to the axis 35 as shown in FIG. 3A and having an inner peripheral surface curved along the axis 35 in FIG. The primary X-rays 11 can be Bragg-reflected over the entire circumference around the axis 35 and over a wide area covering substantially the entire length L of each of the spectral elements 3a and 3b. That is, each of the spectral elements 3a, 3b
Can separate the primary X-rays 11 emitted from the target 14 and condense them at a point O on the sample 20.
In addition, as the curve along the axis 35, an arc or a log spiral curve (Japanese Patent Laid-Open No. 6-82400,
(See No. 8) Various curves can be employed.

The two spectroscopic elements 3a and 3b are connected to a straight line connecting the target 14 of the X-ray tube 10 and the sample 20 by an axis 3
5 is assumed. In the present embodiment, the first spectral element 3a
Are arranged inside the second spectral element 3b. The first and second spectral elements 3a and 3b have different lattice spacings and irradiate the sample 20 with X-ray components having different energies of the primary X-rays 11 from each other.

For example, the first spectral element 3a is made of graphite (2d = 6.708 angstroms, θ = 5.019 °)
Or LiF (2d = 4.0273 angstroms, θ = 8.
378 °), the Pd-Kα ray (21.121 KeV
). On the other hand, the second spectroscopic element 3b employs graphite (θ = 40.62 °) or PET (2d = 8.76 angstroms, θ = 29.903 °) to obtain Pd.
Disperse the Lα ray (2.838 KeV).

The first and second slits 31 and 32 are annular, and are formed between the first spectral element 3a and the limiting plate 34 or the second spectral element 3b. The first slit 31 allows the primary X-rays 11 incident on the inner peripheral surface of the first spectral element 3a to enter at a predetermined incident angle, while the second slit 32 passes through the inner peripheral surface of the second spectral element 3b. Is passed through the primary X-rays 11 incident at an angle of incidence. The limiting plate 34
Is provided on the axis 35 and shields the primary X-rays 11 that are not split by the splitting elements 3a and 3b.

The CCD camera 7 shown in FIG. 1 is for confirming the position of the sample 20, and the captured image is displayed on a display of a personal computer. The closed case 2 of FIG. 1 is a closed container having pressure resistance, for example, so that the internal chamber can be maintained in a vacuum or He atmosphere.

The use of the present apparatus will be described. The first spectral element 3a shown in FIG.
Among the rays 11, the Pd-Kα rays 111 having high energy are separated and irradiated on the sample 20. On the other hand, the second spectral element 3b
In the primary X-rays 11, among the primary X-rays 11 emitted from the X-ray tube 10, the Pd-Lα rays 112 having low energy are separated and irradiated to the sample 20. Therefore, the sample 20 has two types of monochromatic primary X-rays 111 and 11 having greatly different energies.
2 is incident. Since the sample 20 is excited by the monochromatic primary X-ray 111 having a high energy, a trace amount of heavy element can be analyzed with high accuracy. On the other hand, since the sample 20 is excited by the monoenergized primary X-rays 112 having low energy, light elements can be analyzed with high accuracy. In addition, 2
Since the two monochromatic primary X-rays 111 and 112 have significantly different energies, they can be easily distinguished as a background.

Incidentally, as shown in FIG. 3A, the two light-splitting elements 3a and 3b may be divided into three parts.
There is no need to split. Further, the two spectral elements 3a and 3b do not need to be annular, and the second spectral element 3b in FIG.
The shape may be an annular shape such as a C-shape. Further, as shown in FIG. 3C, the two spectral elements 3a and 3b may be formed in a semi-annular shape. In addition, if the lattice spacing between the first light-splitting element 3a and the second light-splitting element 3b is largely changed, the energy to be split can be greatly changed, and thus it is not necessary to arrange them concentrically as shown in FIG. .

FIGS. 4 and 5 show a second embodiment. In the present embodiment, a total reflection collimator 33 is provided on the axis 35 of the two spectral elements 3a and 3b. Total reflection collimator 3
3 is the inside of the first spectral element 3a, each of the spectral elements 3a,
It is disposed substantially coaxially with 3b, and totally reflects and collects X-rays on the inner surface. The total reflection collimator 33 is preferably formed on the inner surface of a thin cylinder, but a solar slit in which a plurality of flat plates are arranged in parallel may be employed.

In this embodiment, the first and second limiting plates 34A and 34B shown in FIGS. 4 and 5 are provided. The first limiting plate 34A shown in FIG. 4 limits (blocks) the primary X-rays 113 (FIG. 5) emitted from the total reflection collimator 33, and the primary X-rays between the spectroscopic device 3 and the sample 20. Eleven paths are provided so as to be freely inserted and retracted. The first limiting plate 34A has a primary X-ray separated by the two light-splitting elements 3a and 3b.
A passage hole 36 that allows the passage of the lines 111 and 112 is provided.

On the other hand, the second limiting plate 34B shown in FIG. 5 limits (blocks) the primary X-rays 111 and 112 emitted from the spectroscopic elements 3a and 3b. The primary X-ray 11 is provided in the path so as to be freely inserted and retracted. The second limiting plate 34B has a passage hole 37 that allows the passage of the primary X-ray 113. One of the first limiting plate 34A and the second limiting plate 34B is selectively inserted between the sample 20 and the spectroscopic device 3.

[0023]

As described above, according to the present invention, since the first and second spectral elements are provided, two types of monochromatic primary X-rays can be obtained. In addition, since both the spectroscopic elements are semi-circular or annular, the intensity of monochromatic X-rays applied to the sample increases. Therefore, a trace amount of heavy element and / or light element can be accurately analyzed. Moreover, both spectroscopy elements are arranged coaxially,
Analysis of heavy elements and light elements can be performed by one analysis operation.

Further, if the inner peripheral surface of the spectroscopic element is formed in a barrel shape curved along the axis, the effective area of the spectroscopic element becomes large, so that the intensity of X-rays applied to the sample becomes extremely large, and Can be accurately analyzed.

Further, if the total reflection collimator is disposed substantially coaxially with the two spectroscopic elements inside the two spectroscopic elements and only the total reflection collimator is used, the solid angle of the X-ray incident on the sample can be reduced. X-rays can be focused on a minute portion. As a result, it becomes possible to analyze minute parts.

[Brief description of the drawings]

FIG. 1 is a schematic cross-sectional view showing a measuring device of a fluorescent X-ray analyzer according to a first embodiment of the present invention.

FIG. 2 is a schematic configuration diagram showing the optical system.

3A is a cross-sectional view showing first and second spectral elements, FIG. 3B is a cross-sectional view showing another example of the spectral element, and FIG.
FIG. 9 is a cross-sectional view showing still another example of the spectral element.

FIG. 4 is a schematic configuration diagram showing an optical system of a measurement device of the X-ray fluorescence spectrometer according to the second embodiment of the present invention.

FIG. 5 is a schematic configuration diagram showing the optical system.

[Explanation of symbols]

 1: Measuring device (analyzing device) 10: X-ray tube (X-ray source) 11: Primary X-ray 3: Spectroscopic device 3a: First spectroscopic element 3b: Second spectroscopic element 33: Total reflection collimator 34: Limiting plate (Limited) 34A, 34B: first and second limiting plates (limiting members) 35: axis 5: X-ray detector

Continued on the front page F term (reference) 2G001 AA01 AA09 BA04 CA01 DA02 EA02 EA03 EA09 EA20 GA01 HA09 HA13 KA01 NA16 PA07 SA02 SA10

Claims (5)

[Claims] 1. An image forming apparatus comprising: a semicircular or annular first and second light-splitting elements for separating X-rays on an inner peripheral surface; wherein the first and second light-splitting elements are provided coaxially; An X-ray spectrometer, wherein a limiting member that shields X-rays not split by the two spectroscopic elements is provided on an axis of the spectroscopic element. 2. The X-ray spectrometer according to claim 1, wherein both the spectroscopic elements are formed in a barrel shape having an inner peripheral surface curved along the axis. 3. The spectroscopic device according to claim 2, wherein a total reflection collimator for totally reflecting and condensing the X-rays on the inner surface is disposed substantially coaxially with the two spectral elements inside the two spectral elements. X-ray spectrometer. 4. An X-ray spectrometer according to claim 1, 2 or 3, an X-ray source provided on an axis of said two spectroscopic elements and emitting primary X-rays toward said X-ray spectrometer, X
An X-ray analyzer comprising: an X-ray detector that detects a ray. 5. An X-ray spectrometer according to claim 3, comprising: an X-ray source that emits primary X-rays toward the X-ray spectrometer; and an X-ray detector that detects X-rays from a sample. The limiting member is a primary X-ray incident on the total reflection collimator.
An X-ray analyzer that is provided so as to be insertable and retractable in a path of a primary X-ray emitted from a line or the total reflection collimator, and that is inserted in the path of the primary X-ray to shield the primary X-ray.