Spectrometer device

Abstract

The present application relates to a kind of spectrometer device, including first displacement stage, second displacement stage, sample stage, first displacement stage is located on position sensitive detector, it is used to make position sensitive detector move along X, Y and Z direction;Second displacement stage is equipped with multiple third displacement stages, and second displacement stage is used to make each third displacement stage move along Z direction;Each third displacement stage is equipped with a crystal, and is used to make the crystal on it move along X direction and rotate around Z axis;Sample stage is equipped with sample holder, and sample holder is used to fix sample;Position sensitive detector is located above sample holder, each crystal is arranged around sample holder, and each crystal is columnar bending crystal;Sample is used to receive incident X-ray, and generate fluorescence under the irradiation of incident X-ray, and fluorescence is transmitted to each crystal and Bragg diffraction occurs on each crystal, and position sensitive detector is used to receive the diffraction light of each crystal, to obtain fluorescence image, and there is the light spot of the diffraction light of each crystal in fluorescence image.

Description

TECHNICAL FIELD

[0001] The present application relates to the technical field of electron-optical instrument, more particularly to a spectrometer device. BACKGROUND

[0002] High energy resolution fluorescence detected X-ray absorption fine structure (HERFD-XAFS) is a high-resolution absorption spectroscopy technique based on synchrotron X-ray, which significantly improves the energy resolution by optimizing the fluorescence signal detection method, so as to more accurately reveal the electronic structure and local atomic arrangement information of the material.

[0003] With the help of high-resolution emission spectrometer or absorption spectrometer, in the emission spectrum test, a certain specific fluorescence spectrum is selected, recorded and integrated, the incident X-ray energy is adjusted to cover the XANES (X-ray absorption near edge structure) or EXAFS (extended X-ray absorption fine structure) range, and high-resolution fluorescence detected X-ray absorption fine structure (HERFD-XAFS) can be obtained. However, the existing spectrometer device has low collection efficiency for fluorescence signals, most of the fluorescence photons cannot be effectively detected, resulting in weak signal intensity and poor signal-to-noise ratio; especially in the case of low concentration sample or weak fluorescence signal, this problem is more prominent, which seriously affects the quality of the spectrum and the analyzability of the data.

[0004] Therefore, the skilled in the art urgently needs a spectrometer device with higher collection efficiency to accurately obtain the fine structure information of the material. SUMMARY

[0005] The present application aims to provide a spectrometer device which can greatly improve the solid angle and thus improve the signal collection efficiency.

[0006] In order to achieve the above purpose, the present application provides a spectrometer device, comprising a first displacement table, a second displacement table, a sample table and a position sensitive detector, the position sensitive detector is arranged on the first displacement table, the first displacement table is used for moving the position sensitive detector in X, Y and Z directions; a plurality of third displacement tables are arranged on the second displacement table, the second displacement table is used for moving each third displacement table in Z direction; a crystal is arranged on each third displacement table, each third displacement table is used for moving the crystal thereon in X direction and rotating around Z axis; a sample holder is arranged on the sample table, the sample holder is used for fixing a sample; the position sensitive detector is located above the sample holder, each crystal is arranged around the sample holder, each crystal is a cylindrical bent crystal; the sample is used for receiving incident X-ray and generating fluorescence under the irradiation of the incident X-ray, the fluorescence is transmitted to each crystal to occur Bragg diffraction on each crystal, and the position sensitive detector is used for receiving the diffraction light of each crystal to obtain a fluorescence image, wherein the diffraction light of each crystal forms a spot in the fluorescence image.

[0007] Optionally, the crystals are arranged along a circumferential direction of an arc.

[0008] Optionally, different positions of each crystal correspond to different Bragg angles, and the Bragg angles of the different positions of each crystal are arranged to change with movement of the position-sensitive detector along the Z direction and / or movement of the crystals along the Z direction.

[0009] Optionally, the size and brightness of the light spot formed by the diffraction light of each crystal on the position-sensitive detector change with movement of the crystal along the X direction, and the lateral position of the light spot formed by the diffraction light of each crystal on the position-sensitive detector changes with rotation of the crystal around the Z axis.

[0010] Optionally, the light spots formed by the diffraction light of the crystals on the position-sensitive detector are located at the same position or at different positions but in an optimal state.

[0011] Optionally, the first displacement stage includes a first X-direction moving stage, a first Y-direction moving stage, and a first Z-direction moving stage, the first Y-direction moving stage is arranged on the first X-direction moving stage, the first Z-direction moving stage is arranged on the first Y-direction moving stage, the position-sensitive detector is arranged on the first Z-direction moving stage, the first X-direction moving stage is configured to move the first Y-direction moving stage along the X direction, the first Y-direction moving stage is configured to move the first Z-direction moving stage along the Y direction, and the first Z-direction moving stage is configured to move the position-sensitive detector along the Z direction.

[0012] Optionally, each third displacement stage includes a second X-direction moving stage and a Z-direction rotating stage, the Z-direction rotating stage is arranged on the second X-direction moving stage, the crystal is arranged on the Z-direction rotating stage, the second X-direction moving stage is configured to move the Z-direction rotating stage along the X direction, and the Z-direction rotating stage is configured to rotate the crystal around the Z axis.

[0013] Optionally, an arc-shaped support is arranged on the second displacement stage, and each third displacement stage is arranged on the arc-shaped support in sequence; each crystal is fixed to the third displacement stage by a crystal support.

[0014] Optionally, the crystals are five in number, each crystal has a radius of curvature of 250 mm, and the crystal has a crystal surface size of 100 mm x 25 mm.

[0015] Optionally, the calibration method of the fluorescence image includes:

[0016] detecting a characteristic spectral line of the standard sample to obtain a fluorescence image of the characteristic spectral line of the standard sample;

[0017] acquiring a pixel position of the characteristic peak of the standard sample on the fluorescence image;

[0018] For each pixel position on the fluorescence image, the energy of the pixel position is determined based on the pixel position and the Bragg angle corresponding to the characteristic peak of the standard sample.

[0019] The spectrometer device of the present application adopts multiple crystals to collect fluorescence of the sample, has a larger solid angle and higher collection efficiency; the third displacement table only needs to adjust the crystals through two dimensions to realize focusing of the light spot, has a simpler structure and lower cost. BRIEF DESCRIPTION OF DRAWINGS

[0020] Figure 1 It is a structural schematic diagram of one view of the spectrometer device according to an embodiment of the present application;

[0021] Figure 2 It is a structural schematic diagram of another view of the spectrometer device according to an embodiment of the present application;

[0022] Figure 3 It is a physical model schematic diagram of a von Hamos spectrometer;

[0023] Figure 4 It is an image of Fe2O3 Kb emission spectrum on a position sensitive detector, in which the left side is obtained by focusing of diffraction of two crystals, and the right side is obtained by focusing of diffraction of four crystals;

[0024] Figure 5A It is a Si(444) crystal elastic scattering peak and a fitting curve when the Bragg angle is 80.7° at 8017.5 eV;

[0025] Figure 5B It is an elastic scattering peak of a Si(444) crystal in the range of 8017-8120 eV;

[0026] Figure 5C It is a Cu Ka XES spectrum collected at different incident X-ray dose levels;

[0027] Figure 6A It is a Kb-RIXS spectrum of LMCN;

[0028] Figure 6B It is a comparison of a Mn HERFD-XANES spectrum and a conventional XANES spectrum of LMCN;

[0029] Figure 7 It is a Kb emission spectrum of Fe foil and Fe2O3 collected based on five Si(531) crystals;

[0030] Figure 8 It is a Cu Kα spectrum line diagram with a collection time of 0.2 seconds. DETAILED DESCRIPTION

[0031] The preferred embodiments of the present application are described below in detail with reference to the accompanying drawings.

[0032] As shown in Figure 1 and Figure 2 , the embodiment of the present application provides a spectrometer device, which comprises a first displacement table 100, a second displacement table 200, a sample table 300 and a position sensitive detector 400, the position sensitive detector 400 is arranged on the first displacement table 100, the first displacement table 100 is used to move the position sensitive detector 400 along the X, Y and Z directions, so as to adjust the X, Y and Z positions of the position sensitive detector 400; the second displacement table 200 is provided with a plurality of third displacement tables 500, the second displacement table 200 is used to move each third displacement table 500 along the Z direction; each third displacement table 500 is provided with a crystal 600, and each third displacement table 500 is used to move the crystal 600 thereon along the X direction and rotate the crystal 600 thereon around the Z axis; the sample table 300 is provided with a sample holder 700, and the sample holder 700 is used to fix a sample; the position sensitive detector 400 is located above the sample holder 700, each crystal 600 is arranged around the sample holder 700, each crystal 600 is a cylindrical bent crystal (the generatrix of the cylindrical bent crystal extends along the Z direction), each crystal 600 is arranged in a circular arc along a circle in a circumferential direction and forms a spliced crystal, and the spliced crystal is equivalent to a larger cylindrical bent crystal. The sample is used to be irradiated by incident X rays, after the incident X rays irradiate on the sample, the measured element core level electrons in the sample are excited and fluorescent light (i.e. characteristic X rays) is emitted, the fluorescent light is transmitted to each crystal 600 and Bragg diffraction occurs on each crystal 600, and the position sensitive detector 400 is used to receive the diffraction light of each crystal 600 to obtain a spot image of the diffraction light of each crystal 600.

[0033] The principle of the spectrometer device of the embodiment of the present application is based on the principle of the wavelength dispersion von Hamos spectrometer of the cylindrical bent crystal, and the physical model of the von Hamos spectrometer is shown in Figure 3 , the sample 10 and the detector 20 are arranged on the central axis of the cylindrical bent crystal 30, after the incident X rays irradiate on the sample, the fluorescent light is generated, the included angle between the sample point and the generatrix direction of the cylindrical bent crystal 30 is the Bragg angle, different positions of the cylindrical bent crystal 30 correspond to different Bragg angles, that is, each position of the cylindrical bent crystal 30 in the generatrix direction can diffract the X rays of the corresponding energy and transmit them to different positions of the detector 20, so as to realize the wavelength dispersion spectroscopy of the fluorescent spectral line. The circumferential direction of each position of the generatrix can focus the fluorescent spectral line of the same energy, so as to improve the signal collection efficiency of the spectrometer.

[0034] In order to reduce elastic scattering and improve signal-to-noise ratio, the sample is set at 45° to the incident X-ray, and the distribution of the components of the von Hamos spectrometer is determined by the Bragg angle corresponding to the energy of the characteristic spectral line of the target:

[0035] (1)

[0036] wherein, X C is the distance from the sample point to the midpoint on the central axis of the cylindrical bent crystal 30, R is the radius of curvature of the cylindrical bent crystal 30, q is the Bragg angle corresponding to the energy of the X-ray fluorescence of the target, and correspondingly, the position of the sample 10 to the recording point of the target spectral line on the detector X D =2 X C Based on formula (1), assuming that a cylindrical bent crystal with a Si(444) crystal surface is used, with a radius of curvature of 250 mm, for collecting a Cu Kα1 fluorescence spectral line with an energy of 8046 eV, the corresponding Bragg angle is 79.57°, the distance from the sample 10 to the midpoint on the central axis of the cylindrical bent crystal 30 is 47.2 mm, and the corresponding distance from the sample 10 to the detector 20 is 94.4 mm. If the von Hamos spectrometer is applied to wavelength dispersion of X-rays, the dispersion at each energy point can be derived from the following formula:

[0037] (2)

[0038] wherein x is the distance of the distribution of the X-ray at a certain energy on the detector 20. For an X-ray fluorescence spectral line with an energy of 8046 eV and a detector with a pixel size of 172 um in the dispersion direction, the theoretical dispersion capability is 0.5 eV / pixel.

[0039] A great advantage of the von Hamos configuration spectrometer is that it can cover a wide range of fluorescence spectral line energy, and the available range of capabilities covered is determined by the length of the crystal and the relative positions of the components of the spectrometer:

[0040] (3)

[0041] , (4)

[0042] wherein, E Range is the energy range covered by the spectrometer, q is the Bragg angle corresponding to the energy of the X-ray fluorescence of the target, L is the length of the cylindrical bent crystal, Ris the Bragg angle corresponding to the minimum energy covered by the spectrometer, q 1 is the Bragg angle corresponding to the minimum energy covered by the spectrometer, q 2 is the Bragg angle corresponding to the minimum energy covered by the spectrometer. Similarly, for the X-ray fluorescence spectrum line with the central energy of 8046 eV, assuming the length of the cylindrical bent crystal is 100 mm, the energy range covered by the cylindrical bent crystal is 577 eV (7910-8487 eV), which is enough to detect characteristic spectrum lines even fluorescence spectrum lines of different elements.

[0043] The bending direction of the cylindrical bent crystal can focus the fluorescence spectrum lines with the same energy. Compared with the planar crystal, the cylindrical bent crystal has a larger collection angle, effectively increasing the signal collection efficiency, and is related to the width of the focusing direction of the cylindrical bent crystal and the relative position of the spectrometer components determined by the characteristic spectrum line energy. According to the formula derived by Uwe Bergmann et al., the solid angle of the von Hamos spectrometer is proportional to the sine value of the Bragg angle, and the collection efficiency can be calculated by the following formula:

[0044] (5)

[0045] wherein n is the aperture opening angle of the cylindrical bent crystal, s is the vertical size of the incident X-ray spot. The meaning of formula (5) is the collection efficiency ratio of the cylindrical bent crystal and the planar crystal. For the bent crystal with the aperture opening angle of 0.2 rad, when the spot size of the incident X-ray is 100 mm x 200 mm (vertical x horizontal), the collection efficiency ratio of the fluorescence spectrum line with the energy of 8046 eV is about 500, which proves the high collection efficiency of the von Hamos spectrometer.

[0046] Each crystal 600 of the spectrometer device of the embodiment of the present application corresponds to the cylindrical crystal in the von Hamos spectrometer, the more the number of the crystals 600, the larger the solid angle, and the higher the collection efficiency, but too many crystals 600 may interfere with the incident X-ray, so various factors need to be considered comprehensively to obtain the optimal number of the crystals 600.

[0047] The Bragg angle of each crystal 600 at different positions can be adjusted by adjusting the Z-direction position of the position sensitive detector 400 through the first displacement table 100 and / or adjusting the Z-direction position of each crystal 600 through the second displacement table 200, so as to collect fluorescent spectral lines of different energies. The sample can be located on the central axis of the mosaic crystal (also the central axis of the crystal 600) by adjusting the X-direction position of each crystal 600 through the third displacement table 500, and the position sensitive detector 400 can be located directly above the sample by adjusting the X-direction and Y-direction positions of the position sensitive detector 400 through the first displacement table 100, so that the position sensitive detector 400 can also be located on the central axis; when the sample and the position sensitive detector 400 are located on the central axis of each crystal 600, the light spots formed by each crystal 600 on the position sensitive detector 400 will be focused to the smallest. The position of the light spot in the transverse direction can be adjusted by rotating the crystal 600 around the Z-axis through the third displacement table 500.

[0048] After the Z-direction positions of the position sensitive detector 400 and each crystal 600 are fixed, the Bragg angle of each crystal 600 at different positions is also fixed. Then, each crystal 600 can be moved along the X-direction and rotated around the Z-axis through the third displacement table 500, so as to focus the light spots formed by the diffraction light of each crystal 600 on the position sensitive detector 400 at the same point or focus the light spots formed by the diffraction light of each crystal 600 on the position sensitive detector 400 at different points in the best state (the light spot is the brightest and smallest). If the light spots of the diffraction light of each crystal 600 are focused at the same point, data collection and processing can be directly performed, and the collection efficiency can be improved.

[0049] The first displacement table 100 can include a first X-direction moving table, a first Y-direction moving table and a first Z-direction moving table, the first Y-direction moving table is arranged on the first X-direction moving table, the first Z-direction moving table is arranged on the first Y-direction moving table, and the position sensitive detector 400 is arranged on the first Z-direction moving table. The first X-direction moving table is used to move the first Y-direction moving table arranged thereon along the X-direction, the first Y-direction moving table is used to move the first Z-direction moving table arranged thereon along the Y-direction, and the first Z-direction moving table is used to move the position sensitive detector 400 arranged thereon along the Z-direction. In this way, the X-direction movement of the position sensitive detector 400 can be realized through the first X-direction moving table, the Y-direction movement of the position sensitive detector 400 can be realized through the first Y-direction moving table, and the Z-direction movement of the position sensitive detector 400 can be realized through the first Z-direction moving table.

[0050] Each third displacement stage 500 can include a second X-direction displacement stage and a Z-direction rotation stage, the Z-direction rotation stage is arranged on the second X-direction displacement stage, and the crystal 600 is arranged on the Z-direction rotation stage. The second X-direction displacement stage is used to move the Z-direction rotation stage on which the crystal 600 is arranged along the X direction, and the Z-direction rotation stage is used to rotate the crystal 600 around the Z axis. In this way, the third displacement stage 500 can move the crystal 600 along the X direction through the second X-direction displacement stage and rotate the crystal 600 around the Z axis through the Z-direction rotation stage.

[0051] The second displacement stage 200 can be provided with an arc-shaped support 800, and each third displacement stage 500 can be arranged on the arc-shaped support 800 in sequence. Each crystal 600 can be fixed on the third displacement stage 500 through a crystal support.

[0052] For example, the position-sensitive detector 400 can be a Pilatus 100K-M face detector, and the pixel size is 172mm´172mm. The radius of curvature of each crystal 600 is 250mm, and the radius of curvature of the spliced crystal is also 250mm. The crystal face size of the crystal 600 is 100mm´25mm (focusing´dispersion). The number of crystals 600 is five, that is, the spectrometer device includes five crystals 600, and the normal line of the middle crystal 600 is perpendicular to the direction of incident X-rays.

[0053] The crystal 600 can be replaced with different crystals as needed to test different elements. For example, a Si (531) crystal is needed when testing Fe, and a Si (444) crystal is needed when testing Cu. When replacing the crystal, the original crystal needs to be removed from the third displacement stage 500 first, and then the new crystal is installed on the third displacement stage 500. Then, the Z-direction position of the position-sensitive detector 400 is adjusted through the first displacement stage 100, and the Z-direction position of each crystal 600 is adjusted through the second displacement stage 200, so that the Bragg angle of the crystal 600 corresponds to the Bragg angle of the spectrum line of the element to be tested. Since the installation tolerance of the crystal 600, the radius of curvature error of the crystal itself, the thickness error of the crystal and the like will affect the shape and position of the focused light spot, it is also necessary to adjust the X-direction position and the angle around the Z axis of each crystal 600 through the third displacement stage 500 to optimize the light spot (so that the light spots of each crystal 600 are focused together or focused at different positions but in the best state).

[0054] As Figure 4As shown, in a single acquisition, different crystals 600 diffract fluorescence into similar spot shapes. Differences in crystal orientation and surface shape errors can cause subtle changes in the spot image on the detector. By finely adjusting the crystal orientation, the spots of multiple crystals 600 can be focused onto the same point of the position-sensitive detector 400. The resulting focused spot image can be aligned with the position of a single spot generated by each crystal 600, demonstrating the effectiveness of the crystal motion control mechanism of the spectrometer device of this invention.

[0055] To evaluate the energy resolution of the spectrometer, elastic scattering peaks were collected. For example... Figure 5A As shown, at 8017.5 eV (Bragg angle of 80.7°), using five Si(444) crystals, an energy resolution of 1.2 eV was obtained by measuring the half-width at half-maximum (FWHM). To further clarify the stability of the energy resolution of the spectrometer at different Bragg angles, the elastic scattering peaks in the Bragg angle range of 80.7° to 77.7° were detected, and their FWHM gradually increased from 1.2 eV at 80.7° to 1.6 eV at 77.7° (e.g., ...). Figure 5B (As shown). It is worth noting that, under the same conditions, the increase in FWHM with decreasing Bragg angle in the spectrometer device of this embodiment is smaller than that in the spherical curved crystal spectrometer. This enhanced performance can be attributed to the compact structure of the spectrometer device, which is beneficial for detecting spectral lines at low Bragg angles while maintaining high energy resolution.

[0056] To further illustrate the time-resolution advantage of the spectrometer, XES spectral lines at integration times of different detectors were systematically probed, thus simulating different incident photon fluxes. For example... Figure 5C As shown, Cu Ka spectral lines excited by different photon counts exhibit different signal-to-noise ratios. At a photon count of 9 × 10⁻⁶, the signal-to-noise ratio is significantly higher. 7 At phs / s, the spectrum exhibits negligible noise. This indicates that the spectrometer can achieve time resolution on the order of seconds or even milliseconds when probed by high-throughput radiation sources such as diffraction-limited storage rings or free-electron lasers.

[0057] To verify the performance of the spectrometer in practical applications, a series of RIXS, HERFD-XANES, and XES detections were performed. In the RIXS detection, Li₂, a commercially available lithium-ion battery cathode material, was used. 1.2 Ni 0.13 Co 0.13 Mn 0.54 Using O2 (LMCN) as a sample, the Kb-RIXS spectrum of Mn was tested, as follows: Figure 6AAs shown. The test procedure involves irradiating the LMCN with incident X-rays of different energies, then acquiring a spectrum at each incident energy, and combining the XES spectral lines from all incident energies to obtain the RIXS spectrum. Profile curves are obtained by setting a fixed emission energy, such as a fixed Kb. 1,3 By profiling the peaks along the incident energy, high-resolution absorption spectra (HERFD-XANES) can be obtained, such as... Figure 6B As shown. Figure 6B In the image, the red line represents the Mn HERFD-XANES spectrum of LMCN, and the blue line represents the conventional XANES spectrum. It can be seen that HERFD-XANES has a narrower broadening and higher intensity in important features such as the front peak and shoulder peak.

[0058] In addition, Kb XES lines of Fe foil and Fe2O3 were detected, especially VtC-XES lines (such as...). Figure 7 As shown in the figure, this further demonstrates the ability of this spectrometer to operate on low transition probability spectra.

[0059] There are two methods for calibrating X-ray fluorescence images obtained by position-sensitive detectors in spectrometers:

[0060] (1) Detect the characteristic spectral lines of the corresponding element standard sample, such as the Ka1 spectral line of Cu foil. Since its theoretical fluorescence energy is clear, the energy value corresponding to each position on the PSD can be determined. Figure 8 The lower middle section shows the Cu foil Kα spectral fluorescence spot image obtained directly from the position-sensitive detector. The larger spot intensity is the Kα1 spectral line, and the smaller one is the Kα2 spectral line. Figure 8 The intensity of the upper peak is obtained by integrating directly from the white dashed line in the light spot image. The ratio of the two peaks is close to 2:1, which corresponds to the transition probability of the Kα spectral line of the Cu foil. Assuming the Bragg angle corresponding to the fluorescence energy of the Kα1 spectral line of the Cu foil is... q 0 The energy corresponding to each pixel on the position-sensitive detector can be calculated:

[0061] (6)

[0062] Where n is the position of a location in the position-sensitive detector and the Bragg angle. q 0 The number of pixels that correspond to the positions. p Let be the PSD pixel size in the dispersion direction, h be Planck's constant, c be the speed of light, and d be the interplanar spacing. Based on the above formula, the energy values ​​at various positions on the PSD were calculated using the fluorescence energy of the Kα1 spectral line on the Cu foil. Theoretically, the pixel difference between the Kα1 and Kα2 spectral line fluorescence spots should be 42, but the actual measured pixel difference is 41, with an error of 2.38%.

[0063] (2) Calibration by elastic scattering peak. The characteristic of elastic scattering is that the energy of incident X-ray is the same as that of emitted X-ray fluorescence. Therefore, when detecting the Kα spectrum of a Cu sample, the energy of incident X-ray is set to be the energy of the Kα1 spectrum of a Cu foil, and then a light spot of elastic dispersion peak with the same energy can be obtained after a long exposure. According to formula (6), the energy value of each pixel point on the PSD can be obtained. The advantage of calibration by elastic scattering peak is that it does not need to replace the standard sample, thereby ensuring the stability of the structure in detection. Especially for in-situ emission spectrum detection, since the size of the in-situ cell does not match the size of the conventional sample holder, the calibration by elastic scattering peak can avoid the error caused by the fine adjustment of the sample point.

[0064] The spectrometer device of the embodiment of the present application adopts multiple crystals 600 to collect the fluorescence of the sample, has a larger solid angle and higher collection efficiency; the third displacement table 500 only needs to adjust the crystals 600 through two adjustment dimensions to realize the focusing of the light spot, has a simpler structure and lower cost.

[0065] The above is only a preferred embodiment of the present application, and is not intended to limit the scope of the present application. The above embodiment of the present application can also be variously changed. Any simple, equivalent change and modification made according to the content of the claims and the specification of the present application application falls within the protection scope of the present application. The present application is not described in detail, and all conventional technical contents are included.

Claims

1. A spectrometer device, characterized in that, The device includes a first displacement stage, a second displacement stage, a sample stage, and a position-sensitive detector. The position-sensitive detector is disposed on the first displacement stage, which is used to move the position-sensitive detector along the X, Y, and Z axes. The second displacement stage has multiple third displacement stages, which are used to move each third displacement stage along the Z axis. Each third displacement stage has a crystal, which is used to move the crystal along the X axis and rotate it about the Z axis. The sample stage has a sample holder for fixing the sample. The position-sensitive detector is located above the sample holder, and the crystals are arranged around the sample holder. Each crystal is a cylindrical bent crystal. The sample is used to receive incident X-rays and generate fluorescence under the irradiation of the incident X-rays. The fluorescence is transmitted to each crystal, where Bragg diffraction occurs. The position-sensitive detector receives the diffracted light from each crystal to obtain a fluorescence image, which contains spots formed by the diffracted light from each crystal.

2. The spectrometer apparatus according to claim 1, characterized in that, The crystals are arranged sequentially along the circumference of a circular arc.

3. The spectrometer apparatus according to claim 1, characterized in that, Different positions of each crystal correspond to different Bragg angles, and the Bragg angles of different positions of each crystal are set to change as the position-sensitive detector moves along the Z-direction and / or each crystal moves along the Z-direction.

4. The spectrometer apparatus according to claim 1, characterized in that, The size and brightness of the spot formed by the diffracted light of each crystal on the position-sensitive detector change as the crystal moves along the X-axis, and the lateral position of the spot formed by the diffracted light of each crystal on the position-sensitive detector changes as the crystal rotates around the Z-axis.

5. The spectrometer apparatus according to claim 4, characterized in that, The diffracted light from each crystal forms a spot on the position-sensitive detector that is located at the same position or at different positions but in an optimal state.

6. The spectrometer apparatus according to claim 1, characterized in that, The first displacement stage includes a first X-axis moving stage, a first Y-axis moving stage, and a first Z-axis moving stage. The first Y-axis moving stage is disposed on the first X-axis moving stage, the first Z-axis moving stage is disposed on the first Y-axis moving stage, and the position sensitive detector is disposed on the first Z-axis moving stage. The first X-axis moving stage is used to move the first Y-axis moving stage along the X-axis, the first Y-axis moving stage is used to move the first Z-axis moving stage along the Y-axis, and the first Z-axis moving stage is used to move the position sensitive detector along the Z-axis.

7. The spectrometer apparatus according to claim 1, characterized in that, Each of the third displacement stages includes a second X-axis moving stage and a Z-axis rotating stage. The Z-axis rotating stage is disposed on the second X-axis moving stage, and the crystal is disposed on the Z-axis rotating stage. The second X-axis moving stage is used to move the Z-axis rotating stage along the X-axis, and the Z-axis rotating stage is used to rotate the crystal about the Z-axis.

8. The spectrometer apparatus according to claim 1, characterized in that, The second displacement stage is provided with an arc-shaped support, and each third displacement stage is sequentially arranged on the arc-shaped support; each crystal is fixed on the third displacement stage by a crystal support.

9. The spectrometer apparatus according to claim 1, characterized in that, There are five crystals, each with a radius of curvature of 250 mm and a crystal face size of 100 mm × 25 mm.

10. The spectrometer apparatus according to claim 1, characterized in that, The calibration method for the fluorescence image includes: The characteristic spectral lines of the standard sample are detected to obtain fluorescence images of the characteristic spectral lines of the standard sample. Obtain the pixel positions of the characteristic peaks of the standard sample in the fluorescence image; For each pixel location in the fluorescence image, the energy at that pixel location is determined based on the pixel location of the characteristic peak of the standard sample and the Bragg angle corresponding to the characteristic peak of the standard sample.

Images