Spectrometer

Abstract

The invention relates to a spectrometer comprising a crystal analyzer operably connected to a first arm, a detector operably connected to a second arm, a third arm operably connected to the second arm, a fourth arm operably connected to the third arm, a first motor operably connected to the first arm, and a second motor operably connected to the second arm. And a second motor operably connected to the fourth arm. The first arm is connected to the second arm at a first axis. A first motor is configured to rotate the first arm to position the crystal analyzer, and a second motor is configured to rotate the fourth arm to position the probe through the third arm and the second arm. The first motor and the second motor operate independently of each other. Moving the probe by the second motor, the fourth arm, the third arm, and the second arm, and moving the crystal analyzer by the first motor and the first arm can allow the probe and the crystal analyzer to rotate independently of each other about the first axis.

Description

[0001] This application is a divisional application of Chinese patent application No. 202080073140.5, filed on October 21, 2020, entitled "Spectrometer". Technical Field

[0002] This invention relates to a spectrometer. Background Technology

[0003] A spectrometer (“spectrometer”) is used to separate target X-rays for quantitative analysis. The general process of wavelength dispersive fluorescence spectroscopy involves first stimulating specific elements to produce X-ray signatures using X-rays incident from a radiation source (such as an X-ray tube or synchrotron radiation beam) or incident particle radiation (such as electron, proton, or ion beams). Once X-rays are generated in the sample, a crystal analyzer with a defined lattice spacing can be used to select the X-rays. When the X-rays generated by the sample encounter the crystal analyzer at a specific angle, only X-rays with wavelengths that satisfy Bragg's law will diffract. By controlling the sample position and the size of the sample's emitting region, X-rays of different energy bands emitted from different regions of the sample interact with the crystal analyzer and diffract. In Rowland circle geometry, diffraction occurs as follows: when X-rays are refocused on the Rowland circle, they are spatially ordered according to their respective energies. Using a position-sensitive X-ray detector (“detector”), placed on the Rowland circle, these refocused rays are measured using the relationship between the refocusing position and energy, and the X-rays measured on the detector are assigned to specific energies. Alternatively, when the spectrometer is used with a single-channel detector (position insensitive), the spectrometer can be operated in a point-to-point focusing mode, and the detector can be used to measure the single X-ray energy at each point.

[0004] In Rowland circle geometry, the position of the crystal analyzer defines the Rowland circle, and ideally, the detector must be tangent to the Rowland circle. Once the Rowland circle is defined, the sample and detector must be placed symmetrically relative to the crystal analyzer so that the X-rays being analyzed diffract towards the detector. Typically, since the position of the excitation X-ray or incident beam is fixed, the sample is stationary. Therefore, as the angles of the crystal and detector change, the measured Bragg angle and energy region of the X-rays generated by the sample or radiation source change. The crystal analyzer and detector must move simultaneously to maintain the Rowland geometry.

[0005] Therefore, in order to analyze the fluorescence lines of various elements in a sample using a spectrometer, it is necessary to continuously reorient the crystal analyzer and detector. A spectrometer capable of precisely positioning these components and reorienting them as needed is required. The reorientation device can also reorient the spectrometer in an environment such as a vacuum or inert gas glove box or chamber without disturbing the environment. In one embodiment, the inert gas glove box or chamber is filled with helium. In another embodiment, the spectrometer is installed in a vacuum chamber or a helium-filled chamber; this spectrometer has two main uses. First, it can be used to measure the energy spectrum of X-ray photons emitted by the sample. When measured at very high energy resolution, this X-ray fluorescence spectrum is called X-ray emission spectroscopy (XES). This measurement can be performed because X-rays are incident on the sample, or if electrons or other charged particles are incident on the sample (e.g., in an electron microscope or proton-induced XES system). Second, an X-ray tube or X-ray source can be aligned with the spectrometer entrance so that the energy spectrum of photons emitted by the X-ray source itself is formed on the detector. In this case, the sample is inserted between the radiation source and the analyzer or between the analyzer and the detector. The changes in spectral intensity caused by the insertion of the sample can then be analyzed to determine the X-ray absorption fine structure (XAFS) of the sample. This invention proposes a spectrometer with a platform for manipulating and orienting the crystal analyzer and detector. Summary of the Invention

[0006] This invention relates to a spectrometer comprising a crystal analyzer operably connected to a first arm, a detector operably connected to a second arm, a third arm operably connected to the second arm, a fourth arm operably connected to the third arm, a first motor operably connected to the first arm, and a second motor operably connected to the fourth arm. The first arm and the second arm are connected at a first axis. The first motor is configured to rotate the first arm to position the crystal analyzer, and the second motor is configured to rotate the fourth arm to position the detector via the third and second arms. The first motor and the second motor operate independently of each other. Movement of the detector via the second motor, the fourth arm, the third arm, and the second arm, and movement of the crystal analyzer via the first motor and the first arm, allows the detector and the crystal analyzer to rotate independently of each other about a first axis. Attached Figure Description

[0007] Other features and advantages of the present invention will be clearly described in the following specific embodiments with reference to the accompanying drawings. (To be determined when the drawings are finalized.)

[0008] Figure 1 This is a side view of the spectrometer.

[0009] Figure 2a This is a top view of the spectrometer.

[0010] Figure 2b This is a perspective view of one embodiment of the spectrometer.

[0011] Figure 2c This is a side view of one embodiment of the spectrometer.

[0012] Figure 3 This is a side view of one embodiment of the spectrometer.

[0013] Figure 4a This is a side view of one embodiment of the spectrometer.

[0014] Figure 4b This is a side view of one embodiment of the spectrometer.

[0015] Figure 5 This is a side view of one embodiment of the spectrometer.

[0016] Figure 6 An environmental diagram of one embodiment of the spectrometer.

[0017] Figure 7a An example of an X-ray characteristic spectrum obtained using the spectrometer is shown.

[0018] Figure 7b Another example of an X-ray characteristic spectrum obtained using the spectrometer is shown.

[0019] Figure 7c Another example of an X-ray characteristic spectrum obtained using the spectrometer is shown.

[0020] Figure 8a An exemplary embodiment of the spectrometer for displaying an 80° Bragg angle.

[0021] Figure 8b An exemplary embodiment of the spectrometer displaying a 70° Bragg angle.

[0022] Figure 8c An exemplary embodiment of the spectrometer for displaying a 60° Bragg angle.

[0023] Figure 8d An exemplary embodiment of the spectrometer displaying a 50° Bragg angle. Detailed Implementation

[0024] In the following detailed description, reference is made to the accompanying drawings, which form a part of the description. In the drawings, unless the context otherwise requires, similar or identical symbols are generally used in different drawings to denote similar or identical items.

[0025] The exemplary embodiments described in the detailed description, drawings, and claims are not intended to limit the invention. Other embodiments and modifications may be made without departing from the spirit and scope of the invention.

[0026] Those skilled in the art will recognize that, for clarity of concept, the components (e.g., operations), devices, objects, and related discussions described in this invention are merely illustrative and take into account various configuration modifications. Therefore, the specific examples and related discussions used in this invention are intended to represent more general categories. In general, the use of any specific example is intended to represent the category to which it belongs, and the omission of specific components (e.g., operations), devices, and objects should not be considered a limitation of the invention.

[0027] For clarity of demonstration, formal outline headings are used in this application. However, it should be understood that outline headings are intended for illustrative purposes, and different types of topics may be discussed throughout the application (e.g., equipment / structures may be described under process / operation headings, and / or process / operational aspects may be discussed under structure / process headings; and / or the description of a single topic may span two or more topic headings). Therefore, the use of formal outline headings is not intended to limit the invention in any way.

[0028] refer to Figure 1 According to one embodiment, the spectrometer (100) includes a detector (40) and a crystal analyzer (30) rotatably positioned about a first axis; in some embodiments, the axis is centered on a Rowland circle (60) of radius r. Generally, the detector (40) and the crystal analyzer (30) can be positioned independently of each other along the Rowland circle (60), such that the radiation source (51) is located in the region where the crystal analyzer (30) receives Bragg diffraction.

[0029] The crystal analyzer (30) is operatively connected to a first arm (la), the position of which is controlled by a first motor (20a). The first arm (la) consists of a distal end (21b) and a proximal end (21a). In one embodiment, the first motor (20a) is operatively connected to the distal end (21b) of the first arm (la). The crystal analyzer (30) is operatively connected to the distal end (21b) of the first arm (la). In one embodiment, the crystal analyzer (30) is mounted to the distal end (21b) using any known mounting method. The first motor (20a) moves the first arm (la), which moves the center of the Rowland circle while the crystal analyzer (30) remains tangent. In one embodiment, the crystal analyzer (30) is mounted in a manner that allows it to rotate relative to its mounting point. In one embodiment, the crystal analyzer is mounted in a manner that allows its radial position r to be adjusted, moving the crystal analyzer closer to or further away from the first axis. In one embodiment, the crystal analyzer (30) is a Johann-type crystal analyzer, wherein the crystal surface is curved along a circle twice the size of a Rowland circle. In another embodiment, the crystal analyzer (30) is a Johansson-type crystal analyzer, wherein the lattice plane is curved to twice the radius of a Rowland circle, and the crystal surface is ground / manufactured to have the same radius as a Rowland circle. In yet another embodiment, a diffraction grating is used instead of a crystal analyzer.

[0030] A first arm (la) is operatively connected to a second arm (lb). The second arm (lb) has a proximal end (22a) and a distal end (22b). The proximal end (21a) of the first arm (la) is operatively connected to the proximal end (22a) of the second arm (lb). The distal end (22b) of the second arm (lb) is operatively connected to a detector (40). In one embodiment, the detector (40) is mounted to the second arm using any known mounting method. In one embodiment, the detector (40) is mounted on the second arm (lb) such that the detection surface is perpendicular to the second arm (lb). In one embodiment, the detector is mounted in a manner that adjusts its radial position r.

[0031] The second arm (lb) is connected to the third arm (lc). The third arm (lc) has a proximal end (23a) and a distal end (23b). The distal end (22b) of the second arm (lb) is operatively connected to the proximal end (23a) of the third arm (lc). In one embodiment, the second arm (lb) and the third arm (lc) are operatively connected such that the detector (40) can move tangentially along the circle.

[0032] The third arm (lc) is connected to the fourth arm (1d). The fourth arm has a proximal end (24a) and a distal end (24b). The distal end (23b) of the third arm (lc) is operatively connected to the proximal end (24a) of the fourth arm (1d). The distal end (24b) of the fourth arm (ld) is operatively connected to a second motor (20b). In one embodiment, the second motor (20b) is mounted to the fourth arm (1d) using any known mounting method. The second motor (20b) enables the fourth arm (1d) to rotate.

[0033] In one embodiment, the first motor (20a) and the second motor (20b) are controlled by a computing device (not shown). Figures 8a-8d Exemplary embodiments of several spectrometers at the Bragg angle are shown.

[0034] refer to Figure 1 , 2a In one embodiment, the crystal analyzer (30) can receive X-rays emitted by or through the sample (51). In one embodiment, the crystal analyzer (30) operates by selectively scattering radiation within a specific wavelength / band using Bragg diffraction, depending on the lattice spacing of the crystal analyzer (30) and its orientation relative to the sample (51). In another embodiment, the crystal analyzer (30) operates by selectively scattering radiation within a specific wavelength / band using Bragg diffraction, depending on the lattice spacing of the crystal analyzer (30) and its orientation relative to the radiation source (50). In one embodiment, the crystal analyzer (30) is cylindrical. In one embodiment, the crystal analyzer (30) is toroidal. In one embodiment, the crystal analyzer (30) is spherical. In one embodiment, the crystal analyzer (30) has a focusing ring with a diameter of approximately 10-20 cm. In another embodiment, the crystal analyzer (30) has a focusing circle with a diameter of approximately 20-100 cm. In one embodiment, the detector (40) can detect the count, intensity, and / or energy / wavelength of the X-rays diffracted by the crystal analyzer (30). Those skilled in the art will recognize that, depending on the configuration, the detector (40) may be a position-sensitive detector or a single-channel detector. Those skilled in the art will recognize that the crystal analyzer (30) and the detector (40) may each comprise various materials to achieve the desired configuration.

[0035] refer to Figure 1 , 2aIn one embodiment, the first arm (la) and the second arm (lb) allow the crystal analyzer (30) and detector (40) to remain tangent to the Rowland circle (60). In one embodiment, a first motor (20a) rotates the first arm (la), a second motor (20b) rotates the arm (1d), and subsequently rotates the other linked arms (lb, lc), allowing the angle A between the detector (40) and the crystal analyzer (30) to change. In one embodiment, the first motor (20a) rotates the first arm (la), the second motor (20b) rotates the arm (1d), and subsequently rotates the other linked arms (lb, lc), so that when the sample (51) remains stationary, the angle A between the detector (40) and the crystal analyzer (30) and the angle B between the crystal analyzer (30) and the sample (51) remain equal. In one embodiment, the first motor (20a) or the second motor (20b) can be operated independently to adjust the position of the crystal analyzer (30) and the detector (40). By adjusting this angle, X-rays generated by radiation sources or samples (51) of different wavelengths can satisfy Bragg's law and can be measured by a detector (40).

[0036] refer to Figure 3 In one embodiment, the spectrometer (100) is operably mounted on a linear translation stage (70). The linear translation stage (70) moves the motorized spectrometer (100) from at least a first position X1 to a second position X2, changing the distance between the sample (51) and the crystal analyzer (30) while keeping the sample-crystal-detector angle constant. (See reference...) Figure 6 In one embodiment, the spectrometer (100) is housed in an inert gas glove box (200). In another embodiment, the spectrometer (100) is housed in a vacuum chamber or a helium-filled chamber. In one embodiment, the spectrometer (100) is oriented such that the Rowland circle is in a vertical plane. In another embodiment, the spectrometer (100) is oriented such that the Rowland circle is in a horizontal plane.

[0037] Referring to Figure 4, in one embodiment, the radiation source (50) may be an X-ray tube, a synchrotron, a laser plasma X-ray source, a scanning electron microscope, a proton beam, or an ion beam. The radiation source (50) may emit X-rays toward the sample (51), and the radiation source (50) may cause the sample (51) to emit radiation toward the crystal analyzer (30). In this embodiment, the detector (40) may measure the X-ray emission spectrum of the sample (51). The sample (51) used herein may be of any material. Those skilled in the art will recognize that when referring to the sample (51), it should be understood that the sample (51) is operatively connected to the radiation source, whether or not the radiation source is explicitly mentioned.

[0038] refer to Figure 5In one embodiment, the radiation source (50) is an X-ray tube. In one embodiment, the radiation source (50) may emit X-rays toward a crystal analyzer (30), and a sample (51) may be placed between the radiation source (50) and the crystal analyzer (30), or between the crystal analyzer (30) and the detector (40). By comparing the signals on the detector (40) (with and without the sample (51)), the fine structure of X-ray absorption of the sample (51) can be determined. In other embodiments, the radiation source (50) may be a synchrotron or a laser plasma X-ray source.

[0039] In one embodiment, a spectrometer is used to study actinides. In one embodiment, a spectrometer is used to study gas-sensitive electrode materials required for electrical energy storage. In one embodiment, a spectrometer is used to study gas-sensitive materials required for chemical catalysis.

[0040] In one embodiment, the computing device is programmed to control motors (20a, 20b), which in turn control arms (1a, 1b, 1c, 1d), thereby achieving multiple angles between the crystal analyzer (30) and the sample (51) or radiation source (50). In one embodiment, the computing device is pre-programmed to control motors (20a, 20b) to orient the crystal analyzer (30) and detector (40) to predetermined positions, such as specific energies of element emission lines. In one embodiment, a second motor (1b) rotates a fourth arm (1d), thus rotating other linked arms (1c, 1b, 1a), thereby moving the detector (40), while the crystal analyzer (30) remains stationary.

[0041] Using a spectrometer (100), and by electrodynamic tuning to different energy ranges (i.e., emission lines), the following results were obtained. Figure 7a and 7b High-resolution spectra are obtained in this study. In one exemplary embodiment, the sample is a phosphorus- or sulfur-containing compound. For phosphorus and sulfur, the Kα spectrum consists of two closely spaced peaks. For the phosphorus compound, the energy separation is -0.85 eV, and for the sulfur compound, it is -1.24 eV. The ability to clearly resolve these two distinct peaks in the spectrum demonstrates the high energy resolution. <leV。

[0042] Figure 7a and 7b The study further revealed energy transfer between samples with very low oxidation states (e.g., ZnS, where S = -2 oxidation state) and samples with high oxidation states (e.g., CaSO4·2H2O, where S = +6 oxidation state). The energy transfer for phosphorus was -0.8 eV, and for sulfur it was -1.35 eV. This measurement was able to determine the morphology of samples in mixed oxidation states. Figure 7cThis illustrates the detection of two oxidation states, where the sample initially showing CoS indicates that some sulfur has been oxidized to SO4. 2- In one embodiment, the oxidation state distribution of phosphorus and sulfur, such as oxidation and reduction fractions, can be determined using the measurements from a spectrometer.

[0043] While various exemplary aspects and exemplary embodiments have been disclosed in this application, other aspects and embodiments will be apparent to those skilled in the art. The various exemplary aspects and exemplary embodiments disclosed in this application are intended to illustrate the invention, and not to limit it.

Claims

1. A spectrometer, comprising: A crystal analyzer, which is operatively connected to the first arm; detector, It is operably connected to the second arm; The third arm is operatively connected to the second arm; A fourth arm, which is operatively connected to the third arm; A first motor is operably connected to the first arm; as well as A second motor, which is operatively connected to the fourth arm, The first arm and the second arm are connected at the first axis; The first motor is configured to rotate the first arm to position the crystal analyzer, and the second motor is configured to rotate the fourth arm to position the detector via the third and second arms. The first motor and the second motor operate independently of each other; and The detector is moved by the second motor, the fourth arm, the third arm, and the second arm, and the crystal analyzer is moved by the first motor and the first arm, allowing the detector and the crystal analyzer to rotate independently of each other about the first axis.

2. The spectrometer according to claim 1, wherein, The first axis is centered on the Rowland circle.

3. The spectrometer according to claim 1, wherein, The first, second, third, and fourth arms are configured such that the detector and crystal analyzer remain tangent to the Rowland circle during operation.

4. The spectrometer according to claim 1, wherein: The first arm includes a proximal end and a distal end; The second arm includes a proximal end and a distal end; The third arm includes a proximal end and a distal end; The fourth arm includes a proximal end and a distal end; The proximal end of the first arm is operatively connected to the proximal end of the second arm; The distal end of the second arm is operatively connected to the proximal end of the third arm; as well as The distal end of the third arm is operatively connected to the proximal end of the fourth arm.

5. The spectrometer according to claim 4, wherein: The crystal analyzer is operatively connected to the distal end of the first arm; and The detector is operatively connected to the distal end of the second arm.

6. The spectrometer according to claim 4, wherein, The distal end of the fourth arm is operatively connected to the second motor.

7. The spectrometer according to claim 1, wherein, The first motor and the second motor are controlled by a computing device.

8. The spectrometer according to claim 7, wherein, The computing device is programmed to control the motor, and in turn control the first arm, the second arm, the third arm, and the fourth arm, so that the crystal analyzer and the sample can form multiple angles.

9. The spectrometer according to claim 7, wherein, The computing device is programmed to control the motor, and in turn control the first arm, the second arm, the third arm, and the fourth arm, so that the crystal analyzer and the radiation source can form multiple angles.

10. The spectrometer according to claim 7, wherein, The computing device is pre-programmed to control the motor, thereby positioning the crystal analyzer and detector at a defined location, such as a specific energy of an element's emission line.

11. The spectrometer according to claim 1, wherein, The first motor rotates the first arm, and the second motor rotates the second, third, and fourth arms, so that the angle between the detector and the crystal analyzer is variable.

12. The spectrometer according to claim 11, wherein, The first motor rotates the first arm, and the second motor rotates the second, third, and fourth arms, such that when the sample remains stationary, the angle between the detector and the crystal analyzer and the angle between the crystal analyzer and the sample remain equal.

13. The spectrometer according to claim 1, wherein, The fourth arm is located outside the Roland Circle during operation.

14. The spectrometer according to claim 1, wherein, The second motor rotates the second, third, and fourth arms, causing the detector to move while the crystal analyzer remains stationary.

15. The spectrometer according to claim 1, wherein, The detector is mounted on the second arm such that the detection surface is perpendicular to the second arm.

16. The spectrometer according to claim 1, wherein the third arm and the fourth arm are connected at the second axis.

17. The spectrometer according to claim 16, wherein, The second axis is located outside the Rowland circle during operation.

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