High-precision calibration device and method applied to ion fluorescence wavelength measurement

Abstract

The invention discloses a high-precision calibration device applied to ion fluorescence wavelength measurement, which is characterized in that ions are imaged to a filter slit through a lens group, and emergent light of a calibration lamp is diffused and scattered to a diffraction slit through a reflector and a diffuse scattering sheet, so that the emergent light is equivalently overlapped with an ion fluorescence emission area; the invention further discloses a high-precision calibration method applied to ion fluorescence wavelength measurement, the selection of the calibration lamp emergent spectral line is optimized by utilizing the known wavelength of inert gas ions, the calibration lamp emergent spectral line which is optimally selected is utilized to calibrate the fluorescence wavelength of ions to be measured, and the calibration is assisted by the spectral line of inert gas synchronously, so that the measurement accuracy is improved. And high-precision calibration of the fluorescence wavelength of the to-be-measured ion is realized. The method effectively solves the problem of poor measurement precision or measurement error of the to-be-measured ion spectrum caused by inaccurate or improper selection of the emergent spectral line of the calibration lamp, effectively avoids the calibration error caused by the fact that the calibration light cannot completely coincide with the fluorescence emitted by the ion, and finally greatly improves the precision and accuracy of the spectrum measurement.

Description

Technical Field

[0001] The invention belongs to the technical field of ion spectrum measurement, and in particular relates to a high-precision calibration device applied to ion fluorescence wavelength measurement, and also relates to a high-precision calibration method applied to ion fluorescence wavelength measurement. Background Art

[0002] Spectroscopic measurement is of great significance in many fields of science and technology. For example, spectral measurement provides a means to study the internal structure of matter, such as electronic energy levels, molecular vibration and rotation states, etc. Through spectral analysis, we can understand the energy structure and transition of atoms and molecules and reveal the physical properties of matter; spectral measurement is used in quantum mechanics to verify basic physical laws and quantum phenomena, such as quantum state transitions and the interaction between light and matter. Through precise spectral measurement, existing theories can be tested and the exploration of new physics can be promoted; spectral measurement can identify the composition of a substance by analyzing the light emitted or absorbed. Each element or molecule has its own unique spectral "fingerprint", and by analyzing these fingerprints, the type of element or molecule in the sample can be determined.

[0003] At present, the spectral databases of atoms, ions, etc. of various materials have been continuously improved with the development of science and technology, especially the transition wavelength data of noble gas atoms and monovalent ions have very high accuracy, generally reaching the accuracy of picometers or even femtometers. However, the spectral data of some atoms and ions are still lacking or the accuracy is too low, which is particularly reflected in the spectra of high-valent ions. At present, the atomic spectral database of the National Institute of Standards and Technology of the United States, as the most complete spectral data library in the world, still lacks the spectral data of most high-valent ions. The spectral data of these high-valent ions are of great significance for revealing the physical properties of material materials and for future applications such as quantum information, quantum computers, and quantum time standards.

[0004] In recent years, with the continuous improvement of ion trapping and various valence ion preparation technologies, various types of ion spectral measurements have received widespread attention and have been developed and applied in scientific research and material testing.

[0005] For ion spectrum measurement, the current mainstream method is to use a spectrometer to directly collect and measure the fluorescence emitted by ions, and give the ion spectrum wavelength based on the accuracy of the spectrometer itself. The factory accuracy of the spectrometer itself is low, which limits the accuracy of spectrum line measurement. In addition, the movement and installation of the spectrometer and the system drift over time will seriously affect the accuracy of spectrum line measurement. Furthermore, the calibration lamp is used to illuminate the spectrometer at the same time to read the spectral line emitted by the calibration lamp to calibrate the ion spectrum line. However, there are many problems with the calibration method using a calibration lamp, such as the irradiation angle of the calibration lamp will affect the wavelength offset of the calibration, that is, the calibration accuracy is extremely sensitive to the position of the calibration lamp. The insufficient purity of the gas inside the calibration lamp itself will introduce stray spectra, making the spectral line emitted by the calibration lamp extremely complex. Inappropriate spectral line selection also brings calibration errors. In summary, the current error in ion fluorescence wavelength measurement is large and it is difficult to break through the picometer level. Summary of the invention

[0006] In order to solve the above problems or defects, the present invention solves the problem that the calibration in the current mainstream method is easily affected by the position of the calibration lamp and the selection of the spectral lines emitted by the calibration lamp, which limits the calibration accuracy. A high-precision calibration device for ion fluorescence wavelength measurement is provided, and a high-precision calibration method for ion fluorescence wavelength measurement is also provided.

[0007] The present invention specifically achieves the above-mentioned purpose through the following technical solutions: A high-precision calibration device for measuring ion fluorescence wavelength, comprising an ion trap. When collecting an image of ion fluorescence spectrum, an ion group is injected into the ion trap. The ion fluorescence emitted by the ion group is sequentially transmitted by a first lens group, diffusely scattered by a diffuse scattering sheet, diffracted by a filter slit, transmitted by a second lens group, and diffracted by a spectrometer slit, and then enters a grating spectrometer. The diffracted light of the ion fluorescence output by the grating spectrometer is input into an EMCCD camera. When collecting a picture of the spectrum of the light emitted by the calibration lamp, a reflector is arranged between the first lens group and the filter slit. The light emitted by the calibration lamp is reflected by the reflector, and then enters the grating spectrometer after being diffusely scattered by the diffuse scattering sheet, diffracted by the filter slit, transmitted by the second lens group, and diffracted by the spectrometer slit. The diffracted light of the light emitted by the calibration lamp output by the grating spectrometer is incident on the EMCCD camera. The diffuse scattering sheet is located on a side of the filter slit close to the first lens group; The ion groups injected into the ion trap are inert gas ions or ions to be detected.

[0008] A high-precision calibration method for ion fluorescence wavelength measurement, using the high-precision calibration device for ion fluorescence wavelength measurement as described above, comprises the following steps: Step 1: Build a high-precision calibration device for ion fluorescence wavelength measurement; Step 2, inject inert gas ions into the ion trap, and use the EMCCD camera to collect pictures of the inert gas ion fluorescence spectrum and the calibration lamp output light spectrum; based on the picture of the inert gas ion fluorescence spectrum, obtain the position coordinates of each inert gas ion fluorescence spectrum line; based on the picture of the calibration lamp output light spectrum, obtain the position coordinates of each calibration lamp output spectrum line and the corresponding calibration lamp output spectrum line wavelength; Step 3, according to the set number of auxiliary calibration spectrum lines of the calibration lamp, select multiple calibration lamp emission spectrum lines as the calibration lamp auxiliary calibration spectrum lines; The calibration lamp auxiliary calibration spectrum meets the following requirements: the position coordinates of the calibration lamp auxiliary calibration spectrum and the corresponding calibration lamp emission spectrum line wavelength are subjected to two-dimensional polynomial fitting to obtain the calibration polynomial, the position coordinates of the inert gas ion fluorescence spectrum are input into the calibration polynomial to obtain the fitted inert gas ion fluorescence wavelength corresponding to the inert gas ion fluorescence spectrum, and the fitted inert gas ion fluorescence wavelength corresponding to the inert gas ion fluorescence spectrum with a set proportion in all the inert gas ion fluorescence spectrums is consistent with the recommended value of the inert gas ion fluorescence wavelength in the NIST database; The noble gas ion fluorescence spectrum line whose fitting noble gas ion fluorescence wavelength is consistent with the recommended value of noble gas ion fluorescence wavelength in the NIST database is used as the noble gas ion assisted calibration fluorescence spectrum line; Step 4. Replace the inert gas ions in the ion trap with the ions to be measured, and use the EMCCD camera to collect images of the fluorescence spectrum of the ions to be measured. Use the calibration lamp in step 3 to assist in calibrating the spectrum lines, or use the inert gas ions to assist in calibrating the fluorescence spectrum lines, or use the calibration lamp to assist in calibrating the spectrum lines and the inert gas ions to assist in calibrating the fluorescence spectrum lines, to obtain the fluorescence wavelength measurement value of the ion to be measured corresponding to each fluorescence spectrum line of the ion to be measured in the fluorescence spectrum of the ion to be measured.

[0009] As mentioned above, step 1 includes the following steps: Step 1.1, a laser beam emitted by a laser passes through the center of the ion trap, the filter slit and the spectrometer slit in sequence and enters the grating spectrometer, and the laser output by the grating spectrometer is input to the EMCCD camera; The laser is kept on, and the first lens group is placed between the ion trap and the filter slit, and the second lens group is placed between the filter slit and the spectrometer slit; during the process of placing the first lens group and the second lens group, it is ensured that the laser reaches the same position of the EMCCD camera; Step 1.2, increase the slit width of the filter slit until only the 0th order light of the laser is emitted from the filter slit, and observe whether the imaging of the center of the ion trap coincides with the imaging of the filter slit through the EMCCD camera. If the imaging of the center of the ion trap coincides with the imaging of the filter slit, return to step 1.1; if the imaging of the center of the ion trap coincides with the imaging of the filter slit, reduce the slit width of the filter slit to the set slit width, so that the filter slit emits ±1st order light of the laser; then rotate the grating in the grating spectrometer so that the EMCCD camera detects the +1st order light or -1st order light of the grating, and turn off the laser; Step 1.3, place a reflector between the first lens group and the filter slit, place a calibration lamp in the vertical direction of the axis of the optical path from the first lens group to the filter slit, and make the calibration lamp output light reach the filter slit after being reflected by the reflector, and place a diffuse scattering sheet on the side of the filter slit close to the reflector.

[0010] The above-mentioned step 2 specifically includes the following steps: Step 2.1, injecting inert gas ions into the ion trap, moving the reflector away from between the first lens group and the filter slit, and using the EMCCD camera to collect images of the fluorescence spectrum of the inert gas ions; The reflector is moved between the first lens group and the filter slit to block the inert gas ion fluorescence emitted by the inert gas ions. The outgoing light of the calibration lamp is reflected by the reflector and then incident on the grating spectrometer. The EMCCD camera collects a picture of the spectrum of the outgoing light of the calibration lamp. Based on the image of the inert gas ion fluorescence spectrum, the position coordinates of each inert gas ion fluorescence spectrum line are obtained; based on the image of the calibration lamp output light spectrum, the position coordinates of each calibration lamp output light spectrum line are obtained; Step 2.2: Check the NIST database to find the wavelength of the spectral line emitted by the calibration lamp corresponding to the position coordinates of each spectral line emitted by the calibration lamp.

[0011] As mentioned above, step 3 includes the following steps: Step 3.1, classifying all the calibration lamp emission spectrum lines in the calibration lamp emission light spectrum into the candidate calibration spectrum line group; Step 3.2, performing two-dimensional polynomial fitting based on the position coordinates of the spectral lines emitted by the calibration lamp in the optional calibration spectral line group and the data composed of the wavelengths of the corresponding spectral lines emitted by the calibration lamp, wherein the polynomial is a cubic polynomial or a quadratic polynomial; Input the position coordinates of each noble gas ion fluorescence spectrum line obtained in step 2 into the fitted polynomial to obtain the fitted noble gas ion fluorescence wavelength corresponding to each noble gas ion fluorescence spectrum line; Step 3.3: For each noble gas ion fluorescence spectrum line, the deviation between the fitted noble gas ion fluorescence wavelength corresponding to the noble gas ion fluorescence spectrum line and the recommended value of the corresponding noble gas ion fluorescence wavelength in the NIST database value is recorded as the wavelength deviation △L g , When the wavelength deviation △L g If the number of inert gas ion fluorescence spectra within the error range divided by the total number of inert gas ion fluorescence spectra is greater than or equal to the set ratio, and the number of calibration lamp output spectra in the alternative calibration spectrum group reaches the set number of calibration lamp auxiliary calibration spectrum, execute step 3.3.1; When the wavelength deviation △L g If the number of inert gas ion fluorescence lines within the error range divided by the total number of inert gas ion fluorescence lines is less than the set ratio, execute step 3.3.2; Step 3.3.1, repeat step 2 to step 3.2 until the number of repetitions reaches the preset fitting number; For wavelength deviation △L g For each noble gas ion fluorescence spectrum within the error range, calculate the average value of all fitted noble gas ion fluorescence wavelengths obtained during the polynomial fitting process with a preset number of fitting times and standard deviation , classification of the fluorescence spectra of noble gas ions: When the corresponding recommended value of the fluorescence wavelength of the noble gas ion in the NIST database is [ ] range, it is considered that the fitted inert gas ion fluorescence wavelength corresponding to the inert gas ion fluorescence spectrum line is consistent with the recommended value of the inert gas ion fluorescence wavelength in the NIST database; When the corresponding recommended value of the noble gas ion fluorescence wavelength in the NIST database is [ ], it is considered that the fitted inert gas ion fluorescence wavelength corresponding to the inert gas ion fluorescence spectrum line does not conform to the recommended value of the inert gas ion fluorescence wavelength in the NIST database; After classifying the fluorescence spectra of the noble gas ions, execute step 4; Step 3.3.2: Remove the abnormal calibration lamp emission spectrum lines from the candidate calibration spectrum line group. If after removing the abnormal calibration lamp emission spectrum line, the number of calibration lamp emission spectrum lines in the alternative calibration spectrum line group is greater than or equal to the set minimum number of calibration lamp auxiliary calibration spectrum lines, then return to step 3.2; If after removing the abnormal calibration lamp emission spectrum line, the number of calibration lamp emission spectrum lines of the alternative calibration spectrum line group is less than the set minimum number of calibration lamp auxiliary calibration spectrum lines, the calibration lamp is replaced and the process returns to step 2; Step 3.4, when the result of dividing the number of inert gas ion fluorescence spectral lines whose fitted inert gas ion fluorescence wavelengths are consistent with the recommended value of inert gas ion fluorescence wavelength in the NIST database by the total number of inert gas ion fluorescence spectral lines is equal to or greater than the set ratio, the calibration lamp emission spectral lines in the corresponding alternative calibration spectral line group are used as calibration lamp auxiliary calibration spectral lines, and the inert gas ion fluorescence spectral lines whose fitted inert gas ion fluorescence wavelengths are consistent with the recommended value of inert gas ion fluorescence wavelength in the NIST database are used as inert gas ion auxiliary calibration fluorescence spectral lines; When the result of dividing the number of inert gas ion fluorescence lines whose fitted inert gas ion fluorescence wavelengths are consistent with the recommended value of inert gas ion fluorescence wavelengths in the NIST database by the total number of inert gas ion fluorescence lines is less than the set ratio, replace the calibration lamp or inert gas ions and return to step 2.

[0012] As mentioned above in step 3.3.2, the abnormal spectral line emitted by the calibration lamp is determined based on the following rules: For each calibration lamp output spectrum line in the candidate calibration lamp output spectrum line group, if the standardized residual of the wavelength of the corresponding calibration lamp output spectrum line is greater than 3, the corresponding calibration lamp output spectrum line is an abnormal calibration lamp output spectrum line.

[0013] As mentioned above, step 4 includes the following steps: Step 4.1, replacing the inert gas ions in the ion trap with the ions to be measured, moving the reflector out from between the first lens group and the filter slit, and collecting an image of the fluorescence spectrum of the ions to be measured by the EMCCD camera, wherein the fluorescence spectrum of the ions to be measured includes a plurality of fluorescence spectrum lines of the ions to be measured; calibrating the position coordinates of each fluorescence spectrum line of the ions to be measured in the image of the fluorescence spectrum of the ions to be measured; Step 4.2: Input the position coordinates of the fluorescence spectrum of the ion to be measured obtained in step 4.1 into the calibration polynomial obtained in step 3 to obtain the fluorescence wavelength measurement value of the ion to be measured corresponding to each fluorescence spectrum of the ion to be measured.

[0014] As mentioned above, step 4 includes the following steps: Step 4.1, replacing the inert gas ions in the ion trap with the ions to be measured, moving the reflector out from between the first lens group and the filter slit, and collecting an image of the fluorescence spectrum of the ions to be measured by the EMCCD camera, wherein the fluorescence spectrum of the ions to be measured includes a plurality of fluorescence spectral lines of the ions to be measured; Move the reflector between the first lens group and the filter slit, at which time the fluorescence of the ion to be measured is blocked, the outgoing light of the calibration lamp is incident on the grating spectrometer, and the EMCCD camera collects a picture of the spectrum of the outgoing light of the calibration lamp; Based on the image of the fluorescence spectrum of the ion to be measured, the position coordinates of each fluorescence spectrum line of the ion to be measured are obtained, and based on the image of the spectrum of the light emitted by the calibration lamp collected in step 4.1, the position coordinates of each light emitted by the calibration lamp are obtained; Step 4.2, by comparing with the NIST database, query the wavelength of the spectral line of the calibration lamp corresponding to the position coordinates of each spectral line of the calibration lamp corresponding to the image of the spectral line of the calibration lamp collected in step 4.1; Step 4.3, selecting auxiliary calibration spectrum lines, the auxiliary calibration spectrum lines include part of the calibration lamp emission spectrum lines selected from the calibration lamp emission spectrum lines of the calibration lamp obtained in step 4.1 and the synchronous calibration spectrum lines; the synchronous calibration spectrum lines are: the inert gas ion-assisted calibration fluorescence spectrum lines in step 3, or the calibration lamp auxiliary calibration spectrum lines, or the inert gas ion-assisted calibration fluorescence spectrum lines plus the calibration lamp auxiliary calibration spectrum lines; The inert gas ion fluorescence wavelength corresponding to the inert gas ion assisted calibration fluorescence spectrum line is selected from the recommended value of the inert gas ion fluorescence wavelength in the NIST database; Step 4.4, use the position coordinates of the auxiliary calibration spectrum line and the wavelength corresponding to the auxiliary calibration spectrum line to perform two-dimensional polynomial fitting to obtain the final calibration polynomial. The final calibration polynomial is a cubic polynomial or a quadratic polynomial. The position coordinates of the fluorescence spectrum line of the ion to be measured are input into the final calibration polynomial to obtain the fluorescence wavelength measurement value of each fluorescence spectrum line of the ion to be measured.

[0015] In step 2.1 and step 4.1, as described above, the reflector is moved back and forth between the first lens group and the filter slit for multiple times, and the EMCCD camera correspondingly collects pictures of the ion fluorescence spectrum line and the picture of the calibration lamp output light spectrum for multiple times in an alternating manner; the signal counts of the ion fluorescence spectrum lines at the same position coordinates in all the pictures of the ion fluorescence spectrum are accumulated or averaged to obtain a picture of the processed ion fluorescence spectrum; and the signal counts of the calibration lamp output light spectrum lines at the same position coordinates in all the pictures of the calibration lamp output light spectrum are accumulated or averaged to obtain a picture of the processed calibration lamp output light spectrum; the position coordinates of each ion fluorescence spectrum line are extracted from the picture of the processed ion fluorescence spectrum, and the position coordinates of each calibration lamp output light spectrum line are extracted from the picture of the processed calibration lamp output light spectrum; For step 2.1, the image of the ion fluorescence spectrum is the image of the inert gas ion fluorescence spectrum; the ion fluorescence spectrum line is the inert gas ion fluorescence spectrum line; For step 4.1, the picture of the ion fluorescence spectrum is the picture of the ion fluorescence spectrum to be measured; the ion fluorescence spectrum line is the ion fluorescence spectrum line to be measured.

[0016] The high-precision calibration method for ion fluorescence wavelength measurement as described above also includes the following steps: Step 5: Change the type of calibration lamp and return to step 2 until multiple fluorescence wavelength measurement values ​​of the ion to be measured are obtained for each ion fluorescence spectrum to be measured. , Indicates the serial number of the fluorescence wavelength measurement value of the ion to be measured. Each fluorescence spectrum of the ion to be measured takes the corresponding fluorescence wavelength measurement value of all the ions to be measured. The average value of the fluorescence wavelength of the ion to be measured is taken as the final measured value .

[0017] Compared with the prior art, the present invention has the following beneficial effects: The present invention can optimize the imaging optical path to make the ion fluorescence and the light emitted by the calibration lamp completely overlap at the filter slit position, effectively solving a series of calibration optical path problems in mainstream spectral calibration, such as the ion to be measured cannot completely overlap with the light emitted by the calibration lamp, the measured value of the ion fluorescence wavelength to be measured is easily affected by the position of the calibration lamp, and is sensitive to the position of the calibration lamp. It ensures that there is no angle and position offset between the calibration lamp and the ion fluorescence, and makes the calibration accuracy insensitive to the position of the calibration lamp. It greatly reduces the error caused by the placement of the calibration lamp itself to the calibration, and improves the accuracy and stability of spectral calibration.

[0018] The present invention uses the inert gas ion fluorescence spectrum as a reference for selecting the output spectrum of the calibration lamp, which can solve the problem of difficulty in selecting the output spectrum of the calibration lamp. The inert gas ion fluorescence spectrum is used to check the selection of the output spectrum of the calibration lamp, which effectively avoids the measurement error caused by inappropriate selection of the output spectrum of the calibration lamp.

[0019] The present invention provides an inert gas ion fluorescence spectrum line as an auxiliary calibration spectrum line, and combines the calibration lamp output spectrum line for calibration, which can further solve the problem that the calibration lamp output spectrum line is easily affected by other complex spectrum lines, and further improve the measurement accuracy of the fluorescence wavelength of the ion to be measured. BRIEF DESCRIPTION OF THE DRAWINGS

[0020] Figure 1 is a flow chart of the steps of the method of the present invention; Figure 2 is a schematic diagram of the calibration optical path of an embodiment of the present invention; Figure 3 This is a picture of the calibration lamp output light spectrum of the Ne lamp around 502nm-522nm measured by the EMCCD camera of an embodiment of the present invention.

[0021] Figure 4 The Ar measured by the calibration spectrum line selected by the Ne lamp at 502nm-522nm in the embodiment of the present invention + Schematic diagram of the fluorescence spectrum measurement distribution of ions.

[0022] Among them, 1-laser, 2-ion trap, 3-first lens group, 4-reflector, 5-calibration lamp, 6-diffuse scattering plate, 7-filter slit, 8-second lens group, 9-grating spectrometer, 10-spectrometer slit, 11-EMCCD camera. DETAILED DESCRIPTION

[0023] In order to make the purpose, technical solution and advantages of the present invention more clearly understood, the present invention is further described in detail below in conjunction with the accompanying drawings and specific embodiments. It should be understood that the specific embodiments described herein are only used to explain the present invention and do not constitute a limitation of the present invention.

[0024] Example 1

[0025] A high-precision calibration device for measuring ion fluorescence wavelength, comprising an ion trap 2. When collecting an image of ion fluorescence spectrum, an ion group is injected into the ion trap 2. The ion fluorescence emitted by the ion group is sequentially transmitted by a first lens group 3, diffusely scattered by a diffuse scattering sheet 6, diffracted by a filter slit 7, transmitted by a second lens group 8, and diffracted by a spectrometer slit 10, and then enters a grating spectrometer 9. The diffracted light of the ion fluorescence output by the grating spectrometer 9 is input to an EMCCD camera 11. When collecting a picture of the spectrum of the output light of the calibration lamp, a reflector 4 is arranged between the first lens group 3 and the filter slit 7, and the mirror surface of the reflector 4 forms a set angle with the axis of the optical path from the first lens group 3 to the filter slit 7; the output light of the calibration lamp 5 is reflected by the reflector 4, and then passes through the diffuse scattering of the diffuse scattering sheet 6, the diffraction of the filter slit 7, the transmission of the second lens group 8 and the diffraction of the spectrometer slit 10 in sequence, and then enters the grating spectrometer 9, and the diffracted light of the output light of the calibration lamp output by the grating spectrometer 9 is incident on the EMCCD camera 11; The ion groups injected into the ion trap 2 are inert gas ions or ions to be detected; Among them, the diffuse scattering plate 6 is located on one side of the filter slit 7 close to the first lens group 3. Through the slow scattering of the diffuse scattering plate 6, the calibration lamp output light and the ion fluorescence are both considered to be emitted from the filter slit 7, and are diffracted by the grating spectrometer 9 and then reach the EMCCD camera 11, that is, the position of the ions in the ion trap 2 and the position of the calibration lamp 5 are considered to be equivalently coincident.

[0026] In this embodiment, the ion cluster in the ion trap 2 forms an inverted image of the same size at the filter slit 7 after being transmitted through the first lens group 3; the filter slit 7 forms an inverted image of the same size at the spectrometer slit 10 after being transmitted through the second lens group 8. If the ion cluster does not form an image of the same size at the filter slit 7 and the spectrometer slit 10, but the difference is not large, it will not affect the present calibration scheme, because the essence of the present calibration scheme is that the position of the calibration lamp 5 and the position of the ion trap 2 are equivalent to one position, and the size change of the image of the ion cluster does not essentially affect the position. However, if the difference in the image of the ion cluster is large, it will inevitably affect whether the position of the calibration lamp 5 and the position of the ion trap 2 can still be equivalent to one position. For example, if the image of the ion cluster is infinitely reduced, the meaning of the filter slit 7 will be lost. The meaning of the filter slit 7 is to allow the calibration lamp 5 and the ion fluorescence to regenerate a diffraction light source that emits to the surroundings at the filter slit 7. The position information of the calibration lamp 5 and the position information of the ion trap 2 no longer affect the calibration accuracy. However, if the image of the ion cluster at the filter slit 7 is smaller than the slit width of the filter slit 7, the ion fluorescence is equivalent to directly passing through the filter slit 7 without diffraction, that is, the position and direction information of the calibration lamp 5 will affect the calibration accuracy, or the position and direction information of the ion trap 2 will affect the calibration accuracy.

[0027] Example 2

[0028] In such Figure 1 As shown, a high-precision calibration method for ion fluorescence wavelength measurement, using a high-precision calibration device for ion fluorescence wavelength measurement described in Example 1, includes the following steps: Step 1: Build a high-precision calibration device for ion fluorescence wavelength measurement, such as Figure 2 As shown, specifically: Step 1.1: Build an imaging optical path from the ion trap 2 to the grating spectrometer 9 A laser beam emitted by the laser 1 passes through the center of the ion trap 2 , the filter slit 7 and the spectrometer slit 10 in sequence and enters the grating spectrometer 9 . The laser output by the grating spectrometer 9 is input to the EMCCD camera 11 .

[0029] After the axis of the imaging optical path from the ion trap 2 to the grating spectrometer 9 is determined by laser, the axis of the optical path remains stationary (i.e., the relative positions of the ion trap 2, the filter slit 7, the spectrometer slit 10, the grating spectrometer 9, and the EMCCD camera 11 remain unchanged). Here, it is only necessary to ensure that the laser passes through the center of the ion trap 2, the filter slit 7, and the spectrometer slit 10 in sequence, and finally reaches the EMCCD camera 11. Because the ion trap 2 can emit fluorescence isotropically in any direction, slight angle changes do not affect the results.

[0030] The laser 1 remains on, the first lens group 3 is placed between the ion trap 2 and the filter slit 7, and the second lens group 8 is placed between the filter slit 7 and the spectrometer slit 10; during the process of placing the first lens group 3 and the second lens group 8, it is ensured that the laser reaches the same position of the EMCCD camera 11, thereby ensuring that all optical components are coaxial.

[0031] In this embodiment, the first lens group 3 includes two first lenses and a second lens with the same focal length; the distance between the filter slit 7 and the first lens group 3 is equal to the distance between the ion trap 2 and the first lens group 3, so that the center positions of the two symmetrical edges of the ion trap 2 form equal-sized inverted images at the filter slit 7; the second lens group 8 adopts a single lens, the focal length of the single lens is denoted as focal length f, the distance between the second lens group 8 and the filter slit 7 and the distance between the second lens group 8 and the spectrometer slit 10 are both equal to 2f; at the same time, the slit width of the filter slit 7 is increased, so that the center positions of the two symmetrical edges of the ion trap 2 form equal-sized inverted images at the spectrometer slit 10. When the ion cluster is subsequently injected into the ion trap 2, the ion cluster can form an equal-sized inverted image at the filter slit 7. After the ion fluorescence passes through the filter slit 7, it passes through the second lens group 8 to form an equal-sized upright image at the spectrometer slit 10; then the ion fluorescence enters the grating spectrometer 9 through the spectrometer slit 10, and is diffracted by the grating of the grating spectrometer 9 and emitted to the photosensitive surface of the EMCCD camera 11.

[0032] Step 1.2, increase the slit width of the filter slit 7 until only the 0th order light of the laser is emitted from the filter slit 7, and observe whether the imaging of the center of the ion trap 2 coincides with the imaging of the filter slit 7 through the EMCCD camera 11. If the imaging of the center of the ion trap 2 coincides with the imaging of the filter slit 7, return to step 1.1; if the imaging of the center of the ion trap 2 coincides with the imaging of the filter slit 7, reduce the slit width of the filter slit 7 to the set slit width, so that the filter slit 7 emits ±1st order light of the laser; then rotate the grating in the grating spectrometer 9, so that the EMCCD camera 11 detects the +1st order light or -1st order light of the grating, at this time, light of different wavelengths will be diffracted and fall on different scale positions of the photosensitive surface of the EMCCD camera 11, so as to obtain spectral information; then turn off the laser 1.

[0033] When the slit width of the filter slit 7 is increased, the ±1st order and higher order diffraction light in the laser is reduced, and the 0th order light in the laser is mainly reflected or transmitted in the grating spectrometer 9 along the direction of the incident light. Light of all wavelengths maintains the same propagation direction without any separation, so that the ion trap 2 and the filter slit 7 are imaged by the EMCCD camera 11. By observing the picture collected by the EMCCD camera 11, it is observed whether the center of the ion trap 2 is in the center of the filter slit 7.

[0034] The slit width of the filter slit 7 is adjustable between 10 microns and 1000 microns, the height of the filter slit 7 is 5 mm, and the set slit width of the filter slit 7 in this embodiment is 100 microns. In the subsequent steps, when the intensity of the ion fluorescence signal is sufficient, the slit width of the filter slit 7 and the slit width of the spectrometer slit 10 are reduced to 100 microns or less to improve the resolution of the ion fluorescence spectrum and reduce the line width of the ion fluorescence spectrum, and finally further improve the measurement accuracy of the ion fluorescence wavelength to be measured.

[0035] Step 1.3, build the optical path of the outgoing light of the calibration lamp, and optimize the spectrum signal of the outgoing light of the calibration lamp 5 to the maximum. Specifically: First, a reflector 4 is placed between the first lens group 3 and the filter slit 7. The mirror surface of the reflector 4 forms a set angle with the axis of the optical path from the first lens group 3 to the filter slit 7. In this embodiment, the set angle is 45°. The reflector 4 can be placed on a displacement frame so that it can be freely moved out of the optical path and into the optical path. A calibration lamp 5 is placed in a vertical direction to the axis of the optical path from the first lens group 3 to the filter slit 7, and the calibration lamp output light emitted by the calibration lamp 5 is reflected by the reflector 4 and reaches the center of the filter slit 7. A diffuse scattering sheet 6 is placed on the side of the filter slit 7 close to the reflector 4 so that the calibration lamp output light irradiates the filter slit 7. After reaching the diffuse scattering plate 6, it passes through the filter slit 7, so that the calibration lamp output light of the calibration lamp 5 can also be considered to be emitted from the center of the filter slit 7, and the subsequent optical path of the calibration lamp output light completely shares the subsequent optical path of ion imaging (that is, it enters the grating spectrometer 9 after being diffracted by the filter slit 7, transmitted by the second lens group 8 and diffracted by the spectrometer slit 10 in sequence, and then enters the EMCCD camera 11), so that the ion fluorescence and the calibration lamp output light are equivalently emitted from the filter slit 7, and reach the EMCCD camera 11 after being diffracted by the grating spectrometer 9, that is, it is considered that the light sources of the ion trap 2 and the calibration lamp 5 completely overlap.

[0036] Step 2, inject inert gas ions into the ion trap 2, use the EMCCD camera 11 to collect pictures of the inert gas ion fluorescence spectrum and the calibration lamp output light spectrum; obtain the position coordinates of each inert gas ion fluorescence spectrum line based on the inert gas ion fluorescence spectrum picture; obtain the position coordinates of each calibration lamp output light spectrum line and the corresponding calibration lamp output light spectrum line wavelength based on the calibration lamp output light spectrum picture. Specifically including the following steps: Step 2.1, injecting inert gas ions into the ion trap 2, moving the reflector 4 away from between the first lens group 3 and the filter slit 7, and collecting an image of the inert gas ion fluorescence spectrum with the EMCCD camera 11, wherein the inert gas ion fluorescence spectrum includes a plurality of inert gas ion fluorescence spectral lines; The reflector 4 is moved between the first lens group 3 and the filter slit 7 to block the inert gas ion fluorescence emitted by the inert gas ions. The calibration lamp 5 emits light that is reflected by the reflector 4 and then incident on the grating spectrometer 9. The EMCCD camera 11 collects a picture of the calibration lamp emitter light spectrum. The calibration lamp emitter light spectrum includes a plurality of calibration lamp emitter light spectrum lines. In this embodiment, the calibration lamp 5 uses a Ne lamp. The picture of the calibration lamp emitter light spectrum of the Ne lamp near 502nm-522nm is shown in FIG. Figure 3 As shown; The position coordinates of each inert gas ion fluorescence spectrum line are calibrated from the image of the inert gas ion fluorescence spectrum, and the position coordinates of each calibration lamp output spectrum line are calibrated from the image of the calibration lamp output light spectrum.

[0037] Step 2.2, by comparing with the NIST database, query the wavelength of the spectral line emitted by each calibration lamp corresponding to the position coordinates of the spectral line emitted by the calibration lamp, so as to obtain the data pair of the position coordinates of the spectral line emitted by the calibration lamp and the wavelength of the spectral line emitted by the calibration lamp.

[0038] The accuracy of the wavelength of the calibration lamp marked by the position coordinates of each calibration lamp's output spectrum line in the picture of the calibration lamp's output spectrum collected by the EMCCD camera 11 is low. Therefore, the calibration lamp's output spectrum is compared with the NIST database to make the position coordinates of each calibration lamp's output spectrum line corresponding to the wavelength of the calibration lamp's output spectrum line more accurate.

[0039] In step 2, the coordinates of the image of the fluorescence spectrum of the inert gas ions and the coordinates of the image of the spectrum emitted by the calibration lamp are both based on the scale coordinates of the photosensitive surface of the EMCCD camera 11 as reference coordinates.

[0040] To improve the measurement accuracy, in step 2.1 of the present embodiment, the reflector 4 is moved back and forth between the first lens group 3 and the filter slit 7 for multiple times, and the EMCCD camera 11 correspondingly collects images of the inert gas ion fluorescence spectrum and the calibration lamp output light spectrum for multiple times in an alternating manner; the signal counts of the inert gas ion fluorescence spectrum lines at the same position coordinates in all the images of the inert gas ion fluorescence spectrum are accumulated or averaged to obtain a processed image of the inert gas ion fluorescence spectrum; and the signal counts of the calibration lamp output light spectrum lines at the same position coordinates in all the images of the calibration lamp output light spectrum are accumulated or averaged to obtain a processed image of the calibration lamp output light spectrum; the position coordinates of each inert gas ion fluorescence spectrum line in the processed image of the inert gas ion fluorescence spectrum are calibrated, and the position coordinates of each calibration lamp output light spectrum line are calibrated from the processed image of the calibration lamp output light spectrum.

[0041] Step 3: According to the set number of auxiliary calibration spectrum lines of the calibration lamp, multiple calibration lamp emission spectrum lines are selected as auxiliary calibration spectrum lines of the calibration lamp; The calibration lamp auxiliary calibration spectrum meets the following requirements: the position coordinates of the calibration lamp auxiliary calibration spectrum and the corresponding calibration lamp emission spectrum line wavelength are subjected to two-dimensional polynomial fitting to obtain the calibration polynomial, the position coordinates of the inert gas ion fluorescence spectrum are input into the calibration polynomial to obtain the fitted inert gas ion fluorescence wavelength corresponding to the inert gas ion fluorescence spectrum, and the fitted inert gas ion fluorescence wavelength corresponding to the inert gas ion fluorescence spectrum with a set proportion in all the inert gas ion fluorescence spectrums is consistent with the recommended value of the inert gas ion fluorescence wavelength in the NIST database; The inert gas ion fluorescence spectrum that matches the inert gas ion fluorescence wavelength recommended value in the NIST database is used as the inert gas ion assisted calibration fluorescence spectrum. The larger the number of calibration lamp assisted calibration spectrum lines, the higher the subsequent calibration accuracy. In this embodiment, the number of calibration lamp assisted calibration spectrum lines is set to 7-20. Specifically, the following steps are included: Step 3.1, classifying all the calibration lamp emission spectrum lines in the calibration lamp emission light spectrum into the candidate calibration spectrum line group; Step 3.2, performing two-dimensional polynomial fitting based on the position coordinates of the spectral lines emitted by the calibration lamp in the optional calibration spectral line group and the data composed of the wavelengths of the corresponding spectral lines emitted by the calibration lamp, wherein the polynomial is a cubic polynomial or a quadratic polynomial; Input the position coordinates of each noble gas ion fluorescence spectrum line obtained in step 2 into the fitted polynomial to obtain the fitted noble gas ion fluorescence wavelength corresponding to each noble gas ion fluorescence spectrum line; Step 3.3, check whether the fitted noble gas ion fluorescence wavelength of each noble gas ion fluorescence spectrum line is within the error range of the recommended value of the corresponding noble gas ion fluorescence wavelength in the NIST database, specifically including the following steps: For each noble gas ion fluorescence spectrum line, the deviation between the fitted noble gas ion fluorescence wavelength corresponding to the noble gas ion fluorescence spectrum line and the recommended value of the corresponding noble gas ion fluorescence wavelength in the NIST database value is recorded as the wavelength deviation △L g , When the wavelength deviation △L g The number of inert gas ion fluorescence spectra within the error range divided by the total number of inert gas ion fluorescence spectra is greater than or equal to the set ratio, and the number of calibration lamp output spectra in the alternative calibration line group reaches the set number of calibration lamp auxiliary calibration lines. Execute step 3.3.1 to further confirm the wavelength deviation △L g Whether the fitted inert gas ion fluorescence wavelength corresponding to each inert gas ion fluorescence spectrum within the error range is consistent with the recommended value of the inert gas ion fluorescence wavelength in the NIST database; When the wavelength deviation △L gIf the number of inert gas ion fluorescence spectra within the error range divided by the total number of inert gas ion fluorescence spectra is less than the set ratio, it is possible that the fitted inert gas ion fluorescence wavelength corresponding to the inert gas ion fluorescence spectrum does not conform to the recommended value of the inert gas ion fluorescence wavelength in the NIST database, or there may be an abnormal calibration lamp emission spectrum line in the alternative calibration spectrum line group, then execute step 3.3.2; Step 3.3.1, repeat step 2 to step 3.2 until the number of repetitions reaches the preset fitting number; For wavelength deviation △L g For each noble gas ion fluorescence spectrum within the error range, calculate the average value of all fitted noble gas ion fluorescence wavelengths obtained during the polynomial fitting process with a preset number of fitting times and standard deviation , classification of the fluorescence spectra of noble gas ions: When the corresponding recommended value of the fluorescence wavelength of the noble gas ion in the NIST database is [ ] range, it is considered that the fitted inert gas ion fluorescence wavelength corresponding to the inert gas ion fluorescence spectrum line is consistent with the recommended value of the inert gas ion fluorescence wavelength in the NIST database; When the corresponding recommended value of the noble gas ion fluorescence wavelength in the NIST database is [ ], it is considered that the fitted inert gas ion fluorescence wavelength corresponding to the inert gas ion fluorescence spectrum line does not conform to the recommended value of the inert gas ion fluorescence wavelength in the NIST database; After classifying the fluorescence spectra of the noble gas ions, execute step 4; Step 3.3.2: Remove the abnormal calibration lamp emission spectrum lines from the candidate calibration spectrum line group. If after removing the abnormal calibration lamp emission spectrum line, the number of calibration lamp emission spectrum lines in the alternative calibration spectrum line group is greater than or equal to the set minimum number of calibration lamp auxiliary calibration spectrum lines, then return to step 3.2; If after removing the abnormal calibration lamp emission spectrum line, the number of calibration lamp emission spectrum lines of the alternative calibration spectrum line group is less than the set minimum number of calibration lamp auxiliary calibration spectrum lines, it means that the calibration lamp emission spectrum lines corresponding to the selected calibration lamp 5 are insufficient, then the calibration lamp 5 is replaced and the process returns to step 2; Step 3.4, when the result of dividing the number of inert gas ion fluorescence spectral lines whose fitted inert gas ion fluorescence wavelengths are consistent with the recommended value of inert gas ion fluorescence wavelength in the NIST database by the total number of inert gas ion fluorescence spectral lines is equal to or greater than the set ratio (the set ratio in this embodiment is 50%), the calibration lamp emission spectral lines in the corresponding alternative calibration spectral line group are used as the calibration lamp auxiliary calibration spectral lines, and the inert gas ion fluorescence spectral lines whose fitted inert gas ion fluorescence wavelengths are consistent with the recommended value of inert gas ion fluorescence wavelength in the NIST database are used as inert gas ion auxiliary calibration fluorescence spectral lines; When the result of dividing the number of inert gas ion fluorescence lines whose fitted inert gas ion fluorescence wavelengths are consistent with the recommended value of inert gas ion fluorescence wavelengths in the NIST database by the total number of inert gas ion fluorescence lines does not reach the set ratio, replace the calibration lamp 5 or the inert gas ions and return to step 2.

[0042] In step 3.3.2, the abnormal spectral line emitted by the calibration lamp is determined based on the following rules: For each calibration lamp emission spectrum line in the candidate calibration spectrum line group, if the standardized residual of the corresponding calibration lamp emission spectrum line wavelength is greater than 3, the corresponding calibration lamp emission spectrum line is an abnormal calibration lamp emission spectrum line (that is, the position coordinates of the calibration lamp emission spectrum line are input into the fitted polynomial to obtain the calibration lamp emission spectrum line wavelength fitting value, and the deviation between the calibration lamp emission spectrum line wavelength fitting value and the corresponding calibration lamp emission spectrum line wavelength is recorded as the residual error △L of the calibration lamp emission spectrum line wavelength q The standard deviation of the residual of the wavelength of the spectral line emitted by the calibration lamp is recorded as S q , the standardized residual of the wavelength of the spectral line emitted by the calibration lamp is △L q / S q , when △L q / S q >3, the corresponding calibration lamp emission spectrum line is an abnormal calibration lamp emission spectrum line); The calibration lamp 5 selected in step 2 and the calibration lamp 5 replaced in steps 3.5 and 3.6 must all meet the following requirements: the calibration lamp 5 corresponds to an estimated spectral range R c Estimated spectral range R covering noble gas ions g The ratio of the estimated spectral range R c and the estimated spectral range R of the noble gas ions g The width of the overlapping wavelength interval and the estimated spectral range R of the noble gas ions g The ratio of the corresponding wavelength interval width is greater than or equal to the preset coverage range threshold lower limit (the preset coverage range threshold lower limit is 90% in this embodiment), and the calibration lamp estimates the spectral range R c Covering the estimated spectral range R of the ion to be detectedt The ratio of the estimated spectral range R c and the estimated spectral range R of the ion to be detected t The width of the overlapping wavelength interval is related to the estimated spectral range R of the ion to be measured. t The ratio of the corresponding wavelength interval width is greater than or equal to the preset coverage range threshold lower limit. c The wavelength range from the minimum value to the maximum value of the wavelength of the spectral line emitted by the selected calibration lamp 5 is estimated; the spectral range R of the inert gas ion g is the wavelength range from the estimated minimum to the estimated maximum value of the fluorescence wavelength of the inert gas ion; the spectral range R of the ion to be measured t It is the wavelength range from the estimated minimum value to the estimated maximum value of the fluorescence wavelength of the ion to be measured.

[0043] Step 4: Replace the inert gas ions in the ion trap 2 with the ions to be measured, and the EMCCD camera 11 collects a picture of the fluorescence spectrum of the ions to be measured. Use the calibration lamp in step 3 to assist in calibrating the spectrum lines, or use the inert gas ions to assist in calibrating the fluorescence spectrum lines, or use the calibration lamp to assist in calibrating the spectrum lines and the inert gas ions to assist in calibrating the fluorescence spectrum lines, to obtain the fluorescence wavelength measurement value of the ion to be measured corresponding to each fluorescence spectrum line of the ion to be measured in the fluorescence spectrum of the ion to be measured.

[0044] Solution 1: Step 4.1, replace the inert gas ions in the ion trap 2 with the ions to be measured, move the reflector 4 out from between the first lens group 3 and the filter slit 7, and collect a picture of the fluorescence spectrum of the ions to be measured by the EMCCD camera 11, wherein the fluorescence spectrum of the ions to be measured includes a plurality of fluorescence spectrum lines of the ions to be measured; calibrate the position coordinates of each fluorescence spectrum line of the ions to be measured in the picture of the fluorescence spectrum of the ions to be measured; Step 4.2: Input the position coordinates of the fluorescence spectrum of the ion to be measured obtained in step 4.1 into the calibration polynomial obtained in step 3 to obtain the fluorescence wavelength measurement value of the ion to be measured corresponding to each fluorescence spectrum of the ion to be measured.

[0045] Since the position coordinates of the inert gas ion-assisted calibration fluorescence spectrum in step 3 and the corresponding recommended value of the inert gas ion fluorescence wavelength in the NIST database satisfy the calibration polynomial, the position coordinates of the calibration lamp-assisted calibration spectrum and the corresponding calibration lamp emission spectrum line wavelength also satisfy the calibration polynomial, Scheme 1 can directly input the position coordinates of the ion fluorescence spectrum to be measured into the calibration polynomial obtained in step 3 to obtain the corresponding ion fluorescence wavelength measurement value to be measured. The accuracy of this scheme will be affected by factors that change slowly over time (such as temperature and vibration).

[0046] Option 2: Step 4.1, replace the inert gas ions in the ion trap 2 with the ions to be measured, move the reflector 4 out from between the first lens group 3 and the filter slit 7, and collect the image of the fluorescence spectrum of the ions to be measured by the EMCCD camera 11, the fluorescence spectrum of the ions to be measured includes a plurality of fluorescence spectral lines of the ions to be measured; Move the reflector 4 between the first lens group 3 and the filter slit 7. At this time, the fluorescence of the ion to be measured is blocked, and the outgoing light of the calibration lamp 5 is incident on the grating spectrometer 9. The EMCCD camera 11 collects a picture of the spectrum of the outgoing light of the calibration lamp. Based on the image of the fluorescence spectrum of the ion to be measured, the position coordinates of each fluorescence spectrum line of the ion to be measured are obtained, and based on the image of the spectrum of the light emitted by the calibration lamp collected in step 4.1, the position coordinates of each light emitted by the calibration lamp are obtained; To improve the measurement accuracy, in step 4.1 of the present embodiment, the reflector 4 is moved back and forth between the first lens group 3 and the filter slit 7 for multiple times, and the EMCCD camera 11 correspondingly and alternately collects images of the fluorescence spectrum of the ion to be measured and the image of the light spectrum emitted by the calibration lamp for multiple times; the signal counts of the fluorescence spectrum of the ion to be measured at the same position coordinates in all the images of the fluorescence spectrum of the ion to be measured are accumulated or averaged to obtain the processed image of the fluorescence spectrum of the ion to be measured; and the signal counts of the light spectrum emitted by the calibration lamp at the same position coordinates in all the images of the light spectrum emitted by the calibration lamp collected in step 4.1 are accumulated or averaged to obtain the corresponding processed image of the light spectrum emitted by the calibration lamp; the position coordinates of each fluorescence spectrum of the ion to be measured are extracted from the processed image of the fluorescence spectrum of the ion to be measured. By reciprocatingly and alternately collecting images of the fluorescence spectrum of the ion to be measured and the light spectrum emitted by the calibration lamp and then accumulating (or averaging) them respectively, the drift of the calibration device over time caused by other possible problems such as slow changes in ambient temperature and vibration can be avoided or reduced, thereby affecting the final result. For example, assuming that temperature changes cause the position coordinates of the spectral lines to gradually increase, when using reciprocating alternating measurements, the position coordinates of the spectral lines emitted by the calibration lamp and the position coordinates of the fluorescence of the ions to be measured will both be larger. This is equivalent to using the spectral lines emitted by the calibration lamp to calibrate the fluorescence spectral lines of the ions to be measured, and the larger deviation will be offset.

[0047] Step 4.2, refer to the NIST database to query the wavelength of the calibration lamp output spectrum line corresponding to the position coordinates of each calibration lamp output spectrum line corresponding to the image of the calibration lamp output spectrum collected in step 4.1. In order to eliminate the influence of any factors that may change slowly over time, the calibration lamp output spectrum is measured again in step 4.1 of scheme 2; Step 4.3, selecting auxiliary calibration spectrum lines, the auxiliary calibration spectrum lines include part of the calibration lamp emission spectrum lines selected from the calibration lamp emission spectrum lines of the calibration lamp 5 obtained in step 4.1 and synchronous calibration spectrum lines; wherein the number of auxiliary calibration spectrum lines reaches the set number of auxiliary calibration spectrum lines of the calibration lamp, and the synchronous calibration spectrum lines are: the inert gas ion-assisted calibration fluorescence spectrum line in step 3, or the calibration lamp auxiliary calibration spectrum line, or the inert gas ion-assisted calibration fluorescence spectrum line plus the calibration lamp auxiliary calibration spectrum line; The inert gas ion fluorescence wavelength corresponding to the inert gas ion assisted calibration fluorescence spectrum line is selected from the recommended value of the inert gas ion fluorescence wavelength in the NIST database; Step 4.4, use the position coordinates of the auxiliary calibration spectrum line and the wavelength corresponding to the auxiliary calibration spectrum line to perform two-dimensional polynomial fitting to obtain the final calibration polynomial. The final calibration polynomial is a cubic polynomial or a quadratic polynomial. The position coordinates of the fluorescence spectrum line of the ion to be measured are input into the final calibration polynomial to obtain the fluorescence wavelength measurement value of each fluorescence spectrum line of the ion to be measured.

[0048] To measure the fluorescence spectrum of the ion to be measured within a certain range, it is usually necessary to have at least 4 or more spectral lines emitted by the calibration lamp. However, for the inert gas ions in step 4, there may not be enough inert gas ion-assisted calibration fluorescence lines within the spectral range of the fluorescence spectrum of the ion to be measured. Therefore, using the inert gas ion fluorescence lines alone as auxiliary calibration lines may not be possible in some cases. Generally, the more auxiliary calibration lines there are, the higher the relative calibration accuracy will be. By simultaneously adding the inert gas ion-assisted calibration fluorescence lines and the calibration lamp-assisted calibration lines, the measurement results of the fluorescence wavelength of the ion to be measured are more reliable and have a higher confidence level, and high-precision measurement of the fluorescence wavelength of the ion to be measured can be achieved. The error of the fluorescence wavelength of the ion to be measured obtained by Scheme 2 is determined by the measurement error of the calibration lamp-emitting spectral lines, the measurement error of the inert gas ion fluorescence lines, and the error of the optical path of the calibration device.

[0049] In this embodiment, the fluorescence spectrum of the inert gas ions is Ar + Ion fluorescence spectra.

[0050] As a further optimization, multiple groups of inert gas ion-assisted calibration fluorescence spectra are obtained to calibrate the fluorescence spectra of the ions to be measured respectively. This embodiment also includes the following steps: Step 5: Change the type of calibration lamp 5, and return to step 2 until each ion fluorescence spectrum to be measured obtains multiple ion fluorescence wavelength measurement values ​​to be measured. , Indicates the serial number of the fluorescence wavelength measurement value of the ion to be measured. Each fluorescence spectrum of the ion to be measured takes the corresponding fluorescence wavelength measurement value of all the ions to be measured. The average value of the fluorescence wavelength of the ion to be measured is taken as the final measured value .

[0051] For each fluorescence spectrum of the ion to be measured, the following method can be used to check whether the calibration accuracy of the fluorescence wavelength of the ion to be measured meets the calibration accuracy requirement: For the same fluorescence spectrum of the ion to be measured, calculate the measured values ​​of the fluorescence wavelength of the ion to be measured after two calibrations. The deviation between them is taken as the fluorescence wavelength deviation of the ion to be measured. When the fluorescence wavelength deviation of the ion to be measured is less than the wavelength deviation judgment threshold, it indicates that the calibration accuracy of the fluorescence wavelength of the ion to be measured meets the calibration accuracy requirement.

[0052] Types of the proofreading lamp 5 include Ne lamp, Kr lamp, Hg lamp and Pt lamp.

[0053] like Figure 4 As shown, the spectral line of the calibration lamp selected by the Ne lamp in the vicinity of 502nm-522nm is measured in the range of 505nm to 510nm by Ar + Schematic diagram of the numerical distribution of the fluorescence wavelength of the noble gas ions corresponding to the ion fluorescence spectrum. The measured central value of 509.04954 (26) nm is consistent with the recommended value of 509.04948 (3) nm for the fluorescence wavelength of the noble gas ions in the NIST database. The inspection accuracy is better than picometers and reaches the order of hundreds of femtometers.

[0054] As a further optimization, a variety of inert gases such as Ar, He, Rn, Xe, etc. are selected for testing to obtain more inert gas ion fluorescence spectra as auxiliary calibration spectra to improve the calibration accuracy.

[0055] In this embodiment, the slit width of the filter slit 7 is reduced to 50 microns, and the slit width of the spectrometer slit 10 is reduced to 30 microns, thereby improving the resolution of the fluorescence spectrum and reducing the line width of the fluorescence spectrum, and ultimately further improving the calibration accuracy of the fluorescence wavelength of the ion to be measured.

[0056] Although the embodiments of the present invention have been shown and described above, it is to be understood that the above embodiments are merely illustrative of the principles and effects of the present invention, and are not intended to limit the present invention. A person of ordinary skill in the art may modify or change the above embodiments within the scope of the present invention. Therefore, any other corresponding changes and modifications made according to the technical concept of the present invention that do not depart from the technical concept of the present invention should be included in the protection scope of the claims of the present invention.

[0057] The contents not described in detail in the specification of the present invention belong to the common knowledge of the professionals in this field.

Claims

1. A high-precision calibration device for measuring ion fluorescence wavelength, comprising an ion trap (2), characterized in that: When collecting an image of the ion fluorescence spectrum, an ion group is injected into the ion trap (2), and the ion fluorescence emitted by the ion group is sequentially transmitted by the first lens group (3), diffusely scattered by the diffuse scattering plate (6), diffracted by the filter slit (7), transmitted by the second lens group (8), and diffracted by the spectrometer slit (10), and then enters the grating spectrometer (9). The diffracted light of the ion fluorescence output by the grating spectrometer (9) is input into the EMCCD camera (11); When collecting an image of the spectrum of the output light of the calibration lamp, a reflector (4) is arranged between the first lens group (3) and the filter slit (7); the output light of the calibration lamp emitted by the calibration lamp (5) is reflected by the reflector (4), and then passes through the diffuse scattering of the diffuse scattering sheet (6), the diffraction of the filter slit (7), the transmission of the second lens group (8), and the diffraction of the spectrometer slit (10) in sequence, and then enters the grating spectrometer (9); the diffracted light of the output light of the calibration lamp output by the grating spectrometer (9) is incident on the EMCCD camera (11); The diffuse scattering sheet (6) is located on a surface of the filter slit (7) close to the first lens group (3); The ion group injected into the ion trap (2) is an inert gas ion or an ion to be detected.

2. A high-precision calibration method for ion fluorescence wavelength measurement, using the high-precision calibration device for ion fluorescence wavelength measurement according to claim 1, characterized in that: The following steps are involved: Step 1: Build a high-precision calibration device for ion fluorescence wavelength measurement; Step 2, injecting inert gas ions into the ion trap (2), and using an EMCCD camera (11) to collect images of the fluorescence spectrum of the inert gas ions and the spectrum of the light emitted by the calibration lamp; Based on the image of the inert gas ion fluorescence spectrum, the position coordinates of each inert gas ion fluorescence spectrum line are obtained; based on the image of the calibration lamp output light spectrum, the position coordinates of each calibration lamp output light spectrum line and the corresponding calibration lamp output light spectrum line wavelength are obtained; Step 3, according to the set number of auxiliary calibration spectrum lines of the calibration lamp, select multiple calibration lamp emission spectrum lines as auxiliary calibration spectrum lines of the calibration lamp; The calibration lamp auxiliary calibration spectrum meets the following requirements: the position coordinates of the calibration lamp auxiliary calibration spectrum and the corresponding calibration lamp emission spectrum line wavelength are subjected to two-dimensional polynomial fitting to obtain the calibration polynomial, the position coordinates of the inert gas ion fluorescence spectrum are input into the calibration polynomial to obtain the fitted inert gas ion fluorescence wavelength corresponding to the inert gas ion fluorescence spectrum, and the fitted inert gas ion fluorescence wavelength corresponding to the inert gas ion fluorescence spectrum with a set proportion in all the inert gas ion fluorescence spectrums is consistent with the recommended value of the inert gas ion fluorescence wavelength in the NIST database; The noble gas ion fluorescence spectrum line whose fitting noble gas ion fluorescence wavelength is consistent with the recommended value of noble gas ion fluorescence wavelength in the NIST database is used as the noble gas ion assisted calibration fluorescence spectrum line; Step 4, replace the inert gas ions in the ion trap (2) with the ions to be measured, and use the EMCCD camera (11) to collect an image of the fluorescence spectrum of the ions to be measured, and use the calibration lamp in step 3 to assist in calibrating the spectrum lines, or use the inert gas ions to assist in calibrating the fluorescence spectrum lines, or use the calibration lamp to assist in calibrating the spectrum lines and the inert gas ions to assist in calibrating the fluorescence spectrum lines, to obtain the fluorescence wavelength measurement value of the ions to be measured corresponding to each fluorescence spectrum line of the ions to be measured in the fluorescence spectrum of the ions to be measured.

3. A high-precision calibration method for ion fluorescence wavelength measurement according to claim 2, characterized in that: The step 1 comprises the following steps: Step 1.1, a laser beam emitted by a laser (1) passes through the center of an ion trap (2), a filter slit (7), and a spectrometer slit (10) in sequence and enters a grating spectrometer (9), and the laser beam output by the grating spectrometer (9) is input to an EMCCD camera (11); The laser (1) is kept turned on, a first lens group (3) is placed between the ion trap (2) and the filter slit (7), and a second lens group (8) is placed between the filter slit (7) and the spectrometer slit (10); during the process of placing the first lens group (3) and the second lens group (8), it is ensured that the laser reaches the same position of the EMCCD camera (11); Step 1.2, increase the slit width of the filter slit (7) until only the 0th order light of the laser is emitted from the filter slit (7), and observe whether the imaging of the center of the ion trap (2) and the imaging of the filter slit (7) coincide with each other through the EMCCD camera (11). If the imaging of the center of the ion trap (2) and the imaging of the filter slit (7) do not coincide with each other, return to step 1.1; if the imaging of the center of the ion trap (2) and the imaging of the filter slit (7) coincide with each other, reduce the slit width of the filter slit (7) to the set slit width, so that the filter slit (7) emits ±1st order light of the laser; then rotate the grating in the grating spectrometer (9) so that the EMCCD camera (11) detects the +1st order light or -1st order light of the grating, and turn off the laser (1); Step 1.3, place a reflector (4) between the first lens group (3) and the filter slit (7), place a calibration lamp (5) in a direction perpendicular to the axis of the optical path from the first lens group (3) to the filter slit (7), and make the calibration lamp output light emitted by the calibration lamp (5) reach the filter slit (7) after being reflected by the reflector (4), and place a diffuse scattering sheet (6) on the side of the filter slit (7) close to the reflector (4).

4. A high-precision calibration method for ion fluorescence wavelength measurement according to claim 2, characterized in that: The step 2 specifically includes the following steps: Step 2.1, inert gas ions are injected into the ion trap (2), the reflector (4) is moved away from between the first lens group (3) and the filter slit (7), and the EMCCD camera (11) collects images of the fluorescence spectrum of the inert gas ions; The reflector (4) is moved between the first lens group (3) and the filter slit (7) so that the inert gas ion fluorescence emitted by the inert gas ions is blocked, and the calibration lamp output light of the calibration lamp (5) is reflected by the reflector (4) and then incident on the grating spectrometer (9), and the EMCCD camera (11) collects a picture of the spectrum of the calibration lamp output light; Based on the image of the inert gas ion fluorescence spectrum, the position coordinates of each inert gas ion fluorescence spectrum line are obtained; based on the image of the calibration lamp output light spectrum, the position coordinates of each calibration lamp output light spectrum line are obtained; Step 2.2: Check the NIST database to find the wavelength of the spectral line emitted by the calibration lamp corresponding to the position coordinates of each spectral line emitted by the calibration lamp.

5. A high-precision calibration method for ion fluorescence wavelength measurement according to claim 3, characterized in that: The step 3 comprises the following steps: Step 3.1, classifying all the calibration lamp emission spectrum lines in the calibration lamp emission light spectrum into the candidate calibration spectrum line group; Step 3.2, performing two-dimensional polynomial fitting based on the position coordinates of the spectral lines emitted by the calibration lamp in the optional calibration spectral line group and the data composed of the wavelengths of the corresponding spectral lines emitted by the calibration lamp, wherein the polynomial is a cubic polynomial or a quadratic polynomial; Input the position coordinates of each noble gas ion fluorescence spectrum line obtained in step 2 into the fitted polynomial to obtain the fitted noble gas ion fluorescence wavelength corresponding to each noble gas ion fluorescence spectrum line; Step 3.3: For each noble gas ion fluorescence spectrum line, the deviation between the fitted noble gas ion fluorescence wavelength corresponding to the noble gas ion fluorescence spectrum line and the recommended value of the corresponding noble gas ion fluorescence wavelength in the NIST database value is recorded as the wavelength deviation △L g , When the wavelength deviation △L g If the number of inert gas ion fluorescence spectra within the error range divided by the total number of inert gas ion fluorescence spectra is greater than or equal to the set ratio, and the number of calibration lamp output spectra in the alternative calibration spectrum group reaches the set number of calibration lamp auxiliary calibration spectrum, execute step 3.3.1; When the wavelength deviation △L g If the number of inert gas ion fluorescence lines within the error range divided by the total number of inert gas ion fluorescence lines is less than the set ratio, execute step 3.3.2; Step 3.3.1, repeat step 2 to step 3.2 until the number of repetitions reaches the preset fitting number; For wavelength deviation △L g For each noble gas ion fluorescence spectrum within the error range, calculate the average value of all fitted noble gas ion fluorescence wavelengths obtained during the polynomial fitting process with a preset number of fitting times and standard deviation , classification of the fluorescence spectra of noble gas ions: When the corresponding recommended value of the fluorescence wavelength of the noble gas ion in the NIST database is [ ] range, it is considered that the fitted inert gas ion fluorescence wavelength corresponding to the inert gas ion fluorescence spectrum line is consistent with the recommended value of the inert gas ion fluorescence wavelength in the NIST database; When the corresponding recommended value of the noble gas ion fluorescence wavelength in the NIST database is [ ], it is considered that the fitted inert gas ion fluorescence wavelength corresponding to the inert gas ion fluorescence spectrum line does not conform to the recommended value of the inert gas ion fluorescence wavelength in the NIST database; After classifying the fluorescence spectra of the noble gas ions, execute step 4; Step 3.3.2: Remove the abnormal calibration lamp emission spectrum lines from the candidate calibration spectrum line group. If after removing the abnormal calibration lamp emission spectrum line, the number of calibration lamp emission spectrum lines in the alternative calibration spectrum line group is greater than or equal to the set minimum number of calibration lamp auxiliary calibration spectrum lines, then return to step 3.2; If, after removing the abnormal calibration lamp emission spectrum line, the number of calibration lamp emission spectrum lines in the alternative calibration spectrum line group is less than the set minimum number of calibration lamp auxiliary calibration spectrum lines, the calibration lamp is replaced (5) and the process returns to step 2; Step 3.4, when the result of dividing the number of inert gas ion fluorescence spectral lines whose fitted inert gas ion fluorescence wavelengths are consistent with the recommended value of inert gas ion fluorescence wavelength in the NIST database by the total number of inert gas ion fluorescence spectral lines is equal to or greater than the set ratio, the calibration lamp emission spectral lines in the corresponding alternative calibration spectral line group are used as calibration lamp auxiliary calibration spectral lines, and the inert gas ion fluorescence spectral lines whose fitted inert gas ion fluorescence wavelengths are consistent with the recommended value of inert gas ion fluorescence wavelength in the NIST database are used as inert gas ion auxiliary calibration fluorescence spectral lines; When the result of dividing the number of inert gas ion fluorescence lines whose fitted inert gas ion fluorescence wavelengths match the recommended value of inert gas ion fluorescence wavelengths in the NIST database by the total number of inert gas ion fluorescence lines is less than the set ratio, replace the calibration lamp (5) or the inert gas ions and return to step 2.

6. A high-precision calibration method for ion fluorescence wavelength measurement according to claim 5, characterized in that: In step 3.3.2, the abnormal spectral line emitted by the calibration lamp is determined based on the following rules: For each calibration lamp output spectrum line in the candidate calibration lamp output spectrum line group, if the standardized residual of the wavelength of the corresponding calibration lamp output spectrum line is greater than 3, the corresponding calibration lamp output spectrum line is an abnormal calibration lamp output spectrum line.

7. A high-precision calibration method for ion fluorescence wavelength measurement according to claim 5, characterized in that: The step 4 comprises the following steps: Step 4.1, replacing the inert gas ions in the ion trap (2) with the ions to be measured, moving the reflector (4) out from between the first lens group (3) and the filter slit (7), and using the EMCCD camera (11) to collect an image of the fluorescence spectrum of the ions to be measured, wherein the fluorescence spectrum of the ions to be measured includes a plurality of fluorescence spectrum lines of the ions to be measured; and calibrating the position coordinates of each fluorescence spectrum line of the ions to be measured in the image of the fluorescence spectrum of the ions to be measured; Step 4.2: Input the position coordinates of the fluorescence spectrum of the ion to be measured obtained in step 4.1 into the calibration polynomial obtained in step 3 to obtain the fluorescence wavelength measurement value of the ion to be measured corresponding to each fluorescence spectrum of the ion to be measured.

8. A high-precision calibration method for ion fluorescence wavelength measurement according to claim 5, characterized in that: The step 4 comprises the following steps: Step 4.1, replacing the inert gas ions in the ion trap (2) with the ions to be measured, moving the reflector (4) out from between the first lens group (3) and the filter slit (7), and collecting an image of the fluorescence spectrum of the ions to be measured by the EMCCD camera (11), wherein the fluorescence spectrum of the ions to be measured includes a plurality of fluorescence spectral lines of the ions to be measured; The reflector (4) is moved between the first lens group (3) and the filter slit (7), whereby the fluorescence of the ion to be measured is blocked, and the calibration lamp (5) emits light incident on the grating spectrometer (9), and the EMCCD camera (11) collects an image of the spectrum of the calibration lamp emits light; Based on the image of the fluorescence spectrum of the ion to be measured, the position coordinates of each fluorescence spectrum line of the ion to be measured are obtained, and based on the image of the spectrum of the light emitted by the calibration lamp collected in step 4.1, the position coordinates of each light emitted by the calibration lamp are obtained; Step 4.2, by comparing with the NIST database, query the wavelength of the spectral line of the calibration lamp corresponding to the position coordinates of each spectral line of the calibration lamp corresponding to the image of the spectral line of the calibration lamp collected in step 4.1; Step 4.3, selecting auxiliary calibration spectrum lines, the auxiliary calibration spectrum lines include part of the calibration lamp emission spectrum lines selected from the calibration lamp emission spectrum lines of the calibration lamp (5) obtained in step 4.1 and synchronous calibration spectrum lines; the synchronous calibration spectrum lines are: the inert gas ion-assisted calibration fluorescence spectrum lines in step 3, or the calibration lamp-assisted calibration spectrum lines, or the inert gas ion-assisted calibration fluorescence spectrum lines plus the calibration lamp-assisted calibration spectrum lines; The inert gas ion fluorescence wavelength corresponding to the inert gas ion assisted calibration fluorescence spectrum line is selected from the recommended value of the inert gas ion fluorescence wavelength in the NIST database; Step 4.4, use the position coordinates of the auxiliary calibration spectrum line and the wavelength corresponding to the auxiliary calibration spectrum line to perform two-dimensional polynomial fitting to obtain the final calibration polynomial. The final calibration polynomial is a cubic polynomial or a quadratic polynomial. The position coordinates of the fluorescence spectrum line of the ion to be measured are input into the final calibration polynomial to obtain the fluorescence wavelength measurement value of each fluorescence spectrum line of the ion to be measured.

9. A high-precision calibration method for ion fluorescence wavelength measurement according to claim 8, characterized in that: The reflector (4) described in step 2.1 and step 4.1 is repeatedly moved out and in between the first lens group (3) and the filter slit (7), and the EMCCD camera (11) correspondingly collects images of the ion fluorescence spectrum and the calibration lamp output light spectrum in a correspondingly alternating manner for multiple times; the signal counts of the ion fluorescence spectrum lines at the same position coordinates in all the images of the ion fluorescence spectrum are accumulated or averaged to obtain a processed image of the ion fluorescence spectrum; and the signal counts of the calibration lamp output light spectrum lines at the same position coordinates in all the images of the calibration lamp output light spectrum are accumulated or averaged to obtain a processed image of the calibration lamp output light spectrum; the position coordinates of each ion fluorescence spectrum line are extracted from the processed image of the ion fluorescence spectrum, and the position coordinates of each calibration lamp output light spectrum line are extracted from the processed image of the calibration lamp output light spectrum; For step 2.1, the image of the ion fluorescence spectrum is the image of the inert gas ion fluorescence spectrum; the ion fluorescence spectrum line is the inert gas ion fluorescence spectrum line; For step 4.1, the picture of the ion fluorescence spectrum is the picture of the ion fluorescence spectrum to be measured; the ion fluorescence spectrum line is the ion fluorescence spectrum line to be measured.

10. A high-precision calibration method for ion fluorescence wavelength measurement according to claim 2, characterized in that: The following steps are also included: Step 5: Change the type of calibration lamp (5), and return to step 2 until multiple fluorescence wavelength measurement values ​​of the ion to be measured are obtained for each fluorescence spectrum of the ion to be measured. , Indicates the serial number of the fluorescence wavelength measurement value of the ion to be measured. Each fluorescence spectrum of the ion to be measured takes the corresponding fluorescence wavelength measurement value of all the ions to be measured. The average value of the fluorescence wavelength of the ion to be measured is taken as the final measured value .

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