A high-precision calibration device and method for measuring ion fluorescence wavelength

Abstract

The present invention discloses a high-precision calibration device for measuring ion fluorescence wavelengths, which images ions onto a filter slit through a lens group, and diffusely scatters the emitted light of the calibration lamp to a diffraction slit through a reflector and a diffuse scattering plate, thereby coinciding with the ion fluorescence emission area. The present invention also discloses a high-precision calibration method for measuring ion fluorescence wavelengths, which optimizes the selection of the emission spectrum line of the calibration lamp using the known wavelength of inert gas ions, calibrates the fluorescence wavelength of the ion to be measured using the optimized emission spectrum line of the calibration lamp, and simultaneously assists the calibration with the spectrum line of the inert gas, thereby achieving high-precision calibration of the fluorescence wavelength of the ion to be measured. The present invention effectively solves the problem of poor measurement accuracy or measurement error of the ion spectrum to be measured due to inaccurate or inappropriate selection of the emission spectrum line of the calibration lamp, and effectively avoids calibration errors caused by the inability of the calibration light to completely coincide with the fluorescence emitted by the ions, ultimately greatly improving the precision and accuracy of spectral measurement.

Description

Technical Field

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

[0002] Spectroscopic measurements are of great significance in many fields of science and technology. For example, spectral measurements provide a means of studying the internal structure of matter, such as electronic energy levels, molecular vibrational and rotational states, and so on. Spectral analysis can reveal the energy structure and transitions of atoms and molecules, revealing the physical properties of matter. In quantum mechanics, spectral measurements are used to verify fundamental physical laws and quantum phenomena, such as quantum state transitions and the interaction of light and matter. Precise spectral measurements can test existing theories and advance the exploration of new physics. Spectroscopic measurements can also identify the composition of a substance by analyzing the light it emits or absorbs. Each element or molecule has a unique spectral "fingerprint," and analyzing these fingerprints can determine the identity of the element or molecule in a sample.

[0003] At present, the spectral databases of atoms, ions, etc. of various materials have been continuously improved with the development of science and technology. In particular, the transition wavelength data of noble gas atoms and monovalent ions have very high precision, generally reaching picometers or even femtometers. However, the spectral data of some atoms and ions are still lacking or the precision 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 comprehensive 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 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 spectrometer itself has low factory accuracy, which limits the accuracy of spectral line measurement. In addition, the movement and installation of the spectrometer, as well as the system drift over time, seriously affect the accuracy of spectral line measurement. A further method is to use a calibration lamp to illuminate the spectrometer at the same time to read the calibration lamp's emitted spectrum line to calibrate the ion spectrum line. However, there are also many problems with the calibration method using a calibration lamp, such as the angle of the calibration lamp will affect the calibration wavelength offset, 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 calibration lamp's emitted spectrum line 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] The present invention aims to solve the above-mentioned problems or defects, and to solve 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:

[0008] A high-precision calibration device for ion fluorescence wavelength measurement includes an ion trap. When collecting images of the ion fluorescence spectrum, ion clusters are injected into the ion trap. The ion fluorescence emitted by the ion clusters is sequentially transmitted by a first lens group, diffusely scattered by a diffuse scattering plate, diffracted by a filter slit, transmitted by a second lens group, and diffracted by a spectrometer slit before entering a grating spectrometer. The diffracted light of the ion fluorescence output by the grating spectrometer is input into an EMCCD camera.

[0009] When collecting an image of the spectrum of the light emitted by the marking lamp, a reflector is set between the first lens group and the filter slit. The light emitted by the marking lamp is reflected by the reflector, and then passes through the diffuse scattering of the diffuse scattering plate, diffraction of the filter slit, transmission of the second lens group, and diffraction of the spectrometer slit before entering the grating spectrometer. The diffracted light of the light emitted by the marking lamp output by the grating spectrometer is incident on the EMCCD camera.

[0010] The diffuse scattering plate is located on a side of the filter slit close to the first lens group;

[0011] The ion clusters injected into the ion trap are inert gas ions or ions to be detected.

[0012] 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:

[0013] Step 1: Build a high-precision calibration device for ion fluorescence wavelength measurement;

[0014] Step 2: Inject inert gas ions into the ion trap and use an EMCCD camera to collect images 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 image of the inert gas ion fluorescence spectrum; 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 image of the calibration lamp output light spectrum;

[0015] Step 3: According to the set number of auxiliary calibration lines of the calibration lamp, multiple calibration lamp emission spectrum lines are selected as auxiliary calibration lines of the calibration lamp;

[0016] 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 output spectrum line wavelength are subjected to two-dimensional polynomial fitting to obtain a 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 a set proportion of inert gas ion fluorescence spectrum lines among all inert gas ion fluorescence spectrum lines is consistent with the recommended value of inert gas ion fluorescence wavelength in the NIST database;

[0017] The noble gas ion fluorescence spectrum line whose fitted 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;

[0018] 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.

[0019] As mentioned above, step 1 includes the following steps:

[0020] 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. The laser output from the grating spectrometer is input to the EMCCD camera;

[0021] The laser remains 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 placement of the first and second lens groups, the laser beam is ensured to reach the same position on the EMCCD camera.

[0022] Step 1.2: Increase the slit width of the filter until only zero-order laser light is emitted from the filter slit. Use the EMCCD camera to observe whether the image of the center of the ion trap overlaps with the image of the filter slit. If not, return to step 1.1. If the image of the center of the ion trap overlaps with the image of the filter slit, reduce the slit width of the filter to the set slit width so that the filter slit emits ±1-order laser light. Then, rotate the grating in the grating spectrometer so that the EMCCD camera detects the +1-order or -1-order laser light from the grating, and turn off the laser.

[0023] 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 light emitted by the calibration lamp 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.

[0024] The above-mentioned step 2 specifically includes the following steps:

[0025] Step 2.1: Inject noble gas ions into the ion trap, remove the reflector from between the first lens group and the filter slit, and use the EMCCD camera to capture images of the noble gas ion fluorescence spectrum.

[0026] Move the reflector 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 marking lamp is reflected by the reflector and then incident on the grating spectrometer. The EMCCD camera collects an image of the spectrum of the outgoing light of the marking lamp.

[0027] Based on the image of the noble gas ion fluorescence spectrum, the position coordinates of each noble 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;

[0028] Step 2.2: Query the NIST database to find the wavelength of each calibration lamp's emitted spectrum line corresponding to the position coordinates of each calibration lamp's emitted spectrum line.

[0029] Step 3 as described above includes the following steps:

[0030] 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;

[0031] Step 3.2, performing a two-dimensional polynomial fitting based on the position coordinates of the calibration lamp output spectrum lines in the alternative calibration spectrum line group and the corresponding calibration lamp output spectrum line wavelength data, wherein the polynomial is a cubic polynomial or a quadratic polynomial;

[0032] 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;

[0033] Step 3.3: For each noble gas ion fluorescence line, the deviation between the fitted noble gas ion fluorescence wavelength corresponding to the noble gas ion fluorescence line and the recommended value of the noble gas ion fluorescence wavelength in the NIST database is recorded as the wavelength deviation △L. g ,

[0034] When the wavelength deviation △L g If the number of noble gas ion fluorescence lines within the error range divided by the total number of noble gas ion fluorescence lines is greater than or equal to the set ratio, and the number of calibration lamp output spectral lines in the alternative calibration line group reaches the set number of calibration lamp auxiliary calibration lines, proceed to step 3.3.1.

[0035] When the wavelength deviation △L g If the number of noble gas ion fluorescence lines within the error range divided by the total number of noble gas ion fluorescence lines is less than the set ratio, proceed to step 3.3.2.

[0036] Step 3.3.1: Repeat steps 2 to 3.2 until the number of repetitions reaches the preset number of fitting times;

[0037] For wavelength deviation △L g For each noble gas ion fluorescence spectrum line 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 noble gas ion fluorescence spectra:

[0038] When the corresponding recommended value of the noble gas ion fluorescence wavelength in the NIST database is [ ] range, it is considered that the fitted noble gas ion fluorescence wavelength corresponding to the noble gas ion fluorescence spectrum line is consistent with the recommended value of the noble gas ion fluorescence wavelength in the NIST database;

[0039] When the NIST database value corresponds to the recommended value of the noble gas ion fluorescence wavelength in [ ] range, it is considered that the fitted noble gas ion fluorescence wavelength corresponding to the noble gas ion fluorescence spectrum line does not conform to the recommended value of the noble gas ion fluorescence wavelength in the NIST database;

[0040] After classifying the noble gas ion fluorescence spectra, proceed to step 3.4;

[0041] Step 3.3.2: Remove the abnormal calibration lamp emission spectrum lines from the candidate calibration spectrum line group.

[0042] 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;

[0043] 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, replace the calibration lamp and return to step 2;

[0044] Step 3.4. When the result of dividing the number of noble gas ion fluorescence spectral lines whose fitted noble gas ion fluorescence wavelengths are consistent with the recommended values of noble gas ion fluorescence wavelengths in the NIST database by the total number of noble 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 the calibration lamp auxiliary calibration spectral lines, and the noble gas ion fluorescence spectral lines whose fitted noble gas ion fluorescence wavelengths are consistent with the recommended values of noble gas ion fluorescence wavelengths in the NIST database are used as the noble gas ion auxiliary calibration fluorescence spectral lines;

[0045] 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 ion and return to step 2.

[0046] As mentioned above in step 3.3.2, the abnormal calibration lamp emission spectrum line is determined based on the following rules:

[0047] For each calibration lamp output spectrum line in the alternative calibration lamp spectrum line group, if the standardized residual of the corresponding calibration lamp output spectrum line wavelength is greater than 3, the corresponding calibration lamp output spectrum line is an abnormal calibration lamp output spectrum line.

[0048] Step 4 as described above includes the following steps:

[0049] Step 4.1. Replace the noble gas ions in the ion trap with the ions to be measured, remove the reflector from between the first lens group and the filter slit, and use the EMCCD camera to capture an image of the fluorescence spectrum of the ions to be measured, the fluorescence spectrum of the ions to be measured including multiple fluorescence spectral lines of the ions to be measured; and calibrate the position coordinates of each fluorescence spectral line of the ions to be measured in the image of the fluorescence spectrum of the ions to be measured.

[0050] 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.

[0051] Step 4 as described above includes the following steps:

[0052] Step 4.1, replacing the noble gas ions in the ion trap with the ions to be measured, removing the reflector from between the first lens group and the filter slit, and capturing an image of the fluorescence spectrum of the ions to be measured with an EMCCD camera. The fluorescence spectrum of the ions to be measured includes multiple fluorescence spectral lines of the ions to be measured;

[0053] Move the reflector between the first lens group and the filter slit. At this time, the fluorescence of the ion to be measured is blocked, and the outgoing light of the calibration lamp is incident on the grating spectrometer. The EMCCD camera collects the image of the spectrum of the outgoing light of the calibration lamp.

[0054] Obtain the position coordinates of each fluorescence spectrum line of the ion to be measured based on the image of the fluorescence spectrum of the ion to be measured, and obtain the position coordinates of each spectral line emitted by the calibration lamp based on the image of the spectrum of the calibration lamp emitted in step 4.1;

[0055] Step 4.2: Query the NIST database to find the wavelength of the calibration lamp's output spectrum line corresponding to the position coordinates of each calibration lamp's output spectrum line corresponding to the image of the calibration lamp's output spectrum collected in step 4.1;

[0056] Step 4.3, selecting auxiliary calibration spectra, the auxiliary calibration spectra including a portion of the calibration lamp emission spectra selected from the calibration lamp emission spectra obtained in step 4.1 and synchronous calibration spectra; the synchronous calibration spectra are: the inert gas ion-assisted calibration fluorescence spectra in step 3, or the calibration lamp-assisted calibration spectra, or the inert gas ion-assisted calibration fluorescence spectra plus the calibration lamp-assisted calibration spectra;

[0057] The inert gas ion fluorescence wavelength corresponding to the inert gas ion assisted calibration fluorescence spectrum is selected from the recommended value of the inert gas ion fluorescence wavelength in the NIST database;

[0058] 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. Input the position coordinates of the fluorescence spectrum line of the ion to be measured into the final calibration polynomial to obtain the fluorescence wavelength measurement value of the ion to be measured for each fluorescence spectrum line of the ion to be measured.

[0059] In step 2.1 and step 4.1, as described above, the reflector is moved back and forth multiple times between the first lens group and the filter slit, and the EMCCD camera correspondingly collects pictures of the ion fluorescence spectrum line and the picture of the calibration lamp output light spectrum 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;

[0060] For step 2.1, the ion fluorescence spectrum image is the image of the noble gas ion fluorescence spectrum; the ion fluorescence spectrum line is the noble gas ion fluorescence spectrum line;

[0061] For step 4.1, the image of the ion fluorescence spectrum is the image of the fluorescence spectrum of the ion to be measured; and the ion fluorescence spectrum line is the fluorescence spectrum line of the ion to be measured.

[0062] The high-precision calibration method for ion fluorescence wavelength measurement as described above further includes the following steps:

[0063] Step 5: Change the type of calibration lamp and return to step 2 until multiple fluorescence wavelength measurements of each ion to be measured are obtained. , 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 measurement value .

[0064] Compared with the prior art, the present invention has the following beneficial effects:

[0065] The present invention optimizes the imaging optical path to completely overlap the ion fluorescence and the light emitted by the calibration lamp at the filter slit position. This effectively solves a series of calibration optical path problems in mainstream spectral calibration, such as the inability of the measured ion to completely overlap with the light emitted by the calibration lamp, the susceptibility of the measured ion fluorescence wavelength to the position of the calibration lamp, and the sensitivity to the calibration lamp position. This ensures that there is no angular or positional offset between the calibration lamp and the ion fluorescence, and makes the calibration accuracy insensitive to the calibration lamp position. This greatly reduces the error caused by the placement of the calibration lamp itself, improving the accuracy and stability of spectral calibration.

[0066] The present invention utilizes the fluorescence spectrum of inert gas ions as a reference for selecting the output spectrum of the marking lamp, resolving the difficulty in selecting the output spectrum of the marking lamp. By using the fluorescence spectrum of inert gas ions to inversely check the selection of the output spectrum of the marking lamp, measurement errors caused by inappropriate selection of the output spectrum of the marking lamp are effectively avoided.

[0067] The present invention provides an inert gas ion fluorescence spectrum line as an auxiliary calibration spectrum line, and combines it with 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

[0068] Figure 1 It is a flow chart of the steps of the method of the present invention;

[0069] Figure 2 Schematic diagram of the calibration optical path according to an embodiment of the present invention;

[0070] Figure 3 This is a picture of the spectrum of the calibration lamp light emitted by the Ne lamp near 502nm-522nm measured by the EMCCD camera of an embodiment of the present invention.

[0071] 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.

[0072] Among them, 1-laser, 2-ion trap, 3-first lens group, 4-reflecting mirror, 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

[0073] In order to make the purpose, technical solutions and advantages of the present invention more clearly understood, the present invention will be 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.

[0074] Example 1

[0075] A high-precision calibration device for ion fluorescence wavelength measurement includes an ion trap 2. When collecting an image of the ion fluorescence spectrum, an ion cluster is injected into the ion trap 2. The ion fluorescence emitted by the ion cluster is sequentially transmitted by a first lens group 3, diffusely scattered by a diffuse scattering plate 6, diffracted by a filter slit 7, transmitted by a second lens group 8, and diffracted by a spectrometer slit 10 before entering a grating spectrometer 9. The diffracted light of the ion fluorescence output by the grating spectrometer 9 is input into an EMCCD camera 11.

[0076] When collecting an image of the spectrum of the light emitted by 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 calibration lamp light emitted by the calibration lamp 5 is reflected by the reflector 4, and then passes through the diffuse scattering of the diffuse scattering plate 6, the diffraction of the filter slit 7, the transmission of the second lens group 8, and the diffraction of the spectrometer slit 10, and then enters the grating spectrometer 9. The diffracted light of the calibration lamp light output by the grating spectrometer 9 is incident on the EMCCD camera 11;

[0077] The ion clusters injected into the ion trap 2 are inert gas ions or ions to be detected;

[0078] Among them, the diffuse scattering plate 6 is located on the side of the filter slit 7 close to the first lens group 3. Through the slow scattering of the diffuse scattering plate 6, the output light of the calibration lamp 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.

[0079] In this embodiment, after the ion cluster in the ion trap 2 passes through the first lens group 3, it forms an inverted image of the same size at the filter slit 7; after the filter slit 7 passes through the second lens group 8, it forms an inverted image of the same size at the spectrometer slit 10. 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 significant, it will not affect the calibration scheme, because the essence of the 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 ion cluster image 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 in all directions in 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.

[0080] Example 2

[0081] In such Figure 1 As shown, a high-precision calibration method for ion fluorescence wavelength measurement, using the high-precision calibration device for ion fluorescence wavelength measurement described in Example 1, includes the following steps:

[0082] Step 1: Build a high-precision calibration device for ion fluorescence wavelength measurement, such as Figure 2 As shown, specifically:

[0083] Step 1.1: Build the imaging optical path from the ion trap 2 to the grating spectrometer 9

[0084] 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 .

[0085] After using laser light to determine the axis of the imaging optical path from ion trap 2 to grating spectrometer 9, the axis of the optical path remains stationary (i.e., the relative positions of ion trap 2, filter slit 7, spectrometer slit 10, grating spectrometer 9, and EMCCD camera 11 remain unchanged). Here, it is sufficient to ensure that the laser light passes through the center of ion trap 2, filter slit 7, spectrometer slit 10, and ultimately reaches EMCCD camera 11. Because the ion trap 2 can emit fluorescence isotropically in any direction, slight angle changes do not affect the results.

[0086] The laser 1 remains on, and 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 placement of 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.

[0087] In this embodiment, the first lens group 3 includes a first lens and a second lens having 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 centers 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 is a single lens, the focal length of which 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 centers 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.

[0088] 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. Use the EMCCD camera 11 to observe whether the imaging of the center of the ion trap 2 coincides with the imaging of the filter slit 7. If the imaging of the center of the ion trap 2 does not coincide 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 to obtain spectral information. Then turn off the laser 1.

[0089] 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 both imaged by the EMCCD camera 11. By observing the image captured 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.

[0090] The slit width of filter slit 7 is adjustable between 10 microns and 1000 microns. The height of filter slit 7 is 5 mm. In this embodiment, the set slit width of filter slit 7 is 100 microns. In subsequent steps, when the ion fluorescence signal intensity is sufficient, the slit width of filter slit 7 and the slit width of 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, ultimately further improving the measurement accuracy of the ion fluorescence wavelength to be measured.

[0091] Step 1.3: Build the optical path of the outgoing light of the marking lamp, and optimize the spectrum signal of the outgoing light of the marking lamp 5 to the maximum. Specifically:

[0092] 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 of 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. 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.

[0093] Step 2: Inject inert gas ions into the ion trap 2 and use the EMCCD camera 11 to collect images of the inert gas ion fluorescence spectrum and the calibration lamp output light spectrum. The position coordinates of each inert gas ion fluorescence spectrum line are obtained based on the inert gas ion fluorescence spectrum image. The position coordinates of each calibration lamp output light spectrum line and the corresponding calibration lamp output light spectrum line wavelength are obtained based on the calibration lamp output light spectrum image. The specific steps include:

[0094] Step 2.1: Inject noble gas ions into the ion trap 2, remove the reflector 4 from between the first lens group 3 and the filter slit 7, and use the EMCCD camera 11 to capture an image of the noble gas ion fluorescence spectrum, wherein the noble gas ion fluorescence spectrum includes multiple noble gas ion fluorescence lines;

[0095] 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 enters the grating spectrometer 9. The EMCCD camera 11 collects a picture of the calibration lamp's emitted light spectrum. The calibration lamp's emitted light spectrum includes multiple calibration lamp emitted light spectrum lines. In this embodiment, the calibration lamp 5 uses a Ne lamp. The picture of the calibration lamp's emitted light spectrum near 502nm-522nm of the Ne lamp is as shown in FIG. Figure 3 As shown;

[0096] The position coordinates of each noble gas ion fluorescence spectrum line are calibrated from the image of the noble 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.

[0097] Step 2.2: Query the wavelength of each calibration lamp's spectral line corresponding to its position coordinates by comparing it with the NIST database, thereby obtaining a data pair of the position coordinates and wavelength of each calibration lamp's spectral line.

[0098] The accuracy of the calibration lamp wavelength marked by the position coordinates of each calibration lamp output spectrum line in the picture of the calibration lamp output light spectrum collected by the EMCCD camera 11 is low. Therefore, the calibration lamp output light spectrum is compared with the NIST database to make the position coordinates of each calibration lamp output spectrum line corresponding to the obtained calibration lamp output spectrum line wavelength more accurate.

[0099] The coordinates of the image of the inert gas ion fluorescence spectrum and the image of the calibration lamp emission spectrum in step 2 are both based on the scale coordinates of the photosensitive surface of the EMCCD camera 11 as reference coordinates.

[0100] In order to improve the measurement accuracy, in step 2.1 of this embodiment, the reflector 4 is moved back and forth between the first lens group 3 and the filter slit 7 multiple times, and the EMCCD camera 11 correspondingly collects pictures of the inert gas ion fluorescence spectrum and the calibration lamp output light spectrum 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 pictures of the inert gas ion fluorescence spectrum are accumulated or averaged to obtain a picture of the processed 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 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 inert gas ion fluorescence spectrum line are calibrated from the picture of the processed inert gas ion fluorescence spectrum, and the position coordinates of each calibration lamp output light spectrum line are calibrated from the picture of the processed calibration lamp output light spectrum.

[0101] Step 3: According to the set number of auxiliary calibration lines of the calibration lamp, select multiple calibration lamp emission spectrum lines as auxiliary calibration lines of the calibration lamp;

[0102] 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 output spectrum line wavelength are subjected to two-dimensional polynomial fitting to obtain a 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 a set proportion of inert gas ion fluorescence spectrum lines among all inert gas ion fluorescence spectrum lines is consistent with the recommended value of inert gas ion fluorescence wavelength in the NIST database;

[0103] The noble gas ion fluorescence spectra whose fitted noble gas ion fluorescence wavelengths match the recommended values of noble gas ion fluorescence wavelengths in the NIST database are used as noble gas ion-assisted calibration fluorescence spectra. The greater the number of calibration lamp-assisted calibration spectra, the higher the subsequent calibration accuracy. In this embodiment, the number of calibration lamp-assisted calibration spectra is set to 7-20. The specific steps include:

[0104] 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;

[0105] Step 3.2, performing a two-dimensional polynomial fitting based on the position coordinates of the calibration lamp output spectrum lines in the alternative calibration spectrum line group and the corresponding calibration lamp output spectrum line wavelength data, wherein the polynomial is a cubic polynomial or a quadratic polynomial;

[0106] 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;

[0107] 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, including the following steps:

[0108] For each noble gas ion fluorescence line, the deviation between the fitted noble gas ion fluorescence wavelength corresponding to the noble gas ion fluorescence line and the recommended value of the noble gas ion fluorescence wavelength in the NIST database is recorded as the wavelength deviation △L g ,

[0109] When the wavelength deviation △L gThe number of inert gas ion fluorescence lines within the error range divided by the total number of inert gas ion fluorescence lines is greater than or equal to the set ratio, and the number of calibration lamp output spectrum lines in the alternative calibration line group reaches the set number of calibration lamp auxiliary calibration spectrum lines. Perform step 3.3.1 to further confirm the wavelength deviation △L g Whether the fitted noble gas ion fluorescence wavelengths corresponding to the noble gas ion fluorescence lines within the error range are consistent with the recommended values of noble gas ion fluorescence wavelengths in the NIST database;

[0110] When the wavelength deviation △L g If the number of noble gas ion fluorescence lines within the error range divided by the total number of noble gas ion fluorescence lines is less than the set ratio, it is possible that the fitted noble gas ion fluorescence wavelength corresponding to the noble gas ion fluorescence line does not match the recommended noble 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. In this case, proceed to step 3.3.2.

[0111] Step 3.3.1: Repeat steps 2 to 3.2 until the number of repetitions reaches the preset number of fitting times;

[0112] For wavelength deviation △L g For each noble gas ion fluorescence spectrum line 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 noble gas ion fluorescence spectra:

[0113] When the corresponding recommended value of the noble gas ion fluorescence wavelength in the NIST database is [ ] range, it is considered that the fitted noble gas ion fluorescence wavelength corresponding to the noble gas ion fluorescence spectrum line is consistent with the recommended value of the noble gas ion fluorescence wavelength in the NIST database;

[0114] When the NIST database value corresponds to the recommended value of the noble gas ion fluorescence wavelength in [ ] range, it is considered that the fitted noble gas ion fluorescence wavelength corresponding to the noble gas ion fluorescence spectrum line does not conform to the recommended value of the noble gas ion fluorescence wavelength in the NIST database;

[0115] After classifying the noble gas ion fluorescence spectra, proceed to step 3.4;

[0116] Step 3.3.2: Remove the abnormal calibration lamp emission spectrum lines from the candidate calibration spectrum line group.

[0117] 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;

[0118] If, after removing the abnormal calibration lamp emission spectrum lines, 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, 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;

[0119] Step 3.4: When the number of noble gas ion fluorescence spectral lines whose fitted noble gas ion fluorescence wavelengths match the recommended noble gas ion fluorescence wavelengths in the NIST database divided by the total number of noble gas ion fluorescence spectral lines is equal to or greater than a set ratio (the set ratio is 50% in this embodiment), 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 noble gas ion fluorescence spectral lines whose fitted noble gas ion fluorescence wavelengths match the recommended noble gas ion fluorescence wavelengths in the NIST database are used as the noble gas ion auxiliary calibration fluorescence spectral lines;

[0120] 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 ion and return to step 2.

[0121] In step 3.3.2, the abnormal spectral line emitted by the calibration lamp is determined based on the following rules:

[0122] For each calibration lamp output spectrum line in the alternative calibration spectrum line group, if the standardized residual of the corresponding calibration lamp output spectrum line wavelength is greater than 3, the corresponding calibration lamp output spectrum line is an abnormal calibration lamp output spectrum line (that is, the position coordinates of the calibration lamp output spectrum line are input into the fitted polynomial to obtain the calibration lamp output spectrum line wavelength fitting value, and the deviation between the calibration lamp output spectrum line wavelength fitting value and the corresponding calibration lamp output spectrum line wavelength is recorded as the calibration lamp output spectrum line wavelength residual △L 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);

[0123] 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 the estimated spectral range R c Estimated spectral range R covering noble gas ions g The ratio of the estimated spectral range of the calibration lamp R c and the estimated spectral range R of 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 Estimated spectral range R covering the ion to be measured t The ratio of the estimated spectral range of the calibration lamp R c and the estimated spectral range R of the ion to be measured t The width of the overlapping wavelength interval is consistent with 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 threshold. c The wavelength range of the selected calibration lamp 5 corresponding to the estimated minimum to maximum wavelength of the calibration lamp emission spectrum line; the spectral range R of the inert gas ion g The wavelength range of the fluorescence wavelength of the inert gas ion is from the estimated minimum value to the estimated maximum value; the spectral range of the ion to be measured is R t The wavelength range is from the estimated minimum to the estimated maximum value of the fluorescence wavelength of the ion to be measured.

[0124] 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, and uses the calibration lamp in step 3 to assist in calibrating the spectrum lines or uses the inert gas ions to assist in calibrating the fluorescence spectrum lines or uses 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.

[0125] Option 1:

[0126] Step 4.1. Replace the noble gas ions in the ion trap 2 with the ions to be measured, remove the reflector 4 from between the first lens group 3 and the filter slit 7, and use the EMCCD camera 11 to capture an image of the fluorescence spectrum of the ion to be measured, where the fluorescence spectrum includes multiple fluorescence lines of the ion to be measured; and calibrate the position coordinates of each fluorescence line of the ion to be measured in the image of the fluorescence spectrum of the ion to be measured.

[0127] 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.

[0128] Since the position coordinates of the inert gas ion-assisted calibration fluorescence line in step 3 and the corresponding recommended inert gas ion fluorescence wavelength in the NIST database satisfy the calibration polynomial, the position coordinates of the calibration lamp-assisted calibration line and the corresponding calibration lamp output spectrum line wavelength also satisfy the calibration polynomial. Therefore, in solution 1, the position coordinates of the ion fluorescence line to be measured can be directly input into the calibration polynomial obtained in step 3 to obtain the corresponding ion fluorescence wavelength measurement value. The accuracy of this solution can be affected by factors that change slowly over time, such as temperature and vibration.

[0129] Option 2:

[0130] Step 4.1: Replace the noble gas ions in the ion trap 2 with the ions to be measured, remove the reflector 4 from between the first lens group 3 and the filter slit 7, and use the EMCCD camera 11 to capture an image of the fluorescence spectrum of the ions to be measured, where the fluorescence spectrum of the ions to be measured includes multiple fluorescence spectral lines of the ions to be measured;

[0131] 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 marking lamp 5 is incident on the grating spectrometer 9. The EMCCD camera 11 collects an image of the spectrum of the outgoing light of the marking lamp.

[0132] Obtain the position coordinates of each fluorescence spectrum line of the ion to be measured based on the image of the fluorescence spectrum of the ion to be measured, and obtain the position coordinates of each spectral line emitted by the calibration lamp based on the image of the spectrum of the calibration lamp emitted in step 4.1;

[0133] To improve measurement accuracy, in step 4.1 of this embodiment, the reflector 4 is repeatedly moved back and forth between the first lens group 3 and the filter slit 7, and the EMCCD camera 11 repeatedly and alternately captures images of the fluorescence spectrum of the ion to be measured and images of the calibration lamp's output light spectrum. The signal counts of the fluorescence spectrum of the ion to be measured at the same position coordinates in all images of the fluorescence spectrum of the ion to be measured are accumulated or averaged to obtain a processed image of the fluorescence spectrum of the ion to be measured. Furthermore, the signal counts of the calibration lamp's output light spectrum at the same position coordinates in all images of the calibration lamp's output light spectrum collected in step 4.1 are accumulated or averaged to obtain a corresponding processed image of the calibration lamp's output light spectrum. The position coordinates of each fluorescence spectrum line to be measured are extracted from the processed image of the fluorescence spectrum of the ion to be measured. This reciprocating and alternating capture of images of the fluorescence spectrum of the ion to be measured and images of the calibration lamp's output light spectrum, followed by accumulation (or averaging) of these images, can avoid or reduce the impact of drift of the calibration device over time due to other potential issues, such as slow changes in ambient temperature and vibration, which can affect the final results. 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.

[0134] Step 4.2: Query the NIST database to find the wavelength of each calibration lamp's output spectrum line corresponding to the coordinates of each calibration lamp's output spectrum line, as found in the image of the calibration lamp's output spectrum collected in Step 4.1. To eliminate the influence of any factors that may change slowly over time, measure the calibration lamp's output spectrum again in Step 4.1 of Solution 2.

[0135] Step 4.3, selecting auxiliary calibration spectra, the auxiliary calibration spectra including part of the calibration lamp emission spectra selected from the calibration lamp emission spectra of the calibration lamp 5 obtained in step 4.1 and the synchronous calibration spectra; wherein the number of auxiliary calibration spectra reaches the set number of calibration lamp auxiliary calibration spectra, and the synchronous calibration spectra are: the inert gas ion-assisted calibration fluorescence spectra in step 3, or the calibration lamp auxiliary calibration spectra, or the inert gas ion-assisted calibration fluorescence spectra plus the calibration lamp auxiliary calibration spectra;

[0136] The inert gas ion fluorescence wavelength corresponding to the inert gas ion assisted calibration fluorescence spectrum is selected from the recommended value of the inert gas ion fluorescence wavelength in the NIST database;

[0137] 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. Input the position coordinates of the fluorescence spectrum line of the ion to be measured into the final calibration polynomial to obtain the fluorescence wavelength measurement value of the ion to be measured for each fluorescence spectrum line of the ion to be measured.

[0138] 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 auxiliary 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 auxiliary calibration fluorescence lines and the calibration lamp auxiliary 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 emission spectrum line, the measurement error of the inert gas ion fluorescence lines, and the error of the optical path of the calibration device.

[0139] In this embodiment, the fluorescence spectrum of the inert gas ion is Ar + Ion fluorescence spectra.

[0140] As a further optimization, multiple sets of inert gas ion-assisted calibration fluorescence spectra are obtained to calibrate the fluorescence spectra of the ions to be measured respectively. This embodiment further includes the following steps:

[0141] Step 5: Change the type of calibration lamp 5 and return to step 2 until multiple fluorescence wavelength measurement values of each ion to be measured are obtained. , 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 measurement value .

[0142] 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 requirements: For the same fluorescence spectrum of the ion to be measured, calculate the pairwise calibration of the fluorescence wavelength of the ion to be measured. 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.

[0143] Types of the proofreading lamp 5 include Ne lamp, Kr lamp, Hg lamp and Pt lamp.

[0144] like Figure 4 As shown in the figure, the spectral line of the calibration lamp selected by this embodiment using Ne lamp at 502nm-522nm is measured in the range of 505nm to 510nm. + Schematic diagram of the numerical distribution of the fluorescence wavelengths of 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 noble gas ions in the NIST database, and the test accuracy is better than picometers, reaching the order of hundreds of femtometers.

[0145] As a further optimization, a variety of inert gases such as Ar, He, Rn, Xe, etc. were selected for testing to obtain more inert gas ion fluorescence spectra as auxiliary calibration spectra to improve the calibration accuracy.

[0146] 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.

[0147] Although the embodiments of the present invention have been shown and described above, it should 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. Those skilled in the art may modify or alter the above embodiments within the scope of the present invention. Therefore, any other corresponding changes and modifications made based on the technical concept of the present invention that do not depart from the technical concept of the present invention should be included within the scope of protection of the claims of the present invention.

[0148] The contents not described in detail in the specification of the present invention belong to the common knowledge of professionals in this field.

Claims

1. A high-precision calibration method for ion fluorescence wavelength measurement, characterized in that: The following steps are involved: Step 1: Build a high-precision calibration device for ion fluorescence wavelength measurement; Step 2: Inject inert gas ions into the ion trap (2), and use the 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 noble gas ion fluorescence spectrum, the position coordinates of each noble 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 lines of the calibration lamp, multiple calibration lamp emission spectrum lines are selected as auxiliary calibration 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 output spectrum line wavelength are subjected to two-dimensional polynomial fitting to obtain a 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 a set proportion of inert gas ion fluorescence spectrum lines among all inert gas ion fluorescence spectrum lines is consistent with the recommended value of inert gas ion fluorescence wavelength in the NIST database; The noble gas ion fluorescence spectrum line whose fitted 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 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 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.

2. A high-precision calibration method for ion fluorescence wavelength measurement according to claim 1, characterized in that: The step 1 comprises the following steps: Step 1.1, 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), and the laser output from the grating spectrometer (9) is input to the EMCCD camera (11); The laser (1) is kept on, and 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).

3. 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, 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 images of the fluorescence spectrum of the inert gas ions using the EMCCD camera (11); 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 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 noble gas ion fluorescence spectrum, the position coordinates of each noble 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: Query the NIST database to find the wavelength of each calibration lamp's emitted spectrum line corresponding to the position coordinates of each calibration lamp's emitted spectrum line.

4. 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 a two-dimensional polynomial fitting based on the position coordinates of the calibration lamp output spectrum lines in the alternative calibration spectrum line group and the corresponding calibration lamp output spectrum line wavelength data, 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 line, the deviation between the fitted noble gas ion fluorescence wavelength corresponding to the noble gas ion fluorescence line and the recommended value of the noble gas ion fluorescence wavelength in the NIST database is recorded as the wavelength deviation △L. g , When the wavelength deviation △L g If the number of noble gas ion fluorescence lines within the error range divided by the total number of noble gas ion fluorescence lines is greater than or equal to the set ratio, and the number of calibration lamp output spectral lines in the alternative calibration line group reaches the set number of calibration lamp auxiliary calibration lines, proceed to step 3.3.

1. When the wavelength deviation △L g If the number of noble gas ion fluorescence lines within the error range divided by the total number of noble gas ion fluorescence lines is less than the set ratio, proceed to step 3.3.

2. Step 3.3.1: Repeat steps 2 to 3.2 until the number of repetitions reaches the preset number of fitting times; For wavelength deviation △L g For each noble gas ion fluorescence spectrum line 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 noble gas ion fluorescence spectra: When the corresponding recommended value of the noble gas ion fluorescence wavelength in the NIST database is [ ] range, it is considered that the fitted noble gas ion fluorescence wavelength corresponding to the noble gas ion fluorescence spectrum line is consistent with the recommended value of the noble gas ion fluorescence wavelength in the NIST database; When the NIST database value corresponds to the recommended value of the noble gas ion fluorescence wavelength in [ ] range, it is considered that the fitted noble gas ion fluorescence wavelength corresponding to the noble gas ion fluorescence spectrum line does not conform to the recommended value of the noble gas ion fluorescence wavelength in the NIST database; After classifying the noble gas ion fluorescence spectra, proceed to step 3.4; 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, then replace the calibration lamp (5) and return to step 2; Step 3.

4. When the result of dividing the number of noble gas ion fluorescence spectral lines whose fitted noble gas ion fluorescence wavelengths are consistent with the recommended values of noble gas ion fluorescence wavelengths in the NIST database by the total number of noble 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 the calibration lamp auxiliary calibration spectral lines, and the noble gas ion fluorescence spectral lines whose fitted noble gas ion fluorescence wavelengths are consistent with the recommended values of noble gas ion fluorescence wavelengths in the NIST database are used as the noble gas ion auxiliary calibration fluorescence spectral lines; When the result of dividing the number of noble gas ion fluorescence lines whose fitted noble gas ion fluorescence wavelengths are consistent with the recommended value of noble gas ion fluorescence wavelengths in the NIST database by the total number of noble gas ion fluorescence lines is less than the set ratio, replace the calibration lamp (5) or the noble gas ions and return to step 2.

5. A high-precision calibration method for ion fluorescence wavelength measurement according to claim 4, 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 alternative calibration lamp spectrum line group, if the standardized residual of the corresponding calibration lamp output spectrum line wavelength is greater than 3, the corresponding calibration lamp output spectrum line is an abnormal calibration lamp output spectrum line.

6. 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 ion to be measured, the fluorescence spectrum of the ion to be measured including a plurality of fluorescence spectrum lines of the ion to be measured; calibrating the position coordinates of each fluorescence spectrum line of the ion to be measured in the image of the fluorescence spectrum of the ion 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.

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, the fluorescence spectrum of the ions to be measured including 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), at which time the fluorescence of the ion to be measured is blocked, and the calibration lamp (5) output light is incident on the grating spectrometer (9), and the EMCCD camera (11) collects a picture of the calibration lamp output light spectrum; Obtain the position coordinates of each fluorescence spectrum line of the ion to be measured based on the image of the fluorescence spectrum of the ion to be measured, and obtain the position coordinates of each spectral line emitted by the calibration lamp based on the image of the spectrum of the calibration lamp emitted in step 4.1; Step 4.2: Query the NIST database to find the wavelength of the calibration lamp's output spectrum line corresponding to the position coordinates of each calibration lamp's output spectrum line corresponding to the image of the calibration lamp's output spectrum collected in step 4.1; Step 4.3, select 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 the synchronous calibration spectrum lines; the synchronous calibration spectrum lines are: the calibration lamp auxiliary calibration spectrum lines in step 3, 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 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. Input the position coordinates of the fluorescence spectrum line of the ion to be measured into the final calibration polynomial to obtain the fluorescence wavelength measurement value of the ion to be measured for each fluorescence spectrum line of the ion to be measured.

8. A high-precision calibration method for ion fluorescence wavelength measurement according to claim 7, characterized in that: The reflector (4) described in step 2.1 and step 4.1 is moved back and forth multiple times between the first lens group (3) and the filter slit (7), and the EMCCD camera (11) correspondingly collects pictures of the ion fluorescence spectrum line and the picture of the calibration lamp output light spectrum 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 ion fluorescence spectrum image is the image of the noble gas ion fluorescence spectrum; the ion fluorescence spectrum line is the noble gas ion fluorescence spectrum line; For step 4.1, the image of the ion fluorescence spectrum is the image of the fluorescence spectrum of the ion to be measured; and the ion fluorescence spectrum line is the fluorescence spectrum line of the ion to be measured.

9. A high-precision calibration method for ion fluorescence wavelength measurement according to claim 1, 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 measurements 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 measurement value .

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