CN109520941A - The receptance function bearing calibration of online spectrum measurement instruments - Google Patents

The receptance function bearing calibration of online spectrum measurement instruments Download PDF

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CN109520941A
CN109520941A CN201811381410.XA CN201811381410A CN109520941A CN 109520941 A CN109520941 A CN 109520941A CN 201811381410 A CN201811381410 A CN 201811381410A CN 109520941 A CN109520941 A CN 109520941A
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spectral
absorption
correction
spectrum
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CN109520941B (en
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杜振辉
王晓雨
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Tianjin University
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    • G01MEASURING; TESTING
    • G01NINVESTIGATING OR ANALYSING MATERIALS BY DETERMINING THEIR CHEMICAL OR PHYSICAL PROPERTIES
    • G01N21/00Investigating or analysing materials by the use of optical means, i.e. using sub-millimetre waves, infrared, visible or ultraviolet light
    • G01N21/17Systems in which incident light is modified in accordance with the properties of the material investigated
    • G01N21/25Colour; Spectral properties, i.e. comparison of effect of material on the light at two or more different wavelengths or wavelength bands
    • G01N21/27Colour; Spectral properties, i.e. comparison of effect of material on the light at two or more different wavelengths or wavelength bands using photo-electric detection ; circuits for computing concentration
    • G01N21/274Calibration, base line adjustment, drift correction

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Abstract

本公开提供一种在线光谱测量仪器的响应函数校正方法。利用标准物质在数据库中标准光谱线形数据,对实验测量中获得的混合物质光谱信号中的标准物质的线形进行对比,从而实现利用小分子物质光谱线形的多维信息,对混合物质信号整体线形以及特殊形状光谱进行校正,从而实现对光谱测量仪器响应函数的校正,无需额外设备且误差小,适应性强。

The disclosure provides a response function calibration method of an online spectrum measuring instrument. Use the standard spectral line shape data of the standard substance in the database to compare the line shape of the standard substance in the spectral signal of the mixed substance obtained in the experimental measurement, so as to realize the multidimensional information of the spectral line shape of the small molecule substance, and analyze the overall line shape of the mixed substance signal and the special The shape spectrum is corrected, so as to realize the correction of the response function of the spectrum measuring instrument, no additional equipment is required, the error is small, and the adaptability is strong.

Description

The receptance function bearing calibration of online spectrum measurement instruments
Technical field
This disclosure relates to spectral measurement analysis technical field more particularly to a kind of receptance function of online spectrum measurement instruments Bearing calibration.
Background technique
Spectrum measurement instruments be it is a kind of can analyze light to obtain the common measuring device of spectral information, be now widely used in Various fields, such as gas detection, biotechnology, laser technology field.But due to spectrum measurement instruments or the response letter of system The factors such as non-linear of the noises of several power swing, environment or instruments and system with input signal, detector and signal path It is closely related, so as to cause spectral signal there are baseline drift and the fluctuation of amplitude or distortion, cause to detection accuracy and The influence of sensitivity etc..Thus it is guaranteed that and improve the detection accuracy and sensitivity of spectrum measurement instruments or system, need pair Its receptance function is corrected.But due to the receptance function of spectrum measurement instruments cannot directly be obtained and school only, Utilize the correction realized to the linear correction of measure spectrum to the receptance function of spectrum measurement instruments.
Present most bearing calibration needs to be arranged some empirical parameters, and this reduces correction side to a certain extent The generality and adaptability of method, and be unable in correction signal influence spectrum bring due to the non-linear of detector itself, it is difficult To meet to the high-precision demand of spectrum.For example, Fast Fourier Transform (FFT) method needs artificial determining bound, and spend a large amount of Time calculated.Under many real-time applications, it is difficult to handle original spectrum one by one in face of a large amount of data. Common polynomial fitting assumes that baseline can be approximated to lower order polynomial expressions form, goes to intend with a suitable multinomial Data are closed, gives up any point for being greater than a specific criteria difference in matched curve, iterates to remaining point, until not having There are data point needs to be rejected, and this method effect in the case where low signal-to-noise ratio or low signal background ratio is poor;In addition, very In more application processes, the spectral line of spectrum is rendered as various shapes.The method of simple fitting of a polynomial is not able to satisfy special spectrum Baseline fitting requirement.The automatic Iterative method of moving average is in the case where multimodal or overlap peak, and effect not smooth enough to baseline correction Fruit is not fine;ALS method and air PLS method are all based on the smooth baseline correction of Whittaker, baseline correction effect compared with It is good, but parameter optimization is required, and adjusting optimized parameter is the process for needing experience;And traditional Rubber- If spectrum is divided into stem portion by band method, the minimum point of each part is considered as the position of baseline, then by with linearly Interpolation or spline interpolation combine these points to complete the baseline of estimation, and this method needs artificial adjusting segmentation width, corrects result Quality to a certain extent depend on operator experience.
And existing patent and paper have and are much referred to different spectral correction methods.For example, Taiwan super-micro optical Hong Jianxiang of company et al. (108318137 A of CN) establishes stray light data bank using the response of more narrow frequency spectrographic pulse, with It is established afterwards using the data in data bank and repairs the spectrum that formula removes amendment spectroradio standard light, to obtain measure spectrum number According to generate correction coefficient formula.Although this method effectively, needs to establish database, therefore heavy workload and need by It is gradually perfect, it is not used to online real-time measurement and application range receives the limitation of database.Hangzhou distant place photoelectric information is public The advanced spectroscope function that Pan Jiangen et al. (1021559971 A of CN) calculates spectral instrument using photoradiometer is taken charge of, the letter is utilized Number can be modified spectral instrument measurement result.This method can effectively improve that precision, speed are fast, design is simple and user Just, but it is only limitted to the calibration spectrum measurement of the free wave band of shortwave, application range limitation is big.The auspicious environmental science and technology company of Shenzhen Kapp Ou Yangbin et al. (107607144 A of CN) obtains functional relation using aiding sensors and carries out school to the baseline drift of sensor Just.This method is only capable of the influence of baseline drift in removal measurement result and needs additional aiding sensors during processing It assists.Cyrillic Bo Dibu gas of university, Bordeaux et al. (107076664 A of CN) in multiple absorption spectrums using absorbing The interval spectral coverage for the position that amount is zero determines baseline correction curve.This method uses signal self-correcting, is only capable of preferably removing width Baseline problem caused by the apparent fluctuation of value.Therefore in the prior art, there are no can handle spectral signal simultaneously in real time online Middle noise, baseline drift and detector or signal path cause the bearing calibration of nonlinear influence.
Disclosure
(1) technical problems to be solved
Based on above-mentioned technical problem, the disclosure provides a kind of receptance function bearing calibration of online spectrum measurement instruments, real Now to the correction of the receptance function of spectrum measurement instruments, spectrum can not be handled simultaneously in real time online in the prior art to alleviate The technical issues of noise, baseline drift and detector or signal path cause nonlinear influence in signal.
(2) technical solution
The disclosure provides a kind of receptance function bearing calibration of online spectrum measurement instruments, by adding in measured matter Standard substance after screening realizes the response letter of spectrum measurement instruments using the correction linear to measure spectrum Plays substance Several correction, comprising: step A: using photodetector acquisition absorption signal and background signal, and make in two groups of spectral signals It include one section of signal segment without laser emitting;Wherein, in the absorption signal comprising sample to be tested spectral signal and with this The spectral signal for the standard substance that sample to be tested does not chemically react;Step B: using in the absorption signal and the background signal Signal segment and photodetector without laser emitting eliminate environmental background light without the output signal under laser input state Fluctuate the influence to spectroscopic data;Step C: being respectively weighted fitting to step B treated absorption signal and background signal, And the optical stripe in absorption signal is eliminated using the regression criterion in background signal;Step D: the standard substance acquired is utilized Spectral signal is matched with the spectral information in database, and to step C, treated that absorption signal is corrected, and is corrected The spectral signal of sample to be tested afterwards.
In some embodiments of the present disclosure, the step A includes: step A1: known concentration being added in sample to be tested Standard substance;Wherein, the concentration of the standard substance, so that its feature peak amplitude is less than or equal to the amplitude of sample to be tested It is quasi-;Step A2: it is mixed with the spectral signal of the sample to be tested of standard substance using photodetector acquisition, and utilizes identical system Nitrogen data of the parameter acquisition without absorption of uniting are as background signal;It wherein, include laser tuning in two groups of spectral signals Current threshold output signal below;And step A3: multicycle signal is used to the two groups of spectral signals acquired in step A2 Average method is smoothed.
In some embodiments of the present disclosure, in the step A1: the standard substance contains in tested absorption bands Characteristic peak that is independent and not interfered mutually with measured matter, and have detailed spectrum parameter in the database.
In some embodiments of the present disclosure, the database includes: HITRAN database, PNNL database or NIST number According to library.
In some embodiments of the present disclosure, the step B includes: step B1: determining two groups of spectrum letters on a timeline Number start position, and be aligned two groups of spectral signals on a timeline on the basis of the start position of absorption signal;Step B2: it adopts Collect output signal of the photodetector under no laser input state and calculates signal averaging;Step B3: background signal is calculated With absorption signal laser tuning current threshold output signal below average value;Step B4: step B3 is resulting flat Mean value makes the difference with the resulting average value of step B2 respectively, and using respective difference as offset, moves background signal and suction respectively Position of the collection of letters number on y direction, makes background signal and absorption signal and photodetector under no laser input state The aligned in position of output signal.
In some embodiments of the present disclosure, the step C includes: step C1: to background signal entire data segment into Row weight is 1 fitting;Step C2: the fitting that weight is 0, nothing are carried out to the data segment in absorption signal containing characteristic information The data segment of characteristic information carries out the fitting that weight is 1;Step C3: the regression criterion after step C1 and step C2 fitting is carried out Comparison matching, so that mutually be overlapped with the regression criterion of background signal without the corresponding regression criterion of characteristic information data section in absorption signal It closes;Step C4: the regression criterion of absorption signal and background signal is made the difference, and removes the influence of optical stripe in absorption signal.
In some embodiments of the present disclosure, in the step D: utilize following updating formula, to step C treated inhale The collection of letters number carries out a baseline correction:
I′0(v)=WI0(v)+Q(v)
Wherein, I '0(v) indicate that the spectrum after baseline correction is linear, second order polynomial fitting are as follows: I '0(v)=c+bv+ av2, I0(v) indicate that the spectrum before baseline correction is linear, second order polynomial fitting are as follows: I0(v)=m+nv+tv2,For The gamma correction factor, For deviation constant matrix.
In some embodiments of the present disclosure, the step D includes: step D1: setting W initial value is the initial square of 1, Q (v) Battle array value is all 0;Step D2: the spectral signal and number of the standard substance that Beer-Lambert law acquires photodetector are utilized Linear matching is carried out according to the spectral signal in library, until the variance yields of the two is minimum;Step D3: when acquisition variance yields minimum The gamma correction factor W and deviation constant matrix Q (v).Step D4: minimum two is carried out to deviation constant matrix Q (v) using following formula Multiplication iteration acquires deviation constant Q:
N=Σ (Qi-Qj)2
Wherein, when N obtains minimum value, the spectral signal for the standard substance that deviation constant Q acquires photodetector And the linear deviation of the spectral signal in database is minimum;
Step D5: gamma correction factor W and deviation constant Q are brought into updating formula, and using updating formula to light Spectrum signal is corrected.
In some embodiments of the present disclosure, the step D2 includes: step D2a: obtaining absorption signal Plays substance Spectrum it is linear;Step D2b: the database shape difference linear with the spectrum of absorption signal Plays substance is calculated;Step D2c: The variance of the shape difference obtained in step D2b is calculated, and judges whether variance yields is minimum at this time, if variance is minimum, carries out step Otherwise D3 carries out step D2d;Step D2d: updating the value of gamma correction factor W, is got the bid using updating formula to absorption signal The linear carry out baseline correction of the spectrum of quasi- substance, and return step D2b.
In some embodiments of the present disclosure, in which: the receptance function bearing calibration institute of the online spectrum measurement instruments Applicable spectrum includes: absorption spectrum, emission spectrum, molecular spectrum, atom spectrum;The response of the online spectrum measurement instruments The project that function correction method can correct includes: the non-linear, dry of baseline drift, channel existing for spectral signal and detector It disturbs and noise.
(3) beneficial effect
It can be seen from the above technical proposal that the receptance function bearing calibration for the online spectrum measurement instruments that the disclosure provides It one of has the advantages that or in which a part:
(1) disclosure realizes the correction to spectrum measurement instruments receptance function by the correction linear to measure spectrum, This bearing calibration is not necessarily to extras and error is small, and linear correction can be carried out to special shape spectrum, adaptable;
(2) the receptance function bearing calibration for the online spectrum measurement instruments that the disclosure provides directly utilizes standard substance in number Linear according to the linear standard substance in the compounding substances spectral signal that obtains in experiment measurement of library Plays spectrum carries out pair Than amendment, to realize the school using the linear multidimensional information of the spectrum of small-molecule substance to compounding substances signal integral linear Just, to remove the non-linear and baseline drift in signal, the total regression to the entire signal path including spectrum baseline is realized It corrects, reaches correction while realizing multiple measurement parameters using correction course of a standard substance;
(3) the receptance function bearing calibration for the online spectrum measurement instruments that the disclosure provides is simple and convenient for operation, effective, There is wide applicability in the fields of measurement such as molecular spectrum measurement and content of material.
Detailed description of the invention
Fig. 1 is the step flow chart of the receptance function bearing calibration for the online spectrum measurement instruments that the disclosure provides.
Fig. 2 is spectroscopic data correcting process in the receptance function bearing calibration for the online spectrum measurement instruments that the disclosure provides Figure.
Fig. 3 is the direct absorption spectrum measuring system schematic diagram based on TLAS technology.
Fig. 4 is the initial data schematic diagram of photodetector acquisition.
Fig. 5 is the weighted fitting result and residual error comparison diagram of background signal and absorption signal.
Fig. 6 be using the disclosure provide line spectrum measurement instruments receptance function bearing calibration correction after baseline with Baseline comparison diagram before correction.
Fig. 7 is the comparison diagram and correcting value before and after spectrum correction.
Specific embodiment
The receptance function bearing calibration for the online spectrum measurement instruments that the disclosure provides directly utilizes standard substance in data Plays spectrum linear the linear of standard substance in the compounding substances spectral signal obtained in experiment measurement in library compares Amendment is not necessarily to extras and error is small to realize the correction to spectrum measurement instruments receptance function, adaptable.
For the purposes, technical schemes and advantages of the disclosure are more clearly understood, below in conjunction with specific embodiment, and reference The disclosure is further described in attached drawing.
The disclosure provides a kind of receptance function bearing calibration of online spectrum measurement instruments, by adding in measured matter Standard substance after screening realizes the response letter of spectrum measurement instruments using the correction linear to measure spectrum Plays substance Several corrections, as shown in Figure 1 to Figure 2, comprising:
Step A: using photodetector acquisition absorption signal and background signal, and make include in two groups of spectral signals One section of signal segment without laser emitting;
Wherein, in the absorption signal comprising sample to be tested spectral signal and do not chemically reacted with the sample to be tested Standard substance spectral signal;
Step B: using in the absorption signal and the background signal without laser emitting signal segment and photodetector without Output signal under laser input state eliminates influence of the fluctuation of environmental background light to spectroscopic data;
Step C: fitting is respectively weighted to step B treated absorption signal and background signal, and is believed using background Regression criterion in number eliminates the optical stripe in absorption signal;
Step D: it is matched using the spectral signal of the standard substance of acquisition with the spectral information in database, to step Treated that absorption signal is corrected by C, the spectral signal of the sample to be tested after being corrected.
In some embodiments of the present disclosure, step A includes:
Step A1: the standard substance of known concentration is added in sample to be tested;
Wherein, the concentration of the standard substance, so that its feature peak amplitude is less than or equal to subject to the amplitude of sample to be tested;
Step A2: it is mixed with the spectral signal of the sample to be tested of standard substance using photodetector acquisition, and utilizes phase Same nitrogen data of the system parameter acquisition without absorption are as background signal;
It wherein, include laser tuning current threshold output signal below in two groups of spectral signals;
Step A3: the two groups of spectral signals acquired in step A2 are smoothly located using the method for multicycle signal averaging Reason.
In some embodiments of the present disclosure, step A1: standard substance in tested absorption bands containing it is independent and not with The characteristic peak that measured matter mutually interferes, and have detailed spectrum parameter in the database.
In some embodiments of the present disclosure, database includes: HITRAN database, PNNL database or NIST database.
In some embodiments of the present disclosure, as shown in " signal alignment " part in Fig. 2, step B includes:
Step B1: the start position (s and r) of two groups of spectral signals is determined, and on a timeline with the starting point of absorption signal Two groups of spectral signals are aligned on the basis of the r of position on a timeline;
Step B2: in acquisition longer period of time, output signal and meter of the photodetector under no laser input state Signal averaging is calculated, d is denoted as;
Step B3: background signal and absorption signal being averaged in laser tuning current threshold output signal below are calculated Value, is denoted as f and e respectively;
Step B4: the resulting average value f and e of step B3 is made the difference with the resulting average value d of step B2 respectively, and with respective Difference be offset, move the position of background signal and absorption signal on y direction respectively, make background signal and absorption The aligned in position of the output signal of signal and photodetector under no laser input state.
In some embodiments of the present disclosure, step C includes:
Step C1: the fitting that weight is 1 is carried out in entire data segment to background signal;
Step C2: carrying out the fitting that weight is 0 to the data segment in absorption signal containing characteristic information, no characteristic information Data segment carries out the fitting that weight is 1;
Step C3: the regression criterion after step C1 and step C2 fitting is compared into matching, so that nothing in absorption signal The regression criterion of the corresponding regression criterion of characteristic information data section and background signal coincides;
Step C4: the regression criterion of absorption signal and background signal is made the difference, and removes the shadow of optical stripe in absorption signal It rings.
In some embodiments of the present disclosure, step D: following updating formula is utilized, to step C treated absorption signal Carry out baseline correction:
I′0(v)=WI0(v)+Q(v)
Wherein, I '0(v) indicate that the spectrum after baseline correction is linear, second order polynomial fitting are as follows: I '0(v)=c+bv+ av2, It(v) indicate that the spectrum before baseline correction is linear, second order polynomial fitting are as follows: I0(v)=m+nv+tv2,For The gamma correction factor, For deviation constant matrix.
In some embodiments of the present disclosure, step D includes:
Step D1: setting W initial value is that 1, Q (v) initial matrix value is all 0;
Step D2: the spectral signal and data of the standard substance that Beer-Lambert law acquires photodetector are utilized Spectral signal in library carries out linear matching, until the variance yields of the two is minimum;
Step D3: the gamma correction factor W and deviation constant matrix Q (v) when variance yields minimum are obtained.
Step D4: least square method iteration is carried out to deviation constant matrix Q (v) using following formula and acquires deviation constant Q:
N=Σ (Qi-Qj)2
Wherein, when N obtains minimum value, the spectral signal for the standard substance that deviation constant Q acquires photodetector And the linear deviation of the spectral signal in database is minimum;
Step D5: gamma correction factor W and deviation constant Q are brought into updating formula, and using updating formula to light Spectrum signal is corrected.
In some embodiments of the present disclosure, as shown in " extension Internal standard correction methods " part in Fig. 2, step D2 includes:
Step D2a: the spectrum for obtaining absorption signal Plays substance is linear;
Step D2b: the database shape difference linear with the spectrum of absorption signal Plays substance is calculated;
Step D2c: calculating the variance of the shape difference obtained in step D2b, and judges whether variance yields is minimum at this time, if side It is poor minimum, step D3 is carried out, step D2d is otherwise carried out;
Step D2d: the value of gamma correction factor W is updated, using updating formula to the light of absorption signal Plays substance Spectral line shape carries out baseline correction, and return step D2b.
In some embodiments of the present disclosure, in which: the receptance function correction for the online spectrum measurement instruments that the disclosure provides The spectrum that method is applicable in includes: absorption spectrum, emission spectrum, molecular spectrum, atom spectrum;The disclosure provide in line spectrum The project that the receptance function bearing calibration of measuring instrument can correct includes: baseline drift, channel existing for spectral signal and inspection Survey the non-linear of device, interference and noise.
Below with a specific embodiment, the receptance function bearing calibration for the online spectrum measurement instruments that the disclosure provides is verified Validity:
As shown in figure 3, being based on tunable laser absorption spectrum (Tunable Laser AbsorptionSpectroscopy, TLAS) technology constructs spectral measurement system, and SG is signal generator in Fig. 3, and LDC is sharp CD-ROM driver, DFB-ICL are distributed Feedback interband cascade lasers, and PD is photodetector, and DAQ is data collecting card, PC Acetonitrile (CH is selected according to the existence conditions that experiment has for computer3CN it) is used as measured matter, and is swashed in Binding experiment system The scanning range of light device determines that detection wave band is 3037.5-3043cm-1
Step 1: screening criteria substance: the requirement of combination technology scheme, the standard substance finally chosen are methane.
Step 2: preparing sample to be tested: for the validity for verifying bearing calibration, being mixed with the calibrating gas of known concentration Close the proportion of gaseous sample.Experiment utilizes 10.2ppm methane (CH4) as a kind of standard substance addition 160.8ppm CH3CN sample In product.
Step 3: acquisition data: by proportioned mixed gas sample under conditions of normal temperature and pressure (23.6 DEG C, 1atm) It is passed through in the gas cell of 10.24455m light path, and absorbs information containing mixed gas using what capture card acquired 20 periods Signal It.Then, the pure nitrogen gas for being passed through enough time blows mixed gas, and is believed using identical sampling parameter acquisition nitrogen Number as background signal such as.Collected original signal is as shown in figure 4, without absorption peak be background signal I0, contain absorption peak Be mixed gas absorption signal It
Step 4: noise reduction process: two groups of signals will be obtained in step 3 and carry out monocycle signal extraction respectively, then to 20 The cycle data progress period is average, to realize signal smoothing.
Step 5: signal alignment: as shown in " signal alignment " part in Fig. 2, determining that two groups of signals are each on a timeline first From initial point position (s and r), and be aligned two signals on a timeline on the basis of the start position r of absorption signal.Then, Background signal I is obtained respectively0With absorption signal ItWhen below laser tuning current threshold (in 0.002 second), output signal Average value be respectively f and e.Then, the photodetector in one hour is acquired under the natural working condition that no laser inputs Output signal and calculate signal averaging be d.Later, background signal I is utilized0With absorption signal ItResulting average value f, e points The average value d not obtained with photodetector makes the difference, and using respective difference as offset, moves background signal I respectively0And suction Collection of letters ItPosition on y direction, so that background signal I0With absorption signal ItIt is inputted with photodetector in no laser Natural working condition under output signal aligned in position, to eliminate the influence of background light beats.
Step 6: weighted fitting: to by step 5 treated background signal I0With absorption signal ItIt is respectively weighted quasi- It closes.To background signal I0After entire data segment carries out the fitting that weight is 1, the available complete light in regression criterion Striped and noise are learned, as shown in Fig. 5 (a), due to absorption signal ItIt is middle to there is absorption information, therefore using sectionally weighting fitting Method will be set as 1 without the position weight for absorbing information, other positions 0, to curve matching be come out, such as Fig. 5 (b) institute Show, then, by background signal I0With absorption signal ItRegression criterion compare, it can be found that background signal from Fig. 5 (c) I0With absorption signal ItOptical stripe can be well matched with, so as to utilize background signal I0In regression criterion disappear Except absorption signal ItMiddle optical stripe.
Step 7: baseline correction: will be by the absorption signal I of step 6 removal optical stripetCarry out baseline correction, processing stream Journey sets 1 for gamma correction factor W first, utilizes the mixed of experiment acquisition as shown in " extension Internal standard correction methods " part in Fig. 2 Close gas absorption signal Plays substance C H4Absorption lineshape matched with the linear of CH4 in HITRAN database.Correction is calculated Method is iterated by least square method, when the value of W is adjusted to the two variance minimum, acquires the final gamma correction factor W and deviation constant matrix Q (v), since Q (v) is an array, it contain between two curves with all independent variable v phases Corresponding offset.Therefore, the smallest offset of variance that can make two curves is obtained by the iteration of least square method Constant Q, i.e., when quadratic sum N is minimum, corresponding QiThe deviation of two curves can be made minimum, Q=Qi, after corrected For baseline as shown in fig. 6, top curve is before correcting, lower curve is after correcting.Finally, utilizing the resulting gamma correction factor W and deviation constant Q combines the signal expression before correction, the signal after correction can be obtained, as shown in Figure 7 the mixing of correction front and back The absorption spectrum of gas has obvious gap, and can intuitively find out the value of correcting value.
In conclusion the receptance function bearing calibration for the online spectrum measurement instruments that the disclosure provides can remove in signal Non-linear and baseline drift, realization the total regression of the entire signal path including spectrum baseline is corrected, reach and utilize one Correction course of a standard substance corrects while realizing multiple measurement parameters, and final realize responds letter to spectrum measurement instruments Several corrections.
It should also be noted that, the direction term mentioned in embodiment, for example, "upper", "lower", "front", "rear", " left side ", " right side " etc. is only the direction with reference to attached drawing, not is used to limit the protection scope of the disclosure.Through attached drawing, identical element by Same or similar appended drawing reference indicates.When may cause understanding of this disclosure and cause to obscure, conventional structure will be omitted Or construction.
And the shape and size of each component do not reflect actual size and ratio in figure, and only illustrate the embodiment of the present disclosure Content.In addition, in the claims, any reference symbol between parentheses should not be configured to the limit to claim System.
Similarly, it should be understood that in order to simplify the disclosure and help to understand one or more of each open aspect, Above in the description of the exemplary embodiment of the disclosure, each feature of the disclosure is grouped together into single implementation sometimes In example, figure or descriptions thereof.However, the disclosed method should not be interpreted as reflecting the following intention: i.e. required to protect The disclosure of shield requires features more more than feature expressly recited in each claim.More precisely, such as front Claims reflect as, open aspect is all features less than single embodiment disclosed above.Therefore, Thus the claims for following specific embodiment are expressly incorporated in the specific embodiment, wherein each claim itself All as the separate embodiments of the disclosure.
Particular embodiments described above has carried out further in detail the purpose of the disclosure, technical scheme and beneficial effects Describe in detail it is bright, it is all it should be understood that be not limited to the disclosure the foregoing is merely the specific embodiment of the disclosure Within the spirit and principle of the disclosure, any modification, equivalent substitution, improvement and etc. done should be included in the guarantor of the disclosure Within the scope of shield.

Claims (10)

1.一种在线光谱测量仪器的响应函数校正方法,通过在被测物质中添加筛选后的标准物质,利用对测量光谱中标准物质线形的校正,实现光谱测量仪器的响应函数的校正,包括:1. A method for correcting the response function of an online spectral measuring instrument, by adding a screened standard substance in the measured substance, utilizing the correction of the linear shape of the standard substance in the measured spectrum, to realize the correction of the response function of the spectral measuring instrument, including: 步骤A:利用光电探测器采集吸收信号和背景信号,且使该两组光谱信号中均包括一段无激光出射的信号段;Step A: using a photodetector to collect the absorption signal and the background signal, and making the two sets of spectral signals include a signal segment without laser emission; 其中,该吸收信号中包含待测样品的光谱信号以及与该待测样品不发生化学反应的标准物质的光谱信号;Wherein, the absorption signal includes the spectral signal of the sample to be tested and the spectral signal of a standard substance that does not chemically react with the sample to be tested; 步骤B:利用该吸收信号和该背景信号中无激光出射的信号段,以及光电探测器无激光输入状态下的输出信号,消除环境背景光的波动对光谱数据的影响;Step B: using the absorption signal and the signal segment of the background signal without laser emission, and the output signal of the photodetector in the state of no laser input, to eliminate the influence of the fluctuation of the ambient background light on the spectral data; 步骤C:对步骤B处理后的吸收信号和背景信号各自进行加权拟合,并利用背景信号中的拟合残差消除吸收信号中的光学条纹;Step C: performing weighted fitting on the absorption signal and the background signal processed in step B, and using the fitting residual in the background signal to eliminate the optical fringes in the absorption signal; 步骤D:利用采集的标准物质的光谱信号与数据库中的光谱信息进行匹配,对步骤C处理后的吸收信号进行校正,得到校正后的待测样品的光谱信号。Step D: matching the spectral signal of the collected standard substance with the spectral information in the database, correcting the processed absorption signal in step C, and obtaining the corrected spectral signal of the sample to be tested. 2.根据权利要求1所述的在线光谱测量仪器的响应函数校正方法,所述步骤A包括:2. the response function correction method of online spectrum measuring instrument according to claim 1, described step A comprises: 步骤A1:在待测样品中加入已知浓度的标准物质;Step A1: Add a standard substance of known concentration to the sample to be tested; 其中,所述标准物质的浓度,以使其特征峰幅值低于或等于待测样品的幅值为准;Wherein, the concentration of the standard substance is such that its characteristic peak amplitude is lower than or equal to the amplitude of the sample to be tested; 步骤A2:利用光电探测器采集混合有标准物质的待测样品的光谱信号,并利用相同的系统参数采集无吸收的氮气数据作为背景信号;Step A2: Use the photodetector to collect the spectral signal of the sample to be tested mixed with the standard substance, and use the same system parameters to collect non-absorbing nitrogen data as the background signal; 其中,该两组光谱信号中均包含激光器调谐电流阈值以下的输出信号;Wherein, the two groups of spectral signals include output signals below the laser tuning current threshold; 步骤A3:对步骤A2中采集的两组光谱信号采用多周期信号平均的方法进行平滑处理。Step A3: smoothing the two groups of spectral signals collected in step A2 by means of multi-period signal averaging. 3.根据权利要求2所述的在线光谱测量仪器的响应函数校正方法,所述步骤A1中:所述标准物质在被测吸收波段内含有独立且不与被测物质相干扰的特征峰,并在数据库中有详细的光谱参数。3. the response function correction method of online spectrometer measuring instrument according to claim 2, in described step A1: described standard substance contains the characteristic peak that is independent and does not interfere with measured substance in the measured absorption band, and There are detailed spectral parameters in the database. 4.根据权利要求3所述的在线光谱测量仪器的响应函数校正方法,所述数据库包括:HITRAN数据库、PNNL数据库或NIST数据库。4. The method for calibrating the response function of an online spectral measuring instrument according to claim 3, said database comprising: a HITRAN database, a PNNL database or a NIST database. 5.根据权利要求1所述的在线光谱测量仪器的响应函数校正方法,所述步骤B包括:5. the response function correction method of online spectrum measuring instrument according to claim 1, described step B comprises: 步骤B1:在时间轴上确定两组光谱信号的起点位置,并以吸收信号的起点位置为基准在时间轴上对齐两组光谱信号;Step B1: Determine the starting positions of the two groups of spectral signals on the time axis, and align the two groups of spectral signals on the time axis based on the starting positions of the absorption signals; 步骤B2:采集光电探测器在无激光输入状态下的输出信号并计算信号平均值;Step B2: Collect the output signal of the photoelectric detector in the state of no laser input and calculate the average value of the signal; 步骤B3:计算背景信号和吸收信号在激光器调谐电流阈值以下的输出信号的平均值;Step B3: Calculate the average value of the output signal of the background signal and the absorption signal below the laser tuning current threshold; 步骤B4:将步骤B3所得的平均值分别与步骤B2所得的平均值做差,并以各自的差值为偏移量,分别移动背景信号和吸收信号在纵轴方向上的位置,使背景信号和吸收信号与光电探测器在无激光输入状态下的输出信号的位置对齐。Step B4: Make the difference between the average value obtained in step B3 and the average value obtained in step B2, and use the respective differences as offsets to move the positions of the background signal and the absorption signal in the vertical axis direction, so that the background signal and the absorption signal are aligned with the position of the output signal of the photodetector in the state of no laser input. 6.根据权利要求1所述的在线光谱测量仪器的响应函数校正方法,所述步骤C包括:6. the response function correction method of online spectral measuring instrument according to claim 1, described step C comprises: 步骤C1:对背景信号在整个数据段进行权重均为1的拟合;Step C1: Fitting the background signal with a weight of 1 in the entire data segment; 步骤C2:对吸收信号中含有特征信息的数据段进行权重为0的拟合,无特征信息的数据段进行权重为1的拟合;Step C2: The weight of the data segment containing the characteristic information in the absorption signal is fitted with a weight of 0, and the weight of the data segment without special information is 1; 步骤C3:将步骤C1和步骤C2拟合后的拟合残差进行对比匹配,使得吸收信号中无特征信息数据段对应的拟合残差与背景信号的拟合残差相重合;Step C3: comparing and matching the fitting residuals after fitting in step C1 and step C2, so that the fitting residual corresponding to the data segment without feature information in the absorption signal coincides with the fitting residual of the background signal; 步骤C4:将吸收信号与背景信号的拟合残差做差,去除吸收信号中光学条纹的影响。Step C4: The difference between the fitting signal with the background signal is different to remove the effect of optical stripes in the absorption signal. 7.根据权利要求3所述的在线光谱测量仪器的响应函数校正方法,所述步骤D中:利用如下校正公式,对步骤C处理后的吸收信号进行基线校正:7. The method for correcting the response function of the online spectral measuring instrument according to claim 3, in the step D: use the following correction formula to perform baseline correction on the absorption signal processed in the step C: I′0(v)=WI0(v)+Q(v)I′ 0 (v)=WI 0 (v)+Q(v) 其中,I′0(v)表示基线校正后的光谱线形,其二阶拟合多项式为:I′0(v)=c+bv+av2,I0(v)表示基线校正前的光谱线形,其二阶拟合多项式为:I0(v)=m+nv+tv2为非线性校正因子, 为偏移常数矩阵。Among them, I′ 0 (v) represents the spectral line shape after baseline correction, and its second-order fitting polynomial is: I′ 0 (v)=c+bv+av 2 , and I 0 (v) represents the spectral line shape before baseline correction , its second-order fitting polynomial is: I 0 (v)=m+nv+tv 2 , is the nonlinear correction factor, is the offset constant matrix. 8.根据权利要求7所述的在线光谱测量仪器的响应函数校正方法,所述步骤D包括:8. The response function correction method of the online spectrometer measurement instrument according to claim 7, the step d includes: 步骤D1:设置W初始值为1,Q(v)初始矩阵值全为0;Step D1: Set the initial value of W to 1, and the initial matrix values of Q(v) are all 0; 步骤D2:利用Beer-Lambert定律对光电探测器采集的标准物质的光谱信号与数据库中的光谱信号进行线形匹配,直至其二者的方差值最小;Step D2: use the Beer-Lambert law to linearly match the spectral signal of the standard substance collected by the photodetector with the spectral signal in the database until the variance between the two is the smallest; 步骤D3:获取方差值最小时的非线性校正因子W和偏移常数矩阵Q(v)。Step D3: The non -linear correction factor W and offset constant matrix Q (V) of the minimum of obtaining the variance value. 步骤D4:利用下式对偏移常数矩阵Q(v)进行最小二乘法迭代求得偏移常数Q:Step D4: Use the below formula to offset constant matrix Q (v) for minimum secondary multiplication iteration to obtain offset constant Q: N=∑(Qi-Qj)2 N=∑(Q i -Q j ) 2 其中,当N取得最小值时,偏移常数Q使得光电探测器采集的标准物质的光谱信号与数据库中的光谱信号的线形偏差最小;Wherein, when N obtains the minimum value, the offset constant Q makes the linear deviation of the spectral signal of the standard substance collected by the photodetector and the spectral signal in the database the smallest; 步骤D5:将非线性校正因子W和偏移常数Q带入校正公式中,并利用校正公式对光谱信号进行校正。Step D5: Bring non -linear correction factor W and offset constant Q into the formal formula, and use the correction formula to correct the spectral signal. 9.根据权利要求8所述的在线光谱测量仪器的响应函数校正方法,所述步骤D2包括:9. The response function correction method of the online spectrometer measurement instrument according to claim 8, the step d2 includes: 步骤D2a:获取吸收信号中标准物质的光谱线形;Step D2A: Get the spectral linear of the standard substance in the absorption signal; 步骤D2b:计算数据库与吸收信号中标准物质的光谱线形的形差值;Step D2B: Calculate the shape value of the spectral linear of the standard substance in the database and absorption signal; 步骤D2c:计算步骤D2b中获得的形差值的方差,并判断此时方差值是否最小,若方差最小,进行步骤D3,否则进行步骤D2d;Step D2c: Calculate the variance of the shape difference value obtained in step D2b, and judge whether the variance value is the smallest at this time, if the variance is the smallest, go to step D3, otherwise go to step D2d; 步骤D2d:更新非线性校正因子W的值,利用校正公式对吸收信号中标准物质的光谱线形进行基线校正,并返回步骤D2b。Step D2D: Update the value of the nonlinear correction factor W, and use the correction formula to perform the baseline correction of the spectral linear of the standard substance in the absorption signal, and return the step D2B. 10.根据权利要求1至9中任一项所述的在线光谱测量仪器的响应函数校正方法,其中:10. According to the right requirements of the claim 1 to 9, the response function correction method of the instrument of the online spectrum measuring instrument, wherein: 所述在线光谱测量仪器的响应函数校正方法所适用的光谱包括:吸收光谱、发射光谱、分子光谱、原子光谱;The spectrum applied to the response function of the online spectrometer measurement instrument includes: absorbing spectra, launch spectrum, molecular spectrum, atomic spectrum; 所述在线光谱测量仪器的响应函数校正方法所能校正的项目包括:光谱信号存在的基线漂移、通道和检测器的非线性、干扰以及噪声。The items that can be corrected by the response function correction method of an online spectrometer measuring instrument can include: baseline drift, channel and non -linearity, interference, and noise of the existence of spectral signals.
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Cited By (5)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
CN110108694A (en) * 2019-05-17 2019-08-09 广西科技大学 Method for Improving Measurement Accuracy of Raman Spectrometer Wavenumber Migration
CN114384028A (en) * 2021-12-14 2022-04-22 安徽皖仪科技股份有限公司 Peak drift correction method for continuous flow analyzer
CN117270024A (en) * 2023-11-20 2023-12-22 合肥综合性国家科学中心人工智能研究院(安徽省人工智能实验室) Method and device for correcting energy spectrum response function, computer equipment and storage medium
CN118425098A (en) * 2024-07-04 2024-08-02 鞍山天汇科技有限公司 Distributed laser methane detection method and system
CN118566173A (en) * 2024-08-05 2024-08-30 华夏天信传感科技(大连)有限公司 Noise suppression effect inspection method and device

Citations (6)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
JPH0727703A (en) * 1993-07-08 1995-01-31 Hitachi Ltd Quantitative analysis method for multi-component substances
CN1149334A (en) * 1994-05-27 1997-05-07 伊斯特曼化学公司 Raman spectrometry apparatus and method
CN101101338A (en) * 2007-07-10 2008-01-09 廊坊开发区中油油田科技工贸有限责任公司 Exploration method and system for oil and gas
CN102155991A (en) * 2011-03-18 2011-08-17 杭州远方光电信息股份有限公司 Advanced spectrum correcting method
CN205821460U (en) * 2016-08-03 2016-12-21 苏州热工研究院有限公司 A kind of portable reference electrode calibration system being applicable to run mediator depletion
CN106769906A (en) * 2016-12-14 2017-05-31 重庆川仪自动化股份有限公司 Spectrometer data wander compensation method

Patent Citations (6)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
JPH0727703A (en) * 1993-07-08 1995-01-31 Hitachi Ltd Quantitative analysis method for multi-component substances
CN1149334A (en) * 1994-05-27 1997-05-07 伊斯特曼化学公司 Raman spectrometry apparatus and method
CN101101338A (en) * 2007-07-10 2008-01-09 廊坊开发区中油油田科技工贸有限责任公司 Exploration method and system for oil and gas
CN102155991A (en) * 2011-03-18 2011-08-17 杭州远方光电信息股份有限公司 Advanced spectrum correcting method
CN205821460U (en) * 2016-08-03 2016-12-21 苏州热工研究院有限公司 A kind of portable reference electrode calibration system being applicable to run mediator depletion
CN106769906A (en) * 2016-12-14 2017-05-31 重庆川仪自动化股份有限公司 Spectrometer data wander compensation method

Non-Patent Citations (2)

* Cited by examiner, † Cited by third party
Title
NAOKI SAITO等: "Extended internal standard method for quantitative 1H NMR assisted by chromatography (EIC) for analyte overlapping impurity on 1H NMR spectra", 《TALANTA》 *
董学锋等: "基于高斯函数卷积的色散型拉曼光谱仪温度校正", 《分析化学研究报告》 *

Cited By (10)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
CN110108694A (en) * 2019-05-17 2019-08-09 广西科技大学 Method for Improving Measurement Accuracy of Raman Spectrometer Wavenumber Migration
CN110108694B (en) * 2019-05-17 2021-11-02 广西科技大学 Raman Spectrometer Wavenumber Shift Measurement Accuracy Improvement Method
CN114384028A (en) * 2021-12-14 2022-04-22 安徽皖仪科技股份有限公司 Peak drift correction method for continuous flow analyzer
CN114384028B (en) * 2021-12-14 2023-10-24 安徽皖仪科技股份有限公司 Peak drift correction method for continuous flow analyzer
CN117270024A (en) * 2023-11-20 2023-12-22 合肥综合性国家科学中心人工智能研究院(安徽省人工智能实验室) Method and device for correcting energy spectrum response function, computer equipment and storage medium
CN117270024B (en) * 2023-11-20 2024-02-20 合肥综合性国家科学中心人工智能研究院(安徽省人工智能实验室) Method and device for correcting energy spectrum response function, computer equipment and storage medium
CN118425098A (en) * 2024-07-04 2024-08-02 鞍山天汇科技有限公司 Distributed laser methane detection method and system
CN118425098B (en) * 2024-07-04 2024-08-23 鞍山天汇科技有限公司 Distributed laser methane detection method and system
CN118566173A (en) * 2024-08-05 2024-08-30 华夏天信传感科技(大连)有限公司 Noise suppression effect inspection method and device
CN118566173B (en) * 2024-08-05 2024-10-01 华夏天信传感科技(大连)有限公司 Noise suppression effect inspection method and device

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