A method and system for multi-physical quantity measurement of gas breaking the range limit

Abstract

The present application relates to a kind of gas multi-physical quantity measurement method and system that breaks through range limit, utilize signal generator to generate special periodic driving voltage signal, control the output light wavelength periodic special change of laser light source, create multiple artificial peaks outside absorption peak, constitute absorption peak group, set different temperature, pressure, concentration simulation calculates the absorbance of each wavelength of absorption peak group, constitute simulation data group, then obtain the measurement data group of absorbance by actual measurement, square error is obtained by two, the temperature, pressure, concentration of the simulation data group of minimum error is measurement value.The present application can provide multiple absorption peak peak value data for measuring multiple physical quantities by only one absorption line, compared with the double line method of prior art, greatly reduce the measurement workload and system cost, also widen range.

Description

TECHNICAL FIELD

[0001] The present application relates to the field of laser absorption spectroscopy gas measurement, and particularly to a gas multi-physical quantity measurement method and system breaking through the range limit. BACKGROUND

[0002] Laser absorption spectroscopy technology is a method of qualitatively or quantitatively analyzing a to-be-measured component by measuring the absorption spectrum of transmitted light of the to-be-measured component irradiated by light, and plays an important role in the fields of atmospheric environment monitoring, biomedical applications, energy combustion diagnosis, food and pharmaceutical industries, etc.

[0003] When a laser gas sensor is designed by using absorption spectroscopy technology, the concentration of the to-be-measured component is generally inversely calculated by the peak value of the absorbance corresponding to the maximum absorption wavelength. The ratio of the integral absorbance or the peak absorbance of the to-be-measured component at two wavelengths is obtained, the ratio is independent of temperature, and then temperature measurement is realized, which is also called double-line method temperature measurement. Pressure measurement is realized by analyzing the pressure broadening and absorbance change of the absorption line type of the test component.

[0004] Double-line method temperature measurement requires absorbance measurement at two wavelengths, which puts higher requirements on the setting of the detection system and increases the detection workload.

[0005] In addition, the above three kinds of physical quantity measurement methods all depend on the fact that the peak value of the absorbance of the to-be-measured component is within the design range of the sensor, that is, saturation of absorption is not reached, so the range is limited and the range is small. In addition, the range and sensitivity of the laser gas sensor are contradictory, in order to obtain higher detection sensitivity, the range is often reduced, and this contradiction point further limits the range of the measurement system. SUMMARY

[0006] In view of the above-mentioned shortcomings or deficiencies of the prior art, the technical problem to be solved by the present application is to provide a multi-physical quantity measurement method and system with a larger range, which can simultaneously measure the concentration, temperature and pressure of the to-be-measured component.

[0007] To solve the above technical problems, the present application has the following structure:

[0008] The application discloses a gas multi-physical quantity measurement method which breaks through the range limit and sequentially comprises the following steps: S1, determining the wavelengths of multiple artificial absorption peaks according to the maximum absorption wavelength of a to-be-measured component; S2, designing a special periodic driving voltage signal function f(t) of a signal generator to control the periodic special change of output light of a laser light source at the absorption peak and the artificial peak wavelengths; S3, simulating and calculating the absorbance of each absorption peak under different temperature, pressure and concentration values to form a simulated absorbance group; S4, setting a test system, collecting the output light of the laser light source and the transmission light signal of the output light passing through the to-be-measured component by using a data acquisition unit, calculating the absorbance of the to-be-measured component, and finding the absorption peak in the absorbance-time curve; S5, screening effective absorption peaks from all the absorption peaks, and taking the absorbance of the effective absorption peaks as a measurement absorbance group; and S6, comparing each value of the simulated absorbance group in S3 with the measurement absorbance group in S5, and taking the temperature, pressure and concentration corresponding to the simulated absorbance group closest to the measurement value as the measured temperature, pressure and concentration of the to-be-measured component.

[0009] Specifically, step S2 generates a special periodic driving voltage signal f(t) by a signal generator, and sends the signal to a laser controller, so that the laser controller generates a corresponding special periodic driving current signal to make the output light of the laser light source periodically change in shape, and the output light wavelength is positively correlated with the special periodic driving voltage signal.

[0010] Specifically, step S4 comprises the following steps.

[0011] S4.1, the test system comprises a signal generator, a laser controller and a laser light source, and the output light of the laser light source irradiates a sample chamber; and a data acquisition unit collects the transmission light signal passing through the sample chamber.

[0012] S4.2, the sample chamber has two states of not being filled with gas and being filled with the to-be-measured component gas, the data acquisition unit collects the transmission light signals in the two states, and draws two light intensity-time curves.

[0013] S4.3, the absorbance is calculated, and an absorbance-time curve is drawn.

[0014] S4.4, the absorption peak is found in the curve in S4.3.

[0015] Further, in step S5, the absorption peak between the absorbance corresponding to the absorption saturation and the minimum absorbance that can be detected by the system is the effective absorption peak, and the number of effective absorption peaks in one period is greater than or equal to 3, and if the condition is not met, steps S1 to S4 are repeated.

[0016] Specifically, in S6, the method of solving the mean square error of the simulated absorbance group and the measurement absorbance group is used to determine the simulated absorbance group closest to the measurement value.

[0017] Specifically, the formula for calculating absorbance using S3 simulation is: A(ν)=S(T)φ(ν)PCL.

[0018] This invention relates to a gas multi-physical quantity measurement system that breaks through the range limit, comprising a signal generator, a laser controller, a laser source, a sample chamber, a photodetector, and a data acquisition and processing system. The signal generator produces a shaped periodic driving voltage signal and sends it to the laser controller. The laser controller generates a corresponding shaped periodic driving current signal, causing the output wavelength of the laser source to change periodically. The wavelengths of the absorption peaks and artificial absorption peaks of the laser source output light are determined according to the maximum absorption wavelength of the analyte. The photodetector receives the light signal from the laser sweeping across the sample chamber and transmits it to the data acquisition and processing system. The data acquisition and processing system includes a data acquisition unit, a data processing unit, and a data output unit. The transmitted light signal passing through the sample chamber is converted into an electrical signal by a photodetector and transmitted to the data acquisition unit to measure the light intensity. The measurement data is then transmitted to the data processing unit. The data processing unit calculates the absorbance of the analyte over time based on the light intensity, identifies the effective absorption peaks in the curve, and groups the absorbance values ​​of the effective absorption peaks into a measured absorbance group. The data processing unit also simulates and calculates the absorbance of each absorption peak at different temperatures, pressures, and concentrations, forming a simulated absorbance group. It then calculates the simulated absorbance group that best approximates the measured data, thus obtaining the temperature, pressure, and concentration values ​​of the analyte. The data output unit displays the data and curves from the measurement process, as well as the final measured value.

[0019] The output wavelength of the laser source is positively correlated with the irregular periodic driving voltage signal generated by the signal generator.

[0020] Compared with the prior art, the advantages of the present invention are as follows:

[0021] The present invention provides a gas multi-physical quantity measurement method and system that breaks through the range limit. By using a periodic non-monotonic irregular scanning drive mode of a signal generator, the output wavelength of the laser light source can be controlled to undergo periodic non-monotonic irregular changes, creating multiple artificial absorption peaks on the original absorbance curve of the component to be measured. Therefore, only one absorption line is needed to provide multiple absorption peak value data for the measurement of multiple physical quantities, without the need for multiple absorption lines. Compared with the existing two-line method measurement, this greatly reduces the measurement workload and system cost.

[0022] Secondly, peaks with high absorbance values, such as A0 and A1, do not satisfy A. min n max Under certain conditions, measurements can be continued using artificial absorption peaks with small absorbance values ​​to broaden the measurement range. Alternatively, the position of the artificial absorption peak can be changed by resetting the voltage generator's irregular periodic drive voltage signal f(t) to create an artificial peak with even smaller absorbance, further broadening the measurement range.​​

[0023] Therefore, the measuring method and the measuring system of the present application are simpler, and can be applied to a wider range of measurements of more physical quantities. BRIEF DESCRIPTION OF DRAWINGS

[0024] Figure 1 Flow chart of the measuring method of the present application;

[0025] Figure 2 Comparison chart of the wavelength curve of the laser light emitted by the light source in the measuring method of the present application and the prior art curve;

[0026] Figure 3 Comparison chart of the light intensity curve of the transmitted light measured in the measuring method of the present application and the prior art curve;

[0027] Figure 4 Comparison chart of the absorbance curve of the transmitted light measured in the measuring method of the present application and the prior art curve;

[0028] Figure 5 Structural schematic diagram of the measuring system of the present application. DETAILED DESCRIPTION

[0029] The concept, specific structure and technical effects of the present application will be further described below with reference to the accompanying drawings, so as to fully understand the purpose, features and effects of the present application.

[0030] It should be noted that in the description of the present application, the terms "upper", "lower", "left", "right", "vertical", "horizontal", "inner", "outer" and the like indicate the orientation or positional relationship shown in the drawings, which is a simplified description for the purpose of describing the present application, and does not mean that the elements must have a specific orientation, be constructed and operated in a specific orientation, and cannot be understood as a limitation on the present application.

[0031] The breakthrough range limit gas multi-physical quantity measuring method and system of the present application utilizes a signal generator to generate a special periodic driving voltage signal to control the periodic special change of the output light wavelength of the laser light source, to create multiple artificial peaks outside the absorption peak to form an absorption peak group, to set different temperatures, pressures and concentrations to simulate and calculate the absorbance of each wavelength of the absorption peak group to form a simulation data group, and then to obtain a measurement data group of the absorbance through actual measurement, to calculate the mean square error of the two, and the temperature, pressure and concentration of the simulation data group with the minimum error are the measurement values. Therefore, the present application can provide multiple absorption peak value data for measuring multiple physical quantities with only one absorption line, and when the peak with a large absorbance value does not meet the absorbance saturation condition, the artificial absorption peak with a small absorbance value can be used for further measurement to further widen the range.

[0032] The gas multi-physical quantity measurement method breaks through the range limit of the prior art, and has the advantages of Figure 1 The flow chart shows that the following steps are sequentially performed:

[0033] S1 determines the wavelengths of multiple artificial absorption peaks according to the maximum absorption wavelength of the component to be measured.

[0034] At the maximum absorption wavelength, the absorption intensity of the substance to light is the largest, and according to the standard spectrum of the component to be measured, the maximum absorption wavelength is determined, and n-1 artificial absorption peaks conforming to the test requirements are set on both sides of the maximum absorption wavelength, and the absorption peak at the maximum absorption wavelength is added, so that a total of n absorption peaks are obtained.

[0035] S2 designs a special periodic driving voltage signal function f(t) of a signal generator to control the periodic special change of the output light of the laser light source at the absorption peak and the artificial peak wavelength.

[0036] Reference Figure 2 b, the periodic special change refers to that the wavelength-time curve of the light source output light periodically fluctuates at the absorption peak wavelength selected in S1, rather than Figure 2 a monotone increasing or decreasing wavelength as in the prior art.

[0037] Specifically, the special periodic driving voltage signal f(t) is generated by the signal generator and sent to the laser controller, and the laser controller generates a corresponding special periodic driving current signal to control the periodic special change of the output light wavelength of the laser light source. The output light wavelength is positively correlated with the special periodic driving voltage signal.

[0038] S3 simulates the absorbance of each absorption peak at different temperatures, pressures and concentration values to form a simulated absorbance group.

[0039] For example, the wavelengths of the absorption peaks and the artificial absorption peaks are λ0, λ1, λ2…λ n , and the corresponding wave numbers are υ0, υ1, υ2…υ n , and the temperature T1, the pressure P1 and the concentration value C1 are set, and the simulated absorbance A(υ0), A(υ1), A(υ2)…A(υ n corresponding to the wavelengths are calculated according to the Lambert-Beer law formula (1), and a group of simulated absorbance values are obtained, and different temperatures, pressures and concentration values are set, so that multiple groups of absorbance values are obtained to form a simulated absorbance group.

[0040] A(v)=S(T)φ(v)PCL (1)

[0041] In the formula, T is the temperature [K]; S(T) [cm -2[ / atm] represents the absorption line intensity related to temperature T; φ(ν) [cm] is the normalized absorption line type function highly related to temperature and pressure; υ is the wavenumber of the incident light [cm]. -1 P is the pressure [atm]; C is the gas concentration; L [cm] is the absorption optical path length. All the spectroscopic parameters mentioned above are obtained from the HITRAN database or through pre-calibrated measurements.

[0042] The S4 test system is set up, and the data acquisition unit collects the output light of the laser source and the transmitted light signal of the output light through the component to be tested. The absorbance of the component to be tested is calculated, and the absorption peak is found in the absorbance change curve over time.

[0043] The S4.1 testing system includes a signal generator, a laser controller, and a laser source. The laser source outputs light to illuminate the sample chamber, and the data acquisition unit collects the transmitted light signal passing through the sample chamber.

[0044] The signal generator produces an irregularly shaped periodic driving voltage signal f(t), which is sent to the laser controller. The laser controller generates a corresponding irregularly shaped periodic driving current signal, causing the output wavelength of the laser source to change periodically. The sample chamber is used to hold the gas component to be tested. The data acquisition unit collects the transmitted light signal and performs calculations.

[0045] The absorption optical path length of the sample chamber is the same as L in formula (1) of S3.

[0046] S4.2 The sample chamber has two states: no gas and full of the gas to be tested. The data acquisition unit collects the transmitted light signal under the two conditions and plots two curves of light intensity change over time.

[0047] The output wavelength of the laser source changes periodically and irregularly. A photodetector receives the transmitted light signal as the laser beam sweeps across the sample chamber, converts the light signal into a voltage signal, and transmits it to the data acquisition unit. When the laser beam does not sweep across the analyte, the data acquisition unit acquires the transmitted light signal and outputs the transmitted light intensity I0 (hereinafter referred to as the reference intensity) without information about the analyte. When the laser beam passes over the analyte, the data acquisition unit acquires the light signal and outputs the transmitted light intensity I0 containing information about the analyte. t Two curves showing the change of light intensity over time were plotted. Figure 3 b), with Figure 3 The curve without artificial peaks shows significantly more fluctuations compared to the light intensity curve.

[0048] S4.3 Calculate the absorbance and plot the absorbance change curve over time.

[0049] Using the two sets of light intensity values ​​measured by S4.2, the absorbance A as a function of time t is calculated according to formula (2), and the curve of absorbance A as a function of time t is plotted. Figure 4b).

[0050]

[0051] The absorption peak is found in curve S4.4 in curve S4.3.

[0052] Figure 4 curve b and Figure 4 Compared to an artificially created curve, the absorbance curve has significantly more peaks. The absorbance curve is periodic, and data from multiple periods within the curve are all valid. Taking one period as an example, each group of absorption peaks consists of n absorption peaks within that period, including a combination of one original absorption peak and n-1 artificial peaks, with the highest peak being the original absorption peak.

[0053] S5 selects the effective absorption peaks from all absorption peaks, and the absorbance of the effective absorption peaks forms the absorbance measurement group.

[0054] As a screening method, the absorption peak between the absorbance corresponding to the absorbance at absorption saturation and the minimum absorbance that the system can detect is the effective absorption peak. The number of effective absorption peaks in one cycle must be greater than or equal to 3. If this is not met, S1 to S4 are repeated.

[0055] In the absorbance curve obtained in S4, taking one period as an example, the absorbance of all n absorption peaks are A0, A1, A2…A n (Absorbance is sorted from largest to smallest). In the computer, A0, A1, A2…A…are evaluated sequentially from largest to smallest. n Does it satisfy A? min i max i ranges from 1 to n, where A max The absorbance at absorption saturation can be taken as 3.3, A. min This is the minimum absorbance that the system can detect. If it is satisfied, it is a valid absorption peak; if not, the next absorbance is checked, and so on, until all n peaks have been checked and k usable absorption peaks are obtained, where k must be greater than or equal to 3. If satisfied, the operation of selecting a valid absorption peak continues for the next cycle; if not satisfied, the process starts from redesigning the irregular periodic drive voltage signal function f(t) of the signal generator and repeats S1 to S4.

[0056] The effective absorption peak k≥3 (k≤n) for each cycle ensures that the values ​​of the three physical quantities of temperature, pressure and concentration can be demodulated.

[0057] After selecting the effective absorption peaks from all the measurement data, the absorbance data of all the effective absorption peaks are combined into a measurement absorbance group. Therefore, the measurement absorbance group is a set of absorbance data, which contains the absorbance values ​​of k effective absorption peaks from multiple periods. ​​

[0058] S6 compares each set of values of the S3 simulated absorbance group with the S5 measured absorbance group, and the temperature, pressure, and concentration of the set of simulated absorbance values closest to the measured values are the temperature, pressure, and concentration values of the measured component.

[0059] The set of simulated absorbance values closest to the measured values can be determined by a method of solving the mean square error of the simulated absorbance group and the measured absorbance group. Specifically, according to formula (3), the mean square error of each set of absorbance values in the simulated absorbance group and the measured absorbance group is calculated in turn, for example, there are m sets of simulated absorbance values, m MSEs are obtained, and the temperature, pressure, and concentration values of the set of simulated absorbance values corresponding to the smallest MSE are the temperature, pressure, and concentration values of the measured component.

[0060]

[0061] The above measurement method is described below with specific examples.

[0062] The measured component in this example is CO, and the maximum absorption wavelength is 4854.6 nm. Two artificial absorption peaks greater than this wavelength can be created, and the signal generator voltage function is designed so that the output light of the laser light source has three periodically varying absorption peaks. According to formula (1), the absorbance A(υ0), A(υ1), and A(υ2) corresponding to the three absorption peak wavelengths (wavenumbers) under 900000 different conditions (temperature T = 1000-2000 K, pressure P = 0.5-5 atm, gas concentration C = 0-20000 ppm, optical path L = 20 cm) is simulated and calculated to form a simulated absorbance group. The light intensity-time curves of the test system under two conditions of having and not having the measured component are detected (for example, the light intensity-time curve of the test system under the condition of not having the measured component is shown in Figure 3 b), and the absorbance is calculated according to formula (2). The absorbance curve is shown in Figure 4 b, and it can be seen from Figure 4 b that the absorbances A0, A1, and A2 of the three absorption peaks are 1.216, 0.806, and 0.522, respectively, and the absorbance corresponding to the CO absorption saturation is A max , which is 3.3, and A min is the minimum absorbance 0.001 that can be detected by the system. A0, A1, and A2 are all between A min and A max , and all three are effective absorption peaks, so A0, A1, and A2 form a measured absorbance group. According to formula (3), the mean square error MSE between the measured absorbance group A0, A1, A2 and the 900000 simulated absorbance groups A(υ0), A(υ1), A(υ2) is calculated in a loop, and the smallest mean square error MSE is 0. The temperature T = 1600 K, pressure P = 1 atm, and gas concentration C = 10000 ppm of the simulated absorbance group with the smallest mean square error are the final measurement values.

[0063] The application also provides a gas multi-physical quantity measurement system breaking through the range limit, which comprises a signal generator, a laser controller, a laser light source, a sample chamber, a photoelectric detector and a data acquisition and processing system. Figure 5 The signal generator generates a special periodic driving voltage signal f(t) and sends it to the laser controller, and the laser controller generates a corresponding special periodic driving current signal to make the output light wavelength of the laser light source periodically change in a special shape.

[0064] The signal generator generates a special periodic driving voltage signal f(t) and sends it to the laser controller, and the laser controller generates a corresponding special periodic driving current signal to make the output light wavelength of the laser light source periodically change in a special shape.

[0065] The data acquisition and processing system comprises a data acquisition unit, a data processing unit and a data output unit. Figure 3 The data acquisition unit acquires the electrical signals transmitted by the photoelectric detector under the two conditions, measures the light intensity under the two conditions and transmits the light intensity to the data processing unit. Figure 4 The data processing unit draws two curves of light intensity changing with time (b), calculates a curve of absorbance of the measured component changing with time t, finds effective absorption peaks in the curve and forms a measured absorbance group with the absorbance values of the effective absorption peaks, and also simulates the absorbance under different temperature, pressure and concentration values to form a simulated absorbance group, calculates a group of simulated absorbances closest to the measured data, measures the temperature, pressure and concentration values of the measured component.

[0066] In order to facilitate the control of the signal generator, the output light wavelength of the laser light source is positively correlated with the special periodic driving voltage signal generated by the signal generator.

[0067] The gas multi-physical quantity measurement method and system breaking through the range limit of the application utilize the periodic non-monotonic special scanning driving mode of the signal generator to make the output light wavelength of the laser light source change periodically in a non-monotonic special shape, create multiple artificial absorption peaks on the original absorbance curve of the measured component, and thus only one absorption line can provide multiple absorption peak value data for measuring multiple physical quantities, without the need of multiple absorption lines.

[0068] In the case that the absorbance values of the peaks A0, A1 and the like are large and do not meet the condition A min <A n <A maxWhen the signal generator is re-set to a new voltage, the position of the artificial absorption peak can be changed, and a smaller artificial absorption peak can be created to further expand the range,

[0069] Therefore, the measuring process of the measuring method and the measuring system of the present application is simpler and more efficient, and the range is adjustable, so that the present application can be applied to the measurement of more physical quantities and more components.

[0070] The above embodiments are only used to illustrate the present application, but not to limit the present application. Although the present application has been described in detail with reference to the embodiments, it is understood that various combinations, modifications or equivalent replacements of the technical solutions of the present application can be made by those skilled in the art without departing from the spirit and scope of the present application, and all of them should be covered in the scope of the claims of the present application.

Claims

1. A method for measuring multiple physical quantities of gas that breaks through the range limit, characterized in that, Perform the following steps in sequence: S1 Determine the wavelengths of multiple artificial absorption peaks based on the maximum absorption wavelength of the component to be measured; S2 designs a signal generator with an irregularly shaped periodic driving voltage signal function f(t) to control the output light of the laser source to change periodically at the absorption peak and artificial peak wavelengths; S3 simulations calculate the absorbance of each absorption peak under different temperatures, pressures, and concentrations, forming a simulated absorbance group; The S4 test system is set up to collect the output light of the laser source and the transmitted light signal of the output light through the component to be tested using the data acquisition unit. The absorbance of the component to be tested is calculated, and the absorption peak is found in the absorbance change curve over time. S5. Select the effective absorption peaks from all absorption peaks. The absorbance of the effective absorption peaks forms the absorbance measurement group. The absorption peak between the absorbance corresponding to the absorption saturation and the minimum absorbance that the system can detect is the effective absorption peak. The number of effective absorption peaks in one cycle is greater than or equal to 3. If it is not satisfied, repeat S1 to S4. S6 compares each set of values ​​from the simulated absorbance group in S3 with the measured absorbance group in S5. The temperature, pressure, and concentration corresponding to the simulated absorbance value that is closest to the measured value are the measured temperature, pressure, and concentration values ​​of the analyte.

2. The method for measuring multiple physical quantities of gas that breaks through the range limit according to claim 1, characterized in that, In step S2, the signal generator generates an irregular periodic driving voltage signal f(t) and sends it to the laser controller. The laser controller generates a corresponding irregular periodic driving current signal, causing the output light wavelength of the laser source to change periodically. The output light wavelength is positively correlated with the irregular periodic driving voltage signal.

3. The method for measuring multiple physical quantities of gas beyond the range limit according to claim 1, characterized in that, Step S4 includes: The test system set up in S4.1 includes a signal generator, a laser controller, and a laser source. The laser source outputs light to illuminate the sample chamber, and the data acquisition unit collects the transmitted light signal passing through the sample chamber. S4.2 The sample chamber has two states: no gas and full of the gas to be tested. The data acquisition unit collects the transmitted light signals under both conditions and plots two curves of light intensity change over time. S4.3 Calculate the absorbance and plot the absorbance change curve over time; The absorption peak is found in curve S4.4 in curve S4.

3.

4. The method for measuring multiple physical quantities of gas beyond the range limit according to claim 1 or 3, characterized in that, In S6, the method of solving the mean square error between the simulated absorbance group and the measured absorbance group is used to determine the simulated absorbance group that is closest to the measured value.

5. The method for measuring multiple physical quantities of gas beyond the range limit according to claim 1, characterized in that, The formula for calculating absorbance using S3 simulation is: Where T is temperature; S(T) is the value related to temperature. T-related absorption lines are strong; It is a normalized absorption line function that is highly correlated with temperature and pressure; υ is the wavenumber of the incident light; P is the pressure; C is the gas concentration; and L is the absorption optical path.

6. A gas multi-physical quantity measurement system that breaks through the range limit, implementing the measurement method as described in claim 1, characterized in that, The system includes a signal generator, a laser controller, a laser source, a sample chamber, a photodetector, and a data acquisition and processing system. The signal generator produces a periodic driving voltage signal and sends it to the laser controller. The laser controller then generates a corresponding periodic driving current signal, causing the output wavelength of the laser source to change periodically. The wavelengths of the absorption peaks and artificial absorption peaks of the laser source output light are determined based on the maximum absorption wavelength of the analyte. The photodetector receives the light signal from the laser sweeping through the sample chamber and transmits it to the data acquisition and processing system. The data acquisition and processing system includes a data acquisition unit, a data processing unit, and a data output unit. The transmitted light signal from the sample chamber is converted into an electrical signal by a photodetector and transmitted to the data acquisition unit to measure the light intensity. The measured data is then transmitted to the data processing unit. The data processing unit calculates the absorbance of the analyte over time based on the light intensity, finds the effective absorption peaks in the curve, and forms a measured absorbance group by combining the absorbance values ​​of the effective absorption peaks. The data processing unit also simulates and calculates the absorbance of each absorption peak at different temperatures, pressures, and concentrations, forming a simulated absorbance group, and calculates the simulated absorbance group that is closest to the measured data, thus obtaining the temperature, pressure, and concentration values ​​of the analyte. The data output unit displays the data and curves from the measurement process, as well as the final measurement value.

7. The gas multi-physical quantity measurement system that breaks through the range limit according to claim 6, characterized in that, The output wavelength of the laser source is positively correlated with the irregular periodic driving voltage signal generated by the signal generator.

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