CN117269118A - Non-contact alcohol concentration measuring method and device - Google Patents
Non-contact alcohol concentration measuring method and device Download PDFInfo
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- CN117269118A CN117269118A CN202311100418.5A CN202311100418A CN117269118A CN 117269118 A CN117269118 A CN 117269118A CN 202311100418 A CN202311100418 A CN 202311100418A CN 117269118 A CN117269118 A CN 117269118A
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- LFQSCWFLJHTTHZ-UHFFFAOYSA-N Ethanol Chemical compound CCO LFQSCWFLJHTTHZ-UHFFFAOYSA-N 0.000 title claims abstract description 171
- 238000000034 method Methods 0.000 title claims abstract description 20
- 238000002834 transmittance Methods 0.000 claims abstract description 44
- 238000005259 measurement Methods 0.000 claims abstract description 29
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- 229910000530 Gallium indium arsenide Inorganic materials 0.000 claims description 2
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- 230000001678 irradiating effect Effects 0.000 abstract description 4
- 239000000243 solution Substances 0.000 description 89
- 238000005070 sampling Methods 0.000 description 13
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- XLYOFNOQVPJJNP-UHFFFAOYSA-N water Substances O XLYOFNOQVPJJNP-UHFFFAOYSA-N 0.000 description 4
- 238000000326 densiometry Methods 0.000 description 3
- 229920006395 saturated elastomer Polymers 0.000 description 3
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- 150000001298 alcohols Chemical class 0.000 description 1
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Classifications
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- G—PHYSICS
- G01—MEASURING; TESTING
- G01N—INVESTIGATING OR ANALYSING MATERIALS BY DETERMINING THEIR CHEMICAL OR PHYSICAL PROPERTIES
- G01N21/00—Investigating or analysing materials by the use of optical means, i.e. using sub-millimetre waves, infrared, visible or ultraviolet light
- G01N21/17—Systems in which incident light is modified in accordance with the properties of the material investigated
- G01N21/59—Transmissivity
-
- G—PHYSICS
- G01—MEASURING; TESTING
- G01N—INVESTIGATING OR ANALYSING MATERIALS BY DETERMINING THEIR CHEMICAL OR PHYSICAL PROPERTIES
- G01N21/00—Investigating or analysing materials by the use of optical means, i.e. using sub-millimetre waves, infrared, visible or ultraviolet light
- G01N21/17—Systems in which incident light is modified in accordance with the properties of the material investigated
- G01N21/25—Colour; Spectral properties, i.e. comparison of effect of material on the light at two or more different wavelengths or wavelength bands
- G01N21/27—Colour; 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
-
- G—PHYSICS
- G01—MEASURING; TESTING
- G01N—INVESTIGATING OR ANALYSING MATERIALS BY DETERMINING THEIR CHEMICAL OR PHYSICAL PROPERTIES
- G01N21/00—Investigating or analysing materials by the use of optical means, i.e. using sub-millimetre waves, infrared, visible or ultraviolet light
- G01N21/17—Systems in which incident light is modified in accordance with the properties of the material investigated
- G01N21/25—Colour; Spectral properties, i.e. comparison of effect of material on the light at two or more different wavelengths or wavelength bands
- G01N21/31—Investigating relative effect of material at wavelengths characteristic of specific elements or molecules, e.g. atomic absorption spectrometry
- G01N21/39—Investigating relative effect of material at wavelengths characteristic of specific elements or molecules, e.g. atomic absorption spectrometry using tunable lasers
Abstract
The invention provides a non-contact alcohol concentration measuring method and a non-contact alcohol concentration measuring device, comprising the following steps: irradiating a cuvette containing an alcohol solution to be measured by utilizing laser of an infrared band emitted by a light source; the infrared photoelectric detector receives transmitted light which is transmitted through the alcohol solution to be detected from the other side of the cuvette; calculating the transmittance of the alcohol solution to be measured; and calculating the concentration of the alcohol solution to be detected based on the functional relation between the laser transmittance with the wavelength lambda of the alcohol solution and the concentration of the alcohol solution. The invention realizes the non-contact alcohol concentration measurement with high efficiency, high precision and low cost.
Description
Technical Field
The invention belongs to the technical field of alcohol concentration measurement, and particularly relates to a non-contact alcohol concentration measurement method and device.
Background
Alcohol is a mixed solution of ethanol and water. As a common organic solvent, alcohol has wide application in daily life, medical and health, food industry and industrial and agricultural production. In life, edible alcohol can be used for blending white spirit; in the medical field, 70-75% ethanol solution is commonly used for medical disinfection, 40-50% ethanol can prevent bedsores, and 25-50% ethanol can be used for physical defervescence; in the industrial and agricultural fields, alcohols are raw materials for producing solvents such as varnishes, cosmetics, inks, paint removers, and agricultural chemicals, medicines, rubbers, plastics, rayon, detergents, and the like. The concentration can be the decisive factor for determining the purpose of the alcohol solution, so that the accurate, rapid and convenient measurement of the alcohol concentration is of great significance.
The measurement modes of alcohol concentration can be divided into two types, namely contact measurement and non-contact measurement, and the contact measurement scheme is mature at present, and is widely applied to the market, and typical methods include densitometry, refractometry and alcohol gravimetry.
The alcohol densitometry was designed based on the difference in density of ethanol and water: the density of the ethanol is smaller than that of the water, the higher the concentration of the ethanol is, the smaller the buoyancy force born by an alcohol densimeter in the alcohol solution is, and the measurement of the concentration of the ethanol can be realized by reading the scale calibrated in advance on the densimeter. However, the alcohol densitometry is cumbersome to operate, requires manual readings, and consumes a large amount of alcohol solution.
Alcohol refractometry is designed based on the refractive index differences of alcohol solutions of different concentrations: the concentration of alcohol is measured by measuring the angle of deflection of light after passing through the alcohol solution and converting the angle into the refractive index of the solution. However, alcohol refractometry also requires manual readings and measurement errors are large for high concentration alcohol solutions.
The alcohol specific gravity method is used for measuring the density of the alcohol solution by measuring the buoyancy of the standard glass weight in the alcohol solution and calculating the density of the alcohol solution, so that the alcohol concentration is measured. The method has the advantages of complicated operation steps, larger measurement error and higher device cost.
The contact type measuring device has the problems of heavy volume, complex operation, higher cost and the like. And are not suitable for some applications where small amounts of sampling and rapid measurements are required.
Disclosure of Invention
Aiming at the problems existing in the prior art, the invention provides a non-contact alcohol concentration measuring method and device, which realize non-contact alcohol concentration measurement with high efficiency, high precision and low cost.
In order to achieve the technical purpose, the invention adopts the following technical scheme:
a non-contact alcohol concentration measuring method comprising the steps of:
the infrared laser diode with the wavelength lambda directly irradiates the infrared photoelectric detector, and the infrared photoelectric detector measures to obtain the forward light intensity I 0 The back light intensity detected by the photoelectric detector in the infrared laser diode is I' 0 ；
The infrared laser diode with the wavelength lambda irradiates an infrared photoelectric detector after penetrating through the alcohol solution to be detected, and the infrared photoelectric detector measures to obtain forward light intensity I 1 The back light intensity detected by a photoelectric detector in the laser diode is I 1 'A'; calculating the laser transmittance T of the alcohol solution to be measured with the wavelength lambda,
and calculating the concentration of the alcohol solution to be measured based on the functional relation between the laser transmittance of the alcohol solution with the wavelength lambda and the concentration of the alcohol solution.
Further, in a preferred embodiment of the present invention, the laser wavelength λ is 1310nm.
Furthermore, the method adopts the alcohol solution with known concentration to calibrate the laser transmittance with the wavelength lambda, and the function relation between the laser transmittance with the wavelength lambda of the alcohol solution and the concentration of the alcohol solution is obtained by calibrating, wherein the function relation between the laser transmittance with the wavelength lambda of the alcohol solution and the concentration of the alcohol solution is obtained by fitting an e index model.
In another aspect, the present invention provides a non-contact alcohol concentration measuring apparatus, comprising:
the cuvette is used for containing an alcohol solution to be measured;
an infrared laser diode for emitting laser light with a wavelength lambda;
the infrared photoelectric detector is used for directly irradiating the laser with the wavelength lambda emitted by the infrared laser diode, and the forward light intensity measured by the infrared photoelectric detector is I 0 At the same time, the back light intensity monitored inside the infrared laser diode is I' 0 The method comprises the steps of carrying out a first treatment on the surface of the The laser with the wavelength lambda emitted by the infrared laser diode irradiates an infrared photoelectric detector after penetrating through a cuvette containing alcohol solution, and the infrared photoelectric detector measures to obtain forward light intensity I 1 The back light intensity detected by a photoelectric detector in the laser diode is I 1 '
A data processing unit for calculating the laser transmittance T of the alcohol solution to be measured with the wavelength lambda,and calculating the concentration of the alcohol solution to be measured based on the functional relation between the laser transmittance of the alcohol solution with the wavelength lambda and the concentration of the alcohol solution.
Further, as a preferable mode of the invention, the laser wavelength lambda is 1310nm, and the optical path of the cuvette is 10mm. Based on the function relation between 1310nm laser transmittance of the alcohol solution and the concentration of the alcohol solution, the concentration c= 81.103 ×ln (T) -268.691 of the alcohol solution to be detected is calculated.
Compared with the prior art, the invention has the following beneficial technical effects:
aiming at the problems that the existing alcohol solution concentration measuring device is heavy in volume, complex in operation and high in cost, is not applicable to occasions requiring a small amount of sampling and quick measurement, the invention provides a non-contact alcohol concentration measuring scheme with high efficiency, high precision and low cost, the measuring scheme can greatly reduce the volume of the measuring device, and the measuring result is accurate and reliable.
Drawings
In order to more clearly illustrate the embodiments of the present invention or the technical solutions in the prior art, the drawings that are required in the embodiments or the description of the prior art will be briefly described, and it is obvious that the drawings in the following description are only some embodiments of the present invention, and other drawings may be obtained according to the structures shown in these drawings without inventive effort for a person skilled in the art.
FIG. 1 is a schematic diagram of an embodiment of the present invention;
FIG. 2 is a schematic diagram of another embodiment of the present invention;
FIG. 3 is a diagram of an infrared band laser diode driving circuit and a photodetector signal amplifying circuit according to an embodiment of the present invention;
FIG. 4 is a graph showing the relationship between the laser transmittance of an alcohol solution and the concentration of the alcohol solution (measured using a 10mm optical path cuvette), wherein (a) is an infrared absorption spectrum of alcohol solutions of different concentrations; (b) A graph of the laser transmittance in the wavelength range of 1280nm to 1380nm along with the concentration change of the alcohol solution;
FIG. 5 is a graph of 1310nm laser transmittance fit (measured using a 10mm optical path cuvette) for alcohol solutions of different concentrations in one embodiment;
reference numerals in the drawings:
1. a data processing unit; 2. an infrared laser diode; 3. a cuvette; 4. an infrared photodetector; 5. a high-precision AD sampling module; 6. a wireless communication module; 7. a display module; 8. a power supply module; 9. and the power conversion module, 10 and the client.
The achievement of the objects, functional features and advantages of the present invention will be further described with reference to the accompanying drawings, in conjunction with the embodiments.
Detailed description of the preferred embodiments
For the purpose of making the objects, technical solutions and advantages of the embodiments of the present invention more apparent, the spirit of the present disclosure will be clearly described in the following drawings and detailed description, and any person skilled in the art, after having appreciated the embodiments of the present disclosure, may make alterations and modifications by the techniques taught by the present disclosure without departing from the spirit and scope of the present disclosure. The exemplary embodiments of the present invention and the descriptions thereof are intended to illustrate the present invention, but not to limit the present invention.
In one embodiment, a method for measuring alcohol concentration in a non-contact manner is provided, comprising the steps of:
the infrared laser diode with the wavelength lambda directly irradiates the infrared photoelectric detector, and the infrared photoelectric detector measures to obtain the forward light intensity I 0 The back light intensity detected by the photoelectric detector in the infrared laser diode is I' 0 ；
The infrared laser diode with the wavelength lambda irradiates an infrared photoelectric detector after penetrating through the alcohol solution to be detected, and the infrared photoelectric detector measures to obtain forward light intensity I 1 The back light intensity detected by a photoelectric detector in the laser diode is I 1 'A'; calculating the laser transmittance T of the alcohol solution to be measured with the wavelength lambda,
and calculating the concentration of the alcohol solution to be measured based on the functional relation between the laser transmittance of the alcohol solution with the wavelength lambda and the concentration of the alcohol solution. The measurement accuracy can be greatly improved by selecting a laser with a proper wavelength. The invention provides that alcohol solutions with different concentrations have different absorptivity in the infrared band, and the concentration of the alcohol solution can be calculated by measuring the transmittance of alcohol to infrared light. In order to determine the optimal infrared band for measurement and verify the feasibility of the scheme provided by the invention, the laser transmittance of the alcohol solution in the infrared band of 900-1700 nm is measured.
Selecting a cuvette with an optical path of 10mm for testing, and outputting an infrared band of 900-1700 nm by using a supercontinuum light source to irradiate alcohol solutions with different concentrations. Fig. 4 is a graph of the relationship between the laser transmittance of an alcohol solution and the concentration of the alcohol solution, wherein fig. 4 (a) shows a graph of infrared absorption spectra of 900nm to 1700nm for alcohol solutions of different concentrations, and different infrared bands in the graph are divided into an absorption region having no significant change with concentration, an absorption region having significant change with concentration, and a saturated absorption region. In a spectral region where absorption does not change obviously with concentration, the laser transmittance of alcohol solutions with different concentrations does not change obviously, and the method is not suitable for actual measurement; in the saturated absorption region, alcohol solutions with different concentrations generate obvious absorption and are not suitable for testing; however, in the 'absorption with concentration significant change region', the transmittance of alcohol with different concentrations is obviously different, and the method is suitable for measuring the alcohol concentration. Consider that 1310nm is located in the "absorption-concentration significant change region" and its transmittance change range (alcohol concentration 0-100% vol) is larger than other wavelengths, as shown in FIG. 4 (b). Furthermore, 1310nm is a typical communication band, and a corresponding Laser Diode (LD) is also mature, and a 1310nm laser is preferable in consideration of the above.
The 1310nm laser transmittance of the alcoholic solution was analyzed as follows. Assuming that the absorption rate of ethanol in 1310nm band is alpha 1 The absorptivity of water in 1310nm wave band is alpha 2 The concentration of the alcohol solution is c, the optical path of the cuvette is L, and the incident light intensity is I 0 Neglecting the absorption of the cuvette to light, the transmitted light intensity I 1 Can be expressed as:
I 1 ＝I 0 exp{-[α 1 cL+α 2 (1-c)L]}
＝I 0 exp{-[(α 1 -α 2 )cL+α 2 L]}
the above formula illustrates that the concentration c and transmittance of the alcohol solution should satisfy an exponential relationship.
The optical path is 10mm cuvette, the 1310nm laser transmittance of alcohol solutions with different concentrations is measured and calibrated, and the mathematical model of the e index function is used for fitting, so that the result shown in figure 5 is obtained, and the data fitting condition is good.
And obtaining the function relation between 1310nm laser transmittance of the alcohol solution and the concentration of the alcohol solution through data fitting. Based on the above relation, the 1310nm laser transmittance of the alcohol solution to be measured is measured, and the concentration c= 81.103 ×ln (T) -268.691 of the alcohol solution to be measured can be calculated.
Referring to fig. 1, in one embodiment, there is provided a non-contact alcohol concentration measuring apparatus including:
the cuvette 3 is used for containing an alcohol solution to be measured; the infrared laser diode 2 is used as a light source for emitting laser with wavelength lambda to irradiateCuvette 3 containing alcohol solution to be measured, the forward light intensity of the laser when directly irradiating the photodetector is I 0 At this time, the back light intensity monitored inside the laser diode is I' 0 The method comprises the steps of carrying out a first treatment on the surface of the The back light intensity monitored by the laser diode when the laser irradiates the cuvette containing the alcohol solution is I 1 '；
An infrared photodetector 4 for receiving the transmitted light intensity I transmitted through the alcohol solution to be measured from the other side of the cuvette 3 1 ；
The high-precision AD sampling module 5 samples the signal output by the infrared photoelectric detector 4 and transmits the sampled signal to the data processing unit for processing;
a data processing unit 1 for calculating the laser transmittance T of the alcohol solution to be measured with the wavelength lambda,and calculating the concentration of the alcohol solution to be detected based on the functional relation between the laser transmittance of the alcohol solution with the wavelength lambda and the concentration of the alcohol solution.
An infrared laser diode 2 of 1310nm is used as a light source in one embodiment. Measuring 1310nm laser transmittance of the alcohol solution to be measured, and calculating the concentration c= 81.103 ×ln (T) -268.691 of the alcohol solution to be measured based on the functional relation between the 1310nm laser transmittance of the alcohol solution and the concentration of the alcohol solution.
Referring to fig. 2, an embodiment provides a non-contact alcohol concentration measuring device, which comprises a data processing unit 1, an infrared laser diode 2, a cuvette 3, an infrared photoelectric detector 4, a high-precision AD sampling module 5, a wireless communication module 6, a display module 7, a power supply module 8, a power conversion module 9 and a client 10. The data processing unit 1 is connected with the infrared laser diode 2 and is used for pulse driving the infrared laser diode 2. The data processing unit 1 is connected with a wireless communication module 6, and is in communication connection with a client 10 through the wireless communication module 6, and the client 10 can remotely control the data processing unit 1, so as to control the whole measurement process and obtain a measurement result in real time. It can be understood that each electric device included in the present invention (not limited to the present embodiment) is powered by a power source, the power source module includes a power source module 8 and a power source conversion module 9, and the power source conversion module 9 converts the voltage of the power source module 8 into the working voltage of each electric device to power each electric device, so as to maintain the normal operation of each electric device.
The data processing unit is connected with a display module, so that real-time display of measurement results is realized.
The cuvette 3 is used for containing an alcohol solution to be measured, and the optical path of the cuvette is 10mm.
An infrared laser diode 2 with 1310nm is used as a light source for emitting laser with 1310nm wavelength to irradiate a cuvette 3 containing an alcohol solution to be measured, and the forward light intensity measured by the 1310nm laser when directly irradiating an infrared photoelectric detector 4 is I 0 At this time, the back light intensity monitored by the photodetector inside the infrared laser diode 2 is I' 0 ；
The infrared light emitted by the 1310nm infrared laser diode 2 is received by the infrared photoelectric detector 4 after passing through the cuvette 3 containing the alcohol solution, and the infrared photoelectric detector 4 detects the light intensity I of the transmitted light passing through the alcohol solution to be detected 1 At the same time, the back light intensity monitored by the photoelectric detector inside the infrared laser diode 2 is I 1 '；
The high-precision AD sampling module 5 samples the signal output by the infrared photoelectric detector 4 and transmits the sampled signal to the data processing unit for processing.
The data processing unit 1 calculates the transmittance T of the alcohol solution to be measured,based on the functional relation between 1310nm laser transmittance of the alcohol solution and the concentration of the alcohol solution under the condition that the optical path of the cuvette obtained through calibration is 10mm, the concentration c= 81.103 ×ln (T) -268.691 of the alcohol solution to be measured can be calculated.
In one embodiment, the structure shown in fig. 2 is employed, wherein:
the singlechip development board adopted by the data processing unit 1 is Arduino Nano.
The high-precision AD sampling module is a microminiature ADS1115 high-precision sampling chip (16 bits).
The infrared photoelectric detector is an InGaAs photoelectric detector with the wavelength response range of 800 nm-1700 nm.
The wireless communication module adopts a Bluetooth module, and the Bluetooth module is JDY-31 type Bluetooth.
The client can be designed as a mobile phone client APP.
The power supply module is two sections of 3.7V 18650 rechargeable batteries, and the power supply conversion module is an A0509S voltage conversion module. The display module adopts a 0.96 inch OLED display screen and adopts an SSD1306 control chip.
Working principle: firstly, clicking a measurement button of a mobile phone client APP when a cuvette is not placed, sending a first character of a control word such as a character 'a' to a singlechip development board by the mobile phone client APP through a Bluetooth module, and waiting for receiving data returned by the singlechip development board. At this time, the singlechip development board drives 1310nm infrared laser diode LD to generate a certain amount of light pulses, and the relative light intensity I at this time is recorded by the high-precision AD sampling module 0 /I' 0 And after the completion, sending a zero setting completion to the mobile phone client APP for display. After placing the cuvette containing the alcohol solution to be measured, clicking a measurement button on the mobile phone client APP, sending a second control character such as character b to the singlechip development board by the mobile phone client APP through the Bluetooth module, and waiting for receiving the return data of the singlechip development board. At this time, the singlechip development board generates a certain amount of light pulses by driving 1310nm infrared laser diode LD, and records the relative light intensity I at this time by a high-precision AD sampling module 1 /I 1 ', and will I 1 /I 1 ' and I 0 /I' 0 The ratio of the 1310nm infrared laser transmittance T of the alcohol solution to be measured is used as the actual alcohol solution concentration c calculated through a relation curve of the 1310nm infrared laser transmittance of the alcohol solution and the alcohol concentration calibrated in advance, and a measurement result is sent to a mobile phone client APP for display after the actual alcohol solution concentration c is completed.
The alcohol concentration measuring device is communicated with the mobile phone client APP through the Bluetooth module, and the alcohol concentration measuring device is controlled to conduct measurement operation by sending a measurement instruction through the mobile phone. When the mobile phone control device performs zero setting operation, the singlechip records the transmittance when the alcohol solution is not placed once; when the mobile phone controls the measuring device to perform 'measuring', the singlechip records the transmittance after the alcohol solution is placed once, and calculates the concentration of the alcohol solution at the moment. The alcohol solution measurement can be displayed on an OLED display screen and a mobile phone interface.
Referring to fig. 3, an embodiment employs a simple infrared band laser diode driving circuit and a photodetector signal amplifying circuit diagram.
Wherein, the infrared laser diode driving circuit adopts a simple common emitter driving circuit, and the base electrode of the triode passes through a resistor R B And the D2 pin is connected to the singlechip. When the D2 pin outputs low level, the triode is cut off, and the LD does not emit light; when the D2 pin outputs high level, the triode is saturated and conducted, and the LD emits light. Pulse driving of the infrared laser diode can be realized by changing the high and low levels of the D2 pin of the singlechip.
The photodetector signal amplification circuit includes a forward light receiving circuit portion and a backward light receiving circuit portion. The circuit configuration thereof is substantially symmetrical, and thus the forward light receiving circuit therein will be described. The infrared photoelectric detector 4 is correspondingly provided with a forward light receiving circuit, which is used for amplifying the electric signal output by the infrared photoelectric detector 4 so as to improve the sensitivity and the precision of the measurement of the infrared photoelectric detector.
When the laser irradiates the infrared photodetector, the infrared photodetector PD1 generates a laser beam with a size I p The photocurrent is converted into a photocurrent with the size of U after passing through a resistor R5 1 ＝I p ×R 5 Is provided. Wherein the capacitor C2 functions to filter out noise in the signal. U (U) 1 The size of the first-stage operational amplifier is changed into U 2 ＝(1+R 7 /R 6 )×U 1 And sampled by an AD sampling module. Wherein the resistor R8 is a pull-up resistor. The weak current change caused by the transmittance change is amplified by the designed amplifying circuit, and the sensitivity and the accuracy of the infrared photoelectric detector measurement are effectively improved. Wherein, the voltage signal U amplified by the amplifying circuit 2 Can not exceed AD sampling modeThe sampling range of the block to avoid saturation.
The structure of the back light receiving circuit is basically consistent with that of the forward light receiving circuit, and only the photo detector PD0 in the back light receiving circuit is the photo detector integrated in the infrared laser diode 2 and can be used for monitoring the back scattered light of the infrared laser diode 2.
The ratio of the forward light intensity measured by the infrared photoelectric detector 4 to the backward light intensity monitored by the photoelectric detector inside the infrared laser diode 2 can be calculated to obtain the relative light intensity, so that the influence of the self power instability of the infrared laser diode on the measurement accuracy and stability is eliminated greatly.
The mode of collecting the return light can avoid the light splitting monitoring of output power, unnecessary light path structures such as a spectroscope are not needed to be introduced, and the system structure is simplified as much as possible while the influence of unstable factors of the laser diode power is eliminated.
The invention is not a matter of the known technology.
The technical features of the above embodiments may be arbitrarily combined, and all possible combinations of the technical features in the above embodiments are not described for brevity of description, however, as long as there is no contradiction between the combinations of the technical features, they should be considered as the scope of the description.
The above examples merely represent a few embodiments of the present application, which are described in more detail and are not to be construed as limiting the scope of the invention. It should be noted that it would be apparent to those skilled in the art that various modifications and improvements could be made without departing from the spirit of the present application, which would be within the scope of the present application. Accordingly, the scope of protection of the present application is to be determined by the claims appended hereto.
Claims (10)
1. The non-contact alcohol concentration measuring method is characterized by comprising the following steps of:
infrared laser with wavelength lambdaThe polar tube directly irradiates an infrared photoelectric detector, and the infrared photoelectric detector measures to obtain forward light intensity I 0 The back light intensity detected by the photoelectric detector in the infrared laser diode is I' 0 ；
The infrared laser diode with the wavelength lambda irradiates an infrared photoelectric detector after penetrating through the alcohol solution to be detected, and the infrared photoelectric detector measures to obtain forward light intensity I 1 The back light intensity detected by a photoelectric detector in the laser diode is I 1 'A'; calculating the laser transmittance T of the alcohol solution to be measured with the wavelength lambda,
and calculating the concentration of the alcohol solution to be measured based on the functional relation between the laser transmittance of the alcohol solution with the wavelength lambda and the concentration of the alcohol solution.
2. The method for measuring the concentration of alcohol without contact according to claim 1, wherein the laser wavelength λ is 1310nm.
3. The method for measuring the concentration of alcohol in a non-contact manner according to claim 2, wherein the calibration of the laser transmittance with the wavelength lambda is performed by using the alcohol solution with the known concentration, and the calibration is performed to obtain the functional relationship between the laser transmittance with the wavelength lambda of the alcohol solution and the concentration of the alcohol solution, wherein the functional relationship between the laser transmittance with the wavelength lambda of the alcohol solution and the concentration of the alcohol solution is obtained by fitting an e-index model.
4. A non-contact alcohol concentration measuring apparatus, comprising:
the cuvette is used for containing an alcohol solution to be measured;
an infrared laser diode for emitting laser light with a wavelength lambda;
the infrared photoelectric detector is used for detecting the forward direction when the infrared photoelectric detector is directly irradiated by the laser with the wavelength lambda emitted by the infrared laser diodeThe light intensity is I 0 At the same time, the back light intensity monitored inside the infrared laser diode is I' 0 The method comprises the steps of carrying out a first treatment on the surface of the The laser with the wavelength lambda emitted by the infrared laser diode irradiates an infrared photoelectric detector after penetrating through a cuvette containing alcohol solution, and the infrared photoelectric detector measures to obtain forward light intensity I 1 The back light intensity detected by a photoelectric detector in the laser diode is I 1 '；
A data processing unit for calculating the laser transmittance T of the alcohol solution to be measured with the wavelength lambda,and calculating the concentration of the alcohol solution to be measured based on the functional relation between the laser transmittance of the alcohol solution with the wavelength lambda and the concentration of the alcohol solution.
5. The non-contact alcohol concentration measuring apparatus according to claim 4, wherein a 1310nm laser is used as the light source.
6. The non-contact alcohol concentration measuring apparatus according to claim 4 or 5, wherein: the infrared photoelectric detector is an InGaAs photoelectric detector with the wavelength response range of 800 nm-1700 nm.
7. The non-contact alcohol concentration measuring apparatus according to claim 4 or 5 or 6, wherein: the cuvette optical path is 10mm.
8. The non-contact alcohol concentration measuring device according to claim 7, wherein the concentration of the alcohol solution to be measured is c= 81.103 ×ln (T) -268.691.
9. The non-contact alcohol concentration measuring apparatus according to claim 4, wherein: the data processing unit is also used for driving the light source in a pulse mode and controlling the light source to output light pulses.
10. The non-contact alcohol concentration measuring apparatus according to claim 4, wherein: the data processing unit is connected with a wireless communication module, and is in communication connection with the client through the wireless communication module, and the client can remotely control the data processing unit;
the data processing unit is connected with a display module, so that real-time display of measurement results is realized.
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| Application Number | Priority Date | Filing Date | Title |
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| CN202311100418.5A CN117269118A (en) | 2023-08-30 | 2023-08-30 | Non-contact alcohol concentration measuring method and device |
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| CN202311100418.5A CN117269118A (en) | 2023-08-30 | 2023-08-30 | Non-contact alcohol concentration measuring method and device |
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| CN117269118A true CN117269118A (en) | 2023-12-22 |
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