Alcohol concentration detection device and method

Abstract

The invention discloses an alcohol concentration detection device and method based on single-wavelength double light paths. The device comprises a light source module, a light beam shaping module, an absorption cell module, a double photoelectric detection module, an amplification and analog-to-digital conversion module and a processing module. In the technical scheme of the invention, the light source module emits a laser beam with single wavelength and stable power; the light beam shaping module collimates and splits the light beam into two light beams with different intensities, one light beam serves as a detection light beam and penetrates through the absorption cell module filled with a sample to be detected, and the other light beam serves as a reference light beam and is independently transmitted to a reference detection channel; a detection diode and a reference diode in the double photoelectric detection module respectively receive the detection light and the reference light and convert the detection light and the reference light into corresponding electric signals; the amplification and analog-to-digital conversion module carries out amplification and analog-to-digital conversion on the electric signal and outputs a digital signal to be read by the processing module; and the processing module performs ratio operation and data correction on the detection signal and the reference signal based on a preset algorithm, and finally calculates and outputs an alcohol concentration value. The online nondestructive detection of the alcohol concentration is realized, and the detection structure and principle are optimized. The method has the advantages of high precision, high real-time performance, portability, wide application range and the like.

Description

Technical Field

[0001] This invention relates to the field of photoelectric detection technology, and in particular to an alcohol concentration detection device and method. Technical Background

[0002] With the development of modern science and technology, alcohol and its products are widely used in food, scientific research, and industrial production. Alcohol concentration, as a core evaluation indicator, has a significant impact on the normal operation of these fields. Traditional alcohol concentration detection relies on destructive, high-consumption, and offline methods for quantitative analysis. These methods typically have the following problems:

[0003] 1) Significant differences in measurement accuracy: Some traditional alcohol concentration detection methods have significant shortcomings in accuracy. For example, the alcohol meter method relies on scale readings, which are prone to large deviations in the critical concentration region, and the measurement results are greatly affected by the operator's subjective judgment. In contrast, gas chromatography has higher detection accuracy and, as one of the authoritative means of substance concentration analysis, can achieve precise scanning and quantification of components. 2) Significant differences in real-time performance: In application scenarios that require both high accuracy and rapid response, traditional methods often struggle to achieve both. Although the alcohol meter method has a rapid response, its accuracy is insufficient; while gas chromatography provides accurate results, it cannot achieve real-time monitoring. 3) Limited applicability: Although some traditional methods are simple to operate, they usually require large sample volumes, resulting in high sample loss and limited accuracy; while chromatographic analysis techniques such as gas chromatography, although highly accurate, have strict requirements for the experimental environment, relying on specialized reagents, precision instruments, and professional technicians. The analytical process is complex and time-consuming, making it difficult to meet the needs of rapid detection. Therefore, under certain stringent conditions with high requirements for detection speed, accuracy, and environmental adaptability, existing methods all have certain limitations. Therefore, there is an urgent need for a setup and method that can accurately, quickly, online, and portablely detect alcohol concentration. Summary of the Invention

[0004] This invention provides an alcohol concentration detection device and method to solve the problems in the prior art where measurement accuracy and real-time monitoring cannot be simultaneously compatible with the detection environment.

[0005] According to one aspect of the present invention, an alcohol concentration detection device is provided, comprising:

[0006] A light source module, which is used to output a single-wavelength, untunable laser beam into the optical path;

[0007] The beam shaping module is used to collimate the focused beam output by the light source module and split the collimated beam into two beams of different intensities by a beam splitter. One beam is a weak beam used as a reference and the other beam is a strong beam used as a detection beam.

[0008] An absorption cell module is used to house and fix a quartz cuvette. The quartz cuvette is positioned and held by a self-designed fixing clamp, which is installed on the main structure of the device to achieve stable fixation of the quartz cuvette. The quartz cuvette is used to hold the alcohol solution sample to be tested, so that the second beam output by the beam shaping module can pass through the sample, and the concentration is measured according to the absorption characteristics of the target substance to light of a specific wavelength.

[0009] A dual photoelectric detection module includes two photodiodes. A first photodiode orthogonal to the main optical path receives the first light beam as a first signal. A second photodiode disposed along the main optical path receives the second light beam as a second signal. The dual photoelectric detection module converts the received optical signals into corresponding electrical signals.

[0010] The amplification and analog-to-digital conversion module is used to pre-amplify the weak analog electrical signal output by the dual photoelectric detection module and generate a digital signal through analog-to-digital conversion, so that the STM32F103RCT6 development board can read and analyze it later.

[0011] The processing module includes a regulated power supply unit, a voltage conversion circuit, an STM32F103RCT6 development board, a display module, and a computer. The processing module connects to the light source module, the dual photoelectric detection module, and the amplification and analog-to-digital conversion module, providing them with a stable operating voltage. Simultaneously, it receives digital signals from the amplification and analog-to-digital conversion module, runs a preset algorithm to perform ratio calculations and numerical corrections on the detected signal and reference signal, calculates the alcohol concentration value, and outputs the result through the display module or transmits it to the computer via a communication interface for display, recording, and further analysis.

[0012] Optionally, the light source module includes a semiconductor laser diode with a wavelength of 1290nm and a power of 5mW. The semiconductor laser diode contains an aspherical focusing lens with a focal length of 7.5mm, which is used to emit the first beam in the optical path.

[0013] Optionally, the beam shaping module includes a first plano-convex lens, a second plano-convex lens, and a cubic beam splitter prism. The first plano-convex lens is used to compress the beam radius and expand the beam. The second plano-convex lens is used to further expand the first beam, which has been compressed and expanded by the first plano-convex lens, to achieve a collimation effect. The cubic beam splitter prism is used to split the first beam, which has been collimated by the second plano-convex lens. The splitting ratio determines that the light intensities of the two beams are inconsistent. The weak light is used as the second beam, and the strong light is used as the third beam. They are respectively incident on the first photodiode and the second photodiode in the dual photodetector module.

[0014] Optionally, the dual photoelectric detection module includes a first photodiode and a second photodiode. The second beam is directly focused onto the first photodiode, causing a change in the first signal. The third beam passes through the absorption cell module and is focused onto the second photodiode, causing a change in the second signal.

[0015] Optionally, the absorption cell module is used to accommodate and fix a quartz cuvette. The quartz cuvette is positioned and held by a self-designed fixing clamp, which is installed on the main structure of the device to achieve stable fixation of the quartz cuvette. The quartz cuvette is used to hold the alcohol solution sample to be tested, so that the second beam output by the beam shaping module can pass through the sample, and the concentration is measured according to the absorption characteristics of the target substance to light of a specific wavelength.

[0016] Optionally, the dual photoelectric detection module is divided into two parts. One part is a reference part, which consists of a third plano-convex lens and a first photodiode, used to receive the second beam and serve as the system reference light intensity. The other part is a reference part, which consists of a fourth plano-convex lens and a second photodiode, used to receive the third beam and serve as the system detection light intensity. The two parts are used to obtain the third signal through a ratio algorithm. This method is used to eliminate light source jitter.

[0017] Matter absorption follows Lambert-Beer's law; when incident light passes through matter, it is absorbed. The mathematical relationship between the third beam and the first beam is as follows:

[0018] I3'=I3exp(-αcl)

[0019] Where I'3 is the light intensity emitted by the third beam after passing through the absorption cell module, I3 is the light intensity of the third beam, α is the absorption coefficient, c is the substance concentration, and l is the absorption optical path. Assuming the beam splitting ratio of the beam splitter is R:T, then the second beam is represented as R·I', and the light intensity of the third beam, I3, is represented as T·I1. The intensities received by the first photodiode and the second photodiode are then expressed as follows:

[0020] I 参 =R·I'

[0021] I 探 =T·I1exp(-αcl)

[0022] If the third signal ratio r is used for definition during signal analysis, then:

[0023]

[0024] After ratio processing, the third signal ratio r is a quantity that does not change with the incident light, thereby eliminating errors caused by light source jitter. In addition, the signal ratio r can effectively characterize the absorption properties of a substance.

[0025] Optionally, an amplification and analog-to-digital conversion module is used to pre-amplify the weak analog electrical signal output by the dual photoelectric detection module and generate a digital signal through analog-to-digital conversion, so that the STM32F103RCT6 development board can read and analyze it later.

[0026] Optionally, the processing module includes a regulated power supply unit, a voltage conversion circuit, an STM32F103RCT6 development board, a display module, and a computer. The processing module is connected to the light source module, the dual photoelectric detection module, and the amplification and analog-to-digital conversion module to provide them with a stable operating voltage. At the same time, it receives digital signals from the amplification and analog-to-digital conversion module, runs a preset algorithm to perform data processing such as ratio calculation and numerical correction on the detection signal and the reference signal, calculates the alcohol concentration value, and outputs the result through the display module or transmits it to the computer via the communication interface for display, recording, and further analysis.

[0027] Optionally, the processing module embeds a correction network model based on the random forest algorithm. The correction network model is obtained by jointly training a standard sample dataset collected under standard conditions and a noise dataset after introducing simulated noise into the standard dataset. In the actual detection process, the detection data from the amplification and analog-to-digital conversion module is processed by ratio analysis to become the third signal, which is then subjected to noise suppression and bias correction by the correction network model. The signal is then input into the continuous alcohol concentration prediction model calculated by interpolation to output the corrected alcohol concentration value.

[0028] According to another aspect of the present invention, an alcohol concentration detection device is provided, wherein the alcohol concentration detection method is performed using the above-described alcohol concentration detection device, the alcohol concentration detection method comprising:

[0029] S1. Turn on the voltage regulator unit, voltage conversion circuit integrated module, computer, STM32F103RCT6 development board and display module in the processing module to provide a stable voltage supply for the system.

[0030] S2. Open the light source module, the dual photoelectric detection module, the amplification and analog-to-digital conversion module. The first beam emitted from the semiconductor laser diode in the light source module will be shaped and split by the first plano-convex lens, the second plano-convex lens, and the cubic beam splitter prism in the beam shaping module to obtain the second beam and the third beam. Wait for the value in the display module in the processing module to stabilize.

[0031] S3. Remove the quartz cuvette from the absorption cell module, slowly inject the liquid sample to be tested into the quartz cuvette, and then place it in the fixing fixture in the absorption cell module. Wait for the second beam split from the beam shaping module to be focused into the first photodiode by the third plano-convex lens in the dual photoelectric detection module, and wait for the third beam split from the beam shaping module to be focused into the first photodiode by the fourth plano-convex lens in the dual photoelectric detection module to interact with it. Wait for the response of the first photodiode and the second photodiode.

[0032] S4. Wait for the signal amplification and analog-to-digital conversion process of the integrated amplification and analog-to-digital conversion module in the amplification and analog-to-digital conversion module, wait for the processing of the STM32F103RCT6 development board in the processing module, and after the value in the display module stabilizes, the output result of alcohol concentration in the computer and the display module can be read.

[0033] The alcohol concentration detection device provided in this embodiment of the invention includes: a light source module, a beam shaping module, an absorption cell module, a dual photoelectric detection module, an amplification and analog-to-digital conversion module, and a processing module. The light source module, dual photoelectric detection module, and amplification and analog-to-digital conversion module are all connected to the processing module. The light source module outputs a stable laser beam to the beam shaping module; the beam shaping module performs operations such as radius compression, beam expansion, and beam splitting on the beam to achieve the output of the first beam and the second beam; the third beam output by the beam shaping module passes through the quartz cuvette of the absorption cell module and interacts with the liquid sample to be tested; the detection part of the dual photoelectric detection system detects the light emitted after interacting with the liquid sample in the absorption cell module and calibrates it as the second signal; the second beam output by the beam shaping module is directly focused into the reference part of the dual photoelectric detection module and calibrated as the first signal. The voltage rise caused by the photodiode after being exposed to light is processed by the amplification and analog-to-digital conversion module, and amplified by differential method. The analog-to-digital conversion section converts the differentially amplified voltage signal into a digital signal and inputs it into the STM32103RCT6 development board. The detection data from the amplification and analog-to-digital conversion module is subjected to noise suppression and deviation correction by the correction network model constructed by the random forest algorithm embedded in the processing module. The data is then input into the continuous part alcohol concentration prediction model calculated by interpolation to output the corrected alcohol concentration value. This solves the problem that the measurement accuracy and real-time monitoring cannot be simultaneously compatible with the detection environment in the existing technology.

[0034] It should be understood that the description in this section is not intended to identify key or essential features of the embodiments of the present invention, nor is it intended to limit the scope of the invention. Other features of the invention will become readily apparent from the following description. Attached Figure Description

[0035] To more clearly illustrate the technical solutions in the embodiments of the present invention, the accompanying drawings used in the description of the embodiments will be briefly introduced below. Obviously, the accompanying drawings described below are only some embodiments of the present invention. For those skilled in the art, other drawings can be obtained based on these drawings without creative effort.

[0036] Figure 1 This is a structural block diagram of an alcohol concentration detection device provided in an embodiment of the present invention;

[0037] Figure 2 This is a schematic diagram of the structure of an alcohol concentration detection device provided in an embodiment of the present invention;

[0038] Figure 3 This is a schematic flowchart of an alcohol concentration detection method provided in an embodiment of the present invention;

[0039] Figure 4 This is a schematic diagram of a data correction logic provided in an embodiment of the present invention. Detailed Implementation

[0040] To enable those skilled in the art to better understand the present invention, the technical solutions of the present invention will be clearly and completely described below with reference to the accompanying drawings of the embodiments. Obviously, the described embodiments are only some embodiments of the present invention, and not all embodiments. Based on the embodiments of the present invention, all other embodiments obtained by those skilled in the art without creative effort should fall within the scope of protection of the present invention.

[0041] It should be noted that the terms "first," "second," etc., in the specification, claims, and accompanying drawings of this invention are used to distinguish similar objects and are not necessarily used to describe a specific order or sequence. It should be understood that such data can be interchanged where appropriate so that the embodiments of the invention described herein can be implemented in orders other than those illustrated or described herein. Furthermore, the terms "comprising" and "having," and any variations thereof, are intended to cover a non-exclusive inclusion; for example, a process, method, system, product, or apparatus that comprises a series of steps or units is not necessarily limited to those steps or units explicitly listed, but may include other steps or units not explicitly listed or inherent to such processes, methods, products, or apparatus.

[0042] Figure 1 This is a structural block diagram of an alcohol concentration detection device provided in an embodiment of the present invention. Figure 2 This is a schematic diagram of an alcohol concentration detection device provided in an embodiment of the present invention, with reference to... Figure 1 and Figure 2 The alcohol concentration detection device includes a light source module 100, which outputs a laser beam of fixed intensity to a quartz cuvette 5 containing the sample to be tested, fixed in a fixture 6 within the absorption cell module 300. Optionally, the light source module includes a semiconductor laser diode 1, which is composed of an aspherical focusing lens with a wavelength of 1290 nm, a power of 5 mW, and an internal focal length of 7.5 mm.

[0043] A beam shaping module 200 is used to shape the first beam emitted from the semiconductor laser diode 1. Optionally, the beam shaping module includes a first plano-convex lens 2, a second plano-convex lens 3, and a beam-splitting cubic prism 4. The first beam is focused during propagation, then compressed and expanded by the first plano-convex lens 2. The second plano-convex lens 3 collimates the first beam expanded by the first plano-convex lens 2, and then it is incident on the beam-splitting cubic prism 4. The beam-splitting cubic prism has a splitting ratio that can split the collimated first beam into the second beam and the third beam. It should be noted that in this system, the first plano-convex lens 2, the second plano-convex lens 3, and the beam-splitting cubic prism 4 are fixed using a coaxial system. The purpose of compressing the beam radius is that the light-facing surface of the quartz cuvette 5 in the absorption cell module has a certain width requirement, and the beam radius cannot exceed the width of the light-facing surface.

[0044] The absorption cell module 300 includes a quartz cuvette 5 and its self-designed fixing fixture 6. Its main function is to hold the liquid sample to be tested and fix it to ensure that the detection value will not change due to the change in absorption intensity caused by the slight shaking or displacement during the experiment.

[0045] The dual photoelectric detection module (reference part) 400 mainly receives the second beam split from the beam shaping module 200 and converts it into a usable first signal. Optionally, the dual photoelectric detection module (reference part) consists of a third plano-convex lens 7 and a first photodiode 8. The second beam is focused by the third plano-convex lens 7 and incident on the detection window of the first photodiode 8, causing a change in the electrical properties of its internal material, resulting in a voltage rise in the circuit, which is then output through a signal cable.

[0046] The dual photoelectric detection module (detection section) 500 mainly receives the light emitted after the third beam split from the beam shaping module 200 is absorbed by the liquid sample to be tested placed in the quartz cuvette 5 in the absorption cell module 300, and converts it into a second signal. Optionally, the dual photoelectric detection module (detection section) consists of a fourth plano-convex lens 9 and a second photodiode 10. The weak light is focused by the fourth plano-convex lens 9 and incident on the detection window of the second photodiode 10, causing a change in the electrical properties of its internal material, resulting in a voltage rise in the circuit, which is then output through the signal line.

[0047] The amplification and analog-to-digital conversion module 600 includes an amplification and analog-to-digital conversion circuit 10. Its main function is to process the electrical signals output from the dual photoelectric detection module 400 and the dual photoelectric detection module 500, amplify them, and convert them into readable digital signals for easy recognition, processing, and calculation by the STM32103RCT6 development board.

[0048] The processing module 700 is connected to the light source module 100, the dual photoelectric detection module 400, the dual photoelectric detection module 500, and the amplification and analog-to-digital conversion module 600. The processing module 700 includes an integrated module 12 with an integrated regulated power supply and voltage conversion circuit, a computer 13, an STM32103RCT6 development board 14, and a display module 15, which are used to connect the various modules, receive and send relevant information, and display the concentration output results.

[0049] The technical solution of this invention uses the emitted light from the liquid sample to be tested by the dual photoelectric detection module and the reference light split by the beam shaping module as the detection subjects to achieve high-precision detection of alcohol concentration. The optical path structure and measurement principle are optimized to reduce the impact of measurement error and accuracy loss caused by the instability of the light source. This invention has the advantages of being accurate, fast-responding, online, portable, and highly adaptable to the environment.

[0050] Figure 3 This is a schematic diagram of an alcohol concentration detection process provided by an embodiment of the present invention. The alcohol concentration measurement method is executed using the alcohol concentration detection device provided in the above embodiment. (Refer to...) Figure 2 and Figure 3 The method for measuring alcohol concentration includes:

[0051] S1. Turn on the voltage regulator unit, voltage conversion circuit integrated module 11, computer 13, STM32F103RCT6 development board 14, and display module 15 in the processing module 700 to provide a stable voltage supply for the system.

[0052] S2. Turn on the light source module 100, the dual photoelectric detection module 400, the dual photoelectric detection module 500, and the amplification and analog-to-digital conversion module 600. The first beam emitted from the semiconductor laser diode 1 in the light source module 100 will be shaped and split by the first plano-convex lens 2, the second plano-convex lens 3, and the cubic beam splitter prism 4 in the beam shaping module 200 to obtain the second beam and the third beam. Wait for the value in the display module 15 in the processing module 700 to stabilize.

[0053] S3. Remove the quartz cuvette 5 from the absorption cell module 300, slowly inject the liquid sample to be tested into the quartz cuvette 5, and then place it into the fixing clamp 6 in the absorption cell module. Wait for the second beam split from the beam shaping module 200 to be focused into the first photodiode 8 by the third plano-convex lens 7 in the dual photoelectric detection module 400, and wait for the third beam split from the beam shaping module 200 to be focused into the first photodiode 10 by the fourth plano-convex lens 9 in the dual photoelectric detection module 500 to interact with it, and wait for the response of the first photodiode and the second photodiode.

[0054] S4. Wait for the signal amplification and analog-to-digital conversion process of the integrated amplification and analog-to-digital conversion module 11 in the amplification and analog-to-digital conversion module 600, wait for the processing of the STM32F103RCT6 development board 14 in the processing module 700, and after the value in the display module 15 stabilizes, the output result of alcohol concentration in the computer 14 and the display module 15 can be read.

[0055] The technical solutions of the embodiments of the present invention have the following effects:

[0056] 1) Real-time online measurement improves detection efficiency:

[0057] This invention enables real-time detection of changes in alcohol concentration, avoiding the lag inherent in traditional offline measurement methods. Real-time online measurement allows users to obtain timely information on changes in alcohol concentration, enabling rapid response and improving detection efficiency and productivity.

[0058] 2) Employing a dual photoelectric detection method ensures detection stability:

[0059] By employing a dual photoelectric detection method, a reference signal intensity value is incorporated into the signal processing, and subsequent calculations are performed using the signal ratio method. This effectively reduces the measurement error and accuracy impact caused by laser power jitter, ensuring detection stability.

[0060] 3) Fewer samples are required for measurement, reducing sample waste:

[0061] The sample required for measurement is far less than that required by traditional measurement methods such as alcohol meters, densitometers and gas chromatography. A single measurement requires less than 10 mm, which can greatly reduce waste for some high-cost samples.

[0062] 4) No other samples are required, and the detection process is simple:

[0063] The test requires no additional reagents or samples, and the process is highly automated. Simply place the sample in and wait a few moments to get accurate results.

[0064] Figure 4 This is a schematic diagram of a data correction logic provided in an embodiment of the present invention. The alcohol concentration measurement method is executed using the processing module in the alcohol concentration detection device provided in the above embodiment. (Refer to...) Figure 4 The data correction logic method includes:

[0065] First, a large amount of measurement data is collected using pre-configured standard samples. This initial collection involves gathering data from single-concentration samples, gradually increasing the sample size and expanding the dimensionality of the standard dataset. Next, Gaussian noise is introduced to simulate interference generated within the device, creating an interference dataset. A random forest algorithm is then used to calculate a fragmented forest numerical correction network model for both datasets. This model is a distributed model. Interpolation methods are then used to interpolate data to adapt to continuous distributions. Finally, the data collected using the device is input into this correction model to obtain the actual concentration output.

[0066] The specific embodiments described above do not constitute a limitation on the scope of protection of this invention. Those skilled in the art should understand that various modifications, combinations, sub-combinations, and substitutions can be made according to design requirements and other factors. Any modifications, equivalent substitutions, and improvements made within the spirit and principles of this invention should be included within the scope of protection of this invention.

Claims

1. An alcohol concentration detection device, characterized in that, include: A light source module, which is used to output a single-wavelength, non-tunable power laser beam into the optical path; A beam shaping module is used to collimate a non-parallel beam into a parallel beam and split the beam into two beams, a strong beam and a weak beam, using a beam splitter prism. An absorption cell module is used to support and fix a quartz cuvette for holding a liquid sample to be tested. The dual photoelectric detection module is equipped with two photodiodes. The photodiode facing the optical path is used to receive strong light from the beam splitter and is used for detection. The photodiode perpendicular to it is used to receive weak light from the beam splitter and is used for reference. An amplification and analog-to-digital conversion module is used to amplify and convert the signal from the dual photoelectric detection module into an analog-to-digital signal for subsequent reading and analysis by the STM32 system. The processing module includes a regulated power supply, a voltage conversion module, a computer, an STM32 development board, and a display module. It is used to connect to the light source module, the dual photoelectric detection module, and the amplification and analog-to-digital conversion module. It is used to receive and send relevant information and process the information according to the pre-set code to achieve concentration output.

2. The alcohol concentration detection device according to claim 1, characterized in that, The light source module includes a semiconductor laser diode with a wavelength of 1290nm and a power of 5mW, and the semiconductor laser diode contains an aspherical focusing lens with a focal length of 7.5mm.

3. The alcohol concentration detection device according to claim 1, characterized in that, The beam shaping module includes a first plano-convex lens, a second plano-convex lens, and a cubic beam splitter. The first plano-convex lens is used to compress the beam radius, and the second plano-convex lens is used to further expand the beam of light that has been compressed and expanded by the first plano-convex lens to achieve a collimation effect. The cubic beam splitter is used to split the collimated beam. The splitting ratio determines that the light intensities of the two beams are not the same, one beam is strong light and the other is weak light, which are respectively incident on the dual photoelectric detection module.

4. The alcohol concentration detection device according to claim 3, characterized in that, The dual photoelectric detection module includes a detection photodiode and a reference photodiode. The strong light will pass through the absorption cell module and be focused onto the detection photodiode, while the weak light will be directly focused onto the reference photodiode.

5. The alcohol concentration detection device according to claim 4, characterized in that, The absorption cell module consists of a fixing clamp and a quartz cuvette. The fixing clamp is fixed to a stainless steel coaxial rod. The quartz cuvette has an absorption optical path of 20 mm and is used to hold the liquid sample to be tested.

6. The alcohol concentration detection device according to claim 1, characterized in that, The dual photoelectric detection module is divided into two parts: a detection part, consisting of a third plano-convex lens and a detection photodiode, used to receive the light passing through the absorption cell module; and a reference part, consisting of a fourth plano-convex lens and a reference photodiode, used to receive the weak light and use it as the system reference light intensity to eliminate light source jitter. The absorption of light by matter follows the Lambert-Beer law. When incident light passes through matter and is absorbed, the mathematical relationship between the outgoing and incident light is as follows: I = I0exp(-αcl) Where I is the emitted light, I0 is the incident light, α is the absorption coefficient, c is the substance concentration, and l is the absorption optical path. Let the intensity of the light source module be I', and the splitting ratio of the beam splitter be R:T. Then, the strong light is represented as T·I', and the weak light is represented as R·I'. The intensities received by the detection photodiode and the reference photodiode are then expressed as follows: I 探 =T·I'exp(-αcl) I 参 =R·I’ In signal analysis, the signal ratio r is used for definition, then: After ratio processing, the signal ratio r is a quantity that does not change with the incident light, thereby eliminating errors caused by light source jitter. In addition, the signal ratio r can effectively characterize the absorption properties of a substance.

7. The alcohol concentration detection device according to claim 1, characterized in that, The amplification and analog-to-digital conversion module is used to process the voltage rise caused by the photodiode after being exposed to light, and amplifies it using the differential method. The analog-to-digital conversion section converts the differentially amplified voltage signal into a digital signal and inputs it into the STM32 system.

8. The alcohol concentration detection device according to claim 1, characterized in that, The processing module includes a DC regulated power supply, a voltage conversion module, a computer, an STM32 development board, and a display module. The DC regulated power supply is connected to the voltage conversion module, which is used to connect to the light source module and the amplification and analog-to-digital conversion module. The STM32 development board is used to connect to the amplification and analog-to-digital conversion module, and the computer is used to connect to and control the use and debugging of the STM32 development board.

9. The alcohol concentration detection device according to claim 1, characterized in that, The processing module has an embedded correction network model based on the random forest algorithm. The correction network model is obtained by jointly training a standard sample dataset collected under standard conditions and an enhanced dataset after introducing simulated noise into the standard dataset. In the actual detection process, the detection data from the amplification and analog-to-digital conversion module is first subjected to noise suppression and bias correction by the correction network model, and then input into the alcohol concentration prediction model to output the corrected alcohol concentration value.

10. An alcohol concentration detection device, characterized in that, The alcohol concentration detection method is performed using the alcohol concentration detection device according to any one of claims 1 to 9, and includes: S1. Turn on the light source module to output a laser beam. After being collimated by the beam shaping module, the beam is split into two beams of different intensities by the beam splitter: one strong beam is used as the measurement optical path, and the other weak beam is used as the reference optical path. S2. The strong light passes through the quartz cuvette in the absorption cell module in sequence and interacts with the liquid sample to be tested. Some of the light is absorbed and then emitted to form an attenuated measurement signal; the weak light bypasses the absorption cell and enters the reference light path directly. S3. The detection photodiode in the dual photoelectric detection module receives the measurement signal, and the reference photodiode receives the reference signal, and converts them into electrical signals respectively. The S4 amplification and analog-to-digital conversion module performs differential amplification on the two electrical signals and converts the analog voltage signal into a digital signal through analog-to-digital conversion, which is then transmitted to the STM32 development board. S5. The processing module receives the digital signal and calculates the ratio r of the measured signal to the reference signal to eliminate the system error caused by the fluctuation of the light source intensity. S6. Input the original detection data corresponding to the ratio r into the embedded correction network model based on the random forest algorithm, perform noise suppression and system bias correction on the data, and obtain the corrected feature signal. S7. Input the corrected feature signal into the alcohol concentration prediction model and output the alcohol concentration value of the liquid sample to be tested. S8 displays and transmits the test results via computer, STM32 development board, and display module.

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