阅读说明：本技术 酒驾检测方法及系统 (Drunk driving detection method and system ) 是由 李绍民 孙利群 于 2020-06-05 设计创作，主要内容包括：本发明提供了一种酒驾检测方法及系统,其中,所述酒驾检测方法,包括：将激光射入待检测的驾驶室；以及探测所述射入待检测的驾驶室的激光漫反射回来的光,由此定量确定所述待检测的驾驶室内的酒精路径积分浓度。本发明酒驾检测方法及系统无需设卡拦车辆,方便快捷、效率高、节省了人力成本。(The invention provides a drunk driving detection method and system, wherein the drunk driving detection method comprises the following steps: injecting laser into a cab to be detected; and detecting the light diffusely reflected by the laser emitted into the cab to be detected, so as to quantitatively determine the integrated concentration of the alcohol path in the cab to be detected. The drunk driving detection method and the drunk driving detection system do not need to block the vehicle, are convenient and quick, have high efficiency and save the labor cost.)

1. A drunk driving detection method is characterized by comprising the following steps:

injecting laser into a cab to be detected; and

and detecting the light diffusely reflected by the laser emitted into the cab to be detected, thereby quantitatively determining the integrated concentration of the alcohol path in the cab to be detected.

2. The drunk driving detection method according to claim 1, wherein detecting the light diffusely reflected by the laser beam entering the cab to be detected, thereby quantitatively determining the alcohol path integral concentration in the cab to be detected, comprises:

determining the ratio V of the second harmonic maximum value of the first absorption peak of water vapor in the cab to be detected to the first harmonic value at the second harmonic maximum value through the light diffusely reflected by the laser emitted into the cab to be detected₁And the ratio V of the second harmonic maximum of the second absorption peak of the water vapor to the first harmonic value at this second harmonic maximum₂；

Determining the alcohol path integral concentration C based on wavelength modulation spectroscopy_eL_eAnd said V₁、V₂Thereby quantitatively determining the integrated alcohol path concentration in the cab to be tested.

3. The drunk driving detection method as claimed in claim 2, further comprising, before quantitatively determining the alcohol path integral concentration in the cab to be detected:

determining the alcohol pathway integral concentration by calibrationFunction relation parameter k_w1、k_w2And

based on the alcohol path integral concentration function relation, V₁And V₂And the parameter k of said functional relation_w1、k_w2、Quantitatively determining the integrated concentration of the alcohol path in the cab to be detected;

wherein the alcohol path integral concentration function formula is

4. The drunk driving detection method as claimed in claim 3, wherein the alcohol path integral concentration function relation parameter k is determined by calibration_w1、k_w2Andthe method comprises the following steps:

calibrating by using standard concentration gradient water vapor, and determining function relation parameter k_w1、k_w2；

Calibrating by using ethanol gas with standard concentration gradient, and determining function relation parameters

5. The drunk driving detection method as claimed in claim 4, wherein the scaling of the integral concentration of the water vapor path is determined by filling the gas pool with water vapor in a series of concentration gradients, respectively, as the ratio of the second harmonic maximum at the first absorption peak of the water vapor to the first harmonic value at the second harmonic maximumA standard line of water vapor path integral concentration, and a ratio of the second harmonic maximum value at the second absorption peak of water vapor to the first harmonic value at the second harmonic maximum value, wherein the slopes of the two standard lines are respectively a function relation parameter k_w1、k_w2。

6. The drunk driving detection method as claimed in claim 4, wherein the ratio of the second harmonic maximum at the first absorption peak of water vapor to the first harmonic value at the second harmonic maximum and the ratio of the second harmonic maximum at the second absorption peak of water vapor to the first harmonic value at the second harmonic maximum are determined by filling a series of ethanol gas with concentration gradient in the gas pool, and the determined function relation parameter k is combined_w1、k_w2To obtainAnd C_eL_eThereby determining the relationship between

7. The drunk driving detection method according to claim 1, wherein laser light is emitted into a cab to be detected through a windshield; and detecting the light diffusely reflected by the laser emitted into the cab to be detected.

8. A drunk driving detection system, comprising:

the tunable semiconductor laser is used for injecting laser into a cab to be detected; and

the photoelectric detector is used for detecting the light diffusely reflected by the laser emitted into the cab to be detected;

and the drunk driving detection system quantitatively determines the alcohol path integral concentration in the cab to be detected by using the light reflected by the diffuse reflection.

9. The drunk driving detection system of claim 8, further comprising:

and the upper computer is used for determining the alcohol path integral concentration in the cab to be detected according to the signal detected by the photoelectric detector.

Technical Field

The invention relates to the technical field of remote sensing, in particular to a drunk driving detection method and system.

Background

Drunk driving has great threat to the life and property safety of people, and the death and injury ratio caused by drunk driving is great among all casualties in traffic accidents. According to the International Traffic Safety Data and Analysis Group (IRTAD), in 2010 at 2000-. The data of the ministry of public security shows that 90 thousands of drunk driving investigation places exist in China in the last half of 2019.

However, according to the research, the drunk driving check rate is very low, and the reason is mainly that the drunk driving check mode is to block the vehicle by a traffic police card and enable a driver to blow air to detect drunk driving at present, and the mode is long in time consumption, low in efficiency and large in manpower requirement. However, obviously, due to the fact that the labor cost is high, a plurality of vehicles cannot be detected, only random detection can be achieved, and the problem that drunk driving has great threat to the safety of life and property of people cannot be effectively solved.

Therefore, a fast and efficient drunk driving detection method and system capable of saving labor cost are needed.

Disclosure of Invention

Technical problem to be solved

In view of the above problems, it is a primary object of the present invention to provide a drunk driving detection method and system, so as to at least partially solve at least one of the above mentioned technical problems.

(II) technical scheme

According to an aspect of the present invention, there is provided a drunk driving detection method, including:

injecting laser into a cab to be detected; and

and detecting the light diffusely reflected by the laser emitted into the cab to be detected, thereby quantitatively determining the integrated concentration of the alcohol path in the cab to be detected.

Further, detecting the light diffusely reflected by the laser beam emitted into the cab to be detected, thereby quantitatively determining the integrated concentration of the alcohol path in the cab to be detected, including:

determining the ratio V of the second harmonic maximum value of the first absorption peak of water vapor in the cab to be detected to the first harmonic value at the second harmonic maximum value through the light diffusely reflected by the laser emitted into the cab to be detected₁And the ratio V of the second harmonic maximum of the second absorption peak of the water vapor to the first harmonic value at this second harmonic maximum₂；

Determining the alcohol path integral concentration C based on wavelength modulation spectroscopy_eL_eAnd said V₁、V₂Thereby quantitatively determining the integrated alcohol path concentration in the cab to be tested.

Further, before quantitatively determining the integrated concentration of the alcohol path in the cab to be detected, the method further comprises the following steps:

determining the alcohol path integral concentration function relation parameter k through calibration_w1、k_w2And

based on the alcohol path integral concentration function relation, V₁And V₂And the parameter k of said functional relation_w1、k_w2、Quantitatively determining the integrated concentration of the alcohol path in the cab to be detected;

wherein the alcohol path integral concentration function formula is

Further, determining the alcohol path integral concentration function relation parameter k through calibration_w1、k_w2Andthe method comprises the following steps:

calibrating by using standard concentration gradient water vapor, and determining function relation parameter k_w1、k_w2；

Calibrating by using ethanol gas with standard concentration gradient, and determining function relation parameters

Further, a series of concentration gradient water vapor is filled in the gas pool, a standard line of the integral concentration of the water vapor path, namely the ratio of the maximum value of the second harmonic at the first absorption peak of the water vapor to the first harmonic value at the maximum value of the second harmonic, and a standard line of the integral concentration of the water vapor path, namely the ratio of the maximum value of the second harmonic at the second absorption peak of the water vapor to the first harmonic value at the maximum value of the second harmonic are respectively determined, and the slopes of the two standard lines are respectively a function relation parameter k_w1、k_w2。

Further, ethanol gas with a series of concentration gradients is filled in the gas pool respectivelyDetermining the ratio of the second harmonic maximum at the first absorption peak of the water vapor to the first harmonic value at the second harmonic maximum and the ratio of the second harmonic maximum at the second absorption peak of the water vapor to the first harmonic value at the second harmonic maximum, and combining the determined function relation parameter k_w1、k_w2To obtainAnd C_eL_eThereby determining the relationship between

Further, injecting laser into a cab to be detected through a windshield; and detecting the light reflected by the laser emitted into the cab to be detected in a diffuse way (after diffuse reflection, the light is transmitted by the windshield).

According to another aspect of the present invention, there is provided a drunk driving detection system including:

the tunable semiconductor laser is used for injecting laser into a cab to be detected; and

the photoelectric detector is used for detecting the light diffusely reflected by the laser emitted into the cab to be detected;

and the drunk driving detection system quantitatively determines the alcohol path integral concentration in the cab to be detected by using the light reflected by the diffuse reflection.

Further, the method also comprises the following steps: and the upper computer is used for determining the alcohol path integral concentration in the cab to be detected according to the signal detected by the photoelectric detector.

(III) advantageous effects

According to the technical scheme, the drunk driving detection method and the drunk driving detection system have at least one of the following beneficial effects:

(1) laser is injected into a cab to be detected through a windshield; the light reflected by the laser which is injected into the cab to be detected in a diffuse mode is detected, so that the alcohol path integral concentration in the cab to be detected is determined quantitatively, a vehicle does not need to be blocked, convenience and rapidness are realized, the efficiency is high, and the labor cost is saved.

(2) The method is used for detecting drunk driving based on the wavelength modulation spectrum technology, and determining the alcohol path integral concentration, and has the advantages of high sensitivity, strong selectivity and high time resolution.

(3) The interference of water vapor to the alcohol path integral concentration detection is effectively eliminated through twice calibration, and the accuracy of drunk driving detection is improved.

Drawings

The accompanying drawings, which are incorporated in and constitute a part of this specification, illustrate an embodiment of the invention and, together with the description, serve to explain the invention and not to limit the invention. In the drawings:

FIG. 1 is a graph showing the absorption curves of water vapor and ethanol gas in comparison with the absorption curves of the present invention (abscissa: wave number, unit is cm-1).

FIG. 2 is a simulation graph of the present invention.

Fig. 3 is a schematic structural diagram of the drunk driving detection system of the invention.

Description of reference numerals: 1. a tunable semiconductor laser; 2. a laser pigtail; 3. a fiber collimator; 4. a semiconductor laser driving unit and a temperature control unit; 5. a function signal generation unit; 6. an upper computer; 7. an analog-to-digital conversion unit; 8. the photoelectric detector comprises a photoelectric detector current-voltage conversion unit and a signal amplification unit; 9. a photodetector; 10. a light-collecting lens.

Detailed Description

In order that the objects, technical solutions and advantages of the present invention will become more apparent, the present invention will be further described in detail with reference to the accompanying drawings in conjunction with the following specific embodiments.

The invention provides a drunk driving detection method, which comprises the following steps:

injecting laser into a cab to be detected; and

and detecting the light diffusely reflected by the laser emitted into the cab to be detected, thereby quantitatively determining the integrated concentration of the alcohol path in the cab to be detected.

Optionally, laser is injected into a cab to be detected through a windshield; and detecting the light diffusely reflected by the laser emitted into the cab to be detected, thereby quantitatively determining the integrated concentration of the alcohol path in the cab to be detected. Of course, it is not limited to the windshield.

Therefore, the drunk driving detection method can quantitatively obtain the concentration (ppm level) of alcohol gas by using laser to enter the cab through the front windshield of a normally traveling automobile and detecting the light reflected by diffuse reflection, and traffic police do not need to set a card to check the stopped automobile. Moreover, the drunk driving detection method does not need a cooperation target, is very convenient to implement, only needs to be arranged above a road, and is similar to a monitoring camera. The method can be implemented in the near infrared band, and compared with a method in the intermediate infrared band, the cost of the light source and the detector can be reduced by 8-10 times.

Specifically, the detecting the light diffusely reflected by the laser beam entering the cab to be detected to quantitatively determine the integrated concentration of the alcohol path in the cab to be detected includes:

determining the ratio V of the second harmonic maximum value of the first absorption peak of water vapor in the cab to be detected to the first harmonic value at the second harmonic maximum value through the light diffusely reflected by the laser emitted into the cab to be detected₁And the ratio V of the second harmonic maximum of the second absorption peak of the water vapor to the first harmonic value at this second harmonic maximum₂；

Determining the alcohol path integral concentration C based on wavelength modulation spectroscopy_eL_eAnd said V₁、V₂The functional relation of (1);

determining the alcohol path integral concentration function relation parameter k through calibration_w1、k_w2And

based on the alcohol path integral concentration function relation, V₁And V₂And the parameter k of said functional relation_w1、k_w2、Quantitatively determining the integrated concentration of the alcohol path in the cab to be detected;

wherein the alcohol path integral concentration function formula is

The method is used for detecting drunk driving based on the wavelength modulation spectrum technology, and determining the alcohol path integral concentration, and has the advantages of high sensitivity, strong selectivity and high time resolution.

At the time of actual drunk driving detection, the alcohol path integral concentration C_eL_eThe quantity to be solved in the relational expression is an unknown quantity; the function relation between the V and the V₁、V₂、k_w1、k_w2、In connection with, said k_w1、k_w2、Can be obtained by calibration, and can become a known quantity; the V is₁、V₂The alcohol path integral concentration C can be obtained by detecting the light diffusely reflected by the laser emitted into the cab to be detected, namely, the light can also be a known quantity, and the alcohol path integral concentration C can be obtained by the known quantity in the functional relation_eL_e。

More specifically, the alcohol path integral concentration function relation parameter k is determined by calibration_w1、k_w2Andthe method comprises the following steps:

calibrating by using standard concentration gradient water vapor (water vapor calibration for short), and determining function relation parameter k_w1、k_w2: by filling a series of water vapor with concentration gradient in the gas pool, respectivelyDetermining a standard line of the integral concentration of the water vapor path as the ratio of the second harmonic maximum value at the first absorption peak of the water vapor to the first harmonic value at the second harmonic maximum value, and a standard line of the integral concentration of the water vapor path as the ratio of the second harmonic maximum value at the second absorption peak of the water vapor to the first harmonic value at the second harmonic maximum value, wherein the slopes of the two standard lines are respectively a function relation parameter k_w1、k_w2。

Calibrating by using ethanol gas with standard concentration gradient (ethanol calibration for short), and determining function relation parametersFilling a series of concentration gradient ethanol gas into a gas pool (demarcating the gas pool to control the gas concentration and the optical path of light), respectively determining the ratio of the second harmonic maximum value at the first absorption peak of the water vapor to the first harmonic value at the second harmonic maximum value and the ratio of the second harmonic maximum value at the second absorption peak of the water vapor to the first harmonic value at the second harmonic maximum value, and combining the determined function relation parameter k_w1、k_w2To obtainAnd C_eL_eThereby determining the relationship between

When the ethanol gas is calibrated (calibration is carried out before drunk driving detection), the ethanol gas with standard concentration gradient is used for calibration, and the ethanol gas with known concentration, namely the integrated concentration C of the ethanol path, is used at the moment_eL_eIs a known amount; the V is₁、V₂The light can be measured by detecting the light diffusely reflected by the laser emitted into the cab to be detected, and is also known quantity; k is_w1、k_w2The amount to be solved in the ethanol calibration process is obtained in the water vapor calibration process and is also known amount

Determining the alcohol path integral concentration by a slope method or an interpolation method. Regarding interpolation, the principle is simple, namely, the interpolation is obtained in the ethanol calibration processAnd C_eL_eA plurality of data points (in the x-y coordinate system), then in the actual measurement, it is possible to determine the data points based on(From measured V₁、V₂And scaled k_w1、k_w2Get) to interpolate between data points to get C_eL_e。

The invention also provides a drunk driving detection system, which comprises:

the tunable semiconductor laser is used for injecting laser into a cab to be detected; and

the photoelectric detector is used for detecting the light diffusely reflected by the laser emitted into the cab to be detected;

and the drunk driving detection system quantitatively determines the alcohol path integral concentration in the cab to be detected by using the light reflected by the diffuse reflection.

Further, the drunk driving detection system further comprises: and the upper computer is used for determining the alcohol path integral concentration in the cab to be detected according to the signal detected by the photoelectric detector.

The method and the system are used for detecting drunk driving based on a Wavelength Modulation spectrum technology (WMS), which is a branch of a tunable laser absorption spectrum Technology (TDLAS). The method is used for detecting drunk driving based on the wavelength modulation spectrum technology, and has the advantages of high sensitivity, strong selectivity, high time resolution and the like.

The alcohol concentration remote sensing method is characterized in that the calibration is carried out by utilizing the water vapor with the standard concentration gradient, then the calibration is carried out by utilizing the ethanol gas with the standard concentration gradient, and after the calibration is finished, the alcohol concentration remote sensing can be realized, so that the remote sensing of drunk driving is realized. Thus, the present invention can enable remote measurement of alcohol concentration without interference from water vapor in the air. The concentration of water vapor in the air is usually 1% magnitude, when the remote measurement wine is driven, the integral path is usually 6-8 m, the concentration of alcohol gas (also called alcohol vapor and ethanol gas) to be measured is usually 100ppm magnitude, the integral path is only about 1m, the integral concentration of the visible alcohol is far less than the water vapor interfering in the air, but the problem can be solved, the interference of the water vapor (also called water vapor) is effectively eliminated, and the remote measurement method is also the key for realizing the remote measurement of the wine driving (alcohol concentration).

For the sake of understanding, the basic principle of the wavelength modulation technique and the calibration process will be described below.

1. Wavelength modulation:

the frequency modulation and intensity modulation of the light can be expressed as:

(frequency modulation of light)

(light intensity modulation)

V (t) is the frequency that varies over time,is the center frequency, Δ ν is the modulation depth, I₀(t) is the intensity of the laser light,is the intensity of the center frequency, i₁Is the light intensity linear modulation amplitude, ω is the angular frequency of the modulated signal, and ψ is the phase shift between the frequency modulation and the light intensity modulation.

Lambert beer's law:

I_t(t)＝I₀(t)exp[-CLα(ν)]

wherein I_t(t) is the intensity of the emitted light, I₀(t) is the intensity of the incident light, α is the absorption coefficient (in cm ^ -1), L is the propagation length of the light in the gas, and C is the mass concentration (volume fraction) of the substance of the gas. At weak absorption, there is a first order approximation:

I_t(t)＝I₀(t)·[1-CLα(v)]

further obtaining:

from the fourier expansion:

to I_tPhase-locked amplification, with a weak absorption approximation, the second harmonic (2 ω) maximum is:the first harmonic value (1 omega) at the position corresponding to the maximum value of the second harmonic isSo 2f/1f ═ H₂/i₁It can be seen that 2f/1f is independent of light intensity, so that light intensity can be eliminated (and thus is suitable for telemetry, without the need for a fixed reflectivity cooperative target, as long as a light signal diffusely reflected from a natural surface is collected), in proportion to the integrated Concentration (CL). Therefore, the integral concentration of the gas to be measured can be inverted according to 2ff1f after the calibration of the standard gas through a series of concentration gradients.

The wavelength modulation method is mainly used for the infrared or mid-infrared sensor with independent and narrow absorption peaks (the full width at half maximum of the absorption peak is 0.1cm ^ -1, and the absorption characteristics of water vapor accord with the characteristics), because most of alcohol gas is absorbed by a wide spectrum in a near-infrared region and has the interference of a plurality of water vapor absorption lines (the alcohol gas is certainly interfered by the water vapor absorption in the air when the alcohol gas is remotely measured, because the concentration C of the alcohol gas to be measured and the path L of light passing through the alcohol gas to be measured are both much smaller than the water vapor, the C is about 2 orders of magnitude different, and the L is about ten times different). That is, it is difficult to obtain the concentration of alcohol gas without the interference of water vapor, which is one of the problems to be solved by the present invention.

The drunk driving detection method is based on a wavelength modulation spectrum technology. As shown in FIG. 1, w represents the absorption (1%, 1m) curve of water vapor, and e represents the absorption (10ppm, 1m) curve of ethanol gas. It can be seen that ethanol gas absorption is severely disturbed by water vapor, and ethanol gas is a broad spectrum absorption. For two absorption peaks 1 and 2 of water, the central frequency is respectively v₁、ν₂。

Two absorption peaks 1, 2, V of water vapor₁、V₂(As mentioned above, the modulation process also modulates the light intensity in addition to the frequency modulation) is the ratio of the maximum of the second harmonic of the two absorption peaks of water to the value of the first harmonic at the maximum of this second harmonic, respectively (2f/1f value): k is more than or equal to 1

Wherein the subscript w is water, e is ethanol, and the superscripts (1) and (2) represent absorption peaks 1 and 2, respectively, and α_w1、α_w2Respectively representing water vapour at v₁V and v₂Absorption coefficient of (a) and, correspondingly, [ alpha ]_e1 and α_e2Respectively indicating alcohol vapor at v₁V and v₂The absorption coefficient of (b).

Order:

then:

V₁＝k_w1C_wL_w+k_e1C_eL_e

V₂＝k_w2C_wL_w+k_e2C_eL_e

obtaining a solution:

k_w1、k_w2obtained by varying the water vapour concentration calibration (no alcohol),by changing the alcohol concentration (there is no need to control the water vapor concentration, for the reason, reference may be made to the simulation results shown in FIG. 2, where the abscissa is the alcohol evaporation integral concentration and the ordinate isThe integrated concentration of water vapor was 1%, and the integrated path was 1m to 10m (at intervals of 1m), and it was found that the interference by water vapor was not caused). Alpha (v) in cm^-1。C_eL_eThe inversion results of (c) are water independent. From the above, it is easy to see that the water vapor does not affect the measurement of the ethanol gas concentration.

2. Calibration

Calibration requires a gas cell with a known optical path length in addition to a conventional wavelength modulation system. The specific process of calibration is as follows:

in the first step, a series of concentration gradients of water vapor are filled (to ensure that no ethanol gas exists in a gas pool), and standard lines of 2f/1f value-water vapor integral concentration at water absorption peaks 1 and 2 are obtained (straight lines y1 ═ f (x) and y2 ═ g (x)), and the slopes of the straight lines are k_w1、k_w2. In addition, in this step, alcohol gas with a certain concentration may be mixed into each concentration standard water vapor, which is equivalent to providing a positive offset for the fitted standard straight line.

Secondly, a series of ethanol with concentration gradients are filled in, and V is respectively measured₁And V₂。There are various calculation methods of (1), for example: using the slope k described above_w1、k_w2To calculate; solving through interpolation; solving the relation obtained by fitting: if V₁F (x1) and V₂G (x2), thenIt can be expressed as x1-x 2. So as to obtain C_eL_eAndis a straight line.

3. After calibration is completed, the system can be used to measure the integral concentration of alcohol gas and measure V₁And V₂And further find outThe path integral concentration C of alcohol gas can be obtained_eL_e。

In one embodiment, as shown in fig. 3, the drunk driving detection system includes: the device comprises a tunable semiconductor laser 1, a laser tail fiber 2, an optical fiber collimator 3, a semiconductor laser driving unit, a temperature control unit 4, a function signal generating unit 5, an upper computer 6, an analog-digital conversion unit 7, a photoelectric detector current-voltage conversion unit, a photoelectric detector signal amplifying unit 8, a photoelectric detector 9 and a light receiving lens 10. Of course, the structural composition of the drunk driving detection system of the present invention is not limited thereto, and those skilled in the art can appropriately adjust the structure as needed.

The laser 1 is connected with an optical fiber collimator 3 through a laser tail fiber 2, the laser 1 is used for emitting laser and transmitting the laser to the optical fiber collimator 3 through the laser tail fiber 2, and the optical fiber collimator 3 is used for collimating the laser output by the laser 1 and then sending the laser to a cab to be detected;

the upper computer 6 is used for controlling the function signal generating unit 5 to generate function signals; the semiconductor laser driving unit and the temperature control unit 4 are used for receiving the function signal generated by the function signal generating unit 5 and driving the laser 1 to emit laser;

the light receiving lens 10 is used for receiving light transmitted back through the windshield after the laser emitted into the cab to be detected is subjected to diffuse reflection;

the photoelectric detector 9 is used for detecting the light emitted by the light receiving lens and coming back through the windshield after the laser emitted into the cab to be detected is subjected to diffuse reflection;

the photoelectric detector current-voltage conversion unit and the signal amplification unit 8 are used for receiving the current signal output by the photoelectric detector 9, converting the current signal into a voltage signal, and outputting the voltage signal after amplification;

the analog-digital conversion unit 7 is used for receiving the amplified signals output by the photoelectric detector current-voltage conversion unit and the signal amplification unit 8, performing analog-digital conversion, and converting the analog signals into digital signals and outputting the digital signals;

the upper computer 6 (which includes a lock-in amplifier (such as a digital lock-in amplifier) or other demodulation devices) is used for receiving the digital signal output by the analog-digital conversion unit 7, generating a first harmonic and a second harmonic, and processing the first harmonic and the second harmonic to obtain the integrated concentration of the alcohol path in the cab to be detected.

And the drunk driving detection system quantitatively determines the alcohol path integral concentration in the cab to be detected by using the light reflected by the diffuse reflection.

The present invention has been described in detail with reference to the accompanying drawings. From the above description, those skilled in the art should clearly recognize the present invention.

It is to be noted that, in the attached drawings or in the description, the implementation modes not shown or described are all the modes known by the ordinary skilled person in the field of technology, and are not described in detail. In addition, the above definitions of the respective elements are not limited to the specific structures, shapes or modes mentioned in the embodiments, and those skilled in the art may easily modify or replace them.

Of course, the present invention may also include other parts according to actual needs, and the details are not described herein since they are not related to the innovation of the present invention.

Similarly, it should be appreciated that in the foregoing description of exemplary embodiments of the invention, various features of the invention are sometimes grouped together in a single embodiment, figure, or description thereof for the purpose of streamlining the invention and aiding in the understanding of one or more of the various inventive aspects. However, the method of the invention should not be construed to reflect the intent: that the invention as claimed requires more features than are expressly recited in each claim. Rather, as the following claims reflect, inventive aspects lie in less than all features of a single foregoing inventive embodiment. Thus, the claims following the detailed description are hereby expressly incorporated into this detailed description, with each claim standing on its own as a separate embodiment of this invention.

Furthermore, the use of ordinal numbers such as "first," "second," "third," etc., in the specification and claims to modify a corresponding element is not intended to imply any ordinal numbers for the element, nor the order in which an element is sequenced or methods of manufacture, but are used to distinguish one element having a certain name from another element having a same name.

Further, in the drawings or description, the same drawing reference numerals are used for similar or identical parts. Features of the embodiments illustrated in the description may be freely combined to form new embodiments without conflict, and each claim may be individually referred to as an embodiment or features of the claims may be combined to form a new embodiment, and in the drawings, the shape or thickness of the embodiment may be enlarged and simplified or conveniently indicated. Further, elements or implementations not shown or described in the drawings are of a form known to those of ordinary skill in the art. Additionally, while exemplifications of parameters including particular values may be provided herein, it is to be understood that the parameters need not be exactly equal to the respective values, but may be approximated to the respective values within acceptable error margins or design constraints.

Unless a technical obstacle or contradiction exists, the above-described various embodiments of the present invention may be freely combined to form further embodiments, which are within the scope of the present invention.

Although the present invention has been described in connection with the accompanying drawings, the embodiments disclosed in the drawings are intended to be illustrative of preferred embodiments of the present invention and should not be construed as limiting the invention. The dimensional proportions in the figures are merely schematic and are not to be understood as limiting the invention.

Although a few embodiments of the present general inventive concept have been shown and described, it would be appreciated by those skilled in the art that changes may be made in these embodiments without departing from the principles and spirit of the general inventive concept, the scope of which is defined in the claims and their equivalents.

The above description is only for the purpose of illustrating the preferred embodiments of the present invention and is not to be construed as limiting the invention, and any modifications, equivalents, improvements and the like that fall within the spirit and principle of the present invention are intended to be included therein.