Quartz tuning fork gas sensing device based on diamond-like carbon coating enhancement

Abstract

The invention relates to the field of gas detection, in particular to a diamond-like coating enhanced quartz tuning fork gas sensing device which comprises a laser signal transmitting unit, a light absorption cell, a lens, a quartz tuning fork and an electric signal acquisition unit which are sequentially connected, and the surface of the quartz tuning fork is coated with a diamond-like coating; a target optical signal generated by the laser signal transmitting unit is transmitted to the optical absorption cell; target gas to be detected is contained in the light absorption cell, and the light signal interacts with the target gas in the light absorption cell; and the lens focuses light emitted from the light absorption cell to the surface of the quartz tuning fork of which the surface is coated with a diamond-like coating. Compared with the prior art, the device can sensitively capture fine changes caused by trace gas and convert the fine changes into obvious electric signals, the linear relation between the electric signals and the gas concentration is good, and high-precision measurement of low-concentration gas is achieved.

Description

Technical Field

[0001] The invention relates to the field of transformer gas alarm free gas detection, in particular to a quartz tuning fork gas sensor device based on diamond-like carbon coating enhancement. Background Art

[0002] A gas relay (also known as a gas relay) is a protective device used in transformers. It is installed in the pipeline between the oil storage cabinet and the oil tank of the transformer. When the internal fault of the transformer causes the oil to decompose and produce gas or causes oil flow to surge, the contacts of the gas relay are activated, the specified control circuit is connected, and a signal alarm is issued in time (light gas) or the protection element is activated to automatically cut off the transformer (heavy gas). When the gas relay has a light gas warning or heavy gas removal action, it is necessary to analyze the free gas in the gas relay to determine whether the transformer has failed and the extent of the failure. Accurate gas sensing technology helps to realize the condition monitoring and preventive maintenance of the transformer. With the help of continuous monitoring of the gas in the gas relay, potential faults can be detected in advance, and maintenance can be arranged before the fault develops into a serious accident, reducing the probability of sudden equipment failure, reducing maintenance costs, extending the service life of the transformer, and ensuring the long-term stable operation of the power system.

[0003] For example, Chinese patent application CN118549350A discloses a quartz tuning fork gas detection system based on a perovskite composite material coating, which uses the coupling of the photothermoelectric effect generated by laser irradiation of the perovskite composite material coating and the photothermoelastic effect of a quartz tuning fork to detect gas. From the perspective of material properties, the organic-inorganic hybrid perovskite component in the perovskite composite material coating is more sensitive to environmental factors. For example, changes in humidity and temperature can affect its performance. In a high humidity environment, the organic-inorganic hybrid perovskite will decompose, resulting in the destruction of the coating structure, thereby affecting the coupling effect of the photothermoelectric effect and the photothermoelastic effect, making the detection signal unstable, and ultimately affecting the accuracy and reliability of the detection.

[0004] The Herriot gas cell used in the perovskite composite coating solution requires precise temperature control. Although the setting of its insulation layer helps to maintain the internal temperature stability to a certain extent, it is still difficult to ensure that the temperature in the gas cell is constant within the ideal detection range in extreme temperature environments. Once the temperature fluctuates greatly, it will not only affect the thermoelastic effect of the gas molecules, but may also cause the performance of the perovskite composite coating to change, reducing the detection accuracy. In addition, the perovskite composite coating relies on the fitting equation of the second harmonic amplitude and concentration change to calculate the concentration of the gas to be measured. If there are interference factors in the actual detection process, such as background noise, cross-interference from other gases, etc., it may cause the accuracy of the fitting equation to decrease, thereby affecting the detection accuracy.

[0005] In summary, perovskite composite coatings are sensitive to environmental factors, and their applications in complex environments are subject to certain restrictions. They can only be used in specific environments. In addition, the detection band is limited, and the wavelength cannot be flexibly adjusted to achieve multi-band detection. When dealing with the detection of gases with various different absorption characteristics, there are limitations and it cannot meet complex and diverse detection needs. Summary of the invention

[0006] The purpose of the present invention is to overcome the defects of the prior art such as limited detection band, high sensitivity to environmental factors and interference during the detection process, and to provide a quartz tuning fork gas sensor device based on diamond-like carbon coating enhancement.

[0007] The purpose of the present invention can be achieved by the following technical solutions:

[0008] A quartz tuning fork gas sensor device based on diamond-like coating enhancement, comprising a laser signal emitting unit, a light absorption cell, a lens, a quartz tuning fork and an electrical signal acquisition unit connected in sequence, wherein the surface of the quartz tuning fork is coated with a diamond-like coating;

[0009] The target light signal generated by the laser signal emitting unit is transmitted to the light absorption cell;

[0010] The light absorption cell contains a target gas to be detected, and the light signal interacts with the target gas in the light absorption cell;

[0011] The lens focuses the light emitted from the light absorption cell onto the surface of the quartz tuning fork coated with a diamond-like coating.

[0012] As a preferred technical solution, the laser signal emitting unit includes a laser, an optical modulator, a power amplifier, an optical filter, an optical isolator and a collimator which are connected in sequence through optical fibers. The optical centers of each unit are on the same horizontal line, and the light absorption pool is opposite to the collimator.

[0013] As a preferred technical solution, the optical modulator modulates the characteristics of the laser output by the laser to change the energy and change law of the light irradiated to the surface of the quartz tuning fork;

[0014] The optical filter screens the wavelength of the optical signal so that the light entering the optical absorption cell matches the characteristic absorption peak of the target gas.

[0015] As a preferred technical solution, an anti-reflection coating is provided in the light absorption pool, and two reflectors are symmetrically installed on the inner walls on both sides of the light absorption pool, and the center height of the reflectors is consistent with the center axis height of the light absorption pool.

[0016] As a preferred technical solution, the distance between the two reflectors is set between 0.8-0.95 of the length of the light absorption cell.

[0017] As a preferred technical solution, the light absorption cell is symmetrically provided with an air inlet and an air outlet; the target gas to be detected enters the light absorption cell 7 through the air inlet, and the detected gas is discharged from the air outlet.

[0018] As a preferred technical solution, the lens is installed on the light emitting side of the light absorption cell, and the center of the lens is on the same horizontal line as the central axis of the light absorption cell.

[0019] As a preferred technical solution, the distance between the lens and the light absorption cell is:

[0020] d=D / (1+cosθ)

[0021] Wherein, D is the distance from the quartz tuning fork to the exit surface of the light absorption cell; θ is the divergence angle of the light emitted from the light absorption cell.

[0022] As a preferred technical solution, the electrical signal acquisition unit includes a plurality of

[0023] A transimpedance amplifier amplifies the electrical signal generated by the quartz tuning fork;

[0024] The phase-locked amplifier selectively amplifies and phase-sensitively detects the signal of a specific frequency output by the transimpedance amplifier, and extracts the weak signal related to the target gas;

[0025] The computer receives and processes the signal from the lock-in amplifier, and analyzes, stores and displays the gas detection data.

[0026] As a preferred technical solution, the sensing device further includes a laser driver, which is connected to the laser and computer signals and is used to adjust the laser output parameters of the laser according to detection requirements.

[0027] Compared with the prior art, the present invention has the following beneficial effects:

[0028] 1) The present invention uses diamond-like coating for quartz tuning fork gas sensor device. Diamond-like coating can efficiently absorb modulated light energy, so that the quartz tuning fork has a significant thermal deposition response to weak light intensity changes, thereby inducing a thermoelastic effect, causing the quartz tuning fork to deform. Due to the piezoelectric effect of the quartz tuning fork itself, this deformation is converted into an electrical signal, realizing the conversion from light energy to mechanical energy and then to electrical energy, thereby detecting gas. It can sensitively capture subtle changes caused by trace gases, convert them into obvious electrical signals, and then realize the detection of gas. The present invention uses diamond-like coating to produce a significant thermal deposition response to weak light intensity changes, so as to sensitively capture subtle changes caused by trace gases.

[0029] 2) The present invention optimizes the settings of the reflector and the lens so that the laser signal incident on the light absorption cell and the laser signal acting on the quartz tuning fork are on the same horizontal line, and the sensitivity and reliability of gas detection are improved by focusing the laser signal.

[0030] 3) The diamond-like coating-enhanced quartz tuning fork gas sensor device provided by the present invention has relatively low sensitivity to factors such as ambient temperature due to its high hardness, wear resistance, and good chemical stability, and has stronger environmental adaptability. The diamond-like coating can also effectively protect the quartz tuning fork, reduce the impact of environmental factors such as mechanical vibration and electromagnetic interference, reduce measurement errors and performance drift, and ensure stable operation of the device and accurate signal output.

[0031] 4) The diamond-like coating enhanced quartz tuning fork gas sensor device provided by the present invention has good thermal conductivity of the diamond-like coating, which enables the device to respond quickly and react quickly to changes in gas concentration. At the same time, by flexibly adjusting parameters such as the wavelength of light, the device can detect target gases in a variety of industries and environmental monitoring and has a wide range of applications. BRIEF DESCRIPTION OF THE DRAWINGS

[0032] Figure 1 A schematic diagram of a diamond-like carbon coating-enhanced quartz tuning fork gas sensor device provided in an embodiment of the present invention;

[0033] Figure 2 is a gas detection graph of a prior art coating;

[0034] Figure 3 This is a detection curve diagram of the quartz tuning fork gas sensor device enhanced by the diamond-like coating of the present application;

[0035] The numbers in the figure are as follows: 1. Laser; 2. Light modulator; 3. Power amplifier; 4. Filter; 5. Optical isolator; 6. Collimator; 7. Light absorption cell; 8. Reflector; 9. Air inlet; 10. Exhaust port; 11. Lens; 12. Quartz tuning fork; 13. Transimpedance amplifier; 14. Phase-locked amplifier; 15. Computer; 16. Laser driver. DETAILED DESCRIPTION

[0036] The present invention is described in detail below in conjunction with the accompanying drawings and specific embodiments. This embodiment is implemented based on the technical solution of the present invention, and provides a detailed implementation method and specific operation process, but the protection scope of the present invention is not limited to the following embodiments.

[0037] Example 1

[0038] like Figure 1The figure shows a schematic structural diagram of a diamond-like coating enhanced quartz tuning fork gas sensor device provided in an embodiment of the present invention. The diamond-like coating enhanced quartz tuning fork gas sensor device provided in the present invention includes: a laser 1, an optical modulator 2, a power amplifier 3, an optical filter 4, an optical isolator 5, a collimator 6, a light absorption cell 7, a reflector 8, an air inlet 9, an exhaust port 10, a lens 11, a quartz tuning fork 12, a transimpedance amplifier 13, a phase-locked amplifier 14, a computer 15, and a laser driver 16.

[0039] The positions of the above-mentioned units are arranged as follows: the laser 1, the optical modulator 2, the power amplifier 3, the optical filter 4, the optical isolator 5, and the collimator 6 are connected in sequence through optical fibers, and the optical centers of the units are on the same horizontal line; the light absorption cell 7 is opposite to the collimator 6; the two reflectors 8 are relatively installed in the light absorption cell 7; the air inlet 9 and the exhaust port 10 are symmetrically installed on the light absorption cell 7; the lens 11 and the quartz tuning fork 12 are installed in sequence to keep the same optical center axis as the light absorption cell 7; the transimpedance amplifier 13, the phase-locked amplifier 14, and the computer 15 are connected in sequence through data lines; the computer 15 is also connected to the laser driver 16.

[0040] Laser 1 provides starting energy for the thermoelastic effect by emitting intensity-modulated light. It can also accurately detect specific gases by adjusting the wavelength and control the signal intensity by adjusting parameters such as the intensity of the output light and the modulation frequency to ensure that a suitable and stable signal can be output in different gas concentration environments for subsequent processing and analysis.

[0041] In this embodiment, the laser 1 is preferably an external cavity quantum cascade laser, which has good wavelength tunability, can output high power, has high precision and stability, can enhance the photothermoelastic effect, realize the detection of multiple gases and ensure the reliability of detection.

[0042] The optical modulator 2 precisely controls the intensity, frequency and other characteristics of the light output by the laser 1, thereby changing the energy and variation law of the light irradiated to the surface of the quartz tuning fork 12, and further controlling the degree of heat deposition caused by the thermoelastic effect and the intensity of the generated electrical signal.

[0043] In this embodiment, the optical modulator 2 is preferably a lithium niobate (LiNbO3) electro-optic modulator, which has the characteristics of high-speed modulation, low insertion loss, wide wavelength application range and high extinction ratio, and can accurately and efficiently modulate the intensity, phase and other parameters of the output light of the laser 1.

[0044] The power amplifier 3 amplifies the power of the laser signal modulated by the optical modulator 2, and provides a light signal of sufficient intensity for subsequent units such as the optical filter 4, the optical isolator 5, and the collimator 6, so as to ensure that the light signal has sufficient energy to drive during the entire process of being transmitted to the light absorption cell, interacting with the gas therein, and finally being received by the quartz tuning fork and converted into an electrical signal, thereby ensuring that the device can stably and accurately detect the gas concentration.

[0045] In this embodiment, the power amplifier 3 is preferably a high-gain, low-noise, wide-band semiconductor optical power amplifier, which can effectively amplify the optical signal power while reducing signal noise interference. The wide-band characteristic can adapt to optical signals of different wavelengths and provide the device with sufficiently strong and high-quality optical signals.

[0046] The optical filter 4 selects light of a specific wavelength range from the optical signal amplified by the power amplifier and removes other stray light to ensure that the light entering the optical absorption cell is pure and effective light that matches the characteristic absorption peak of the target gas, so as to improve the accuracy and stability of the device in detecting the target gas.

[0047] In this embodiment, the filter 4 is preferably a tunable fiber Fabry-Perot (FP) filter, which has the characteristics of narrow bandwidth filtering, wavelength tunability, high resolution and low insertion loss. It can accurately filter out light in the target wavelength range, effectively remove stray light, and can be flexibly adjusted according to the optical wavelength required for different gas detection, thereby improving the accuracy of detection.

[0048] The optical isolator 5 ensures that the optical signal is transmitted unidirectionally in a specific direction, prevents reflected light, stray light, etc. from entering the previous optical path in reverse, prevents these interference lights from affecting the normal operation of devices such as lasers and power amplifiers, ensures the stability and reliability of the optical path system of the device, and thus improves the accuracy of gas detection.

[0049] In this embodiment, the optical isolator 5 is preferably a Faraday rotation optical isolator, which has the characteristics of high isolation, wide wavelength range, low insertion loss and high stability. It can effectively prevent reverse light interference, ensure unidirectional and stable transmission of optical signals, and adapt to the optical path system in the device, which helps to stabilize the operation of the optical path during the detection process.

[0050] The collimator 6 converts the divergent light into a parallel light beam, improves the directionality and focusing of the light, enables the light to be irradiated onto the target gas more accurately, improves the interaction efficiency between light and gas, and enhances the performance of the entire detection system.

[0051] In this embodiment, the collimator 6 is preferably a fiber collimator, which has the characteristics of high-precision beam collimation, low insertion loss, wide wavelength adaptability and compact structure. It can efficiently collimate the light output by the optical fiber into a parallel beam, ensure that the light propagates in the appropriate direction in the optical path of the device, and ensure the effective transmission and precise alignment of light during the detection process.

[0052] The light absorption cell 7 provides a stable accommodation space for the gas to be detected and a stable and efficient gas-light interaction environment for the photothermoelastic spectroscopy technology, thereby laying a foundation for the subsequent process of the quartz tuning fork converting the light signal into an electrical signal based on the thermoelastic effect, so as to achieve accurate detection of the gas.

[0053] In this embodiment, the light absorption cell 7 is preferably a light absorption cell with an anti-reflection coating, optimized internal optical path and good sealing, which can effectively reduce light reflection loss, increase the effective action path of light and gas, and ensure that the gas sample fully interacts with light in a stable environment, which is beneficial to improving the efficiency of phosgene interaction during gas detection, thereby improving detection accuracy.

[0054] The reflector 8, which is arranged opposite to each other, reflects the light processed by the filter 4, the optical isolator 5 and the collimator 6 for multiple times, prolongs the propagation path of the light in the pool 7, enhances the interaction between the light and the gas molecules, and makes the gas molecules produce a thermoelastic effect after absorbing the light energy. In this embodiment, the reflector 8 is preferably a reflector with a concave surface on the opposite side, which can realize the maximum utilization of light energy and improve the reliability of gas detection.

[0055] Specifically, the reflectors 8 are symmetrically installed on the inner walls on both sides of the light absorption pool 7, and the center height of the reflectors 8 is consistent with the center axis height of the light absorption pool 7. The distance between the reflectors 8 is determined according to the length of the light absorption pool 7 and the detection requirements. If the length of the light absorption pool 7 is L, in order to ensure that the laser can be fully reflected in the light absorption pool 7 and enhance the interaction with the gas molecules, the distance between the reflectors 8 can be set to be close to the length L of the light absorption pool, but the energy loss of the laser in the reflection process and the installation space and other factors must be taken into account, and the value is between (0.8-0.95) L. For example, when the length of the light absorption pool 7 is 50 cm, the distance between the reflectors 8 can be set to 45 cm. A shorter distance may result in insufficient laser reflection times and insufficient interaction between light and gas; while a too long distance may increase laser transmission loss, reduce light intensity, and affect the detection effect.

[0056] The air inlet 9 is used for the target gas to enter the light absorption cell 7 and fully interact with the detection light signal; the air outlet 10 is used for discharging the detected gas.

[0057] The lens 11 focuses the light passing through the light absorption cell 7 and adjusts the propagation direction of the light, thereby improving the efficiency of light energy utilization and ensuring that the light accurately acts on the quartz tuning fork 12 to enhance the photothermoelastic effect and improve the sensitivity and accuracy of gas detection. In this embodiment, the lens 11 is preferably a convex lens.

[0058] Specifically, the lens 11 is installed on the light-emitting side of the light absorption pool 7, and its center is on the same horizontal line as the central axis of the light absorption pool 7, and the distance between the lens 11 and the light absorption pool 7 should ensure that the light emitted from the light absorption pool 7 is focused by the lens 11, and the focus falls on the surface of the quartz tuning fork 12. The position of the lens 11 is determined based on the divergence angle of the light emitted from the light absorption pool 7 and the position of the quartz tuning fork 12. Assuming that the divergence angle of the light emitted from the light absorption pool is θ, and the distance from the quartz tuning fork 12 to the exit surface of the light absorption pool 7 is D, according to the focusing principle of the lens 11, the distance d between the lens 11 and the light absorption pool 7 can be calculated by the formula d=D / (1+cosθ). For example, when the divergence angle θ is 30° and the distance D from the quartz tuning fork 12 to the exit surface of the light absorption pool 7 is 20 cm, the distance d between the lens 11 and the light absorption pool 7 is approximately 17.3 cm.

[0059] The present invention optimizes the settings of the reflector 8 and the lens 11 so that the laser signal incident on the light absorption cell 7 and the laser signal acting on the quartz tuning fork 12 are on the same horizontal line, and the sensitivity and reliability of gas detection are improved by focusing the laser signal.

[0060] When the light focused and directed by the lens is irradiated onto the surface of the quartz tuning fork 12, thermal deposition and thermoelastic effects will occur due to the diamond-like coating on the surface of the quartz tuning fork, causing the quartz tuning fork to deform. The piezoelectric effect of the quartz tuning fork itself will convert the deformation caused by the photo-induced thermoelastic effect into an electrical signal, thereby realizing the conversion from light energy to mechanical energy and then to electrical energy.

[0061] The transimpedance amplifier 13 amplifies the weak electrical signal generated by the quartz tuning fork 12 due to the photothermoelastic effect and converts it into a signal with a suitable amplitude so that the subsequent phase-locked amplifier can perform more accurate signal processing and analysis, thereby providing strong signal support for the ultimate accurate detection of gas.

[0062] The phase-locked amplifier 14 further processes the signal output by the transimpedance amplifier, and effectively extracts the weak signal related to the target gas by selectively amplifying and phase-sensitively detecting the signal of a specific frequency, and suppresses noise and interference, thereby improving the precision and accuracy of gas detection.

[0063] The computer 15 is connected to the phase-locked amplifier 14, receives and processes the signal from the phase-locked amplifier 14, analyzes, stores and displays the gas detection data through corresponding software and algorithms, realizes the automatic control of the gas detection process, data processing and result presentation, and assists the user to accurately determine the type and concentration of the gas; it is connected to the laser driver 16 to control and adjust the working parameters of the laser 1, and realize the automatic control of the detection system.

[0064] The laser driver 16 adjusts the power, wavelength and other parameters of the laser 1 according to different detection requirements, thereby optimizing the detection performance of the system and ensuring that the entire detection system operates efficiently and accurately.

[0065] Example 2

[0066] This embodiment provides a specific application implementation of the diamond-like carbon coating enhanced quartz tuning fork gas sensor device described in the above embodiment:

[0067] Computer 15 controls laser 1 to generate laser of specific wavelength through laser driver 16. Laser passes through optical modulator 2 in sequence to modulate the intensity, frequency or phase of light; then it is amplified by power amplifier 3 to meet the detection requirements; then it is filtered out by filter 4 to filter out the light of target wavelength range and remove stray light; then optical isolator 5 ensures unidirectional transmission of optical signal to prevent interference of reflected light; finally, collimator 6 collimates the light into parallel light so that it can enter light absorption cell 7 efficiently.

[0068] The collimated parallel light enters the light absorption cell 7, and the reflectors 8 installed relatively in the cell reflect the light multiple times, extending the propagation path of the light in the cell and enhancing the interaction between the light and the gas to be detected entering from the air inlet 9. The gas molecules produce a thermoelastic effect after absorbing the light energy. The light emitted from the light absorption cell 7 is focused by the lens 11 onto the quartz tuning fork 12 coated with a diamond-like coating on the surface. The photothermoelastic effect causes the quartz tuning fork 12 to deform, and based on its piezoelectric effect, the deformation is converted into a weak electrical signal. The weak electrical signal is preliminarily amplified by the transimpedance amplifier 13 and converted into an electrical signal with a suitable amplitude. The signal output by the transimpedance amplifier 13 is transmitted to the phase-locked amplifier 14, and the weak signal related to the target gas is extracted and noise interference is suppressed through the selective amplification and phase-sensitive detection of the specific frequency signal. Finally, the processed signal is transmitted to the computer 15, and the gas detection result is obtained after analysis, storage and display, and the detected gas is discharged from the exhaust port 10.

[0069] In this embodiment, the solution proposed by the present invention is experimentally compared with the existing perovskite composite material coating solution. Figure 2 Shown is a gas detection graph of a prior art perovskite composite material coating solution; Figure 3This is a detection curve diagram of the diamond-like coating enhanced quartz tuning fork gas sensor device of the present application. It can be seen that the diamond-like coating enhanced quartz tuning fork gas sensor device proposed in the present application is superior to the existing coating solution in terms of detection accuracy and anti-interference performance.

[0070] The preferred specific embodiments of the present invention are described in detail above. It should be understood that a person skilled in the art can make many modifications and changes based on the concept of the present invention without creative work. Therefore, any technical solution that can be obtained by a person skilled in the art through logical analysis, reasoning or limited experiments based on the concept of the present invention on the basis of the prior art should be within the scope of protection determined by the claims.

Claims

1. A quartz tuning fork gas sensor device based on diamond-like carbon coating enhancement, comprising a laser signal emitting unit, a light absorption cell (7), a lens (11), a quartz tuning fork (12) and an electrical signal acquisition unit connected in sequence, characterized in that: The surface of the quartz tuning fork (12) is coated with a diamond-like coating; The target light signal generated by the laser signal emitting unit is transmitted to the light absorption pool (7); The light absorption cell (7) contains a target gas to be detected, and the light signal interacts with the target gas in the light absorption cell (7); The lens (11) focuses the light emitted from the light absorption cell (7) onto the surface of a quartz tuning fork (12) coated with a diamond-like coating.

2. A quartz tuning fork gas sensor device based on diamond-like carbon coating enhancement according to claim 1, characterized in that: The laser signal transmitting unit comprises a laser (1), an optical modulator (2), a power amplifier (3), an optical filter (4), an optical isolator (5) and a collimator (6) which are sequentially connected via optical fibers, the optical centers of each unit are on the same horizontal line, and the light absorption pool (7) is opposite to the collimator (6).

3. A quartz tuning fork gas sensor device based on diamond-like carbon coating enhancement according to claim 2, characterized in that: The optical modulator (2) modulates the characteristics of the laser output by the laser (1) to change the energy and change law of the light irradiated onto the surface of the quartz tuning fork (12); The optical filter (4) screens the wavelength of the optical signal so that the light entering the optical absorption cell (7) matches the characteristic absorption peak of the target gas.

4. The diamond-like carbon coating-enhanced quartz tuning fork gas sensor device according to claim 1, characterized in that: The light absorption pool (7) is provided with an anti-reflection coating, and two reflectors (8) are symmetrically mounted on the inner walls on both sides of the light absorption pool (7), wherein the center height of the reflectors (8) is consistent with the center axis height of the light absorption pool (7).

5. The diamond-like carbon coating-enhanced quartz tuning fork gas sensor device according to claim 4, characterized in that: The distance between the two reflecting mirrors (8) is set between 0.8 and 0.95 of the length of the light absorption cell.

6. The diamond-like carbon coating-enhanced quartz tuning fork gas sensor device according to claim 1, characterized in that: An air inlet (9) and an air outlet (10) are symmetrically mounted on the light absorption cell (7); the target gas to be detected enters the light absorption cell 7 through the air inlet (9), and the detected gas is discharged from the air outlet (10).

7. The diamond-like carbon coating-enhanced quartz tuning fork gas sensor device according to claim 1, characterized in that: The lens (11) is installed on the light emitting side of the light absorption pool (7), and the center of the lens (11) and the center axis of the light absorption pool (7) are on the same horizontal line.

8. The diamond-like carbon coating-enhanced quartz tuning fork gas sensor device according to claim 7, characterized in that: The distance between the lens (11) and the light absorption pool (7) is: d=D / (1+cosθ) Wherein, D is the distance from the quartz tuning fork (12) to the exit surface of the light absorption pool (7); θ is the divergence angle of the exit light of the light absorption pool.

9. The diamond-like carbon coating-enhanced quartz tuning fork gas sensor device according to claim 1, characterized in that: The electrical signal acquisition unit includes a plurality of A transimpedance amplifier (13) amplifies the electrical signal generated by the quartz tuning fork (12); A phase-locked amplifier (14) selectively amplifies and phase-sensitively detects a signal of a specific frequency output by the transimpedance amplifier (13) to extract a weak signal related to the target gas; The computer (15) receives and processes the signal from the phase-locked amplifier (14), and analyzes, stores and displays the gas detection data.

10. The diamond-like carbon coating-enhanced quartz tuning fork gas sensor device according to claim 9, characterized in that: The sensing device further comprises a laser driver (16), which is connected to the laser (1) and the computer (15) by signal and is used to adjust the laser output parameters of the laser (1) according to detection requirements.

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