CN119086492A - Frequency division multiplexing multi-component compact laser gas detection module and detection system - Google Patents
Frequency division multiplexing multi-component compact laser gas detection module and detection system Download PDFInfo
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- CN119086492A CN119086492A CN202411288257.1A CN202411288257A CN119086492A CN 119086492 A CN119086492 A CN 119086492A CN 202411288257 A CN202411288257 A CN 202411288257A CN 119086492 A CN119086492 A CN 119086492A
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Abstract
The invention relates to a frequency division multiplexing type multi-component compact laser gas detection module and a detection system, wherein the laser gas detection module comprises a shell, a first optical module, a gas baffle, a laser group and a first photoelectric sensor; the shell is provided with a gas diffusion film, a closed air cavity is formed by the gas baffle, the gas diffusion film and the first optical module, the laser unit is used for sending laser signals into the closed air cavity, and the first photoelectric sensor is used for receiving reflection signals of the laser signals sent by the laser unit after being folded by the first optical module, converting the reflection signals into electric signals and outputting the electric signals. The invention effectively realizes optical path multiplication through the deflection of the laser signals in the closed air cavity, realizes the frequency division multiplexing detection of various gases with different concentrations through simultaneously emitting the laser signals with different frequencies, and is convenient for the connection with an external system and easy to process and calibrate because the emitting end and the receiving end of the laser signals are positioned on the same side.
Description
Technical Field
The invention relates to the technical field of gas detectors, in particular to a frequency division multiplexing type multi-component compact laser gas detection module and a detection system.
Background
Many flammable, explosive and toxic gases are colorless, and once the dangerous gases leak, the dangerous gases can threaten industrial production, energy exploitation and transportation, atmospheric environment and the like if not found in time. For example, in the coal mining process, the underground gas environment of the coal mine is complex and changeable, carbon monoxide, methane, hydrogen sulfide and the like are main gases for causing explosion and poisoning accidents, the life and property safety of human bodies are threatened, acetylene and the like are important process control objects in many chemical industry related industries, and carbon dioxide is main greenhouse gas which can bring about increasingly serious environmental problems if not effectively monitored and controlled. Thus, continuous monitoring of such hazardous gas concentrations is essential for personnel and equipment safety as well as environmental safety.
In recent years, the TDLAS technology is widely applied in the field of gas detection, and compared with the traditional gas concentration detection method, the TDLAS technology has the advantages of high resolution, strong selectivity, high response speed, long service life, no poisoning problem and the like. The principle is that a laser with a narrow linewidth is tuned to scan a specific gas absorption peak, after a light beam with a specific wavelength is absorbed by a gas to be detected, a signal acquisition and processing unit converts an optical signal into an electric signal, and finally the concentration of the gas to be detected is inverted according to the intensity of the received signal.
The existing laser gas detection structure has a plurality of reflecting components, and the defects of complex structure, inconvenience for processing and calibration and single detection gas generally exist.
Disclosure of Invention
The invention aims to solve the technical problems that in the prior art, reflecting parts of a laser gas detection structure are numerous, the structure is complex, the processing and the calibration are not facilitated, and the detection gas is single, and provides a frequency division multiplexing type multi-component compact laser gas detection module and a detection system.
In order to solve the technical problems, the technical scheme of the invention is as follows:
A frequency division multiplexing type multi-component compact laser gas detection module comprises a shell, a first optical module, a gas baffle, a laser set and a first photoelectric sensor;
The shell is provided with a gas diffusion film;
The first optical module comprises a compound mirror and a plurality of total reflectors, wherein the compound mirror comprises a first total reflector and a semi-transparent semi-reflective mirror, and different reflectivities and transmittances of the compound mirror are realized at different positions by changing surface coatings;
the gas baffle plate is arranged in the shell, and the gas baffle plate, the gas diffusion membrane and the first optical module form a closed air cavity;
the laser group is used for sending out laser signals into the closed air cavity;
the first photoelectric sensor is used for receiving a reflected signal of a laser signal sent by the laser group after being folded by the first optical module, converting the reflected signal into an electric signal and outputting the electric signal;
The laser gas detection module further comprises a reference light path, wherein the reference light path comprises a second optical module, a reference air chamber and a second photoelectric sensor, laser signals sent by the laser group are divided into two paths after passing through the half mirror, one path of the laser signals continues to be folded in the closed air chamber, and the other path of the laser signals enters the reference air chamber after being folded by the second optical module;
The mixed reference gas is introduced into the reference gas chamber, the laser signal is fully absorbed by the mixed reference gas after being injected into the reference gas chamber, and the output laser signal is converted into an electric signal by the second photoelectric sensor and then is used for the reference signal of gas peak searching and concentration inversion, so that the frequency division multiplexing detection of the gas is realized.
In the technical scheme, the plurality of total reflectors comprise a second total reflector, a third total reflector and a fourth total reflector, wherein the second total reflector and the compound reflector are mutually perpendicular to one another and are arranged on the inner wall of one side of the shell, the third total reflector and the fourth total reflector are mutually perpendicular to one another and are arranged on the inner wall of the other side of the shell, the third total reflector and the compound reflector are arranged in parallel, and the second total reflector and the fourth total reflector are arranged in parallel.
The second optical module comprises a fifth total reflection mirror and a sixth total reflection mirror, wherein the fifth total reflection mirror is used for turning laser signals transmitted through the half-transmission half-reflection mirror, and the sixth total reflection mirror is perpendicular to the fifth total reflection mirror and used for receiving the laser signals turned through the fifth total reflection mirror and turning the received laser signals into the reference air chamber.
In the above technical scheme, the laser group is a near infrared laser and is electrically connected with the laser driving unit, and the laser driving unit sends a laser driving signal to the laser group so that the laser group sends a modulated laser signal according to the corresponding driving signal.
In the technical scheme, the laser driving unit comprises a low-frequency scanning signal generating unit, a high-frequency modulating signal generating unit, a signal superposition unit and a temperature control unit, wherein the low-frequency scanning signal generating unit is used for generating a low-frequency scanning signal, the high-frequency modulating signal generating unit is used for generating a high-frequency modulating signal, the signal superposition unit is used for superposing the low-frequency scanning signal and the high-frequency modulating signal into a modulating laser signal, and the temperature control unit is used for adjusting the temperature of the modulating laser signal and enabling the modulating laser signal to be at a working temperature.
In the technical scheme, the laser gas detection module further comprises a collimating lens, wherein the collimating lens is arranged on an optical path before a laser signal enters the closed air cavity and is used for collimating the laser signal sent by the laser group, and the laser group is arranged at the focal position of the collimating lens.
In the technical scheme, the laser gas detection module further comprises a second converging lens, wherein the second converging lens is arranged between the second optical module on the reference optical path and the reference air chamber and used for focusing the laser signals folded by the second optical module to a second photoelectric sensor, and the second photoelectric sensor is arranged at the focal position of the second converging lens.
In the technical scheme, the laser gas detection module further comprises a first focusing lens, wherein the first focusing lens is arranged at the outlet of the closed air cavity and used for focusing the reflected signals after being folded by the first optical module to the first photoelectric sensor, and the first photoelectric sensor is arranged at the focal point of the first focusing lens.
A frequency division multiplexing type multi-component compact laser gas detection system comprises a laser gas detection module, a phase-locked amplifying module and an external processor unit;
The laser gas detection module is the laser gas detection module;
the phase-locked amplifying module is respectively and electrically connected with the first photoelectric sensor and the second photoelectric sensor and is used for processing electric signals acquired by the first photoelectric sensor and the second photoelectric sensor;
The external processor unit is used for analyzing the demodulation signal obtained by the phase-locked amplifying module and inverting the concentration of the gas to be detected.
In the technical scheme, the external processor unit comprises a processor and a storage medium, wherein the processor is electrically connected with the storage medium, and a computer program is stored in the storage medium;
the processor is used for executing a computer program stored in the storage medium to realize the processing of the demodulation signals transmitted by the laser ranging unit and the phase-locked amplifying module.
The invention has the following beneficial effects:
the frequency division multiplexing type multi-component compact laser gas detection module effectively realizes optical path multiplication through the refraction of laser signals in the closed air cavity, realizes the frequency division multiplexing detection of various gases with different concentrations through simultaneously emitting laser signals with different frequencies, and is convenient for the connection of the laser signals with an external system and easy to process and calibrate because the emitting end and the receiving end of the laser signals are positioned on the same side.
The frequency division multiplexing type multi-component compact laser gas detection system can realize simultaneous detection of the concentration of various gases to be detected in the same scanning period, and has the characteristics of high timeliness and high reliability.
Drawings
The invention is described in further detail below with reference to the drawings and the detailed description.
FIG. 1 is a schematic diagram of a frequency division multiplexed multi-component compact laser gas detection module of the present invention;
Fig. 2 is a schematic diagram of the working principle of the frequency division multiplexing type multi-component compact laser gas detection module of the invention.
Reference numerals in the drawings denote:
1-a housing, 2-a gas diffusion membrane, 3-a second total reflection mirror;
20-a first optical module, 30-a second optical module;
4-third total reflection mirror, 5-fourth total reflection mirror, 6-first total reflection mirror, 7-first focusing lens;
8-fifth total reflection mirror, 9-first photoelectric sensor, 10-laser unit, 11-sixth total reflection mirror, 12-second photoelectric sensor, 13-semi-transparent semi-reflection mirror, 14-gas baffle, 15-collimating lens, 16-second converging lens and 17-reference gas chamber.
Detailed Description
The present invention will be described in detail with reference to the accompanying drawings.
As shown in fig. 1 and 2, the frequency division multiplexing type multi-component compact laser gas detection module of the invention comprises a shell 1, a first optical module 20, a gas baffle 14, a laser group 10 and a first photoelectric sensor 9;
the shell 1 is provided with a gas diffusion film 2, and the shell 1 can adopt a structure with anti-vibration and airtight functions and can be used for fixing devices such as a reflector, a lens, a photoelectric sensor, a laser set 10 and the like which are arranged in the inner cavity of the shell 1.
The first optical module 20 comprises a composite mirror, a second total reflection mirror 3, a third total reflection mirror 4 and a fourth total reflection mirror 5, wherein the composite mirror and the second total reflection mirror 3 are mutually perpendicular and arranged on the inner wall of one side of the shell 1, the third total reflection mirror 4 and the fourth total reflection mirror 5 are mutually perpendicular and arranged on the inner wall of the other side of the shell 1, the composite mirror is parallel to the third total reflection mirror 4, and the second total reflection mirror 3 is parallel to the fourth total reflection mirror 5. The compound mirror comprises a first total reflecting mirror 6 and a half-transmitting half-reflecting mirror 13, wherein the first total reflecting mirror 6 and the half-transmitting half-reflecting mirror 13 are integrally arranged. The composite mirror can realize different reflectivities and transmittances at different positions by changing the surface coating, so that the composite mirror is divided into a half mirror 13 and a first total reflection mirror 6.
The gas baffle 14 is arranged in the shell 1, the gas baffle 14, the gas diffusion film 2 and the first optical module 20 form a closed air cavity, and the gas to be tested can enter the closed air cavity through the gas diffusion film 2. The gas barrier 14 may act to isolate the gas and prevent the gas to be measured from escaping from the closed air cavity.
The laser set 10 is used for emitting laser signals into the closed air cavity, and in this embodiment, the laser set 10 is a near infrared laser. The near infrared laser can effectively widen the range of the detected gas. The laser set 10 is electrically connected to a laser driving unit, which sends a laser driving signal to the laser set 10, so that the laser set 10 sends a modulated laser signal according to the corresponding driving signal.
The first photoelectric sensor 9 and the laser set 10 are disposed on the same side, and are configured to receive a reflected signal of the laser signal after being folded by the first optical module 20, and convert the reflected signal into an electrical signal for output.
The frequency division multiplexing type multi-component compact laser gas detection module further comprises a reference light path, wherein the reference light path comprises a second optical module 30, a reference air chamber 17 and a second photoelectric sensor 12, laser signals sent out by the laser set 10 are divided into two paths after passing through the half mirror 13, one path of the laser signals continues to be folded in the closed air chamber, the other path of the laser signals enters the reference air chamber 17 after being folded by the second optical module 30, and the second photoelectric sensor 12 is used for converting the laser signals absorbed by the mixed reference gas in the reference air chamber 17 into electric signals and outputting the electric signals so as to realize frequency division multiplexing type detection of the gas. The mixed reference gas is introduced into the reference gas chamber 17, the laser signal is fully absorbed by the mixed reference gas inside after being injected into the reference gas chamber 17, and the output laser signal is converted into an electric signal by the second photoelectric sensor 12 and can be used for gas peak searching and concentration inversion reference signals.
The second optical module 30 includes a fifth total reflection mirror 8 and a sixth total reflection mirror 11, the fifth total reflection mirror 8 is used for turning over the laser signal transmitted through the half mirror 13, and the sixth total reflection mirror 11 is arranged perpendicular to the fifth total reflection mirror 8 and is used for receiving the laser signal turned over by the fifth total reflection mirror 8 and turning over the received laser signal to the reference air chamber 17. The fifth total reflection mirror 8 and the sixth total reflection mirror 11 are used for turning the laser signals entering the reference light path, so that one of the transmitting end and the receiving end (the position of the second photoelectric sensor 12) of the laser set 10 can be arranged on the same side in the shell 1, and the laser set is more convenient to be connected with an external processing system during use.
In this embodiment, the casing 1 is in a cuboid shape, three interfaces are arranged at the lower side of the short side of the bottom of the casing 1 and are used for connecting the laser set 10, the first photoelectric detector 9 and the second photoelectric detector 12, the long side and the side face of the upper side of the casing 1 can be provided with the gas diffusion film 2, the second total reflecting mirror 3 is positioned at the upper left part inside the casing 1, the third total reflecting mirror 4 is positioned at the upper right part inside the casing 1, the fourth total reflecting mirror 5 is positioned at the middle upper right part inside the casing 1, the composite mirror formed by the first total reflecting mirror 6 and the semi-transparent half reflecting mirror 13 is positioned at the lower left part inside the casing 1, the fifth total reflecting mirror 8 and the sixth total reflecting mirror 11 are positioned at the lower left part inside the casing 1, the gas baffle 14 is positioned at the lower part inside the casing 1, the first converging lens 7, the collimating lens 15 and the second converging lens 16 are positioned at the lower right part inside the casing 1 and are sequentially arranged from top to bottom, the first photoelectric detector 9, the laser set 10 and the second photoelectric detector 12 are positioned at the right part inside the casing 1 and are sequentially arranged from top to bottom right part inside the casing 17.
The casing 1 is further provided with a first interface and a second interface at the side where the first photoelectric sensor 9 is located, the first interface is electrically connected with the first photoelectric sensor 9, and the second interface is electrically connected with the laser set 10. In other embodiments, a third interface may be further disposed on the side where the first interface and the second interface are located, where the third interface is electrically connected to the second photosensor 12. Because the first interface, the second interface and the third interface are all positioned on the same side of the shell, the structure of the detection module is more compact, and the detection module is convenient to connect with an external processing system.
In this embodiment, the laser driving unit electrically connected to the laser group 10 includes a low-frequency scanning signal generating unit for generating a low-frequency scanning signal, a high-frequency modulating signal generating unit for generating a high-frequency modulating signal, a signal superimposing unit for superimposing the low-frequency scanning signal and the high-frequency modulating signal as a modulated laser signal, and a temperature control unit for adjusting the temperature of the modulated laser signal and making it at an operating temperature. In other embodiments, the laser driving unit further comprises a voltage controlled constant current source.
The low-frequency scanning signals and the high-frequency modulating signals are overlapped to different degrees through the signal overlapping unit, so that modulating laser signals with different frequencies can be obtained, and the laser is driven to generate laser signals with different frequencies.
The working process of the frequency division multiplexing type multi-component compact laser gas detection module system of the invention is as shown in fig. 2:
The laser signal emitted by the laser group 10 is divided into two paths after passing through the semi-transparent and semi-reflective mirror 13 in the composite mirror, one path of reflection continues to be folded in the closed air cavity, and the other path of reflection enters the reference light path. The laser signal entering the closed air cavity is reflected by the second total reflecting mirror 3, the third total reflecting mirror 4, the fourth total reflecting mirror 5, the first total reflecting mirror 6, the second total reflecting mirror 3, the fourth total reflecting mirror 5, the third total reflecting mirror 4, the second total reflecting mirror 3 and the first total reflecting mirror 6 in sequence and then is received by the first photoelectric sensor 9. The first photoelectric sensor 9 can convert the received laser reflected signal into an electric signal and output the electric signal to the external processing system as a detection signal, and the external processing system analyzes according to the electric signal so as to realize detection of the concentration of the gas to be detected in the closed air cavity, thereby judging whether the gas leakage phenomenon occurs.
In some embodiments, the frequency division multiplexing multi-component compact laser gas detection module further comprises a collimating lens 15, wherein the collimating lens 15 is arranged on an optical path before the laser signal enters the closed air cavity and is used for collimating the laser signal emitted by the laser set 10, and the laser set 10 is arranged at a focal point of the collimating lens 15. By providing the collimator lens 15, it is possible to perform convergent collimation on the signal emitted from the laser group 10.
In some embodiments, the frequency division multiplexing multi-component compact laser gas detection module further comprises a second converging lens 16, wherein the second converging lens 16 is arranged between the second optical module 30 and the reference air chamber 17 on the reference optical path and is used for focusing the laser signal folded by the second optical module 30 to the second photoelectric sensor 12, and the second photoelectric sensor 12 is arranged at the focal position of the second converging lens 16. By providing the second converging lens 16, the laser reflected signal after being folded by the second optical module 30 can be converged into the second photoelectric sensor 12, so that the second photoelectric sensor 12 can convert and output the laser reflected signal conveniently.
In some embodiments, the frequency division multiplexing multi-component compact laser gas detection module further includes a first focusing lens 7, where the first focusing lens 7 is disposed at the outlet of the closed air cavity, and is configured to focus the reflected signal after being folded by the first optical module 20 to the first photoelectric sensor 9, and the first photoelectric sensor 9 is disposed at the focal position of the first focusing lens 7. By arranging the first focusing lens 7, the laser reflected signals after being folded by the first optical module 20 can be focused into the first photoelectric sensor 9, so that the first photoelectric sensor 9 can convert and output the signals conveniently.
The frequency division multiplexing type multi-component compact laser gas detection module effectively realizes optical path multiplication through the refraction of laser signals in the closed air cavity, realizes the frequency division multiplexing detection of various gases with different concentrations through simultaneously emitting laser signals with different frequencies, and is convenient for the connection of the laser signals with an external system and easy to process and calibrate because the emitting end and the receiving end of the laser signals are positioned on the same side.
In a second aspect, the invention also provides a frequency division multiplexing type multi-component compact laser gas detection system, which comprises a laser gas detection module, a phase-locked amplifying module and an external processor unit, wherein the laser gas detection module is the frequency division multiplexing type multi-component compact laser gas detection module according to the first aspect of the invention, the phase-locked amplifying module is respectively and electrically connected with the first photoelectric sensor 9 and the second photoelectric sensor 12 and is used for processing electric signals acquired by the first photoelectric sensor 9 and the second photoelectric sensor 12, and the external processor unit is used for analyzing demodulation signals acquired by the phase-locked amplifying module and inverting the concentrations of various gases to be detected.
In the invention, the phase-locked amplifying module obtains an absorption signal containing a high-frequency sine wave modulation component and a low-frequency sawtooth wave scanning frequency component from the output electric signal of the second photoelectric sensor 12 through the first harmonic amplitude at the high-frequency modulation frequency of the corresponding laser, and uses the absorption signal as a reference signal to detect the output electric signal of the first photoelectric sensor 9, demodulate the second harmonic spectrum component representing the corresponding gas concentration at the high-frequency modulation frequency of the corresponding laser, and obtain the concentration of the mixed gas to be detected through inversion of an external processing unit, thereby realizing the frequency division multiplexing type gas detection.
In the invention, the external processor unit comprises a processor and a storage medium, wherein the processor is electrically connected with the storage medium, a computer program is stored in the storage medium, and the processor is used for executing the computer program stored in the storage medium so as to realize the processing of the demodulation signals transmitted by the laser ranging unit and the phase-locked amplifying module.
The external processor unit may be a computer device including, but not limited to, a personal computer, a server, a general purpose computer, a special purpose computer, a network device, an embedded device, a programmable device, an intelligent mobile terminal, an intelligent home device, a wearable intelligent device, a vehicle-mounted intelligent device, etc. Storage media include, but are not limited to, RAM, ROM, magnetic disk, magnetic tape, optical disk, flash memory, U disk, removable hard disk, memory card, memory stick, network server storage, network cloud storage, and the like. Processors include, but are not limited to, CPUs (central processing units), GPUs (image processors), MCUs (microprocessors), and the like.
The frequency division multiplexing type multi-component compact laser gas detection system can realize simultaneous detection of the concentration of various gases to be detected in the same scanning period, and has the characteristics of high timeliness and high reliability.
It is apparent that the above examples are given by way of illustration only and are not limiting of the embodiments. Other variations or modifications of the above teachings will be apparent to those of ordinary skill in the art. It is not necessary here nor is it exhaustive of all embodiments. While still being apparent from variations or modifications that may be made by those skilled in the art are within the scope of the invention.
Claims (10)
1. The frequency division multiplexing type multi-component compact laser gas detection module is characterized by comprising a shell (1), a first optical module (20), a gas baffle (14), a laser group (10) and a first photoelectric sensor (9);
the shell (1) is provided with a gas diffusion film (2);
The first optical module (20) comprises a compound mirror and a plurality of total reflectors, wherein the compound mirror comprises a first total reflector (6) and a semi-transparent semi-reflective mirror (13), and different reflectivities and transmittances of the compound mirror are realized at different positions by changing surface coatings;
the gas baffle (14) is arranged in the shell (1), and the gas baffle (14), the gas diffusion membrane (2) and the first optical module (20) form a closed air cavity;
The laser device group (10) is used for sending out laser signals into the closed air cavity;
The first photoelectric sensor (9) is used for receiving a reflected signal of a laser signal sent by the laser group (10) after being folded by the first optical module (20), converting the reflected signal into an electric signal and then outputting the electric signal;
The laser gas detection module further comprises a reference light path, wherein the reference light path comprises a second optical module (30), a reference air chamber (17) and a second photoelectric sensor (12), laser signals emitted by the laser group (10) are divided into two paths after passing through the semi-transparent semi-reflective mirror (13), one path of the laser signals is continuously folded in the closed air chamber, and the other path of the laser signals enters the reference air chamber (17) after being folded by the second optical module (30);
The mixed reference gas is introduced into the reference gas chamber (17), the laser signal is fully absorbed by the mixed reference gas after being injected into the reference gas chamber (17), and the output laser signal is converted into an electric signal by the second photoelectric sensor (12) and then is used for the reference signal of gas peak searching and concentration inversion, so that the frequency division multiplexing detection of the gas is realized.
2. The frequency division multiplexing type multi-component compact laser gas detection module of claim 1, wherein the plurality of total reflectors comprise a second total reflector (3), a third total reflector (4) and a fourth total reflector (5), wherein the second total reflector (3) and the compound reflector are mutually perpendicular to be arranged on the inner wall of one side of the shell (1), the third total reflector (4) and the fourth total reflector (5) are mutually perpendicular to be arranged on the inner wall of the other side of the shell (1), the third total reflector (4) and the compound reflector are arranged in parallel, and the second total reflector (3) and the fourth total reflector (5) are arranged in parallel.
3. The frequency division multiplexing multi-component compact laser gas detection module according to claim 1, wherein the second optical module (30) comprises a fifth total reflection mirror (8) and a sixth total reflection mirror (11), the fifth total reflection mirror (8) is used for turning over the laser signal transmitted through the half-transmission mirror (13), and the sixth total reflection mirror (11) is arranged perpendicular to the fifth total reflection mirror (8) and is used for receiving the laser signal after turning over through the fifth total reflection mirror (8) and turning over the received laser signal to the reference air chamber (17).
4. The frequency division multiplexing multi-component compact laser gas detection module according to claim 1, wherein the laser group (10) is a near infrared laser and is electrically connected to a laser driving unit, and the laser driving unit sends a laser driving signal to the laser group (10) so that the laser group (10) sends a modulated laser signal according to the corresponding driving signal.
5. The frequency division multiplexing type multi-component compact laser gas detection module according to claim 4, wherein the laser driving unit comprises a low-frequency scanning signal generating unit, a high-frequency modulation signal generating unit, a signal superposition unit and a temperature control unit, wherein the low-frequency scanning signal generating unit is used for generating a low-frequency scanning signal, the high-frequency modulation signal generating unit is used for generating a high-frequency modulation signal, the signal superposition unit is used for superposing the low-frequency scanning signal and the high-frequency modulation signal into a modulated laser signal, and the temperature control unit is used for adjusting the temperature of the modulated laser signal and enabling the modulated laser signal to be at an operating temperature.
6. The frequency division multiplexing type multi-component compact laser gas detection module according to claim 1, further comprising a collimating lens (15), wherein the collimating lens (15) is arranged on an optical path before the laser signals enter the closed air cavity and is used for collimating the laser signals emitted by the laser group (10), and the laser group (10) is arranged at a focal point of the collimating lens (15).
7. The frequency division multiplexing type multi-component compact laser gas detection module according to claim 1, further comprising a second converging lens (16), wherein the second converging lens (16) is arranged between a second optical module (30) on the reference optical path and the reference air chamber (17) and is used for focusing the laser signal after being folded by the second optical module (30) to a second photoelectric sensor (12), and the second photoelectric sensor (12) is arranged at the focal position of the second converging lens (16).
8. The frequency division multiplexing type multi-component compact laser gas detection module according to claim 1, further comprising a first focusing lens (7), wherein the first focusing lens (7) is arranged at the outlet of the closed air cavity and is used for focusing the reflected signal after being folded by the first optical module (20) to the first photoelectric sensor (9), and the first photoelectric sensor (9) is arranged at the focal position of the first focusing lens (7).
9. The frequency division multiplexing type multi-component compact laser gas detection system is characterized by comprising a laser gas detection module, a lock-in amplifying module and an external processor unit;
the laser gas detection module is the laser gas detection module of any one of claims 1 to 8;
The phase-locked amplifying module is respectively and electrically connected with the first photoelectric sensor (9) and the second photoelectric sensor (12) and is used for processing electric signals acquired by the first photoelectric sensor (9) and the second photoelectric sensor (12);
The external processor unit is used for analyzing the demodulation signal obtained by the phase-locked amplifying module and inverting the concentration of the gas to be detected.
10. The frequency division multiplexed multiple component compact laser gas detection system of claim 9, wherein the external processor unit comprises a processor and a storage medium, the processor being electrically connected to the storage medium, the storage medium having a computer program stored therein;
the processor is used for executing a computer program stored in the storage medium to realize the processing of the demodulation signals transmitted by the laser ranging unit and the phase-locked amplifying module.
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| CN202411288257.1A CN119086492A (en) | 2024-09-14 | 2024-09-14 | Frequency division multiplexing multi-component compact laser gas detection module and detection system |
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| CN202411288257.1A CN119086492A (en) | 2024-09-14 | 2024-09-14 | Frequency division multiplexing multi-component compact laser gas detection module and detection system |
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