Device for detecting trace gas under strong spectrum background interference
By using a spectroscope in the trace gas detection device to divide the laser into two beams, detect trace gas and background gas respectively, and use the spectral model to process the signal, the problem of background interference affecting detection accuracy is solved, and more accurate trace gas detection is achieved.
Patent Information
- Application Number
- CN202411587127.8
- Authority / Receiving Office
- CN · China
- Patent Type
- Applications(China)
- Current Assignee / Owner
- Filing Date
- 2024-11-07
- Publication Date
- 2024-12-31
AI Technical Summary
In the laser absorption spectroscopy method, there is strong background absorption interference in the trace gas detection band, resulting in a lack of accuracy in the measurement results. Especially when the background gas concentration changes, it is difficult for the prior art to effectively avoid interference, affecting the detection accuracy.
Design a trace gas detection device under strong spectral background interference, divide the laser into two beams through a spectroscopic spectral, enter the long-path pool and the short-path pool respectively, detect the concentration of trace gas and background gas, and use the spectral model to invert the detection signal The background signal is deducted and the spectral curve of the gas to be measured is extracted to avoid the influence of changes in the background gas concentration.
It effectively solves the background interference problem, improves the accuracy of trace gas detection, and ensures that the accuracy of the detection results is not affected by changes in background gas concentration.
Smart Images
Figure CN119223921A_ABST
Abstract
Description
Technical Field
[0001] The invention relates to the technical field of gas detection, and in particular to a device for detecting trace gases under strong spectral background interference. Background Art
[0002] In the laser absorption spectroscopy method, the detection band of trace gases is mainly 1um-2um, and there is usually strong background absorption interference in this band, and the background interference intensity is usually more than two orders of magnitude higher than the object to be detected, such as hydrogen sulfide measurement under methane background. The existing technology uses calibration and fitting methods to avoid background interference, but when the background gas concentration changes, the measurement results usually change, resulting in a lack of accuracy in the gas detection results. Therefore, a device for trace gas detection under strong spectral background interference is proposed. Summary of the invention
[0003] The purpose of the present invention is to provide a device for detecting trace gases under strong spectral background interference to solve the problems raised in the above background technology.
[0004] In order to solve the above technical problems, the present invention provides the following technical solutions: A device for detecting trace gases under strong spectral background interference, comprising a shell, a cavity is arranged in the shell, one end of the cavity is fixedly connected to a first plano-concave mirror, the first plano-concave mirror is fixedly connected to a plane mirror, the other end of the cavity is fixedly connected to a second plano-concave mirror, a window mirror is arranged on one side of the second plano-concave mirror, a third photosensitive detector is arranged on one side of the window mirror, a reflector is arranged on one side of the third photosensitive detector, a spectrometer is arranged on the top of the reflector, a second photosensitive detector is arranged on the top of the spectrometer, a reference gas chamber is arranged on one side of the spectrometer, a first photosensitive detector is arranged on one side of the reference gas chamber, a collimating lens is arranged on the bottom of the reference gas chamber, the collimating lens is arranged on one side of the spectrometer, and a light-emitting diode is arranged on one side of the collimating lens.
[0005] Preferably, one side of the cavity is conductively connected to a first accommodating groove, and the first plano-concave mirror is fixedly connected in the first accommodating groove.
[0006] Preferably, a first end cover is provided on one side of the first plano-concave mirror, and the first end cover is fixedly connected in the housing.
[0007] Preferably, the other side of the cavity is conductively connected to a second accommodating groove, and the second plano-concave mirror is fixedly connected to the second accommodating groove, a second end cover is provided on one side of the second plano-concave mirror, and the second end cover is fixedly connected to the shell, a first mounting seat is fixedly connected to the second end cover, a first mounting hole is provided on the first mounting seat, and the light-emitting diode is fixedly connected to one end of the first mounting hole, a collimating lens is fixedly connected to the other end of the first mounting hole, a second mounting hole is provided at the top of the first mounting hole, and the first photosensitive detector is fixedly connected to one end of the second mounting hole, a reference air chamber is fixedly connected to the other end of the second mounting hole, a second mounting seat is fixedly connected to the first mounting seat, and the spectrometer, the second photosensitive detector, the reflector and the third photosensitive detector are all fixedly connected to the second mounting seat, a third mounting seat is fixedly connected to the second mounting seat, and the window mirror is fixedly connected to the third mounting seat.
[0008] Preferably, a first bracket is fixedly connected in the first mounting seat, and the spectrometer and the third photosensitive detector are both fixedly connected to the first bracket, a second bracket is fixedly connected in the first mounting seat, and the reflector is fixedly connected to the second bracket, a third bracket is fixedly connected in the third mounting seat, and the window mirror is fixedly connected to the third bracket.
[0009] Preferably, a first exit hole is provided on the second plano-concave mirror, a first entrance hole is provided at the bottom of the first exit hole, a second exit hole is provided at the bottom of the first entrance hole, and a second entrance hole is provided at the bottom of the second exit hole.
[0010] Preferably, two threaded holes are provided in the cavity, and air pipe joints are threadedly connected in the threaded holes.
[0011] Preferably, the first mounting seat is provided with a first positioning hole, a first positioning block is sleeved in the first positioning hole, and the first positioning block is fixedly connected to the second mounting seat, the second mounting seat is provided with a second positioning hole, a second positioning block is sleeved in the second positioning hole, and the second positioning block is fixedly connected to the third mounting seat.
[0012] The present invention provides a device for detecting trace gases under strong spectral background interference, which has the advantages that: the present invention constructs a background gas detection optical path and a trace gas detection optical path, divides the laser into two beams through a spectroscope, and makes them enter a long optical path cell and a short optical path cell respectively, thereby detecting the trace gas concentration and the background gas concentration, and after the background gas concentration is measured, it can be brought into the spectral model to infer the detection signal, and then the real-time detection signal is used to deduct the inverted background signal to extract the spectral curve of the gas to be measured, so that it is not affected by the change of background gas concentration, thereby effectively solving the background interference problem and improving the trace gas detection accuracy. BRIEF DESCRIPTION OF THE DRAWINGS
[0013] In order to more clearly illustrate the embodiments of the present invention or the technical solutions in the prior art, the drawings required for use in the embodiments or the description of the prior art will be briefly introduced below. Obviously, the drawings described below are some embodiments of the present invention. For ordinary technicians in this field, other drawings can be obtained based on these drawings without paying creative work.
[0014] Figure 1 It is a schematic diagram of the overall front view cutaway structure of the present invention;
[0015] Figure 2 It is a schematic diagram of the overall three-dimensional structure of the present invention;
[0016] Figure 3 It is a schematic diagram of the three-dimensional cutaway structure of the housing of the present invention;
[0017] Figure 4 It is a schematic diagram of the main view cutaway structure of the second plano-concave mirror of the present invention;
[0018] Figure 5 It is a schematic diagram of the three-dimensional structure of the first mounting base of the present invention;
[0019] Figure 6 It is a schematic diagram of the three-dimensional structure of the second mounting base of the present invention.
[0020] In the figure: 1, shell; 11, cavity; 12, threaded hole; 13, trachea joint; 14, first receiving groove; 15, first plano-concave mirror; 16, plane mirror; 17, first end cover; 18, second receiving groove; 19, second plano-concave mirror; 110, first exit hole; 111, first entrance hole; 112, second exit hole; 113, second entrance hole; 114, second end cover; 2, first mounting seat; 21, first mounting hole; 22, light emitting diode; 23, collimating lens Mirror; 24, second mounting hole; 25, first photosensitive detector; 26, reference gas chamber; 27, second mounting seat; 28, spectroscope; 29, second photosensitive detector; 210, reflector; 211, third photosensitive detector; 212, third mounting seat; 213, window mirror; 214, first positioning hole; 215, first positioning block; 216, second positioning hole; 217, second positioning block; 218, first bracket; 219, second bracket; 220, third bracket. DETAILED DESCRIPTION
[0021] In order to make the purpose, technical solution and advantages of the embodiments of the present invention clearer, the technical solution in the embodiments of the present invention will be clearly and completely described below in conjunction with the drawings in the embodiments of the present invention. Obviously, the described embodiments are part of the embodiments of the present invention, not all of the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by ordinary technicians in this field without creative work are within the scope of protection of the present invention.
[0022] Please refer to the attached Figure 1 -Attached Figure 6 An embodiment of the present invention is as follows: a device for detecting trace gases under strong spectral background interference, comprising a housing 1, a cavity 11 is arranged in the housing 1, a first plano-concave mirror 15 is fixedly connected to one end of the cavity 11, a plane mirror 16 is fixedly connected to the first plano-concave mirror 15, a second plano-concave mirror 19 is fixedly connected to the other end of the cavity 11, a window mirror 213 is arranged on one side of the second plano-concave mirror 19, a third photosensitive detector 211 is arranged on one side of the window mirror 213, and a third photosensitive detector 211 is arranged on one side of the third photosensitive detector 211 A reflector 210 is provided with a beam splitter 28 at the top of the reflector 210, a second photosensitive detector 29 is provided at the top of the beam splitter 28, a reference gas chamber 26 is provided on one side of the beam splitter 28, a first photosensitive detector 25 is provided on one side of the reference gas chamber 26, a collimating lens 23 is provided at the bottom of the reference gas chamber 26, and the collimating lens 23 is provided on one side of the beam splitter 28, and a light emitting diode 22 is provided on one side of the collimating lens 23. The optical path for detecting trace gas is as follows: the laser is split by the beam splitter 28, and is reflected by the reflector 210. The light path of background gas detection is as follows: the laser is split by the beam splitter 28, enters the first incident hole 111 through the window mirror 213, enters the short optical path pool, is reflected by the plane mirror 16, and is emitted from the first exit hole 110, and then is split into two by the beam splitter 28, one of which is directly The second photosensitive detector 29 collects and obtains the background gas concentration, and the other beam of light passes through the reference gas chamber 26 and is received by the first photosensitive detector 25, which is the reference light path; one side of the cavity 11 is connected to the first accommodating groove 14, and the first plano-concave mirror 15 is fixedly connected in the first accommodating groove 14, and the first accommodating groove 14 is used to accommodate the first plano-concave mirror 15; a first end cover 17 is provided on one side of the first plano-concave mirror 15, and the first end cover 17 is fixedly connected in the shell 1, and the first end cover 17 is used to support and fix the first plano-concave mirror 15.
[0023] The other side of the cavity 11 is connected to the second receiving groove 18, and the second plano-concave mirror 19 is fixedly connected to the second receiving groove 18, a second end cover 114 is provided on one side of the second plano-concave mirror 19, and the second end cover 114 is fixedly connected to the shell 1, and the first mounting seat 2 is fixedly connected in the second end cover 114, the first mounting seat 2 is provided with a first mounting hole 21, and the light-emitting diode 22 is fixedly connected to one end of the first mounting hole 21, the collimating lens 23 is fixedly connected to the other end of the first mounting hole 21, the top of the first mounting hole 21 is provided with a second mounting hole 24, and the first photosensitive detector The device 25 is fixedly connected to one end of the second mounting hole 24, the reference air chamber 26 is fixedly connected to the other end of the second mounting hole 24, the second mounting seat 2 is fixedly connected to the first mounting seat 2, and the spectrometer 28, the second photosensitive detector 29, the reflector 210 and the third photosensitive detector 211 are all fixedly connected in the second mounting seat 27, the second mounting seat 27 is fixedly connected to the third mounting seat 212, and the window mirror 213 is fixedly connected in the third mounting seat 212, the second accommodating groove 18 is used to accommodate the second plano-concave mirror 19, and the second end cover 114 is used to support and fix the second plano-concave mirror 19.
[0024] The first mounting hole 21 on the first mounting seat 2 is used to mount the light emitting diode 22 and the collimating lens 23, and the second mounting hole 24 is used to mount the first photosensitive detector 25 and the reference gas chamber 26; the second mounting seat 27 is used to mount the spectroscope 28, the second photosensitive detector 29, the reflector 210 and the third photosensitive detector 211, and the third mounting seat 212 is used to mount the window mirror 213; the first mounting seat 2 is fixedly connected with the first bracket 218, and the spectroscope 28 and the third photosensitive detector 211 are fixedly connected to the first bracket 218, and the first mounting seat 2 is fixedly connected with the first bracket 218. The first mounting base 212 is fixedly connected with a second bracket 219, and the reflector 210 is fixedly connected to the second bracket 219, the third mounting base 212 is fixedly connected with a third bracket 220, and the window mirror 213 is fixedly connected to the third bracket 220, the first bracket 218 is used to install the spectroscope 28 and the third photosensitive detector 211, the second bracket 219 is used to install the reflector 210, and the third bracket 220 is used to install the window mirror 213; the second plano-concave mirror 19 is provided with a first exit hole 110, and the bottom end of the first exit hole 110 is provided with a first incident hole 111, and the first incident hole 112 is provided with a first incident hole 111. The bottom of the hole 111 is provided with a second exit hole 112, and the bottom of the second exit hole 112 is provided with a second entrance hole 113. The first exit hole 110 and the first entrance hole 111 are through holes for the laser to enter and exit the short optical path pool, and the second exit hole 112 and the second entrance hole 113 are through holes for the laser to enter and exit the long optical path pool; two threaded holes 12 are provided in the cavity 11, and the threaded holes 12 are connected with a trachea joint 13, and the threaded holes 12 are used to install the trachea joint 13, and the trachea joint 13 is used to connect the trachea; the first mounting seat 2 is provided with a first positioning hole 214, and the first positioning hole 214 is provided on the first mounting seat 2. A first positioning block 215 is sleeved in the hole 214, and the first positioning block 215 is fixedly connected to the second mounting seat 27. A second positioning hole 216 is opened on the second mounting seat 27. A second positioning block 217 is sleeved in the second positioning hole 216, and the second positioning block 217 is fixedly connected to the third mounting seat 212. The first positioning hole 214 cooperates with the first positioning block 215 to achieve positioning between the first mounting seat 2 and the second mounting seat 27. The second positioning hole 216 cooperates with the second positioning block 217 to achieve positioning between the third mounting seat 212 and the second mounting seat 27.
[0025] Working principle: When the present invention is used, the light emitting diode 22 emits a laser, which is irradiated onto the beam splitter 28 through the collimating lens 23. The beam splitter 28 divides the laser into two beams. One beam is reflected by the reflector 210 to the window mirror 213, enters the second incident hole 113 through the window mirror 213, enters the long optical path pool, is reflected multiple times between the first plano-concave mirror 15 and the second plano-concave mirror 19, and finally is emitted from the second exit hole 112, irradiated onto the third photosensitive detector 211, and is used to detect the concentration of trace gases; the other beam enters the first incident hole 111 through the window mirror 213, enters the short optical path pool, is reflected by the plane mirror 16, and exits from the first exit hole 112. The laser beam is emitted from the hole 110 and then split into two by the spectroscope 28. One of the beams is directly collected by the second photosensitive detector 29 to obtain the background gas concentration. The other beam is received by the first photosensitive detector 25 after passing through the reference gas chamber 26. This branch is used to monitor the light intensity and wavelength self-stabilization of the laser. When the background gas concentration is measured, it can be brought into the spectrum model to infer the detection signal. The spectrum curve of the gas to be detected can be extracted by deducting the inverted background signal from the real-time detection signal, so that it is not affected by the change of the background gas concentration. Among them, the cavity 11 in the shell 1 is used to accommodate the gas to be detected, and the threaded hole 12 is used to install the gas pipe joint 13. The gas pipe joint 13 For access to the trachea, the first accommodating groove 14 is used to accommodate the first plano-concave mirror 15, the first end cover 17 is used to abut and fix the first plano-concave mirror 15, the second accommodating groove 18 is used to accommodate the second plano-concave mirror 19, the second end cover 114 is used to abut and fix the second plano-concave mirror 19, the first mounting hole 21 on the first mounting seat 2 is used to install the light-emitting diode 22 and the collimating lens 23, the second mounting hole 24 is used to install the first photosensitive detector 25 and the reference gas chamber 26; the second mounting seat 27 is used to install the spectroscope 28, the second photosensitive detector 29, the reflector 210 and the third photosensitive detector 211, and the second mounting seat 27 is connected to the second mounting seat 27 through the first mounting hole 214. A bracket 218 is used to install the spectrometer 28 and the third photosensitive detector 211. The second mounting seat 27 is used to install the reflector 210 through the second bracket 219. The third mounting seat 212 is used to install the window mirror 213 through the third bracket 220. The first positioning hole 214 cooperates with the first positioning block 215 to achieve positioning between the first mounting seat 2 and the second mounting seat 27. The second positioning hole 216 cooperates with the second positioning block 217 to achieve positioning between the third mounting seat 212 and the second mounting seat 27. The first mounting seat 2, the second mounting seat 27 and the third mounting seat 212 are designed in series splicing, which makes the installation of the lens group more convenient.
[0026] In the description of the present invention, it should be noted that, unless otherwise clearly specified and limited, the terms "installed", "connected", and "connected" should be understood in a broad sense, for example, it can be a fixed connection, a detachable connection, or an integral connection; it can be a mechanical connection or an electrical connection; it can be a direct connection, or it can be indirectly connected through an intermediate medium, or it can be the internal communication of two components. For ordinary technicians in this field, the specific meanings of the above terms in the present invention can be understood according to specific circumstances.
[0027] The device embodiments described above are merely illustrative, wherein the units described as separate components may or may not be physically separated, and the components displayed as units may or may not be physical units, that is, they may be located in one place, or they may be distributed on multiple network units. Some or all of the modules may be selected according to actual needs to achieve the purpose of the scheme of this embodiment. Ordinary technicians in this field can understand and implement it without paying creative labor.
[0028] Finally, it should be noted that the above embodiments are only used to illustrate the technical solutions of the present invention, rather than to limit it. Although the present invention has been described in detail with reference to the aforementioned embodiments, those skilled in the art should understand that they can still modify the technical solutions described in the aforementioned embodiments, or make equivalent replacements for some of the technical features therein. However, these modifications or replacements do not deviate the essence of the corresponding technical solutions from the spirit and scope of the technical solutions of the embodiments of the present invention.
Claims
1. A device for detecting trace gases under strong spectral background interference, comprising a housing (1), characterized in that: A cavity (11) is provided in the housing (1), one end of the cavity (11) is fixedly connected to a first plano-concave mirror (15), the first plano-concave mirror (15) is fixedly connected to a plane mirror (16), the other end of the cavity (11) is fixedly connected to a second plano-concave mirror (19), a window mirror (213) is provided on one side of the second plano-concave mirror (19), a third photosensitive detector (211) is provided on one side of the window mirror (213), and a reflector (211) is provided on one side of the third photosensitive detector (211). 0), a spectroscope (28) is arranged at the top of the reflector (210), a second photosensitive detector (29) is arranged at the top of the spectroscope (28), a reference gas chamber (26) is arranged on one side of the spectroscope (28), a first photosensitive detector (25) is arranged on one side of the reference gas chamber (26), a collimating lens (23) is arranged at the bottom of the reference gas chamber (26), the collimating lens (23) is arranged on one side of the spectroscope (28), and a light-emitting diode (22) is arranged on one side of the collimating lens (23).
2. The device for detecting trace gases under strong spectral background interference according to claim 1, characterized in that: One side of the cavity (11) is conductively connected to a first accommodating groove (14), and a first plano-concave mirror (15) is fixedly connected in the first accommodating groove (14).
3. The device for detecting trace gases under strong spectral background interference according to claim 2, characterized in that: A first end cover (17) is provided on one side of the first plano-concave mirror (15), and the first end cover (17) is fixedly connected inside the housing (1).
4. The device for detecting trace gases under strong spectral background interference according to claim 1, characterized in that: The other side of the cavity (11) is conductively connected to a second accommodating groove (18), and a second plano-concave mirror (19) is fixedly connected to the second accommodating groove (18). A second end cover (114) is provided on one side of the second plano-concave mirror (19), and the second end cover (114) is fixedly connected to the housing (1). A first mounting seat (2) is fixedly connected to the second end cover (114), and a first mounting hole (21) is provided on the first mounting seat (2), and a light-emitting diode (22) is fixedly connected to one end of the first mounting hole (21), and a collimating lens (23) is fixedly connected to the other end of the first mounting hole (21). 1) A second mounting hole (24) is arranged at the top, and a first photosensitive detector (25) is fixedly connected to one end of the second mounting hole (24), a reference gas chamber (26) is fixedly connected to the other end of the second mounting hole (24), a second mounting seat (27) is fixedly connected to the first mounting seat (2), and a spectroscope (28), a second photosensitive detector (29), a reflector (210) and a third photosensitive detector (211) are all fixedly connected to the second mounting seat (27), a third mounting seat (212) is fixedly connected to the second mounting seat (27), and a window mirror (213) is fixedly connected to the third mounting seat (212).
5. The device for detecting trace gases under strong spectral background interference according to claim 4, characterized in that: A first bracket (218) is fixedly connected inside the first mounting seat (2), and the spectroscope (28) and the third photosensitive detector (211) are both fixedly connected to the first bracket (218); a second bracket (219) is fixedly connected inside the first mounting seat (2), and the reflector (210) is fixedly connected to the second bracket (219); a third bracket (220) is fixedly connected inside the third mounting seat (212), and the window mirror (213) is fixedly connected to the third bracket (220).
6. The device for detecting trace gases under strong spectral background interference according to claim 4, characterized in that: The second plano-concave mirror (19) is provided with a first emission hole (110), a first incidence hole (111) is arranged at the bottom of the first emission hole (110), a second emission hole (112) is arranged at the bottom of the first incidence hole (111), and a second incidence hole (113) is arranged at the bottom of the second emission hole (112).
7. The device for detecting trace gases under strong spectral background interference according to claim 4, characterized in that: Two threaded holes (12) are provided in the cavity (11), and an air pipe joint (13) is threadedly connected to the threaded holes (12).
8. The device for detecting trace gases under strong spectral background interference according to claim 4, characterized in that: The first mounting seat (2) is provided with a first positioning hole (214), a first positioning block (215) is sleeved in the first positioning hole (214), and the first positioning block (215) is fixedly connected to the second mounting seat (27); the second mounting seat (27) is provided with a second positioning hole (216), a second positioning block (217) is sleeved in the second positioning hole (216), and the second positioning block (217) is fixedly connected to the third mounting seat (212).