High-sensitivity substance concentration in-situ monitoring system suitable for deep space exploration task

Abstract

The invention discloses a high-sensitivity substance concentration in-situ monitoring system suitable for a deep space exploration task, and relates to the field of trace gas substance concentration monitoring in deep space exploration. Comprising a laser for exciting signal light, a drive of the laser, an adjusting frame for adjusting the incident position and angle of the signal light, a light spot matrix type optical multi-pass cell for reflecting the signal light for multiple times, and a signal processing module for detecting an output signal of the light spot matrix type optical multi-pass cell. According to the novel optical multi-pass cell provided by the invention, on the premise of ensuring uniform distribution of light spots, not only can high integration of a system be realized, but also the effective absorption optical path of gas can be improved to a great extent, and ultrahigh-sensitivity detection of trace gas of a deep space exploration task is realized.

Description

Technical Field

[0001] The present invention relates to the field of trace gas substance concentration monitoring in deep space exploration, and in particular to a high-sensitivity substance concentration in-situ monitoring system suitable for deep space exploration missions. Background Art

[0002] Deep space exploration is an inevitable way for mankind to explore the mysteries of the universe and seek sustainable development. It is also a major scientific and technological innovation field to enhance the country's basic innovation strength and security capabilities. Determining the material environment of celestial bodies is an extremely important point in deep space exploration, so the study of celestial material composition is the primary issue of deep space exploration. There is an interactive relationship between the atmosphere and the surface material on the celestial body, so only by combining the two can we truly analyze the material composition of the planetary surface. Monitoring the atmosphere on the planetary surface is an important goal of material composition research in planetary exploration. This is of great scientific significance for studying the formation process of planets, the long-term evolution of planetary geology, the long-term evolution of planetary surface composition, the interaction between rock and air, the interaction between rock and water, and the long-term changes in Martian landforms.

[0003] Among deep space exploration missions, Mars exploration is the planetary exploration project that humans are currently paying the most attention to. In the early days, Mars gas detection mainly used ground-based spectroscopy telemetry of the observatory, but due to the long detection distance, this detection method has low spatial resolution and is difficult to guarantee reliability. In order to solve this problem, a research team later carried out occultation remote sensing detection of the surface atmosphere on the Mars orbiter using planetary Fourier spectrometer technology, but the detection sensitivity of this technology is greatly affected by the visibility of the Mars surface (such as climate such as sandstorms), and it is difficult to perceive the changes in trace gas concentrations on the surface of Mars. Therefore, it is of great significance to achieve high-sensitivity and accurate detection of the gas material composition in the target area and ensure the integration and portability of the detection system for the detection of materials on the Mars surface and the planning and design of the Mars scientific research station and Mars green home. At present, only the United States' Curiosity has carried out in-situ gas material concentration detection on the Mars surface with a tunable absorption spectroscopy (TLS) detection system, but the detection sensitivity is still difficult to meet the demand. To improve the detection sensitivity of the tunable semiconductor laser absorption spectroscopy system, in addition to suppressing the noise in the signal, the length of the effective absorption optical path of the gas is also crucial. For the same concentration of the gas to be tested, the longer the absorption optical path, the greater the absorption signal and the higher the detection sensitivity of the system. At present, under the premise of ensuring the physical size of the optical cell, the design scheme of the optical cell that effectively improves the propagation optical path is still relatively lacking. Chinese patent application CN116380839A mentions a folded multi-incident optical path, which can improve the effective absorption optical path of the gas relative to the traditional Herriot cell while ensuring that the spatial length dimension remains unchanged. However, the multi-incident of CN116380839A needs to be based on the number of inner circle spot distributions, and the outer circle area of ​​the mirror is still not fully utilized. In the application of small diameter mirrors under small size restrictions, the multi-incident structure has almost no advantage. In planetary exploration missions such as the Mars Research Station, it is usually necessary to strictly limit the spatial size of the payload. Therefore, how to further improve the effective absorption optical path of the gas optical cell without increasing the system interference noise while ensuring the small size of the system structure has become a technical problem that needs to be solved urgently. Summary of the invention

[0004] In order to solve the technical problem of effectively improving the detection sensitivity of the system while ensuring the portability of the detection system, the present invention provides a miniaturized material concentration in-situ monitoring system suitable for deep space exploration missions. Through the proposed new optical multi-pass cell, while ensuring the uniform distribution of light spots, not only can the system be highly integrated, but also the effective absorption optical path of the gas can be greatly improved, thereby achieving ultra-high sensitivity detection of trace gases that meet deep space exploration missions.

[0005] In order to solve the above technical problems, the present invention provides the following technical solutions:

[0006] A high-sensitivity material concentration in-situ monitoring system suitable for deep space exploration missions, comprising a laser for exciting signal light and a driver thereof, an adjustment frame for adjusting the incident position and angle of the signal light, a novel light spot array optical multi-pass cell for multiple reflections of the signal light, and a signal processing module for detecting output signals of the novel light spot array optical multi-pass cell;

[0007] The novel light spot array optical multi-pass pool comprises a first high-reflection mirror and a second high-reflection mirror, wherein the reflection surfaces of the first high-reflection mirror and the second high-reflection mirror are both oriented toward the inside of the novel light spot array optical multi-pass pool, the first high-reflection mirror is provided with a small hole for the signal light to enter, and the second high-reflection mirror is provided with a small hole for the signal light to exit;

[0008] Furthermore, the output wavelength of the laser needs to be determined according to the absorption line positions of different types of gases to be measured;

[0009] Further, the first high-reflective mirror and the second high-reflective mirror are both cylindrical mirrors, the cylindrical surface is a reflective surface, and the first high-reflective mirror and the second high-reflective mirror are parallel to each other, the optical axes coincide, and the flat axis and the refractive power axis of the first high-reflective mirror and the second high-reflective mirror correspond to each other;

[0010] Furthermore, the first high-reflection mirror and the second high-reflection mirror are coated with a high-reflectivity film layer at the target absorption line of the gas to be measured. For the same high-reflection mirror, the incident coordinate x0 and the incident slope x0' of the refractive power axis and the single optical path length L are determined by a preset calculation formula;

[0011] The preset calculation formula is as follows:

[0012] (5)

[0013] (6)

[0014] (11)

[0015] Wherein, k is a constant, m is the number of single-period light spots formed on the surface of the first high-reflective mirror or the second high-reflective mirror, and the number of light spots formed on the surfaces of the first high-reflective mirror and the second high-reflective mirror is equal, θ is the angular frequency difference between adjacent light spots, r is the radius of curvature of the first high-reflective mirror or the second high-reflective mirror in the axial direction of the refractive power, x0 is the incident coordinate position of the signal light expressed with the cylindrical center of the first high-reflective mirror as the origin of the coordinates, x0' is the incident angle of the signal light, A is the maximum offset distance of the mirror light spot, the x-axis position of the incident pinhole of the reflective surface of the first high-reflective mirror and the second high-reflective mirror is consistent with the incident coordinate x0, and the single optical path length L needs to satisfy 0 <L<2r;

[0016] Furthermore, for the same high-reflection mirror, the incident coordinate y0 of the cylindrical mirror in the flat axis can be determined according to the range of the effective reflection surface of the cylindrical mirror in the flat axis, and the incident slope y0' of the cylindrical mirror in the flat axis is adjusted according to the longitudinal distance between the light spots in the same row of the mirror surface to ensure that there is no interference between the light spots;

[0017] Furthermore, the signal processing module includes a photoelectric detector, a signal acquisition unit and a processor corresponding to the outgoing signal light.

[0018] Beneficial effects:

[0019] (1) The present invention realizes a dot matrix multi-reflection light field distribution based on the proposed spot matrix optical multi-pass cell. While ensuring that the spatial length of the device remains unchanged and the interference noise between the spots is not increased, the effective absorption optical path of the system gas is increased by 4.2 times compared with the traditional Herriott multi-pass cell structure;

[0020] (2) The spot array optical multi-pass cell proposed in the present invention only requires two cylindrical mirrors to achieve an ultra-long effective absorption optical path, and has the advantages of simple structure, convenient adjustment, high stability, and low processing cost;

[0021] (3) The present invention provides a design method for a spot array optical multi-pass cell, which can adapt to the development requirements of loads with different spatial sizes and effective absorption optical paths.

[0022] In summary, the present invention proposes a new type of spot array optical multi-pass cell, which aims to effectively improve the utilization rate of the light spot of the mirror. Under the same spatial size, the long optical path new optical multi-pass cell proposed by the present invention can achieve an effective absorption optical path several times that of the traditional Herriott optical multi-pass cell while ensuring that the interference noise does not increase, thereby effectively ensuring high-sensitivity detection of atmospheric concentrations on planetary surfaces, and providing support and guarantee for the construction of Mars scientific research stations and Mars green homes. In addition, the present invention is also applicable to the monitoring of the earth's atmospheric environment, and has extremely important research value for promoting the industrialization of environmental atmospheric trace gas detection instruments and for evaluating the source and sink totals of greenhouse gases and emission reduction effects. BRIEF DESCRIPTION OF THE DRAWINGS

[0023] Figure 1 A schematic diagram of the principle of a miniaturized material concentration in-situ monitoring system suitable for deep space exploration missions provided by an embodiment of the present invention;

[0024] Figure 2 A schematic diagram of the optical structure of a spot array optical multi-pass cell provided in an embodiment of the present invention;

[0025] Figure 3 A schematic structural diagram of a spot array optical multi-pass cell provided in an embodiment of the present invention in an xz coordinate plane;

[0026] Figure 4 A schematic structural diagram of a spot array optical multi-pass cell provided in an embodiment of the present invention in the yz coordinate plane;

[0027] Figure 5 A schematic diagram of an optical equivalent analysis model of a spot array optical multi-pass cell provided in an embodiment of the present invention in an xz coordinate plane;

[0028] Figure 6 A schematic diagram of an optical equivalent analysis model of a spot array optical multi-pass cell provided in an embodiment of the present invention in the yz coordinate plane;

[0029] Figure 7 A schematic diagram of the geometric relationship analysis of the mirror light spot provided by an embodiment of the present invention;

[0030] Figure 8 A diagram showing the simulation results of the mirror spot distribution of a conventional Herriott optical multi-pass cell provided in an embodiment of the present invention;

[0031] Fig. 9 A diagram showing the simulation results of the mirror light spot distribution of the novel light spot array optical multi-pass cell provided in an embodiment of the present invention.

[0032] Among them, the figure markings are: laser driving module 1, quantum cascade laser 2, first plane reflector 3, second plane reflector 4, spot array optical multi-pass cell 5, first high reflector 51, second high reflector 52, photoelectric conversion unit 6, signal processing unit 7. DETAILED DESCRIPTION

[0033] In order to make the purpose, technical solutions and advantages of the present invention more clearly understood, the present invention is further described in detail below in conjunction with the accompanying drawings and embodiments. It should be understood that the specific embodiments described herein are only used to explain the present invention and are not intended to limit the present invention. In addition, the technical features involved in the various embodiments of the present invention described below can be combined with each other as long as they do not conflict with each other. The present invention is further described below in conjunction with the accompanying drawings and specific embodiments.

[0034] like Figure 1As shown, the miniaturized in-situ material concentration monitoring system suitable for deep space exploration missions according to the embodiment of the present invention comprises a laser driving module 1, a quantum cascade laser 2, a first plane reflector 3, a second plane reflector 4, a spot array optical multi-pass cell 5, a photoelectric conversion unit 6, and a signal processing unit 7. The laser driving module 1 realizes the current and temperature control of the quantum cascade laser 2. The laser emitted by the quantum cascade laser 2 is reflected by the first plane reflector 3 and the second plane reflector 4 in sequence and then enters the spot array optical multi-pass cell 5. The light beam is reflected multiple times in the spot array optical multi-pass cell 5 and then emitted into the photoelectric conversion unit 6. Finally, the photoelectric conversion unit 6 sends the electrical signal to the signal processing unit 7 to realize the calculation of the concentration of the gas to be measured.

[0035] The light spot array optical multi-pass cell 5 comprises a first high-reflection mirror 51 and a second high-reflection mirror 52 which are arranged opposite to each other. The first high-reflection mirror 51 and the second high-reflection mirror 52 are parallel to each other, and their optical axes coincide with each other. Figure 2 As shown; the laser beam passes through the small hole of the first high-reflection mirror 51 at a certain angle and enters the interior of the light spot array optical multi-pass pool 5, reaches the surface of the second high-reflection mirror 52, and then reaches the surface of the first high-reflection mirror 51 after being reflected by the surface of the second high-reflection mirror 52, and then reaches the surface of the second high-reflection mirror 52 after being reflected by the surface of the first high-reflection mirror 51, and then repeatedly forms multiple reflections and then emits from the small hole of the second high-reflection mirror 52. Fig. 9 As shown, the distance between the first high-reflection mirror 51 and the second high-reflection mirror 52 of the light spot array optical multi-pass cell 5 determines the distance of the light spots in the y-axis direction, thereby determining the certain angle.

[0036] One side of the first high-reflection mirror 51 and the second high-reflection mirror 52 is a cylindrical surface, and the other side is a plane. The cylindrical surface faces the inner side of the spot array optical multi-pass pool 5, and the other side is a plane. The cylindrical surface is a reflective surface, and the cylindrical surface is coated with a high reflectivity film layer of the absorption line band of the gas to be measured. The maximum offset distance of the side facing the inner side of the spot array optical multi-pass pool 5 can be determined according to the size of the mirror surface and the number of required spot distributions. Fig. 9 As shown in FIG. 1 , the maximum offset distance is the maximum spot distribution distance in the x-axis direction with the origin o as the reference. A Cartesian coordinate system is used, with the origin of the coordinates at the center of the reflection surface of the first high-reflection mirror 51, Z is the optical axis of the two reflectors, and the xy plane is parallel to the mirror surface. The light beam is incident at a certain slope ( , ) from position ( , ) is incident on a small hole at , and is reflected back and forth between the first high-reflection mirror 51 and the second high-reflection mirror 52. After n reflections, it is emitted from the small hole of the second high-reflection mirror 52. In space, the incident slope has two directions, one is the slope along the x-axis and the other is the slope along the y-axis. Therefore, the incident slope is expressed as ( , ).

[0037] Figure 2 In the embodiment, the focal lengths of the first high reflective mirror 51 and the second high reflective mirror 52 on the x-axis and y-axis are respectively equal. The focal lengths on the x-axis and y-axis are respectively f x and f y , on the xz plane, the first high-reflection mirror 51 and the second high-reflection mirror 52 can be regarded as concave mirrors, such as Figure 3 As shown, on the yz plane, the first high-reflection mirror 51 and the second high-reflection mirror 52 can be regarded as plane mirrors, as shown in FIG. Figure 4 shown.

[0038] For the convenience of analysis, equivalent models of the xz plane and the yz plane are established respectively. For the xz plane, after the laser beam is incident into the spot array optical multi-pass cell 5, each time it is reflected by the concave mirror surface of the first high-reflection mirror 51 and the second high-reflection mirror 52, it can be regarded as passing through the focal length f in the forward propagation process. x refracted after passing through a convex lens (an ideal lens with a thickness of 0), such as Figure 5 shown. Figure 5 In the figure, d is the distance between the two focusing lenses of the equivalent model, which is equal to the distance L between the first high-reflection mirror 51 and the second high-reflection mirror 52, and D is the thickness of the equivalent focusing lens. Ideally, D is 0 mm here.

[0039] For the yz plane, after the laser beam is incident into the spot array optical multi-pass cell 5, each time it is reflected by the flat mirror surface of the first high-reflection mirror 51 and the second high-reflection mirror 52, it can be regarded as refracted after passing through the flat lens (the ideal lens with a thickness of 0) during the forward propagation process, that is, it propagates forward in a straight line at the incident angle, such as Figure 6 shown.

[0040] In the xz plane, the beam moves from the coordinate At the incident slope The following formula can be obtained:

[0041] (1)

[0042] (2)

[0043] Where x' is the slope of the beam along the x-axis.

[0044] Depend on Figure 5The geometric relationship can be obtained:

[0045] (3)

[0046] The characteristic equation of formula (3) for:

[0047] ;

[0048] Where n is an integer (=0, 1…), x n is the x-axis coordinate of the light beam when it passes through the n+1th equivalent lens (i.e., the x-axis coordinate when the actual light spot array optical multi-pass cell reflects n+1 times), and r is the x-axis curvature radius of the first high-reflection mirror 51 and the second high-reflection mirror 52.

[0049] Therefore, formula (3) can be rewritten as:

[0050] (4)

[0051] Among them, A is the maximum offset distance of the light spot in the x direction, is the spatial phase difference between two adjacent light spots on the same reflector surface, is the initial phase. b1, b2 are constants, , and for The two roots.

[0052] Geometric analysis can also be performed in the polar coordinate system, such as Figure 7 To achieve re-incidence, it is necessary to ensure that:

[0053] (5)

[0054] ; (6)

[0055] Wherein, k and m are constants, L is the distance between the reflection surfaces of the first high-reflection mirror 51 and the second high-reflection mirror 52, which is equal to d in the equivalent model, and r is the curvature radius of the first high-reflection mirror 51 and the second high-reflection mirror 52 in the x-axis direction. Figure 7 You can get:

[0056] (7)

[0057] in, is the initial spatial phase angle of the first light spot, is the spatial phase angle between adjacent light spots, and A is the maximum offset.

[0058] According to formula (4) and formula (7), we can know that:

[0059] (8)

[0060] You can also get , when n = 0 and n = 1, according to formula (4), we can get:

[0061] (9)

[0062] (10)

[0063] Combining equations (3), (9) and (10), we can obtain:

[0064] (11)

[0065] First, determine the maximum offset distance A in the xz coordinate plane according to the preset spot distribution range, and then set the incident coordinates according to the required spot lateral distribution spacing requirements. The value of ), and finally calculate the incident slope according to formula (11): According to formula (4) or (7) and A, By setting the initial value of n, the coordinate point of each intersection of the reflected light beam and the mirror surface in the xz coordinate plane can be calculated.

[0066] Depend on Figure 6 It can be seen that the analysis for the yz coordinate plane is relatively simple. The plane lens of the equivalent optical model will not affect the beam propagation angle, so it can be obtained:

[0067] (12)

[0068] (13)

[0069] in, and respectively is the slope and coordinate of the y-axis when the light beam undergoes n+1 reflections.

[0070] The structural parameters of the proposed light spot array optical multi-pass cell 5 can be designed according to formula (1) to formula (13). At the same time, the point position of each reflected light spot can be obtained to further study and analyze the light spot array optical multi-pass cell 5 proposed by the present invention.

[0071] Under the assumption of application target requirements, the spot array optical multi-pass cell 5 proposed in the present invention is compared with the spot distribution of the traditional Herriott multi-pass cell. Assume that the length of the optical multi-pass cell is 18.8 cm, the effective reflection surface of the lens is a square area of ​​15×15 mm, and the spot diameter is 500 μm. For the traditional Herriott multi-pass cell, let its spot distribution radius be 7 mm, the incident point be (6.79 mm, 1.69 mm), and the incident slope be (-4.125, 0). The simulation results are as follows: Figure 8 As shown. Under the premise that the light spots do not overlap, the number of light spot distribution m can reach 71. For the light spot array optical multi-pass cell 5 proposed in the present invention, let its incident coordinates be (6 mm, 7.2 mm) and the incident slope be (-2.855, -0.007). The simulation results are shown as follows Fig. 9 Similarly, under the premise that no overlap occurs, it can be clearly observed that the light spot array optical multi-pass cell 5 of the present invention has a higher mirror utilization rate, and the number of light spot distribution is as high as 299.

[0072] Calculate the effective absorption path length of the multi-pass cell based on the number of light spot distributions , as shown in formula (14):

[0073] (14)

[0074] Wherein, m is the number of light spots distributed on the second high-reflection mirror 52 .

[0075] According to the above formula, the effective absorption path of the traditional Herriott multi-pass cell can reach 26.7m, and the RLV (ratio of the effective absorption path and volume of the optical multi-pass cell) is 6.3 cm -2 The effective absorption path of the spot array optical multi-pass cell 5 is 112.4m and the RLV value is 26.6 cm -2 According to the comparison results, under the premise of the same spatial size and non-overlapping of the light spots, the effective absorption optical path of the light spot array optical multi-pass cell 5 of the present invention is 4.2 times better than that of the traditional Herriott multi-pass cell, which can effectively improve the absorption optical path of the optical multi-pass cell under the condition of spatial size limitation.

[0076] In summary, under the same spatial dimensions, the spot array optical multi-pass cell proposed in the present invention not only has the advantages of the Herriott structure being simple and easy to adjust, but also under the premise of the same spatial dimensions and the spot not overlapping, its effective absorption optical path is 4.2 times better than that of the traditional Herriott multi-pass cell. The spot array optical multi-pass cell 5 of the present invention can effectively improve the absorption optical path of the gas to be measured under the condition of spatial dimension limitation, and is very suitable for application scenarios with strict spatial dimension limitation on the detection equipment and extremely high detection sensitivity detection requirements.

[0077] It is to be understood that the above embodiments are merely exemplary embodiments used to illustrate the principles of the present invention, but the present invention is not limited thereto. For those of ordinary skill in the art, various modifications and improvements can be made without departing from the spirit and essence of the present invention, and these modifications and improvements are also considered to be within the scope of protection of the present invention.

Claims

1. A highly sensitive in-situ material concentration monitoring system suitable for deep space exploration missions, characterized in that: It includes a laser driving module for exciting signal light, a first plane reflector and a second plane reflector for adjusting the incident position and angle of the signal light, a spot array optical multi-pass cell for multiple reflections of the signal light, and a signal processing unit for detecting output signals of the spot array optical multi-pass cell; The light spot array optical multi-pass pool includes a first high-reflection mirror and a second high-reflection mirror, the reflection surfaces of the first high-reflection mirror and the second high-reflection mirror are both facing the inner side of the light spot array optical multi-pass pool, the first high-reflection mirror is provided with an incident hole for the signal light to be injected, and the second high-reflection mirror is provided with an exit hole for the signal light to be emitted; the first high-reflection mirror and the second high-reflection mirror are both cylindrical mirrors, the cylinder is the reflection surface, and the first high-reflection mirror and the second high-reflection mirror are parallel to each other, and the optical axes coincide.

2. According to claim 1, a highly sensitive material concentration in-situ monitoring system suitable for deep space exploration missions is characterized in that: The wavelength of the laser output by the laser driving module is determined according to the absorption line positions of different types of gases to be measured.

3. The high-sensitivity material concentration in-situ monitoring system suitable for deep space exploration missions according to claim 1, characterized in that: The flat axis and the refractive power axis of the first high-reflection mirror and the second high-reflection mirror correspond to each other.

4. The high-sensitivity material concentration in-situ monitoring system suitable for deep space exploration missions according to claim 3, characterized in that: The first high-reflection mirror and the second high-reflection mirror are coated with a high-reflectivity film layer at the target absorption line of the gas to be measured. For the same high-reflection mirror, the incident coordinate x0 and incident slope x0' of the refractive power axis and the single optical path length L are determined by a preset calculation formula.

5. The high-sensitivity material concentration in-situ monitoring system suitable for deep space exploration missions according to claim 4, characterized in that: The preset calculation formula is as follows: （5） （6） （11） Wherein, k is a constant, m is the number of single-period light spots formed on the surface of the first high-reflection mirror or the second high-reflection mirror, and the number of light spots formed on the surface of the first high-reflection mirror and the second high-reflection mirror is equal. is the angular frequency difference between adjacent light spots, r is the radius of curvature of the first high-reflection mirror or the second high-reflection mirror in the axial direction of the refractive power, x0 is the incident coordinate of the signal light expressed with the center of the cylinder of the first high-reflection mirror as the origin of the coordinate, x0' is the incident slope of the signal light, A is the maximum offset distance of the mirror light spot, the x-axis position of the incident pinhole of the reflective surface of the first high-reflection mirror and the second high-reflection mirror is consistent with the incident coordinate x0, and the single optical path length L satisfies 0 <L<2r。 6. The high-sensitivity material concentration in-situ monitoring system suitable for deep space exploration missions according to claim 3, characterized in that: For the same high-reflection mirror, the incident coordinate y0 of the flat axis of the cylindrical mirror is determined according to the range of the effective reflection surface of the cylindrical mirror in the flat axis.

7. The high-sensitivity material concentration in-situ monitoring system suitable for deep space exploration missions according to claim 4, characterized in that: The incident slope y0' of the flat axis of the cylindrical mirror is adjusted according to the longitudinal distance between the light spots in the same row of the mirror surface to ensure that there is no interference between the light spots.

8. The high-sensitivity material concentration in-situ monitoring system suitable for deep space exploration missions according to claim 1, characterized in that: The signal processing unit includes a photoelectric detector corresponding to the outgoing signal light, a signal collection unit and a processor.

9. The high-sensitivity material concentration in-situ monitoring system suitable for deep space exploration missions according to claim 1, characterized in that: The laser driving module realizes the current and temperature control of the quantum cascade laser. The laser emitted by the quantum cascade laser is reflected by the first plane reflector and the second plane reflector in sequence and then enters the spot array optical multi-pass cell. The light beam is reflected multiple times in the spot array optical multi-pass cell and then emitted into the photoelectric conversion unit. Finally, the photoelectric conversion unit sends the electrical signal to the signal processing unit to realize the calculation of the concentration of the gas to be measured.

10. The high-sensitivity in-situ material concentration monitoring system suitable for deep space exploration missions according to claim 9, characterized in that: The laser beam enters the interior of the light spot array optical multi-pass pool through the small hole of the first high-reflection mirror at a certain angle, reaches the surface of the second high-reflection mirror, reaches the surface of the first high-reflection mirror after being reflected by the surface of the second high-reflection mirror, and then reaches the surface of the second high-reflection mirror after being reflected by the surface of the first high-reflection mirror. This process is repeated to form multiple reflections and then emitted from the small hole of the second high-reflection mirror; the distance between the first high-reflection mirror and the second high-reflection mirror of the light spot array optical multi-pass pool determines the distance of the light spot in the y-axis direction, thereby determining the certain angle.

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