Gas detection system and method

Abstract

The invention discloses a gas detection system and method. The gas detection system comprises a sample cell used for storing target gas, the cell wall is provided with a first group of light-transmitting windows and at least one second group of light-transmitting windows, and the second group of light-transmitting windows comprises a first light-transmitting window and a second light-transmitting window which are opposite to each other; the laser transmitter is used for transmitting laser to target gas through the first group of light-transmitting windows, so that the target gas generates Raman scattering light; the light condensation structure comprises a reflecting mirror and a convex lens, and the convex lens is used for focusing Raman scattering light scattered by the target gas to the second light-transmitting window and Raman scattering light reflected by the reflecting mirror at a focusing point; the optical fiber is used for receiving and transmitting the Raman scattering light; and the spectral imaging subsystem is used for generating a Raman spectrum based on the received Raman scattering light, and the Raman spectrum is used for detecting target parameters of the target gas. According to the embodiment of the invention, the collection efficiency of the gas Raman scattering light can be improved, and the collected gas Raman scattering light can be analyzed.

Description

Technical Field

[0001] The present application belongs to the field of gas detection technology, and in particular, relates to a gas detection system and method. Background Art

[0002] Raman spectroscopy is a scattering spectrum that characterizes the molecular structure of a substance. When the laser hits the sample, it will stimulate the Raman scattering signal of the sample molecules. Then, through components such as lenses or optical fibers, the light signal is collected into a spectrometer to analyze the Raman spectrum. Since the Raman scattering spectra of different gas molecules are different, the type and concentration of the gas can be qualitatively or quantitatively analyzed based on the Raman spectrum.

[0003] Raman light is a kind of scattered light, and the intensity of scattered light is positively correlated with the concentration of material molecules. Conventional Raman detection is mostly used for solids and liquids. However, since the density of gas is 1000 times lower than that of liquid, and the gas in industrial detection is generally a multi-component mixed gas, the concentration and content of the target gas may be 100 to 10,000 times lower, so the gas Raman signal is very weak, which limits the application of Raman spectroscopy in many gas detection industries. Summary of the invention

[0004] The embodiments of the present application provide a gas detection system and method, which can improve the collection efficiency of gas Raman scattered light and analyze the collected gas Raman scattered light.

[0005] In a first aspect, an embodiment of the present application provides a gas detection system, which includes: a sample pool, the sample pool is used to store target gas, a first group of light-transmitting windows and at least one second group of light-transmitting windows are arranged on the pool wall of the sample pool, the first group of light-transmitting windows includes two opposite light-transmitting windows, and the second group of light-transmitting windows includes a first light-transmitting window and a second light-transmitting window that are opposite; a laser emitter is used to emit a laser to the target gas in the sample pool through the first group of light-transmitting windows so that the target gas generates Raman scattered light; at least one focusing structure, the focusing structure includes a reflector and a convex lens, the reflector is located at the first light-transmitting window The convex lens is located outside the second light-transmitting window, and the reflecting surface of the reflector faces the first light-transmitting window, the convex lens is located outside the second light-transmitting window, and the convex lens is located on the optical path of the Raman scattered light reflected by the reflector, and the convex lens is used to focus the Raman scattered light scattered by the target gas toward the second light-transmitting window and the Raman scattered light reflected by the reflector at a focusing point; an optical fiber, the first end of the optical fiber is located at the focusing point, and the optical fiber is used to receive and transmit the Raman scattered light; a spectral imaging subsystem, the spectral imaging subsystem is connected to the second end of the optical fiber, the spectral imaging subsystem is used to generate a Raman spectrum based on the received Raman scattered light, and the Raman spectrum is used to detect the target parameters of the target gas.

[0006] According to the implementation of the first aspect of the present application, the sample pool is a closed polyhedron, the sample pool includes multiple groups of pool walls, each group of pool walls includes two opposite pool walls, and the first group of light-transmitting windows and the second group of light-transmitting windows are located on different groups of pool walls.

[0007] According to any of the aforementioned embodiments of the first aspect of the present application, the sample pool includes at least two second groups of light-transmitting windows, and the at least two second groups of light-transmitting windows are located on different groups of pool walls; the gas detection system includes at least two light-focusing structures, and the at least two light-focusing structures correspond one-to-one to the at least two second groups of light-transmitting windows, and the at least two light-focusing structures are used to focus the Raman scattered light passing through the at least two second groups of light-transmitting windows on different focusing points; the optical fiber includes at least two first ends, and the at least two first ends of the optical fiber are located at different focusing points, and the optical fiber is used to transmit the Raman scattered light received from the at least two focusing points to the spectral imaging subsystem.

[0008] According to any of the aforementioned embodiments of the first aspect of the present application, the optical fiber includes a first all-in-one optical fiber bundle, the first all-in-one optical fiber bundle includes at least two first ends and one second end, the at least two first ends of the first all-in-one optical fiber bundle are located at different focal points, the second end of the first all-in-one optical fiber bundle includes a multi-core optical fiber, the multi-core optical fibers are arranged linearly, and the second end of the first all-in-one optical fiber bundle is connected to the spectral imaging subsystem.

[0009] According to an embodiment of the first aspect of the present application, the optical fiber includes a preset number of first all-in-one optical fiber bundles and a second all-in-one optical fiber bundle, the first all-in-one optical fiber bundle includes at least two first ends and one second end, the at least two first ends of the first all-in-one optical fiber bundle are located at different focal points, the second all-in-one optical fiber bundle includes a preset number of first ends and one second end, the first ends of the second all-in-one optical fiber bundle are respectively connected to the second ends of the preset number of first all-in-one optical fiber bundles, the second end of the second all-in-one optical fiber bundle includes a multi-core optical fiber, the multi-core optical fibers are linearly arranged, and the second end of the second all-in-one optical fiber bundle is connected to the spectral imaging subsystem. According to any of the aforementioned embodiments of the first aspect of the present application, the focusing structure also includes: a collimator, the collimator is located on the optical path of the Raman scattered light reflected by the reflector, and is located between the second light-transmitting window and the convex lens.

[0010] According to any of the aforementioned embodiments of the first aspect of the present application, the spectral imaging subsystem includes: a spectrometer module, the spectrometer module is connected to the second end of the optical fiber, the spectrometer module is used to receive Raman scattered light transmitted by the optical fiber, and to split the Raman scattered light to obtain multiple optical signals; a detector, the detector is connected to the spectrometer module, and the detector is used to generate a Raman spectrum based on the multiple optical signals.

[0011] According to any of the aforementioned embodiments of the first aspect of the present application, the spectroscopic module includes a transmission grating, and / or the detector includes a planar array detector.

[0012] According to any of the aforementioned embodiments of the first aspect of the present application, the reflector includes a concave reflector, and the concave reflector is used to collect and reflect the Raman scattered light.

[0013] In a second aspect, an embodiment of the present application provides a gas detection method, which is applied to the gas detection system of the first aspect. The gas detection method includes: controlling a laser emitter to emit laser to a target gas in a sample pool through a first group of light-transmitting windows so that the target gas generates Raman scattered light; receiving the Raman scattered light from a focal point through an optical fiber; and generating a Raman spectrum based on the received Raman scattered light, wherein the Raman spectrum is used to detect target parameters of the target gas.

[0014] The gas detection system and method of the embodiment of the present application, by setting a first group of light-transmitting windows and at least one second group of light-transmitting windows on the wall of the sample pool, the first group of light-transmitting windows includes two opposite light-transmitting windows, and the second group of light-transmitting windows includes a first light-transmitting window and a second light-transmitting window opposite to each other, so that the laser emitter can irradiate the target gas in the sample pool through the first group of light-transmitting windows, so that the target gas generates Raman scattered light. Because the gas detection system includes at least one light-collecting structure, and the light-collecting structure includes a reflector and a convex lens, the reflector is located outside the first light-transmitting window, and the convex lens is located outside the second light-transmitting window, because the first light-transmitting window is opposite to the second light-transmitting window, and the convex lens is located on the optical path of the Raman scattered light reflected by the reflector, the convex lens can focus the Raman scattered light scattered by the target gas to the second light-transmitting window and the Raman scattered light reflected by the reflector at a focal point, so that the Raman scattered light at the focal point includes the Raman scattered light emitted to the first light-transmitting window and the Raman scattered light emitted to the second light-transmitting window, a total of two Raman scattered lights, thereby improving the gas Raman scattered light collection efficiency of the gas detection system. The gas detection system also includes an optical fiber, which receives and transmits Raman scattered light at a focus point through the optical fiber, and receives the Raman scattered light transmitted by the optical fiber through a spectral imaging subsystem to generate a Raman spectrum, thereby realizing the analysis of the Raman scattered light of the target gas using the Raman spectrum. BRIEF DESCRIPTION OF THE DRAWINGS

[0015] In order to more clearly illustrate the technical solution of the embodiments of the present application, the following is a brief introduction to the drawings required for use in the embodiments of the present application. For ordinary technicians in this field, other drawings can be obtained based on these drawings without any creative work.

[0016] Figure 1 is a structural schematic diagram of a gas detection system provided in an embodiment of the present application;

[0017] Figure 2 This is a schematic diagram of the structure of a sample pool provided in an embodiment of the present application;

[0018] Figure 3is another structural schematic diagram of a sample pool provided in an embodiment of the present application;

[0019] Figure 4 It is a structural schematic diagram of an optical fiber provided in an embodiment of the present application;

[0020] Figure 5 is another structural schematic diagram of the gas detection system provided in an embodiment of the present application;

[0021] Figure 6 is another structural schematic diagram of a gas detection system provided in an embodiment of the present application;

[0022] Figure 7 It is a flow chart of the gas detection method provided in the embodiment of the present application. DETAILED DESCRIPTION

[0023] The features and exemplary embodiments of various aspects of the present application will be described in detail below. In order to make the purpose, technical solutions and advantages of the present application clearer, the present application will be further described in detail below in conjunction with the accompanying drawings and specific embodiments. It should be understood that the specific embodiments described herein are only intended to explain the present application, rather than to limit the present application. For those skilled in the art, the present application can be implemented without the need for some of these specific details. The following description of the embodiments is only to provide a better understanding of the present application by illustrating the examples of the present application.

[0024] The acquisition, storage, use, and processing of data in the technical solution of this application comply with the relevant provisions of national laws and regulations.

[0025] It should be noted that, in this article, relational terms such as first and second, etc. are only used to distinguish one entity or operation from another entity or operation, and do not necessarily require or imply any such actual relationship or order between these entities or operations. Moreover, the terms "include", "comprise" or any other variants thereof are intended to cover non-exclusive inclusion, so that a process, method, article or device including a series of elements includes not only those elements, but also other elements not explicitly listed, or also includes elements inherent to such process, method, article or device. In the absence of further restrictions, the elements defined by the statement "include..." do not exclude the presence of other identical elements in the process, method, article or device including the elements.

[0026] It should be understood that the term "and / or" used in this article is only a description of the association relationship of associated objects, indicating that there can be three relationships. For example, A and / or B can represent: A exists alone, A and B exist at the same time, and B exists alone. In addition, the character " / " in this article generally indicates that the associated objects before and after are in an "or" relationship.

[0027] It is obvious to those skilled in the art that various modifications and changes can be made in the present application without departing from the spirit or scope of the present application. Therefore, the present application is intended to cover modifications and changes of the present application that fall within the scope of the corresponding claims (technical solutions for protection) and their equivalents. It should be noted that the implementation methods provided in the embodiments of the present application can be combined with each other without contradiction.

[0028] Gas Raman technology is commonly used in laboratory gas analysis and online gas detection in industries such as petrochemicals, fluorine chemicals, metallurgy and semiconductors. Since the gas Raman scattering spectrum signal is very weak, it is very important to improve the collection efficiency of the gas Raman signal.

[0029] Raman spectroscopy is a scattering spectrum that characterizes the molecular structure of a substance. When the laser hits the sample, it will stimulate the Raman scattering signal of the sample molecules. Then, through components such as lenses or optical fibers, the light signal is collected into a spectrometer to analyze the Raman spectrum. Since the Raman scattering spectra of different gas molecules are different, the type and concentration of the gas can be qualitatively or quantitatively analyzed based on the Raman spectrum.

[0030] Raman light is a kind of scattered light, and the intensity of scattered light is positively correlated with the concentration of material molecules. Conventional Raman detection is mostly used for solids and liquids. However, since the density of gas is 1000 times lower than that of liquid, and the gas in industrial detection is generally a multi-component mixed gas, the concentration and content of the target gas may be 100 to 10,000 times lower, so the gas Raman signal is very weak, which limits the application of Raman spectroscopy in many gas detection industries.

[0031] In order to improve the Raman signal of gas, the present application provides a gas Raman detection system and method to improve the collection efficiency of gas Raman scattered light. The following first introduces the gas Raman detection system provided in the embodiment of the present application.

[0032] Figure 1 Schematic diagram of a gas detection system provided in an embodiment of the present application. Figure 1 As shown, the gas detection system 100 may include: a sample pool 110 , a laser transmitter 120 , at least one focusing structure 130 , an optical fiber 140 and a spectral imaging subsystem 150 .

[0033] The sample pool 110 is used to store the target gas. A first group of light-transmitting windows and at least one second group of light-transmitting windows are arranged on the pool wall of the sample pool 110. The first group of light-transmitting windows includes two opposite light-transmitting windows a and b, and the second group of light-transmitting windows includes an opposite first light-transmitting window c and a second light-transmitting window d.

[0034] In some embodiments, the sample pool 110 is a closed polyhedron, and the sample pool 110 includes multiple groups of pool walls, each group of pool walls includes two opposite pool walls, and the first group of light-transmitting windows a and b and the second group of light-transmitting windows including c and e are located on different groups of pool walls. The target gas may include gases such as nitrogen and methane.

[0035] For example, Figure 2 As shown, Figure 2 It is a structural schematic diagram of a sample pool provided in an embodiment of the present application. The sample pool is in a cube shape and includes three groups of pool walls. Each group of pool walls includes two opposite pool walls. Each pool wall is provided with a light-transmitting window, and the two opposite light-transmitting windows form a group of light-transmitting windows. Laser light can be incident from one group of light-transmitting windows (the first group of light-transmitting windows) to excite the target gas in the sample pool to produce Raman scattered light. The sample pool body can be made of stainless steel or other corrosion-resistant alloy materials, and the light-transmitting window can be made of glass. The glass can be an optical grade adaptable or sapphire lens with high light transmittance and hardness. Inlet and outlet pipes can also be set on the sample pool to connect with the sample gas pipe.

[0036] Continue to see Figure 1 The laser emitter 120 is used to emit laser L to the target gas in the sample cell 110 through a in the first group of light-transmitting windows, so that the target gas generates Raman scattered light.

[0037] At least one focusing structure 130, the focusing structure 130 includes a reflector 131 and a convex lens 132, the reflector 131 is located outside the first light-transmitting window c, and the reflecting surface of the reflector 131 faces the first light-transmitting window c, the convex lens 132 is located outside the second light-transmitting window d, and the convex lens 132 is located on the optical path of the Raman scattered light reflected by the reflector 131, and the convex lens 132 is used to focus the Raman scattered light scattered by the target gas toward the second light-transmitting window and the Raman scattered light reflected by the reflector 131 at a focusing point e.

[0038] In some embodiments, the reflector 131 includes a concave reflector, and the concave reflector is used to collect and reflect the Raman scattered light.

[0039] When the laser L is irradiated on the target gas, the target gas generates Raman scattered light. The Raman scattering signal at the laser focus is the strongest. With the laser focus as the center of the sphere, the scattering direction of the Raman scattered light is distributed over the entire solid angle range. When the Raman scattered light is scattered toward the first light-transmitting window c, it will be reflected back by the reflector 131 outside the first light-transmitting window. At the same time, the Raman scattered light will also be scattered toward the second light-transmitting window d. Since the first light-transmitting window c is opposite to the second light-transmitting window d, the Raman scattered light reflected by the reflector 131 will be combined with the Raman scattered light originally scattered toward the second light-transmitting window, and pass through the second light-transmitting window d together to reach the convex lens 132. In this way, the Raman scattered light reaching the convex lens 132 is changed from one path to two paths, and then converged to the focal point through the convex lens 132, so that the Raman scattered light at the focal point is twice the original, thereby improving the collection efficiency of the Raman scattered light.

[0040] The optical fiber 140 has a first end located at the focusing point e, and the optical fiber 140 is used to receive and transmit Raman scattered light.

[0041] The optical fiber 140 may have various structures, see Figure 4 Partial detailed explanation.

[0042] The spectral imaging subsystem 150 is connected to the second end of the optical fiber 140 . The spectral imaging subsystem 150 is used to generate a Raman spectrum based on the received Raman scattered light. The Raman spectrum is used to detect the target parameters of the target gas.

[0043] In some embodiments, the spectral imaging subsystem 150 may include: a spectroscopic module and a detector.

[0044] The light splitting module is connected to the second end of the optical fiber, and is used for receiving the Raman scattered light transmitted by the optical fiber and splitting the Raman scattered light to obtain a plurality of optical signals.

[0045] The detector is connected to the spectroscopic module, and the detector is used to generate a Raman spectrum according to a plurality of optical signals.

[0046] In some embodiments, the spectral imaging subsystem includes a transmission spectrometer, the spectroscopic module includes a transmission grating, and / or the detector includes a planar array detector. The transmission spectrometer has the following characteristics: the inlet is a linearly arranged multi-core optical fiber, which can adapt to the structure of the optical fiber 140; the transmission spectrometer uses a high numerical aperture value (NA) and a high transmittance transmission optical path inside, which can completely transmit the signal of the optical fiber to the detector. The detector includes a planar array detector, which has a certain longitudinal height, and the longitudinal pixels are generally 64 / 128 / 256. The photosensitivity height is usually 3mm or higher to fully receive the signals of multiple optical fibers.

[0047] The gas detection system of the embodiment of the present application is provided with a first group of light-transmitting windows and at least one second group of light-transmitting windows on the wall of the sample pool, wherein the first group of light-transmitting windows includes two opposite light-transmitting windows, and the second group of light-transmitting windows includes a first light-transmitting window and a second light-transmitting window opposite to each other, so that the laser emitter can irradiate the target gas in the sample pool through the first group of light-transmitting windows, thereby causing the target gas to generate Raman scattered light. Because the gas detection system includes at least one light-focusing structure, and the light-focusing structure includes a reflector and a convex lens, the reflector is located outside the first light-transmitting window, and the convex lens is located outside the second light-transmitting window, since the first light-transmitting window is opposite to the second light-transmitting window, and the convex lens is located on the optical path of the Raman scattered light reflected by the reflector, the convex lens can focus the Raman scattered light scattered by the target gas to the second light-transmitting window and the Raman scattered light reflected by the reflector at a focal point, so that the Raman scattered light at the focal point includes the Raman scattered light emitted to the first light-transmitting window and the Raman scattered light emitted to the second light-transmitting window, a total of two Raman scattered lights, thereby improving the gas Raman scattered light collection efficiency of the gas detection system. The gas detection system also includes an optical fiber, which receives and transmits Raman scattered light at a focus point through the optical fiber, and receives the Raman scattered light transmitted by the optical fiber through a spectral imaging subsystem to generate a Raman spectrum, thereby realizing the analysis of the Raman scattered light of the target gas using the Raman spectrum.

[0048] In some embodiments, the sample pool includes at least two second groups of light-transmitting windows, and the at least two second groups of light-transmitting windows are located on different groups of pool walls, such as Figure 3 As shown, Figure 3 It is another structural schematic diagram of the sample pool provided in an embodiment of the present application, which is a top-down cross-sectional view when the sample pool is a cube, and the center is the laser L incident from top to bottom. The gas detection system includes at least two focusing structures, 130 and 130', respectively. The at least two focusing structures correspond one-to-one to at least two second groups of light-transmitting windows. The at least two focusing structures are used to focus the Raman scattered light passing through the at least two second groups of light-transmitting windows on different focal points, namely, focal point 1 and focal point 2; the optical fiber includes at least two first ends, and the at least two first ends of the optical fiber are located at different focal points, that is, the two first ends of the optical fiber are located at focal point 1 and focal point 2, respectively; the optical fiber is used to transmit the Raman scattered light received from the at least two focusing points to the spectral imaging subsystem.

[0049] Figure 3The example shows a case where the sample pool is in a cube shape and Raman scattered light is collected in two ways and four directions. In this case, the collected Raman scattered light is four times that collected in one direction. In other embodiments, the sample pool may be in a three-dimensional shape with six sides. In this case, there may be three focusing structures, each of which focuses the Raman scattered light transmitted through the light-transmitting window at three different focusing points. The three first ends of the optical fiber are respectively placed at the three focusing points, so that the optical fiber can transmit the Raman scattered light to the spectroscopic module. In this case, the sample pool can be collected in three ways and six directions, and the collected Raman scattered light is six times that collected in one direction.

[0050] By improving the collection efficiency of gas Raman scattered light, the sensitivity and signal-to-noise ratio of the spectral signal can be improved, thereby improving the device's ability to detect low-concentration gases.

[0051] Figure 4 is a schematic diagram of the structure of an optical fiber provided in an embodiment of the present application, such as Figure 4 As shown, the optical fiber includes a first all-in-one optical fiber bundle, the first all-in-one optical fiber bundle includes at least two first ends and one second end, and the at least two first ends of the first all-in-one optical fiber bundle are located at different focusing points. Figure 4 The end face enlarged view of the first end and the end face enlarged view of the second end of the first all-in-one optical fiber bundle are shown. The second end of the first all-in-one optical fiber bundle includes a multi-core optical fiber, and the multi-core optical fiber is arranged linearly. The second end of the first all-in-one optical fiber bundle is connected to the spectral imaging subsystem. Therefore, in some embodiments, the spectral imaging subsystem needs to use a transmission spectrometer because the inlet of the transmission spectrometer is a linearly arranged multi-core optical fiber.

[0052] Combination Figure 3 and Figure 4 Come and see, Figure 3 In the embodiment, there are two focusing points, namely focusing point 1 and focusing point 2. Figure 4 The first multi-in-one optical fiber bundle has multiple first ends. When it is a two-in-one optical fiber bundle, the optical fiber can use a 2*50 optical fiber. The two first ends of the two-in-one optical fiber bundle are respectively placed at focusing point 1 and focusing point 2 to collect two Raman scattered lights and finally gather them together. This is equivalent to collecting four paths of gas Raman scattered light, which greatly improves the collection efficiency of gas Raman scattered light.

[0053] In other embodiments, the optical fiber includes a preset number of first all-in-one optical fiber bundles and a second all-in-one optical fiber bundle, the first all-in-one optical fiber bundle includes at least two first ends and a second end, the at least two first ends of the first all-in-one optical fiber bundle are located at different focal points, the second all-in-one optical fiber bundle includes a preset number of first ends and a second end, the first ends of the second all-in-one optical fiber bundle are respectively connected to the second ends of the preset number of first all-in-one optical fiber bundles, the second end of the second all-in-one optical fiber bundle includes multi-core optical fibers, the multi-core optical fibers are linearly arranged, and the second end of the second all-in-one optical fiber bundle is connected to the spectral imaging subsystem. That is, multiple all-in-one optical fiber bundles can be combined together through a new all-in-one optical fiber bundle.

[0054] Exemplarily, when the sample pool is irradiated with laser and focused by the focusing structure, there are eight focusing points. A four-in-one fiber optic bundle can be used for each of the four focusing points. The first ends of the four-in-one fiber optic bundles are respectively located at different focusing points. A total of two four-in-one fiber optic bundles are used. The two four-in-one fiber optic bundles can be connected by a two-in-one fiber optic bundle. The two-in-one fiber optic bundle has two first ends, which are respectively connected to the second ends of the two four-in-one fiber optic bundles. The two-in-one fiber optic bundle will eventually transmit the collected Raman scattered light from the eight focusing points to the spectrometer module.

[0055] In some embodiments, the light focusing structure 130 may further include: a collimator 133, such as Figure 5 As shown, Figure 5 This is another structural schematic diagram of the gas detection system provided in an embodiment of the present application. The collimator 133 is located on the optical path of the Raman scattered light reflected by the reflector 131 and is located between the second light-transmitting window d and the convex lens 132 .

[0056] The purpose of the collimator is to make the Raman scattered light emitted from the sample cell 110 straight, which is more conducive to the focusing of the convex lens.

[0057] Figure 6 is another structural schematic diagram of the gas detection system provided in the embodiment of the present application, such as Figure 6As shown, the sample pool is in the shape of a cube, and the laser L is incident into the sample pool from top to bottom. After the target gas in the sample pool is irradiated by the laser, it generates scattered Raman scattered light. The focusing structure 130 includes a reflector 131, a collimator 133 and a convex lens 132. Under the action of the focusing structure 130, the two Raman scattered lights are focused on the focal point 1. The focusing structure 130' includes a reflector 131', a collimator 133' and a convex lens 132'. Under the action of the focusing structure 130', the two Raman scattered lights are focused on the focal point 2. Then, through the optical fiber, the optical fiber includes a two-in-one optical fiber bundle, and the two first ends of the two-in-one optical fiber bundle are respectively located at the focal point 1 and the focal point 2, and the Raman scattered light is transmitted to the second end of the two-in-one optical fiber bundle, and the second end of the two-in-one optical fiber bundle is a linearly arranged multi-core optical fiber. The four Raman scattered lights are gathered together by the two-in-one optical fiber bundle, and the collection efficiency of the Raman scattered light is increased by four times, and then injected into the spectral imaging subsystem 150. The spectral imaging subsystem 150 may include a spectroscopic module and an array detector. The four-path Raman scattered light generates a Raman spectrum in the spectral imaging subsystem. The Raman spectrum is used to detect target parameters of the target gas, such as the type and concentration of the gas.

[0058] Based on the same technical concept as the gas detection system provided in the above embodiment, the present application also provides a gas detection method. Please see the following embodiment.

[0059] Figure 7 is a flow chart of a gas detection method provided in an embodiment of the present application, such as Figure 7 As shown, the gas detection method 700 may include: S701 to S703.

[0060] S701, controlling the laser emitter to emit laser to the target gas in the sample cell through the first group of light-transmitting windows, so that the target gas generates Raman scattered light.

[0061] S702, receiving Raman scattered light at the focus point through the optical fiber.

[0062] S703 . Generate a Raman spectrum based on the received Raman scattered light, where the Raman spectrum is used to detect target parameters of the target gas.

[0063] The gas detection method of the embodiment of the present application controls the laser emitter to irradiate the target gas in the sample pool through the first group of light-transmitting windows, so that the target gas generates Raman scattered light. Because the gas detection system used in the gas detection method includes at least one light-focusing structure, and the light-focusing structure includes a reflector and a convex lens, the reflector is located outside the first light-transmitting window, and the convex lens is located outside the second light-transmitting window. Since the first light-transmitting window is opposite to the second light-transmitting window, and the convex lens is located on the optical path of the Raman scattered light reflected by the reflector, the convex lens can focus the Raman scattered light scattered by the target gas to the second light-transmitting window and the Raman scattered light reflected by the reflector at the focal point, so that the Raman scattered light at the focal point includes the Raman scattered light emitted to the first light-transmitting window and the Raman scattered light emitted to the second light-transmitting window, a total of two Raman scattered lights, which improves the gas Raman scattered light collection efficiency of the gas detection system. The Raman scattered light at the focal point is received and transmitted by the optical fiber, and the Raman scattered light transmitted by the optical fiber is received by the spectral imaging subsystem to generate a Raman spectrum, thereby realizing the analysis of the Raman scattered light of the target gas using the Raman spectrum.

[0064] It should be clear that the present application is not limited to the specific configuration and processing described above and shown in the figures. For the sake of simplicity, a detailed description of the known method is omitted here. In the above embodiments, several specific steps are described and shown as examples. However, the method process of the present application is not limited to the specific steps described and shown, and those skilled in the art can make various changes, modifications and additions, or change the order between the steps after understanding the spirit of the present application.

[0065] The functional blocks shown in the structural block diagram described above can be implemented as hardware, software, firmware or a combination thereof. When implemented in hardware, it can be, for example, an electronic circuit, an application-specific integrated circuit (Application Specific Integrated Circuit, ASIC), appropriate firmware, plug-in, function card, etc. When implemented in software, the elements of the present application are programs or code segments used to perform the required tasks. The program or code segment can be stored in a machine-readable medium, or transmitted on a transmission medium or communication link by a data signal carried in a carrier. "Machine-readable medium" can include any medium capable of storing or transmitting information. Examples of machine-readable media include electronic circuits, semiconductor memory devices, read-only memory (Read-Only Memory, ROM), flash memory, erasable read-only memory (Erasable ReadOnly Memory, EROM), floppy disks, compact disc read-only memory (Compact Disc Read-Only Memory, CD-ROM), optical discs, hard disks, optical fiber media, radio frequency (Radio Frequency, RF) links, etc. The code segment can be downloaded via a computer network such as the Internet, an intranet, etc.

[0066] It should also be noted that the exemplary embodiments mentioned in this application describe some methods or systems based on a series of steps or devices. However, this application is not limited to the order of the above steps, that is, the steps can be performed in the order mentioned in the embodiment, or in a different order from the embodiment, or several steps can be performed simultaneously.

[0067] Aspects of the present disclosure are described above with reference to the flowchart and / or block diagram of the method, device (system) and computer program product according to the embodiment of the present disclosure. It should be understood that each box in the flowchart and / or block diagram and the combination of each box in the flowchart and / or block diagram can be implemented by computer program instructions. These computer program instructions can be provided to a processor of a general-purpose computer, a special-purpose computer, or other programmable data processing device to produce a machine so that these instructions executed by the processor of the computer or other programmable data processing device enable the implementation of the function / action specified in one or more boxes of the flowchart and / or block diagram. Such a processor can be, but is not limited to, a general-purpose processor, a special-purpose processor, a special application processor, or a field programmable logic circuit. It can also be understood that each box in the block diagram and / or flowchart and the combination of boxes in the block diagram and / or flowchart can also be implemented by dedicated hardware that performs a specified function or action, or can be implemented by a combination of dedicated hardware and computer instructions.

[0068] The above is only a specific implementation of the present application. Those skilled in the art can clearly understand that for the convenience and simplicity of description, the specific working processes of the systems, modules and units described above can refer to the corresponding processes in the aforementioned method embodiments, and will not be repeated here. It should be understood that the protection scope of the present application is not limited to this. Any technician familiar with the technical field can easily think of various equivalent modifications or replacements within the technical scope disclosed in this application, and these modifications or replacements should be included in the protection scope of this application.

Claims

1. A gas detection system, characterized in that: include: A sample pool, the sample pool is used to store the target gas, a first group of light-transmitting windows and at least one second group of light-transmitting windows are arranged on the pool wall of the sample pool, the first group of light-transmitting windows includes two opposite light-transmitting windows, and the second group of light-transmitting windows includes a first light-transmitting window and a second light-transmitting window that are opposite to each other; A laser emitter, used for emitting laser light to the target gas in the sample cell through the first group of light-transmitting windows, so that the target gas generates Raman scattered light; at least one light-focusing structure, the light-focusing structure comprising a reflector and a convex lens, the reflector being located outside the first light-transmitting window, and the reflective surface of the reflector facing the first light-transmitting window, the convex lens being located outside the second light-transmitting window, and the convex lens being located on the optical path of the Raman scattered light reflected by the reflector, the convex lens being used to focus the Raman scattered light scattered by the target gas toward the second light-transmitting window and the Raman scattered light reflected by the reflector at a focusing point; An optical fiber, wherein a first end of the optical fiber is located at the focusing point, and the optical fiber is used to receive and transmit the Raman scattered light; A spectral imaging subsystem is connected to the second end of the optical fiber, and is used to generate a Raman spectrum based on the received Raman scattered light, and the Raman spectrum is used to detect the target parameter of the target gas.

2. The gas detection system according to claim 1, characterized in that: The sample pool is a closed polyhedron, comprising a plurality of groups of pool walls, each group of pool walls comprising two opposite pool walls, and the first group of light-transmitting windows and the second group of light-transmitting windows are located on different groups of pool walls.

3. The gas detection system according to claim 2, characterized in that: The sample pool comprises at least two of the second light-transmitting windows, and at least two of the second light-transmitting windows are located on different groups of pool walls; The gas detection system comprises at least two light-focusing structures, the at least two light-focusing structures correspond to at least two of the second light-transmitting windows in one-to-one correspondence, and the at least two light-focusing structures are used to focus the Raman scattered light passing through the at least two second light-transmitting windows at different focal points; The optical fiber includes at least two first ends, the at least two first ends of the optical fiber are located at different focusing points, and the optical fiber is used to transmit the Raman scattered light received from at least two focusing points to the spectral imaging subsystem.

4. The gas detection system according to claim 3, characterized in that: The optical fiber includes a first all-in-one optical fiber bundle, which includes at least two first ends and one second end, the at least two first ends of the first all-in-one optical fiber bundle are located at different focusing points, the second end of the first all-in-one optical fiber bundle includes a multi-core optical fiber, the multi-core optical fibers are arranged linearly, and the second end of the first all-in-one optical fiber bundle is connected to the spectral imaging subsystem.

5. The gas detection system according to claim 3, characterized in that: The optical fiber includes a preset number of first all-in-one optical fiber bundles and a second all-in-one optical fiber bundle, the first all-in-one optical fiber bundle includes at least two first ends and one second end, the at least two first ends of the first all-in-one optical fiber bundle are located at different focusing points, the second all-in-one optical fiber bundle includes the preset number of first ends and one second end, the first ends of the second all-in-one optical fiber bundle are respectively connected to the preset number of second ends of the first all-in-one optical fiber bundles, the second end of the second all-in-one optical fiber bundle includes multi-core optical fibers, the multi-core optical fibers are arranged linearly, and the second end of the second all-in-one optical fiber bundle is connected to the spectral imaging subsystem.

6. The gas detection system according to claim 1, characterized in that: The light focusing structure further comprises: A collimator is located on the optical path of the Raman scattered light reflected by the reflector and between the second light-transmitting window and the convex lens.

7. The gas detection system according to claim 1, characterized in that: The spectral imaging subsystem comprises: a light splitting module connected to the second end of the optical fiber, and configured to receive the Raman scattered light transmitted by the optical fiber and split the Raman scattered light to obtain a plurality of optical signals; A detector is connected to the light splitting module, and is used to generate a Raman spectrum according to the multiple optical signals.

8. The gas detection system according to claim 7, characterized in that: The spectroscopic module includes a transmission grating, and / or the detector includes a planar array detector.

9. The gas detection system according to claim 1, characterized in that: The reflector includes a concave reflector, and the concave reflector is used to collect and reflect the Raman scattered light.

10. A gas detection method, characterized in that: Applied to the gas detection system according to any one of claims 1 to 9, the method comprising: Controlling a laser emitter to emit laser light toward the target gas in the sample cell through the first group of light-transmitting windows, so that the target gas generates Raman scattered light; receiving Raman scattered light at the focus point through an optical fiber; Based on the received Raman scattered light, a Raman spectrum is generated, and the Raman spectrum is used to detect a target parameter of the target gas.

Images