Gas detection instrument feedback system and method with fast response time

Abstract

The invention relates to the technical field of gas detectors, in particular to a gas detector feedback system and method with fast response time, and the system and method comprise the following steps: a monitoring unit collects environment humidity in real time, and collects a surface image of an infrared sensor according to the environment humidity; the water film analysis unit determines whether a water film is distributed on the surface of the infrared sensor according to the surface image and determines the water film thickness and the water film distribution state; the absorption analysis unit determines the refraction influence degree of the environment humidity on the refractive index according to the environment humidity, the water film thickness and the water film distribution state; and the execution unit judges whether the surface of the infrared sensor is erased or not based on the refraction influence degree, and determines the water film erasing frequency according to the judgment result. According to the invention, environmental influence factors are considered, the interference of a water film and water vapor on infrared ray propagation is reduced, the response time of gas detection is effectively shortened, and the accuracy and reliability of detection are improved.

Description

Technical Field

[0001] The present invention relates to the technical field of gas detectors, and particularly to a feedback system and method for a gas detection instrument with a fast response time. Background Art

[0002] An infrared gas detector is an instrument that uses the principle of infrared spectral absorption to detect the components and concentrations of gases. Due to differences in structure and chemical bonds, different gas molecules have different infrared absorption spectra. When infrared light passes through a gas medium, gas molecules will absorb the energy of infrared light at specific wavelengths, causing the infrared light to attenuate, and thus obtaining the gas concentration.

[0003] The response time and feedback of an infrared gas detector are mainly affected by aspects such as the performance of the instrument itself, detection environmental conditions, and gas characteristics. For example, changes in environmental humidity may cause changes in the refractive index of the medium in the optical path, affecting the propagation path and intensity of infrared light. At the same time, in a high-humidity environment, tiny water droplets or water films may form on the surface of optical components, scattering or absorbing light, interfering with the detection of the characteristic spectrum of the target gas, and causing the detector to take longer to accurately identify and analyze signals, thereby prolonging the response time.

[0004] Therefore, there is an urgent need for a feedback system and method for a gas detection instrument with a fast response time, which can improve the response speed of an infrared gas detector and at the same time improve the accuracy of detecting gas concentration. Summary of the Invention

[0005] For this purpose, the present invention provides a feedback system and method for a gas detection instrument with a fast response time to overcome the problem that the influence of environmental humidity and water films on the surface of optical components on the refraction of infrared rays is not considered when an infrared gas detector detects gases in the prior art.

[0006] To achieve the above object, on the one hand, the present invention provides a feedback system for a gas detection instrument with a fast response time, including:

[0007] A monitoring unit, which is used to collect the environmental humidity in real time and collect the surface image of an infrared sensor according to the environmental humidity;

[0008] A water film analysis unit, which is connected to the monitoring unit and is used to determine whether there is a water film distribution on the surface of the infrared sensor according to the surface image, and determine the water film thickness and water film distribution state;

[0009] An absorption analysis unit, which is connected to the monitoring unit and the water film analysis unit and is used to determine the degree of refraction influence of environmental humidity on the refractive index according to the environmental humidity, water film thickness, and water film distribution state;

[0010] An execution unit, connected to the absorption analysis unit, determines whether to perform an erasing process on the surface of the infrared sensor based on the degree of refraction influence, and determines the water film erasing frequency according to the determination result.

[0011] As a preferred technical solution of a gas detection instrument feedback system with fast response time, the water film analysis unit determines the water film area and non-water film area on the surface of the infrared sensor according to the surface image, divides the water film area into several water film sub-areas, and determines the water film thickness and water film distribution state in each water film sub-area.

[0012] As a preferred technical solution of a gas detection instrument feedback system with fast response time, the absorption analysis unit determines the degree of water vapor influence of water vapor in the environment on the refractive index of infrared rays according to the environmental humidity, and determines the degree of water film influence of the water film on the surface of the infrared sensor on the refractive index of infrared rays according to the water film thickness and water film distribution state, and, determines the degree of refraction influence according to the degree of water vapor influence, the degree of water film influence and the water film thickness.

[0013] As a preferred technical solution of a gas detection instrument feedback system with fast response time, the absorption analysis unit compares the environmental humidity with a preset humidity range to determine the deviation degree of the environmental humidity, and determines the degree of water vapor influence based on the deviation degree.

[0014] As a preferred technical solution of a gas detection instrument feedback system with fast response time, the water film analysis unit includes a machine learning model, and the machine learning model is used to determine the water film distribution state according to the surface image to determine the degree of water film influence;

[0015] Wherein, the water film distribution state includes a uniform state, a non-uniform state and a state without a water film.

[0016] As a preferred technical solution of a gas detection instrument feedback system with fast response time, the absorption analysis unit determines the degree of water film influence according to the water film distribution state, including:

[0017] If the water film distribution state is a uniform state, it is determined to determine the propagation speed of infrared rays in the water film based on the water film thickness, and determine the degree of water film influence based on the propagation speed;

[0018] If the water film distribution state is a non-uniform state, it is determined to determine the water-gas ratio based on the water film distribution state, and determine the degree of water film influence by combining the water film refractive index and the air refractive index;

[0019] If the water film distribution state is a state without a water film, the degree of water film influence is 0.

[0020] As a preferred technical solution of a feedback system for a gas detection instrument with a fast response time, the absorption analysis unit determines the water film contribution ratio and the water vapor contribution ratio of the infrared refractive index by the water film and water vapor respectively based on the comparison result between the water film thickness and a preset thickness, so as to weight the influence degree of the water film and the influence degree of the water vapor respectively, and determine the refraction influence degree according to the sum of the weighted influence degree of the water film and the weighted influence degree of the water vapor.

[0021] As a preferred technical solution of a feedback system for a gas detection instrument with a fast response time, the absorption analysis unit configures the relationship between the water film contribution ratio and the water vapor contribution ratio based on the water film thickness, including:

[0022] If the water film thickness is less than or equal to the preset thickness, then the water vapor contribution ratio is constrained to be greater than the water film contribution ratio;

[0023] If the water film thickness is greater than the preset thickness, then the water film contribution ratio is constrained to be greater than the water vapor contribution ratio.

[0024] As a preferred technical solution of a feedback system for a gas detection instrument with a fast response time, the execution unit determines whether to perform an erasing process on the surface of the infrared sensor based on the refraction influence degree, and determines the water film erasing frequency according to the determination result, including:

[0025] If the refraction influence degree is less than the preset influence degree, then no erasing process is performed;

[0026] If the refraction influence degree is greater than or equal to the preset influence degree, then an erasing process is performed, and the water film erasing frequency is determined according to the refraction influence degree and the preset influence degree.

[0027] On the other hand, the present invention also provides a method applied to a feedback system for a gas detection instrument with a fast response time, including:

[0028] Real-time collect the environmental humidity, and collect the surface image of the infrared sensor according to the environmental humidity;

[0029] Determine whether there is a water film distribution on the surface of the infrared sensor according to the surface image, and determine the water film thickness and the water film distribution state;

[0030] Determine the refraction influence degree of the environmental humidity on the refractive index according to the environmental humidity, the water film thickness and the water film distribution state;

[0031] Determine whether to perform an erasing process on the surface of the infrared sensor based on the refraction influence degree, and determine the water film erasing frequency according to the determination result.

[0032] Compared with the prior art, the beneficial effects of the present invention are as follows. When the present invention performs gas detection, it determines the water film thickness and the water film distribution state by collecting the surface image of the infrared sensor; at the same time, based on the environmental humidity, the water film thickness and the water film distribution state, it determines the refractive influence degree of the environmental humidity on the refractive index to determine whether it is necessary to perform an erasing process on the surface of the infrared sensor, and determines the water film erasing frequency, reduces the influence of the water vapor water film on the infrared propagation, and at the same time avoids the increase in the signal processing time caused by the distortion of the infrared absorption signal, improves the response speed of the gas detector, and further improves the detection accuracy of the gas concentration.

[0033] In particular, the absorption analysis unit of the present invention determines the influence degree of water vapor according to the environmental humidity, and determines the influence degree of the water film based on the water film thickness and the water film distribution state, so as to determine the overall refractive influence degree of the environment on the infrared ray, and provides a reasonable basis for whether to perform an erasing process and determining the water film erasing frequency subsequently, thereby further helping to accelerate the response speed of the gas detector and improve the detection accuracy.

[0034] In particular, the absorption analysis unit of the present invention determines the water film contribution ratio and the water vapor contribution ratio of the water film and the water vapor to the refractive index of the infrared ray respectively based on the comparison result between the water film thickness and the preset thickness to determine the refractive influence degree. While determining the overall influence of the environment on the refractive index, it provides a reasonable basis for whether to perform an erasing process and determining the water film erasing frequency subsequently, thereby further helping to accelerate the response speed of the gas detector and improve the detection accuracy.

[0035] In particular, the execution unit of the present invention determines the water film erasing frequency based on the refractive influence degree, reduces the interference of the water film water vapor on the infrared ray, promotes the gas to be detected to pass through the detection area faster, reduces the infrared ray refraction fluctuation caused by the water film water vapor, accelerates the response speed of the gas detector and makes the detection signal more stable, and improves the detection accuracy. Description of the Drawings

[0036] Figure 1 It is a structural block diagram of the gas detection instrument feedback system according to the embodiment of the present invention;

[0037] Figure 2 It is a step diagram for determining the refractive influence degree according to the embodiment of the present invention;

[0038] Figure 3 It is a step diagram for determining the influence degree of the water film according to the embodiment of the present invention;

[0039] Figure 4 It is a step diagram of the method applied to the gas detection instrument feedback system according to the embodiment of the present invention. Detailed Embodiments

[0040] In order to make the objectives and advantages of the present invention more clear and understandable, the present invention will be further described below in conjunction with embodiments; it should be understood that the specific embodiments described herein are only used to explain the present invention and are not used to limit the present invention.

[0041] The preferred embodiments of the present invention will be described below with reference to the accompanying drawings. Those skilled in the art should understand that these embodiments are only used to explain the technical principles of the present invention and do not limit the protection scope of the present invention.

[0042] It should be noted that in the description of the present invention, the terms indicating directions or positional relationships such as "upper", "lower", "left", "right", "inner", "outer", etc. are based on the directions or positional relationships shown in the drawings. This is only for convenience of description and does not indicate or imply that the device or element must have a specific orientation, be constructed and operated in a specific orientation, and therefore should not be construed as a limitation of the present invention.

[0043] In addition, it should also be noted that in the description of the present invention, unless otherwise clearly specified and limited, the terms "installation", "connection", and "coupling" 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 directly connected or indirectly connected through an intermediate medium, and it can be the communication inside two elements. For those skilled in the art, the specific meanings of the above terms in the present invention can be understood according to specific circumstances.

[0044] Please refer to Figure 1 as shown, which is the structural block diagram of the feedback system of the gas detection instrument according to the embodiment of the present invention; specifically, the present invention provides a feedback system of a gas detection instrument with a fast response time, including:

[0045] A monitoring unit, which is used to collect the ambient humidity in real time and collect the surface image of the infrared sensor according to the ambient humidity;

[0046] A water film analysis unit, which is connected to the monitoring unit and is used to determine whether there is a water film distribution on the surface of the infrared sensor according to the surface image, and determine the water film thickness and the water film distribution state;

[0047] An absorption analysis unit, which is connected to the monitoring unit and the water film analysis unit and is used to determine the refractive influence degree of the ambient humidity on the refractive index according to the ambient humidity, the water film thickness and the water film distribution state;

[0048] An execution unit, which is connected to the absorption analysis unit, determines whether to perform an erasing process on the surface of the infrared sensor based on the refractive influence degree, and determines the water film erasing frequency according to the determination result.

[0049] Specifically, different gas molecules have different absorption degrees for specific infrared wavelengths. An infrared gas detector uses an infrared sensor to measure the absorption degree of the gas to be detected for a specific infrared wavelength to detect the gas concentration, and the gas concentration is proportional to the intensity of the absorbed light. When the humidity of the gas concentration detection environment is relatively high, both the environmental humidity and the water film on the surface of the infrared sensor will affect the response time of the gas detector. The presence of the water film and water vapor will change the refractive index of the infrared propagation medium. Under different humidity, water film thickness and distribution states, the degree of refractive index change is different. When the influence degree is relatively large, it means that the environmental humidity is high, the water film on the surface of the infrared sensor is thicker or more widely distributed. The water film on the surface of the infrared sensor will additionally absorb and scatter infrared rays. When the infrared rays pass through the water film, part of its energy will be absorbed by the water film, resulting in a reduction in the effective infrared energy reaching the sensor for gas detection, increasing the gas transmission distance and difficulty, leading to an increase in the distortion degree of the detection signal, a decrease in the accuracy of the detection result, and an extension of the response time.

[0050] Specifically, the environmental humidity is essentially the water vapor content in the air. When the environmental humidity is high, a large number of water vapor molecules occupy a certain space, hindering the diffusion of the gas molecules to be measured, resulting in an extension of the time for the gas to reach the infrared sensor, and thus affecting the response time of the detector. At the same time, the water film on the surface of the infrared sensor will additionally absorb and scatter infrared rays. When the infrared rays pass through the water film, part of its energy will be absorbed by the water film, resulting in a reduction in the effective infrared energy reaching the sensor for gas detection, and increasing the gas transmission distance and difficulty. In order to accurately detect the absorption change of the gas to infrared light, the sensor needs a longer time to accumulate sufficient signals, which will also increase the response time. Therefore, in practice, erasing the water film on the surface of the infrared sensor can reduce the influence of environmental humidity on infrared rays and the response time of the gas detector.

[0051] In practice, when the environmental humidity is greater than the preset humidity threshold, it indicates that the environmental humidity is too high and there is water vapor distribution in the air, and it is easy to have water vapor condensation on the surface of the infrared sensor. Therefore, the surface image of the infrared sensor is collected. The value range of the preset humidity threshold is 65%RH - 70%RH. Preferably, the value of the preset humidity threshold is 68%RH.

[0052] In the above embodiment, when the present invention performs gas detection, it determines the water film thickness and water film distribution state by collecting the surface image of the infrared sensor; at the same time, based on the environmental humidity, water film thickness and water film distribution state, it determines the refractive influence degree of the environmental humidity on the refractive index to determine whether it is necessary to perform an erasing process on the surface of the infrared sensor, and determines the water film erasing frequency, reducing the influence of water vapor and water film on infrared propagation, and at the same time avoiding an increase in the signal processing time caused by the distortion of the infrared absorption signal, improving the response speed of the gas detector, and further improving the accuracy of detecting the gas concentration.

[0053] Specifically, the water film analysis unit determines the water film area and the non-water film area on the surface of the infrared sensor according to the surface image, and divides the water film area into several water film sub-areas, so as to determine the water film thickness and the water film distribution state in each water film sub-area.

[0054] In detail, there will be a certain difference in grayscale between the water film area and the non-water film area. The water film may cause changes such as surface reflection, resulting in a different grayscale from the non-water film area. At the same time, areas with a thicker water film may cause more light attenuation, and the grayscale value is also different from that of areas with a thinner water film. Therefore, the change trend of the water film thickness can be judged by analyzing the change of the grayscale value in the water film area, and the water film distribution state can be determined.

[0055] In implementation, the water film analysis unit processes the surface image based on a preset machine learning model, uses a threshold segmentation algorithm to divide the surface image into a water film area and a non-water film area, and clusters similar pixel points according to the grayscale value of the water film area, so as to realize dividing the water film area into several water film sub-areas. The clustering algorithm can be the K-Means clustering algorithm. According to the Beer-Lambert law, the infrared light intensity has an exponential relationship with the water film thickness. Therefore, a mathematical model I = I 0 e -kd can be established, where I is the infrared light intensity transmitted through the water film, I 0 is the incident infrared light intensity, k is a constant related to the optical properties of water, and d is the water film thickness. According to this mathematical model, the water film thickness in the water film sub-area can be determined, and the water film distribution state can be obtained, which includes a uniform state and a non-uniform state. If there is a non-water film area in the surface image, it is marked as a non-uniform state; if there is no non-water film area in the surface image, it is marked as a uniform state.

[0056] In the above embodiment, the absorption analysis unit of the present invention determines the degree of influence of water vapor according to the environmental humidity, and determines the degree of influence of the water film based on the water film thickness and the water film distribution state, so as to determine the degree of refraction influence of the environment on infrared rays as a whole, providing a reasonable basis for whether to perform erasure processing and determining the water film erasure frequency subsequently, thereby further helping to accelerate the response speed of the gas detector and improve the detection accuracy.

[0057] Please refer to Figure 2 shown, which is a step diagram for determining the refraction influence degree in an embodiment of the present invention; specifically, the absorption analysis unit determines the degree of influence of water vapor on the refractive index of infrared rays in the environment according to the environmental humidity, and determines the degree of influence of the water film on the refractive index of infrared rays on the surface of the infrared sensor according to the water film thickness and the water film distribution state, and, determines the refraction influence degree according to the degree of influence of water vapor, the degree of influence of the water film and the water film thickness.

[0058] Specifically, the degree of water vapor influence is the degree of influence of water vapor in the environment on infrared rays, which can be determined based on the environmental humidity. The degree of water film influence is the degree of influence of the water film on the surface of the infrared sensor in the environment on infrared rays, which can be determined based on the water film thickness and distribution state. The overall refractive influence of the environment on infrared rays is determined jointly based on the degree of water vapor influence and the degree of water film influence.

[0059] Specifically, the absorption analysis unit compares the environmental humidity with a preset humidity range to determine the deviation degree of the environmental humidity, and determines the degree of water vapor influence based on the deviation degree.

[0060] In practice, the humidity range in a normal environment is between 45%RH and 60%RH. Therefore, the value of the preset humidity range is 45%RH to 60%RH. Preferably, the value of the preset humidity range is 50%RH to 55%RH. If the environmental humidity is greater than the maximum value of the preset humidity range, it indicates that the water vapor in the environmental air is likely to affect infrared rays, and then the deviation degree is determined. The deviation degree is the difference between the environmental humidity and the maximum value of the preset humidity range. The deviation degree is positively correlated with the degree of water vapor influence. The greater the deviation degree, the greater the degree of water vapor influence. Generally, when the deviation degree changes by ±5%, the degree of water vapor influence increases by 0.1. When within the preset humidity range, the degree of water vapor influence is 0.

[0061] Please refer to Figure 3 as shown, which is a step diagram for determining the degree of water film influence in an embodiment of the present invention; specifically, the water film analysis unit includes a machine learning model, and the machine learning model is used to determine the water film distribution state according to the surface image;

[0062] Among them, the water film distribution state includes a uniform state, a non-uniform state, and a state without a water film (when the environmental humidity is less than the preset humidity threshold).

[0063] Specifically, the absorption analysis unit determines the degree of water film influence according to the water film distribution state, including,

[0064] If the water film distribution state is a uniform state, it is determined to calculate the propagation speed of infrared rays in the water film based on the water film thickness, and determine the degree of water film influence based on the propagation speed;

[0065] If the water film distribution state is a non-uniform state, it is determined to calculate the water-vapor ratio based on the water film distribution state, and determine the degree of water film influence by combining the water film refractive index and the air refractive index;

[0066] If the water film distribution state is a state without a water film, the degree of water film influence is 0.

[0067] Specifically, in the uniform state, the surface of the infrared sensor is completely covered by the water film area. When the thickness of the water film increases, it is equivalent to an increase in the optical path, and the propagation speed of light in the water film will slow down. The thickness of the water film is negatively correlated with the propagation speed. The change in the propagation speed will cause a change in the overall refractive index, thereby resulting in differences in the degree of influence of the water film. In the non-uniform state, the surface of the infrared sensor is covered by non-water film areas and water film areas. The water film distribution on the surface of the infrared sensor is uneven. The water-vapor ratio can reflect the relative content of water and air in the area of the infrared sensor surface. The size of the water-vapor ratio is mainly affected by the distribution state of the water film. The larger the water-vapor ratio, the larger the water film area, and the more infrared rays are absorbed by the water film. More infrared rays interact with water, which will interfere with the infrared absorption signal. The state without a water film indicates that there is no water film covering the surface of the infrared sensor, so the degree of influence of the water film does not need to be considered.

[0068] Specifically, the refractive index of the water film and the refractive index of air are the basic physical parameters of the propagation behavior of infrared rays in water and dry air. The water-vapor ratio is the relative ratio of water and air in the water film in the non-uniform state. The propagation path and propagation speed of infrared rays are affected by the water-vapor ratio, the refractive index of the water film, and the refractive index of air. Based on these three factors, the propagation situation of infrared rays in the non-uniform water film can be described quickly and comprehensively, and the influence of the water film on infrared detection can be evaluated more accurately.

[0069] In implementation, the water film analysis unit includes a pre-stored machine learning model to determine whether the water film distribution state is a uniform state, a non-uniform state, or a state without a water film based on the surface image. In the uniform state, the intensity of the outgoing light of infrared rays is different at different thicknesses. Therefore, according to the optical principle, the propagation speed of infrared rays in the water film can be determined. Compare the propagation speed with the propagation speed without a water film to determine the speed change rate. The speed change rate = |the propagation speed of infrared rays without interference - the propagation speed of infrared rays in the water film| ÷ the propagation speed of infrared rays without interference. The higher the speed change rate, the higher the degree of influence of the water film. The speed change rate is positively correlated with the degree of influence of the water film. For every 8% increase in the speed change rate, the degree of influence of the water film increases by 0.1. In the state without a water film, the degree of influence of the water film is 0.

[0070] In implementation, if the water film distribution state is non-uniform, the water film area and non-water film area determined by image processing of the collected surface image are used. The ratio of the area of the water film area to the non-water film area characterizes the water-vapor ratio. The larger the water-vapor ratio, the higher the concentration of water molecules in the water film, the stronger the absorption of infrared rays, and the greater the influence of the water film on the absorption of infrared rays. According to Snell's law, the refractive index of the water film, and the refractive index of air, the refraction angle of the infrared rays after entering the water film can be determined. The greater the change in the refraction angle, the greater the influence of the water film on the propagation direction of light. Therefore, the influence degree of the water film can be determined based on the water-vapor ratio and the refraction angle. For example, an influence degree model is constructed, and based on preset conditions, the relationship between the water film influence degree, the water-vapor ratio, and the refraction angle is trained and output to achieve quantitative analysis; the preset conditions are that when the change value of the refraction angle is within 5°, and the water-vapor ratio is below 1:10, the overall water film influence degree of the water film on infrared rays is small, and the value range of the water film influence degree is 0.1 to 0.15; if the change value of the refraction angle is 5° to 10°, and the water-vapor ratio is 1:10 to 3:10, then the value range of the water film influence degree is 0.2 to 0.4. In implementation, the water film influence degree is positively correlated with the change in the refraction angle and the water-vapor ratio respectively.

[0071] In the above embodiment, the absorption analysis unit of the present invention determines the water film contribution ratio and the water vapor contribution ratio of the infrared ray refractive index by the water film and water vapor respectively based on the comparison result of the water film thickness and the preset thickness to determine the refraction influence degree. While determining the influence of the overall environment on the refractive index, it provides a reasonable basis for whether to perform erasure processing and determine the water film erasure frequency subsequently, thereby further helping to accelerate the response speed of the gas detector and improve the detection accuracy.

[0072] Specifically, the absorption analysis unit determines the water film contribution ratio and the water vapor contribution ratio of the infrared ray refractive index by the water film and water vapor respectively based on the comparison result of the water film thickness, so as to weight the water film influence degree and the water vapor influence degree respectively, and determine the refraction influence degree according to the sum of the weighted water film influence degree and the weighted water vapor influence degree.

[0073] Specifically, the absorption analysis unit determines the relationship configuration of the water film contribution ratio and the water vapor contribution ratio based on the water film thickness, including,

[0074] If the water film thickness is less than or equal to the preset thickness, then the water vapor contribution ratio is constrained to be greater than the water film contribution ratio;

[0075] If the water film thickness is greater than the preset thickness, then the water film contribution ratio is constrained to be greater than the water vapor contribution ratio.

[0076] Specifically, when the environmental humidity is too high, water is dispersed in the air in a gaseous state, which will change the density of the air composition and thus affect the propagation of infrared rays in the air. The higher the environmental humidity, the higher the water vapor content, and the more obvious the absorption, scattering, etc. of infrared rays during the propagation process. Similarly, when the environmental humidity reaches a certain level, a water film will appear on the surface of the infrared sensor. When infrared rays pass through the water film and air interface, refraction and reflection phenomena will occur, and the thickness and distribution state of the water film will also significantly affect the degree of these optical phenomena.

[0077] Specifically, when the water film is relatively thin, the influence of the water film on infrared rays is relatively small. At this time, water vapor will have an impact on infrared rays within a larger spatial range, and the influence range is wider, so the contribution ratio of water vapor is greater than the contribution ratio of the water film. If the water film is thicker, the propagation path of infrared rays will change significantly when passing through the thick water film, and the refractive index will also change. Therefore, at this time, the contribution ratio of the water film is greater than the contribution ratio of water vapor.

[0078] In implementation, the value range of the preset thickness is 0.5 mm to 1 mm. Preferably, the value of the preset thickness is 0.8 mm. The sum of the contribution ratio of water vapor and the contribution ratio of the water film is 1. If the thickness of the water film is less than or equal to the preset thickness, the contribution ratio of water vapor is greater than the contribution ratio of the water film, then the contribution ratio of water vapor takes a value of 0.6 to 0.8. Preferably, the contribution ratio of water vapor takes a value of 0.65. The contribution ratio of the water film takes a value range of 0.2 to 0.4. Preferably, the contribution ratio of the water film takes a value of 0.35. If the thickness of the water film is greater than the preset thickness, then the contribution ratio of the water film is greater than the contribution ratio of water vapor, then the contribution ratio of the water film takes a value of 0.6 to 0.8. Preferably, the contribution ratio of the water film takes a value of 0.65. The contribution ratio of water vapor takes a value range of 0.2 to 0.4. Preferably, the contribution ratio of water vapor takes a value of 0.35. In implementation, the preset thickness and the values of the contribution ratio of the water film and the contribution ratio of water vapor can be adjusted according to the actual situation, as long as the sum of the contribution ratio of the water film and the contribution ratio of water vapor is 1, which will not be elaborated here.

[0079] In implementation, the degree of refraction influence = the degree of water film influence × the contribution ratio of the water film + the degree of water vapor influence × the contribution ratio of water vapor.

[0080] In the above embodiments, the absorption analysis unit of the present invention determines the contribution ratio of the water film and the contribution ratio of water vapor to the refractive index of infrared rays based on the comparison result of the water film thickness and the preset thickness to determine the degree of refraction influence. While determining the overall influence of the environment on the refractive index, it provides a reasonable basis for subsequent acceleration processing, thereby further helping to accelerate the response speed of the gas detector and improve the detection accuracy.

[0081] Specifically, the execution unit determines whether to perform an erasing process on the surface of the infrared sensor based on the degree of refraction influence, and determines the water film erasing frequency according to the determination result, including:

[0082] If the refraction influence degree is less than the preset influence degree, no erasing process is performed;

[0083] If the refraction influence degree is greater than or equal to the preset influence degree, erasing processing is performed, and the water film erasing frequency is determined according to the refraction influence degree and the preset influence degree.

[0084] Specifically, when there is a layer of water film on the sensor surface, due to the different refractive indices of water and air, infrared rays will be refracted when entering the water film from the air and then entering the sensor, causing the direction of light propagation to change, making the infrared signal received by the sensor deviate from the actual situation, thereby affecting the accuracy of detection. In order to obtain a more accurate gas concentration detection value, the system needs to further process the detection signal before outputting the gas detection value, which increases the response time of the gas detector.

[0085] In implementation, since both the water vapor in the environment and the water film on the surface of the infrared sensor will affect the degree of refraction, and when the environmental humidity exceeds the maximum value of the preset humidity range but is less than the preset humidity threshold, the water vapor content in the environment is high and the effect on the infrared is small. When the environmental humidity exceeds the preset humidity threshold, the water vapor content in the environment is high, and the water vapor will condense to form a water film, which has a greater impact on the infrared; therefore, the water film erasing frequency is determined according to the comparison result of the preset impact degree and the refraction impact degree. The value range of the preset impact degree is 0.1 to 0.4, and preferably, the value range of the preset impact degree is 0.3. If the refraction impact degree is less than the preset impact degree, the humidity in the environment will not affect the gas detector result, so no erasure processing is performed; if the refraction impact degree is greater than or equal to the preset impact degree, the erasure processing is performed, and the water film erasure frequency = preset erasure frequency × refraction impact degree ÷ preset impact degree, and the water film erasure frequency is rounded to the nearest integer. The value range of the preset erasure frequency is 1 time / min to 3 times / min, and preferably, the value of the preset erasure frequency is 2 times / min.

[0086] In implementation, the execution unit includes an erasing component, one end of which is located inside the gas detector and the other end is wrapped with an erasing material. Nanofiber cloth is used as the erasing material to absorb and erase water vapor and dust on the surface of the sensor.

[0087] In the above embodiment, the execution unit of the present invention determines the water film erasing frequency based on the degree of refraction influence, reduces the interference of water film and water vapor on infrared rays, promotes the gas to be detected to pass through the detection area faster, reduces the infrared refraction fluctuation caused by water film and water vapor, speeds up the response speed of the gas detector, and makes the detection signal more stable, thereby improving the accuracy of detection.

[0088] See also Figure 4As shown, it is a step diagram of the method of the embodiment of the present invention applied to the feedback system of a gas detection instrument. Specifically, the present invention also provides a method applied to the feedback system of a gas detection instrument with a fast response time, including:

[0089] Step S1, collect the ambient humidity in real time, and collect the surface image of the infrared sensor according to the ambient humidity;

[0090] Step S2, determine whether there is a water film distribution on the surface of the infrared sensor according to the surface image, and determine the water film thickness and the water film distribution state;

[0091] Step S3, determine the degree of refractive influence of the ambient humidity on the refractive index according to the ambient humidity, the water film thickness and the water film distribution state;

[0092] Step S4, determine whether to perform an erasing process on the surface of the infrared sensor based on the degree of refractive influence, and determine the water film erasing frequency according to the determination result.

[0093] Exemplarily, the application process of this embodiment in a certain factory building includes: installing and using an infrared gas detector in the factory building to detect the carbon dioxide concentration, and at the same time, equipping a high-precision humidity sensor for collecting the ambient humidity in real time, and a high-resolution industrial camera for collecting the surface image of the infrared sensor. The ambient humidity data and the surface image of the infrared sensor are collected every 0.2 s, and the data is transmitted to the data processing unit. After analysis by the water film analysis unit, it is found that there is an uneven water film on the surface, that is, the water film distribution state is non-uniform, the water film thickness is 2 mm. After calculation by the absorption analysis unit, it is determined that the degree of refractive influence of the ambient humidity on the refractive index under the corresponding ambient humidity, water film thickness and water film distribution state is 0.2, which is greater than the preset first influence degree of 0.2, so an erasing process is performed, and the water film erasing frequency is 2 times / min. After acceleration processing, the response time of the infrared gas detector is 2.3 s.

[0094] Exemplarily, the ambient humidity data and the surface image of the infrared sensor are collected every 0.2 s, and the data is transmitted to the data processing unit. After analysis by the water film analysis unit, it is found that there is a uniform water film on the surface, the water film thickness is 3.1 mm. After calculation by the absorption analysis unit, it is determined that the degree of refractive influence of the ambient humidity on the refractive index under the corresponding ambient humidity, water film thickness and water film distribution state is 0.53, which is greater than the preset influence degree of 0.2, so the water film on the surface of the infrared sensor is erased, and the water film erasing frequency is 5 times / min. After acceleration processing, the response time of the infrared gas detector is 3.1 s.

[0095] So far, the technical solution of the present invention has been described in conjunction with the preferred embodiments shown in the accompanying drawings. However, it is easily understood by those skilled in the art that the protection scope of the present invention is obviously not limited to these specific embodiments. Without departing from the principle of the present invention, those skilled in the art can make equivalent changes or substitutions to the relevant technical features, and the technical solutions after these changes or substitutions will fall within the protection scope of the present invention.

[0096] The above are only the preferred embodiments of the present invention and are not intended to limit the present invention. For those skilled in the art, the present invention can have various changes and modifications. Any modification, equivalent substitution, improvement, etc. made within the spirit and principle of the present invention shall be included in the protection scope of the present invention.

Claims

1. A gas detection instrument feedback system with fast response time, characterized in that: include: A monitoring unit, which is used to collect environmental humidity in real time and collect a surface image of the infrared sensor according to the environmental humidity; a water film analysis unit connected to the monitoring unit, for determining whether there is water film distribution on the surface of the infrared sensor according to the surface image, and determining the thickness of the water film and the distribution state of the water film; an absorption analysis unit connected to the monitoring unit and the water film analysis unit, for determining the degree of influence of the ambient humidity on the refractive index according to the ambient humidity, the thickness of the water film and the distribution state of the water film; The execution unit is connected to the absorption analysis unit, and determines whether to perform an erasing process on the surface of the infrared sensor based on the refraction influence degree, and determines the water film erasing frequency according to the determination result.

2. The gas detection instrument feedback system with fast response time according to claim 1, characterized in that: The water film analysis unit determines the water film area and the non-water film area on the surface of the infrared sensor according to the surface image, divides the water film area into a plurality of water film sub-areas, and determines the water film thickness and water film distribution state in each water film sub-area.

3. The gas detection instrument feedback system with fast response time according to claim 2 is characterized in that: The absorption analysis unit determines the degree of influence of water vapor in the environment on the infrared refractive index based on the ambient humidity, determines the degree of influence of water film on the infrared refractive index on the infrared sensor surface based on the water film thickness and the water film distribution state, and determines the refraction influence degree based on the water vapor influence degree, the water film influence degree and the water film thickness.

4. The gas detection instrument feedback system with fast response time according to claim 3 is characterized in that: The absorption analysis unit compares the ambient humidity with a preset humidity range to determine a deviation degree of the ambient humidity, and determines the water vapor influence degree based on the deviation degree.

5. The gas detection instrument feedback system with fast response time according to claim 1, characterized in that: The water film analysis unit includes a machine learning model, and the machine learning model is used to determine the distribution state of the water film according to the surface image; The water film distribution state includes a uniform state, a non-uniform state and a water film-free state.

6. The gas detection instrument feedback system with fast response time according to claim 5, characterized in that: The absorption analysis unit determines the influence degree of the water film according to the distribution state of the water film, including: If the water film distribution state is uniform, the propagation speed of infrared rays in the water film is determined based on the water film thickness, and the influence of the water film is determined based on the propagation speed; If the water film distribution state is non-uniform, the water-gas ratio is determined based on the water film distribution state, and the influence of the water film is determined by combining the refractive index of the water film and the refractive index of the air; If the water film distribution state is a water film-free state, the water film influence degree is 0.

7. The gas detection instrument feedback system with fast response time according to claim 6, characterized in that: The absorption analysis unit determines the water film contribution ratio and water vapor contribution ratio of the water film and water vapor to the infrared refractive index based on the comparison result between the water film thickness and the preset thickness, so as to weight the water film influence degree and the water vapor influence degree respectively, and determines the refraction influence degree according to the sum of the weighted water film influence degree and the weighted water vapor influence degree.

8. The gas detection instrument feedback system with fast response time according to claim 7, characterized in that: The absorption analysis unit determines the relationship between the water film contribution ratio and the water vapor contribution ratio based on the water film thickness, including: If the water film thickness is less than or equal to the preset thickness, the water vapor contribution ratio is constrained to be greater than the water film contribution ratio; If the water film thickness is greater than the preset thickness, the water film contribution ratio is constrained to be greater than the water vapor contribution ratio.

9. The gas detection instrument feedback system with fast response time according to claim 1, characterized in that: The execution unit determines whether to perform an erasing process on the surface of the infrared sensor based on the refraction influence degree, and determines a water film erasing frequency according to the determination result, including: If the refraction influence degree is less than the preset influence degree, no erasing process is performed; If the refraction influence degree is greater than or equal to the preset influence degree, erasing processing is performed, and the water film erasing frequency is determined according to the refraction influence degree and the preset influence degree.

10. A method for applying the feedback system of a gas detection instrument with fast response time as claimed in any one of claims 1 to 9, characterized in that: include: Collecting environmental humidity in real time, and collecting a surface image of an infrared sensor according to the environmental humidity; Determine whether there is water film distributed on the surface of the infrared sensor according to the surface image, and determine the thickness and distribution state of the water film; Determining the degree of influence of the ambient humidity on the refractive index according to the ambient humidity, the water film thickness and the water film distribution state; Whether to perform erasing processing on the surface of the infrared sensor is determined based on the refraction influence degree, and the water film erasing frequency is determined according to the determination result.

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