Gas sensor capable of switching the type of gas being measured and gas concentration detection method

Abstract

The present invention discloses a gas sensor capable of switching the type of gas to be measured and a method for detecting gas concentration, and relates to the field of new material technology. The sensor includes a gas type determination module, a gas chamber, a light source, an optical signal detection module, a broadband filter element, and a control processing module; the gas type determination module receives gas type information input by a user and transmits it to the control processing module; the gas chamber contains the gas to be measured, the light source is on the light input side, and the optical signal detection module is on the light output side; the broadband filter element filters out the target infrared light signal emitted by the light source, allowing it to pass through the gas to be measured and project toward the optical signal detection module; the optical signal detection module converts the optical signal into a digital signal and transmits it to the control processing module, which determines the gas concentration based on the gas type determination information and a preset model. The present invention achieves effective and accurate detection of different gas concentrations and improves the detection efficiency of multiple gas concentrations.

Description

Technical Field

[0001] The present invention relates to the field of new material technology, and in particular to a gas sensor capable of switching the type of gas being measured and a gas concentration detection method. Background Art

[0002] Relevant standardization in the field of new materials refers to the formulation and compliance of a series of unified technical specifications and quality requirements in the research and development, production, testing, application and supervision of new materials. These standards cover the chemical composition, physical properties, production methods, safe use, environmental impact, and evaluation and testing methods of the materials. They aim to ensure the consistency, reliability and safety of new materials, promote technological innovation, reduce production costs, improve market competitiveness, and protect public health and environmental safety.

[0003] In the production and manufacturing process of new materials, gas concentration detection is required in many aspects of relevant standardization. Gas concentration detection not only ensures product quality and the safety of the production process, but also has an important impact on environmental control, process optimization, energy efficiency improvement and cost-effectiveness.

[0004] Currently, in the production and manufacturing of new materials, NDIR (Non-Dispersive InfraRed) gas sensors are widely used for gas detection. NDIR gas sensors use narrow-band filtering to filter out infrared light of a specific wavelength and use the selective absorption characteristics of specific gas molecules on infrared light of a specific wavelength to detect the concentration of gases with specific fingerprint absorption bands.

[0005] In related technologies, when using NDIR gas sensors to detect multiple gases, they must be specifically manufactured for each gas to match the optical platform, narrowband filter elements, characteristic curve, and gas concentration. This means that each gas sensor model can only detect a single type of gas. When detecting multiple gases, multiple sensor models are required, and the gas sensors must be replaced multiple times during the detection process, making the detection process cumbersome and reducing detection efficiency. Summary of the Invention

[0006] In response to the above-mentioned technical problems and defects, the purpose of the present invention is to provide a gas sensor and gas concentration detection method that can switch the type of gas to be measured. The information can be determined based on the gas type input by the user, and the target infrared light signal can be filtered out by a broadband filter element. After conversion by the optical signal detection module, the control processing module determines the concentration of the gas to be measured based on a preset model, thereby realizing effective and accurate detection of different gas concentrations and improving the detection efficiency of multiple gas concentrations.

[0007] To achieve the above-mentioned purpose, the present invention provides a gas sensor capable of switching the type of gas to be measured, comprising a gas type determination module, a gas chamber, a light source, an optical signal detection module, a broadband filter element and a control processing module; the gas type determination module is used to receive gas type determination information of the gas to be measured input by a user, and transmit the gas type determination information to the control processing module; the gas chamber is used to accommodate the gas to be measured, the light source is arranged on the light incident side of the gas chamber, and the optical signal detection module is arranged on the light exit side of the gas chamber; the broadband filter element is arranged at the signal transmitting end of the light source, and is used to filter out the detection light signal emitted by the light source, which has a set wavelength range. The target infrared light signal within the range is received, so that the target infrared light signal passes through the gas to be measured and is emitted to the optical signal detection module; the optical signal detection module is used to convert the received target infrared light signal into an optical signal intensity digital signal, and transmit the optical signal intensity digital signal to the control processing module; the control processing module is used to determine information according to the gas type, determine the target gas characteristic model corresponding to the gas to be measured from a preset gas characteristic model library, and determine the detection concentration of the gas to be measured according to the optical signal intensity digital signal and the target gas characteristic model, and the target gas characteristic model is used to characterize the corresponding relationship between optical signal intensity and gas concentration.

[0008] In the present invention, the gas type determination module can receive the information on the type of gas to be detected input by the user. This design allows the user to flexibly select the type of gas to be detected according to actual needs, and is no longer limited to single gas detection. Secondly, the broadband filter element filters out the target infrared light signal within the set wavelength range. This element does not respond to specific gases and can adapt to a variety of gas detection needs. There is no need to equip each gas with a specific filter element like a narrow-band filter element, which reduces the tedious operations caused by replacing sensors. Furthermore, the control processing module determines the corresponding target gas characteristic model from the preset gas characteristic model library based on the gas type determination information, and uses the model and the optical signal intensity digital signal transmitted by the optical signal detection module to determine the concentration of the gas to be measured. The same sensor can detect different gases through model switching without replacing the sensor, which greatly improves the detection efficiency and optimizes the entire gas detection process. It has significant advantages in the production and manufacturing of new materials.

[0009] In combination with some embodiments of the first aspect, in some embodiments, the gas sensor also includes an environmental detection module, which is arranged in the gas chamber and is used to detect environmental information in the gas chamber and send the environmental information to the control processing module. The control processing module is also used to compensate the detection concentration according to the environmental information to obtain the environmental compensated concentration of the gas being measured.

[0010] The technical solutions of the above embodiments can detect environmental information within a gas chamber. Environmental factors such as temperature, humidity, and air pressure can affect gas concentration detection. By sending this environmental information to the control processing module through the environmental detection module, the detected concentration can be compensated to obtain a more accurate environmentally compensated concentration of the measured gas. This avoids detection errors caused by interference from environmental factors, enabling the gas sensor to provide reliable gas concentration detection results under different environmental conditions, thereby improving detection accuracy and practicality.

[0011] In combination with some embodiments of the first aspect, in some embodiments, the control processing module is specifically used to input the environmental information into a preset environmental compensation model to obtain an environmental compensation factor, and determine the environmental compensation concentration based on the environmental compensation factor and the detected concentration.

[0012] Using the technical solution of the above embodiment, the control processing module inputs environmental information into a preset environmental compensation model to obtain an environmental compensation factor, which is then used to determine the environmental compensation concentration. This method has the advantage of taking into account the effects of ambient temperature, humidity, and air pressure on the detection results through a precise mathematical model. Using the environmental compensation factor to correct the detected concentration allows the gas sensor to accurately reflect the true concentration of the measured gas in a variety of complex environments, ensuring the accuracy and stability of the measurement results and improving the reliability and adaptability of the sensor.

[0013] In conjunction with some embodiments of the first aspect, in some embodiments, the environmental information includes ambient temperature, ambient humidity, and ambient air pressure, and the environmental compensation model includes:

[0014] C corrected =C×F(T,H,P);

[0015]

[0016] Wherein, C is the detection concentration, C corrected is the environmental compensation concentration, F(T,H,P) is the environmental compensation factor, T is the ambient temperature, H is the ambient humidity, P is the ambient pressure, T0 is the reference temperature, H0 is the reference humidity, P0 is the reference pressure, α, β, γ are experimental parameters, and e is a natural constant.

[0017] Using the technical solutions of the above-mentioned embodiments, the environmental compensation model takes into account factors such as ambient temperature, humidity, and air pressure, and calculates the environmental compensation concentration using a specific formula. Its advantage lies in the ability to scientifically quantify the impact of environmental factors on gas concentration detection by introducing experimental parameters and natural constants. This calculation method, based on a precise formula, can more accurately compensate for the detected concentration, enabling the sensor to adapt to measurement requirements under different environmental conditions. Whether in high temperature, high humidity, or varying air pressure environments, it can effectively improve the accuracy of measurement results and ensure the detection reliability of gas sensors in various environments.

[0018] In combination with some embodiments of the first aspect, in some embodiments, the broadband filter element includes a silicon-based broadband pass filter, and the transmittance of the silicon-based broadband pass filter to the target infrared light signal is above 80%.

[0019] Using the technical solution of the above embodiment, the broadband filter element includes a silicon-based broadband pass filter with a transmittance of over 80% for the target infrared light signal. This feature allows the target infrared light signal to pass through the filter efficiently, reducing light signal loss during the filtering process and ensuring that a sufficient intensity of light signal passes through the measured gas to reach the optical signal detection module. This helps improve the accuracy of the signal received by the optical signal detection module, thereby enhancing the accuracy of gas concentration detection, ensuring the reliability and stability of the sensor during the detection process, and enabling more accurate data when detecting gas concentration.

[0020] In combination with some embodiments of the first aspect, in some embodiments, the wavelength of the target infrared light signal is 8 um to 14 um.

[0021] In the technical solution of the above embodiment, the wavelength of the target infrared light signal is 8 to 14 μm, a wavelength range that is of great significance. Many gases have unique absorption characteristics within this wavelength range. By setting the target infrared light signal within this range, the gas's absorption characteristics of infrared light can be better utilized for concentration detection. This enables more accurate identification and measurement of the concentration of the measured gas, reduces interference from other wavelengths, improves detection specificity and sensitivity, ensures that the gas sensor can obtain accurate data when detecting the target gas, and enhances the effectiveness and accuracy of the detection method.

[0022] In combination with some embodiments of the first aspect, in some embodiments, the broadband filtering element includes an adaptive filtering module, which is used to adjust the transmittance according to the information determined by the gas type, and the adaptive filtering module includes liquid crystal or electrochromic material.

[0023] Adopting the technical solution of the above embodiment, an adaptive filter module can adjust transmittance based on information determined by gas type, employing liquid crystal or electrochromic materials. The advantage of this design is that the filter element's transmittance can be flexibly adjusted according to the type of gas being measured. Given the absorption characteristics of different gases at different wavelengths, the adaptive filter module can optimize the target infrared light signal, ensuring optimal interaction between the light signal and the measured gas, thereby improving the accuracy of gas concentration detection and increasing the adaptability and versatility of the gas sensor for detecting different gases.

[0024] In combination with some embodiments of the first aspect, in some embodiments, the gas type determination module further includes a voice recognition module, which is used to receive a voice signal sent by the user and recognize the voice signal to obtain the gas type determination information.

[0025] Using the technical solutions of the above embodiments, the voice recognition module can receive user voice signals and identify the gas type. This design facilitates user operation, especially when the user's hands are not handy or when the detection gas type needs to be quickly switched. Voice input allows for easy setup. This improves operational convenience and efficiency, avoids operational errors caused by tedious manual input, and makes the gas sensor more user-friendly in actual use, meeting user needs in different scenarios and enhancing the user experience.

[0026] In combination with some embodiments of the first aspect, in some embodiments, the gas sensor further includes a display module connected to the control processing module, for displaying the detected concentration of the measured gas.

[0027] By adopting the technical solutions of the above embodiments, the display module can intuitively present the test results to the user. Whether in scenarios such as industrial production environment monitoring, laboratory research, or ambient air quality testing, users can directly see the concentration of the measured gas at a glance on the display module without having to use other complex equipment or operations to obtain data. This allows users to quickly judge environmental conditions and make appropriate decisions, improving the readability and usability of test results and facilitating rapid assessment of test results.

[0028] In a second aspect, the present invention provides a gas concentration detection method, which uses the gas sensor provided in the first aspect. The method includes: placing the gas sensor in a target area; setting the gas type of the gas to be measured on the gas sensor; and obtaining the detection concentration of the gas to be measured from the gas sensor after a set time.

[0029] The present invention places a gas sensor in a target area, sets the type of gas to be measured, and acquires the measured concentration after a set time. This simplifies the gas concentration detection process and allows for efficient and effective gas concentration detection. A rational operating process ensures that the sensor accurately collects and analyzes gas samples in the target area, obtaining reliable test results within the specified timeframe. This makes it suitable for a variety of applications requiring gas concentration detection, from gas monitoring in industrial production processes to air quality monitoring in environmental monitoring, effectively providing accurate gas concentration data.

[0030] One or more technical solutions provided by the present invention have at least the following technical effects or advantages:

[0031] 1. The gas sensor of the present invention can detect different gases based on the gas type determination information input by the user. Its gas type determination module can receive user input in various forms (such as voice recognition), which is convenient for user operation. In addition, the control processing module can determine the corresponding target gas characteristic model based on the preset gas characteristic model library, and accurately determine the detection concentration of the measured gas in combination with the optical signal intensity digital signal converted by the optical signal detection module. This means that in a variety of gas detection scenarios, the sensor can quickly switch the detection object and ensure the accuracy of the detection results. It can play an important role in both the monitoring of different process gases in industrial production processes and the detection of various types of harmful gases in environmental monitoring.

[0032] 2. By setting up an environmental detection module, the present invention enables the gas sensor to take into account the influence of factors such as ambient temperature, humidity and air pressure on gas concentration detection. The control processing module uses a preset environmental compensation model to compensate the detected concentration to obtain a more accurate environmental compensation concentration. In practical applications, environmental conditions are often changeable. For example, when monitoring outdoor environments, changes in weather can lead to changes in temperature, humidity and air pressure. The sensor can provide reliable detection results in different environments, avoiding measurement errors caused by interference from environmental factors, enabling it to be widely used in gas concentration detection in various complex environments, and ensuring the stability and reliability of measurement data.

[0033] 3. Broadband filter elements play an important role in this technical solution. On the one hand, the silicon-based broadband filter has a high transmittance (more than 80%) for the target infrared light signal of 8-14μm, ensuring that the light signal of sufficient intensity can pass through the measured gas to reach the light signal detection module, reducing the loss of light signal and improving the detection accuracy. On the other hand, the adaptive filter module uses liquid crystal or electrochromic materials, which can flexibly adjust the transmittance according to the information determined by the gas type, and optimize the interaction between the target infrared light signal and the measured gas. This enables the sensor to better utilize the absorption characteristics of the gas for infrared light detection, enhances the specificity and sensitivity of the detection of different gases, and improves the detection performance of the entire gas sensor. BRIEF DESCRIPTION OF THE DRAWINGS

[0034] The accompanying drawings are incorporated into and constitute a part of the specification, illustrate embodiments consistent with the present invention, and together with the specification, are used to explain the principles of the present invention. Obviously, the drawings described below are only some embodiments of the present invention, and those skilled in the art can derive other drawings based on these drawings without inventive effort. In the drawings:

[0035] Figure 1 1 is a schematic diagram of the structure of a gas sensor capable of switching the type of gas being measured according to an embodiment of the present invention;

[0036] Figure 2 This is a schematic diagram of the functional modules of a gas sensor capable of switching the type of gas being measured according to an embodiment of the present invention;

[0037] Figure 3 Schematic diagram of the transmittance variation of a narrow bandpass filter in the related art;

[0038] Figure 4 Schematic diagram of the transmittance change of the silicon-based wide-bandpass filter in an embodiment of the present invention. DETAILED DESCRIPTION

[0039] The terms used in the following embodiments of the present invention are for the purpose of describing specific embodiments only and are not intended to limit the present invention. As used in the specification of the present invention, the singular expressions "a," "an," "above," "the," and "this" are intended to include the plural expressions as well, unless the context clearly indicates otherwise. It should also be understood that the term "and / or" as used in the present invention refers to any and all possible combinations of one or more of the listed items.

[0040] Hereinafter, the terms "first" and "second" are used for descriptive purposes only and should not be construed as implying relative importance or implicitly indicating the quantity of the technical features indicated. Thus, a feature designated "first" or "second" may explicitly or implicitly include one or more of such features. In the description of the embodiments of the present invention, unless otherwise specified, "plurality" means two or more.

[0041] It should also be noted that, unless otherwise clearly specified and limited, in the embodiments of the present invention, terms such as "setting" and "connection" should be understood in a broad sense. For example, "connection" can be a fixed connection, a detachable connection, or an integral connection; it can be a mechanical connection or an electrical connection; it can be a direct connection or an indirect connection through an intermediate medium, or it can be the internal connection of two components; it can be a wired communication connection or a wireless communication connection. For those of ordinary skill in the art, the specific meanings of the above terms in the present invention can be understood according to the specific circumstances. The embodiments of the present invention are described in detail below.

[0042] The embodiment of the present invention provides a gas sensor capable of switching the type of gas being measured, such as Figure 1 and Figure 2 As shown, the gas sensor includes a gas type determination module 1, a gas chamber 2, a light source 3, an optical signal detection module 4, a broadband filter element 5 and a control processing module 6.

[0043] In which: the gas type determination module 1 is used to receive gas type determination information of the measured gas input by the user and transmit the gas type determination information to the control processing module 6; the gas chamber 2 is used to accommodate the measured gas, the light source 3 is arranged on the light input side of the gas chamber 2, and the optical signal detection module 4 is arranged on the light output side of the gas chamber 2; the broadband filter element 5 is arranged at the signal transmission end of the light source 3, and is used to filter out the target infrared light signal within a set wavelength range in the detection light signal emitted by the light source 3, so that the target infrared light signal passes through the measured gas and is emitted to the optical signal detection module 4; the optical signal detection module 4 is used to convert the received target infrared light signal into a digital signal of optical signal intensity and transmit the digital signal of optical signal intensity to the control processing module 6; the control processing module 6 is used to determine the target gas characteristic model corresponding to the measured gas from a preset gas characteristic model library based on the gas type determination information, and determine the detection concentration of the measured gas based on the digital signal of optical signal intensity and the target gas characteristic model. The target gas characteristic model is used to characterize the corresponding relationship between optical signal intensity and gas concentration.

[0044] First, the present embodiment utilizes a gas type determination module 1, allowing the user to select the gas type to be measured as needed. This flexibility improves detection efficiency and avoids the cumbersome process of multiple sensor replacements required in traditional methods. Second, the introduction of a broadband filter element 5 replaces the traditional narrowband filter element, enabling the gas sensor to adapt to different gas detection requirements through software configuration rather than hardware modifications. This not only reduces production costs but also simplifies the production process.

[0045] Furthermore, the configuration of the gas chamber 2, light source 3, and optical signal detection module 4 ensures effective interaction between the measured gas and infrared light. The control processing module 6, based on the user-entered gas type information, calls the corresponding target gas characteristic model from the built-in gas characteristic model library to accurately calculate the correspondence between optical signal intensity and gas concentration. This design not only enhances the sensor's automation and intelligence level but also increases the system's flexibility and scalability by reducing hardware dependence.

[0046] Through this integrated and modular design, the gas sensor of this embodiment can rapidly respond to the detection requirements of varying gas concentrations during the new material production process while ensuring detection accuracy and reliability. This not only optimizes the production process and reduces operational complexity, but also facilitates stricter quality control and environmental monitoring, thereby ensuring the safety and efficiency of new material production while also meeting industry standardization requirements.

[0047] In this embodiment, the specific working process of the gas sensor is as follows:

[0048] (1) Gas type determination stage:

[0049] The user first interacts with the gas type determination module 1 and enters information identifying the type of gas being measured. This information can be entered in a variety of ways, such as by selecting the corresponding gas type option on the device connected to the sensor or by entering a specific command code. Upon receiving this information, the gas type determination module 1 immediately and accurately transmits it to the control and processing module 6 in the form of a digital signal. Upon receiving this signal, the control and processing module 6 marks the gas type being detected in its internal program, preparing for the subsequent selection of an appropriate characteristic model.

[0050] (2) Light source 3 emission and optical signal filtering stage:

[0051] The control processing module 6 controls the light source 3 to enter the working state, and the light source 3 begins to emit light containing multiple wavelength components (detection light signal). These light rays propagate into the gas chamber 2, and before reaching the gas chamber 2, the light rays first pass through the broadband filter element 5. The unique optical properties of the broadband filter element 5 enable it to screen out target infrared light signals within a set wavelength range. This wavelength range is carefully designed to cover the wavelength region with absorption characteristics of multiple gas molecules. Unlike traditional narrow-band filter elements, the broadband filter element 5 does not need to be replaced for each gas, but can provide a wider wavelength range, which is suitable for multiple gas detection. For example, it can allow infrared light in a specific wavelength range, such as 8.0-14.0μm wavelength range, to pass through. This range can cover the absorption bands of many common gas molecules, thereby laying the foundation for the subsequent detection of multiple gases.

[0052] (3) Gas absorption and optical signal detection stage:

[0053] The target infrared light signal, after being filtered by the broadband filter element 5, enters the gas chamber 2 and interacts with the gas to be measured contained therein. The molecules in the gas to be measured will selectively absorb infrared light of a specific wavelength, which is based on the internal structure of the gas molecules and the principle of energy level transition. Different types of gas molecules have different vibrational and rotational energy levels. They will undergo energy level transitions under the action of infrared light of a specific wavelength, thereby absorbing light energy of the corresponding wavelength. When the target infrared light signal passes through the gas to be measured in the gas chamber 2, the intensity of the light signal will change accordingly according to the gas concentration and the absorption characteristics of the gas molecules to light. After passing through the gas, the light signal reaches the light signal detection module 4. The light signal detection module 4 uses principles such as the photoelectric effect to convert the received light signal intensity into an electrical signal, and then converts the electrical signal into a light signal intensity digital signal through a built-in analog-to-digital converter, and finally transmits the digital signal to the control processing module 6.

[0054] (IV) Concentration calculation and output stage:

[0055] After receiving the digital signal of optical signal intensity, the control processing module 6 retrieves the corresponding target gas characteristic model from a preset gas characteristic model library based on the previously marked gas type information. These characteristic models were established during the sensor development phase through extensive experiments and data analysis. They accurately describe the quantitative relationship between optical signal intensity and gas concentration for different gas types. The control processing module 6 substitutes the received digital signal of optical signal intensity into the target gas characteristic model and performs calculations using a pre-set mathematical algorithm. For example, algorithms such as linear regression and nonlinear fitting may be used to calculate the precise concentration of the measured gas based on the parameters in the model and the input optical signal intensity data.

[0056] The gas characteristic model can also include a gas characteristic curve. The gas characteristic curve is obtained through a large number of experiments and precise measurements. It presents the complex and precise correspondence between different light signal intensities and gas concentrations in the form of intuitive graphics or mathematical expressions. When the target infrared light signal within a specific wavelength range passes through the gas being measured, the gas molecules will absorb part of the light energy according to their own characteristics, resulting in a change in the light signal intensity. This change is closely related to the gas concentration. The higher the gas concentration, the stronger the absorption of the light signal and the more obvious the attenuation of the light signal intensity. The gas characteristic curve records in detail the law of change of the light signal intensity with the gas concentration, and it provides a standard reference system for the control processing module 6. The control processing module 6 finds the corresponding position in the corresponding gas characteristic curve based on the received light signal intensity digital signal, and then determines the accurate concentration of the gas being measured, thereby achieving accurate detection of the gas concentration. This mechanism is the key to the gas sensor's ability to accurately measure different gas concentrations.

[0057] Finally, the control processing module 6 outputs the calculated gas concentration result in an appropriate manner, such as displaying it on a display screen, transmitting it to other devices through a communication interface, etc., so that the user can obtain the detection result and complete the entire gas detection process.

[0058] Through the above workflow, the gas sensor of this embodiment can efficiently and accurately detect the concentrations of multiple different types of gases, overcoming the disadvantage of traditional sensors that require frequent replacement of sensors when detecting multiple gases, and providing a reliable and convenient solution for gas detection in fields such as new material production and manufacturing.

[0059] In some embodiments, the gas sensor also includes an environmental detection module 7, which is arranged in the gas chamber 2 and is used to detect the environmental information in the gas chamber 2 and send the environmental information to the control processing module 6. The control processing module 6 is also used to compensate the detection concentration according to the environmental information to obtain the environmental compensated concentration of the gas being measured.

[0060] This embodiment greatly improves the accuracy and reliability of detection through the above-mentioned environmental detection module 7. The environmental detection module 7 is placed in the gas chamber 2, and includes a temperature detection module, a humidity detection module and an air pressure detection module, which can monitor the environmental information in the gas chamber 2 in real time, such as key parameters such as temperature, humidity, and air pressure. During the detection process, environmental factors may have a significant impact on the gas concentration measurement results. For example, temperature changes will change the movement speed and energy level distribution of gas molecules, thereby affecting the gas's absorption characteristics of light signals. When the environmental detection module 7 obtains the environmental information, it will quickly send it to the control processing module 6. The control processing module 6 relies on pre-built-in algorithms and compensation models to comprehensively consider the impact of environmental information on gas concentration measurement, and accurately compensates the detection concentration calculated based on the light signal intensity digital signal and the target gas characteristic model.

[0061] By correcting the measurement deviation caused by environmental factors, a more accurate environmental compensation concentration of the measured gas can be obtained, thereby ensuring high-precision gas concentration detection under different environmental conditions and providing more reliable data support for practical applications.

[0062] In some embodiments, the control processing module 6 is specifically configured to input the environmental information into a preset environmental compensation model to obtain an environmental compensation factor, and determine the environmental compensation concentration based on the environmental compensation factor and the detected concentration.

[0063] Specifically, when the environmental detection module 7 transmits the environmental information within the gas chamber 2 to the control processing module 6, the control processing module 6 quickly activates a preset environmental compensation model. This environmental compensation model is constructed based on a large amount of experimental data and theoretical research. It can accurately analyze the complex relationship between environmental information (such as temperature, humidity, and air pressure) and gas concentration measurements.

[0064] The control processing module 6 inputs the received real-time environmental information into the environmental compensation model. After a series of complex calculations and logical decisions, the model outputs a corresponding environmental compensation factor. This environmental compensation factor is a quantitative value that intuitively reflects the degree to which the current environmental conditions affect the gas concentration measurement. The control processing module 6 then uses this environmental compensation factor in conjunction with the detected concentration previously calculated by the optical signal detection module 4 and the gas characteristic model.

[0065] Specifically, the control processing module 6 will adjust the detection concentration accordingly according to the environmental compensation factor. For example, when the environmental compensation factor is greater than 1, it may mean that the current environment has a positive impact on the measurement and the detection concentration needs to be appropriately increased; otherwise, the detection concentration needs to be reduced.

[0066] Through this precise calculation method, the control processing module 6 ultimately determines the environmentally compensated concentration of the measured gas after environmental compensation, thereby effectively eliminating the interference of environmental factors on the gas concentration detection results, greatly improving the accuracy and reliability of the measurement, and providing a solid technical guarantee for the application of gas sensors in various complex environments.

[0067] In some embodiments, the environmental information includes environmental temperature, environmental humidity, and environmental pressure, and the environmental compensation model includes:

[0068] C corrected =C×F(T,H,P);

[0069]

[0070] Wherein, C is the detection concentration, C corrected is the environmental compensation concentration, F(T,H,P) is the environmental compensation factor, T is the ambient temperature, H is the ambient humidity, P is the ambient pressure, T0 is the reference temperature, H0 is the reference humidity, P0 is the reference pressure, α, β, γ are experimental parameters, and e is a natural constant.

[0071] Specifically, the determination of the reference temperature T0, reference humidity H0, and reference air pressure P0 is usually based on experimental or equipment calibration conditions. These reference values are usually the environmental parameters when the equipment is calibrated under laboratory conditions, or the most common or standard environmental conditions in a specific application scenario. For example, T0 may be the indoor temperature when the equipment is calibrated, such as 298K; H0 may be the relative humidity during calibration, such as 50%; P0 may be the standard atmospheric pressure, such as 101.325kPa. These values can be determined by consulting the technical manual, calibration report, or communicating with the manufacturer. In the absence of specific calibration conditions, the standard environmental conditions recommended by the International Organization for Standardization (ISO) or relevant industry standards can be used as a reference.

[0072] The parameters α, β, and γ are obtained by fitting experimental data, which means that the model can be customized and optimized according to the specific sensor characteristics and application environment.

[0073] in, is the temperature compensation factor. Temperature has a direct impact on the mobility of gas molecules, thus affecting the detected gas concentration. As temperature increases, molecular motion accelerates, the number of molecules per unit volume decreases, and the detected concentration decreases. The reverse is also true. By raising the ratio of the actual temperature T to the reference temperature T0 to a power, the effect of temperature changes on gas concentration can be simulated. Parameter α is an experimentally determined coefficient used to adjust the sensitivity to temperature effects.

[0074] and is the humidity compensation factor. Changes in humidity affect the interaction between gas molecules and water molecules, thereby affecting the detected concentration of the gas. Increased humidity may cause competition between gas molecules and water molecules, affecting the response of the sensor. The natural logarithmic function ln(1+H / H0) is used to describe the effect of humidity because the logarithmic function can handle nonlinear changes in humidity, and when the humidity is low, the change of the logarithmic function is relatively gentle, while when the humidity is high, the change is more significant. The parameter β is an experimentally determined coefficient used to adjust the sensitivity of the humidity effect. Finally, 1 is added to the result of the logarithmic function to ensure that the compensation factor will not be less than 1 even when the humidity is 0. This ensures that the compensated concentration value will not be lower than the original detection concentration.

[0075] at the same time, The pressure compensation factor is the air pressure compensation factor. Changes in air pressure affect the density of gas molecules, thereby affecting the detected gas concentration. As air pressure increases, the number of molecules per unit volume increases, resulting in an increase in the detected concentration. And vice versa. The exponential function is used to describe the effect of air pressure because it can well simulate the nonlinear effect of air pressure changes on gas concentration. The parameter γ is an experimentally determined coefficient used to adjust the sensitivity of the air pressure effect.

[0076] This model considers the effects of temperature, humidity, and air pressure, combining them into a single environmental compensation factor F(T,H,P) using a multiplicative approach. This multiplicative approach is based on the assumption that the effects of temperature, humidity, and air pressure are independent of each other.

[0077] This environmental compensation model rationally considers the effects of temperature, humidity, and air pressure on gas detection concentration. By introducing experimental parameters, the model has better adaptability and accuracy. This model can provide more accurate environmental compensation for gas sensors, thereby improving the reliability of detection results.

[0078] In some embodiments, the broadband filter element 5 comprises a silicon-based broadband pass filter, the transmittance of the silicon-based broadband pass filter to the target infrared light signal is above 80%, wherein the wavelength of the target infrared light signal is 8 μm to 14 μm.

[0079] Specifically, the silicon-based wide-bandpass filter is carefully designed to filter out the target infrared light signal, and it has an extremely high transmittance for the target infrared light signal, reaching more than 80%. This means that in the light emitted by the light source 3 containing multiple wavelength components, when the light passes through the silicon-based wide-bandpass filter, more than 80% of the target infrared light signal can be smoothly transmitted, while other unnecessary wavelength components are effectively filtered out. This high transmittance characteristic ensures that the target infrared light signal with sufficient intensity can enter the gas chamber 2 and interact with the measured gas, thereby providing a sufficient light signal intensity basis for the subsequent accurate detection of gas concentration. At the same time, the silicon-based material itself has good stability and optical properties, and can adapt to a variety of complex working environments, ensuring the reliability of the performance of the broadband filter element 5 during long-term use, helping to maintain the stability and accuracy of the overall detection performance of the gas sensor, and providing a strong guarantee for accurate measurement of gas concentration in different scenarios.

[0080] Figure 3 This figure shows the transmittance variation of a related art NBP (narrow bandpass filter) at a reference wavelength of 3.90 μm / 90 nm. The horizontal axis represents wavelength (in μm), ranging from 3.0 to 4.4 μm, and the vertical axis represents transmittance (in %), ranging from 0 to 100%. Figure 3 The middle curve represents the transmittance change within this wavelength range. The curve has an obvious peak near 3.90μm. The narrowband filter has good transmittance performance only in the wavelength range of 3.0 to 4.4μm, and its wavelength range is relatively narrow.

[0081] In this embodiment, reference Figure 4 , showing the transmittance variation of SiWBP (silicon-based wide-bandpass filter) in the wavelength range of 8.0-14.0μm. Figure 4 The horizontal axis represents wavelength (in μm) ranging from 0 to 18 μm, and the vertical axis represents transmittance (in %) ranging from 0 to 100%. Figure 4 The middle curve represents the change in transmittance within this wavelength range. The curve has obvious fluctuations between 8μm and 14μm, showing the change in transmittance when light within this band passes through the material.

[0082] The silicon-based wide-bandpass filter exhibits excellent performance for target infrared light signals with a wavelength of 8μm to 14μm, and its transmittance for the target infrared light signal is as high as over 80%. During operation, the light emitted by the light source 3 contains components of many different wavelengths. When these lights reach the silicon-based wide-bandpass filter, it acts like a precise filter. With its special optical structure and material properties, it preferentially allows target infrared light signals in the wavelength range of 8μm to 14μm to pass through at a higher ratio (over 80%), while filtering out most of the light of other wavelengths. This high transmittance characteristic ensures that a sufficiently strong and pure target infrared light signal can smoothly enter the gas chamber 2 and fully interact with the measured gas therein.

[0083] Since the wavelength range of 8μm to 14μm is exactly in the band where many gas molecules have significant absorption characteristics, the high transmittance ensures that there are sufficient light signals for subsequent detection processes, providing a solid foundation for the light signal detection module 4 to accurately perceive the changes in light signal intensity. In turn, the control processing module 6 can accurately calculate the concentration of the measured gas based on the corresponding relationship between the light signal intensity and the gas concentration through the preset gas characteristic model, which strongly supports the efficient and accurate operation of the entire gas sensor in gas detection tasks.

[0084] In this embodiment, the silicon-based wideband pass filter can process a wider range of optical signals and has a wider range of application scenarios. For example, it has more advantages in optical detection systems that need to detect optical signals of multiple wavelengths.

[0085] In some embodiments, the broadband filter element 5 includes an adaptive filter module, which is used to adjust the transmittance according to the gas type determination information, and the adaptive filter module includes liquid crystal or electrochromic material.

[0086] In the design of this gas sensor, the adaptive filtering module in the broadband filter element 5 provides key support for improving detection flexibility and accuracy. When the gas type determination module 1 receives the user input to determine the type of gas being measured, the information is passed to the adaptive filtering module.

[0087] The adaptive filter module then adjusts its transmittance based on the identified gas type. This functionality relies on the liquid crystal or electrochromic material it contains. Liquid crystal materials exhibit unique optical anisotropy. Under the influence of an electric field or other external conditions, their molecular arrangement changes, resulting in changes in transmittance for different wavelengths of light. Electrochromic materials, on the other hand, can alter their optical absorption properties in response to electrical signals, enabling adjustable transmittance. Different gases have distinct characteristic absorption bands. By adjusting the transmittance through the adaptive filter module, the intensity and wavelength range of the target infrared light signal can be optimized to best suit the specific gas detection requirements. For example, when detecting a gas with strong absorption at a specific wavelength, the adaptive filter module reduces the transmittance of light near that wavelength to prevent detector saturation due to excessive light signals. For gases with weaker absorption, the transmittance is appropriately increased to enhance the light signal, ensuring detection accuracy and sensitivity. This further improves the adaptability and reliability of the gas sensor for multi-gas detection.

[0088] For example, taking the commonly used nematic liquid crystal as an example, its molecules are arranged in an orderly manner in the natural state, and have a certain initial transmittance for the target infrared light signal of 8μm to 14μm. After receiving the type determination information of the specific gas to be detected (such as carbon dioxide, which has absorption characteristics in this wavelength range), the arrangement direction of the liquid crystal molecules is changed by applying an external electric field. This change causes the optical properties of the liquid crystal to change for light with a wavelength of 8μm to 14μm, and the transmittance can be maintained at more than 80%. Specifically, the adjustment of the molecular arrangement angle under the action of the electric field optimizes the propagation path of light inside the liquid crystal, so that the target infrared light signal can pass through with appropriate intensity, ensuring that when interacting with the carbon dioxide gas in the gas chamber 2, the light signal intensity can fully reflect the gas's absorption characteristics for light, and will not affect the subsequent detection accuracy due to being too strong or too weak, thereby providing good optical conditions for accurately detecting the carbon dioxide concentration.

[0089] Regarding electrochromic materials, tungsten oxide (WO3) is used as the electrochromic material in the adaptive filtering module to explain its operating principle. In its initial state, the tungsten oxide film exhibits certain optical properties for target infrared light signals ranging from 8μm to 14μm, and its transmittance remains at a certain level when no voltage is applied. When it is necessary to detect a gas with absorption characteristics within this wavelength range (such as nitrous oxide), a specific voltage is applied to the tungsten oxide film based on the gas type. The voltage changes the electron distribution within the tungsten oxide, which in turn changes its absorption characteristics for infrared light with wavelengths from 8μm to 14μm, allowing the transmittance to be adjusted. By precisely controlling the voltage, the transmittance can be stabilized at above 80%, ensuring that the target infrared light signal of sufficient intensity enters gas chamber 2 and interacts with the nitrous oxide gas. This adjustability of the transmittance enables the sensor to optimize the light signal according to the detection requirements of different gases, thereby more accurately calculating the nitrous oxide gas concentration based on changes in light signal intensity, effectively improving the gas sensor's performance in detecting specific gases.

[0090] In some embodiments, the gas type determination module 1 further includes a voice recognition module, which is configured to receive a voice signal sent by the user and recognize the voice signal to obtain the gas type determination information.

[0091] The voice recognition module of the Gas Specifier Module 1 provides users with a convenient and efficient operation method. This module plays a key role in work environments where users may be busy with other tasks or find it inconvenient to manually enter gas type information. It incorporates advanced voice processing algorithms and acoustic models to sensitively capture user voice signals. Upon receiving a voice signal, the module quickly initiates a recognition process, accurately comparing the voice signal with pre-stored voice templates for various gas names and related commands. Through complex signal analysis and pattern matching, it accurately identifies the gas type information contained in the voice.

[0092] For example, when the user says "detect carbon dioxide concentration", the voice recognition module can quickly parse the voice content, identify "carbon dioxide" as the target gas type, and transmit this confirmation information to the control processing module 6 in a timely manner, so that the entire gas sensor system can quickly adjust the working parameters according to the user's voice instructions and realize the detection of the corresponding gas concentration, which greatly improves the convenience and efficiency of operation, and is especially suitable for complex working scenarios and situations where the detection gas type needs to be quickly switched.

[0093] In some embodiments, the gas sensor further includes a display module 8 connected to the control processing module 6 for displaying the detected concentration of the gas being measured.

[0094] Once the control processing module 6 completes the calculation of the measured gas concentration, it immediately transmits the detected concentration data to the display module 8. The display module 8 uses a high-definition display screen, which can clearly and accurately display the detected concentration value of the measured gas in both strong light and low light environments.

[0095] For example, in an industrial production environment, the operator can clearly read the precise concentration value of a certain harmful gas (such as carbon monoxide) in the current environment from the display module 8, so as to promptly judge whether the environment is safe and whether corresponding protective or treatment measures need to be taken.

[0096] At the same time, the display module 8 can also present data in different formats (such as digital display, chart display, etc.) according to user needs, making it easier for users to record and analyze data. In addition, for some application scenarios that require long-term monitoring of gas concentration changes, the display module 8 can also update data in real time, showing the concentration change trend over time in the form of a dynamic curve, providing strong support for users to fully understand the dynamic situation of gas concentration and ensuring the effective communication and intuitive presentation of gas sensor detection results.

[0097] The present invention also provides a method for detecting gas concentration using the gas sensor provided in the above embodiment. The method includes the following steps:

[0098] S1, placing the gas sensor in the target area.

[0099] S2, setting the gas type of the gas to be measured on the gas sensor.

[0100] S3, after a set time has passed, obtaining the detection concentration of the measured gas from the gas sensor.

[0101] In this embodiment, the method begins by precisely placing the gas sensor in the target area—the specific space where the gas concentration needs to be measured, such as near a specific production process on a factory floor, around a specific experimental device in a laboratory, or at an indoor air quality monitoring point. The choice of placement is crucial; it ensures that the sensor has sufficient contact with the gas being measured within the target area to avoid detection errors caused by improper placement.

[0102] Next, set the type of gas to be measured on the gas sensor. This can be done in a variety of ways, such as using the physical buttons on the sensor, selecting the corresponding gas type through the software interface on the device connected to the sensor, or using the voice recognition module to directly speak the gas name to complete the setting. Accurately setting the gas type is a key prerequisite for subsequent detection. Because different gases have different absorption spectra and characteristics, the sensor needs to call the corresponding internal parameters and algorithms for detection based on the set gas type.

[0103] Finally, after a pre-set period of time, the detected concentration of the measured gas is obtained from the gas sensor. The length of the set time depends on many factors, including the size of the target area, the gas diffusion rate, the response time of the sensor, and the required detection accuracy. For example, in a well-ventilated and small indoor environment, it may take a short time for the gas to be evenly distributed and reach a stable state. In this case, the set time can be relatively short; in large industrial plants or complex environments with poor ventilation, a longer time may be required to ensure that the test results can accurately reflect the actual gas concentration. After obtaining the detected concentration, users can record, analyze, or further process the data according to actual needs, such as determining whether the environment meets safety standards, evaluating whether gas emissions during the production process meet standards, etc., thereby providing strong data support for relevant decisions.

[0104] The method of this embodiment applies the gas sensor provided in the above embodiment to achieve the beneficial effects of the above gas sensor, which will not be described in detail here.

[0105] As described above, the above embodiments are only used to illustrate the technical solutions of the present invention, rather than to limit the same. Although the present invention has been described in detail with reference to the above embodiments, those skilled in the art should understand that the technical solutions described in the above embodiments can still be modified, or some of the technical features thereof can be replaced by equivalents. However, these modifications or replacements do not deviate the essence of the corresponding technical solutions from the scope of the technical solutions of the embodiments of the present invention.

Claims

1. A gas sensor capable of switching the type of gas being measured, characterized in that: It includes a gas type determination module, a gas chamber, a light source, an optical signal detection module, a broadband filter element, an environment detection module and a control processing module; The gas type determination module is used to receive gas type determination information of the measured gas input by the user, and transmit the gas type determination information to the control processing module; The gas chamber is used to accommodate the gas to be measured, the light source is arranged on the light incident side of the gas chamber, and the optical signal detection module is arranged on the light exit side of the gas chamber; The broadband filter element is provided at the signal transmitting end of the light source, and is used to filter out the target infrared light signal within a set wavelength range in the detection light signal emitted by the light source, so that the target infrared light signal passes through the gas to be measured and is emitted to the optical signal detection module; The optical signal detection module is used to convert the received target infrared light signal into an optical signal intensity digital signal, and transmit the optical signal intensity digital signal to the control processing module; The control processing module is used to determine the target gas characteristic model corresponding to the measured gas from a preset gas characteristic model library based on the gas type determination information, and determine the detection concentration of the measured gas based on the optical signal intensity digital signal and the target gas characteristic model, wherein the target gas characteristic model is used to characterize the corresponding relationship between the optical signal intensity and the gas concentration; The environment detection module is provided in the gas chamber, and is used to detect the environment information in the gas chamber and send the environment information to the control processing module. The control processing module is also used to compensate the detected concentration according to the environment information to obtain the environment compensation concentration of the measured gas; The control processing module is specifically used to input the environmental information into a preset environmental compensation model to obtain an environmental compensation factor, and determine the environmental compensation concentration according to the environmental compensation factor and the detected concentration; The environmental information includes environmental temperature, environmental humidity and environmental pressure, and the environmental compensation model includes: Wherein, C is the detection concentration, C corrected is the environmental compensation concentration, F ( T,H,P ) is the environmental compensation factor, T is the ambient temperature, H is the ambient humidity, P is the ambient air pressure, T 0 is the reference temperature, H 0 is the reference humidity, P 0 is the reference pressure, α, β, γ are experimental parameters, e is a natural constant.

2. The gas sensor according to claim 1, wherein The broadband filter element includes a silicon-based broadband pass filter, and the transmittance of the silicon-based broadband pass filter to the target infrared light signal is above 80%.

3. The gas sensor according to claim 2, characterized in that The wavelength of the target infrared light signal is 8um to 14um.

4. The gas sensor according to claim 1, wherein The broadband filter element includes an adaptive filter module, which is used to adjust the transmittance according to the gas type determination information. The adaptive filter module includes liquid crystal or electrochromic material.

5. The gas sensor according to claim 1, wherein The gas type determination module further includes a voice recognition module, which is configured to receive a voice signal sent by the user and recognize the voice signal to obtain the gas type determination information.

6. The gas sensor according to claim 1, wherein It also includes a display module connected to the control processing module, which is used to display the detection concentration of the measured gas.

7. A gas concentration detection method, characterized in that: Using the gas sensor according to any one of claims 1 to 6, the method comprises: placing the gas sensor in a target area; Setting the gas type of the gas to be measured on the gas sensor; After a set time has passed, the detection concentration of the measured gas is obtained from the gas sensor.

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