WO2022127144A1 - 一种红外吸收型二氧化碳浓度检测装置 - Google Patents
一种红外吸收型二氧化碳浓度检测装置 Download PDFInfo
- Publication number
- WO2022127144A1 WO2022127144A1 PCT/CN2021/111994 CN2021111994W WO2022127144A1 WO 2022127144 A1 WO2022127144 A1 WO 2022127144A1 CN 2021111994 W CN2021111994 W CN 2021111994W WO 2022127144 A1 WO2022127144 A1 WO 2022127144A1
- Authority
- WO
- WIPO (PCT)
- Prior art keywords
- circuit
- infrared light
- light source
- carbon dioxide
- infrared
- Prior art date
Links
- CURLTUGMZLYLDI-UHFFFAOYSA-N Carbon dioxide Chemical compound O=C=O CURLTUGMZLYLDI-UHFFFAOYSA-N 0.000 title claims abstract description 136
- 238000001514 detection method Methods 0.000 title claims abstract description 98
- 229910002092 carbon dioxide Inorganic materials 0.000 title claims abstract description 68
- 239000001569 carbon dioxide Substances 0.000 title claims abstract description 68
- 230000003287 optical effect Effects 0.000 claims abstract description 8
- 238000010521 absorption reaction Methods 0.000 claims description 36
- 238000005259 measurement Methods 0.000 claims description 22
- 238000006243 chemical reaction Methods 0.000 claims description 16
- 238000012360 testing method Methods 0.000 abstract description 4
- 238000000034 method Methods 0.000 description 16
- 230000006641 stabilisation Effects 0.000 description 4
- 238000011105 stabilization Methods 0.000 description 4
- 238000010586 diagram Methods 0.000 description 3
- 238000011161 development Methods 0.000 description 2
- 238000009776 industrial production Methods 0.000 description 2
- 238000012986 modification Methods 0.000 description 2
- 230000004048 modification Effects 0.000 description 2
- 239000003381 stabilizer Substances 0.000 description 2
- 238000000862 absorption spectrum Methods 0.000 description 1
- 238000012271 agricultural production Methods 0.000 description 1
- 230000003321 amplification Effects 0.000 description 1
- 230000033228 biological regulation Effects 0.000 description 1
- 239000003990 capacitor Substances 0.000 description 1
- 230000006012 detection of carbon dioxide Effects 0.000 description 1
- 230000009977 dual effect Effects 0.000 description 1
- 230000000694 effects Effects 0.000 description 1
- 230000007613 environmental effect Effects 0.000 description 1
- 238000004817 gas chromatography Methods 0.000 description 1
- 230000009931 harmful effect Effects 0.000 description 1
- 239000000463 material Substances 0.000 description 1
- 238000003199 nucleic acid amplification method Methods 0.000 description 1
- 239000002245 particle Substances 0.000 description 1
- 230000029553 photosynthesis Effects 0.000 description 1
- 238000010672 photosynthesis Methods 0.000 description 1
- 230000000750 progressive effect Effects 0.000 description 1
- 239000002994 raw material Substances 0.000 description 1
- 230000001105 regulatory effect Effects 0.000 description 1
- 239000000126 substance Substances 0.000 description 1
Images
Classifications
-
- G—PHYSICS
- G01—MEASURING; TESTING
- G01N—INVESTIGATING OR ANALYSING MATERIALS BY DETERMINING THEIR CHEMICAL OR PHYSICAL PROPERTIES
- G01N21/00—Investigating or analysing materials by the use of optical means, i.e. using sub-millimetre waves, infrared, visible or ultraviolet light
- G01N21/17—Systems in which incident light is modified in accordance with the properties of the material investigated
- G01N21/25—Colour; Spectral properties, i.e. comparison of effect of material on the light at two or more different wavelengths or wavelength bands
- G01N21/31—Investigating relative effect of material at wavelengths characteristic of specific elements or molecules, e.g. atomic absorption spectrometry
- G01N21/35—Investigating relative effect of material at wavelengths characteristic of specific elements or molecules, e.g. atomic absorption spectrometry using infrared light
- G01N21/3504—Investigating relative effect of material at wavelengths characteristic of specific elements or molecules, e.g. atomic absorption spectrometry using infrared light for analysing gases, e.g. multi-gas analysis
-
- G—PHYSICS
- G01—MEASURING; TESTING
- G01N—INVESTIGATING OR ANALYSING MATERIALS BY DETERMINING THEIR CHEMICAL OR PHYSICAL PROPERTIES
- G01N21/00—Investigating or analysing materials by the use of optical means, i.e. using sub-millimetre waves, infrared, visible or ultraviolet light
- G01N21/01—Arrangements or apparatus for facilitating the optical investigation
Definitions
- the present application relates to the technical field of sensor detection circuits, in particular to an infrared absorption type carbon dioxide concentration detection device.
- the current detection methods of carbon dioxide concentration mainly include sensor method, chemical method, gas chromatography, etc. Among these methods, sensor method is widely used in industrial production and environmental management due to its simple operation, low price and high accuracy. Among them, the sensor based on the infrared absorption method to detect the carbon dioxide concentration has attracted much attention due to its high measurement accuracy, long life and low drift.
- the principle of infrared absorption method to detect carbon dioxide concentration is that when infrared light of a specific wavelength is irradiated on the gas to be measured, the infrared light of a specific wavelength is absorbed by carbon dioxide molecules.
- the concentration of carbon dioxide in the gas to be measured can be measured by changing the intensity of infrared light of a specific wavelength before and after the gas to be measured.
- the detection should be carried out under the condition that the intensity and luminous efficiency of the infrared light emitted by the infrared light source remain unchanged.
- the temperature of the light source will increase after a long time of emitting light, which will reduce the luminous efficiency of the light source, which will directly affect the detection accuracy.
- the purpose of this application is to provide a kind of infrared absorption type carbon dioxide concentration detection device, for improving the detection accuracy when detecting carbon dioxide concentration based on the principle of infrared absorption method.
- an infrared absorption type carbon dioxide concentration detection device comprising: an infrared light source circuit, a gas chamber containing the gas to be measured, and an infrared signal detection circuit;
- the infrared light source circuit includes: an infrared light source drive circuit, an infrared light source, a voltage measurement circuit, an adjustable resistor and a first processor; the output end of the infrared light source drive circuit is connected to the drive end of the infrared light source; the The adjustable resistance is set in the circuit where the infrared light source is located; the first end of the voltage measurement circuit is connected to the infrared light source, and the second end of the voltage measurement circuit is connected to the input end of the first processor; The control end of the infrared light source driving circuit is connected to the first output end of the first processor, and the control end of the adjustable resistor is connected to the second output end of the first processor;
- the first processor is configured to adjust the resistance value of the adjustable resistor according to the voltage across the infrared light source measured by the voltage measurement circuit to maintain the stability of the voltage across the infrared light source;
- the first end of the air chamber is fixed to the emission end of the infrared light source, the second end of the air chamber is fixed to the detection end of the infrared signal detection circuit, and a filter is arranged in the air chamber.
- the adjustable resistor is specifically connected in series between the output end of the infrared light source drive circuit and the drive end of the infrared light source.
- it also includes a power supply circuit for converting the input voltage into the required voltage of the infrared light source driving circuit;
- the input end of the power supply circuit is connected to the AC power supply, and the output end of the power supply circuit is connected to the input end of the infrared light source driving circuit.
- the power supply circuit specifically includes: a transformer, a rectifier circuit and a filter circuit;
- the input end of the transformer is used to connect the AC power supply
- the output end of the transformer is connected to the input end of the rectifier circuit
- the output end of the rectifier circuit is connected to the input end of the filter circuit, so The output end of the filter circuit is connected to the input end of the infrared light source driving circuit.
- the infrared light source driving circuit is specifically constructed based on a voltage regulator chip.
- the optical filter specifically includes a detection optical filter and a reference optical filter.
- the detection light filter is specifically a filter with a wavelength band of 4.26 ⁇ m.
- the reference light filter is specifically a filter with a wavelength band of 4.2 ⁇ m.
- the infrared signal detection circuit specifically includes: a photoelectric detection circuit, an amplifier circuit, an analog-to-digital conversion circuit, and a second processor;
- the detection end of the photoelectric detection circuit is fixed on the second end of the gas chamber, the output end of the photoelectric detection circuit is connected with the input end of the amplifying circuit, and the output end of the amplifying circuit is connected with the module
- the first end of the digital conversion circuit is connected, and the second end of the analog-to-digital conversion circuit is connected with the input end of the second processor;
- the second processor is configured to calculate and obtain a second light intensity value of the infrared light after passing through the air chamber according to the electrical signal received from the second end of the analog-to-digital conversion circuit, and according to the second infrared light intensity
- the carbon dioxide concentration value of the gas to be measured is obtained by calculating the difference between the value and the first light intensity value of the infrared light emitted by the infrared light source.
- it also includes an RS485 communicator connected to the output end of the second processor;
- the second processor is further configured to send the carbon dioxide concentration value of the gas to be measured to the upper computer through the RS485 communicator.
- the infrared absorption type carbon dioxide concentration detection device includes: an infrared light source circuit, a gas chamber containing the gas to be measured, and an infrared signal detection circuit.
- the first end of the gas chamber is fixed to the emission end of the infrared light source, and the The second end is fixed on the detection end of the infrared signal detection circuit, and a filter is arranged in the air chamber.
- the infrared light source circuit includes an infrared light source drive circuit, an infrared light source, and a voltage measurement circuit composed of a voltage measurement circuit, an adjustable resistor and a first processor.
- the first processor adjusts the voltage at both ends of the infrared light source measured by the voltage measurement circuit.
- the resistance value of the resistor can be adjusted to maintain the stability of the voltage across the infrared light source, thereby maintaining the luminous efficiency of the infrared light emitted by the infrared light source and the stability of the light intensity value, and improving the accuracy of carbon dioxide concentration testing.
- Fig. 1 is the structural representation of a kind of infrared absorption type carbon dioxide concentration detection device that the embodiment of the application provides;
- FIG. 2 is a circuit diagram of a power supply circuit provided by an embodiment of the present application.
- 101 is an infrared light source drive circuit
- 102 is an infrared light source
- 103 is a voltage measurement circuit
- 104 is an adjustable resistor
- 105 is a first processor
- 200 is an air chamber
- 301 is a photoelectric detection circuit
- 302 is an amplifier circuit
- 303 It is an analog-to-digital conversion circuit
- 304 is a second processor
- 305 is an RS485 communicator
- 400 is a power supply circuit.
- the core of the present application is to provide an infrared absorption type carbon dioxide concentration detection device, which is used to improve the detection accuracy when detecting the carbon dioxide concentration based on the principle of the infrared absorption method.
- FIG. 1 is a schematic structural diagram of an infrared absorption type carbon dioxide concentration detection device according to an embodiment of the present application.
- the infrared absorption type carbon dioxide concentration detection device includes: an infrared light source circuit, a gas chamber 200 containing a gas to be measured, and an infrared signal detection circuit;
- the infrared light source circuit includes: an infrared light source drive circuit 101, an infrared light source 102, a voltage measurement circuit 103, an adjustable resistor 104 and a first processor 105; the output end of the infrared light source drive circuit 101 is connected to the drive end of the infrared light source 102;
- the adjustable resistor 104 is set in the circuit where the infrared light source 102 is located; the first end of the voltage measuring circuit 103 is connected to the infrared light source 102, and the second end of the voltage measuring circuit 103 is connected to the input end of the first processor 105; the infrared light source driving circuit 101
- the control terminal of 1 is connected to the first output terminal of the first processor 105, and the control terminal of the adjustable resistor 104 is connected to the second output terminal of the first processor 105;
- the first processor 105 is configured to adjust the resistance value of the adjustable resistor 104 according to the voltage at both ends of the infrared light source 102 measured by the voltage measurement circuit 103 to maintain the stability of the voltage at both ends of the infrared light source 102;
- the first end of the air chamber 200 is fixed to the emission end of the infrared light source 102 , the second end of the air chamber 200 is fixed to the detection end of the infrared signal detection circuit, and the air chamber 200 is provided with a filter.
- the circuit resistance will change, the luminous efficiency of the infrared light source 102 will be affected, and the measurement accuracy will be affected.
- the detection device uses the voltage measurement circuit 103 to measure the voltage across the infrared light source 102 in real time, and feeds it back to the first processor 105, and the first processor 105 controls the resistance value of the adjustable resistor 104 to maintain the stability of the voltage across the infrared light source 102, and then The consistency of the luminous efficiency and light intensity of the infrared light source 102 is maintained, thereby improving the accuracy of the entire detection device.
- the infrared absorption type carbon dioxide concentration detection device is mainly composed of an infrared light source circuit, a gas chamber 200 containing the gas to be measured, and an infrared signal detection circuit.
- the infrared light source circuit is mainly composed of an infrared light source drive circuit 101 , an infrared light source 102 , a voltage measurement circuit 103 , an adjustable resistor 104 and a first processor 105 .
- the infrared light source 102 can be an infrared light source 102 that emits infrared light of 1-20 ⁇ m.
- the infrared light source 102 is driven by the infrared light source driving circuit 101 to emit infrared light.
- a resistance adjustment loop is formed by a voltage measurement circuit 103 , an adjustable resistor 104 and a first processor 105 , as shown in FIG. between.
- the first processor 105 monitors the voltage across the infrared light source 102 in real time based on the voltage measurement circuit 103, compares the real-time voltage value with the set voltage value, and controls the adjustable resistor 104 for adjustment according to the error. In addition, the first processor 105 can also receive the adjustment of the set voltage value, and change the voltage across the infrared light source 102 by adjusting the resistance value of the adjustable resistor 104 . Normally, the adjustable resistor 104 is controlled by the output voltage of the infrared light source driving circuit 101 and the first processor 105, so that the voltage across the infrared light source 102 is maintained at about 5V.
- the infrared light source driving circuit 101 can be constructed based on a voltage regulator chip.
- a DC voltage stabilizer circuit is formed by a voltage stabilizer chip, and a stable voltage is provided to the infrared light source 102, so that the light intensity emitted by the infrared light source 102 is kept stable, and the measurement accuracy of the device is improved.
- the gas chamber 200 is used to hold the gas to be tested, and should be made of opaque materials as much as possible. After filling with the gas to be tested, the gas chamber 200 is sealed.
- the infrared light source 102 is fixed on the first end of the air chamber 200 .
- the infrared light source 102 can be arranged in the air chamber 200 to avoid interference by air.
- Carbon dioxide can absorb infrared light of a specific wavelength, and a filter that can transmit infrared light of a specific wavelength is arranged in the gas chamber 200, and the infrared light passes through the gas to be tested and the filter in the gas chamber 200 to achieve infrared signal detection.
- the infrared signal detection circuit can perform photoelectric detection to determine the light intensity value of the infrared light, and the carbon dioxide concentration in the gas to be measured can be calculated by comparing with the light intensity value of the infrared light emitted by the known infrared light source 102 .
- the filter can be arranged at the second end of the air chamber 200 before the infrared signal detection circuit.
- the filter specifically includes a detection light filter and a reference light filter.
- the detection light filter is used to filter the infrared light that can be absorbed by carbon dioxide
- the reference light filter is used to filter the infrared light that cannot be absorbed by carbon dioxide.
- the detection light filter can use a 4.26 ⁇ m wavelength filter
- the reference light filter can use a 4.2 ⁇ m wavelength filter.
- carbon dioxide has an absorption spectrum of a specific wavelength, and its absorption intensity is related to the concentration of the gas. By detecting the intensity of the absorption, the concentration of the gas can be measured.
- the absorption intensity of a specific wavelength determines the intensity value of the absorbed light by detecting the initial light intensity value, the reference light intensity value, and the light intensity value passing through the gas to be tested.
- the infrared absorption type carbon dioxide concentration detection device may use dual infrared light sources 102 to detect the carbon dioxide concentration in the gas to be measured.
- the consistency of the luminous efficiency and luminous intensity of the two infrared light sources 102 can be better maintained.
- the infrared signal detection circuit may specifically include: a photoelectric detection circuit 301 , an amplification circuit 302 , an analog-to-digital conversion circuit 303 and a second processor 304 ;
- the detection end of the photoelectric detection circuit 301 is fixed at the second end of the gas chamber 200 , the output end of the photoelectric detection circuit 301 is connected to the input end of the amplifying circuit 302 , and the output end of the amplifying circuit 302 is connected to the first end of the analog-to-digital conversion circuit 303 .
- the second end of the analog-to-digital conversion circuit 303 is connected to the input end of the second processor 304;
- the second processor 304 is configured to calculate and obtain the second light intensity value of the infrared light after passing through the air chamber 200 according to the electrical signal received from the second end of the analog-to-digital conversion circuit 303, and according to the second infrared light intensity value and the infrared light source
- the carbon dioxide concentration value of the gas to be measured is obtained by calculating the difference between the first light intensity values of the infrared light emitted by 102 .
- the infrared signal detection circuit is used to convert the infrared light passing through the air chamber 200 into an electrical signal for measurement, and obtain a light intensity value.
- the detection end of the photoelectric detection circuit 301 in the infrared signal detection circuit is fixed to the second end of the gas chamber 200 to receive the detection light and the reference light after the reaction.
- the infrared light emitted by the infrared light source 102 passes through the gas to be measured in the gas chamber 200, and after passing through the detection light filter and the reference light respectively, the carbon dioxide in the gas to be measured absorbs the infrared light with a wavelength of 4.26 ⁇ m, and the photoelectric
- the detection circuit 301 receives the reacted detection light and the reference light, respectively detects the second light intensity value of the two, and compares it with the first light intensity value emitted by the infrared light source 102, and calculates the gas to be measured by the two error values. Carbon dioxide concentration value.
- the photoelectric detection circuit 301 can use a photodiode to convert the absorbed optical signal into a corresponding electrical signal. Since the electrical signal is weak, the electrical signal needs to be amplified by the amplifying circuit 302, and then filtered by a filter to filter out the interference signal, and then the analog-digital signal needs to be amplified.
- the conversion circuit 303 converts the digital signal into the second processor 304 .
- the second processor 304 calculates and obtains the carbon dioxide concentration value of the gas to be measured according to the preloaded algorithm.
- Both the first processor 105 and the second processor 304 may use a single-chip microcomputer.
- the second processor 304 may also be configured to store and transmit the calculated carbon dioxide concentration value.
- the infrared absorption type carbon dioxide concentration detection device provided in the embodiment of the present application may further include a communicator connected to the output end of the second processor 304 , and the communicator may adopt the RS485 communicator 305 .
- the second processor 304 is further configured to send the carbon dioxide concentration value of the gas to be measured to the upper computer through the RS485 communicator 305 .
- FIG. 2 is a circuit diagram of a power supply circuit provided by an embodiment of the present application.
- the infrared absorption type carbon dioxide concentration detection device provided by the embodiment of the present application further includes a voltage for converting the input voltage into the required voltage of the infrared light source driving circuit 101101 power circuit 400;
- the input end of the power supply circuit 400 is connected to the AC power supply, and the output end of the power supply circuit 400 is connected to the input end of the infrared light source driving circuit 101101 .
- the power module may specifically include: a transformer, a rectifier circuit and a filter circuit;
- the input end of the transformer is used to connect the AC power supply, the output end of the transformer is connected to the input end of the rectifier circuit, the output end of the rectifier circuit is connected to the input end of the filter circuit, and the output end of the filter circuit is connected to the input end of the infrared light source drive circuit 101101 end connection.
- the power module converts 220V AC into low-voltage DC, and provides 6-25V DC voltage for the infrared light source drive circuit 101101.
- the first end of the transformer T is connected to a 220V AC power supply (220V AC), and the second end (A1, A2 sides) of the transformer T is connected to the diode D1, D2, D3, D4.
- a rectifier circuit, the output end of the rectifier circuit is connected to a filter circuit composed of capacitors, and the second end of the filter circuit is connected to the input end of the infrared light source drive circuit 101101 .
- a workflow for measuring carbon dioxide concentration is as follows:
- the external 220V alternating current is connected to the infrared absorption type carbon dioxide concentration detection device provided in the embodiment of the present application, the alternating voltage of the grid is changed into the alternating voltage required by the rectification circuit through the transformer, and then the output voltage of the second end is passed through the rectification circuit.
- the rectifier diode becomes a DC current, and then the interference current component in the unidirectional pulse voltage is filtered out by the filter circuit, and the DC voltage in the range of 6-25V is provided to the infrared light source drive circuit 101101.
- the DC voltage is regulated by the red light source drive circuit.
- the voltage stabilization function of the chip provides a stable voltage to the red light source.
- the load in the circuit changes, and the voltage across the infrared light source 102 is monitored in real time through the voltage detection circuit, and fed back to the first processor 105, which controls the adjustable resistor 104 to achieve this.
- the function of voltage stabilization combined with the voltage stabilization chip to achieve double voltage stabilization, ensures the stability of the voltage across the light source, thereby ensuring the consistent luminous intensity of the infrared light source 102, and improving the stability of the sensor.
- the stable infrared light enters the fixed-length gas chamber 200, the infrared light with a wavelength of 4.26 ⁇ m is absorbed by the carbon dioxide in the gas chamber 200, the light with a wavelength of 4.2 ⁇ m passes through the carbon dioxide, and passes through the detection light filter with a wavelength of 4.26 ⁇ m and a 4.2 ⁇ m reference light filter, the second light intensity values of the detection light and the reference light can be measured.
- the photoelectric detection circuit 301 the detected second light intensity value of the detection light and the second light intensity value of the reference light are converted into corresponding electrical signals.
- the filter circuit filters out the interference signal.
- the amplified and filtered electrical signal is processed by analog-to-digital conversion to obtain a digital signal, which is input to the second processor 304 .
- the second processor 304 uses a preloaded algorithm to compare the second light intensity value of the detection light with the second light intensity value of the reference light according to the first light intensity value of the infrared light generated by the infrared light source 102, and calculates to obtain the to-be-measured Carbon dioxide concentration in the gas.
- the second processor 304 stores and transmits the carbon dioxide concentration in the gas to be measured, and sends the carbon dioxide concentration in the gas to be measured to the host computer through the RS485 communicator 305 .
Landscapes
- Physics & Mathematics (AREA)
- Health & Medical Sciences (AREA)
- Life Sciences & Earth Sciences (AREA)
- Chemical & Material Sciences (AREA)
- Analytical Chemistry (AREA)
- Biochemistry (AREA)
- General Health & Medical Sciences (AREA)
- General Physics & Mathematics (AREA)
- Immunology (AREA)
- Pathology (AREA)
- Spectroscopy & Molecular Physics (AREA)
- Investigating Or Analysing Materials By Optical Means (AREA)
Abstract
一种红外吸收型二氧化碳浓度检测装置，包括：红外光源电路、置有待测气体的气室和红外信号检测电路，气室的第一端固定于红外光源的发射端，气室的第二端固定于红外信号检测电路的检测端，气室中设有滤光片。红外光源电路包括红外光源驱动电路、红外光源，还包括由电压测量电路、可调电阻和第一处理器组成的电压测量回路，第一处理器根据电压测量电路测得的红外光源两端的电压调整可调电阻的阻值以维持红外光源两端电压的稳定，从而保持红外光源发射红外光的发光效率和光强度值的稳定性，提高二氧化碳浓度测试准确性。
Description
本申请要求于2020年12月14日提交中国专利局、申请号为202011466218.8、发明名称为“一种红外吸收型二氧化碳浓度检测装置”的中国专利申请的优先权，其全部内容通过引用结合在本申请中。
本申请涉及传感器检测电路技术领域，特别是涉及一种红外吸收型二氧化碳浓度检测装置。
随着人类社会的发展和科学技术的发展，工业生产规模越来越大，二氧化碳的排放量也越来越大。二氧化碳浓度的增加可能会造成有害影响，如温室效应和土地荒漠化。二氧化碳也有有利的一面，如能够作为光合作用的原料，现代农业生产通过在塑料大棚中通入二氧化碳提高作物的收成。所以对二氧化碳浓度的检测是非常重要的。目前的二氧化碳浓度的检测方法主要包括传感器法、化学法、气相色谱法等，在这些方法中由于传感器法具有操作简单、价格低廉、准确性高而广泛应用于工业生产和环境治理中。其中，利用基于红外吸收法检测二氧化碳浓度原理的传感器因其测量准确度高、寿命长、漂移性低而备受关注。
红外吸收法检测二氧化碳浓度的原理是当特定波长的红外光照射到待测气体上，特定波长的红外光被二氧化碳分子吸收，二氧化碳的浓度越高，吸收的量就越多，透过检测透过待测气体前后特定波长的红外光强度的变化，即可测得待测气体中二氧化碳的浓度。为保证检测精度，应当在红外光源发射的红外光强度和发光效率不变的条件下进行检测。然而，目前市售的红外二氧化碳浓度检测传感器，其光源在长时间发光后温度会升高，随之降低了光源的发光效率，这将直接影响检测的准确性。
发明内容
本申请的目的是提供一种红外吸收型二氧化碳浓度检测装置，用于提 高基于红外吸收法原理检测二氧化碳浓度时的检测精度。
为解决上述技术问题，本申请提供一种红外吸收型二氧化碳浓度检测装置，包括：红外光源电路、置有待测气体的气室和红外信号检测电路；
其中，所述红外光源电路包括：红外光源驱动电路、红外光源、电压测量电路、可调电阻和第一处理器；所述红外光源驱动电路的输出端与所述红外光源的驱动端连接；所述可调电阻设于所述红外光源所在电路；所述电压测量电路的第一端与所述红外光源连接，所述电压测量电路的第二端与所述第一处理器的输入端连接；所述红外光源驱动电路的控制端与所述第一处理器的第一输出端连接，所述可调电阻的控制端与所述第一处理器的第二输出端连接；
所述第一处理器用于根据所述电压测量电路测得的所述红外光源两端的电压调整所述可调电阻的阻值以维持所述红外光源两端电压的稳定；
所述气室的第一端固定于所述红外光源的发射端，所述气室的第二端固定于所述红外信号检测电路的检测端，所述气室中设有滤光片。
可选的，所述可调电阻具体串联于所述红外光源驱动电路的输出端与所述红外光源的驱动端之间。
可选的，还包括用于将输入电压转换为所述红外光源驱动电路的所需电压的电源电路；
所述电源电路的输入端连接交流电源，所述电源电路的输出端与所述红外光源驱动电路的输入端连接。
可选的，所述电源电路具体包括：变压器、整流电路和滤波电路；
其中，所述变压器的输入端用于连接所述交流电源，所述变压器的输出端与所述整流电路的输入端连接，所述整流电路的输出端与所述滤波电路的输入端连接，所述滤波电路的输出端与所述红外光源驱动电路的输入端连接。
可选的，所述红外光源驱动电路具体基于稳压芯片搭建而成。
可选的，所述滤光片具体包括检测光滤光片和参比光滤光片。
可选的，所述检测光滤光片具体为4.26μm波段的滤光片。
可选的，所述参比光滤光片具体为4.2μm波段的滤光片。
可选的，所述红外信号检测电路具体包括：光电检测电路、放大电路、模数转换电路和第二处理器；
其中，所述光电检测电路的检测端固定于所述气室的第二端，所述光电检测电路的输出端与所述放大电路的输入端连接，所述放大电路的输出端与所述模数转换电路的第一端连接，所述模数转换电路的第二端与所述第二处理器的输入端连接；
所述第二处理器用于根据自所述模数转换电路的第二端接收到的电信号计算得到经过所述气室后的红外光的第二光强度值，根据所述第二红外光强度值与所述红外光源发射的红外光的第一光强度值的差值计算得到所述待测气体的二氧化碳浓度值。
可选的，还包括与所述第二处理器的输出端连接的RS485通信器；
所述第二处理器还用于将所述待测气体的二氧化碳浓度值通过所述RS485通信器发送至上位机。
本申请所提供的红外吸收型二氧化碳浓度检测装置，包括：红外光源电路、置有待测气体的气室和红外信号检测电路，气室的第一端固定于红外光源的发射端，气室的第二端固定于红外信号检测电路的检测端，气室中设有滤光片。红外光源电路包括红外光源驱动电路、红外光源，还包括由电压测量电路、可调电阻和第一处理器组成的电压测量回路，第一处理器根据电压测量电路测得的红外光源两端的电压调整可调电阻的阻值以维持红外光源两端电压的稳定，从而保持红外光源发射红外光的发光效率和光强度值的稳定性，提高二氧化碳浓度测试准确性。
为了更清楚的说明本申请实施例或现有技术的技术方案，下面将对实施例或现有技术描述中所需要使用的附图作简单的介绍，显而易见地，下面描述中的附图仅仅是本申请的一些实施例，对于本领域普通技术人员来讲，在不付出创造性劳动的前提下，还可以根据这些附图获得其他的附图。
图1为本申请实施例提供的一种红外吸收型二氧化碳浓度检测装置的 结构示意图；
图2为本申请实施例提供的一种电源电路的电路图；
其中，101为红外光源驱动电路，102为红外光源，103为电压测量电路，104为可调电阻，105为第一处理器，200为气室，301为光电检测电路，302为放大电路，303为模数转换电路，304为第二处理器，305为RS485通信器，400为电源电路。
本申请的核心是提供一种红外吸收型二氧化碳浓度检测装置，用于提高基于红外吸收法原理检测二氧化碳浓度时的检测精度。
下面将结合本申请实施例中的附图，对本申请实施例中的技术方案进行清楚、完整地描述，显然，所描述的实施例仅仅是本申请一部分实施例，而不是全部的实施例。基于本申请中的实施例，本领域普通技术人员在没有做出创造性劳动前提下所获得的所有其他实施例，都属于本申请保护的范围。
图1为本申请实施例提供的一种红外吸收型二氧化碳浓度检测装置的结构示意图。
如图1所示，本申请实施例提供的红外吸收型二氧化碳浓度检测装置包括：红外光源电路、置有待测气体的气室200和红外信号检测电路；
其中，红外光源电路包括：红外光源驱动电路101、红外光源102、电压测量电路103、可调电阻104和第一处理器105；红外光源驱动电路101的输出端与红外光源102的驱动端连接；可调电阻104设于红外光源102所在电路；电压测量电路103的第一端与红外光源102连接，电压测量电路103的第二端与第一处理器105的输入端连接；红外光源驱动电路101的控制端与第一处理器105的第一输出端连接，可调电阻104的控制端与第一处理器105的第二输出端连接；
第一处理器105用于根据电压测量电路103测得的红外光源102两端 的电压调整可调电阻104的阻值以维持红外光源102两端电压的稳定；
气室200的第一端固定于红外光源102的发射端，气室200的第二端固定于红外信号检测电路的检测端，气室200中设有滤光片。
针对基于红外吸收法检测二氧化碳浓度的装置会因为持续工作导致电路升温使电路阻值变化、影响红外光源102的发光效率、进而影响测量准确性的问题，本申请实施例提供的红外吸收型二氧化碳浓度检测装置采用电压测量电路103实时测量红外光源102两端的电压，反馈给第一处理器105，由第一处理器105控制可调电阻104的阻值来维持红外光源102两端电压的稳定，进而保持红外光源102的发光效率和光强的一致性，从而提高整个检测装置的准确度。
如图1所示，本申请实施例提供的红外吸收型二氧化碳浓度检测装置主要由红外光源电路、置有待测气体的气室200和红外信号检测电路几大部分组成。
其中，红外光源电路主要由：红外光源驱动电路101、红外光源102、电压测量电路103、可调电阻104和第一处理器105组成。红外光源102可以采用发射1-20μm红外光的红外光源102。由红外光源驱动电路101驱动红外光源102发射红外光。由电压测量电路103、可调电阻104和第一处理器105构成电阻调节回路，如图1所示，可以将可调电阻104串联于红外光源驱动电路101的输出端与红外光源102的驱动端之间。通过第一处理器105基于电压测量电路103实时监测红外光源102两端的电压，将实时电压值与设定电压值进行比对，根据误差控制可调电阻104进行调节。此外，第一处理器105还可以接收对设定电压值的调整，并通过调节可调电阻104的阻值来改变红外光源102两端的电压。通常情况下，通过红外光源驱动电路101输出电压和第一处理器105控制可调电阻104，使红外光源102两端电压维持在5V左右。
为进一步提高红外光源102两端电压的稳定性，红外光源驱动电路101可以基于稳压芯片搭建而成。通过稳压芯片构成直流稳压电路，给红外光源102提供稳定的电压，进而使红外光源102发射的光强度保持稳定，提高装置测量的准确性。
气室200用于盛放待测气体，应尽量采用不透光的材料。在充入待测气体后，将气室200密闭。如图1所示，将红外光源102固定于气室200的第一端，具体可以将红外光源102设置于气室200内，避免受到空气的干扰。二氧化碳可以吸收特定波长的红外光，将可透过特定波长的红外光的滤光片设于气室200中，红外光透过气室200中的待测气体和滤光片，达到红外信号检测电路，即可由红外信号检测电路进行光电检测确定红外光的光强度值，通过与已知的红外光源102发射的红外光的光强度值进行对比即可计算得到待测气体中的二氧化碳浓度。可以将滤光片设于气室200的第二端、红外信号检测电路之前。
为排除气室200可见度、颗粒物对检测的影响，滤光片具体包括检测光滤光片和参比光滤光片。其中，检测光滤光片用于滤过可被二氧化碳吸收的红外光，参比光滤光片用于滤过不可被二氧化碳吸收的红外光。在实际应用中，检测光滤光片可以采用4.26μm波段的滤光片，参比光滤光片可以采用4.2μm波段的滤光片。根据郎伯-比尔定律，二氧化碳有特定波长的吸收光谱，其吸收强度和气体的浓度有关，通过检测吸收的强度可就可测量气体的浓度。而特定波长的吸收强度通过检测初始光强度值、参比光强度值、穿过待测气体的光强度值来确定吸收光的强度值。
为了进一步提高二氧化碳浓度测试的准确性，本申请实施例提供的红外吸收型二氧化碳浓度检测装置可以采用双红外光源102来检测待测气体中二氧化碳的浓度。而通过本申请实施例提供的红外吸收型二氧化碳浓度检测装置中的电压调节回路，可以更好地保持两个红外光源102发光效率和发光强度的一致性。
如图1所示，在本申请实施例提供的红外吸收型二氧化碳浓度检测装置中，红外信号检测电路具体可以包括：光电检测电路301、放大电路302、模数转换电路303和第二处理器304；
其中，光电检测电路301的检测端固定于气室200的第二端，光电检测电路301的输出端与放大电路302的输入端连接，放大电路302的输出端与模数转换电路303的第一端连接，模数转换电路303的第二端与第二 处理器304的输入端连接；
第二处理器304用于根据自模数转换电路303的第二端接收到的电信号计算得到经过气室200后的红外光的第二光强度值，根据第二红外光强度值与红外光源102发射的红外光的第一光强度值的差值计算得到待测气体的二氧化碳浓度值。
红外信号检测电路用于将通过气室200的红外光转换为电信号进行测量，得到光强度值。具体的，通过将红外信号检测电路中的光电检测电路301的检测端固定于气室200的第二端，接收反应过后的检测光和参比光。红外光源102发射的红外光透过气室200中的待测气体、分别透过检测光滤光片和参比光滤光后，待测气体中的二氧化碳吸收波长为4.26μm的红外光，光电检测电路301收到反应后的检测光和参比光，分别检测二者的第二光强度值，与红外光源102发射的第一光强度值进行对比，通过两个误差值计算待测气体的二氧化碳浓度值。
光电检测电路301可以采用光电二极管，将吸收的光信号转换为对应的电信号，由于该电信号较弱，需要通过放大电路302放大电信号，再经过滤波器滤除干扰信号，而后经模数转换电路303转换为数字信号输入第二处理器304。第二处理器304根据预载的算法计算得到待测气体的二氧化碳浓度值。
第一处理器105和第二处理器304均可以采用单片机。此外，第二处理器304还可以用于将计算得到的二氧化碳浓度值进行存储与传输。相应的，本申请实施例提供的红外吸收型二氧化碳浓度检测装置还可以包括与第二处理器304的输出端连接的通信器，该通信器可以采用RS485通信器305。第二处理器304还用于将待测气体的二氧化碳浓度值通过RS485通信器305发送至上位机。
图2为本申请实施例提供的一种电源电路的电路图。
在上述实施例的基础上，为了便于测试，如图1所示，本申请实施例提供的红外吸收型二氧化碳浓度检测装置还包括用于将输入电压转换为红外光源驱动电路101101的所需电压的电源电路400；
电源电路400的输入端连接交流电源，电源电路400的输出端与红外光源驱动电路101101的输入端连接。
在具体实施中，电源模块具体可以包括：变压器、整流电路和滤波电路；
其中，变压器的输入端用于连接交流电源，变压器的输出端与整流电路的输入端连接，整流电路的输出端与滤波电路的输入端连接，滤波电路的输出端与红外光源驱动电路101101的输入端连接。
电源模块作为整个电路的起始，将220V交流电转化成低压的直流电，为红外光源驱动电路101101提供6-25V的直流电压。
在具体实施中，如图2所示，变压器T的第一端连接220V交流电源(220V AC)，变压器T的第二端(A1、A2侧)连接由二极管D1、D2、D3、D4组成的整流电路，整流电路的输出端连接由电容组成的滤波电路，滤波电路的第二端连接红外光源驱动电路101101的输入端。
基于上述各实施例提供的本申请实施例提供的红外吸收型二氧化碳浓度检测装置，一种测量二氧化碳浓度的工作流程如下：
外接的220V交流电接入本申请实施例提供的红外吸收型二氧化碳浓度检测装置中，经过变压器将电网交流电压变成整流电路所需的交流电压，再将其第二端输出电压经过整流电路中的整流二极管变成直流电流，再经滤波电路滤掉单向脉冲电压中干扰电流成分，给红外光源驱动电路101101提供6-25V范围内的直流电压，该直流电压经过红光光源驱动电路中稳压芯片的稳压作用给红光光源提供稳定电压。随着装置持续工作，装置温度升高使得电路中负载发生改变，通过电压检测电路实时监测红外光源102两端的电压，反馈到第一处理器105，第一处理器105控制可调电阻104来实现稳压作用，结合稳压芯片实现双重稳压，保证光源两端电压的稳定性，进而保证红外光源102发光强度的一致，提高传感器的稳定性。稳定的红外光进过固定长度的气室200，波长为4.26μm的红外光被气室200中的二氧化碳吸收，波长为4.2μm的光透过二氧化碳，通过波长为4.26μm的检测光滤光片和4.2μm的参比光滤波片，即可测得检测光和参比光 的第二光强度值。通过光电检测电路301，将检测到的检测光的第二光强度值和参比光的第二光强度值转化成对应的电信号，经过放大电路302的放大作用，将电信号放大，再经滤波电路滤掉干扰信号。经放大、滤波处理的电信号，经过模数转换处理，得到数字信号输入第二处理器304。第二处理器304利用预载的算法，根据红外光源102产生的红外光的第一光强度值，对比检测光的第二光强度值和参比光的第二光强度值，计算得到待测气体中的二氧化碳浓度。第二处理器304对待测气体中的二氧化碳浓度进行存储与传输，通过RS485通信器305将待测气体中的二氧化碳浓度发送至上位机。
以上对本申请所提供的一种红外吸收型二氧化碳浓度检测装置进行了详细介绍。说明书中各个实施例采用递进的方式描述，每个实施例重点说明的都是与其他实施例的不同之处，各个实施例之间相同相似部分互相参见即可。应当指出，对于本技术领域的普通技术人员来说，在不脱离本申请原理的前提下，还可以对本申请进行若干改进和修饰，这些改进和修饰也落入本申请权利要求的保护范围内。
还需要说明的是，在本说明书中，诸如第一和第二等之类的关系术语仅仅用来将一个实体或者操作与另一个实体或操作区分开来，而不一定要求或者暗示这些实体或操作之间存在任何这种实际的关系或者顺序。而且，术语“包括”、“包含”或者其任何其他变体意在涵盖非排他性的包含，从而使得包括一系列要素的过程、方法、物品或者设备不仅包括那些要素，而且还包括没有明确列出的其他要素，或者是还包括为这种过程、方法、物品或者设备所固有的要素。在没有更多限制的情况下，由语句“包括一个……”限定的要素，并不排除在包括所述要素的过程、方法、物品或者设备中还存在另外的相同要素。
Claims (10)
- 一种红外吸收型二氧化碳浓度检测装置，其特征在于，包括：红外光源电路、置有待测气体的气室和红外信号检测电路；其中，所述红外光源电路包括：红外光源驱动电路、红外光源、电压测量电路、可调电阻和第一处理器；所述红外光源驱动电路的输出端与所述红外光源的驱动端连接；所述可调电阻设于所述红外光源所在电路；所述电压测量电路的第一端与所述红外光源连接，所述电压测量电路的第二端与所述第一处理器的输入端连接；所述红外光源驱动电路的控制端与所述第一处理器的第一输出端连接，所述可调电阻的控制端与所述第一处理器的第二输出端连接；所述第一处理器用于根据所述电压测量电路测得的所述红外光源两端的电压调整所述可调电阻的阻值以维持所述红外光源两端电压的稳定；所述气室的第一端固定于所述红外光源的发射端，所述气室的第二端固定于所述红外信号检测电路的检测端，所述气室中设有滤光片。
- 根据权利要求1所述的红外吸收型二氧化碳浓度检测装置，其特征在于，所述可调电阻具体串联于所述红外光源驱动电路的输出端与所述红外光源的驱动端之间。
- 根据权利要求1所述的红外吸收型二氧化碳浓度检测装置，其特征在于，还包括用于将输入电压转换为所述红外光源驱动电路的所需电压的电源电路；所述电源电路的输入端连接交流电源，所述电源电路的输出端与所述红外光源驱动电路的输入端连接。
- 根据权利要求3所述的红外吸收型二氧化碳浓度检测装置，其特征在于，所述电源电路具体包括：变压器、整流电路和滤波电路；其中，所述变压器的输入端用于连接所述交流电源，所述变压器的输出端与所述整流电路的输入端连接，所述整流电路的输出端与所述滤波电路的输入端连接，所述滤波电路的输出端与所述红外光源驱动电路的输入端连接。
- 根据权利要求1所述的红外吸收型二氧化碳浓度检测装置，其特征 在于，所述红外光源驱动电路具体基于稳压芯片搭建而成。
- 根据权利要求1所述的红外吸收型二氧化碳浓度检测装置，其特征在于，所述滤光片具体包括检测光滤光片和参比光滤光片。
- 根据权利要求6所述的红外吸收型二氧化碳浓度检测装置，其特征在于，所述检测光滤光片具体为4.26μm波段的滤光片。
- 根据权利要求6所述的红外吸收型二氧化碳浓度检测装置，其特征在于，所述参比光滤光片具体为4.2μm波段的滤光片。
- 根据权利要求1所述的红外吸收型二氧化碳浓度检测装置，其特征在于，所述红外信号检测电路具体包括：光电检测电路、放大电路、模数转换电路和第二处理器；其中，所述光电检测电路的检测端固定于所述气室的第二端，所述光电检测电路的输出端与所述放大电路的输入端连接，所述放大电路的输出端与所述模数转换电路的第一端连接，所述模数转换电路的第二端与所述第二处理器的输入端连接；所述第二处理器用于根据自所述模数转换电路的第二端接收到的电信号计算得到经过所述气室后的红外光的第二光强度值，根据所述第二红外光强度值与所述红外光源发射的红外光的第一光强度值的差值计算得到所述待测气体的二氧化碳浓度值。
- 根据权利要求9所述的红外吸收型二氧化碳浓度检测装置，其特征在于，还包括与所述第二处理器的输出端连接的RS485通信器；所述第二处理器还用于将所述待测气体的二氧化碳浓度值通过所述RS485通信器发送至上位机。
Applications Claiming Priority (2)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN202011466218.8 | 2020-12-14 | ||
| CN202011466218.8A CN114460029A (zh) | 2020-12-14 | 2020-12-14 | 一种红外吸收型二氧化碳浓度检测装置 |
Publications (1)
| Publication Number | Publication Date |
|---|---|
| WO2022127144A1 true WO2022127144A1 (zh) | 2022-06-23 |
Family
ID=81403845
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| PCT/CN2021/111994 WO2022127144A1 (zh) | 2020-12-14 | 2021-08-11 | 一种红外吸收型二氧化碳浓度检测装置 |
Country Status (2)
| Country | Link |
|---|---|
| CN (1) | CN114460029A (zh) |
| WO (1) | WO2022127144A1 (zh) |
Citations (6)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN102036437A (zh) * | 2009-09-30 | 2011-04-27 | 海洋王照明科技股份有限公司 | 一种led调光电路 |
| JP2012177690A (ja) * | 2011-02-02 | 2012-09-13 | Ngk Spark Plug Co Ltd | 赤外線ガスセンサ |
| CN103674882A (zh) * | 2013-12-24 | 2014-03-26 | 北京航天测控技术有限公司 | 一种非分红外光气体检测系统 |
| CN204102335U (zh) * | 2014-08-25 | 2015-01-14 | 福建省视通光电网络有限公司 | 一种可调式led交通信号灯 |
| CN107490556A (zh) * | 2017-04-19 | 2017-12-19 | 安徽华脉科技发展有限公司 | 一种红外可燃气体浓度检测系统 |
| CN108982396A (zh) * | 2018-05-30 | 2018-12-11 | 南京信息工程大学 | 一种红外co2气体传感器及其标定系统和温湿度补偿方法 |
-
2020
- 2020-12-14 CN CN202011466218.8A patent/CN114460029A/zh active Pending
-
2021
- 2021-08-11 WO PCT/CN2021/111994 patent/WO2022127144A1/zh active Application Filing
Patent Citations (6)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN102036437A (zh) * | 2009-09-30 | 2011-04-27 | 海洋王照明科技股份有限公司 | 一种led调光电路 |
| JP2012177690A (ja) * | 2011-02-02 | 2012-09-13 | Ngk Spark Plug Co Ltd | 赤外線ガスセンサ |
| CN103674882A (zh) * | 2013-12-24 | 2014-03-26 | 北京航天测控技术有限公司 | 一种非分红外光气体检测系统 |
| CN204102335U (zh) * | 2014-08-25 | 2015-01-14 | 福建省视通光电网络有限公司 | 一种可调式led交通信号灯 |
| CN107490556A (zh) * | 2017-04-19 | 2017-12-19 | 安徽华脉科技发展有限公司 | 一种红外可燃气体浓度检测系统 |
| CN108982396A (zh) * | 2018-05-30 | 2018-12-11 | 南京信息工程大学 | 一种红外co2气体传感器及其标定系统和温湿度补偿方法 |
Also Published As
| Publication number | Publication date |
|---|---|
| CN114460029A (zh) | 2022-05-10 |
Similar Documents
| Publication | Publication Date | Title |
|---|---|---|
| CN101149342A (zh) | 激光气体遥测的方法和装置 | |
| US10506765B2 (en) | Intelligent light adjusting system and intelligent light adjusting method in crop growth process | |
| CN104535531A (zh) | 手持激光气体浓度监测仪及其控制方法 | |
| CN102393374A (zh) | 一种红外呼气末co2测量方法及装置 | |
| CN104458636A (zh) | 一种具有温度气压自动补偿的co2气体浓度监测装置及方法 | |
| CN103424768A (zh) | 一种用于探测器系统的增益稳定装置及其控制方法 | |
| CN106525131B (zh) | 道边呼吸带空气质量在线监测系统 | |
| CN102809547A (zh) | 散射增强可调谐二极管激光痕量气体检测装置及检测方法 | |
| CN108444935B (zh) | 一种非分光红外气体传感器的温度补偿方法及补偿装置 | |
| CN109827902A (zh) | 水质检测设备及其水质检测方法、装置 | |
| CN103115877A (zh) | 一种测量不同气体浓度的光学检测系统 | |
| CN104360692A (zh) | 低浓度标准臭氧发生器的反馈控制装置 | |
| CN210221810U (zh) | 一种带恒温控制功能的高灵敏多气体检测系统 | |
| WO2022127144A1 (zh) | 一种红外吸收型二氧化碳浓度检测装置 | |
| CN114166774A (zh) | 基于ndir原理的红外气体测量系统 | |
| CN202256152U (zh) | 一种特定蛋白测量仪 | |
| CN214427275U (zh) | 一种红外吸收型二氧化碳浓度检测装置 | |
| CN210056025U (zh) | 一种主流呼气末二氧化碳检测仪 | |
| CN111537448A (zh) | 一种可调节量程双光源水质cod检测传感器 | |
| CN209858408U (zh) | 水质检测设备 | |
| CN202631420U (zh) | 重金属在线监测仪的光电检测电路 | |
| CN213580647U (zh) | 一种可调节量程双光源水质cod检测传感器 | |
| CN203275343U (zh) | 一种半导体臭氧传感器测量电路 | |
| CN212031291U (zh) | 一种煤质分析仪及其煤质检测电路 | |
| CN107796771A (zh) | 吸收类分析仪器消除外界杂散光干扰的装置及测量方法 |
Legal Events
| Date | Code | Title | Description |
|---|---|---|---|
| 121 | Ep: the epo has been informed by wipo that ep was designated in this application |
Ref document number: 21905077 Country of ref document: EP Kind code of ref document: A1 |
|
| NENP | Non-entry into the national phase |
Ref country code: DE |
|
| 122 | Ep: pct application non-entry in european phase |
Ref document number: 21905077 Country of ref document: EP Kind code of ref document: A1 |