WO2009019467A1 - Compensation de température pour détection de gaz - Google Patents

Compensation de température pour détection de gaz Download PDF

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Publication number
WO2009019467A1
WO2009019467A1 PCT/GB2008/002661 GB2008002661W WO2009019467A1 WO 2009019467 A1 WO2009019467 A1 WO 2009019467A1 GB 2008002661 W GB2008002661 W GB 2008002661W WO 2009019467 A1 WO2009019467 A1 WO 2009019467A1
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WO
WIPO (PCT)
Prior art keywords
measurement
diode
power
gas
gas concentration
Prior art date
Application number
PCT/GB2008/002661
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English (en)
Inventor
Michael J. Smith
Original Assignee
Gas Sensing Solutions Limited
Priority date (The priority date is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the date listed.)
Filing date
Publication date
Application filed by Gas Sensing Solutions Limited filed Critical Gas Sensing Solutions Limited
Publication of WO2009019467A1 publication Critical patent/WO2009019467A1/fr

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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
    • G01N2201/00—Features of devices classified in G01N21/00
    • G01N2201/06—Illumination; Optics
    • G01N2201/062—LED's
    • G01N2201/0624—Compensating variation in output of LED source
    • G—PHYSICS
    • G01—MEASURING; TESTING
    • G01N—INVESTIGATING OR ANALYSING MATERIALS BY DETERMINING THEIR CHEMICAL OR PHYSICAL PROPERTIES
    • G01N2201/00—Features of devices classified in G01N21/00
    • G01N2201/12—Circuits of general importance; Signal processing
    • G01N2201/121—Correction signals
    • G01N2201/1211—Correction signals for temperature

Definitions

  • the present invention relates to temperature compensation in gas detectors, in particular gas detectors having diodes.
  • Non Dispersive InfraRed (NDIR) gas detectors in which radiation is passed through a gas, a Light Emitting Diode (LED) may be used as the radiation source and a photodiode may be used as the radiation detector.
  • the LED and photodiode are both sensitive to temperature. There is therefore a problem in differentiating a temperature induced change from a gas induced change in the sensor output.
  • a particular problem with LEDs and photodiodes in NDIR detectors is that both devices have series and parallel parasitic resistances which vary with temperature.
  • the band-gap voltage will also vary with temperature.
  • the temperature dependent frequency shift of the detected infrared light with respect to the filter frequency can lead to an offset between the measured signals of the reference and measurement photodiodes. In all it is typical for at least 5 different parameters effecting operating efficiency, light output and spectral shift to be affected by temperature change.
  • multiple diodes on a single common substrate to simplify temperature measurement. Additionally, mounting multiple diodes on a common substrate by direct bonding in a close coupled or separated configuration to a heatsink or copper tracked hybrid circuit arrangement also aids stability and measurement.
  • the relative effect of temperature variation is larger.
  • the temperature sensitivity of LEDs and photodiodes can combine with this increased effect of temperature variation to cause poor accuracy in compact NDIR gas sensors.
  • Temperature compensation methods are known in NDIR detectors. However, poor measurement of temperature can result in incorrect compensation, therefore the accuracy of gas detection is compromised, for example the sensor may not accurately detect the concentration of gas.
  • the precision of temperature measurement required depends on the application, but may be as precise as +/- 0.02 0 C. As the sensitive region of the diode which causes the performance change is within its internal junctions, at the core of the device, it is very difficult to measure to the accuracy required, the temperature of this region with an external measuring system or detector as the temperature varies from the external ambient air and changes in ⁇ s as a result of each driving pulse.
  • a method of temperature compensation for a gas sensor comprising a diode, the method comprising the steps of: measurement of a temperature sensitive characteristic of the diode; measurement of a gas concentration; and compensation of the measurement of the gas concentration using the measured temperature sensitive characteristic of the diode.
  • the step of the measurement of the gas concentration uses the measured diode.
  • the step of the measurement of the gas concentration uses a further diode on the same chip as the measured diode.
  • the step of the measurement of the gas concentration uses a further diode in thermal communication with the measured diode.
  • the temperature sensitive characteristic comprises an electrical characteristic.
  • the electrical characteristic comprises a forward voltage.
  • the diode comprises a radiation emitting diode and the step of measuring the gas concentration comprises the step of driving the radiation emitting diode so as to emit radiation.
  • the step of measurement of the temperature sensitive characteristic comprises supplying a first power to the radiation emitting diode and the step of driving the radiation emitting diode so as to emit radiation comprises the step of supplying a second power to the radiation emitting diode.
  • the second power is larger than the first power.
  • the second power is at least ten times larger than the first power.
  • the step of compensation of the measurement of the gas concentration comprises altering the first power to the radiation emitting diode responsive to the measured temperature sensitive characteristic.
  • the method further comprises the step of measurement of a temperature of the components supplying the first power and the step of compensation of the measurement of the gas concentration further uses the measured temperature of the components supplying the first power.
  • the measured temperature of the components supplying the first power is used to correct the measurement of temperature sensitive characteristic.
  • the method further comprises the step of measurement of a temperature of the components supplying the second power and the step of compensation of the measurement of the gas concentration further comprises using the measured temperature of the components supplying the second power.
  • the measured temperature of the components supplying the second power is used to correct the measurement of the gas concentration.
  • the step of compensation of the measurement of the gas concentration comprises force heating or cooling the radiation emitting diode to a predetermined level responsive to the measured temperature sensitive characteristic.
  • the diode comprises a photodiode and the step of measurement of the gas concentration comprises measurement of a signal from the photodiode so as to detect radiation.
  • the diode comprises a reference photodiode and the step of measurement of the gas concentration comprises measuring a signal from the reference photodiode so as to detect radiation.
  • the step of compensation of the measurement of the gas concentration comprises altering the gain of an amplifier of a signal from the photodiode responsive to the measured temperature sensitive characteristic.
  • the step of measurement of the temperature sensitive characteristic comprises supplying the diode with a predetermined voltage or current.
  • the step of compensation of the measurement of the gas concentration comprises using a look-up table to correct the gas concentration responsive to the measured temperature sensitive characteristic.
  • a gas sensor comprising: a diode; a diode measurement means for measurement of a temperature sensitive characteristic of the diode; a gas measurement means for measurement of a gas concentration; and a compensation means for compensation of the measurement of the gas concentration using the measured temperature sensitive characteristic of the diode.
  • the gas measurement means is operable to use the measured diode for the measurement of the gas concentration.
  • the gas measurement means is operable to use a further diode on the same chip as the measured diode for the measurement of the gas concentration.
  • the gas measurement means is operable to use a further diode in thermal communication with measured diode for the measurement of the gas concentration.
  • the temperature sensitive characteristic comprises an electrical characteristic.
  • the electrical characteristic comprises a forward voltage.
  • the diode comprises a radiation emitting diode and the gas measurement means is operable to drive the radiation emitting diode so as to emit radiation for the measurement of the gas concentration.
  • the diode measurement means is operable to supply a first power to the radiation emitting diode for measurement of the temperature sensitive characteristic of the diode and the gas measurement means is operable to drive the radiation emitting diode so as to emit radiation by supplying a second power to the radiation emitting diode.
  • the second power is larger than the first power.
  • the second power is at least ten times larger than the first power.
  • the compensation means is operable to alter the first drive power to the radiation emitting diode responsive to the measured temperature sensitive characteristic.
  • the gas sensor further comprises a first temperature measurement means for measurement of a temperature of the components supplying the first power and the compensation means is further operable to use the measured temperature of the components supplying the first power for the compensation.
  • the first temperature measurement means is operable to use the measured temperature of the components supplying the first power to correct the measurement of temperature sensitive characteristic.
  • the gas sensor further comprises a second temperature measurement means for measurement of a temperature of the components supplying the second power and the compensation means is further operable to use the measured temperature of the components supplying the second power for the compensation.
  • the second temperature measurement means is operable to use the measured temperature of the components supplying the second power to correct the measurement of the gas concentration.
  • the compensation means is operable to force heat or cool the radiation emitting diode to a predetermined level responsive to the measured temperature sensitive characteristic.
  • the diode comprises a photodiode and the gas measurement means is operable to measure a signal from the photodiode so as to detect radiation.
  • the diode comprises a reference photodiode and the gas measurement means is operable to measure a signal from the reference photodiode so as to detect radiation.
  • the compensation means is operable to alter the gain of an amplifier of a signal from the photodiode responsive to the measured temperature sensitive characteristic.
  • the diode measurement means is operable to supply the diode with a predetermined voltage or current.
  • the compensation means is operable to use a look-up table to correct the gas concentration responsive to the measured temperature sensitive characteristic.
  • Figure 1 illustrates in schematic form an apparatus for temperature measurement in accordance with an embodiment of the present invention.
  • Figures 2 to 4 illustrate in schematic form a circuit for the forward voltage measurement of an LED in accordance with an embodiment of the present invention.
  • Figure 2 illustrates in schematic form the Pulse Wave Modulated to DC level conversion section of the circuit.
  • Figure 3 illustrates in schematic form the main and Vf LED drive section of the circuit.
  • Figure 4 illustrates in schematic form the Vf value amplification section of the circuit.
  • This embodiment of the present invention is a CO 2 NDIR gas sensor.
  • the LED 1 is driven with two 500 ⁇ S pulses of between 1 mA and 5mA.
  • the LED is driven by a constant current driver 2, the current being monitored by a microprocessor.
  • the voltage across the LED is measured via a precision voltage measurement circuit 3.
  • other diode measurement means can be used to measure any temperature sensitive characteristic of the diode, electrical or otherwise.
  • the resulting voltage pulse across the LED is fed into a tuned buffer amplifier which produces two pulses (one positive and one negative) for each pulse into the LED. Both the negative and positive pulses are fed into an A/D converter, the negative pulse being inverted in firmware and added to the positive pulse.
  • Vf forward voltage
  • the Vf measurement may be measured on a diode on the same chip as either the LED or photodiode, or by a diode in thermal communication with either the LED or photodiode.
  • the multiple diodes could be mounted on a TO can or similar package, or in an assembly, which could be constructed using bonded, moulded of cast techniques such that the Vf sensing diode is within the combined thermal mass of the assembly. This still has an advantage of measuring compensating for the temperature of the diode being used for gas concentration measurement.
  • the high power LED pulse train is now triggered resulting in a CO2 measurement being captured by the microprocessor, although other digital or analogue circuits could be used as a gas measurement means.
  • the value of the combined Vf reading is then used in a look-up table by the microprocessor to compensate the CO 2 measurement for the LED temperature. This is done by the microprocessor, although other digital or analogue circuits could be used as a compensation means.
  • Vf may be measured during the CO 2 measurement pulse.
  • a non-constant current source may be used.
  • the voltage may be fixed constant with a measurement of the resulting current being used for compensation.
  • a Pulse Width Modulated square wave of frequency 2 kHz is presented to R70. This is smoothed by C34 to become a DC voltage A, B output to the mail LED drive and Vf LED drive sections respectively, shown in Figure 3.
  • the upper section of Figure 3 is the precision driver for the high power drive to the LED D19.
  • the lower section of Figure 3 relates to the low power Vf measurement.
  • the DC voltage at the output of IC8A is passed through R81 and, in the normal state, is shorted by Q2.
  • a short 4.5 ms active low pulse enables the DC voltage through to the precision current source formed by IC7C and Q5.
  • a square pulse of a set current is driven through the LED D19 and a voltage drop is created across it.
  • This square pulse C is output from the LED drive sections of Figure 3 into the Vf Value Amplification section shown in Figure 4. differentiated by C36 and attenuated by the combination of resistor R83 with resistors R79 and R82.
  • the differentiated pulse is buffered by IC7D, low-pass filtered by R13 and C4 then passed D to the processor for A/D measurement.
  • the processor Since it is the processor that initiates the drive pulse, it is able to coherently oversample the differentiated pulse 1200 times.
  • the resultant number, scaled to a 16 bit integer value gives an accuracy of 12 bits of resolution from the processor's 10 bit A/D system.
  • the Vf measurement is linear over a decade of measurement range.
  • the level of the drive pulse can be adjusted by controlling the PWM value to arrange that the resultant measurement can be scaled for best accuracy.
  • the operation of the LED used is very temperature dependant and accurate measurement of its forward voltage correlates directly with its local temperature. By knowing the Vf and therefore the temperature, we can correct the output value of the system using the measured LED forward voltage.
  • the photodiode is positioned at the start of a high gain (10OdB) amplifier chain.
  • the chain is tuned to a known frequency at which the diode is pulsed.
  • Options for detecting the voltage drop across the photodiode include:
  • the photodiode is driven with a known current from a constant current source and the voltage drop across it is measured.
  • the current source must be well isolated from the photodiode when gas measurements are being taken. This can be achieved using a device such as a FET.
  • the photodiode is driven with a known AC (Alternating Current) signal through a series resistor. This will form a potential divider with a potential across the photodiode varying with temperature.
  • the resulting signal will be amplified by the photodiode amplifier chain, and the resulting signal can be used to derive the temperature.
  • This has the advantage of measuring the temperature response of the entire amplifier chain. As a refinement, this signal can be scaled to suit the amplifier chain by changing its frequency away from the centre of the band-pass frequency of the amplifier chain. This will reduce the gain in the chain, allowing the signal to be scaled to a suitable level.
  • the compensation can be achieved by analogue processing, or by digitising the temperature signal and using a microprocessor to carry out the compensation.
  • the LED is driven from a constant current source with a known current. The voltage across the LED is then measured. Alternatively, the LED is driven from a constant voltage source with a known voltage. The current across the LED is then measured.
  • the performance of the LED and Photodiode are highly dependent on their device temperatures.
  • Using accurate measurement of the forward voltage of the LED gives a very accurate indication of its operating temperature.
  • Unfortunately there is a temperature induced error in the precision current driver that is used to drive 1 milliamp into the LED so that its forward voltage can be measured. This is a very small error but is enough to skew the forward voltage measurement and the gas concentration measurement that is dependent upon its accuracy.
  • the microprocessor on the control board has a temperature sensing thermistor, or first temperature measurement means, connected to it that allows the system to know the temperature of the control board and therefore the temperature of the precision current driver components.
  • control board is ramped between the extremes of its operating temperatures in a thermal chamber while the LED and
  • Photodiode are kept at static room temperature of 20 Degrees Centigrade. While the temperature is being ramped, the control board temperature measurement is recorded along with the LED forward voltage.
  • a lookup table is created that is an error correction for the LED forward voltage cross referenced to control board temperature.
  • the LED forward voltage is measured and the numerical value is corrected by using the control board temperature to reference the correction lookup table held on an on-board ROM.
  • the main precision current driver that drives the LED for CO2 measurement is affected by the control board temperature.
  • the value of the measured CO2 requires correction.
  • the CO 2 measurement is corrected by taking the present value of the control board temperature, using a second temperature measurement means such as a thermistor, and using it to refer to a lookup table of correction factors that have been collected during test.
  • the drive current is typically at least 10 times smaller than the current used to illuminate the LED for measurements. Furthermore, the device is only driven for 32 off 1 millisecond pulses per second. This equates to a 3.2% duty cycle so self heating of the LED is reduced to a minimum. Any heating that is brought about may be corrected for by the procedure detailed above.
  • the raw measurement can be passed through suitable signal conditioning such as filtering or moving average measurements.

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  • Health & Medical Sciences (AREA)
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Abstract

La présente invention concerne un procédé et un capteur de gaz permettant une compensation de la mesure de la concentration en gaz à l'aide d'une caractéristique mesurée sensible à la température. Une DEL (1) est commandée par un dispositif de commande de courant constant (2), le courant étant surveillé par un microprocesseur. La tension à travers la DEL est mesurée par un circuit de mesure de tension de précision (3). Une Vf dérivée (tension directe) est utilisée pour la compensation de température (4). L'agencement peut compenser la température dans le cœur de la diode qui est utilisée pour la mesure de la concentration en gaz. En variante, la mesure de la Vf peut être effectuée sur une diode sur la même puce que la DEL ou la photodiode.
PCT/GB2008/002661 2007-08-06 2008-08-05 Compensation de température pour détection de gaz WO2009019467A1 (fr)

Applications Claiming Priority (2)

Application Number Priority Date Filing Date Title
GB0715266A GB0715266D0 (en) 2007-08-06 2007-08-06 Temperature compensation for gas detection
GB0715266.3 2007-08-06

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Publication Number Publication Date
WO2009019467A1 true WO2009019467A1 (fr) 2009-02-12

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Cited By (12)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
GB2475277A (en) * 2009-11-12 2011-05-18 Bah Holdings Llc Optical absorption gas analyser with temperature sensor
WO2011086394A1 (fr) 2010-01-18 2011-07-21 Gas Sensing Solutions Ltd. Capteur de gaz avec guide de rayonnement
WO2012059743A2 (fr) 2010-11-01 2012-05-10 Gas Sensing Solutions Ltd. Procédés et appareil de réglage de température pour capteurs de gaz à absorption optique et capteurs de gaz à absorption optique ainsi réglés
WO2012059744A1 (fr) 2010-11-01 2012-05-10 Gas Sensing Solutions Ltd. Appareil et procédé pour générer des impulsions de lumière à partir de led dans des capteurs de gaz à absorption optique
WO2012040695A3 (fr) * 2010-09-24 2012-08-23 Laguna Research, Inc. Système de détection à infrarouge non diffuseur et procédé de mesure de gaz
GB2500993A (en) * 2012-04-05 2013-10-09 Draeger Safety Ag & Co Kgaa Temperature corrected optical gas sensor
CN104459057A (zh) * 2014-12-28 2015-03-25 武汉思睿泽科技咨询服务有限公司 一种复合污染气体在线监测装置
CN108741235A (zh) * 2018-08-10 2018-11-06 普维思信（北京）科技有限公司 一种加热不燃烧香烟的烘烤装置及协同烘烤方法
EP3581898A1 (fr) 2018-06-13 2019-12-18 E+E Elektronik Ges.M.B.H. Dispositif électronique, capteur optique de gaz comprenant un tel dispositif électronique et procédé de mesure de courant photoélectrique et de température combinée au moyen d'un tel dispositif électronique
CN112683837A (zh) * 2021-01-26 2021-04-20 杭州麦乐克科技股份有限公司 一种基于红外技术的二氧化碳浓度检测方法
WO2021081553A1 (fr) * 2019-10-22 2021-04-29 Nevada Nanotech Systems Inc. Procédés de fonctionnement et d'étalonnage d'un capteur de gaz, et capteurs de gaz associés
CN114324224A (zh) * 2020-10-09 2022-04-12 旭化成微电子株式会社 信号输出装置和浓度测定系统

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US20060119851A1 (en) * 2002-09-06 2006-06-08 Bounaix Fabrice M S Method and device for detecting gases by absorption spectroscopy
US20060263256A1 (en) * 2005-05-17 2006-11-23 Nitrex Metal Inc. Apparatus and method for controlling atmospheres in heat treating of metals
WO2007080398A1 (fr) * 2006-01-10 2007-07-19 Gas Sensing Solutions Limited Capteur de gaz de differenciation

Patent Citations (4)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US5625189A (en) * 1993-04-16 1997-04-29 Bruce W. McCaul Gas spectroscopy
US20060119851A1 (en) * 2002-09-06 2006-06-08 Bounaix Fabrice M S Method and device for detecting gases by absorption spectroscopy
US20060263256A1 (en) * 2005-05-17 2006-11-23 Nitrex Metal Inc. Apparatus and method for controlling atmospheres in heat treating of metals
WO2007080398A1 (fr) * 2006-01-10 2007-07-19 Gas Sensing Solutions Limited Capteur de gaz de differenciation

Cited By (29)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
GB2475277A (en) * 2009-11-12 2011-05-18 Bah Holdings Llc Optical absorption gas analyser with temperature sensor
GB2475277B (en) * 2009-11-12 2014-05-21 Bah Holdings Llc Optical absorption gas analyser
US8665424B2 (en) 2009-11-12 2014-03-04 Bah Holdings Llc Optical absorption gas analyser
WO2011086394A1 (fr) 2010-01-18 2011-07-21 Gas Sensing Solutions Ltd. Capteur de gaz avec guide de rayonnement
WO2012040695A3 (fr) * 2010-09-24 2012-08-23 Laguna Research, Inc. Système de détection à infrarouge non diffuseur et procédé de mesure de gaz
WO2012059743A3 (fr) * 2010-11-01 2012-06-21 Gas Sensing Solutions Ltd. Procédés et appareil de réglage de température pour capteurs de gaz à absorption optique et capteurs de gaz à absorption optique ainsi réglés
CN103299174A (zh) * 2010-11-01 2013-09-11 气体敏感液有限公司 用于从光学吸收气体传感器中的led生成光脉冲的装置及方法
CN103328954A (zh) * 2010-11-01 2013-09-25 气体敏感液有限公司 用于光学吸收气体传感器的温度校准方法和设备以及由此校准的光学吸收气体传感器
JP2013545094A (ja) * 2010-11-01 2013-12-19 ガス・センシング・ソリューションズ・リミテッド 光吸収ガスセンサ内のｌｅｄから光パルスを生成するための装置と方法
US9410886B2 (en) 2010-11-01 2016-08-09 Gas Sensing Solutions Ltd. Apparatus and method for generating light pulses from LEDs in optical absorption gas sensors
WO2012059744A1 (fr) 2010-11-01 2012-05-10 Gas Sensing Solutions Ltd. Appareil et procédé pour générer des impulsions de lumière à partir de led dans des capteurs de gaz à absorption optique
WO2012059743A2 (fr) 2010-11-01 2012-05-10 Gas Sensing Solutions Ltd. Procédés et appareil de réglage de température pour capteurs de gaz à absorption optique et capteurs de gaz à absorption optique ainsi réglés
US9285306B2 (en) 2010-11-01 2016-03-15 Gas Sensing Solutions Ltd. Temperature calibration methods and apparatus for optical absorption gas sensors, and optical absorption gas sensors thereby calibrated
GB2500993A (en) * 2012-04-05 2013-10-09 Draeger Safety Ag & Co Kgaa Temperature corrected optical gas sensor
DE102012007016B3 (de) * 2012-04-05 2013-10-10 Dräger Safety AG & Co. KGaA Optischer Gassensor
US8649012B2 (en) 2012-04-05 2014-02-11 Dräger Safety AG & Co. KGaA Optical gas sensor
GB2500993B (en) * 2012-04-05 2015-07-08 Draeger Safety Ag & Co Kgaa Optical gas sensor
CN104459057A (zh) * 2014-12-28 2015-03-25 武汉思睿泽科技咨询服务有限公司 一种复合污染气体在线监测装置
EP3581898A1 (fr) 2018-06-13 2019-12-18 E+E Elektronik Ges.M.B.H. Dispositif électronique, capteur optique de gaz comprenant un tel dispositif électronique et procédé de mesure de courant photoélectrique et de température combinée au moyen d'un tel dispositif électronique
DE102019208173A1 (de) 2018-06-13 2019-12-19 E+E Elektronik Ges.M.B.H. Elektronische Anordnung, optischer Gassensor umfassend eine solche elektronische Anordnung und Verfahren zur kombinierten Fotostrom- und Temperaturmessung mittels einer solchen elektronischen Anordnung
CN110595530A (zh) * 2018-06-13 2019-12-20 益加义电子有限公司 电子装置、光学的气体传感器和测量光电流和温度的方法
CN110595530B (zh) * 2018-06-13 2022-02-01 益加义电子有限公司 电子装置、光学的气体传感器和测量光电流和温度的方法
US11262295B2 (en) 2018-06-13 2022-03-01 E+E Elektronik Ges.M.B.H. Electronic arrangement, optical gas sensor including such an electronic arrangement, and method for combined photocurrent and temperature measurement using such an electronic arrangement
CN108741235A (zh) * 2018-08-10 2018-11-06 普维思信（北京）科技有限公司 一种加热不燃烧香烟的烘烤装置及协同烘烤方法
CN108741235B (zh) * 2018-08-10 2023-12-26 普维思信(深圳)科技有限公司 一种加热不燃烧香烟的烘烤装置及协同烘烤方法
WO2021081553A1 (fr) * 2019-10-22 2021-04-29 Nevada Nanotech Systems Inc. Procédés de fonctionnement et d'étalonnage d'un capteur de gaz, et capteurs de gaz associés
CN114324224A (zh) * 2020-10-09 2022-04-12 旭化成微电子株式会社 信号输出装置和浓度测定系统
CN112683837A (zh) * 2021-01-26 2021-04-20 杭州麦乐克科技股份有限公司 一种基于红外技术的二氧化碳浓度检测方法
CN112683837B (zh) * 2021-01-26 2023-07-21 杭州麦乐克科技股份有限公司 一种基于红外技术的二氧化碳浓度检测方法

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