A near-infrared C2H2/CH4 dual-gas sensor system combining off-axis integrated-cavity output spectroscopy and frequency-division-multiplexing-based wavelength modulation spectroscopy

Zheng, Kaiyuan; Zheng, Chuantao; Yao, Dan; Hu, Lien; Liu, Zidi; Li, Junhao; Zhang, Yu; Wang, Yiding; Tittel, Frank K.

doi:10.1039/c8an02164c

Cited by 31 publications

(12 citation statements)

References 35 publications

Supporting

Mentioning

Contrasting

Order By: Relevance

“…When the averaging time reaches 700 s, increasing the averaging time cannot further improve the detection accuracy. At this time, the wavelength fluctuation noise is the main interference [30][31][32]. By further analysis of the test results we can find that the NH3 concentration detected in the corridor is about 50 ppm•m, which is a little higher than the normal NH3 concentration in air.…”

Section: System Stability and Allan Deviationmentioning

confidence: 83%

See 1 more Smart Citation

A Remote Sensor System Based on TDLAS Technique for Ammonia Leakage Monitoring

Zheng

Zhang

et al. 2021

Sensors

Self Cite

View full text Add to dashboard Cite

The development of an efficient, portable, real-time, and high-precision ammonia (NH3) remote sensor system is of great significance for environmental protection and citizens’ health. We developed a NH3 remote sensor system based on tunable diode laser absorption spectroscopy (TDLAS) technique to measure the NH3 leakage. In order to eliminate the interference of water vapor on NH3 detection, the wavelength-locked wavelength modulation spectroscopy technique was adopted to stabilize the output wavelength of the laser at 6612.7 cm−1, which significantly increased the sampling frequency of the sensor system. To solve the problem in that the light intensity received by the detector keeps changing, the 2f/1f signal processing technique was adopted. The practical application results proved that the 2f/1f signal processing technique had a satisfactory suppression effect on the signal fluctuation caused by distance changing. Using Allan deviation analysis, we determined the stability and limit of detection (LoD). The system could reach a LoD of 16.6 ppm·m at an average time of 2.8 s, and a LoD of 0.5 ppm·m at an optimum averaging time of 778.4 s. Finally, the measurement result of simulated ammonia leakage verified that the ammonia remote sensor system could meet the need for ammonia leakage detection in the industrial production process.

show abstract

Section: System Stability and Allan Deviationmentioning

confidence: 83%

Section: System Stability and Allan Deviationmentioning

confidence: 99%

A Remote Sensor System Based on TDLAS Technique for Ammonia Leakage Monitoring

Zheng

Zhang

et al. 2021

Sensors

Self Cite

View full text Add to dashboard Cite

show abstract

“…Over the past decade, wavelength modulation spectroscopy (WMS) has been used in various applications as a widely accepted high-sensitivity detection technique [1], [2], [3]. It shifts to a high-frequency detection band by fast current modulation, suppressing the interference of 1/f noise.…”

Section: Introductionmentioning

confidence: 99%

Second Harmonic Phase Angle Method Based on WMS for Background-Free Gas Detection

et al. 2021

View full text Add to dashboard Cite

We propose a second harmonic phase angle method (WMS-θ 2f ) based on wavelength modulation spectroscopy for trace gas detection. WMS-θ 2f exhibits the advantages of background-free and immunity to light intensity fluctuations. The detection sensitivity is 1-2 orders of magnitude higher than that of the first harmonic phase angle detection method. Moreover, there is room for further improvement in sensitivity by optimizing the linearity of the light intensity modulation of the laser. We verified the feasibility of the WMS-θ 2f method experimentally and theoretically, respectively.

show abstract

“…Some harmful gases are toxic and flammable, e.g. acetylene (C 2 H 2 ) and methane (CH 4 ) [1][2][3], and they can even cause explosions when the concentration level exceeds the explosion limit. In order to avoid safety accidents, gas detection is particularly important.…”

Section: Introductionmentioning

confidence: 99%

“…The disadvantage of this cell is that the mirror utilization rate is low and the cell volume is too large. In 2019, Zheng et al proposed an acetylene sensor based on off-axis integrated-cavity output spectroscopy (OA-ICOS) [1]. The optical path length is greatly affected by the mirror reflectivity.…”

Section: Introductionmentioning

confidence: 99%

Near-Infrared Tunable Laser Absorption Spectroscopic Acetylene Sensor System Using a Novel Three Mirror-Based, Dense Pattern Gas Cell

Zhong

Wang

et al. 2020

Sensors

Self Cite

View full text Add to dashboard Cite

By contrast with the widely reported traditional two mirror-based Herriott cell, a three mirror-based dense pattern gas cell was proposed, of which the modeling and design were proven to be effective through a comparison between the simulated spot pattern and effective path length and those of the experimental results. A mechanical structure was designed to adjust the position/angle of the three mirrors for aligning the optical path. The experimentally measured reflection number was 60, resulting in an optical path length of ~11 m, which agrees well with the theoretical value of 10.95 m. Combined with a near-infrared laser with a center wavenumber located at an acetylene (C2H2) absorption line of 6521.2 cm−1, a C2H2 sensor system was established to verify the feasibility of the three mirror-based gas cell. Assisted by a data acquisition (DAQ) card, a LabVIEW platform was developed to generate the drive signal of the laser and acquire the second harmonic (2f) signal from the output of the detector. Through Allan variance analysis, the limit of detection (LoD) of the sensor system is 4.36 ppm at an average time of 0.5 s; as the average time exceeds 10 s, the LoD is <1 ppm. The proposed model and design of the three mirror-based gas cell can be used to realize similar gas cells with different absorption path lengths for gas detection based on infrared absorption spectroscopy.

show abstract

A near-infrared C₂H₂/CH₄ dual-gas sensor system combining off-axis integrated-cavity output spectroscopy and frequency-division-multiplexing-based wavelength modulation spectroscopy

Abstract: A near-infrared C2H2/CH4 sensor was demonstrated utilizing a miniaturized high finesse cavity with high sensitivity and remarkable dynamic measurement performance.

Cited by 31 publications

References 35 publications

A Remote Sensor System Based on TDLAS Technique for Ammonia Leakage Monitoring

A Remote Sensor System Based on TDLAS Technique for Ammonia Leakage Monitoring

Second Harmonic Phase Angle Method Based on WMS for Background-Free Gas Detection

Near-Infrared Tunable Laser Absorption Spectroscopic Acetylene Sensor System Using a Novel Three Mirror-Based, Dense Pattern Gas Cell

Contact Info

Product

Resources

About