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Laser Driver and Analysis Circuitry Development for Quartz-Enhanced Photoacoustic Spectroscopy of NO2 for IoT Purpose
- Source :
- Proceedings, Vol 2, Iss 13, p 1062 (2018)
- Publication Year :
- 2018
- Publisher :
- MDPI AG, 2018.
-
Abstract
- The rising effort to track local air pollution measurements require low-cost air quality sensors that provide good accuracy, long-term stability and possibly Internet of Things (IoT) connectivity. To provide such a solution and avoid cost-intensive equipment the development of a low-cost environmental sensor system was started. To measure the pollutant NO2, a quartz-enhanced photoacoustic spectroscopy (QEPAS) setup was established. A pulsed 450 nm laser diode excites NO2 molecules due to its strong absorption at this wavelength and causes a vibrational-translational relaxation, which results in an acoustic wave. The acoustic wave is detected by a quartz tuning fork (QTF) which generates a weak electrical signal proportional to the NO2 concentration. To realize this at low cost, a laser driver and an analysis circuit including a lock-in amplifier and analog-to-digital conversion were developed. We present first results, which proof the functionality of the circuitry compared to a more expensive laboratory setup.
Details
- Language :
- English
- ISSN :
- 25043900
- Volume :
- 2
- Issue :
- 13
- Database :
- Directory of Open Access Journals
- Journal :
- Proceedings
- Publication Type :
- Academic Journal
- Accession number :
- edsdoj.3bee04257d4aa883c2172e5e4ff5a0
- Document Type :
- article
- Full Text :
- https://doi.org/10.3390/proceedings2131062