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Author Spotlight: Fabrication of a Low-Cost, Fiber-Coupled, and Air-Spaced Fabry-Pérot Etalon
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Intensity Modulated Photothermal Measurements of NO2 with a Compact Fiber-Coupled Fabry-Pérot Interferometer
Philipp Breitegger1, Benjamin Lang2, Alexander Bergmann2
1Institute of Electronic Sensor Systems, Graz University of Technology, Graz 8010, Austria. p.breitegger@tugraz.at.
Sensors (Basel, Switzerland)
|August 2, 2019
Summary
This study introduces a new photothermal spectroscopy sensor for accurately measuring nitrogen dioxide (NO2) at low levels. The compact design offers fast response times and minimal sensitivity to vibrations, crucial for environmental monitoring.
Area of Science:
- Environmental Science
- Analytical Chemistry
- Optical Engineering
Background:
- Nitrogen dioxide (NO2) is a harmful air pollutant with significant adverse health effects.
- Reliable and sensitive measurement techniques for NO2 are essential for environmental monitoring and public health.
- Existing methods may face limitations in terms of sensitivity, response time, or size.
Purpose of the Study:
- To develop and demonstrate a novel sensor for precise measurement of nitrogen dioxide (NO2) concentrations.
- To utilize photothermal spectroscopy for detecting NO2 at parts per billion (ppb) levels.
- To assess the sensor's performance regarding response time and sensitivity to mechanical vibrations.
Main Methods:
- Employing photothermal spectroscopy to detect absorption-induced temperature changes.
- Utilizing a fiber-coupled Fabry-Pérot interferometer for sensitive temperature detection.
- Measuring NO2 concentrations at ppb levels and evaluating sensor response times.
Main Results:
- Achieved a normalized noise equivalent absorption of 7.5 × 10-8 cm-1W/Hz.
- Demonstrated fast response times down to 3 seconds.
- Showcased minor sensitivity to mechanical vibrations due to the interferometer's rigid structure.
Conclusions:
- The developed photothermal spectroscopy sensor enables reliable NO2 measurement at ppb levels.
- The compact Fabry-Pérot interferometer design facilitates miniaturized sensing concepts and rapid detection.
- This technology holds promise for advanced environmental monitoring applications requiring high sensitivity and speed.
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