A quantum cascade laser-based sensor for ambient air monitoring is presented and five gases, affecting the air quality, can be quantified. The light sources are selected to measure CO, NO, NO2, N2O and SO2. The footprint of the measurement setup is designed to fit in two standard 19" rack (48 cm × 65 cm) with 4 height units (18 cm) whereas one is holding the optical components and the other one contains the electronics and data processing unit. The concentrations of the individual analytes are measured using 2f-Wavelength Modulation Spectroscopy (2f-WMS) and a commercially available multipass gas cell defines the optical path. In addition, CO can also be measured with a dispersion-based technique, which allows one to cover a wider concentration range than 2f-WMS. The performance of this prototype has been evaluated in the lab and detection limits in the range of 1ppbv have been achieved. Finally, the applicability of this prototype for ambient air monitoring is shown in a five-week measurement campaign in cooperation with the Municipal Department for Environmental Protection (MA 22) of Vienna, Austria.

中文翻译：

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基于量子级联激光器的多气体传感器，用于环境空气监测。

提出了一种用于环境空气监测的基于量子级联激光器的传感器，可以对影响空气质量的五种气体进行量化。选择光源以测量CO，NO，NO2，N2O和SO2。该测量装置的占地面积设计为可安装在两个标准的19英寸机架（48厘米×65厘米）中，带有4个高度单位（18厘米），而一个则装有光学组件，另一个则装有电子和数据处理单元。使用2f-波长调制光谱仪（2f-WMS）测量各个分析物的浓度，并通过市售的多程气室确定光路，此外，CO还可通过基于分散的技术进行测量，从而可以覆盖范围比2f-WMS更大。该原型的性能已在实验室中进行了评估，检测极限已达到1ppbv的范围。最后，在与奥地利维也纳市环境保护局（MA 22）合作进行的为期五周的测量活动中，展示了该原型在环境空气监测中的适用性。