Qiao Shunda, Ma Yufei, Patimisco Pietro, Sampaolo Angelo, He Ying, Lang Ziting, Tittel Frank K, Spagnolo Vincenzo
Opt Lett. 2021 Mar 1;46(5):977-980. doi: 10.1364/OL.418520.
A multi-pass quartz-enhanced photoacoustic spectroscopy (MP-QEPAS)-based trace gas sensor is reported. In MP-QEPAS, a multi-pass laser beam pattern through the prong spacing of a quartz tuning fork (QTF) is obtained by means of two right-angle prisms. A large QTF with the prong length of 17 mm and prong spacing of 0.8 mm was employed to increase the passage of multi-pass time and ease the alignment of the beam reflection pattern through the QTF. This multi-pass configuration allows the laser beam to pass through the QTF prong spacing six times. Water vapor () was chosen as target gas to investigate the performance of the MP-QEPAS sensor. Compared to a conventional QEPAS measurement, the MP-QEPAS technique provided an enhancement of signal level of ∼3.2 times.
报道了一种基于多程石英增强光声光谱（MP-QEPAS）的痕量气体传感器。在MP-QEPAS中，通过两个直角棱镜获得穿过石英音叉（QTF）叉指间距的多程激光束图案。采用叉指长度为17mm、叉指间距为0.8mm的大型QTF，以增加多程时间并便于光束反射图案穿过QTF的对准。这种多程配置使激光束能够六次穿过QTF叉指间距。选择水蒸气（）作为目标气体来研究MP-QEPAS传感器的性能。与传统的QEPAS测量相比，MP-QEPAS技术使信号电平增强了约3.2倍。
