Fiber-Coupled Ozone Sensor Based on Tuning Fork-Enhanced Interferometric Photoacoustic Spectroscopy

摘要

In this paper, a completely fiber-coupled ozone sensor based on tuning fork (TF)-enhanced photoacoustic spectroscopy is presented. Crystalline silicon micro-TFs are processed and characterized. Their photoacoustically induced motion is monitored by a compact intensity interferometer. An acoustic microresonator for this new type of TFs is optimized. A frequency-doubled Nd:YAG laser is used as an excitation source. The sensor performance is assessed by calibration measurements. It reaches a detection limit of $S = 2.13 hbox{ppm}pm 0.02$ ppm and a noise-equivalent absorption sensitivity of $D = (1.27 times 10^{-9} pm 1.2 times 10^{-11}) hbox{cm}^{-1} hbox{W(Hz)}^{-1/2}$.