A Miniaturized QEPAS Trace Gas Sensor with a 3D-Printed Acoustic Detection Module
College of Power and Energy Engineering, Harbin Engineering University, Harbin 150001, China
National Key Laboratory of Science and Technology on Tunable Laser, Harbin Institute of Technology, Harbin 150001, China
Department of Electrical and Computer Engineering, Rice University, 6100 Main Street, Houston, TX 77005, USA
Authors to whom correspondence should be addressed.
Sensors 2017, 17(8), 1750; https://doi.org/10.3390/s17081750
Received: 8 July 2017 / Revised: 23 July 2017 / Accepted: 28 July 2017 / Published: 31 July 2017
(This article belongs to the Section Physical Sensors)
A 3D printing technique was introduced to a quartz-enhanced photoacoustic spectroscopy (QEPAS) sensor and is reported for the first time. The acoustic detection module (ADM) was designed and fabricated using the 3D printing technique and the ADM volume was compressed significantly. Furthermore, a small grin lens was used for laser focusing and facilitated the beam adjustment in the 3D-printed ADM. A quartz tuning fork (QTF) with a low resonance frequency of 30.72 kHz was used as the acoustic wave transducer and acetylene (C2H2) was chosen as the analyte. The reported miniaturized QEPAS trace gas sensor is useful in actual sensor applications.