Pan Yufeng, Zhao Jinbiao, Lu Ping, Sima Chaotan, Zhang Wanjin, Fu Lujun, Liu Deming, Zhang Jiangshan, Wu Hongpeng, Dong Lei
Wuhan National Laboratory for Optoelectronics (WNLO) and National Engineering Research Center of Next Generation Internet Access-system, School of Optical and Electronic Information, Huazhong University of Science and Technology, Wuhan 430074, China.
Shenzhen Huazhong University of Science and Technology Research Institute, Shenzhen 518000, China.
Photoacoustics. 2022 Aug 10;27:100389. doi: 10.1016/j.pacs.2022.100389. eCollection 2022 Sep.
All-optical light-induced thermoacoustic spectroscopy (AO-LITS) is reported for the first time for highly sensitive and selective gas sensing, in which a commercial standard quartz tuning fork (QTF) is employed as a photothermal detector. The vibration of the QTF was measured by the highly sensitive fiber-optic Fabry-Pérot (FP) interferometry (FPI) technique, instead of the piezoelectric detection in the conventional LITS. To improve the stability of the sensor system, a compact QTF-based fiber-optic FPI module is fabricated by 3D printing technique and a dual-wavelength demodulation method with the ellipse-fitting differential-cross-multiplication algorithm (DW-EF-DCM) is exploited for the FPI measurement. The all-optical detection scheme has the advantages of remote detection and immunity to electromagnetic interference. A minimum detection limit (MDL) of 422 ppb was achieved for hydrogen sulfide (HS), which was ~ 3 times lower than a conventional electrical LITS sensor system. The AO-LITS can provide a promising approach for remote and non-contact gas sensing in the whole infrared spectral region.
首次报道了全光光致热声光谱法（AO-LITS）用于高灵敏度和选择性气体传感，其中采用商用标准石英音叉（QTF）作为光热探测器。通过高灵敏度光纤法布里-珀罗（FP）干涉测量（FPI）技术测量QTF的振动，而不是传统LITS中的压电检测。为提高传感器系统的稳定性，采用3D打印技术制作了基于QTF的紧凑型光纤FPI模块，并利用椭圆拟合差分交叉乘法算法的双波长解调方法（DW-EF-DCM）进行FPI测量。全光检测方案具有远程检测和抗电磁干扰的优点。对于硫化氢（HS）实现了422 ppb的最低检测限（MDL），比传统的电LITS传感器系统低约3倍。AO-LITS可为整个红外光谱区域的远程和非接触气体传感提供一种有前景的方法。
