Fiber-optic photoacoustic gas sensing: a review

Abstract

Fiber-optic photoacoustic (PA) sensing has important applications in trace gas detection. The fiber-optic Fabry-Perot acoustic sensor implemented applying a cantilever is a novel and highly sensitive PA detector. Demodulation technologies such as intensity demodulation, optical cross-correlation demodulation and spectral demodulation are the key to improving the performance and engineering applications of fiber-optic PA sensors. For the detection of weak PA signals, the white-light interferometry based lock-in detection method is highlighted. On this basis, the miniature fiber-optic PA sensor with the special characteristics of high sensitivity, intrinsic safety, long-distance measurement, and immunity to electromagnetic interference can be designed by combining the cantilever and PA probe. This review also outlines the application of cantilever-enhanced fiber-optic PA sensing technology in the fields of online analyzing of high-voltage electrical equipment, leakage gas monitoring, coal mine spontaneous combustion monitoring and environmental gas monitoring. Finally, the future trend of fiber-optic PA sensing is presented.

Keywords:

• Trace gas detection
• fiber-optic photoacoustic sensing
• interferometric cantilever
• fiber-optic Fabry-Perot acoustic sensor
• acoustic demodulation

Author contributions

The manuscript is written through contributions of all authors. All authors have given approval to the final version of the manuscript.

Disclosure statement

No potential conflict of interest was reported by the author(s).

Additional information

Funding

The authors would like to acknowledge the financial supports from the National Nature Science Foundation of China [62275040, 61905034], Natural Science Foundation of Liaoning Province [2023-MSBA-025], Dalian High-level Talent Innovation Support Plan (2019RQ010).