LAUSR

Low‐finesse fiber‐optic Fabry–Perot (F‐P) interferometric sensor has the advantages of high sensitivity, anti‐electromagnetic interference, and compact size, and is one of the most widely used optical fiber sensors. With the development of sensor design and demodulation algorithms, F‐P sensing technique plays an increasingly important role in high‐speed dynamic measurement, such as dynamic temperature or pressure, acoustic vibration, dynamic displacement, and distance. Signal demodulation methods largely determine the performance of the entire sensing system. Compared with quasi‐static measurement, high‐precision measurement of dynamic F‐P cavity is more challenging. The advancement of fast tunable laser technology in telecommunication field provides novel perspectives for demodulation methods and dynamic applications based on F‐P sensors. This article reviews the latest developments in fast interrogation techniques for dynamic low‐finesse F‐P sensors, including intensity demodulation, quadrature phase demodulation and absolute cavity length demodulation. In addition, array multiplexing and multi‐parameter measurement techniques are also involved.