Fiber-optic microstructured sensors based on abrupt field patterns: theory, fabrication, and applications

Fiber-optic sensing technology has the advantages of passivity, anti-electromagnetic interference, long-distance measurement, high sensitivity and high accuracy, small size, and adaptability to harsh environments such as high-vacuum, high-pressure, and strong magnetic fields compared with the traditional electrical sensing technology. However, with the increasing application requirements, how to further improve the sensitivity of fiber-optic sensors, extend the detection limit and improve the maintenance-free capability has become one of the core issues of the current research. This paper reviews the principle, preparation, and application of fiber-optic microstructured sensing based on abrupt field type. It specifically outlines the development and applications of micro-nano optical fibers, photonic crystal optical fibers, optical fiber gratings and structured optical fibers, and lists the main preparation methods of two types of micro-nano optical fibers from the basic theory of optical fiber microstructured sensor devices.