Fiber-optic sensors based on Vernier effect

Fiber-optic sensors have developed rapidly because of their excellent sensing performances and abilities to detect in remote and harsh environments. However, on some special occasions with high requirements for sensitivity and resolution, the traditional optical fiber sensing mechanism is difficult to meet the detection requirements. Therefore, it is very necessary to explore new sensor sensitization mechanisms. Vernier effect, as a simple and efficient sensitization method, has been extensively researched and applied in fiber-optic sensors in recent years. This review paper firstly presents the working principles and mechanism of the fiber-optic sensors based on the Vernier effect, and then discusses and classifies their common structures. Furthermore, the research progress and applications of such sensors are summarized and discussed. Finally, the further development direction of the fiber-optic sensors based on the Vernier sensitization mechanism is discussed and prospected.