A miniature SMS-LPG bending sensor with high sensitivity based on multimode fiber embedded-LPG

A miniature bending sensor is designed using multimode fiber (MMF) and single mode fiber (SMF). Two kinds of optical fibers are periodically spliced and arranged. MMF provides a strong refractive index modulation with a short length, and a significant resonance peak forms in only 5 periods. The final length of the sensor is only 3 mm. The evolution process and spectrum characteristics of the SMS-LPG are demonstrated through a simulation and experiment. The bending sensitivity is 31.47 nm/m(-1) with a bending range of 0-2.44 m(-1). The experiment results reveal that the proposed sensor has an insensitive temperature response (0.0106 nm/degrees C). (C) 2019 Elsevier B.V. All rights reserved.