» Articles » PMID: 36236657

Highly Sensitive Strain Sensor by Utilizing a Tunable Air Reflector and the Vernier Effect

Overview
Journal Sensors (Basel)
Publisher MDPI
Specialty Biotechnology
Date 2022 Oct 14
PMID 36236657
Authors
Affiliations
Soon will be listed here.
Abstract

A highly sensitive strain sensor based on tunable cascaded Fabry-Perot interferometers (FPIs) is proposed and experimentally demonstrated. Cascaded FPIs consist of a sensing FPI and a reference FPI, which effectively generate the Vernier effect (VE). The sensing FPI comprises a hollow core fiber (HCF) segment sandwiched between single-mode fibers (SMFs), and the reference FPI consists of a tunable air reflector, which is constituted by a computer-programable fiber holding block to adjust the desired cavity length. The simulation results predict the dispersion characteristics of modes carried by HCF. The sensor's parameters are designed to correspond to a narrow bandwidth range, i.e., 1530 nm to 1610 nm. The experimental results demonstrate that the proposed sensor exhibits optimum strain sensitivity of 23.9 pm/με, 17.54 pm/με, and 14.11 pm/με cascaded with the reference FPI of 375 μm, 365 μm, and 355 μm in cavity length, which is 13.73, 10.08, and 8.10 times higher than the single sensing FPI with a strain sensitivity of 1.74 pm/με, respectively. The strain sensitivity of the sensor can be further enhanced by extending the source bandwidth. The proposed sensor exhibits ultra-low temperature sensitivity of 0.49 pm/°C for a temperature range of 25 °C to 135 °C, providing good isolation for eliminating temperature-strain cross-talk. The sensor is robust, cost-effective, easy to manufacture, repeatable, and shows a highly linear and stable response for strain sensing. Based on the sensor's performance, it may be a good candidate for high-resolution strain sensing.

References
1.
Liu N, Li Y, Wang Y, Wang H, Liang W, Lu P . Bending insensitive sensors for strain and temperature measurements with Bragg gratings in Bragg fibers. Opt Express. 2011; 19(15):13880-91. DOI: 10.1364/OE.19.013880. View

2.
Ma Z, Cheng S, Kou W, Chen H, Wang W, Zhang X . Sensitivity-Enhanced Extrinsic Fabry-Perot Interferometric Fiber-Optic Microcavity Strain Sensor. Sensors (Basel). 2019; 19(19). PMC: 6806183. DOI: 10.3390/s19194097. View

3.
Nan T, Liu B, Wu Y, Wang J, Mao Y, Zhao L . Ultrasensitive strain sensor based on Vernier- effect improved parallel structured fiber-optic Fabry-Perot interferometer. Opt Express. 2019; 27(12):17239-17250. DOI: 10.1364/OE.27.017239. View

4.
Zou M, Liao C, Chen Y, Gan Z, Liu S, Liu D . Measurement of Interfacial Adhesion Force with a 3D-Printed Fiber-Tip Microforce Sensor. Biosensors (Basel). 2022; 12(8). PMC: 9406145. DOI: 10.3390/bios12080629. View

5.
Chen Y, Luo J, Liu S, Zou M, Lu S, Yang Y . A High-Strength Strain Sensor Based on a Reshaped Micro-Air-Cavity. Sensors (Basel). 2020; 20(16). PMC: 7472625. DOI: 10.3390/s20164530. View