Numerical study using finite element method for the thermal response of fiber specklegram sensors with changes in the length of the sensing zone

• Published in: Kompʹûternaâ optika Vol. 45; no. 4; pp. 534 - 540
• Main Authors: Arango, J.D., Vélez, Y.A., Aristizabal, V.H., Vélez, F.J., Gómez, J.A., Quijano, J.C., Herrera-Ramirez, J.
• Format: Journal Article
• Language: English
• Published: Samara National Research University 01.07.2021
• Subjects: computational electromagnetic methods; fiber optics sensors; numerical approximation and analysis; optical sensing and sensors; speckle interferometry
• ISSN: 0134-2452; 2412-6179
• DOI: 10.18287/2412-6179-CO-852

The response of fiber specklegram sensors (FSSs) is given as function of variations in the intensity distribution of the modal interference pattern or speckle pattern induced by external disturbances. In the present work, the behavior of a FSS sensing scheme under thermal perturbations is studied by means of computational simulations of the speckle patterns. These simulations are generated by applying the finite element method (FEM) to the modal interference in optical fibers as a function of the thermal disturbance and the length of the sensing zone. A correlation analysis is performed on the images generated in the simulations to evaluate the dependence between the changes in the speckle pattern grains and the intensity of the applied disturbance. The numerical simulation shows how the building characteristic of the length of sensing zone, combined with image processing, can be manipulated to control the metrological performance of the sensors.