How to Use Fiber Optic Sensors for Accurate Absolute Measurements - INVITED Orlando Frazão, Paulo Robalinho, António Vaz, Liliana Soares, Beatriz Soares, Catarina Monteiro, Susana Novais and Susana Silva EPJ Web Conf., 287 (2023) 09008 Published online: 18 October 2023 DOI: 10.1051/epjconf/202328709008