title: Liquid-air based Fabry-Pérot cavity on fiber tip sensor.
abstract: This paper presents a Fabry-Perot fiber tip sensor based on an air-liquid filled cavity. The cavity is sealed off by a thin gold coated membrane of parylene C, between 300 and 350 nm, creating a particularly flexible diaphragm. In order to retrieve and track the cavity of interest from other cavities formed within the sensor tip, a signal processing of the feedback signal is performed by inverse fast Fourier transform. The experimental sensor has been manufactured and tested for temperature, giving cavity length sensitivities of 6.1 nm/°C and 9.6 nm/°C for temperature increase and decrease respectively. The external gas pressure response gives a sensitivity of 15 nm/kPa. The fiber sensor has also been adapted for force sensing after silicone embedment and has shown a sensitivity of about 8.7 nm/mN. Finally, the sensor has been tested on insertion into a human temporal bone, proving that it could be an interesting candidate for insertion force monitoring for robotic cochlear implantation.
authors.forename: Miguel
authors.initials: M
authors.lastname: Llera
authors.forename: Thierry
authors.initials: T
authors.lastname: Aellen
authors.forename: Javier
authors.initials: J
authors.lastname: Hervas
authors.forename: Yves
authors.initials: Y
authors.lastname: Salvadé
authors.forename: Pascal
authors.initials: P
authors.lastname: Senn
authors.forename: Sébastien
authors.initials: S
authors.lastname: Le Floch
authors.forename: Herbert
authors.initials: H
authors.lastname: Keppner