Novel FBG femtosecond laser inscription method for improved FPI sensors for medical applications

Sven Poeggel, Dineshbabu Duraibabu, Daniele Tosi, Gabriel Leen, Elfed Lewis, Amedee Lacraz, Michael Hambalis, Charalambos Koutsides, Kyriacos Kalli

Research output: Chapter in Book/Report/Conference proceedingConference contributionpeer-review

8 Citations (Scopus)

Abstract

A novel fibre Bragg grating (FBG) post-inscription technique using a femto second laser (FSL), used to modify an optical fibre pressure sensor (OFPS) based on an extrinsic Fabry Perot Interferometer (EFPI) is presented. The resultant sensor is an optical fibre pressure and temperature sensor (OFPTS), able to measure temperature and pressure simultaneously in precisely the same location within the optical fibre. Hence the temperature measurement can be used to accurately compensate any thermal fluctuations in the pressure measurements, leading to an improved long term stability. The Bragg-wavelength can be tailored to coincide with any part of the Fabry-Perot Interferometer (FPI) spectrum (e.g. define the FBG at a valley of the FPI spectrum). We use a modified femtosecond laser, point-by-point inscription method for precise and controlled placement of the fibre Bragg grating. Our technique can be readily adapted to commercial production methods for optical fibre sensors as it greatly mitigates the alignment problems associated with femtosecond laser inscription of gratings in optical fibres. The sensor presented in this paper is entirely fabricated with quartz glass, which makes it fully bio-compatible and can be used for biomedical application. The sensors achieved a high sensitivity of 1.3 nm kPa resulting in a resolution of ∼ 1mmHg and a temperature sensitivity of ∼ 10.7pm K. After the inscription, the sensors still demonstrated a stability of better than 0:1% in 30min. The small diameter of only 200μm allows biomedical in-vivo application in volume restricted areas (e.g. blood vessels or the brain) for simultaneous temperature and pressure measurements.

Original languageEnglish
Title of host publicationIEEE SENSORS 2014, Proceedings
EditorsFrancisco J. Arregui
PublisherInstitute of Electrical and Electronics Engineers Inc.
Pages25-28
Number of pages4
EditionDecember
ISBN (Electronic)9781479901616
DOIs
Publication statusPublished - 12 Dec 2014
Externally publishedYes
Event13th IEEE SENSORS Conference, SENSORS 2014 - Valencia, Spain
Duration: 2 Nov 20145 Nov 2014

Publication series

NameProceedings of IEEE Sensors
NumberDecember
Volume2014-December
ISSN (Print)1930-0395
ISSN (Electronic)2168-9229

Conference

Conference13th IEEE SENSORS Conference, SENSORS 2014
Country/TerritorySpain
CityValencia
Period2/11/145/11/14

Fingerprint

Dive into the research topics of 'Novel FBG femtosecond laser inscription method for improved FPI sensors for medical applications'. Together they form a unique fingerprint.

Cite this