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Optical Fibre Pressure Sensors in Medical Applications.

Poeggel S, Tosi D, Duraibabu D, Leen G, McGrath D, Lewis E - Sensors (Basel) (2015)

Bottom Line: This article is focused on reviewing the current state-of-the-art of optical fibre pressure sensors for medical applications.The small dimensions of optical fibre-based pressure sensors, together with being lightweight and flexible, mean that they are minimally invasive for many medical applications and, thus, particularly suited to in vivo measurement.This paper presents an overview of the recent developments in optical fibre-based pressure measurements with particular reference to these application areas.

View Article: PubMed Central - PubMed

Affiliation: Optical Fibre Sensors Research Centre, University of Limerick, Limerick, Ireland. Sven@Poeggel.eu.

ABSTRACT
This article is focused on reviewing the current state-of-the-art of optical fibre pressure sensors for medical applications. Optical fibres have inherent advantages due to their small size, immunity to electromagnetic interferences and their suitability for remote monitoring and multiplexing. The small dimensions of optical fibre-based pressure sensors, together with being lightweight and flexible, mean that they are minimally invasive for many medical applications and, thus, particularly suited to in vivo measurement. This means that the sensor can be placed directly inside a patient, e.g., for urodynamic and cardiovascular assessment. This paper presents an overview of the recent developments in optical fibre-based pressure measurements with particular reference to these application areas.

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Related in: MedlinePlus

Reflected light in: (a) a low finesse Fabry–Perot interferometer (FPI) sensor and (b) in a FBG sensor.
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f4-sensors-15-17115: Reflected light in: (a) a low finesse Fabry–Perot interferometer (FPI) sensor and (b) in a FBG sensor.

Mentions: The Fabry-Perot interferometer is based on the principle of interferometry [92,95]. The Fabry-Perot (FP) cavity is usually located on the tip of an optical fibre and enclosed by a miniature glass diaphragm [74]. The light from the source is coherent in the vicinity of the sensor and can potentially interfere with itself, e.g., by reflection. For a low finesse interferometer (Figure 4a), approximately 4% of the light intensity is reflected at the end face of the single-mode fibre (SMF). The residual light travels the length (L) to the diaphragm, where upon it is also reflected (e.g., another 4% for a glass diaphragm), travels back the same way and finally penetrates back into the SMF. Since the light from the diaphragm has experienced an additional path length (2L) through the cavity filled with air (refractive index (n0)), it has a phase difference, given by Φ0. The intensity (I) in the spectrum for each wavelength (λ) therefore depends on the distance of the diaphragm (L) to the SMF, shown in Equation (4) [96]. The change of the diaphragm with reference to the pressure (i.e., ΔL(ΔP)), can be calculated in the same way as previously demonstrated in Equation (2).


Optical Fibre Pressure Sensors in Medical Applications.

Poeggel S, Tosi D, Duraibabu D, Leen G, McGrath D, Lewis E - Sensors (Basel) (2015)

Reflected light in: (a) a low finesse Fabry–Perot interferometer (FPI) sensor and (b) in a FBG sensor.
© Copyright Policy
Related In: Results  -  Collection

License
Show All Figures
getmorefigures.php?uid=PMC4541926&req=5

f4-sensors-15-17115: Reflected light in: (a) a low finesse Fabry–Perot interferometer (FPI) sensor and (b) in a FBG sensor.
Mentions: The Fabry-Perot interferometer is based on the principle of interferometry [92,95]. The Fabry-Perot (FP) cavity is usually located on the tip of an optical fibre and enclosed by a miniature glass diaphragm [74]. The light from the source is coherent in the vicinity of the sensor and can potentially interfere with itself, e.g., by reflection. For a low finesse interferometer (Figure 4a), approximately 4% of the light intensity is reflected at the end face of the single-mode fibre (SMF). The residual light travels the length (L) to the diaphragm, where upon it is also reflected (e.g., another 4% for a glass diaphragm), travels back the same way and finally penetrates back into the SMF. Since the light from the diaphragm has experienced an additional path length (2L) through the cavity filled with air (refractive index (n0)), it has a phase difference, given by Φ0. The intensity (I) in the spectrum for each wavelength (λ) therefore depends on the distance of the diaphragm (L) to the SMF, shown in Equation (4) [96]. The change of the diaphragm with reference to the pressure (i.e., ΔL(ΔP)), can be calculated in the same way as previously demonstrated in Equation (2).

Bottom Line: This article is focused on reviewing the current state-of-the-art of optical fibre pressure sensors for medical applications.The small dimensions of optical fibre-based pressure sensors, together with being lightweight and flexible, mean that they are minimally invasive for many medical applications and, thus, particularly suited to in vivo measurement.This paper presents an overview of the recent developments in optical fibre-based pressure measurements with particular reference to these application areas.

View Article: PubMed Central - PubMed

Affiliation: Optical Fibre Sensors Research Centre, University of Limerick, Limerick, Ireland. Sven@Poeggel.eu.

ABSTRACT
This article is focused on reviewing the current state-of-the-art of optical fibre pressure sensors for medical applications. Optical fibres have inherent advantages due to their small size, immunity to electromagnetic interferences and their suitability for remote monitoring and multiplexing. The small dimensions of optical fibre-based pressure sensors, together with being lightweight and flexible, mean that they are minimally invasive for many medical applications and, thus, particularly suited to in vivo measurement. This means that the sensor can be placed directly inside a patient, e.g., for urodynamic and cardiovascular assessment. This paper presents an overview of the recent developments in optical fibre-based pressure measurements with particular reference to these application areas.

Show MeSH
Related in: MedlinePlus