Share Email Print

Journal of Biomedical Optics

Application of long-period-grating sensors to respiratory plethysmography
Author(s): Thomas D. P. Allsop; Karen Carroll; G. Lloyd; David J. Webb; M. Miller; Ian Bennion
Format Member Price Non-Member Price
PDF $20.00 $25.00

Paper Abstract

A series of in-line curvature sensors on a garment are used to monitor the thoracic and abdominal movements of a human during respiration. These results are used to obtain volumetric tidal changes of the human torso in agreement with a spirometer used simultaneously at the mouth. The curvature sensors are based on long-period gratings (LPGs) written in a progressive three-layered fiber to render the LPGs insensitive to the refractive index external to the fiber. A curvature sensor consists of the fiber long-period grating laid on a carbon fiber ribbon, which is then encapsulated in a low-temperature curing silicone rubber. The sensors have a spectral sensitivity to curvature, dλ/dR from ~7-nm m to ~9-nm m. The interrogation technique is borrowed from derivative spectroscopy and monitors the changes in the transmission spectral profile of the LPG's attenuation band due to curvature. The multiplexing of the sensors is achieved by spectrally matching a series of distributed feedback (DFB) lasers to the LPGs. The versatility of this sensing garment is confirmed by it being used on six other human subjects covering a wide range of body mass indices. Just six fully functional sensors are required to obtain a volumetric error of around 6%.

Paper Details

Date Published: 1 November 2007
PDF: 13 pages
J. Biomed. Opt. 12(6) 064003 doi: 10.1117/1.2821198
Published in: Journal of Biomedical Optics Volume 12, Issue 6
Show Author Affiliations
Thomas D. P. Allsop, Aston Univ. (United Kingdom)
Karen Carroll, Aston Univ. (United Kingdom)
G. Lloyd, Aston Univ. (United Kingdom)
David J. Webb, Aston Univ. (United Kingdom)
M. Miller, Univ. Hospital Birmingham NHS Trust (United Kingdom)
Ian Bennion, Aston Univ. (United Kingdom)

© SPIE. Terms of Use
Back to Top