Diffuse terahertz spectroscopy in turbid media using a wavelet-based bimodality spectral analysis

Abstract Current terahertz (THz) spectroscopy techniques only use the coherent light beam for spectral imaging. In the presence of electromagnetic scattering, however, the scattering-mitigated incoherent beams allow for flexible emitter-detector geometries, which enable applications such as seeing t...

Descripción completa

Guardado en:

Detalles Bibliográficos
Autores principales:	Mahmoud E. Khani, Omar B. Osman, M. Hassan Arbab
Formato:	article
Lenguaje:	EN
Publicado:	Nature Portfolio 2021
Materias:	Medicine R Science Q
Acceso en línea:	https://doaj.org/article/ff9b439960094070bc7b0b3492c73b7f
Etiquetas:	Agregar Etiqueta Sin Etiquetas, Sea el primero en etiquetar este registro!

id	oai:doaj.org-article:ff9b439960094070bc7b0b3492c73b7f
record_format	dspace
spelling	oai:doaj.org-article:ff9b439960094070bc7b0b3492c73b7f2021-11-28T12:17:57ZDiffuse terahertz spectroscopy in turbid media using a wavelet-based bimodality spectral analysis10.1038/s41598-021-02068-72045-2322https://doaj.org/article/ff9b439960094070bc7b0b3492c73b7f2021-11-01T00:00:00Zhttps://doi.org/10.1038/s41598-021-02068-7https://doaj.org/toc/2045-2322Abstract Current terahertz (THz) spectroscopy techniques only use the coherent light beam for spectral imaging. In the presence of electromagnetic scattering, however, the scattering-mitigated incoherent beams allow for flexible emitter-detector geometries, which enable applications such as seeing through turbid media. Despite this potential, THz spectroscopy using diffuse waves has not been demonstrated. The main obstacles are the very poor signal to noise ratios of the diffused fields and the resonance-like spectral artifacts due to multiple Mie scattering events that obscure the material absorption signatures. In this work, we demonstrate diffuse THz spectroscopy of a heterogeneous sample through turbid media using a novel technique based on the wavelet multiresolution analysis and the bimodality coefficient spectrum, which we define here for the first time using the skewness and kurtosis of the spectral images. The proposed method yields broadband and simultaneous material characterization at detection angles as high as 90° with respect to the incident beam. We determined the accuracy of the wavelet-based diffuse spectroscopy at oblique detection angles, by evaluating the area under the receiver operating characteristic curves, to be higher than 95%. This technique is agnostic to any a priori information on the spectral signatures of the sample materials or the characteristics of the scattering medium, and can be expanded for other broadband spectroscopic modalities.Mahmoud E. KhaniOmar B. OsmanM. Hassan ArbabNature PortfolioarticleMedicineRScienceQENScientific Reports, Vol 11, Iss 1, Pp 1-13 (2021)
institution	DOAJ
collection	DOAJ
language	EN
topic	Medicine R Science Q
spellingShingle	Medicine R Science Q Mahmoud E. Khani Omar B. Osman M. Hassan Arbab Diffuse terahertz spectroscopy in turbid media using a wavelet-based bimodality spectral analysis
description	Abstract Current terahertz (THz) spectroscopy techniques only use the coherent light beam for spectral imaging. In the presence of electromagnetic scattering, however, the scattering-mitigated incoherent beams allow for flexible emitter-detector geometries, which enable applications such as seeing through turbid media. Despite this potential, THz spectroscopy using diffuse waves has not been demonstrated. The main obstacles are the very poor signal to noise ratios of the diffused fields and the resonance-like spectral artifacts due to multiple Mie scattering events that obscure the material absorption signatures. In this work, we demonstrate diffuse THz spectroscopy of a heterogeneous sample through turbid media using a novel technique based on the wavelet multiresolution analysis and the bimodality coefficient spectrum, which we define here for the first time using the skewness and kurtosis of the spectral images. The proposed method yields broadband and simultaneous material characterization at detection angles as high as 90° with respect to the incident beam. We determined the accuracy of the wavelet-based diffuse spectroscopy at oblique detection angles, by evaluating the area under the receiver operating characteristic curves, to be higher than 95%. This technique is agnostic to any a priori information on the spectral signatures of the sample materials or the characteristics of the scattering medium, and can be expanded for other broadband spectroscopic modalities.
format	article
author	Mahmoud E. Khani Omar B. Osman M. Hassan Arbab
author_facet	Mahmoud E. Khani Omar B. Osman M. Hassan Arbab
author_sort	Mahmoud E. Khani
title	Diffuse terahertz spectroscopy in turbid media using a wavelet-based bimodality spectral analysis
title_short	Diffuse terahertz spectroscopy in turbid media using a wavelet-based bimodality spectral analysis
title_full	Diffuse terahertz spectroscopy in turbid media using a wavelet-based bimodality spectral analysis
title_fullStr	Diffuse terahertz spectroscopy in turbid media using a wavelet-based bimodality spectral analysis
title_full_unstemmed	Diffuse terahertz spectroscopy in turbid media using a wavelet-based bimodality spectral analysis
title_sort	diffuse terahertz spectroscopy in turbid media using a wavelet-based bimodality spectral analysis
publisher	Nature Portfolio
publishDate	2021
url	https://doaj.org/article/ff9b439960094070bc7b0b3492c73b7f
work_keys_str_mv	AT mahmoudekhani diffuseterahertzspectroscopyinturbidmediausingawaveletbasedbimodalityspectralanalysis AT omarbosman diffuseterahertzspectroscopyinturbidmediausingawaveletbasedbimodalityspectralanalysis AT mhassanarbab diffuseterahertzspectroscopyinturbidmediausingawaveletbasedbimodalityspectralanalysis
_version_	1718408117625028608

Diffuse terahertz spectroscopy in turbid media using a wavelet-based bimodality spectral analysis

Ejemplares similares