Projects per year
Abstract
The ability to identify the contents of a sealed container, without the need to extract a sample, is desirable in applications ranging from forensics to product quality control. One technique suited to this is inverse spatially offset Raman spectroscopy (ISORS) which illuminates a sample of interest with an annular beam of light and collects Raman scattering from the centre of the ring, thereby retrieving the chemical signature of the contents while suppressing signal from the container. Here we explore in detail the relative benefits of a recently developed variant of ISORS, called focus-matched ISORS. In this variant, the Fourier relationship between the annular beam and a tightly focused Bessel beam is exploited to focus the excitation light inside the sample and to match the focal point of excitation and collection optics to increase the signal from the contents without out compromising the suppression of the container signal. Using a flexible experimental setup which can realise both traditional and focus-matched ISORS, and Monte-Carlo simulations, we elucidate the relative advantages of the two techniques for a range of optical properties of sample and container.
Original language | English |
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Pages (from-to) | 8876-8888 |
Number of pages | 13 |
Journal | Optics Express |
Volume | 30 |
Issue number | 6 |
Early online date | 2 Mar 2022 |
DOIs | |
Publication status | Published - 14 Mar 2022 |
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Dive into the research topics of 'To focus-match or not to focus-match inverse spatially offset Raman spectroscopy: a question of light penetration'. Together they form a unique fingerprint.Projects
- 4 Finished
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H2020-FETOPEN-2018-2020. DynAMic: H2020-FETOPEN-2018-2020. DynAMic
Dholakia, K. (PI)
1/01/20 → 31/12/23
Project: Standard
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M Squared - USTAN Biophotonics Nexus: M Sqaured - St Andrews Biophotonics Nexus
Dholakia, K. (PI)
1/11/17 → 31/10/22
Project: Standard
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Resonant and shaped photonics for under: Resonant and shaped photonics for understanding the physical and biomedical world
Dholakia, K. (PI) & Gather, M. C. (CoI)
1/08/17 → 31/07/22
Project: Standard
Datasets
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Data Underpinning "To focus-match or not to focus-match inverse spatially offset Raman spectroscopy: a question of light penetration"
Shillito, G. (Creator), McMillan, L. T. (Creator), Bruce, G. D. (Creator) & Dholakia, K. (Creator), University of St Andrews, 4 Mar 2022
DOI: 10.17630/6afe39e2-5988-4c87-bf8a-d6228593364c
Dataset
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