THz QCL self-mixing interferometry for biomedical applications

Rakić, Aleksandar D.; Taimre, Thomas; Bertling, Karl; Lim, Yah Leng; Wilson, Stephen J.; Nikolić, M.; Valavanis, Alexander; Indjin, D.; Linfield, E. H.; Davies, A. G.; Ferguson, Blake; Walker, Graeme J.; Schaider, Helmut; Soyer, H. Peter

doi:10.1117/12.2061433

Cited by 6 publications

(6 citation statements)

References 65 publications

Supporting

Mentioning

Contrasting

Order By: Relevance

“…SMI tomography is an imaging technique that can be achieved on any diffusing media, such as the skin, by the use of modulated, frequency-shifted optical feedback in the range of few hundred kilohertz to several megahertz. Different laser sources have been employed, but quantum cascade lasers (QCL) modulated in the range of 1–5 THz have turned out to be ideal to examine structures within the superficial layer of the skin, thus allowing discrimination between healthy and pathological tissue [ 84 ]. The separation between the peaks of the time-domain SMI signal, as well as their phase and shape, are parameters related to the length of the external cavity and the complex reflectivity of the target (the skin), which allows obtaining high-resolution images from tissue grafts or phantoms.…”

Section: Self-mixing Interferometrymentioning

confidence: 99%

Optical Technologies for the Improvement of Skin Cancer Diagnosis: A Review

Rey-Barroso

Peña-Gutiérrez

Yáñez

et al. 2021

Sensors

View full text Add to dashboard Cite

The worldwide incidence of skin cancer has risen rapidly in the last decades, becoming one in three cancers nowadays. Currently, a person has a 4% chance of developing melanoma, the most aggressive form of skin cancer, which causes the greatest number of deaths. In the context of increasing incidence and mortality, skin cancer bears a heavy health and economic burden. Nevertheless, the 5-year survival rate for people with skin cancer significantly improves if the disease is detected and treated early. Accordingly, large research efforts have been devoted to achieve early detection and better understanding of the disease, with the aim of reversing the progressive trend of rising incidence and mortality, especially regarding melanoma. This paper reviews a variety of the optical modalities that have been used in the last years in order to improve non-invasive diagnosis of skin cancer, including confocal microscopy, multispectral imaging, three-dimensional topography, optical coherence tomography, polarimetry, self-mixing interferometry, and machine learning algorithms. The basics of each of these technologies together with the most relevant achievements obtained are described, as well as some of the obstacles still to be resolved and milestones to be met.

show abstract

Section: Self-mixing Interferometrymentioning

confidence: 99%

Optical Technologies for the Improvement of Skin Cancer Diagnosis: A Review

Rey-Barroso

Peña-Gutiérrez

Yáñez

et al. 2021

Sensors

View full text Add to dashboard Cite

show abstract

“…These include the ability to penetrate many visually-opaque materials, the characteristic THz spectral responses of a wide range of organic and inorganic materials, and the non-ionizing nature of THz radiation. The development of reflection-mode, non-invasive and fast THz imaging systems [1,2], in particular, is essential for the realisation of key applications in the realms of biomedical imaging [3][4][5][6][7][8][9][10], security screening [11][12][13][14][15], and non-destructive industrial inspection [16,17].…”

Section: Introductionmentioning

confidence: 99%

Coherent imaging using laser feedback interferometry with pulsed-mode terahertz quantum cascade lasers

Lim¹,

Bertling²,

Taimre³

et al. 2019

Opt. Express

Self Cite

View full text Add to dashboard Cite

We report a coherent terahertz (THz) imaging system that utilises a quantum cascade laser (QCL) operating in pulsed-mode as both the source and detector. The realisation of a short-pulsed THz QCL feedback interferometer permits both high peak powers and improved thermal efficiency, which enables the cryogen-free operation of the system. In this work, we demonstrated pulsed-mode swept-frequency laser feedback interferometry experimentally. Our interferometric detection scheme not only permits the simultaneous creation of both amplitude and phase images, but inherently suppresses unwanted background radiation. We demonstrate that the proposed system utilising microsecond pulses has the potential to achieve 0.25 mega-pixel per second acquisition rates, paving the pathway to video frame rate THz imaging. Published by The Optical Society under the terms of the Creative Commons Attribution 4.0 License. Further distribution of this work must maintain attribution to the author(s) and the published article's title, journal citation, and DOI. Using a THz QCL as an illumination source allows for higher resolution imaging than sub-THz systems (due to the shorter wavelength) and many orders of magnitude more power (> 100 mW) than typical time-domain systems [26]. Therefore, the THz QCL is emerging as an obvious

show abstract

“…This is pushing forward a number of novel approaches to sensors. Applications in THz wavelengths are blooming, including large opportunities in the biomedical field [ 20 ], but also in spectroscopy [ 21 ], material analysis [ 22 ] including the detection of plastic explosives [ 23 ], and imaging, both by scanning [ 24 ] or by using a synthetic aperture approach [ 25 ].…”

Section: Introductionmentioning

confidence: 99%

Current Developments on Optical Feedback Interferometry as an All-Optical Sensor for Biomedical Applications

Perchoux

Quotb

Atashkhooei

et al. 2016

Sensors

View full text Add to dashboard Cite

Optical feedback interferometry (OFI) sensors are experiencing a consistent increase in their applications to biosensing due to their contactless nature, low cost and compactness, features that fit very well with current biophotonics research and market trends. The present paper is a review of the work in progress at UPC-CD6 and LAAS-CNRS related to the application of OFI to different aspects of biosensing, both in vivo and ex vivo. This work is intended to present the variety of opportunities and potential applications related to OFI that are available in the field. The activities presented are divided into two main sensing strategies: The measurement of optical path changes and the monitoring of flows, which correspond to sensing strategies linked to the reconstruction of changes of amplitude from the interferometric signal, and to classical Doppler frequency measurements, respectively. For optical path change measurements, measurements of transient pulses, usual in biosensing, together with the measurement of large displacements applied to designing palliative care instrumentation for Parkinson disease are discussed. Regarding the Doppler-based approach, progress in flow-related signal processing and applications in real-time monitoring of non-steady flows, human blood flow monitoring and OFI pressure myograph sensing will be presented. In all cases, experimental setups are discussed and results presented, showing the versatility of the technique. The described applications show the wide capabilities in biosensing of the OFI sensor, showing it as an enabler of low-cost, all-optical, high accuracy biomedical applications.

show abstract

THz QCL self-mixing interferometry for biomedical applications

Cited by 6 publications

References 65 publications

Optical Technologies for the Improvement of Skin Cancer Diagnosis: A Review

Optical Technologies for the Improvement of Skin Cancer Diagnosis: A Review

Coherent imaging using laser feedback interferometry with pulsed-mode terahertz quantum cascade lasers

Current Developments on Optical Feedback Interferometry as an All-Optical Sensor for Biomedical Applications

Contact Info

Product

Resources

About