Results 1 to 10 of about 3,266 (205)

Laser Swept-Frequency Feedback Interferometry for Three-Dimensional Displacement Measurement

IEEE Photonics Technology Letters
Ruiqian Sun, Qinyu Li, Jie Shan, Wei Xia, Dongmei Guo   +4 more
openaire   +1 more source

Non-destructive 3D terahertz imaging via laser feedback interferometry

Silva, Jorge, Plöschner, Martin, Bertling, Karl, Ghantala, Mukund, Gillespie, Tim, Torniainen, Jari, Herbert, Jeremy, Lim, Yah Leng, Taimre, Thomas, Qi, Xiaoqiong, Donose, Bogdan C., Zhou, Tao, Lui, Hoi-Shun, Indjin, Dragan, Han, Yingjun, Li, Lianhe, Valavanis, Alexander, Linfield, Edmund H., Davies, A. Giles, Dean, Paul, Rakić, Aleksandar D.   +20 more
openaire   +2 more sources

Measurement of the emission spectrum of a semiconductor laser using laser-feedback interferometry [PDF]

Scientific Reports, 2017
The effects of optical feedback (OF) in lasers have been observed since the early days of laser development. While OF can result in undesirable and unpredictable operation in laser systems, it can also cause measurable perturbations to the operating ...
James Keeley, Joshua Freeman, Karl Bertling, Yah Leng Lim, Reshma A. Mohandas, Thomas Taimre, Lianhe H. Li, Dragan Indjin, Aleksandar D. Rakić, Edmund H. Linfield, A. Giles Davies, Paul Dean   +11 more
doaj   +10 more sources

Laser feedback interferometry in multi-mode terahertz quantum cascade lasers [PDF]

Optics Express, 2020
The typical modal characteristics arising during laser feedback interferometry (LFI) in multi-mode terahertz (THz) quantum cascade lasers (QCLs) are investigated in this work. To this end, a set of multi-mode reduced rate equations with gain saturation for a general Fabry-Pérot multi-mode THz QCL under optical feedback is developed.
Xiaoqiong Qi, Gary Agnew, Thomas Taimre   +2 more
exaly   +9 more sources

Detection sensitivity of laser feedback interferometry using a terahertz quantum cascade laser [PDF]

Optics Letters, 2019
We report on the high detection sensitivity of a laser feedback interferometry scheme based on a terahertz frequency quantum cascade laser (QCL). We show that variations on the laser voltage induced by optical feedback to the laser can be resolved with the reinjection of powers as low as ∼-125  dB of the emitted power.
James Keeley, Karl Bertling, Pierluigi Rubino   +2 more
exaly   +10 more sources

Terahertz microscopy using laser feedback interferometry based on a generalised phase-stepping algorithm [PDF]

Scientific Reports
In this paper we report an improved method of coherent sensing through the use of a generalized phase-stepping algorithm to extract magnitude and phase information from interferometric fringes acquired by laser feedback interferometry (LFI). Our approach
Daniel Mohun, Nikollao Sulollari, Mohammed Salih, Lianhe H. Li, John E. Cunningham, Edmund H. Linfield, A. Giles Davies, Paul Dean   +7 more
doaj   +6 more sources

Microparticle discrimination using laser feedback interferometry

Optics Express, 2018
In this work, we present a method to discriminate between different microparticle sizes in mixed flowing media based on laser feedback interferometry, which could ultimately form the basis for a small, low-cost, real-time microembolus detector. We experimentally evaluated the performance of the system using microparticle phantoms, and the system ...
Jeremy Herbert, Karl Bertling, Thomas Taimre   +2 more
exaly   +7 more sources

Terahertz imaging of human skin pathologies using laser feedback interferometry with quantum cascade lasers. [PDF]

Biomed Opt Express, 2023
Early detection of skin pathologies with current clinical diagnostic tools is challenging, particularly when there are no visible colour changes or morphological cues present on the skin. In this study, we present a terahertz (THz) imaging technology based on a narrow band quantum cascade laser (QCL) at 2.8 THz for human skin pathology detection with ...
Qi X, Bertling K, Stark MS, Taimre T, Kao YC, Lim YL, Han S, O'Brien B, Collins A, Walsh M, Torniainen J, Gillespie T, Donose BC, Dean P, Li LH, Linfield EH, Davies AG, Indjin D, Soyer HP, Rakić AD.   +19 more
europepmc   +7 more sources

Terahertz near-field nanoscopy based on detectorless laser feedback interferometry under different feedback regimes [PDF]

APL Photonics, 2021
Near-field imaging techniques, at terahertz frequencies (1–10 THz), conventionally rely on bulky laser sources and detectors. Here, we employ a semiconductor heterostructure laser as a THz source and, simultaneously, as a phase-sensitive detector ...
Eva A. A. Pogna, Carlo Silvestri, Lorenzo L. Columbo, Massimo Brambilla, Gaetano Scamarcio, Miriam S. Vitiello   +5 more
doaj   +5 more sources

Monitoring Water Dynamics in Plants using Laser Feedback Interferometry [PDF]

14th Pacific Rim Conference on Lasers and Electro-Optics (CLEO PR 2020), 2020
In the present work, the drought response in Tiger grass (Thysanolaena latifolia) plants has been investigated by monitoring water status using THz QCL based Laser Feedback Interferometry imaging technique.
Singh, K, Bandyopadhyay, A, Bertling, K, Lim, YL, Gillespie, T, Robinson, A, Indjin, D, Han, Y, Li, L, Linfield, EH, Davies, AG, Dean, P, Rakic, AD, Sengupta, A   +13 more
core   +6 more sources