Terahertz Geodesic Luneburg Lens Antenna

Terahertz Luneberg Lens

Pushing Sub-THz Frontiers: Our Fully-Metallic Geodesic Luneburg Lens Antenna Why Sub-THz Luneberg lens Matters Classical Luneburg lenses have too much losses above 80 GHz. Together and colleagues at KTH Stockholm, ESA Noordwijk and IETR Rennes, we decided to tackle those issues head-on with a radically different solution—one that would rely on purely metallic wave-guiding optics … Read more

Skeletonization and 3D rendering with real time terahertz tomography

In this collaborative article between Lytid, IMS and Noctylio, we explore the application of terahertzTerahertz radiation is electromagnetic energy commonly associated with frequencies around 0.1 to 10 THz, between microwaves and infrared, where many materials reveal distinctive propagation, absorption, and imaging behavior. More (THz) technology in tomography to create 3D reconstructions in real time. The … Read more

Feasibility of Using a 300 GHz Radar to Detect Fractures and Lithological Changes in Rocks

FMCW radar rock non destructive testing

This article examines the possibility of using a high frequency radar (300 GHz) to detect fractures and lithological changes in rocks. This study, carried out in collaboration between Federico Sanjuan (University of Pau, France) and the IMS laboratory (University of Bordeaux), is in the context of the improvement of the methods of detection and quantification … Read more

Terahertz diffractive imaging with saturated data inpainting

This article focuses on improving diffraction imaging techniques in the field of Térahertz frequencies, by approaching the problem of data saturation due to the limited dynamic range of detection systems. We introduce with the ITMO team (Nikolay V Petrov Team) a new approach to algorithmic reconstruction which deals with saturated areas in the measured intensity … Read more

HOBIT-a New Concept for Pedagogical Innovations in Learning and Teaching Optics

Presentations of the latest HOBIT developments Martin Hachet (INRIA) presented in Jul 2021 the last HOBIT developments at the 13th annual International Conference on Education and New Learning Technologies in Spain (Virtual). You can watch the recorded presentation from the HAL open archive. More details about this publication https://hal.inria.fr/hal-03251807/ Hachet, M., Canioni, L., Guillet, J. … Read more

Varnish Ageing characterization with terahertz waves

This paper focuses on the analysis of time-domain data regarding the measurements conducted on a French Renaissance painting realized on a metal substrate (copper). We specifically focus on the dielectric characterization of the varnish layer and its ageing consequences on THz images. Principal investigators are Quentin Cassar and Corinna Koch Dandolo. The painting The oil … Read more

Guided Reflectometry Imaging Unit using Millimeter Wave FMCW Radars

Plastic wavguide for terahertz sensing in reflection

In this paper published in july 2020 in IEEE Transactions on TerahertzTerahertz radiation is electromagnetic energy commonly associated with frequencies around 0.1 to 10 THz, between microwaves and infrared, where many materials reveal distinctive propagation, absorption, and imaging behavior. More Science and Technology, we present a reflectometry sensing system associated with a frequency modulated continuous … Read more

Terahertz Phase Retrieval Imaging in Reflection

Terahertz holography in relfection

Collaboration with ITMO University about Terahertz After the visit of the great museum of optics in ITMO, Saint Petersbourg, Russia, an interesting discussion started with ITMO colleagues about terahertzTerahertz radiation is electromagnetic energy commonly associated with frequencies around 0.1 to 10 THz, between microwaves and infrared, where many materials reveal distinctive propagation, absorption, and imaging … Read more

Guided terahertz pulse reflectometry with double photoconductive antenna

Guided Terahertz reflectometry setup

This article presents a terahertzTerahertz radiation is electromagnetic energy commonly associated with frequencies around 0.1 to 10 THz, between microwaves and infrared, where many materials reveal distinctive propagation, absorption, and imaging behavior. More imaging system using a waveguide with a reflection topology. The system is based on a femtosecond pulse laser, a transceiver, and a … Read more

NearSense – Advances Towards a Silicon-Based Terahertz Near-Field Imaging Sensor for Ex Vivo Breast Tumour Identification

This paper present the terahertzTerahertz radiation is electromagnetic energy commonly associated with frequencies around 0.1 to 10 THz, between microwaves and infrared, where many materials reveal distinctive propagation, absorption, and imaging behavior. More near field resonator developed in the framework of Nearsense project and pulse time domain images used to determine the best frequency and … Read more

A Solid-State 0.56 THz Near-Field Array for μM-Scale Surface Imaging

We This paper presents a fully-integrated 0.56 THz 128-pixel near-field 1-D sensor array with 10-12 μm lateral resolution. The sensing elements are based two parallel cross-bridged split-ring resonators that utilize a 3-D topology to exhibit high field confinement in the sensing spot. The sensor comprises a scalable excitation scheme that is designed to maximize the … Read more

Study of blood plasma optical properties in mice grafted with Ehrlich carcinoma in the frequency range 0.1 – 1.0 THz

In the course of in vitro studies of blood of laboratory animals with progressing Ehrlich carcinoma, we have revealed the change of the blood plasma optical properties in the THz range, which can be used for developing the express diagnostics of the presence of oncological diseases. An applied software package is elaborated that allows the … Read more

Terahertz biophotonics as a tool for studies of dielectric and spectral properties of biological tissues and liquids

In this review, we describe dielectric properties of biological tissues and liquids in the context of terahertzTerahertz radiation is electromagnetic energy commonly associated with frequencies around 0.1 to 10 THz, between microwaves and infrared, where many materials reveal distinctive propagation, absorption, and imaging behavior. More (THz) biophotonics. We discuss a model of the THz dielectric permittivity of water and … Read more

Terahertz frequency modulated continuous wave imaging advanced data processing for art painting analysis

In this paper, we focus on data processing applied to terahertzTerahertz radiation is electromagnetic energy commonly associated with frequencies around 0.1 to 10 THz, between microwaves and infrared, where many materials reveal distinctive propagation, absorption, and imaging behavior. More FMCW measurement of a painting. Investigated paintings FMCW radar processing The proposed approach consist to use … Read more

Terahertz Spectroscopy and Quantum Mechanical Simulations of Crystalline Copper-Containing Historical Pigments

TerahertzTerahertz radiation is electromagnetic energy commonly associated with frequencies around 0.1 to 10 THz, between microwaves and infrared, where many materials reveal distinctive propagation, absorption, and imaging behavior. More spectroscopy is a non-destructive analytical technique used in artTerahertz technology offers a powerful, non-invasive way to explore and preserve works of art and cultural heritage objects. … Read more

Processing sequence for non-destructive inspection based on 3D terahertz images

In this paper, a processing sequence has been developed to achieve automated analysis and measurements from 3D terahertz acquisitions. This sequence first performs a tomographic reconstruction from a 3D acquisition made by a continuous millimetre wave system. This reconstruction is based on the Ordered Subsets Convex (OSC) algorithm and has been optimized for 3D THz tomography. Optimisations consist of i) including the Gaussian beam model in the computation of expected measured intensity, ii) modelling the blank scan and dark-field from measurements and, iii) taking account for these models in the algorithm. The new method, called THz-OSC, outperforms both the BFP and THz-SART reconstructions.

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Continuous‐wave scanning terahertz near‐field microscope

This paper presents a CW terahertz near-field reflectometry setup using metal wires waveguide. This setup, developped at Montpellier University, is working at 100 GHz.

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Terahertz imaging and tomography as efficient instruments for testing polymer additive manufacturing objects

This paper presents terahertz non destructive test of 3D printed materials in the framework of MetAMMI project.

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Ordered subsets convex algorithm for 3D terahertz transmission tomography

Ordered Subsets Convex (OSC) implementation for terahertz waves and comparison of the quality and the accuracy with other tomographic reconstructions.

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Terahertz radiation for tomographic inspection

This paper demonstrate how it is possible to take into account the physical properties of THz waves used in THz CT scan imaging as an improved beam propagation model. This more realistic model is clearly justified by the fact that previous models were simply relying on well-known and commonly applied X-ray reconstruction methods, which assume a ray tracing approach, whereas the THz beam profile is very far from this hypothesis. The model is introduced in several inversion methods as a convolution filter to perform efficient tomographic reconstructions of acquired objects.

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Advanced Processing Sequence for 3-D THz Imaging

Balacey, H., Recur, B., Perraud, J. B., Sleiman, J. B., Guillet, J. P., & Mounaix, P. (2016). Advanced Processing Sequence for 3-D THz Imaging. IEEE Transactions on Terahertz Science and Technology6(2), 191-198.

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Near-field wire-based passive probe antenna for the selective detection of the longitudinal electric field at terahertz frequencies

Adam, R., Chusseau, L., Grosjean, T., Penarier, A., Guillet, J. P., & Charraut, D. (2009). Near-field wire-based passive probe antenna for the selective detection of the longitudinal electric field at terahertz frequencies. Journal of Applied Physics106(7), 073107.

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Aeronautics composite material inspection with a terahertz time-domain spectroscopy system

Ospald, F., Zouaghi, W., Beigang, R., Matheis, C., Jonuscheit, J., Recur, B., … & González, L. V. (2014). Aeronautics composite material inspection with a terahertz time-domain spectroscopy system. Optical Engineering53(3), 031208-031208.

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Ultra-flexible multiband terahertz metamaterial absorber for conformal geometry applications

Yahiaoui, R., Guillet, J. P., de Miollis, F., & Mounaix, P. (2013). Ultra-flexible multiband terahertz metamaterial absorber for conformal geometry applications. Optics letters38(23), 4988-4990.

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Review of terahertz tomography techniques

Guillet, J. P., Recur, B., Frederique, L., Bousquet, B., Canioni, L., Manek-Hönninger, I., … & Mounaix, P. (2014). Review of terahertz tomography techniques. Journal of Infrared, Millimeter, and Terahertz Waves, 35(4), 382-411.

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Art Painting Diagnostic Before Restoration with Terahertz and Millimeter Waves

Introduction TerahertzTerahertz radiation is electromagnetic energy commonly associated with frequencies around 0.1 to 10 THz, between microwaves and infrared, where many materials reveal distinctive propagation, absorption, and imaging behavior. More time domain imaging, FMCW and spectroscopy are useful tools for artTerahertz technology offers a powerful, non-invasive way to explore and preserve works of art and … Read more

Coupling and propagation of Sommerfeld waves at 100 and 300 GHz

The coupling between a linearly-polarized gaussian beam and a Sommerfeld wave propagating on a circular metallic wire is obtained owing to a differential phase element inserted in front of the metal wire. At millimeter-wavelengths we calculate a theoretical maximum coupling efficiency of 32% for this system in spite of the metal nature and radius in … Read more