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Wavelength-selective multispectral and hyperspectral imaging systems in the visible and near-infrared (NIR) range have shown immense potential in applications such as remote sensing, biomedical diagnostics, and optical communications. In this thesis, we present a series of advances in narrowband filter design, SPAD-based imaging integration, and metasurface-enabled polarimetric systems. First, we demonstrate a 16-band ultra-narrow hyperspectral imaging system based on a Fabry-Perot (FP) structure, operatin

Context. It is now generally accepted that the near-infrared excess of Herbig AeBe stars originates in the dust of a circumstellar disk. Aims. The aims of this article are to infer the radial and vertical structure of these disks at scales of order 1 au, a ...

The goal of this project is to find a substrate and parameters that allow the realisation of hight aspect ratio microstructures. We tried three substrates (Ti, Cr and Si), two photoresist thicknesses (50 and 100 [m]), two focalisation points (8 and 12 [m]), four laser powers (110, 88, 70 and 66 [mW]). We obtained smaller structures and higher aspect ratios with silicon. The resine thicknesses give us expected results, such as 50 [m] gives smaller structures than 100 [m] but the aspect ratio rules for the re

The relation between the near–field and far–field properties of plasmonic nanostructures that exhibit Fano resonances is investigated in detail. We show that specific features visible in the asymmetric lineshape far–field response of such structures originate from particular polarization distributions in their near–field. In particular we extract the central frequency and width of plasmonic Fano resonances and show that they cannot be directly found from far–field spectra. We also address the effect of the

Introduction Les caméras multispectrales - Caractéristiques (tableau comparatif) Analyse du bruit (entropie) Analyse de la résolution effective (Full Width of edge response at Half Height) Comparaison des résolutions spatiales Formats de compression Rehaussement Interprétation visuelle Applications - Foresterie

In this report, higher order color mechanisms for the detection of spatial distributions of color are investigated. The objective of this work is to understand which are the visual mechanisms involved in chromatic detection tasks and to dene the properties of such mechanisms. Despite great investigation eorts, human color vision is far from being satisfactorily explained. It is still not clear which mechanisms, at a post-receptoral level, mediate color detection. Recently, psychophysical studies have argued

Experiments with high-power electron cyclotron heating (ECH) and current drive (ECCD) in the TCV tokamak are discussed. Power up to 2.7 MW from six gyrotrons is delivered to the tokamak at the second-harmonic frequency (82.7 GHz) in X-mode. The power is transmitted to the plasma by six independent launchers, each equipped with steerable mirrors that allow a wide variety of injection angles in both the poloidal and toroidal directions. Fully non-inductive operation of the tokamak has been achieved in steady

We report the optical properties of high quality V-groove GaAs/Al0.3Ga0.7.As quantum wires (QWRs) with different thicknesses of the GaAs layer. The systematic investigation of photoluminescence (PL) and photoluminescence excitation (PLE) spectra as a function of the wire size combined with model calculations allows us to study in detail the effect of two-dimensional quantum confinement on valence band mixing and polarization anisotropy. We show that the polarization anisotropy of PL spectra critically depen

Among all non-linear optical effects observed in single-mode optical fibres, stimulated Brillouin scattering (SBS) is of particular importance since it has numerous practical implications. SBS occurs when laser waves are scattered through the interaction of light with hypersonic acoustic waves in the medium. It manifests through the generation of a backscattered Stokes wave that carries most of the input optical power once a definite intensity level is reached within the fibre core. It limits the maximum op

We measured at high energy and angular resolution the spectral width of photoemission features near the Fermi energy for Ag(100) and for the nearly-two-dimensional metal 2H-NbSe2. The results do not agree with the quadratic width-energy relationship predicted for the lifetime broadening of a Fermi liquid: We found a nearly inverse linear relationship for the sp band of Ag(100), and a similar behavior in the case of NbSe2. These results indicate that the broadening is primarily affected by extrinsic factors

In a study of heteronuclear J NMR spectroscopy, the radio frequency phase of the initial 90 Deg pulse was shifted together with the phase of the refocusing pulse. In heteronuclear spectra, the phase cycling method shifts all resonances by DF1 = (4Dt-1)-1 corresponding to 1/2 of the spectral width in the F1 frequency domain. Thus the proton transmitter can be set in the middle of the proton spectrum without introducing aliasing problems, and the technique does not interfere with ordinary quadrature detection

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Metasurface-enhanced Multispectral and Polarization Filtering for SPAD imaging sensors

Structure of Herbig AeBe Disks at the milliarcsecond Scale—A Statistical Survey in the H Band Using PIONIER-VLTI

High Aspect Ratio Microstructures

Relation between near–field and far–field properties of plasmonic Fano resonances

Prospection sur les images numériques proche infrarouge

Color Contrast Detection in Spatial Chromatic Noise

High-power ECH and fully non-inductive operation with ECCD in the TCV tokamak

Optical spectroscopy study of carriers recombination in quantum wires

La diffusion Brillouin dans les fibres optiques : étude et application aux capteurs distribués

Photoemission Broadening of Fermi-Liquid Systems, and Its Relevance to High-Temperature Superconductors

Heteronuclear J spectroscopy