Este trabalho apresenta a pesquisa e desenvolvimento de algoritmos de pré-processamento digital de imagens para câmeras térmicas não refrigeradas na faixa espectral do infravermelho distante. O estudo de câmeras infravermelhas é uma questão estratégica, uma vez que tem aplicações militares, civis e científicas. Este trabalho define a concepção e implementação de algoritmos de pré-processamento de imagem necessários para obter imagens com baixo ruído e alto contraste, tais como: correção de não-uniformidade, substituição de pixels defeituosos, geração de histograma, aumento de contraste e processamento de saída do pixel, com taxa de 30 quadros por segundo, utilizando detector não-resfriado com matriz de plano focal de 320 x 240 pixels. Neste trabalho todos os algoritmos foram implementados em software para se obter resultados rapidamente e, assim, facilitar a validação dos códigos. Foram gerados resultados de caracterização eletro-óptica do sistema montado com indicação das principais figuras de mérito que norteiam o estudo desta tecnologia, tais como: componentes de ruído tridimensionais, potência equivalente de ruído, responsividade e relação sinal-ruído. Os resultados indicam que os algoritmos de pré-processamento de imagem propostos aumentam a qualidade da imagem a ser exibida, e os resultados das figuras de mérito calculadas sobre o vídeo digital mostram que todas as métricas apresentaram resultados satisfatórios. / This work aims to present the research and development of digital image processing algorithms for uncooled LWIR thermal camera in Brazil. The study of an infrared thermal camera is a strategic issue since that has more and more applications in military, judicature, rescue, industry, hospital and science areas. This work describes the design and implementation of all image-processing algorithms required to obtain high-performance images with low noise and high contrast, such as: functions for non-uniformity correction of sensor deficiencies, dead-pixel replacement algorithms, histogram generation, contrast enhancement methods and output pixel processing with frame rate of 30 frames per second based on 320 x 240 Uncooled Focal Plane Array (UFPA). In this work all algorithms was implemented in software to get results quickly and to facilitate the validation of computer codes. There are some results of electro-optical characterization on the assembled system, indicating the main figures of merit that guide the study of this technology, such as: 3D noise components, noise equivalent power (NEP), signal transfer function (SiTF) and noise equivalent temperature difference (NETD). The results indicate that the proposed imageprocessing algorithms increase the quality of the corrected image, and the test results through the digital video of the infrared camera show that all metrics are in accordance with its nominal value.

Este trabalho apresenta a pesquisa e desenvolvimento de algoritmos de pré-processamento digital de imagens para câmeras térmicas não refrigeradas na faixa espectral do infravermelho distante. O estudo de câmeras infravermelhas é uma questão estratégica, uma vez que tem aplicações militares, civis e científicas. Este trabalho define a concepção e implementação de algoritmos de pré-processamento de imagem necessários para obter imagens com baixo ruído e alto contraste, tais como: correção de não-uniformidade, substituição de pixels defeituosos, geração de histograma, aumento de contraste e processamento de saída do pixel, com taxa de 30 quadros por segundo, utilizando detector não-resfriado com matriz de plano focal de 320 x 240 pixels. Neste trabalho todos os algoritmos foram implementados em software para se obter resultados rapidamente e, assim, facilitar a validação dos códigos. Foram gerados resultados de caracterização eletro-óptica do sistema montado com indicação das principais figuras de mérito que norteiam o estudo desta tecnologia, tais como: componentes de ruído tridimensionais, potência equivalente de ruído, responsividade e relação sinal-ruído. Os resultados indicam que os algoritmos de pré-processamento de imagem propostos aumentam a qualidade da imagem a ser exibida, e os resultados das figuras de mérito calculadas sobre o vídeo digital mostram que todas as métricas apresentaram resultados satisfatórios. / This work aims to present the research and development of digital image processing algorithms for uncooled LWIR thermal camera in Brazil. The study of an infrared thermal camera is a strategic issue since that has more and more applications in military, judicature, rescue, industry, hospital and science areas. This work describes the design and implementation of all image-processing algorithms required to obtain high-performance images with low noise and high contrast, such as: functions for non-uniformity correction of sensor deficiencies, dead-pixel replacement algorithms, histogram generation, contrast enhancement methods and output pixel processing with frame rate of 30 frames per second based on 320 x 240 Uncooled Focal Plane Array (UFPA). In this work all algorithms was implemented in software to get results quickly and to facilitate the validation of computer codes. There are some results of electro-optical characterization on the assembled system, indicating the main figures of merit that guide the study of this technology, such as: 3D noise components, noise equivalent power (NEP), signal transfer function (SiTF) and noise equivalent temperature difference (NETD). The results indicate that the proposed imageprocessing algorithms increase the quality of the corrected image, and the test results through the digital video of the infrared camera show that all metrics are in accordance with its nominal value.

Cette thèse CIFRE adresse le développement de diodes laser, émettant à 975nm, de très forte puissance, rendement à la prise élevé, et stabilisées en longueur d’onde pour pompage de fibres dopées Er/Yb et réalisation de lasers à fibre. La thèse a été développée dans le cadre d’un partenariat étroit entre le Laboratoire IMS, le GIE III-V Lab, principal fondeur français de composants à semiconducteurs III-V pour des applications électroniques et photoniques, et THALES Research & Technology à Palaiseau en région parisienne. Un travail en profondeur de caractérisation et d’analyse a porté sur les aspects thermiques qui contribuent, en particulier,à limiter les niveaux de puissance optique de sortie. Dans ce cadre, nous avons réalisé un ensemble de caractérisations complémentaires au GIE III-V lab et à l’IMS nous permettant d’envisager des solutions correctives d’optimisation technologique portant en particulier sur la profondeur de gravure définissant la largeur de la zone d’émission et la nature du substrat dissipateur. Ces solutions ont été proposées à partir de modélisations physiques mises en oeuvre avec un simulateur dédié, propriété de III-V Lab et de simulations par éléments finis thermiques et thermomécaniques (approche multiphysique) de la structure microassemblée définitive. Ces travaux se sont prolongés par la fabrication et la caractérisation électro-optique et thermique de plusieurs structures verticales : LOC (Large Optical Cavity), SLOC (Super Large OpticalCavity) et AOC (Asymetrical Optical Cavity). Les diodes laser de type LOC et SLOC sont stabilisées en longueur d’onde en intégrant un réseau de Bragg (DFB). Une puissance optique de 8W avec une efficacité de 60% a été obtenue ; ce qui permet de situer ces travaux à l’état de l’art international notamment vis-à-vis de ceux publiés par l’Institut Ferdinand-Braun.L’originalité des travaux menés dans cette thèse nous a permis d’avoir accès à une bourse du Cluster européen « Laserlab » (The Integrated Initiative of European Laser Research Infrastructures), pour conduire des campagnes d’expérimentation à l’Institut Max Born à Berlin dans le groupe du Dr J.W. Tomm. Les travaux ont porté sur la caractérisation thermique de ces diodes laser de forte puissance émettant à 975nm, à double hétérostructure symétrique et asymétrique (SLOC et AOC), en utilisant des techniques complémentaires (microphotoluminescence,photoluminescence résolue en temps, spectroscopie de photocourant et mesures L-I pulsées) et permettant d’évaluer le type de contraintes résiduelles apportées par les étapes de report de la diode Laser ainsi que la cinétique de dégradation catastrophique de type COD. / This PhD addresses the development of high-power laser diodes emitting at 975nm withhigh efficiency and wavelength stabilized using a Bragg grating. This thesis was conducted in the framework of a close partnership between IMS Laboratory, the GIE III-V lab, who is themain French founder of III-V semiconductor devices for electronic and photonic applications,and THALES Research & Technology in Palaiseau. An in-depth characterization and analysiswork has addressed thermal aspects that contribute, in particular, to limit the optical outputpower of a laser diode. In such a context, we have carried out a set of complementary characterizations both at III-V lab and IMS allowing us to provide some corrective solutionsfor technological optimization concerning the etching depth of the grooves that defines the emitting stripe of the laser diode and the nature of the submount acting as a thermocompensator.These solutions have been proposed from optical modelling implemented with a dedicated simulator, property of III-V lab, and thermal and thermomechanical (multiphysics approach) finite element simulations of the overall microassembled structure. All this work has resulted in the fabrication as well as electro-optical and thermal characterizations of three vertical structures namely LOC (Large Optical Cavity), SLOC (Super Large Optical Cavity)and AOC (Asymmetrical Optical Cavity). The LOC and SLOC vertical structures have been processed with a Fabry-Perot cavity and also including a Bragg grating (DFB architecture) while the AOC one was only fabricated with a Fabry-Perot cavity. State-of-the-art results aredemonstrated since in particular an optical power of 8W with an efficiency of 60% has been obtained that can be compared to those recently published by the Ferdinand-Braun Institute.The originality of the work carried out in this PhD has allowed us to receive a grant from the European Laserlab Cluster (The Integrated Initiative of the European Laser Research Infrastructures), to conduct dedicated experiments at the Max-Born Institute (Berlin) in thegroup of Dr. J.W. Tomm. The work aimed to characterize mechanical strain of the laser diode induced by the soldering process. Two vertical structures (SLOC and AOC) were investigated using complementary techniques (microphotoluminescence, time-resolved photoluminescence,photocurrent spectroscopy and pulsed L-I measurements), allowing to quantify the level of residual stress provided by the laser diode mounting process as well as the kinetics of the catastrophic degradation process (COD).

Ce travail porte sur la conception, la fabrication et la caractérisation de lentilles planaires nano-structurées dédiées aux capteurs d’images CMOS dans le proche-infrarouge. L’étude des applications et des systèmes d’imagerie optronique mis en jeu ont mis en évidence l’intérêt de l’utilisation des capteurs d’images CMOS dans la bande 800-1100 nm. Les inconvénients liés au silicium et à la structure du pixel justifient l’intégration de lentilles planaires nano-structurées compatibles avec le procédé de fabrication CMOS : une lentille plasmonique, une lentille diffractive métallique dite de Huygens, une lentille diélectrique dite de phase de Fresnel et une lentille à gradient d’indice effectif. Les simulationsélectromagnétiques 2D d’un pixel CMOS complet avec chaque lentille planaire ont démontré l’intérêt de la lentille métallique dans un pixel à faible facteur de remplissage et de la lentille de phase de Fresnel pour un pixel standard. Les simulations électromagnétiques 3D ont permis la conception de ces deux dernières lentilles pour leur fabrication tandis que la lentille à gradient d’indice effectif, susceptible d’approcher le profil de phase idéal, a montré son potentiel pour les pixels CMOS. La caractérisation électro-optique a mis en évidence la performance expérimentale de la lentille de phase de Fresnel fabriquée en "post-process" au LPN-CNRS et de la lentille de Huygens fabriquée "in-process" en fonderie CMOS. Les nombreuses perspectives de ce travail liés à la fabrication et à la marge de progression des lentilles ont été explorées. / This work deals with the design, fabrication and characterization of nanostructuredplanar lenses dedicated to near infrared detection for CMOS image sensors.Applications and optronic systems involved in near infrared imaging have been investigatedin order to highlight the strong interest of CMOS images sensors for the 800-1100 nmspectral band. Limitations of silicon and pixel structure explain the integration of nanostructuredplanar lenses compatible with CMOS fabrication process : a plasmonic lens, a dielectricphase-Fresnel lens, a metallic Huygens lens and a gradient-index lens. 2D electromagneticsimulations of a CMOS pixel with each planar lens have demonstrated the good performanceof the Huygens lens for low fill factor pixels and the phase-Fresnel lens for standard pixels.3D simulations of these lenses have been performed for their integration and fabrication inCMOS image sensors. The 3D design by numerical simulations of a gradient-index lens hasshown its potential interest for CMOS pixels. The experimental performance of a dielectriclens "post-process" integrated/fabricated at LPN-CNRS and a metallic lens "in-process" by aCMOS foundy have been evaluated by electro-optical characterization. Several perspectivesof this work about lens fabrication and potential for improvement have been explored.

Ces travaux de thèse ont pour objectif de proposer une nouvelle technique de caractérisation électro-optique de barrettes de diodes Laser de puissance (DLPs), au niveau émetteur individuel à partir d'un banc dédié, utilisées pour le pompage optique à 808nm de système LIDAR en environnement spatial et en régime QCW. Après une étude métrologique fine, ils décrivent une méthodologie de sélection d'un indicateur précoce de défaillance potentielle et sa capacité à estimer la fiabilité de DLPs en conditions opérationnelles (> 109 impulsions à 100Hz/200µs). L’analyse de la dégradation des DLPs se base sur l'identification de signatures paramétriques de défaillance mises en lumière après une série de tests accélérés ciblés et relatives à l'évolution de la puissance optique, du spectre optique (λmax) et du degré de polarisation (DOP) de chaque émetteur de la barrette. Nous montrons également la forte complémentarité entre la mesure du DOP par électroluminescence et par photoluminescence et nous proposons une méthodologie de sélection précoce des émetteurs en considérant leur localisation dans le plan (λmax, DOP). Ces études expérimentales, confortées par des simulations thermiques et mécaniques par éléments finis en introduisant un grand nombre de paramètres technologiques, ont permis de quantifier les niveaux de contraintes résiduelles dans les DLPs en fonction de différentes configurations d'assemblage et d'établir un lien avec leur fiabilité intrinsèque. / This thesis work aimed to propose a new methodology for electro-optical characterization ofQCW laser diodes array (LDA) at emitter level by using a dedicated test bench. After detailedmetrological study, a methodology for selecting an early failure indicator and its ability to assess theLDA reliability in operational conditions (> 109 Shots at 100Hz/200μs) has been described. The LDAdegradation analysis were based on identification of parametric failure signatures highlighted after aset of accelerated tests and have been focused on the evolution of optical power, optical spectrum(λmax) and the degree of polarization (DOP) of each emitter on the LDA. We also explain the strongcomplementarity between the measured DOP of photoluminescence and the DOP ofelectroluminescence and a methodology for early selection of emitters have been proposed by takinginto account their location in the plane (λmax, DOP). These experimental studies were comforted bythermal and mechanical finite element simulations, by introducing several technological parameters inorder to quantify levels of induced mechanical stresses in LDA under different assemblyconfigurations and to establish the link with their intrinsic reliability.