Complex multidimensional capturing setups such as plenoptic cameras (PC) introduce a trade-off between various system properties. Consequently, established capturing properties, like image resolution, need to be described thoroughly for these systems. Therefore models and metrics that assist exploring and formulating this trade-off are highly beneficial for studying as well as designing of complex capturing systems. This work demonstrates the capability of our previously proposed sampling pattern cube (SPC) model to extract the lateral resolution for plenoptic capturing systems. The SPC carries both ray information as well as focal properties of the capturing system it models. The proposed operator extracts the lateral resolution from the SPC model throughout an arbitrary number of depth planes giving a depth-resolution profile. This operator utilizes focal properties of the capturing system as well as the geometrical distribution of the light containers which are the elements in the SPC model. We have validated the lateral resolution operator for different capturing setups by comparing the results with those from Monte Carlo numerical simulations based on the wave optics model. The lateral resolution predicted by the SPC model agrees with the results from the more complex wave optics model better than both the ray based model and our previously proposed lateral resolution operator. This agreement strengthens the conclusion that the SPC fills the gap between ray-based models and the real system performance, by including the focal information of the system as a model parameter. The SPC is proven a simple yet efficient model for extracting the lateral resolution as a high-level property of complex plenoptic capturing systems.

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In this thesis the lateral resolution limits of the Laser Induced Forward Transfer (LIFT) technique are being investigated. LIFT is a laser direct write process with micron and below resolution and is suitable for modifying, repairing and prototyping micro-devices. Single laser pulses with wavelength of 800 nm and duration of 130 fs from a Ti:Sapphire laser system were focused onto a transparent donor substrate coated with thin film to transfer the thin film material in the form of micro-disks through a small air gap onto an acceptor substrate. In this thesis, donor glass substrate coated with 80nm continuous Cr film and also Cr disks array patterned by photolithography or e-beam lithography were used as targets. The ablation threshold and transfer threshold were determined experimentally and compared to results from two-temperature model (TTM) simulations and reasonably agreement was obtained. For the continuous film target, the size of the LIFT disks depend on the laser fluences and the smallest sizes of around 700 nm were obtained near the transfer threshold. For the pre-patterned disks array targets, initially 1.3m Cr disks were fabricated on the donor substrates by photolithography. Small focused, larger defocused and large top-hat laser beams were used to transfer the pre-patterned Cr disks. The morphology of the transferred material and reliability of transfer were studied. It was found that the large top-hat beam gave the most reliable and high quality transfer results, resulting in mostly intact LIFT disks on the acceptor substrate. To push the resolution limit further, 500nm Cr disks fabricated on the donor substrate by e-beam lithography were used. The successful transfer of these 500 nm Cr disks gives a positive indication that LIFT can potentially be extended further to the nano-scale regime (usually defined as having sub-100 nm resolution).

A novel combination of a full-field X-ray detector and particle-induced X-ray emission (PIXE) as an established analytical method has been assembled and examined at the Helmholtz-Zentrum Dresden-Rossendorf (HZDR). The so-called Colour X-ray Camera (CXC) based on a pn-junction charge-coupled device (pnCCD) is interconnected with a poly-capillary optics (PCO) for the purpose of X-ray imaging. This first combination of PIXE as a lowbackground excitation method and the approach of full-field imaging is likely to close the gap between fast and sensitive investigations of large sample surfaces. The assembly called full-field PIXE (FF-PIXE) is intended for laterally resolved and quantifiable surveys of large geological samples with respect to their trace elemental composition. The PCO comprising hundred thousands of capillaries with inner diameters of about 20 µm is employed in order to map the specimen’s characteristic X-ray response induced by 3 MeV protons provided by a 6 MV tandem-accelerator. The subsequent pnCCD-chip comprising 264×264 pixels is capable of individually detecting X-ray photons in the energy range from 1 to 20 keV on a 12×12 mm² large field of view. The camera’s native lateral resolution could be determined to be 76 µm in the medium energy range, which is basically restricted by the pixel dimensions (48×48 µm²). Extensive experimental tests investigating the concept of sample 'illumination', X-ray transmission through the PCO, and imaging properties of the CXC, yielded substantial insights allowing to judge the new concept of X-ray imaging. While the variability of excitation intensity was proven to be better than 10% and the homogeneous response of the detector was verified, energy-dependent imaging impairments arose from the PCO. In comparative measurements at imaging systems using photons and electrons for excitation, both the full field approach and PIXE as the method of choice could be confirmed to be capable of meeting the initial objectives. In addition, enhancement techniques have been successfully tested to overcome downsides arising from the PCO’s transmission characteristics. Apart from suppressing the hexagonal pattern and a radial unevenness caused by the PCO, the system’s lateral resolving power could be improved towards 63 µm when using the 1:1 optics. The investigations have revealed that, at present, the complex transmission nature of the PCO is a main obstacle in obtaining quantitative results. A number of parameters (e.g. frame readout speed) and dependencies (e.g. lateral resolution vs. elemental sensitivity) have nevertheless been identified and explored the understanding of which will help to move forward 'on the road to metrology'. / Die neuartige Kombination eines Vollfeld-Röntgendetektors und partikelinduzierter Röntgenemission (PIXE: 'Proton-Induced X-ray Emission') als etablierte Analysemethode wurde am Helmholtz-Zentrum Dresden-Rossendorf (HZDR) aufgebaut und erforscht. Die sogenannte Röntgenfarbkamera (CXC: 'Colour X-ray Camera') basiert auf Ladungskopplung mit p-n-Übergängen (pnCCD: 'pn-junction Charge-Coupled Device') und ist zwecks Abbildung mit einer Polykapillaroptik (PCO: 'Poly-Capillary Optics') gekoppelt. Dieser erstmalige gemeinsame Einsatz von PIXE, als Analysemethode mit niedrigem Untergrund, und dem Ansatz der Vollfeldabbildung eignet sich, um die Lücke zwischen schneller und empfindlicher Analyse großer Probenoberflächen zu schließen. Die als full-field PIXE (FF-PIXE) bezeichnete Anlage ist für ortsaufgelöste und quantifizierbare Untersuchungen großer geologischer Proben konzipiert und soll insbesondere deren Spurenelementverteilung analysieren. Die charakteristische Röntgenstrahlung wird mit 3 MeV-Protonen, die von einem 6 MV-Tandembeschleuniger bereit gestellt werden, induziert. Die ortsaufgelöste Abbildung dieser induzierten Strahlung wird mittels hunderttausender Kapillaren (je ca. 20 µm Innendurchmesser) realisiert. Der nachgelagerte aus 264×264 Pixeln bestehende pnCCD-Chip ist in der Lage, Röntgenphotonen im Energiebereich von 1 bis 20 keV aus einem 12×12 mm² großen Sichtfeld einzeln zu erfassen. Im mittleren Energiebereich wurde für die Kamera eine native Ortsauflösung von 76 µm ermittelt, die im Wesentlichen durch die Pixeldimensionen (48×48 µm²) bestimmt ist. Umfangreiche experimentelle Tests, die das Konzept der Probenausleuchtung, der Röntgenübertragung durch die PCO und die Abbildungseigenschaften der CXC untersuchten, führten zu wesentlichen Erkenntnissen, die die Beurteilung des neuen Abbildungskonzepts für Röntgenfluoreszenz ermöglichen. Während die Variabilität der Anregungsintensität nachweislich besser als 10% ist und die homogene Empfindlichkeit des Detektors verifiziert wurde, ergaben sich energieabhängige Beeinträchtigungen der Bildübertragung durch die PCO. Vergleichsmessungen mit bildgebenden Systemen, die Photonen und Elektronen zur Anregung verwenden, konnten bestätigen, dass sowohl der Vollfeldansatz, als auch PIXE als Methode der Wahl zur Erreichung der ursprünglichen Ziele geeignet sind. Darüber hinaus wurden verschiedene Techniken zur Bildverbesserung erfolgreich getestet, die durch die PCO verursachte Abbildungsfehler korrigieren. Abgesehen von der Unterdrückung hexagonaler Muster und der Korrektur radialer Ungleichmäßigkeiten konnte das laterale Auflösungsvermögen des Systems bei Verwendung der 1:1-Optik auf 63 µm verbessert werden. Die Untersuchungen haben ergeben, dass die komplexen Übertragungseigenschaften der PCO derzeit eine der größten Hürden sind, um quantitative Ergebnisse zu erzielen. Dennoch wurde eine Reihe von Parametern (z.B.Auslesegeschwindigkeit) und Abhängigkeiten (z.B. Ortsauflösung vs. Elementempfindlichkeit) identifiziert und untersucht, deren Verständis dazu beitragen wird, auf dem Weg zu quantitativen Ergebnissen, voran zu kommen.

Ce manuscrit de thèse présente l’étude des techniques de super-résolution latérale en nanoscopie optique, qui est une des nouvelles techniques d'imagerie haute résolution, aujourd'hui largement utilisée en biophysique et en imagerie médicale, pour imager et caractériser des nanostructures, tout en conservant les avantages de l'imagerie optique en champ lointain comme un vaste champ, la visualisation et l’analyse en temps réel…Un des défis futurs de la microscopie 3D super-résolue est d’éviter l’utilisation des marqueurs fluorescents. La microscopie interférométrique fait partie des techniques d’imagerie 3D sans marquage permettant la détection de nanostructures. Pour améliorer le pouvoir de détection de ce système optique, un premier protocole de traitement d’images a été développé et implémenté, permettant ainsi de révéler des structures initialement non mesurables. Puis, pour améliorer la résolution latérale du système, une nouvelle technique combinant l’interférométrie et le principe du nano-jet photonique a été développée permettant l’observation d’objets de taille inférieure à la limite de diffraction de l’instrument optique. / This manuscript presents the study of the lateral super-resolution techniques in optical nanoscopy, which is a new high-resolution imaging method now widely used in biophysics and medical imaging, to observe and measure nanostructures, with the advantages of far field optical imaging, such as a large field of view, visualization and analysis in real time…One of the future challenges of 3D super resolution microscopy is to avoid the use of fluorescent markers. Interferometric microscopy is a 3D label-free imaging technique enabling the detection of nanostructures. To improve the detection capability of this optical system, a first version of a protocol composed of image processing methods was developed and implemented, revealing structures initially unmeasurable. Then, to improve the lateral resolution of the system, a new technique combining interferometry and the principle of the photonic nano-jet has been developed, thus allowing the observation of objects of a size smaller than the diffraction limit of the optical instrument.