The goal of the research reported in this thesis is to establish the feasibility of a novel optical architecture for an optical route & select circuit switch suitable for implementation as a photonic integrated circuit. The proposed architecture combines Optical Phased Array (OPA) switch elements implemented as multimode interference coupler based Generalised Mach-Zehnder Interferometers (GMZI) with a planar Lüneburg lens-based optical transpose interconnection network implemented using graded metamaterial waveguide slabs. The proposed switch is transparent to signal format and, in principle, can have zero excess insertion loss and scale to large port counts. These switches will enable the low-energy consumption high capacity communications network infrastructure needed to provide environmentally-friendly broadband access to all. The thesis first explains the importance of switch structures in optical communications networks and the difficulties of scaling to a large number of switch ports. The thesis then introduces the Talbot effect, i.e. the self-imaging of periodic field distributions in free space. It elaborates on a new approach to finding the phase relations between pairs of Talbot image planes at carefully selected positions. The free space Talbot effect is mapped to the waveguide Talbot effect which is fundamental to the operation of multimode interference couplers (MMI). Knowledge of the phase relation between the MMI ports is necessary to achieve correct operation of the GMZI OPA switch elements. An outline of the design procedures is given that can be applied to optimise the performance of MMI couplers and, as a consequence, the GMZI OPA switch elements. The Lüneburg Optical Transpose Interconnection System (LOTIS) is introduced as a potential solution to the problem of excessive insertion loss and cross-talk caused by the large number of crossovers in a switch fabric. Finally, the thesis explains how a Lüneburg lens may be implemented in a graded ‘metamaterial’, i.e. a composite material consisting of ‘atoms’ arranged on a regular lattice suspended in a host by nano-structuring of silicon waveguide slabs using a single etch-step. Furthermore, the propagation of light in graded almost-periodic structures is discussed. Detailed consideration is given to the calibration of the local homogenised effective index; in terms of the local parameters of the metamaterial microstructure in the plane and the corrections necessary to accommodate slab waveguide confinement in the normal to the plane. The concept and designs were verified by FDTD simulation. A 4×4 LOTIS structure showed correct routing of light with a low insertion loss of -0.25 dB and crosstalk of -24.12 dB. An -0.45 dB excess loss for 2D analysis and an -0.83 dB insertion excess loss for 3D analysis of two side by side metamaterial Lüneburg lenses with diameter of 15 μm was measured, which suggests that the metamaterial implementation produces minimal additional impairments to the switch.

Ce travail de thèse porte sur la caractérisation et l'optimisation du spot de focalisation d'un objectif de microscope de grande ouverture numérique pour des applications d'imagerie super-résolue et de nanofabrication.Dans la première partie, nous avons systématiquement étudié les distributions de polarisation et d'intensité du faisceau laser dans la région du point focal en fonction de différents paramètres du faisceau incident tels que la phase, la polarisation, l’amplitude ainsi que l'influence du milieu de propagation, tel que l’indice de réfraction. Nous avons mis en oeuvre différentes méthodes théoriques pour contrôler et manipuler les distributions de polarisation et d'intensité du spot de focalisation. Ces prédictions théoriques sont vérifiées expérimentalement via un système optique confocal en mesurant l’image de fluorescence d’une nanoparticule d’or pour différentes caractéristiques.Dans la seconde partie de ce travail, une nouvelle microscopie basée sur le mécanisme d'absorption ultra-faible à un photon a été démontré théoriquement et expérimentalement. Le calcul théorique basé sur l'approche vectorielle de Debye, qui prend en compte l'effet d'absorption du matériau, montre qu'il est possible de focaliser le faisceau lumineux en profondeur à l'intérieur d'un matériau si celui-ci présente une absorption linéaire ultra-faible à la longueur d'onde d'excitation. Cette méthode, dite (LOPA), a ensuite permis de fabriquer des structures 2D et 3D submicrométriques, similaires à celles obtenues par la méthode utilisant l’absorption à deux photons. / Nowadays, far field optical microscopy is widely used in many fields, for fundamental research and applications. The low cost, simple operation, high flexibility are its main advantages. The key parameter of an optical microscope is the objective lens.This thesis's work focuses mainly on the characterization and optimization of the point spread function (PSF) of a high numerical aperture (NA) objective lens (OL) for applications of high resolution imaging and nano-fabrication.In the first part of the thesis, we have systematically investigated the dependency of polarization and intensity distributions of the focusing spot on numerous parameters, such as the phase, the polarization, and the beam mode of incident beam, as well as the refractive index mismatch. Then, we demonstrated theoretically different methods for manipulation of the polarization and intensity distributions of the focusing spot, which can have desired shapes and are useful for different applications. By using a home-made confocal microscope, we have experimentally verified some of the theoretical predictions, for example, vector properties of light beam under a tight focusing condition. In the second part of dissertation work, a new, simple and inexpensive method based on the one-photon absorption mechanism has been demonstrated theoretically and experimentally for 3D sub-micrometer imaging and fabrication applications. The theoretical calculation based on vectorial Debye approximation and taken into account the absorption effect of material shows that it is possible to focus the light tightly and deeply inside the material if the material presents a very low one-photon absorption (LOPA) at the excitation wavelength. We have then demonstrated experimentally that the LOPA microscopy allows to achieve 3D imaging and 3D fabrication with submicrometer resolution, similar to those obtained by two-photon absorption microscopy.

O cristalino se origina de um epitélio simples e cuboidal que recobre a vesícula óptica. Neste estádio, os filamentos de actina são distribuídos ao longo do eixo apicobasal. As células do ectoderma pré- placodal, em contato com a vesícula óptica, formam um epitélio pseudoestratificado, chamado de placóide do cristalino, com acúmulo de actina no domínio apical. Nós propusemos estudar o papel da proteína PAR3 e sua fosforilação no estabelecimento de actina apical. A superexpressão de PAR3 no placóide forma pontos ectópicos de PAR3 na membrana baso-lateral e induz o recrutamento de actina ectópica para esses pontos. O recrutamento de actina e aPKC ectópicos é independente do estado de fosforilação da treonina 833, resíduo localizado no domínio de ligação do PAR3 ao aPKC. Além disso, no ectoderma peri-placoidal, onde a actina localiza-se baso-lateralmente, PAR3 induz o recrutamento ectópico de actina apical e esse recrutamento é independente da fosforilação da treonina 833. Esses dados nos sugerem que PAR3 é suficiente para recrutar actina no placóide do cristalino. / The lens originates from a simple cuboidal epithelium that overlies the optic vesicle. At this stage, the actin filaments are distributed along its apical-basal sides. The pre-placodal ectoderm, in contact with the optic vesicle, forms a pseudostratified tissue, the lens placode, with accumulation of actin network at the apical domain. Here, we focused on the role of the polarity protein PAR3 and its phosphorylation in the establishment of this apical actin network. Overexpression of PAR3 in the lens placode, induced formation of ectopic actin clusters in the basolateral membrane of the lens placode. The formation of these actin clusters, as well as recruitment of aPKC was independent of Threonine 833 phosphorylation at the PAR3 aPKC-binding site. In addition, PAR3 induced ectopic actin networks in the apical membrane of the periplacodal ectoderm independent of the Threonine 833 phosphorylation. Taken together, these data suggest that PAR3 is sufficient for actin recruitment in the lens placode.

This study demonstrates the presence of protein kinase C activity in both cytosolic and membrane fractions of bovine lens epithelial cells in culture. Protein kinase C activity is similar in normal and hyperglycemic cells. Furthermore, the ability of the enzyme to translocate from the cytosol to the membrane following phorbol ester treatment is unimpeded by hyperglycemic conditions. Moreover, protein kinase C activation had no effect on myoinositol uptake either in normal cells or in cells exposed to hyperglycemic conditions.

For the purpose of an future machine vision system development in Tyco Electronics Czech s.r.o. I have developed Cognex Designer template. Template will serve as a flexible basis for further development of camera applications on the Cognex VC5 industrial computer. The functionality of the program template has been successfully verified by modifying it to a particular application of the laboratory manual station used to measure the parameters of the manufactured connectors. A camera with lens and lightning was chosen and installed on the station. DIO communication was put into operation between VC5 and PLC system. The application has been calibrated and verified as a measurement system using MSA Type I and Capability study standard methods.

This thesis is focused on possibilities of high-speed digital cameras and their use in different fields of industry. It describes the mechanism of chip forming in orthogonal turning. Subsequently experiments focused on comparison and select the right lens and method of illumination are implemented. These findings are then used in obtaining the record of chip forming by using high-speed digital camera. Key words

This thesis deals with computing of the magnetic lens with a perturbed pole piece due to manufacturing imperfections. Two possible ways of calculation are discussed - the perturbation theory and 3D computing. Three methods for evaluating axial multipole field functions from 3D fields are introduced. Beam spots in the image plane and aberration coefficients are computed and results obtained by the application of perturbation theory are compared to results evaluated from 3D simulations. Consequently, a suitability of using the perturbation theory is discussed.

The thesis deals with the optimization of process parameters in the oxidative laser cutting of structural 20 mm thick steel with regard to the type of material, the resulting roughness of the cut and the resulting price of the product. In line with the literary study and the Taguchi method, an experiment was developed. The cutting speed, laser performance, cutting gas pressure, and focal position were controlled during the experiment. Sample sets were cut with 7.5" and 10" focusing lens from the TATA STEEL S355MC and SSAB LASER 355 MC steels. According to ČSN EN ISO 9013, the samples were evaluated for roughness. Then micro and macro structures were evaluated, and compare the hardness according to Vickers. In conclusion, technical and economic evaluation was determined.

Aus der Einleitung: "Das selektive Elektronenstrahlschmelzen (engl. Electron Beam Melting (EBM®)) ist ein pulverbettbasiertes additives Fertigungsverfahren, mit dessen Hilfe metallische Bauteile schichtweise hergestellt werden können. Der schematische Aufbau einer entsprechenden Anlage ist in Abbildung 4 dargestellt. Dabei erfolgt die Strahlerzeugung im Bereich 1 (die Kathode besteht entweder aus Wolfram oder bei den neuesten Systemen aus einkristallinem LaB6). Die Strahlablenkung durch ein elektromagnetisches Linsensystem erfolgt im Bereich 2. Der Bereich 3 ist die eigentliche Baukammer, in der sich unter anderem die Vorratsbehälter für das Pulver, das Rakelsystem sowie die Komponenten des Bauraums (Käfig mit Hitzeschild, Bauplattform mit Startplatte) befinden. ..."

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