This thesis deals with design of the reflector assembly line. The document contains the analysis of the customer requirements sheet. In short there is written how to put the parts of the reflector together. The Poka-Yoke method is properly described in this work too. This method is used to design of the actions, which are trying to decrease the risk level of wrong reflector composition as low as it is possible. FMEA and PFMEA methods are explained in theory. There is the plan how to make the analysis too. The instrumentation of one part of the line is designed according to this analysis and according to the customer requirements. The OEE pointer is used to test the right effect of the Poka-Yoke method. The next aim of this thesis is to compare chosen PLCs for control of the assembly line and to choose one of them. On the base of the analysis there is designed the control program in the flowcharts form. One part of this thesis is focused on design of the visualization for the chosen operational panel.

The diploma thesis deals with a design solution of an astronomical mirror telescope, also called Newton reflector on the Dobson Altazimuth mount. The design focuses on the determination of appropriate optic parameters and mounting parameters, on the new styling and shape solution with an emphasis on technical, operational, ergonomic and aesthetic requirements. The main benefit of the design is the simplicity of compilation and decompilation of entire device, intuitive control and safe usage and shape compactness of the whole appliance. I designed the device in the light of the fact that it is used mainly in complete darkness, and the colour solution corresponds to the fact.

The aim of this diploma thesis is to design a suitable reflector concentrating a light beam into a circular hole in a gobo. The light beam behind the screen should have good efficiency and at the same time good homogeneity. For the reflector design and analysis a software for designing optical systems called LightTools was used. The reflector was designed by six different methods. Several smooth and several faceted reflectors were designed. The selected reflector was analyzed in combination with a varifocal lens. For selected reflector was designed mechanical store with respect to the anticipated operating conditions. This thesis serves as the basis for the producing of the reflector.

Cette thèse a pour but de mettre en avant les récentes avancées dans le domaine des métasurfaces. Ces structures ont été utilisées dans le but d’améliorer les performances des antennes classiques ou de concevoir de nouveaux concepts d’antenne. Les travaux menés s’inscrivent dans le cadre d’une collaboration avec des partenaires industriels qui sont Airbus Safran Lunchers, Airbus Group Innovations et le CNES. La thèse est organisée en deux parties. La première partie est consacrée aux métasurfaces utilisées comme des surfaces partiellement réfléchissantes (SPR) pour concevoir des antennes à cavité Fabry-Perot. Un modèle analytique permettant de prédire le dépointage du faisceau d’antenne par une modulation de la phase sur la SPR a été développé. Ensuite, un nouveau concept de métasurface permettant de réaliser du dépointage de faisceau est proposé. Il consiste à appliquer un gradient de phase en faisant varier l’indice effectif le long du substrat diélectrique de la SPR. La deuxième partie de cette thèse est quant à elle consacrée à la conception d’une métasurface active permettant d’émuler plusieurs fonctions. Dans un premier temps, la métasurface est utilisée comme un réflecteur présentant une reconfigurabilité fréquentielle et angulaire. Ensuite cette métasurface est utilisée comme polariseur reconfigurable où une polarisation linéaire de l'onde incidente est convertie en polarisation circulaire. Enfin, la dernière étude concerne l’utilisation de la métasurface active pour la réalisation d’une antenne à réflecteur cylindro-parabolique et à réflecteur dièdre reconfigurables. / This thesis aims at highlighting recent advances in the field of metasurfaces. These structures have been used to improve the performances of conventional antennas or to design new antenna concepts. The work has been carried in the framework of a collaboration with industrial partners, namely Airbus Safran Launchers, Airbus Group Innovations and CNES. The manuscript is organized into two parts. The first part is devoted to metasurfaces used as partially reflecting surfaces (PRS) to design Fabry-Perot cavity antennas. In this part, an analytical model allowing to predict the beam steering angle by a phase modulation along the PRS is developed. Then, a new concept of metasurface allowing to steer the main antenna beam is proposed. It consists in applying a phase gradient by varying the effective index of the substrate that constitutes the PRS. The second part of this thesis is devoted to the design of an active metasurface that allows emulating different functionalities. First, the metasurface is utilized as a reflector with frequency and steering reconfigurability characteristics. Then, this metasurface is used as a reconfigurable polarizer where linearly polarized incident waves are converted into circularly polarized ones. Finally, the last study concerns the use of the active metasurface for the design of reconfigurablecylindro-parabolic and corner reflector antennas.

RECCO AB är ett företag som utvecklar räddningssystem för lavinolyckor. Systemet fungerar genom en RFID tag (reflektor) och en detektor. Detektorn känner av reflektorn som sitter på jackan, hjälmen, skon eller pjäxan upp till 200 meters avstånd eller 30 meter genom snön. Detektorn används av erfaren lavinräddningspersonal. RECCO ska implementera reflektorer i vandringsskor för att söka efter människor som är i skogen och uppe i bergen. Syftet med examensarbetet är att utveckla en skotestmaskin som ska kunna testa livslängden på reflektorn. Bakgrundsundersökningen genomfördes genom en informationssökning om biomekanik i ben och fot, olika benrörelser som kan påverka skon, olika typer av vandringsskor och olika skotestmaskiner som finns ute på marknaden idag. Genomförandet av projektet inleddes genom ett test för att undersöka hur stora krafterna är som påverkar reflektorn i skon. Testet genomfördes med en tryckkänslig sensor och en Arduino UNO. Den maximala kraften på reflektorn blev 7.1 N. Därefter gjordes en brainstorming som resulterades i sju olika koncept. Koncepten vägdes emot varandra med hjälp av en PUGH matris, som resulterade i att ett koncept valdes att gå vidare med. Analysen av konceptet genomfördes med Solidworks, Matlab och ADAMS. Med SolidWorks gjordes detaljerade ritningar och ett montage av modellen. Med Matlab gjordes beräkningar på lagerhus, glidlager, kulbussning och motor. ADAMS användes för att simulera rörelsen och för att verifiera Matlab-beräkningarna. Resultatet av slutprodukten blev lyckat. Maskinens rörelse och de påverkande krafterna på reflektorn efterliknar testet som genomfördes i början av projektet. Eventuella förbättringar som kan utföras är inköp av en starkare motor för att uppnå en mer konstant hastighet eller ett svänghjul för att minska påfrestningarna på motorn. För vidare arbete på slutprodukten kan RECCO programmera en strömbrytare som stänger av motorn vid uppnått antal cykler. / RECCO is a company that develops rescue system for avalanche accidents. The system works by a RFID tag (reflector) and a detector. The detector senses the reflector that is attached to jackets, helmets, shoes and ski boots up to 200 meters or 30 meters through the snow. The detector is used by experienced avalanche rescue groups. RECCO will implement reflectors in hiking shoes to search for people who are in the woods and in the mountains. The purpose of this master theses is to develop a shoe test machine to be able to test the service life of the reflector. The background study was performed by an information search about the biomechanics of the leg and foot, different leg movements that may affect the shoe, different types of hiking shoes and several shoe test machines available on the market today. The implementation of the project began with a test to examine how large the forces are on the reflector acting in the shoe. The test was conducted by a pressure sensitive sensor connected to an Arduino UNO. The maximum force on the reflector was 7.1 N. This was followed by a brainstorming session that resulting in seven different concepts. The concepts were then evaluated against each other using a PUGH matrix, which resulted in a concept for further development. The analysis was conducted using SolidWorks, Matlab, and ADAMS. Detailed drawings and assembly of the model were made using SolidWorks. The calculations were made on bearing housings, plain bearings, linear ball bearing and the motor using Matlab. ADAMS was used to simulate the movement and to verify the Matlab calculations. The result of the final concept was succeeded. The machine's movement and the influencing forces on the reflector mimic the performed test that was made at the beginning of the project. Improvements that can be done is to change to a more powerful motor to achieve a more constant speed or a flywheel to reduce the strain on the motor. For further work RECCO can program a switch that turns off the motor when the number of cycles are achieved.

Récemment, de nouvelles techniques ont été développées pour la fabrication des réseaux de Bragg à profil complexe. Ces composants photoniques sont utilisés dans plusieurs applications émergentes telles que la compensation de la dispersion pour les systèmes de communication de longue portée, les lasers à fibre, multiplexeurs et détecteurs optiques. Le diagnostic après inscription devrait fournir les informations nécessaires pour l’amélioration de la fabrication des réseaux de Bragg. Nous savons que les propriétés spectrales du réseau de Bragg sont liées au profil d’indice Δn. Les techniques de mesure directes, telles que la diffraction latérale de Krug, permettent de retrouver l’amplitude de modulation d’indice le long du réseau. Cependant, ces techniques sont insensibles aux fluctuations de phase. Une méthode alternative de caractérisation indirecte fondée sur l’algorithme de Layer-Peeling (LP) a été proposée. Toutefois elle ne peut pas être appliquée à la caractérisation des réseaux longs en raison de la propagation du bruit de calcul. Dans cette thèse nous avons présenté une nouvelle technique pour la mesure directe de l’amplitude et de la phase du profil d’indice le long du réseau de Bragg fondée sur la luminescence bleue (LB) induite par l’irradiation UV. Nos résultats expérimentaux de la mesure du profil de modulation d’indice sont en bonne correspondance avec la méthode de Krug. La méthode que nous proposons peut être appliquée à la caractérisation des réseaux longs. Elle permet de retrouver simultanément l’amplitude de modulation d’indice Δnac(z), la fonction du chirp et détecter le changement de l’indice moyen Δndc(z). / N the last decade new techniques were developed for fabrication of sophisticated Fiber Bragg Gratings (FGBs). This has been motivated by the emergence of many applications such as dispersion compensation for long-haul communication systems, DFB fiber lasers, optical add/drop multiplexers, and optical sensors. Post-fabrication diagnostics should provide relevant information to enhance the FBG fabrication process. It is well known that the FBG spectral properties are related to the index profile Δn. Direct measurement techniques, such as the side diffraction method reported by P. Krug, allow determining the index modulation amplitude along the FBG. Nevertheless, these techniques provide no information about phase fluctuations. An alternative method of indirect characterization, based on the Layer-Peeling (LP) algorithm, consists in Bragg grating profile reconstruction from its complex reflectivity. However, the LP method is unstable when applied to characterize long FBGs (>1mm) due to the error propagation effect. In this thesis we have shown the principle of a novel technique for the direct measurement of amplitude and phase variations of the index modulation along an FBG based on the blue luminescence (BL). Our experimental results are in a good agreement with the according Krug characterization. The proposed method of FBG characterization in amplitude and phase using the UV induced BL can be applied to long gratings (up to tens of centimeters) having complex index modulation profiles. It allows retrieving simultaneously the index profile modulation Δnac(z) and the chirp function, localizing phase shifts, and also detecting the mean index change Δndc(z).

The theme chosen for the dissertation is based on the research which deals with the question how to transform a real perception into abstraction. In a free way, I am inspired by my abstract paintings created through all my master's degree study. For a long time, the subject matter of my paintings has been the blending of structure, light and landscape. By gradual simplyfication and penetration of scenery motives with arquitecture and living nature, I try to create a complex piece of work. This abstract composition exposes always with particular impression of landscape's mood. It also stylizes a question,what we are focusing on and where we are looking, while being fascinated by the scenery - when staring into space.

This report describes computer studies which were done to determine the effect on burnup of modifying the heavy water reflector in a 600 MWe CANDU-PHW reactor. It is shown that the burnup penalty increases rapidly as the reflector thickness is reduced. The burnup penalty is significantly lower for mixed reflectors in which some of the heavy water in the outer region of the reflector is replaced by graphite, an organic liquid, or light water, while maintaining the original reflector thickness. / Thesis / Master of Engineering (MEngr)

A new fully integrated wavelength stabilization scheme based on grating-coupled surface-emitting lasers is explored. This wavelength stabilization scheme relies on two gratings. The first grating is fabricated on the p-side of the semiconductor laser in close proximity to the laser waveguide such that it couples light out of the guided mode of the waveguide into a propagating mode in the substrate; this grating is known as the grating coupler. The second grating is fabricated on the n-side of the substrate such that for the stabilization wavelength, this second grating operates in the Littrow condition and is known as the feedback grating. Furthermore with the proper design of the two gratings, the feedback grating will operate under total internal reflection conditions allowing a near unity retro-reflection of the light of the stabilization wavelength. The grating coupler and feedback grating together comprise a dual grating reflector (DGR). The DGR wavelength stabilization scheme is investigated both theoretically by means of numerical modeling and experimentally by integration of a DGR as a wavelength selective reflector into a single quantum well semiconductor laser with a gain peak centered at 975nm. Numerical modeling predicts a peak reflection of approximately 70% including losses and a spectral width of 0.3nm. The integration of a DGR into a semiconductor laser proved both the efficacy of the scheme and also allowed us to experimentally determine the effective reflectivity to be on the order of 62%; the spectral width of light output from these devices is typically on the order of 0.2nm. Furthermore, these devices had light-current characteristic slopes greater than 0.84W/A operating under continuous wave conditions. The DGR was then modified to provide a reflection with two spectral peaks. A semiconductor device incorporating this dual wavelength DGR was fabricated and tested. These devices showed a peak optical power of in excess of 5.5W and a light-current characteristic slope of 0.86W/A in quasi continuous wave operation; these devices also exhibit a large operating current range in which both wavelengths have comparable output powers. Another modified DGR design was investigated for the purpose of providing an even narrower spectral reflection. Devices incorporating this modified design provided an output with a spectral width as narrow as 0.06nm. DGRs were also integrated into an extremely broad area device of an unorthodox geometry; square devices that lase in two orthogonal directions were fabricated and tested. The last idea investigated was combining a DGR wavelength stabilized laser with a tapered semiconductor optical amplifier into a master oscillator power amplifier device, with the optical coupling between the two components provided by identical grating couplers disposed on the p-side surfaces of each of the devices. These master oscillator power amplifiers provide a peak power of 32W when operating under quasi continuous wave operation.

Photonic power converters (PPCs) are one of the main components of optical power transmission systems, converting optical power injected by a monochromatic optical source (laser or LED) to electrical power via the photovoltaic effect. This thesis focuses on designing and optimizing ultra-thin single junction InAlGaAs PPC with integrated back reflectors (BR) for operation at the telecommunications wavelength of 1310 nm and numerically studies the light trapping capability of three BR types: planar, cubic nanotextured, and pyramidal nanotextured. Optical simulations were performed by coupling finite difference time-domain (FDTD) calculations with a particle swarm optimization, while electrical simulations were carried out by the finite element drift-diffusion method. With 90% absorptance, optoelectrical simulations revealed that ultra-thin PPCs with 5.6- to 8.4-fold thinner absorber layers can have open circuit voltages (Voc) that are 9-12% larger and power conversion efficiencies that are 9-10% (relative) larger than conventional thick PPCs. Of the studied BR designs, pyramidal BRs exhibit the highest performance for ultra-thin designs, reaching an efficiency of 43.2% with 90% absorptance, demonstrating the superior light trapping capability relative to planar and cubic nanotextured BRs. The sensitivity of optical absorptance to variations in device thickness and incident light wavelength is also investigated numerically in thin PPCs with planar and pyramidal nanotextured BRs. Optical simulation results revealed that BR-induced resonances shift from constructive to destructive interference with thickness variations of ~100 nm and ~70 nm in planar and pyramidal nanotextured BRs, respectively. Also in PPCs with pyramidal BR, a 50 nm variation of the nanotextures’ geometry (base width and height of pyramids) drops the absorptance by more than 25% (absolute).