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  • About
  • The Global ETD Search service is a free service for researchers to find electronic theses and dissertations. This service is provided by the Networked Digital Library of Theses and Dissertations.
    Our metadata is collected from universities around the world. If you manage a university/consortium/country archive and want to be added, details can be found on the NDLTD website.
1

Měření vlastností polarizovaného světla na výstupu vlnového multiplexu a jeho optimalizace pro použití v senzorové technice / Measurement of polarized light properties on the dense wavelength division multiplexing in optical-fiber sensor systems

Bučko, Kristián January 2021 (has links)
The polarization of light is one of the most remarkable phenomena in nature and has led to many discoveries in the optical-telecommunications sphere. The master's thesis describes the basic knowledge about polarized light, which includes the types of light polarization, the issue of Poincaré sphere, polarizing ellipse, etc. Emphasis is also placed on the measurement of optical power, where the analysis of various types of photodetectors and also polarimeters was performed. In the practical part of this work, the design of the workplace itself is described in the diagrams. Also, all devices in the workplace are analyzed and subsequently demonstrated measurement in several scenarios. The final chapter is a discussion with the measured results and graphical dependencies, comparison and analysis of results.
2

Automatizované měření polarizačních vlastností optického svazku / Automated measurement of polarisation properties of an optical beam

Březina, Vojtěch January 2014 (has links)
Diploma thesis deals with polarization properties of an optical beam and the determination of its polarization state by means of the proposed automatic measurement method. Furthermore the influence of an environment on the polarization state of the optical wave is studied. At the beginning of this thesis the fundamental terms with respect to the wave polarization including the description of the polarization devices are presented. In conclusion a method for an automated experimental workplace for the measurement of the polarization properties using Poincare sphere and Stokes parameters is designed and verified.
3

Nouveaux systèmes de contrôle de la polarisation de la lumière par effets non lineaires dans les fibres optiques / All-optical polarization control by nonlinear effects in optical fibres

Morin, Philippe 16 July 2013 (has links)
Ce mémoire présente les travaux effectués sur le développement d’un dispositif tout-optique de contrôle de l’état de polarisation de la lumière, appelé attracteur de polarisation. En effet, cette caractéristique de la lumière demeure une variable incontrôlable qui peut dégrader les performances des dispositifs tout-optiques. Basé sur l’interaction non linéaire entre deux ondes contrapropagatives au sein d’une fibre optique, ce dispositif permet de contrôler l’état de polarisation de la lumière sans pertes dépendantes de la polarisation.Il est tout d’abord effectué une étude approfondie des propriétés de l’attracteur de polarisation qui conduit au contrôle et à la stabilisation de l’état de polarisation d’un flux de données optiques aux formats NRZ et RZ cadencé à 10 Gb/s dans des fibres de plusieurs kilomètres. Par la suite, cette fonction de régénération tout-optique est associée à d’autres fonctions de régénération telles que l’amplification Raman et le régénérateur de Mamyshev dans le but de régénérer des flux de données optiques à des débits supérieurs à 10 Gb/s.Enfin, une extension de l’attracteur de polarisation, appelé Omnipolariseur, est étudiée où la lumière interagit avec elle-même grâce à un dispositif de réflexion inséré à l’autre extrémité de la fibre optique. La lumière est alors capable d’auto-organiser son état de polarisation, ce qui démontre la capacité de l’Omnipolariseur par exemple à stabiliser l’état de polarisation d’un flux de données optiques RZ à 40 Gb/s à 1550 nm / This thesis deals with the work the development of an all-optical device for the control of the polarization state of light. Actually, this feature of light remains so far an uncontrolled variable, which can degrade the performances of all-optical systems. Based on nonlinear interaction between two counterpropagating waves inside an optical fiber, this device called polarization attractor allows to control the polarization state of light without polarization dependent losses.In a first part, we carry out extensive studies of the polarization attractor properties leading to the control and the regeneration of the polarization state of the 10-Gb/s NRZ and RZ telecommunication signals. Then, this all-optical regeneration function is associated with other regeneration functions, like Raman amplification and Mamyshev regenerator, in order to regenerate optical telecommunication signals at rates exceeding 10-Gb/s.Finally, we present an extension of polarization attractor, called Omnipolarizer, where the light interacts with herself by means of a reflective element inserted at the opposite end of the optical fiber. In that case, the light is able to organize its own polarization state, demonstrating the ability of Omnipolarizer to stabilize by example the polarization state of a 40-Gb/s RZ telecommunication signal at 1550 nm
4

Vliv dvojlomu jednovidových optických vláken na činnost polarizačního multiplexu / Influence of single mode optical fiber birefrigence for polarization multiplex

Šimák, Petr January 2018 (has links)
Thesis deals with polarization multiplexing and how birefringence influences polarization multiplexing. It also deals with polarization of light and how it can be described by Stokes and Jones vectors and also with visualiating polarization on Poincaré sphere. It also describes how information is transmitted in optical systems. At the end of the thesis is described design for polarization multiplexing at the lab.
5

Návrh optovláknového tepelného senzoru pro detekce narušení obranného perimetru / Design of optical fiber temperature sensor for detection of defense perimeter

Zámečník, Ondřej January 2021 (has links)
This diploma thesis deals with the issue of measuring the ambient temperature using a~single-mode optical fiber used as a temperature sensor. The thesis describes the basic knowledge about polarized light, its propagation in optical fiber and describes special fibers that preserve polarization. It also deals with the representation of polarization states on a Poincaré sphere and the use of Stokes and Jones vectors. In the practical part, several selected methods of optical signal supply to the temperature sensor are measured. Subsequently, the suitability of the given methods is evaluated from the measured results and the courses are compared with the records measured from real routes. This thesis aims to select a suitable connection of a temperature sensor for a long route of optical fiber and verify its functionality.
6

Měření tolerančního pole a vlivu dvojlomu na činnost polarizačního multiplexu / Tolerance zone and birefrigence influnce measurement on polarization multiplex

Štohl, Jakub January 2019 (has links)
The thesis deals with the measurement of tolerance zone and the influence of birefringence on the activity of polarization multiplex. The theoretical part deals with polarization of light, mathematical description using Stokes and Jones vectors and its representation by Poincaré sphere. It also deals with optical transmission and channel merging. The final part describes the designed measuring workplace and the measurement itself.
7

Realizace vysokorychlostního přenosového kanálu s využitím polarizačních rovin šíření světla / Transmission Broadband Channel Implementation Using Light Propagation Polarization Axes

Mafka, Martin January 2017 (has links)
The aim of this master’s thesis is to analyze ways of propagation light in optical fiber with two polarization planes. Theoretical part is focused to to the issue of polarized light, its mathematical description using Stokes and Jones vectors, the state of polarization on Poincare sphere and polarization multiplex. In the practicle part are first measured several laboratory measurements to verify the theoretical assumptions from the previous chapters. At the end of the thesis was constructed a functional polarization multiplex for wavelength 1550 nm.
8

Měření parametrů polarizovaného světla na výstupu optovláknového senzoru / Measurement of polarized lightparametrs measurement on the optical-fiber sensor output

Drábek, Jakub January 2018 (has links)
This master's thesis deals with the analysis of the optical power measurement using an optical fiber sensor. The thesis contains the theoretical background to understand the origin of polarization and its representation in space using Poincaré’s sphere and Stokes vectors. There is also a part describing optical performance measurement and the preview of analog measurements from various researches. Practical part focuses on verification of changes of fiber sensor parameters at temperature change in its surroundings and this part includes also additional suggestions for various types of measurements and verification of the function of the photodiode as an optical power transducer. Most measurements are based on the comparison of results obtained with the polarimeter. The results were plotted and discussed.
9

Vliv dlouhých optovláknových tras na polarizační stav světla a jejich využití pro napájení polarizačních senzorů / Long optical fibre routes influence on the polarizing state of light and uses it for powering polarization sensors

Panascí, Marco January 2021 (has links)
This diploma thesis deals with the influence of long fiber optic paths on the polarization state of light and their use for powering polarization sensors. The aim of the diploma thesis was to design the arrangement of optical fiber components so that the polarization properties of light at the end of the path are further usable for sensory purposes. Four partial measurements with a long path (in a laboratory setting, laying in the ground, on a curtain, under the influence of external influence) and one measurement without a path under the influence of external influence were designed. The overall measurement results demonstrate that for the functional power supply of long-distance sensor systems, an existing single-mode fiber can be used (laid by laying in the ground), into which a light source for a given sensor system would be multiplexed. In the discussion, all types of measurements are analyzed and compared with each other. Finally, the overall result is summarized and applications are described in which such a sensor system could be used.
10

Měření vlastností polarizovaného světla na výstupu optovláknového senzoru / Measurement of polarized light properties on the opticla fiber sensor output

Velič, Ladislav January 2020 (has links)
birefringance, degreeofpolarization, polarization, Stokesvectors, Poincarésphere, state of polarization, optical power, sensoric fibre, polarization-maintaining fiber, polaroid, poalrimeter

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