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Leakage of information through existing fibre optic infrastructures inside buildings
Kyselova, Yuliia ; Dejdar, Petr (referee) ; Münster, Petr (advisor)
The bachelor thesis deals with the possibilities of detecting acoustic and mechanical vibrations through existing optical data infrastructures inside buildings. The work includes a description about optical fiber and a theoretical analysis of the possibilities of implementing data distribution inside buildings, it also includes an analysis of methods for implementing optical fiber microphones. In the practical part of the work, the measurement was performed with an optical fiber microphone and then using an interferometer and a sensor based on the polarization method.
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Dynamic laser interferometer
Chovaneček, Libor ; Drexler, Petr (referee) ; Fiala, Pavel (advisor)
The theme of this bachelor´s project is dynamic laser interferometer. The project is firstly focused on theory, where it explains the term of interference and principle of operation of interferometer on specific types of interferometers. Different types of lasers used in interferometers are mentioned there. The next part of this paper is focused on assemblage of interferometer with description of particular parts. There are mentioned two methods of signal processing. The last part deals with confirmation of proper functioning of measuring system.
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Optical setup for torque detected electron spin resonance spectroscopy
Kern, Michal ; Vetushka, Aliaksei (referee) ; Neugebauer, Petr (advisor)
Táto diplomová práca sa venuje vylepšeniu spektroskopu Torzne Detegovanej Elektrónovej Spinovej Rezonancie (TDESR) výmenou aktuálnej kapacitnej detekcie výchylky ohybného ramienka za optické metódy. Práca popisuje základy Elektrónovej Spinovej Rezonančnej (ESR) spektroskopie s dôrazom na TDESR a tému magnetizmu jednomolekulových magnetov. Následne je vysvetlená detekcia výchylky ramienka pomocou odrazu laserového zväzku a interferometrie. Všetky kroky nutné k skonštruovaniu spektrometra a jeho uvedenia do prevádzky sú podrobne popísané. Pomocou detekcie odrazu laserového zväzku sme úspešne získali vysoko kvalitné TDESR spektrá kryštálu jednomolekulového magnetu Fe4. Týmto meraním sme dokázali vhodnosť použitia tejto metódy a jej výraznú prevahu nad pôvodnou kapacitnou detekciou, najmä v oblasti kvality, rozlíšenia a rýchlosti. Zároveň sme na ďaľšie vylepšenie TDESR spektrometra navrhli a zostrojili zostavu využívajúcu na detekciu výchylky interferometer.
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Optical fiber sensor based on Michelson interferometer
Kopáč, Ondřej ; Grenar, David (referee) ; Čučka, Milan (advisor)
This bachelor thesis deals with description and simulation of Michelson unbalance interferometer and description of fiber optic sensors. The simulation is realized by MatLab. The thesis also described basic optical phenomena, types of optical fibers and two types of interferometric detection. The thesis also deals with description of measurements and their results.
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Utilization and Suppression of Birefringence Phenomena in Optical Fiber Sensory Applications
Motúz, Rastislav ; Hudcová, Lucie (referee) ; Vlček, Čestmír (referee) ; Drexler, Petr (advisor)
The thesis deals with integral and distributed optical fiber sensors of electric current. In the area of integral sensors the analysis is performed by Jones matrix calculus and the simultaneous influence of induced circular and undesired linear birefringence using an ortho-conjugation retroreflector. Furthermore, the proposed conjugation loop variant using half-wave phase retarders is analyzed. The theoretical conclusions are confirmed by simulation and experimental measurement. In the field of distributed fiber optic sensors, analysis and simulation for the detection of plasma currents in thermonuclear fusion reactors, based on the POTDR technique, is performed. An improvement procedure is proposed for circular-shaped vacuum vessel reactors. Plasma current detection procedure in divertor-type reactors have been newly designed and simulated to investigate the effect of the OTDR detector noise on plasma current detection accuracy.
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Angular velocity measurement with fiber optic interferometer
Sodomka, Pavel ; Šedivá, Soňa (referee) ; Havránek, Zdeněk (advisor)
This bachelor thesis deals with the proposal and implementation of optic-fibre interferometer using the Sagnac phenomenon which measures the angular speed. In the theoretical part of this work, the possible interferometers are closer described and specified, base of wave interference, problems of the rotatory movement. The Sagnac phenomenon is explained and described here. Further the possible constructions of the optical-fibre interferometers for the measurement of the angular speed, including the described errors, which prevent the correct assembling and the implementation of the sensor. In the practical part of this work, the optical-fibre interferometer with the minimal balanced configuration. The individual optical and optical-fibre elements are selected and described to the given configuration, such as the source of radiation, polarizer, controller of polarization, divider, phase modulator, isolator, detector, optical fibre and optical-fibre coil. There is the specified and based problem which did not allow to successfully finish the assembled optical-fibre interferometer. In conclusion of this work there is the recommendation how to solve the caused problem.
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Fiber optic interferometry
Srnský, Petr ; Urban, František (referee) ; Čučka, Milan (advisor)
The aim of the diploma thesis is theoretical analysis of optical fiber sensory sensing using coherent and incoherent interferometry, creation of simulation models of interferometers and their practical measurement. The first part deals with the description of basic physical principles and interferometers. In the second part the thesis deals with the description and design of optical microphones, which are based on the principles of physical interferometers Michelson and Mach - Zehneder interferometer. Both models are simulated in the VPIphotonics simulation environment. In the third part of the thesis, both models are assembled and measured. The last part of the thesis presents the differences between the interferometers and the results of the measurements.
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Simulation of Mach Zehnder interferometer
Rozsypal, Filip ; Münster, Petr (referee) ; Čučka, Milan (advisor)
This bachelor thesis deals with the simulations of Mach-Zehnder and Michelson interferometer. These simulations are realized by VPIphotoncs and MatLab. The thesis also describes the optical and physical phenomena, the usage and the principle of operation of interferometers and results of measurements with validation of the basic work of both interferometers.
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Influence of magnetic and electromagnetic fields on signals transmitted by optical fibres
Schneider, Tibor ; Vrba, Kamil (referee) ; Münster, Petr (advisor)
The diploma thesis deals with the influence of magnetic and electromagnetic fields on signals transmitted by optical fibers. Subsequently, the results of individual measured values are evaluated and analyzed, which were measured using an interferometer and a polarimeter. The first part deals with the theoretical analysis of the principles of interference and polarization of light. It further explains the basic operation of the above-mentioned devices as well as the immunity of the optical fiber to EMI. The second part of the work presents selected devices and technologies that were used as a source of electromagnetic or magnetic radiation. Subsequently, individual phenomena are plotted both in the course of time and with the help of a spectrogram or Poincaré sphere. From the measured results we can conclude that the commonly available technologies, which were selected for the diploma thesis, will not cause greater negative problems to the signal on measured frequencies in optical fibre, that could degrade the transmitted signal.
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