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Measurement of laser beams parameters
Vrábel, Miroslav ; Kvíčala,, Radek (referee) ; Hudcová, Lucie (advisor)
his paper discusses the characteristics of laser radiation. Introduces the theory and in quite a description of the laser beam. To this end, experiments were compiled to measure the geometric and performance parameters, polarization and coherence. Emphasis is placed on the interdependence of the various parameters of laser radiation
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Measurement of relative variance of optical intensity
Vaníček, Jakub ; Kučera,, Petr (referee) ; Hudcová, Lucie (advisor)
The intention of this master‘s thesis is the measurment of relative variance of optical intensity. In the first place, I have been studied Kolmogorov cascade theory of turbulence and relative variance of optical intensity . In addition, I have been deal with turbulent cells, Gaussian beam, Top Hat beam and influence of the atmospheric turbulences on the intensity profile of the laser beam. Lastly I have been measured determine influence of the atmospheric turbulences on the intensity profile of the laser beam and I have been calculated relative variance of optical intensity. I have suggested the optimum beam profile in the turbulent atmosphere from acquired data.
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ThermaCAM PM595 in practical use
Švábeník, Petr ; Křivák, Petr (referee) ; Hudcová, Lucie (advisor)
The thesis presents study of generation of thermal (infrared) radiation, its properties and ways of measuring. The possible used sensors of this thermal radiation are described. A thermacam is using these sensing units so there are written benefits of this measurement. Some suggestions for practical use and specific submissions to measure are written.
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Influence of atmospheric turbulences on the optical beam
Bárta, Miroslav ; Wilfert, Otakar (referee) ; Hudcová, Lucie (advisor)
The aim of this thesis is to study a free space optics and its application in communication technologies. It describes possible interrupting impacts on the beamed optical signal, which are signal noise, attenuation of the atmosphere and atmospheric turbulence. The basis of the thesis is to describe the impact of the atmospheric turbulences on the optical beam. Fluctuation of optical intensity in the optical beam has been measured and index of refraction structure parameter calculated. With its assistance, turbulence rate has been determined.
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Digitalization of the optical intensity distribution scanning
Škrob, Robin ; Hudcová, Lucie (referee) ; Křivák, Petr (advisor)
This Master’s thesis solves a design and construction of device for gathering and transfer of data into computer. The device should replace graph plotter, by which is measured the optical intensity of a laser beam. From this characteristic it is possible to determine other parameters of the laser beam, such as halfwidth of the beam, angle of divergence and Rayleigh length. The described device - “data gatherer” - measures two voltage values – voltage detected on photodiode and voltage detected on distance moved by photodiode. Measured values of voltage are processed and sent through a serial line into the computer. A pre-amplifier is connected to the control part for both channels of measured values with possibility of amplification. Computer application, which performs graphic interpretation of the measured values, serves as user control peripheral. The product of this project is compact device operating under OS Windows with graphic output.
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Model of the metropolitan optical network
Prudík, Jiří ; Hudcová, Lucie (referee) ; Křivák, Petr (advisor)
The purpose of this master’s thesis is foremost to provide a simple guide how to build elements of optical metropolitan area network. The basic model consists to sequence of construction, network topology, passive and active parts. The collection contains examples of alternative technology such as Wireless LAN with different frequency. The optical network construction based on optical cable, fibres, splices, trays, adapters, connectors and active parts for example a lot of media convertor models. After that there are demonstrating type of wavelength division multiplexer used in metropolitan area network – passive planar PCL splitter. One of the passive planar splitter are used to increase optical fibre channel. At the end of the collection a simplified examples of used measurements – optical time domain reflectometry and optical fibre transmission. Contains standard protocols or reflectogram. The conclusion of this thesis summarizes costs of FTTb (Fibre To The Building) model of optical metropolitan area network in Czech republic and future contribution for society.
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Optical signal detection and maesurement of low deflections using the Michelson interferometer
Kováč, Petr ; Hudcová, Lucie (referee) ; Křivák, Petr (advisor)
The dissertation is concerned with the description and utilization of interference of two coherent optical rays. In addition, the conditions of coherence and its connections with the occurance of interference are discussed. Michelson's interferometer is used for the practical utilization of the interference effect. The possibility of measuring relatively small changes is demonstrated - deviation of piezocrystal, measurement of the coherent length of optical source and measurement of the index of refraction of tramsparent materials. The manner of optical coherent detention and its utilization in optical communication systems is indicated. After demonstration of the principle was carried out the measuring of detection of optical signal modified by the external modulator.
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Coherent Analog Processing of Optical Information
Hrůza, Libor ; Hudcová, Lucie (referee) ; Wilfert, Otakar (advisor)
In my essay I show Fourier transform theory and applications in context with difraction theory especially Fraunhofer difraction. In part of the experiment, I set up an optical signal processing system. I take the Fourier transform of an input signal using a lens, filter the transform by placing various filters at the Fourier plane, and take the inverse transform. A simple optical bench consists of a laser, to produce a parallel, monochromatic beam which illuminates a specific area of the micrograph. Lens to focus the Fraunhofer diffraction pattern in the back focal plane of the lens. Mask transit contrived light or block out most of the noise in the diffraction pattern arising from image features. A reconstruction lens, placed behind the mask, refocuses the unobstructed rays and forms a filtered image. Optical diffraction provides useful information about the geometrical arrangement of subunits in the specimen. I make experiments for attestation on elementary objects and real images in mathematic program Matlab. From knowledge Fraunhofer difraction and organization of experiment I calculated size of circular object. I show practical using of Fraunhofer difraction and optical filtration. My essay give good introduction to the theory and techniques of optical filtration.
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Optical transmitter design
Vraspír, Marek ; Křivák, Petr (referee) ; Hudcová, Lucie (advisor)
This work dissert on proposal of optical ampifier excitor for transmission of information using optical enviroment. For proposition was chosen suitable transmission enviroment and LD diode that is used in optical communications. Accent was put at universal using of diode. Than was solved the modulation of input signal, it is used the „on-off“ keying, which is proceeded by integrated circuit, which is designed for none extreme transmission speeds. The work contains the solution of the potection of electrical circuit and LD diode against high current and thermal influences in transmitter.
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