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Design and verification of low temperature parts of UHV SEM/SPM stage
Pola, Tomáš ; Vlček, Ivan (referee) ; Urban, Pavel (advisor)
This thesis focuses on experimental verification and experimental-based improvements of designed low temperature parts of stage of the UHV SEM/SPM microscope, which operates in temperature range from 20 K to 700 K. The main focus is on the functionality verification of thermal insulation pad (InBallPad) as well as on the effect of length and contact quality of braid on minimal achievable temperature. The contact quality of sample holder with sample carrier realized with two springs is investigated together with influence of thermal contact resistances on achievable temperature. The thesis also contains a calculation model used for cooldown times and minimal temperature estimation. In the conclusion of this work several future experiments are suggested which could explain some of the observed, yet unexpected, phenomena.
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Measurement of diffusely reflecting surfaces using vortex topographic microscopy
Pola, Tomáš ; Baránek,, Michal (referee) ; Bouchal, Petr (advisor)
This thesis describes an innovative method for topographic measurement of diffuse surfaces. Tested surface is measured indirectly using nanoparticles distributed across the studied area. An image of every particle is captured by CCD camera as a double helix point spread function whose angular rotation corresponds to local surface height. Used point spread function is the result of an interference of non-diffracting vortex beams that are formed by a spiral phase mask from light originating from a nanoparticle. Diploma thesis presents an overview of current techniques for surface topography measurement. Next, working principle of proposed method is described and its experimental application is discussed. An influence of signal-to-noise ratio and image sampling on reconstruction precision is studied using numerical simulations and, as a result, optimal experimental parameters are proposed. Practical potential of the method is demonstrated by 3D reconstruction of planar and spherical surfaces in the depth range of up to 9 times the depth of focus of used microscope objective.
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Measurement of diffusely reflecting surfaces using vortex topographic microscopy
Pola, Tomáš ; Baránek,, Michal (referee) ; Bouchal, Petr (advisor)
This thesis describes an innovative method for topographic measurement of diffuse surfaces. Tested surface is measured indirectly using nanoparticles distributed across the studied area. An image of every particle is captured by CCD camera as a double helix point spread function whose angular rotation corresponds to local surface height. Used point spread function is the result of an interference of non-diffracting vortex beams that are formed by a spiral phase mask from light originating from a nanoparticle. Diploma thesis presents an overview of current techniques for surface topography measurement. Next, working principle of proposed method is described and its experimental application is discussed. An influence of signal-to-noise ratio and image sampling on reconstruction precision is studied using numerical simulations and, as a result, optimal experimental parameters are proposed. Practical potential of the method is demonstrated by 3D reconstruction of planar and spherical surfaces in the depth range of up to 9 times the depth of focus of used microscope objective.
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The Development of the Czech Economy due to the Financial Crisis of 2007–08
Pola, Tomáš ; Svoboda, Roman (advisor) ; Kopecká, Lenka (referee)
This bachelor work consists of the development of the Czech economy in relation to the financial crisis that occurred between 2007 and 2014. The focus is on the impact of the crises on key macroeconomic indicators of the Czech economy. The theoretical part of the work characterizes the concept of the economic crisis in the United States. The analytical part focuses on the immediate situation in Czech Republic, above all on the development of GDP, external economic relationships, measurements of unemployment, inflation and the government's fight against this crisis.
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Design and verification of low temperature parts of UHV SEM/SPM stage
Pola, Tomáš ; Vlček, Ivan (referee) ; Urban, Pavel (advisor)
This thesis focuses on experimental verification and experimental-based improvements of designed low temperature parts of stage of the UHV SEM/SPM microscope, which operates in temperature range from 20 K to 700 K. The main focus is on the functionality verification of thermal insulation pad (InBallPad) as well as on the effect of length and contact quality of braid on minimal achievable temperature. The contact quality of sample holder with sample carrier realized with two springs is investigated together with influence of thermal contact resistances on achievable temperature. The thesis also contains a calculation model used for cooldown times and minimal temperature estimation. In the conclusion of this work several future experiments are suggested which could explain some of the observed, yet unexpected, phenomena.
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