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COHERENCE-CONTROLLED HOLOGRAPHIC MICROSCOPY IN DIFFUSE MEDIA
Lošťák, Martin ; Komrska, Jiří (referee) ; Šerý, Mojmír (referee) ; Chmelík, Radim (advisor)
This thesis deals with imaging through diffuse media in coherence-controlled holographic microscope (CCHM) developed in IPE FME BUT. The mutual coherence function as well as the signal dependence on the lateral mutual shift between both arms of the CCHM are calculated. Both functions are related to each other. The latter dependence is measured experimentally. A principle of imaging with CCHM through diffuse media with both ballistic and diffuse light is explained by a simple geometrical model. This model is then verified experimentally by imaging a sample through diffuse medium. The point spread function (PSF) of CCHM for imaging through diffuse media is then calculated. Results of PSF calculation are proved experimentally.
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Fraunhofer diffraction by identical objects of the same orientation
Prokop, David ; Bouchal, Petr (referee) ; Komrska, Jiří (advisor)
The bachelor's thesis deals with Fraunhofer diffraction by identical objects of the same orientation. Main objective of my thesis is description of Fraunhofer diffraction for three different arrangements of holes along a straight line. In next part, the problem of random distribution of holes along straight line is set into plane. The outcome of my thesis is determination of deviations from regular array of holes. Next part of my thesis includes a description of Fraunhofer diffraction experiment. In final part of my thesis are pictures of diffraction phenomena, to illustrate results obtained from model of random distribution of holes.
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Numerical refocusing in a digital holographic microscope with a partially coherent illumination
Slabá, Michala ; Komrska, Jiří (referee) ; Chmelík, Radim (advisor)
The bachelor thesis deals with issue of numerical refocusing in a holographic microscope with partially space coherent light. The numerical refocusing is a computation of the complex amplitude of an image wave in planes differing from the image plane. The calculation of the region where the numerical refocusing is usable is based on application of Rayleigh-Sommerfeld diffraction integral and the Fresnel approximation of a spherical wave. The description of coherence state and propagation of partially coherent light follows from statistical methods in optical coherence theory. In this thesis the thickness of field is calculated where the numerical refocusing is usable. The thickness depends on microscope parameters - the size of the light source and parameters of lenses in microscope. The result is applied to the microscope in the laboratory IPE FME BUT.
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Superresolution in holographic microscopy
Říha, René ; Komrska, Jiří (referee) ; Chmelík, Radim (advisor)
An approach that uses a two dimensional phase grating in certain distance behind a specimen to enhance the resolution in digital holographic microscopy is proposed. By theoretical considerations and with simulations the properties of new the arrangement are explored and the method of numerical reconstruction is described. The proposed approach is verified by electromagnetic simulation. Technical aspects and potential difficulties aren't involved.
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Theoretical description of imaging by a digital holographic microscope
Slabá, Michala ; Komrska, Jiří (referee) ; Chmelík, Radim (advisor)
The diploma thesis deals with theory of imaging in a transmitted-light digital holographic microscope using partially coherent illumination. The influence of spatial and temporal coherence state on optical sectioning property is solved. The coherent transfer function is calculated. From this function imaging characteristics for a two-dimensional scattering object are derived depending on its defocus. Two different designs of microscopes developed in the Laboratory of optical microscopy in IPE FME BUT are considered.
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Political tabloid press on examples of titles "Na vlastní oči Praha 10" and "Na vlastní oči"
Komrska, Jiří ; Osvaldová, Barbora (advisor) ; Štoll, Martin (referee)
The main goal of this diploma thesis was to find patterns on the pages of Na vlastní oči (With One's Own Eyes) title that define gutter press in its specific form of political tabloid. The analysis was concerned with the time period from 2016 to 2019 during which the said title was published in total of four waves each of which related to the relevant pre-election campaign. The Na vlastní oči title was initially published anonymously and only later Jan Čížek, publisher of the regional town-hall newspaper and a Freedom and Direct Democracy Party (SPD) candidate, claimed to be the publisher. SPD subsequently became the final sponsor of the newspaper. In the first wave of publishing activity, the authors of the title focused on a disparaging campaign against the then-candidate for the Senate of the Parliament of the Czech Republic Parliament and, in a broader context, against the whole opposition within the City Council of the Prague 10 City Ward. In its later publications, the newspaper dealt mostly with topics aimed at spreading fear of an unspecified danger associated with the refugee crisis and concerns about the unknown in the form of the Islamic Religion which was always associated with the threat of terrorism. In the context of its election programme, SPD also communicated groundless criticism...
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Superresolution in holographic microscopy
Říha, René ; Komrska, Jiří (referee) ; Chmelík, Radim (advisor)
An approach that uses a two dimensional phase grating in certain distance behind a specimen to enhance the resolution in digital holographic microscopy is proposed. By theoretical considerations and with simulations the properties of new the arrangement are explored and the method of numerical reconstruction is described. The proposed approach is verified by electromagnetic simulation. Technical aspects and potential difficulties aren't involved.
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Objectivity of titles Informační servis and Rudé právo in the period November 1989 - December 1989
Komrska, Jiří ; Osvaldová, Barbora (advisor) ; Köpplová, Barbara (referee) ; Bednařík, Petr (referee)
The Bachelor Thesis "The Objectivity of the News of Informační Servis and Rudé Právo in the Period November 1989 to December 1989 " is devoted to describe the news content of the titles Rudé právo and Informační servis and their objectivity in the period November to December 1989. In particular, the qualitative method of content analysis was applied for the analysis. This is conceived as an interpretative analysis of source texts. The thesis describes the differences between the two titles and, especially, the development that the titles passed during the period under review working with the information and its interpretation. The research part of the thesis is supplemented by the theoretical and methodological parts. Part of the theoretical one is a description of the period and its media situation.
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Fraunhofer diffraction by identical objects of the same orientation
Prokop, David ; Bouchal, Petr (referee) ; Komrska, Jiří (advisor)
The bachelor's thesis deals with Fraunhofer diffraction by identical objects of the same orientation. Main objective of my thesis is description of Fraunhofer diffraction for three different arrangements of holes along a straight line. In next part, the problem of random distribution of holes along straight line is set into plane. The outcome of my thesis is determination of deviations from regular array of holes. Next part of my thesis includes a description of Fraunhofer diffraction experiment. In final part of my thesis are pictures of diffraction phenomena, to illustrate results obtained from model of random distribution of holes.
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COHERENCE-CONTROLLED HOLOGRAPHIC MICROSCOPY IN DIFFUSE MEDIA
Lošťák, Martin ; Komrska, Jiří (referee) ; Šerý, Mojmír (referee) ; Chmelík, Radim (advisor)
This thesis deals with imaging through diffuse media in coherence-controlled holographic microscope (CCHM) developed in IPE FME BUT. The mutual coherence function as well as the signal dependence on the lateral mutual shift between both arms of the CCHM are calculated. Both functions are related to each other. The latter dependence is measured experimentally. A principle of imaging with CCHM through diffuse media with both ballistic and diffuse light is explained by a simple geometrical model. This model is then verified experimentally by imaging a sample through diffuse medium. The point spread function (PSF) of CCHM for imaging through diffuse media is then calculated. Results of PSF calculation are proved experimentally.
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