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Quantiative biological microsocopy by digital holographyMann, Christopher J 01 June 2006 (has links)
In this dissertation, improved techniques in digital holography, that have produced high-resolution, high-fidelity images, are discussed. In particular, the angular spectrum method of calculating holographic optical field is noted to have several advantages over the more commonly used Fresnel transformation or Huygens convolution method. It is observed that spurious noise and interference components can be tightly controlled through the analysis and filtering of the angular spectrum. In the angular spectrum method, the reconstruction distance does not have a lower limit, and the off-axis angle between the object and reference waves can be lower than that of the Fresnel requirement, while still allowing the zero-order background to be cleanly separated. Holographic phase images are largely immune from the coherent noise commonly found in amplitude images. With the use of a miniature pulsed laser, the resulting images have 0.5um diffraction-limited lateral resolution and the phase profile is accurate to about several nanometers of optical path length. Samples such as ovarian cancer cells (SKOV-3) and mouse-embryo fibroblast cells have been imaged. These images display intra-cellular and intra-nuclear organelles with clarity and quantitative accuracy. This technique clearly exceeds currently available methods in phase-contrast opticalmicroscopy in both resolution and detail and provides a new modality for imaging morphology of cellular and intracellular structures that is not currently available. Furthermore, we also demonstrate that phase imaging digital holographic movies provide a novel method of non-invasive quantitative viewing of living cells and other objects. This technique is shown to have significant advantages over conventional microscopy.
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Development of confocal optical holographic microscopyMcLeod, Robert A. 06 September 2006 (has links)
Optical Confocal Holography is a combination of two well known concepts: confocal
microscopy and optical (laser) holography. Confocal microscopy places an aperture at a
conjugate focus to the specimen focus. This filters any rays that are not on the focus
plane, allowing a 3-dimensional image of the specimen to be built up over a set of planes.
Holography is the measurement of both the amplitude and phase characteristics of light.
Typically most methods only measure the amplitude of the image. The phenomenon of
interference allows the determination of the phase shift for a coherent source as well. The
phase information is directly related to the index of refraction of a material, which in turn
is a function of the temperature and composition. As a technique, confocal holography
holds promise to better characterize many physical processes in materials science, such as
combustion and convection. It also may contribute to the biological sciences by imaging
low-contrast, weak-phase objects. Thanks to the ongoing, continued improvement in
computer processing speed, it has recently become practical to interpret data from
confocal holography microscopy with a computer. The objective of the microscope is to
non-invasively measure the three-dimensional, internal temperatures and compositions
(e.g. solute/solvent gradient) of a specimen.
My contributions over the course of two years to the project were: generation and
optimization of an optical design with a software package known as Zemax; sourcing and
purchasing all components; formation of a CAD model of the microscope; experiments to
characterize building vibrations and air currents; and the development of software in
Visual Basic to simulate holograms and execute reconstruction algorithms for the specific
application of confocal holography.
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Laser surface micro/nano patterning for improving aerodynamic performanceOtanocha, Omonigho January 2016 (has links)
The use of ultrafast lasers in material surface engineering has gained pre-eminence in recent years. This is due to optimal utility arising from their versatility, better process control, repeatability and high precision fabrication, without need for post processing. Reported in this thesis are experimental results on the use of picosecond laser to produce micro-patterns on cyclone components and their effects on flow characteristics. Results show that micro- dimples achieved reduction in dust accumulation within a multi-cyclone system considered, up to 78%. These micro-dimples when applied on the cyclone roof effected a 3% reduction in inlet velocity and 5% reduction on the dynamic pressure across the cyclone, without dust introduction. Results support the possibility for energy savings, without compromise on cyclone overall separation efficiency. Findings further demonstrated the effects of micro-riblets on cyclonic airflow at the wall boundary. Research outcomes supported the view that surface roughness of the cyclone roof could contribute on its dust separation capacity. Injection moulding was used to produce bumps on ABS plastic materials utilising picosecond laser machined micro-dimples on H13 tool steel. A statistical model detailing the interactions between the critical factors involved with picosecond laser interaction with H13 for micro-patterning was proposed. Critical factors identified were laser fluence, scanning speed and number of laser scans. In addition, results demonstrated the suitability of predicting depth of 40 - 100 µm for H13 tool steel, with 96% accuracy. The findings in this research could be explored to develop embedded micro/nano-wires within riblets through injection moulding, to effect electrically biased charging within the internal walls of a cyclone to aid dust separation processes.
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Novos limites para o parâmetro deTsallis em um espaço de fases não comutativo, gravidade entrópica e equações de Friedmann não extensivasPaula, Rodrigo Machado de 19 February 2016 (has links)
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Previous issue date: 2016-02-19 / Este trabalho foi inspirado pelo artigo [1] “New bounds for Tsallis parameter in a noncommutativephase-spaceentropicgravityandnonextensiveFriedmannequations”. Inicialmente, é apresentada uma nova teoria que deriva a lei de gravitação de Newton, segunda lei e Relatividade Geral do ponto de vista termodinâmico. Além disso, é apresentada a teoria estatística não-extensiva de Tsallis onde sua principal característica é a inserção do parâmetro q que mede o grau de não-extensividade. Novos limites para este parâmetro são calculados, em um espaço de fases não-comutativo. As equações de Friedmann são derivadas a partir do princípio holográfico e uma generalização não-extensiva para estas equações também é apresentada. Ao final, é feita uma análise dos parâmetros cosmológicos incorporando-se propriedades não-extensivas. / This work was inspired by the article [1] “New bounds for Tsallis parameter in a noncommutative phase-space entropic gravity and nonextensive Friedmann equations”. First of all, it is presented a new theory that obtains Newton’s law for gravity, second law and General Relativity from termodynamics. Moreover, it is also presented the Tsallis’s nonextensive statistical theory where the principal feature is the insertion of q parameter which quantifies the degree of nonextensivity. New bounds are obtained for this parameter, in a noncommutative phase-space. The Friedmann equations are developed from holographic principles and a nonextensive generalization for this equations are also presented. Finally, it is made an analyses from cosmological parameters proposing nonextensivity properties.
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Rekonstrukční metody v holografické mikroskopii / Reconstruction methods in holographic microscopyFindejsová, Anna January 2019 (has links)
This master’s thesis focuses on the image reconstruction from holographic microscope. The first part of the thesis summarizes problems of holography, describes its principle and application particularly in live cell biology. In the second part the description of several methods used for off-axis hologram reconstruction is provided. The last part describes the implementation of the basic step in holographic reconstruction – the elimination of autocorrelation and twin image – and then also the reconstruction of 3D information of the sample.
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Příprava a charakterizace nanostruktur s funkčními vlastnostmi v oblasti plazmoniky / Fabrication and characterization of nanostructures with functional properties in the field of plasmonicsBabocký, Jiří January 2020 (has links)
Tato dizertční práce se zabývá výrbou a charakterizací plasmonických nanostruktur. Její první část začíná krátkým úvodem do plasmoniky s navazujícím přehledem metod, které jsou v dnešní době nejčastěji používány k výrobě a charakterizaci plasmonických nanostruktur. Druhá část se pak zaměřuje na samotný výzkum, který byl v rámci PhD studia realizován. Cílem prvních experimentů bylo prozkouat možnosti použití elektronové litografie za variabilního tlaku v procesní komoře pro výrobu plasmonických nanostruktur na nevodivých substrátech jako je např. sklo. Jelikož se jedná o materiály, které jsou velice často používány k přípravě plasmonických struktur pacujících v oblasti viditelného světla. Druhá sekce pak diskutuje některé specifické aspekty přípravy plasmonických mikrostruktur elektronovou litografií pro THz oblast. Poslední část se pak zaměřuje na funkční vlastnosti plasmonických nanostruktur, převážně pak na kvantitativní charakterizaci fáze dalekého pole indukovaného plasmonickými nanostrukturami a jejich aplikacemi v oblasti optických metapovrchů - uměle připravených povrchů, které mohou být použity jako planární optické komponenty. Práce demonstruje a diskutuje různé experimentální přístupy použití mimoosové holografické mikroskopie pro jejich charakterizaci.
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Optimalizace parametrů optické soustavy digitálního holografického mikroskopu pro odražené světlo. / Optimization of parameters of the optical system of reflected-light digital holographic microscope.Dostál, Zbyněk January 2009 (has links)
The diploma thesis deals with the construction design of reflective type of holographic microscope together with the proposal for the mechanical imposition of optical elements. Thesis contains parts where the illumination beam tracing through the optical system is calculated and discussed, followed up with the accuracy requirements for rectification mechanisms and their design. The three-dimensional model of modularly solved microscope is presented in conclusion of this thesis together with selected microscope sub-assemblies.
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Automatizace metody měření povrchových struktur reflexním digitálním holografickým mikroskopem. / Automatization of method of surface structure measurement by means of reflection mode digital holographic microscope.Vacula, Daniel January 2010 (has links)
Reflected-light digital holographic microscope developed at IPE FME BUT uses off-axis holography principle and low spatial and temporal coherence illumination. Microscope allows reconstruction of the image amplitude and the image phase, which can be handled in real time. The only limiting factors are imaging speed of the detector and computer performance when processing holograms. Reconstruction of image phase and amplitude allows high-resolution profilometric measurements in the vertical axis direction. This thesis deals with the automatization of profilometric measurement method proposed in [2]. Proposed method uses the combination of the image phase and the image amplitude for the measurement of specimens with surface structure the vertical size of which cause the uncertainty of the image phase by a factor of 2pí. Futher the thesis deals with the construction design of the illumination system of the microscope and its realization together with experimental verification of functionality of proposed method automatization.
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Teoretický popis zobrazení digitálním holografickým mikroskopem / Theoretical description of imaging by a digital holographic microscopeSlabá, Michala January 2010 (has links)
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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Průtokové komůrky pro mikroskopii živých buněk / Flow-chambers for microscopy of living cellsČolláková, Jana January 2011 (has links)
The perfusion chamber for long term observing of live cells by the means the Coherence-Controlled Holographic Microscope (CCHM) was designed. CCHM was built and designed at the Laboratory of the optical microscopy at the Institute of Physical Engineering, Brno University of Technology. CCHM can quantitatively evaluate dynamical changes inside live cells thanks to the quantitative information about phase shift in each pixel of the image. In order to demonstrate advantages of CCHM experimentally, it is important to keep the live cells in the good conditions. This is made by adding the fresh cultivation medium for studied cells directly in the microscope. In contrast to the stationary chamber the perfusion chamber allows both the cultivation medium exchange and the application of biological reagents without the necessity of removing the chamber from the microscope. Therefore we can study the vital signs of cells before and after the application of reagents. An original perfusion system with accessories compatible with CCHM was designed. The design is based on the previously published perfusion system solutions that are referred to in this thesis. The flow characteristics and medium exchange process was discussed and a modification of the internal geometry, based on numerical simulations, was introduced. The applicability of this perfusion chamber has been proven for the CCHM and even for different types of microscopes. The reactions of tumor and epithelial cells during the change of the environment from the cultivation medium to the physiologically solution were studied.
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