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Koherencí řízený holografický mikroskop s digitální optikou / Coherence Controlled Holographic Microscope with the digital opticsVavřinová, Jana January 2018 (has links)
The Digital Micromirror Device (DMD) technology has been developed especially for Digital Light Processing projectors, which allow the image projection. After this succesful implementation, and thanks to the commercial availibility and low initial cost of the DMD chip, a wide range of other applications became possible. Besides, it may be used in microscopy as a spatial light modulator. For example in Coherence-Controlled Holographic Microscope (CCHM) that finds its use especially for imaging and measurement of live-cell dynamic processes. The DMD chip placed in the illumination part of CCHM allows for broadening the application possibilities. Namely it could be different illumination mode experiments or tomographic applications. The master's thesis deals with the optical design of CCHM with digital optics, i. e. DMD chip. The selection of optical elements for CCHM, the experimental verification of the imaging setup and the process of designing the illumination part are described in detail. In the end, the analysis of different designs for illumination setup with the digital optics in object arm is carried out and the results are compared.
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Snižování tření mazaných kontaktů změnou tepelné vodivosti materiálů / Improving friction of lubricated contacts by modifying thermal conductivityŠnevajs, Matěj January 2019 (has links)
This thesis deals with an experimental study regarding the effects of the thermal conductivity of contact bodies on the friction, lubricant film thickness and temperature distribution in EHL contact. The thesis focuses on the configuration of the ball on disc contact. The contact body materials are characterized by a wide range of thermal properties. New contact pairs are proposed and used in the study in order to make the contact bodies’ thermal properties dependent on the behaviour of EHL contact. The colorimetric interferometry method is used to measure the lubricant film thickness and the infrared thermography method is used to observe the temperature distribution in EHL contact. The author presents the assumed mechanism of heat transfer within EHL contact on the basis of different heat transfer mechanisms. The same conditions – such as the Hertz pressure, mean entrainment speed, sliding speed and ambient temperature – are induced for all the contact pair combinations. That is why the differences in the results are attributed to the different thermal phenomena in the contact, caused by the thermal properties of the contact bodies. In the case of contact bodies with a reduced heat dissipation capability, a reduction of the friction coefficient of up to 50 % is observed, which is attributed to an increase in the lubricant temperature, resulting in a decrease in its viscosity. This is confirmed by the infrared thermography method, whereby a significantly higher lubricant temperature is observed in the case of a combination of contact materials with a lower heat dissipation capability.
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Vláknový osvětlovací modul pro mikroskopii / Fiber guided illumination moduleKropáč, Vlastimil January 2020 (has links)
This diploma thesis describes the design of the illumination system for a Coherence--Controlled Holographic Microscope (CCHM). The theoretical part mentions the history of microscopy, the principle of holography and individual types of interference microscopy. To get closer to the topic, individual light sources and an overview of current illumination systems are mentioned. The diploma thesis also describes the procedure of designing a fiber-optic illumination module for microscopy from optical design through design of construction to the last step, which is assembly and testing of the module.
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Mapování tloušťky mazacího filmu u náhrad velkých kloubů člověka / Mapping of lubricating film thickness of human big joints replacementsBosák, Dalibor January 2012 (has links)
This master’s thesis describes mechanism of lubricating film forming and its thickness in contact of a metal hip joint ball and a glass disc with chromium layer with presence of bovine serum as substitute of synovial fluid occured in a natural joint. Lubricating film thickness is evaluated by a thin film colorimetric interferometry, results are ploted at graphs representing dependence of lubricating film thickness on experiment duration or on mutual speed of articulating surfaces. There is described the influence of concentration of bovine serum and different kinematic conditions on lubricating film forming. From observed interferograms is apparent the adsorption of proteins to glass disc and femoral head surfaces, denaturation and formation of protein aggregations affecting the residual lubricating film thickness.
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Zařízení pro měření vlnoplochy mikroskopových objektivů / Device for wavefront measurement of microscope objective lensesBartoníček, Jan January 2013 (has links)
The wavefront reconstruction of a light wave transformed by a microscope objective is the main subject of this diploma thesis together with the design and assembly of a~measuring device and the development of a computational algorithm. The purpose is to determine optical aberrations and to compare a quality of objectives with identical parameters. The term wavefront is explained and its description using Zernike polynomials is introduced in the first part of the thesis. The following part summarizes possible methods for wavefront reconstrucion. Two methods were chosen for experimental determination of a wavefront shape – shearing interferometry and solution of the transport of intensity equation. For each method a brief characteristic is provided together with possible applications, mathematical apparatus, image processing, computational procedure, setup description and proposition and results of experiments. The suitability of both methods for optical aberration determination and microscope objective comparison is discussed. Based on the obtained results, both methods were found to be suitable for comparison of microscope objectives. The suitability for optical aberration determination is possible with certain restrictions.
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Experimentální studium mazání okolku kolejových vozidel / Experimental Study of Wheel Flange LubricationFrýza, Josef January 2013 (has links)
This diploma thesis deals with the experimental study of the influence of operating conditions on the tribological aspects of the wheel flange and rail gauge contact. The wheel flange contact occurs when the vehicle moves on a curve track and it leads to severe up to catastrophic wear regime. For effective reduction of wear is important to apply a suitable amount of lubricant at appropriate intervals into the contact. The issue in this work comprehensively studies using of three laboratory apparatus and six methods that are theoretically and experimentally compared. Assessed are friction, wear, distribution and film thickness of lubricants for different contact conditions. The resulted amount of lubricant and interval of its application eliminates development of seizure at low consumption of lubricant. The understanding of mechanisms that occur in the wheel-rail contact not only helps to reduce operating costs and improved to energy efficiency of movement of vehicle on a track, but it is the basis for safe, reliable and ecological operation of rail transport.
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Experimentální studium tření a mazání TEP kyčle / Experimental study of friction and lubrication in THRUrban, Filip January 2014 (has links)
This work analyzes problems of friction and lubrication of total hip replacement (THR). At first, experimental study of friction coefficient under various conditions was conducted using hip joint simulator based on principle of pendulum. After that, lubrication film development was observed, using colorimetric interferometry with head from THR and glass cup with respect of geometry and clearance to cups made originally for THR. With respect to research study [25] it was found that increasing contact conformity leads to increased film thickness. Also protein adsorption on articulating surfaces was observed. Thanks to adsorption 80 nm film thickness was measured even if relative surface speed was zero. Furthermore protein aggregation was observed on the border of contact zone, similar aggregations were observed by Myant et al. [29] or Vrbka et al. [25]. These aggregations are formed when lubricant is under shear stress and it can positively affect film thickness. If the relative motion of articulating surfaces is not sufficient, the protein layer can`t be refreshed enough and film thickness start decreasing. Coefficient of friction 0,13 was measured when lubricating film development was observed. Close to this value are material combinations metal on polyethylene and metal on metal.
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Měření parametrů textury povrchu výrobků kontaktní a bezkontaktní metodou / Measurement of Surface Texture Parameters of Products Using Contact and Non-contact MethodsHarčarík, Matej January 2016 (has links)
This master’s thesis includes an overview of profile method of surface texture evaluation according to ISO standards and VDA automotive standards, as well as an overview of areal method according to ISO 25178 standard series, which includes a proposal for improvement of czech terminology. Suitability of application of selected measurement methods for measurement of a portfolio of automotive parts was evaluated based on measurements carried out using a contact profiler, a coherence scanning interferometer and a confocal microscope. Further recommendations for practice in surface texture metrology were also formulated. A regression analysis of the relationship between values of selected profile surface texture parameters and their areal equivalents was also performed. Its results may aid the spread of areal surface texture evaluation in the industry.
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Konstrukce odměřovacího systému pro systém reaktivního iontového leptání / Mechanical design of measurement system for reactive ion etching systemMaňka, Tadeáš January 2016 (has links)
The aim of this work is to design fully working measuring system for the reactive ion etching system (RIE). The Michelson interfometer, previously developed in Ústav přístrojové techniky, v.v.i., is used in this work. The theoretical part is aimed at description of interferometric methods for precise measuring of length. In next part the etching proces with RIE is described. In practical part the testing system was constructed from the parts of Thorlabs company . The functionality was controlled with this system and the results of measuring were compared with the profilometer. In next step technical drawings were created and the whole system was made.
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The Effect of Synovial Fluid Constituents on Lubrication of Hip Joint Replacements / The Effect of Synovial Fluid Constituents on Lubrication of Hip Joint ReplacementsNečas, David January 2016 (has links)
Dizertační práce se zabývá mechanismy mazání v náhradách kyčelního kloubu. Byla provedena systematická studie formování proteinového filmu při zahrnutí různých materiálů a provozních podmínek. Hlavní pozornost je přitom věnována roli jednotlivých proteinů obsažených v synoviální kapalině při současné přítomnosti dalších proteinů. Jelikož metody aplikované v předchozích studiích neumožňovaly separovat jednotlivé složky maziva, byla vyvinuta optická měřící metoda na principu fluorescenční mikroskopie. Z důvodu verifikace metody byly provedeny dvě nezávislé studie zaměřené na měření tloušťky mazacího filmu a dělení maziva na výstupu mazaného kontaktu. Z důvodu určitých limitací fluorescenční mikroskopie byla dále využita i metoda optické interferometrie, jejíž využití je ilustrováno ve studii zabývající se formováním mazacího filmu v náhradách kyčelního klubu při uvažování reálné konformity třecích povrchů. Závěrečná část práce představuje nový metodologický přístup založený na in situ pozorování kontaktní oblasti umožňující popsat roli jednotlivých proteinů ve vztahu k vývoji tloušťky mazacího filmu. Práce obsahuje originální výsledky, které přináší nové poznání v oblasti biotribologie náhrad kyčelního kloubu vedoucí k dalšímu vývoji implantátů při snaze zabránit jejich selhání v důsledku omezené životnosti.
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