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  • About
  • The Global ETD Search service is a free service for researchers to find electronic theses and dissertations. This service is provided by the Networked Digital Library of Theses and Dissertations.
    Our metadata is collected from universities around the world. If you manage a university/consortium/country archive and want to be added, details can be found on the NDLTD website.
11

Ir.M.A. - Klinický přístroj pro měření dynamiky akomodace a vergence / Ir.M.A. - Infrared Measurement and Analysis of Accommodation and Vergency

Jindra, Tomáš January 2011 (has links)
This work is dealing with design of the systém for measuring dynamics of the vergence and accommodation. Vergence accommodation synkinesis is a complex process controlled by various mechanisms in CNS. Deviations from physiological state of the vision process are projected to course of the vergence accommodation curves and is possible the quantitative and qualitative evaluation. For this purpose was designed the measuring system Ir.M.A. (Infrared Measurement of Accommodation). The system uses high-speed videometric device for determination of the relative vergence and relative accomodation of the eyes. Stimulation of the patient's eyes is performed by the standardized jump change of the fixation object distance. The object is reconstruted by holographic method. Measured videosequences are processed by the image analysis. Results of the image analysis are courses of the vergence and accommodation curves depending on time and characteristics of the curves. System is designed for using in clinical practice where it could be used as screening instrument for diagnostics of the oculomotor system disorders.
12

Rekonstrukční metody v holografické mikroskopii / Reconstruction methods in holographic microscopy

Findejsová, 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.
13

Fázové zobrazování pod difrakčním limitem / Phase imaging below the diffraction limit

Nečesal, Daniel January 2020 (has links)
Tato diplomová práce se zabývá konstrukcí interferenčních zařízení pro výzkum měření fáze světla na mikro-strukturách a fáze plazmonů na nano-strukturách. V první kapitole je vybudován teoretický základ pro optiku a nano-fotoniku používané v budoucích kapitolách. Následně je popsána interference vln a jejich praktické použití pro prolomení difrakčního limitu pomocí holografie plazmonů. Prvním experimentální sestavou je Machův-Zehnderův holografický mikroskop. Je popsán způsob, jak ho sestavit z běžně dostupných součástek a jak je navržen ovládací software k jeho používání. Následně jsou popsány výsledky naměřené pomocí tohoto zařízení. V poslední kapitole se zaměříme na sestavení holografického SNOM přístroje pro studování plazmonů a jejich interference. Nejdříve popíšeme základní princip a navržení softwaru pro automatizaci měření, pro zrychlení vědeckých postupů. Nakonec předložíme výsledky měření mikroskopu.
14

Justážní kolimátor pro Fluorescenční holografický mikroskop / The adjusting collimator for the Fluorescent holographic microscope

Hlaváčová, Kateřina January 2018 (has links)
For the proper function of the Fluorescence olographic microscope, it is necessary to adjust all the optical components of the microscope. Furthermore, the precise adjustment is the very critical condition for proper imaging of the Coherence-controlled holographic microscope. Therefore, it is necessary to create a sight collimator for these microscopes for their adjustment. The fluorescence holographic microscope is based on an interference and holographic principles, whose history is mentioned in the theoretical part of the thesis. The existing state of the art of laser sight collimators and their use in practice is also mentioned. The optical and mechanical design of the laser sight collimator and its realization are described in the next part of the thesis. The software for detecting the black sight cross was created for the use of the laser sight collimator in practice. The software is necessary to evaluate the correctness of the alignment of the adjusted microscope. The descriptions of the adjustment procedures for the laser sight collimator and for the Fluorescence holographic microscope are mentioned in the last part of the thesis. These procedures are necessary for proper manipulation and use with the proposed laser sight collimator.
15

Vláknový osvětlovací modul pro mikroskopii / Fiber guided illumination module

Kropáč, 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.
16

Fresnelova nekoherentní korelační holografie (FINCH) / Fresnel Incoherent Correlation Holography (FINCH)

Bouchal, Petr January 2012 (has links)
This master’s thesis develops a novel method of digital holography, from recent studies known as Fresnel Incoherent Correlation Holography (FINCH). The method enables the reconstruction of the correlation records of three-dimensional objects, captured under quasi-monochromatic, incoherent illumination. The experimental system is based on an action of a Spatial Light Modulator, driven by computer generated holograms to create mutually correlated beams. Both optical and digital parts of the experiment can be carried out using procedures of classical holography, diffractive optics and digital holography. As an important theoretical result of the master’s thesis, a new computational model was proposed, which allows to describe the experiment completely with respect to its two basic phases. The proposed model allows to understood the method intuitively and can be used additionally for analysis and interpretation of the imaging parameters and the system optimalization. The theoretical part of the master’s thesis also presents a detailed description of the correlation imaging based on an appropriate reconstruction process. Computational models were developed for both monochromatic and quasi-monochromatic illumination. In experimental part, all theoretical results were verified. The imaging parameters were examined using standard resolution target tests and appropriate biological samples. As an original experimental result, spiral modification of the system resulting in a vortex imaging was proposed and realized. Here, a selective edge enhancement of three-dimensional objects is possible, resulting in a significant extension of possible applications of the method.
17

Akustická diagnostika strojů / Acoustic diagnostics of machines

Gajdoš, Petr January 2012 (has links)
The aim of this master´s thesis is to work out a comparison and evaluation of selected methods used for sound field mapping. Thesis will include software tools and results of sample measurement on test object for each mapping method.
18

Koherencí řízený holografický mikroskop nové generace / New Generation of a Coherence-Controlled Holographic Microscope

Slabý, Tomáš January 2015 (has links)
This doctoral thesis deals with design of a new generation of coherence-controlled holographic microscope (CCHM). The microscope is based on off-axis holographic configuration using diffraction grating and allows the use of temporally and spatially incoherent illumination. In the theoretical section a new optical configuration of the microscope is proposed and conditions for different parameters of the microscope and its optical components are derived. The influence of different sources of noise on phase detection sensitivity is studied. In the next section design of experimental setup is described and automatable adjustment procedure is proposed. Last section describes experimental verification of the most important optical parameters of the experimental setup. When compared to previous generation of CCHM, the newly proposed configuration uses infinity-corrected objectives and common microscope condensers, allows more space for the specimens, eliminates the limitation of spectral transmittance and significantly simplifies the adjustment procedure so that automation of this procedure is possible.
19

Počítačem generované hologramy / Computer Generated Holograms

Tvarog, Drahoslav January 2010 (has links)
The presented Diploma thesis deals with the computer-generated diffractive structures or rather called computer generated holograms (CGH). We follow basic principles of classical holography and in the context of which we define a synthetic holography. We then show various types of digital holograms and methods of measurement of their quality. We deal with several iterative algorithms useful for computation of the Fourier transform as well as with methods of phase quantization. In the second part of the work, we describe briefly our computer code for iterative Fourier transform computation. With respect to the mentioned techniques, we further present the usability of the method for design of computer generated holograms in reflection regime. After a short introduction to the electron beam lithography and its exploitation for the origination of computer generated diffractive optical elements. We analyze reconstructions of produced holograms and evaluate its quality.
20

Návrh specielního měřicího zařízení pro kontrolu sražení hran / The proposal of a special measuring device to check the chamfer

Novotný, Jan January 2014 (has links)
This diploma thesis consist of basic overview of contact and non-contact measuring methods used at present days across industrial Applications. On the base of given specification for designing of measuring station for measuring chamfer of rotary components The choice and evaluation of theoretical applicability for our application is performed. In the practical part of this diploma thesis The applicability is verified. Performance of these a few exemplary measuring shows possible way of design of constructional solution. All this in a close cooperation with company MESING.

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