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Verification of method of reconstruction of spatial distribution of refractive index by a holographic microscope
Schneider, Martin ; Antoš, Martin (referee) ; Kolman, Pavel (advisor)
Abstract The subject of the bachelor thesis is an application of transmission digital holographic microscope for verification of reconstruction of spatial distribution of the refractive index. Using eccentric pinhole as a light source is the object illuminated by a plane wave inclined to the optical axis. Different rotations of a pinhole gives us projections of the object. We have tried to reconstruct the refractive index using tomographic methods. This thesis contains design of a rotating pinhole aperture. The illumination and mounting was solved and a functionality was also proved. Experimental part deals with the reconstruction of refractive index of a tested object.
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COHERENCE-CONTROLLED HOLOGRAPHIC MICROSCOPE
Kolman, Pavel ; Křupka, Ivan (referee) ; Kozubek, Michal (referee) ; Chmelík, Radim (advisor)
ransmitted-light coherence-controlled holographic microscope (CCHM) based on an off-axis achromatic and space-invariant interferometer with a diffractive beamsplitter has been designed, constructed and tested. It is capable to image objects illuminated by light sources of arbitrary degree of temporal and spatial coherence. Off-axis image-plane hologram is recorded and the image complex amplitude (intensity and phase) is reconstructed numerically using fast Fourier transform algorithms. Phase image represents the optical path difference between the object and the reference arms caused by presence of an object. Therefore, it is a quantitative phase contrast image. Intensity image is confocal-like. Optical sectioning effect induced by an extended, spatial incoherent light source is equivalent to a conventional confocal image. CCHM is therefore capable to image objects under a diffusive layer or immersed in a turbid media. Spatial and temporal incoherence of illumination makes the optical sectioning effect stronger compared to a confocal imaging process. Object wave reconstruction from the only one recorded interference pattern ensures high resistance to vibrations and medium or ambience fluctuations. The frame rate is not limited by any component of the optical setup. Only the detector and computer speeds limit the frame rate. CCHM therefore allows observation of rapidly varying phenomena. CCHM makes the ex-post numerical refocusing possible within the coherence volume. Coherence degree of the light source in CCHM can be adapted to the object and to the required image properties. More coherent illumination provides wider range of numerical refocusing. On the other hand, a lower degree of coherence makes the optical sectioning stronger, i.e. the optical sections are thiner, it reduces coherence-noise and it makes it possible to separate the ballistic light. In addition to the ballistic light separation, CCHM enables us to separate the diffused light. Multi-colour-light
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Modifications in mechanical design of the coherence controlled holographic microscope
Matela, Milan ; Šerý, Mojmír (referee) ; Kolman, Pavel (advisor)
The aim of diploma thesis are modifications in mechanical design of the coherence controlled holographic microscope which will lead to reduction of some deficiencies. In this thesis there is a brief description of the history interference microscopy and differences between each types of interference microscopes. In this work there are stated some design deficiencies of actual condition of the microscope and also several solutions are suggested and shortly described. Then the best solution is chosen which is adjusted to a final form. It is described in detail and then realized. There is a summary included in the conclusion whether the new solution is suitable and if it fulfills the required condition.
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Applications of Fluorescence Holographic Microscope
Zobač, Evžen ; Dostál, Zbyněk (referee) ; Kolman, Pavel (advisor)
This bacherol thesis discusses the holographic fluorescence microscopy, interferometric microscope with off-axis interference. It is divided into a theoretical part and an experimental part. The theoretical part describes the setting of the holographic fluorescent microscope and basic theory of fluorescence interferometry. There are also described the methods used to increase the resolution of fluorescence microscopy. The practical part deals with the verification of the imaging properties of holographic fluorescence microscope and opportunities for enhanced imaging features and measurements.
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Possibilities of three-dimensional imaging in transmitted-light holographic microscope
Sládková, Lucia ; Jákl, Petr (referee) ; Kolman, Pavel (advisor)
Digital holographic microscopy (DHM) is noninvasive method for obtaining images even from samples with low contrast. Nowadays DHM design makes it possible to illuminate sample by broad light source, halogene lamp. Broad light source is displayed in the front focal plane of condensor in such way, that Köhler illumination is achieved. Each point of the source corresponds to a plane wave in image field of objective, which illuminates the whole field of view, but from different direction. Position of the point determines the direction of illumination. In this reason, the microscope enables so reconstruct not only intensity, but also phase of object wave. New designed and constructed interchangeable pinhole aperture modify broad light illumination by rotation around the optical axis. Aperture is placed eccentrically considering the optical axis of microscope. Incidence of light beam on a sample would be under defined angle. After the reconstruction of taken phase images from individual angles of illumination should be possible to obtain three-dimensional structure of the sample.
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COHERENCE-CONTROLLED HOLOGRAPHIC MICROSCOPE
Kolman, Pavel ; Křupka, Ivan (referee) ; Kozubek, Michal (referee) ; Chmelík, Radim (advisor)
ransmitted-light coherence-controlled holographic microscope (CCHM) based on an off-axis achromatic and space-invariant interferometer with a diffractive beamsplitter has been designed, constructed and tested. It is capable to image objects illuminated by light sources of arbitrary degree of temporal and spatial coherence. Off-axis image-plane hologram is recorded and the image complex amplitude (intensity and phase) is reconstructed numerically using fast Fourier transform algorithms. Phase image represents the optical path difference between the object and the reference arms caused by presence of an object. Therefore, it is a quantitative phase contrast image. Intensity image is confocal-like. Optical sectioning effect induced by an extended, spatial incoherent light source is equivalent to a conventional confocal image. CCHM is therefore capable to image objects under a diffusive layer or immersed in a turbid media. Spatial and temporal incoherence of illumination makes the optical sectioning effect stronger compared to a confocal imaging process. Object wave reconstruction from the only one recorded interference pattern ensures high resistance to vibrations and medium or ambience fluctuations. The frame rate is not limited by any component of the optical setup. Only the detector and computer speeds limit the frame rate. CCHM therefore allows observation of rapidly varying phenomena. CCHM makes the ex-post numerical refocusing possible within the coherence volume. Coherence degree of the light source in CCHM can be adapted to the object and to the required image properties. More coherent illumination provides wider range of numerical refocusing. On the other hand, a lower degree of coherence makes the optical sectioning stronger, i.e. the optical sections are thiner, it reduces coherence-noise and it makes it possible to separate the ballistic light. In addition to the ballistic light separation, CCHM enables us to separate the diffused light. Multi-colour-light
|
|
|
Modifications in mechanical design of the coherence controlled holographic microscope
Matela, Milan ; Šerý, Mojmír (referee) ; Kolman, Pavel (advisor)
The aim of diploma thesis are modifications in mechanical design of the coherence controlled holographic microscope which will lead to reduction of some deficiencies. In this thesis there is a brief description of the history interference microscopy and differences between each types of interference microscopes. In this work there are stated some design deficiencies of actual condition of the microscope and also several solutions are suggested and shortly described. Then the best solution is chosen which is adjusted to a final form. It is described in detail and then realized. There is a summary included in the conclusion whether the new solution is suitable and if it fulfills the required condition.
|
|
|
Possibilities of three-dimensional imaging in transmitted-light holographic microscope
Sládková, Lucia ; Jákl, Petr (referee) ; Kolman, Pavel (advisor)
Digital holographic microscopy (DHM) is noninvasive method for obtaining images even from samples with low contrast. Nowadays DHM design makes it possible to illuminate sample by broad light source, halogene lamp. Broad light source is displayed in the front focal plane of condensor in such way, that Köhler illumination is achieved. Each point of the source corresponds to a plane wave in image field of objective, which illuminates the whole field of view, but from different direction. Position of the point determines the direction of illumination. In this reason, the microscope enables so reconstruct not only intensity, but also phase of object wave. New designed and constructed interchangeable pinhole aperture modify broad light illumination by rotation around the optical axis. Aperture is placed eccentrically considering the optical axis of microscope. Incidence of light beam on a sample would be under defined angle. After the reconstruction of taken phase images from individual angles of illumination should be possible to obtain three-dimensional structure of the sample.
|
|
|
Verification of method of reconstruction of spatial distribution of refractive index by a holographic microscope
Schneider, Martin ; Antoš, Martin (referee) ; Kolman, Pavel (advisor)
Abstract The subject of the bachelor thesis is an application of transmission digital holographic microscope for verification of reconstruction of spatial distribution of the refractive index. Using eccentric pinhole as a light source is the object illuminated by a plane wave inclined to the optical axis. Different rotations of a pinhole gives us projections of the object. We have tried to reconstruct the refractive index using tomographic methods. This thesis contains design of a rotating pinhole aperture. The illumination and mounting was solved and a functionality was also proved. Experimental part deals with the reconstruction of refractive index of a tested object.
|
|
|
Applications of Fluorescence Holographic Microscope
Zobač, Evžen ; Dostál, Zbyněk (referee) ; Kolman, Pavel (advisor)
This bacherol thesis discusses the holographic fluorescence microscopy, interferometric microscope with off-axis interference. It is divided into a theoretical part and an experimental part. The theoretical part describes the setting of the holographic fluorescent microscope and basic theory of fluorescence interferometry. There are also described the methods used to increase the resolution of fluorescence microscopy. The practical part deals with the verification of the imaging properties of holographic fluorescence microscope and opportunities for enhanced imaging features and measurements.
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