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Image analysis for correction of electron microscopes
Smital, Petr ; Schwarz, Daniel (referee) ; Kolář, Radim (advisor)
This thesis describes the physical nature of corrections of an electron microscope and mathematical methods of image processing required for their complete automation. The corrections include different types of focusing, astigmatism correction, electron beam centring, and image stabilisation. The mathematical methods described in this thesis include various methods of measuring focus and astigmatism, with and without using the Fourier transform, edge detection, histogram operations, and image registration, i.e. detection of spatial transformations in images. This thesis includes detailed descriptions of the mathematical methods, their evaluation using an “offline” application, descriptions of the algorithms of their implementation into an actual electron microscope and results of their testing on the actual electron microscope, in the form of a video footage grabbed from its control computer’s screen.
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Tolerances and Misalignment Aberrations for Electron Optical Elements and Systems
Sháněl, Ondřej ; Radlička, Tomáš (referee) ; Tiemeijer,, Peter Christiaan (referee) ; Zlámal, Jakub (advisor)
Nepřesnosti při výrobě a sestavení rotačně souměrné čočky a deflektrou a jejich přesného zařazení do elektronově optického systému se projeví jako dodatečné pole příslušné symetrie, které deformuje ideální zobrazení. Tato dodatečná pole dokážeme spočítat pomocí metody konečných prvků v programu EOD. Toleranční analýza spočívá ve stanovení požadavků na rozměry a sestavení jednotlivých prvků a jejich částí. Korekce vad seřízení pak spočívá v určení typu a polohy korekčních vychylovacích cívek a multipólů tak, aby se tyto dodatečné vady odstranily, nebo aby se minimalizoval jejich vliv. Cílem disertační práce je analýza projevů vad seřízení a chování neseřízených systémů prozařovacích elektronových mikroskopů.
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Electrostatic Deflection and Correction Systems
Badin, Viktor ; Oral, Martin (referee) ; Zlámal, Jakub (advisor)
The aim of this master's thesis is to explore and study dynamic aberration correction options in electron-beam lithography systems. For the calculations, the thesis uses the optical column of the BS600 electron-beam writer. The thesis focuses on corrections of the third order field curvature, astigmatism, and distortion aberrations of the currently used magnetic deflection system and a newly designed electrostatic deflection system. The parameters of the two deflection and correction systems were compared.
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The Telescopes of Dall-Kirkham
Rail, Zdeněk ; Ulrichová, Iva ; Kuryshev, V. ; Vápenka, David
The paper deals with the optical aberrations of the two-mirror telescopes composed of the ellipsoidal primary and the spherical secondary mirrors. The system was discovered by Horace Dall and Alan Kirkham at the end of the Twenties of the 20th Century. Its optical elements are easy to manufacture and measure. These telescopes can be equipped by lens correctors and turned into multipurpose devices both for planetary observation and wide field photography. Several telescopes were manufactured in workshop of the Toptec Center in Turnov.
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The Catadioptric System of G.M. Popov of the Observatory of Úpice
Rail, Zdeněk ; Melich, Zbyněk
During the Sixties of the Twentieth Century series of two-mirror catadioptric telescopes were designed with a correcting lens in front of their secondary mirror. One of the first designers of these devices was P.P. Argunov. His optical designs were further developed by G.M. Popov, J. Klevcov and other opticians. In 2005 one telescope of a Popov system of diameter 305 mm was manufactured in the Development Optical Workshop of Academy of Sciences of Czech Republic /now Institute of Plasma Physics of AS CR,v.v.i.-Toptec/ in Turnov. The telescope was intended to substitute an older Maksutov-Cassegrain telescope of diameter of 260 mm of the Observatory in Úpice which required the reconstruction. In this paper we present an optical design of the Popov´s system of the Observatory in Úpice and compare it with an equal commercial Schmidt-Cassegrain telescope and further devices.\n
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Tolerances and Misalignment Aberrations for Electron Optical Elements and Systems
Sháněl, Ondřej ; Radlička, Tomáš (referee) ; Tiemeijer,, Peter Christiaan (referee) ; Zlámal, Jakub (advisor)
Nepřesnosti při výrobě a sestavení rotačně souměrné čočky a deflektrou a jejich přesného zařazení do elektronově optického systému se projeví jako dodatečné pole příslušné symetrie, které deformuje ideální zobrazení. Tato dodatečná pole dokážeme spočítat pomocí metody konečných prvků v programu EOD. Toleranční analýza spočívá ve stanovení požadavků na rozměry a sestavení jednotlivých prvků a jejich částí. Korekce vad seřízení pak spočívá v určení typu a polohy korekčních vychylovacích cívek a multipólů tak, aby se tyto dodatečné vady odstranily, nebo aby se minimalizoval jejich vliv. Cílem disertační práce je analýza projevů vad seřízení a chování neseřízených systémů prozařovacích elektronových mikroskopů.
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Electrostatic Deflection and Correction Systems
Badin, Viktor ; Oral, Martin (referee) ; Zlámal, Jakub (advisor)
The aim of this master's thesis is to explore and study dynamic aberration correction options in electron-beam lithography systems. For the calculations, the thesis uses the optical column of the BS600 electron-beam writer. The thesis focuses on corrections of the third order field curvature, astigmatism, and distortion aberrations of the currently used magnetic deflection system and a newly designed electrostatic deflection system. The parameters of the two deflection and correction systems were compared.
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Image analysis for correction of electron microscopes
Smital, Petr ; Schwarz, Daniel (referee) ; Kolář, Radim (advisor)
This thesis describes the physical nature of corrections of an electron microscope and mathematical methods of image processing required for their complete automation. The corrections include different types of focusing, astigmatism correction, electron beam centring, and image stabilisation. The mathematical methods described in this thesis include various methods of measuring focus and astigmatism, with and without using the Fourier transform, edge detection, histogram operations, and image registration, i.e. detection of spatial transformations in images. This thesis includes detailed descriptions of the mathematical methods, their evaluation using an “offline” application, descriptions of the algorithms of their implementation into an actual electron microscope and results of their testing on the actual electron microscope, in the form of a video footage grabbed from its control computer’s screen.
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