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1	Studium sférické vady optické čočky / Study of spherical aberration Fojtík, Tomáš January 2013 (has links) This thesis deals with the theoretical analysis of rays passing through lenses. Emphasis on optical defects, particularly focusing on spherical aberration lenses. It also includes the preparation of a workplace and the measurement of spherical aberration and evaluate the quality of different lenses. Furthermore, a program for simulation of spherical aberration lens.
2	Miscibility and Structure-Property Relationships in Some Novel Polyolefins Kamdar, Akshay R. 12 February 2009 (has links) No description available. Engineering Plastics Polymers polyolefins copolymers polypropylene polyethylene adhesion gradient refractive index optical lens
3	Koncept moderního LED svítidla pro osvětlení pozemních komunikací / Modern LED luminaire concept for road lighting Krejčí, Miroslav January 2018 (has links) This thesis deals with design of optical system for road lighting luminaire. In the beginning the basic photometric quantities and assessment methodology for requirements of lighting class M are described. The next step is the programming of algorithm which evaluates the road lighting requirements using few boundary conditions. The input of the algorithm is also luminous intensity (power emitted in a particular direction). By the turning the algorithm over, it is possible to evaluate the luminous intensity from the road lighting requirements. Those luminous intensities are used in the process of modification of optical lens. The ray tracing of modified models of lenses was performed to obtain the tables of luminous intensity. The values of luminous intensity are verified in the same algorithm. Finally, the comparison of results was made including several luminaires out there.
4	Měření parametrů optických čoček / Measurement of optical lenses parameters Wintr, Aleš January 2011 (has links) This paper contains a basic overview and description of optical lenses. It introduces different types of optical lenses and shows how they influence the passing of light beams. It deals with the production of optical lenses and their practical use. It describes types of optical blemishes that exist in real optical systems. Particular attention is given to parameters of optical lenses and their measurement in practice. It includes a Matlab program to calculate parameters of optical lenses derived from the measurements.
5	Detekce živosti prstu na základě změn papilárních linií / Liveness Detection of a Finger Based on Changes of Papillary Lines Lichvár, Michal January 2008 (has links) There are several frauds against biometric systems (BSs) and several techniques exist to secure BSs against these frauds. One of the techniques is liveness detection. To fool fingerprint sensors, latent fingerprints, dummy fingers and wafer-thin layer attached to the finger are being used. Liveness detection is being used also when scanning fingerprints. Several different characteristics of the live finger can be used to detect liveness, for example sweat, conductivity etc. In this thesis, new approach is examined. It is based on the expandability of the finger as an effect of heartbeats/pulsation. As the skin is expanding, also the distances between papillary lines are expanding. Whole finger expands approximately in range of 4,5 ľm , the distance between two neighbor papillary lines in 0,454 ľm . This value collides with wavelength of blue and green light. The result from this work is following. The resolution of the capturing device is not high enough to capture the expandability on distance between two neighbor papillary lines. Also, because of collision with wavelength, the diffraction effect is presented and the result images are influenced by this error.
6	Modélisation et caractérisation de réseaux holographiques ; étude de composants optiques holographiques en gélatine bichromatée Chateau, Nicolas 21 July 1993 (has links) (PDF) Dans les systèmes optiques modernes, l'importance des composants holographiques ne cesse d'augmenter. Parmi les matériaux holographiques disponibles, la gélatine bichromatée se distingue par la très bonne qualité des hologrammes obtenus. Cette thèse décrit la mise au point de techniques de fabrication et de caractérisation de composants holographiques en gélatine bichromatée. L'interprétation des mesures de caractérisation s'appuie sur une modélisation approfondie de la diffraction par des structures périodiques: une nouvelle méthode de résolution de la théorie d'ondes couplées, plus stable numériquement que les précédentes, est proposée. De plus, la théorie de la diffraction par des réseaux est étendue a des cas importants de restitution en lumière quasi-monochromatique. Les dispositifs expérimentaux développés ont permis l'étude et la réalisation de quatre nouveaux types d'hologrammes: réseaux pour la compression temporelle d'impulsions ultra brèves, hologramme synthétique séparateur et uniformiseur de faisceau laser, lentille holographique pour diode laser infrarouge et hologramme en ligne pour la réplication globale de disques compacts. holographie gelatine bichromatee fabrication caracterisation compression impulsion hologramme diode laser lentille optique disque compact uniformisation faisceau separateur faisceau onde couplée pac element optique holographique cd diffraction gratings holography bichromated gel characterization pulses holograms laser diodes optical lens compact disk beam shaping beam separators holographic optical element cd

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