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1	Evaluation of a Holographic 3D Display Björk, Jim January 2010 (has links) An autostereoscopic display based on a Holographic Optical Element(HOE) presents new opportunities for faithful 3D displaying but also presents potential new problems, such as: accuracy of 3D objects, interactivity and user perception. In this evaluation, which is the first of its kind for this type of display, I have explored and tested methods and tools for the evaluation of these potential problems. I have found that the visual quality is comparable to more common display types but with a significant visual delay due to the parallel rendering of graphics and the projectors significant input lag. From this I have concluded that the display system is not yet ready for its intended purpose, cranio-maxillofacial surgery planning. We need projectors with less input lag and preferably better optics. The software needs to be optimized for multimonitor rendering as well. Autostereoscopic display Holographic Optical Element Evaluation
2	An automatic holographic adaptive phoropter Peyman, Gholam A., Schwiegerling, Jim, Amirsolaimani, Babak, Bablumyan, Arkady, Savidis, Nickolaos, Peyghambarian, Nasser N. 29 August 2017 (has links) Phoropters are the most common instrument used to detect refractive errors. During a refractive exam, lenses are flipped in front of the patient who looks at the eye chart and tries to read the symbols. The procedure is fully dependent on the cooperation of the patient to read the eye chart, provides only a subjective measurement of visual acuity, and can at best provide a rough estimate of the patient's vision. Phoropters are difficult to use for mass screenings requiring a skilled examiner, and it is hard to screen young children and the elderly etc. We have developed a simplified, lightweight automatic phoropter that can measure the optical error of the eye objectively without requiring the patient's input. The automatic holographic adaptive phoropter is based on a Shack-Hartmann wave front sensor and three computer-controlled fluidic lenses. The fluidic lens system is designed to be able to provide power and astigmatic corrections over a large range of corrections without the need for verbal feedback from the patient in less than 20 seconds. Phoropter Fluidic lens Holographic Optical Element
3	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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