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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.
1

The hologram and its antecedents, 1891-1965 : the illusory history of a three-dimensional illusion

Gamble, Susan Ann January 2005 (has links)
Since 1962, a photographic invention by Gabriel Lippmann (1845-1921), his Nobel Prize winning interference colour photograph of 1891, has been cited by physicists as the antecedent of the three-dimensional hologram. However, Dennis Gabor (1900-1979) in his original publications on the hologram of 1948 and 1949 did not cite Lippmann’s work. This thesis explores how the hologram that featured in Gabor’s original theory, as an imaging technique to improve the electron-microscope, was significantly different from the hologram for which Gabor was awarded the Nobel Prize for Physics in 1971. The citation of Lippmann’s work as the antecedent to the hologram confirmed that the hologram was to be seen as a three-dimensional photograph, and attempted to give the invention a progressive historical lineage that would conform to photography’s existing history. This popular narrative, as demonstrated in this text, could overlook the pursuit of the hologram for Cold War surveillance by researchers at the University of Michigan on behalf of the United States military. This technology was, from 1955, engaged with aerial radar image processing, a significant application that was classified and hidden from the public, and initially from Gabor himself. Two researchers at the University of Michigan, Emmett Leith (1927–) and Juris Upatnieks (1936–) attracted the attention of the popular press for their development of a three-dimensional laser hologram. This thesis reveals the fragmented nature of the new discipline at the peak of holography’s popularity. This analysis explores some of the historical traits between the two Nobel Prize winning inventions, the Lippmann photograph and the hologram, that were exploited to promote a new imaging medium to the public. In presenting these technologies as images the text also reviews devices and papers––some cited within the popular Lippmann-to Gabor historical narrative––by father and son Frederic (1856-1937) and Herbert Ives (1882-1953), that have competed to produce a three-dimensional full-colour image.
2

Conception, validation et mise en oeuvre d’une architecture de stockage de données de très haute capacité basée sur le principe de la photographie Lippmann / Conception, validation and implementation of a new architecture of high capacity optical storage based on Lippmann's photography

Contreras Villalobos, Kevin 04 February 2011 (has links)
Le stockage de données par holographie suscite un intérêt renouvelé. Il semble bien placé pour conduire à une nouvelle génération de mémoires optiques aux capacités et débits de lecture bien supérieurs à ceux des disques optiques actuels basés sur l’enregistrement dit surfacique. Dans ce travail de thèse, nous proposons une nouvelle architecture de stockage optique de données qui s’inspire du principe de la photographie interférentielle de Lippmann. Les informations y sont inscrites dans le volume du matériau d’enregistrement sous la forme de pages de données par multiplexage en longueur d’onde en exploitant la sélectivité de Bragg. Cette technique, bien que très voisine de l’holographie, n’avait jamais été envisagée pour le stockage à hautes capacités. L’objectif de la thèse a été d’analyser cette nouvelle architecture afin de déterminer les conditions pouvant conduire à de très hautes capacités. Cette analyse s’est appuyée sur un outil de simulation numérique des processus de diffraction en jeu dans cette mémoire interférentielle. Elle nous a permis de définir deux conditions sous lesquelles ces hautes capacités sont atteignables. En respectant ces conditions, nous avons conçu un démonstrateur de mémoire dit de « Lippmann » et avons ainsi démontré expérimentalement que la capacité est bien proportionnelle à l’épaisseur du matériau d’enregistrement. Avec une telle architecture, des capacités de l’ordre du Téraoctet sont attendues pour des disques de 12 cm de diamètre. / Nowadays, the holographic data storage presents a renewed interest. It seems well placed to lead a new generation of optical storage capacity and playback speeds much higher than current optical discs based on the recording onto a surface. In this thesis, we propose a new architecture for optical data storage that is based on the principle of Lippmann photography interferential. Information are included in the volume of the recording material in the form of pages of data multiplexing in wavelength by exploiting the Bragg selectivity. This technique, although very similar to holography, had never been considered for high storage capacities. The aim of the thesis was to analyze this new architecture to determine the conditions that can lead to very high capacities. This analysis was based on a numerical simulation tool of diffraction process involved in this memory interferential. It allowed us to define two conditions under which these high capacities are achievable. In accordance with these conditions, we developed a demonstrator called "Lippmann’s memory" and have thus demonstrated experimentally that the capacity is proportional to the thickness of the recording material. With such an architecture, Terabyte disks of 12 cm in diameter are expected.

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