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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.
81

Gauge theory, holography and strongly coupled physics

Blake, Michael Andrew January 2014 (has links)
No description available.
82

Subwavelength Focusing via Holographic Metallic Screens

Wong, Alex Man Hon 22 September 2009 (has links)
In this work we investigated a new class of subwavelength focusing device, termed the holographic metallic screen. We first proposed a generalized procedure which takes a holographic record of a subwavelength electromagnetic field distribution. Subsequently we synthesized this record using two types of holographic metallic screen – the slot antenna hologram (SAH) and the resonant slot antenna hologram (RSAH). We designed both holograms and evaluated their performances through full-wave simulations, and experimentally demonstrated subwavelength focusing for the RSAH. Simulations and experiments illustrated various attractive properties of the subwavelength focusing RSAH, which included (a) a tighter focal width than a single subwavelength aperture; (b) a focal field amplitude surpassing the incident field amplitude; and (c) a simple design scalable to a wide range of frequencies from microwave to optical. These properties should serve to motivate further development on the holographic metallic screen towards potential applications such as sensing, imaging and lithography.
83

Subwavelength Focusing via Holographic Metallic Screens

Wong, Alex Man Hon 22 September 2009 (has links)
In this work we investigated a new class of subwavelength focusing device, termed the holographic metallic screen. We first proposed a generalized procedure which takes a holographic record of a subwavelength electromagnetic field distribution. Subsequently we synthesized this record using two types of holographic metallic screen – the slot antenna hologram (SAH) and the resonant slot antenna hologram (RSAH). We designed both holograms and evaluated their performances through full-wave simulations, and experimentally demonstrated subwavelength focusing for the RSAH. Simulations and experiments illustrated various attractive properties of the subwavelength focusing RSAH, which included (a) a tighter focal width than a single subwavelength aperture; (b) a focal field amplitude surpassing the incident field amplitude; and (c) a simple design scalable to a wide range of frequencies from microwave to optical. These properties should serve to motivate further development on the holographic metallic screen towards potential applications such as sensing, imaging and lithography.
84

Holography and inflation in low dimensions /

Cunha, Bruno Geraldo Carneiro da. January 2003 (has links)
Thesis (Ph. D.)--University of Chicago, Department of Physics, August, 2003. / Includes bibliographical references. Also available on the Internet.
85

Frequency Domain Holography of laser wakefields

Matlis, Nicholas Hill 28 August 2008 (has links)
Not available / text
86

Dynamic holographic masks for adaptive optical lithography

Bay, Christoph January 2012 (has links)
No description available.
87

Angular addressing properties of volume Fourier transform holograms in iron-doped lithium niobate

Weaver, John Elbert 05 1900 (has links)
No description available.
88

Evaluation of volume holographic optical elements in dichromated gelatin

Blair, Loudon Thomas January 1989 (has links)
The use of dichromated gelatin (DCG) for the formation of holographic optical elements is investigated. In particular, a study is made of the possible sources of spurious recording and replay in such diffracting media. The formation of spurious gratings due to boundary mismatch, when recording a transmission grating in air, is investigated. Experimental results are treated using a simple linear theory which is capable of predicting the relative modulation strengths of each of six recorded gratings. The efficiencies of each of these gratings is related to Fresnel's Laws of reflection and therefore the beam ratio. A brief experimental study of the beam ratio is made. It is found that linear theories do not explain replay of gratings recorded at high exposure energies. This is because DCG exhibits a saturating recording characteristic. A theoretical model is developed to verify experimental results of modulation versus exposure energy for the recording of single and double exposure transmission gratings and their subsequent harmonics. This gives good agreement for most cases, however, it does not explain fully the replay of a difference grating formed due to nonlinearities in the double exposure hologram. A coupled wave theory is therefore developed to take account of both multiple grating interactions between the two primary recordings and the recording of a third grating with a spatial frequency equal to the difference of the two fundamental frequencies. The model gives good agreement with experimental results for varying replay angles and wavelengths. DCG is finally used as a tool to investigate the formation of noise gratings in silver halide emulsions. In particular, results are presented for experiments which were performed to study the effect of high angular scatter upon the selectivity of the noise grating and the recording of reflection noise gratings.
89

Design and fabrication of surface relief diffractive optical elements, or kinoforms, with examples for optical athermalization /

Londoño, Carmiña. January 1900 (has links)
Thesis (Ph.D.)--Tufts University, 1992. / Submitted to the Dept. of Electrical Engineering and Electro-Optics Technology Center. Adviser: Robert Gonsalves. Includes bibliographical references (leaves 195-206). Access restricted to members of the Tufts University community. Also available via the World Wide Web;
90

Ultra-compact holographic spectrometers for diffuse source spectroscopy

Hsieh, Chaoray. January 2008 (has links)
Thesis (Ph. D.)--Electrical and Computer Engineering, Georgia Institute of Technology, 2008. / Committee Chair: Adibi, Ali; Committee Member: Chang, Gee-Kung; Committee Member: Ralph, Stephen; Committee Member: Trebino, Rick; Committee Member: Verriest, Erik I.

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