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Showing 1 to 11 of 11 for “"Luneburg"”.
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Design of a photonic crystal planar Luneburg lens for optical beam steering
… view (FOV). Here I present a design for a planar Luneburg lens for use in a silicon photonics optical beam steering device fabricated using CMOS-compatible techniques. The gradient index of the lens is achieved using a photonic crystal consisting of amorphous silicon patterned with a triangular …
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Multi-beam Antenna Arrays for Base Stations in Cellular Communication Systems
… for implementing multi-beam antenna such as Luneburg lenses should be an attractive alternative. In this thesis, some of the advantages and limitations of these opposing technologies using as examples firstly, a multi-beam antenna implemented using a Butler matrix feed network which is …
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Design and fabrication of micro- and nano- dielectric structures for imaging and focusing at optical frequencies
… frequencies. Structures such as rod lenses and Luneburg lenses are investigated. Especially the latter type of lenses have been conventionally difficult to implement in optical frequencies due to its specific refractive index profile. With the high flexibility of gradient effective index design …
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Locally finite near-fields
… order, pln, and the order of centres, pl, and Luneburg has determined the number of isomorphism types within each class. A polynomial h is given here which, together with the triple p, l, n, completely determines a finite regular near-field, up to isomorphism. The sub-near-field structure is …
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Locally finite near-fields
… order, pln, and the order of centres, pl, and Luneburg has determined the number of isomorphism types within each class. A polynomial h is given here which, together with the triple p, l, n, completely determines a finite regular near-field, up to isomorphism. The sub-near-field structure is …
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Fabrication of anti-reflective and imaging nanostructured optical elements
… an all-dielectric subwavelength-patterned Luneburg lens was fabricated for operation at free-space wavelength of A =1.55 um.
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On-Chip Planar Lens Architectures for Optical Beam Steering
… The second experimental demonstration is a Luneburg lens that is designed with a gradient in the refractive index along the radius of the lens. This second system uses a circularly symmetric grating to emit the optical beam over a wide field of view. Both planar lens architectures leverage a …
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Public Buildings and Civic Pride: Town Halls in Northern Germany, 1200--1618
… major communal structures in Lubeck, Bremen and Luneburg, all of which are distinguished by their complex architectural histories, in each case lasting for several centuries. These three town halls represent part of a wide-ranging phenomenon in the history of German communal architecture, in …
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Realization of a 3D gradient index medium in porous silicon
… GRIN lenses including the world’s smallest known Luneburg lens, 3D subsurface optical waveguides, and even 3D, multiplanar nanophotonic elements, and complex diffractive optics. This work paves a new path for designing novel subsurface optical elements with future applications in imaging and point …
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Advances in Complex Electromagnetic Media
… design based on spherical symmetry, such as a Luneburg lens, and warp it to suit the requirements of a planar imaging array. I report on the experimental demonstration of this lens at microwave frequencies. In the final design a lens is demonstrated in a two-dimensional field mapping waveguide …
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Categorization of electromagnetic radiation scatterers by means of synthetic aperture radar (SAR) images
… Several researchers such as J. Huynen, E. Luneburg, S. R. Cloude, W.L. Cameron, R. Touzi and more have advanced the theoretical framework of polarimetric decompositions, theories that constitute the extraction of meaningful physical properties from a target. Polarimetric approaches are …