lenses are often used to converge electromagnetic wave namely they convert incident phase front of feed antenna to a flat phase front. together, the lens and the feed create an electrically large aperture antenna. flat lenses provide the cost and weight benefits of the reflect-arrays, while maintaining the advantages of a lens antenna. these lenses use an array of unit-cells which are excited b...

We show that a classical imaging criterion based on angular dependence of small-angle phase can be applied to any system composed of planar, uniform media to determine if it is a flat lens capable of forming a real paraxial image and to estimate the image location. The real paraxial image location obtained by this method shows agreement with past demonstrations of far-field flat-lens imaging an...

We consider the scattering and lens rigidity of compact surfaces with boundary that have a trapped geodesic. In particular we show that the flat cylinder and the flat Möbius strip are determined by their lens data. We also see by example that the flat Möbius strip is not determined by it’s scattering data. We then consider the case of negatively curved cylinders with convex boundary and show th...

We demonstrate a variable focal length achromatic lens that consists of a flat liquid crystal diffractive lens and a pressure-controlled fluidic refractive lens. The diffractive lens is composed of a flat binary Fresnel zone structure and a thin liquid crystal layer, producing high efficiency and millisecond switching times while applying a low ac voltage input. The focusing power of the diffra...

Marfan syndrome (MFS) is a genetic disorder which is inherited by autosomal dominant traits. In MFS, lens displacement and cardiovascular involvement are important causes of morbidity and mortality in the clinical course of the disease. In this case study, the ocular involvement in a family with severe penetration of MFS is reported. Twelve members of a family (father, two daughters, three sons...

We present a review of several types of microwave antennas made of metamaterials, including the resonant electrically small antennas, metamaterial-substrate patch antennas, metamaterial flat-lens antennas, and Luneburg lens antennas. In particular, we propose a new type of conformal antennas using anisotropic zero-index metamaterials, which have high gains and low sidelobes. Numerical simulatio...

In this paper, we propose a wide-viewing-angle three-dimensional integral imaging using a curved screen and a curved lens array. Elemental images are projected to the curved screen. Incorporation of the curved screen and the curved lens array instead of a conventional flat display panel and a flat lens array expands the viewing angle remarkably. In addition adopting barriers between a curved le...