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arXiv · 0708.0049

Near-Field Focusing Plates and Their Design

A. Grbic·R. Merlin
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Abstract

This paper describes the design of near-field focusing plates, which are grating-like structures that can focus electromagnetic radiation to spots or lines of arbitrarily small subwavelength dimension. A general procedure is outlined for designing a near-field plate given a desired image, and its implementation at microwave frequencies is discussed. Full-wave (method of moments) simulations clearly demonstrate the near-field plate's ability to overcome the diffraction limit. Finally, it is shown that the performance of near-field plates is weakly affected by losses.

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A. Grbic, R. Merlin. 2007-08-01. Near-Field Focusing Plates and Their Design. https://doi.org/10.1109/tap.2008.929436

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