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arXiv · 1012.5107

Newtonian photorealistic ray tracing of grating cloaks and correlation-function-based cloaking-quality assessment

Jad C. Halimeh·Roman Schmied·Martin Wegener
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Abstract

Grating cloaks are a variation of dielectric carpet (or ground- plane) cloaks. The latter were introduced by Li and Pendry. In contrast to the numerical work involved in the quasi-conformal carpet cloak, the refractive-index profile of a conformal grating cloak follows a closed and exact analytical form. We have previously mentioned that finite-size conformal grating cloaks may exhibit better cloaking than usual finite-size carpet cloaks. In this letter, we directly visualize their performance using photorealistic ray-tracing simulations. We employ a Newtonian approach that is advantageous compared to conventional ray tracing based on Snell's law. Furthermore, we quantify the achieved cloaking quality by computing the cross-correlations of rendered images. The cross-correlations for the grating cloak are much closer to 100% (i.e., ideal) than those for the Gaussian carpet cloak.

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Jad C. Halimeh, Roman Schmied, Martin Wegener. 2010-12-22. Newtonian photorealistic ray tracing of grating cloaks and correlation-function-based cloaking-quality assessment. https://doi.org/10.1364/oe.19.006078

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