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arXiv · cond-mat/0501715

Flat lens without optical axis: Theory of imaging

W. T. Lu·S. Sridhar
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Abstract

We derive a general theory for imaging by a flat lens without optical axis. We show that the condition for imaging requires a material having elliptic dispersion relations with negative group refraction, equivalent to an effective anisotropic refractive index n(theta). Imaging can be achieved with both negative (n<0) and positive (n>0) refractive indices. The Veselago-Pendry lens is a special case with isotropic negative refractive index of n(theta)=-1. Realizations of the imaging conditions using anisotropic media and inhomogeneous media, particularly photonic crystals, are discussed. Numerical examples of imaging and requirements for sub-wavelength imaging are also presented.

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W. T. Lu, S. Sridhar. 2005-12-15. Flat lens without optical axis: Theory of imaging. https://doi.org/10.1364/opex.13.010673

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