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arXiv · 1502.05467

Flat Lens Criterion by Small-Angle Phase

Peter Ott·Mohammed H. Al Shakhs·Henri J. Lezec·Kenneth J. Chau
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Abstract

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 and can even predict the location of super-resolved images in the near-field. The generality of this criterion leads to several new predictions: flat lenses for transverse-electric polarization using dielectric layers, a broadband flat lens working across the ultraviolet-visible spectrum, and a flat lens configuration with an image plane located up to several wavelengths from the exit surface. These predictions are supported by full-wave simulations. Our work shows that small-angle phase can be used as a generic metric to categorize and design flat lenses.

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Peter Ott, Mohammed H. Al Shakhs, Henri J. Lezec, Kenneth J. Chau. 2015-02-19. Flat Lens Criterion by Small-Angle Phase. https://arxiv.org/abs/1502.05467

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