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Flat lens criterion by small-angle phase



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


It is sometimes possible to image using a flat lens consisting of planar, uniform media. There is conceptual division between theoretical flat lens proposals, which require exotic properties such as negative index or counter-intuitive behavior such as evanescent wave amplification, and practical implementations, which are based on metallic thin films and restricted to transverse-magnetic polarization. With the goal of consolidating the flat lens literature by a universal method of analysis, we introduce a criterion based on angular dependence of small-angle phase that can be applied to any planar medium to determine if it is a flat lens and to estimate its image plane location. The analysis is substantiated by consistency with past at lens results spanning diverse configurations and operation conditions. We highlight new possibilities of a flat lens for transverse-electric polarization using dielectric layers and a broadband at lens working across the ultraviolet-visible spectrum.
Optics Express


Flat lens, Metamaterial, Optical Near-field, Paraxial Image, Electromagnetic Simulations, Transfer matrix Method, finite


Ott, P. , Al Shakhs, M. , Lezec, H. and Chau, K. (2014), Flat lens criterion by small-angle phase, Optics Express, [online],, (Accessed June 15, 2024)


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Created November 30, 2014, Updated October 12, 2021