Analytical technique for subwavelength far field imaging

Abstract

We develop an analytical technique for retrieving the size and shape of subwavelength objects using far-field measurements. The approach relies on subwavelength diffraction gratings scattering evanescent information into the far field along with a numerical algorithm that is capable of deconvoluting this information based on the far-field intensity measurements. Several examples are presented, demonstrating resolution on the order of λ0/20. The developed method can be used at any frequency range, and may become a practical alternative to scanning near-field microscopy.