Near-field imaging with far-field data

Near-field imaging with far-field data

Using the inverse diffractive grating problem as an example, we demonstrate how a super-resolution can be achieved stably by using far-field data. The idea is to place a slab of a homogeneous medium with a large index of refraction above the grating surface, and more propagating wave modes can be utilized from the far-field data which contributes to the reconstruction resolution. © 2016 Elsevie...

Far-field subwavelength imaging with near-field resonant metalens scanning at microwave frequencies

A method for far-field subwavelength imaging at microwave frequencies using near-field resonant metalens scanning is proposed. The resonant metalens is composed of switchable split-ring resonators (SRRs). The on-SRR has a strong magnetic coupling ability and can convert evanescent waves into propagating waves using the localized resonant modes. In contrast, the off-SRR cannot achieve an effecti...

Individual gold dimers investigated by far- and near-field imaging.

Plasmon resonances in 3D nanoparticle arrangements can produce strong localized optical fields, which are of importance for any application involving interaction of light with subwavelength volumes of matter down to the molecular level. In particular, remarkable field enhancement and confinement occur in a dimer geometry formed by two identical closely spaced particles. Although, recent advance...

Investigate probability of damage of Earth dam under Near-field and Far –field earthquake : Case study Gotvand earth dam

The main goal of preset research is investigate the effects of vertical component of Near-Fault and Far-Field earthquake records on the probability of overtopping induced damage of earth dam due to the reduction of freeboard due to the settlement of dam crest. In this respect 12 different earthquake record are selected. Nonlinear dynamic analysis of earth dam is implemented with FLAC 3D using F...

An Alternative Spherical near Field to Far Field Transformation