Polarized infrared emission using frequency selective surfaces

Abstract

An emission frequency selective surface, or eFSS, is made up of a periodic arrangement of resonant antenna structures above a ground plane. By exploiting the coupling and symmetry properties of an eFSS, it is possible to introduce polarization sensitive thermal emission and, subsequently, coherent emission. Two surfaces are considered: a linearly polarized emission surface and a circularly polarized emission surface. The linearly polarized surface consisted of an array of dipole elements and measurements demonstrate these surfaces can be fabricated into high polarization contrast patterns. The circularly polarized surface required the use of an asymmetrical tripole element to maintain coherence between orthogonal current modes and introduce the necessary phase delay to realize circularly polarized radiation.

Optical properties of metallic films

“…essentially this means that we are altering the effective permittivity of the surface. Some good examples of practical metamaterial work in the IR include the control of spectral transmission [65], reflection [66], absorption [67], emission [68,69] reflected phase [70], emitted phase [71], as broad-band wave plates [72] and for molecular detection [73].…”

Directional thermal emission from a leaky-wave frequency-selective surface

“…5 This makes FSS a type of metamaterial (a metasurface) with electromagnetic properties typically not found in nature. FSS has been used to control the spectral, 6-8 phase, [9][10][11] and polarization 12 responses of incident radiation. This is often achieved via scaling established radio frequency designs to infrared wavelengths 13 which has significance at infrared wavelengths because it controls the emissivity of the surface, and hence heat transfer via radiation.…”

Directional thermal emission from a leaky-wave frequency selective surface

“…This is often achieved via scaling established radio frequency designs to infrared wavelengths 13 which has significance at infrared wavelengths because it controls the emissivity of the surface, and hence heat transfer via radiation. For example, both Ginn et al 12 and Liu et al 14 engineered the spectral emissivity of a surface, using dipole and cross elements, respectively. In these cases the angular distribution of the emitted radiation is still relatively diffuse.…”