Directional thermal radiation emitting structure, has internal layer made up of material having predetermined refractive index that satisfies predetermined equation in spectral band

摘要

The structure has an internal layer (42) immerged in a matrix constituted by two external layers (40, 41), where the internal and external layers are made of material having different refractive indexes. The refractive index of the internal layer has real and imaginary parts satisfying corresponding inequalities. The refractive index of the internal layer satisfies an equation in a spectral band.