Electromagnetic imaging using evanescent waves

Metallic strip gratings have a range of applications, from printed circuits boards to filters in microwave domains. These applications impose a rigorous and rapid quality control. This paper proposes the obtaining of electromagnetic images of metallic strip gratings using evanescent waves that are formed in slits. For their detection, two procedures can be use, namely, the diffraction of evanescent waves on circular apertures and respectively, the propagation through metamaterials, conical Swiss rolls type. In this case, the spatial resolution is better than λ/1000. The use of metamaterial, conical Swiss rolls type, allows the obtaining of a resolution in the range of λ/2000, the electromagnetic image being improved.