Device and method for shielding at least one sub-wavelength-scale object from an incident electromagnetic wave

A device for shielding a sub-wavelength-scale object from an electromagnetic wave incident on said device, according to a direction of incidence, said device comprising:

• a layer of dielectric material, a surface of which has a change of level forming a step, said dielectric material having a first refractive index;
• and
• a medium having a second refractive index that is lower than the first refractive index of said dielectric material, wherein the medium is in contact with said step, and
• wherein said sub-wavelength-scale object is located within said device in a quiet zone extending above said surface, in a vicinity of said step, in a same direction as the direction of incidence of said incident electromagnetic wave.