The present disclosure concerns a device for forming at least one focused beam in a near zone, from an electromagnetic wave incident on said device. Such device is remarkable in that it comprises at least one layer of a dielectric material comprising at least partially a first element, said first element having a first refractive index value, said first element comprising at least partially a second element, said second element having a second refractive index value greater than said first index value, and wherein said second element comprises at least a base surface, defined with respect to an arrival direction of said electromagnetic wave, and wherein said at least a base surface comprises at least two opposite edge line segments whose shape and associated base angles between said at least a base surface and a lateral surface of said second element, in a vertical plane with respect to said at least a base surface, control a shape of said at least one focused beam.