ABSTRACT
Since the focusing is often carried out near the interface of two media in order to overcome the diffraction limit where it is necessary to take into account the vector nature of the electromagnetic field, the numerical investigations are carried using facilities unit based on the exact solution of Maxwell's equations. If an optical element whose axis of symmetry coincides with the optical axis is impacted by normally incident monochromatic electromagnetic wave with radial polarization, the electric vector of the incident wave retains only one radial component. The electromagnetic field in the image of a point source, located at infinity, is expressed by an aplanatic optical system in integral form as the expansion in plane waves. To focus light using evanescent waves it is required to form a focal spot near the media interface. The simplest refractive optical element that can focus light near the surface is a conical axicon.
