APPARATUS AND METHOD FOR ENHANCED OPTICAL TRANSMISSION THROUGH A SMALL APERTURE, USING RADIALLY POLARIZED RADIATION

摘要

An apparatus for enhanced transmission of radiation, comprising at least one radiation source (12), a metal plate (18) with a first (20) and a second (22) surface and at least one aperture (24) provided in the metal plate (18) and extending from the first (20) to the second (22) surface, the metal plate (18) having a periodic surface topography (26) provided on at least one of the first (20) and the second (22) surfaces, and radiation (13) coming from the radiation source (12) and being incident on one of the surfaces (20,22) of the metal plate (18) interacts with a surface plasmon mode on at least one of the surfaces of the metal plate (18), thereby enhancing transmission of radiation through the at least one aperture (24) of the metal plate (18). The apparatus for enhanced optical transmission comprises means (15) for generating radially polarized radiation (16), which is incident on one of the surfaces (20,22) of the metal plate (18) with a surface topography (26), resulting in a more efficient coupling of the radiation to the plasmons and thereby in a further enhancement of the optical transmission.