Abstract: The invention concerns a method for exciting a sub-wavelength inclusion structure, comprising: providing a first medium having a first refractive index ni and a second medium having a second refractive index nt, wherein ni>nt, wherein the sub-wavelength inclusion structure is arranged at a boundary between the first and second media, wherein the sub-wavelength inclusion structure exhibits polarizability properties; and directing light through the first medium towards the sub-wavelength inclusion structure. The angle of the incident light to the normal of the boundary, ?i, is such that, for a given set of: frequency of the light; surface density of inclusions; average polarizability of the inclusion structure at the frequency; first refractive index; and second refractive index, ?i fulfils at least one of the relations for s-polarized light and for p-polarized light described herein.

Abstract: A holder, e.g., for rolls of paper is configured such as to dispense a paper web from the holder via a web braking element (14, 15, 17), which may have alternative forms. The web braking (14, 15, 17) prevents paper from being dispensed uncontrollably from the holder as a result of inertia forces or some other circumstance. The holder is comprised preferably of two major parts, namely a back plate (1) and a causing (2), which houses the roll (4) and roll support means (8, 9). When the roll (4) is placed horizontally in the casing the roll is supported on two shafts (8). When the roll extends vertically in the casing, it is supported by a shelf (9). The shelf has formed therein an aperture (10) through which the paper web passes.