Figure 1

Depiction of the system. (a) A schematic diagram of the wave manipulation of light through a subwavelength hole drilled at an optically opaque silver thin film. The subwavelength hole is surrounded by a series of shallow and narrow grooves (typically λ/10 deep and λ/10 wide). Incident light, e.g., a circular polarized plane wave, is shined from the back side of the silver film, and a complex pattern, such as a letter L, appears in a given position. (b) The experimental set-up. A focusing objective is used to get a high-intensity incident wave on the back side, and an imaging objective can move forward and backward on the front side to see the field distributions at different heights.