scanning near-field optical microscopy microwave scanning near-field microscopy Microscopy where a probe consisting of a microwave radiation source transmitted through a tapered optical fibre is positioned very close to (<10 nm from) the surface of the specimen. The tip is coated with metal (to prevent light from escaping from the sides) and near-field (or evanescent field) microwave radiation is emitted through a small opening or 'aperture' (50-100 nm in diameter) at the apex of the probe. An image is produced by scanning the probe over the specimen and detecting the disturbance of the microwave near-field as a function of position. A force feedback loop is used to maintain a fixed relationship between the probe and surface during scanning. NSMM microwave near-field scanning microscopy near-field scanning microwave microscopy CHMO:0000123 SNMM