Scanning near‐field optical microscopy (SNOM)

SNOM is a non‐contact stylus microscopy analogous to STM. Optical near‐field interaction is used to sense approach and optical properties on the nanometre scale (≅1 nm normal, 20–50 nm lateral). SNOM was demonstrated in transmission and reflection, in a topographic mode, and with amplitude as well as phase objects. The excitation of plasmons in the SNOM ‘tip’, a very recent development, greatly enhances sensitivity and permits intriguing new optical experiments. Overcoming the limit of diffraction, SNOM turns a long‐held dream of optical microscopists into reality. 1988 Blackwell Science Ltd