APERTURELESS NEAR-FIELD SCANNING RAMAN MICROSCOPY USING REFLECTION SCATTERING GEOMETRY

Abstract

A laser beam (24) is focused to a small spot size onto a sample (14). A metal probe or metal coated probe (16) has its tip positioned within the beam, close to or contacting the sample (14). A reflected Raman signal (28) is detected. The probe (16) enhances the Raman signal, and provides high resolution. The probe may be silver coated; the distance between its tip and the sample can be controlled by either the principle of the cantilever or tuning fork; and it may be scanned across the surface of the sample (14), with its position monitored via optical means (20, 22).