RESONANT SCANNING NEAR-FIELD OPTICAL MICROSCOPE

A scanning near-field optical microscope detects the evanescent field formed about an illuminated sample 14 via an interaction between the field and a local probe 20.The probe 20 is scanned across the sample surface in order to collect a complete image as a succession of scan lines. In the microscope of this invention, image collection is more rapidly performed by translating the probe 20 whilst it is oscillated at or near its resonance frequency. In this way a series of scan lines covering an area of the sample surface are rapidly collected, the length of each scan line being determined by oscillation amplitude.