SCANNING PROBE OPTICAL MICROSCOPY USING A METALLIC PROBE TIP

We propose a scanning probe optical microscope which features a metallic probe tip for detecting evanescent photons localized near the surface of fine structures of the sample. A metallic probe is used for converting the evanescent photons localized near the sample surface to the propagating photons by scattering, but not for transmitting the converted photons through it as a waveguide. The light scattering is detected in far field with external condenser optics. During the measurement, the probe tip vibrates vertically very near the surface, so that the light intensity related to the conversion from evanescent photons to propagating photons is lock-in detected. Experimental results show the exponential decay due to the evanescent field as a function of distance. The experimental results of surface profiling for a smoothly curved surface and a heavily scattering surface are also presented.