EXPERIMENTAL IMAGE-PROCESSING OF SMALL SUPPORTED METALLIC PARTICLES (1-3 NM)

Metallic particles crystallized on MgO cubes have been observed in profile view in HRTEM. The images are processed in order to improve the visibility of the particles morphology and the eventual defects at the interface metal/MgO. Three different filters have been used, all of them working in the Fourier space. A band pass filter keeping all the spatial frequencies close to the (200) reflections improves the contrast of the particles against the noise. Bragg filters around the (200) reflections show up the lattice defects. A new filtering by subtraction of the background, improves both the contrast of the particles and the details at the interface.