Silver nanoparticles were synthesized in vacuum (10−7) by using a Nd:YAG high-power pulsed laser without any catalytic gas and/or thermal annealing processes. The ablated material was collected on several SiO2/Si substrates (with 50 nm thickness) deposited before the laser ablation with a plasmaenhanced chemical vapor deposition system. The substrates were analyzed with the aid of a variable angle spectra ellipsometer at different angles. The analysis revealed the presence of a surface plasmon resonance at about 3 eV, which is in good agreement with results in the literature.Adeconvolution method utilizing the Lorentz model was applied to fit the experimental optical absorption peaks in order to recognize different groups of nanoclusters with different sizes varying from 2 to 10 nm in radius. Electronic elaborations of scanning electron microscopy of the embedded particles in the SiO2 matrix were also carried out to measure their densities as a function of the deposition time and dimension distributions. The experimental measurements were performed at the INFN-LNS laboratory of Catania and at the MT laboratory of the FBK-IRST foundation of Trento.