Poly(ethylene terephthalate) (PET), Poly(ethylene naphthalate) (PEN) and oriented polyamide (oPA) films are studied in terms of their optical, electronic and vibrational properties using two Spectroscopic Ellipsometry (SE) techniques working in Vis-far UV (FUV); 1.5-6.5 eV, and IR; 900-3000 cm(-1), energy ranges. The corresponding spectra were fitted using the appropriate modeling and analyses procedures. It is presented the interpretation of the features deduced in the UV-FUV range to the electronic transitions occur at specific bonds of the respective polymer monomers, as well as the assignment of the IR peaks to the vibrational modes of the different chemical bonds. Based on the results deduced the calculation of the bulk epsilon(omega) for each polymeric material in the extended energy region from IR up to FUV is realized. (C) 2003 Elsevier B.V. All rights reserved.