Sol-gel techniques were used to prepare SiO 2 TiO 2 planar and strip optical waveguides. Thermal densification for planar waveguides and laser densification for strip waveguides were performed on films prepared from two different solutions on silica and soda-lime substrates. The resulting waveguides were optically characterized and the optical differences between furnace- and laser-densified films were shown. A better insight of the effect of the densification method, solution and substrate on the resulting film was gained by the study of their chemical composition by nuclear analyses.