Diffraction gratings were recorded both optically and interferometrically in dichromated poly(vinyl alcohol) (DCPVA) films by means of dichromate photoreduction. Aniline was used as a chemical developer, through in situ polymerization in the unreduced parts of the film. The resulting composite material shows the optical and chemical properties of polyaniline and the mechanical resistance of PVA. Characterization of the gratings gave a line width of 12.2 mum and a diffraction efficiency of 32%. Uv-vis spectroscopy was used to study dichromate photoreduction and the optical properties of the composite..