Detailed characterization for double blended nanocomposite films of PVP (Polyvinylpyrrolidone)/CMC (carboxy-methyl cellulose) polymer blends doped with SnO2 and ZnS nanoparticles based on different proportional concentrations (1-x)SnO2 -x ZnS (x = 0, 0.25, 0.5, 0.75, 1) has been represented. Nanoparticles were synthesized based on the sol-gel technique, while nanocomposite films were prepared using the casting technique. The crystalline structures for both nanoparticles and nanocomposite films before and after laser exposure have been discussed by the x-ray technique. Fourier transform infrared spectroscopic technique (FTIR) revealed variations in the vibrational bands intensities and locations under the effect of both laser exposure and nanoparticles. The morphological features of the studied samples have been discussed through SEM (Scanning Electron Microscope) images. The optical properties (linear-nonlinear) of nanocomposite films have been discussed in details using UV–Vis spectroscopy technique. The refractive index has been calculated based on different proposed models. Similarities in the refractive index values have been observed. The effect of direct laser beam exposure on the estimated values of energy gap Eg has been represented in details. Eg values showed a reduction from 5.1 eV (for undoped films) to 4.8 eV (for laser exposed doped films). Nanocomposite films fully doped with 100% zinc sulphide nanoparticles exhibited the lowest Eg value (4 eV). Linear and nonlinear optical parameters confirmed the dominant effect of direct laser exposure compared with the particle size effect.