Effect of Polyvinyl Alcohol (PVA) Film Thickness on Some Optical Parameters

Abstract

Transparent films of Polyvinyl Alcohol with different thicknesses were made by applying solution casting technique at a temperature of (70°C). The optical absorption and transmission spectra were accomplished for all samples at room temperature over the wavelength region (190-1100) nm. Studying the effect of film thickness, which is measured with micrometer with an error not exceeding (5%), on optical parameters gives an indication that all these parameters are affected with thickness. The experimental results for Polyvinyl Alcohol films show that the optical energy gap decreases by the increasing of film thickness. The absorption coefficient, refractive index, extinction coefficient and real and imaginary parts of dielectric constant are increased by increasing the film thickness.