Thin films of Al-doped and undoped Lead Iodide crystals successfully grown by thermal evaporation technique. The lattice parameters determined by XRD. Optical and dielectric constants of Lead Iodide thin films have been determined from transmittance and reflectance measurements, for photon energies upto 6.185 eV. The absorption coefficient and bandgap energy were determined at room temperature by the normal incidence method. The bandgap energy of Lead Iodide at room temperature was found to be 2.498 eV. A careful analysis of absorption coefficients indicated the crystalline character of the sample studied; similar diagnosis was obtained from X-ray evidence, SEM analysis
