Cu-doped and undoped Lead Iodide crystals have been grown by gel technique. Then, thin films of Cu-doped and udoped Lead Iodide crystals have been deposited, of various thicknesses, successively by thermal evaporation technique. These thin films were characterized by XRD, Transmittance and Reflectance. The lattice parameters of thin films of Cu-doped and undoped, were well matching with the ASTM data for Lead Iodide. The absorption coefficient, band gap energy and dielectric constants were determined at room temperature by normal incidence method. The transmittance measurements enable the evaluation of the value of band gap energy Eg.
