This work presents a detailed spectrophotometric analysis of tantalum pentoxide (Ta2O5) thin films deposited for use in military optical components, with measurements conducted in the visible spectral range of 400–800 nm. The primary objective is to evaluate how the thickness of thin films and its surface and interface boundary roughness influence the optical response, particularly reflectance characteristics, which are critical for applications such as anti-reflective coatings, optical filters, and stealth-related technologies for military use.