Thin films of zirconium dioxides were deposited on room temperature glass substrates using emission from the dc magnetron sputtering plasma glow discharge as a process control for the reactive process inside the deposition chamber in low pumping speed vacuum system. An unbalanced magnetron source was used in an enclosed volume, within a vacuum chamber, into which oxygen gas was admitted. A systematic control of the reactive gas partial pressure allows injection of reactive gas into the deposition chamber, provided with a fast response time by observation of the spectral line emission of the sputtered zirconium target. This feedback loop control allowed the production of localized-optimized films of Zirconium dioxides. The optical quality and optimization process were assessed by ellipsometry and spectrophotometry.