Abstract A CO₂ laser was employed as the heat source to deposit films of SiO₂. The report discusses the measurement of the refractive indices of the thin transparent films produced. Investigation into the various techniques available for measuring the index of refraction led to the selection of Abeles method for determination of the Brewster angle. A helium-neon laser was used as the source of incident polarized light, while a selenium photocell monitored the reflected...