Zinc Tellurite Glasses

Glass formation was observed in the system ZnO‐TeO 2 in mixtures containing 20 to 40 mole % ZnO. Softening occurred at 350°C and the glasses crystallized at 400°C. High dielectric constants (ca. 20) and high electrical resistivities (ca. 10 11 ohm‐cm −1 ) were measured. The zinc tellurite glasses have a higher density and refractive index and are considerably softer than silicate glasses. The optical transmission range was between 0.38 and 6.6μ with two absorption bands in the infrared. Spectra of Cu 2+ and Nd 3+ doped samples are also given.