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We report results on the processing and characterization of tellurite-based glass in the TeO2–Bi2O3–ZnO (TBZ) glass family and efforts to reduce their absorption loss due to residual hydroxyl (OH) content. We show that the introduction of alkaline or alkaline earth in the glass network, drying of the batch with fluorine-based raw materials before melting, and melting of the glass in O2-rich atmosphere can lead to a significant reduction in OH content. Employing these steps in TBZ glass processing resulted in a 93% reduction of OH content as compared with a reference composition. The reduction in OH content was verified by a decrease of the absorption band center at 3000 cm−1 as well as a decrease of the free volume in the glass. The addition of F in the glass network was found to reduce the fraction of nonbridging oxygen associated with OH. X-ray fluorescence spectrometry was used to determine the amount of remaining F.

In this paper, we report the development of a kinetic model for precisely predicting glass material property response to a defined molding profile. The glass viscosity, thermal expansion, and specific heat properties for two commercial optical glasses, P-SK57 and L-BAL35 were measured and are reported in this paper. These data were used with the Tool-Narayanaswamy-Moynihan (TNM) model for glass structural relaxation in order to develop a thermal expansion model that simulates the glass workpiece changes through the critical cooling profile where the final workpiece shape is determined. The results show a structural relaxation model incorporated into an ABAQUS FEM code that precisely models the thermal expansion behavior acknowledging that the theory of structural relaxation is a critical element in predicting the final size and shape of a molded lens.