Applicability of an annealing coefficient for precision glass molding of As40Se60

Precision glass molding has a well-documented decrease in the index of refraction of the glass during the molding process. This index drop must be taken into account in the optical design in order to accurately determine the optical performance of the final lens. Knowing the annealing coefficient of the glass being molded allows the index to be fine-tuned by adjusting the cooling rate during the molding process. While annealing coefficients are available for visible glasses, the validity of using this method for chalcogenide gasses has not yet been investigated. This paper will determine the annealing coefficient for As40Se60 experimentally, and then verify the results by comparing calculated and experimental refractive index values for other cooling rates.