Evaluation of Demolding Force by Parallel Mold Press for Glass Imprint

Measurement method of compressive or tensile forces during glass imptrint was developed by improving a lens mold press machine. Deformation and demolding behaviors could be quantified under the pressing using a glassy carbon and a tungsten carbide mold. After the pressing of a glass at slightly above the deformation temperature followed by the cooling of the glass and mold under applying a small tensile force, an abrupt demolding was observed below the glass transition temperature, which was affected by the pressing temperature and the glass compositions. This measurement method should be useful for the characterization of deformation and demolding behaviors of wide variety of glasses not only for optical lens but also for nanostructured optical components.