Thermodynamic coupling analysis of precision molding process for chalcogenide glass microlens array under multiple loads.

Precision glass molding (PGM) technology, as an efficient and straightforward method for producing glass lenses, has been widely applied in the mass production of aspheric glass lenses. However, molding complex surfaces such as free-form and array surfaces is still in its infancy. To reveal the variations of temperature and stress of microlens array (MLA) optical elements during the molding process, a simulation model was established using the finite element method (FEM), and the heating and forming stages of a chalcogenide glass MLA optical element were studied. The influence of process parameters on the stress distribution of glass lenses was analyzed. Considering the long heating time and large deformation required for spherical chalcogenide glass preforms, the molding process was optimized. Different loads were applied at various stages of heating and pressurization of the preform, which reduced the stress in MLA optical elements during the molding process and decreased the molding time by over 21%.