Infrared chalcogenide glass aspherical microlens array fabricated using glass-to-glass molding

Precision glass molding (PGM) represents a highly effective method for producing infrared chalcogenide (ChG) glass aspherical microlens arrays (AMLA). However, ChG glass, primarily composed of Ge, As, and Te, exhibits lower chemical stability compared to typical silicate glass. When subjected to high temperatures and pressures during molding with a nickel-phosphorus (Ni-P) mold, ChG glass tends to react with the Ni element, resulting in the formation of a shielding layer on the lens surface. This phenomenon significantly impacts the infrared transmittance of the ChG glass lens, rendering Ni-P mold unsuitable for direct apply in ChG glass PGM. Ni-P mold can be effectively utilized for the high-temperature molding of silicate glass, serving as the intermediate mold for subsequent low-temperature molding of ChG glass. This dual-step approach has been validated by detailed analysis of the profiles of the final ChG glass AMLA, thereby providing a viable method for the fabrication of ChG glass AMLA through PGM.