Precision glass molding: cost efficient production of glass-optics with spectral range from 180nm ultraviolet to 13μm thermal infrared

Precision Glass Molding (PGM) is a manufacturing method which enables cost efficient production of highly complex glass optics in medium to high quantities. The produced glass optics can be intended for applications in a spectral range from 180 nm ultraviolet to 13 μm thermal infrared. However, it is necessary to choose the glass type according to their intended task and wavelength domain. Typical glass types used for PGM are low Tg optical glasses. Fused silica and chalcogenide glasses expand applications to UV and IR. The use of different glass types entails a variation of the necessary temperature range in which the glass can be processed. The processing temperature of these glasses varies between 200 and 1400 °C. To ensure an economical processing, mold materials and mold manufacturing technologies are varied according to the task at hand. The application of PVD thin film coatings is one of the methods commonly used for prolonging the molds service lifetime. However, the specific coating has to be selected suitable for the glass type and mold material. To illustrate the differences in molding optical grade low Tg glass, fused silica and chalcogenide glass a representative process chain for PGM is described and peculiarities for each glass category is presented in regards to the state of the art. Finally an outlook on ongoing and future issues for applied research in the filed of PGM is given.