Sol-gel prepared glass for refractive and diffractive micro-optical elements and arrays

The fast sol-gel method enables facile preparation of siloxane-based glassy matrices, in which polymerization is completed within minutes and volume c hanges <5% take place upon curing. Single-face and two-face replication of micro-optical arrays have been obtained, as well as crack-free elements >10 mm thick. Minimizing shrinkage and enabling relaxation of the drying sol-g el are key factors in the elimination of cracking. These features and the r esulting optical quality of the glass make this method technologically and economically attractive for replication-produced micro-lenses and micro-opt ical arrays.