<title>Glass ceramics for optical applications in the visible and infrared regions with low coefficient of thermal expansion</title>

Abstract

A glass ceramic with high transmission values up to 4.5 micrometers and with extremely low thermal expansion is presented. In addition a large variety in shaping processes, for instance blocks of large dimensions, tubes, domes, and capillaries, are addressed. Furthermore a sintered cordierite glass ceramic is presented combining a low value in relative length change, a high temperature stability and a high transparency in the visible and median range infrared region. The properties include a high Young's modulus and a high Knoop hardness relative to normal IR-glasses. The application of the powder processing technique can be used successfully to prepare fully dense, complex-shaped articles.