Next generation chalcogenide glasses for visible and IR imaging

A commercial supply of chalcogenide glasses has existed for several decades however little has changed in terms of new compositions, manufacturing methods or improvements of key metrics during this time. Since the early 1990s the University of Southampton has been developing a relatively unknown family of chalcogenides based on gallium and lanthanum. Glass melting methods have been significantly improved and characterization reveals significantly high thermal stability, to temperatures over 500°C, and improved mechanical strength and hardness. Previously restricted to transmission below 9 microns, new formulations of these glasses has extended transmission to beyond 13 microns whilst maintaining thermal and mechanical stability and some visible transmission. Moreover, these glasses are readily moulded and extruded, enable more economical component manufacture. As an optical fibre, these glasses have their loss minimum centred on the 3 - 5 micron band. Qualification of these materials in the laboratory is now underway with a view to working with end users to exploit their performance advantages