| Sapphire windows (2.5 λ)
Sapphire is an excellent material for windows, combining outstanding hardness, high thermal conductivity properties with an extremely wide transmission range from 170nm to 5.3 microns. It is often used for pressure windows, being approximately five times stronger than glass, and can be used at temperatures up to 2000°c. As sapphire has such hard structural strength, Sapphire Windows can be made much thinner than other materials, which can be useful. |