Ultraviolet-Grade Fused Silica Windows transmit light reaching as far down as 160nm, with maximum transmission from 195-2100nm. The broad transmission range from UV-VIS-NIR makes it ideal for UV applications, as well as through the visible spectrum to NIR region. UV fused silica also provides a low coefficient of thermal expansion with excellent homogeneity. Due to its durability qualities, fused silica is also often used in applications where high laser damage threshold or high heat is required