UV grade fused silica (UV FS) and borosilicate crown glass are the optical materials used in the majority of EKSMA OPTICS optical components. UV grade FS and borosilicate crown glass conform the requirements for Shott Glass SUPRASIL and BK7 respectively. EKSMA OPTICS occasionally uses corresponding glasses made by different glass manufacturers, but only when it does not result in a significant change of optical properties.
Ultraviolet grade Fused Silica (UVFS)
UV grade fused silica offers both highest transmission (especially in deep-UV) and very low fluorescence levels (approximately 0.1% that of fused natural quartz). In deep-UV applications UV grade fused silica is an ideal choice. Its tight index tolerance assures highly predictable lens, window, prism, etc. specifications. Very low bubble content makes it really unique.
Borosilicate crown glass (BK7)
BK7 is an optical material used in a large fraction of EKSMA OPTICS products. It is relatively hard glass, does not scratch easily and can be handled without special precautions. The inclusion and bubble content of BK7 is very low: cross-section totally less than 0.03 mm2 per 100 cm3. Another important feature of BK7 is its excellent transmission down to 350 nm. Due to these properties, including inexpensiveness, BK7 is used widely throughout the optics industry.