Our UV Fused Silica Bi-Convex lenses are available uncoated or coated with a variety of multi-layer antireflection coatings. All lenses feature λ/8 surface accuracy and 20-10 scratch-dig surface quality. UV Fused Silica is synthetic amorphous silicon dioxide of extremely high purity providing maximum transmission from 195-2100 nm. This non-crystalline, colorless silica glass combines a very low thermal expansion coefficient with good optical qualities and excellent transmittance in the ultraviolet region. Also, it will not fluoresce under UV light and is resistant to radiation.