Fused Silica Window has some beneficial characteristics include:Broad transmission spectrumThermal stabilityScratch resistantLow thermal expansion coefficientGood homogeneity with excellent optical propertiesWider thermal operating rangeWhen the broadest transmission spectrum is required with high durability, a reasonable cost, these windows are ideal. Fused Silica is physically robust and resists chipping and scratches,coefficient of thermal expansion is quite low, so these windows maybe subjected to higher levels of thermal shock than glass or sapphire can withstand.Material: Ultraviolet Quality synthetic fused, Ultraviolet Quality nature fusedRefractive index:Dimension:+0,-0.2mmThichness :+/-0.2mmSurface flatness :less than 0.2um.Parallelism: less than 5arc minProtective Bevel :0.2mm-0.5 x45degreeSurface quality :120/80 to 20/10 scratch/digClear aperture: >90%Both sides polishedFire polished is recommended after mechanical polished.Qsheng custom fusedsilica window range includes all plano flat fused quartz components for far UV ultraviolet(JGS1)UV ultraviolet visible(JGS2) and infrared(JG3) transmission processed from a large inventory of stock materials rolled / welded drawn/cored, sheet, sawn sheet.Round, square and rectangular size available, in addition, we also provide a variety of single layer or multiplayer anti-reflecting coating on optical window.