Optical BK7 Glass Dome Cover    Dome windows are hemispheres. The two optical surfaces are an equal thickness apart, creating a naturally strong shape that gets tougher under pressure. This makes dome windows ideal for underwater environments and in applications such as camera dome ports and submersible windows.   BK7 or K9L domes  are used primarily in meteorology applications. BK7 offers excellent transmission from 300nm up to 2µm. BK7 is a relatively hard material, with excellent chemical durability.  UV fused silica domes: For applications operating in the deeper UV range, Worldhawk offers a range of UV fused silica domes. Fused silica domes are commonly used in underwater applications at extremely high pressures. Sapphire domes: For infrared applications we can provide sapphire domes. Sapphire is an extremely hard material with transmission of over 80% in the 2-5µm wavelength range. As with fused silica, sapphire is able to withstand extreme pressures, making it the perfect material for underwater camera and missile fairing applications. Specification: Material N-BK7 , H-K9L, UV Fused Silica, Sapphire, IR crystal Diameter 5mm-150mm, 150-300mm Diameter Tolerance +/-0.1mm Thickness >2mm Thickness Tolerance ±0.2~0.1mm Center Deviation 3-5' Surface Accuracy 1L 1/2L 1/4L or According to size Surface quality 80/50 60/40 Coating Both side Antireflection Coatings Chamfers 0.2 x 45° typical