Sapphire quartz drilling windows for optical applications
Quartz (Fused Silica)
UV Grade Fused Silica is synthetic amorphous silicon dioxide of extremely high purity providing maximum transmission from 195 to 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. Transmission and homogeneity exceed those of crystalline quartz without the problems of orientation and temperature instability inherent in the crystalline form. It will not fluoresce under UV light and is resistant to radiation. For high-energy applications, the extreme purity of fused silica eliminates microscopic defect sites that could lead to laser damage.
Sapphire
Sapphire (Al2O3) has exceptional surface hardness and can only be scratched by a few materials other than itself. This hardness allows it to be made into much thinner optics than other substrates. Sapphire is chemically inert and insoluble to water, common acids, and alkalis for temperatures up to 1,000 °C. Sapphire is transparent in the UV to the IR (150 nm - 4.5 µm). It is commonly used in IR laser systems and has an ordinary refractive index of 1.754 and an extraordinary refractive index of 1.747 at 1.064 µm.
