Sapphire Windows

The working wavelength of sapphire is from 200nm to 5000nm. There is no absorption in this working band. When the light beam propagates in the sapphire window, birefringence will occur. The surface reflectivity of the uncoated sapphire window is about 8% per surface, and the transmittance through an uncoated sapphire window is about 85%. Sapphire has a very high surface hardness and can only be scratched by a few substances. It has good heat resistance and weather resistance, and its chemical properties are stable. It is insoluble in water, common acids and alkalis even at a temperature of 1000℃. Natural sapphire has a bright blue color due to the presence of metal ions such as iron or titanium in the crystal. It sometimes fluoresces when exposed to ultraviolet light. Artificial sapphire is colorless and transparent.