First of all, to be clear, sapphire could not have been called glass. Glass is a silica-based transparent post-fusion solidified body to which various elements have been added in order to meet different requirements, but the main component is silica. Sapphire is a crystal, a single-crystal arrangement of aluminum trioxide. Because sapphire becomes transparent after polishing, it is also called sapphire glass.
Sapphire glass, unlike what we initially understood, is not a natural sapphire, it emerged from the laboratory with the same chemical composition and physical properties as natural sapphire. Therefore, its price has dropped a lot, no longer as expensive as the original precious collector's item, but also gradually applied to many of our fields. Because it has good thermal properties, good electrical properties and dielectric properties, and anti-chemical corrosion, it is resistant to high temperature, good thermal conductivity, high hardness, infrared transmittance, good chemical stability. Therefore, it is often used to replace other optical materials to make optical components, infrared-transparent optical window, and is widely used in infrared and far-infrared military equipment, such as: used in night vision infrared and far-infrared scopes, night-vision cameras and other instruments and satellites, space technology instruments and meters, and used as a window of the high-power lasers, a variety of optical prisms, optical windows, UV and IR windows and lenses, low-temperature Observation ports of experiments, in navigation and aerospace instrumentation, etc. have been fully applied. This material is also used in the screens of cell phones and watch mirrors of wristwatches.
sapphire glass