Sapphire glass is an application of synthetic sapphire generally produced by subjecting aluminum oxide powder under extreme heat and pressure. Further heat treatment removes internal stresses before processing into thin sheets. The resulting output is a transparent material that is more durable than standard glass. Take note that a synthetic sapphire has the same physical properties as naturally-occurring sapphire.
Although sapphires are blue in color, a sapphire glass is highly transparent to wavelengths of light between 150 nanometers and 5500 nanometers. This range gives the material a very wide optical transmission band from ultraviolet to near-infrared.
It is worth mentioning that the human eye can only discern wavelengths between 380 nanometers and 750 nanometers. In other words, a sapphire glass passes the most basic requirement of an ideal screen: light should pass through it, and an individual should clearly see through it.
But the real advantage of sapphire glass lies in its extraordinary hardness. The material is nearly twice as hard as standard glass, and it is almost as hard as a diamond. For a quick reference, the sapphire has a value of 9, while a diamond has a value of 10 under the Mohs scale of mineral hardness. This means that sapphire glass is almost resistant to scratch unless it will come in direct and hard abrasive contact with a diamond.
|Diameter||0.5 to 350mm|
|Diameter Tolerance||±0.05 mm (Standard), up to +0.000/-0.002 mm|
|Thickness tolerance||±0.05 mm (Standard), up to +/-0.0.1mm|
|Surface Quality||60-40 S/D (Standard), up to 10-5S/D|
|Surface Figure||λ/4 or λ/10|
|Centration||1 Minute or 30 Second|
|Coating||uncoated, AR and HR|