1. Sapphire has a high optical transmittance, so it is widely used as microelectronic tube dielectric material, ultrasonic conduction element, waveguide laser cavity, and other optical elements, as window materials for infrared military devices, space vehicles, high-intensity lasers and optical communications.

2. Sapphire has high rigidity, high strength, high working temperature, abrasion resistance, corrosion resistance characteristics, so sapphire substrate is often used in harsh environments, such as boiler water gauge (high-temperature resistance), commodity bar code scanner, bearing, and other precision manufacturing (wear resistance), coal, gas, well detection sensors and detector windows (anti-corrosion).

3. Sapphire has the characteristics of electrical insulation, transparency, good thermal conductivity, and high rigidity, so it can be used as the substrate material of integrated circuits, such as LED and microelectronic circuits, ultra-high-speed integrated circuit.