Fused Silica – SiO2
lenses, windows, mirrors, filters and prisms
Fused silica is produced by fusing high-purity silica sand, which consists of quartz crystals, at temperatures of around 1650 °C (3000 °F). This process produces a transparent glass with ultra-high purity and improved optical transmission in the deep ultraviolet. Fused silica has high working temperatures. It is used widely in the optics industry to for manufacturing precision optic components. It is used in semiconductor fabrication and laboratory equipment. Because of its superior ultraviolet transmission it is used to make lenses and optics for the ultraviolet spectrum.
Global Optics manufacture fused silica windows, lenses, prisms and beamsplitters
Transmission Range | 0.2 – 4.5 µ |
Crystal Structure | – |
Cleavage Plane | None |
Colour | Colourless |
Density | 32.202 |
Melting Point (°) | 1710 (Softening Point) |
Reflection Loss | 6.3% (2µ) for 2 surfaces |
Solubility index | Insoluble |
Hardness (Knoop) | 461.0 |
Thermal Conductivity (cal/cm sec°C) | 2.82×10-3 (41°C) |
Thermal Expansion coefficient (/°C) | 0.5×10-6 (20-900°C) |

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