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Fused Silica Glass (SiO2)
Fused Silica is a hard, high temperature pure glass. Fused Silica is used for UV and visible components. Infra-red grades of Fused Silica are available for NIR use
Products
Windows
Lenses
Prisms & ATR
| Transmission Range | 0.18 to 2.2 μm (3 μm for IR grades) |
| Refractive Index | 1.47012 at 4 μm (1) |
| Reflection Loss | 7% at 0.4 μm (2 surfaces) |
| Absorption Coefficient | 10 x 10-6 cm-1 at 1 μm |
| Reststrahlen Peak | n/a |
| dn/dT | +12.9 x 10-6/°C (2) |
| dn/dμ = 0 | 1.3 μm |
| Density | 2.203 g/cc |
| Melting Point | 1600°C (Softening) |
| Thermal Conductivity | 1.38 W m-1 K-1 |
| Thermal Expansion | 0.55 x 10-6 /°C @ 300 K |
| Hardness | Knoop 500 with 200g indenter |
| Specific Heat Capacity | 703 J Kg-1 K-1 |
| Dielectric Constant | 3.78 at 25 GHz |
| Youngs Modulus (E) | 73.1 GPa |
| Shear Modulus (G) | 31.2 GPa |
| Bulk Modulus (K) | 36.7 GPa |
| Elastic Coefficients | n/a |
| Apparent Elastic Limit | 55 MPa (7980psi) |
| Poisson Ratio | 0.17 |
| Solubility | Insoluble in Water |
| Molecular Weight | 28.09 |
| Class/Structure | Amorphous Glass |
| μm | No |
|---|---|
| 0.20 | 1.55051 |
| 0.25 | 1.50745 |
| 0.30 | 1.48779 |
| 0.36 | 1.47295 |
| 0.40 | 1.46557 |
| 0.45 | 1.46055 |
| 0.50 | 1.46233 |
| 0.55 | 1.46008 |
| 0.60 | 1.45764 |
| 0.65 | 1.45623 |
| 0.70 | 1.45529 |
| 0.75 | 1.45424 |
| 0.80 | 1.45332 |
| 0.85 | 1.45125 |
| 0.90 | 1.45175 |
| 1.00 | 1.45024 |
| 1.10 | 1.44805 |
| 1.20 | 1.44602 |
| 1.30 | 1.44442 |
| 1.40 | 1.44342 |
| 1.50 | 1.44247 |
| 1.60 | 1.44147 |
| 1.70 | 1.44087 |
| 1.90 | 1.43951 |
| 2.00 | 1.43809 |
| 2.20 | 1.43501 |
| 2.40 | 1.43163 |
| 2.60 | 1.42789 |
| 2.80 | 1.42377 |
| 3.00 | 1.41925 |
| 3.20 | 1.41427 |
| 3.37 | 1.41099 |
Fused Silica is the glassy form of Quartz and is thus isotropic. Fused Silica is tough and hard and has a very low expansion. Normal varieties of Fused Silica contain water which gives strong absortion in the IR. Water-free varieties of Fused Silica are available.
REFERENCES:
(1) Handbook Optical Constants, ed Palik, V1, ISBN 0-12-544420-6
(2) Toyoda & Yabe J. Phys. D: Appl. Phys.,1 6 (1983)