Specifications:
| Materials | IR grade Barium fluoride crystals | Diameter Range | ~ 200mm |
| Aperture | >90% | Dimension Tolerance | +0.0/-0.1mm |
| Thickness Tolerance | +/-0.2mm | Surface Quality | 60/40 S/D |
| Parallelism | 1 arc minute | Chamfer | 0.3-0.5mmx45degree |
| Coating | Optional protective coating |
Physical and Optical Properties:
| Transmission Range | 0.15 to 12 μm | Refractive Index | 1.45 at 5 μm (1) |
| Reflection Loss | 6.5% at 5 μm (2 surfaces) | Absorption Coefficient | 3.2 x 10-4cm-1 @ 6 μm |
| Reststrahlen Peak | 47 μm | dn/dT | -15.2 x 10-6 °C (2) |
| dn/dμ = 0 | 1.95 μm | Density | 4.89 g/cc |
| Melting Point | 1386°C | Thermal Conductivity | 11.72 W m-1 K-1 @ 286 K |
| Thermal Expansion | 18.1 x 10-6 /°C @ 273 K | Hardness | Knoop 82 with 500g indenter (4) |
| Specific Heat Capacity | 410 J Kg-1 K-1 (3) | Dielectric Constant | 7.33 at 1 MHz |
| Youngs Modulus (E) | 53.07 GPa (3) | Shear Modulus (G) | 25.4 GPa (3) |
| Bulk Modulus (K) | 56.4 GPa | Elastic Coefficients | C11 = 89.2 C12 = 40.0 C44 = 25.4 (2) |
| Apparent Elastic Limit | 26.9 MPa (300psi) (4) | Poisson Ratio | 0.343 |
| Solubility | 0.17g/100g water at 23°C | Molecular Weight | 175.36 |
| Class/Structure | Cubic CaF2, Fm3m, (111) , cleavage |
Barium Fluoride is often suitable for applications in the passive IR band (8 to 14 μm) and is often used as a viewport window for thermal imaging inspection application in electric power facilities and petroleum industries. For an equivalent thickness the transmission extends approximately 1 micron further into the IR than Calcium Fluoride.
Hangzhou Shalom EO also provided the BaF2 windows with the protective coatings and assembly windows with metal holders.
Curves:
Transmission curve of the BaF2 windows of different thickness
 Windows02.jpg)
 Windows01-500x400.jpg)
 Windows01-50x40.jpg)