Specifications:
| Materials | IR Grade Calcium Fluoride Crystals | Aperture | >90% |
| Dimension Tolerance | +0.0/-0.2mm | Thickness Tolerance | +/-0.1mm |
| 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 | 0.13 to 10 μm | Refractive Index | 1.39908 at 5 μm (1) (2) |
| Reflection Loss | 5.4% at 5 μm | Absorption Coefficient | 7.8 x 10-4 cm-1 @ 2.7 μm |
| Reststrahlen Peak | 35 μm | dn/dT | -10.6 x 10-6 /°C (3) |
| dn/dμ = 0 | 1.7 μm | Density | 3.18 g/cc |
| Melting Point | 1360°C | Thermal Conductivity | 9.71 W m-1 K-1 (4) |
| Thermal Expansion | 18.85 x 10-6 /°C (5)(6) | Hardness | Knoop 158.3 (100) with 500g indenter |
| Specific Heat Capacity | 854 J Kg-1 K-1 | Dielectric Constant | 6.76 at 1MHz (7) |
| Youngs Modulus (E) | 75.8 GPa (7) | Shear Modulus (G) | 33.77 GPa (7) |
| Bulk Modulus (K) | 82.71 GPa (7) | Elastic Coefficients | C11 = 164 C12 = 53 C44 = 33.7 (7) |
| Apparent Elastic Limit | 36.54 MPa | Poisson Ratio | 0.26 |
| Solubility | 0.0017g/100g water at 20°C | Molecular Weight | 78.08 |
| Class/Structure | Cubic (111) cleavage |
Calcium Fluoride (CaF2) Windows, featuring high average transmission spanning from deep UV to near IR spectra (180nm-8 µm), and low absorption coefficients, are excellent for applications in the UV, Visual, and IR regions, resulting in miniature signal loss and high optical efficiencies. CaF2 window has a low chromatic dispersion relative to other IR materials, meaning it spreads out or distorts light to a minimum extent as it passes through the window. Calcium Fluoride also has the advantages of high damage threshold and chemical resistance. Its Group Velocity Dispersion (GVD) is the lowest among the IR transmitters, therefore CaF2 is also recommendable for Femtosecond IR lasers.
Hangzhou Shalom EO offers Calcium Fluoride Windows with protective coatings and assembled windows with metal holders. Our CaF2 windows serve as capable components for spectroscopes or fluorescence imaging/ thermal imaging, the uncoated window substrates are excellent for excimer laser.
Curves:
Transmission curve of the CaF2 windows of different thickenss
%20Windows11.jpg)
 Windows10-500x400.jpg)
 Windows10-50x40.jpg)