MgF2
Description:
Magnesium Fluoride (MgF2 crystal) is a birefrigent material crystal with excellent physical and chemical properties. It is used for optical elements where extreme ruggedness and durability is required.
Applications:
VUV and excimer laser windows, polarizers, and lenses;
Supplied with the optic axis cut perpendicular to the window faces.
Physical Properties:
| Lattice constant | a=4.621A; c=3.053A |
| Mohs hardness | 6 |
| Melting Point | 1255℃ |
| Density | 3.18g/cm3(at 291K) |
| Transparence range | 0.12 - 8.5mm |
| Thermal conductivity | 0.0075W/m/K |
| Expansion coefficient | aa=13.7x10-6/K; ac=8.48x10-6/K |
| Elastic Coefficients | C11=140.2 C12=89.5 C44=56.8 |
| C33=204.7 C13=62.9 C66=95.7 | |
| Apparent Elastic Limit | 49.6 MPa (7200 psi) |
| Poisson Ratio | 0.276 |
Optical Properties:
| Transparence range | 0.12-8.5mm |
| Absorption Coefficient | 40 x 10-3 cm-1 at 2.7 |
| Reflection Loss | 5.2% at 0.6 microns (2 surfaces) |
| Restrahlen Peak | 20 |
| dN/dT | 2.3 (parallel) & 1.7 x 10-6 (perp) at 0.4 |
| dN/d | = 0 14 |
Transmission Curve:
