MgF2
Density：3.18g/cm^3
Transmission：＞90%@0.11-7.5μm
Homogeneity：＜5×10^-6
Cleavage plane：<100>or <110>
| Size | Diameter | Dia.-Thick Ratio | Radius of curvature | Opening angle | ΔR | Surface Quality S/D | Flatness | ETV |
| Small | φ10-φ25mm | 5:1 | ≥35mm | ≤60° | A | 60-40 | N≤2 ΔN≤0.5 | 0.05 |
| Medium | φ25-φ100mm | 5:1 | ≥35mm | ≤60° | A | 60-40 | N≤2/φ60mm ΔN≤0.5/φ60mm | 0.05 |
| Large | φ100-φ200mm | 5:1 | ≥120mm | ≤60° | A | 80-50 | N≤2/φ60mm ΔN≤0.5/φ60mm | 0.05 |
