LiF Window
Lithium Fluoride(LiF) is used for windows, lenses and prisms in the Vacuum UV, UV, visible and infrared where transmission in the range 0.104µm to 7µm is desired. Transmission is about 40% at 121nm. LiF is attacked by atmospheric moisture at 400C, and softens at 600C. LiF is sensitive to thermal shock. Irradiation produces color centers. The material can be cleaved along (100) and less commonly (110). Although the optical characteristics are good the structure is not perfect and cleavage is difficult. VUV grade LiF windows are available.
Description
Parameter
Description
Advantages
1 ) Excellent optical performance
2 ) Ideal for Applications Ranging from 120nm – 6μm
3 ) Good transmission in the VUV region
Specifications
1 ) Diameter Tolerance: +/-0.2mm
2 ) Thickness Tolerance: +/-0.03mm
3 ) Aperture: >90%
4 ) Surface Quality: 80/50~10/5 (S/D)
5 ) Parallelism: <1 arc minute
6 ) Chamfer: 0.3-0.5mmx45°
Parameter
Advantages
| Optical Properties | |
|---|---|
| Transmission Range | 0.12 to 6 micron |
| Refractive Index | 1.392 at 0.6 micron |
| Refractive Loss | 5.2% at 0.6 micron |
| Crystal/Class Structure | Cubic FCC, NaCl, Fm3m |
| Mechanical Properties | |
|---|---|
| Density | 2.64 g/cc |
| Hardness(Knoop) | 102 with 600g indenter |
| Youngs Modulus | 64.97 GPa |
| Shear Modulus | 55.14 GPa |
| Bulk Modulus | 62.03 GPa |
| Poisson Ratio | 0.326 |
| Elastic Limit | 11.2 Mpa (1620psi) |
| Molecular Weight | 25.94 |
| Thermal Properties | |
|---|---|
| Thermal Expansion | 37×10－6 K－1 at 283K |
| Thermal Conductivity | 58.61 W m－1K－1 at 293K |
| Melting Point | 936 ℃ |
| Specific Heat Capacity | 310 J Kg－1K－1 |
Technical Images
