BaF2 Window
Barium Fluoride (BaF2) Windows can be used in a variety of applications, such as infrared spectroscopy, due to their wide broadband transmission that extends from the deep ultraviolet to the long-wave infrared. Barium fluoride’s low index of refraction of 1.48 provides high transmission without the need for anti-reflection coatings. Barium fluoride windows can be used up to 800°C in a dry environment, but prolonged exposure to moisture can degrade transmission in the vacuum ultraviolet range. While barium fluoride windows are less resistant to water than calcium fluoride, BaF2 windows are the most resistant optical fluoride to high-energy radiation, but feature lower UV transmittance. BaF2 has a Knoop hardness of 82.
Description
Parameter
Description
Advantages
1 ) Excellent Transmission from 200nm – 12μm
2 ) Resistant to High-Energy Radiation
3 ) Provide High Transmission without AR Coatings
Specifications
1 ) Diameter: 3~200mm
2 ) Diameter Tolerance: +/-0.2mm
3 ) Thickness Tolerance: +/-0.03mm
4 ) Aperture: >90%
5 ) Surface Quality: 80/50~10/5 (S/D)
6 ) Parallelism: <1 arc minute
7 ) Chamfer: 0.3-0.5mmx45°
Parameter
Advantages
| Optical Properties | |
|---|---|
| Transmission Range | 0.15 to 12 micron |
| Refractive Index | 1.45 at 5 micron |
| Refractive Loss | 6.5% at 5 micron |
| Crystal/Class Structure | Cubic CaF2 |
| Cleavage Plane | (111), Perfect |
| Mechanical Properties | |
|---|---|
| Density | 4.89 g/cc |
| Hardness(Knoop) | Knoop 82 with 500g indenter |
| Youngs Modulus | 53.07 GPa |
| Shear Modulus | 25.4 GPa |
| Bulk Modulus | 56.4 GPa |
| Poisson Ratio | 0.343 |
| Elastic Limit | 26.9 Mpa (300psi) |
| Molecular Weight | 175.36 |
| Thermal Properties | |
|---|---|
| Thermal Expansion | 18.1×10－6/℃ at 273K |
| Thermal Conductivity | 11.72 W m－1K－1 at 286K |
| Melting Point | 1386 ℃ |
| Specific Heat Capacity | 410 J Kg－1K－1 |
Technical Images
