Barium Fluoride (BaF2) Windows
Broad Transmission Range: High transmission from 0.2 µm to 11.0 µm, suitable for both UV and IR applications.
Low Refractive Index: ~1.48, ensuring high transmission rates without the need for anti-reflection coatings.
Radiation Resistance: More resistant to high-energy radiation compared to CaF2, making it suitable for harsh environments.
Thermal Stability: Can endure temperatures up to 800 °C when dry, although sensitive to moisture at higher temperatures.
Extended LWIR Transmission: Transmission range stretches about 1 micron further into the LWIR spectrum compared to CaF2.
Applications: IR spectroscopy, thermal imaging, UV applications, high-energy radiation environments, etc.
Barium Fluoride (BaF2) Windows from Kingwin Optics provide superior optical performance across a wide spectral range from the deep ultraviolet (UV) to the long-wave infrared (LWIR) (0.2-11.0 µm). These windows are particularly well-suited for infrared applications that also require UV transmission, making them versatile for various industries and research fields.
Key Properties of Barium Fluoride Windows:
| Materials | IR Grade Barium fluoride Crystals |
| Aperture | >90% |
| Dimension Tolerance | +0.0/-0.1mm |
| Thickness Tolerance | +/-0.2mm |
| Surface Quality | 60/40 S/D |
| Chamfer | 0.3-0.5mmx45degree |
| Transmission Range | 0.15 to 12 μm |
| Refractive Index | 1.45 at 5 μm (1) |
| Reflection Loss | 6.5% at 5 μm (2 surfaces) |
| Absorption Coefficient | 3.2 x 10-4cm-1 @ 6 μm |
| Reststrahlen Peak | 47 μm |
| dn/dT | -15.2 x 10-6 °C (2) |
| dn/dμ = 0 | 1.95 μm |
| Thermal Conductivity | 11.72 W m-1 K-1 @ 286 K |
| Melting Point | 1386°C |
| Hardness | Knoop 82 with 500g indenter (4) |
| Thermal Expansion | 18.1 x 10-6 /°C @ 273 K |
| Dielectric Constant | 7.33 at 1 MHz |
| Specific Heat Capacity | 410 J Kg-1 K-1 (3) |
| Density | 4.89 g/cc |
| Youngs Modulus (E) | 53.07 GPa (3) |
| Shear Modulus (G) | 25.4 GPa (3) |
| Bulk Modulus (K) | 56.4 GPa |
| Elastic Coefficients | C11 = 89.2 C12 = 40.0 C44 = 25.4 (2) |
| Apparent Elastic Limit | 26.9 MPa (300psi) (4) |
| Poisson Ratio | 0.343 |
| Solubility | 0.17g/100g water at 23°C |
| Molecular Weight | 175.36 |
| Class/Structure | Cubic CaF2, Fm3m, (111) , cleavage |
Advantages of Barium Fluoride Windows:
- Broad Transmission Range: High transmission from 0.2 µm to 11.0 µm, suitable for both UV and IR applications.
- Low Refractive Index: ~1.48, ensuring high transmission rates without the need for anti-reflection coatings.
- Radiation Resistance: More resistant to high-energy radiation compared to CaF2, making it suitable for harsh environments.
- Thermal Stability: Can endure temperatures up to 800 °C when dry, although sensitive to moisture at higher temperatures.
- Extended LWIR Transmission: Transmission range stretches about 1 micron further into the LWIR spectrum compared to CaF2.
Coating Options:
To further enhance the performance and durability of BaF2 windows, Kingwin Optics offers a variety of protective coatings:
- Anti-Reflection (AR) Coatings: To maximize transmission and reduce reflections.
- Custom Coatings: Tailored to specific wavelength ranges and application requirements.
Applications:
- IR Spectroscopy: Ideal for precise spectroscopic measurements across a broad spectral range.
- Thermal Imaging: Suitable as viewport windows for thermal imaging inspection in electric power facilities and petroleum industries.
- UV Applications: Effective in applications requiring UV transmission due to its extensive transmission range.
- High-Energy Radiation Environments: Resistant to high-energy radiation, making it suitable for use in challenging conditions.
Custom and Assembled Solutions:
Kingwin Optics provides custom Barium Fluoride Windows, including:
- Protective Coated Windows: For enhanced durability and performance.
- Assembled Windows with Metal Holders: For easy integration into optical systems.
- Detailed Handling Instructions: Due to the toxic nature of BaF2, handling instructions and safety measures are provided.
Barium Fluoride Windows from Kingwin Optics are designed to provide exceptional performance across a wide spectral range. With their broad transmission range, low refractive index, high radiation resistance, and thermal stability, these windows are ideal for a variety of applications, including IR spectroscopy, thermal imaging, and UV applications. Customizable dimensions and coatings ensure that your specific needs are met with precision and quality.
