Barium Fluoride (BaF2)
Barium Fluoride (BaF2) optical material for UV-to-IR windows and spectroscopy optics, with local refractive-index reference data for engineering review.
Key Properties
Primary engineering references for material screening, packaging review, and RFQ preparation.
About Barium Fluoride (BaF2)
Overview
Barium Fluoride (BaF2) is usually selected for broadband windows, spectroscopy optics, and optical paths that need UV-to-IR coverage with a lower refractive index than ZnSe, Ge, or Si. For practical design work, the material should be reviewed against wavelength band, environment, coating target, and the mechanical fragility of the final part geometry.
Key Material Reference
| Parameter | Reference |
|---|---|
| Practical Transmission Guidance | 0.15-14.0 µm |
| Local RII Dataset Range | 0.2652-10.346 µm |
| Reference Dataset | Malitson formula 1, 25 °C |
| Refractive Index | 1.4510 at 5.0 µm |
| Density | 4.89 g/cm3 |
| Knoop Hardness | 82 kg/mm2 |
| Young's Modulus | 53.07 GPa |
| Thermal Expansion | 18.1 x 10^-6 /K @273 K |
Selected Refractive Index Reference
The refractive-index points below are page-level engineering references taken from the local RII dataset. Final optical modeling should still use the confirmed design wavelength range and temperature condition.
| Wavelength (µm) | Refractive Index |
|---|---|
| 0.300 | 1.5010 |
| 0.500 | 1.4778 |
| 1.000 | 1.4686 |
| 3.000 | 1.4612 |
| 5.000 | 1.4510 |
| 10.000 | 1.4013 |
Typical Applications
- Broadband spectroscopy windows and analytical optics
- UV-to-IR windows where a lower index substrate is preferred
- Beam path components for laboratory and measurement systems
- Custom crystal optics that need wide spectral coverage
Engineering Notes
BaF2 is usually reviewed when broad wavelength coverage is more important than high refractive power. Engineers should confirm whether the lower hardness, coating design, and storage environment fit the actual use case before freezing the drawing. Compare the broader materials index with the manufacturing options under products before assigning the final substrate.
Procurement Checklist
- Confirm the working band, especially if the design needs consistent response beyond the local reference dataset range.
- Specify diameter, clear aperture, center thickness, and quantity for every RFQ.
- State whether AR coating, uncoated delivery, or inspection-only blanks are required.
- Include operating environment details if the part will see humidity, cleaning cycles, or repeated handling.
Request Engineering Review
Send wavelength range, dimensions, coating target, quantity, and application notes through the contact page for a practical BaF2 material and manufacturability review.