Barium Fluoride (BaF₂) Optical Windows

Barium Fluoride (BaF₂) Optical Windows / IR Windows / BaF₂ Polished Substrates

Product Overview
Barium Fluoride (BaF₂) optical windows are infrared optical components featuring transmission from deep ultraviolet to infrared wavelengths. With optical uniformity, thermal stability, and mechanical properties, BaF₂ windows are used in infrared spectroscopy, thermal imaging, laser systems, and optical instrumentation. Double-side polishing is used for optical research and industrial applications.

Optical & Physical Properties
Material: Barium Fluoride (BaF₂)
Crystal Structure: Single Crystal
Transmission Range: 0.15 – 12.5 μm
Refractive Index: 1.4626 @ 2.58 μm
Transmittance: >90% (0.35–9 μm, 3 mm thickness)
Density: 4.89 g/cm³
Melting Point: 1368 °C
Thermal Expansion Coefficient: 18.1 × 10⁻⁶ /°C
Young’s Modulus: 56.4 GPa
Hardness (Knoop): 82 (500 g load)
Solubility in Water: 0.17 g/100 g @ 23 °C
Cleavage Plane: (111)

Optical Specifications
Surface Quality: 60-40 scratch-dig
Surface Flatness: λ/4 @ 633 nm
Parallelism: High precision polished
Clear Aperture: >90%
Diameter Tolerance: +0 / -0.1 mm
Thickness Tolerance: ±0.1 mm
Edge: Protective bevel
Coating: Uncoated standard; AR coating optional

Key Features
Wide transmission range from UV to IR
High infrared transmittance (>93%)
thermal and mechanical stability
Low absorption and good optical uniformity
construction and moisture resistance
Precision double-side polishing
Custom sizes and thickness available

Typical Applications
Infrared optical windows
FTIR and spectroscopy systems
Thermal imaging systems
Gas sensing and environmental monitoring
Laser and optical instruments
Vacuum and detector windows
General optical research

Packaging
Cleanroom packed
Vacuum-sealed protective packaging
Individual box packaging for transport

Customization
Custom diameter, thickness, and surface finish available upon request
AR coating and special optical coatings available