Germanium (Ge)
High-index infrared semiconductor: opaque in the visible, highly transmissive through the LWIR. The reason thermal imaging lenses and defense optics keep coming back to it.
Flat optics material
Typical properties
- Transmission range
- 2 – 14 µm (opaque in the visible)
- Refractive index
- 4.0032 @ 10.6 µm
- Knoop hardness
- 780 kg/mm²
- Density
- 5.33 g/cm³
- Thermal expansion (CTE)
- 6.1 × 10⁻⁶ /K
Published values for this material class, given to help you shortlist a substrate. They are not lot-specific guarantees. Request the SPEKTON datasheet for certified figures against your specification.
Download Technical Datasheet (PDF)Datasheet referenced from Crystran.
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