Germanium (Ge)

There is currently a global trade shortage of Germanium so we highly recommend our Chalcogenide glass for your infrared applications.

Germanium 1

Germanium (Ge) is a chemical element used extensively in optics, especially in the infrared (IR) part of the spectrum. Ge has a high refractive index (around 4.0 in the infrared region), making it highly effective in manipulating light in optical systems. It is transparent to infrared light, particularly in the 2-14 micrometer range, making it ideal for IR applications. Ge maintains its optical properties over a wide temperature range, which is important for applications requiring consistent performance under varying environmental conditions.

Optical Properties

Refractive Index: 4.0034

Thermal Co-efficient of Refractive Index: 35 – 40 x 10-5

Transmission Range: 1.8 – 12.0 µm

Thermal Properties

Thermal Linear Expansion: 6.1 x 10-6 /°C at 20°C

Thermal Conductivity: 59.8 W m⁻¹ K⁻¹  at 273 K

Specific Heat Capacity 319 J Kg⁻¹ K⁻¹

Melting Point: 938.2 °C

Mechanical Properties

Density: 5.33 g/cc

Knoop Hardness: 780

Young Modulus: 102.7 GPa

Shear Modulus: 67 GPa

Poisson Ratio: 0.278

Wavelength (µm)Refractive Index (n)
2.0584.1020
2.1534.0919
2.3134.0786
2.4374.0708
2.5774.0609
2.7144.0562
2.9984.0452
3.3034.0369
4.2584.0216
4.8664.0170
6.2384.0094
8.6604.0043
9.7204.0034
11.044.0026
12.004.0023
13.024.0021
Germanium 3

Inquiry Form

Contact Form

We suggest using your organization's email with its own domain (if any).

Scroll to Top