Crystals Materials
Germanium (Ge) be used for windows, infrared optical lenses (spherical and/or non-spherical), prisms, and other optical components.
Chalcogenide glasses, also known as infrared glasses or germanium glasses, possess excellent optical transparency, minimal refractive index and thermal dispersion changes. Within the range of 1-14μm, germanium glass exhibits minimal thermal defocusing, making it easier to design color-corrected infrared optical systems. It is an ideal choice for applications that require combining with other infrared materials. Germanium glass can be used for windows, infrared optical lenses (spherical and/or non-spherical), prisms, and other optical components.
| Material | Germanium (Ge) |
| Diameter | 3mm ~ 300mm |
| Thickness | >0.1mm |
| Dimension Tolerance | +0/-0.02mm |
| Angle Tolerance | ±15 arcsec |
| Surface Accuracy | λ/10 @ 633nm |
| Surface Quality S/D | 10–5 |
| Pyramid Tolerance | <5 arcmin |
| Bevel | <0.25mm X 45° |
| Coating | Available upon request |
| Crystal Structure | Cubic |
| Density | 5.27 g/cm³ |
| Crystal Size | <100 μm |
| Impurities | None > 0.05 mm |
| Resistivity | > 10^12 ohm-cm |
| Dielectric Constant | Consult Technical Personnel |
| Absorption Coefficient @10.6μm | <0.0005 cm^-1 |
| Thermal Optical Coefficient (dn/dT) @10.6μm | 6.1 × 10^-5 ℃ |
| Refractive Index Uniformity @0.6328μm | <3 × 10^-6 |
| Thermal Conductivity @20°C | 0.18 W/cm/℃ |
| Specific Heat | 0.356 J/g/℃ |
| Linear Expansion Coefficient @20°C | 7.57 × 10^-6/℃ |
| Young's Modulus | 67.2 GPa (9.75 × 10^6 psi) |
| Fracture Modulus | 55.1 MPa (8,000 psi) |
| Knoop Hardness | 105-120 kg/mm² |
| Poisson's Ratio | 0.28 |
| Fracture Toughness | 0.5 × 10^6 N/m^3/2 |
Stock specification list
If need other specifications and quantities products, please contact us(sales@aogcrystal.com).
Anti-reflection coatings are available at your specified wavelength.
Be sure to wear laser safety goggles when checking optical path and adjusting optical axis.
To inquiry or order a finished Germanium (Ge) windows, please specify the specification listed above, for common application, we only need to know the main specification: Cr-dopant concentration, sizes, and coating. For special
request, please specify specification in details for evaluation and fabrication.
| Part Number | Face size | Thickness | Surface Quality | Coating |
|---|---|---|---|---|
| WIN-080-020-Ge | Dia 8.00 mm | 2.00 mm | 40/20 | UnCoated |
| WIN-127-020-Ge | Dia 12.70 mm | 2.00 mm | 40/20 | UnCoated |
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