Ge Lens

Germanium (Ge) is in the range of 2-12 μm. Germanium is the most commonly used for making optical lenses and optical windows in high-efficiency infrared imaging systems. Due to the wide transmission range and opacity of visible light, Germanium is very suitable for infrared lasers and optical systems for the manufacture of optical components. Germanium’s high refractive index and minimal surface curvature make it an ideal material for making low-power imaging systems. The small color difference often eliminates the need for correction.

The absorption of Germanium increases with temperature. The obvious transmission degradation of Germanium material starts at about 100 ℃, and accelerates the degradation between 200 ℃ and 300 ℃, which may lead to catastrophic failure of the optical fiber. Due to the high reflectivity of the substrate surface, AR coated or DLC coated are widely used on Germanium’s surfaces.