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Germanium Windows

Germanium windowsGermanium (Ge) is a relatively hard, high-density, IR transmitting material that blocks UV and VIS wavelengths but allows IR from 2µm. Germanium has the highest refractive index of commonly available IR-transmitters and has low optical dispersion. This makes it desirable in aspects of lens design where its refractive index allows otherwise impossible specifications to be built. AR coating is recommended.

Knight Optical stock a range of Germanium Windows DLC/AR coated for 7-12 µm, we can also offer custom Germanium windows to your specific requirement. Germanium custom windows can be manufactured from 5mm-300mm dia with a thickness up to 50mm.  A range of DLC/AR coatings are available including most common thermal imaging wavelength of 7-12 µm a range.  Form error of better than 0.5 waves can be achieved with parallel tolerances of 5 arc minutes.  For high quality imaging applications we can offer better than 20-10 scratch dig. Other Germanium components we can also offer are, Germanium lenses, Germanium prisms, and Germanium blanks to your specification for a range of applications. Every component is individually tested by our highly skilled technicians in our state of the art metrology lab to ensure all components meet our high quality standards

Typical applications for Germanium include thermal imaging where the material can be used as a front optic while its index of refraction makes Germanium useful for wide-angle lenses and microscopes. Additionally, Germanium components can be used for FLIR (Forward Looking Infrared) and FTIR (Fourier Transformed Infrared) spectroscopy systems, alongside other analytical.

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Our stock range of germanium windows can be edged down at short notice for your custom application, please enquire.

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