Germanium Lenses (Ge Lenses) are prevalently applied in IR imaging systems in the 2 µm to 16 µm spectral range, incorporated in the LWIR (8-12μm) and MWIR (3-5μm) thermal imaging applications involving harsh conditions. The lenses are made from single-crystalline Germanium which is inherently transparent to IR light, after being coated with AR coatings, the transmission rate could be further optimized. Because Ge lenses do not transmit Visible and UV light, Germanium could also be processed into IR-transmitting windows, and domes.
Germanium Lenses features a high refractive index in the IR range (4.0026 at 11 μm), in fact, its refractive index is the highest among other common IR transmitting materials, while forming images, it demonstrates low chromatic aberration. This feature implies better focusing functions of the lenses, and makes them ideal for manifolds of applications.
Germanium is also more mechanically robust than other IR materials, but one side effect worth noting is that its transmission in the IR spectrum will shrink when the temperature goes up, operation temperature above 100 Celsius could be severely hindering to the efficiency of the optical system, a problem attributes to the innate property of the material that the AR coatings could not compensate.
Hangzhou Shalom EO provides Germanium Lenses of various forms including plano-convex, plano-concave, double convex, double concave, and meniscus lenses of spherical surfaces, or aspheric lenses. The maximum size capability is up to 300mm, with other custom dimensions to accommodate customers. The lens blanks are uniformly manufactured through CNC machining systems, the aspheric modules are further processed using the SPDT (Single Point Diamond Turning) technology to minimize the machining deviation, and afterward tested using Zygo interferometer, spectrophotometer, and profilometer to ensure tight geometric tolerances. Coating options are also abundant, compassing AR coating, DLC (Diamond, or Diamond Like Carbon) coating to strengthen the components, and Broadband AR coating, the coatings could be arbitrarily matched on the surfaces.
Features：
- Maximum diameter 300mm
- Broad wavelength range covers 2μm to 14μm
- Fit for both MWIR (3-5micro) and LWIR (8-12 micro)
- Aspherical surface lenses by SPDT offered
- Coating options: DLC coating, AR@3-5μm, AR@8-12μm, BBAR@3-12μm, and custom
