Germanium(Ge) Positive Meniscus Lenses, Uncoated/AR8~12μm
Germanium (Ge) Meniscus Lenses are precision optical components manufactured from single-crystal germanium substrate. A meniscus lens features one convex surface and one concave surface. A positive meniscus lens with a stronger convex curvature yields a positive focal length; when paired with other lenses, it shortens the focal length and increases the numerical aperture (NA) of the system without introducing significant spherical aberration. A negative meniscus lens is defined by a stronger concave curvature.
As a widely used infrared optical material, germanium offers a broad transmission range of 2.0–16 μm, high refractive index, and excellent Knoop hardness. Chemically inert to air, water, acids, and alkalis, germanium performs reliably in thermal imaging and infrared imaging systems operating in harsh environments. It serves as an ideal substrate for lenses, windows, and various infrared optical components.
Tuniu Optics provides germanium meniscus lenses in both uncoated and broadband anti-reflection (AR) coated versions optimized for the 8–12 μm (IR2) waveband, making them well suited for diverse infrared applications. Custom specifications are available to meet your unique requirements. For further inquiries or custom solutions, please contact us.
Note: Germanium contains hazardous substances. Always wear gloves when handling and wash hands thoroughly after use.
Parameters
| Material | Ge Single Crystal |
| Design Wavelength | 10.6 μm |
| Diameter Tolerance | + 0.0/ -0.1 mm |
| Center Thickness Tolerance | ± 0.2 mm |
| Focal Length Tolerance(EFL) | ± 1% |
| Centering Tolerance | < 3 arcmin |
| Surface Quality | 60-40 |
| Bevel | 0.2 mm x 45° |
| Coating | Uncoated, Ravg < 1.5%@8~12 μm |
Model
| Dia., mm | Coating | EFL, mm |
| φ25.00 | Uncoated/Double Sided AR coating @8~12 μm | 25.00/30.00/35.00 |
| φ50.00 | Uncoated/Double Sided AR coating @8~12 μm | 50.00/75.00/100.00 |

