25mm Dia x 25mm FL Uncoated, Ge Aspheric Lens

Product Details Diffraction Limited Performance Variety of Coating Options Full Prescription Data Available Due to material supply chain disruptions with germanium, there may be increased lead times and price changes on our germanium products. For more information, please contact our customer service team . Edmund Optics has limited remaining inventory of this part number and no raw material available to supply more once this is depleted. Please contact our Product Support Engineers to help with an alternate solution for your needs. Customer Service can provide you the latest price and availability. TECHSPEC Germanium Infrared (IR) Aspheric Lenses provide diffraction-limited focusing performance over a broad spectral range in the Mid and Long Wave infrared regions. Ideal for monochromatic light sources, such as quantum cascade lasers, these lenses offer a high-performance alternative to standard plano-convex lenses. The lenses are available in a 12.5, 25, or 50mm diameter. TECHSPEC Germanium Infrared (IR) Aspheric Lenses are available uncoated, or with BBAR coating options. Uncoated germanium has transmission of <50%, so custom anti-reflection (AR) coatings should be considered if specifying an uncoated lens. Each BBAR coated lens offers >95% transmission, making it ideal for integration into a variety of OEM applications. For custom design or coating options, please contact our Sales Department . Specifications General Type: Aspheric Lens Physical & Mechanical Properties Diameter (mm): 25.00 +0.0/-0.1 Center Thickness CT (mm): 3.45 ±0.10 Edge Thickness ET (mm): 2.32 Clear Aperture CA (mm): 22.5 Centering (arcmin): ≤5 Shape of Back Surface: Concave Edges: Diamond Turned Bevel: Protective as needed Optical Properties Effective Focal Length EFL (mm): 25.00 @ 4000nm Back Focal Length BFL (mm): 22.51 Substrate: Many glass manufacturers offer the same material characteristics under different trade names. Learn More Germanium (Ge) f/#: 1.00 Numerical Aperture NA: 0.50 Index of Refraction (n d ): 4.002 @ 11µm Coating: Uncoated Wavelength Range (nm): 2000 – 14000 Focal Length Specification Wavelength (nm): 4000 Aspheric Design Wavelength (nm): 4000 Surface Quality: 60-40 Radius R 2 (mm): 37.8 Asphere Figure Error, RMS @ 632.8nm: λ/6 Conjugate Distance: Infinite Material Properties Coefficient of Thermal Expansion CTE (10 -6 /°C): 6.1 Regulatory Compliance Certificate of Conformance: View ×