25mm Dia x 50mm FL 3-5μm AR Coated, Si Aspheric Lens

Product Details Diffraction-Limited Performance Low Density and Dispersion Ideal for Weight Sensitive IR Applications Available with BBAR (1650-3000nm) or Mid-Wave Infrared (3000-5000nm) AR Coatings TECHSPEC Silicon Aspheric Lenses are high performance, lightweight solutions for BBAR and Mid-Wave Infrared (MWIR) applications and are ideal alternatives for costly ZnSe lenses and brittle Germanium lenses. These lenses are available with efficient broadband AR coatings for the BBAR (1650-3000nm) or MWIR (3000-5000nm) spectral regions. TECHSPEC Silicon Aspheric Lenses feature the mechanical and thermal properties required to withstand many of the effects of harsh environments including fluctuations in temperature and pressure. Because silicon is a low density material, these lenses are also ideal for weight-sensitive systems, such as those found in many defense applications. Specifications General Type: Aspheric Lens Physical & Mechanical Properties Diameter (mm): 25.00 +0.00/-0.10 Center Thickness CT (mm): 3.00 ±0.10 Edge Thickness ET (mm): 2.3 Clear Aperture CA (mm): 22.5 Centering (arcmin): ≤10 Centering, ETD (μm): <21.8 Shape of Back Surface: Concave Edges: Diamond Turned Bevel: Protective as needed Optical Properties Effective Focal Length EFL (mm): 50.00 @ 4000nm Back Focal Length BFL (mm): 47.78 Substrate: Many glass manufacturers offer the same material characteristics under different trade names. Learn More Silicon (Si) f/#: 2.00 Numerical Aperture NA: 0.25 Index of Refraction (n d ): 3.422 @ 5µm Coating: BBAR (3000-5000nm) Coating Specification: R avg <3% @ 3 - 5μm Wavelength Range (nm): 3000 - 5000 Focal Length Specification Wavelength (nm): 4000 Aspheric Design Wavelength (nm): 4000 Surface Quality: 60-40 Radius R 2 (mm): 75.698 Asphere Figure Error, RMS @ 632.8nm: λ/6 Surface Accuracy, P-V (μm): <0.3 Conjugate Distance: Infinite Material Properties Coefficient of Thermal Expansion CTE (10 -6 /°C): 2.55 Regulatory Compliance RoHS 2015: Compliant × Certificate of Conformance: View × REACH 241: Compliant ×