50mm Dia. x 1mm Thick, 3-5μm AR Coating, Ge Window

Product Details Uncoated or with AR Coatings Designed for a Variety of IR Ranges Minimal Chromatic Aberration Due to Low Dispersion Ideal for Infrared Applications Requiring Rugged Optics DLC Coated Germanium Windows are also 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 (Ge) Windows are available off-the-shelf with three anti-reflection coating options: 3 – 5μm for mid-infrared applications, 3 – 12μm for broadband multispectral applications, or 8 – 12μm for thermal imaging applications. Due to its high index of refraction (around 4.0 from 2 – 14μm), an anti-reflection coating is recommended on these germanium windows for sufficient transmission in the region of interest. Germanium is subject to thermal runaway, meaning the transmission decreases as temperature increases. As such, TECHSPEC Germanium (Ge) Windows should be used at temperatures below 100°C. Germanium’s high density (5.33 g/cm3) should be considered when designing for weight-sensitive systems. The Knoop Hardness of germanium (780) is approximately twice that of magnesium fluoride, making it ideal for infrared applications requiring rugged optics. Specifications General Type: Protective Window Type of Window: Crystal Physical & Mechanical Properties Clear Aperture CA (mm): 45.00 Diameter (mm): 50.00 +0.0/-0.1 Thickness (mm): 1.00 ±0.1 Parallelism (arcmin): <1 Dimensional Tolerance (mm): +0.0/-0.1 Bevel: Protective as needed Clear Aperture (%): 90.00 Edges: Fine Ground Poisson's Ratio: 0.28 Young's Modulus (GPa): 102.7 Knoop Hardness (kg/mm 2 ): 780.00 Optical Properties Coating: BBAR (3000-5000nm) Substrate: Many glass manufacturers offer the same material characteristics under different trade names. Learn More Germanium (Ge) Index of Refraction (n d ): 4.002 @ 11µm Surface Quality: 60-40 Coating Specification: R avg <3% @ 3 - 5μm Wavelength Range (nm): 3000 - 5000 Surface Flatness (P-V): λ/10 @ 10.6μm Material Properties Density (g/cm 3 ): 5.33 Coefficient of Thermal Expansion CTE (10 -6 /°C): 6.1 Regulatory Compliance RoHS 2015: Compliant × Certificate of Conformance: View × REACH 241: Compliant ×