50mm Diameter VIS-NIR Coated, Ultra-Thin N-BK7 Window

Product Details Ultra-Thin 0.20mm Thickness Precision N-BK7 Substrate Extremely Lightweight TECHSPEC Ultra-Thin N-BK7 Windows are our thinnest windows available and are at least 1/10 the thickness of our traditional N-BK7 windows. Their extremely thin designs make them ideal for both weight and size-sensitive applications. Additionally, their high tolerance design yields minimal beam distortion and scatter. TECHSPEC Ultra-Thin N-BK7 Windows are available uncoated or with a MgF2 anti-reflection coating. For custom sizes or coating options, please contact our Sales Department . Note: The Ultra-Thin N-BK7 Windows are very fragile. Handle these windows with care. Specifications General Type: Protective Window Type of Window: Glass Physical & Mechanical Properties Clear Aperture CA (mm): 45.00 Diameter (mm): 50.00 +0.00/-0.10 Thickness (mm): 0.20 ±0.025 Bevel: Protective as needed Edges: Fine Ground Parallelism (arcsec): <30 Poisson's Ratio: 0.21 Young's Modulus (GPa): 82 Knoop Hardness (kg/mm 2 ): 610.00 Optical Properties Coating: VIS-NIR (400-1000nm) Substrate: Many glass manufacturers offer the same material characteristics under different trade names. Learn More N-BK7 Index of Refraction (n d ): 1.516 Surface Quality: 40-20 Transmitted Wavefront, P-V: λ/2 Abbe Number (v d ): 64.17 Coating Specification: R abs ≤0.25% @ 880nm R avg ≤1.25% @ 400 - 870nm R avg ≤1.25% @ 890 - 1000nm Wavelength Range (nm): 400 - 1000 Damage Threshold, By Design: Damage threshold for optical components varies by substrate material and coating. Click here to learn more about this specification. 5 J/cm 2 @ 532nm, 10ns Material Properties Density (g/cm 3 ): 2.51 Coefficient of Thermal Expansion CTE (10 -6 /°C): 7.1 (-30 to +70°C) 8.3 (+20 to +300°C) Regulatory Compliance RoHS 2015: Compliant × Certificate of Conformance: View × Reach 235: Compliant ×