150mm Dia., 4mm Thick, Uncoated, B270 Window

Product Details Large Selection of Sizes Available Uncoated, MgF2, or VIS-NIR Anti-Reflection (AR) Coated Custom Sizes Available for Volume OEM Requirements TECHSPEC B270 Windows offer a high transmission from the visible to the near-infrared (NIR). They have a similar refractive index to N-BK7 while being more cost-effective. These windows are often used as a protective element due to their high solarization stability and chemical resistance, making them ideal for standard window applications. TECHSPEC B270 Windows are available either uncoated or coated with a MgF2 or VIS-NIR Anti-Reflection (AR) Coating. Both circular and square options are offered in various sizes, and custom sizes and coatings are available for OEM applications. Specifications General Type: Protective Window Type of Window: Glass Physical & Mechanical Properties Clear Aperture CA (mm): 135.00 Diameter (mm): 150.00 +0.00/-0.25 Thickness (mm): 4.00 ±0.20 Bevel: Protective as needed Edges: Fine Ground Poisson’s Ratio: 0.22 Young’s Modulus (GPa): 71.5 Knoop Hardness (kg/mm 2 ): 500.00 Optical Properties Coating: Uncoated Substrate: Many glass manufacturers offer the same material characteristics under different trade names. Learn More B270 Index of Refraction (n d ): 1.523 Surface Quality: 60-40 Abbe Number (v d ): 58.3 Wavelength Range (nm): 360 – 2700 Surface Flatness (P-V): 1λ (per 25.4mm Dia. within CA) Material Properties Density (g/cm 3 ): 2.56 Coefficient of Thermal Expansion CTE (10 -6 /°C): 9.4 (+20 to +300°C) Regulatory Compliance RoHS 2015: Compliant × Certificate of Conformance: View × Reach 247: Compliant ×