BK WindowsHigh Precision BK7 WindowsSpecifications: Material: BK7 grade A optical glass Diameter Tolerance: +0.0, -0.1mmThickness Tolerance: +/-0.05mmClear Aperture: >90%Parallelism: <10 arc secondsSurface Quality: 20-10 scratch and digFlatness: lambda /10 per 25mm at 633nmBevel: <0.25mm time 45degCoating: Upon requirementStandard BK7 WindowsSpecifications: Material: BK7 grade A optical glass Diameter Tolerance: +0.0, -0.1mmThickness Tolerance: +/- 0.2mmClear Aperture: >85%Parallelism: <1 arc minuteSurface Quality: 60-40 scratch and digFlatness:lambda/2 per 25mm at 633nmBevel: <0.25mm time 45degCoating: Upon requirement
