Specifications Material: BK7 grade A optical glass Diameter Tolerance: +0.0, -0.15mm Thickness Width, length tolerance: ± 0.1mm Clear Aperture: >90% Parallelism: 1 minute Surface Quality: 40-20 scratch and dig Wavefront...[more]

    Specifications Material: BK7 grade A optical glass Diameter Tolerance: +0.0, -0.1mm Thickness Tolerance: ± 0.2mm Clear Aperture: >80% Parallelism: 1' Surface Quality: 60-40 scratch and dig Wavefront Distortion: l per 25mm...[more]