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The BK-7 windows are designed to be used in precision optical systems. The optical transmission is high with little or no distortion of the transmitted signal.
Reynard Corporation standard parameters apply:
Substrate Material: BK-7
Surface Quality: 60-40 Scratch & Dig
Diameter Tolerance: +/- 0.25mm
Thickness Tolerance: +/- 0.2mm
Edges: Ground & Beveled
Wavefront Distortion: At 632.8nm over 80% of aperture
