Commercial Quality Windows, Square, N-BK7 Optical Glass

Esco PN:
  • $ 1634

Diameter Tolerance

+/- 0.125 mm

Thickness Tolerance

+/- 0.125 mm

Surface Accuracy

1.0-3.0 mm thickness ≤ 5λ per inch
4.76-12.7 mm thickness ≤ 2λ per inch

Surface Quality

60-40 Scratch-Dig or better




Fine ground and safety beveled*

Clear Aperture


*parts under 25.4mm in diameter may not have beveled edges

Commercial windows are used for sight glasses, instrument windows, beamsplitter substrates, vacuum windows, welding window substrates. Esco carries a complete inventory of square commercial optical windows of N-BK-7 Optical Glass.

Would you like to modify a catalog part to better suit your requirements? Please use our online quote tool to get an estimate on a custom part.  


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ITAR Registered & Compliant

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