Sapphire Windows

      Materical
      Orientation
      Diameter Tolerance
      Thickness Tolerance(h)
      Surface Quality
      Parallelism
      Clear Aperture
      Wavefront Distortion
      Protective Bevel

Anisotropic synthetic sapphire crystal (Al₂O₃)
Random
+0.0/-0.1mm
+/-0.2mm
120-80 scratch and dig
3 arc minutes
>80%
2λ per 25mm @632.8nm