Ge plate Diameter Tolerance:+0, -0.1mm Surface Quality: 60-40 scratch and Surface Figure: :lambda/2 at 632.8nm Ge plateSpecifications: Ge windowsMaterial:GeDimension Tolerance:+0.0, -0.1mmThickness Tolerance:± 0.1mmSurface quality:60/40Clear Aperture:>85%Flatness:λper 25mmParallelism:3' Bevel:<0.25mm X 45°Coating:Upon requirement Ge plate