�� Specifications:
�� Material: BK7 or Fused Silica
�� Diameter Tolerance: +0,-0.2mm
�� Thickness Tolerance: +/-0.2mm
�� Clear Aperture: >80%
�� Flatness: ��/8@632.8
�� Parallelism: < 1 arc minute
�� Surface Quality: 20-10(Substrate), 40-20 (After Coating)
�� Surface 1: HR @wavelength-1 + HT @wavelength-2
�� Surface 2: AR @wavelength-2
�� Angle of incident: 0�� or 45��