Specifications

Diameter (mm): 40.0
CT (mm): 2.0
Specifications: Diameter (DIA): +/- .25
Center Thickness (CT): +/- 0.1
Cosmetics: 80/50
Surface Flatness: 1 wave per 25mm at 632.8nm
Parallelism: 3 arc minutes
Clear Aperture: 90% of diameter
Material: Anisotropic crystalline synthetic Sapphire (Al2O3)
Crystalline Optic Axis Orientation: Uncontrolled
Birefringence: The difference between ordinary and extraordinary indices shall be
0.008 for visible light in directions orthogonal to the optical axis.
Stress Birefringence: 0.1 fringe per mm thickness at 632.8nm and 2.43Kg/cm2
All dimensions are in millimeters.