| Substrate: |
Schott B270 glass |
| Outer Diameter: |
25.4,-0.2/+0.0mm |
| Thickness: |
3.0,+/-0.1mm |
| Surface Quality: |
Double side fine polished (40-20 scratch and dig, MIL Standard) |
| Clear Aperture: |
>80% of outer diameter |
| Flatness: |
< Lambda/10 @ 632.8nm over clear aperture on-jig tested |
| Surface Coating: |
Amorphous silicon coating layer, thickness 150+/-10nm
SiO2 buffer layer 5-10nm, to enhance the adhesion of over coating with glass(SiO2) |
| Back Surface: |
Polished/uncoated |
| Edge Surface: |
Ground, with protection chamfer 0.3mm x 45deg | |