| Material | optical glass,N-BK7 , Fused Silica, sapphire,Si,Ge,CaF2,LiF,BaF2,Znse,ZnS,chalcogenide glass |
| Dimensions | 3-400mm |
| Dimension Tolerance | ±0.01mm |
| Thickness Tolerance | ±0.01mm |
| Center thickness | >1mm |
| Focal Length tol. | ±1% |
| Centration | 3 arc minutes |
| Surface Quality | 80/50 60/40 40-20 20-10 |
| Clear Aperture | >90% |
| Bevel | Protective bevel as needed |
| Coating | as per your request |