The thickness of a true zero order quartz plate is very thin, it is very easily damaged. In order to solve this problem, we can cement the thin quartz plate on a BK7 substrate to increase the strength.
| Material | Crystal Quartz+BK7 |
| Diameter Tolerance | +0-0.2mm |
| Surface quality | 20-10 |
| Wavefront Distortion | <λ/8@632.8nm |
| Clear Aperture | >90% |
| Parallelism | <1 arc second |
| Retardation Tolerance | <λ/300 |
| Coating | R<0.25% @central wavelength |
| Damage Threshold | >500mJ/cm2, 20ns, 20Hz@1064nm |
| * Remark：Customized is available | |
