Main type：
Size range, limit deviation
1. Radius of curvature SR:10~∞;
2, caliber D:φ20~φ200;
3, wall thickness T:≥1;
4, bow height H:≤SR2;
Technical index：
| Item | Normal | Precision | Ultra-precision |
| Surface shape（632.8nm） | 5λ | 5/2λ | λ |
| Irregularity△ | 1 | 1/2 | 1/4 |
| Surface defect | 80/50 | 60/40 | 40/20 |
| Surface roughness（nm） | 1.5~2.5 | 0.5~1.5 | < 0.5 |
| Edge thickness difference | 0.05 | 0.02 | 0.01 |
| Wall thickness uniformity | 0.10 | 0.05 | 0.02 |
| C-axis deviation | ≤5° | ≤2° | ≤0.5° |
| Center deviation | 5′~ 2′ | 2′~ 1′ | ≤ 1′ |
| Crystal orientation | C, A, and M are optional | ||
| Transmittance | >85% at 632.8nm | ||
Timber：
Sapphire, magnesium fluoride, germanium, silicon, quartz glass, optical glass, etc. can be selected according to requirements.
Order goods ：
Other specifications and precision products can be processed according to customer needs.