Specification
| Retarder Material | Muscovite Mica |
| Substrate Material | N-BK7 |
| Transmitted Wavefront | <1 Lambda @ 633 nm for diam. 25.0 mm |
| Retardation Tolerance | /50 for 532 nm type |
| Homogeneity of Retardation | /200 |
| Thickness | 2.5 mm +/-0.25 mm |
| Clear Aperture | 85% of central diameter |
| Parallelism | <3 arc minutes |
| Surface Quality | 40-20 scratch dig |
| Reflectivity of AR-Coated (633 nm) Surfaces at Normal Incidence | < 0.5% average over 400 nm 700 nm |
| Damage Threshold, pulsed | 0.7 J/cm, 11 ns, 100 Hz @ 1064 nm |
| Damage Threshold, cw | 0.5 kw/cm @ VIS-NIR |
| Temperature Coefficient of Retardation per C | negligible |
| Standard Retardations | /4, /2 |
Standard Wavelengths (nm)
| 405 | 488 | 532 | 560 | 633 | 650 |
Special Wavelengths (nm) *)
| 442 | 448 | 515 | 543 | 589 | 670 | 780 |
| 830 | 850 | 904 | 1064 | 1300 | 1510 | 1550 |