Bi-refringent Filters (BIR)
- Optical axis is parallel to the plane surface.
- For laser resonator use
Birefringent filters are used in laser resonators to tune the laser wavelength. They consist of one or more plano-parallel quartz plates whose optic axis is parallel to the plane surface.
| Material: | Crystal Quartz |
| Surface Quality: | <20/10 |
| Transmitted Wavefront: | <λ / 10 |
| Diameter Tolerance: | < ± 0.20 mm |
| Thickness Tolerance: | <± 0.02 mm |
| Clear Aperture: | >85% of central dimension |
| Parallelism: | <5 arc sec |
