General requirement
RP requires attenuation to XX mJ.
Pre-2022 RP attenuator
Currently installed
4 mirrors and thin-film polarisersÂ
p-pol as input
Issues:
- Appears to introduce astigmatism
- Ghosts when changing polarisation
2022 RP attenuator
4 mirrors and s-pol as input.
Mirrors are 35%R from MPO, AR coating on back and 2 degree wedge.
Reflectivity was tested:
Wedge orientation:
Quote for mirrors: