[Terrence, Keiko]

Intermediate update: We are modifying the gouy phase telescope as suggested in the main post, and haven't finised yet. Two lens positions were changed, and the LSC PDs were re-centered. Tomorrow the beam profile of the new WFS paths will be measured.

One observation: the beam shape at the whole path is very dirty, as attached. This shape seems to be from the P-pol shape. So probably the profile cannot measured very precisely. We observed the shape after PBS, but the shape was almost the same.

Note: POP and POP-Ppol camera have light, but, as the gouy telescope changed, the beam size is quite large at the cameras. Some lens will be inserted tomorrow.