EOM installed

Today when we tried to install the EOM, we found out since the telescope changed, the beam size at EOM input is a little bit large. The EOM should be installed between the second lens and the MZ, and we still need some space for another mirror and beam splitter of MZ. So we checked the optical scheme and found out there is enough space to push the MZ further from the lens. We pushed the MZ three holes back and installed the EOM.

Then the beam size changed a lot at the PR window and also it seems diverge very quickly after the BS suspension. We checked the manual of the EOM, did not find anything about this situation. For better understanding what happened to the beam after the EOM, we removed the third lens, take a few measurement before the EOM and after the EOM. Then did the fitting to check what changes. The origin set as the line of hole near the second lens. From the figure it seems only the beam waist shift from 27.2 to 20.2, the beam waist size changed a bit, but we should consider that the space is limited, so we need to take several points of measurement which is quiet close to each other. Also the z value is measured with meters which is not very precise. It seems this problem can be solved only with moving the third lens.