This afternoon we investigated the losses due to FI on EQB1 bench. Using BAB (SC shuttered) we measured the power before and after FI:
before 1.42mW
after 1.40mW

so we have losses due to FI of about 1.4%.

Then, we have verified that the SC is not well aligned in the FI as we measure about 10% of power losses (before the FI and in transmission to it towards the OPO).

With only BAB, we also checked the power after the FI along the path to the HD, not measuring losses.