Michael and Yuhang

We checked filter cavity alignment yesterday. The pico-motor of PR/BS and END mirrors are moved. The movement of PR is to recover its reference on BS chamber. The movement of BS is to recover its reference in filter cavity transmission camera. The movement of END mirror is to recover the flash.

After these movement, we checked the oplev spectrum as attached in this elog. They look fine. So this time, no touching issue of mirror was found.