[Kambara, Hasegara, Akutsu]

The DC PD used for the initial alignment has moved to BS from EXA. Because the height of light beam from the optical table in the BS chamber differs from the one in the EXA chamber in a large amount, the combination of the PD and the pedestal cannot be used as is. Instead of this, we combined two shorter pedestals (dedicated for supporting some AOS optics in the vacuum encloses) that happend to exist there, and use it to support the DC PD in the BS chamber at a reasonable height.