OUTSIDE THE LASER ENCLOSURE
The structure of interest in this panorama is the walled enclosure that sits in front of the scientist. Note that it consists of two portions, a lower metal-framed portion to the right and a taller conventional-walled portion to the left. Inside the right-hand portion is a gowning room and some laboratory space. Inside the tall portion rests another walled structure -- a room within a room. Inside this secondary clean room sits the 20-foot laser table that holds LIGO Hanford's pre-stabilized laser system (PSL). To the left of the scientist in the panorama, viewers can see a large schematic diagram of the PSL attached to the wall. The layout of the PSL from left to right is the reverse of what's indicated in the schematic.
Several racks of PSL controls occupy the left view of the panorama. These racks block your view of the beam splitter chamber that sits dozens of meters away. The H1 detector's input optics occupy the beam path between the PSL enclosure and the beam splitter. Optics in the input chambers perform additional purification of the light from the PSL and participate in the power recycling of the main beam to boost the light levels in the main interferometer.