Guided by laser mirrors (LMs 1, 2, and 3), each beam zooms through two large glass amplifiers, first through the power amplifier and then into the main amplifier. The 48 beams are then split into four beams each for injection into the 192 main laser amplifier beamlines. At the outset of a NIF experiment, a weak laser pulse-about 1 billionth of a joule-is created, split, and carried on optical fibers to 48 preamplifiers that increase the pulse’s energy by a factor of 10 billion, to a few joules.
