sentences:  Here it is reflected off a series of deformable mirrors that help correct remaining imperfections in the wavefront, and then feeds them into the target chamber from all angles.Since the overall distances from the ends of the beamlines to different points on the target chamber are different, delays are introduced on the individual paths to ensure they all reach the center of the chamber at the same time, within about 10 picoseconds (ps).The target, a fusion fuel pellet about 1 mm in diameter in the case of HiPER, lies at the center of the chamber.