A picosecond timing system for the LIL laser facility

The CEA has studied a unique picosecond timing system for the Laser Integration Line (L.I.L.), an 8-beam laser currently under construction in France. This laser is the prototype of a future facility dedicated to inertial confinement fusion. It requires very precise timing between its laser beams and ultra-fast diagnostics. Its timing system had to achieve unprecedented performances : to deliver 800 trigger signals over distances exceeding 300 in with delays individually programmable and near-picosecond range time accuracy. To achieve this goal, the CEA developed a new design based on very accurate electrical delay generators connected to a master clock through a bi-directional fiber-optic time distribution network. In this article, we describe its principle and present achieved performances.