Kruschwitz B E, Bahk S-W, Bromage J, Moore M D, Irwin D
University of Rochester Laboratory for Laser Energetics, 240 E. River Rd., Rochester, New York 14623, USA.
Opt Express. 2012 Sep 10;20(19):20874-83. doi: 10.1364/OE.20.020874.
Target-plane intensities on the short-pulse beamlines of OMEGA EP, a petawatt-class laser, are characterized on-shot using the focal-spot diagnostic (FSD), an indirect wavefront-based measurement. Phase-retrieval methods are employed using on-shot and offline camera-based far-field measurements to improve the wavefront measurements and yield more-accurate, repeatable focal-spot predictions. Incorporation of these techniques has improved the mean cross-correlation between the FSD predictions and direct far-field fluence measurements in the target chamber from 0.78 to 0.94.
