Accurate target-plane focal-spot characterization in high-energy laser systems using phase retrieval Kruschwitz, B. E. ; Bahk, S. -W. ; Bromage, J. ; Moore, M. D. ; Irwin, D. Abstract Publication: Optics Express Pub Date: September 2012 DOI: 10.1364/OE.20.020874 Bibcode: 2012OExpr..2020874K