Programmable focal spot shaping of amplified femtosecond laser pulses.
We describe the programmable spatial beam shaping of 100-kHz, 4-microJ amplified femtosecond pulses in a focal plane by wave-front modulation. Phase distributions are determined by a numerical iterative procedure. A nonpixelated optically addressed liquid-crystal light valve is used as a programmable wave-front tailoring device. Top-hat, doughnut, square, and triangle shapes of 20-microm size are obtained in a focal plane. Their suitability for femtosecond laser machining is demonstrated.
Sanner
Nicolas
N
Laboratoire Traitement du Signal et Instrumentation, Centre National de la Recherche Scientifique, Unité Mixte de Recherche 5516, 10 Rue Barrouin, Bât. F, 42000 Saint-Etienne, France. nicolas.sanner@univ-st-etienne.fr
Huot
Nicolas
N
Audouard
Eric
E
Larat
Christian
C
Huignard
Jean-Pierre
JP
Loiseaux
Brigitte
B