A powerful diode-pumped laser source for micro-machining with ps pulses in the infrared, the visible and the ultraviolet

We report a ps diode-pumped Nd:YVO4 laser system for micro-machining applications. The system consists of a passively mode-locked oscillator followed by a regenerative amplifier. It provides laser pulses at 1064 nm with a pulse duration of 10.2 ps, a repetition rate of 20 kHz and an average output power of 10.8 W. This average power corresponds to a pulse energy of 0.54 mJ. Second-harmonic generation in LBO and fourth-harmonic generation in BBO provide visible (532-nm) and ultraviolet (266-nm) radiation with pulse energies of 270 mu J and 75 mu J, respectively. Amplification in a diode-pumped single-pass Nd:YVO4 amplifier increases the pulse energy of the fundamental 1064-nm laser pulses to I mJ.