Highly Stable UV-Mode-Locked Lasers with an Output Power of 35 W at 355 nm

摘要

High power compact UV lasers with diffraction limited beam are required for industrial applications such as laser direct imaging, wafer inspection or photo voltaic. By use of a Nd:GdVO_4 oscillator with a Saturable Bragg Reflector and a single pass amplifier, 73 W output power in mode-locked operation at 80 MHz have been generated with high peak power. By use of two LBO crystals a third harmonic output power of 35 W at 355 nm was demonstrated with an M~2 value of <1.2. This corresponds to 48% nonlinear conversion efficiency.