Variable pulse duration laser for material processing

Abstract

We have developed a means to electronically tune laser pulse durations and achieve nearly constant, stable output power. This technique may be used to obtain variable pulse durations and peak pow-ers at a constant pulse repetition rate, or constant pulse durations over a range of pulse repetition rates. These new capabilities allow great flexibility for material processing applications, making it possible to tailor and optimize the performance of a single laser for a wide variety of applications. We report development of next-generation Q-switched, intra-cavity frequency-converted, diode-pumped, near diffraction-limited Nd:YAG lasers with output powers of 30 W at 355 nm and 40 W at 532 nm. Operating at 532 nm we have demonstrated a variable pulse width externally adjustable over the range of 40 ns to 300 ns at constant pulse repetition rates.