High Average Power Green Laser Based on LED-Side-Pumped Q-Switched Nd:YAG Laser

Abstract

In this paper, we demonstrated a watt-level acousto-optic (A-O) Q-switched intracavity frequency-doubled green laser with high average power and beam quality operation based on an efficient LED-pumped Nd:YAG laser module. For the quasi-continuous wave (QCW) running operation, the average output power of fundamental laser at 1064 nm was as high as 10.3 W at a repetition rate of 100 Hz, corresponding to the highest optical conversion efficiency of 25.4% and a slope efficiency of 31.3%, and the maximum energy of single pulse was up to 100mJ. By optimizing the incidence angle of the KTP crystal to meet the non-critical phase matching condition, greater than 3.8 W of 532 nm average power at a repetition rate of 10 kHz was generated with duration of 192 ns and a beam quality factor of M <sub xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">x</sub> <sup xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">2</sup> = 1.6 and M <sub xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">y</sub> <sup xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">2</sup> = 1.7, corresponding to a frequency doubling conversion efficiency of 45.5%. To the best of our ability, this is the highest average power and high beam quality of an LED-pumped A-O Q-switched intracavity frequency-doubled green laser with watt-level output reported so far.