Influence of Pump Pulse Duration on the Output Performance of a LED-Pumped Nd:YAG Laser

In this paper, we performed an experimental study of a LED-pumped Nd:YAG laser that works in QCW and Q-switch modes. We examined how the pump pulse duration affects the laser output. The laser rod was a Nd:YAG crystal with a diameter of 7 mm and a length of 95 mm, side-pumped by 30 LED arrays, each with 18 single dies at 810 nm. The maximum output energy at 1064 nm was 10.5 mJ in the QCW mode, with a pump energy of 81 mJ (230 µs pulses at 1 Hz). The optical conversion efficiency and the slope efficiency were 12.5% and 18%, respectively. In the PQS mode, the output energy was 250 µJ, with a pulse width of 190 ns (FWHM), corresponding to a peak power of 1.31 kW. The beam divergence was 0.3 mrad with TEM00 mode. This LED-pumped Q-switched Nd:YAG laser can be used for laser range finder applications.