High-power pulse-periodic Nd3+-YAG laser with combined pumping by diode arrays

Output characteristics of the pulse-periodic solid-state laser pumped by diode arrays at a pump pulse repetition rate of 8...512 Hz were studied. Three pump types are used: longitudinal raster-lightguide, transverse, and combined ones. Diode arrays with a pulse power of ∼800 W, emitting area sizes of 5 × 25 mm2, and radiation divergence along two mutually perpendicular axes equal to 4° and 15°, respectively, were used as a pump source. The pump current pulse duration was varied within 100–350 µs. Three operating modes were studied: (i) free generation, (ii) passive Q-switch, and (iii) acousto-optic Q-switch ones. The lasing peak pulse power was (i) ∼2 kW(free generation mode), (ii) ∼1.5 MW (passive Q-switch mode), and (iii) ∼100 kW (acousto-optic Q-switch mode). The highest average lasing power was 150 W at a pump pulse repetition rate of 512 Hz. The highest pulsed lasing energy was 0.65 J.