Efficient intra-cavity second harmonic generation by a diode-pumped actively Q-switched Nd:YAG laser

A compact and efficient intra-cavity doubled, actively Q-switched diode-pumped Nd:YAG laser has been developed. It generates as much as 1.55 W at 532 nm, with pulses of 400 ns at a repetition rate of 15 kHz, with an overall optical-to-optical efficiency of 15.5%. A beam quality factor M2 ≈ 2.35 has been measured at this power level.