Fig. 1. Schematic diagram of the high-repetition-rate, long-pulse, single-frequency seed laser.

Fig. 2. Schematic diagram of the MOPA construction.

Fig. 3. SHG efficiency of (a) an ideal Gaussian laser beam () and (b) a non-perfect Gaussian laser beam ().

Fig. 4. Output laser power and beam quality () of each amplifier.

Fig. 5. Waveform of the output pulse from the main amplifier.

Fig. 6. Linewidth of main amplifier output laser measurement.

Fig. 7. (a) Beam profile and of the single-frequency green laser, and (b) far-field and (c) near-field beam profiles of the fundamental laser.