Fig. 1. Laser rod cross-section pumped-light two-dimensional and three-dimensional distribution map.

Fig. 2. Output energy of multi-pass amplification.

Fig. 3. Amplifier stored energy and energy extraction efficiency after multi-pass amplification.

Fig. 4. (a) Time pulse waveform after multi-pass amplification and (b) the value of the square pulse distortion for each pass.

Fig. 5. Nd:glass square rod amplifier structure.

Fig. 6. Fluorescence distribution of Nd:glass amplifier.

Fig. 7. Influence of pump power on Nd:glass amplifier gain.

Fig. 8. Four-pass amplification light path diagram. AMP: amplifier; FR: Faraday rotator; L: len; M: mirror; P: polarizer; PC: pockels cell; SF: spatial filter.

Fig. 9. Energy stability of the Nd:glass amplifier.

Fig. 10. Spectrum diagram (a) seed and (b) after amplification.

Fig. 11. Time waveform diagram.