Fig. 1. Device diagram of seed injection electro-optic Q-switched narrow linewidth pulse laser

Fig. 2. Free operation output power with different cavity lengths

Fig. 3. Interference waveform after seed injection

Fig. 4. Pulse waveform before and after injection. (a) Pulse waveform after injection; (b) pulse waveform before injection

Fig. 5. Light pulse waveform after 2 h in afterglow mode

Fig. 6. Beat signal, width after Fourier transform

Fig. 7. (a) Output power changes with pump current before and after injection; (b) diagram of relationship between laser output energy and pump current variation, and divergence angle with pump pulse width variation

Fig. 8. Quality analysis and power stability of output laser beam after injection. (a) Beam quality analysis; (b) power stability