Fig. 1. Experimental setup schematic of single-pass amplification

Fig. 2. Cross-section of LD module

Fig. 3. Structure of thermal module

Fig. 4. Physical map of LD module

Fig. 5. Variation in thermal focus length with pumping energy

Fig. 6. Output characteristics of oscillator stage of Q-switched laser under different pumping energy. (a) Output energy; (b) pulse width

Fig. 7. Measurement result of beam quality

Fig. 8. Output characteristics of single-pass amplified laser under different pumping energy. (a) Output energy; (b) pulse width

Fig. 9. Amplified beam spot. (a) Beam spot shape; (b) beam spot appearance

Fig. 10. Measurement result of amplified beam quality