Fig. 1. Layout of the seed source

Fig. 2. Profile of the pulse of the seed source

Fig. 3. Layout of the experimental setup (L₁, Concave lens; L₂, Convex lens; FI, Faraday-isolator; HWP, Half wave plate; M₁、M₂, 45° reflection mirror; TFP, Thin film polarizer; AM1, Amplifier module Ⅰ; QWP, Quarter-wave plate; M₃; Total reflection mirror; M₄, M₅, 30° reflection mirror; L₃, Concave lens; L₄, Convex lens; AM2, Amplifier module Ⅱ)

Fig. 4. Photo of the laser amplifier

Fig. 5. Relationship between output energy and pump voltage

Fig. 6. Relationship between 532 nm output energy and pump voltage

Fig. 7. The stability of output energy

Fig. 8. Profile of the pulse of the amplifier

Fig. 9. Photo of the light spot: (a) Photo of before optimizing the light spot; (b) Photo of after optimizing the light spot