Fig. 1. Illustration of defocusing distance and incident angle

Fig. 2. Scanning results of laser pulses under different advance lengths. (a) 8 μm; (b) 4 μm

Fig. 3. Simulation results of laser polished surface

Fig. 4. Laser spot effective lap rate model

Fig. 5. Influence of defocusing distance on polishing results.(a) Influence of defocusing distance on linewidth of single line of polishing； (b) influence of defocusing distance on PV value of polished bottom

Fig. 6. Influence of incident angle on polishing results. (a) Influence of incident angle on linewidth of single line of polishing；(b) influence of incident angle on PV value of polished bottom