Fig. 1. Schematic of microscope

Fig. 2. Distribution region of craters(D＜50 μm)

Fig. 3. Count of craters of different diameter (D＜50 μm)

Fig. 4. Count of craters of different diameter (50 μm＜D＜100 μm)

Fig. 5. Count of craters of different diameter (50 μm＜D＜100 μm)

Fig. 6. A typical crater (100 μm＜D＜1000 μm)

Fig. 7. Distribution region of craters(100 μm＜D＜1000 μm)

Fig. 8. Count of craters of different diameter (100 μm＜D＜1000 μm)

Fig. 9. A typical crater (D＞1000 μm)

Fig. 10. Distribution region of craters(D＞1000 μm)

Fig. 11. Count of craters of different diameter (D＞1000 μm)

Fig. 12. Statistical of result(KDP)