The detection results showed that the area of the observation area was 3mm², and there were a total of 1327 droplets. The average diameter of these droplets was 9.44μm and the average area was 79.04μm². The diameter distribution of blobs is shown in Figure . It is shown from the above figure that the largest distribution of blob diameters in the detection area was 5.90 μm-6.90 μm, accounting for 18.91% of the quantity. The diameters of most of the blobs ranged from 4.90 μm to 14.90 μm, and the quantity accounted for 84.33%.