Fig. 1. Schematic of laser cleaning online detection system

Fig. 2. Images before and after median filtering. (a) Before filtering; (b) after median filtering (N is set to 3×3)

Fig. 3. Images before and after processing with delighting algorithm. (a) Before processing with delighting algorithm; (b) after processing with delighting algorithm

Fig. 4. Images after segmentation and processing with morphological method. (a) Image after Otus threshold segmentation; (b) image after processing with morphological method; (c) image after delighting

Fig. 5. Effects of edge detection. (a) Edge image; (b) connected domain search image

Fig. 6. Detection results obtained with machine vision method. (a) Unqualified sample surface; (b) detection result obtained with machine vision method(unqualified cleaning); (c) EDS analysis of unqualified sample surface; (d) qualified sample surface; (e) detection result obtained with machine vision method(qualified cleaning); (f) EDS analysis of qualified sample surface