Next Article in Journal
Implementing Autonomous Driving Behaviors Using a Message Driven Petri Net Framework
Previous Article in Journal
Automatic Hierarchical Classification of Kelps Using Deep Residual Features
Open AccessArticle

A New Stitching Method for Dark-Field Surface Defects Inspection Based on Simplified Target-Tracking and Path Correction

by Xue Chen 1,2,3, Jiaqi Li 1,2,3,* and Yongxin Sui 1,3
1
Changchun Institute of Optics, Fine Mechanics and Physics, Chinese Academy of Sciences, Changchun 130033, China
2
University of Chinese Academy of Sciences, Beijing 100049, China
3
Changchun National Extreme Precision Optics Co., Ltd., Changchun 130033, China
*
Author to whom correspondence should be addressed.
Sensors 2020, 20(2), 448; https://doi.org/10.3390/s20020448
Received: 18 December 2019 / Revised: 7 January 2020 / Accepted: 8 January 2020 / Published: 13 January 2020
(This article belongs to the Section Optical Sensors)
A camera-based dark-field imaging system can effectively detect defects of microns on large optics by scanning and stitching sub-apertures with a small field of view. However, conventional stitching methods encounter problems of mismatches and location deviations, since few defects exist on the tested fine surface. In this paper, a highly efficient stitching method is proposed, based on a simplified target-tracking and adaptive scanning path correction. By increasing the number of sub-apertures and switching to camera perspective, the defects can be regarded as moving targets. A target-tracking procedure is firstly performed to obtain the marked targets. Then, the scanning path is corrected by minimizing the sum of deviations. The final stitching results are updated by re-using the target-tracking method. An experiment was carried out on an inspection of our specially designed testing sample. Subsequently, 118 defects were identified out of 120 truly existing defects, without stitching mismatches. The experiment results show that this method can help to reduce mismatches and location deviations of defects, and it was also effective in increasing the detectability for weak defects. View Full-Text
Keywords: defect inspection; dark-field imaging; image stitching; target tracking; scanning path correction defect inspection; dark-field imaging; image stitching; target tracking; scanning path correction
Show Figures

Figure 1

MDPI and ACS Style

Chen, X.; Li, J.; Sui, Y. A New Stitching Method for Dark-Field Surface Defects Inspection Based on Simplified Target-Tracking and Path Correction. Sensors 2020, 20, 448.

Show more citation formats Show less citations formats
Note that from the first issue of 2016, MDPI journals use article numbers instead of page numbers. See further details here.

Article Access Map by Country/Region

1
Back to TopTop