A fast and precise positioning method for circular markers in Mini-LED display panel defect detection

Mini-LED display technology has emerged as a core development direction in next-generation high-end display technology, attributable to its merits of high brightness, high contrast ratio, long operational lifespan, and energy efficiency. Aiming at the task of circular marker localization in the defect detection process of Mini-LED display panels, this paper proposes a circle detection method based on an arc growth strategy. The proposed strategy extracts large arcs from line segments by imposing constraints through the tolerance annulus, thereby reducing the number of least-squares circle fitting processes. Subsequently, the connection of large arcs is implemented by the arc overlap ratio threshold. Finally, candidate circles are flexibly filtered on the basis of the arc angle span. Experimental results demonstrate that compared with advanced methods, this method achieves significantly faster detection speeds, with an average detection time only 46% that of EDCircles. In addition, this method achieves pixel-level location accuracy, excellent noise resistance, robust occlusion tolerance, and intuitive input control parameters.