Adaptive Surface Fitting for Inspection of FPD Devices Using Multilevel B-spline Approximation

Abstract

This paper proposes a surface fitting algorithm for inspection of flat panel display(FPD) based on multilevel B-spline approximation(MBA). FPD devices have non-uniform background, and shape and intensity of defects are very various. MBA is useful algorithm for surface fitting but it is sensitive to number of control lattices. As level increases, details of original image can be reconstructed. To detect defect, defective area must not be well-reconstructed. In this paper, we propose a level decision method of MBA for FPD. After process of each level, we decide whether stop to increase level of MBA or not with simple distance measure. Experimental result shows that our proposed method makes to detect defects easy.