Title: LOG-filter-based inspection of cluster Mura and vertical-band Mura on liquid crystal displays
Abstract:In this paper, we suggest to use a 2-D LOG filter to inspect Cluster Mura defects on the FOS images of LCDs, either for round-type Cluster Mura defects or rectangular-type Cluster Mura defects. With t...In this paper, we suggest to use a 2-D LOG filter to inspect Cluster Mura defects on the FOS images of LCDs, either for round-type Cluster Mura defects or rectangular-type Cluster Mura defects. With the 2-D LOG filter, the optimal threshold is analyzed with the SEMU formula. Also, we propose a curvature test approach to detect V-Band Mura defects. In the curvature test approach, a 1-D LOG filter is used to achieve the curve with the smooth curvature tendency. With this estimated curve, V-Band Mura defects could be detected easily. The FOS surface reconstruction verifies this detection approach in a reasonable way. Either for the Cluster Mura detection approach or for the V-Band Mura detection approach, the simulation results demonstrate the LOG filters is very useful in the development of detection algorithms for automatic optical inspection of Mura-like defects.Read More