Patent ID: 7016031

Claim:
A method for detecting and classifying anomalies of a surface of a sample of a material suitable for use as a substrate for storage, display or electronic devices, comprising: supplying radiation to an area of the surface; detecting radiation from the anomalies associated with the area of the surface to provide an output corresponding to the area by means of a detector; and analyzing the detector output for anomalies and classifying the anomalies; wherein the analyzing uses more than one threshold to analyze the detector output and to arrive at at least one classification of the anomalies, said analyzing and classifying comprising processing the output with a first threshold, and classifying the anomalies in a first classification and analyzing the output with a second threshold different from the first threshold, said classifying including applying algorithm(s) to test relationship between anomalies, if any, wherein the output is analyzed with a second threshold without applying the algorithm(s) to test relationship between anomalies.