Automatic verification system for documents - involves random scan of number of points and comparison of measured values with standard values

摘要

The document verification method is used especially for banknotes, by comparing measured parameters, with ideal values of these parameters at a large number of randomly chosen points. The number of points chosen by greater than a given number to give sufficiently thorough coverage of the document, and a comparator system checks the detected valves against the correct valves for these points. The numbers of measured valves exceeding and falling below these correct values are rotated, and there are means for determining whether these valves fall within acceptable valves. The acceptable valves form a band which covers a mean valve or ideal value. Typical test parameters used may be optical transparency or reflectance.