Latest developments in on- and off-line inspection of bank notes during production
Stephen C. Brown · Proceedings of SPIE, the International Society for Optical Engineering/Proceedings of SPIE · 2004
The inspection of bank notes is a highly labour intensive process where traditionally every note on every sheet is inspected manually. However with the advent of more and more sophisticated security features, both visible and invisible, and the requirement of cost reduction in the printing process, it is clear that automation is required. Machines for the automatic inspection of bank notes have been on the market for the past 10 to 12 years, but recent developments in technology have enabled a new generation of detectors and machines to be developed. This paper focuses on the latest developments in both the off-line and on-line inspection of bank notes covering not only the visible spectrum but also a new range of detectors for inspection some of the more common invisible features used as covert features in today's bank notes.