US Patent 6994201 Bill acceptor

A bill acceptor is constructed to include a housing, the housing having a base for holding a banknote for examination, a first light emitter adapted to emit infrared light onto the banknote carried on the base of the housing for examination, a second light emitter adapted to emit ultraviolet light onto the banknote for visual examination, an image sensor adapted to pick up infrared light reflected from the banknote carried on the base of the housing and to convert received light signal into image signal, and a display adapted to display image signal obtained from the image sensor for verifying the authenticity of the banknote.