Patent ID: 7912272

Claim:
A system for automatic discrimination of the authenticity of currency notes, security instruments, security documents and similar documents, said system comprising: a) a suitably located UV visible radiation emitting fluorescent tube light or equivalent source; b) two sets of sensor heads, each sensor head incorporating plurality of photodetectors; c) a signal conditioning hardware and software comprising, a micro-controller to process and normalise sensors data, store or compare online the measured data with the reference data independently for each security document; weight the comparative results to detect the genuineness; d) displays; audio-visual alarm; appropriate slot for insertion of the document under inspection, e) all the above mentioned components/devices/modules being enclosed in box such that the system performance remains immune to the influence of ambient light; and wherein, the said system authenticates a currency notes, security instruments, security documents and similar documents by acquiring transmitted and reflected/fluoresced data, integrated in space and time domain in at least three broad spectral wave bands covering UV visible and optionally NIR part of spectrum, each for transmission and reflection/fluorescence, collected from an area of the document comprising more than half of an entire document surface area, which is kept in a stationary condition during authentication process by illuminating the document using the light from a single broad band source with a provision to use an additional near infra red (NIR) source to provide transmitted and reflected/fluorescence data in NIR region together with transmitted and reflected data in UV visible and near infra red region, and by using the measured transmitted signals in to define a set of ratios and by using the measured reflected/fluoresced signals to define another set of ratios and by comparing these ratios with the corresponding stored reference values to judge authenticity of the document under verification.