Apparatus for identifying sheet-like printed matters

Abstract

An apparatus for identifying whether a sheet-like printed matter is true or false comprises means for detecting a plurality of positions of a moving sheet-like printed matter to produce a plurality of position signals, timing signal generating means for producing timing signals on the basis of the position signals, a reference light source for irradiating an information detecting area lying on the object moving path to detect the information of the sheet-like object, opto-electric converting means which produces an electric signal with an amplitude corresponding to an intensity of a reference light transmitted through or reflected from the printed matter when the object exists in the information detecting area and an electric signal with an amplitude corresponding to an intensity of reference light when the object does not exist in the information detecting area; integration means for integrating the electrical signal from the opto-electric converting means which integrates an electric signal from the opto-electric converting means during a first period defined by a timing signal from the timing signal generating means and integrates an electric output signal of the printed matter during the second period defined by the timing signal from the timing signal generating means, an operation means for operating a ratio of the integrated data of the reference light with integrated data of the printed data of the printed matter, and judging means which compares the operated data derived from the operation means with the data representing a true printed matter previously stored to judge whether the printed matter is true or not.