FIELD: physics.
SUBSTANCE: method involves passing a document past an image signal former such as a line scanning camera with successive illumination of said document using multiple types of radiation. Two or more light sources are used, each forming a unique type of illumination. A look-up table divides the document into separate, consecutive sections, i.e. scanning lines, and determines the type of illumination, e.g. colour, azimuth, reflected or light passing through, for each section of the document during image formation. When the document passes past the image signal former, the light sources are activated in accordance with the sequence defined in the look-up table, which enables to form an image of the document obtained by alternating lines with different types of illumination.
EFFECT: high accuracy of checking banknotes.
12 cl, 10 dwg
