摘要 |
Forged bank notes are no longer reliably distinguishable from bank note originals (BN) on the basis of their luminescent fibers. According to the invention, the excitation of the fibers to luminescence is effected by means of excitation radiation (S) from the restricted wavelength range from 600 to 640 nm or from 520 to 550 nm, since the forgeries do not luminescence in this range but the originals luminescence red. Detection is therefore effected in the wavelength range from 640 to 700 nm.
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