Method and apparatus for paper material discrimination with two near-infrared lights

摘要

A bill discriminating method of discriminating a paper material independent of a light/dense pattern caused by a difference of manufacturing steps and discriminating a paper material of paper without being influenced by humidity or deterioration of the paper material is provided, Two kinds of infrared rays of different kinds of wavelengths are irradiated onto the paper, thereby discriminating the paper material of the paper by using an absorbance difference between photometric values.