<p>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 near-infrared rays in different near-infrared wavelength ranges are irradiated onto the paper, thereby discriminating the paper material of the paper by using an absorbance difference (DA) between photometric values. <IMAGE></p>
