A method for discriminating the genuineness of a certified paper having a printed protuberant portion (M3) having at least an usual ink portion (M32) and an electroluminescent ink portion (M31) that emits an electroluminescent light being exposed to an alternating current electromagnetic field and reflects a light being illuminated by a light having a specified wavelength, comprising the steps of: - detecting a transport of the certified paper in the alternating electromagnetic field by a certified paper detecting means and operating a light detecting means, when a certified paper detecting means detects the certified paper, - exposing at least a portion of the certified paper to a light emitting element emitting the specified wavelength, - detecting a first light emitted from the electroluminescent ink portion (M31) at a light collecting spot with a first light detecting element configured to produce a first output value waveform corresponding to the intensity of electroluminescent light detected from the electroluminescent ink, - detecting a reflected light from the usual ink portion (M32) at a light collecting spot with a second light detecting element configured to produce a second output value waveform corresponding to the intensity of light detected from the usual ink portion (M32) - discriminating the genuineness of the certified paper based on the first and second output value waveform of the first and second detecting elements, - wherein a LED as the light emitting element is turned on, when the detecting means detect the certified paper, and driving an alternating voltage applying means by an alternating voltage control means to produce an alternating-current electromagnetic field only when the second light detecting element detects the reflected light from the usual ink portion (M32). - detecting a transport of the certified paper in the alternating electromagnetic field by a certified paper detecting means and operating a light detecting means, when a certified paper detecting means detects the certified paper, - exposing at least a portion of the certified paper to a light emitting element emitting the specified wavelength, - detecting a first light emitted from the electroluminescent ink portion (M31) at a light collecting spot with a first light detecting element configured to produce a first output value waveform corresponding to the intensity of electroluminescent light detected from the electroluminescent ink, - detecting a reflected light from the usual ink portion (M32) at a light collecting spot with a second light detecting element configured to produce a second output value waveform corresponding to the intensity of light detected from the usual ink portion (M32) - discriminating the genuineness of the certified paper based on the first and second output value waveform of the first and second detecting elements, - wherein a LED as the light emitting element is turned on, when the detecting means detect the certified paper, and driving an alternating voltage applying means by an alternating voltage control means to produce an alternating-current electromagnetic field only when the second light detecting element detects the reflected light from the usual ink portion (M32). <EOS>