METHOD FOR DETERMINING AUTHENTICITY OF ANTI-COUNTERFEIT MEDIUM AND AUTHENTICITY DETERMINING DEVICE FOR ANTI-COUNTERFEIT MEDIUM

摘要

The main purpose of the present invention is to provide a method, etc. for determining the authenticity of an anti-counterfeit medium, with which it is possible to determine, at a high level, the authenticity of the anti-counterfeit medium. The present invention solves the above problem by providing a method for determining the authenticity of an anti-counterfeit medium, the method characterized by: preparing an anti-counterfeit medium having a selectively transmitting layer and a light-emitting layer, the light-emitting layer being stacked on the selectively transmitting layer and containing a phosphor that absorbs an electromagnetic wave having a specific wavelength in the wavelength region from the ultraviolet region to the infrared region and emits another electromagnetic wave having a wavelength different from that of the above electromagnetic wave, wherein the selectively transmitting layer has selective-transmission properties such that the selectively transmitting layer absorbs or reflects the electromagnetic wave and transmits the other electromagnetic wave; disposing the anti-counterfeit medium such that the light-emitting-layer side or the selectively-transmitting-layer side of the anti-counterfeit medium faces an observer; and irradiating the light-emitting-layer side and the selectively-transmitting-layer side of the anti-counterfeit medium with the electromagnetic wave to determine the authenticity of the anti-counterfeit medium by using a change in the form of the other electromagnetic wave as observed by the observer.