| 摘要 |
Provided is a medium authenticity judgment device configured so that a visible light having predetermined color is irradiated, at a predetermined angle of incidence, to a medium comprising an optically variable portion wherein color changes in accordance with a viewing angle; a reflected light having an angle of reflection different from the angle of incidence is received; an evaluation value relating to the optically variable portion is calculated on the basis of the amount of reflected light at the optically variable portion; and the evaluation value is compared to a predetermined threshold value to judge the authenticity of the medium. |
