| 摘要 |
<p>PURPOSE:To prevent the alteration and fraud use of variable data. CONSTITUTION:When the magnetic card 1 running through a card running passage 9a is irradiated with the light of a transmission type optical sensor 14, the light transmits through the magnetic card 1 to enter a phototransistor 15. When other substance 4, for example, a metal is present in the route of the magnetic card when the light of the transmission type optical sensor 14 transmits through the magnetic card 1, no light transmits through the part where the substance 4 is present and, therefore, an output waveform (a) is outputted from the phototransistor 15. At the same time, a magnetic head 13 reads fixed data such as a shop number, a company code or a name and card inherent data and the output waveform (a) from the phototransistor 15 and the recording value of the waveform of the card inherent data are compared and judged by a comparison and judgment circuit 17 and, when both of them coincide with each other, the magnetic card 1 is judged to be a correct card not forged in material.</p> |
