COGNITION CARD HAVING MECHANICALLY TESTABLE CONVICTION INFORMATION AND RECORDING MEDIA SUCH AS CREDIT CARD AND METHOD OF TESTING CONVICTION INFORMATION

摘要

A record carrier such as an identification card or a cheque card is fitted with security markings which can be checked mechanically. The card carries a layer with good electric conductivity and a layer of good electric insulation which enclose a layer which is chemically homogeneous. The security features or information can be introduced into the latter by varying the conductivity. This provides safety against falsifications because the irreversible marks cannot be duplicated by a copying process. The markings can be readily checked for attempts of falsifications.