| 摘要 |
PROBLEM TO BE SOLVED: To provide a box graphic code card for preventing the use of illegal card by automatically and randum deciding the rotation key of that card based on the bit combination of a basic leading code to be written in an initial code area. SOLUTION: In the box graphic code card 1, there are a main information write area 2 for writing main information such as money amount and an ID information write area 3 for writing personal information or a fingerprint image in the case of use requesting especially high-grade security. Initial money amount data are written in an initial code area 4 at the highest step of the main information write area 2 by a box graphic code rotated and enciphered by a rotation key 'K' original for the card. Thus, the security of the card is improved by a means for enciphering the graphic code through double keys with the bit combination of leading codes as a key for enciphering the graphic code. |
