IC CARD USED/UNUSED DECISION METHOD, IC CARD, AND IC CARD USE STARTING DEVICE

摘要

PROBLEM TO BE SOLVED: To improve the convenience of the IC card for a user and to eliminate illegal use by a 3rd person by deciding the used/unused state of the IC card through an internal function and allowing the user of the IC card to recognize the state from outside. SOLUTION: The IC card 1 has a conductive circumferential line 11 installed in a peripheral edge part internal layer area and a used/unused decision circuit 13 which is incorporated together with circuit elements such as a communication function actualization part 14 providing various card functions for the IC card 11, an authenticating process part 15, and a storage part 16 and decides the used/unused state of the IC card 1 by detecting variation in electric conduction characteristics of the conductive circumferential line 11 caused when an external force physically damaging the conductive circumferential line 11 is applied from the surface of the IC card 1 to the conductive circumferential line 11.