| 摘要 |
<P>PROBLEM TO BE SOLVED: To provide a reader/writer for IC cards which is capable of detecting whether an IC card exists in a magnetic field or not in a short time. <P>SOLUTION: A reader/writer 1 for IC cards is provided with magnetic field generation means 11 and 12 for generating a magnetic field, communication means 12 and 13 for communicating with an IC card 3 through the magnetic field generated by the magnetic field generation means 11 and 12, and an IC card detection means 15 for detecting whether the IC card 3 exists within the magnetic field generated by the magnetic field generation means 11 and 12 or not. The magnetic field generation means 11 and 12 generate a magnetic field on the basis of a carrier wave, and the IC card detection means 15 detects whether the IC card exists within the magnetic field or not by detecting an amplitude of the carrier wave. <P>COPYRIGHT: (C)2005,JPO&NCIPI |
