| 摘要 |
<P>PROBLEM TO BE SOLVED: To provide a radio tag that, even if a number of unnecessary radio tags continue to exist, will not cause electromagnetic wave interference to the other contiguous radio tags nor place a large load on an external device, while eliminating the fear of personal information or information related to secret information being illegally read by third parties, the radio tag being usable only for a certain period of time, as during an event. <P>SOLUTION: The radio tag of the passive type receives electric power and signals from electromagnetic waves supplied from the external device and sends response signals to the electric power and signals received. Upon receiving a particular signal from the external device, the radio tag varies its circuit configuration in an irreversible manner. <P>COPYRIGHT: (C)2006,JPO&NCIPI |
