To minimize mechanical damage to card constituent elements and to improve productivity by eliminating the need for capacitor capacity adjustment for resonance frequency setting of a resonance circuit of an antenna mechanism in a noncontact IC card.
The card has a flexible inlet of a sheet type resin material inside, resonance units are formed by arraying small plane coils patterned on the entire resin surface of the sheet type resin material and connecting capacitors in electrode structure penetrating the inlet resin between the top and reverse sides by the coils, and a large plane coil is formed surrounding the resonance unit group and connected to a noncontact IC chip; and the resonance frequencies of the respective resonance units are shifted to the frequency of a high-frequency electromagnetic field from a reader writer and frequencies above and below it and combined so that they do not interfere, thereby obtaining wide-band resonance characteristics.
EMORI SUSUMU
IGARASHI SUSUMU
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