PRODUCTION METHOD FOR ANTENNA DEVICE

摘要

A method for manufacturing an antenna device is provided, in which frequency deviations caused by various factors of variations of circuit characteristics of an antenna module about to be finished may be controlled so as to be within a possible range of fine finishing adjustments to provide for stabilized communication. The manufacturing method includes a first step S 11 of forming an antenna circuit (11) so that the resonance frequency of the antenna circuit (11) will be lower than an oscillation frequency of the reader/ writer (2). The antenna circuit includes an antenna coil (11a) that receives the magnetic field transmitted from the reader/ writer (2) and a capacitor (11b) electrically connected to the antenna coil (11a). The manufacturing method also includes a second step of affixing a magnetic sheet (12) to the antenna coil (11a) via an adhesive (14). The magnetic sheet is at a face-to-face position with respect to the antenna coil (11a) and is configured to change the inductance of the antenna coil (11a). The adhesive (14) is of a film thickness to change the inductance so that the resonance frequency of the resonance circuit (11) will be coincident with the oscillation frequency depending on the spacing between the antenna coil (11a) and the magnetic sheet (12).