| 摘要 |
In order to improve the communication performance of NFC by improving the communication characteristic of an antenna coil even if the antenna coil has a long and narrow shape, an antenna device (1), which is incorporated into an electronic apparatus (30) and communicates with an external apparatus via an electromagnetic field signal, is provided with: an antenna coil (12) which is provided by winding a conducting wire (12a) such that the conducting wires facing each other in a width direction with an opening (12b) therebetween are close to each other, and is inductively coupled to an external apparatus; and a magnetic sheet (20) which is formed from a magnetic material and provided on the reverse side to a surface facing the external apparatus of the antenna coil so as to overlap with part of the antenna coil. The antenna coil is divided into two parts, one side part (12a1) in which the conducting wire is wound in one direction and the other side part (12a2) in which the conducting wire is wound in the other direction, with a straight line (L1) running through the opening in the longitudinal direction of the antenna coil therebetween, and is configured such that the one side part overlaps with the magnetic sheet, and a difference is provided between the magnetic property of the one side part and the magnetic property of the other side part. |
