| 摘要 |
PROBLEM TO BE SOLVED: To easily provide matching by reducing floating capacity between an antenna coil and a plane conductive layer for forming a slit above the antenna coil.SOLUTION: An antenna device 1 includes: a substrate 10; a loop-shaped or spiral antenna coil 11 formed on the substrate 10; and first and second metal layers 12A, 12B formed on positions overlapped to the antenna coil 11 in plan view. A slit SL composed of an area held between the first metal layer 12A and the second metal layer 12B is overlapped to an inner-diameter part of the antenna coil 11. A plane shape of at least one of the first and second metal layers 12A, 12B is a loop shape and the antenna coil 11 is overlapped to an aperture of the loop shape of at least one of the first and second metal layers 12A, 12B in plan view. |
