Abstract: An antenna device is provided with a magnetic core having a winding core and first and second flanges provided at one end and the other end of the winding core, respectively, an antenna coil constituted of a wire wound around the winding core, and a metal layer disposed parallel to a coil axis direction of the antenna coil. The metal layer has a slit overlapped with at least a part of the first flange in a plan view.

Abstract: An antenna device is provided with a planar coil antenna having a planar section provided along a first plane and a first folded section provided along a second plane crossing the first plane and a first metal layer. A first border line between the planar section and the first folded section crosses an inner diameter portion of the planar coil antenna. The first metal layer covers at least a part of the planar section of the planar coil antenna and at least a part of the inner diameter portion.

Abstract: Disclosed herein is an antenna device includes a first metal layer having a first slit, an antenna coil having an inner diameter area overlapping with the first slit in planar view and a coil axis perpendicular to the first metal layer, and a first magnetic layer provided on a back surface of the first metal layer, which faces the antenna coil, and provided outside of the antenna coil in planar view. An upper surface of the first magnetic layer facing the back surface of the first metal layer is positioned closer than a far end surface of the antenna coil to the back surface of the first metal layer along the coil axis, as viewed from the back surface of the first metal layer, or is positioned in the same plane as the far end of the antenna coil.

Abstract: Disclosed herein is an antenna device that includes: a metal layer having a first metal plate, a second metal plate that is adjacent to the first metal plate across a slit extending in a first direction, and a connecting part extends over the slit to connect the first metal plate to the second metal plate such that the first and second metal plate are integrated; and an antenna coil having an antenna axis substantially perpendicular to a main surface of the metal layer and defining an inner diameter area surrounded by an innermost line thereof. The inner diameter area of the antenna coil overlaps with the slit in planar view. The slit has a narrower width than the inner diameter area of the antenna coil. The antenna coil has a first exposed part and a second exposed part intersecting with the slit.

Abstract: Disclosed herein is an antenna device that includes an antenna coil having a planar coil pattern, a magnetic sheet that covers one main surface of the antenna coil, and a resin layer provided on the other main surface of the antenna coil and along the coil pattern. The resin layer is substantially the same planar shape as the planar coil pattern.

Abstract: An antenna device is provided with a substrate; an antenna coil formed into a loop-shaped or spiral-shaped on the substrate; a first metallic layer overlapping with a first part of the antenna coil in a planar view; and a second metallic layer overlapping with a second part of the antenna coil different from the first part. The first and second metallic layers are disposed on both sides of a center of an inner diameter portion of the antenna coil in a planar view, respectively. A slit formed between the first and second metallic layers overlaps with the inner diameter portion of the antenna coil in a planar view. At least one of the first and second metallic layers is formed on the substrate together with the antenna coil.

Abstract: A coil component is provided with a substrate; an antenna coil formed into a loop-shaped or spiral-shaped on the substrate; and first and second metallic layers disposed so as to overlap the antenna coil in a planar view and to form a slit sandwiched the first and second metallic layers. The slit overlaps with an inner diameter portion of the antenna coil . At least one of the first and second metallic layers is formed into a loop shape having an opening. The antenna coil overlaps with the opening of at least one of the first and second metallic layers in a planar view.

Abstract: Disclosed herein is antenna device that includes: a first metal member having a first main surface; a second metal member having a second main surface parallel to the first main surface; and an antenna coil having a coil axis perpendicular to the first and second main surfaces, wherein the first metal member constitutes at least a part of a housing of a portable electronic device in which the antenna coil is mounted, at least one slit is formed between the first and second metal members, an inner diameter section of the antenna coil overlaps with the slit in planar view, and the slit has a constant width at least in a region that overlaps with the antenna coil in planar view.