Abstract: An antenna device, incorporated in an electronic apparatus, which communicates with an external device via an electromagnetic field signal, comprising: an antenna coil provided by winding a conducting wire in a two-dimensional shape and inductively coupled to the external device; and a thermal diffusion sheet provided so as to overlap the antenna coil at a surface of the antenna coil that faces the external device, wherein the thermal diffusion sheet is provided with a slit formed so as to extend from a region overlapping an opening of the antenna coil to an end of the thermal diffusion sheet and a thermal diffusion sheet side opening or slit connected to the slit and formed in the region overlapping the opening of the antenna coil.

Abstract: An antenna device incorporated in an electronic apparatus to communicate with an external apparatus via an electromagnetic field signal includes a first conductor provided inside a housing of the electronic apparatus and opposing the external apparatus, a loop antenna having an antenna coil conductively coupled to the external apparatus and coiling thereon, a sheet-like second conductor provided as being spaced with a predetermined space from the first conductor and partially overlapping or making contact with a surface of the loop antenna opposite to a surface opposing the external apparatus, and a sheet-like third conductor provided between the first conductor and the second conductor and having one end overlapping or making contact with the first conductor and other end partially overlapping or making contact with the second conductor.

Abstract: An electronic device and an antenna device are provided that use a coil module which is thinned without losing the characteristics of the coil module and which can be mounted in a narrowed space. A coil module including a loop-shaped antenna coil wounded in a planar shape and a sheet-shaped magnetic sheet which is formed of a magnetic material and which overlaps with at least a part of the antenna coil is included. In the coil module, a part of the antenna coil is overlapped with an internal structure of a housing and the magnetic sheet is provided in a position that does not overlap with the internal structure on an antenna coil surface side that overlaps with the internal structure.

Abstract: The purpose of the present invention is to ensure satisfactory antenna communication performance even in a case where an antenna coil is placed on the underside of a thermal diffusion sheet. An antenna device (1), incorporated in an electronic apparatus, which communicates with an external device via an electromagnetic field signal, comprising: an antenna coil (12) provided by winding a conducting wire (12a) in a two-dimensional shape and inductively coupled to the external device; and a thermal diffusion sheet (20) provided so as to overlap the antenna coil at a surface of the antenna coil that faces the external device, wherein the thermal diffusion sheet is provided with a slit (18) formed so as to extend from a region overlapping an opening of the antenna coil to an end of the thermal diffusion sheet and a thermal diffusion sheet side opening (19) or slit connected to the slit and formed in the region overlapping the opening of the antenna coil.

Abstract: An electronic apparatus uses a smaller, thinner antenna module that does not have impairing communication characteristics and can also be mounted in a more narrow space. The electronic apparatus is provided with an antenna module including an antenna coil wound in a planar shape and a magnetic sheet overlapping at least a portion of the antenna coil. The antenna coil is bent, and from the bent portion, a plane that includes one side of the antenna coil on which current flows in one direction is disposed alongside a lateral face of an internal structure of a casing, and a plane that includes another side of the antenna coil on which current flows in the opposite direction than on the one side is disposed to overlap the magnetic sheet. The magnetic sheet is disposed at a position farther from a reader/writer than the other side of the antenna coil is.

Abstract: An antenna device incorporated in an electronic apparatus to communicate with an external apparatus via an electromagnetic field signal includes a first conductor provided inside a housing of the electronic apparatus and opposing the external apparatus, a loop antenna having an antenna coil conductively coupled to the external apparatus and coiling thereon, a sheet-like second conductor provided as being spaced with a predetermined space from the first conductor and partially overlapping or making contact with a surface of the loop antenna opposite to a surface opposing the external apparatus, and a sheet-like third conductor provided between the first conductor and the second conductor and having one end overlapping or making contact with the first conductor and other end partially overlapping or making contact with the second conductor.

Abstract: An electronic apparatus uses a smaller, thinner antenna module that does not have impairing communication characteristics and can also be mounted in a more narrow space. The electronic apparatus is provided with an antenna module including an antenna coil wound in a planar shape and a magnetic sheet overlapping at least a portion of the antenna coil. The antenna coil is bent, and from the bent portion, a plane that includes one side of the antenna coil on which current flows in one direction is disposed alongside a lateral face of an internal structure of a casing, and a plane that includes another side of the antenna coil on which current flows in the opposite direction than on the one side is disposed to overlap the magnetic sheet. The magnetic sheet is disposed at a position farther from a reader/writer than the other side of the antenna coil is.

Abstract: An electronic device and an antenna device are provided that use a coil module which is thinned without losing the characteristics of the coil module and which can be mounted in a narrowed space. A coil module including a loop-shaped antenna coil wounded in a planar shape and a sheet-shaped magnetic sheet which is formed of a magnetic material and which overlaps with at least a part of the antenna coil is included. In the coil module, a part of the antenna coil is overlapped with an internal structure of a housing and the magnetic sheet is provided in a position that does not overlap with the internal structure on an antenna coil surface side that overlaps with the internal structure.