Antenna device and IC card equipped with the same

Abstract

To make more of the magnetic flux substantially parallel to the axial direction to interlink with a coil conductor in an antenna device having two magnetic bodies arranged so as to sandwich the coil conductor in the axial direction.SOLUTION: An antenna device 1 includes a coil pattern 110 and magnetic bodies 20 and 40 arranged to sandwich the coil pattern 110 in the axial direction. The magnetic body 40 has a first region 41 overlapping the opening region 110a of the coil pattern 110, a second region 42 protruding from the first region 41 in the Y direction so as to overlap with a first section 111 of the coil pattern 110, and a third region 43 protruding from the first region 41 in the X direction so as to overlap with a third section 113 of the coil pattern 110, and also has a first cutout region 71 provided at a position overlapping with the second section 112 of the coil pattern 110 so as not to overlap with the second section 112. The magnetic body 20 has a fourth region 24 overlapping with the opening region 110a of the coil pattern 110 when viewed in the axial direction.SELECTED DRAWING: Figure 5

Description

[Technical Field]

[0001] The present disclosure relates to an antenna device and an IC card including the same. [Background technology]

[0002] Patent Document 1 discloses an antenna coil for a tag having a structure in which a coil body is sandwiched between two magnetic core members in the axial direction so that magnetic flux substantially parallel to the axial direction can easily interlink with the coil body. [Prior art documents] [Patent documents]

[0003] [Patent Document 1] Japanese Patent Application Laid-Open No. 2002-324221 Summary of the Invention [Problem to be solved by the invention]

[0004] However, the tag antenna coil described in Patent Document 1 has a problem in that many magnetic flux components bypass the magnetic core member without interlinking with the coil body.

[0005] The present disclosure describes a technology for an antenna device having a coil conductor and two magnetic bodies arranged to sandwich the coil conductor in the axial direction, which suppresses magnetic flux components that bypass the magnetic core body without interlinking with the coil conductor, while allowing more magnetic flux to interlink with the coil conductor. [Means for solving the problem]

[0006] An antenna device according to one aspect of the present disclosure comprises a coil conductor, a first magnetic body arranged on one side of the coil conductor in the axial direction, and a second magnetic body arranged on the other side of the coil conductor in the axial direction, wherein the first magnetic body has a first region overlapping with an opening region of the coil conductor when viewed from the axial direction, a second region protruding from the first region to one side in the first direction and overlapping with the coil conductor, and a third region protruding from the first region to one side in a second direction perpendicular to the first direction and overlapping with the coil conductor, the second magnetic body has a fourth region overlapping with the opening region of the coil conductor when viewed from the axial direction, a fifth region protruding from the fourth region to the other side in the first direction and overlapping with the coil conductor, and a sixth region protruding from the fourth region to the other side in the second direction and overlapping with the coil conductor, and the first magnetic body has a first cutout region whose outer edge is located inside a first intersection between a first virtual line extending an outer peripheral edge of the second region in the second direction and a second virtual line extending an outer peripheral edge of the third region in the first direction. [Effects of the Invention]

[0007] According to the present disclosure, in an antenna device having a coil conductor and two magnetic bodies arranged to sandwich the coil conductor in the axial direction, a technology is provided that allows more magnetic flux to link to the coil conductor while suppressing magnetic flux components that bypass the magnetic core body without linking to the coil conductor. [Brief explanation of the drawings]

[0008] [Figure 1] FIG. 1 is a schematic perspective view showing the appearance of an IC card 2 equipped with an antenna device according to an embodiment of the present disclosure. [Figure 2] FIG. 2 is a schematic exploded perspective view for explaining the structure of the IC card 2. As shown in FIG. [Figure 3] FIG. 3 is a YZ cross-sectional view of the IC card 2. [Figure 4] FIG. 4 is an XZ cross-sectional view of the IC card 2. [Figure 5] FIG. 5 is a schematic plan view for explaining the configuration of the antenna device 1. As shown in FIG. [Figure 6] FIG. 6 is a schematic plan view for explaining the shapes of the magnetic bodies 20 and 40. As shown in FIG. [Figure 7] FIG. 7 is a schematic perspective view of the IC module 60 as seen from the rear side. [Figure 8] FIG. 8 is a schematic diagram showing a state in which the IC card 2 and the card reader 6 communicate with each other. [Figure 9] FIG. 9 is a YZ cross-sectional view of an IC card 3 according to a first modified example. [Figure 10] FIG. 10 is a schematic plan view for explaining the configuration of an antenna device 1 that can be used in an IC card 3 according to a first modified example. [Figure 11] FIG. 11 is a schematic plan view for explaining the shapes of the magnetic bodies 20 and 40 used in the IC card 3 according to the first modified example. [Figure 12] FIG. 12 is a schematic plan view for explaining the shapes of the magnetic bodies 20 and 40 according to the second modified example. [Figure 13] FIG. 13 is a schematic plan view for explaining the shapes of the magnetic bodies 20 and 40 according to the third modified example. [Figure 14] FIG. 14 is a schematic plan view for explaining the shapes of the magnetic bodies 20 and 40 according to the fourth modified example. [Figure 15] FIG. 15 is a schematic plan view for explaining the shapes of the magnetic bodies 20 and 40 according to the fifth modified example. [Figure 16] FIG. 16 is a schematic plan view for explaining the shapes of the magnetic bodies 20 and 40 according to the sixth modified example. [Figure 17] FIG. 17 is a schematic plan view for explaining the shapes of the magnetic bodies 20 and 40 according to the seventh modified example. [Figure 18] FIG. 18 is a YZ cross-sectional view of an IC card 4 according to an eighth modified example. DETAILED DESCRIPTION OF THE INVENTION

[0009] Hereinafter, embodiments of the technology according to the present disclosure will be described in detail with reference to the accompanying drawings.

[0010] FIG. 1 is a schematic perspective view showing the appearance of an IC card 2 equipped with an antenna device according to an embodiment of the present disclosure.

[0011] 1, the IC card 2 according to this embodiment is a plate-like body with the Y direction as the longitudinal direction, the X direction as the lateral direction, and the Z direction as the thickness direction, and has an upper surface 2a and a back surface 2b that form the XY plane. The IC card 2 has an IC module (described later) built in, and terminal electrodes E of the IC module are exposed on the upper surface 2a of the IC card 2.

[0012] Fig. 2 is a schematic exploded perspective view for explaining the structure of an IC card 2 including the antenna device 1 according to this embodiment, Fig. 3 is a YZ cross-sectional view of the IC card 2, and Fig. 4 is an XZ cross-sectional view of the IC card 2.

[0013] The IC card 2 shown in FIGS. 2 to 4 has a structure in which a metal plate 10, an antenna device 1, and a metal plate 50 are layered in this order from the back surface 2b side to the top surface 2a side. The metal plate 10 is a first card substrate made of a metal such as stainless steel or titanium, and its surface forms the back surface 2b of the IC card 2. The metal plate 50 is a second card substrate made of a metal such as stainless steel or titanium, and its surface forms the top surface 2a of the IC card 2. In this way, the IC card 2 is a card in which a metal plate is used for the main body.

[0014] The antenna device 1 according to this embodiment is composed of magnetic bodies 20 and 40 and a coil conductor 100 sandwiched between the magnetic bodies 20 and 40 in the Z direction. The coil conductor 100 includes coil patterns 110 and 120 and is formed on a surface 31 of a substrate 30 made of a PET film, a polyimide film, or the like. The axial direction of the coil patterns 110 and 120 is the Z direction, so that the magnetic body 40 is disposed on one side in the axial direction (the +Z direction side) of the coil conductor 100, and the magnetic body 20 is disposed on the other side in the axial direction (the -Z direction side) of the coil conductor 100. The substrate 30 and the magnetic body 20 are bonded via an adhesive layer 81. The substrate 30 and the magnetic body 40 are bonded via an adhesive layer 82. Examples of materials for the adhesive layers 81 and 82 include double-sided acrylic tape, thermosetting resin, and thermoplastic resin.

[0015] The magnetic body 40 and the metal plate 50 are provided with through holes 48 and 51, respectively. These through holes 48 and 51 overlap in the Z direction, which is the stacking direction. An IC module 60 is disposed inside the through hole 51 of the metal plate 50.

[0016] The IC module 60 includes a module substrate 61, an IC chip 62 mounted on or built into the module substrate 61, and a coupling coil 63. The IC chip 62 is protected by being covered with a dome-shaped protective resin 64. A terminal electrode E shown in FIG. 1 is provided on the surface of the module substrate 61 opposite to the surface on which the IC chip 62 is mounted. The IC module 60 having such a configuration is electromagnetically coupled to a coil pattern 120 that is a part of the coil conductor 100. This enables communication between an external card reader and the IC chip 62 via a coil pattern 110 that is another part of the coil conductor 100. In other words, the coil pattern 110 is an antenna coil, and the coil pattern 120 is a coupling coil.

[0017] Fig. 5 is a schematic plan view for explaining the configuration of the antenna device 1 according to this embodiment. Note that line AA in Fig. 5 indicates the cross-sectional position of Fig. 3, and line BB in Fig. 5 indicates the cross-sectional position of Fig. 4.

[0018] 5, the coil conductor 100 included in the antenna device 1 according to this embodiment includes a coil pattern 110 that makes multiple turns around the outer edge of the substrate 30, and a coil pattern 120 that is connected to each turn of the coil pattern 110 and makes multiple turns around so as to overlap with the through-holes 48 of the magnetic body 40. The coil patterns 110 and 120 are located on the same plane. The coil pattern 120 overlaps in the Z direction with the IC module 60 that is placed in the through-hole 51 of the metal plate 50, via the through-hole 48 of the magnetic body 40.

[0019] 5, the coil pattern 110 and the coil pattern 120 each have approximately four turns. The coil pattern 120 is a portion that winds around the coil conductor 100 and protrudes toward the opening region 110a of the coil pattern 110. In other words, each turn of the coil conductor 100 is made up of a coil pattern 110 having less than one turn and a coil pattern 120 having less than one turn.

[0020] The coil pattern 110 functions as an antenna coil that couples with an external card reader during actual use. The coil pattern 120 functions as a coupling coil that couples with the IC module 60. The coil pattern 120 may function as part of an antenna coil that couples with an external card reader. Furthermore, when the outer peripheral end 101 of the coil conductor 100 is the starting point and the inner peripheral end 102 of the coil conductor 100 is the end point, the coil pattern 110 winds around in a right-handed (clockwise) direction and the coil pattern 120 winds around in a left-handed (counterclockwise) direction when viewed from the direction shown in FIG. 5. In other words, the winding directions of the coil pattern 110 and the coil pattern 120 are opposite to each other.

[0021] The coil pattern 110 has a first section 111 and a fifth section 115 which include portions extending in the first direction, that is, the X direction, a third section 113 and a seventh section 117 which include portions extending in the second direction, that is, the Y direction, and a second section 112, a fourth section 114, a sixth section 116, and an eighth section 118 which include portions bending from the X direction to the Y direction or from the Y direction to the X direction.

[0022] One end of the first section 111 is connected to one end of the second section 112. The other end of the second section 112 is connected to one end of the third section 113. The other end of the third section 113 is connected to one end of the fourth section 114. The other end of the fourth section 114 is connected to one end of the fifth section 115. The other end of the fifth section 115 is connected to one end of the sixth section 116. The other end of the sixth section 116 is connected to one end of the seventh section 117. The other end of the seventh section 117 is connected to one end of the eighth section 118. The other end of the eighth section 118 is connected to the other end of the first section 111. Each turn that constitutes the coil pattern 120 is connected to the first section 111 of the coil pattern 110.

[0023] As shown in FIG. 5, the magnetic bodies 20 and 40 both overlap with a part of the coil pattern 110 and a part of the opening region 110a in a plan view seen from the Z direction.

[0024] The magnetic body 40, which is the first magnetic body, has, when viewed from the Z direction, which is the axial direction, a first region 41 overlapping the opening region 110a of the coil pattern 110, a second region 42 protruding from the first region 41 in the +Y direction (one side in the Y direction) to overlap with the first section 111 of the coil pattern 110 and overlapping with the first section 111, and a third region 43 protruding from the first region 41 in the +X direction (one side in the X direction) to overlap with the third section 113 of the coil pattern 110. The through hole 48 of the magnetic body 40 is provided in the first region 41. The second region 42 of the magnetic body 40 may include a portion extending beyond the first section 111 of the coil pattern 110 to an outer region of the coil pattern 110. The third region 43 of the magnetic body 40 may include a portion that extends beyond the third section 113 of the coil pattern 110 to an outer region of the coil pattern 110. Furthermore, the magnetic body 40 partially overlaps with the fourth section 114, the fifth section 115, the sixth section 116, the seventh section 117, and the eighth section 118 of the coil pattern 110, but does not include a portion that extends beyond the fourth section 114, the fifth section 115, the sixth section 116, the seventh section 117, and the eighth section 118 of the coil pattern 110 to an outer region of the coil pattern 110. Furthermore, the magnetic body 40 does not overlap with the second section 112 of the coil pattern 110.

[0025] The magnetic body 20, which is the second magnetic body, has, when viewed from the Z direction, which is the axial direction, a fourth region 24 overlapping with the opening region 110a of the coil pattern 110, a fifth region 25 protruding from the fourth region 24 in the −Y direction (the other side in the Y direction) to overlap with the fifth section 115 of the coil pattern 110 and overlapping with the fifth section 115, and a sixth region 26 protruding from the fourth region 24 in the −X direction (the other side in the X direction) to overlap with the seventh section 117 of the coil pattern 110. The fourth region 24 of the magnetic body 20 has a portion overlapping with the coil pattern 120 when viewed from the Z direction. The fifth region 25 of the magnetic body 20 may include a portion extending beyond the fifth section 115 of the coil pattern 110 to an outer region of the coil pattern 110. The sixth region 26 of the magnetic body 20 may include a portion that extends beyond the seventh section 117 of the coil pattern 110 to an outer region of the coil pattern 110. Furthermore, the magnetic body 20 partially overlaps with the first section 111, the second section 112, the third section 113, the fourth section 114, and the eighth section 118 of the coil pattern 110, but does not include a portion that extends beyond the first section 111, the second section 112, the third section 113, the fourth section 114, and the eighth section 118 of the coil pattern 110 to an outer region of the coil pattern 110. Furthermore, the magnetic body 20 does not overlap with the sixth section 116 of the coil pattern 110.

[0026] Moreover, the first region 41 of the magnetic body 40 and the fourth region 24 of the magnetic body 20 overlap each other when viewed from the Z direction, which is the axial direction.

[0027] FIG. 6 is a schematic plan view for explaining the shapes of the magnetic bodies 20 and 40. As shown in FIG.

[0028] 6, the magnetic body 40 has an outer peripheral edge E1 that extends in the X direction and forms the end of the second region 42 in the +Y direction, and an outer peripheral edge E2 that extends in the Y direction and forms the end of the third region 43 in the +X direction. If we imagine a first imaginary line L1 extending from the outer peripheral edge E1 in the +X direction and a second imaginary line L2 extending from the outer peripheral edge E2 in the +Y direction, the magnetic body 40 has a first cutout region 47 in a portion adjacent to the first imaginary line L1 and the second imaginary line L2. In other words, edges 47a and 47b that define the first cutout region 47 are located inside an intersection P1 between the first imaginary line L1 and the second imaginary line L2.

[0029] As described above, the second region 42 of the magnetic body 40 may include a portion that extends beyond the first section 111 of the coil pattern 110 and into the outer region of the coil pattern 110. In this case, the outer peripheral edge E1 of the magnetic body 40 is located in the outer region of the coil pattern 110. Similarly, the third region 43 of the magnetic body 40 may include a portion that extends beyond the third section 113 of the coil pattern 110 and into the outer region of the coil pattern 110. In this case, the outer peripheral edge E2 of the magnetic body 40 is located in the outer region of the coil pattern 110.

[0030] In contrast, the outer peripheral edge E5 of the magnetic body 40, which extends in the X direction and is located opposite the outer peripheral edge E1, may overlap with the fifth section 115 of the coil pattern 110, but may not include a portion extending beyond the fifth section 115 of the coil pattern 110 to the outer region of the coil pattern 110. In this case, the outer peripheral edge E5 of the magnetic body 40 is located inside the outer region of the coil pattern 110. Similarly, the outer peripheral edge E6 of the magnetic body 40, which extends in the Y direction and is located opposite the outer peripheral edge E2, may overlap with the seventh section 117 of the coil pattern 110, but may not include a portion extending beyond the seventh section 117 of the coil pattern 110 to the outer region of the coil pattern 110. In this case, the outer peripheral edge E6 of the magnetic body 40 is located inside the outer region of the coil pattern 110.

[0031] 6, magnetic body 20 has an outer peripheral edge E3 that extends in the X direction and forms the end of fifth region 25 in the -Y direction, and an outer peripheral edge E4 that extends in the Y direction and forms the end of sixth region 26 in the -X direction. If we imagine a third imaginary line L3 extending from outer peripheral edge E3 in the -X direction and a fourth imaginary line L4 extending from outer peripheral edge E4 in the -Y direction, magnetic body 20 has a second cutout region 27 in a portion adjacent to third imaginary line L3 and fourth imaginary line L4. In other words, edges 27a and 27b that define second cutout region 27 are located inside intersection P2 of third imaginary line L3 and fourth imaginary line L4.

[0032] As described above, the fifth region 25 of the magnetic body 20 may include a portion that extends beyond the fifth section 115 of the coil pattern 110 and into the outer region of the coil pattern 110. In this case, the outer peripheral edge E3 of the magnetic body 20 is located in the outer region of the coil pattern 110. Similarly, the sixth region 26 of the magnetic body 20 may include a portion that extends beyond the seventh section 117 of the coil pattern 110 and into the outer region of the coil pattern 110. In this case, the outer peripheral edge E4 of the magnetic body 20 is located in the outer region of the coil pattern 110.

[0033] In contrast, the outer peripheral edge E7 of the magnetic body 20, which extends in the X direction and is located opposite the outer peripheral edge E3, may overlap with the first section 111 of the coil pattern 110, but may not include a portion extending beyond the first section 111 of the coil pattern 110 to the outer region of the coil pattern 110. In this case, the outer peripheral edge E7 of the magnetic body 20 is located inside the outer region of the coil pattern 110. Similarly, the outer peripheral edge E8 of the magnetic body 20, which extends in the Y direction and is located opposite the outer peripheral edge E4, may overlap with the third section 113 of the coil pattern 110, but may not include a portion extending beyond the third section 113 of the coil pattern 110 to the outer region of the coil pattern 110. In this case, the outer peripheral edge E8 of the magnetic body 20 is located inside the outer region of the coil pattern 110.

[0034] 3, when a magnetic flux φ1 in the Y direction is applied to the antenna device 1 according to this embodiment, the magnetic flux flows, for example, through the second region 42 of the magnetic body 40, the first region 41 of the magnetic body 40, the fourth region 24 of the magnetic body 20, and the fifth region 25 of the magnetic body 20, and interlinks with the coil pattern 110. Also, when a magnetic flux φ2 in the X direction is applied to the antenna device 1 according to this embodiment, the magnetic flux flows, for example, through the third region 43 of the magnetic body 40, the first region 41 of the magnetic body 40, the fourth region 24 of the magnetic body 20, and the sixth region 26 of the magnetic body 20, and interlinks with the coil pattern 110. Therefore, even though the antenna device 1 according to this embodiment is sandwiched between the metal plates 10 and 50 in the Z direction, which is the axial direction, it is possible to cause magnetic flux in the XY plane direction to interlink with the coil pattern 110.

[0035] On the other hand, part of the magnetic flux in the XY plane direction passes through the second region 42 of the magnetic body 40, the first region 41 of the magnetic body 40, and the third region 43 of the magnetic body 40 without interlinking with the coil pattern 110. Another part of the magnetic flux in the XY plane direction passes through the fifth region 25 of the magnetic body 20, the fourth region 24 of the magnetic body 20, and the sixth region 26 of the magnetic body 20 without interlinking with the coil pattern 110. Since such magnetic flux components do not interlink with the coil pattern 110, they do not contribute to communication. However, in this embodiment, the first cutout region 47 is provided in the magnetic body 40 and the second cutout region 27 is provided in the magnetic body 20, so that the magnetic flux components that do not interlink with the coil pattern 110 are reduced.

[0036] The first cutout region 47 of the magnetic body 40 is located at a position that overlaps with the second section 112 of the coil pattern 110, so that the magnetic body 40 does not overlap with the second section 112 of the coil pattern 110. The first cutout region 47 of the magnetic body 40 is located on the +X-direction side of the second region 42 of the magnetic body 40 and on the +Y-direction side of the third region 43 of the magnetic body 40. Edges 47a and 47b that define the first cutout region 47 extend in the X and Y directions, respectively. Therefore, the angle formed by the edge 47a and the edge 47b is approximately 90°.

[0037] Because the magnetic body 40 has such a first cutout region 47, the magnetic flux components that bypass from the second region 42 to the third region 43 of the magnetic body 40 without interlinking with the coil pattern 110, or from the third region 43 to the second region 42 of the magnetic body 40 without interlinking with the coil pattern 110, are reduced, and more magnetic flux interlinks with the coil pattern 110 and flows to the magnetic body 40. The first cutout region 47 of the magnetic body 40 may overlap with the opening region 110a of the coil pattern 110. This makes it possible to further reduce the magnetic flux components that bypass the magnetic body 40 without interlinking with the coil pattern 110.

[0038] The second cutout region 27 of the magnetic body 20 is located at a position that overlaps with the sixth section 116 of the coil pattern 110, so that the magnetic body 20 does not overlap with the sixth section 116 of the coil pattern 110. The second cutout region 27 of the magnetic body 20 is located on the -X direction side of the fifth region 25 of the magnetic body 20 and on the -Y direction side of the sixth region 26 of the magnetic body 20. Edges 27a and 27b that define the second cutout region 27 extend in the X direction and the Y direction, respectively. Therefore, the angle formed by the edge 27a and the edge 27b is approximately 90°.

[0039] Because the magnetic body 20 has such a second cutout region 27, the magnetic flux components that bypass from the fifth region 25 to the sixth region 26 of the magnetic body 20 without interlinking with the coil pattern 110, or from the sixth region 26 to the fifth region 25 of the magnetic body 20 without interlinking with the coil pattern 110, are reduced, and more magnetic flux interlinks with the coil pattern 110 and flows to the magnetic body 40. The second cutout region 27 of the magnetic body 20 may overlap with the opening region 110a of the coil pattern 110. This makes it possible to further reduce the magnetic flux components that bypass the magnetic body 20 without interlinking with the coil pattern 110.

[0040] In the example shown in FIG. 6 , the outer shape of the magnetic body 20 and the outer shape of the magnetic body 40 are the same. This allows the magnetic body 20 and the magnetic body 40 to be manufactured using the same process. For example, if the magnetic bodies 20 and 40 are made of magnetic sheets, the cutting process of the magnetic body 20 and the cutting process of the magnetic body 40 can be performed simultaneously. Then, by forming a through hole 48 in one of the magnetic sheets, the magnetic body 40 is completed. However, it is not essential that the outer shape of the magnetic body 20 and the outer shape of the magnetic body 40 are the same, and they may have different outer shapes. For example, the magnetic body 20 does not have to have the second cutout region 27.

[0041] As shown in FIGS. 2 to 4 , a first spacer 71 may be arranged in the same plane as the magnetic body 40, and a second spacer 72 may be arranged in the same plane as the magnetic body 20. The first spacer 71 and the second spacer 72 are non-magnetic insulating members made of resin or the like. The first spacer 71 is a member that is in the same plane as the magnetic body 40 and fills the space where the magnetic body 40 does not exist, and a part of it overlaps with the magnetic body 20. The second spacer 72 is a member that is in the same plane as the magnetic body 20 and fills the space where the magnetic body 20 does not exist, and a part of it overlaps with the magnetic body 40. By providing such a first spacer 71 and a second spacer 72, it is possible to improve the flatness of both surfaces of the antenna device 1 according to this embodiment.

[0042] FIG. 7 is a schematic perspective view of the IC module 60 as seen from the rear side.

[0043] As shown in FIG. 7, the IC module 60 includes a module substrate 61, an IC chip 62 mounted on or built into the module substrate 61, and a coupling coil 63. The IC chip 62 is protected by being covered with a dome-shaped protective resin 64. The protective resin 64 is made of an insulating material. The terminal electrode E shown in FIG. 1 is provided on the front surface of the module substrate 61. The IC module 60 having such a configuration is housed in a through hole 51 formed in a metal plate 50. When the IC module 60 is housed in the through hole 51, the coupling coil 63 and the coil pattern 120 are electromagnetically coupled. The coil pattern 120 is connected to the coil pattern 110, which functions as an antenna coil, and the IC module 60 can communicate with the outside via the coil pattern 110.

[0044] 8, when the IC card 2 is brought close to the card reader 6, communication can be performed between the card reader 6 and the IC chip 62 by the magnetic flux components in the XY plane direction emitted by the card reader 6. In other words, the card reader 6 is coupled to the coupling coil 63 of the IC module 60 via the coil conductor 100, thereby realizing communication with the IC chip 62.

[0045] As described above, the IC card 2 according to this embodiment has a structure in which both sides are made up of metal plates 10, 50 and the antenna device 1 is sandwiched between these metal plates 10, 50. However, since the first cutout region 47 is provided in the magnetic body 40 and the second cutout region 27 is provided in the magnetic body 20, it is possible to effectively link magnetic flux components in the XY plane direction to the coil pattern 110. In order to further increase the magnetic flux linking with the coil pattern 110, the thickness of the magnetic bodies 20, 40 may be made greater than the thickness of the coil conductor 100.

[0046] Furthermore, since the magnetic body 20 is interposed between the coil pattern 120 and the metal plate 10, the generation of eddy currents caused by the magnetic flux generated by the coil pattern 120 being applied to the metal plate 10 is also suppressed.

[0047] FIG. 9 is a YZ cross-sectional view of an IC card 3 according to a first modified example.

[0048] As shown in FIG. 9, the IC card 3 according to the first modification differs from the IC card 2 shown in FIGS. 1 to 4 in that the metal plate 50 does not have a through-hole 51 and a contact-type IC module 90 is used instead of the IC module 60. The IC module 90 is disposed inside the through-hole 48 of the magnetic body 40. The IC module 90 includes a module substrate 91, an IC chip 92 mounted on or built into the module substrate 91, and connection terminals 93 and 94. The surface of the metal plate 50 forms the top surface 3a of the IC card 3. The surface of the metal plate 10 forms the back surface 3b of the IC card 3. The other basic configuration is the same as that of the IC card 2 shown in FIGS. 1 to 4, so the same elements are designated by the same reference numerals and redundant explanations will be omitted.

[0049] Fig. 10 is a schematic plan view illustrating the configuration of an antenna device 1 that can be used in an IC card 3 according to a first modified example. Note that line CC shown in Fig. 10 indicates the cross-sectional position of Fig. 9. Fig. 11 is a schematic plan view illustrating the shapes of magnetic bodies 20 and 40 used in an IC card 3 according to a first modified example.

[0050] 10 does not include a coil pattern 120, and has a configuration in which an outer peripheral end 131 and an inner peripheral end 132 of a coil pattern 110 are arranged within an opening region 110a. The outermost turn of the coil pattern 110 and the outer peripheral end 131 are connected via a connection pattern 130 provided on the rear surface 32 of the substrate 30. As shown in FIG. 9, the outer peripheral end 131 of the coil pattern 110 is connected to a connection terminal 93 of the IC module 90 via solder 95, and the inner peripheral end 132 of the coil pattern 110 is connected to a connection terminal 94 of the IC module 90 via solder 95.

[0051] As illustrated in the first modification, it is not necessary to electromagnetically couple the IC module and the coil conductor, and they may be electrically connected directly. In this case, an anisotropic conductive material may be used instead of solder 95 to connect them. In this case, it is not necessary to interpose the magnetic body 20 at a position overlapping the through hole 48 of the magnetic body 40. Furthermore, in the first modification shown in FIG. 9, the contact-type IC module 90 is disposed inside the through hole 48 of the magnetic body 40. However, as in the example shown in FIG. 3, a through hole 51 may be formed in the metal plate 50 and the contact-type IC module 90 may be disposed inside the through hole 51.

[0052] Furthermore, in the first modified example, the magnetic body 40 does not overlap with the fourth section 114, the fifth section 115, the sixth section 116, the seventh section 117, and the eighth section 118 of the coil pattern 110, and the outer edges E5 and E6 of the magnetic body 40 are located within the opening region 110a. Similarly, in the first modified example, the magnetic body 20 does not overlap with the first section 111, the second section 112, the third section 113, the fourth section 114, and the eighth section 118 of the coil pattern 110, and the outer edges E7 and E8 of the magnetic body 20 are located within the opening region 110a. With this configuration, the magnetic flux components that bypass the magnetic body 40 without interlinking with the coil pattern 110 and the magnetic flux components that bypass the magnetic body 20 without interlinking with the coil pattern 110 are further reduced, making it possible to link even more magnetic flux to the coil pattern 110.

[0053] In the first modified example, the first cutout region 47 of the magnetic body 40 does not overlap with the magnetic body 20, and the second cutout region 27 of the magnetic body 20 does not overlap with the magnetic body 40. In this way, the first cutout region 47 of the magnetic body 40 does not need to overlap with the magnetic body 20, and the second cutout region 27 of the magnetic body 20 does not need to overlap with the magnetic body 40.

[0054] FIG. 12 is a schematic plan view for explaining the shapes of the magnetic bodies 20 and 40 according to the second modified example.

[0055] The second modified example differs from the structure shown in Fig. 11 in that the size of first region 41 of magnetic body 40 in the Y direction is enlarged, and outer peripheral edge E5 of magnetic body 40 overlaps with edge 27a that defines second cutout region 27 of magnetic body 20. In other words, the position of outer peripheral edge E5 in the Y direction is approximately the same as the position of edge 27a in the Y direction. Since the other basic configuration is the same as the structure shown in Fig. 11, the same elements are designated by the same reference numerals and redundant explanations will be omitted.

[0056] As illustrated in the second modified example, the outer peripheral edge E5 and the edge 27a may overlap. Similarly, the outer peripheral edge E7 and the edge 47a may overlap, the outer peripheral edge E6 and the edge 27b may overlap, and the outer peripheral edge E8 and the edge 47b may overlap.

[0057] FIG. 13 is a schematic plan view for explaining the shapes of the magnetic bodies 20 and 40 according to the third modified example.

[0058] The third modified example differs from the structure shown in FIG. 11 in that a region 44 is added to the magnetic body 40 and a region 28 is added to the magnetic body 20. The region 44 protrudes in the −X direction from the first region 41 and overlaps with the seventh section 117 of the coil pattern 110. The region 28 protrudes in the +X direction from the fourth region 24 and overlaps with the third section 113 of the coil pattern 110. The other basic configuration is the same as the structure shown in FIG. 11, so the same elements are denoted by the same reference numerals and redundant explanations will be omitted.

[0059] As illustrated in the third modified example, the planar shape of the magnetic bodies 20 and 40 does not have to be substantially L-shaped and may be substantially T-shaped. Although the region 44 overlaps with the seventh section 117 of the coil pattern 110, it does not have to include a portion extending beyond the seventh section 117 of the coil pattern 110 to an area outside the coil pattern 110. Furthermore, although the region 28 overlaps with the third section 113 of the coil pattern 110, it does not have to include a portion extending beyond the third section 113 of the coil pattern 110 to an area outside the coil pattern 110. This makes it possible to reduce magnetic flux components that bypass the magnetic body 40 without interlinking with the coil pattern 110 and magnetic flux components that bypass the magnetic body 20 without interlinking with the coil pattern 110.

[0060] FIG. 14 is a schematic plan view for explaining the shapes of the magnetic bodies 20 and 40 according to the fourth modified example.

[0061] The fourth modified example differs from the structure shown in FIG. 13 in that a region 45 is further added to the magnetic body 40, and a region 29 is further added to the magnetic body 20. Region 45 protrudes in the −Y direction from the first region 41, and overlaps with the fifth section 115 of the coil pattern 110. Region 29 protrudes in the +Y direction from the fourth region 24, and overlaps with the first section 111 of the coil pattern 110. The other basic configuration is the same as the structure shown in FIG. 12, so the same elements are given the same symbols and redundant explanations will be omitted.

[0062] As illustrated in the fourth modified example, the planar shape of the magnetic bodies 20 and 40 may be substantially cross-shaped. Although the region 45 overlaps with the fifth section 115 of the coil pattern 110, it does not have to include a portion extending beyond the fifth section 115 of the coil pattern 110 to an area outside the coil pattern 110. Furthermore, although the region 29 overlaps with the first section 111 of the coil pattern 110, it does not have to include a portion extending beyond the first section 111 of the coil pattern 110 to an area outside the coil pattern 110. This makes it possible to reduce magnetic flux components that bypass the magnetic body 40 without interlinking with the coil pattern 110 and magnetic flux components that bypass the magnetic body 20 without interlinking with the coil pattern 110.

[0063] FIG. 15 is a schematic plan view for explaining the shapes of the magnetic bodies 20 and 40 according to the fifth modified example.

[0064] In the fifth modified example, the shapes of the first cutout region 47 and the second cutout region 27 differ from those of the structure shown in Fig. 10. The other basic configuration is the same as the structure shown in Fig. 10, so the same elements are given the same reference numerals and redundant explanations will be omitted.

[0065] In the fifth modified example, angle θ1 formed by edges 47a and 47b that define first cutout region 47 is an acute angle, and angle θ2 formed by edges 27a and 27b that define second cutout region 27 is an acute angle. This further reduces the magnetic flux components that bypass magnetic body 40 without interlinking with coil pattern 110 and the magnetic flux components that bypass magnetic body 20 without interlinking with coil pattern 110, making it possible to further improve antenna characteristics.

[0066] FIG. 16 is a schematic plan view for explaining the shapes of the magnetic bodies 20 and 40 according to the sixth modified example.

[0067] The sixth modified example differs from the structure shown in Fig. 10 in that the first cutout region 47 of the magnetic body 40 and the through hole 48 are integrated. Since the other basic configurations are the same as those shown in Fig. 10, the same elements are given the same reference numerals and redundant explanations will be omitted.

[0068] As illustrated in the sixth modified example, the first cutout region 47 and the through hole 48 of the magnetic body 40 do not need to be independent of each other, and the first cutout region 47 and the through hole 48 of the magnetic body 40 may be integrated. This further reduces the magnetic flux component that bypasses the magnetic body 40 without interlinking with the coil pattern 110.

[0069] FIG. 17 is a schematic plan view for explaining the shapes of the magnetic bodies 20 and 40 according to the seventh modified example.

[0070] The seventh modified example differs from the structure shown in Fig. 10 in that there is no overlap between the first region 41 of the magnetic body 40 and the fourth region 24 of the magnetic body 20. Since the other basic configurations are the same as those shown in Fig. 10, the same elements are given the same reference numerals and redundant explanations will be omitted.

[0071] As illustrated in the seventh modified example, it is not essential that the first region 41 of the magnetic body 40 and the fourth region 24 of the magnetic body 20 overlap, and it is also acceptable for the first region 41 of the magnetic body 40 and the fourth region 24 of the magnetic body 20 not to overlap.

[0072] FIG. 18 is a YZ cross-sectional view of an IC card 4 according to an eighth modified example.

[0073] As shown in Fig. 18, the IC card 4 according to the eighth modification differs from the IC card 2 shown in Figs. 1 to 4 in that a third spacer 73 and a fourth spacer 74 are added. The third spacer 73 is located between the magnetic body 40 and the metal plate 50, and the fourth spacer 74 is located between the magnetic body 20 and the metal plate 10. The surface of the metal plate 50 forms the top surface 4a of the IC card 4. The surface of the metal plate 10 forms the back surface 4b of the IC card 4. The other basic configuration is the same as that of the IC card 2 shown in Figs. 1 to 4, so the same elements are given the same reference numerals and redundant explanations will be omitted.

[0074] As illustrated in the eighth modified example, by placing a third spacer 73 between the magnetic body 40 and the metal plate 50 and a fourth spacer 74 between the magnetic body 20 and the metal plate 10, the distance in the Z direction between the coil pattern 110 and the metal plates 10 and 50 becomes greater, making it possible to suppress eddy currents occurring in the metal plates 10 and 50.

[0075] The above describes embodiments of the technology according to the present disclosure, but the technology according to the present disclosure is not limited to the above embodiments, and various modifications are possible within the scope of the gist of the technology, and it goes without saying that these modifications are also included within the scope of the technology according to the present disclosure.

[0076] For example, in the above embodiment, the coil conductor is configured by a coil pattern formed on the surface of the substrate, but a coil conductor formed by winding a conducting wire may also be used.

[0077] The technology according to the present disclosure includes, but is not limited to, the following configuration examples.

[0078] An antenna device according to one aspect of the present disclosure comprises a coil conductor, a first magnetic body arranged on one side of the coil conductor in the axial direction, and a second magnetic body arranged on the other side of the coil conductor in the axial direction, wherein the first magnetic body has a first region overlapping with an opening region of the coil conductor when viewed from the axial direction, a second region protruding from the first region to one side in the first direction and overlapping with the coil conductor, and a third region protruding from the first region to one side in a second direction perpendicular to the first direction and overlapping with the coil conductor, the second magnetic body has a fourth region overlapping with the opening region of the coil conductor when viewed from the axial direction, a fifth region protruding from the fourth region to the other side in the first direction and overlapping with the coil conductor, and a sixth region protruding from the fourth region to the other side in the second direction and overlapping with the coil conductor, and the first magnetic body has a first notch region whose outer edge is located inside a first intersection between a first virtual line extending an outer peripheral edge of the second region in the second direction and a second virtual line extending an outer peripheral edge of the third region in the first direction. This makes it possible to reduce the magnetic flux component that bypasses the first magnetic body without interlinking with the coil conductor.

[0079] In the antenna device, the second region of the first magnetic body may include a portion extending to the outer region of the coil conductor, and the third region of the first magnetic body may include a portion extending to the outer region of the coil conductor, thereby making it possible to link more of the magnetic flux in the first and second directions to the coil conductor.

[0080] In the antenna device, the outer peripheral edge of the first region of the first magnetic body, which is located on the opposite side to the second region, may be located inside the outer region of the coil conductor, thereby making it possible to further reduce the magnetic flux component that bypasses the first magnetic body in the first direction without interlinking with the coil conductor.

[0081] In the antenna device, the outer peripheral edge of the first region of the first magnetic body, which is located on the opposite side to the third region, may be located inside the outer region of the coil conductor, thereby making it possible to further reduce the magnetic flux component that bypasses the first magnetic body in the second direction without interlinking with the coil conductor.

[0082] In the above antenna device, the second magnetic body may have a second cutout region whose outer peripheral edge is located inside a second intersection point between a third virtual line extending from the outer peripheral edge of the fifth region in the second direction and a fourth virtual line extending from the outer peripheral edge of the sixth region in the first direction. This makes it possible to reduce magnetic flux components that bypass the second magnetic body without interlinking with the coil conductor.

[0083] In the above antenna device, the outer peripheral edge of the second magnetic body located on the opposite side of the fourth region from the fifth region may be located inside the outer peripheral region of the coil conductor, and the outer peripheral edge of the second magnetic body located on the opposite side of the fourth region from the sixth region may be located inside the outer peripheral region of the coil conductor. This makes it possible to further reduce magnetic flux components that bypass the second magnetic body in the first and second directions without interlinking with the coil conductor.

[0084] In the antenna device, the first region of the first magnetic body and the fourth region of the second magnetic body may overlap each other when viewed from the axial direction, thereby reducing the magnetic resistance between the first magnetic body and the second magnetic body.

[0085] In the antenna device, the first cutout region of the first magnetic body may overlap the opening region of the coil conductor, which makes it possible to further reduce the magnetic flux component that bypasses the first magnetic body without interlinking with the coil conductor.

[0086] In the antenna device, the second cutout region of the second magnetic body may overlap with the opening region of the coil conductor, which makes it possible to further reduce the magnetic flux component that bypasses the second magnetic body without interlinking with the coil conductor.

[0087] In the antenna device, the first cutout region of the first magnetic body may overlap with the fourth region of the second magnetic body, thereby further reducing the magnetic resistance between the first magnetic body and the second magnetic body.

[0088] In the above antenna device, the thickness of the first and second magnetic bodies may be greater than the thickness of the coil conductor, which makes it possible to further increase the magnetic flux that links with the coil conductor.

[0089] The antenna device may further include a first spacer that is disposed in the same plane as the first magnetic body and overlaps with the second magnetic body when viewed from the axial direction, thereby improving the flatness of one surface side of the antenna device.

[0090] The antenna device may further include a second spacer that is disposed in the same plane as the second magnetic body and overlaps with the first magnetic body when viewed from the axial direction, thereby improving the flatness of the other surface side of the antenna device.

[0091] An IC card according to an embodiment of the present disclosure includes the antenna device described above, making it possible to provide an IC card capable of wireless communication.

[0092] The IC card may further include a first card substrate made of metal and a second card substrate made of metal, and the antenna device may be disposed between the first card substrate and the second card substrate, thereby providing an IC card with both sides made of metal.

[0093] The IC card may further include a third spacer disposed between the first magnetic body and the first card substrate, and a fourth spacer disposed between the second magnetic body and the second card substrate, in the axial order of the first card substrate, the first magnetic body, the second magnetic body, and the second card substrate. This increases the axial distance between the first card substrate and the first magnetic body, and increases the axial distance between the second card substrate and the second magnetic body, thereby suppressing eddy currents generated in the first and second card substrates. [Explanation of symbols]

[0094] 1 Antenna device 2~4 IC cards 2a, 3a, 4a Top of IC card 2b, 3a, 4a Back of IC card 6. Card Reader 10,50 Metal Plate 20,40 Magnetic material 24 4th area 24a Edge of the 4th Region 25 5th area 26 Area 6 27 Second notch area 27a, 27b Edge of second notch area 28,29 area 30 Base material 31 Surface of the substrate 32 Back side of substrate 41 First area 41a Edge of the first region 42 Second area 43 Third area 44,45 area 47 First notch area 47a, 47b Edge of first notch area 48,51 Through holes 60 IC modules 61 Module Board 62 IC chips 63 Coupling coil 64 Protective Resin 71 First spacer 72 Second spacer 73 Third spacer 74 4th spacer 81,82 Adhesive layer 90 IC modules 91 Module Board 92 IC chips 93,94 Connection terminal 95 Solder 100 Coil conductor 101,131 Outer end of coil conductor 102,132 Inner end of coil conductor 110,120 coil pattern 110a opening area E terminal electrode E1~E8 outer edge L1~L4 virtual lines P1,P2 intersection φ1,φ2 magnetic flux

Claims

1. A coil conductor; a first magnetic body disposed on one side in the axial direction as viewed from the coil conductor; a second magnetic body disposed on the other side of the coil conductor in the axial direction; Equipped with the first magnetic body has a first region overlapping an opening region of the coil conductor when viewed from the axial direction, a second region protruding from the first region to one side in a first direction and overlapping with the coil conductor, and a third region protruding from the first region to one side in a second direction perpendicular to the first direction and overlapping with the coil conductor, the second magnetic body has a fourth region overlapping with an opening region of the coil conductor when viewed from the axial direction, a fifth region protruding from the fourth region to the other side in the first direction and overlapping with the coil conductor, and a sixth region protruding from the fourth region to the other side in the second direction and overlapping with the coil conductor, an antenna device, wherein the first magnetic body has a first cutout region in which the outer edge is located inside a first intersection point between a first virtual line extending the outer edge of the second region in the second direction and a second virtual line extending the outer edge of the third region in the first direction.

2. the second region of the first magnetic body includes a portion extending to an outer region of the coil conductor, the third region of the first magnetic body includes a portion extending to an outer region of the coil conductor. The antenna device according to claim 1 .

3. an outer peripheral edge of the first magnetic body located on the opposite side to the second region in the first region is located inside the outer region of the coil conductor; The antenna device according to claim 2 .

4. an outer peripheral edge of the first magnetic body located on the opposite side of the third region in the first region is located inside the outer region of the coil conductor; The antenna device according to claim 3 .

5. the second magnetic body has a second cutout region in which the outer peripheral edge is located inside a second intersection point between a third virtual line extending from the outer peripheral edge of the fifth region in the second direction and a fourth virtual line extending from the outer peripheral edge of the sixth region in the first direction; The antenna device according to claim 1 .

6. an outer peripheral edge of the second magnetic body in the fourth region opposite to the fifth region is located inside the outer region of the coil conductor; an outer peripheral edge of the second magnetic body in the fourth region opposite to the sixth region is located inside the outer region of the coil conductor; 6. The antenna device according to claim 5.

7. the first region of the first magnetic body and the fourth region of the second magnetic body overlap each other when viewed from the axial direction; The antenna device according to claim 1 .

8. the first cutout region of the first magnetic body overlaps with the opening region of the coil conductor; The antenna device according to claim 1 .

9. the second cutout region of the second magnetic body overlaps with the opening region of the coil conductor; 5. The antenna device according to claim 4.

10. the first cutout region of the first magnetic body overlaps with the fourth region of the second magnetic body; 9. The antenna device according to claim 8.

11. The thickness of the first and second magnetic bodies is greater than the thickness of the coil conductor. The antenna device according to claim 1 .

12. a first spacer disposed in the same plane as the first magnetic body and overlapping with the second magnetic body when viewed from the axial direction; 12. An antenna device according to any one of claims 1 to 11.

13. a second spacer disposed in the same plane as the second magnetic body and overlapping with the first magnetic body when viewed from the axial direction; 13. The antenna device according to claim 12.

14. An IC card comprising the antenna device according to any one of claims 1 to 11.

15. a first card substrate made of metal; a second card substrate made of metal; Furthermore, the antenna device is disposed between the first card substrate and the second card substrate; The IC card according to claim 14.

16. the first card substrate, the first magnetic body, the second magnetic body, and the second card substrate are arranged in this order in the axial direction; a third spacer disposed between the first magnetic body and the first card substrate; a fourth spacer disposed between the second magnetic body and the second card substrate; Further provided with 16. The IC card according to claim 15.

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