Antenna device and IC card

Abstract

To provide an antenna device and an IC card that can restrain visibility.SOLUTION: An antenna device 1 includes a conductor pattern 14. The conductor pattern includes an opening 20 and a slit 21 extending from the opening 20 to an edge 14c of the conductor pattern 14, as an area where a first conductive wire 30 and a second conductive wire 31 are not formed. A width of the slit 21 is smaller than a width of the opening 20. An open mesh part 17B arranged at edge parts 21a, 21b of the slit 21 is open to the slit 21, and thus formation of the mesh part 17 with a narrow pitch can be suppressed.SELECTED DRAWING: Figure 5

Description

[Technical field]

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

[0002] Conventionally, an antenna device including a mesh-shaped conductor pattern is known (for example, see Patent Document 1). In this antenna device, a notch is formed in a location where an IC chip is to be disposed. [Prior art documents] [Patent documents]

[0003] [Patent Document 1] JP 2014-7655 A Summary of the Invention [Problem to be solved by the invention]

[0004] In the antenna device described above, a conductive line is formed on the edge of the cutout portion so as to extend along the edge. In this case, the conductive line along the edge narrows the mesh pitch, which causes a problem that the conductive pattern in the cutout portion becomes easily visible.

[0005] Therefore, an object of the present disclosure is to provide an antenna device and an IC card that can reduce visibility. [Means for solving the problem]

[0006] An antenna device according to one aspect of the present disclosure is an antenna device including a mesh-shaped conductor pattern having a plurality of mesh portions, the conductor pattern including a plurality of first conductive lines extending in a first direction and a plurality of second conductive lines extending in a second direction intersecting the first direction, the conductor pattern having an opening and a slit extending from the opening to an edge of the conductor pattern as an area in which the first conductive lines and the second conductive lines are not formed, the width of the slit being smaller than the width of the opening, and at least a portion of the mesh portion arranged on the edge of the slit being open to the slit.

[0007] An IC card according to one aspect of the present disclosure includes the above-mentioned antenna device and an IC module placed in the opening. Effect of the Invention

[0008] According to one aspect of the present disclosure, it is possible to provide an antenna device and an IC card capable of suppressing visibility. [Brief description of the drawings]

[0009] [Figure 1] 1 is a schematic perspective view showing the appearance of an IC card incorporating an antenna device according to an embodiment of the present disclosure. [Diagram 2] FIG. 2 is an exploded perspective view of the IC card as viewed from the bottom side. [Diagram 3] FIG. 2 is a cross-sectional view taken along line III-III shown in FIG. [Figure 4] FIG. 2 is a plan view of the antenna device. [Diagram 5] FIG. 4 is an enlarged view of the vicinity of a connection portion between a slit and an opening portion. [Figure 6] 11 is an enlarged view showing a conductor pattern of an antenna device according to a comparative example. [Figure 7] FIG. 13 is a plan view of an antenna device according to a modified example. [Figure 8] FIG. 11 is a cross-sectional view of an antenna device according to a modified example. [Figure 9] FIG. 11 is a cross-sectional view of an antenna device according to a modified example. [Figure 10] FIG. 11 is a cross-sectional view of an antenna device according to a modified example. DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

[0010] Hereinafter, several embodiments of the present disclosure will be described in detail. However, the present disclosure is not limited to the following embodiments.

[0011] Fig. 1 is a schematic perspective view showing the appearance of an IC card 100 incorporating an antenna device according to an embodiment of the present disclosure. The IC card 100 shown in Fig. 1 is a plate-like body with the y-axis direction as the short side direction, the x-axis direction as the long side direction, and the z-axis direction as the thickness direction, and has an upper surface a and a lower surface b that form an xy plane. The IC card 100 incorporates an IC module 50 and an antenna device, which will be described later, and a terminal electrode E of the IC module is exposed on the upper surface a of the IC card 100. The IC card 100 can communicate via the antenna device by facing the lower surface b to a card reader 110.

[0012] FIG. 2 is an exploded perspective view of the IC card 100 as viewed from the bottom surface b side. FIG. 3 is a cross-sectional view taken along line III-III shown in FIG. 1. FIG. 3 shows a structure in the vicinity of an IC module 50. As shown in FIGS. 2 and 3, the IC card 100 has a structure in which a cover layer 2, an antenna device 1, and a cover layer 3 are laminated in this order from the top surface a side toward the bottom surface b side. The IC card 100 also includes an IC module 50. In this embodiment, the IC module 50 is disposed in a region of the IC card 100 on the negative side in the X-axis direction, closer to the positive side in the Y-axis direction. However, the position of the IC module 50 is not particularly limited.

[0013] The cover layer 2 is a plate-like member that covers the main surface 1a on the positive side in the z-axis direction of the antenna device 1. The surface of the cover layer 2 on the positive side in the z-axis direction constitutes the upper surface a of the IC card 100. The cover layer 2 is provided with a substantially rectangular opening 4. The opening 4 penetrates the cover layer 2 in the thickness direction (Z-axis direction). An IC module 50 is disposed inside the opening 10 (see FIG. 3). The cover layer 3 is a plate-like member that covers the main surface 1b on the negative side in the z-axis direction of the antenna device 1. The surface of the cover layer 3 on the negative side in the z-axis direction constitutes the lower surface b of the IC card 100. The cover layer 2 is bonded to the antenna device 1 via an adhesive layer 11. The surface of the cover layer 3 on the negative side in the z-axis direction constitutes the lower surface b of the IC card 100. The cover layer 3 is bonded to the antenna device 1 via an adhesive layer 12.

[0014] The cover layers 2, 3 may be transparent resin substrates. The cover layers 2, 3 may be made of, for example, cellulose propionate (CP), polyvinyl chloride (PVD), polycarbonate (PC), reinforced glass, etc. The thickness of the cover layers 2, 3 is not particularly limited, but may be 200 to 400 μm. The total light transmittance of the cover layers 2, 3 may be 90 to 100%.

[0015] The adhesive layers 11 and 12 are layers formed by filling with an adhesive. The adhesive layers 11 and 12 may be made of an acrylic adhesive, a urethane adhesive, or the like. The adhesive layers 11 and 12 may be free of a base material, have a high total light transmittance, and have a low haze. The thickness of the adhesive layers 11 and 12 is not particularly limited, but may be 10 to 100 μm. The adhesive layers 11 and 12 may have a total light transmittance of 90 to 100%.

[0016] Fig. 4 is a plan view of the antenna device 1. As shown in Fig. 4, the antenna device 1 is a rectangular plate-shaped member. The antenna device 1 has an edge 1c on the negative side in the x-axis direction, an edge 1d on the positive side in the x-axis direction, an edge 1e on the negative side in the y-axis direction, and an edge 1f on the positive side in the y-axis direction. In this embodiment, the edges 1c and 1d are short sides, and the edges 1e and 1f are long sides.

[0017] The antenna device 1 includes a mesh-shaped conductor pattern 14 having a plurality of mesh portions 17 (see FIG. 3 and FIG. 5). The conductor pattern 14 is a mesh-shaped pattern including a plurality of regularly arranged mesh portions 17 (see FIG. 3 and FIG. 5) formed by a plurality of conductive lines intersecting each other. The configuration of the pattern of the conductor pattern 14 will be described in detail later. The conductor pattern 14 is formed on substantially the entire surface of the main surface 1a of the antenna device 1. The conductor pattern 14 has a rectangular shape corresponding to the shape of the main surface 1a. The conductor pattern 14 has a negative edge 14c in the x-axis direction, a positive edge 14d in the x-axis direction, a negative edge 14e in the y-axis direction, and a positive edge 14f in the y-axis direction. Each edge 14c, 14d, 14e, 14f extends parallel to each edge 1c, 1d, 1e, 1f, and is disposed on the inner periphery side from each edge 1c, 1d, 1e, 1f. However, each of the edges 14c, 14d, 14e, and 14f may be disposed without any gap from each of the edges 1c, 1d, 1e, and 1f. Furthermore, the shape and size of the conductor pattern 14 are not particularly limited as long as it can function as an antenna.

[0018] In the conductive pattern 14, an opening 20 and a slit 21 extending from the opening 20 to an edge 14c of the conductive pattern 14 are formed as regions where conductive lines (a first conductive line and a second conductive line described later) are not formed. The opening 20 is formed at a position where the IC module 50 is disposed. The opening 20 has a rectangular shape corresponding to the shape of the IC module 50. The slit 21 extends from a side portion on the negative side in the x-axis direction of the opening 20 to an edge portion 14c on the negative side in the x-axis direction of the conductive pattern 14. The slit 21 extends parallel to the x-axis direction with a constant width. The width of the slit 21 and the width of the opening 20 are dimensions in a direction perpendicular to the extending direction and the penetrating direction of the slit 21, that is, the distance between the edges extending along the extending direction of the slit 21. The width of the slit 21 (dimension in the y-axis direction) is smaller than the width of the opening 20 (dimension in the y-axis direction). The opening 20 and the slit 21 are configured as through-holes penetrating the antenna device 1 from the principal surface 1a to the principal surface 1b. The slit 21 extends from the opening 20 to the edge 1c, and the end of the slit 21 in the x-direction is open to the outer periphery at the edge 1c.

[0019] As shown in Fig. 3, the antenna device 1 includes a substrate 13, a conductor pattern 14 provided on one first principal surface 13a of the substrate 13, and a resin layer 16 provided on the first principal surface 13a of the substrate 13. The conductor pattern 14 extends in a direction along the first principal surface 13a of the substrate 13 and has a plurality of mesh portions 17. The conductor pattern 14 has conductor portions 18 that form the mesh portions 17. The resin layer 16 is disposed between the plurality of conductor portions 18, i.e., within the mesh portions 17. In Fig. 3, the conductor portions 18 are shown in a deformed state, and the width and pitch of the conductor portions 18 are shown in an adjusted state.

[0020] The substrate 13 has a degree of light transmittance required for the antenna device 1. Specifically, the total light transmittance of the substrate 13 may be 90 to 100%. The haze of the substrate 13 may be 0 to 5%.

[0021] The substrate 13 may be, for example, a transparent resin film, examples of which include a film of polyethylene terephthalate (PET), polycarbonate (PC), polyethylene naphthalate (PEN), cycloolefin polymer (COP), or polyimide (PI). Alternatively, the substrate 13 may be a glass substrate.

[0022] The thickness of the substrate 13 may be 10 μm or more, 20 μm or more, or 35 μm or more, and may be 500 μm or less, 200 μm or less, or 100 μm or less.

[0023] The conductor section 18 may contain a metal. The conductor section 18 may contain at least one metal selected from copper, nickel, cobalt, palladium, silver, gold, platinum, and tin, or may contain copper. The conductor section 18 may be a metal plating formed by a plating method. The conductor section 18 may further contain a nonmetallic element such as phosphorus within a range in which appropriate conductivity is maintained.

[0024] The resin layer 16 is made of a light-transmitting resin and is provided so as to fill the mesh portion 17, and usually, the resin layer 16 and the conductor portion 18 form a flat surface.

[0025] The resin layer 16 is formed of a resin having optical transparency. The resin layer 16 may have a total light transmittance of 90 to 100%. The resin layer 16 may have a haze of 0 to 5%.

[0026] The resin forming the resin layer 16 may be a cured product of a curable resin composition (a photocurable resin composition or a thermosetting resin composition). The curable resin composition forming the resin layer 16 includes a curable resin, examples of which include an acrylic resin, an amino resin, a cyanate resin, an isocyanate resin, a polyimide resin, an epoxy resin, an oxetane resin, a polyester, an allyl resin, a phenol resin, a benzoxazine resin, a xylene resin, a ketone resin, a furan resin, a COPNA resin, a silicon resin, a dicyclopentadiene resin, a benzocyclobutene resin, an episulfide resin, an ene-thiol resin, a polyazomethine resin, a polyvinylbenzyl ether compound, an acenaphthylene, and an ultraviolet-curable resin containing a functional group that undergoes a polymerization reaction with ultraviolet light, such as an unsaturated double bond, a cyclic ether, or a vinyl ether.

[0027] In the opening 20 and the slit 21 (see FIG. 4), a through hole is formed penetrating the resin layer 16 and the base material 13 in the z-axis direction. Therefore, the opening 20 and the slit 21 (see FIG. 4) are areas where the resin layer 16, the base material 13, and the conductor pattern 14 are not present. In the antenna device 1 in a state before being assembled into the IC card 100, a space SP is provided in the opening 20 and the slit 21 (see FIG. 2). In the antenna device 1 in a state after being assembled into the IC card 100, the space SP in the opening 20 is filled with the adhesive of the adhesive layers 11, 12.

[0028] The IC module 50 includes a module substrate 51 and an IC chip 52 mounted or built into the module substrate 51, and a coupling coil 53 is formed on the negative surface in the z-axis direction of the module substrate 51 (see also FIG. 2). A terminal electrode E shown in FIG. 1 is provided on the front surface side of the module substrate 51. The IC chip 52 may be covered with a resin 54.

[0029] The IC module 50 is disposed in the opening 4 of the cover layer 2. The inner peripheral surface of the opening 4 is disposed so as to surround the IC module 50 from the outer peripheral side. The IC module 50 is disposed so as to face the opening 20 of the antenna device 1 at a position on the positive side in the z-axis direction. The size of the opening 20 in the y-axis direction and the x-axis direction is smaller than that of the IC module 50. In addition, the size of the opening 20 in the y-axis direction and the x-axis direction is smaller than that of the edge 53a on the outer peripheral side of the coupling coil 53 and larger than that of the edge 53b on the inner peripheral side of the coupling coil 53. Therefore, when viewed from the z-axis direction, the four inner peripheral surfaces 20e of the opening 20 are disposed so as to overlap with the four sides of the coupling coil 53.

[0030] Next, the function of the antenna device 1 will be described with reference to FIG. 4. A current CA flows through the coupling coil 53 (see FIG. 2) of the IC module 50. In FIG. 4, the current CA flows counterclockwise. At this time, the magnetic flux B (see FIG. 2) of the coupling coil 53 acts on the edge of the opening 20. As a result, a clockwise eddy current CB flows through the conductor pattern 14 near the edge of the opening 20. In this way, the conductor pattern 14 near the edge of the opening 20 functions as a coupling coil that is magnetically coupled to the coupling coil 53 of the IC module 50. Here, the conductor pattern 14 at the edge on the negative side in the x-axis direction of the opening 20 is divided by the slit 21 up to the edge 14c. Therefore, the eddy current CB is divided by the slit 21, and currents CCa and CCb flow in the x-axis direction along the slit 21. A current CCa flows from the opening 20 toward the edge 14c side through the conductor pattern 14 at the edge on the negative side in the y-axis direction of the slit 21. As a result, a counterclockwise current CD flows through the entire conductor pattern 14. A current CCb flows through the conductor pattern 14 at the edge of the slit 21 on the positive side in the y-axis direction from the edge 14c side back to the opening 20. As described above, a current flows through the entire conductor pattern 14 of the antenna device 1 in the same direction as the IC module 50, allowing the antenna device 1 to function as an antenna.

[0031] Next, the conductor pattern 14 will be described in detail with reference to Fig. 5. Fig. 5 is an enlarged view of the vicinity of the connection between the slit 21 and the opening 20. Fig. 5 shows the edge 21a on the negative side in the y-axis direction of the slit 21 and the edge 21b on the positive side in the y-axis direction. Also shown are the edge 20a on the negative side in the y-axis direction of the opening 20, the edge 20b on the positive side in the y-axis direction, and the edge 20c on the negative side in the x-axis direction. The edges 20a, 20b, 21a, and 21b extend parallel to the x-axis direction. The edge 20c extends parallel to the y-axis direction.

[0032] As shown in FIG. 5, the conductor pattern 14 includes a plurality of first conductive wires 30 and a plurality of second conductive wires 31. The first conductive wires 30 are linear conductor portions 18 extending parallel to the x-axis direction (first direction). The plurality of first conductive wires 30 are arranged so as to be spaced apart from one another in the y-axis direction. The plurality of first conductive wires 30 are arranged so as to be spaced apart at an equal pitch. The second conductive wires 31 are linear conductor portions 18 extending parallel to the y-axis direction (second direction). The plurality of second conductive wires 31 are arranged so as to be spaced apart from one another in the x-axis direction. The plurality of second conductive wires 31 are arranged so as to be spaced apart at an equal pitch. The line width of the conductive wires 30, 31 is not particularly limited, but may be set to, for example, 1 to 3 μm. The pitch of the conductive wires 30, 31 is also not particularly limited, but may be set to, for example, 50 to 200 μm. The first conductive wire 30 and the second conductive wire 31 have a line thickness greater than their line width. The line thickness of the conductive wires 30, 31 is the dimension in the z-axis direction. Therefore, the cross-sectional shape of the conductive wires 30, 31 has a shape extending in the z-axis direction (see FIG. 3). The line thickness of the conductive wires 30, 31 is not particularly limited, but may be set to, for example, 2 to 5 μm. The ends of the conductive wires 30, 31 in the z-axis direction may or may not coincide with the surface of the resin layer 16 in the z-axis direction.

[0033] In this embodiment, the first conductive wire 30 is approximately parallel to the x-axis direction, which is the extension direction of the slit 21. The other, second conductive wire 31, is approximately perpendicular to the x-axis direction, which is the extension direction. Note that the first conductive wire 30 does not have to be parallel to the x-axis direction as long as it extends in the x-axis direction, and the second conductive wire 31 does not have to be parallel to the y-axis direction as long as it extends in the y-axis direction.

[0034] A description will be given of the normal mesh portion 17 other than the vicinity of the slit 21 and the vicinity of the opening 20. Each mesh portion 17 is composed of a pair of adjacent first conductive wires 30 and a pair of adjacent second conductive wires 31. Such a mesh portion 17 may be referred to as a normal mesh portion 17A. In this embodiment, each mesh portion 17 has a square shape. However, if the pitch of the first conductive wires 30 and the pitch of the second conductive wires 31 are different from each other, the mesh portion 17 has a rectangular shape. In the mesh portion 17, a resin layer 16 (FIG. 3) is disposed in the internal space surrounded by the conductive wires 30, 31 on all four sides. The pitch of the mesh portion 17 in the y-axis direction is equal to the pitch of the first conductive wires 30. The pitch of the mesh portion 17 in the x-axis direction is equal to the pitch of the second conductive wires 31. The width (dimension in the y-axis direction) of the slit 21 may be larger than the pitch of the mesh portion 17 in the y-axis direction. The width of the slits 21 may be larger than the pitch of the mesh portion 17 in the x-axis direction. In the mesh portion 17, the first conductive wires 30 and the second conductive wires 31 only need to intersect, and are not necessarily perpendicular to each other. In other words, a mesh portion 17 in which the first conductive wires 30 and the second conductive wires 31 intersect at an angle may be used.

[0035] The mesh portion 17 arranged on the edges 21a and 21b of the slit 21 is open to the slit 21. Such a mesh portion 17 may be referred to as an open mesh portion 17B. No conductive wire extending in the x-axis direction along the edges 21a and 21b of the slit 21 is formed on the edges 21a and 21b of the slit 21. The end 31a of the second conductive wire 31 in the y-axis direction is present in an independent state on the edges 21a and 21b. Among the edges 21a and 21b, a resin layer 16 is present between the end 31a of the second conductive wire 31 and the end 31a of the adjacent second conductive wire 31. With this configuration, the open mesh portion 17B arranged on the edge 21a does not have a first conductive wire 30 extending in the x-axis direction on the positive side of the y-axis direction. Therefore, the open mesh portion 17B arranged at the edge portion 21a is surrounded by conductive wires on both sides in the negative y-axis direction and the x-axis direction, and is open to the slit 21 on the positive y-axis direction. The open mesh portion 17B arranged at the edge portion 21b does not have the first conductive wire 30 extending in the x-axis direction on the negative y-axis direction. Therefore, the open mesh portion 17B arranged at the edge portion 21b is surrounded by conductive wires on both sides in the positive y-axis direction and the x-axis direction, and is open to the slit 21 on the negative y-axis direction. However, the above-mentioned relationship does not need to be satisfied over the entire area of ​​the edges 21a and 21b of the slit 21. For example, a part of the slit 21 may be hidden by the IC module 50. In this case, the part of the edges 21a and 21b of the slit 21 that is hidden by the IC module 50 may not be open to the slit 21. The area of ​​the slit 21 that is hidden by the IC module 50 is the vicinity of the end of the slit 21 that is connected to the opening 20. It is preferable that the edges 21a, 21b of the slit 21 are open in areas other than the area hidden by the IC module 50. Therefore, when the total length of the edges 21a, 21b is taken as 100%, it is preferable that the open area is 80% or more.

[0036] In addition, in the conductor pattern 14 shown in FIG. 6, the first conductive wire 30 extends along the edges 21a and 21b of the slit 21. In such a structure, the mesh portion 17 arranged on the edge 21a and the mesh portion 17 arranged on the edge 21b are both surrounded by conductive wires on all four sides and are blocked by the first conductive wire 30 on the edges 21a and 21b with respect to the slit 21. Such a mesh portion 17 does not correspond to the mesh portion 17 opened to the slit 21. However, in the example shown in FIG. 5, both the edges 21a and 21b of the slit 21 are open to the slit 21. However, it is sufficient that at least one of the edges 21a and 21b is opened. In other words, due to design considerations, the other of the edges 21a and 21b may coincidentally be arranged at the position of the edge 21b, as in the edge 21b shown in FIG. 6.

[0037] The mesh portion 17 arranged at the edges 20a, 20b, and 20c of the opening 20 is open to the opening 20. The open mesh portion 17B arranged at the edges 20a and 20b of the opening 20 is open to the opening 20 in the same manner as the open mesh portion 17B arranged at the edges 21a and 21b of the slit 21. No conductive wire is formed on the edge 21c of the opening 20 extending in the y-axis direction along the edge 20c. The end 30a of the first conductive wire 30 in the x-axis direction is present in an independent state on the edge 20c. In the edge 20c, the resin layer 16 is present between the end 30a of the first conductive wire 30 and the end 30a of the adjacent first conductive wire 30. With this configuration, the open mesh portion 17B arranged at the edge 20c does not have a second conductive wire 31 extending in the y-axis direction on the positive side of the x-axis direction. Therefore, open mesh portion 17B arranged on edge 20c is surrounded by conductive wires on both the negative side in the x-axis direction and the y-axis direction, and has a structure that is open to opening 20 on the positive side in the x-axis direction. Note that open mesh portion 17B arranged on the edge of opening 20 on the positive side in the x-axis direction (not shown) is open to opening 20 on the negative side in the x-axis direction.

[0038] Next, the functions and effects of the antenna device 1 and the IC card 100 according to this embodiment will be described.

[0039] In the antenna device 1, the conductor pattern 14 has an opening 20 and a slit 21 extending from the opening 20 to an edge 14c of the conductor pattern 14 formed as a region where the first conductive wire 30 and the second conductive wire 31 are not formed. The width of the slit 21 is smaller than the width of the opening 20. If the first conductive wire 30 is provided along the edge 21a of the slit 21 as shown in FIG. 6 for such a slit 21, a mesh portion 17 having a narrower pitch than the normal mesh portion 17A is formed. In this case, the visibility in the vicinity of the edge 21a of the slit 21 increases.

[0040] 5, in the antenna device 1 according to this embodiment, at least a part of the open mesh portion 17B disposed on the edges 21a and 21b of the slit 21 is open to the slit 21. In this case, it is possible to prevent the formation of a mesh portion 17 with a narrow pitch. This makes it possible to reduce the visibility of the antenna device 1.

[0041] The mesh portion 17 disposed on the edge of the opening 20 may be open to the opening 20. In this case, it is possible to prevent the mesh portion 17 from being formed with a narrow pitch on the edge of the opening 20. This makes it possible to reduce visibility in the vicinity of the opening 20.

[0042] The first conductive line 30 and the second conductive line 31 may have a line thickness larger than the line width, which allows the formation of conductive lines with a high aspect ratio, thereby reducing the resistance while suppressing visibility in a plan view.

[0043] A resin (resin layer 16) is provided in the mesh portion 17, and a space SP may be formed in the opening 20. By providing the resin layer 16 in the mesh portion 17, it is possible to maintain the shape of the conductor pattern 14 and ensure flatness. Furthermore, by not providing the resin layer 16 in the opening 20, interference with the IC module 50 can be suppressed.

[0044] One of the first conductive wire 30 and the second conductive wire 31 may be substantially parallel to the extension direction of the slit 21, and the other may be substantially perpendicular to the extension direction. In this case, the communication characteristics of the antenna device 1 can be improved.

[0045] The width of the slit 21 may be larger than the pitch of the mesh portion 17. In this case, it is possible to obtain an effect that it is possible to suppress short-circuiting between the mesh portions 17 arranged on the edges on both sides of the slit 21 due to manufacturing errors or the like.

[0046] An IC card 100 according to one aspect of the present disclosure includes the above-mentioned antenna device 1 and an IC module 50 arranged in the opening 20.

[0047] According to this IC card 100, the same effects as those of the above-mentioned antenna device 1 can be obtained.

[0048] The present disclosure is not limited to the above-described embodiments.

[0049] For example, as shown in FIG. 7, a conductor section 40 having a line width wider than the first conductive wire 30 and the second conductive wire 31 may be arranged along the edge of the opening 20. The conductor section 40 has a rectangular ring shape by extending along the four edges of the opening 20. The conductor section 40 may be made of a conductive wire having a line width wider, or may be made of a mesh pattern having a narrower pitch than the normal mesh section 17A. As shown in FIG. 3, the edge of the opening 20 is hidden by overlapping with the coupling coil 53 of the IC module 50. Therefore, since there are cases where visibility is not affected, the resistance can be reduced by arranging a thick conductor section 40 at that location. Note that, when suppression of visibility near the edge of the opening 20 is required, the configuration shown in FIG. 5 may be adopted.

[0050] The configuration shown in FIG. 8 may be adopted. That is, a pair of ends 30a (see FIG. 5, first ends) of the first conductive wire 30 facing each other in the x-axis direction through the opening 20, and a pair of ends 31a (second ends) of the second conductive wire 31 facing each other in the y-axis direction through the opening 20 may have tapered shapes 45A, 45B that expand from one side to the other in the z-axis direction (thickness direction). The tapered shape 45A shown in FIG. 8(a) expands from the positive side to the negative side in the z-axis direction. The tapered shape 45B shown in FIG. 8(b) expands from the negative side to the positive side in the z-axis direction. As shown in FIGS. 8(a) and 8(b), the distribution of the magnetic flux generated between the coupling coil 53 of the IC module 50 and the edge of the opening 20 changes depending on the inclination direction and the magnitude of the angle of the tapered shape 45B. Therefore, by adopting the tapered shapes 45A, 45B, the magnetic coupling between the coupling coil 53 and the edge of the opening 20 can be adjusted.

[0051] In the above embodiment, the structure in which the conductor pattern 14 is provided only on one main surface of the substrate 13 has been illustrated. However, the structure of the antenna device 1 is not limited to this structure.

[0052] 9(a), the base material 13 may be omitted. In this case, the conductor pattern 14 is supported only by the resin layer 16.

[0053] 9(b), the conductor pattern 14 may have a first mesh pattern 14A provided on the first main surface 13a of the substrate 13 and a second mesh pattern 14B provided on the second main surface 13b of the substrate 13. When viewed from the thickness direction of the substrate 13, at least a part of the conductive wire of the first mesh pattern 14A may overlap with the conductive wire of the second mesh pattern 14B. In this case, since two mesh patterns 14A and 14B can be overlapped on one substrate 13, the number of substrates 13 when stacked can be reduced, costs can be reduced, and a thinner substrate can be achieved. In addition, by overlapping the mesh patterns 14A and 14B, moire can be suppressed and the loop current can be increased, thereby improving communication characteristics.

[0054] Also, as shown in FIG. 9(c) and FIG. 10(a)(b), a plurality of layers of conductor patterns 14 may be laminated. In this case, the communication characteristics can be improved by increasing the loop current. As shown in FIG. 9(c), a structure in which the conductor pattern 14 is provided on one side of the substrate 13 may be laminated in multiple layers. Also, as shown in FIG. 10(a), a structure in which the conductor pattern 14 is provided on one side of the substrate 13 and a structure in which the conductor pattern 14 (mesh patterns 14A, 14B) are provided on both sides of the substrate 13 may be laminated in multiple layers. Also, as shown in FIG. 10(b), a structure in which the conductor pattern 14 (mesh patterns 14A, 14B) are provided on both sides of the substrate 13 may be laminated in multiple layers.

[0055] [Form 1] An antenna device including a mesh-shaped conductor pattern having a plurality of mesh portions, the conductor pattern includes a plurality of first conductive lines extending in a first direction and a plurality of second conductive lines extending in a second direction intersecting the first direction; an opening and a slit extending from the opening to an edge of the conductor pattern are formed in the conductor pattern as a region in which the first conductive line and the second conductive line are not formed; The width of the slit is smaller than the width of the opening, An antenna device, wherein at least a portion of the mesh portion arranged on the edge of the slit is open to the slit. [Form 2] 2. The antenna device according to claim 1, wherein the mesh portion arranged on the edge of the opening is open to the opening. [Form 3] The antenna device of embodiment 1, wherein a conductor portion having a line width wider than the first conductive line and the second conductive line is arranged along an edge of the opening. [Form 4] Further comprising a substrate, the conductor pattern has a first mesh pattern provided on a first main surface of the base material and a second mesh pattern provided on a second main surface of the base material, 4. The antenna device of any one of embodiments 1 to 3, wherein at least a portion of the conductive wires of the first mesh pattern overlaps with the conductive wires of the second mesh pattern when viewed in a thickness direction of the base. [Form 5] 5. The antenna device according to any one of the first to fourth aspects, wherein a plurality of layers of the conductor patterns are laminated. [Form 6] The antenna device of claim 2, wherein a pair of first ends of the first conductive wires facing each other in the first direction through the opening, and a pair of second ends of the second conductive wires facing each other in the second direction through the opening, have a tapered shape expanding from one side to the other in the thickness direction. [Form 7] 7. The antenna device of any one of embodiments 1 to 6, wherein the first conductive wire and the second conductive wire have a line thickness greater than a line width. [Form 8] The antenna device according to any one of the first to seventh embodiments, wherein the mesh portion is provided with a resin, and a space is formed in the opening portion. [Form 9] The antenna device according to any one of the first to 8 embodiments, wherein one of the first conductive wire and the second conductive wire is approximately parallel to the extension direction of the slit, and the other is approximately perpendicular to the extension direction. [Form 10] 10. The antenna device according to any one of the first to ninth embodiments, wherein a width of the slit is larger than a pitch of the mesh portion. [Form 11] An antenna device according to any one of aspects 1 to 10; and an IC module disposed in the opening. [Explanation of symbols]

[0056] 1...antenna device, 13...substrate, 14...conductor pattern, 14A...first mesh pattern, 14B...second mesh pattern, 16...resin layer (resin), 17...mesh portion, 20...opening, 21...slit, 30...first conductive wire, 31...second conductive wire, 50...IC module, 100...IC card.

Claims

1. An antenna device including a mesh-shaped conductor pattern having a plurality of mesh portions, the conductor pattern includes a plurality of first conductive lines extending in a first direction and a plurality of second conductive lines extending in a second direction intersecting the first direction; the conductor pattern has an opening and a slit extending from the opening to an edge of the conductor pattern as a region in which the first conductive line and the second conductive line are not formed, The width of the slit is smaller than the width of the opening, An antenna device, wherein at least a portion of the mesh portion arranged on the edge of the slit is open to the slit.

2. The antenna device according to claim 1 , wherein the mesh portion disposed on an edge of the opening is open toward the opening.

3. The antenna device according to claim 1 , wherein a conductor portion having a line width wider than the first conductive line and the second conductive line is disposed along an edge of the opening.

4. Further comprising a substrate, the conductor pattern has a first mesh pattern provided on a first main surface of the base material and a second mesh pattern provided on a second main surface of the base material, The antenna device according to claim 1 , wherein at least a portion of the conductive lines of the first mesh pattern overlaps with a conductive line of the second mesh pattern when viewed in a thickness direction of the base material.

5. The antenna device according to claim 1 , wherein a plurality of layers of the conductor patterns are stacked.

6. 3. The antenna device according to claim 2, wherein a pair of first ends of the first conductive wires facing each other in the first direction through the opening and a pair of second ends of the second conductive wires facing each other in the second direction through the opening have a tapered shape expanding from one side to the other in a thickness direction.

7. The antenna device according to claim 1 , wherein the first conductive line and the second conductive line have a line thickness greater than a line width.

8. The antenna device according to claim 1 , wherein the mesh portion is provided with a resin, and a space is formed in the opening.

9. The antenna device according to claim 1 , wherein one of the first conductive line and the second conductive line is substantially parallel to a direction in which the slit extends, and the other is substantially perpendicular to the direction in which the slit extends.

10. The antenna device according to claim 1 , wherein a width of the slit is greater than a pitch of the mesh portion.

11. An antenna device according to any one of claims 1 to 10, an IC module disposed in the opening.

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