Contactless data receiver / transmitter

Abstract

This invention provides a contactless data transmitter / receiver that facilitates impedance matching. [Solution] The non-contact data transmitter / receiver 100 comprises a base material 10, an IC chip 20 provided on the base material 10, a first antenna 30, and a second antenna 40 electromagnetically coupled to the first antenna 30. The first antenna 30 has loop-shaped impedance adjustment sections 33, 34 electrically connected to the IC chip 20, and two main line sections 31, 32 extending away from each other. The second antenna 40 has a concave notch 44 that, in a plan view, includes at least a portion of the impedance adjustment sections 33, 34. The second antenna 40 is formed of mesh-like conductive wires. The wire width of the conductive wires is 0.25 μm or more and 200 μm or less.

Description

Technical Field

[0001] The present invention relates to a non-contact data transmitter.

Background Art

[0002] For example, for the purpose of efficiently performing distribution management, history management, article management, etc., a non-contact data transmitter is used. The non-contact data transmitter includes, for example, a base material, an IC chip provided on the base material, a first antenna connected to the IC chip, and a second antenna that is non-contact with the first antenna (see, for example, Patent Document 1). In the non-contact data transmitter described in Patent Document 1, the second antenna is formed of a mesh-like member made of conductive fibers or the like.

Prior Art Documents

Patent Documents

[0003]

Patent Document 1

Summary of the Invention

Problems to be Solved by the Invention

[0004] In the non-contact data transmitter, since the second antenna is formed in a mesh shape, the electrical resistance is high. Therefore, it is difficult for current to flow at the end of the second antenna. Therefore, when an IC chip is directly mounted on the second antenna, the communication distance may be shortened. In the non-contact data transmitter, a mesh antenna is used as the second antenna, and a structure that enables communication even when using a high-resistance mesh antenna is achieved by magnetically coupling the first antenna including the IC mounting portion. However, in the configuration described in Patent Document 1, impedance matching between the IC chip and the antenna may become difficult.

[0005] One aspect of the present invention aims to provide a non-contact data transmitter / receiver equipped with a mesh antenna that facilitates impedance matching. [Means for solving the problem]

[0006] One aspect of the present invention provides a non-contact data transmitter / receiver comprising a substrate, an IC chip provided on the substrate, a loop-shaped impedance adjustment section electrically connected to the IC chip, a first antenna having two main wire sections extending in directions away from each other, and a second antenna electromagnetically coupled to the main wire sections, wherein the second antenna has a concave notch that encompasses at least a portion of the impedance adjustment section in a plan view, and the second antenna is formed of a mesh-like conductive wire, the wire width of the conductive wire being 0.25 μm or more and 200 μm or less. Preferably, the notch encloses the entire impedance adjustment section in a plan view.

[0007] Preferably, the second antenna is formed so as not to overlap with the impedance adjustment unit. [Effects of the Invention]

[0008] According to one aspect of the present invention, impedance matching can be easily achieved in a non-contact data transmitter / receiver equipped with a mesh antenna. [Brief explanation of the drawing]

[0009] [Figure 1] This is a schematic plan view showing a contactless data transmitter / receiver according to the first embodiment. [Figure 2] This is a schematic cross-sectional view showing a contactless data transmitter / receiver according to the first embodiment. [Figure 3] This is a schematic cross-sectional view showing a contactless data transmitter / receiver according to the first embodiment. [Figure 4] This is a plan view of a part of the first antenna of a non-contact type data transmitter / receiver according to the first embodiment. [Figure 5]This is a schematic plan view showing the substrate and the second antenna. [Figure 6] This is a plan view of a part of the second antenna of a non-contact type data transmitter / receiver according to the first embodiment. [Figure 7] This figure shows the results of the frequency response evaluation test. [Figure 8] This is a schematic cross-sectional view showing a contactless data transmitter / receiver according to the second embodiment. [Figure 9] This is a partial plan view of a modified version of the second antenna. [Figure 10] This is a schematic plan view showing a contactless data transmitter / receiver according to the third embodiment. [Figure 11] This is a partial plan view of a modified version of the first antenna. [Figure 12] This is a schematic cross-sectional view showing another example of a contactless data transmitter / receiver according to the first embodiment. [Modes for carrying out the invention]

[0010] The contactless data transmitter / receiver of the embodiment will be described in detail below with reference to the drawings.

[0011] [Contactless data receiver / transmitter] (First embodiment) Figure 1 is a schematic plan view showing a non-contact data transmitter / receiver 100 according to the first embodiment. Figures 2 and 3 are schematic cross-sectional views showing the non-contact data transmitter / receiver 100. Figure 2 shows the II cross-section of Figure 1. Figure 3 shows the II-II cross-section of Figure 1. Figure 4 is a plan view of a part of the first antenna 30. Figure 5 is a schematic plan view showing the base material 10 and the second antenna 40. Figure 6 is a plan view of a part of the second antenna 40.

[0012] As shown in Figure 1, the contactless data transmitter / receiver 100 comprises a base material 10, an IC chip 20, a first antenna 30, a second antenna 40, and an insulating layer 50. The contactless data transmitter / receiver 100 is also referred to as an RFID tag or an IC tag.

[0013] The base material 10 is, for example, rectangular in a plan view. The base material 10 is in a plate shape. The base material 10 is, for example, formed of resin. Examples of the resin constituting the base material 10 include polyester resins such as polyethylene terephthalate (PET), polyolefin resins, polyfluoroethylene-based resins, polyamide resins, vinyl polymers, acrylic resins, polystyrene, polycarbonate, and the like.

[0014] The base material 10 is, for example, transparent. The base material 10 may have a visible light transmittance of 50% or more in the entire wavelength range of visible light (wavelength 380 nm to 780 nm) in the thickness direction (Z direction). A visible light transmittance of 70% or more is preferable. The visible light transmittance can be measured in accordance with JIS K7361-1:1997. When the base material 10 is transparent, the design property of the non-contact type data transmitter 100 can be enhanced.

[0015] The longitudinal direction (the left-right direction in FIG. 1) of the first main surface 10a, which is one surface of the base material 10, is the X direction. One direction in the X direction (the right side in FIG. 1) is the +X side. The direction opposite to the +X side is the -X side. The short-side direction (the up-down direction in FIG. 1) of the first main surface 10a of the base material 10 is the Y direction. The Y direction is orthogonal to the X direction. One direction in the Y direction (the upper side in FIG. 1) is the +Y side. The direction opposite to the +Y side is the -Y side.

[0016] The Z direction is orthogonal to the X direction and the Y direction. One direction in the Z direction is the +Z side. The direction opposite to the +Z side is the -Z side. Looking from the Z direction is referred to as a plan view. The first main surface 10a of the base material 10 is the surface on the +Z side.

[0017] The first antenna 30 has two main line parts 31, 32, two impedance adjustment parts 33, 34, and a base part 35. The main line parts 31, 32, the impedance adjustment parts 33, 34, and the base part 35 are, for example, integrally formed. As shown in FIGS. 2 and 3, the first antenna 30 is formed on the first main surface 10a of the base material 10.

[0018] As shown in Figure 1, the two main line portions 31 and 32 extend from the base portion 35 in directions away from each other along the longitudinal direction (X direction) of the base material 10. Of the main line portions 31 and 32, the first main line portion 31 is formed in a straight line extending from the base portion 35 toward the +X side. Of the main line portions 31 and 32, the second main line portion 32 is formed in a straight line extending from the base portion 35 toward the -X side. The first main line portion 31 and the second main line portion 32 are located symmetrically with respect to the center of the longitudinal direction of the base material 10. The line width of the main line portions 31 and 32 may be, for example, 0.1 mm or more and 1 mm or less.

[0019] As shown in Figure 4, of the impedance adjustment units 33 and 34, the first impedance adjustment unit 33 includes an outward extension 51, a lateral extension 53, and an inward extension 55. The second impedance adjustment unit 34 includes an outward extension 52, a lateral extension 54, and an inward extension 56.

[0020] The first impedance adjustment section 33 and the second impedance adjustment section 34 are located symmetrically with respect to the longitudinal center of the base material 10. The two impedance adjustment sections 33 and 34 each have a folded shape that is convex outward.

[0021] The impedance adjustment sections 33 and 34 are located at different positions in the Y direction relative to the main lines 31 and 32. More specifically, when viewed from the X direction, the impedance adjustment sections 33 and 34 are formed on the -Y side relative to the main lines 31 and 32.

[0022] The base ends of the outward extensions 51 and 52 are connected to the main lines 31 and 32 via the base 35. The two outward extensions 51 and 52 extend away from each other along the longitudinal direction (X direction) of the base material 10 from the base 35. Specifically, the outward extension 51 of the first impedance adjustment section 33 extends to the +X side. The outward extension 52 of the second impedance adjustment section 34 extends to the -X side.

[0023] The lateral extension 53 extends from the tip of the outward extension 51 (the end opposite to the base end) in the width direction (-Y side) of the base material 10. The lateral extension 54 extends from the tip of the outward extension 52 (the end opposite to the base end) in the width direction (-Y side) of the base material 10. The lateral extension 53 connects the tip (outer end) of the outward extension 51 to the base end (outer end) of the inward extension 55. The lateral extension 54 connects the tip (outer end) of the outward extension 52 to the base end (outer end) of the inward extension 56. The lateral extensions 53 and 54 may have a curved shape that is convex in the direction away from each other.

[0024] The two inward extensions 55 and 56 extend from the tips (-Y side ends) of the lateral extensions 53 and 54, respectively, in a direction that moves them toward each other along the longitudinal direction (X direction) of the base material 10. Specifically, the inward extension 55 of the first impedance adjustment section 33 extends toward the -X side. The inward extension 56 of the second impedance adjustment section 34 extends toward the +X side. The tips of the two inward extensions 55 and 56 face each other.

[0025] The impedance adjustment sections 33 and 34 each extend outward from the base 35, then fold back and extend inward to reach the IC chip 20. Therefore, the impedance adjustment sections 33 and 34 are formed in a loop shape as a whole. The impedance adjustment sections 33 and 34 match the impedance between the IC chip 20 and the first antenna 30.

[0026] The impedance adjustment sections 33 and 34 are formed by combining two impedance adjustment sections 33 and 34, each with an outwardly convex folded shape, and are therefore ring-shaped overall. In this embodiment, the impedance adjustment sections 33 and 34 are oval-ring or rectangular-ring shaped with their longitudinal direction aligned with the X direction.

[0027] As shown in Figure 1, the length L1 (dimension in the X direction) of the impedance adjustment sections 33 and 34 may be less than or equal to the distance L2 between the first section 41 and the second section 42. The length L1 of the impedance adjustment sections 33 and 34 may also be less than the distance L2 between the first section 41 and the second section 42.

[0028] It is desirable that the impedance adjustment sections 33 and 34 be located between the first section 41 and the second section 42 when viewed from the Y direction. More specifically, the impedance adjustment sections 33 and 34 are located -X side of the first section 41 when viewed from the Y direction. The impedance adjustment sections 33 and 34 are located +X side of the second section 42 when viewed from the Y direction.

[0029] It is desirable that at least a portion of the impedance adjustment sections 33 and 34 be located between the first section 41 and the second section 42 in a plan view. In this embodiment, a portion of the impedance adjustment sections 33 and 34 is located between the first section 41 and the second section 42 in a plan view. The entire impedance adjustment section 33 and 34 may be located between the first section 41 and the second section 42.

[0030] At least a portion of the impedance adjustment sections 33 and 34 is enclosed in the notch 44 of the second antenna 40 in a plan view. In this embodiment, a portion of the impedance adjustment sections 33 and 34 is enclosed in the notch 44 in a plan view. The impedance adjustment sections 33 and 34 may be entirely enclosed in the notch 44.

[0031] It is desirable that the impedance adjustment sections 33 and 34 are formed so as not to overlap with the second antenna 40. This enhances the magnetic field coupling effect between the first antenna 30 and the second antenna 40, thereby increasing the communication distance.

[0032] In the non-contact data transmitter / receiver 100, the communication characteristics can be adjusted by setting the shape, dimensions, and other settings of the impedance adjustment units 33 and 34. For example, the resonant frequency changes depending on the X-direction dimension of the impedance adjustment units 33 and 34. Therefore, the frequency characteristics of the non-contact data transmitter / receiver 100 can be determined by setting the X-direction dimension of the impedance adjustment units 33 and 34.

[0033] The first antenna 30 may be a metal layer (conductive layer) formed of a metal such as aluminum or copper. The metal layer may be formed of a metal foil, a thin metal film formed by plating, a thin metal film formed by metal vapor deposition, a metal plate, etc. The first antenna 30 may be formed into a predetermined shape by etching the metal layer, for example. The first antenna 30 may also be formed of a conductive ink such as a polymer-type conductive ink or a silver ink composition.

[0034] The IC chip 20 is not particularly limited and can be any chip that allows information to be written to and read via the antennas 30 and 40 in a contactless manner. Examples of IC chips 20 include contactless IC tags, contactless IC labels, and contactless IC cards. The IC chip 20 is mounted on the first main surface 10a of the substrate 10.

[0035] The IC chip 20 is installed across the inward extension portion 55 and the inward extension portion 56. The IC chip 20 is electrically connected to the inward extension portions 55 and 56.

[0036] As shown in Figures 2 and 3, the insulating layer 50 is formed on the first main surface 10a of the substrate 10. The insulating layer 50 covers the first antenna 30. The insulating layer 50 is made of, for example, a resin. Examples of resins that make up the insulating layer 50 include polyester resins such as polyethylene terephthalate (PET), polyolefin resins, polyfluoroethylene resins, polyamide resins, vinyl polymers, acrylic resins, polystyrene, and polycarbonate.

[0037] The insulating layer 50 is, for example, transparent. The insulating layer 50 may have a visible light transmittance of 50% or more in the thickness direction (Z direction) across the entire wavelength range of visible light (wavelength 380 nm to 780 nm). A visible light transmittance of 70% or more is preferable. If the insulating layer 50 is transparent, the design of the non-contact data transmitter / receiver 100 can be enhanced. For example, if the base material 10 and the insulating layer 50 are transparent, it becomes easier to see behind the non-contact data transmitter / receiver 100. In other words, the optical transmittance (i.e., transparency) of the non-contact data transmitter / receiver 100 can be enhanced.

[0038] As shown in Figure 2, the second antenna 40 is formed on the surface 50a (the +Z side) of the insulating layer 50. As shown in Figure 5, the second antenna 40 has a rectangular shape with a concave notch 44 in a plan view. More specifically, the second antenna 40 has a rectangular notch 44 formed on one of the two long sides of the rectangle.

[0039] The second antenna 40 has a first portion 41, a second portion 42, and an intermediate portion 43. The shape (outline) of the first portion 41 and the second portion 42 in plan view is rectangular. The shape of the first portion 41 and the second portion 42 in plan view may be a rectangle having two sides along the X direction and two sides along the Y direction. For example, the shape of the first portion 41 and the second portion 42 in plan view may be a rectangle with a longer side along the X direction. The first portion 41 and the second portion 42 may be identical in shape.

[0040] The first portion 41 is positioned to overlap a portion of the first main line portion 31 in a plan view. The first portion 41 includes the portion of the first main line portion 31 that includes the tip in a plan view. The first portion 41 is electromagnetically coupled to the first main line portion 31. The first portion 41 is not in contact with the first main line portion 31 because it is separated from the first main line portion 31 by the insulating layer 50.

[0041] The second portion 42 is positioned to overlap a portion of the second main line portion 32 in a plan view. The second portion 42 includes the portion of the second main line portion 32 that includes the tip in a plan view. The second portion 42 is electromagnetically coupled to the second main line portion 32. The second portion 42 is separated from the second main line portion 32 by the insulating layer 50 and therefore does not come into contact with the second main line portion 32.

[0042] The first part 41 and the second part 42 are formed with an interval between them in the X direction. The first part 41 and the second part 42 are positioned symmetrically with respect to the longitudinal center of the base material 10. The -X side edge 41a of the first part 41 and the +X side edge 42a of the second part 42 face each other.

[0043] The intermediate portion 43 is interposed between the first portion 41 and the second portion 42. The intermediate portion 43 connects the first portion 41 and the second portion 42. The intermediate portion 43 is formed in a strip shape extending in the X direction. The intermediate portion 43 is integrally formed with respect to the first portion 41 and the second portion 42. The width of the intermediate portion 43 (dimension in the Y direction) is smaller than the width of the first portion 41 and the second portion 42 (dimension in the Y direction). The intermediate portion 43 is formed by connecting a part of the edge 41a of the first portion 41 (the +Y side portion of the edge 41a) and a part of the edge 42a of the second portion 42 (the +Y side portion of the edge 42a).

[0044] The -Y-side edge 43a of the intermediate portion 43 is located on the +Y side when viewed from the X direction, compared to the -Y-side edge of the first portion 41 and the second portion 42. Therefore, a concave notch 44 is formed on the -Y-side edge of the second antenna 40, having end edges 41a, 42a and a side edge 43a. The notch 44 is rectangular in shape because it has end edges 41a, 42a along the Y direction and a side edge 43a along the X direction. The +Y-side edge of the intermediate portion 43 is located in a position that overlaps with the +Y-side edge of the first portion 41 and the second portion 42 when viewed from the X direction. The second antenna 40 has a rectangular notch 44 formed on one of the two long sides of the rectangle (the long side on the -Y side).

[0045] Figure 6 shows a subregion A of Figure 1. As shown in Figure 6, the second antenna 40 is formed of a mesh of conductive wires. The mesh shape is, for example, a shape in which multiple conductive wires 45, 46 are combined in a grid pattern (for example, a rectangular grid). More specifically, the second antenna 40 is a shape that combines multiple straight first conductive wires 45 and multiple straight second conductive wires 46. The multiple first conductive wires 45 are arranged in parallel with spacing between them. The multiple second conductive wires 46 are arranged in parallel with spacing between them. The first conductive wires 45 and the second conductive wires 46 are orthogonal to each other. The second antenna 40 does not necessarily have conductive wires along its periphery.

[0046] The conductive wires 45 and 46 are formed of a conductive material. The conductive material includes, for example, metal-containing particles. The metal contained in the metal-containing particles is, for example, at least one selected from the group consisting of copper, silver, aluminum, and gold. In addition to the metal (conductive component), the conductive material may also contain a non-conductive component. Examples of non-conductive components include metal oxides, metal compounds, organic compounds, etc. An example of a conductive material is a conductive ink.

[0047] The wire widths of the conductive wires 45 and 46 are, for example, 0.25 μm or more (for example, 1 μm or more). Setting the wire widths of the conductive wires 45 and 46 within this range can improve the conductivity of the second antenna 40. The wire widths of the conductive wires 45 and 46 are, for example, 200 μm or less (for example, 50 μm or less). Setting the wire widths of the conductive wires 45 and 46 within this range makes it easier to see behind the second antenna 40. That is, the optical transmittance (i.e., transparency) of the second antenna 40 can be improved. The wire widths of the conductive wires 45 and 46 may be the average value of the wire widths of the conductive wires 45 and 46.

[0048] The thickness of the conductive wires 45 and 46 may be, for example, 10 nm or more (for example, 50 nm or more). Setting the thickness of the conductive wires 45 and 46 within this range can improve the conductivity of the second antenna 40. The thickness of the conductive wires 45 and 46 may be, for example, 1000 nm or less (for example, 500 nm or less). Setting the thickness of the conductive wires 45 and 46 within this range can improve the optical transmittance (i.e., transparency) of the second antenna 40. The thickness of the conductive wires 45 and 46 may be the average value of the thicknesses of the conductive wires 45 and 46.

[0049] The pitch of the conductive wires 45 and 46 may be, for example, 5 μm or more (for example, 50 μm or more). Setting the pitch of the conductive wires 45 and 46 within this range can improve the optical transmittance (i.e., transparency) of the second antenna 40. The pitch of the conductive wires 45 and 46 may be, for example, 1000 μm or less (for example, 500 μm or less). Setting the pitch of the conductive wires 45 and 46 within this range can improve the conductivity of the second antenna 40. The pitch of the conductive wires 45 and 46 may be the average value of the pitches of the conductive wires 45 and 46.

[0050] The aperture ratio of the conductive wires 45 and 46 may be, for example, 60% or more. An aperture ratio of 70% or more is preferable. An aperture ratio of 80% or more is even more preferable. An aperture ratio of 90% or more is particularly preferable. Setting the aperture ratio of the conductive wires 45 and 46 within this range can improve the optical transmittance (i.e., transparency) of the second antenna 40. The aperture ratio of the conductive wires 45 and 46 may be, for example, less than 100% (for example, 95% or less). An aperture ratio of 90% or less is also acceptable. An aperture ratio of 80% or less is also acceptable. Setting the aperture ratio of the conductive wires 45 and 46 within this range can improve the conductivity of the second antenna 40. The aperture ratio of the conductive wires 45 and 46 can be calculated from the area S1 of the region on the base material 10 where the second antenna is formed and the area S2 of the conductive wires 45 and 46 using the following formula: Aperture ratio = (1 - S2 / S1) × 100.

[0051] To form the second antenna 40, for example, the following method can be used: A conductive wire is formed on the surface 50a of the insulating layer 50 using a conductive material containing metal particles (for example, conductive ink). The conductive wire is formed, for example, by printing. The conductive wire may also be formed by coating it on the surface 50a of the insulating layer 50 by other methods. The conductive wire is heated and fired using a firing furnace or the like. It is desirable to fire the conductive wire in a non-oxidizing atmosphere. In this way, the second antenna 40 can be formed.

[0052] (Example 1) The following frequency characteristics evaluation test was performed. A non-contact data transmitter / receiver 100, as shown in Figure 1, was fabricated. The first antenna 30 was made of copper foil. The total length of the main wires 31 and 32 was 55 mm. The wire width of the main wires 31 and 32 was 0.5 mm. The length L1 (dimension in the X direction) of the impedance adjustment sections 33 and 34 was 15 mm. The dimension in the Y direction of the impedance adjustment sections 33 and 34 was 5 mm.

[0053] The second antenna 40 was formed using conductive ink. The Y-direction dimension of the second antenna 40 was 10 mm. The Y-direction dimension of the intermediate portion 43 was 5 mm. The distance L2 (X-direction distance) between the first portion 41 and the second portion 42 was 15 mm. The length of the second antenna 40 (dimension in the X direction) was set to 80 mm (test 1-1) and 70 mm (test 1-2).

[0054] (Comparative Example 1) A non-contact data transmitter / receiver similar to that in Example 1 was fabricated, except that the second antenna was made of aluminum foil (non-mesh structure), and its frequency characteristics were investigated. The length of the second antenna (dimension in the X direction) was set to 80 mm (Test 2-1) and 70 mm (Test 2-2).

[0055] (Comparative Example 2) A non-contact data transmitter / receiver similar to that in Example 1 was fabricated, except that a second antenna was not formed, and its frequency characteristics were investigated (Test 3).

[0056] Figure 7 shows the results of a frequency response evaluation test. The horizontal axis in Figure 7 represents frequency, and the vertical axis represents communication distance. As shown in Figure 7, in Comparative Example 1, which has a second antenna with a non-mesh structure, when the length of the second antenna was 70 mm (Test 2-2), the communication distance at a frequency of 920 MHz decreased by approximately 35% compared to when the length of the second antenna was 80 mm (Test 2-1).

[0057] In contrast, in Embodiment 1, which has a mesh-structured second antenna 40, when the length of the second antenna 40 was 70 mm (Test 1-2), the decrease in the communication distance at a frequency of 920 MHz was only about 15% compared to when the length of the second antenna 40 was 80 mm (Test 1-1).

[0058] These results show that when a mesh-structured second antenna 40 is used, the reduction in the communication range due to shortening the second antenna 40 can be kept to a minimum. Thus, the contactless data transmitter / receiver of Example 1 can suppress the reduction in the communication range even when size constraints are present.

[0059] [Effects of the contactless data transmitter / receiver according to this embodiment] The non-contact data transmitter / receiver 100 according to this embodiment includes a second antenna 40 that overlaps with at least a portion of the main line sections 31 and 32 in a plan view. The first antenna 30 has impedance adjustment sections 33 and 34, separate from the main line sections 31 and 32 that are electromagnetically coupled with the second antenna 40. In the non-contact data transmitter / receiver 100, there are fewer constraints on the shape, size, etc., of the impedance adjustment sections 33 and 34. Therefore, impedance matching is easily achieved.

[0060] In the non-contact data transmitter / receiver 100, the second antenna 40 has a notch 44 that encompasses at least a portion of the impedance adjustment units 33 and 34. Therefore, the frequency characteristics can be improved. In this embodiment, the notch 44 encompasses the entirety of the impedance adjustment units 33 and 34. Therefore, the frequency characteristics can be further improved.

[0061] The contactless data transmitter / receiver 100 has a second antenna 40 with a mesh structure, which helps to prevent the communication range from being shortened due to the dimensions of the second antenna 40.

[0062] Contactless data transmitters may be subject to size constraints depending on the object they are installed on. For example, if the object to be installed is small, miniaturization of the contactless data transmitter is required. In the contactless data transmitter 100 according to this embodiment, even if the length is reduced, the communication range can be kept from being shortened. Therefore, the contactless data transmitter 100 can be applied to a variety of applications.

[0063] In the non-contact data transmitter / receiver 100, the second antenna 40 is formed so as not to overlap with the impedance adjustment units 33 and 34 in a plan view. Therefore, the frequency characteristics can be improved.

[0064] [Contactless data receiver / transmitter] (Second embodiment) Figure 8 is a schematic plan view showing a contactless data transmitter / receiver 200 according to the second embodiment. Common components with other embodiments are denoted by the same reference numerals and their descriptions are omitted.

[0065] As shown in Figure 8, the contactless data transmitter / receiver 200 differs from the contactless data transmitter / receiver 100 (see Figure 3) in that an adhesive layer 60 is formed on the second main surface 10b, which is the surface opposite to the first main surface 10a of the substrate 10. The adhesive layer 60 can use an adhesive commonly used for labels.

[0066] The contactless data transmitter / receiver 200 has an adhesive layer 60 and can therefore be attached to the surface of an object. Because the contactless data transmitter / receiver 200 has an adhesive layer 60, it is a contactless data transmitter / receiver label. A contactless data transmitter / receiver label is also referred to as an RFID label or an IC label.

[0067] The contactless data transmitter / receiver 200 provides the same effect as the contactless data transmitter / receiver 100 (see Figure 3).

[0068] [Second antenna] (variant) Figure 9 is a plan view of a modified example of the second antenna. As shown in Figure 9, the second antenna 140 is formed by a mesh of conductive wires 145. The conductive wires 145 are formed in a hexagonal grid pattern. The second antenna is not limited to a rectangular or hexagonal grid; it may also be triangular, rhombic, or diamond-shaped.

[0069] [Contactless data receiver / transmitter] (Third embodiment) Figure 10 is a schematic plan view showing a contactless data transmitter / receiver 300 according to the third embodiment. Common components with other embodiments are denoted by the same reference numerals and their descriptions are omitted. As shown in Figure 10, the non-contact data transmitter / receiver 300 differs from the non-contact data transmitter / receiver 100 (see Figure 3) in that the first antenna 130 is formed on the second main surface 10b of the substrate 10 and there is no insulating layer 50.

[0070] The contactless data transmitter / receiver 300 provides the same effect as the contactless data transmitter / receiver 100 (see Figure 3). The contactless data transmitter / receiver 300 can be made thinner because it lacks an insulating layer 50.

[0071] [First antenna] (modified version) Figure 11 is a plan view of a portion of the first antenna 230, which is a modified version of the first antenna. The same reference numerals are used for previously described components, and their explanations are omitted.

[0072] The first antenna 230 has two main line sections 31, 32 and two impedance adjustment sections 233, 234. The first impedance adjustment section 233 includes a lateral extension section 53 and an inward extension section 55. The second impedance adjustment section 234 includes a lateral extension section 54 and an inward extension section 56.

[0073] The lateral extension 53 extends from the first main line 31 toward the -Y side. The lateral extension 54 extends from the second main line 32 toward the -Y side. The inward extension 55 extends from the tip of the lateral extension 53 toward the -X side. The inward extension 56 extends from the tip of the lateral extension 54 toward the +X side. The two inward extensions 55 and 56 extend toward each other, with their tips facing each other.

[0074] The impedance adjustment sections 233 and 234 extend laterally from the main wire sections 31 and 32, respectively, and then extend inward from their tips to reach the IC chip 20. Therefore, the impedance adjustment sections 233 and 234 are formed in a loop shape as a whole.

[0075] [Contactless data receiver / transmitter] (Other examples) Figure 12 is a schematic cross-sectional view showing another example of a contactless data transmitter / receiver according to the first embodiment. As shown in Figure 12, the contactless data transmitter / receiver 100 (see Figure 2) may have an insulating layer 50 that is bonded to the first main surface 10a of the substrate 10 by an adhesive layer 70. The adhesive layer 70 is preferably transparent.

[0076] Although embodiments of the present invention have been described above, the configurations and combinations thereof in the embodiments are merely examples, and additions, omissions, substitutions, and other modifications to the configurations are possible without departing from the spirit of the present invention.

[0077] The first portion of the second antenna should be positioned so as to overlap part or all of the first main line portion in a plan view. That is, the first portion should be positioned so as to overlap at least part of the first main line portion in a plan view. The second portion of the second antenna should be positioned so as to overlap part or all of the second main line portion in a plan view. That is, the second portion should be positioned so as to overlap at least part of the second main line portion in a plan view.

[0078] The first and second parts of the second antenna are not limited to a rectangular shape; they may be polygonal, circular, elliptical, or other shapes. In the non-contact data transmitter / receiver 100 shown in Figure 1, the main lines 31 and 32 are straight, but the shape of the main lines is not particularly limited. The main lines may have a curved shape.

[0079] In the non-contact data transmitter / receiver 100 shown in Figure 1, a portion of the impedance adjustment units 33 and 34 is located within the notch 44 of the second antenna 40, but the relative position between the impedance adjustment unit and the second antenna is not particularly limited. For example, a portion of the impedance adjustment unit (including the end in the X direction) may be located in a position that overlaps with the second antenna. [Explanation of Symbols]

[0080] 10…Base material, 20…IC chip, 30, 130, 230…First antenna, 31…First main line section (main line section), 32…Second main line section (main line section), 33, 34, 233, 234…Impedance adjustment section, 40, 140…Second antenna, 44…Notch, 45, 46, 145…Conductive wire, 100, 200, 300…Contactless data receiver / transmitter

Claims

1. Substrate and An IC chip provided on the substrate, A first antenna having a loop-shaped impedance adjustment section electrically connected to the IC chip and two main wire sections extending in directions away from each other, A second antenna is electromagnetically coupled to the main line section, Equipped with, The second antenna has a concave notch that, in a plan view, includes at least a portion of the impedance adjustment section. The second antenna is formed of a mesh of conductive wires, The wire width of the conductive wire is 0.25 μm or more and 200 μm or less. Contactless data receiver / transmitter.

2. The aforementioned notch encompasses the entire impedance adjustment section in a plan view. The contactless data receiver / transmitter according to claim 1.

3. The second antenna is formed so as not to overlap with the impedance adjustment unit. The contactless data receiver / transmitter according to claim 1.

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