Antenna device, antenna unit, and impedance tuning mechanism

Abstract

To provide an antenna device capable of achieving a better antenna efficiency while reducing the size.SOLUTION: An antenna device 100 includes a carrier 3, an impedance tuning mechanism 1 disposed so as to correspond to the carrier 3, and an antenna mechanism 2 disposed on the impedance tuning mechanism 1. The impedance tuning mechanism 1 includes a grounding layer 11 disposed on the carrier 3 and an impedance tuning layer 12 spaced apart from the grounding layer 11. A projection region defined by orthogonally projecting the impedance tuning layer 12 onto the grounding layer 11 is located inside of an outer edge of the grounding layer 11. The impedance tuning layer 12 has at least one elongated gap 123 recessed from an outer contour 121 thereof to a center thereof. A thickness of the impedance tuning mechanism 1 is within a range from 0.4% to 25% of a wavelength corresponding to the center frequency, the antenna mechanism 2 being applied to the center frequency.SELECTED DRAWING: Figure 1

Description

Technical Field

[0001] The present invention relates to impedance adjustment, and particularly to an antenna device, an antenna apparatus, and an impedance adjustment mechanism. The present invention relates to.

Background Art

[0002] Existing impedance adjustment mechanisms for adjusting the impedance of an antenna are often limited to a specific structure. For example, they are adhesive antennas. Therefore, existing impedance adjustment mechanisms are not easily improved to further enhance their value. Thus, the inventor believes that the above-mentioned drawbacks can be improved, and focuses on research along with the application of scientific principles, and finally proposes the present invention which is a reasonable design and effectively improves the above-mentioned drawbacks.

Summary of the Invention

Problems to be Solved by the Invention

[0003] Embodiments of the present invention aim to provide an antenna device, an antenna apparatus, and an impedance adjustment mechanism, which can effectively improve the possible drawbacks caused by existing impedance adjustment mechanisms.

Means for Solving the Problems

[0004] Embodiments of the present invention disclose an antenna device. The antenna device includes a carrier, an impedance adjustment mechanism installed corresponding to the carrier, and an antenna mechanism. The impedance adjustment mechanism includes a ground layer installed on the carrier and an impedance adjustment layer installed at an interval from the ground layer. The projection area formed when the impedance adjustment layer is orthogonally projected onto the ground layer is located inside the outer edge of the ground layer. Here, the impedance adjustment layer forms at least one elongated gap that is recessed from its outer contour toward the center. The antenna mechanism is installed on the impedance adjustment mechanism, and the thickness of the impedance adjustment mechanism is 0.4% to 25% of the wavelength corresponding to the center frequency applied by the antenna mechanism.

[0005] Embodiments of the present invention disclose an impedance adjustment mechanism. The impedance adjustment mechanism includes a ground layer and an impedance adjustment layer installed at an interval from the ground layer. The projection area formed when the impedance adjustment layer is orthogonally projected onto the ground layer is located inside the outer edge of the ground layer. Here, the impedance adjustment layer forms at least one elongated gap that is recessed from its outer contour toward the center.

[0006] Embodiments of the present invention further disclose an antenna device. The antenna device includes an impedance adjustment mechanism installed corresponding to a carrier and an antenna mechanism. The impedance adjustment mechanism includes a ground layer installed on the carrier and an impedance adjustment layer installed at an interval from the ground layer. The projection area formed when the impedance adjustment layer is orthogonally projected onto the ground layer is located inside the outer edge of the ground layer. Here, a gap is formed in the impedance adjustment layer. The antenna mechanism is installed on the impedance adjustment mechanism, and the thickness of the impedance adjustment mechanism is 0.4% to 25% of the wavelength corresponding to the center frequency applied by the antenna mechanism.

[0007] Based on the above, the antenna device, antenna apparatus, and impedance adjustment mechanism disclosed in the embodiments of the present invention adopt a new structural design (e.g., at least one of the elongated gaps and the gaps) different from the prior art for the impedance adjustment layer. By combining the impedance adjustment layer with the ground layer, the impedance adjustment mechanism can be applied to the antenna mechanism with a smaller thickness, and at the same time, better antenna efficiency can be achieved.

[0008] To further understand the features and technical content of the invention, the following provides a detailed description of the present invention and refers to the accompanying drawings. However, the provided accompanying drawings are only for reference and explanation, and are not intended to limit the scope of the claims of the present invention.

Brief Description of the Drawings

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Embodiments for Carrying Out the Invention

[0010] Embodiments of the "antenna device, antenna apparatus, and impedance adjustment mechanism" disclosed by the present invention will be described as follows. Those skilled in the art can understand the merits and effects of the present invention based on the disclosure of this specification. The present invention can be implemented or applied by other different embodiments. Each detail in this specification can also be equally deformed and changed based on various viewpoints or applications without departing from the spirit of the present invention. Also, the drawings of the present invention are for simple and schematic explanation and do not show actual dimensions. In the following embodiments, technical matters related to the present invention will be further described, but the disclosed content does not limit the present invention. Also, the term "or" used in this specification can include any one or a combination of multiple related listed items according to the actual situation.

[0011] Throughout this specification, terms such as "first", "second", "third", etc. may be used to describe various components and signals, but it should be understood that these components and signals should not be limited by these terms. These terms are mainly used to distinguish one component from another or one signal from another. Furthermore, the term "or" used in this specification can appropriately include any one or a combination of the related listed items.

[0012] [First Embodiment] Refer to the first embodiment of the present invention shown in FIGS. 1 to 9. As shown in FIGS. 1 to 3, this embodiment discloses an antenna device 100, preferably including a carrier 3, an antenna mechanism 2 arranged at an interval from the carrier 3, an impedance adjustment mechanism 1 arranged between the carrier 3 and the antenna mechanism 2, a box body 4 for accommodating the above-mentioned plurality of components, and a reader 5 installed on the box body 4, but the present invention is not limited thereto.

[0013] For example, in other embodiments of the present invention, although not shown in the figures, the antenna device 100 can omit at least one of the box body 4 and the reader 5 based on design requirements. Also, the impedance adjustment mechanism 1 and the antenna mechanism 2 can be integrated and referred to as an antenna device 10, which can be applied (e.g., sold) alone or used in combination with other components. Furthermore, the impedance adjustment mechanism 1 can also be applied (e.g., sold) alone or used in combination with other components.

[0014] In this embodiment, the carrier 3 is flat and sheet-shaped and can be a high-loss dielectric. For example, it can be a wave absorber, a wafer, or a metal sheet, but the present invention is not limited thereto. The box body 4 forms a plurality of storage spaces 41, and the carrier 3, the impedance adjustment mechanism 1, and the antenna mechanism 2 are all arranged together in one of the storage spaces 41 in the box body 4. And the reader 5 can read the signal output from the antenna mechanism 2, thereby measuring the specific position of the carrier 3 in the box body 4. Further explained, the antenna device 100 is described as an example applied to the semiconductor region in this embodiment. The box body 4 is, for example, a wafer box (front opening unified pod, FOUP), and the carrier 3 is, for example, a wafer, but the present invention is not limited thereto.

[0015] The impedance adjustment mechanism 1 is installed corresponding to the carrier 3, and the antenna mechanism 2 is installed on the impedance adjustment mechanism 1. That is, the impedance adjustment mechanism 1 is sandwiched between the carrier 3 and the antenna mechanism 2. Here, the antenna mechanism 2 is applied to a specific center frequency, and the thickness H1 of the impedance adjustment mechanism 1 is 0.4% to 25% of the wavelength corresponding to the specific center frequency.

[0016] More specifically, the impedance adjustment mechanism 1 in the present embodiment includes a ground layer 11 installed on the carrier 3, an impedance adjustment layer 12 arranged at an interval in the thickness direction H from the ground layer 11, and a dielectric layer 13 sandwiched between the ground layer 11 and the impedance adjustment layer 12. Here, the resonant frequency of the impedance adjustment layer 12 can be adjusted according to its size (e.g., curves L1, L2, L3 shown in FIG. 4), and a preferable arrangement of the size of the impedance adjustment layer 12 is that the layout distance R between the outer contour 121 of the impedance adjustment layer 12 and its center C is 25% to 45% of the wavelength, but the present invention is not limited thereto.

[0017] Furthermore, the impedance adjustment layer 12 is preferably located directly above the ground layer 11. Thereby, the ground layer 11 can shield the side surface of the impedance adjustment layer 12. That is, the projection area formed by the impedance adjustment layer 12 projecting onto the ground layer 11 is located inside the outer edge of the ground layer 11.

[0018] Furthermore, the insulator layer 13 is formed of an insulating material, and its relative permittivity is preferably between 1 and 6, but can be adjusted and changed according to design requirements, and the present invention is not limited thereto. For example, in other embodiments not depicted in the present invention, it is also possible to omit the insulator layer 13 from the impedance adjustment mechanism 1 (that is, the insulator layer 13 is substantially equivalent to an air dielectric layer).

[0019] The antenna mechanism 2 includes an electronic component 21 (e.g., a detection chip) installed in the impedance adjustment mechanism 1, a detection antenna 22 electrically coupled to the electronic component 21, and an insulator layer 23 installed on the impedance adjustment layer 12 and supporting the detection antenna 22 (i.e., the insulator layer 23 separates the impedance adjustment layer 12 from the detection antenna 22).

[0020] In this embodiment, the impedance adjustment layer 12 has an opening 122 for installing the electronic component 21 therein, and the insulator layer 13 forms a housing hole 131 communicating with the opening 122. Thereby, the electronic component 21 is arranged through the opening 122 and the housing hole 131 and installed on the ground layer 11.

[0021] More specifically, the opening 122 is preferably formed at the center C of the impedance adjustment layer 12. And the area of the opening 122 is preferably 10% or less of the area surrounded by the outer contour 121 of the impedance adjustment layer 12. The housing hole 131 is smaller than the opening 122 and exposes a part of the ground layer 11 so that the electronic component 21 can be placed thereon, but the present invention is not limited thereto. For example, in other embodiments not depicted in the present invention, the opening 122 can also be arranged at a position away from the center C of the impedance adjustment layer 12. Or, the housing hole 131 does not completely penetrate the insulator layer 13, and its depth can be adjusted according to the design requirements. Alternatively, there may be a case where the impedance adjustment layer 12 does not form the opening 122, the insulator layer 13 does not form the housing hole 131, and the electronic component 21 is directly arranged on the impedance adjustment layer 12.

[0022] Furthermore, for the detection antenna 22, the antenna projection area formed by orthographically projecting onto the top surface of the impedance adjustment layer 12 is completely located above the top surface and does not cover any gaps. That is, it is preferable that no gap is formed in the portion of the impedance adjustment layer 12 corresponding to the detection antenna 22, but the present invention is not limited thereto.

[0023] The above is the description of the compatibility between the impedance adjustment mechanism 1 and the antenna mechanism 2. To enable the impedance adjustment mechanism 1 to have better operating performance, the structure of the impedance adjustment layer 12 can be designed according to actual requirements. Hereinafter, some preferred examples will be selected and described from various possible structural designs of the impedance adjustment layer 12 (for example, FIGS. 5 to 9), but the present invention is not limited thereto.

[0024] Furthermore, it should be noted that the outer contour 121 of the impedance adjustment layer 12 in the present embodiment is circular. However, in other embodiments not depicted in the present invention, the outer contour 121 of the impedance adjustment layer 12 can be adjusted and changed according to design requirements (for example: polygon).

[0025] As shown in FIGS. 3 and 5, the impedance adjustment layer 12 forms a long gap 123 recessed from the outer contour 121 toward the center C. That is, the long gap 123 communicates with the aperture 122, and the long gap 123 is linear and penetrates through the impedance adjustment layer 12 in the thickness direction H. In other words, the impedance adjustment layer 12 in the present embodiment can form only the long gap 123 (and the aperture 122). Furthermore, the width W123 of the long gap 123 is preferably 3% or less of the wavelength. Based on this, when the impedance adjustment layer 12 as shown in FIG. 5 is used, the antenna efficiency of the antenna device 10 is approximately 0.239 or more. Here, the antenna efficiency is the gain divided by the directivity.

[0026] As shown in FIGS. 3, 6, and 7, the number of the long gaps 123 formed in the impedance adjustment layer 12 can also be N, and N is a positive integer and is preferably an even number. Here, the N long gaps 123 are preferably arranged in pairs in a straight line, whereby the impedance adjustment layer 12 is divided into N adjustment blocks S separated from each other. Further, as shown in FIG. 7, each adjustment block S has a central angle σS with respect to the center C, and the difference in the central angle σS between any two adjustment blocks S is preferably 120 degrees or less.

[0027] In other words, the impedance adjustment layer 12 can form only the N long gaps 123 (and the apertures 122). To further explain, N shown in FIG. 6 in the present embodiment is 2, and the antenna efficiency of the antenna device 10 when the impedance adjustment layer 12 shown in FIG. 6 is used is approximately 0.291 or more. Also, N shown in FIG. 7 is 4, and the antenna efficiency of the antenna device 10 when the impedance adjustment layer 12 shown in FIG. 7 is used is approximately 0.286 or more. Further, in other embodiments not depicted in the present invention, N may be an even number of 6 or more, or N may be a positive integer greater than 1 and may be an odd number.

[0028] As shown in FIGS. 3 and 8, after forming the plurality of elongated gaps 123, the impedance adjustment layer 12 can further form a plurality of inner gaps 124 from the center C toward the outer contour 121. The width of each inner gap 124 is preferably 3% or less of the wavelength. The plurality of inner gaps 124 have substantially the same length (for example, 50% to 80% of the layout distance), communicate with the apertures 122, but do not touch the outer contour 121. Each inner gap 124 linearly penetrates the thickness direction H and passes through the impedance adjustment layer 12, but is not limited thereto. For example, in other embodiments not depicted in the present invention, the lengths of the plurality of inner gaps 124 may be slightly different.

[0029] In other words, the impedance adjustment layer 12 in the present embodiment can form only the plurality of inner gaps 124 and the elongated gaps 123 (and the apertures 122). Further, in FIG. 8 of the present embodiment, the number of the inner gaps 124 formed in the impedance adjustment layer 12 is described as two. Each inner gap 124 and the elongated gap 123 preferably sandwich a first angle σ1 of 85 degrees to 165 degrees, more preferably 105 degrees to 165 degrees. Based on this, when the impedance adjustment layer 12 shown in FIG. 8 is used, the antenna efficiency of the antenna device 10 is generally 0.417 or more.

[0030] As shown in FIGS. 3 and 9, after forming the plurality of elongated gaps 123 and the plurality of inner gaps 124, the impedance adjustment layer 12 can further form a plurality of outer gaps 125 from the outer contour 121 toward the center C. And the width of each outer gap 125 is preferably 3% or less of the wavelength.

[0031] The lengths of the plurality of the outer gaps 125 are substantially the same (for example, 50% to 80% of the layout distance), do not touch the center C (that is, are not in communication with the opening 122), and each of the outer gaps 125 is linear and passes through the impedance adjustment layer 12 in the thickness direction H, but is not limited thereto. For example, in other embodiments not depicted in the present invention, the lengths of the plurality of the outer gaps 125 may be slightly different. In other words, the impedance adjustment layer 12 in the present embodiment can form only the plurality of the outer gaps 125, the plurality of the inner gaps 124, and the long gap 123 (and the opening 122).

[0032] More specifically, between any two adjacent inner gaps 124, the outer gap 125 or the long gap 123 is arranged, whereby the impedance adjustment layer 12 defines M adjustment blocks S, M is a positive integer, and the M adjustment blocks S are adjacent to each other and form an integral structure. Further, each adjustment block S has a central angle σS with respect to the center C, and the difference in the central angle σS between any two adjustment blocks S is preferably 60 degrees or less.

[0033] More specifically, in FIG. 9 of the present embodiment, the number of the inner gaps 124 formed in the impedance adjustment layer 12 is four, and the number of the outer gaps 125 formed in the impedance adjustment layer 12 is three. Among them, the two inner gaps 124 away from the long gap 123 preferably form a first angle σ1 of 85 degrees to 165 degrees, more preferably 105 degrees to 165 degrees, with the long gap 123 respectively. On the other hand, the two inner gaps 124 close to the long gap 123 preferably form a second angle σ2 of 25 degrees to 65 degrees with the long gap 123 respectively. Based on this, when the impedance adjustment layer 12 shown in FIG. 9 is used, the antenna efficiency of the antenna device 10 is substantially 0.409 or more.

[0034] As described above, as shown in FIGS. 1 to 9, in this embodiment, the antenna device 100, the antenna apparatus 10, and the impedance adjustment mechanism 1 can apply the impedance adjustment mechanism 1 to the antenna mechanism 2 with a thinner thickness (e.g., 0.4% to 25% of the wavelength) by the structural design of the impedance adjustment layer 12 (e.g., at least one of the elongated gaps 123) and its combination with the ground layer 11, and at the same time achieve better antenna efficiency (e.g., 0.239 or more).

[0035] [Second Embodiment] Please refer to FIG. 10. FIG. 10 shows the second embodiment of the present invention. Since this embodiment is similar to the above-described first embodiment, the common points of the two embodiments will not be described in detail again. However, this embodiment is mainly different from the above-described first embodiment in terms of the impedance adjustment layer 12.

[0036] In this embodiment, gaps 126 are formed in the impedance adjustment layer 12, and the width of each gap 126 is preferably 3% or less of the wavelength. The gap 126 is formed to extend from the center C of the impedance adjustment layer 12 toward the outer contour 121, and the gap 126 does not touch the outer contour 121. The gap 126 is linear and passes through the impedance adjustment layer 12 in the thickness direction H, and the length of the gap 126 exceeds 50% of the layout distance R. In other words, the impedance adjustment layer 12 in this embodiment forms only the gap 126 (and the opening 122).

[0037] [Third Embodiment] Please refer to FIGS. 11 and 12. FIGS. 11 and 12 show the third embodiment of the present invention. Since this embodiment is similar to the above-described first embodiment, the common points of the two embodiments will not be described in detail again. However, this embodiment is mainly different from the above-described first embodiment in terms of the impedance adjustment layer 12.

[0038] In this embodiment, a gap 126 is formed in the impedance adjustment layer 12, and the width of each gap 126 is preferably 3% or less of the wavelength. The gap 126 is linear and passes through the impedance adjustment layer 12 in the thickness direction H. Here, the length of the gap 126 exceeds 50% of the layout distance R. In other words, the impedance adjustment layer 12 in this embodiment can form only the gap 126.

[0039] Furthermore, the impedance adjustment layer 12 in this embodiment defines a circular layout area 127, the center of which is the center C of the impedance adjustment layer 12, and the area of the circular layout area 127 is between 15% and 25% of the area surrounded by the outer contour 121 of the impedance adjustment layer 12, but the present invention is not limited thereto. In this embodiment, the gap 126 intersects (or passes through) the circular layout area 127.

[0040] More specifically, when the above conditions are satisfied, the position of the gap 126 in the impedance adjustment layer 12 of this embodiment can be adjusted and changed according to the design requirements. For example, as shown in FIG. 11, the gap 126 is formed by extending from the outer contour 121, and the gap 126 does not pass through the center C. Alternatively, as shown in FIG. 12, the gap 126 is formed without touching the outer contour 121 (and passing through the center C).

[0041] [Technical Effects According to Embodiments of the Present Invention] Generally, the antenna device, antenna apparatus, and impedance adjustment mechanism disclosed in the embodiments of the present invention employ an impedance adjustment layer that adopts a new structural design different from the prior art (for example, at least one of the elongated gaps or the gaps), and by combining the impedance adjustment layer with the ground layer, the impedance adjustment mechanism can be applied to the antenna mechanism with a smaller thickness, and at the same time, excellent antenna efficiency can be achieved.

[0042] Furthermore, the antenna device, antenna apparatus, and impedance adjustment mechanism disclosed in the embodiments of the present invention can radiate normally even when the total thickness of the detection antenna is less than 1% of the wavelength corresponding to the center frequency, and the detection antenna can achieve appropriate efficiency with respect to the total thickness.

[0043] The content disclosed above is only a preferred embodiment of the present invention and does not limit the scope of the claims of the present invention. Therefore, all equivalent technical modifications made based on the content of the specification and the accompanying drawings of the present invention shall be included in the scope of the claims of the present invention.

Description of Reference Numerals

[0044] 100 Antenna device 10 Antenna apparatus 1 Impedance adjustment mechanism 11 Ground layer 12 Impedance adjustment layer 121 Outer contour 122 Opening 123 Elongated gap 124 Inner gap 125 Outer gap 126 Gap 127 Circular layout area 13 Dielectric layer 131 Accommodation hole 2 Antenna mechanism 21 Electronic component 22 Detection antenna 23 Insulating layer 3 Carriers 4 Box 41 Storage space 5 Reader H Thickness direction R Layout distance C Center W123 Width S Adjustment block σ1 First angle σ2 Second angle σS Central angle H1 Thickness L1, L2, L3 Curves

Claims

1. An antenna device comprising a carrier, an impedance adjustment mechanism installed corresponding to the carrier, and an antenna mechanism installed in the impedance adjustment mechanism, wherein: The impedance adjustment mechanism includes: A ground layer installed on the carrier; An impedance adjustment layer installed at a distance from the ground layer, the projection area projected onto the ground layer being located inside the outer edge of the ground layer, and forming at least one elongated gap recessed from the outer contour toward the center; And includes: The thickness of the impedance adjustment mechanism is 0.4% to 25% of the wavelength of the center frequency applied by the antenna mechanism. An antenna device characterized by the above.

2. The antenna device includes a box body in which a plurality of storage spaces are formed, the carrier, the impedance adjustment mechanism, and the antenna mechanism are jointly installed in one of the plurality of storage spaces, and the antenna device includes a reader installed on the box body so as to read a signal output from the antenna mechanism. The antenna device according to claim 1.

3. The carrier is flat and plate-shaped, and the carrier is a high-loss dielectric. The antenna device according to claim 1.

4. An electronic component installed in the impedance adjustment mechanism; A detection antenna electrically coupled to the electronic component; An insulator layer installed on the impedance adjustment layer, supporting the detection antenna, and separating the impedance adjustment layer from the detection antenna. The antenna device according to claim 1, further comprising:

5. The impedance adjustment layer forms an aperture communicating with at least one of the elongated gaps, the electronic component is installed in the aperture, the area of the aperture does not exceed 10% of the area surrounded by the outer contour of the impedance adjustment layer, the impedance adjustment mechanism includes a dielectric layer sandwiched between the ground layer and the impedance adjustment layer, a receiving hole communicating with the aperture is formed in the dielectric layer, the electronic component is installed through the aperture and the receiving hole, and is installed on the ground layer. The antenna device according to claim 4.

6. The antenna projection area of the detection antenna projected onto the top surface of the impedance adjustment layer is completely located on the top surface and does not cover the gap. The antenna device according to claim 4.

7. The layout distance between the outer contour and the center of the impedance adjustment layer is 25% to 45% of the wavelength, and the antenna device according to claim 1.

8. The width of at least one of the elongated gaps does not exceed 3% of the wavelength, and the antenna device according to claim 1.

9. An impedance adjustment mechanism including a ground layer and an impedance adjustment layer, The impedance adjustment layer is installed at an interval from the ground layer, and a projection area where the impedance adjustment layer is orthogonally projected onto the ground layer is located inside the outer edge of the ground layer, At least one elongated gap recessed from the outer contour toward the center is formed in the impedance adjustment layer, An impedance adjustment mechanism characterized by the above.

10. The number of at least one of the elongated gaps is one, and the impedance adjustment layer forms two inner gaps from the center toward the outer contour, and the two inner gaps do not reach the outer contour, and each inner gap is positioned to form a first angle of 85 degrees to 165 degrees with the elongated gap. The impedance adjustment mechanism according to claim 9.

11. The number of at least one of the elongated gaps is one, and a plurality of inner gaps are formed in the impedance adjustment layer from the center toward the outer contour, and a plurality of outer gaps are formed in the impedance adjustment layer from the outer contour toward the center. The plurality of inner gaps do not reach the outer contour, the plurality of outer gaps do not reach the center, and an outer gap or the elongated gap is arranged between any two adjacent inner gaps. The impedance adjustment mechanism according to claim 9.

12. M adjustment blocks are defined in the impedance adjustment layer, M is a positive integer, and the M adjustment blocks are adjacent to each other and form an integral single structure. The impedance adjustment mechanism according to claim 11.

13. The number of at least one of the elongated gaps is N, where N is a positive integer, whereby the impedance adjustment layer is divided into N adjustment blocks separated from each other, each adjustment block having a central angle with respect to the center, and the difference in the central angles of any two of the adjustment blocks not exceeding 120 degrees. The impedance adjustment mechanism according to claim 9.

14. The impedance adjustment layer forms an opening that communicates with at least one of the elongated gaps and is located at the center. The impedance adjustment mechanism includes a dielectric layer sandwiched between the ground layer and the impedance adjustment layer. The dielectric layer forms a receiving hole that communicates with the opening, and the relative permittivity of the dielectric layer is 1 to 6. The impedance adjustment mechanism according to claim 9.

15. An antenna device comprising an impedance adjustment mechanism including a ground layer and an impedance adjustment layer, and an antenna mechanism, wherein the impedance adjustment layer is disposed at a distance from the ground layer, and a projection area where the impedance adjustment layer is orthogonally projected onto the ground layer is located inside the outer edge of the ground layer. A gap is formed in the impedance adjustment layer, the antenna mechanism is installed on the impedance adjustment mechanism, and the thickness of the impedance adjustment mechanism is 0.4% to 25% of the wavelength of the center frequency applied by the antenna mechanism. An antenna device characterized by this.

16. The gap is formed to extend from the center of the impedance adjustment layer toward its outer contour, and the gap does not reach the outer contour. The antenna device according to claim 15.

17. There is a layout distance between the outer contour of the impedance adjustment layer and its center, and the length of the gap exceeds 50% of the layout distance. The antenna device according to claim 15.

18. A circular layout area is defined in the impedance adjustment layer, the center of the circular layout area is the center of the impedance adjustment layer, the area of the circular layout area is 15% to 25% of the area surrounded by the outer contour of the impedance adjustment layer, and the gap intersects the circular layout area. The antenna device according to claim 15.

19. The gap does not pass through the center of the circular layout area. The antenna device according to claim 18.

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