Conductive mesh structure and antenna element including the same

Abstract

The conductive mesh structure includes a dielectric layer and a conductive mesh layer arranged on the dielectric layer and including first and second conductive lines that intersect with each other. The conductive mesh layer satisfies predetermined ranges of transmittance and mesh unit cell interior angle. The conductive mesh structure can be used to manufacture antenna elements with reduced moiré.

Description

Technical Field

[0001] The present invention relates to a conductive mesh structure and an antenna element including the same. More specifically, the present invention relates to a conductive mesh structure including intersecting conductive lines and a method for manufacturing an antenna element including the same.

Background Art

[0002] In recent years, image display devices have been combined with communication devices such as smartphones. As a result, an antenna for realizing high-frequency or ultra-high-frequency communication may be included in the image display device. In addition, various sensor members such as a touch sensor and a fingerprint sensor are also combined with the image display device, and various communication and sensing functions are realized by adding them to the display function.

[0003] In the case of an antenna or a sensor member, it includes a conductor such as a metal layer, and the transparency of the image display device or the image quality may be deteriorated by the conductor.

[0004] Furthermore, when the mesh structure overlaps with a regular pattern structure and a pixel array structure included in an image display device, a moiré phenomenon may occur and interfere with the image of the image display device.

[0005] Therefore, it is necessary to design the conductive lines included in the mesh structure in consideration of both the transmittance of the mesh structure and the moiré with the pixel array structure of the image display device.

[0006] In addition, it is necessary to design the conductive lines so that the antenna or sensor member using the mesh structure can sufficiently provide desired radiation characteristics and sensing sensitivity.

Summary of the Invention

Problems to be Solved by the Invention

[0007] An object of the present invention is to provide a conductive mesh structure having improved optical and electrical characteristics.

[0008] An object of the present invention is to provide an antenna element having improved optical and electrical characteristics.

Means for Solving the Problems

[0009] 1. A conductive mesh structure including a dielectric layer and a conductive mesh layer arranged on the dielectric layer and including first conductive lines and second conductive lines that cross each other and satisfying the following formula (1). [Formula (1)] 18.5% ≦ (transmittance of the conductive mesh structure) × tan(θ / 2) ≦ 60% (In Formula (1), θ is the intersection angle between the first conductive line and the second conductive line.)

[0010] 2. The conductive mesh structure according to item 1 above, wherein the conductive mesh layer includes unit cells defined by adjacent first conductive lines and second conductive lines, and in Formula (1), θ is the interior angle of the unit cell.

[0011] 3. The conductive mesh structure according to item 2 above, wherein the conductive mesh structure satisfies the following formula (2). [Formula (2)] 18.5% ≦ (transmittance of the dielectric layer) × (open area ratio of the conductive mesh layer) × tan(θ / 2) ≦ 60%

[0012] 4. The conductive mesh structure according to item 3 above, wherein the open area ratio of the conductive mesh layer is defined by the following formula (3). [Formula (3)] (Open area ratio of the conductive mesh layer) = (XY) / {(X + 2W × COS(θ / 2))(Y + 2W × SIN(θ / 2))} (In Formula (3), X is the length of the diagonal in the horizontal direction of the unit cell, Y is the length of the diagonal in the vertical direction of the unit cell, and W is the line width of the first conductive line and the second conductive line.)

[0013] 5. In item 1 above, for the conductive mesh structure, the value of (transmittance of the conductive mesh structure) × tan(θ / 2) included in Formula 1 is 20 to 55%.

[0014] 6. An antenna element including the conductive mesh structure according to the above-described embodiment.

[0015] 7. In item 6 above, an antenna element including a radiation electrode formed from the conductive mesh layer.

[0016] 8. In item 7 above, an antenna element further including a transmission line formed from the conductive mesh layer and connected to the radiation electrode.

[0017] 9. In item 7 above, an antenna element further including a dummy mesh pattern formed from the conductive mesh layer and physically and electrically separated from the radiation electrode.

[0018] 10. In item 6 above, an antenna element having a gain of 0 dBi or more at a frequency of 20 GHz or higher.

Advantages of the Invention

[0019] The conductive mesh structure according to an embodiment of the present invention includes a base material layer and a conductive mesh layer, and by adjusting the transmittance of the base material layer and the transmittance of the conductive mesh layer, the transmittance of the conductive mesh structure can be adjusted to a predetermined range or more. Further, by adjusting the transmittance of the conductive mesh layer in consideration of the inner angles of the unit cells included in the conductive mesh layer, moiré due to regular superposition with the pixel structure of the conductive mesh structure and the image display device can be suppressed.

[0020] Thereby, both improvement of the optical transmittance of the conductive mesh structure itself and suppression of moiré of the pixel structure can be effectively realized.

[0021] The conductive mesh structure can be applied to, for example, antenna elements capable of mobile communication in the high-frequency or ultra-high-frequency band (e.g., 3G, 4G, 5G, or higher), and an antenna element can be realized that takes into account the compatibility with an image display device while ensuring sufficient gain in the high-frequency or ultra-high-frequency band.

Brief Description of the Drawings

[0022]

Figure 1

Figure 2

Figure 3

Figure 4

Modes for Carrying Out the Invention

[0023] Embodiments of the present invention provide a conductive mesh structure including a predetermined base material layer and a conductive mesh layer formed by intersecting conductive lines.

[0024] In addition, embodiments of the present invention provide a method for manufacturing an antenna element utilizing the conductive mesh structure. However, the conductive mesh structure manufactured according to embodiments of the present invention is not only applicable to antenna elements. The conductive mesh structure can be utilized in various electronic and electrical elements that require characteristics such as high transparency and low resistance, such as touch sensors, fingerprint sensors, optical filters, and electromagnetic wave filters.

[0025] Hereinafter, embodiments of the present invention will be described more specifically with reference to the drawings. However, the drawings attached to this specification illustrate preferred embodiments of the present invention and serve to assist in further understanding the technical idea of the present invention together with the detailed description of the invention. Therefore, the present invention is not construed as being limited only to the matters described in the drawings.

[0026] FIG. 1 is a schematic plan view showing a conductive mesh structure according to an exemplary embodiment.

[0027] In FIG. 1, two directions that are parallel to the upper surface of the dielectric layer 90 and intersect each other perpendicularly are defined as the first direction and the second direction. For example, the first direction may correspond to the longitudinal direction of the conductive mesh structure, and the second direction may correspond to the width direction of the conductive mesh structure.

[0028] Referring to FIG. 1, the conductive mesh structure 100 can include a conductive mesh layer formed on the dielectric layer 90. The conductive mesh layer can include conductive lines 110 and 120.

[0029] The dielectric layer 90 can include a transparent resin material. For example, the dielectric layer 90 can be a polyester resin such as polyethylene terephthalate, polyethylene isophthalate, polyethylene naphthalate, polybutylene terephthalate; a cellulose resin such as diacetyl cellulose, triacetyl cellulose; a polycarbonate resin; an acrylic resin such as polymethyl (meth)acrylate, polyethyl (meth)acrylate; a styrene resin such as polystyrene, acrylonitrile-styrene copolymer; a polyolefin resin such as polyethylene, polypropylene, a polyolefin having a cyclo or norbornene structure, ethylene-propylene copolymer; a vinyl chloride resin; an amide resin such as nylon, aromatic polyamide; an imide resin; a polyethersulfone resin; a sulfone resin; a polyetheretherketone resin; a sulfurized polyphenylene resin; a vinyl alcohol resin; a vinylidene chloride resin; a vinyl butyral resin; an allylate resin; a polyoxymethylene resin; an epoxy resin; a urethane or acrylic urethane resin; a silicon resin, etc. These can be used alone or in combination of two or more.

[0030] In some embodiments, also, an adhesive film such as an Optically clear Adhesive (OCA), an Optically Clear Resin (OCR), etc. can be included in the dielectric layer 90.

[0031] In some embodiments, the dielectric layer 90 can also include an inorganic insulating material such as glass, silicon oxide, silicon nitride, silicon oxynitride.

[0032] In some embodiments, the dielectric constant of the dielectric layer 90 can be adjusted in the range of about 1.5 to 12. When the dielectric constant exceeds about 12, the signal loss increases too much, and the signal sensitivity and signal efficiency during high-frequency band communication may decrease.

[0033] The conductive lines 110 and 120 can include a first conductive line 110 and a second conductive line 120. As shown in FIG. 1, the first conductive line 110 and the second conductive line 120 can extend in a diagonal direction with respect to the first direction or the second direction.

[0034] For example, the first conductive line 110 can extend so as to be inclined in a clockwise direction with respect to the first direction. The second conductive line 120 can extend so as to be inclined in a counterclockwise direction with respect to the first direction.

[0035] In some embodiments, the first conductive line 110 and the second conductive line can be arranged symmetrically with respect to the first direction.

[0036] The first conductive line 110 and the second conductive line 120 can intersect with each other. Thereby, a plurality of unit cells 130 can be defined by the intersecting and adjacent first conductive line 110 and second conductive line. The unit cell 130 can be defined as an open region of the conductive mesh layer.

[0037] As shown in FIG. 1, the unit cell 130 can have a rhombus shape, and the smaller interior angle among the interior angles of the rhombus can be defined as the interior angle θ of the unit cell 130.

[0038] In some embodiments, the first conductive line 110 can be arranged to be inclined at an angle of θ / 2 in a clockwise direction with respect to the first direction. The second conductive line can be arranged to be inclined at an angle of θ / 2 in a counterclockwise direction with respect to the first direction.

[0039] Thereby, the interior angle θ of the unit cell 130 can be defined by the intersection angle of the first conductive line 110 and the second conductive line 120. The conductive mesh layer can include the open region defined by repeating a plurality of unit cells 130 and a conductor region defined by the conductive lines 110 and 120.

[0040] The conductive lines 110, 120 can include silver (Ag), gold (Au), copper (Cu), aluminum (Al), platinum (Pt), palladium (Pd), chromium (Cr), titanium (Ti), tungsten (W), niobium (Nb), tantalum (Ta), vanadium (V), iron (Fe), manganese (Mn), cobalt (Co), nickel (Ni), zinc (Zn), tin (Sn), molybdenum (Mo), calcium (Ca), or an alloy containing at least one of these. These can be used alone or in combination of two or more.

[0041] In one embodiment, for realizing low resistance, the conductive lines 110, 120 can include silver or a silver-containing alloy (e.g., silver-palladium-copper (APC)), or copper or a copper-containing alloy (e.g., copper-calcium (CuCa)).

[0042] In some embodiments, the conductive lines 110, 120 can also include a transparent conductive oxide such as indium tin oxide (ITO), indium zinc oxide (IZO), indium zinc tin oxide (ITZO), zinc oxide (ZnOx).

[0043] In some embodiments, the conductive lines 110, 120 can also have a multilayer structure such as a two-layer structure of a transparent conductive oxide layer - metal layer, or a three-layer structure of a transparent conductive oxide layer - metal layer - transparent conductive oxide layer. In this case, the metal layer can improve the flexible characteristics while reducing the resistance, and the transparent conductive oxide layer can improve the corrosion resistance and transparency.

[0044] For example, the conductive lines 110, 120 can include a blackening treatment part. Thereby, the reflectance on the surface of the conductive lines 110, 120 can be reduced, and the visual recognition of the pattern due to light reflection can be reduced.

[0045] In one embodiment, the surface of the metal layer included in the conductive lines 110 and 120 can be converted into a metal oxide or a metal sulfide to form a blackened layer. In one embodiment, a blackened layer such as a black material coating layer or a plating layer can be formed on the conductive lines 110 and 120 or the metal layer. The black material or the plating layer can include oxides, sulfides, alloys, etc. containing silicon, carbon, copper, molybdenum, tin, chromium, molybdenum, nickel, cobalt, or at least one of these.

[0046] The composition and thickness of the blackened layer can be adjusted in consideration of the reflectivity reduction effect and the radiation characteristics of the antenna.

[0047] FIG. 2 is a partially enlarged plan view for explaining the structure of the conductive mesh layer of the conductive mesh structure according to an exemplary embodiment.

[0048] Referring to FIG. 2, as described in FIG. 1, the conductive mesh layer includes unit cells 130 defined by intersecting first electrode lines 110 and second electrode lines 120, and can include open regions formed by the internal spaces of the unit cells 130.

[0049] According to an exemplary embodiment, the conductive mesh structure including the conductive mesh layer can satisfy the following Equation 1.

[0050] [Equation 1] 18.5% ≦ (transmittance of the conductive mesh structure) × tan(θ / 2) ≦ 60%

[0051] In Equation 1, θ represents the interior angle of the unit cell 130 as described above.

[0052] In some embodiments, the conductive mesh structure including the conductive mesh layer can satisfy the following Equation 2.

[0053] [Equation 2] 18.5% ≦ (transmittance of the dielectric layer) × (open region ratio of the conductive mesh layer) × tan(θ / 2) ≦ 60%

[0054] The open area ratio of the conductive mesh layer in Formula 2 may be the ratio of the area of the open area to the area of the conductive mesh layer.

[0055] In one embodiment, the open area ratio of the conductive mesh layer can be defined by the following Formula 3.

[0056] [Formula 3] (Open area ratio of conductive mesh layer) = (XY) / {(X + 2W×COS(θ / 2))(Y + 2W×SIN(θ / 2))}

[0057] In Formula 3, X is the length of the diagonal in the lateral direction (second direction) of the unit cell or the open area, Y is the length of the diagonal in the longitudinal direction (first direction) of the unit cell or the open area. W is the line width of the conductive line, and θ represents the inner angle of the unit cell.

[0058] Within the ranges shown in the above Formulas 1 to 3, while ensuring the desired transmittance of the conductive mesh structure, for example, the occurrence of moiré due to the regular superposition of the pixel structure of the image display device and the conductive mesh layer pattern structure can be reduced or suppressed.

[0059] For example, the value of tan(θ / 2) reflecting the inner angle θ of the unit cell 130 can act as a factor for suppressing the moiré. As shown in Formula 1, while considering both the transmittance of the conductive mesh structure and tan(θ / 2) to ensure the optical characteristics of the conductive mesh structure itself, the occurrence of moiré due to the interference with the pixel structure can be reduced together.

[0060] Also, as shown in Formulas 2 and 3, the inner angle θ of the unit cell 130 can also act as a factor for changing the transmittance of the conductive mesh structure. Thereby, it is possible to realize the design of the mesh structure in which the occurrence of moiré is suppressed while satisfying a predetermined transmittance.

[0061] Also, as an adjustment variable for the transmittance of the conductive mesh structure, the line widths W of the conductive lines 110 and 120 can both be controlled. For example, in order to ensure sufficient current flow, electric field generation, and antenna gain, an appropriate range of line width (W) can be set, and the factors included in Equation 3 can be adjusted to satisfy the range shown in Equation 1. Thereby, improvement of electrical characteristics and optical transmittance, and suppression of moiré can be effectively realized by adjusting the numerical range of Equation 1 according to the exemplary embodiments.

[0062] In some embodiments, the value of (transmittance of the conductive mesh structure) × tan(θ / 2) included in Equation 1 may be 20 to 55%, preferably 20 to 40%, more preferably 25 to 40%.

[0063] In some embodiments, the line widths of the conductive lines 110 and 120 can be adjusted in the range of about 1 to 5 μm.

[0064] In some embodiments, the conductive mesh layer may have a moiré index defined by the following Equation 4 of 0.6 or less.

[0065] [Equation 4] Moiré index = (contrast) × (value of the contrast sensitivity function (CSF))

[0066] In Equation 4, the contrast represents the brightness difference indicated by the ratio of the brightness of the brightest part and the darkest part in the microscopic image of the conductive line. For example, as the interval or pitch between the conductive lines increases, the contrast increases, thereby increasing the probability of causing the user to visually recognize the moiré pattern.

[0067] The value of the CSF of Equation 1 is obtained from the Contrast Sensitivity Function (CSF). The value of the Contrast Sensitivity Function (CSF) may be a value obtained by quantifying the sensitivity due to the repetition of a regular pattern in the human visual system. Based on the value of the CSF, it is possible to quantify and provide the discrimination ability or discriminability by the human naked eye according to the pattern frequency for an image with a small difference in brightness. As the value of the CSF increases, the probability of being visually recognized by the human naked eye due to the regular superposition of the conductive lines 110 and 120 and the pixels can increase.

[0068] Specifically, the value of the CSF can indicate the probability of being visually recognized by humans with spatial frequency, viewing angle, and average luminance as variables. The spatial frequency can be represented by the cycle (e.g., cycles per millimeter (CPM)) of the bright and dark parts in the optical image or the reciprocal of the pitch of the conductive lines 110 and 120. The spatial frequency can also be converted to cycles per degree (CPD) for use. According to an exemplary embodiment, the spatial frequency can be measured with the distance between the conductive lines 110 and 120 and the observer's eyes fixed at 400 mm.

[0069] The value of the CSF can be calculated from the functions of Equation 5, Equation 5-1, and Equation 5-2 below.

[0070] [Equation 5] JPEG0007698711000001.jpg12107

[0071] [Equation 5-1] JPEG0007698711000002.jpg1781

[0072] [Equation 5-2] JPEG0007698711000003.jpg1165

[0073] In Formulas 5, 5-1, and 5-2, L represents the average luminance (unit: nt = cd / m 2 ), ω represents the viewing angle (degree), and f represents the spatial frequency (cycles per degree).

[0074] As described above, by using the inner angle θ of the unit cell as a moiré adjustment factor and adjusting the transmittance together with the inner angle θ to suppress moiré, the optical characteristics of the conductive mesh structure 100 itself can be controlled within a desired range together.

[0075] FIG. 3 and FIG. 4 are a schematic cross-sectional view and a plan view showing an antenna element according to an exemplary embodiment, respectively.

[0076] Referring to FIGS. 3 and 4, the antenna element may include an antenna unit layer 140 formed on the upper surface of the dielectric layer 90.

[0077] The antenna unit layer 140 may include the above-described conductive mesh structure. According to an exemplary embodiment, the antenna unit layer 140 may include a radiation pattern 150 and a transmission line 155 extending from one side or one end of the radiation pattern 150.

[0078] The radiation pattern 150 and the transmission line 155 may include a conductive mesh structure or a conductive mesh layer in which variables related to the transmittance and the inner angle of the unit cell are adjusted according to Formulas 1 to 3 as described in FIGS. 1 and 2.

[0079] In some embodiments, the antenna unit layer 140 may further include a dummy mesh pattern 170 formed around the radiation pattern 150. The dummy mesh pattern 170 may also include the above-described conductive mesh structure.

[0080] The dummy mesh pattern 170 can be separated from the radiation pattern 150 and the transmission line 155 by the separation region 175. In some embodiments, the separation region 175 can be formed together with the first and second conductive lines 110, 120.

[0081] For example, a conductive layer can be formed on the dielectric layer 90. The conductive layer is etched along a design that satisfies the variables regarding the transmittance and the inner angles of the unit cells according to Formulas 1 to 3 to form the first and second conductive lines 110, 120, and the separation region 175 can be simultaneously formed by the etching process.

[0082] The dummy mesh pattern 170 can also be formed around the transmission line 155. In some embodiments, a plurality of antenna patterns including the radiation pattern 150 and the transmission line 155 are formed on the dielectric layer 90, and the dummy mesh pattern 170 can be formed around or between the plurality of antenna patterns.

[0083] When the dummy mesh pattern 170 includes the conductive mesh layer and is disposed around the antenna pattern, the distribution of the conductive pattern of the antenna element can be equalized. Thereby, it is possible to prevent the conductive lines 110, 120 or the conductive pattern from being visually recognized by the user.

[0084] The antenna unit layer 140 can include a signal pad 160 connected to one end of the transmission line 155. The signal pad 160 can be electrically connected to an antenna driving integrated circuit (IC) chip via, for example, a flexible printed circuit board (FPCB). Thereby, power can be supplied to the radiation pattern 150 and a driving signal can be applied via the signal pad 160 by the antenna driving IC chip.

[0085] In some embodiments, ground pads 162 can be disposed around the signal pad 160. For example, a pair of ground pads 162 can be disposed on both sides of the signal pad 160 so as to be electrically and physically separated from the transmission line 155 and the signal pad 160.

[0086] The ground pads 162 can absorb or shield noise around the signal pad 160, and the bonding process of the FPCB to the antenna element can be performed more easily.

[0087] The signal pad 160 and the ground pads 162 can be formed as solid patterns filled with the aforementioned metal or alloy. In some embodiments, the signal pad 160 and the ground pads 162 can be arranged so as not to overlap with the pixel structure.

[0088] The antenna element can further include a ground layer 80 disposed on the bottom surface of the dielectric layer 90. The ground layer 80 can further promote the generation of an electric field in the radiation pattern 150 and the transmission line 155, and can absorb or shield electrical noise around the radiation pattern 150 and the transmission line 155.

[0089] In some embodiments, the ground layer 80 can be included as another configuration of the antenna element. In some embodiments, a conductive member of the display device on which the antenna element is mounted can also be provided as the ground layer.

[0090] The conductive member can include, for example, gate electrodes of thin film transistors (TFTs) included in the display panel, various wirings such as scan lines or data lines, or various electrodes such as pixel electrodes and common electrodes.

[0091] In one embodiment, for example, various structures including a conductive material disposed under the display panel can also be provided as the ground layer 80. For example, a metal plate (e.g., a stainless steel plate such as a SUS plate), a pressure sensor, a fingerprint sensor, an electromagnetic wave shielding layer, a heat dissipation sheet, a digitizer, etc. can be provided as the ground layer 80.

[0092] According to an exemplary embodiment, the antenna element can provide a sufficient gain amount in a high frequency or ultra-high frequency band. In some embodiments, the antenna element can provide an antenna gain of 0 dBi or more in a frequency band of 20 GHz or higher.

[0093] Hereinafter, preferred examples are presented to assist in understanding the present invention, but these examples are merely illustrative of the present invention and do not limit the scope of the appended claims. It is obvious to those skilled in the art that various changes and modifications can be made within the scope of the present invention and the scope of the technical idea, and it is natural that these variations and modifications belong to the scope of the appended claims.

[0094] Experimental Example (1) Examples and Comparative Examples On a COP dielectric layer with a transmittance of 91.1%, a first conductive line and a second conductive line containing CuCa were formed under the conditions shown in Table 1 (see FIG. 1) to form a conductive mesh layer, and a conductive mesh structure was obtained.

[0095] Using the transmittance of the conductive mesh structure and the inner angle of the unit cell measured from each of the conductive mesh structures of the examples and the comparative examples, numerical values calculated from Equations 1 to 3 were obtained. Specifically, the visual transmittance (Y_D65) was measured with a spectrophotometer (CM-3600A, Konica Minolta) under the conditions of a 2D observer to measure the transmittance of the conductive mesh structure.

[0096]

Table 1

[0097] (1) Experimental Example 1) Moiré Evaluation The conductive mesh structures of the examples and comparative examples were each superimposed on a display panel including a pixel structure collected from currently commercially available smartphones, and 10 panelists were allowed to observe the occurrence of the moiré phenomenon.

[0098] As the smartphones, Product A (Mate 30 Pro: manufactured by Huawei), Product B (I-Phone X: manufactured by Apple), Product C (Galaxy S10 5G: manufactured by Samsung Electronics), and Product D (Galaxy Note 8: manufactured by Samsung Electronics) were used. For each of the four products, the moiré phenomenon caused by the conductive mesh structure was observed.

[0099] Specifically, 10 panelists were visually observed, and the visibility probability was evaluated by counting the number of panelists who evaluated that the moiré pattern was clearly visible. The evaluation criteria are as follows (for example, when 7 out of 10 people were evaluated as visible, the visibility probability is 70%).

[0100] <Moiré Evaluation Criteria> ○: Moiré visibility probability is 20% or less △: Moiré visibility probability is 20 - 50% ×: Moiré visibility probability is 60% or more

[0101] 2) Antenna Gain Evaluation Using the conductive mesh structures of the examples and comparative examples, a single radiation pattern with a size of 2.8 mm × 2.8 mm was formed, and the antenna gain (dBi) of the radiation pattern was measured using a mmWave measuring instrument (manufactured by C&G Microwave) under the condition of 28 GHz.

[0102] The evaluation results are as shown in Table 2 below.

[0103] [Table 2]

[0104] Referring to Table 1, in the examples that satisfy the numerical ranges described by the above Formulas 1 to 3, while suppressing moiré phenomena, a gain value of a predetermined target gain (for example, 0 dBi) or more for realizing antenna radiation was obtained.

[0105] For example, when the numerical range of Formula 1 is in the range of about 20 to 55, the visual recognition probability of moiré decreased to 20% or less in the pixel structures of one or more products.

Claims

1. A dielectric layer, and a conductive mesh layer arranged on the dielectric layer and including first conductive lines and second conductive lines that intersect each other, wherein the conductive mesh layer includes unit cells defined by adjacent ones of the first conductive lines and the second conductive lines, and an antenna element including a conductive mesh structure satisfying the following Formula 1 and the following Formula 2. [Formula 1] 18.5% ≤ (transmittance of the conductive mesh structure) × tan(θ / 2) ≤ 60% [Formula 2] 18.5% ≤ (transmittance of the dielectric layer) × (open area ratio of the conductive mesh layer) × tan(θ / 2) ≤ 60% (In Formula 1 and Formula 2, θ is the intersection angle between the first conductive line and the second conductive line or the inner angle of the unit cell, and the open area ratio of the conductive mesh layer is the ratio of the area of the open area defined by the unit cell to the area of the conductive mesh layer.)

2. The antenna element according to Claim 1, wherein the open area ratio of the conductive mesh layer is defined by the following Formula 3. [Formula 3] (Open area ratio of the conductive mesh layer) = (XY) / {(X + 2W × COS(θ / 2))(Y + 2W × SIN(θ / 2))} (In Formula 3, X is the length of the diagonal in the horizontal direction of the unit cell, Y is the length of the diagonal in the vertical direction of the unit cell, and W is the line width of the first conductive line and the second conductive line.)

3. The antenna element according to Claim 1, wherein the value of (transmittance of the conductive mesh structure) × tan(θ / 2) included in Formula 1 is 20 to 55%.

4. The antenna element according to Claim 1, including a radiating electrode formed from the conductive mesh layer.

5. The antenna element according to Claim 4, further including a transmission line formed from the conductive mesh layer and connected to the radiating electrode.

6. The antenna element according to Claim 4, further including a dummy mesh pattern formed from the conductive mesh layer and physically and electrically separated from the radiating electrode.

7. The antenna element according to Claim 1, having a gain of 0 dBi or more at a frequency of 20 GHz or higher.

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