Conductive mesh structure and antenna element including 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, and more particularly to a conductive mesh structure including intersecting conductive lines and a method for manufacturing an antenna element including the same. [Background technology]

[0002] In recent years, image display devices have been coupled to communication devices such as smartphones. As a result, the image display devices may include antennas for high-frequency or ultra-high-frequency communication. Furthermore, various sensor components such as touch sensors and fingerprint sensors are also coupled to the image display devices, thereby realizing various communication and sensing functions in addition to the display functions.

[0003] In the case of an antenna or sensor member, the member may contain a conductor such as a metal layer, which may reduce the transparency of the image display device and degrade the image quality.

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

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

[0006] Furthermore, in an antenna or sensor member using the mesh structure, the conductive lines must be designed to provide desired radiation characteristics and sensing sensitivity. Summary of the Invention [Problem 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 properties.

[0008] SUMMARY OF THE INVENTION It is an object of the present invention to provide an antenna element having improved optical and electrical properties. [Means for solving the problem]

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

[0010] 2. In the above item 1, the conductive mesh layer includes a unit cell defined by adjacent first conductive lines and second conductive lines; In the above formula 1, θ is the interior angle of the unit cell.

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

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

[0013] 5. The conductive mesh structure according to item 1, wherein 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 comprising the conductive mesh structure according to any of the preceding embodiments.

[0015] 7. The antenna element according to item 6, including a radiation electrode formed from the conductive mesh layer.

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

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

[0018] 10. The antenna element according to item 6, having a gain of 0 dBi or more at frequencies of 20 GHz or more. [Effects of the Invention]

[0019] A conductive mesh structure according to an embodiment of the present invention includes a base layer and a conductive mesh layer, and by adjusting the transmittance of the base layer and the conductive mesh layer, the transmittance of the conductive mesh structure can be adjusted to a predetermined range or higher. Furthermore, by adjusting the transmittance of the conductive mesh layer in consideration of the interior angle of a unit cell included in the conductive mesh layer, moire caused by regular overlapping between the conductive mesh structure and the pixel structure of an image display device can be suppressed.

[0020] This makes it possible to effectively improve the optical transmittance of the conductive mesh structure itself and suppress moire in the pixel structure.

[0021] The conductive mesh structure can be applied to, for example, an antenna element capable of mobile communication at high or ultra-high frequencies (e.g., 3G, 4G, 5G or higher), and can realize an antenna element that ensures sufficient gain in the high or ultra-high frequency band while also taking into consideration compatibility with image display devices. [Brief explanation of the drawings]

[0022] [Figure 1] FIG. 1 is a schematic plan view illustrating a conductive mesh structure according to an exemplary embodiment. [Figure 2] FIG. 2 is a partially enlarged plan view illustrating the structure of the conductive mesh layer of the conductive mesh structure according to the exemplary embodiment. [Figure 3] FIG. 3 is a schematic cross-sectional view illustrating an antenna element according to an exemplary embodiment. [Figure 4] FIG. 4 is a schematic plan view illustrating an antenna element according to an exemplary embodiment. DETAILED DESCRIPTION OF THE INVENTION

[0023] An embodiment of the present invention provides a conductive mesh structure that includes a substrate layer and a conductive mesh layer formed by intersecting conductive lines.

[0024] Furthermore, an embodiment of the present invention provides a method for manufacturing an antenna element using the conductive mesh structure. However, the conductive mesh structure manufactured by the embodiment of the present invention is not limited to antenna elements. The conductive mesh structure can be used in various electronic and electrical elements that require 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 in more detail with reference to the drawings. However, the drawings attached to this specification are intended to illustrate preferred embodiments of the present invention and, together with the detailed description of the invention, serve to further understand the technical concept of the present invention, and therefore the present invention should not be interpreted as being limited to only the matters depicted in the drawings.

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

[0027] 1, two directions that are parallel to the upper surface of the dielectric layer 90 and perpendicularly intersect each other are defined as a first direction and a 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] 1, the conductive mesh structure 100 may include a conductive mesh layer formed on a dielectric layer 90. The conductive mesh layer may include conductive lines 110 and 120.

[0029] The dielectric layer 90 may include a transparent resin material. For example, the dielectric layer 90 may include polyester-based resins such as polyethylene terephthalate, polyethylene isophthalate, polyethylene naphthalate, and polybutylene terephthalate; cellulose-based resins such as diacetyl cellulose and triacetyl cellulose; polycarbonate-based resins; acrylic-based resins such as polymethyl (meth)acrylate and polyethyl (meth)acrylate; styrene-based resins such as polystyrene and acrylonitrile-styrene copolymers; polyolefin-based resins such as polyethylene, polypropylene, polyolefins having cyclo- or norbornene structures, and ethylene-propylene copolymers; vinyl chloride-based resins; amide-based resins such as nylon and aromatic polyamides; imide-based resins; polyethersulfone-based resins; sulfone-based resins; polyetheretherketone-based resins; polyphenylene sulfide-based resins; vinyl alcohol-based resins; vinylidene chloride-based resins; vinyl butyral-based resins; arylate-based resins; polyoxymethylene-based resins; epoxy-based resins; urethane-based or acrylic urethane-based resins; silicone-based resins, etc. These may be used alone or in combination.

[0030] In some embodiments, the dielectric layer 90 may also include an adhesive film such as an optically clear adhesive (OCA) or an optically clear resin (OCR).

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

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

[0033] The conductive lines 110, 120 may 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 may extend in a diagonal direction relative to the first direction or the second direction.

[0034] For example, the first conductive line 110 may extend to be inclined clockwise with respect to the first direction, and the second conductive line 120 may extend to be inclined counterclockwise 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 lines 110 and the second conductive lines 120 may cross each other, thereby defining a plurality of unit cells 130 by the first conductive lines 110 and the second conductive lines crossing each other. The unit cells 130 may be defined as open areas of the conductive mesh layer.

[0037] As shown in FIG. 1, the unit cell 130 may have a diamond shape, and the smaller of the diamond's interior angles may be defined as the interior angle θ of the unit cell 130.

[0038] In some embodiments, the first conductive lines 110 can be arranged to be tilted at an angle of θ / 2 in a clockwise direction relative to the first direction, and the second conductive lines can be arranged to be tilted at an angle of θ / 2 in a counterclockwise direction relative to the first direction.

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

[0040] The conductive lines 110 and 120 may 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, which may be used alone or in combination of two or more thereof.

[0041] In one embodiment, to achieve low resistance, the conductive lines 110, 120 may 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 may also comprise a transparent conductive oxide such as indium tin oxide (ITO), indium zinc oxide (IZO), indium zinc tin oxide (ITZO), or zinc oxide (ZnOx).

[0043] In some embodiments, the conductive lines 110, 120 may have a multi-layer structure, such as a two-layer structure of a transparent conductive oxide layer and a metal layer, or a three-layer structure of a transparent conductive oxide layer, a metal layer, and a transparent conductive oxide layer. In this case, the metal layer can improve flexibility and reduce resistance, and the transparent conductive oxide layer can improve corrosion resistance and transparency.

[0044] For example, the conductive lines 110 and 120 may include a blackening treatment, which reduces the reflectivity on the surfaces of the conductive lines 110 and 120 and reduces the visibility of the patterns due to light reflection.

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

[0046] The composition and thickness of the blackening layer can be adjusted taking into consideration the effect of reducing reflectance and the radiation characteristics of the antenna.

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

[0048] Referring to FIG. 2, as described in FIG. 1, the conductive mesh layer may include unit cells 130 defined by intersecting first electrode lines 110 and second electrode lines 120, and may include open areas due to 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 formula 1:

[0050] [Formula 1] 18.5%≦(transmittance of 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 formula 2:

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

[0054] The open area ratio of the conductive mesh layer in Equation 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 Equation 3 below:

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

[0057] In Equation 3, X is the horizontal (second direction) diagonal length of the unit cell or open area, Y is the vertical (first direction) diagonal length of the unit cell or open area, W is the line width of the conductive line, and θ is the interior angle of the unit cell.

[0058] Within the ranges shown in the above formulas 1 to 3, the desired transmittance of the conductive mesh structure can be ensured while reducing or suppressing the occurrence of moire, for example, due to the regular overlap of the pixel structure and the conductive mesh layer pattern structure of an image display device.

[0059] For example, the value of tan(θ / 2), which reflects the interior angle θ of the unit cell 130, can act as a factor for suppressing the moire. As shown in Equation 1, by taking into consideration both the transmittance of the conductive mesh structure and tan(θ / 2), it is possible to ensure the optical characteristics of the conductive mesh structure itself while reducing the occurrence of moire due to interference with the pixel structure.

[0060] Furthermore, as shown in Equations 2 and 3, the interior angle θ of the unit cell 130 can also act as a factor for changing the transmittance of the conductive mesh structure, thereby enabling the design of a mesh structure that satisfies a predetermined transmittance while suppressing the occurrence of moire.

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

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

[0063] In some embodiments, the line width of the conductive lines 110, 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 formula 4 of 0.6 or less.

[0065] [Formula 4] Moiré index = (contrast) x (contrast sensitivity function (CSF) value)

[0066] In Equation 4, contrast represents the brightness difference expressed as the ratio of the brightness of the brightest part to the darkest part in a microscope image of the conductive line. For example, as the spacing or pitch between the conductive lines increases, the contrast increases, which increases the probability that a user will see a moire pattern.

[0067] The CSF value in Equation 1 is obtained from a contrast sensitivity function (CSF). The contrast sensitivity function (CSF) value may be a value that quantifies the sensitivity of the human visual system to repeated regular patterns. The CSF value can provide a numerical representation of the ability or possibility of discrimination by the human naked eye depending on the frequency of a pattern for an image with little difference in brightness. The larger the CSF value, the greater the probability that the regular overlap of the conductive lines 110 and 120 and pixels will be visible to the human naked eye.

[0068] Specifically, the CSF value can indicate the probability of human visibility, with spatial frequency, viewing angle, and average luminance as variables. Spatial frequency can be expressed as the number of cycles of light and dark areas in an optical image (e.g., cycles per millimeter (CPM)) or the reciprocal of the pitch of the conductive lines 110 and 120. Spatial frequency can also be converted into cycles per degree (CPD) for use. According to an exemplary embodiment, the spatial frequency can be measured by fixing the distance between the conductive lines 110 and 120 and the observer's eyes at 400 mm.

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

[0070] [Formula 5] JPEG0007698711000001.jpg12107

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

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

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

[0074] As described above, the interior angle θ of the unit cell is used as a moire adjustment factor, and the transmittance is also adjusted according to the interior angle θ, thereby suppressing moire while simultaneously controlling the optical properties of the conductive mesh structure 100 itself within a desired range.

[0075] 3 and 4 are schematic cross-sectional and plan views, respectively, of an antenna element according to an exemplary embodiment.

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

[0077] The antenna unit layer 140 may include the conductive mesh structure described above. 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 layer with the variables related to the transmittance and the interior angle of the unit cell adjusted according to Equations 1-3, as described in Figures 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 conductive mesh structure described above.

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

[0081] For example, a conductive layer may be formed on the dielectric layer 90. The conductive layer may be etched according to a design that satisfies variables related to transmittance and the interior angle of the unit cell in accordance with Equations 1 to 3 to form the first and second conductive lines 110 and 120, and the isolation region 175 may also be formed simultaneously by the etching process.

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

[0083] The dummy mesh pattern 170 includes the conductive mesh layer and is arranged around the antenna pattern, thereby leveling the distribution of the conductive pattern of the antenna element, thereby preventing the conductive lines 110, 120 or the conductive pattern from being visible to the user.

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

[0085] In some embodiments, ground pads 162 may be arranged around the signal pad 160. For example, a pair of ground pads 162 may be arranged with the signal pad 160 in between so as to be electrically and physically isolated from the transmission line 155 and the signal pad 160.

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

[0087] The signal pads 160 and ground pads 162 can be formed with solid patterns including the aforementioned metals or alloys, and in some embodiments, the signal pads 160 and ground pads 162 can be positioned so that they do not overlap with the pixel structure.

[0088] The antenna element may 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, a ground plane 80 may be included as a separate component of the antenna element. In some embodiments, a conductive member of a display device on which the antenna element is mounted may also serve as the ground plane.

[0090] The conductive member may include, for example, a gate electrode of a thin film transistor (TFT) included in a display panel, various wirings such as a scan line or a data line, or various electrodes such as a pixel electrode or a common electrode.

[0091] In one embodiment, various structures including a conductive material disposed under the display panel may 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. may be provided as the ground layer 80.

[0092] According to exemplary embodiments, the antenna elements can provide a sufficient amount of gain in high frequency or ultra-high frequency bands, and in some embodiments, the antenna elements can provide an antenna gain of 0 dBi or greater in frequency bands above 20 GHz.

[0093] Below, preferred examples are presented to help understand 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 to these examples within the scope and technical spirit of the present invention, and it goes without saying that these changes and modifications also fall within the scope of the appended claims.

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

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

[0096] [Table 1]

[0097] (1) Experimental example 1) Evaluation of moire Each of the conductive mesh structures of the examples and comparative examples was superimposed on a display panel including pixel structures collected from smartphones currently on the market, and 10 panelists observed whether or not the moire phenomenon occurred.

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

[0099] Specifically, ten panelists were asked to visually observe the moiré pattern, and the number of panelists who evaluated that the moiré pattern was clearly visible was counted to evaluate the visibility probability. The evaluation criteria are as follows (for example, if seven out of ten panelists evaluated that the moiré pattern was visible, the visibility probability is 70%).

[0100] <Moiré evaluation criteria> ○: The probability of moiré being visible is 20% or less △: Moire visibility probability is 20-50% ×: Probability of seeing moire is 60% or more

[0101] 2) Evaluation of antenna gain A single radiation pattern of 2.8 mm x 2.8 mm was formed using the conductive mesh structures of the examples and comparative examples, and the antenna gain (dBi) of the radiation pattern was measured at 28 GHz using a mmWave measuring device (manufactured by C&G Microwave).

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

[0103] [Table 2]

[0104] Referring to Table 1, in the examples that satisfy the numerical ranges described in the above Equations 1 to 3, gain values equal to or greater than a predetermined target gain (e.g., 0 dBi) for realizing antenna radiation while suppressing the moiré phenomenon were obtained.

[0105] For example, when the numerical value range of Equation 1 was approximately 20 to 55, the probability of moiré being visible was reduced to 20% or less in the pixel structure of one or more products.

Claims

1. a dielectric layer; a conductive mesh layer arranged on the dielectric layer and including first and second conductive lines that cross each other; the conductive mesh layer includes a unit cell defined by adjacent first and second conductive lines; An antenna element comprising a conductive mesh structure that satisfies the following formula 1 and formula 2. [Formula 1] 18.5%≦(transmittance of conductive mesh structure)×tan(θ / 2)≦60% [Formula 2] 18.5%≦(transmittance of dielectric layer)×(open area ratio of conductive mesh layer)×tan(θ / 2)≦60% (In Equation 1 and Equation 2, θ is the intersection angle between the first conductive line and the second conductive line or the interior 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 of 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 conductive mesh layer)=(XY) / {(X+2W×cos(θ / 2))(Y+2W×sin(θ / 2))} (In Equation 3, X is the length of the horizontal diagonal of the unit cell, Y is the length of the vertical diagonal of the unit cell, and W is the line width of the first conductive line and the second conductive line.)

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

4. The antenna element of claim 1 , comprising a radiating electrode formed from the conductive mesh layer.

5. The antenna element according to claim 4 , further comprising a transmission line formed from the conductive mesh layer and connected to the radiation electrode.

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

7. 10. The antenna element of claim 1, having a gain of 0 dBi or greater at frequencies of 20 GHz or greater.

Images