Circuit board, antenna structure including the same, and image display device including the same

Abstract

To provide a circuit board, an antenna structure including the same, and an image display device including the same, which have improved electrical reliability.SOLUTION: According to an embodiment of the present disclosure, there are provided a circuit board, an antenna structure including the circuit board, and an image display device including the antenna structure. The circuit board includes a core layer including a wiring portion and a ground portion arranged around the wiring portion, circuit wiring extending on the wiring portion, a first ground pattern arranged around the circuit wiring and spaced apart from the circuit wiring, and a first via structure arranged in the ground portion, penetrating the core layer, but not in the wiring portion.SELECTED DRAWING: Figure 1

Description

[Technical Field]

[0001] The present invention relates to a circuit board, an antenna structure including the same, and an image display device including the same. [Background technology]

[0002] In recent years, with the development of the information society, wireless communication technologies such as Wi-Fi and Bluetooth (registered trademark) have been combined with image display devices, for example, in the form of smartphones, in which an antenna is coupled to the image display device to perform communication functions.

[0003] Recently, with the advancement of mobile communication technology, it has become necessary to couple an antenna for communication in, for example, a high frequency or ultra-high frequency band to the image display device.

[0004] However, as the driving frequency of the antenna increases, signal loss can increase, and as the length of the transmission path increases, the degree of signal loss can increase even more.

[0005] For example, a circuit board including circuit wiring and connection intermediary structures such as via structures may be used to connect an antenna to a main board of an image display device, and in this case, signal interference or signal loss caused by bending or deformation of the circuit board may degrade the performance of the antenna. Summary of the Invention [Problem to be solved by the invention]

[0006] One object of the present invention is to provide a circuit board having improved electrical reliability.

[0007] It is an object of the present invention to provide an antenna structure with improved electrical reliability.

[0008] An object of the present invention is to provide an image display device having improved electrical reliability. [Means for solving the problem]

[0009] 1. A circuit board comprising: a core layer including a wiring portion and a ground portion arranged around the wiring portion; circuit wiring extending on the wiring portion; a first ground pattern arranged around the circuit wiring and spaced apart from the circuit wiring; and a first via structure arranged in the ground portion, penetrating the core layer, and not arranged in the wiring portion.

[0010] 2. The circuit board according to item 1, wherein the circuit wiring is not disposed on the ground portion.

[0011] 3. The circuit board according to item 1, wherein the circuit wiring includes a plurality of circuit wirings extending on the wiring portion, and the distance between the ground portion and the outermost circuit wiring of the plurality of circuit wirings is three times or more the line width of the circuit wiring.

[0012] 4. The circuit board according to item 1, wherein the core layer includes a first surface and a second surface facing each other, the circuit wiring and the first ground pattern are disposed on the first surface, and the circuit board further includes a second ground pattern disposed on the second surface.

[0013] 5. The circuit board according to item 4, wherein the first via structure electrically connects the first ground pattern and the second ground pattern.

[0014] 6. The circuit board according to item 1, wherein the first via structure includes a plurality of first via structures each penetrating the core layer in the ground portion.

[0015] 7. The circuit board according to item 6, wherein the plurality of first via structures include outer via structures arranged continuously along the outermost portion of the circuit board.

[0016] 8. The circuit board according to item 7, wherein the plurality of first via structures include internal via structures excluding the external via structure.

[0017] 9. The circuit board according to item 8, wherein the distance between adjacent internal via structures is greater than the distance between adjacent external via structures.

[0018] 10. The circuit board according to item 1, wherein the core layer includes a first extension, a bent portion connected to the first extension, and a second extension connected to the bent portion and facing the first extension.

[0019] 11. The circuit board according to item 1, further comprising a second via structure that penetrates the core layer and is connected to an end of the circuit wiring.

[0020] 12. The circuit board according to item 1, further comprising a protective layer covering the circuit wiring and the first ground pattern.

[0021] 13. An antenna structure comprising the aforementioned circuit board and an antenna element electrically connected to the circuit board.

[0022] 14. An antenna structure according to item 13, wherein the antenna element includes a radiator and a transmission line connected to the radiator, and the transmission line and the circuit wiring are electrically connected.

[0023] 15. An image display device comprising a display panel and the antenna structure described above. [Effects of the Invention]

[0024] According to an exemplary embodiment of the present invention, the core layer includes a bent portion, thereby improving the space efficiency of a device (for example, an image display device) that includes a circuit board.

[0025] According to an exemplary embodiment of the present invention, the first via structure may be disposed in the ground portion of the circuit board and penetrate the core layer, but may not be disposed in the wiring portion through which the circuit wiring extends. This can suppress the generation of unnecessary electric fields around the circuit wiring due to bending of the circuit board, thereby preventing signal loss. Therefore, it is possible to achieve antenna performance that is substantially equivalent to or similar to that of a non-bent circuit board. [Brief explanation of the drawings]

[0026] [Figure 1] FIG. 1 is a schematic plan view illustrating a circuit board according to an exemplary embodiment. [Figure 2] FIG. 2 is a schematic cross-sectional view illustrating a circuit board according to an exemplary embodiment. [Figure 3] FIG. 3 is a schematic plan view illustrating a circuit board according to an exemplary embodiment. [Figure 4] FIG. 4 is a schematic cross-sectional view illustrating an antenna structure according to an exemplary embodiment. [Figure 5] FIG. 5 is a schematic plan view illustrating an antenna structure according to an exemplary embodiment. [Figure 6] FIG. 6 is a schematic cross-sectional view showing an image display device according to an exemplary embodiment. [Figure 7] FIG. 7 is a schematic plan view showing an image display device according to an exemplary embodiment. [Figure 8] FIG. 8 is a schematic plan view showing antenna structures according to the reference example and the comparative example. [Figure 9] FIG. 9 is an image showing electric field generation diagrams of the antenna structures of the example and the comparative example. [Figure 10] FIG. 10 is a graph showing the antenna peak gain as a function of frequency for the antenna structures of the reference example, the working example, and the comparative example. DETAILED DESCRIPTION OF THE INVENTION

[0027] According to an embodiment of the present invention, there is provided a circuit board including a circuit wiring, an antenna structure including the circuit board, and an image display device including the circuit board or the antenna structure.

[0028] 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.

[0029] 1 and 2 are respectively a schematic plan view and a cross-sectional view showing a circuit board according to an exemplary embodiment, and Fig. 2 is a cross-sectional view of the circuit board of Fig. 1 taken along a wiring portion CP.

[0030] Referring to FIGS. 1 and 2, a circuit board 100 may include a core layer 105, a circuit wiring 110, a first ground pattern 120, and a first via structure .

[0031] The core layer 105 can include a wiring portion CP and a ground portion GP arranged around the wiring portion CP.

[0032] For example, the wiring portion CP may include an area where the circuit wiring 110 is arranged on the circuit board 100. For example, the ground portion GP may represent an area on the circuit board 100 excluding the wiring portion CP.

[0033] For example, the ground portion GP can surround the wiring portion CP.

[0034] For example, the circuit wiring 110 does not have to be disposed on the ground part GP.

[0035] The core layer 105 may include a first surface 105a and a second surface 105b facing each other.

[0036] In an exemplary embodiment, the core layer 105 may include a first extension 102, a bent portion 104 connected to the first extension 102, and a second extension 106 connected to the bent portion 104 and facing the first extension 102. For example, the first extension 102 and the second extension 106 may be disposed on opposite sides of the bent portion 104.

[0037] For example, the bending portion 104 may be provided as a region where the circuit board 100 is bent. As shown in Fig. 2, the circuit board 100 may be bent at the bending portion 104 so that the first surface 105a of the first extension portion 102 and the first surface 105a of the second extension portion face each other. This may improve the space efficiency of a device (e.g., an image display device) including the circuit board 100.

[0038] For example, the core layer 105 may include a flexible resin such as a polyimide resin, a modified polyimide (MPI), an epoxy resin, a polyester, a cycloolefin polymer (COP), a liquid crystal polymer (LCP), etc. For example, the core layer 105 may include an internal insulating layer included in the circuit board 100.

[0039] In an exemplary embodiment, the circuit wiring 110 and the first ground pattern 120 may be disposed on the first surface 105 a of the core layer 105 .

[0040] A plurality of circuit wirings 110 may extend onto the first surface 105a of the core layer 105.

[0041] In some embodiments, the distance D between the ground portion GP and the outermost circuit wiring of the circuit wiring 110 may be three times or more the line width of the circuit wiring 110, and in one embodiment, may be 3 to 200 times the line width of the circuit wiring 110. In this range, it is possible to suppress the generation of an unnecessary electric field due to bending of the circuit board 100 around the circuit wiring 110, and improve the antenna gain.

[0042] The "circuit wiring at the outermost periphery of the circuit wirings 110" can refer to the circuit wiring among the plurality of circuit wirings 110 that is closest to the ground part GP.

[0043] The first ground pattern 120 can be arranged around the circuit wiring 110 at a distance from the circuit wiring 110. This makes it possible to suppress noise around the circuit wiring 110.

[0044] For example, the first ground pattern 120 and the circuit wiring 110 can be arranged on the same layer or level.

[0045] In some embodiments, the first ground pattern 120 may include a first ground portion 120a arranged on the first surface 105a of the first extension portion 102 and a second ground portion 120b arranged on the first surface 105a of the second extension portion 106.

[0046] For example, the first ground pattern 120 may further include a bent ground portion 120c disposed between the first ground portion 120a and the second ground portion 120b and disposed on the first surface 105a of the bending portion 104. The bent ground portion 120c may be bent along the bending profile of the bending portion 104 of the core layer 105.

[0047] For example, the first ground portion 120a, the bent ground portion 120c, and the second ground portion 120b may be formed substantially integrally.

[0048] In an exemplary embodiment, the first via structure 130 may be disposed in the ground portion GP of the circuit board 100 and penetrate the core layer 105, but may not be disposed in the wiring portion CP. This can suppress the generation of unnecessary electric fields around the circuit wiring 110 due to bending of the circuit board 100, thereby preventing signal loss. Therefore, it is possible to achieve antenna performance that is substantially equivalent to or similar to that of a non-flexible circuit board 100.

[0049] In the comparative example in which the first via structure 130 is disposed in the wiring portion CP, interference capacitance occurs due to bending of the circuit board 100 around the circuit wiring 110, and the antenna gain may decrease.

[0050] In an exemplary embodiment, a plurality of first via structures 130 may be arranged in the ground portion GP.

[0051] In some embodiments, the plurality of first via structures 130 may include outer periphery via structures 132 arranged consecutively along the outermost periphery of the circuit board 100 .

[0052] In some embodiments, the plurality of first via structures 130 may include an inner via structure 134 excluding the outer via structure 132 .

[0053] In some embodiments, the distance between adjacent internal via structures 134 may be greater than the distance between adjacent external via structures 132. This can further shield noise, improve process efficiency, and improve the electrical reliability of the circuit board 100.

[0054] According to one embodiment, the distance between adjacent outer shell via structures 132 may be substantially uniform.

[0055] According to one embodiment, the distance between adjacent internal via structures 134 may be substantially uniform.

[0056] In some embodiments, the circuit board 100 may further include a second ground pattern 140 disposed on the second surface 105b of the core layer 105. This can improve the concentration of the electric field of the signal transmitted to the circuit wiring 110 and shield noise.

[0057] For example, the first via structure 130 can penetrate the core layer 105 in the ground portion GP to electrically connect the first ground pattern 120 and the second ground pattern 140. This improves the signal integrity between the first surface 105a and the second surface 105b of the core layer 105, and suppresses signal loss.

[0058] For example, the first via structure 130 can overlap with each of the first ground pattern 120 and the second ground pattern 140 in the planar direction.

[0059] For example, the first via structure 130, the first ground pattern 120, and the second ground pattern 140 can be formed as a substantially integral single member. For example, after forming a via hole penetrating the core layer 105 in the ground portion GP, ​​the first via structure 130, the first ground pattern 120, and the second ground pattern 140 can be integrally formed by forming and patterning a metal or alloy layer.

[0060] In some embodiments, the circuit board 100 may further include a protective layer 150 that covers the circuit wiring 110 and the first ground pattern 120. This may improve the impact resistance of the circuit wiring 110 and the driving stability of the circuit board 100.

[0061] For example, a coverlay film covering the circuit traces 110 can be provided as the protective layer 150 .

[0062] For example, the protective layer 150 can include substantially the same type of material as the core layer 105 .

[0063] In one embodiment, the protective layer 150 may include a cover window. The cover window may include, for example, glass (e.g., Ultra-Thin Glass (UTG)) or a transparent resin film. This may reduce or offset an external impact on the circuit wiring 110.

[0064] 3 is a schematic plan view showing a circuit board according to an exemplary embodiment, in which the core layer 105 is viewed from the direction of the second surface 105b.

[0065] Although the circuit board 100 is shown in an unbent shape in Figures 1 and 3 for convenience of explanation, the circuit board 100 of the present invention should be interpreted as being in a bent shape by a bend 104 as shown in Figure 2.

[0066] 3, the circuit board 100 may further include a second via structure 115 that penetrates the core layer 105 and is connected to an end of the circuit wiring 110. A signal transmitted to the circuit wiring 110 on the first surface 105a may be transmitted to the second surface 105b via the second via structure 115.

[0067] For example, the second via structure 115 can be disposed in the wiring portion CP.

[0068] For example, signals can be transmitted and received through the second via structure 115 from a control element connected to the second surface 105a.

[0069] For example, the circuit wiring 110 and the second via structure 115 can be formed as a substantially integral single member. For example, after forming a via hole penetrating the core layer 105, the circuit wiring 110 and the second via structure 115 can be integrally formed by forming and patterning a metal or alloy layer.

[0070] In some embodiments, a trench-shaped separation space SS may be formed between the circuit wiring 110 and the first ground pattern 120. This may reduce loss of signals transmitted through the circuit wiring 110 and shield noise.

[0071] For example, the shape of the isolation space SS can be changed by adjusting the patterning shape of the first ground pattern 120.

[0072] For example, the separation space SS may also be formed between the second via structure 115 and the first ground pattern 120 and / or between the second via structure 115 and the second ground pattern 140. For example, the second via structure 115 and the second ground pattern 140 may be separated by the separation space SS.

[0073] In some embodiments, the first ground pattern 120 can be disposed entirely on the first surface 105a of the core layer 105 in an area excluding the circuit wiring 110, the second via structure 115, and the separation space SS.

[0074] In some embodiments, the second ground pattern 140 may be disposed entirely on the second surface 105b of the core layer 105 in an area excluding the second via structure 115 and the separation space SS.

[0075] The circuit wiring 110, the first ground pattern 120, the second ground pattern 140, the first via structure 130, and / or the second via structure 115 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. These may be used alone or in combination of two or more.

[0076] In one embodiment, the circuit wiring 110, the first ground pattern 120, the second ground pattern 140, the first via structure 130 and / or the second via structure 115 may include silver (Ag) or a silver alloy (e.g., a silver-palladium-copper (APC) alloy), or copper (Cu) or a copper alloy (e.g., a copper-calcium (CuCa) alloy) to achieve low resistance and fine line width.

[0077] For example, the circuit wiring 110, the first ground pattern 120, the second ground pattern 140, the first via structure 130 and / or the second via structure 115 may be formed as a solid pattern to reduce power supply resistance and prevent signal loss.

[0078] 4 and 5 are schematic cross-sectional and plan views, respectively, of an antenna structure according to an exemplary embodiment.

[0079] 4 and 5, the antenna structure may include the aforementioned circuit board 100 and an antenna element 200 electrically connected to the circuit board 100.

[0080] For example, the antenna element 200 may include a dielectric layer 210 and an antenna unit 220 disposed on the dielectric layer 210 .

[0081] The dielectric layer 210 may include a transparent resin film containing 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.

[0082] In some embodiments, the dielectric layer 210 can include an adhesive film such as an optically clear adhesive (OCA), an optically clear resin (OCR), or the like.

[0083] In some embodiments, the dielectric layer 210 can include an inorganic insulating material such as silicon oxide, silicon nitride, silicon oxynitride, glass, or the like.

[0084] In one embodiment, the dielectric layer 210 may be provided in substantially a single layer.

[0085] In one embodiment, the dielectric layer 210 may include a multi-layer structure of at least two layers. For example, the dielectric layer 210 may include a base layer and a dielectric layer, and may also include an adhesive layer between the base layer and the dielectric layer.

[0086] The dielectric layer 210 forms an impedance or inductance to the antenna unit 220, thereby adjusting the frequency band in which the antenna structure can be driven or sensed. In some embodiments, the dielectric constant of the dielectric layer 210 can be adjusted to a range of about 1.5 to 12. If the dielectric constant exceeds about 12, the driving frequency may be too low, making it impossible to achieve driving in a high frequency band.

[0087] In one embodiment, an antenna ground (not shown) may be located below the bottom surface of the dielectric layer 210 .

[0088] In one embodiment, a conductive member of an image display device or a display panel to which the antenna structure is applied can be provided as the antenna ground.

[0089] For example, the conductive member may include electrodes or wiring such as gate electrodes, source / drain electrodes, pixel electrodes, common electrodes, data lines, and scan lines included in a thin film transistor (TFT) array panel.

[0090] In one embodiment, a metal member such as a stainless steel plate, a sensor member such as a digitizer, or a heat dissipation sheet disposed on the rear surface of the image display device can also be provided as the antenna ground.

[0091] In the exemplary embodiment, antenna unit 220 may include a radiator 222 and a transmission line 224 connected to radiator 222. Transmission line 224 may extend from radiator 222.

[0092] For example, the radiator 222 may be in the shape of a polygonal plate, and the transmission line 224 may have a width smaller than that of the radiator 222 and may be connected to one end or one side of the radiator 222. The radiator 222 and the transmission line 224 may be formed as a single member that is integrally connected to each other.

[0093] Depending on the shape / size of the radiator 222, the target resonant frequency of the antenna element 200 can be adjusted. In a non-limiting embodiment, the radiator 222 can be designed to be capable of radiating in high frequency / ultra high frequency bands such as 3G, 4G, 5G, or higher. For example, the radiator 222 can achieve radiation bands in the frequency bands of 0.5 GHz or higher, 1 GHz or higher, 10 GHz or higher, 20 GHz or higher, 30 GHz or higher, and 40 GHz or higher.

[0094] For example, the radiator 222 may provide a high frequency band radiating portion of the antenna unit 220. In one embodiment, the resonant frequency of the radiator 222 may be approximately 28 GHz or greater.

[0095] The transmission line may include a first transmission line 224a and a second transmission line 224b that are connected to the radiator 222 and face each other, thereby providing two polarization directions (dual polarization) with one radiator.

[0096] In some embodiments, the first transmission line 224a and the second transmission line 224b may each be connected to opposite sides of the lower surface of the radiator 222 (eg, to the vertices of the lower surface of the radiator 222 in FIG. 5).

[0097] The first transmission line 224a and the second transmission line 224b can extend in different directions from the radiator 222. This allows dual polarization characteristics to be achieved from a single radiator 222.

[0098] In some embodiments, the extension directions of the first transmission line 224a and the second transmission line 224b may form an angle of approximately 90°. For example, the extension directions of the first transmission line 224a and the second transmission line 224b may be perpendicular to each other. In one embodiment, the first transmission line 224a and the second transmission line 224b may extend toward the center of the radiator.

[0099] This allows the radiator 222 to be fed in two directions that are substantially perpendicular to each other via the first transmission line 224a and the second transmission line 224b. For example, both vertical and horizontal radiation from the radiator 222 can be achieved.

[0100] In some embodiments, the first transmission line 224a and the second transmission line 224b can be arranged symmetrically with respect to each other. For example, the first transmission line 224a and the second transmission line 224b can be arranged symmetrically with respect to a center line passing through the center of the radiator 222. This can make the signal strength in the two polarization directions substantially uniform.

[0101] In some embodiments, a signal pad 226 may be located at the end of the transmission line 224. The signal pad 226 may be a single member that is substantially integral with the transmission line 224. In this case, the end of the transmission line 224 may also be provided as the signal pad 226.

[0102] For example, the radiator 222 and the signal pad 226 may be electrically connected via a transmission line 224 .

[0103] The circuit board 100 and the antenna unit 220 can be electrically connected via the signal pad 226. This allows signal transmission and reception between the antenna driving integrated circuit (IC) chip of the circuit board 100 and the radiator 222.

[0104] In some embodiments, the antenna unit 220 may further include a ground pad 228 arranged around the signal pad 226 at a distance from the signal pad 226. The ground pad 228 may be electrically and physically separated from the transmission line 224 and the signal pad 226. In one embodiment, the pair of ground pads 228 may be arranged to face each other across the signal pad 226. This may reduce noise generation in the signal transmitted via the signal pad 226.

[0105] For example, the signal pad 226 and the ground pad 228 can be disposed in the bonding region BR where the antenna element 200 and the circuit board 100 are bonded. For example, the ground pad 228 can improve the bonding stability of the antenna element 200 and the circuit board 100 in the bonding region BR.

[0106] In one embodiment, the signal pad 226 and the ground pad 228 may include a solid structure, which can reduce the increase in resistance due to bonding at the connection between the antenna element 200 and the circuit board 100 and improve power supply efficiency.

[0107] In some embodiments, the circuit wiring 110 and the antenna element 200 can be connected on the first extension portion 102 of the circuit board 100. For example, the transmission line 224 and the circuit wiring 110 can be electrically connected.

[0108] For example, a conductive bonding structure such as ACF can be attached to the end of the signal pad 226 or the transmission line 224 in the bonding region BR. For example, a portion of the protective layer 150 (e.g., a coverlay film) can be removed to expose one end of the circuit wiring 110 disposed on the first surface 105a of the first extension portion 102. The exposed one end can be placed on the conductive bonding structure, and the circuit board 100 and the antenna element 200 can be connected by a heat treatment and pressure process.

[0109] This allows power supply and signal transmission / reception between the antenna element 200 and a device including the antenna structure.

[0110] For example, one end of the circuit trace 110 may be connected to the antenna element 200 and the other end may be connected to the second via structure 115 .

[0111] The antenna unit 220 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), calcium (Ca), or an alloy containing at least one of these, which may be used alone or in combination of two or more.

[0112] In one embodiment, the antenna unit 220 may include silver (Ag) or a silver alloy (e.g., a silver-palladium-copper (APC) alloy), or copper (Cu) or a copper alloy (e.g., a copper-calcium (CuCa) alloy) to achieve low resistance and fine linewidth.

[0113] In some embodiments, the antenna unit 220 may also include a transparent metal oxide such as indium tin oxide (ITO), indium zinc oxide (IZO), indium zinc tin oxide (ITZO), or zinc oxide (ZnOx).

[0114] In some embodiments, the antenna unit 220 may include a laminated structure of a transparent conductive oxide layer and a metal layer, for example, 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 to improve signal transmission speed, and the transparent conductive oxide layer can improve corrosion resistance and transparency.

[0115] The antenna unit 220 may include a blackening treatment, which reduces the reflectance on the surface of the antenna unit 220 and reduces the visibility of the pattern due to light reflection.

[0116] In one embodiment, the surface of a metal layer included in the antenna unit 220 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 antenna unit 220 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.

[0117] 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.

[0118] In some embodiments, the radiator 222 comprises a mesh structure, and at least a portion of the transmission line 224 and the signal pad 226 comprise a solid structure. In one embodiment, at least a portion of the radiator 222 may be formed with a mesh structure, and the remaining portion may be formed with a solid structure.

[0119] 6 and 7 are schematic cross-sectional and plan views, respectively, of an image display device according to an exemplary embodiment. FIG. 7 shows the front or window surface of image display device 300.

[0120] The front surface of the image display device 300 may include a display area (DA) 330 and a non-display area (NDA) 340. The non-display area 340 may correspond to a light blocking portion or a bezel portion of the image display device 300, for example.

[0121] The antenna element 200 according to the exemplary embodiment may be positioned towards the front of the image display device 300, for example, on the display panel 310.

[0122] In some embodiments, the antenna element 200 can be attached onto the display panel 310 in the form of a film.

[0123] In one embodiment, the antenna element 200 may be formed across the display area 330 and the non-display area 340 of the image display device 300. In one embodiment, the radiator 222 may at least partially overlap the display area 330.

[0124] As described above, the transmission line 224, the signal pad 226, and the ground pad 228 may overlap the non-display area 340 in the thickness direction. For example, a portion of the antenna unit 220 having a solid structure may overlap the non-display area 340.

[0125] In some embodiments, the antenna element 200 may be located at the center of one side of the image display device 300. This can prevent degradation of radiation performance on either side.

[0126] The antenna element 200 can be powered or driven through the circuit board 100 .

[0127] An antenna driving integrated circuit (IC) chip 250 may be mounted on the circuit board 100. As shown in Fig. 6, an intermediate circuit board 260, such as a rigid printed circuit board, may be disposed between the circuit board 100 and the antenna driving IC chip 250. In one embodiment, the antenna driving IC chip 250 may be mounted directly on the circuit board 100.

[0128] Referring to FIG. 6, an image display device 300 may include a display panel 310 and the above-described antenna element 200 disposed on the display panel 310 .

[0129] According to an exemplary embodiment, an optical layer 320 may further be included on the display panel 310. For example, the optical layer 320 may be a polarizing layer including a polarizer or a polarizing plate.

[0130] The circuit board 100 (e.g., a flexible printed circuit board) can be bent, for example, along the side bending profile of the display panel 310 and placed on the back side of the image display device 300, and can extend toward an intermediate circuit board 260 (e.g., a main board) on which the antenna driving IC chip 250 is mounted.

[0131] The circuit board 100 and the intermediate circuit board 260 are interconnected by bonding or via a connector, and the antenna driving IC chip 250 can feed power to the antenna element 200 and control the antenna driving.

[0132] In some embodiments, the antenna element 200 is disposed on the display panel 310, and the circuit board 100 is bent by the bending portion 104 to extend below the display panel 310. This can improve the space efficiency of the image display device 300. In addition, the above-described structure of the circuit board 100 can suppress the generation of unnecessary electric fields due to the bending, thereby improving the antenna gain.

[0133] For example, the circuit board 100 and the antenna element 200 can be connected on the first extension portion 102, and the circuit board 100 and the antenna driving IC chip 250 can be connected on the second extension portion 106. This allows the antenna driving IC chip 250 to feed power to the antenna unit 220 and transmit and receive signals.

[0134] Examples are presented below to aid 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 will be apparent to those skilled in the art that various changes and modifications to the examples are possible within the scope and technical spirit of the present invention, and it is natural that such changes and modifications also fall within the scope of the appended claims.

[0135] Standard example (non-bending) An antenna structure was fabricated on the COP dielectric layer by patterning a conductive line containing copper (Cu) and a via structure penetrating the COP dielectric layer as shown in FIG. The conductive lines had a line width of 2 μm and a thickness of 0.5 μm. The target resonant frequency of the antenna unit was adjusted to approximately the 28 GHz band.

[0136] Example As shown in FIG. 5, an antenna structure manufactured in the same manner as the reference example, except that the first via structure was not formed in the wiring portion, was used as a spare antenna structure. The circuit board of the preliminary antenna structure was bent at the bending portion to manufacture the antenna structure.

[0137] Comparative Example An antenna structure was manufactured in the same manner as in the example, except that an antenna structure (having a first via structure formed in the wiring portion) manufactured in the same manner as in the reference example was used as a spare antenna structure.

[0138] Experimental example The electric field formation and antenna peak gain according to frequency of the antenna structures manufactured in the example and comparative example were measured using an HFSS simulator (manufactured by Ansys).

[0139] In the examples and comparative examples, power was supplied to four of the eight circuit wirings. The powered circuit wirings and the non-powered circuit wirings were arranged alternately.

[0140] FIG. 9 is an image showing electric field generation diagrams of the antenna structures of the example and the comparative example.

[0141] Referring to FIG. 9, in the example, the generation of an unnecessary electric field around the circuit wiring was suppressed compared to the comparative example.

[0142] Specifically, in the example, the electric field was concentrated on the circuit wiring, suppressing the formation of an electric field in the first ground pattern, whereas in the comparative example, an unnecessary electric field was formed in the first ground pattern, reducing the antenna gain.

[0143] FIG. 10 is a graph showing the antenna peak gain as a function of frequency for the antenna structures of the reference example, the working example, and the comparative example.

[0144] Referring to FIG. 10, in the example in which the first via structure was not disposed in the wiring portion, the antenna peak gain in the target frequency band (rectangular box area) was improved compared to the comparative example.

[0145] In the comparative example, an unnecessary electric field was generated due to bending of the circuit board, and the antenna peak gain was reduced compared to when the circuit board was not bent.

[0146] In the example in which the first via structure was not placed in the wiring section but only in the ground section, the antenna peak gain measured was substantially the same as that of the reference example in which the circuit board was not bent, even though the circuit board was bent.

Claims

1. a core layer including a wiring portion and a ground portion disposed around the wiring portion; a circuit wiring extending on the wiring portion; a first ground pattern disposed around the circuit wiring and spaced apart from the circuit wiring; a first via structure disposed in the ground portion, penetrating the core layer, and not disposed in the wiring portion.

2. The circuit board according to claim 1 , wherein the circuit wiring is not disposed on the ground portion.

3. the circuit wiring includes a plurality of circuit wirings extending on the wiring portion; 2. The circuit board according to claim 1, wherein the distance between the ground portion and an outermost circuit wiring of the plurality of circuit wirings is three times or more the line width of the circuit wiring.

4. the core layer includes a first surface and a second surface facing each other, the circuit wiring and the first ground pattern are disposed on the first surface, The circuit board according to claim 1 , further comprising a second ground pattern disposed on the second surface.

5. The circuit board according to claim 4 , wherein the first via structure electrically connects the first ground pattern and the second ground pattern.

6. The circuit board according to claim 1 , wherein the first via structures include a plurality of first via structures each penetrating the core layer in the ground portion.

7. The circuit board of claim 6 , wherein the plurality of first via structures include outer via structures arranged continuously along an outermost portion of the circuit board.

8. The circuit board of claim 7 , wherein the plurality of first via structures further includes an inner via structure other than the outer via structure.

9. The circuit board according to claim 8 , wherein the distance between adjacent internal via structures is greater than the distance between adjacent external via structures.

10. The circuit board according to claim 1 , wherein the core layer includes a first extension, a bent portion connected to the first extension, and a second extension connected to the bent portion and facing the first extension.

11. The circuit board according to claim 1 , further comprising a second via structure that penetrates the core layer and is connected to an end of the circuit wiring.

12. The circuit board according to claim 1 , further comprising a protective layer covering the circuit wiring and the first ground pattern.

13. The circuit board according to claim 1; an antenna element electrically connected to the circuit board.

14. The antenna structure according to claim 13 , wherein the antenna element includes a radiator and a transmission line connected to the radiator, the transmission line being electrically connected to the circuit wiring.

15. A display panel; An image display device comprising: an antenna structure according to claim 13 disposed on the display panel.

Images