Antenna device and image display device including the same

Abstract

An antenna element according to an exemplary embodiment of the present invention comprises a dielectric layer and an antenna unit disposed on the dielectric layer, the antenna unit comprising a metal layer and a metal oxide layer, wherein the thickness of the metal oxide layer is 60 to 100 nm. Accordingly, external visibility can be suppressed while maintaining the low resistance of the antenna unit.

Description

Technology Field

[0001] The present invention relates to an antenna element and an image display device including the same. More specifically, the invention relates to an antenna element including a dielectric layer and an antenna unit and an image display device including the same. Background Technology

[0002] With the recent development of the information society, wireless communication technologies such as Wi-Fi and Bluetooth are being combined with image display devices and implemented, for example, in the form of smartphones. In this case, an antenna can be combined with the image display device to perform communication functions.

[0003] As mobile communication technology evolves recently, for example, an antenna for performing communication in the high frequency or ultra-high frequency band needs to be coupled to the image display device.

[0004] However, as part of the antenna's metal pattern overlaps with the display portion of the image display device, it may be visible to the user of the image display device. Consequently, the color quality and image quality of the image display device may be degraded.

[0005] Therefore, it is necessary to design an antenna element in which the metal pattern included in the antenna is not visible while maintaining or improving the radiation characteristics of the antenna.

[0006] For example, Korean Published Patent No. 2003-0095557 discloses an antenna structure embedded in a portable terminal, but does not disclose a material that takes into account radiation characteristics and visibility as described above. Prior art literature

[0007] Korean Patent Publication No. 2013-0095451 The problem to be solved

[0008] One objective of the present invention is to provide an antenna element that is not easily visible to the user.

[0009] One objective of the present invention is to provide an image display device including an antenna element that is not easily visible to the user. means of solving the problem

[0010] 1. A dielectric layer; and an antenna element comprising an antenna unit disposed on the dielectric layer, the antenna unit comprising a metal layer and a metal oxide layer, wherein the thickness of the metal oxide layer is 60 to 100 nm.

[0011] 2. An antenna element according to 1 above, wherein the thickness of the metal layer is 200 to 1,000 nm.

[0012] 3. An antenna element in which the a* and b* values ​​in the International Commission on Illumination (CIE) L*a*b* color system are each -1.0 to 0.5.

[0013] 4. An antenna element according to 3, wherein the a* value and the b* value are each -0.6 to 0.3.

[0014] 5. An antenna element according to 1 above, wherein the metal layer and the metal oxide layer are sequentially stacked on the dielectric layer, and a transparent conductive oxide layer is further disposed on the metal oxide layer.

[0015] 6. An antenna element according to 1 above, wherein a transparent conductive oxide layer is further disposed on the dielectric layer, and the metal layer and the metal oxide layer are sequentially disposed on the transparent conductive oxide layer.

[0016] 7. An antenna element according to 6, wherein the transparent conductive oxide layer is further disposed on the metal oxide layer.

[0017] 8. An antenna element according to 1 above, wherein the metal oxide layer and the metal layer are sequentially stacked on the dielectric layer, and a transparent conductive oxide layer is further disposed on the metal layer.

[0018] 9. An antenna element according to 1 above, wherein the antenna unit comprises a radiator, a transmission line extending from the radiator, a signal pad connected to the end of the transmission line, and a pair of ground pads spaced apart from the transmission line and the signal pad and positioned with the signal pad in between.

[0019] 10. An antenna element in which the radiator and the transmission line include a mesh structure, wherein the above 9.

[0020] 11. An antenna element according to 10, wherein the mesh structure comprises a plurality of intersecting conductive lines, and the width of each of the conductive lines is 0.5 to 10 μm.

[0021] 12. An antenna element according to 9, wherein the signal pad and the ground pad include a solid pattern.

[0022] 13. An antenna element in which the metal oxide layer is included only in the radiator and the transmission line in the above 9.

[0023] 14. An antenna element according to 9, wherein the metal oxide layer is included in the radiator, the transmission line, the signal pad, and the ground pad.

[0024] 15. A display panel; an image display device comprising the above-described antenna element disposed on the display panel.

[0025] 16. An image display device according to 15, further comprising an optical layer disposed on the display panel and a cover window disposed on the antenna element, wherein the antenna element is disposed between the optical layer and the cover window. Effects of the invention

[0026] According to embodiments of the present invention, an antenna unit may include a metal layer and a metal oxide layer formed on the metal layer with a thickness of 60 to 100 nm. In this case, the metal oxide layer can reduce the reflectivity on the surface of the antenna unit, thereby reducing pattern visibility due to light reflection. Accordingly, external visibility of the antenna unit can be suppressed, and the display quality of the image display device can be improved.

[0027] In addition, when the metal oxide layer is formed with the above thickness, for example, the external visibility suppression effect described above can be achieved while maintaining the low resistance characteristics of the antenna unit.

[0028] According to some embodiments, the thickness of the metal layer may be 200 to 1,000 nm. In this case, color matching with the metal oxide layer is improved, and visibility may be further reduced.

[0029] According to some embodiments, the a* and b* values ​​in the CIE L*a*b* color system may each be -0.6 to 0.5. In this case, the antenna unit may be prevented from being visible as red or yellow. Accordingly, external visibility of the antenna unit may be further prevented. Brief explanation of the drawing

[0030] FIGS. 1 and FIGS. 2 are schematic cross-sectional views showing antenna elements according to exemplary embodiments, respectively. FIG. 3 is a schematic plan view showing an antenna element according to exemplary embodiments. FIG. 4 is a schematic plan view showing an antenna element and a circuit board according to exemplary embodiments. FIG. 5 is a schematic cross-sectional view showing an image display device according to exemplary embodiments. FIGS. 6 and FIGS. 7 are schematic cross-sectional and plan views, respectively, for illustrating an image display device according to exemplary embodiments. Figure 8 shows the results of the color and pattern visibility evaluation of antenna elements according to the examples and comparative examples. Figure 9 is a graph showing the a* and b* values ​​of the CIE L*a*b* color system of antenna elements according to the examples and comparative examples. Specific details for implementing the invention

[0031] Embodiments of the present invention provide an antenna element comprising a dielectric layer and an antenna unit. Additionally, an image display device comprising the antenna element is provided.

[0032] Embodiments of the present invention will be described in more detail below with reference to the drawings. However, the following drawings attached to this specification are intended to illustrate preferred embodiments of the present invention and serve to further enhance understanding of the technical concept of the present invention together with the aforementioned description; therefore, the present invention should not be interpreted as being limited only to the matters described in such drawings.

[0033] FIGS. 1 and FIGS. 2 are schematic cross-sectional views showing antenna elements according to exemplary embodiments.

[0034] Referring to FIGS. 1 and 2, the antenna element (100) may include a dielectric layer (110) and an antenna unit (120) disposed on the dielectric layer (110).

[0035] The dielectric layer (110) is a polyester resin such as polyethylene terephthalate, polyethylene isophthalate, polyethylene naphthalate, or polybutylene terephthalate; a cellulose resin such as diacetylcellulose or triacetylcellulose; a polycarbonate resin; an acrylic resin such as polymethyl (meth)acrylate or polyethyl (meth)acrylate; a styrene resin such as polystyrene or acrylonitrile-styrene copolymer; a polyolefin resin such as polyethylene, polypropylene, a polyolefin having a cyclo- or norbornene structure, or an ethylene-propylene copolymer; a vinyl chloride resin; an amide resin such as nylon or aromatic polyamide; an imide resin; a polyethersulfone resin; a sulfone resin; a polyetheretherketone resin; a polyphenylene sulfide resin; a vinyl alcohol resin; a vinylidene chloride resin; a vinyl butyral resin; an allylate resin; It may include a transparent resin film comprising a polyoxymethylene resin; an epoxy resin; a urethane or acrylicurethane resin; a silicone resin, etc. These may be used individually or in combination of two or more.

[0036] The dielectric layer (110) may include an adhesive material such as an optically clear adhesive (OCA) or an optically clear resin (OCR). In some embodiments, the dielectric layer (110) may include an inorganic insulating material such as silicon oxide, silicon nitride, silicon oxynitride, glass, etc.

[0037] In some embodiments, the dielectric constant of the dielectric layer (110) can be adjusted to a range of about 1.5 to 12. If the dielectric constant exceeds about 12, the driving frequency is reduced excessively, and driving in the desired high frequency band may not be achieved.

[0038] An antenna unit (120) may be formed on the upper surface of the dielectric layer (110). For example, a plurality of antenna units (120) may be arranged in an array form along the width direction of the dielectric layer (110) or the antenna element (100) to form a row of antenna units.

[0039] In exemplary embodiments, the antenna unit (120) may include a metal layer (130) and a metal oxide layer (140).

[0040] For example, the metal layer (130) may comprise 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.

[0041] In one embodiment, the metal layer (130) 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. For example, the metal layer (130) may include copper (Cu).

[0042] In exemplary embodiments, the metal oxide layer (140) may be an oxide of a metal or alloy that may be included in the metal layer (130) described above. For example, the metal oxide layer (140) may be formed by converting the surface of the metal layer (130) into a metal oxide.

[0043] For example, the metal oxide layer (140) may be provided as a blackening treatment portion. Accordingly, the metal oxide layer (140) can reduce the reflectivity on the surface of the antenna unit (120) to reduce pattern visibility due to light reflection.

[0044] In exemplary embodiments, the thickness of the metal oxide layer (140) may be 60 to 100 nm.

[0045] For example, if the thickness of the metal oxide layer (140) is less than 60 nm, the reflectance of the antenna unit (120) increases in the wavelength range of the red region (e.g., 630 to 740 nm wavelength range), and a reddish phenomenon may occur. Accordingly, the surface of the antenna unit (120) may be seen as red by the user, and the color and brightness of the image display device described later may be reduced.

[0046] If the thickness of the metal oxide layer (140) exceeds 100 nm, for example, the reflectance of the antenna unit (120) increases in the wavelength range of the yellow region (e.g., 570 to 590 nm wavelength range), and a yellowish phenomenon may occur. Accordingly, the surface of the antenna unit (120) may be perceived as yellow by the user, and the color and brightness of the image display device described later may be reduced.

[0047] In addition, when the thickness of the metal oxide layer (140) is 60 to 100 nm, for example, the low resistance characteristics of the antenna unit (120) can be maintained. Accordingly, an antenna element (100) with excellent signal efficiency and reduced visibility can be realized.

[0048] For example, the metal oxide layer (140) can cover the surface of the metal layer (130) to improve the corrosion resistance of the antenna unit (120). Accordingly, the driving reliability of the antenna element (100) can be improved.

[0049] In some embodiments, the thickness of the metal layer (130) may be 200 to 1,000 nm. In this case, the color matching between the metal oxide layer (140) and the metal layer (130) described above can be improved while maintaining a thin thickness of the antenna element (100). Accordingly, the visibility of the entire antenna unit (120) can be reduced while maintaining or improving space efficiency.

[0050] In some embodiments, the antenna element (100) may have a* value and a* value of -1.0 to 0.5 in the International Commission on Illumination (CIE) L*a*b* color system. The a* value and b* value may preferably be -0.6 to 0.3, and more preferably -0.4 to 0.25.

[0051] The term "CIE L*a*b* color system" as used in this specification refers to the color system standardized and recommended by the CIE in 1976 and can be interpreted in the sense commonly used in the relevant technical field.

[0052] In the above color system, for example, as the a* value increases in the positive range, it approaches red, and as it decreases in the negative range, it approaches green.

[0053] In the above color system, for example, as the b* value increases in the positive range, it approaches yellow, and as it decreases in the negative range, it approaches blue.

[0054] In the above color system, the L* value may represent, for example, reflectance or lightness.

[0055] When the a* value and the b* value in the above color system are each within the ranges described above, excessive reddening or yellowing of the antenna unit (120) can be suppressed. Specifically, when the a* value and the b* value satisfy the above ranges, reddening when the a* value exceeds 0.5 or yellowing when the b* value exceeds 0.5 can be prevented. In addition, it can be prevented that the antenna unit is seen as green or blue when the a* value and the b* value decrease excessively in the negative range (e.g., less than -0.6 each). Accordingly, the visibility of the antenna unit (120) is reduced and the screen display quality of the image display device can be improved.

[0056] As shown in FIG. 2, the metal layer (130) and the metal oxide layer (140) are sequentially stacked on the dielectric layer (110), and according to some embodiments, a transparent conductive oxide layer (150) may be further disposed on the metal oxide layer (140).

[0057] In this case, corrosion of the metal layer (130) can be further suppressed, thereby further improving the corrosion resistance of the antenna unit (120). Accordingly, the driving reliability and stability of the antenna element (100) can be further improved.

[0058] For example, the transparent conductive oxide layer (150) may include at least one of indium tin oxide (ITO), indium zinc oxide (IZO), indium zinc tin oxide (ITZO), and zinc oxide (ZnOx).

[0059] In some embodiments, the antenna unit (120) may include a stacked structure of a metal layer (130), a metal oxide layer (140), and a transparent conductive oxide layer (150).

[0060] For example, it may have a three-layer structure of the metal layer (130)-metal oxide layer (140)-transparent conductive oxide layer (150) described above, metal oxide layer (140)-metal layer (130)-transparent conductive oxide layer (150), or transparent conductive oxide layer (150)-metal layer (130)-metal oxide layer (140), or a four-layer structure of transparent conductive oxide layer (150)-metal layer (130)-metal oxide layer (140)-transparent conductive oxide layer (150).

[0061] When a transparent conductive oxide layer (150) is directly laminated onto a dielectric layer (110), for example, the adhesion to the dielectric layer of an antenna unit (120) can be improved. Accordingly, the driving stability and reliability of the antenna element (100) can be improved.

[0062] FIG. 3 is a schematic plan view showing an antenna element according to exemplary embodiments.

[0063] Specifically, FIG. 3 is a schematic plan view showing an antenna element (100) according to exemplary embodiments mounted on an image display device (300) to be described later. For example, the antenna element (100) may be formed across a display area (330) and a non-display area (340) to be described later of the image display device (300).

[0064] Referring to FIG. 3, the antenna unit (120) may include a radiator (122) and a transmission line (124). The radiator (122) may have a polygonal plate shape, for example, and the transmission line (124) may extend from one side of the radiator (122). The transmission line (124) may be formed as a single member substantially integral with the radiator (122) and may have a narrower width than the radiator (122).

[0065] The antenna unit (120) may further include a signal pad (126). The signal pad (126) may be connected to the end portion of the transmission line (124). In one embodiment, the signal pad (126) is provided as substantially integral with the transmission line (124), and the end portion of the transmission line (124) may be provided as the signal pad (126).

[0066] According to some embodiments, a ground pad (128) may be placed around the signal pad (126). For example, a pair of ground pads (128) may be placed facing each other with the signal pad (126) in between. The ground pad (128) may be electrically and physically separated from the transmission line (124) and the signal pad (126).

[0067] The antenna unit (120) or radiator (122) may be designed to have a resonant frequency in a high frequency or ultra-high frequency band, for example, 3G, 4G, 5G or higher. For example, the resonant frequency of the antenna unit (120) may be in the range of about 20 to 45 GHz.

[0068] In some embodiments, radiators (122) having different sizes may be arranged on the antenna dielectric layer (110). In this case, the antenna element (100) may be provided as a multi-radiating or multi-band antenna that radiates in a plurality of resonant frequency bands.

[0069] In some embodiments, the radiator (122) and the transmission line (124) may include a mesh structure to improve transmittance. In this case, a dummy mesh pattern (not shown) may be formed around the radiator (122) and the transmission line (124).

[0070] In some embodiments, the mesh structure includes a plurality of intersecting conductive lines, and the line width of each conductive line may be 0.5 to 10 μm, preferably 2.0 to 4.0 μm. In this case, antenna signal loss can be suppressed while sufficiently securing the aperture ratio of the antenna unit (120). Accordingly, antenna performance can be maintained or improved while preventing visibility of the antenna element (100) together with the metal oxide layer (140) described above.

[0071] The signal pad (126) and ground pad (128) may be formed as a solid pattern made of the metal or alloy described above, taking into account the reduction of power supply resistance, noise absorption efficiency, and improvement of horizontal radiation characteristics.

[0072] In one embodiment, the radiator (122) has a mesh structure, and at least a portion of the transmission line (124) may include a solid metal pattern.

[0073] The radiator (122) is positioned within the display area of ​​the image display device, and the signal pad (126) and ground pad (128) may be positioned within the non-display area or bezel area of ​​the image display device. The at least part of the transmission line (124) may also be positioned within the non-display area or bezel area.

[0074] In some embodiments, the metal oxide layer (140) may be included only in the radiator (122) and transmission line (124) and not in the signal pad (126) and ground pad (128). Accordingly, the visibility of the radiator (122) and transmission line (124) placed on the display area of ​​the image display device can be suppressed while reducing process costs.

[0075] In some embodiments, the metal oxide layer (140) may be included in the radiator (122), transmission line (124), signal pad (126), and ground pad (128). Accordingly, the process for forming the antenna unit (120) can be simplified, while the visibility of the antenna element (100) can be suppressed.

[0076] FIG. 4 is a schematic plan view showing an antenna element and a circuit board according to exemplary embodiments.

[0077] Referring to FIG. 4, the antenna element (100) can be electrically connected to a flexible printed circuit board (200).

[0078] A flexible printed circuit board (200) may include a core layer (210) and signal wiring (220) formed on the surface of the core layer (210).

[0079] In some embodiments, the dielectric layer (110) may be provided as a flexible printed circuit board (200). In this case, the flexible printed circuit board (200) (e.g., the core layer (210) of the flexible printed circuit board (200)) may be provided as a substantially integral member with the dielectric layer (110). Additionally, the signal wiring (220) described below may be directly connected to the transmission line (124), and the signal pad (126) may be omitted.

[0080] The core layer (210) may include a flexible resin such as, for example, polyimide resin, MPI (Modified Polyimide), epoxy resin, polyester, cycloolefin polymer (COP), liquid crystal polymer (LCP), etc. The core layer (210) may include an internal insulating layer included in the circuit board (200).

[0081] The signal wiring (220) may be provided as a feed line, for example. The signal wiring (220) may be arranged on one side of the core layer (210) (for example, the surface facing the antenna unit (120)).

[0082] For example, the flexible printed circuit board (200) may further include a coverlay film formed on one side of the core layer (210) and covering the signal wiring.

[0083] The signal wires (220) can be connected or bonded to the signal pads (126) of the antenna units (120). For example, one end of the signal wires (220) can be exposed by partially removing the coverlay film of the flexible printed circuit board (200). The exposed end of the signal wires (220) can be bonded to the signal pad (126).

[0084] For example, a conductive bonding structure, such as an anisotropic conductive film (ACF), can be attached to signal pads (126), and then a bonding region (BR) of a flexible printed circuit board (200) where the signal wiring (220) ends are located can be placed on the conductive bonding structure. Subsequently, the bonding region (BR) of the flexible printed circuit board (200) can be attached to an antenna element (100) through a heat treatment / pressure process, and the signal wiring (220) can be electrically connected to each signal pad (126).

[0085] As illustrated in FIG. 4, signal wires (220) can each be independently connected or bonded to each of the signal pads (126) of the antenna units (120). In this case, feed and control signals can be independently supplied from the antenna driving integrated circuit (IC) chip (260) to each antenna unit (120).

[0086] In some embodiments, a predetermined number of antenna units (120) may be coupled through signal wiring (220).

[0087] In exemplary embodiments, an intermediate circuit board (250) may be arranged to be physically and electrically connected to a flexible printed circuit board (200). For example, an antenna driving IC chip (260) may be mounted on the intermediate circuit board (250), for example, via surface mount technology (SMT).

[0088] The term "intermediate circuit board" used in this application may comprehensively refer to a connector, circuit structure, or circuit board located between a flexible printed circuit board (200) and an antenna driving IC chip (260).

[0089] For example, the intermediate circuit board (250) may include a main board of an image display device, a rigid printed circuit board, and various antenna package boards. Additionally, the intermediate circuit board (250) may include a main board with a connector mounted thereon, a rigid printed circuit board, and various antenna packages.

[0090] When the intermediate circuit board (250) is a rigid printed circuit board, for example, the intermediate circuit board (250) may have higher strength or lower flexibility than the flexible printed circuit board (200). Accordingly, the mounting stability of the antenna driving IC chip (260) can be improved. For example, when the intermediate circuit board (250) is a rigid printed circuit board, it may include a resin layer (e.g., epoxy resin) impregnated with an inorganic material such as glass fiber, such as prepreg, as a base insulating layer or core layer, and may include signal wiring distributed on the surface and inside the base insulating layer.

[0091] Feed and driving signals can be applied from the antenna driving IC chip (260) to the antenna units (120) through the signal wires (220). For example, the flexible printed circuit board (200) may further include a circuit or contact that electrically connects the antenna driving IC chip (260) and the signal wires (220).

[0092] FIG. 5 is a schematic cross-sectional view showing an image display device according to exemplary embodiments.

[0093] Referring to FIG. 5, the image display device (300) may include a display panel (305) and the above-described antenna element (100) disposed on the display panel (305).

[0094] In exemplary embodiments, an optical layer (310) may be further included on the display panel (305), and a cover window (320) may be disposed on the antenna element (100).

[0095] For example, the optical layer (310) may be a polarization layer including a polarizer or a polarizing plate.

[0096] The cover window (320) may include, for example, glass (for example, ultra-thin glass (UTG) or a transparent resin film. Accordingly, external impact applied to the antenna element (100) may be reduced or offset.

[0097] For example, the antenna element (100) may be placed between the optical layer (310) and the cover window (320). In this case, the dielectric layer (110) and the optical layer (310) placed below the antenna unit (120) may be provided together as the dielectric layer of the antenna unit (120). Accordingly, the antenna performance of the antenna element (100) can be sufficiently secured by ensuring an appropriate dielectric constant.

[0098] In addition, even if the antenna element (100) is positioned above the optical layer (310) with respect to the viewing surface, external visibility of the antenna unit can be suppressed by the metal oxide layer (140) described above. Accordingly, the display quality of the image display device can be improved while securing a sufficient antenna dielectric constant.

[0099] For example, the optical layer (310) and the antenna element (100) can be laminated through the first adhesive layer (161), and the antenna element (100) and the cover window (320) can be laminated through the second adhesive layer (163).

[0100] The first adhesive layer (161) and the second adhesive layer (163) may include adhesive materials such as, for example, an optically transparent adhesive (OCA), an optically transparent resin (OCR), etc.

[0101] FIGS. 6 and FIGS. 7 are schematic cross-sectional and plan views, respectively, for illustrating an image display device according to exemplary embodiments.

[0102] Referring to FIGS. 6 and 7, the image display device (300) may be implemented in the form of, for example, a smartphone, and FIG. 7 illustrates the front or window surface of the image display device (300). The front of the image display device (300) may include a display area (330) and a peripheral area (340). The peripheral area (340) may correspond, for example, to a light-blocking portion or a bezel portion of the image display device.

[0103] The antenna element (100) included in the antenna package described above may be positioned toward the front of the image display device (300), for example, on a display panel (305). In one embodiment, the radiators (122) may overlap at least partially with the display area (330).

[0104] In this case, the radiator (122) may include a mesh structure and prevent a decrease in transmittance caused by the radiator (122). The pads (126, 128) included in the antenna unit (120) may be formed as a solid metal pattern and, in this case, may be placed in a surrounding area (340) to prevent a decrease in image quality.

[0105] In some embodiments, the flexible printed circuit board (200) may be bent along the side curve profile of, for example, the display panel (305) and extended toward an intermediate circuit board (250) (e.g., main board) on which an antenna driving IC chip (260) is mounted, which is positioned on the back of the image display device (300).

[0106] The flexible printed circuit board (200) and the intermediate circuit board (250) are bonded or interconnected through a connector so that power supply to the antenna element (100) and antenna driving control by the antenna driving IC chip (260) can be implemented.

[0107] In the following, experimental examples including specific embodiments and comparative examples are presented to aid in understanding the present invention; however, these are merely illustrative of the invention and do not limit the appended claims. It is obvious to those skilled in the art that various changes and modifications to the embodiments are possible within the scope and spirit of the present invention, and that such variations and modifications fall within the scope of the appended claims.

[0108] Example 1

[0109] A copper (Cu) layer with a thickness of 500 nm (e.g., corresponding to a metal layer (130)) was formed on a polyethylene terephthalate (PET) layer by sputtering (90°C, 23 kW conditions).

[0110] A copper oxide (CuO) layer with a thickness of 61 nm (e.g., corresponding to a metal oxide layer (140)) was formed on the copper layer using a sputtering method under the same conditions.

[0111] An IZO layer (e.g., a transparent conductive oxide layer (150)) was formed on the copper oxide layer using a sputtering method under the same conditions.

[0112] After that, the copper layer, copper oxide layer, and IZO layer formed through a photolithography process were etched to manufacture an antenna unit including a radiator and transmission line having a mesh structure, and a signal pad and ground pad having a solid pattern.

[0113] At this time, the line width of the conductive lines included in the mesh structure was formed to be 2.5㎛.

[0114] An image display device was manufactured by stacking a polarizing layer on a display panel of a smartphone and stacking an antenna element including the antenna unit and a PET layer on the polarizing layer.

[0115] At this time, glass was laminated onto the antenna element as a cover window. In addition, the polarization layer and the antenna element, and the antenna element and the cover window were each laminated through an OCA point adhesive layer.

[0116] In the CIE L*a*b* color system of the formed antenna element, the a* and b* values ​​were measured and calculated as 0.05 and -0.55, respectively.

[0117] Specifically, the a* and b* values ​​of the antenna element were measured using the SCI mode of the CM-3600d spectrophotometer (manufactured by KONIKA MINOLTA).

[0118] Examples 2 to 10

[0119] An antenna unit and an image display device were manufactured in the same manner as in Example 1, except that the antenna unit was manufactured such that the thickness of the copper layer, the thickness of the copper oxide layer, the line widths of the conductive lines, and the a* and b* values ​​in the CIE L*a*b* color system were as listed in Table 1 below.

[0120] Example 11

[0121] An antenna unit and an image display device were manufactured in the same manner as in Example 4, except that an IZO layer was not formed on the copper oxide layer.

[0122] Comparative Examples 1 to 5

[0123] An antenna unit and an image display device were manufactured in the same manner as in Example 1, except that the thickness of the copper oxide layer and the a* and b* values ​​in the CIE L*a*b* color system were manufactured as described in Table 1 below.

[0124] Comparative Example 6

[0125] An antenna unit and an image display device were manufactured in the same manner as in Example 1, except that a copper oxide layer and an IZO layer were not formed.

[0126] division Copper oxide layer thickness (nm) Copper layer thickness (nm) Challenge line width (㎛) Whether an IZO layer is formed CIE L*a*b* color system a* b* Example 1 61 500 2.5 O 0.05 -0.55 Example 2 68 500 2.5 O 0.14 -0.46 Example 3 76 500 2.5 O -0.06 -0.46 Example 4 84 500 2.5 O -0.12 -0.33 Example 5 92 500 2.5 O -0.09 -0.21 Example 6 100 500 2.5 O -0.11 -0.07 Example 7 84 190 2.5 O -0.13 -0.31 Example 8 84 1,020 2.5 O -0.14 -0.32 Example 9 84 500 0.4 O -0.11 -0.33 Example 10 84 500 10.2 O -0.13 -0.30 Example 11 84 500 2.5 Χ -0.10 -0.31 Comparative Example 1 40 500 2.5 O 1.20 0.16 Comparative Example 2 48 500 2.5 O 0.66 -0.27 Comparative Example 3 56 500 2.5 O 0.52 -0.52 Comparative Example 4 108 500 2.5 O -0.10 0.54 Comparative Example 5 116 500 2.5 O -0.11 0.85 Comparative Example 6 - 500 2.5 Χ - -

[0127] Experimental Example

[0128] (1) Visibility evaluation

[0129] In the image display device manufactured according to the above-described embodiments and comparative examples, the portion on which the antenna unit is mounted was visually observed to confirm whether the antenna unit is visible.

[0130] O: Clearly acknowledged

[0131] △: Indistinctly recognized from a specific direction

[0132] Χ: Not recognized in all directions

[0133] (2) Measurement of surface resistance (Rs, ohm / sq)

[0134] The antenna units manufactured according to the above-described embodiments and comparative examples were measured using a sheet resistance measuring instrument, the Resist Test RT-80.

[0135] Specifically, three probes within the RT-80 were in contact with one side of the antenna unit to take measurements, five points were measured within a 100mm x 100mm area, and a total of 150 points were measured per plate to measure the total surface resistance of the antenna unit.

[0136] (3) Corrosion resistance evaluation

[0137] An antenna unit manufactured according to the above-described examples and comparative examples was left in an environment of 85°C and 85% relative humidity, and the time at which corrosion was first observed was measured.

[0138] division Whether or not it is a poet Sheet resistance (ohm / sq) Corrosion resistance (hr) Example 1 Χ 0.042 503 Example 2 Χ 0.041 505 Example 3 Χ 0.041 501 Example 4 Χ 0.042 510 Example 5 Χ 0.042 506 Example 6 Χ 0.041 507 Example 7 △ 0.042 502 Example 8 △ 0.042 503 Example 9 Χ 0.045 505 Example 10 △ 0.041 504 Example 11 Χ 0.042 253 Comparative Example 1 O 0.042 509 Comparative Example 2 O 0.042 505 Comparative Example 3 O 0.041 506 Comparative Example 4 O 0.042 502 Comparative Example 5 O 0.042 498 Comparative Example 6 O 0.041 110

[0139] Referring to Table 2, the embodiments in which a metal oxide layer is laminated on a metal layer with a thickness of 60 to 100 nm maintained overall low resistance characteristics compared to comparative examples that did not satisfy the thickness range, while suppressing external visibility of the antenna unit.

[0140] However, Example 7, in which the thickness of the metal layer is less than 200 nm, and Example 8, in which the thickness of the metal layer exceeds 1,000 nm, had reduced color matching with the metal oxide layer and were indistinctly visible to the user from a specific direction.

[0141] In addition, Example 9, in which the line width of the conductive lines of the mesh structure is less than 0.5 μm, showed a decrease in sheet resistance compared to other examples due to the relatively narrow line width.

[0142] Example 10, in which the line width of the challenge lines exceeds 10㎛, has a relatively reduced aperture ratio of the mesh structure and is indistinctly visible to the user in a specific direction.

[0143] In addition, Example 11, in which a transparent conductive oxide layer was not formed, had reduced corrosion resistance compared to the remaining examples in which a transparent conductive oxide layer was formed.

[0144] In the case of Comparative Example 6, which did not form a metal oxide layer and a transparent conductive oxide layer, the copper layer, which is prone to oxidation, was directly exposed, and the corrosion resistance of the antenna unit was significantly reduced.

[0145] FIG. 8 is the result of evaluating the color and pattern visibility of antenna elements according to the examples and comparative examples, and FIG. 9 is a graph showing the a* and b* values ​​of the CIE L*a*b* color system and the corresponding colors of antenna elements according to the examples and comparative examples.

[0146] Specifically, FIGS. 8 and 9 show the evaluation results of color, visibility, and a* value / b* value according to the thickness of the metal oxide layer of Examples 1 to 6 and Comparative Examples 1 to 5, which have different thicknesses. When evaluating the pattern visibility in FIG. 8, the visibility of the antenna unit above the lower right line segment was determined based on the lower right line segment.

[0147] Referring to FIGS. 8 and 9, Comparative Examples 1 to 3, in which the thickness of the metal oxide layer is less than 60 nm, have an a* value of the CIE L*a*b* color system exceeding 0.5, and accordingly, a reddish phenomenon occurs, and a reddish pattern is visible from the outside.

[0148] In addition, Comparative Examples 4 and 5, in which the thickness of the metal oxide layer exceeds 100 nm, have a b* value of the CIE L*a*b* color system exceeding 0.5, and accordingly, sulfidation occurs, and a yellow-toned pattern is visible from the outside.

[0149] As shown in FIGS. 8 and 9, the antenna units according to Examples 1 to 6 suppress external visibility, and both the a* value and the b* value are formed to be 0.5 or less, thereby preventing red or yellowing phenomena. Explanation of the symbols

[0151] 100: Antenna element 110: Dielectric layer 120: Antenna unit 130: Metal layer 140: Metal oxide layer 150: Transparent conductive oxide layer 122: Radiator 124: Transmission line 126: Signal pad 128: Ground pad 161: First pressure-sensitive adhesive layer 163: Second pressure-sensitive adhesive layer 200: Flexible printed circuit board 210: Core layer 220: Signal wiring 250: Intermediate circuit board 260: Antenna driver IC chip 300: Image display device 305: Display panel 310: Optical layer 320: Cover Window

Claims

Claim 1 An antenna element comprising: a dielectric layer; and an antenna unit including a metal layer, a metal oxide layer, and a transparent conductive oxide layer sequentially stacked on the dielectric layer, wherein the metal oxide layer is an oxide of copper or an alloy containing copper, and the transparent conductive oxide layer comprises at least one of indium tin oxide (ITO), indium zinc oxide (IZO), indium zinc tin oxide (ITZO), and zinc oxide (ZnOx), wherein the thickness of the metal layer is 200 to 1,000 nm, the metal oxide layer is provided as a blackening treatment portion, and the thickness of the metal oxide layer is 60 to 100 nm. Claim 2 delete Claim 3 An antenna element according to claim 1, wherein the a* value and the b* value in the International Commission on Illumination (CIE) L*a*b* color system are each -1.0 to 0.

5. Claim 4 An antenna element according to claim 3, wherein the a* value and the b* value are each -0.6 to 0.

3. Claim 5 delete Claim 6 An antenna element according to claim 1, wherein the transparent conductive oxide layer is further disposed between the dielectric layer and the metal layer. Claim 7 delete Claim 8 delete Claim 9 An antenna element according to claim 1, wherein the antenna unit comprises a radiator, a transmission line extending from the radiator, a signal pad connected to the end of the transmission line, and a pair of ground pads spaced apart from the transmission line and the signal pad and positioned with the signal pad in between. Claim 10 An antenna element according to claim 9, wherein the radiator and the transmission line comprise a mesh structure. Claim 11 An antenna element according to claim 10, wherein the mesh structure comprises a plurality of intersecting conductive lines, and the line width of each of the conductive lines is 0.5 to 10 μm. Claim 12 An antenna element according to claim 9, wherein the signal pad and the ground pad include a solid pattern. Claim 13 An antenna element according to claim 9, wherein the metal oxide layer is included only in the radiator and the transmission line. Claim 14 An antenna element according to claim 9, wherein the metal oxide layer is included in all of the radiator, the transmission line, the signal pad, and the ground pad. Claim 15 An image display device comprising a display panel; and an antenna element of claim 1 disposed on the display panel. Claim 16 An image display device according to claim 15, further comprising an optical layer disposed on the display panel and a cover window disposed on the antenna element, wherein the antenna element is disposed between the optical layer and the cover window.

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