Patent Publication Number: US-2022229472-A1

Title: Antenna package and image display device including the same

Description:
CROSS-REFERENCE TO RELATED APPLICATION AND CLAIM OF PRIORITY 
     This application claims priority to Korean Patent Application No. 10-2021-0006774 filed on Jan. 18, 2021 in the Korean Intellectual Property Office (KIPO), the entire disclosures of which are incorporated by reference herein. 
     BACKGROUND 
     1. Field 
     The present invention relates to an antenna package and an image display device including the same. More particularly, the present invention relates to an antenna package including an antenna device and a circuit board, and an image display device including the same. 
     2. Description of the Related Art 
     As information technologies have been developed, a wireless communication technology such as Wi-Fi, Bluetooth, etc., is combined with an image display device in, e.g., a smartphone form. In this case, an antenna may be combined with the image display device to provide a communication function. 
     According to developments of a mobile communication technology, an antenna capable of implementing, e.g., high frequency or ultra-high frequency band communication is needed in the display device. 
     However, if a driving frequency of the antenna increases, a signal loss may be increased. Further, as a length of a transmission path increases, an antenna gain may be decreased. 
     To connect the antenna to, e.g., a main board of the image display device, a connection intermediate structure such as a printed circuit board may be added. In this case, the signal loss may also be increased by the connection intermediate structure. 
     Additionally, when the antenna is disposed on a front side of the image display device, a radiation direction of the antenna is limited. Thus, a broadband or high coverage antenna radiation may be substantially limited. When the antenna is inserted into an image display device to improve antenna radiation properties, a thickness of the image display device may increase and a radiation interference may occur due to a conductive structure of a display panel. 
     For example, Korean Published Patent Application No. 2013-0095451 discloses an antenna integrated into a display panel, but does not provide any efficient circuit connection in consideration of the above-described issues. 
     SUMMARY 
     According to an aspect of the present invention, there is provided an antenna package having improved radiational property and spatial efficiency. 
     According to an aspect of the present invention, there is provided an image display device including an antenna package with improved radiational property and spatial efficiency. 
     (1) An antenna package, including: an antenna device including an antenna unit that includes a first radiator; and an intermediate circuit board coupled to the antenna device to be electrically connected to the antenna unit, the intermediate circuit board including: a core layer; a first feeding wiring formed on one surface of the core layer and electrically connected to the antenna unit; and a second radiator formed on the one surface of the core layer. 
     (2) The antenna package of the above (1), wherein the intermediate circuit board further includes a second feeding wiring extending from the second radiator on the one surface of the core layer. 
     (3) The antenna package of the above (2), wherein the intermediate circuit board further includes a third radiator formed on the one surface of the core layer. 
     (4) The antenna package of the above (3), wherein the intermediate circuit board further includes a third feeding wiring extending from the third radiator on the one surface of the core layer. 
     (5) The antenna package of the above (4), wherein the core layer has a first region bonded to the antenna device, a second region having a bending region and a third region having an end portion of the intermediate circuit board, and the second radiator is formed on the second region of the core layer, and the third radiator is formed on the third region of the core layer. 
     (6) The antenna package of the above (5), wherein the second radiator serves as a horizontal radiator with respect to the antenna device, and the third radiator serves as a vertical radiator in a bottom surface direction of the antenna device. 
     (7) The antenna package of the above (6), wherein the first radiator is a vertical radiator in a top surface direction of the antenna device. 
     (8) The antenna package of the above (5), wherein the second feeding wiring extends from the second radiator on the second region and the third region, and the third feeding wiring extends from the third radiator on the third region. 
     (9) The antenna package of the above (5), wherein the first radiator has a different size or a different resonance frequency from that of the second radiator or the third radiator. 
     (10) The antenna package of the above (9), wherein the first radiator, the second radiator and the third radiator have sizes that sequentially decrease. 
     (11) The antenna package of the above (9), wherein the first radiator, the second radiator and the third radiator have resonance frequencies that sequentially increase. 
     (12) The antenna package of the above (5), further including an antenna driving integrated circuit chip electrically connected to the first feeding wiring, the second feeding wiring and the third feed wiring by the third region of the core layer. 
     (13) The antenna package of the above (5), wherein the first feeding wiring, the second feeding wiring, the third feeding wiring, the second radiator and the third radiator are formed together at the same layer on the one surface of the core layer. 
     (14) The antenna package of the above (5), wherein the second radiator has a curved shape. 
     (15) An image display device, including: a display panel; and the antenna package according to embodiments as described above disposed on the display panel. 
     (16) The image display device of the above (15), further including a chip mounting board disposed under the display panel, and an antenna driving integrated circuit chip mounted on the chip mounting board, wherein the intermediate circuit board of the antenna package is bent under the display panel to be coupled to the chip mounting board and electrically connected to the antenna driving integrated circuit chip. 
     (17) The image display device of the above (16), wherein the second radiator is disposed on a lateral portion of the display panel. 
     (18) The image display device of the above (17), wherein the intermediate circuit board further includes a third radiator formed on the one surface of the core layer and disposed under the display panel. 
     According to embodiments of the present invention, an antenna unit included in an antenna device may be substantially used as an antenna-on-display (AOD) antenna, and an additional antenna unit may be formed on a circuit board connected to the antenna unit. A total antenna gain may be improved through the antenna unit included in the circuit board, and antenna radiation direction or radiation coverage may be extended by a bending of the circuit board. 
     Accordingly, an antenna package capable of increasing radiation coverage and radiation band while maintaining or improving radiation property and reliability may be provided. 
     In some embodiments, the antenna unit included in the circuit board may be used as a high-frequency antenna having a higher resonance frequency than that of the AOD antenna to substantially implement a multi-band antenna. 
    
    
     
       BRIEF DESCRIPTION OF THE DRAWINGS 
         FIG. 1  is a schematic top planar view illustrating an antenna package in accordance with exemplary embodiments. 
         FIG. 2  is a schematic cross-sectional view illustrating an antenna package in accordance with exemplary embodiments. 
         FIG. 3  is a schematic top planar view illustrating an antenna package in accordance with some exemplary embodiments. 
         FIGS. 4 and 5  are a schematic cross-sectional view and a schematic top planar view, respectively, illustrating an image display device in accordance with exemplary embodiments. 
     
    
    
     DETAILED DESCRIPTION OF THE EMBODIMENTS 
     According to exemplary embodiments of the present invention, there is provided an antenna package where an antenna device and a circuit board are combined, and a plurality of antenna units are included. According to exemplary embodiments of the present invention, there is also provided an image display device including the antenna package 
     Hereinafter, the present invention will be described in detail with reference to the accompanying drawings. However, those skilled in the art will appreciate that such embodiments described with reference to the accompanying drawings are provided to further understand the spirit of the present invention and do not limit subject matters to be protected as disclosed in the detailed description and appended claims. 
       FIG. 1  is a schematic top planar view illustrating an antenna package in accordance with exemplary embodiments.  FIG. 2  is a schematic cross-sectional view illustrating an antenna package in accordance with exemplary embodiments. For example, for convenience of descriptions, an intermediate circuit board is shown in a flat state before being bent in  FIGS. 1 and 2 . 
     Referring to  FIGS. 1 and 2 , the antenna package may include an antenna device  100  and an intermediate circuit board  200 . 
     The antenna device  100  may include an antenna dielectric layer  110  and an antenna unit layer  120  disposed on the antenna dielectric layer  110 . 
     The antenna dielectric layer  110  may include a transparent resin film that may include a polyester-based resin such as polyethylene terephthalate, polyethylene isophthalate, polyethylene naphthalate and polybutylene terephthalate; a cellulose-based resin such as diacetyl cellulose and triacetyl cellulose; a polycarbonate-based resin; an acrylic resin such as polymethyl (meth)acrylate and polyethyl (meth)acrylate; a styrene-based resin such as polystyrene and an acrylonitrile-styrene copolymer; a polyolefin-based resin such as polyethylene, polypropylene, a cycloolefin or polyolefin having a norbornene structure and an ethylene-propylene copolymer; a vinyl chloride-based resin; an amide-based resin such as nylon and an aromatic polyamide; an imide-based resin; a polyethersulfone-based resin; a sulfone-based resin; a polyether ether ketone-based resin; a polyphenylene sulfide resin; a vinyl alcohol-based resin; a vinylidene chloride-based resin; a vinyl butyral-based resin; an allylate-based resin; a polyoxymethylene-based resin; an epoxy-based resin; a urethane or acrylic urethane-based resin; a silicone-based resin, etc. These may be used alone or in a combination of two or more therefrom. 
     In an embodiment, the antenna dielectric layer  110  may include a cycloolefin polymer (COP) layer for a stable formation of an antenna unit to be described later and a connection reliability with the intermediate circuit board  200 . 
     The antenna 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 antenna dielectric layer  110  may include an inorganic insulating material such as silicon oxide, silicon nitride, silicon oxynitride, glass, or the like. 
     In some embodiments, a dielectric constant of the antenna dielectric layer  110  may be adjusted in a range from about 1.5 to about 12. When the dielectric constant exceeds about 12, a driving frequency may be excessively decreased, so that driving in a desired high or ultra-high frequency band may not be implemented. 
     The antenna unit layer  120  may include an antenna unit formed on a top surface of the antenna dielectric layer  110 . For example, a plurality of the antenna units may be arranged along a width direction of the antenna device  100 . 
     The antenna unit may include a first radiator  122  and a transmission line  124 . The first radiator  122  may have, e.g., a polygonal plate shape, and the transmission line  124  may extend from one side of the first radiator  122 . The transmission line  124  may be formed as a single member substantially integral with the first radiator  122 , and may have a narrower width than that of the first radiator  122 . 
     The antenna unit may further include a signal pad  126 . The signal pad  126  may be connected to a terminal end portion of the transmission line  124 . In an embodiment, the signal pad  126  may be provided as a member substantially integral with the transmission line  124 , and the terminal end portion of the transmission line  124  may serve as the signal pad  126 . 
     In some embodiments, a ground pad  128  may be disposed around the signal pad  126 . For example, a pair of the ground pads  128  may be disposed to face each other with the signal pad  126  interposed therebetween. The ground pad  128  may be electrically and physically separated from the transmission line  124  and the signal pad  126 . 
     The antenna unit or the first radiator  122  may be designed to have, e.g., a resonance frequency corresponding to a high frequency or an ultra-high frequency band such as 3G, 4G, 5G or higher bands. For example, the resonance frequency of the antenna unit may have a resonance frequency of about 10 GHz or more, or in a range from about 20 to 40 GHz. 
     The antenna unit 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 the metals. These may be used alone or in combination of at least two therefrom. 
     The antenna unit may include silver (Ag) or a silver alloy (e.g., silver-palladium-copper (APC)), or copper (Cu) or a copper alloy (e.g., a copper-calcium (CuCa)) to implement a low resistance and a fine line width pattern. 
     In some embodiments, the antenna unit may include a transparent conductive oxide such as indium tin oxide (ITO), indium zinc oxide (IZO), zinc oxide (ZnOx), indium zinc tin oxide (IZTO), etc. 
     In some embodiments, the antenna unit may include a stacked structure of a transparent conductive oxide layer and a metal layer. For example, the antenna unit may include a double-layered structure of a transparent conductive oxide layer-metal layer, or a triple-layered structure of a transparent conductive oxide layer-metal layer-transparent conductive oxide layer. In this case, flexible property may be improved by the metal layer, and a signal transmission speed may also be improved by a low resistance of the metal layer. Corrosive resistance and transparency may be improved by the transparent conductive oxide layer. 
     In some embodiments, the antenna unit may include a blackened portion, so that a reflectance at a surface of the antenna unit may be decreased to suppress a visual recognition of the antenna unit due to a light reflectance. 
     In an embodiment, a surface of the metal layer included in the antenna unit may be converted into a metal oxide or a metal sulfide to form a blackened layer. In an embodiment, a blackened layer such as a black material coating layer or a plating layer may be formed on the antenna unit 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 or alloy containing at least one therefrom. 
     A composition and a thickness of the blackened layer may be adjusted in consideration of a reflectance reduction effect and an antenna radiation property. 
     In some embodiments, as illustrated in  FIG. 1 , the first radiator  122  and the transmission line  124  may include a mesh-pattern structure to improve transmittance. In this case, a dummy mesh pattern (not illustrated) may be formed around the first radiator  122  and the transmission line  124 . 
     The signal pad  126  and the ground pad  128  may have a solid pattern structure formed of the above-described metal or alloy in consideration of reduction of a feeding resistance, noise absorption efficiency, improvement of horizontal radiation property, etc. 
     In an embodiment, the radiator  122  may have the mesh-pattern structure, and at least a portion of the transmission line  124  may include a solid metal pattern. 
     The first radiator  122  may be disposed in a display area of the image display device, and the signal pad  126  and the ground pad  128  may be disposed in a non-display area or a bezel area of the image display device. At least a portion of the transmission line  124  may also be disposed in the non-display area or the bezel area. 
     An antenna ground layer  130  may be formed on a bottom surface of the antenna dielectric layer  110 . The antenna ground layer  130  may include the aforementioned metal and/or alloy. 
     In some embodiments, the antenna ground layer  130  may be included as an independent component of the antenna device  100 . In some embodiments, a conductive member of the image display device on which the antenna device  100  is applied may serve as the antenna ground layer  130 . 
     The conductive member may include, e.g., a gate electrode of a thin film transistor (TFT), various wirings such as a scan line or a data line, various electrodes such as a pixel electrode or a common electrode included in a display panel. 
     In an embodiment, various structures including a conductive material disposed under, e.g., the display panel may serve as the antenna ground layer  130 . 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 serve as the antenna ground layer  130 . 
     The intermediate circuit board  200  may include a core layer  210  and a conductive layer  220  formed on one surface of the core layer  210 . A ground layer  230  may be formed on the other surface of the core layer  210  opposite to the one surface. 
     The intermediate circuit board  200  may be fabricated from, e.g., a flexible printed circuit board (FPCB). 
     The core layer  210  may include a flexible resin. For example, the core layer  210  may include a flexible resin such as a polyimide resin, a modified polyimide (MPI), an epoxy resin, polyester, a cycloolefin polymer (COP), a liquid crystal polymer (LCP), or the like. The core layer  210  may include an internal insulating layer included in the intermediate circuit board  200 . 
     Preferably, the core layer  210  may include the LCP or the MPI to provide sufficient flexible and bending properties. 
     The conductive layer  220  may include a first feeding wiring  222  electrically connected to the antenna unit layer  120 . The first feeding wiring  222  may be connected to or bonded to the signal pad  126  of the antenna unit layer  120 . 
     For example, one end portion of the first feeding wiring  222  may be exposed by partially removing a coverlay film (not illustrated) of the circuit board  200 . The exposed one end portion of the first feeding wiring  222  may be bonded to the antenna unit layer  120  including the signal pad  126 . 
     For example, the intermediate circuit board  200  and the antenna device  100  may be bonded to each other through a heat treatment/pressurization process utilizing a conductive bonding structure  150  such as an anisotropic conductive film (ACF). 
     The intermediate circuit board  200  or the core layer  210  may include a first region I, a second region II and a third region III. The first region I may be provided as a bonding region between the intermediate circuit board  200  and the antenna device  100 . 
     In exemplary embodiments, the second region II may be located between the first region I and the third region III, and may serve as a bending region of the intermediate circuit board  200 . For example, the intermediate circuit board  200  may be bent or folded by the second region II so that the third region III may be disposed under the display panel. 
     In this case, the second region II may be located on a lateral portion of the display panel. 
     In exemplary embodiments, the conductive layer  220  of the intermediate circuit board  200  may include a second radiator  224 . The second radiator  224  may be formed on the one surface of the core layer  210  of the second region II. In some embodiments, the second radiator  224  may be formed at the same layer or at the same level as that of the first feeding wiring  222 . 
     For example, a plurality of the second radiators  224  may be arranged along a width direction of the intermediate circuit board  200  in the second region II. 
     A second feeding wiring  226  may extend from one side of the second radiator  224 . The second feeding wiring  226  may extend from one side of the second radiator  224 , and may extend throughout the second region II and the third region III. 
     In some embodiments, the conductive layer  220  of the intermediate circuit board  200  may further include a third radiator  223 . The third radiator  223  may be formed on the one surface of the core layer  210  of the third region III. In some embodiments, the third radiator  223  may be formed at the same layer or at the same level as that of the first feeding wiring  222 . 
     For example, a plurality of the third radiators  223  may be arranged along the width direction of the intermediate circuit board  200  in the third region III. 
     A third feeding wiring  225  may extend from one side of the third radiator  223 . The third feeding wiring  225  may extend from the one side of the third radiator  223  on the third region III. 
     According to the above-described exemplary embodiments, the first radiator  122  may be substantially serve as an AOD (Antenna-On Display) antenna unit. Accordingly, sufficient radiation properties and gain may be achieved from a front portion of an image display device through the first radiator  122 . For example, a vertical radiation in a direction to the front portion of the image display device may be implemented through the first radiator  122 . 
     The second radiator  224  and the third radiator  223  may serve as an antenna unit substantially integrated with the intermediate circuit board  200 . Accordingly, while feeding and signal control of the AOD antenna unit are performed by the intermediate circuit board  200 , an auxiliary antenna radiation may be implemented. The core layer  210  of the intermediate circuit board  200  may be substantially serve as an antenna dielectric layer for the second radiator  224  and the third radiator  223 . 
     For example, a horizontal radiation in a lateral direction of the image display device may be implemented through the second radiator  224 , and a vertical radiation in a rear direction of the image display device may be implemented through the third radiator  223 . 
     Accordingly, an antenna radiation coverage provided from the image display device may be extended utilizing the intermediate circuit board  200 . Additionally, the horizontal radiation and the rear vertical radiation through the second radiator  224  and the third radiator  223  may be easily implemented by bending of the intermediate circuit board  200  having relatively improved flexibility. 
     In some embodiments, the second radiator  224  and the third radiator  223  may be disposed at a peripheral portion (or a bezel portion) and a rear portion of the image display device, respectively, as the intermediate circuit board  200  is bent. Thus, the second radiator  224  and the third radiator  223  may not be visually recognized by a user, and thus may be formed of a solid metal pattern, thereby improving a signal efficiency by a low resistance. 
     As described above, the first radiator  122  may be provided as an AOD antenna pattern. Accordingly, the first radiator  122  may be formed in a mesh-pattern structure to increase transmittance and prevent a visual recognition by the user. 
     The ground layer  230  may be formed on the bottom surface of the core layer  210  throughout the first region I, the second region II and the third region III. The ground layer  230  may cover the first to third feeding wirings  222 ,  226  and  225  in a planar view to promote feeding and signaling to the first to third radiators  122 ,  224  and  223  by a formation of an electric field. 
     The ground layer  230  may also overlap the second radiator  224  and the third radiator  223  in a thickness direction or in the planar view to induce the antenna radiation from the intermediate circuit board  200 . 
     The conductive layer  220  and the ground layer  230  of the intermediate circuit board  200  may include the above-described metal or alloy. For example, the conductive layer  210  and the ground layer  230  may be fabricated from a metal layer included on one surface and the other surface of a copper clad laminate. For example, the first to third feeding wirings  222 ,  226  and  225 , the second radiator  224  and the third radiator  223  may be formed by etching the metal layer formed on the one surface of the copper clad laminate. 
     As illustrated in  FIG. 2 , the intermediate circuit board  200  may be electrically connected to a chip mounting board  300 . 
     For example, terminal end portions of the first to third feeding wirings  222 ,  226  and  225  may be electrically connected to the connection wirings  330  included in the chip mounting board  300  through a connector  320 . 
     An antenna driving integrated circuit (IC) chip  340  may be mounted on the chip mounting board  300  using a surface mounting technology (SMT) to be electrically connected to the connection wirings  330 . Accordingly, feeding and applying a control signal (e.g., a phase signal, a beam tilting signal, etc.) may be performed to the first to third radiators  122 ,  224  and  223  through the antenna driving IC chip  340 . 
     The chip mounting board  300  may include, e.g., a main board, a package board, or a rigid printed circuit board. The chip mounting board  300  may include an insulating body  310  on which the connector  320 , the connection wiring  330  and the antenna driving integrated circuit (IC) chip  340  are disposed. The insulating body  310  may include, e.g., a resin impregnated with an inorganic material such as glass fiber (e.g., a prepreg), and may have higher rigidity or lower flexibility than that of the core layer  210 . 
       FIG. 3  is a schematic top planar view illustrating an antenna package in accordance with some exemplary embodiments. Detailed descriptions of elements and structures substantially the same as or similar to those described with reference to  FIGS. 1 and 2  are be omitted herein. 
     Referring to  FIG. 3 , the antenna package may include radiators having different sizes and/or resonance frequencies. For example, the first to third radiators  122 ,  224  and  223  may have different sizes. 
     In an embodiment, the first radiator  122  having a relatively long signal path through the first feeding wiring  222  may have a relatively low resonance frequency and a large size to prevent degradation of radiation reliability due to a signal loss. 
     In an embodiment, the third radiator  223  having a short signal path through the third feeding wiring  225  may have a relatively high frequency and a small size. 
     For example, the first radiator  122 , the second radiator  224  and the third radiator  223  may have sequentially decreasing sizes. For example, in a range from 10 GHz to 40 GHz, the first radiator  122 , the second radiator  224  and the third radiator  223  may have resonant frequencies that may sequentially increase. 
       FIGS. 4 and 5  are a schematic cross-sectional view and a schematic top planar view, respectively, illustrating an image display device in accordance with exemplary embodiments. For convenience of descriptions, illustrations of some elements of the antenna device  100  and the intermediate circuit board  200  are omitted. For example, an illustration of the feeding wiring in the conductive layer  220  of the intermediate circuit board  200  is omitted. In  FIG. 5 , the second region II of the intermediate circuit board  200  is shown in a flat state before being bent. 
     Referring to  FIGS. 4 and 5 , an image display device  400  may be fabricated in the form of, e.g., a smart phone, and  FIG. 5  illustrates a front portion or a window surface of the image display device  400 . The front portion of the image display device  400  may include a display area  410  and a peripheral area  420 . The peripheral area  420  may correspond to, e.g., a light-shielding portion or a bezel portion of the image display device. 
     The antenna device  100  included in the above-described antenna package may be disposed toward the front portion of the image display device  400 , and may be disposed on, e.g., the display panel  405 . In an embodiment, the first radiator  122  may be at least partially disposed in the display area  410 . 
     In this case, the first radiator  122  may include a mesh-pattern structure, and a reduction of transmittance due to the first radiator  122  may be prevented. The pads  126  and  128  included in the antenna unit may be formed of a solid metal pattern, and may be disposed in the peripheral area  420  to prevent degradation of an image quality. 
     In some embodiments, the intermediate circuit board  200  may be bent and disposed on a rear portion of the image display device  400  to extend toward the chip mounting board  300  on which the antenna driving IC chip  340  is mounted. 
     As described above, the first region I of the intermediate circuit board  200  may be bonded to the antenna device  100 , and the second region II may be bent to be disposed on, e.g., a lateral portion of the display panel  405 . The second radiator  224  may be disposed on the lateral portion of the display panel  405  to provide the horizontal radiation. For example, the second radiator  224  may have a curved shape. 
     The third region III of the intermediate circuit board  200  may be located under the display panel  405  or at the rear portion of the image display device. For example, the third region III may face the antenna device  100 . 
     Accordingly, the third radiator  223  may be provided as a vertical radiator at the rear portion. Therefore, radiation may be provided together in the front, rear and lateral directions of the image display device so that an antenna coverage may be expanded.