PATENT DOCUMENT

Publication Number: US-10734708-B2
Application Number: US-201816032948-A
Country: US
Kind Code: B2

Title: Antennas formed from conductive display layers

Abstract:
An electronic device such as a wristwatch may be provided with wireless circuitry and a display having a display module and a cover layer. The display module may include a dielectric layer. Touch sensor electrodes may be formed from conductive traces on the dielectric layer. An antenna may be embedded within the display module. The antenna may include an antenna resonating element formed from a grid of intersecting conductive traces on the dielectric layer. The grid may have edges that define a lateral outline of the antenna resonating element. The outline may have a length that configures the antenna to radiate at a desired frequency. The antenna resonating element may be formed from indium tin oxide and may be substantially transparent.

Claims:
What is claimed is: 
     
       1. An electronic device comprising:
 a display having a cover layer and a display module, wherein the display module is configured to display images through the cover layer and comprises a plurality of stacked dielectric layers coupled to the cover layer; 
 a conductive layer on a surface of a dielectric layer in the plurality of stacked dielectric layers; and 
 an antenna having an antenna resonating element formed from a grid of intersecting conductive traces in the conductive layer, wherein the antenna is configured to transmit radio-frequency signals through the cover layer, the antenna comprises an antenna ground separated from the conductive layer by at least the dielectric layer, an additional conductive layer is formed on an additional dielectric layer in the plurality of stacked dielectric layers, and the antenna ground comprises an additional grid of intersecting conductive traces in the additional conductive layer. 
 
     
     
       2. The electronic device defined in  claim 1 , wherein the antenna comprises a positive antenna feed terminal coupled to the grid of intersecting conductive traces. 
     
     
       3. The electronic device defined in  claim 2 , wherein the grid of intersecting conductive traces comprises a plurality of slots, each slot in the plurality of slots is surrounded by at least some of the intersecting conductive traces in the grid of intersecting conductive traces, and the grid of intersecting conductive traces has edges that define an outline of the antenna resonating element and that surround each of the slots in the plurality of slots. 
     
     
       4. The electronic device defined in  claim 3 , wherein at least one of the edges has a length approximately equal to one-half of a wavelength of operation for the antenna. 
     
     
       5. The electronic device defined in  claim 2 , further comprising:
 radio-frequency transceiver circuitry; and 
 a conductive via coupled to the positive antenna feed terminal through the dielectric layer, wherein the conductive via is configured to convey the radio-frequency signals from the radio-frequency transceiver circuitry to the positive antenna feed terminal. 
 
     
     
       6. The electronic device defined in  claim 2 , further comprising:
 radio-frequency transceiver circuitry; 
 touch sensor electrodes on the display module; and 
 a flexible printed circuit coupled to the display module, wherein the flexible printed circuit comprises:
 a first conductive trace coupled to the touch sensor electrodes, and 
 a radio-frequency transmission line coupled between the radio-frequency transceiver circuitry and the positive antenna feed terminal. 
 
 
     
     
       7. An electronic device comprising:
 a display having a cover layer and a display module, wherein the display module is configured to display images through the cover layer and comprises a plurality of stacked dielectric layers coupled to the cover layer; 
 a conductive layer on a surface of a dielectric layer in the plurality of stacked dielectric layers; 
 an antenna having an antenna resonating element formed from a grid of intersecting conductive traces in the conductive layer, wherein the antenna is configured to transmit radio-frequency signals through the cover layer and the antenna comprises an antenna ground separated from the conductive layer by at least the dielectric layer; 
 radio-frequency transceiver circuitry, wherein the plurality of stacked dielectric layers comprises first and second additional dielectric layers, the first additional dielectric layer is interposed between the dielectric layer and the second additional dielectric layer, and the antenna ground comprises a first conductive trace on the second additional dielectric layer; 
 a second conductive trace on the first additional dielectric layer; and 
 a conductive via coupled to the second conductive trace through the first and second additional dielectric layers, wherein the conductive via is configured to convey the radio-frequency signals from the radio-frequency transceiver circuitry to the second conductive trace and the second conductive trace is configured to indirectly feed the radio-frequency signals to the grid of intersecting conductive traces via near-field electromagnetic coupling. 
 
     
     
       8. An electronic device comprising:
 a display having a cover layer and a display module, wherein the display module is configured to display images through the cover layer and comprises a plurality of stacked dielectric layers coupled to the cover layer; 
 a conductive layer on a surface of a dielectric layer in the plurality of stacked dielectric layers; and 
 an antenna having an antenna resonating element formed from a grid of intersecting conductive traces in the conductive layer, wherein the antenna is configured to transmit radio-frequency signals through the cover layer, 
 the grid of conductive traces comprises an array of rectangular openings in the conductive layer, and each of the rectangular openings has edges defined by four respective segments of the intersecting conductive traces from the grid of intersecting conductive traces. 
 
     
     
       9. The electronic device defined in  claim 8 , wherein each of the rectangular openings has a length between 0.1 mm and 5 mm. 
     
     
       10. The electronic device defined in  claim 9 , wherein each of the segments has a width between 0.01 mm and 0.20 mm. 
     
     
       11. The electronic device defined in  claim 1 , wherein the conductive layer comprises an indium tin oxide (ITO) layer and the grid of intersecting conductive traces comprises a grid of intersecting ITO traces. 
     
     
       12. The electronic device defined in  claim 11 , wherein the display comprises touch sensor electrodes formed from the ITO layer and the touch sensor electrodes are separated from the grid of intersecting ITO traces by a gap. 
     
     
       13. The electronic device defined in  claim 1 , wherein the grid of intersecting conductive traces directly contacts the display cover layer. 
     
     
       14. An electronic device comprising:
 a first dielectric layer; 
 a second dielectric layer on the first dielectric layer; 
 a patch antenna having a patch antenna resonating element, wherein the patch antenna resonating element comprises a grid of conductive traces on the second dielectric layer, the grid of conductive traces defining edges of an array of slots within the patch antenna resonating element; 
 a ground layer on the first dielectric layer; 
 a positive antenna feed terminal coupled to the grid of conductive traces; and 
 a ground antenna feed terminal coupled to the ground layer, wherein the ground layer comprises an additional grid of conductive traces on the first dielectric layer, the additional grid of conductive traces defining edges of an additional array of slots within the ground layer. 
 
     
     
       15. The electronic device defined in  claim 14 , wherein each slot in the array of slots and each slot in the additional array of slots has a length that is between 0.1 mm and 5.0 mm. 
     
     
       16. The electronic device defined in  claim 14 , further comprising:
 a dielectric cover layer that forms part of an exterior surface of the electronic device, wherein the first and second dielectric layers are mounted to the dielectric cover layer and the patch antenna is configured to radiate through the dielectric cover layer. 
 
     
     
       17. The electronic device defined in  claim 16 , further comprising touch sensor electrodes on the first dielectric layer and configured to receive a touch input through the dielectric cover layer. 
     
     
       18. The electronic device defined in  claim 17 , wherein the grid of conductive traces and the touch sensor electrodes comprise indium tin oxide (ITO).

Description:
BACKGROUND 
     This relates generally to electronic devices and, more particularly, to electronic devices with wireless communications circuitry. 
     Electronic devices often include wireless circuitry with antennas. For example, cellular telephones, computers, and other devices often contain antennas for supporting wireless communications. 
     It can be challenging to form electronic device antenna structures with desired attributes. In some wireless devices, the presence of conductive structures such as conductive housing structures can influence antenna performance. Antenna performance may not be satisfactory if the housing structures are not configured properly and interfere with antenna operation. Device size can also affect performance. It can be difficult to achieve desired performance levels in a compact device, particularly when the compact device has conductive housing structures. 
     It would therefore be desirable to be able to provide improved wireless communications circuitry for wireless electronic devices. 
     SUMMARY 
     An electronic device such as a wristwatch may be provided with wireless circuitry. The electronic device may have a display with a display module and a display cover layer overlapping the display module. The display module may include stacked dielectric layers. Display circuitry such as pixel circuitry and touch sensor electrodes may be formed on the stacked dielectric layers. 
     The wireless circuitry may include an antenna embedded within the display module. The antenna may have an antenna resonating element such as a patch antenna resonating element. The antenna resonating element may be formed from a conductive layer on one of the dielectric layers. The conductive layer may include a grid of intersecting conductive traces that form the antenna resonating element. The grid may have edges that define a lateral outline of the antenna resonating element. The outline may have a length that configures the antenna to radiate at a desired frequency. The grid may include segments of conductive traces that surround an array of slots within the antenna resonating element. The slots may each have a length between 0.1 mm and 5.0 mm. The segments may each have a width between 0.01 mm and 0.20 mm. The antenna may include a ground plane formed on an additional dielectric layer below the antenna resonating element. The ground plane may include a grid of intersecting conductive traces. 
     The antenna resonating element may be fed using a conductive via extending through the dielectric layer. In another suitable arrangement, the antenna is fed using a transmission line on a flexible printed circuit coupled to the display module. The flexible printed circuit may carry conductive traces coupled to the touch sensor electrodes in the display module. In yet another suitable arrangement, the antenna may be fed using an indirect feed element embedded in the display module. The antenna may radiate through the display cover layer. 
     Touch sensor electrodes may be formed on the same dielectric layer as the antenna resonating element. The grid of conductive traces and the touch sensor electrodes may be formed from indium tin oxide (ITO). The antenna resonating element may be substantially transparent or invisible to view by a user of the device. The antenna may be embedded in other dielectric substrates mounted to other dielectric cover layers in the device if desired. 
    
    
     
       BRIEF DESCRIPTION OF THE DRAWINGS 
         FIG. 1  is a perspective view of an illustrative electronic device with wireless circuitry in accordance with an embodiment. 
         FIG. 2  is a schematic diagram of an illustrative electronic device with wireless circuitry in accordance with an embodiment. 
         FIG. 3  is a diagram of an illustrative transceiver circuit and antenna in accordance with an embodiment. 
         FIG. 4  is a diagram of an antenna formed from a grid of conductive traces in a conductive layer in accordance with an embodiment. 
         FIG. 5  is a perspective view of a grid of conductive traces in a conductive layer that can be used to form antenna structures in accordance with an embodiment. 
         FIG. 6  is a perspective view of an illustrative patch antenna that may be used in an electronic device in accordance with an embodiment. 
         FIG. 7  is a perspective view of an illustrative patch antenna formed from a grid of conductive traces in a conductive layer in accordance with an embodiment. 
         FIG. 8  is a cross-sectional side view of an illustrative display module showing different locations on the display module that may be used for mounting antennas of the type shown in  FIG. 7  in accordance with an embodiment. 
         FIG. 9  is a cross-sectional side view showing how an antenna mounted to a display module may be fed using a conductive via in accordance with an embodiment. 
         FIG. 10  is a cross-sectional side view showing how an antenna mounted to a display module may be fed using conductive traces on a flexible printed circuit that is also used to convey touch signals for touch sensor electrodes in the display module in accordance with an embodiment. 
         FIG. 11  is a cross-sectional side view showing how an antenna mounted to a display module may be indirectly fed in accordance with an embodiment. 
         FIG. 12  is a graph of antenna performance (antenna efficiency) for illustrative antennas of the types shown in  FIGS. 4-11  in accordance with an embodiment. 
     
    
    
     DETAILED DESCRIPTION 
     An electronic device such as electronic device  10  of  FIG. 1  may be provided with wireless circuitry. The wireless circuitry may be used to support wireless communications in one or more wireless communications bands. The wireless circuitry may include antennas. Antennas may be formed from or within electrical components or portions of electrical components such as displays, touch sensors, near-field communications antennas, wireless power coils, peripheral antenna resonating elements, conductive traces, and device housing structures, as examples. 
     Electronic device  10  may be a computing device such as a laptop computer, a computer monitor containing an embedded computer, a tablet computer, a cellular telephone, a media player, or other handheld or portable electronic device, a smaller device such as a wristwatch device, a pendant device, a headphone or earpiece device, a device embedded in eyeglasses or other equipment worn on a user&#39;s head, or other wearable or miniature device, a television, a computer display that does not contain an embedded computer, a gaming device, a navigation device, an embedded system such as a system in which electronic equipment with a display is mounted in a kiosk or automobile, equipment that implements the functionality of two or more of these devices, or other electronic equipment. In the illustrative configuration of  FIG. 1 , device  10  is a portable device such as a wristwatch (e.g., a smart watch). Other configurations may be used for device  10  if desired. The example of  FIG. 1  is merely illustrative. 
     In the example of  FIG. 1 , device  10  includes a display such as display  9 . Display  9  may be mounted in a housing such as housing  12 . Housing  12 , which may sometimes be referred to as an enclosure or case, may be formed of plastic, glass, ceramics, fiber composites, metal (e.g., stainless steel, aluminum, etc.), other suitable materials, or a combination of any two or more of these materials. Housing  12  may be formed using a unibody configuration in which some or all of housing  12  is machined or molded as a single structure or may be formed using multiple structures (e.g., an internal frame structure, one or more structures that form exterior housing surfaces, etc.). Housing  12  may have metal sidewalls such as sidewalls  12 W or sidewalls formed from other materials. Examples of metal materials that may be used for forming sidewalls  12 W include stainless steel, aluminum, silver, gold, metal alloys, or any other desired conductive material. Sidewalls  12 W may sometimes be referred to herein as housing sidewalls  12 W or conductive housing sidewalls  12 W. 
     Display  9  may be formed at (e.g., mounted on) the front side (face) of device  10 . Housing  12  may have a rear housing wall on the rear side (face) of device  10  such as rear housing wall  12 R that opposes the front face of device  10 . Conductive housing sidewalls  12 W may surround the periphery of device  10  (e.g., conductive housing sidewalls  12 W may extend around peripheral edges of device  10 ). Rear housing wall  12 R may be formed from conductive materials and/or dielectric materials. Examples of dielectric materials that may be used for forming rear housing wall  12 R include plastic, glass, sapphire, ceramic, wood, polymer, combinations of these materials, or any other desired dielectrics. 
     Rear housing wall  12 R and/or display  9  may extend across some or all of the length (e.g., parallel to the X-axis of  FIG. 1 ) and width (e.g., parallel to the Y-axis) of device  10 . Conductive housing sidewalls  12 W may extend across some or all of the height of device  10  (e.g., parallel to Z-axis). Conductive housing sidewalls  12 W and/or rear housing wall  12 R may form one or more exterior surfaces of device  10  (e.g., surfaces that are visible to a user of device  10 ) and/or may be implemented using internal structures that do not form exterior surfaces of device  10  (e.g., conductive or dielectric housing structures that are not visible to a user of device  10  such as conductive structures that are covered with layers such as thin cosmetic layers, protective coatings, and/or other coating layers that may include dielectric materials such as glass, ceramic, plastic, or other structures that form the exterior surfaces of device  10  and/or serve to hide housing walls  12 R and/or  12 W from view of the user). 
     Display  9  may be a touch screen display that incorporates a layer of conductive capacitive touch sensor electrodes or other touch sensor components (e.g., resistive touch sensor components, acoustic touch sensor components, force-based touch sensor components, light-based touch sensor components, etc.) or may be a display that is not touch-sensitive. Capacitive touch screen electrodes may be formed from an array of indium tin oxide pads or other transparent conductive structures. 
     Display  9  may include an array of display pixels formed from liquid crystal display (LCD) components, an array of electrophoretic display pixels, an array of plasma display pixels, an array of organic light-emitting diode (OLED) display pixels, an array of electrowetting display pixels, or display pixels based on other display technologies. 
     Display  9  may be protected using a display cover layer. The display cover layer may be formed from a transparent material such as glass, plastic, sapphire or other crystalline dielectric materials, ceramic, or other clear materials. The display cover layer may extend across substantially all of the length and width of device  10 , for example. 
     Device  10  may include buttons such as button  2 . There may be any suitable number of buttons in device  10  (e.g., a single button, more than one button, two or more buttons, five or more buttons, etc. Buttons may be located in openings in housing  12  (e.g., openings in conductive housing sidewall  12 W or rear housing wall  12 R) or in an opening in display  9  (as examples). Buttons may be rotary buttons, sliding buttons, buttons that are actuated by pressing on a movable button member, etc. Button members for buttons such as button  2  may be formed from metal, glass, plastic, or other materials. Button  2  may sometimes be referred to as a crown in scenarios where device  10  is a wristwatch device. 
     Device  10  may, if desired, be coupled to a strap such as strap  4 . Strap  4  may be used to hold device  10  against a user&#39;s wrist (as an example). Strap  4  may sometimes be referred to herein as wrist strap  4 . In the example of  FIG. 1 , wrist strap  4  is connected to opposing sides of device  10 . Conductive housing sidewalls  12 W may include attachment structures for securing wrist strap  4  to housing  12  (e.g., lugs or other attachment mechanisms that configure housing  12  to receive wrist strap  4 ). Configurations that do not include straps may also be used for device  10 . 
     One or more antennas may be mounted within device  10  at one or more locations such as locations  6  shown in  FIG. 1 . Locations  6  may include, for example, locations at the corners of housing  12 , locations at or near the center of display  9 , locations along the peripheral edges of housing  12 , locations between the peripheral edges of housing  12  and the center of display  9 , at rear housing wall  12 R, under the display cover glass or other dielectric display cover layer that is used in covering and protecting display  9  on the front of device  10 , under a dielectric window on rear housing wall  12 R, or elsewhere in device  10 . Locations  6  may include portions of display  9  that do not include touch sensor electrodes for gathering touch input from a user or may include portions of display  9  that do include touch sensor electrodes. In another suitable arrangement, location  8  may be used to mount an antenna within device  10 . Location  8  may extend across most of display  9  (e.g., the antenna may extend across substantially all of the lateral area of display  9 ). The antennas within device  10  may be integrated within display  9  (e.g., at locations such as locations  6  or  8 ) to optimize space consumption within device  10  and to maximize antenna efficiency given the small form factor of device  10  (particularly in scenarios where housing  12  is made from metal). Multiple antennas may be integrated within display  9  if desired (e.g., one antenna may be mounted at each location  6 ). 
       FIG. 2  is a schematic diagram showing illustrative components that may be used in device  10 . As shown in  FIG. 2 , device  10  may include control circuitry such as storage and processing circuitry  14 . Storage and processing circuitry  14  may include storage such as hard disk drive storage, nonvolatile memory (e.g., flash memory or other electrically-programmable-read-only memory configured to form a solid state drive), volatile memory (e.g., static or dynamic random-access-memory), etc. Processing circuitry in storage and processing circuitry  14  may be used to control the operation of device  10 . This processing circuitry may be based on one or more microprocessors, microcontrollers, digital signal processors, application specific integrated circuits, etc. 
     Storage and processing circuitry  14  may be used to run software on device  10 , such as internet browsing applications, voice-over-internet-protocol (VOIP) telephone call applications, email applications, media playback applications, operating system functions, etc. To support interactions with external equipment, storage and processing circuitry  14  may be used in implementing communications protocols. Communications protocols that may be implemented using storage and processing circuitry  14  include internet protocols, wireless local area network protocols (e.g., IEEE 802.11 protocols—sometimes referred to as Wi-Fi®), protocols for other short-range wireless communications links such as the Bluetooth® protocol, cellular telephone protocols, multiple-input and multiple-output (MIMO) protocols, antenna diversity protocols, etc. 
     Input-output circuitry  16  may include input-output devices  18 . Input-output devices  18  may be used to allow data to be supplied to device  10  and to allow data to be provided from device  10  to external devices. Input-output devices  18  may include user interface devices, data port devices, and other input-output components. For example, input-output devices  18  may include touch screens, displays without touch sensor capabilities, buttons, joysticks, scrolling wheels, touch pads, key pads, keyboards, microphones, cameras, buttons, speakers, status indicators, light sources, audio jacks and other audio port components, digital data port devices, light sensors, motion sensors (accelerometers), capacitance sensors, proximity sensors, fingerprint sensors (e.g., a fingerprint sensor integrated with a button), etc. 
     Input-output circuitry  16  may include wireless communications circuitry  34  for communicating wirelessly with external equipment. Wireless communications circuitry  34  may include radio-frequency (RF) transceiver circuitry formed from one or more integrated circuits, power amplifier circuitry, low-noise input amplifiers, passive RF components, one or more antennas, transmission lines, and other circuitry for handling RF wireless signals. Wireless signals can also be sent using light (e.g., using infrared communications). 
     Wireless communications circuitry  34  may include radio-frequency transceiver circuitry  20  for handling various radio-frequency communications bands. For example, circuitry  34  may include transceiver circuitry  22 ,  24 , and/or  26 . Transceiver circuitry  24  may handle 2.4 GHz and 5 GHz bands for Wi-Fi® (IEEE 802.11) communications and may handle the 2.4 GHz Bluetooth® communications band. Circuitry  34  may use cellular telephone transceiver circuitry  26  for handling wireless communications in frequency ranges such as a low communications band from 600 to 960 MHz, a low-midband from 1400-1520 MHz, a midband from 1710 to 2170 MHz, and a high band from 2300 to 2700 MHz or other communications bands between 600 MHz and 4000 MHz or other suitable frequencies (as examples). Circuitry  26  may handle voice data and non-voice data. Wireless communications circuitry  34  can include circuitry for other short-range and long-range wireless links if desired. For example, wireless communications circuitry  34  may include millimeter wave (e.g., 60 GHz) transceiver circuitry, circuitry for receiving television and radio signals, paging system transceivers, near field communications (NFC) circuitry, etc. Wireless communications circuitry  34  may include wireless power receiving circuitry and a wireless power receiving coil for wirelessly charging a battery on device  10  if desired. 
     Wireless communications circuitry  34  may include global positioning system (GPS) receiver equipment such as GPS receiver circuitry  22  for receiving GPS signals at 1575 MHz or for handling other satellite positioning data (e.g., GLONASS signals at 1609 MHz). Satellite navigation system signals for receiver  22  are received from a constellation of satellites orbiting the earth. In Wi-Fi® and Bluetooth® links and other short-range wireless links, wireless signals are typically used to convey data over tens or hundreds of feet. In cellular telephone links and other long-range links, wireless signals are typically used to convey data over thousands of feet or miles. 
     Wireless communications circuitry  34  may include one or more antennas  40 . Antennas  40  may be formed using any suitable antenna types. For example, antennas  40  may include antennas with resonating elements that are formed from patch antenna structures, loop antenna structures, dipole antenna structures, monopole antenna structures, inverted-F antenna structures, slot antenna structures, planar inverted-F antenna structures, helical antenna structures, hybrids of these designs, etc. Different types of antennas may be used for different bands and combinations of bands. For example, one type of antenna may be used in forming a local wireless link antenna and another type of antenna may be used in forming a remote wireless link antenna. If desired, two or more antennas  40  may be arranged in a phased antenna array that are operated using beam steering techniques (e.g., schemes in which antenna signal phase and/or magnitude for each antenna in an array is adjusted to perform beam steering). Antenna diversity schemes may also be used to ensure that antennas that have become blocked or that are otherwise degraded due to the operating environment of device  10  can be switched out of use and higher-performing antennas used in their place. 
     As shown in  FIG. 3 , transceiver circuitry  20  in wireless communications circuitry  34  may be coupled to antenna feed  42  on antenna  40  using radio-frequency transmission line  44 . Antenna feed  42  may include a positive antenna feed terminal such as positive antenna feed terminal  46  and may include a ground antenna feed terminal such as ground antenna feed terminal  48 . Transmission line  44  may be formed from metal traces on a printed circuit or other conductive structures and may have a positive transmission line signal path such as path  50  (sometimes referred to herein as signal conductor  50 ) that is coupled to terminal  46  and a ground transmission line signal path such as path  52  (sometimes referred to herein as ground conductor  52 ) that is coupled to terminal  48 . Other types of antenna feed arrangements may be used if desired. For example, antenna structures  40  may be fed using multiple feeds. The illustrative feeding configuration of  FIG. 3  is merely illustrative. 
     Transmission line paths such as transmission line  44  may be used to route antenna signals within device  10 . Transmission line  44  may include coaxial cable paths, microstrip transmission lines, stripline transmission lines, edge-coupled microstrip transmission lines, edge-coupled stripline transmission lines, transmission lines formed from combinations of transmission lines of these types, or any other desired radio-frequency transmission line structures. Filter circuitry, switching circuitry, impedance matching circuitry, and other circuitry may be coupled to antenna  40  (e.g., to support antenna tuning, to support operation in desired frequency bands, etc.). 
     Transmission line paths in device  10  such as transmission line  44  may be integrated into rigid and/or flexible printed circuit boards if desired. In one suitable arrangement, transmission line paths in device  10  may include transmission line conductors (e.g., signal and/or ground conductors) that are integrated within multilayer laminated structures (e.g., layers of a conductive material such as copper and a dielectric material such as a resin that are laminated together without intervening adhesive) that may be folded or bent in multiple dimensions (e.g., two or three dimensions) and that maintain a bent or folded shape after bending (e.g., the multilayer laminated structures may be folded into a particular three-dimensional shape to route around other device components and may be rigid enough to hold its shape after folding without being held in place by stiffeners or other structures). All of the multiple layers of the laminated structures may be batch laminated together (e.g., in a single pressing process) without adhesive (e.g., as opposed to performing multiple pressing processes to laminate multiple layers together with adhesive). Filter circuitry, switching circuitry, impedance matching circuitry, and other circuitry may be interposed within the transmission lines, if desired. 
     If desired, optional impedance matching circuitry  54  may be interposed on transmission line  44 . Impedance matching circuitry  54  may include fixed and/or tunable components. For example, circuitry  54  may include a tunable impedance matching network formed from components such as inductors, resistors, and capacitors that are used in matching the impedance of antenna structures  40  to the impedance of transmission line  44 . If desired, circuitry  54  may include a band pass filter, band stop filter, high pass filter, and/or low pass filter. Components in matching circuitry  54  may be provided as discrete components (e.g., surface mount technology components) or may be formed from housing structures, printed circuit board structures, traces on plastic supports, etc. In scenarios where matching circuitry  54  is adjustable, storage and processing circuitry  14  ( FIG. 2 ) may provide control signals that adjust the impedance provided by matching circuitry  54 , for example. Matching circuitry  54  and/or other tunable components coupled to antenna  40  may be adjusted (e.g., using control signals provided by control circuitry  14 ) to cover different desired communications bands. 
     If desired, one or more antennas  40  may be integrated within display  9  of  FIG. 1 . Antennas that are integrated within display  9  may include antenna structures formed from patterns of conductive traces in one or more conductive layers on a dielectric substrate.  FIG. 4  is a diagram showing how antenna  40  (e.g., an antenna integrated within display  9  of  FIG. 1 ) may be formed using patterns of conductive traces in one or more conductive layers on a dielectric substrate. 
     As shown in  FIG. 4 , wireless communications circuitry  34  may include conductive layers such as conductive layers  60  and  66 . Conductive layers  60  and  66  may be formed on a dielectric substrate (e.g., different surfaces of the same dielectric substrate). The dielectric substrate may include multiple stacked dielectric layers. The dielectric substrate may include a display module for display  9  ( FIG. 1 ) having stacked dielectric display layers, for example. 
     In one suitable arrangement, conductive layers  60  and  66  are formed on opposing sides of a given dielectric layer in the substrate. In another suitable arrangement, conductive layers  60  and  66  are formed on different dielectric layers in the substrate. Conductive layers  60  and  66  may be formed from metal traces, metal foil, stamped sheet metal, conductive coatings on the dielectric substrate, conductive portions of housing  12  ( FIG. 1 ), or any other desired conductive structures. Conductive layers  60  and  66  may include, for example, indium tin oxide (ITO), copper, aluminum, stainless steel, silver, gold, nickel, tin, other metals or metal alloys, or any other desired conductive materials. 
     Conductive layer  60  may include a region (portion)  64  that is patterned to form a grid or mesh of intersecting conductive traces. Region  64  may sometimes be referred to herein as grid  64  of conductive traces in conductive layer  60 , mesh  64  of conductive traces in conductive layer  60 , or pattern  64  of conductive traces in conductive layer  60 . Grid  64  may include segments of conductive traces arranged in a grid or mesh pattern (e.g., segments of conductive traces arranged in array of crossing (intersecting) rows and columns and each surrounding openings in conductive layer  60 ). Grid  64  may be separated from conductive material within other regions (portions) of conductive layer  60  by gaps or openings in conductive layer  60 . 
     Antenna  40  may include antenna structures such as an antenna resonating element, an antenna ground, and antenna feed  42  ( FIG. 3 ). The antenna resonating element may be coupled to positive antenna feed terminal  46  whereas the antenna ground is coupled to ground antenna feed terminal  48 . The antenna resonating element may have dimensions (e.g., a particular shape, perimeter, and/or area) that support an antenna resonance within one or more desired frequency bands (e.g., for performing wireless communications in those frequency bands). 
     As shown in  FIG. 4 , positive antenna feed terminal  46  may be coupled to grid  64  in conductive layer  60  so that grid  64  forms the antenna resonating element for antenna  40 . Conductive layer  66  may include a region  70  that forms an antenna ground for antenna  40 . Region  70  may sometimes be referred to herein as antenna ground  70  or ground plane  70 . Antenna ground  70  may be separated from conductive material in other regions of conductive layer  66  by openings or gaps in conductive layer  66 . Ground antenna feed terminal  48  of antenna  40  may be coupled to antenna ground  70  in conductive layer  66 . 
     Grid  64  of conductive layer  60  may receive radio-frequency signals from transceiver circuitry  20  over positive antenna feed terminal  46 . Corresponding antenna currents may flow through the segments of conductive traces in grid  64 . Openings or gaps in conductive layer  60  may prevent the antenna currents from flowing to other portions of conductive layer  60  that are not a part of grid  64 . Antenna currents flowing through grid  64  and antenna ground  70  may generate wireless signals that are radiated by antenna  40 . Similarly, antenna  40  may receive wireless signals from external communications equipment. The received wireless signals may generate antenna currents on grid  64  and antenna ground  70  that are then conveyed to transceiver  20  over transmission line  44 . 
     The conductive material used to form conductive layers  60  and  66  may be substantially transparent. For example, in one suitable arrangement, conductive layers  60  and  66  include ITO traces that are substantially transparent at optical wavelengths. Openings in grid  64  may further increase the optical transparency of grid  64 . If desired, antenna ground  70  may be patterned using a grid of conductive traces similar to grid  64  of conductive layer  60 . This may, for example, further increase the optical transparency of antenna ground  70 . When configured in this way, conductive layers  60  and  66  and antenna  40  may be integrated into display  9  of device  10  ( FIG. 1 ) without being perceptible or easily discernable to a user while viewing display  9 , for example. 
     If desired, conductive layer  60  may include other regions (portions)  62  of conductive traces that are not used to form part of antenna  40 . Regions  62  may be separated from grid  64  by gaps or openings in conductive layer  60  to prevent antenna currents on grid  64  from shorting to regions  62 . Conductive traces in regions  62  may, for example, form display structures within display  9  of device  10  ( FIG. 1 ). Such display structures may include display pixel circuitry that emit display light, touch sensor electrodes that gather touch input from a user, or other components, as examples. 
     If desired, conductive layer  66  may include other regions (portions)  68  of conductive traces that are not used to form part of antenna  40 . Regions  68  may be separated from antenna ground  70  by gaps or openings in conductive layer  66  to prevent antenna currents on antenna ground  70  from shorting to regions  68 . Conductive traces in regions  68  may, for example, form display structures within display  9  of device  10  ( FIG. 1 ). Such display structures may include display pixel circuitry that emit display light, touch sensor electrodes that gather touch input from a user, or other components, as examples. In another suitable arrangement, antenna ground  70  extends across all of conductive layer  66 . 
     If desired, some or all of the conductive traces in grid  64  may be used to form display structures such as pixel circuitry and/or touch sensor electrodes for display  9  ( FIG. 1 ). Some or all of the conductive traces in antenna ground  70  may be used to form display structures such as pixel circuitry and/or touch sensor electrodes, if desired. The example of  FIG. 4  is merely illustrative. If desired, multiple grids  64  may be formed within conductive layer  60  and/or multiple antenna grounds  70  may be formed within conductive layer  66  (e.g., to integrate multiple antennas  40  within display  9  of  FIG. 1 ). 
       FIG. 5  is a perspective view showing a region  75  of conductive traces that may be used in forming grid  64  and/or antenna ground  70  of  FIG. 4 . As shown in  FIG. 5 , conductive layer  72  (e.g., a conductive layer such as conductive layers  60  or  66  of  FIG. 4 ) may be formed on a top surface of a dielectric substrate such as dielectric layer  78 . Dielectric layer  78  may be formed from plastic, polymer, glass, ceramic, epoxy, foam, a rigid or flexible printed circuit board substrate, or any other desired materials. Conductive layer  72  may include a conductive coating or metal coating, sheet metal, conductive or metal traces, or any other desired conductive structures formed on the top surface of dielectric layer  78 . In one suitable arrangement, conductive layer  72  is an ITO layer and the conductive material in conductive layer  72  is formed from ITO. 
     As shown in  FIG. 5 , conductive layer  72  may include a pattern of slots  76  (sometimes referred to as notches, gaps, openings, or holes  76 ) within region  75 . Each slot  76  may be completely surrounded by conductive material from conductive layer  72 . The conductive material surrounding slots  76  may form segments  74  of conductive traces in conductive layer  72  (sometimes referred to herein as conductive paths  74  or conductive traces  74 ). 
     Slots  76  may, for example, be arranged in an array. Conductive segments  74  may be arranged in a grid (mesh) pattern defining the edges of slots  76 . Each conductive segment  74  may have a first end coupled to three other segments  74  and a second end coupled to three other segments  74  (e.g., segments  74  may intersect other segments in region  75 ). Grid  64  of conductive layer  60  and/or antenna ground  70  of conductive layer  66  ( FIG. 4 ) may include slots  76  and corresponding segments  74  of conductive traces as shown in  FIG. 5  (e.g., region  75  may be used to implement grid  64  and/or antenna ground  70  of  FIG. 4 ). 
     Slots  76  may, for example, extend completely through the thickness of conductive layer  72 . Slots  76  may be filled with dielectric material, with an integral portion of the underlying dielectric layer  78 , or may be void of material. The dimensions of slots  76  and segments  74  may be selected to adjust the inductance of segments  74  and to tweak the radiating characteristics of antenna  40  ( FIG. 4 ). 
     Region  75  of conductive layer  72  may be described at least in part by two characteristics: the length  80  of each segment  74  of conductive traces (e.g., the width of slots  76  separating two parallel segments  74 ) and the width  82  of each segment  74  of conductive traces. In practice, shorter widths  82  and greater lengths  80  may increase the optical transparency of conductive layer  72  whereas greater widths  82  and shorter lengths  80  may increase the antenna efficiency for antenna  40  ( FIG. 4 ). In order to balance these effects, length  80  may be between 0.5 mm and 1.0 mm, between 0.2 mm and 1.2 mm, or between 0.1 mm and 5.0 mm, as examples. Width  82  may be between 0.01 mm and 0.20 mm, between 0.05 mm and 0.15 mm, between 0.05 mm and 0.10 mm, or any other desired width less than length  80  and greater than about 0.01 mm, as examples. 
     In the example of  FIG. 5 , slots  76  each have the same square shape and size. This is merely illustrative. Slots  76  may have any desired shape having straight and/or curved edges. For example, slots  76  may be triangular, rectangular, hexagonal, polygonal, circular, elliptical, etc. Similarly, segments  74  need not be arranged in a rectangular grid pattern (e.g., segments  74  may be arranged in a hexagonal grid or a triangular grid). In these scenarios, length  80  may be the length of the longest lateral dimension of slots  76  or the length of one of the sides of slots  76 . Slots  76  in region  75  need not all be the same size and shape and, if desired, region  75  may include slots  76  of multiple different sizes and/or shapes. 
     Region  75  of  FIG. 5  may be used to form grid  64  of conductive layer  60  (e.g., region  75  of  FIG. 5  may be used to form the antenna resonating element for antenna  40 ). Antenna  40  may include any desired type of antenna having any desired type of antenna resonating element. Region  75  of  FIG. 5  may, for example, be used to form a patch antenna resonating element, a dipole antenna resonating element, a monopole antenna resonating element, a loop antenna resonating element, an inverted-F antenna resonating element, a planar inverted-F antenna resonating element, or any other desired antenna resonating elements for antenna  40 . 
       FIG. 6  is a schematic diagram showing how antenna  40  may be implemented as a patch antenna. As shown in  FIG. 6 , antenna  40  may include a patch antenna resonating element  84  that is separated from and parallel to a ground plane such as ground plane  86 . Arm  94  may be coupled between patch antenna resonating element  84  and positive antenna feed terminal  46  of antenna feed  42 . Ground antenna feed terminal  48  may be coupled to ground plane  86 . Patch antenna resonating element  84  may be separated from ground plane  86  by distance  89 . Patch antenna resonating element  84  may sometimes be referred to herein as patch element  84 , patch radiating element  84 , or patch  84 . 
     If desired, impedance matching notches  92  may be formed in patch element  84  to help match the impedance of patch element  84  to the impedance of transmission line  44  ( FIG. 3 ). The length  88  of the sides of patch element  84  may be selected so that antenna  40  resonates at a desired operating frequency. For example, length  88  may be approximately equal to one-half of the wavelength corresponding to the operating frequency for antenna  40  (e.g., an effective wavelength that accounts for dielectric loading by dielectric material between patch element  84  and ground plane  86 ). 
     The example of  FIG. 6  is merely illustrative. If desired, patch element  84  may have different shapes and orientations (e.g., planar shapes, curved patch shapes, patch element shapes with non-rectangular outlines, shapes with straight edges such as squares, shapes with curved edges such as ovals and circles, shapes with combinations of curved and straight edges, etc.). Antenna  40  may be provided with multiple antenna feeds for covering multiple polarizations if desired. 
       FIG. 7  is a perspective view showing how a patch antenna of the type shown in  FIG. 6  may be formed using conductive layers  60  and  70  of  FIG. 4 . As shown in  FIG. 7 , antenna  40  may include grid  64  of conductive traces in conductive layer  60 . Conductive layer  60  may be formed on a top surface of dielectric layer  78 . Grid  64  may include segments  74  of conductive traces arranged in a grid pattern and surrounding slots  76 . 
     Grid  64  may form the antenna resonating element (e.g., patch element  84  of  FIG. 6 ) for antenna  40 . Grid  64  may have edges that define the outline of the antenna resonating element. Grid  64  may have sides of length  88  to define the resonating frequencies for antenna  40 . Positive antenna feed terminal  46  may be coupled to a segment  74  of conductive traces in arm  94  of the antenna resonating element. 
     Antenna ground  70  may be formed from conductive traces at the bottom surface of dielectric layer  78 . Antenna ground  70  may include a grid pattern of segments  74  and slots  76  if desired. Antenna ground  70  may form ground plane  86  ( FIG. 6 ) for antenna  40 . Ground antenna feed terminal  48  may be coupled to antenna ground  70 . 
     Other regions of conductive layer  60  (e.g., regions  62  of  FIG. 4 ) may be formed on the top surface of dielectric layer  78 . These regions are not shown in  FIG. 7  for the sake of clarity. Antenna current conveyed by positive antenna feed terminal  46  may pass through segments  74  of conductive traces in grid  64 . The antenna current may flow around the edges of grid  64  to radiate wireless signals. The interior of grid  64  (e.g., the segments  74  and slots  76  within the edges of grid  64 ) may appear as a solid conductor to the antenna currents, for example. At the same time, grid  64  may be substantially transparent or invisible at optical wavelengths. 
     Dielectric layer  78  may have a thickness (height)  90 . Thickness  90  of dielectric layer  78  may be, for example, between 6 mm and 1 mm, between 5.5 mm and 2 mm, between 5 mm and 3 mm, less than 1 mm, between 0.1 mm and 2 mm, or greater than 6 mm (e.g., 1 cm, 5 cm, 10 cm, etc.). Conductive layer  60  may have a thickness (e.g., parallel to the Z-axis of  FIG. 7 ) of between 100 nm and 10 nm, between 75 nm and 25 nm, less than 25 nm, greater than 100 nm, between 0.1 mm and 0.5 mm, between 500 microns and 1 mm, between 1 and 500 microns, or greater than 1 mm, as examples. 
     The example of  FIG. 7  is merely illustrative. Antenna  40  may be implemented using any desired antenna structures. Multiple dielectric layers may be used to separate antenna ground  70  from conductive layer  60 . Antenna  40  may be integrated within display  9  of  FIG. 1  without obstructing images displayed by display  9 . 
       FIG. 8  is a cross-sectional side view showing how antenna  40  may be integrated within a dielectric substrate such as a display module for display  9  ( FIG. 1 ). The plane of the page of  FIG. 8  may, for example, lie in the X-Z plane of  FIG. 7 . 
     As shown in  FIG. 8 , device  10  may include a dielectric substrate such as dielectric substrate  102 . Dielectric substrate  102  may be, for example, a rigid or flexible printed circuit board or other dielectric substrate. Substrate  102  may include multiple stacked dielectric layers (e.g., multiple layers of printed circuit board substrate such as multiple layers of fiberglass-filled epoxy) or may include a single dielectric layer. Substrate  102  may include any desired dielectric materials such as epoxy, plastic, ceramic, glass, foam, or other materials. 
     In the example of  FIG. 8 , substrate  102  includes multiple stacked dielectric layers  104  (e.g., a first layer  104 - 1 , a second layer  104 - 2 , a third layer  104 - 3 , a fourth layer  104 - 4 , etc.). Substrate  102  may form a part of display  9  of  FIG. 1  and may therefore sometimes be referred to herein as display module  102  or display stack  102 . 
     As shown in  FIG. 8 , substrate  102  may be mounted to an interior surface  98  of dielectric cover layer  96 . Dielectric cover layer  96  may form a portion of rear wall  12 R or sidewalls  12 W of device  10  ( FIG. 1 ), as examples. Dielectric cover layer  96  may have an exterior surface  100  that forms an external surface for device  10 . In scenarios where substrate  102  forms a part of display  9  ( FIG. 1 ), dielectric cover layer  96  may be a display cover layer that covers display  9  (e.g., that extends across substantially all of the front face of device  10 ). 
     Dielectric cover layer  96  may be a clear layer of plastic, glass, sapphire, or other materials. If desired, an opaque masking layer such as an ink layer may be formed at interior surface  98  of dielectric cover layer  96  (e.g., in scenarios where dielectric cover layer  96  is transparent). Display structures may be formed on dielectric substrate  102 . The display structures may produce images for a user (e.g., images that are displayed through dielectric cover layer  96 ) and may receive touch input from a user (e.g., in response to touch or force applied to exterior surface  100  of dielectric cover layer  96 ). 
     Display structures in dielectric substrate  102  may include liquid crystal display structures, electrophoretic display structures, light-emitting diode display structures such as organic light-emitting diode display structures, or other suitable display structures. Dielectric layers  104  in substrate  102  may include layers of backlight structures, layers of light guide structures, layers of light source structures such as layers that include an array of light-emitting diodes or other display pixel circuitry, light reflector structures, optical films, diffuser layers, light collimating layers, polarizer layers, planarization layers, liquid crystal layers, color filter layers, thin-film transistor layers, optically transparent substrate layers, optically opaque substrate layers, layers for forming touch sensor electrodes associated with touch sensing capabilities for display  9  (in scenarios where display  9  is a touch sensor), birefringent compensating films, antireflection coatings, scratch prevention coatings, oleophobic coatings, layers of adhesive, stretched polymer layers such as stretched polyvinyl alcohol layers, tri-acetyl cellulose layers, antiglare layers, plastic layers, and/or any other desired layers used to form display structures for displaying images to a user of device  10  and/or for receiving a touch or force input from a user of device  10 . 
     Some dielectric layers  104  may be used to form pixel circuitry for displaying images while other dielectric layers  104  are used to form touch sensor electrodes for gathering touch sensor input, in one example. The touch sensor electrodes may include an array of capacitive electrodes (e.g., transparent electrodes such as indium tin oxide electrodes) or may include a touch sensor array based on other touch technologies (e.g., resistive touch sensor structures, acoustic touch sensor structures, piezoelectric sensors and other force sensor structures, etc.). 
     Antenna  40  may be partially or completely embedded within substrate  102 . Conductive layer  60  for forming the antenna resonating element of antenna  40  ( FIG. 7 ) may be formed on any desired layers  104  in substrate  102 . For example, conductive layer  60  may be formed on an upper lateral surface of layer  104 - 1  (e.g., layer  104 - 1  may serve as dielectric layer  78  of  FIG. 7 ). In this scenario, grid  64  ( FIGS. 4 and 7 ) may be formed at location  110  of  FIG. 8 . Conductive layer  60  may directly contact dielectric cover layer  96  or may be coupled to dielectric cover layer  96  using adhesive. If desired, conductive layer  60  may be patterned directly onto dielectric cover layer  96  before affixing dielectric cover layer  96  to substrate  102 . 
     As another example, conductive layer  60  may be formed on an upper lateral surface of layer  104 - 2  (e.g., conductive layer  60  may be embedded within the layers of substrate  102  and layer  104 - 2  may serve as dielectric layer  78  of  FIG. 7 ). In this scenario, grid  64  may be formed at location  106  of  FIG. 8 . In yet another example, conductive layer  60  may be formed on an upper lateral surface of layer  104 - 3  (e.g., layer  104 - 3  may serve as dielectric layer  78  of  FIG. 7 ). In this scenario, grid  64  may be formed at location  108  of  FIG. 8 . In general, locations that are closer to dielectric cover layer  96  may offer improved isolation and antenna efficiency relative to locations that are farther from dielectric cover layer  96 . These examples are merely illustrative and, in general, conductive layer  60  may be formed on any desired layer  104  within substrate  102  and at any desired location across the lateral area of substrate  102  (e.g., at locations such as locations  6  and  8  of  FIG. 1 ). Grid  64  may extend some or all of the underlying layer if desired. Multiple antennas may be formed from multiple conductive layers on multiple dielectric layers  104  if desired. Multiple antennas may be formed from conductive layers on the same dielectric layer  104  if desired. Antenna ground  70  ( FIG. 7 ) may be formed on any desired dielectric layer  104  of substrate  102  below conductive layer  60 . 
     When arranged in this way, antenna  40  may convey radio-frequency signals  112  through dielectric cover layer  96 . Grid  64  may be formed within the same conductive layer (e.g., conductive layer  60  of  FIGS. 4 and 7 ) as pixel circuitry and/or touch sensor electrodes in display  9  ( FIG. 1 ). If desired, some or all of grid  64  may also be used to form pixel circuitry and/or touch sensor electrodes in display  9 . Grid  64  may be substantially transparent at optical wavelengths. By forming the antenna resonating element for antenna  40  using the same conductive layers as other display components in substrate  102 , the same manufacturing process (e.g., an ITO deposition process) may be used to form both antenna  40  and the display structures within substrate  102 . This may minimize manufacturing complexity and cost relative to scenarios where antenna  40  is otherwise attached to substrate  102 , for example. 
     Antenna  40  embedded in substrate  102  may be fed using any desired antenna feed structures.  FIGS. 9-11  are cross sectional side views showing how antenna  40  may be provided with different feed arrangements within substrate  102  of  FIG. 8 . In the example of  FIG. 9 , antenna  40  is directly fed using a conductive via. 
     As shown in  FIG. 9 , conductive layer  60  may be formed on dielectric layer  114  whereas antenna ground  70  is formed on dielectric layer  116  of substrate  102 . Dielectric layers  114  and  116  may be different dielectric layers  104  as shown in  FIG. 8 , for example. This example is merely illustrative and, if desired, additional dielectric layers may be interposed between conductive layer  60  and antenna ground  70 . 
     Grid  64  in conductive layer  60  may form the antenna resonating element for antenna  40  (e.g., patch element  84  of  FIG. 6 ). Grid  64  may be separated from regions  62  of conductive layer  60  that are not used to form part of antenna  40  by gaps such as gap  115 . Regions  62  may be used to form pixel circuitry and/or touch sensor electrodes, as an example. An opening such as hole  118  may be formed in antenna ground  70 . A conductive through-via such as conductive via  119  may extend through layer  116 , hole  118 , and layer  114  to positive antenna feed terminal  46  on grid  64 . Conductive via  119  may form a part of the signal conductor for the transmission line  44  ( FIG. 3 ) used to feed antenna  40 . Feeding antenna  40  using conductive via  119  may allow grid  64  to be located at any desired location within the lateral area of substrate  102  (e.g., grid  64  need not be located at the periphery of substrate  102  to receive radio-frequency signals from the transceiver circuitry). 
     In the example of  FIG. 10 , antenna  40  is directly fed using a flexible printed circuit. As shown in  FIG. 10 , conductive layer  60  may be formed on dielectric layer  122  whereas antenna ground  70  is formed on dielectric layer  120  of substrate  102 . Dielectric layers  122  and  120  may be different dielectric layers  104  as shown in  FIG. 8 , for example. This example is merely illustrative and, if desired, additional dielectric layers may be interposed between conductive layer  60  and antenna ground  70 . 
     Conductive traces on flexible printed circuit  124  may be coupled to positive antenna feed terminal  46  and ground antenna feed terminal  48  of antenna  40 . Signal conductor  50  and ground conductor  52  of radio-frequency transmission line  44  ( FIG. 3 ) may be formed from conductive traces on flexible printed circuit  124 , for example. Flexible printed circuit  124  may be coupled to a side of substrate  102  and may extend to a main logic board within the interior of device  10 . Conductive traces on flexible printed circuit  124  may be used to convey touch signals generated by touch sensor electrodes (e.g., within region  62  of conductive layer  60  or elsewhere in substrate  102 ) to circuitry on the main logic board. If desired, conductive traces on flexible printed circuit  124  may be used to convey image data to pixel circuitry on substrate  102 . In this way, the same substrate (e.g., flexible printed circuit  124 ) may be used to convey signals for both the display structures and the antenna in substrate  102 , thereby optimizing space consumption within device  10 . 
     In the example of  FIG. 11 , antenna  40  is indirectly fed using an indirect antenna feed element. As shown in  FIG. 11 , conductive layer  60  may be formed on dielectric layer  126  whereas antenna ground  70  is formed on dielectric layer  130  of substrate  102 . At least one dielectric layer such as dielectric layer  128  may be interposed between dielectric layers  126  and  130 . Dielectric layers  130 ,  128 , and  126  may be different dielectric layers  104  as shown in FIG.  8 , for example. 
     Additional conductive traces such as conductive trace  132  may be formed on dielectric layer  128 . Conductive trace  132  may be formed from ITO, as an example. An opening such as hole  135  may be formed in antenna ground  70 . A conductive through-via such as conductive via  135  may extend through layer  130 , hole  135 , and layer  128  to positive antenna feed terminal  46  on conductive trace  132 . Conductive via  134  may form a part of the signal conductor for the transmission line  44  ( FIG. 3 ) used to feed antenna  40 . 
     Antenna currents may be conveyed over conductive via  134  and conductive trace  132 . Antenna currents flowing on antenna trace  132  may induce corresponding antenna currents on grid  64  in conductive layer  60  via near-field electromagnetic coupling  136 . Similarly, antenna currents generated on grid  64  by received radio-frequency signals may induce antenna currents on conductive trace  132 . In this way, conductive trace  132  may indirectly feed the antenna resonating element for antenna  40  (e.g., grid  64 ). Conductive trace  132  may sometimes be referred to herein as antenna feeding element  132 , indirect antenna feed element  132 , or antenna feed probe  132 . The example of  FIG. 11  is merely illustrative. If desired, flexible printed circuit  124  ( FIG. 10 ) may be coupled to positive antenna feed terminal  46  on conductive trace  132 . 
       FIG. 12  is a graph in which antenna performance (antenna efficiency) of antenna  40  has been plotted as a function of frequency. Curve  138  of  FIG. 12  plots the antenna efficiency of an antenna having an antenna resonating element formed from a solid conductor embedded within substrate  102  ( FIG. 8 ). As shown by curve  138 , the solid antenna resonating element exhibits a peak response at a frequency within frequency band  142 . The antenna efficiency exceeds a minimum antenna efficiency threshold TH across band  142 . 
     Curve  140  plots the antenna efficiency of antenna  40  having a resonating element formed using grid  64  (e.g., as shown in  FIGS. 4 and 7-11 ). As shown by curve  140 , forming the antenna resonating element using grid  64  slightly reduces the antenna efficiency across frequency band  142  (e.g., due to the presence of slots  76  as shown in  FIG. 5 ). However, antenna  40  still exhibits a satisfactory antenna efficiency greater than threshold level TH across frequency band  142 . As an example, curve  140  may include points that are only between 0 and 5 dB below curve  138 . Adjusting the dimensions of grid  64  (e.g., length  80  and/or width  82  of  FIG. 5 ) may tweak curve  140  but, in general, curve  140  may still exceed threshold TH across frequency band  142 . 
     Frequency band  142  may be any desired frequency band such as a GPS band centered at 1575 MHz, a 2.4 GHz WLAN band WL (e.g., extending between about 2400 MHz and 2500 MHz), a 5.0 GHz WLAN band WH (e.g., extending between about 5150 MHz and 5850 MHz), and cellular midband MB (e.g., a band extending between approximately 1700 MHz and 2200 MHz), etc. The example of  FIG. 12  is merely illustrative. Antenna  40  may exhibit any desired number of response peaks in any desired frequency bands (e.g., curve  140  may exhibit other shapes). 
     In this way, antenna  40  may be implemented within device  10  despite the relatively small form factor for device  10  and the presence of adjacent conductive components such as conductive structures used to form housing  12  ( FIG. 1 ). By embedding antenna  40  within display  9  ( FIG. 1 ), antenna  40  may be sufficiently isolated from other electronic components within device  10  and may exhibit satisfactory antenna efficiency across a frequency band of interest. Antenna  40  may be substantially transparent or invisible to the naked eye and may therefore overlap active portions of display  9  if desired. Forming antenna  40  using the same material as display structures in display  9  may simplify manufacturing complexity and minimize cost for manufacturing device  10 . Space within device  10  that would otherwise be occupied by antennas (e.g., space outside of display  9 ) may be used to accommodate any other desired device components. 
     The foregoing is merely illustrative and various modifications can be made to the described embodiments. The foregoing embodiments may be implemented individually or in any combination.

Metadata:
Filing Date: 20180711
Publication Date: 20200804
Grant Date: 20200804
Priority Date: 20180711
Inventors: YONG, Siwen
JIANG, YI
WU, JIANGFENG
ZHANG, LIJUN
PASCOLINI, MATTIA
Assignee: APPLE INC
CPC Classifications: [{"code": "H01Q21/005", "inventive": true, "first": false, "tree": "[]"}, {"code": "H01Q9/0407", "inventive": true, "first": false, "tree": "[]"}, {"code": "H01Q1/44", "inventive": true, "first": true, "tree": "[]"}, {"code": "H01Q1/38", "inventive": true, "first": true, "tree": "[]"}, {"code": "H01Q1/243", "inventive": true, "first": false, "tree": "[]"}, {"code": "H01Q1/22", "inventive": true, "first": false, "tree": "[]"}, {"code": "H01Q1/24", "inventive": true, "first": false, "tree": "[]"}, {"code": "H01Q1/243", "inventive": true, "first": true, "tree": "[]"}, {"code": "H01Q1/2258", "inventive": true, "first": false, "tree": "[]"}, {"code": "H01Q1/273", "inventive": true, "first": false, "tree": "[]"}, {"code": "H01Q1/38", "inventive": true, "first": false, "tree": "[]"}, {"code": "H01Q1/40", "inventive": true, "first": false, "tree": "[]"}, {"code": "H01Q1/243", "inventive": true, "first": true, "tree": "[]"}, {"code": "H01Q21/005", "inventive": true, "first": false, "tree": "[]"}]
Family ID: 69138801