Patent Description:
Some electronic devices have display modules that include a display and circuitry for causing information to appear on the display. Some of those electronic devices also have a display shield, which is a physical component that separates (or shields) components of the display module and forms part of an antenna, as disclosed in <CIT>, <CIT> and <CIT>.

The proposed solution relates to an electronic device, comprising a display module comprising a display; and an antenna, wherein the antenna comprises a display shield for the display of the device, the display shield separating display components for the display module from other electrical components of the device. The display shield is grounded to an enclosure of the device at least partially by one or more grounding clips, and the display shield is configured to receive and/or transmit radio frequency waves. According to a first aspect of the proposed solution, the antenna is a multiband antenna, wherein the display shield is conductively coupled to an antenna shorting pin that is coupled to an antenna tuning circuit on a main logic board for the device, and wherein the antenna tuning circuit is configured to tune the antenna to one of a plurality of frequency bands. According to a second aspect of the proposed solution (being independent from the first aspect), the display shield defines an aperture extended partially along the surface of the display shield, and the antenna is grounded by a flexible printed circuit tail passing through the aperture and coupling the display module with at least one other electrical component of the device.

The present disclosure thus provides for integrating an antenna into a display shield for devices having displays. The antenna is shaped as a display shield and functions as a radiating element and as an antenna. The display shield can separate components, such as a printed circuit board or a battery for a device, from other components. An antenna system including the display shield and one or more tuning circuits can be configured for tuning the display shield for multiband frequency transmission, and the display shield can be electrically isolated from the display module and electrically grounded to an enclosure for the device. At the same time, the display shield can be positioned in a device so as to not come in direct contact with the body of a user, for example when the device is a wearable device, such as a smartwatch.

This physical separation between the display shield and the user can mitigate interference from the body of the user, which can potentially arise from interfering body effects and/or the user's body physically blocking incoming and outgoing signals transmitted by the antenna. Examples of body effects can include shadowing, such as blocking the antenna from receiving signals, detuning, such as causing the frequency of the antenna to change, and attenuation, such as reducing the amplitude of incoming and/or outgoing signals.

The present disclosure provides examples of display shields for display modules, the display shields co-designed as antennas on electronic devices. For example, the electronic device can be a watch, a smartphone, an electronic reader, or any electronic device with a display. The display shield may function as a multiband antenna and can be configured to receive and/or transmit radio frequency waves. The display shield can be physically isolated from the body of a user when implemented as part of a wearable device.

The display shield can be a planar disc or other shape that can match or approximate the shape and size of a display for a device. The display shield is configured to support currents or fields that contribute directly to the radiation patterns of the antenna. The display shield can be made from any conductive material, such as from one or more metals or alloys. Other configurations for the display shield are possible and described in detail, herein. The display shield is grounded by clips attached to the display shield.

The display shield functions as an antenna as part of an antenna system for the device. The antenna system can include an antenna feed and a shorting pin that can provide electrical connection from the display shield to a radio chipset and antenna tuning circuitry. The radio chipset and antenna tuning circuitry can be components of the device and be physically separated by the display shield from a display module. The antenna tuning circuitry can tune the antenna system to receive and/or transmit radio frequency signals along a variety of different frequency bands through the display shield. The antenna tuning circuit and/or radio chipset can be implemented as part of a main logic board for the electronic device.

The display shield can sit partially within a device enclosure that houses different components, such as a battery or a main logic board. In some examples, the display shield can define an aperture for a flexible printed circuit tail or other electrical connector for connecting the different components of the electronic device with components of a display module. In some examples, the flexible printed circuit tail provides additional grounding for the display shield.

The antenna system can include a feed blade or spring clips for electrically connecting the display shield to an antenna tuning circuit. The antenna system can include multiple antenna tuning circuits electrically connected to the display shield through shorting blades, spring clips, or other types of connectors.

Aspects of the disclosure can provide for efficient operation of devices, particularly for small factor wearable electronic devices. The antenna system is arranged in the enclosure of a device to allow for physical distance between the antenna system and the body of a user operating the device, allowing for reduction of body effect and specific absorption rate. At the same time, the antenna system provided can allow for a relatively large antenna size, at least because the display shield acting as an antenna can be shaped and sized to be as large as a corresponding display for the device. The antenna system can be tuned for multiband performance across a variety of frequency bands corresponding to common wireless communication standards, such as cellular, UMTS (Universal Mobile Telecommunications System), Wi-Fi®, Bluetooth®, GPS, and Long-Term Evolution (LTE™) communication.

The display shield can be configured to receive and/or transmit radio frequency signals across a variety of different frequency bands, and can reduce or eliminate the need for additional elements in the physically constrained device to function as all or part of an antenna. Further, instead of implementing multiple antennas on a device already implementing a display shield, the display shield itself can be adaptively tuned to meet communication requirements across multiple frequency bands. Therefore, available physical space within the device can be more efficiently used, at least because the display shield is co-designed for protecting display components of a display module and while functioning as a multiband antenna.

The antenna system with display shield configured as described herein can be implemented across a variety of different devices, such as in smartwatches, tablets, personal computers, smartphones, and generally any device having a display. For wearable devices such as smartwatches, the antenna system can be implemented alongside a variety of different materials for securing the device onto the body of a user when worn. For example, the antenna system can perform robustly with various strap materials, such as metal, rubber, leather, or various kinds of textiles.

<FIG> illustrate an example display module with display shield, which can be part of an electronic device. The device can implement an antenna system that includes the display shield of the display module. The example electronic device can be a wearable device, for example a smartwatch. However, it should be understood that example antenna systems with display shields as described herein can be implemented in any of a variety of electronic devices with a display, including both wearable and non-wearable devices, such as smartphones, tablets, laptops, and televisions.

<FIG> illustrates an exploded view of an example display module <NUM> with a display shield <NUM> in accordance with aspects of the disclosure. The display module <NUM> can include display components <NUM> for implementing any of a variety of different displays. For example, the display module <NUM> can be a module for a liquid crystal display (LCD), light-emitting diode display (LED), an organic light-emitting diode display (oLED), a plastic organic light-emitting diode display (pOLED), or an electronic ink display. The display components <NUM> can include any component of the display module <NUM> sandwiched between the display shield <NUM> and a cover <NUM>.

Depending on the type of display implemented, the display components <NUM> can include components for implementing that type of display. For example, the display components <NUM> can include an emissive layer including light-emitting diodes on a substrate, and other components for passing current through the emissive layer. The display components <NUM> can be positioned behind the cover <NUM>, which may be glass, plastic, or generally any material that does not completely obscure an emissive layer for a display. In some examples, the emissive layer of the display components <NUM> can be laminated onto the cover <NUM>, or adhered to the cover <NUM> using a transparent adhesive material.

In some examples, the display components <NUM> can implement a display as a display panel including one or more emissive layers sandwiched between transparent panels of material such as glass or plastic. The display panel can include additional materials, such as polarizing films, filters, etc..

The display components <NUM> can include any of a variety of other components available on electronic devices with displays, such as a capacitive or resistive layer of material for receiving touch input to the display module <NUM>. The display module <NUM> can be configured for receiving and processing touch input, and emit image, text, or video. In some examples, the display components <NUM> can include an ambient light sensor (ALS) and be configured for receiving and processing signals received by the ALS. The display module <NUM> can be configured to, for example, adapt the brightness of the display based on the strength of light measured by the ALS. The display components <NUM> can be electrically connected to other components of an electronic device through a display flexible printed circuit (FPC) tail <NUM>. In some implementations, the display components <NUM> are electrically connected to other components of a device by wires, traces, or other conductive material.

The FPC tail <NUM> can pass electric signals to and from the display module <NUM> and other components, such as a battery or a main logic board, of an electronic device implementing the display module <NUM>. The display components <NUM> can also include exposed copper or other conductive material for anchoring one end of the display FPC tail <NUM> to the display components <NUM>. The FPC tail <NUM> can be made longer than necessary to connect the display components <NUM> to other components of the electronic device to allow for a service loop during device assembly. The display shield <NUM> can define an aperture <NUM> shaped and sized to allow the FPC tail <NUM> to pass through the display shield <NUM>.

The display shield <NUM> can physically separate the display components <NUM> from other components of an electronic device implementing the display module <NUM>. The display shield <NUM> can be made of a metal, or a conductive non-metal material, such as graphite. In some examples, the display shield is coated with a conductive material. The display shield <NUM> can be attached to the display components <NUM> with an adhesive layer <NUM> of material. The adhesive layer <NUM> of material can be, for example, pressure sensitive adhesive (PSA).

The display shield <NUM> can be substantially the same shape and size along a plane as a display for the display module <NUM>. For example, if the display module <NUM> has a circular display, the display shield can be of a circular shape and sized to sandwich the display components <NUM> with the cover <NUM>. The cover <NUM> can extend at least partially to sides <NUM> of the display module <NUM>, and the display shield <NUM> can be of a size and shape appropriate to fit flush with, or partially within, the cover <NUM>. In some implementations, the display shield <NUM> can be other shapes, such as rectangular, triangular, oblong, etc..

The display shield <NUM> can include one or more shield grounding clips <NUM>. In some examples, the shield grounding clips <NUM> can be affixed to a side of the display shield <NUM> that faces away from the display components <NUM>. In addition, the display shield <NUM> can include blade clips <NUM> that are formed to receive antenna blades electrically connecting the display shield <NUM> to other components of the electronic device, described herein. The blade clips <NUM> can be curved pieces of conductive material affixed to the display shield <NUM> and configured to hold a blade in place when inserted between the curved pieces. The blades can form electrical connections between the display shield <NUM> and other components of an antenna system, such as tuning circuitry and/or a radio chipset, described herein. The number of shield grounding clips <NUM> and blade clips <NUM>, as well as their position relative to one another, can vary depending on, for example, the position of other components of the electronic device.

<FIG> illustrates a perspective view of the example display module <NUM> with the display shield <NUM> and the display flexible printed circuit tail <NUM> in accordance with aspects of the disclosure. <FIG> illustrates the display shield <NUM> positioned partially within the cover <NUM>. In some implementations, the display shield <NUM> can be flush with the edges of the cover <NUM>, instead of positioned partially within the cover <NUM>. In <FIG>, the display components <NUM> of the display module <NUM> are hidden, because the display components <NUM> are sandwiched between the cover <NUM> and the display shield <NUM>. The display shield <NUM> may have a smooth surface or can be grooved at one or more locations to allow for extra space for the display components <NUM> when sandwiched between the cover <NUM> and the display shield <NUM>. The FPC tail <NUM> is also shown in <FIG> as passing through the display shield <NUM>.

<FIG> illustrates an exploded view of the example display module <NUM> with the display shield <NUM>, the cover <NUM>, and the display components <NUM> in accordance with aspects of the disclosure. The cover <NUM> can be shaped and sized to completely cover display <NUM>, so as to protect the display <NUM> from damage while still allowing contents of the display <NUM> to be seen. The cover <NUM> also allows touch input to be passed through the cover <NUM> and the display components <NUM>, in examples in which the display module <NUM> is configured to receive touch input. In <FIG>, the display module <NUM> is shown as including a near-field communication (NFC) module <NUM>. The NFC module <NUM> can be configured for receiving and transmitting data to and from other NFC-enabled devices.

The NFC module <NUM> can be positioned along the display shield <NUM>, which can act as a carrier to improve the performance of the NFC module <NUM>.

<FIG> illustrates a cross-sectional view of the example display module <NUM> with the display shield <NUM>, cover <NUM>, and display components <NUM> in accordance with aspects of the disclosure. As described with reference to <FIG>, the display shield <NUM> and the cover <NUM> can sandwich the display components <NUM>. Further, the display shield <NUM> can be positioned at least partially within the cover <NUM>, with the cover <NUM> extending at least partially over the sides <NUM> of the display module <NUM>. <FIG> also shows a gap <NUM> formed between the display shield <NUM> and the cover <NUM>. The display shield <NUM> can extend past the display components <NUM>, creating the gap <NUM> and allowing radio signal to pass through the gap <NUM> and improving signal quality at least by increasing overall surface area on the display shield <NUM> and by providing additional space for signals to pass.

<FIG> illustrates an exploded view of an antenna system <NUM> including the display shield <NUM> in accordance with aspects of the disclosure. The antenna system <NUM> can be implemented as part of an electronic device having a display, such as a smartwatch. The antenna system <NUM> can include the display shield <NUM>, a shorting blade <NUM>, antenna tuning circuits 206A-B, a feed blade <NUM>, and radio chipset <NUM>.

The antenna tuning circuits 206A-B and the radio chipset <NUM> can be positioned on a main logic board <NUM> for the electronic device. The main logic board <NUM> can be positioned in an enclosure <NUM>. Other components of the electronic device, such as a battery, can also be positioned within the enclosure <NUM> and be separated from the display components <NUM> by the display shield <NUM>. The enclosure <NUM> may further be adapted to modularly attach to other components. For example as shown, where the device is a smartwatch, the enclosure <NUM> may be adapted to attach to a watch band. The watch band may be made of any appropriate material, including metal, ceramic, leather, polymers, fabric, etc..

The enclosure <NUM> itself can be a housing for the electronic device. The enclosure <NUM> can be made of a conductive material or coated with a material, such as metal or plastic, and the display shield <NUM> can form a ground connection with the enclosure <NUM> through the shield grounding clips <NUM>.

The display shield <NUM> can act as a radiating element configured for receiving and sending out radio frequency signals at different frequencies. The feed blade <NUM> can electrically connect the display shield <NUM> to the radio chipset <NUM>. The radio chipset <NUM> can include one or more circuits configured for receiving incoming radio frequency signals from the display shield <NUM>, and sending outgoing radio frequency signals to the display shield <NUM> for transmittal. The radio chipset can function as a cellular modem, and be configured to receive and send cellular signals, as well as signals across a variety of different frequency bandwidth, as described herein. The feed blade <NUM> can be connected to the display shield by coupling with the blade clips <NUM>.

In some implementations, the feed blade <NUM> can be attached to the display shield <NUM> in other ways, such as being directly attached to the display shield <NUM> without the use of the blade clips <NUM>. The radio chipset <NUM> can be integrated as part of the main logic board <NUM>. In some implementations, the radio chipset <NUM> is a separate component of the electronic device that can be coupled to the main logic board <NUM>, for example using a wire or conductive trace.

The antenna system <NUM> can include a tuning circuit 206A electrically connected between the radio chipset <NUM> and the feed blade <NUM>. The feed blade <NUM> can be connected to the display shield <NUM> through the blade clips <NUM>. In general, the tuning circuit 206A can be configured for tuning the resonant frequency of the display shield <NUM> for operating according to a variety of different frequency bands. For example, the antenna system <NUM> can be configured to operate in different frequencies commonly associated with the LTE® communication standards, including low-band frequency range between <NUM> and <NUM>, mid-band frequency range between <NUM> to <NUM>, and high-band frequency range between <NUM> and <NUM>.

Other frequency bands in which the antenna system <NUM> can perform include frequency ranges for GNSS frequency bands, which may include GPS frequency centered around <NUM>, GLONASS frequency between <NUM>-<NUM>, and BeiDou frequency centered around <NUM>. In addition or alternatively, the antenna system <NUM> can be tuned to operate in frequency ranges between <NUM> and <NUM> for Wi-Fi and Bluetooth signals. As such, the antenna system <NUM> may provide coverage of LTE communication bands, GPS communication bands, and coverage of Wi-Fi and Bluetooth communication bands.

The antenna system <NUM> can include multiple tuning circuits 206A-B, as shown, for further fine-tuning the resonant frequency of the display shield <NUM> within a frequency band. For example, the tuning circuit 206B can be electrically connected to the shorting blade <NUM>. The shorting blade <NUM> and blade clips 209A, 209B can be a shorting pin between the tuning circuit 206B and the main logic board <NUM> to the display shield <NUM>. The tuning circuit 206B can be configured to fine-tune the resonant frequency of the display shield <NUM> tuned by the tuning circuit 206A. In some implementations, the antenna system <NUM> can include more or fewer tuning circuits. For example, in some implementations, the antenna system <NUM> can include a single tuning circuit configured to tune the display shield according to a variety of different frequency bands. The tuning circuits 206A-B can improve frequency match, antenna efficiency, and reduce specific absorption rate.

Also in <FIG>, the display FPC tail <NUM> is shown and can further ground the display shield <NUM>, in addition to the grounding clips <NUM>. In some implementations, the display shield <NUM> can be grounded by only the grounding clips <NUM>, or only the display FPC tail <NUM>.

<FIG> are diagrams of various example antenna systems. For each of the <FIG>, a main logic board from an example electronic device implementing an example antenna system is shown from a top-down perspective. Recall from <FIG>, one possible arrangement can be that the main logic board <NUM> is positioned inside the enclosure <NUM> and electrically connected to the display shield <NUM> through the FPC tail <NUM> and the antenna blades <NUM>, <NUM>. In addition to the components shown with reference to <FIG>, main logic boards 301A-D can include other components, not shown. For example, the main logic boards 301A-D can include radio chipsets for receiving and processing radio frequency signals.

<FIG> is a diagram of a first example antenna system 300A in accordance with aspects of the disclosure. On a main logic board 301A, the first example antenna system can include a power source 302A, multiple grounding points 303A, tuning circuits 306A, shorting pin 307A, and antenna feed 309A. The tuning circuits 306A can also be grounded by grounding points 311A. The multiple grounding points 303A can ground the display shield, and can be positioned as far as physically possible on the main logic board 301A from the antenna feed 309A. In some implementations, the multiple grounding points 311A can also be placed in other positions relative to the antenna feed 309A and/or the tuning circuits 306A and the antenna feed 309A.

<FIG> is a diagram of a second example antenna system 300B in accordance with aspects of the disclosure. In <FIG>, main logic board 301B is rectangular in shape, which can correspond to the shape of other components of an electronic device, such as its display shield and display (not shown). As described herein, the size and shape of the display shield can vary in accordance with the size and shape of the enclosure. The main logic board 301B can be similarly shaped and sized to allow for larger distances, e.g., such as the distance between corners of the main logic board 301B, between ground points 303B and antenna feed 309B. The main logic board 301B can also include tuning circuits 306B, grounded by grounding points 311B. The main logic board 301B can also include a power source 302B and shorting pin 307B.

<FIG> is a diagram of a third example antenna system 300C in accordance with aspects of the disclosure. In the third example antenna system 300C, an antenna shorting pin 307C can be configured as a second antenna feed, in addition to antenna feed 309C. Adding a second antenna feed can potentially increase potential bandwidth range for the third example antenna system 300C, as well as improve transmission overall. Main logic board 301C can also include power sources 302C connected to tuning circuits 306C. The tuning circuits 306C can be grounded by grounding points 311C. Similar to the main logic boards 301A-B shown in <FIG>, the main logic board 301C can also include grounding points 311C for grounding the display shield (not shown).

Multiple feeds can also allow for distribution of the range of frequencies, allowing different feeds to be dedicated to receiving signals at different respective frequencies. Multiple feeds can also provide for rapid switching between feeds in response to different operations performed by the electronic device. For example, the device can be configured to perform operations that require transmission to both Bluetooth and Wi-Fi signals, which can each be assigned to a respective feed. The antenna system 300C can be configured to switch between feeds depending on which type of signal is required to perform a current operation. In some examples, the antenna system 300C with multiple antenna feeds can provide for concurrent execution of operations relying on signals from multiple frequencies.

<FIG> is a diagram of a fourth example antenna system 300D in accordance with aspects of the disclosure. In the fourth example antenna system 300D, the antenna shorting pin is removed altogether. In addition, the display shield is grounded by a single grounding point 303D on main logic board 301D. The grounding point 303D can be a FPC tail connecting the main logic board 301D to display components of a display module (not shown). The main logic board 301D can also include a power source 302D, antenna feed 309D, and tuning circuit 306D with grounding point 311D.

Although different specific variations are shown between the example antenna systems in <FIG>, it is understood that various implementations of the disclosed subject matter provide for example antenna systems with different characteristics. In one example, an example antenna system can have a second antenna feed as well as a single grounding point replaced by the FPC tail. In another example, the display shield and main logic board can be rectangular in shape and include multiple tuning circuits, with a shorting pin configured to function as an antenna feed.

<FIG> is a circuit diagram <NUM> for an example antenna system in accordance with aspects of the disclosure. An antenna feed <NUM> can couple the display shield to the rest of the circuitry, as shown in <FIG>. A power source <NUM> can be a battery or other source of power for the example antenna system, and can be connected to a circuit ground point <NUM>. The circuit diagram <NUM> also shows a matching circuit <NUM>, as well as tuning circuits <NUM>.

A matching circuit is an impedance transforming circuitry that ensures proper impedance matching by transforming either or both impedances of a radio source and a load. The matching circuit <NUM> may include components such as inductors and capacitors. For instance, the matching circuit <NUM> may increase or decrease impedance of the radio source to match an impedance of the first antenna. Alternatively or additionally, the matching circuit <NUM> may increase or decrease impedance of a display shield to match an impedance of the radio source.

The circuit diagram <NUM> also shows grounding points <NUM>, which can include shield grounding clips as shown with reference to <FIG>, <FIG>. As another example, one or more of the grounding points <NUM> can be the FPC tail <NUM>, as shown in <FIG>. The circuit diagram <NUM> is one possible arrangement of the various circuit elements provided herein, although it is understood that other configurations are possible, for example configurations corresponding to the example antenna systems shown and described with reference to <FIG>.

<FIG> is a graph <NUM> quantifying resonance of an example antenna system as the S11 parameter for the antenna system over the frequency at multiple frequency bands 530A-E. The y-axis <NUM> represents the S11 parameter of the antenna system, measured in decibels. The x-axis <NUM> represents the frequency of the antenna system, measured in megahertz. Frequency band 530A lies between <NUM> and <NUM> megahertz, commonly associated with the low-band LTE® standard. Frequency band 530B is centered around <NUM> megahertz, commonly associated with GPS frequency band. Frequency band 530C lies between <NUM> megahertz and <NUM> megahertz, commonly associated with the mid-band LTE® standard. Frequency band 530D lies between <NUM> megahertz and <NUM> megahertz, commonly associated with the Wi-Fi® and Bluetooth® communication standards. Frequency band 530E lies between <NUM> megahertz and <NUM> megahertz, commonly associated with the high-band LTE® standard.

Claim 1:
An electronic device, comprising:
a display module (<NUM>) comprising a display (<NUM>); and
an antenna, wherein the antenna comprises:
a display shield (<NUM>) for the display of the electronic device, the display shield separating display components (<NUM>) for the display module from other electrical components of the electronic device,
wherein the display shield is grounded to an enclosure (<NUM>) of the electronic device at least partially by one or more grounding clips (<NUM>), and wherein the display shield is configured to receive and/or transmit radio frequency waves, and
wherein
(a) the antenna is a multiband antenna, and wherein the display shield is conductively coupled to an antenna shorting pin (<NUM>, 109B; 307A; 307B; 307C) that is coupled to an antenna tuning circuit (206A-B, 306A, 306B, 306C, 306D) on a main logic board (<NUM>, 301A, 301B, 301C, 301D) of the electronic device, wherein the antenna tuning circuit is configured to tune the antenna to one of a plurality of frequency bands, and/or
(b) the display shield defines an aperture (<NUM>) extended partially along the surface of the display shield, and the antenna is grounded by a flexible printed circuit tail (<NUM>) passing through the aperture (<NUM>) and coupling the display module with at least one other electrical component of the electronic device