PATENT DOCUMENT

Publication Number: US-12169422-B2
Application Number: US-202217649787-A
Country: US
Kind Code: B2

Title: Self-retracting display device and techniques for protecting screen using drop detection

Abstract:
In some aspects, mobile devices with foldable and rollable displays can use a sensor to detect vertical acceleration with respect to the ground to determine if the mobile device has been dropped. If the sensor detects that the mobile device has been dropped the foldable device can fold or retract at least partially to afford protection from the fragile display from striking the ground. Even folding the display to an angle less than 180 degrees can afford some protection because the mobile device can strike edges of the mobile device instead of the display itself. In various embodiments, a rollable device can retract the display if predetermined acceleration limits are exceeded.

Claims:
What is claimed is: 
     
       1. An electronic device, comprising:
 a first display coupled to a second display via a hinged connection; 
 an acceleration sensor configured to detect a drop of the electronic device from a vertical acceleration of the electronic device exceeding a predetermined vertical acceleration threshold; and 
 a release mechanism operating with the hinged connection to automatically reduce an angle between the first display and the second display below a threshold angle without reducing the angle between the first display and the second display to zero degrees when the predetermined vertical acceleration threshold is exceeded. 
 
     
     
       2. The electronic device of  claim 1 , wherein the release mechanism comprises a motorized hinge. 
     
     
       3. The electronic device of  claim 1 , wherein the release mechanism comprises a mechanical hinge with a spring-loaded detent. 
     
     
       4. The electronic device of  claim 1 , wherein the threshold angle is less than 180 degrees. 
     
     
       5. The electronic device of  claim 1 , wherein the first display or the second display is an organic light emitting diode display. 
     
     
       6. The electronic device of  claim 1 , wherein the first display and the second display each comprise regions of a foldable display. 
     
     
       7. The electronic device of  claim 1 , wherein the acceleration sensor comprises an inertial measurement unit. 
     
     
       8. A method, comprising:
 detecting a drop of an electronic device from a vertical acceleration of the electronic device; 
 comparing a value of the vertical acceleration of the electronic device against a predetermined threshold; and 
 activating a release mechanism for a hinged connection between a first display and a second display of the electronic device when the value of the vertical acceleration exceeds the predetermined threshold, wherein the activating reduces an angle between the first display and the second display below a threshold angle without reducing the angle between the first display and the second display to zero degrees. 
 
     
     
       9. The method of  claim 8 , wherein the release mechanism comprises a motorized hinge. 
     
     
       10. The method of  claim 8 , wherein the release mechanism comprises a mechanical hinge with a spring-loaded detent. 
     
     
       11. The method of  claim 8 , wherein the threshold angle is less than 180 degrees. 
     
     
       12. The method of  claim 8 , wherein the first display or the second display is an organic light emitting diode display. 
     
     
       13. The method of  claim 8 , wherein the first display and the second display each comprise regions of a foldable display.

Description:
CROSS-REFERENCES TO RELATED APPLICATIONS 
     This application claims priority to and the benefit of U.S. Provisional Patent Application No. 63/244,131, filed Sep. 14, 2021, entitled “Self-Retracting Display Device And Techniques For Protecting Screen Using Drop Detection” hereby incorporated by reference it in their entirety and for all purposes. 
    
    
     BACKGROUND 
     Mobile devices with thin-screen displays may be vulnerable if the display strikes the ground after dropping. Certain foldable displays and rollable displays can be especially vulnerable due to use of ultra-thin glass displays which can be especially vulnerable. It would be advantageous to detect when a device is falling to implement protection features to 
     BRIEF SUMMARY 
     Mobile devices with foldable and rollable displays can use a sensor to detect vertical acceleration (e.g., acceleration with respect to the ground) to determine if the mobile device has been dropped. If the sensor detects that the mobile device has been dropped the foldable device can retract at least partially to afford protection from the fragile display from striking the ground. Even folding the display to an angle less than 180 degrees can afford some protection because the mobile device can strike edges of the mobile device instead of the display itself. In various embodiments, a rollable device can retract the display if predetermined acceleration limits are exceeded. 
     In an aspect an electronic device can include a first display coupled to a second display via a hinged connection. In various embodiments, the first display and the second display can each be portions of a foldable display. The sensor used to detect vertical acceleration can be an accelerometer (e.g., as part of an inertial measure unit (IMU)). If the vertical acceleration exceeds a predetermined threshold, a release mechanism operating with a hinged connection can be used to reduce the angle between the first display and the second display below a threshold angle when the predetermined acceleration threshold is exceeded. In various embodiments, the threshold angle can be less than 180 degrees. 
     In various embodiments, the release mechanism can include a motorized hinge. In other embodiments, the release mechanism can include a mechanical hinge with a spring-loaded detent. 
     The first display or the second display can be a light emitting diode display such as an organic light emitting diode display. 
     In an aspect, an electronic device can include a foldable display coupled on one edge of the foldable device to a roller. The electronic device can include an acceleration sensor configured to detect a vertical acceleration of the electronic device exceeding a predetermined vertical acceleration threshold. The acceleration sensor can be an inertial measurement unit. The electronic device can include a release mechanism operating with the roller to automatically retract the foldable display on the roller when the detected vertical acceleration exceeds a predetermined acceleration threshold. 
     In various embodiments, the release mechanism comprises a motorized hinge. In other embodiments, the release mechanism comprises a mechanical hinge with a spring-loaded detent. 
     In various embodiments the foldable display can include a substrate including a first side and a second side, a first wiring layer on the first side, an array of LEDs on and in electrical contact with the first wiring layer on the first side of the substrate, and a second wiring layer on the second side of the substrate. The array of LEDs can include both inorganic LEDs and organic LEDs. The foldable display can include a plurality of interconnects extending between and electrically connecting the first wiring layer to the second wiring layer. 
     In various embodiments, the foldable display can include an array of microchips connected with the first wiring layer to drive the array of LEDs. Each microchip can be connected with a corresponding plurality of LEDs. 
     In an aspect, a method can include detecting a vertical acceleration of an electronic device. The method can include comparing a value of the vertical acceleration of the electronic device against a predetermined threshold. The method can include activating a release mechanism for a hinged connection between a first display and a second display of the electronic device when the vertical acceleration exceeds a predetermined threshold, wherein the activating reduces an angle between the first display and the second display below a threshold angle. 
     In various embodiments, the release mechanism comprises a motorized hinge. In various embodiments, the release mechanism comprises a mechanical hinge with a spring-loaded detent. 
     In various embodiments, the threshold angle is less than 180 degrees. In various embodiments, the first display or the second display is an organic light emitting diode display. The first display and the second display can each comprise regions of a foldable display. 
     A better understanding of the nature and advantages of embodiments of the present disclosure may be gained with reference to the following detailed description and the accompanying drawings. 
    
    
     
       BRIEF DESCRIPTION OF THE DRAWINGS 
         FIG.  1    is a perspective view of an illustrative electronic device in accordance with an embodiment. 
         FIG.  2    is a schematic diagram of an illustrative electronic device in accordance with an embodiment. 
         FIG.  3    is a diagram of a pair of adjacent electronic devices in accordance with an embodiment. 
         FIG.  4    is a side view of a pair of electronic devices supported by a bendable case with an internal hinge structure in accordance with an embodiment. 
         FIG.  5    is a side view of a pair of electronic devices supported by a folded case in accordance with an embodiment. 
         FIG.  6    is a side view of a pair of electronic devices in a case that has been folded back on itself in accordance with an embodiment. 
         FIG.  7    is a cross-sectional side view of a pair of illustrative electronic devices with beveled housing sidewalls that have been joined at a desired angle with respect to each other using magnetic attraction and the angled surfaces of the sidewalls in accordance with an embodiment. 
         FIG.  8    is a cross-sectional side view of the pair of electronic devices with beveled housing sidewalls of  FIG.  7    in a planar configuration in accordance with an embodiment. 
         FIG.  9    is a cross-sectional side view of a pair of illustrative electronic devices with angled housing sidewalls that have been joined at a desired angle with respect to each other using magnetic attraction in accordance with an embodiment. 
         FIG.  10    is a cross-sectional side view of the pair of illustrative electronic devices of  FIG.  9    in a planar orientation in accordance with an embodiment. 
         FIG.  11    is a cross-sectional side view of a pair of adjacent electronic devices each of which has a display that covers housing sidewalls in accordance with an embodiment. 
         FIG.  12    is a cross-sectional side view of a pair of adjacent electronic devices each of which has a display that is borderless along at least its left and right edges in accordance with an embodiment. 
         FIG.  13    is a diagram showing how a system with multiple electronic devices may present content to a user in various contexts in accordance with an embodiment. 
         FIG.  14    is a cross-sectional side view of a system in which two devices are in a face-to-face configuration in accordance with an embodiment. 
         FIG.  15    is a cross-sectional side view of a system in which two devices are in a back-to-back configuration in accordance with an embodiment. 
         FIG.  16    is a cross-sectional side view of a system in which two devices are in a back-to-front configuration in accordance with an embodiment. 
         FIG.  17    is a flow chart of illustrative operations involved in using multiple electronic devices in accordance with an embodiment. 
         FIG.  18    is a perspective view of an illustrative electronic device having a display in accordance with an embodiment. 
         FIG.  19    is a first cross-sectional side view of electronic devices with flexible displays in accordance with an embodiment. 
         FIG.  20    is a second cross-sectional side view of electronic devices with flexible displays in accordance with an embodiment. 
         FIG.  21    is a diagram of an illustrative display with an array of light-emitting pixels in accordance with an embodiment. 
         FIG.  22    is a display in which pixels overlapping a bend axis have been illuminate to heat the portion of the display overlapping the bend axis in accordance with an embodiment. 
         FIG.  23    is a cross-sectional side view of a portion of an electronic device with an electrically adjustable magnetic latching mechanism in accordance with an embodiment. 
         FIG.  24    is a cross-sectional side view of a portion of an electronic device with an illustrative electrically adjustable mechanical latching mechanism in accordance with an embodiment. 
         FIG.  25    is an exemplary embodiment of a device with a foldable display incorporating display protective features. 
         FIG.  26 A  is an exemplary embodiment of a device with a motorized release mechanism. 
         FIG.  26 B  is an exemplary embodiment of a device with a spring-loaded detent release mechanism. 
         FIG.  27    is a diagram of a device having one or more electronic flexible screens. 
         FIG.  28    is schematic cross-sectional side view illustration of a system including a flexible display panel secured to a spool in accordance with an embodiment of the invention. 
         FIG.  29    illustrates an exemplary device with a rollable display in which the display is extended. 
         FIG.  30    illustrates an exemplary device with a rollable display in which the display is retracted. 
         FIG.  31    is a flowchart of an example process associated with techniques to protect a display of an electronic device. 
         FIG.  32    is a block diagram of an example electronic device. 
     
    
    
     Like reference, symbols in the various drawings indicate like elements, in accordance with certain example implementations. In addition, multiple instances of an element may be indicated by following a first number for the element with a letter or a hyphen and a second number. 
     DETAILED DESCRIPTION 
     Modern mobile devices can include foldable or rollable displays. In various embodiments, the foldable display can include two screens coupled together via a hinged connection that can be operated together to form a larger display. In various embodiments, the display can be constructed from flexible materials that can be flexed about a bend axis. 
     An illustrative electronic device of the type that may be used in a system with multiple electronic devices is shown in  FIG.  1   . 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 smart phone, a media player, or other handheld or portable electronic device, a smaller device such as a wrist-watch 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 smart phone, cellular telephone, media player, tablet computer, or other portable computing device. 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  has opposing front and rear faces and peripheral sidewalls that run around the periphery of device  10 . Device  10  includes a display such as display  14  on the front face of device  10  mounted in 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 vertical sidewalls, curved sidewalls, sidewalls with one or more beveled (angled) portions, sidewalls that are uncovered by display  14 , sidewalls that are partly or fully covered by portions of display  14 , and/or other suitable sidewall structures. The rear face of device  10  may be covered with housing  12 . Configurations in which a display such as display  14  is formed on the rear face of housing  12  (e.g., in addition to display  14  on the front face of device  10 ) may also be used. 
     Display  14  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  14  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 display pixels or other light-emitting diodes, an array of electrowetting display pixels, or display pixels based on other display technologies. 
     Display  14  may be protected using a display cover layer such as a layer of transparent glass or clear plastic. Openings may be formed in the display cover layer. For example, an opening may be formed in the display cover layer to accommodate optional speaker port  18 . Openings may also be formed in housing  12  to form communications ports (e.g., an audio jack port, a digital data port, etc.), to form openings for buttons, etc. If desired, a touch sensor, fingerprint sensor, dome-switch button or other input device such as input device  16  may be formed on the front face of device  10  (e.g., within an opening in the display cover layer, under the display cover layer in a configuration in which the display cover layer does not contain any button openings, etc.). 
     Display  14  may have an active area and an inactive area. The active area may, as an example, be formed in a rectangular central portion of the front face of device  10 . The active area contains pixels that display images for a user of device  10 . Inactive border regions (areas without pixels) may be formed along one or more of the edges of the active area. For example, the active area may be bordered on the left and right and top and bottom by inactive display areas. In other configurations, the active area of display  14  may cover all of the front face of device  10 , may cover the front face of device  10  and some or all of the sidewalls of device  10 , may have inactive borders at the upper and lower ends of device  10  while being borderless along the left and right edges of device  10 , or may have other layouts. 
     Components such as light sensors (e.g., light-sensors in proximity sensors, ambient light sensors, etc.), cameras (e.g., digital image sensors that capture images), status indicator lights (e.g., light-emitting diodes), and other components may be mounted under windows in display  14  such as windows  20  or other portions of device  10 . Sensors such as proximity sensor light sensors may be mounted under a layer of visible-light-blocking and infrared-light-transparent material. Sensors such as ambient light sensors and other components that use visible light such as cameras and status indicator lights may be mounted under windows that are transparent to visible light. Light-based components such as these may also be mounted on the rear face of device  10 , on device sidewalls, or in other portions of structures of device  10 . 
     A schematic diagram of an illustrative electronic device such as device  10  of  FIG.  1    is shown in  FIG.  2   . As shown in  FIG.  2   , electronic device  10  may have control circuitry  50 . Control circuitry  50  may include storage and processing circuitry for supporting the operation of device  10 . The storage and processing circuitry 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 control circuitry  50  may be used to control the operation of device  10  (e.g., to process sensor signals and other input and to control adjustable components such as a display, a heating element, etc.). The processing circuitry may be based on one or more microprocessors, microcontrollers, digital signal processors, baseband processors, power management units, audio chips, application specific integrated circuits, etc. 
     Input-output circuitry in device  10  such as input-output devices  52  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. As shown in  FIG.  2   , input-output devices  52  may include display  14 . Display  14  may be a touch screen that incorporates a two-dimensional touch sensor or may be insensitive to touch. A two-dimensional touch sensor for display  14  may be formed from an array of capacitive touch electrodes touch sensor or other touch sensor components (e.g., force sensors, resistive touch sensors, acoustic touch sensors, optical sensors, etc.). 
     Input-output devices  52  may include sensors  56 . Sensors  56  may include a capacitive proximity sensor, a light-based proximity sensor, a magnetic sensor, a force sensor such as a force sensor that gathers user input, a touch sensor for gathering user touch input, a temperature sensor, a pressure sensor, an ambient light sensor, a microphone or other sound sensor that gathers ambient noise measurements and user input such as voice commands, sensors for gathering data on device position and motion such as inertial measurement units that include accelerometers, compasses, and/or gyroscopes, and/or other sensors. 
     Input-output devices  52  may also include other components  54  such as buttons, joysticks, scrolling wheels, touch pads, key pads, keyboards, speakers, tone generators, vibrators, cameras, light-emitting diodes and other status indicators, data ports, etc. A user can control the operation of device  10  by supplying user input commands through input-output devices  52  and may receive status information and other output from device  10  using the output resources of input-output devices  52 . 
     Input-output devices  28  may include status-indicator lights (e.g., light-emitting diodes), light-emitting diodes for providing camera flash illumination and other light, buttons, joysticks, scrolling wheels, key pads, keyboards, audio components  34  such as microphones and speakers (e.g., an ear speaker located at an upper end of device  10  and/or one or more speaker-phone speakers at an opposing lower end of device  10  or elsewhere in device  10  that are used to play audio when device  10  is being held away from a user&#39;s head), tone generators, haptic devices such as vibrators, cameras such as camera  30  (e.g., front-facing and/or rear-facing cameras), sensors  32 , displays such as display  14 , and other input-output components that gather input and provide output from device  10 . Input-output devices  28  (e.g., sensors  32 ) may include touch sensors (e.g., stand-alone touch sensors for touch sensitive buttons and track pads and/or touch sensor panels that overlap display  14  and are used in gathering touch screen input from a user as selectable on-screen options are displayed on display  14 ). Sensors  32  may also include light sensors, orientation sensors (e.g., accelerometers, gyroscopes, compasses, and/or other components that can detect device motion and/or device orientation such as device orientation relative to the Earth), resistance sensors (e.g., sensors that can detect contact by a conductive sidewall of another device or other external object), switch-based sensors, capacitance sensors, proximity sensors (e.g., a capacitive proximity sensor and/or a light-based proximity sensor such as an infrared proximity sensor that makes proximity sensor measurements by emitting infrared light from an infrared light-emitting diode and measuring corresponding reflected light using an infrared light detector), magnetic sensors, force sensors (e.g., force sensors based on a capacitive force sensing arrangement, strain gauges, piezoelectric force sensors, and/or other transducers that convert force into electrical signals), gas pressure sensors (e.g., sensors for measuring air pressure), gas sensors (e.g., carbon dioxide sensors), particulate sensors, moisture sensors, a connector port sensor or other sensor that determines whether first device  10  is mounted in a dock, and other sensors and input-output components. 
     Control circuitry  50  may be used to run software on device  10  such as operating system code and applications. During operation of device  10 , the software running on control circuitry  50  may display images on display  14  (e.g., video, still images such as text, alphanumeric labels, photographs, icons, other graphics, etc.) using an array of pixels in display  14 . In self-heating arrangements, control circuitry  50  can use display  14  to display patterns of light (e.g., images or other patterns of light) that heat portion  14 B of display. For example, control circuitry  50  can direct the pixel array in display  14  to illuminate some or all of the pixels in portion  14 B so that heat generated by the illuminated pixels will heat portion  14 B. 
     Control circuitry  50  may be configured to execute instructions for implementing desired control and communications operations in device  10  and systems including multiple devices such as device  10 . For example, control circuitry  50  may be used in processing sensor data, processing user input, processing information received via wireless communications circuitry, and/or other information to determine when to operate device  10  in an independent mode or in a joint operating mode with other devices and to determine which capabilities device  10  and/or other devices should be provided with during these operating modes. 
     Control circuitry  50  may perform these operations using hardware (e.g., dedicated hardware or circuitry) and/or software code (e.g., code that runs on the hardware of device  10  such as control circuitry  50 ). Software code may be stored on non-transitory computer readable storage media (e.g., tangible computer readable storage media). The software code may sometimes be referred to as software, data, program instructions, instructions, or code. The non-transitory computer readable storage media may include non-volatile memory such as non-volatile random-access memory (NVRAM), one or more hard drives (e.g., magnetic drives or solid state drives), one or more removable flash drives or other removable media, other computer readable media, or combinations of these computer readable media or other storage. Software stored on the non-transitory computer readable storage media may be executed on the processing circuitry of control circuitry  50  during operation. 
     In some configurations for device  10 , device  10  may include an electrically adjustable latching mechanism such as latching mechanism  58 . Latching mechanism  58  may be engaged when it is cold and portion  14 B is therefore sensitive to bending stress (e.g., when adhesive or other materials in portion  14 B have become stiff from the cold and susceptible to damage if flexed). By engaging latching mechanism whenever portion  14 B is cold to prevent device  10  from being unfolded, undesired damage to portion  14 B can be avoided. Latching mechanism  58  may be disengaged when the temperature of portion  14 B is sufficiently high to avoid damage during bending. 
     Device  10  may have input-output circuitry  24 . Input-output circuitry  24  may be configured to gather input from users, external devices, and the surrounding environment and may be configured to supply output to users, external devices, and the surrounding environment. As shown in  FIG.  2   , input-output circuitry  24  may include communications circuitry  26  and input-output devices  28 . 
     Communications circuitry  26  may include transceiver circuitry (transmitters and/or receivers) for supporting wired and wireless communications. For example, communications circuitry  26  may support data communications between device  10  and another electronic device over a serial or parallel data path. Device  10  may have communications ports (e.g., Universal Serial Bus ports, etc.) for receiving mating data cables. The data cables can be used to carry data between device  10  and other electronic equipment (e.g., peer devices, etc.). 
     Communications circuitry  26  may include also wireless communications circuitry for communicating wirelessly with external equipment. The wireless communications circuitry 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). 
     Communications circuitry  26  may include radio-frequency transceiver circuitry for handling various radio-frequency communications bands. For example, circuitry  26  may include transceiver circuitry that transmits and receives data in 2.4 GHz and 5 GHz bands for Wi-Fi® (IEEE 802.11) communications and the 2.4 GHz Bluetooth® communications band. Circuitry  26  may include cellular telephone transceiver circuitry for handling wireless communications in frequency ranges such as a low communications band from 700 to 960 MHz, a midband from 1710 to 2170 MHz, and a high band from 2300 to 2700 MHz or other communications bands between 700 MHz and 2700 MHz or other suitable frequencies (as examples). Circuitry  26  may handle voice data and non-voice data. Wireless communications circuitry in circuitry  26  can include circuitry for other short-range and long-range wireless links if desired. For example, circuitry  26  may include millimeter wave communications circuitry (e.g., circuitry for supporting 60 GHz communications and communications in other millimeter wave bands), circuitry for receiving television and radio signals, paging system transceivers, near field communications (NFC) circuitry, etc. Circuitry  26  may also include global positioning system (GPS) receiver equipment for receiving GPS signals at 1575 MHz or for handling other satellite positioning data. In WiFi® 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. 
     Communications circuitry  26  may include one or more antennas. These antennas may be located at one or both ends of device  10 , along the sides of device  10 , at the corners of device  10 , in the middle of the rear face of device  10 , and/or at other locations within housing  12 . Antennas for device  10  may be formed using any suitable antenna types. For example, antennas in circuitry  26  may include antennas with resonating elements that are formed from loop antenna structures, patch 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. Device  10  may include impedance sensors (e.g., impedance measurement circuitry that measures the impedance of antennas and/or other radio-frequency components in circuitry  26 ). These sensors may be used by the control circuitry of device  10  in detecting when external objects are in the vicinity of device  10  (e.g., when part of device  10  is being held in the hand of a user, when part of device  10  such as an edge of device  10  is adjacent to another electronic device, etc.). 
     Devices such as device  10  can be used in isolation or, when brought into the vicinity of additional devices such as device  10  can be used in joint operating modes. An illustrative system in which two electronic devices have been placed adjacent to each other for use in a joint operating mode is shown in  FIG.  3   . As shown in  FIG.  3   , system  36  may include multiple electronic devices such as device  10  of  FIGS.  1  and  2   . System  36  may, as an example, include a pair of devices, two or more devices, three or more devices, four or more devices, five or more devices, 2-4 devices, fewer than five devices, fewer than four devices, or other suitable number of electronic devices  10 . 
     In the example of  FIG.  3   , system  36  includes first electronic device  10 A and second electronic device  10 B. Devices  10 A and  10 B may be peer devices (e.g., devices  10 A and  10 B may both be cellular telephones, may both be wristwatch devices, may both be tablet computers, may both be laptop computers, may both be desktop computers, etc.) or devices  10 A and  10 B may be different types of devices. For example, device  10 A may be a tablet computer and device  10 B may be a cellular telephone, device  10 A may be a laptop computer, and device  10 B may be a tablet computer, device  10 A may be a cellular telephone and device  10 B may be a wrist watch device, etc. In some configurations, devices  10 A and  10 B are of the same general type but have individual differences (e.g., devices  10 A and  10 B may be different cellular telephone models). Configurations for system  36  in which devices  10 A and  10 B have the same size and shape may sometimes be described herein as an example. This is however, merely illustrative. Devices  10 A and  10 B may have different shapes (e.g., outlines when viewed from the front that are circular, oval, triangular, hexagonal, rectangular, etc.) and/or may have different sizes (e.g., device  10 A may have a housing  12  and/or a display  14  that is larger or smaller than the housing and/or display of device  10 B, etc.). 
     As shown in  FIG.  3   , devices  10 A and  10 B may be oriented on a tabletop or other surface so that devices  10 A and  10 B are adjacent (e.g. so that one or more edges of housing  12 A of device  10 A abuts one or more edges of housing  12 B of device  10 B). In the example of  FIG.  3   , the right-hand edge of housing  12 A is aligned with and touching a corresponding left-hand edge of housing  12 B, so that display  14 A of device  10 A and display  14 B of device  10 B can effectively form a single larger display and so that other resources of devices  10 A and  10 B can be used together. Other arrangements in which devices  10 A and devices  10 B are placed adjacent to each other (e.g., so that the housing sidewall along the periphery of one device abuts at least some of the housing sidewall along the periphery of another device) can be used, if desired. 
     Devices  10 A and  10 B may contain components  38  that are located within housings  12 A and  12 B. Components  38  may be located along one or more edge of devices  10 A and  10 B and/or may be located elsewhere within the housings of devices  10 A and  10 B. For example, one or more components  38  may be located along each peripheral edge of devices  10 A and  10 B so that sensing circuitry associated with components  38  can detect external objects around the periphery of each device (e.g. by making sensor measurements through sidewalls of housing  12  or through other portions of housing  12 ). In some configurations, components  38  may make sensor measurements through display  14 . 
     If desired, components  38  may include magnetic components such as permanent magnets, electromagnets, and/or magnetic materials such as iron that are attracted to permanent magnets and electromagnets. These magnetic components help hold devices  10 A and  10 B adjacent to each other. If desired, components  38  and/or the housings of devices  10 A and  10 B may include interlocking male and female parts (e.g., pins and holes, interlocking grooves, or other engagement structures) that help hold devices  10 A and  10 B in desired positions relative to each other. Devices  10 A and  10 B may also be supported by removable sleeves, plastic or leather cases, covers that fold or bend, and/or other supporting structures. 
     Components  38  may include sensors such as sensors  32  of  FIG.  2    for detecting when devices  10 A and  10 B are adjacent to each other. For example, components  38  may include magnetic sensors, force sensors, proximity sensors, antenna impedance sensors, light-based sensors, capacitive sensors, resistive sensors that measure resistance to determine when a metal object such as an electronic device housing is in contact with a given device, switch-based sensors, and/or other sensors that detect when the edge of one device housing abuts at least a portion of an edge of another device housing. Sensors in components  38  may also be configured to operate through the front and rear faces of the housings for devices  10 A and  10 B (e.g., to detect when devices  10 A and  10 B are overlapping in a front-to-front configuration, a back-to-back configuration, or a front-to-back configuration). 
     In general, devices  10  may have any suitable number of components  38  and these components may run along the edges of each device  10  (e.g., on the interior side of a housing sidewall formed from metal, plastic, and/or glass or other materials), and/or may be located at other locations within the interior of the housing for each device  10 ). The configurations of  FIG.  3    are illustrative. 
     Sleeves and other support structures for supporting devices  10 A and  10 B (sometimes referred to herein as covers or cases) may be formed from plastic, metal, fabric, leather or other natural materials, and/or other materials. In some configurations, covers for system  36  may be foldable. 
       FIG.  4    is a cross-sectional side view of system  36  in which devices  10 A and  10 B are supported by a foldable support structure such as cover  38 . Cover  38  of  FIG.  4    has hinge structures  40  that help hold cover  38  in a desired bent shape (e.g., to support device  10 B at an non-zero angle with respect to device  10 A, so that device  10 A can serve as a touch sensitive virtual keyboard while device  10 B serves as a display for presenting a document or other content to a user, etc.). Hinge structures  40  may be formed from interlocking rotatable structures (e.g., a clutch barrel assembly), may include bendable metal or plastic structures (e.g., bendable strip-shaped members that retain their shape when forced into a particular bent or flat position by a user), or other hinge mechanisms. Hinge structures  40  allow a user to place devices  10 A and  10 B in a planar configuration (e.g., lying flat on a table so that devices  10 A and  10 B and their respective displays lie in a common plane) or in a bent configuration of the type shown in  FIG.  4    in which the surface normal of the display of device  10 A is oriented at a non-zero angle with respect to the surface normal of the display of device  10 B and which devices  10 A and  10 B do not lie in a common plane). Attachment structures  42  (e.g., straps, magnets, adhesive, screws or other fasteners, clamps, etc.) may be used in removably attaching devices  10 A and  10 B to cover  38 . 
     As shown in the example of  FIG.  5   , cover  38  may have a foldable portion such as portion  38 F that can be folded into a shape that supports device  10 B at a non-zero angle with respect to device  10 A.  FIG.  6    shows how cover  38  may be folded 180° to allow the front faces of devices  10 A and  10 B to face each other. If desired, covers  38  of  FIGS.  5  and  6    may be provided with hinge structures such as hinge structures  40 . Configurations for cover  38  that support three or more devices  10 , that allow devices  10 A and  10 B to be placed into front-to-back and back-to-back configurations, and/or that allow devices  10 A and  10 B to be supported in other orientations relative to each other may also be used. In some arrangements, device  10 A may be coupled to cover  38  while magnetic components are used in oriented device  10 B relative to device  10 A or magnetic components and cover  38  may be used together in other configurations. For example, cover  38  may form a base to which device  10 A may be attached while magnetic components are used in coupling device  10 B to device  10 A at a desired angle (e.g., a non-zero angle). 
       FIGS.  7 ,  8 ,  9 , and  10    show illustrative configurations in which devices  10 A and  10 B are oriented relative to each other using magnetic components (see, e.g., components  38  along the peripheral edges of devices  10 A and  10 B in  FIG.  3   ). When the edges of the housings of devices  10 A and  10 B are brought together with this type of arrangement, magnetic attraction between magnetic components in respective portions of devices  10 A and  10 B hold devices  10 A and  10 B together. Device housings  12 A and  12 B may have curved sidewalls, flat (vertical) sidewalls, or sidewalls with other suitable cross-sectional profiles. 
     In some configurations, the sidewall profile of devices  10 A and  10 B may help orient devices  10 A and  10 B relative to each other while the respective abutting edges of devices  10 A and  10 B are pulled together by magnetic attraction. As shown in  FIG.  7   , for example, housings  12 A and  12 B may have beveled sidewalls each of which has two beveled 45° sidewall surfaces  44  and one vertical sidewall surface  46 . In the configuration of  FIG.  7   , one of surfaces  46  bears against to one of surfaces  44  (e.g., magnetic attraction from magnetic components in housings  12 A and  12 B couple these surfaces together), so that device  10 B is oriented at 45° relative to device  10 A (e.g., so that device  10 A can serve as a touch sensitive virtual keyboard while device  10 B serves as a display for presenting a document or other content to a user, etc.). In the illustrative configuration of  FIG.  8   , one of vertical sidewall surfaces  46  of device  10 A abuts one of vertical sidewall surfaces  46  of device  10 B, so that devices  10 A and  10 B are held in a planar orientation relative to each other. 
     In the illustrative arrangement of  FIGS.  9  and  10   , device housings  12 A and  12 B have angled (outwardly sloped) sidewall surfaces  48  each of which is oriented at a non-zero angle with respect to surface normal n of displays  14 A and  14 B, respectively. When placed so that sidewall surfaces  48  press against each other and lie in the same plane as shown in  FIG.  9   , device  10 B is supported at a non-zero angle with respect to device  10 A. When placed so that sidewall surfaces  48  are not in direct contact, devices  10 A and  10 B may rest side-by-side in the adjacent device configuration of  FIG.  10    (e.g., so that displays  14 A and  14 B lie in the same plane). 
     Display  14  may cover some or all of the front face of device  10 . If desired, display  14  may have portions that extend over some or all of the sidewalls of housing  12 . As shown in  FIG.  11   , for example, display  14  may have left and right edges that fold down over the left and right sidewalls of each device. When placed adjacent to each other as shown in  FIG.  11   , abutting sidewall portions  14 A′ and  14 B′ of displays  14 A and  14 B, respectively, may be disabled. This allows content (e.g., videos, text, and/or other images) to be displayed in a seamless fashion across the exposed front face surfaces of displays  14 A and  14 B. The outermost portions  14 A′ and  14 B′ of the displays of  FIG.  11    (e.g., portion  14 A′ on the left of device  10 A and portion  14 B′ on the right of device  10 B) may be used to display extended portions of the image displayed on the front faces of devices  10 A and  10 B, may be used to display virtual buttons for system  36 , and/or may be temporarily deactivated. 
     In the arrangement of  FIG.  12   , displays  14 A and  14 B have borderless configurations, so that images can be displayed seamlessly across displays  14 A and  14 B when devices  10 A and  10 B are adjacent (e.g., when the sidewalls of device housings  12 A and  12 B abut). Other configurations for devices  10 A and  10 B may be used, if desired (e.g., configurations in which one or more edges of display  14  has an inactive border). 
       FIG.  13    illustrates how devices  10 A and  10 B may behave when brought together and pulled apart. 
     Initially, devices  10 A and  10 B of system  36  may be in an independent operating mode represented by state  50 - 1 . In state  50 - 1 , devices  10 A and  10 B are separated by an air gap and are not adjacent to each other. Sensors in components  38  can apply measured sensor signals to predetermined adjacency thresholds (adjacency criteria such as a minimum separation distance, sidewall alignment criteria, angular orientation criteria, etc.) to determine whether devices  10 A and  10 B are adjacent or are separated. When separated as shown in state  50 - 1 , each device can operate independently. A single user may operate both devices or each device may be operated by a respective user. 
     Components  38  may monitor whether devices  10 A and  10 B are adjacent. Wireless communications (e.g., handshaking) between devices  10 A and  10 B to determine whether devices  10 A and  10 B are adjacent and/or other techniques for determining adjacency may also be used. In response to detecting that devices are adjacent, system  36  may transition to a joint (adjacent) operating mode, as illustrated by state  50 - 2  of  FIG.  13   . 
     In state  50 - 2 , some or all of the functions of devices  10 A and  10 B may continue to operate independently. For example, devices  10 A and  10 B may display separate content on their respective displays (e.g. a first web page on device  10 A and a second web page on device  10 B) and/or may play separate audio. At the same time, the joint operating mode may allow at least some of the functions of devices  10 A and  10 B to be shared. As an example, a wireless communications circuit in device  10 A may transmit and receive data for both device  10 A and device  10 B (and this data may be exchanged locally between devices  10 A and  10 B using a wired or wireless link between devices  10 A and  10 B) or measurements from an ambient light sensor in device  10 A may be used in controlling screen brightness in the displays of both devices  10 A and  10 B. 
     If desired, devices  10 A and  10 B may operate in a coordinated fashion during the joint mode of state  50 - 2  so that most or all functions of the devices are coordinated. For example, images that are displayed may be expanded to stretch across displays  14 A and  14 B to provide a user with an expanded display area, stereo audio may be played from a first speaker in device  10 A and a second speaker in device  10 B, touch input may be gathered from displays  14 A and  14 B so that a user can drag on-screen items from display  14 A to display  14 B or can make touch gestures that extend across displays  14 A and  14 B, wireless communications capabilities of devices  10 A and  10 B may be combined to provide enhanced bandwidth and/or additional bands of coverage, etc. 
     In some arrangements, devices  10 A and  10 B may be operated in a master-slave (mother/child) configuration. In this type of arrangement, the operation of one device is used in controlling the operation of another device. As an example, device  10 A may display a virtual keyboard for system  36  and device  10 B may display documents or other content that is being controlled by input supplied to the keyboard. Device  10 A may also serve as video controller device, a color picker input area, brush selection area, or other input area for an image editing application that is displaying an edited image on device  10 A, may serve as a game controller pad or video playback controller pad with stop, pause, forward, and reverse button for device  10 B, or may otherwise serve as a touch controller for device  10 B. 
     Operations in each of these modes need not be mutually exclusive. For example, devices  10 A and  10 B may initially be operated independently in all respects (state  50 - 1 ). In joint mode (state  50 - 2 ), a first device function (e.g., use of wireless communications circuitry  26  to receive email messages) may remain separate on each device, a second device function (e.g., audio playback) may be shared (e.g., by presenting the audio in a synchronized stereo arrangement in which a speaker in device  10 A provide left channel audio for an audio track while a speaker in device  10 B simultaneously provides right channel audio for the same track), and a third device function (e.g., use of displays  14 A and  14 B) may be implemented using a master-slave arrangement (e.g., device  10 A may use display  14 A as a touch keyboard and device  10 B may use display  14 B as a display to present an edited image or other content to a user). 
     With the illustrative configuration of  FIG.  13   , devices  10 A and  10 B initially present separate content (respectively, content A and content B) to their respective users (or to a single user of both devices). When placed adjacent to each other so that system  36  operates in joint state  50 - 2 , content A is presented using both displays  14 A and  14 B, whereas content B is no longer presented. Content A may be, for example, a video whereas content B may be a desktop screen containing an array of selectable icons. A user may be playing the video on device  10 A when device  10 B is brought into contact with device  10 A. When this configuration is detected, devices  10 A and  10 B can operate together to display a first half of content A on device  10 A and a second half of content A on device  10 B. In this way, the user may benefit from an enlarged display area and expanded stereo sound (by using respective speakers in devices  10 A and  10 B to present stereo to the user). 
     During joint operating mode (state  50 - 2 ), devices  10 A and/or  10 B may use components  38  (e.g., sensors  32 ) and optional handshaking procedures (e.g., messages relayed between devices  10 A and  10 B wirelessly upon detection of adjacency using sensors  32 ) to determine whether devices  10 A and  10 B are adjacent. In response to detecting that devices  10 A and  10 B are no longer adjacent, devices  10 A and  10 B may transition to an updated operating mode such as a mode corresponding to one of operating states  50 - 3 ,  50 - 4 , and  50 - 5  of  FIG.  13   . The behavior of devices  10 A and  10 B after devices  10 A and  10 B are separated (e.g., whether system  36  transitions to state  50 - 3 ,  50 - 4 , or  50 - 5 ) can depend on the configuration of devices  10 A and  10 B during operating state  36  and/or other criteria. 
     Consider, as an example, a first scenario in which devices  10 A and  10 B are displaying a video that stretches across displays  14 A and  14 B in state  50 - 2 . The video (content A in this example) originated from device  10 A (via streaming or a video stored in storage in the control circuitry of device  10 A). When devices  10 A and  10 B are separated, system  36  transitions to the operating mode of state  50 - 3 . In state  50 - 3 , device  10 A continues to display the same video with its audio track, so that the user&#39;s viewing of the video is not disrupted. Device  10 B reverts to its original operating mode and displays content B (which may be, for example, a list of selectable icons on a desktop, an email inbox, or other functionality that is potentially specific to device  10 B). 
     In a second illustrative scenario, devices  10 A and  10 B transition from state  50 - 2  to state  50 - 4  when separated. In state  50 - 2 , content for a video is spread across displays  14 A and  14 B. In this example, the content is being watched by two users who decided to share their screens during the joint operating mode of state  50 - 2 . When the two users need to separate their devices  10 A and  10 B (e.g., for more convenient viewing angles, because the users are departing for different destinations, etc.), both users desire to continue viewing the video. Accordingly, in this second operating scenario, the video (content A) is displayed separately (in its entirety) on each of displays  14 A and  14 B. If the video was initially stored locally on only one of the devices, the video can be transferred to the other device during state  50 - 2  (e.g., using a local communications link between devices  10 A and  10 B) or that other device can retain access to the video by automatically switching to an on-line video streaming delivery mode when the devices are separated. In scenarios in which the shared content on system  36  of state  50 - 2  is a website, the website can be displayed separately on both display  14 A and  14 B in state  50 - 4 . 
     In a third illustrative scenario, devices  10 A and  10 B transition from state  50 - 2  to state  50 - 5  when separated. The content displayed on displays  14 A and  14 B of system  36  in state  50 - 2  may correspond to a game with two users. In the combined display arrangement of state  50 - 2 , a first user&#39;s portion of the game (e.g., the first user&#39;s game controller and/or a first portion of a game playing space) is displayed on display  14 A, whereas a second user&#39;s portion of the game (e.g., the second user&#39;s game controller and/or a second portion of the game playing space) is displayed on display  14 B. Upon transitioning to state  50 - 5 , the first user&#39;s game controller and/or the first portion of a game playing space may continue to be displayed on display  14 A, whereas the second user&#39;s game controller and/or the second portion of the game playing space is displayed on display  14 B. This allows the two users to continue to play a shared game (perhaps in a mode in which it is desirable for each user&#39;s input to their game controller to not be revealed to the opposing user). At a later stage of game play, the users may recombine their devices to revert to state  50 - 2 . Local wireless communications links or communications links that pass through the internet may be used to allow the first and second user&#39;s to play the shared game in state  50 - 5 . 
     In some joint operating modes, devices  10 A and  10 B may be oriented so that they overlap each other in a front-to-front configuration in which their displays overlap and face each other (see, e.g., the arrangement of  FIG.  14   ), in a back-to-back configuration in which their displays overlap and face away from each other so that their rear faces are facing each other (see, e.g., the arrangement of  FIG.  15   ), or in a front-to-back configuration in which their displays are facing in the same direction (see, e.g.,  FIG.  16   ). The orientation of devices  10 A and  10 B in these scenarios can be detected by components  38  and operation of devices  10 A and  10 B adjusted accordingly. When, for example, devices  10 A and  10 B are in a front-to-front configuration, displays  14 A and  14 B may be powered down to conserve power. When devices  10 A and  10 B are in a back-to-back configuration, one or both of displays  14 A and  14 B may be active. For example, a display facing up may be on and a display facing down may be turned off. The orientation of devices  10 A and  10 B relative to the Earth may be detected using an accelerometer in device  10 A and/or device  10 B. In a back-to-front configuration, it may be desirable to turn on the exposed display while turning of the covered (downward facing) display. In each of these joint operation modes, devices resources such as audio resources, communications circuitry, sensors, and other input-output circuitry  24  can be shared, if desired. Magnetic components (see, e.g., components  38 ) may be used in coupling devices  10 A and  10 B together in overlapping configurations. 
     Illustrative operations involved in using multiple devices  10  (e.g., devices  10 A and  10 B) are shown in  FIG.  17   . During the operations of block  60 , devices  10 A and devices  10 B may be operated in an independent operating mode (see, e.g., state  50 - 1  of  FIG.  13   ). During this mode, device  10 A and/or device  10 B may use components  38  (e.g., sensors  32 ) to monitor for adjacency between devices  10 A and  10 B. If desired, output from components  38  in device  10 A and/or device  10 B may be used to initially detect that a sidewall along an edge of device  10 B is adjacent to one of the sidewalls along an edge of device  10 A and this initial detection may be confirmed using wireless communications between devices  10 A and  10 B (sometimes referred to as handshaking, authentication, or acknowledgement). For example, if device  10 A detects the presence of a possible adjacent device, device  10 A can issue a near-field communications request or other wireless request asking adjacent devices to identify themselves. In response, device  10 B can use its sensor(s)  32  to confirm adjacency and can wirelessly provide device  10 A with this information and/or information on the identity of device  10 B and/or other information confirming that device  10 B is authorized and desires to jointly operate with device  10 A. Configurations in which devices  10 A and/or  10 B generate confirmatory patterns of magnetic fields (e.g., a magnetic field produced by device  10 B that is detected by a magnetic sensor in device  10 A), acoustic signals or vibrations (e.g., a sound or vibration that is generated by device  10 B and detected by a microphone or accelerometer in device  10 A), light (e.g., light from a light-emitting diode in device  10 B that is detected by a light detector in device  10 A), and/or other in which devices  10 A and  10 B otherwise generate unidirectional and/or bidirectional localized confirmatory information may also be used in determining adjacency. Simultaneous accelerometer signatures (e.g., simultaneous bumps that are detected by the accelerometers in each device when the devices first contact each other) may also be used as part of an adjacency detection scheme. In general, adjacency between devices  10 A and  10 B can be determined by using data from adjacency detection sensors, receipt of wireless communications from an adjacent device, and/or other operations that take place in one of devices  10 A and  10 B or that take place in both devices  10 A and  10 B. Configurations in which adjacency status information (e.g., sensor readings indicative of device adjacency) is shared between devices  10 A and  10 B (e.g., when adjacency is confirmed when device  10 A detects the presence of device  10 B with a sensor in device  10 A and when device  10 B detects the presence of device  10 A with a sensor in device  10 B) may enhance adjacency detection reliability. In response to determining that devices  10 A and  10 B are not adjacent (from information gathered using one or more of sensors  32  and/or other detection mechanisms), monitoring may continue at block  60 , as indicated by line  62 . 
     In response to determining that devices  10 A and  10 B are adjacent (e.g., in response to detection of adjacency by the control circuitry and sensors of either device  10 A or device  10 B or both and/or confirmation using other adjacency detection/confirmation mechanisms), devices  10 A and  10 B may transition to a joint operating mode (block  64 ). The transition to joint operation may take place automatically or may proceed in response to user confirmation by the user of device  10 A and/or the user of device  10 B that joint operation is desired and authorized. As an example devices  10 A and  10 B may display an on-screen interactive prompt asking each user (e.g., if there are two users) to enter a password and to confirm that joint operation is desired. Devices  10 A and  10 B may then proceed to operate in a joint operating mode, as described in connection with state  50 - 2  of  FIG.  13   . 
     In the joint operating mode, one or more resources in device  10 A may be shared with one or more corresponding resources in device  10 B. As an example, graphics circuitry in the control circuitry of each device may be shared so that images can be displayed across a combined display formed from each of the adjacent displays. During image presentation operations, the graphics circuitry (e.g., a graphics processing unit) in one device may, as an example, render content for both displays and may transfer this content to respective display driver circuitry in each device for displaying on the display of that device. A local wireless link between devices  10 A and  10 B can be used to transfer content to be displayed from device  10 A to device  10 B (as an example) or, in some configurations, devices  10 A and  10 B may independently gather their portions of the content to be displayed from an on-line source or other remote source. Local rendering operations performed based on shared information (e.g., when each part of the shared content corresponds to a user&#39;s game controller and/or game playing space) may also be used. In some embodiments, content to be displayed across both displays may be divided before graphics rendering operations and a graphics processing unit in each device may handle rendering operations for its portion of the split content. Each device may have its own display driver circuitry coupled to a pixel array in its own display. The display driver circuitry of each device may be used in displaying an appropriate portion of the content for that device on its display. 
     As further examples, first and second microphones in devices  10 A and  10 B may be used jointly to capture stereo audio input, first and second cameras in devices  10 A and  10 B respectively may be used to capture stereo (e.g., three dimensional) images, first and second respective cameras may be used to gather user free-space gestures (e.g. using triangulation to gather three-dimensional gesture input), or first and second respective cameras may be used to capture image recognition images of a user&#39;s face from first and second respective perspectives. Touch screen functionality may be merged across displays  14 A and  14 B (e.g., to allow icons and other items to be dragged from one display to another, to allow a user touch gesture to extend across multiple displays, to allow a stylus, finger, or other input device to draw a line that extends across multiple displays, etc.). Wireless circuitry in devices  10 A and  10 B may be used jointly (e.g., to double downloading and uploading bandwidth by combining data streams from the two devices), wired circuitry in devices  10 A and  10 B may be used jointly (e.g., to allow multiple accessories to be coupled to system  36 —one of which is coupled to a port in device  10 A and another of which is coupled to a port in device  10 B), and other communications and control functions can be operated jointly. 
     If desired, sensors such as ambient light sensors and proximity sensors may be used jointly. For example, if an ambient light sensor in device  10 A is shadowed by a user&#39;s hand, readings from an ambient light sensor in device  10 B may be used in adjusting the screen brightness for the combined display formed from displays  14 A and  14 B. Proximity sensor measurements may be gathered from respective proximity sensors in devices  10 A and  10 B (e.g., to determine whether a user is placing the user&#39;s ear next to an ear speaker in either device  10 A or device  10 B). 
     To conserve power, some circuitry may be disabled in one device while the circuitry of the other device is used for both devices  10 A and  10 B. For example, when devices  10 A and  10 B are used jointly, global positioning system circuitry in one device may be disabled to conserve power while global positioning system circuitry in the other device is enabled to gather satellite navigation system readings. 
     Displays  14 A and  14 B may, if desired, use common brightness and color balance (white point) settings so that content appears uniform across displays  14 A and  14 B. Devices  10 A and  10 B can revert to their original settings when separated or can (at least temporarily) retain shared joint operating mode settings. 
     Components  38  (e.g., sensors  32 ) in devices  10 A and/or  10 B can monitor for device adjacency during the joint operations of block  64 . For example, one or both devices may make sensor measurements to detect when devices  10 A and  10 B are pulled apart and/or wireless communications between devices  10 A and  10 B may be used in determining when devices  10 A and  10 B are no longer adjacent. So long as devices  10 A and  10 B are positioned so that devices  10 A and  10 B are adjacent (e.g., so that the edges of devices  10 A and  10 B abut one another in a side-by-side or overlapping arrangement) and a wired or wireless communications link is supported between devices  10 A and  10 B so that the control circuitry of devices  10 A and  10 B can share information and otherwise operate cooperatively to support joint operation, processing may continue at block  64 , as indicated by line  66 . In response to detecting that devices  10 A and  10 B have been separated, system  36  may transition from a joint operating mode (e.g., state  50 - 2  of  FIG.  13   ) to an appropriate separate (independent) operating mode (see, e.g., states  50 - 3 ,  50 - 4 , and  50 - 5  of  FIG.  13   ). During the operations of block  68 , it may be determined which, if any, of the operating settings from the joint state are to persist on each of the separate devices before operation loops back to the independent operations of block  60 . As an example, if devices  10 A and  10 B were jointly displaying a web page during the operations of block  64 , the web page may continue to be displayed on each device after device separation (e.g. each device may display a browser window with the same web page). As another example, if devices  10 A and  10 B were playing stereo music through respective first and second speakers in devices  10 A and  10 B, device  10 A (but not device  10 B) may continue to play the music through its speakers upon device separation. In general, all joint operating parameters may be retained when devices  10 A and  10 B are separated, some joint operating parameters may be retained, or no joint operating parameters may be retained. 
     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. 
     An illustrative electronic device of the type that may be provided with a flexible display is shown in  FIG.  18   . 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 wrist-watch device, a pendant device, a wearable or miniature device of other types, a computer display that does not contain an embedded computer, a computer display that includes 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.  18   , device  10  is a portable device such as a cellular telephone, media player, tablet computer, watch or other wrist device, or other portable computing device. Other configurations may be used for device  10  if desired. The example of  FIG.  18    is merely illustrative. 
     In the example of  FIG.  18   , device  10  includes a display such as display  14  mounted in 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 hinge structures such as hinge  20  to allow device  10  to bend about bend axis  22 . Housing  12  may have first and second housing portions that rotate with respect to each other as device  10  is bent (folded) about bend axis  22  using hinge  20  or other flexible structures joining the first and second housing portions. 
     Display  14  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. A touch sensor may be formed using electrodes or other structures on a display layer that contains a pixel array or on a separate touch panel layer that is attached to the pixel array (e.g., using adhesive). In various embodiments, the on-cell touch sensors can be directly fabricated on top of OLED display panel. 
     Display  14  may include pixels formed from liquid crystal display (LCD) components, electrophoretic pixels, microelectromechanical (MEMs) shutter pixels, electrowetting pixels, micro-light-emitting diodes (small crystalline semiconductor die), organic light-emitting diodes (e.g., pixels in a thin-film organic light-emitting diode display), or pixels based on other display technologies. Configurations in which display  14  has an array of light-emitting pixels such as an array of organic light-emitting diode pixels may sometimes be described herein as an example. 
     Display  14  may have a portion that overlaps bend axis  22 . To facilitate bending of device  10  about axis  22 , all of display  14  may be formed using flexible structures or at least the portion of display  10  that overlaps bend axis  22  may be formed using flexible structures. A display cover layer or other layer may form the outermost surface of the display. Display layers such these (e.g., display cover layers) may be formed from glass, plastic, and/or other transparent display cover layer structures and may be flexible (at least where these layers overlap bend axis  22  of device  10 ). 
     As shown in  FIG.  18   , for example, display  14  may have three portions such as portions  14 A,  14 B, and  14 C. In portions  14 A and  14 C, display  14  may be flexible or may be rigid (e.g., the pixel array in these areas may be rigid and/or the display cover layer structures in these regions may be rigid). Flexible portion  14 B overlaps bend axis  22  and forms a strip that lies between portions  14 A and  14 C and that extends across the width of the display between opposing edges of the display. To ensure that flexible portion  14 B is sufficiently flexible to allow device  10  to bend about axis  22 , display layers such as a display cover layer for display  14  may be formed from a thin flexible glass or polymer layer that accommodates bending of display  14  about axis  22  and underlying display layers (e.g., a polymer substrate, metal traces, a polarizer layer, a touch sensor layer, adhesive layers, and other conducting and dielectric layers in an organic light-emitting diode pixel array) may also be formed from flexible materials and structures. 
     In cold operating environments (e.g., temperatures significantly below room temperature such as temperatures below 10° C., below 0° C., −40° C. to −10° C., or other cold temperatures), materials such as adhesives in flexible portion  14 B may become inflexible. To help avoid damage to flexible portion  14 B when device  10  is bent open or closed about axis  22 , flexible portion  14 B may be heated (e.g., while other portions such as portions  14 A and  14 C of display  14  are not heated or are heated less to conserve energy). Portion  14 B may, for example, be heated by using heat spreading structures that help spread heat from integrated circuits and other components in device  10  to portion  14 B. With another illustrative arrangement, a heating element under portion  14 B may be used to heat portion  14 B. Another illustrative arrangement involves self-heating operations. In a self-heating arrangement, pixels in display  14  are illuminated. For example, the light-emitting diodes in at least those pixels in display  14  that are in portion  14 B may be turned on to produce light and heat. The heat produced by the illuminated pixels can heat portion  14 B (e.g., to room temperature or other suitable temperature that is elevated relative to an initial cold temperature) and help prevent damage to sensitive structures in portion  14 B as portion  14 B is bent about axis  22 . In various embodiments, the heating area may be larger than portion  14 B because the adhesive can be a continuous film under  14 A and  14 C and can stretch and shear during bending/unbending of the display. 
     As shown in  FIG.  19   , device  10  may be folded (bent by 180° or other suitable amount) about bend axis  22  so that display  14  is visible from the outside of device  10  in its folded state.  FIG.  20    shows how device  10  may be folded about bend axis  22  so that display  14  is protected within the interior of device  10 . Device  10  may have flexible structures (e.g., a hinge) to allow outward bending of the type shown in  FIG.  19   , to allow inward bending of the type shown in  FIG.  20   , or to allow bending of both the type shown in  FIG.  19    and the type shown in  FIG.  20   . Configurations in which device  10  is flexed by different amounts (e.g., more than 180° or less than 180°) may also be used. 
     Display  14  may have a rectangular shape (i.e., display  14  may have a rectangular footprint and a rectangular peripheral edge that runs around the rectangular footprint) or may have other suitable shapes. A top view of circuitry in an illustrative display with a rectangular shape is shown in  FIG.  21   . As shown in  FIG.  21   , display  14  may have an array of pixels  42  formed on substrate  36 . Substrate  36  may be formed from glass, metal, plastic, ceramic, or other substrate materials. Pixels  42  may receive data signals over signal paths such as data lines D and may receive one or more control signals over control signal paths such as horizontal control lines G (sometimes referred to as gate lines, scan lines, emission control lines, etc.). There may be any suitable number of rows and columns of pixels  42  in display  14  (e.g., tens or more, hundreds or more, or thousands or more). Each pixel  42  may have a light-emitting diode  26  that emits light  44  under the control of a pixel circuit formed from thin-film transistor circuitry such as thin-film transistors  28  and thin-film capacitors). Thin-film transistors  28  may be polysilicon thin-film transistors, semiconducting-oxide thin-film transistors such as indium gallium zinc oxide transistors, or thin-film transistors formed from other semiconductors. Pixels  42  may contain light-emitting diodes of different colors (e.g., red, green, and blue diodes for red, green, and blue pixels, respectively) to provide display  14  with the ability to display color images. 
     Display driver circuitry may be used to control the operation of pixels  42 . The display driver circuitry may be formed from integrated circuits, thin-film transistor circuits, or other suitable circuitry. Display driver circuitry  30  of  FIG.  21    may contain communications circuitry for communicating with system control circuitry such as control circuitry  50  of  FIG.  2    over path  32 . Path  32  may be formed from traces on a flexible printed circuit or other cable. During operation, the control circuitry (e.g., control circuitry  50  of  FIG.  2   ) may supply circuitry  30  with information on images to be displayed on display  14 . 
     To display the images on pixels  42 , display driver circuitry  30  may supply image data to data lines D while issuing clock signals and other control signals to supporting display driver circuitry such as gate driver circuitry  34  over path  38 . If desired, circuitry  30  may also supply clock signals and other control signals to gate driver circuitry on an opposing edge of display  14  or may use display driver circuitry with other layouts. The configuration of  FIG.  21    is illustrative. 
     Gate driver circuitry  34  (sometimes referred to as horizontal control line control circuitry) may be implemented as part of an integrated circuit and/or may be implemented using thin-film transistor circuitry. Gate lines G (sometimes referred to as horizontal control lines) in display  14  may carry gate line signals (sometimes referred to as scan line signals, emission enable control signals, etc.) for controlling the pixels of each row. There may be any suitable number of control signals per row of pixels  42  (e.g., one or more, two or more, three or more, four or more, etc.). 
     Some or all of pixels  42  in the pixel array of display  14  can be illuminated (fully or partially). Turning pixels  42  on in this way creates a pattern of light on display  14 . The pattern of light may include text, icons, a logo or other images, may be a solid or graded block, or may form any other image or abstract pattern (e.g., a solid bright white area, an area of a particular color or pattern of colors, a photograph, etc.). To conserve energy, it may be desirable to only or to primarily illuminate pixels  42  that overlap flexible portion  14 B of display  14 , as shown in  FIG.  22   . With this type of arrangement, the pixels in region  14 B may be configured to output light  44  at their maximum intensity. 
       FIGS.  23  and  24    show how device  10  may have a latching mechanism that is used to hold housing  12  and device  10  in a closed (folded) configuration when portion  14 B of display  14  is cold. In the example of  FIG.  23   , housing  12  has been bent about bend axis  22 , so that end portion (housing structures)  12 A and end portion (housing structures)  12 B of housing  12  face each other. In this example, display  14  has been folded inwardly. Outwardly folding display arrangements may also be used, if desired. 
     When housing  12  is folded so that portions  12 A and  12 B are adjacent to each other, the latching mechanism can be engaged (e.g., to prevent damage to display  14  while portion  14 B is cold). When it is desired to release portions  12 A and  12 B and thereby allow device  10  to be opened for use, the latching mechanism can be disengaged. 
     The illustrative latching mechanism of  FIG.  23    includes first component  70  in device housing portion  12 A and second component  72  in device housing portion  12 B. Components  70  and  72  may interact magnetically when it is desired to hold device  10  in a folded (closed) state. In one illustrative configuration, both of components  70  and  72  are electromagnets. In another illustrative configuration, component  72  may be an electromagnet and component  70  may be a magnetic structure (e.g., a permanent magnet or a magnetic structure formed from iron, ferrite, or other magnetic material). When control circuitry  50  activates the electromagnet(s), housing portion  12 A and housing portion  12 B are held together by magnetic attraction and the user of device  10  will be prevented from unfolding device  10 . When it is desired to disengage the magnetic latching mechanism of  FIG.  23   , control circuitry  50  can turn off the control signals (drive current) applied to the electromagnet(s). 
     The illustrative latching mechanism of  FIG.  24    includes electrically controlled actuator  74  and latch member  76  in housing portion  12 B and a corresponding latch member such as pin  78  in housing portion  12 B. When latch member  76  is placed in the position shown in  FIG.  11   , latch member  76  will engage pin  78  and thereby hold portions  12 A and  12 B to each other. When control circuitry  50  uses actuator  74  to move latch member  76  in direction  79 , latch member  76  will disengage from pin  78 , thereby releasing portions  12 A and  12 B so that device  10  can be unfolded by moving these portions away from each other. 
       FIG.  25    illustrates an exemplary depiction of the protective features of the exemplary foldable device. In a first position  1502 , the foldable device  10  is dropped from a height  2506  above the ground. In the first position  1502  the display is unfolded or flat. The device  10  can include edges  2504  around the display  14 . The edges  2504  can be reinforced to be able to withstand forces. 
     A sensor in the device  10  senses the acceleration of the device. If the acceleration of the device  10  exceeds a predetermined threshold, protective features are engaged to protect the display  14 . For example, if the device  10  is dropped from a height  2506 , the sensor in the device  10  can detect the acceleration or motion and after a threshold limit is reached the protective features of the device  10  can be engaged. The protective features can include folding the display  14  about the hinge so the angle between either the two displays or two portions of the same display  14  are at an angle  2508  less than 180 degrees. In this way, in a second position  2510  the device  10  can strike the ground so that the display  14  is protected. The device  10  can strike on the edges  2504  instead of the display  14 , in order for the edges  14  to absorb the forces from the drop. 
       FIG.  26 A  illustrates a first exemplary depiction of the protective features of the exemplary foldable device.  FIG.  26 A  illustrates a device  10  with a foldable display  14 . The display can include a motorized hinge  2602  as a release mechanism. The motorized hinge  2602  can include a reverse rotation (e.g., closing) of a motor when a fall is detected. In various embodiments the motorized hinge  2602  can close the display to an angle less than 180 degrees. In various embodiments, the motorized hinge  2602  can close the display  14  completely, depending on the speed of the motor and the height the device  10  is dropped from. 
       FIG.  26 B  illustrates a second exemplary depiction of the protective features of the exemplary foldable device.  FIG.  26 B  illustrates a device  10  with a foldable display  14 . The display can include a detent  2612  (e.g., a spring-loaded detent) as a release mechanism. The detent  2612  can work with a mechanical hinge  2614 . The detect can be electro-mechanically released with spring force from the hinge. After the spring-loaded detent is retracted a spring force on the hinge can mechanically cause the device to close, at least partially if the acceleration exceeds a predetermined threshold. The detent can be released when a fall is detected. In various embodiments the detent  2612  can close the display to an angle less than 180 degrees. In various embodiments, the detent  2612  can close the display  14  completely, depending on height the device  10  above the ground. 
     The device  10  can collects sensor data regarding the motion of the user. For instance, using the motion sensors (e.g., one or more accelerometers), the device  10  can measure an acceleration experienced by the motion sensors, and correspondingly, the acceleration experienced by the device  10 . Further, using the motion sensors (e.g., one or more compasses or gyroscopes), the device  10  can measure an orientation of the motion sensors, and correspondingly, an orientation of the device  10 . In some cases, the motion sensors can collect data continuously or periodically over a period of time or in response to a trigger event. In some cases, the motion sensors can collect motion data with respect to one or more specific directions relative to the orientation of the device  10 . For example, the motion sensors can collect sensor data regarding an acceleration of the device  10  with respect to the x-axis (e.g., a vector projecting from a side edge of the device  10 , the y-axis (e.g., a vector projecting from a front edge of the  10 , and/or the z-axis (e.g., a vector projecting from a top surface or screen of the mobile device  10 , where the x-axis, y-axis, and z-axis refer to a Cartesian coordinate system in a frame of reference fixed to the device  10  (e.g., a “body” frame). 
     As the user moves, the device  10  can use the motion sensors to continuously or periodically collect sensor data regarding an acceleration experienced by the motion sensors with respect to y-axis over a period of time. The resulting sensor data can be presented in the form of a time-varying acceleration signal. In some cases, the acceleration system can obtain acceleration samples at a sample frequency of 800 Hz using the motion sensors, with a sampling bandwidth of 200 Hz. In practice, other sampling frequencies and/or sampling bandwidths are also possible. 
     In the example above, the acceleration signal indicates the acceleration experienced by the device  10  with respect to the y-axis of the device. In some cases, the acceleration signal can also indicate the acceleration experienced by the device  10  with respect to multiple different directions. For example, the acceleration signal can include an x-component, a y-component, and a z-component, referring to the acceleration experienced by the device  10  with respect to the x-axis, the y-axis, and the z-axis of the device  10 , respectively. Each component also can be referred as a channel of the acceleration signal (e.g., “x-channel,” the “y-channel,” and the “z-channel”). 
     The device  10  can analyze the acceleration signal to determine whether the device  10  has fallen. For instance, if the device  10  has fallen, the device  10  may experience a relatively strong impact (e.g., when the device  10  strikes the ground). Such an impact can be identified based on a magnitude of the acceleration experienced by the device  10  (e.g., the rate of change in the velocity of the mobile device), a magnitude of the jerk experienced by the mobile device (e.g., the rate of change in the acceleration of the mobile device), and an oscillatory behavior of the acceleration experienced by the device  10 . Each of these parameters can be determined using the acceleration signal. 
     As an example, the magnitude of the acceleration experienced by the device  10  can be determined, for each channel of the acceleration signal, using the relationship:
 
mag=max(abs( a ( n ))),
 
where mag is the magnitude of acceleration for that channel, a(n) is the nth sample of the acceleration signal for that channel, and max is the maximum calculated over a sliding window of samples of the acceleration signal, nwindow. In some cases, nwindow can correspond to the number of samples spanning an interval of time of 0.2 seconds or approximately 0.2 second. For example, if the sampling frequency for the acceleration signal is 800 Hz, nwindow can be 160. In practice, other values for nwindow are also possible.
 
     Alternatively, the magnitude of the acceleration experienced by the device  10  can be determined, for each channel of the acceleration signal, using the relationship:
 
mag=max( a ( n ))−min( a ( n )),
 
where mag is the magnitude of acceleration for that channel, a(n) is the nth sample of the acceleration signal for that channel, max is the maximum calculated over a sliding window of samples nwindow, and min is the minimum calculated over the window of samples the acceleration signal, nwindow. As above, in some cases, nwindow can correspond to the number of samples spanning an interval of time of 0.2 seconds or approximately 0.2 second, though in practice, other values for nwindow are also possible.
 
     If the acceleration signal includes acceleration measurements with respect to a single direction (e.g., having a single channel, such as a y-channel), the magnitude of the acceleration with respect to that direction can be determined using the relationship above. The resulting value is representative of the magnitude of the acceleration for the acceleration signal. Alternatively, the total energy from all three channels over the window of interest (e.g. nwindow) may be used as the total magnitude of acceleration. For example, one notion of total energy could be computed as:
 
mag=√max(| x |) 2 +max(| y |) 2 +max(| z |) 2 )
 
     If the acceleration signal includes acceleration measurements with respect to multiple directions (e.g., having multiple channels, such as a x-channel, a y-channel, and a z-channel), the magnitude of the acceleration with respect to each direction can be individually determined using the relationship above, resulting in three individual magnitude values (corresponding to the three channels, respectively). The greatest magnitude value can be selected as representative of the magnitude of the acceleration for the acceleration signal. In various embodiments, the threshold vertical acceleration (e.g., z-channel) can be the acceleration forces due to gravity (e.g., 9.8 meters per second per second). In various embodiments, the features will only be triggered in free-fall acceleration or vertical acceleration (i.e., if the device is thrown) to avoid triggering the features when users are riding in a car, a train, or an airplane etc. In various embodiments, the features can be selectively enabled and disabled (e.g., riding a roller coaster while taking a selfie.) 
       FIG.  27    is a diagram of a device  200  having one or more electronic flexible screen or display devices  2702 . The one or more electronic flexible screen or display devices  2702  may be configured, manufactured, produced, or assembled based on the descriptions provided in U.S. Patent Publication Nos. 2007-247422, 2007-139391, 2007-085838, or 2006-096392 or U.S. Pat. No. 7,050,835 or WO Publication No. 2007-012899 all herein incorporated by reference as if fully set forth. The one or more electronic flexible screen or display devices  2702  may be configured and assembled using organic light emitting diodes (OLED), liquid crystal displays using flexible substrate technology, flexible transistors, field emission displays (FED) using flexible substrate technology, as desired. In the case for multiple electronic flexible screens or display devices  2702 , rotation  2714  reveals a second electronic flexible screen or display device  2703  on the back of device  2700 . 
     Any one of housing members  2704  and  2706  selectively house certain hardware components described in device  2700  such as one or more processors, memory, one or more sensors, and one or more network adapters. In one embodiment of the invention, housing members  2704  and  2706  may each have individual transmitting/receiving antennas  2716  and  2718  for providing spatial and time diversity. One or more electronic flexible screen or display devices  2702  can optionally be configured to collapse  2708  and roll up into housing members  2704  or  2706  for portability. For orientating device  2700  in a circular manner for a presentation or posting on a light post as an advertisement, attachment members  2710  and  2712  may be used. Housing members  2704  and  2706  may be rectangular or cylindrical and provide grasping positions, the ability to position device  2700  upright on a flat surface, or the ability to mount device  2700  on a flat surface, as desired. It is appreciated by one skilled in the art that housing members  2704  and  2706  and one or more electronic flexible screen or display devices  2702  are not drawn to scale. They may have different shapes and dimensions while configured to provide the same functionality provided herewith. 
     Still referring to  FIG.  27   , in another embodiment device  2700  may optionally have a liquid crystal display (LCD), LED, FED, or OLED display unit  2720 . For this case, when one or more electronic flexible screen or display devices  2072  is collapsed into housing member  2706  adjacent display unit  2720  is still available for displaying content. When one or more electronic flexible screen or display devices  2702  is expanded out of housing member  2704  or  2706 , the combination of display unit  2720  and flexible screen or display devices  2702  provides a larger screen size for a single graphical feed or for having separate graphical feeds or windows in each display unit, as desired. In this configuration, the images displayed on flexible screen or display devices  2702  can be responsive to one or more sensors detecting a bending of flexible screen or display devices  2702 . 
       FIG.  28    is schematic cross-sectional side view illustration of a system  2800  including a flexible display panel  2802  secured to a spool  2810  in accordance with an embodiment of the invention.  FIG.  28    is a schematic cross-sectional side view illustration of a flexible display panel  2802  including an array of LEDs and microchips in a display area on a front surface of the display substrate in accordance with an embodiment of the invention. In various embodiments, the display panel  2802  can also include an OLED display. The display panel  2802  may be similar to any of the display panels previously described above. In the embodiment illustrated in  FIG.  28   , the flexible display panel  2802  is rollable into and out of a housing  2820 . In such an embodiment, rather than locating the driver ICs  2830  additional IC chips  2834  and battery  2838  on the back surface of the display substrate, any combination of these components can be located within the housing  2820 , such as on the spool  2810 . In other embodiments, any of these components may also be located on the back surface of the display substrate. For example, a thin film battery  2838  can be located on the back surface, or a plurality of batteries  2838  can be located on the back surface. Likewise one or more driver ICs  2830  may be located on the back surface to reduce transmission line distance to the microchips. 
       FIG.  29    illustrates an exemplary device  10  with a rollable display  14 . The display  14  can be attached to an extension member  2902 . The extension member  2902  is attached to a display  14  at one end and a spool  2904  at the other end.  FIG.  29    illustrates the extension member  2902  in the extended position in which the display  14  extends outside the housing  12  of the device  10 . The spool  2904  can include a spring under tension to allow the display to be retracted into the housing  10 . 
       FIG.  30    illustrates an exemplary device  10  with a rollable display  14 . Similar to  FIG.  29   , the display  14  can be attached to an extension member  3002 . The extension member  3002  is attached to a display  14  at one end and a spool  3004  at the other end.  FIG.  30    illustrates the extension member  3002  in the retracted position in which the display  14  is retracted into the housing  12  of the device  10 . The spool  3004  can include a spring under tension to allow the display to be retracted into the housing  10 . In various embodiments, sensors (e.g., IMU sensors) in the device can detect the device  10  being dropped. Up detecting a predetermined acceleration, the release mechanism allows the extension member  3002  to retract the display  14  into the housing  12 . 
       FIG.  31    is a flowchart of an example process  3100  associated with techniques to protect a display of an electronic device. In some implementations, one or more process blocks of  FIG.  31    may be performed by an electronic device. Additionally, or alternatively, one or more process blocks of  FIG.  31    may be performed by one or more components of device  10 , such as control circuitry  50 , sensors  56 , display  14 , and release mechanism  2704 . In various embodiments, a first display or the second display is an organic light emitting diode display. In various embodiments, the first display and the second display each comprise regions of a foldable display. 
     At  3110 , the process  3100  can include detecting a vertical acceleration of an electronic device. The vertical acceleration can be detected by an accelerometer. In various embodiments, the vertical acceleration can be detected by an IMU. The vertical acceleration can be converted to a numerical value. The value for the vertical acceleration can be stored in a memory of the device. 
     At block  3120 , the process  3100  can include comparing a value of the vertical acceleration of the electronic device against a predetermined threshold. In various embodiments, a predetermined threshold value of acceleration can be stored in a memory. The processor can compare the detected acceleration value with the predetermined threshold value. 
     At block  3130 , the process  3100  can include activating a release mechanism for a hinged connection between a first display and a second display of the electronic device when the value of the vertical acceleration exceeds the predetermined threshold, wherein the activating reduces an angle between the first display and the second display below a threshold angle. In various embodiments, the threshold angle is an angle less than 180 degrees. 
     In various embodiments, the release mechanism comprises a motorized hinge. In various embodiments, the release mechanism comprises a mechanical hinge with a spring-loaded detent. 
     In various embodiments, a mobile device can include one or more memories and one or more processors in communication with the one or more memories and configured to execute instructions stored in the one or more memories to performing operations of a method described above. 
     In various embodiments, a computer-readable medium may store a plurality of instructions that, when executed by one or more processors of a computing device, cause the one or more processors to perform operations of any of the methods described above. 
     Although  FIG.  31    shows example steps of process  3100 , in some implementations, process  3100  can include additional steps, fewer steps, different steps, or differently arranged steps than those depicted in  FIG.  31   . Additionally, or alternatively, two or more of the steps of process  3100  can be performed in parallel. 
       FIG.  32    is a block diagram of an example electronic device  3200 . Device  3200  generally includes computer-readable medium  3202 , control circuitry  3204 , an Input/Output (I/O) subsystem  3206 , wireless circuitry  3208 , and audio circuitry  3210  including speaker  3250  and microphone  3252 . These components may be coupled by one or more communication buses or signal lines  3203 . Device  3200  can be any portable electronic device, including a handheld computer, a tablet computer, a mobile phone, laptop computer, tablet device, media player, personal digital assistant (PDA), a key fob, a car key, an access card, a multifunction device, a mobile phone, a portable gaming device, a headset, or the like, including a combination of two or more of these items. 
     It should be apparent that the architecture shown in  FIG.  32    is only one example of an architecture for device  3200 , and that device  3200  can have more or fewer components than shown, or a different configuration of components. The various components shown in  FIG.  32    can be implemented in hardware, software, or a combination of both hardware and software, including one or more signal processing and/or application specific integrated circuits. 
     Wireless circuitry  3208  is used to send and receive information over a wireless link or network to one or more other devices&#39; conventional circuitry such as an antenna system, a radio frequency (RF) transceiver, one or more amplifiers, a tuner, one or more oscillators, a digital signal processor, a CODEC chipset, memory, etc. Wireless circuitry  3208  can use various protocols, e.g., as described herein. In various embodiments, wireless circuitry  3208  is capable of establishing and maintaining communications with other devices using one or more communication protocols, including time division multiple access (TDMA), code division multiple access (CDMA), global system for mobile communications (GSM), Enhanced Data GSM Environment (EDGE), wideband code division multiple access (W-CDMA), Long Term Evolution (LTE), Long-term Evolution (LTE)-Advanced, Wi-Fi (such as Institute of Electrical and Electronics Engineers (IEEE) 802.11a, IEEE 802.11b, IEEE 802.11g and/or IEEE 802.11n), Bluetooth, Wi-MAX, voice over Internet Protocol (VoIP), near field communication protocol (NFC), a protocol for email, instant messaging, and/or a short message service (SMS), or any other suitable communication protocol, including communication protocols not yet developed as of the filing date of this document. 
     Wireless circuitry  3208  is coupled to control circuitry  3204  via peripherals interface  3216 . Peripherals interface  3216  can include conventional components for establishing and maintaining communication between peripherals and. Voice and data information received by wireless circuitry  3208  (e.g., in speech recognition or voice command applications) is sent to one or more processors  3218  via peripherals interface  3216 . One or more processors  3218  are configurable to process various data formats for one or more application programs  3234  stored on medium  3202 . 
     Peripherals interface  3216  couple the input and output peripherals of device  3200  to the one or more processors  3218  and computer-readable medium  3202 . One or more processors  3218  communicate with computer-readable medium  3202  via a controller  3220 . Computer-readable medium  3202  can be any device or medium that can store code and/or data for use by one or more processors  3218 . Computer-readable medium  3202  can include a memory hierarchy, including cache, main memory, and secondary memory. The memory hierarchy can be implemented using any combination of RAM (e.g., Standard Random Access Memory (SRAM), Dynamic Random Access Memory (DRAM), Double Data Random Access Memory (DDRAM), Read only Memory (ROM), FLASH, magnetic and/or optical storage devices, such as disk drives, magnetic tape, CDs (compact disks) and DVDs (digital video discs)). In some embodiments, peripherals interface  3216 , one or more processors  3218 , and controller  3220  can be implemented on a single chip, such as control circuitry  3204 . In some other embodiments, they can be implemented on separate chips. 
     Processor(s)  3218  can include hardware and/or software elements that perform one or more processing functions, such as mathematical operations, logical operations, data manipulation operations, data transfer operations, controlling the reception of user input, controlling output of information to users, or the like. Processor(s)  3218  can be embodied as one or more hardware processors, microprocessors, microcontrollers; field programmable gate arrays (FPGAs), application-specified integrated circuits (ASICs), or the like. 
     Device  3200  may include storage and processing circuitry such as control circuitry  3204 . Control circuitry  3204  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 control circuitry  3204  may be used to control the operation of device  3200 . This processing circuitry may be based on one or more microprocessors, microcontrollers, digital signal processors, baseband processor integrated circuits, application specific integrated circuits, etc. 
     Control circuitry  3204  may be used to run software on device  3200 , 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, control circuitry  3204  may be used in implementing communications protocols. Communications protocols that may be implemented using control circuitry  3204  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, satellite navigation system protocols, millimeter wave communications protocols, IEEE 802.15.4 ultra-wideband communications protocols, etc. 
     Device  3200  may include input/output subsystem  3206 . Input/output subsystem  3206  may include input-output devices. Input/output devices may be used to allow data to be supplied to device  3200  and to allow data to be provided from device  3200  to external devices. Input/output devices may include user interface devices, data port devices, and other input-output components. For example, input/output devices may include one or more displays (e.g., touch screens or displays without touch sensor capabilities), one or more image sensors  3244  (e.g., digital image sensors), motion sensors, and speakers  3250 . Input-output device may also include buttons, joysticks, scrolling wheels, touch pads, key pads, keyboards, microphones  3252 , haptic elements such as vibrators and actuators, status indicators, light sources, audio jacks and other audio port components, digital data port devices, light sensors, capacitance sensors, proximity sensors (e.g., a capacitive proximity sensor and/or an infrared proximity sensor), magnetic sensors, and other sensors and input-output components. 
     Device  3200  also includes a power system  3242  for powering the various hardware components. Power system  3242  can include a power management system, one or more power sources (e.g., battery, alternating current (AC)), a recharging system, a power failure detection circuit, a power converter or inverter, a power status indicator (e.g., a light emitting diode (LED)) and any other components typically associated with the generation, management and distribution of power in mobile devices. 
     In some embodiments, device  3200  includes an image sensor  3244  (e.g., a camera). In some embodiments, device  3200  includes sensors  3246 . Sensors can include accelerometers, compass, gyrometer, pressure sensors, audio sensors, light sensors, barometers, and the like. Sensors  3246  can be used to sense location aspects, such as auditory or light signatures of a location. 
     In some embodiments, device  3200  can include a Global Positioning System (GPS) receiver, sometimes referred to as a GPS unit  3248 . A mobile device can use a satellite navigation system, such as the GPS, to obtain position information, timing information, altitude, or other navigation information. During operation, the GPS unit can receive signals from GPS satellites orbiting the Earth. The GPS unit analyzes the signals to make a transit time and distance estimation. The GPS unit can determine the current position (current location) of the mobile device. Based on these estimations, the mobile device can determine a location fix, altitude, and/or current speed. A location fix can be geographical coordinates such as latitudinal and longitudinal information. 
     One or more processors  3218  run various software components stored in medium  3202  to perform various functions for device  3200 . In some embodiments, the software components include an operating system  3222 , a communication module  3224  (or set of instructions), a location module  3226  (or set of instructions), a ranging module  3228  that is used as part of ranging operation described herein, and other application programs  3234  (or set of instructions). 
     Operating system  3222  can be any suitable operating system, including iOS, Mac OS, Darwin, Quatros Real-Time Operating System (RTXC), LINUX, UNIX, OS X, WINDOWS, or an embedded operating system such as VxWorks. The operating system can include various procedures, sets of instructions, software components, and/or drivers for controlling and managing general system tasks (e.g., memory management, storage device control, power management, etc.) and facilitates communication between various hardware and software components. 
     Communication module  3224  facilitates communication with other devices over one or more external ports  3236  or via wireless circuitry  3208  and includes various software components for handling data received from wireless circuitry  3208  and/or external port  3236 . External port  3236  (e.g., universal serial bus (USB), FireWire, Lightning connector,  60 -pin connector, etc.) is adapted for coupling directly to other devices or indirectly over a network (e.g., the Internet, wireless local area network (LAN), etc.). 
     Location/motion module  3226  can assist in determining the current position (e.g., coordinates or other geographic location identifiers) and motion of device  3200 . Modern positioning systems include satellite based positioning systems, such as Global Positioning System (GPS), cellular network positioning based on “cell IDs,” and Wi-Fi positioning technology based on a Wi-Fi networks. GPS also relies on the visibility of multiple satellites to determine a position estimate, which may not be visible (or have weak signals) indoors or in “urban canyons.” In some embodiments, location/motion module  3226  receives data from GPS unit  3248  and analyzes the signals to determine the current position of the mobile device. In some embodiments, location/motion module  3226  can determine a current location using Wi-Fi or cellular location technology. For example, the location of the mobile device can be estimated using knowledge of nearby cell sites and/or Wi-Fi access points with knowledge also of their locations. Information identifying the Wi-Fi or cellular transmitter is received at wireless circuitry  3208  and is passed to location/motion module  3226 . In some embodiments, the location module receives the one or more transmitter IDs. In some embodiments, a sequence of transmitter IDs can be compared with a reference database (e.g., Cell ID database, Wi-Fi reference database) that maps or correlates the transmitter IDs to position coordinates of corresponding transmitters, and computes estimated position coordinates for device  3200  based on the position coordinates of the corresponding transmitters. Regardless of the specific location technology used, location/motion module  3226  receives information from which a location fix can be derived, interprets that information, and returns location information, such as geographic coordinates, latitude/longitude, or other location fix data. 
     Ranging module  3228  can send/receive ranging messages to/from an antenna, e.g., connected to wireless circuitry  3208 . The messages can be used for various purposes, e.g., to identify a sending antenna of a device, determine timestamps of messages to determine a distance of mobile device  3200  from another device. Ranging module  3228  can exist on various processors of the device, e.g., an always-on processor (AOP), a UWB chip, and/or an application processor. For example, parts of ranging module  3228  can determine a distance on an AOP, and another part of the ranging module can interact with a sharing module, e.g., to display a position of the other device on a screen in order for a user to select the other device to share a data item. Ranging module  3228  can also interact with a reminder module that can provide an alert based on a distance from another mobile device. 
     Dielectric-filled openings such as plastic-filled openings may be formed in metal portions of housing such as in metal sidewall structures (e.g., to serve as antenna windows and/or to serve as gaps that separate portions of antennas from each other). 
     Antennas may be mounted in housing. If desired, some of the antennas (e.g., antenna arrays that may implement beam steering, etc.) may be mounted under dielectric portions of device  3200  (e.g., portions of the display cover layer, portions of a plastic antenna window in a metal housing sidewall portion of housing, etc.). With one illustrative configuration, some or all of rear face of device  3200  may be formed from a dielectric. For example, the rear wall of housing may be formed from glass plastic, ceramic, other dielectric. In this type of arrangement, antennas may be mounted within the interior of device  3200  in a location that allows the antennas to transmit and receive antenna signals through the rear wall of device  3200  (and, if desired, through optional dielectric sidewall portions in housing). Antennas may also be formed from metal sidewall structures in housing and may be located in peripheral portions of device  3200 . 
     To avoid disrupting communications when an external object such as a human hand or other body part of a user blocks one or more antennas, antennas may be mounted at multiple locations in housing. Sensor data such as proximity sensor data, real-time antenna impedance measurements, signal quality measurements such as received signal strength information, and other data may be used in determining when one or more antennas is being adversely affected due to the orientation of housing, blockage by a user&#39;s hand or other external object, or other environmental factors. Device  3200  can then switch one or more replacement antennas into use in place of the antennas that are being adversely affected. 
     Antennas may be mounted at the corners of housing, along the peripheral edges of housing, on the rear of housing, under the display cover layer that is used in covering and protecting display on the front of device  3200  (e.g., a glass cover layer, a sapphire cover layer, a plastic cover layer, other dielectric cover layer structures, etc.), under a dielectric window on a rear face of housing or the edge of housing, under a dielectric rear wall of housing, or elsewhere in device  3200 . As an example, antennas may be mounted at one or both ends of device  3200  (e.g., along the upper and lower edges of housing, at the corners of housing, etc.). 
     Antennas in device  3200  may include cellular telephone antennas, wireless local area network antennas (e.g., Wi-Fi® antennas at 2.4 GHz and 5 GHz and other suitable wireless local area network antennas), satellite navigation system signals, and near-field communications antennas. The antennas may also include antennas that support IEEE 802.15.4 ultra-wideband communications protocols and/or antennas for handling millimeter wave communications. For example, the antennas may include two or more ultra-wideband frequency antennas and/or millimeter wave phased antenna arrays. Millimeter wave communications, which are sometimes referred to as extremely high frequency (EHF) communications, involve signals at 60 GHz or other frequencies between about 10 GHz and 400 GHz. 
     Wireless circuitry in device  3200  may support communications using the IEEE 802.15.4 ultra-wideband protocol. In an IEEE 802.15.4 system, a pair of devices may exchange wireless time stamped messages. Time stamps in the messages may be analyzed to determine the time of flight of the messages and thereby determine the distance (range) between the devices. 
     Image sensors  3244  may include one or more visible digital image sensors (visible-light cameras) and/or one or more infrared digital image sensors (infrared-light cameras). Image sensors  3244  may, if desired, be used to measure distances. For example, an infrared time-of-flight image sensor may be used to measure the time that it takes for an infrared light pulse to reflect back from objects in the vicinity of device  3200 , which may in turn be used to determine the distance to those objects. Visible imaging systems such as a front and/or rear-facing camera in device  3200  may also be used to determine the position of objects in the environment. For example, control circuitry  3204  may use image sensors  3244  to perform simultaneous localization and mapping (SLAM). SLAM refers to the process of using images to determine the position of objections in the environment while also constructing a representation of the imaged environment. Visual SLAM techniques include detecting and tracking certain features in images such as edges, textures, room corners, window corners, door corners, faces, sidewalk edges, street edges, building edges, tree trunks, and other prominent features. Control circuitry  3204  may rely entirely upon image sensors  3244  to perform simultaneous localization and mapping, or control circuitry  3204  may synthesize image data with range data from one or more distance sensors (e.g., light-based proximity sensors). If desired, control circuitry  3204  may use display to display a visual representation of the mapped environment. 
     Input-output devices may include motion sensor circuitry  3246 . Motion sensor circuitry  3246  may include one or more accelerometers (e.g., accelerometers that measure acceleration along one, two, or three axes), gyroscopes, barometers, magnetic sensors (e.g., compasses), image sensors (e.g., image sensor  3244 ) and other sensor structures. Sensors  3246  may, for example, include one or more microelectromechanical systems (MEMS) sensors (e.g., accelerometers, gyroscopes, microphones, force sensors, pressure sensors, capacitive sensors, or any other suitable type of sensor formed using microelectromechanical systems technology). 
     Control circuitry  3204  may be used to store and process motion sensor data. If desired, motion sensors, processing circuitry, and storage that form motion sensor circuitry may form part of a system-on-chip integrated circuit (as an example). 
     Input-output devices may include movement generation circuitry. Movement generation circuitry may receive control signals from control circuitry  3204 . Movement generation circuitry may include electromechanical actuator circuitry that, when driven, moves device  3200  in one or more directions. For example, movement generation circuitry may laterally move device  3200  and/or may rotate device  3200  around one or more axes of rotation. Movement generation circuitry may, for example, include one or more actuators formed at one or more locations of device  3200 . When driven by a motion control signal, actuators may move (e.g., vibrate, pulse, tilt, push, pull, rotate, etc.) to cause device  3200  to move or rotate in one or more directions. The movement may be slight (e.g., not noticeable or barely noticeable to a user of device  3200 ), or the movement may be substantial. Actuators may be based on one or more vibrators, motors, solenoids, piezoelectric actuators, speaker coils, or any other desired device capable of mechanically (physically) moving device  3200 . 
     Some or all of movement generation circuitry such as actuators may be used to perform operations that are unrelated to rotation of device  3200 . For example, actuators may include vibrators that are actuated to issue a haptic alert or notification to a user of device  3200 . Such alerts may include, for example, a received text message alert identifying that device  3200  has received a text message, a received telephone call alert, a received email alert, an alarm notification alert, a calendar notification alert, or any other desired notification. By actuating actuator, device  3200  may inform the user of any desired device condition. 
     Motion sensor circuitry may sense motion of device  3200  that is generated by movement generation circuitry. If desired, motion sensor circuitry may provide feedback signals associated with the sensed motion of device  3200  to movement generation circuitry. Movement generation circuitry may use the feedback signals to control actuation of the movement generation circuitry. 
     Control circuitry  3204  may use motion sensor circuitry and/or movement generation circuitry to determine the angle of arrival of wireless signals received by device  3200  from another electronic device. For example, control circuitry  3204  may use movement generation circuitry to move device  3200  from one position to another. Motion sensor circuitry may be used to track the movement of device  3200  as it is moved between the different positions. At each position, control circuitry  3204  may receive wireless signals from another electronic device. Control circuitry  3204  may process the received wireless signals together with the motion data from motion sensor circuitry to more accurately determine the position of the other electronic device. The use of motion generation circuitry is merely illustrative, however. If desired, motion sensor circuitry may track movement of device  3200  that is not caused by motion generation circuitry. This may include a user&#39;s natural, unprompted movement of device  3200  and/or the user&#39;s movement of device  3200  after the user is prompted (by display, audio circuitry  3210 , a haptic output device in device  3200 , or any other suitable output device) to move device  3200  in a particular fashion. 
     Other sensors that may be included in input-output devices include ambient light sensors for gathering information on ambient light levels, proximity sensor components (e.g., light-based proximity sensors, capacitive proximity sensors, and/or proximity sensors based on other structures), depth sensors (e.g., structured light depth sensors that emit beams of light in a grid, a random dot array, or other pattern, and that have image sensors that generate depth maps based on the resulting spots of light produced on target objects), sensors that gather three-dimensional depth information using a pair of stereoscopic image sensors, LIDAR (light detection and ranging) sensors, radar sensors, and other suitable sensors. 
     Input-output circuitry may include wireless communications circuitry for communicating wirelessly with external equipment. Wireless communications circuitry 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  3208  may include radio-frequency transceiver circuitry for handling various radio-frequency communications bands. For example, wireless circuitry  3208  may include transceiver circuitry. 
     Transceiver circuitry may be wireless local area network transceiver circuitry. Transceiver circuitry 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 may use cellular telephone transceiver circuitry for handling wireless communications in frequency ranges such as a communications band from 700 to 960 MHz, a band from 1710 to 2170 MHz, a band from 2300 to 2700 MHz, other bands between 700 and 2700 MHz, higher bands such as LTE bands 42 and 43 (3.4-3.6 GHz), or other cellular telephone communications bands. Circuitry may handle voice data and non-voice data. 
     Millimeter wave transceiver circuitry (sometimes referred to as extremely high frequency transceiver circuitry) may support communications at extremely high frequencies (e.g., millimeter wave frequencies such as extremely high frequencies of 10 GHz to 400 GHz or other millimeter wave frequencies). For example, circuitry may support IEEE 802.11ad communications at 60 GHz. Circuitry may be formed from one or more integrated circuits (e.g., multiple integrated circuits mounted on a common printed circuit in a system-in-package device, one or more integrated circuits mounted on different substrates, etc.). 
     Ultra-wideband transceiver circuitry may support communications using the IEEE 802.15.4 protocol and/or other wireless communications protocols. Ultra-wideband wireless signals may be characterized by bandwidths greater than 500 MHz or bandwidths exceeding 20% of the center frequency of radiation. The presence of lower frequencies in the baseband may allow ultra-wideband signals to penetrate through objects such as walls. Transceiver circuitry may operate in a 2.4 GHz frequency band, a 6.5 GHz frequency band, an 8 GHz frequency band, and/or at other suitable frequencies. 
     Wireless communications circuitry may include satellite navigation system circuitry such as Global Positioning System (GPS) receiver circuitry for receiving GPS signals at 3275 MHz or for handling other satellite positioning data (e.g., GLONASS signals at 1609 MHz). Satellite navigation system signals for receiver are received from a constellation of satellites orbiting the earth. 
     In satellite navigation system links, cellular telephone links, and other long-range links, wireless signals are typically used to convey data over thousands of feet or miles. In Wi-Fi® and Bluetooth® links at 2.4 and 5 GHz and other short-range wireless links, wireless signals are typically used to convey data over tens or hundreds of feet. Extremely high frequency (EHF) wireless transceiver circuitry may convey signals over these short distances that travel between transmitter and receiver over a line-of-sight path. To enhance signal reception for millimeter wave communications, phased antenna arrays and beam steering techniques may be used (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 the antennas that have become blocked or that are otherwise degraded due to the operating environment of device  3200  can be switched out of use and higher-performing antennas used in their place. 
     Wireless communications circuitry can include circuitry for other short-range and long-range wireless links if desired. For example, wireless communications circuitry  36  may include circuitry for receiving television and radio signals, paging system transceivers, near field communications (NFC) circuitry, etc. 
     The one or more applications  3234  on device  3200  can include any applications installed on the device  3200 , including without limitation, a browser, address book, contact list, email, instant messaging, social networking, word processing, keyboard emulation, widgets, JAVA-enabled applications, encryption, digital rights management, voice recognition, voice replication, a music player (which plays back recorded music stored in one or more files, such as MP3 or advanced audio codec (AAC) files), etc. 
     There may be other modules or sets of instructions (not shown), such as a graphics module, a time module, etc. For example, the graphics module can include various conventional software components for rendering, animating and displaying graphical objects (including without limitation text, web pages, icons, digital images, animations, and the like) on a display surface. In another example, a timer module can be a software timer. The timer module can also be implemented in hardware. The time module can maintain various timers for any number of events. 
     I/O subsystem  3206  can be coupled to a display system (not shown), which can be a touch-sensitive display. The display displays visual output to the user in a GUI. The visual output can include text, graphics, video, and any combination thereof. Some or all of the visual output can correspond to user-interface objects. A display can use LED (light emitting diode), LCD (liquid crystal display) technology, or LPD (light emitting polymer display) technology, although other display technologies can be used in other embodiments. 
     In some embodiments, I/O subsystem  3206  can include a display and user input devices such as a keyboard, mouse, and/or trackpad. In some embodiments, I/O subsystem  3206  can include a touch-sensitive display. A touch-sensitive display can also accept input from the user based at least part on haptic and/or tactile contact. In some embodiments, a touch-sensitive display forms a touch-sensitive surface that accepts user input. The touch-sensitive display/surface (along with any associated modules and/or sets of instructions in computer-readable medium  3202 ) detects contact (and any movement or release of the contact) on the touch-sensitive display and converts the detected contact into interaction with user-interface objects, such as one or more soft keys, that are displayed on the touch screen when the contact occurs. In some embodiments, a point of contact between the touch-sensitive display and the user corresponds to one or more digits of the user. The user can make contact with the touch-sensitive display using any suitable object or appendage, such as a stylus, pen, finger, and so forth. A touch-sensitive display surface can detect contact and any movement or release thereof using any suitable touch sensitivity technologies, including capacitive, resistive, infrared, and surface acoustic wave technologies, as well as other proximity sensor arrays or other elements for determining one or more points of contact with the touch-sensitive display. 
     Further, I/O subsystem  3206  can be coupled to one or more other physical control devices (not shown), such as pushbuttons, keys, switches, rocker buttons, dials, slider switches, sticks, LEDs, etc., for controlling or performing various functions, such as power control, speaker volume control, ring tone loudness, keyboard input, scrolling, hold, menu, screen lock, clearing and ending communications and the like. In some embodiments, in addition to the touch screen, device  3200  can include a touchpad (not shown) for activating or deactivating particular functions. In some embodiments, the touchpad is a touch-sensitive area of the device  3200  that, unlike the touch screen, does not display visual output. The touchpad can be a touch-sensitive surface that is separate from the touch-sensitive display or an extension of the touch-sensitive surface formed by the touch-sensitive display. 
     In some embodiments, some or all of the operations described herein can be performed using an application executing on the user&#39;s device. Circuits, logic modules, processors, and/or other components may be configured to perform various operations described herein. Those skilled in the art will appreciate that, depending on implementation, such configuration can be accomplished through design, setup, interconnection, and/or programming of the particular components and that, again depending on implementation, a configured component might or might not be reconfigurable for a different operation. For example, a programmable processor can be configured by providing suitable executable code; a dedicated logic circuit can be configured by suitably connecting logic gates and other circuit elements; and so on. 
     Any of the software components or functions described in this application may be implemented as software code to be executed by a processor using any suitable computer language such as, for example, Java, C, C++, C#, Objective-C, Swift, or scripting language such as Perl or Python using, for example, conventional or object-oriented techniques. The software code may be stored as a series of instructions or commands on a computer readable medium for storage and/or transmission. A suitable non-transitory computer readable medium can include random access memory (RAM), a read only memory (ROM), a magnetic medium such as a hard-drive or a floppy disk, or an optical medium, such as a compact disk (CD) or DVD (digital versatile disk), flash memory, and the like. The computer readable medium may be any combination of such storage or transmission devices. 
     Computer programs incorporating various features of the present disclosure may be encoded on various computer readable storage media; suitable media include magnetic disk or tape, optical storage media, such as compact disk (CD) or DVD (digital versatile disk), flash memory, and the like. Computer readable storage media encoded with the program code may be packaged with a compatible device or provided separately from other devices. In addition, program code may be encoded and transmitted via wired optical, and/or wireless networks conforming to a variety of protocols, including the Internet, thereby allowing distribution, e.g., via Internet download. Any such computer readable medium may reside on or within a single computer product (e.g. a solid state drive, a hard drive, a CD, or an entire computer system), and may be present on or within different computer products within a system or network. A computer system may include a monitor, printer, or other suitable display for providing any of the results mentioned herein to a user. 
     As described above, one aspect of the present technology is the gathering, sharing, and use of data available from specific and legitimate sources to improve the delivery to users of invitational content or any other content that may be of interest to them. The present disclosure contemplates that in some instances, this gathered data may include personal information data that uniquely identifies or can be used to contact or locate a specific person. Such personal information data can include demographic data, location-based data, telephone numbers, email addresses, twitter ID&#39;s, home addresses, data or records relating to a user&#39;s health or level of fitness (e.g., vital signs measurements, medication information, exercise information), date of birth, or any other identifying or personal information. 
     The present disclosure recognizes that the use of such personal information data, in the present technology, can be used to the benefit of users. For example, the personal information data can be used to authenticate another device, and vice versa to control which devices ranging operations may be performed. Further, other uses for personal information data that benefit the user are also contemplated by the present disclosure. For instance, health and fitness data may be shared to provide insights into a user&#39;s general wellness, or may be used as positive feedback to individuals using technology to pursue wellness goals. 
     The present disclosure contemplates that the entities responsible for the collection, analysis, disclosure, transfer, storage, or other use of such personal information data will comply with well-established privacy policies and/or privacy practices. In particular, such entities should implement and consistently use privacy policies and practices that are generally recognized as meeting or exceeding industry or governmental requirements for maintaining personal information data private and secure. Such policies should be easily accessible by users, and should be updated as the collection and/or use of data changes. Personal information from users should be collected for legitimate and reasonable uses of the entity and not shared or sold outside of those legitimate uses. Further, such collection/sharing should occur after receiving the informed consent of the users. Additionally, such entities should consider taking any needed steps for safeguarding and securing access to such personal information data and ensuring that others with access to the personal information data adhere to their privacy policies and procedures. Further, such entities can subject themselves to evaluation by third parties to certify their adherence to widely accepted privacy policies and practices. In addition, policies and practices should be adapted for the particular types of personal information data being collected and/or accessed and adapted to applicable laws and standards, including jurisdiction-specific considerations. For instance, in the US, collection of or access to certain health data may be governed by federal and/or state laws, such as the Health Insurance Portability and Accountability Act (HIPAA); whereas health data in other countries may be subject to other regulations and policies and should be handled accordingly. Hence, different privacy practices should be maintained for different personal data types in each country. 
     Despite the foregoing, the present disclosure also contemplates embodiments in which users selectively block the use of, or access to, personal information data. That is, the present disclosure contemplates that hardware and/or software elements can be provided to prevent or block access to such personal information data. For example, in the case of sharing content and performing ranging, the present technology can be configured to allow users to select to “opt in” or “opt out” of participation in the collection of personal information data during registration for services or anytime thereafter. In addition to providing “opt in” and “opt out” options, the present disclosure contemplates providing notifications relating to the access or use of personal information. For instance, a user may be notified upon downloading an app that their personal information data will be accessed and then reminded again just before personal information data is accessed by the app. 
     Moreover, it is the intent of the present disclosure that personal information data should be managed and handled in a way to minimize risks of unintentional or unauthorized access or use. Risk can be minimized by limiting the collection of data and deleting data once it is no longer needed. In addition, and when applicable, including in certain health related applications, data de-identification can be used to protect a user&#39;s privacy. De-identification may be facilitated, when appropriate, by removing specific identifiers (e.g., date of birth, etc.), controlling the amount or specificity of data stored (e.g., collecting location data a city level rather than at an address level), controlling how data is stored (e.g., aggregating data across users), and/or other methods. 
     Therefore, although the present disclosure broadly covers use of personal information data to implement one or more various disclosed embodiments, the present disclosure also contemplates that the various embodiments can also be implemented without the need for accessing such personal information data. That is, the various embodiments of the present technology are not rendered inoperable due to the lack of all or a portion of such personal information data. 
     Although the present disclosure has been described with respect to specific embodiments, it will be appreciated that the disclosure is intended to cover all modifications and equivalents within the scope of the following claims. 
     The specification and drawings are, accordingly, to be regarded in an illustrative rather than a restrictive sense. It will, however, be evident that various modifications and changes may be made thereunto without departing from the broader spirit and scope of the disclosure as set forth in the claims. 
     Other variations are within the spirit of the present disclosure. Thus, while the disclosed techniques are susceptible to various modifications and alternative constructions, certain illustrated embodiments thereof are shown in the drawings and have been described above in detail. It should be understood, however, that there is no intention to limit the disclosure to the specific form or forms disclosed, but on the contrary, the intention is to cover all modifications, alternative constructions and equivalents falling within the spirit and scope of the disclosure, as defined in the appended claims. 
     The use of the terms “a” and “an” and “the” and similar referents in the context of describing the disclosed embodiments (especially in the context of the following claims) are to be construed to cover both the singular and the plural, unless otherwise indicated herein or clearly contradicted by context. The terms “comprising,” “having,” “including,” and “containing” are to be construed as open-ended terms (i.e., meaning “including, but not limited to,”) unless otherwise noted. The term “connected” is to be construed as partly or wholly contained within, attached to, or joined together, even if there is something intervening. The phrase “based on” should be understood to be open-ended, and not limiting in any way, and is intended to be interpreted or otherwise read as “based at least in part on,” where appropriate. Recitation of ranges of values herein are merely intended to serve as a shorthand method of referring individually to each separate value falling within the range, unless otherwise indicated herein, and each separate value is incorporated into the specification as if it were individually recited herein. All methods described herein can be performed in any suitable order unless otherwise indicated herein or otherwise clearly contradicted by context. The use of all examples, or exemplary language (e.g., “such as”) provided herein, is intended merely to better illuminate embodiments of the disclosure and does not pose a limitation on the scope of the disclosure unless otherwise claimed. No language in the specification should be construed as indicating any non-claimed element as essential to the practice of the disclosure. The use of “or” is intended to mean an “inclusive or,” and not an “exclusive or” unless specifically indicated to the contrary. Reference to a “first” component does not necessarily require that a second component be provided. Moreover, reference to a “first” or a “second” component does not limit the referenced component to a particular location unless expressly stated. The term “based on” is intended to mean “based at least in part on.” 
     Disjunctive language such as the phrase “at least one of X, Y, or Z,” unless specifically stated otherwise, is otherwise understood within the context as used in general to present that an item, term, etc., may be either X, Y, or Z, or any combination thereof (e.g., X, Y, and/or Z). Thus, such disjunctive language is not generally intended to, and should not, imply that certain embodiments require at least one of X, at least one of Y, or at least one of Z to each be present. Additionally, conjunctive language such as the phrase “at least one of X, Y, and Z,” unless specifically stated otherwise, should also be understood to mean X, Y, Z, or any combination thereof, including “X, Y, and/or Z.” 
     Preferred embodiments of this disclosure are described herein, including the best mode known to the inventors for carrying out the disclosure. Variations of those preferred embodiments may become apparent to those of ordinary skill in the art upon reading the foregoing description. The inventors expect skilled artisans to employ such variations as appropriate, and the inventors intend for the disclosure to be practiced otherwise than as specifically described herein. Accordingly, this disclosure includes all modifications and equivalents of the subject matter recited in the claims appended hereto as permitted by applicable law. Moreover, any combination of the above-described elements in all possible variations thereof is encompassed by the disclosure unless otherwise indicated herein or otherwise clearly contradicted by context. 
     All references, including publications, patent applications, and patents, cited herein are hereby incorporated by reference to the same extent as if each reference were individually and specifically indicated to be incorporated by reference and were set forth in its entirety herein. 
     Any of the software components or functions described in this application, may be implemented as software code to be executed by a processor using any suitable computer language such as, for example, Java, C++ or Perl using, for example, conventional or object-oriented techniques. The software code may be stored as a series of instructions, or commands on a computer readable medium for storage and/or transmission, suitable media include random access memory (RAM), a read only memory (ROM), a magnetic medium such as a hard-drive or a floppy disk, or an optical medium such as a compact disk (CD) or DVD (digital versatile disk), flash memory, and the like. The computer readable medium may be any combination of such storage or transmission devices. 
     Such programs may also be encoded and transmitted using carrier signals adapted for transmission via wired, optical, and/or wireless networks conforming to a variety of protocols, including the Internet. As such, a computer readable medium according to an embodiment of the present invention may be created using a data signal encoded with such programs. Computer readable media encoded with the program code may be packaged with a compatible device or provided separately from other devices (e.g., via Internet download). Any such computer readable medium may reside on or within a single computer program product (e.g. a hard drive or an entire computer system), and may be present on or within different computer program products within a system or network. A computer system may include a monitor, printer, or other suitable display for providing any of the results mentioned herein to a user. 
     The specific details of particular embodiments may be combined in any suitable manner or varied from those shown and described herein without departing from the spirit and scope of embodiments of the invention. 
     The above description of exemplary embodiments of the invention has been presented for the purposes of illustration and description. It is not intended to be exhaustive or to limit the invention to the precise form described, and many modifications and variations are possible in light of the teaching above. The embodiments were chosen and described in order to best explain the principles of the invention and its practical applications to thereby enable others skilled in the art to best utilize the invention in various embodiments and with various modifications as are suited to the particular use contemplated. 
     All publications, patents, and patent applications cited herein are hereby incorporated by reference in their entirety for all purposes.

Metadata:
Filing Date: 20220202
Publication Date: 20241217
Grant Date: 20241217
Priority Date: 20210914
Inventors: KIM, HOON SIK
WITTENBERG, MICHAEL B.
Assignee: APPLE INC
CPC Classifications: [{"code": "G06F1/1679", "inventive": true, "first": false, "tree": "[]"}, {"code": "G09F9/335", "inventive": true, "first": false, "tree": "[]"}, {"code": "G06F2200/1637", "inventive": false, "first": false, "tree": "[]"}, {"code": "G06F1/1681", "inventive": true, "first": false, "tree": "[]"}, {"code": "G06F2200/1633", "inventive": false, "first": false, "tree": "[]"}, {"code": "G06F1/1679", "inventive": true, "first": false, "tree": "[]"}, {"code": "G06F1/1694", "inventive": true, "first": false, "tree": "[]"}, {"code": "G06F1/1684", "inventive": true, "first": false, "tree": "[]"}, {"code": "G06F1/1615", "inventive": true, "first": false, "tree": "[]"}, {"code": "G06F1/1652", "inventive": true, "first": true, "tree": "[]"}, {"code": "G06F1/1652", "inventive": true, "first": true, "tree": "[]"}, {"code": "G06F2200/1637", "inventive": false, "first": false, "tree": "[]"}, {"code": "G06F2200/1633", "inventive": false, "first": false, "tree": "[]"}, {"code": "G09F9/335", "inventive": true, "first": false, "tree": "[]"}, {"code": "G06F1/1681", "inventive": true, "first": false, "tree": "[]"}, {"code": "G06F1/1679", "inventive": true, "first": false, "tree": "[]"}, {"code": "G06F1/1652", "inventive": true, "first": true, "tree": "[]"}]
Family ID: 85480058