Abstract: An electronic device, such as a watch, has a housing to which a carrier is attached. The carrier has a first surface interior to the electronic device, and a second surface exterior to the electronic device. A set of electrodes is deposited on the exterior surface of the carrier. An additional electrode is operable to be contacted by a finger of a user of the electronic device while the first electrode is positioned against skin of the user. The additional electrode may be positioned on a user-rotatable crown of the electronic device, on a button of the electronic device, or on another surface of the housing of the electronic device. A processor of the electronic device is operable to determine a biological parameter of the user based on voltages at the electrodes. The biological parameter may be an electrocardiogram.

Abstract: A modular sensing assembly may be used to detect user inputs at an electronic device. Example user inputs include touch inputs, fingerprint inputs, translational inputs, audio inputs, biometric inputs, and the like. Inputs received using the modular sensing assembly may be used to control a graphical output of a display of the electronic device. A modular sensing assembly may be configured, for example, as a power button, a key of a keyboard, a control button (e.g., volume control), a home button, a watch crown, and so on.

Abstract: Wearable electronic devices, such as smart watches, can be provided with a band for securing the device to a wearer. The device and the band can include near-field communications (NFC) components that allow the device to uniquely identify the band. Device operations such as the color, theme, or content displayed on the device can be based, in part, on the identification of a particular band. The band may include a miniature NFC tag in an attachment portion of the band that is configured to be received in a recess in a housing of the device. An NFC module for reading the NFC tag can be provided within the recess of the housing, so that the attachment portion of the band and the recess in the device housing position and align the NFC tag with the NFC module when the band is attached to the device.

Abstract: An electronic device may have light-emitting devices. A light-emitting device may include light-emitting diodes, a display, or other components that emit visual output. One or more image transport layers may be included in the electronic device. An image transport layer may have an input surface that receives an image and an output surface to which the image transport layer transports the image for viewing by a user. The image transport layers may have areas with compound curvature and other shapes. Deformed image transport layer structures such as deformed fibers in a coherent fiber bundle may be configured to hide gaps in displays and other structures. Displays may include light detectors that serve as a two-dimensional touch sensor. The touch sensor may detect touch input on an output surface of an image transport layer. Image transport layer material may be incorporated into buttons, elongated housings, wearable devices, and other equipment.

Abstract: An electronic device, such as a watch, has a housing to which a carrier is attached. The carrier has a first surface interior to the electronic device, and a second surface exterior to the electronic device. A set of electrodes is deposited on the exterior surface of the carrier. An additional electrode is operable to be contacted by a finger of a user of the electronic device while the first electrode is positioned against skin of the user. The additional electrode may be positioned on a user-rotatable crown of the electronic device, on a button of the electronic device, or on another surface of the housing of the electronic device. A processor of the electronic device is operable to determine a biological parameter of the user based on voltages at the electrodes. The biological parameter may be an electrocardiogram.

Abstract: A case for a round electronic device may have a device holding portion and an attachment portion for attaching the case to an item such as a suitcase or a key chain. The case may include upper and lower case portions that form a pocket. On a first side of the pocket, the upper and lower case portions may be stitched together or may be integrally formed. On a second side of the pocket, a snap may attach the upper case portion to the lower case portion and may be opened to provide access to the pocket. The attachment portion may have an opening for attaching the case to a key ring, suitcase, or other item. The case may include leather, polymer, and/or fabric. Openings may be surrounded by reinforcement material such as strands of non-elastic material. Snaps may be flush with surrounding portions of the case.

Abstract: Wearable electronic devices, such as smart watches, can be provided with a band for securing the device to a wearer. The device and the band can include near-field communications (NFC) components that allow the device to uniquely identify the band. Device operations such as the color, theme, or content displayed on the device can be based, in part, on the identification of a particular band. The band may include a miniature NFC tag in an attachment portion of the band that is configured to be received in a recess in a housing of the device. An NFC module for reading the NFC tag can be provided within the recess of the housing, so that the attachment portion of the band and the recess in the device housing position and align the NFC tag with the NFC module when the band is attached to the device.

Abstract: A wireless communication system may include an electronic device having a wireless communication module. The wireless communication module may include an antenna radiating element on a first surface, a ground ring surrounding the antenna radiating element on the first surface, and a radio component mounted to a second surface. The wireless communication module may be incorporated into a system package that also includes other components. Encapsulation material may cover the wireless communication module and other components. A shielding material may cover the encapsulation material and be coupled to the ground ring. An opening in the shielding material may be aligned with the antenna radiating element. If desired, the wireless communication system may include external equipment having a wireless communication module communicatively coupled to the wireless communication module to convey firmware testing, debugging, restore, and/or other data.

Abstract: A watch having a cover is described. An optical sensor subsystem is attached adjacent to or directly on an interior surface of the cover. In some cases, the optical sensor subsystem includes a substrate to which a light emitter and a light receiver are attached. The light receiver is configured to receive light emitted by the light emitter and reflected from the skin of a person that wears the watch. In some cases, the light emitter and light receiver are separated by a light-blocking wall that abuts the interior surface of the cover. In some cases, a light filter is attached adjacent or directly on the interior surface of the cover, between the cover and the light receiver.

Abstract: An electronic device may have a display and other optical components such as optical sensors. The display and other components may be overlapped by chemically strengthened glass coherent fiber bundles. The surfaces of a coherent fiber bundle may include ion-exchanged glass that places theses surfaces under compressive stress. In some configurations, the coherent fiber bundle is symmetrically stressed and has equal amounts of compressive stress on opposing surfaces. In other configurations, the coherent fiber bundle is asymmetrically stressed and has more compressive stress on one surface than the other. The coherent fiber bundle may have areas with curved cross-sectional profiles, planar areas, and/or areas with compound curvature. Sensor windows may be formed in the coherent fiber bundle that are surrounded by an opaque area. When overlapping a display, the coherent fiber bundle may serve as a display cover glass layer.

Abstract: An electronic device may have a display overlapped by an image transport layer such as a coherent fiber bundle or layer of Anderson localization material. The image transport layer may have an input surface that receives an image from the display and a corresponding output surface to which the image is transported. The input surface and output surface may have different shapes. During fabrication of the image transport layer, a peripheral portion of the image transport layer may be laterally indented to form a peripheral recess. Electrical components such as optical and radio-frequency components may be mounted in the recess and may be overlapped by peripheral portions of the image transport layer and/or may be mounted under the display.

Abstract: An electronic watch includes a housing and a crown assembly including a rotatable actuation member. The rotatable actuation member includes a knob external to the housing and configured to receive a rotational input and a shaft assembly coupled to the knob and positioned at least partially within the housing, the shaft assembly defining a sensing surface configured to rotate in response to the rotational input. The electronic watch further includes an optical sensing system configured to detect the rotational input, the detecting including directing light onto the sensing surface, receiving reflected light from the sensing surface, and producing a signal corresponding to a rotational motion of the sensing surface, the signal based at least in part on an interference between the light directed onto the sensing surface and the reflected light.

Abstract: A modular sensing assembly may be used to detect user inputs at an electronic device. Example user inputs include touch inputs, fingerprint inputs, translational inputs, audio inputs, biometric inputs, and the like. Inputs received using the modular sensing assembly may be used to control a graphical output of a display of the electronic device. A modular sensing assembly may be configured, for example, as a power button, a key of a keyboard, a control button (e.g., volume control), a home button, a watch crown, and so on.

Abstract: Device localization (e.g., ultra-wideband device localization) may be used to provide coordinated outputs and/or receive coordinated inputs using multiple devices. Providing coordinated outputs may include providing partial outputs using multiple devices, modifying an output of a device based on its position and/or orientation relative to another device, and the like. In some cases, each device of a set of multiple devices may provide a partial output, which combines with partial outputs of the remaining devices to produce a coordinated output.

Abstract: An electronic device may have a housing. A pixel array may be mounted in the housing to display an image. The pixel array may have a central portion surrounded by a peripheral portion. Display cover layer structures may overlap the pixel array. A central portion of the display cover layer structures may overlap the central portion of the pixel array. A peripheral portion of the display cover layer structures may overlap the peripheral portion of the pixel array. A border structure of image transport material may be interposed between the peripheral portion of the pixel array and the peripheral portion of the display cover structures. The image transport material may be omitted from the central portion of the pixel array. The image transport material may be formed from a coherent fiber bundle or Anderson localization material.

Abstract: A watch having a cover is described. An optical sensor subsystem is attached adjacent to or directly on an interior surface of the cover. In some cases, the optical sensor subsystem includes a substrate to which a light emitter and a light receiver are attached. The light receiver is configured to receive light emitted by the light emitter and reflected from the skin of a person that wears the watch. In some cases, the light emitter and light receiver are separated by a light-blocking wall that abuts the interior surface of the cover. In some cases, a light filter is attached adjacent or directly on the interior surface of the cover, between the cover and the light receiver.

Abstract: A watch band is disclosed. The watch band maintains a substantially constant tension throughout changes in its length while worn by a user. Such changes in length may occur automatically to accommodate changes in the size and circumference of a user's wrist as they move their wrist normally. By maintaining a constant tension, the watch band also maintains a constant force on the user's wrist, and causes a watch body attached to the watch band to also maintain a constant force on the user's wrist. This can increase a user's comfort, since the watch will not get tighter or constrict their wrist as they straighten and bend their wrist. It can also help optimize operation of any sensors in the watch band or watch body that benefit from being held against the user's wrist with a constant force, such as some physiological sensors.

Abstract: An electronic device may have a display mounted in a housing. The display may have a display panel with an array of pixels on a flexible substrate. A display cover layer may overlap the display panel. The flexible substrate may have a protruding portion that forms a tail. When the display is mounted in the housing, the tail may be bent back on itself to create a bend. The bend may be embedded in molded polymer. The device may have structures that help prevent the display cover layer from being compressed inwardly towards the rear of the housing such as frame structures embedded in the molded polymer and/or housing sidewall structures. Optical components and optical waveguides may be embedded within the molded polymer. Mating chamfers on the display cover layer and housing may help seat the display cover layer in the housing.

Abstract: An input mechanism, such as a crown, detects amounts of applied force. In various examples, an assembly including an input mechanism has an enclosure; a stem coupled to the enclosure such that the stem is rotatable, translatable, and transversely moveable with respect to the enclosure; a sensor, coupled between the stem and the housing, to which force is transferred when the stem moves with respect to the housing; and a processing unit coupled to the sensor. The processing unit is operable to determine a measurement of the force, based on a signal from the sensor.

Abstract: An electronic device, such as a watch, has a housing to which a carrier is attached. The carrier has a first surface interior to the electronic device, and a second surface exterior to the electronic device. A set of electrodes is deposited on the exterior surface of the carrier. An additional electrode is operable to be contacted by a finger of a user of the electronic device while the first electrode is positioned against skin of the user. The additional electrode may be positioned on a user-rotatable crown of the electronic device, on a button of the electronic device, or on another surface of the housing of the electronic device. A processor of the electronic device is operable to determine a biological parameter of the user based on voltages at the electrodes. The biological parameter may be an electrocardiogram.