Abstract: Various embodiments include a light source module with one or more light emitters and one or more light sensors that share an aperture via which light passes. One of the light sensors may measure illuminance received through the aperture (not illuminance from the light emitters) and send a signal indicating a measurement of the illuminance. The light source module may be integrated into a portable computing device having a controller. The controller may include logic to perform one or more device operations based on the measurement of illuminance, such as, but not limited to, controlling a device display brightness and/or controlling an auto exposure feature of the device camera. Calibration parameters for interpreting the signal may be determined via a calibration process.

Abstract: A head-mounted display may include a display system and an optical system in a housing. The display system may have displays that produce images. Positioners may be used to move the displays relative to the eye positions of a user's eyes. An adjustable optical system may include tunable lenses such as tunable cylindrical liquid crystal lenses. The displays may be viewed through the lenses when the user's eyes are at the eye positions. A sensor may be incorporated into the head-mounted display to measure refractive errors in the user's eyes. The sensor may include waveguides and volume holograms, and a camera for gathering light that has reflected from the retinas of the user's eyes. Viewing comfort may be enhanced by adjusting display positions relative to the eye positions and/or by adjusting lens settings based on the content being presented on the display and/or measured refractive errors.

Abstract: A head-mounted display may include a display system and an optical system in a housing. The display system may have displays that produce images. Positioners may be used to move the displays relative to the eye positions of a user's eyes. An adjustable optical system may include tunable lenses such as tunable cylindrical liquid crystal lenses. The displays may be viewed through the lenses when the user's eyes are at the eye positions. A sensor may be incorporated into the head-mounted display to measure refractive errors in the user's eyes. The sensor may include waveguides and volume holograms, and a camera for gathering light that has reflected from the retinas of the user's eyes. Viewing comfort may be enhanced by adjusting display positions relative to the eye positions and/or by adjusting lens settings based on the content being presented on the display and/or measured refractive errors.

Abstract: A display may have display layers that form an array of pixels. An angle-of-view adjustment layer may overlap the display layers. The angle-of-view adjustment layer may include an array of adjustable light blocking structures formed from electrochromic material. The electrochromic material may be interposed between first and second electrode layers. When it is desired to operate the display in a private viewing mode, control circuitry may apply a current to the first and second electrodes that causes the electrochromic material to become more opaque, thereby restricting the angle of view of the display. When it is desired to operate the display in a public viewing mode, control circuitry may apply a current to the first and second electrodes that causes the electrochromic material to become more transparent, thereby opening up the angle of view of the display.

Abstract: A system may include electronic devices that communicate wirelessly. When positioned so that a pair of devices overlap or are near to one another, the devices may operate in a linked mode. During linked operations, devices may communicate wirelessly while input gathering and content displaying operations are shared among the devices. One or both of a pair of devices may have sensors. An orientation sensor, motion sensor, optical sensor, and/or other sensors may be used in identifying conditions in which to enter the linked mode and to identify a region where displays in the pair of devices overlap.

Abstract: A system may include electronic devices that communicate wirelessly. When positioned so that a pair of devices overlap or are near to one another, the devices may operate in a linked mode. During linked operations, devices may communicate wirelessly while input gathering and content displaying operations are shared among the devices. One or both of a pair of devices may have sensors. An orientation sensor, motion sensor, optical sensor, and/or other sensors may be used in identifying conditions in which to enter the linked mode and to identify a region where displays in the pair of devices overlap.

Abstract: An electronic device such as a cellular telephone or other device may have a housing with front and rear faces joined by a sidewall. A display may be mounted on the front face. The electronic device may include multiple ambient light sensors such as a front ambient light sensor on the front face and one or more supplemental ambient light sensors on the rear face and/or on the sidewall. The front ambient light sensor gathers a front ambient light intensity measurement and the supplemental ambient light sensor gathers a supplemental ambient light intensity measurement. During operation, control circuitry in the electronic device adjusts the display brightness based on data from the ambient light sensors. The control circuitry may implement power saving restrictions that limit when the supplemental ambient light intensity measurement is taken into account and/or that impose a brightness cap on the display brightness.

Abstract: An electronic device such as a cellular telephone or other device may have a housing with front and rear faces joined by a sidewall. A display may be mounted on the front face. The electronic device may include multiple ambient light sensors such as a front ambient light sensor on the front face and one or more supplemental ambient light sensors on the rear face and/or on the sidewall. The front ambient light sensor gathers a front ambient light intensity measurement and the supplemental ambient light sensor gathers a supplemental ambient light intensity measurement. During operation, control circuitry in the electronic device adjusts the display brightness based on data from the ambient light sensors. The control circuitry may implement power saving restrictions that limit when the supplemental ambient light intensity measurement is taken into account and/or that impose a brightness cap on the display brightness.

Abstract: A display may have display layers that form an array of pixels. An angle-of-view adjustment layer may overlap the display layers. The angle-of-view adjustment layer may include an array of adjustable louvers that move from a first position in which the angle of view of the display is restricted for a private viewing mode and a second position in which the angle of view of the display is not restricted for a normal viewing mode. The louvers may contain electrophoretic particles. The louvers may be tapered and may have a width at one end that is less than ten microns. The electrophoretic particles may form isolated clusters on a lower substrate in normal viewing mode to increase the transmittance of the display in normal viewing mode. The angle-of-view adjustment layer may be a second liquid crystal display layer that is used to block off-axis light.

Abstract: An electronic device may include a display for displaying image content to a user and dynamic image stabilization circuitry for dynamically compensating the image content if the device is moving unpredictably to help keep the image content aligned with the user's gaze. The electronic device may include sensors for detecting the displacement of the device. The dynamic image stabilization circuitry may include a usage scenario detection circuit and a content displacement compensation calculation circuit. The usage scenario detection circuit receives data from the sensors and infers a usage scenario based on the sensor data. The content displacement compensation calculation circuit uses the inferred usage scenario to compute a displacement amount by which to adjust image content. When motion stops, the image content may gradually drift back to the center of the display.

Abstract: One exemplary implementation involves performing operations at an electronic device with one or more processors and a computer-readable storage medium. The device establishes a wireless communication link with a host device. The device receives, from the host device, a left eye frame and a right eye frame via a sequence of left eye frame transmissions and right eye frame transmissions. The device switches data transmissions schemes according to wireless commination link quality or eye gaze tracking. Adjusting transmission format based on transmission quality of the wireless communication link allows the devices to take advantage of greater bandwidth when available to save power. An additional transmission format is based on alternately transmitting left eye and right eye frames for very low bandwidth.

Abstract: One exemplary implementation involves performing operations at an electronic device with one or more processors and a computer-readable storage medium. The device establishes a wireless communication link with a host device. The device receives, from the host device, a left eye frame and a right eye frame via a sequence of interleaved left eye frame transmissions and right eye frame transmissions. The device loads the left eye frame into a left eye display device and loads the right eye frame into a right eye display device on the electronic device, where the loading includes sequentially loading left eye frame portions and right eye frame portions as the sequence of interleaved left eye frame transmissions and right eye frame transmissions is received. The device then concurrently displays the left eye frame and the right eye frame at the electronic device. The device switches data transmissions schemes according to wireless communication link quality and eye gaze tracking.

Abstract: A system may include an electronic device and one or more finger devices. The electronic device may have a display and the user may provide finger input to the finger device to control the display. The finger input may include pinching, tapping, rotating, swiping, pressing, and/or other finger gestures that are detected using sensors in the finger device. The sensor data related to finger movement may be combined with user gaze information to control items on the display. The user may turn any surface or region of space into an input region by first defining boundaries of the input region using the finger device. Other finger gestures such as pinching and pulling, pinching and rotating, swiping, and tapping may be used to navigate a menu on a display, to scroll through a document, to manipulate computer-aided designs, and to provide other input to a display.

Abstract: An electronic device may have components that experience performance variations as the device changes orientation relative to a user. Changes in the orientation of the device relative to the user can be monitored using a motion sensor. A camera may be used to periodically capture images of a user's eyes. By processing the images to produce accurate orientation information reflecting the position of the user's eyes relative to the device, the orientation of the device tracked by the motion sensor can be periodically updated. The components may include audio components such as microphones and speakers and may include a display with an array of pixels for displaying images. Control circuitry in the electronic device may modify pixel values for the pixels in the array to compensate for angle-of-view-dependent pixel appearance variations based on based on the orientation information from the motion sensor and the camera.

Abstract: A head-mounted display may include a display system and an optical system in a housing. The display system may have displays that produce images. Positioners may be used to move the displays relative to the eye positions of a user's eyes. An adjustable optical system may include tunable lenses such as tunable cylindrical liquid crystal lenses. The displays may be viewed through the lenses when the user's eyes are at the eye positions. A sensor may be incorporated into the head-mounted display to measure refractive errors in the user's eyes. The sensor may include waveguides and volume holograms, and a camera for gathering light that has reflected from the retinas of the user's eyes. Viewing comfort may be enhanced by adjusting display positions relative to the eye positions and/or by adjusting lens settings based on the content being presented on the display and/or measured refractive errors.

Abstract: An electronic device may have a main display and an ancillary display that forms a dynamic function row. The device may also have a backlit keyboard with glyphs. The keyboard may have light-emitting diodes that emit backlight illumination. The backlight illumination has a backlight illumination color and intensity. A color ambient light sensor may measure ambient light color and intensity. Control circuitry in the laptop computer may make white point adjustments to the main and ancillary displays. White point adjustments may be made based on factors such as the backlight illumination intensity, information on the nominal white point of a display (which may be comparable to the color of the backlight illumination), information on the ambient light color and intensity, and a white point adaptation scaling factor.

Abstract: An electronic device may be provided with a display mounted in a housing. Color ambient light sensors may make measurements of ambient light intensity and color through windows in an inactive border region of the display or other portions of the device. The electronic device may process the ambient light measurements based on ambient light information from the ambient light sensors and based on information from additional sensors such as an image sensor, a force sensor, a capacitive touch sensor, a proximity sensor, an orientation sensor, and other devices. Control circuitry in the electronic device may produce reliable ambient light measurements by combining readings from multiple reliable sources and by discarding readings from ambient light sensors that are blocked by a user's fingers or other external objects. Display color cast and intensity may be adjusted based on ambient light information.

Abstract: An electronic device such as a desktop computer or other device may have an electronic device housing with front and rear faces. A display may be mounted on the front face. The electronic device may include multiple ambient light sensors such as a front color ambient light sensor on the front face and a rear color ambient light sensor on the rear face. The front ambient light sensor gathers a front ambient light intensity measurement and a front ambient light color measurement. The rear ambient light sensor gathers a rear ambient light intensity measurement and a rear ambient light color measurement. During operation, control circuitry in the electronic device takes action based on data from the ambient light sensors. The control circuitry may adjust a white point of the display using a combined color value that is produced using a combining function.

Abstract: An electronic device may have a display. Input-output circuitry in the electronic device may be used to gather input from a viewer of the display. The input-output circuitry may include a gaze tracking system that gathers point-of-gaze information, vergence information, and head position information, may be a biometric sensor, may be an input device such as a button or touch sensor, may capture hand gestures, and/or may gather other information. The display may include a pixel array for producing images. An adjustable reflectance and transmittance layer may overlap the pixel array. Control circuitry in the electronic device may individually adjust different areas of the adjustable reflectance and transmittance layer. The control circuitry may place each area in a reflective mirror more or in a content-displaying mode and may move the areas in response to the information.

Abstract: An electronic device may include a display for displaying image content to a user and dynamic image stabilization circuitry for dynamically compensating the image content if the device is moving unpredictably to help keep the image content aligned with the user's gaze. The electronic device may include sensors for detecting the displacement of the device. The dynamic image stabilization circuitry may include a usage scenario detection circuit and a content displacement compensation calculation circuit. The usage scenario detection circuit receives data from the sensors and infers a usage scenario based on the sensor data. The content displacement compensation calculation circuit uses the inferred usage scenario to compute a displacement amount by which to adjust image content. When motion stops, the image content may gradually drift back to the center of the display.