Abstract:
Systems, methods, and computer-readable media for determining the temperature of a light-generating component of a display assembly using a voltage of the light-generating component are provided. In one embodiment, a method for operating an electronic device, which may include an external surface and a light-emitting diode operative to emit light for illuminating the external surface, may include detecting the forward voltage of the light-emitting diode, calculating the temperature of the light-emitting diode using the detected forward voltage of the light-emitting diode, and altering the performance of the electronic device based on the calculated temperature of the light-emitting diode. Additional embodiments are also provided.
Abstract:
An electronic device may have a display mounted in a housing. The display may have a pixel array that produces images. A display cover layer may overlap the pixel array. The display cover layer may have a planar central area surrounded by a peripheral edge area with a curved cross-sectional profile. From an on-axis viewing angle, an image on the pixel array is fully viewable through the planar central area and the peripheral edge area. From an off-axis viewing angle, the image is partly viewable through the peripheral edge area and not through the central area. To avoid an undesired color cast in the partly viewable image seen through the peripheral edge area of the display cover layer, the display may be provided with color cast compensation structures such as a guest-host liquid crystal layer that exhibits an anisotropic colored light absorption characteristic, a diffuser layer, and/or other optical structures.
Abstract:
A display may be formed by an array of light-emitting diodes mounted to the surface of a display substrate. The light-emitting diodes may be inorganic light-emitting diodes formed from separate crystalline semiconductor structures. An array of pixel control circuits may be used to control light emission from the light-emitting diodes. Each pixel control circuit may be configured to control one or more respective passive matrices. To control partial pixel cells in the display, a donor pixel control circuit in a partial pixel cell may control the pixels in a receptor partial pixel cell without a pixel control circuit. To mitigate the size of an inactive area of the display, fanout signal lines for the display may be formed in the light-emitting active area of the display. The fanout signal lines may be formed between a row of pixel control circuits and a bottom edge of the light-emitting active area.
Abstract:
An electronic device such as a wearable electronic device may have a band. The band may form a stand-alone device or a strap for a wristwatch unit or other device. Electrical components may be mounted on flexible printed circuit substrates. A substrate may be encapsulated by elastomeric polymer material or other material forming the band. The elastomeric polymer material may form cavities that receive the electrical components. Components such as light-emitting diodes may be mounted to the flexible printed circuit substrates so that the light-emitting diodes are located in the cavities. Reflective sidewalls in the cavities may reflect light from the light-emitting diodes outwardly through a thinned portion of the band. Light-diffusing material in the cavities may be formed from clear polymer with light-scattering particles.
Abstract:
An electronic device may include an electronic display including display pixels to display an image based on compensated image data. The electronic display may also include a stressed reference pixel to exhibit burn-in related aging in response to one or more stress sessions and a non-stressed reference pixel configured to not undergo the one or more stress sessions. Additionally, the electronic device may include image processing circuitry to determine a panel-specific aging profile based on a comparison between one or more properties of the stressed reference pixel and the one or more properties of the non-stressed reference pixel. The image processing circuitry may also generate one or more gain maps based on the panel-specific aging profile and generate the compensated image data by applying the one or more gain maps to input image data.
Abstract:
An electronic device may generate content that is to be displayed on a display. The display may have an array of liquid crystal display pixels for displaying image frames of the content. The display may be operated in at least a normal viewing mode, a privacy mode, an outdoor viewing mode, and a power saving mode. The different view modes may exhibit different viewing angles. In one configuration, the display may include a backlight unit that generates a collimated light source and that includes a switchable diffuser film for selectively scattering the collimated light source depending on the current viewing mode of the display. In another configuration, the display may include a backlight unit that generates a scattered light source that includes a switchable microarray structure such as a switchable mirror structure or a tunable microlens array for selectively collimating the scattered light source depending on the current viewing mode.
Abstract:
A display may have a backlight unit with a row of light-emitting diodes that emit light into the edge of a light guide plate. The light guide plate may have opposing upper and lower surfaces. The upper surface of the light guide plate may have ridges and the lower surface of the light guide plate may have bumps. The edge of the light guide plate may have light mixing structures. The light mixing structures may include edge surfaces that refract light at a high angle. The high angle light may then be reflected by a reflective surface so that the light propagates down the light guide plate. Some light may pass through the light mixing structures and propagate down the light guide plate without being reflected by the reflective surface. This arrangement may reduce the mixing distance of the backlight unit.
Abstract:
An electronic device may be provided with a display having a backlight with light sources of different colors. The electronic device may include a color ambient light sensor that measures the color of ambient light and control circuitry that adjusts the color of light emitted from the backlight based on the color of ambient light. The light sources may include at least first and second light-emitting diodes that emit light having different color temperatures. The control circuitry may adjust the intensity of light emitted from the first light-emitting diode relative to the intensity of light emitted from the second light-emitting diode to produce a backlight color that more closely matches the color of ambient light. The first and second light-emitting diodes may include an ultraviolet light-emitting diode die and a blue light-emitting diode die that are mounted in a common semiconductor package.
Abstract:
Systems, methods, and computer-readable media for determining the temperature of a light-generating component of a display assembly using a voltage of the light-generating component are provided. In one embodiment, a method for operating an electronic device, which may include an external surface and a light-emitting diode operative to emit light for illuminating the external surface, may include detecting the forward voltage of the light-emitting diode, calculating the temperature of the light-emitting diode using the detected forward voltage of the light-emitting diode, and altering the performance of the electronic device based on the calculated temperature of the light-emitting diode. Additional embodiments are also provided.
Abstract:
An electronic device may be provided with a display. The display may include a liquid crystal display cell and an organic light-emitting diode backlight unit. The liquid crystal display cell may include a color filter layer, a liquid crystal layer, and a thin-film transistor layer. The organic light-emitting diode backlight unit may include organic emissive material formed on a substrate. The organic emissive material may generate backlight for liquid crystal display cell. Display pixels in the liquid crystal display cell may control the emission of the backlight from the display. The organic light-emitting diode backlight unit may be attached to the display using adhesive, laminated to a polarizer layer of the display cell, or may be integrated into the liquid crystal display cell. The backlight unit may include conductive vias or bent extended edge portions for coupling the backlight unit to control circuitry.