Abstract:
An electronic device such as a watch may include a display and a light sensor located behind the display. The light sensor may be used to measure the color of external objects. During color sampling operations, the display may emit light towards the external object in front of the display while the light sensor gathers color measurements. The display may emit light of different colors and the light sensor may detect an amount of reflected light for each color, which in turn may be used to determine the color of the external object. The control circuitry may use a watch-band-specific algorithm to determine the color of watch bands and may use a clothing-specific algorithm to determine the color of clothing. The control circuitry may display the color on the display so that the face of the watch matches the user's clothing or matches the user's watch band.
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:
A display may have an array of organic light-emitting diode display pixels. Each display pixel may include a drive transistor coupled in series with one or more emission transistors and a respective organic light-emitting diode (OLED). A semiconducting-oxide transistor may be coupled between a drain terminal and a gate terminal of the drive transistor to help reduce leakage during low-refresh-rate display operations. To compensate for variations in the threshold voltage of the semiconducting-oxide transistor, the magnitude of a high voltage level of a scan control signal provided to the gate terminal of the semiconducting-oxide transistor may be adjusted. Sensing circuitry may be used to sense a display current while displaying a calibration image. The sensed display current may be compared to an expected display current associated with the calibration image. Processing circuitry may update the high voltage level based on the actual display current compared to the expected display current.
Abstract:
An electronic device may be provided with a display. Backlight structures may be used to provide backlight for the display. The backlight structures may include a light guide plate. A rectangular ring-shaped chassis may have a rectangular opening that receives the light guide plate. One or more edges of the chassis may be provided with an array of notches that receive light-emitting diodes or other light sources. The light sources may launch light into edge portions of the light guide plate. The chassis may include a first plastic structure such as a light reflecting structure formed from a material such as white plastic. The first plastic structure may surround two or more peripheral edges of the light guide plate. The chassis may also include a second plastic structure such as a light blocking structure formed from a material such as black plastic that helps prevent light leakage.
Abstract:
An electronic device may have a display that displays an image. The image may be viewed through a display cover layer that overlaps the display. The display cover layer may include an optical coupling layer such as a coherent fiber bundle. A pixel expansion layer such as a diffractive layer may be incorporated between the optical coupling layer and a protective layer. The diffractive layer may create duplicate pixels to occupy otherwise non-light-emitting areas on the output surface of the display cover layer. The diffractive layer may also create duplicate pixels that overlap adjacent pixels to allow for brightness averaging. An adhesive layer or the protective layer may be used to form diffractive elements for the diffractive layer. An adhesive layer having a high index of refraction may be interposed between the optical coupling layer and the display panel to mitigate undesired reflections of ambient light.
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:
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 electrical components mounted in an electronic device housing. A display module may be attached to a display cover layer with a layer of adhesive to form a display module assembly. The display module assembly may include a display module assembly chassis. The display module assembly chassis may include a plastic display module assembly chassis molded over a metal display module assembly chassis. The display module assembly and a backlight unit may be assembled to form a display module that is installed within the electronic device housing or display module assembly layers and backlight unit structures may be assembled into the electronic device housing. The backlight unit may include a backlight unit chassis. A metal housing midplate may serve as part of the backlight unit chassis.
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 have an array of organic light-emitting diode display pixels. Each display pixel may include a drive transistor coupled in series with one or more emission transistors and a respective organic light-emitting diode (OLED). A semiconducting-oxide transistor may be coupled between a drain terminal and a gate terminal of the drive transistor to help reduce leakage during low-refresh-rate display operations. To compensate for variations in the threshold voltage of the semiconducting-oxide transistor, the magnitude of a high voltage level of a scan control signal provided to the gate terminal of the semiconducting-oxide transistor may be adjusted. Sensing circuitry may be used to sense a display current while displaying a calibration image. The sensed display current may be compared to an expected display current associated with the calibration image. Processing circuitry may update the high voltage level based on the actual display current compared to the expected display current.