Abstract: An organic light-emitting diode display may have thin-film transistor circuitry formed on a substrate. The substrate may have rounded corners, a first tail portion along a lower edge, and a second tail portion along an additional edge. A first plurality of signal paths for the display may be routed to the first tail portion and a second plurality of signal paths for the display may be routed to the second tail portion. The second tail portion may be formed within a pixel-free notched region of the substrate. One or more data lines, power supply lines, touch sensor signal lines, and other signal lines may be routed to the second tail portion. Each tail portion of the substrate may be planar or may be bent. Vertical data lines at the edge of the display may be coupled to data line extensions that are routed through the active area of the display.

Abstract: A display may have an active area that includes display pixels. The display may include an inactive notch region that extends into the active area. Data lines may provide image data from display driver circuitry to the display pixels. The image data may include data signals that correspond to portions of the display that do not include pixels, such as the inactive notch region. The null data signals may cause nonuniformities in the displayed image. The null data signals may be adjusted to minimize the nonuniformities. Null data signals corresponding to the inactive notch region may be adjusted to have gray levels that gradually decrease with distance from the border between the inactive notch and the active area. All of the data signals corresponding to the inactive notch may be set to a uniform gray level.

Abstract: An electronic device may be provided with a display. The display may be a variable frame rate display capable of adaptively adjusting a frame rate at which display frames are displayed in response to information associated with the current state of operation of the device. The information may be gathered using control circuitry in the electronic device. The control circuitry may gather the information for adjusting the frame rate by monitoring the electronic device power supply configuration, other device components, the type of content to be displayed, and user-input signals. The control circuitry may adjust the frame rate based on the gathered information by increasing or decreasing the frame rate. The control circuitry may be formed as a portion of display control circuitry for the device such as a display driver integrated circuit or may be formed as a portion of storage and processing circuitry external to the display.

Abstract: A display may have an active area that includes display pixels. The display may include an inactive notch region that extends into the active area. Data lines may provide image data from display driver circuitry to the display pixels. The image data may include data signals that correspond to portions of the display that do not include pixels, such as the inactive notch region. The null data signals may cause nonuniformities in the displayed image. The null data signals may be adjusted to minimize the nonuniformities. Null data signals corresponding to the inactive notch region may be adjusted to have gray levels that gradually decrease with distance from the border between the inactive notch and the active area. All of the data signals corresponding to the inactive notch may be set to a uniform gray level.

Abstract: An electronic device may be provided with a display. The display may be a variable frame rate display capable of adaptively adjusting a frame rate at which display frames are displayed in response to information associated with the current state of operation of the device. The information may be gathered using control circuitry in the electronic device. The control circuitry may gather the information for adjusting the frame rate by monitoring the electronic device power supply configuration, other device components, the type of content to be displayed, and user-input signals. The control circuitry may adjust the frame rate based on the gathered information by increasing or decreasing the frame rate. The control circuitry may be formed as a portion of display control circuitry for the device such as a display driver integrated circuit or may be formed as a portion of storage and processing circuitry external to the display.

Abstract: Display structures for controlling viewing angle color shift are described. In various embodiments, polarization sensitive diffusers, independent controlled cathode thicknesses, filtermasks, and color filters are described.

Abstract: Display structures for controlling viewing angle color shift are described. In various embodiments, polarization sensitive diffusers, independent controlled cathode thicknesses, filtermasks, touch detection layers, and color filters are described.

Abstract: A display may have an active area that includes display pixels. The display may include an inactive notch region that extends into the active area. Data lines may provide image data from display driver circuitry to the display pixels. The image data may include data signals that correspond to portions of the display that do not include pixels, such as the inactive notch region. The null data signals may cause nonuniformities in the displayed image. The null data signals may be adjusted to minimize the nonuniformities. Null data signals corresponding to the inactive notch region may be adjusted to have gray levels that gradually decrease with distance from the border between the inactive notch and the active area. All of the data signals corresponding to the inactive notch may be set to a uniform gray level.

Abstract: A thin-film transistor layer, an organic light-emitting diode layer, and other layers may be used in forming an array of pixels on a substrate in a display. Vias may be formed through one or more layers of the display such as the substrate layer to form vertical signal paths. The vertical signal paths may convey signals between display driver circuitry underneath the display and the pixels. The vias may pass through a polymer layer and may contact pads formed within openings in the substrate. Vias may pass through a glass support layer. Metal traces may be formed in the thin-film transistor layer to create signal paths such as data lines and gate lines. Portions of the metal traces may form vias through a polymer layer such as a substrate layer or a polymer layer that has been formed on top of the substrate layer.

Abstract: An electronic device may be provided with a display. A content generator may generate frames of image data to be displayed on the display. The display may have an array of pixels that emit light to display images. The pixels may contain light-emitting devices such as organic light-emitting diodes, quantum dot light-emitting diodes, and light-emitting diodes formed from discrete semiconductor dies. As a result of aging, the light producing capabilities of the light-emitting devices may degrade over time. The electronic device may have a temperature sensor that gathers temperature measurements. A pixel luminance degradation compensator may apply compensation factors to uncorrected pixel luminance values associated with the frames of image data to produce corresponding corrected pixel luminance values for the display. The compensation factors may be based on aging history information such as pixel luminance history and temperature measurements.

Abstract: An electronic device may be provided with a display. The display may be a variable frame rate display capable of adaptively adjusting a frame rate at which display frames are displayed in response to information associated with the current state of operation of the device. The information may be gathered using control circuitry in the electronic device. The control circuitry may gather the information for adjusting the frame rate by monitoring the electronic device power supply configuration, other device components, the type of content to be displayed, and user-input signals. The control circuitry may adjust the frame rate based on the gathered information by increasing or decreasing the frame rate. The control circuitry may be formed as a portion of display control circuitry for the device such as a display driver integrated circuit or may be formed as a portion of storage and processing circuitry external to the display.

Abstract: An organic light-emitting diode display may have an active area that contains pixels and an inactive area. The inactive area of the display may be provided with opaque masking layer structures having an appearance that matches the active area of the display when the pixels are off and are not displaying images. The opaque masking layer structures may include a polymer layer coated with a layer of metal. The display may have pixels with anodes and a cathode layer. The anodes may be formed from metal pads. Dummy structures such as a dummy cathode and dummy anodes may be formed in the inactive area. A circular polarizer in the display may overlap the active area and the inactive area or may overlap the active area without overlapping some or all of the inactive area.

Abstract: An electronic device may be provided with a display. The display may be a variable frame rate display capable of adaptively adjusting a frame rate at which display frames are displayed in response to information associated with the current state of operation of the device. The information may be gathered using control circuitry in the electronic device. The control circuitry may gather the information for adjusting the frame rate by monitoring the electronic device power supply configuration, other device components, the type of content to be displayed, and user-input signals. The control circuitry may adjust the frame rate based on the gathered information by increasing or decreasing the frame rate. The control circuitry may be formed as a portion of display control circuitry for the device such as a display driver integrated circuit or may be formed as a portion of storage and processing circuitry external to the display.

Abstract: An organic light-emitting diode display may have an active area that contains pixels and an inactive area. The inactive area of the display may be provided with opaque masking layer structures having an appearance that matches the active area of the display when the pixels are off and are not displaying images. The opaque masking layer structures may include a polymer layer coated with a layer of metal. The display may have pixels with anodes and a cathode layer. The anodes may be formed from metal pads. Dummy structures such as a dummy cathode and dummy anodes may be formed in the inactive area. A circular polarizer in the display may overlap the active area and the inactive area or may overlap the active area without overlapping some or all of the inactive area.

Abstract: An organic light-emitting diode display may have an active area that contains pixels and an inactive area. The inactive area of the display may be provided with opaque masking layer structures having an appearance that matches the active area of the display when the pixels are off and are not displaying images. The opaque masking layer structures may include a polymer layer coated with a layer of metal. The display may have pixels with anodes and a cathode layer. The anodes may be formed from metal pads. Dummy structures such as a dummy cathode and dummy anodes may be formed in the inactive area. A circular polarizer in the display may overlap the active area and the inactive area or may overlap the active area without overlapping some or all of the inactive area.

Abstract: An electronic device includes a transparent surface, a light emitting device that emits light through the transparent surface, and a light sensor for receiving ambient light and providing an ambient light value. A retarder and a linear polarizer are placed between the transparent surface and the light emitting device. The retarder and linear polarizer may attenuate internal reflections from the transparent surface. The light sensor may have two channels and a second linear polarizer may attenuate the ambient light directed toward a second channel. A second retarder may be used with the second linear polarizer to attenuate the ambient light directed toward the second channel. A light detection circuit may use the difference between the two channels of the light sensor to provide the ambient light value.

Abstract: An electronic device may be provided with a display. A content generator may generate frames of image data to be displayed on the display. The display may have an array of pixels that emit light to display images. The pixels may contain light-emitting devices such as organic light-emitting diodes, quantum dot light-emitting diodes, and light-emitting diodes formed from discrete semiconductor dies. As a result of aging, the light producing capabilities of the light-emitting devices may degrade over time. The electronic device may have a temperature sensor that gathers temperature measurements. A pixel luminance degradation compensator may apply compensation factors to uncorrected pixel luminance values associated with the frames of image data to produce corresponding corrected pixel luminance values for the display. The compensation factors may be based on aging history information such as pixel luminance history and temperature measurements.

Abstract: An organic light-emitting diode display may have an active area that contains pixels and an inactive area. The inactive area of the display may be provided with opaque masking layer structures having an appearance that matches the active area of the display when the pixels are off and are not displaying images. The opaque masking layer structures may include a polymer layer coated with a layer of metal. The display may have pixels with anodes and a cathode layer. The anodes may be formed from metal pads. Dummy structures such as a dummy cathode and dummy anodes may be formed in the inactive area. A circular polarizer in the display may overlap the active area and the inactive area or may overlap the active area without overlapping some or all of the inactive area.

Abstract: A display may receive image data to be displayed for a user of an electronic device. Display driver circuitry in the display may analyze the data to detect static data. The image data may contain static frames of data or static portions of a frame of data. In response to detection of static data, the display driver circuitry can take actions to avoid display damage due to burn-in effects. The display driver circuitry may reduce a peak luminance value associated with a peak luminance control algorithm, may reduce display brightness, may map image data to reduced brightness levels, or may take other actions to ensure that display pixels in the display are not damaged. Temperature information may be used in determining how to classify information as static data and in determining how significantly to reduce display pixel drive currents in response to the detection of static image data.

Abstract: A thin-film transistor layer, an organic light-emitting diode layer, and other layers may be used in forming an array of pixels on a substrate in a display. Vias may be formed through one or more layers of the display such as the substrate layer to form vertical signal paths. The vertical signal paths may convey signals between display driver circuitry underneath the display and the pixels. The vias may pass through a polymer layer and may contact pads formed within openings in the substrate. Vias may pass through a glass support layer. Metal traces may be formed in the thin-film transistor layer to create signal paths such as data lines and gate lines. Portions of the metal traces may form vias through a polymer layer such as a substrate layer or a polymer layer that has been formed on top of the substrate layer.