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 organic light-emitting diode display may have thin-film transistor circuitry formed on a substrate. The display and substrate may have rounded corners. A pixel definition layer may be formed on the thin-film transistor circuitry. Openings in the pixel definition layer may be provided with emissive material overlapping respective anodes for organic light-emitting diodes. A cathode layer may cover the array of pixels. A ground power supply path may be used to distribute a ground voltage to the cathode layer. The ground power supply path may be formed from a metal layer that is shorted to the cathode layer using portions of a metal layer that forms anodes for the diodes, may be formed from a mesh shaped metal pattern, may have L-shaped path segments, may include laser-deposited metal on the cathode layer, and may have other structures that facilitate distribution of the ground power supply.

Abstract: Systems and methods reduce likelihood of hysteresis that reduces perceived image quality of a subsequent image frame by toggling the display pixels to relax the display pixels by overwriting previous image frame data. During non-emission periods of the pixels, the pixels may be pre-toggled or exercised to improve response time and accuracy of the pixel. Data for pixels being programmed may also be used to pre-toggle other pixels reducing overhead but increasing cross-talk. Since the amount of cross-talk is related to content of the pixels being pre-toggled, a line buffer may be used to store image data for the pixels being pre-toggled. This stored image data may be used to determine how much pre-compensation is to be applied to data for the pixels being programmed. In other words, an amount of compensation applied is based at least in part on the content (e.g., greyscale levels) of the image data.

Abstract: A display may have an array of pixels. Display driver circuitry may supply data and control signals to the pixels. Each pixel may have seven transistors, a capacitor, and a light-emitting diode such as an organic light-emitting diode. The seven transistors may receive control signals using horizontal control lines. Each pixel may have first and second emission enable transistors that are coupled in series with a drive transistor and the light-emitting diode of that pixel. The first and second emission enable transistors may be coupled to a common control line or may be separately controlled so that on-bias stress can be effectively applied to the drive transistor. The display driver circuitry may have gate driver circuits that provide different gate line signals to different rows of pixels within the display. Different rows may also have different gate driver strengths and different supplemental gate line loading structures.

Abstract: An organic light-emitting diode display may have thin-film transistor circuitry formed on a substrate. The display and substrate may have rounded corners. A pixel definition layer may be formed on the thin-film transistor circuitry. Openings in the pixel definition layer may be provided with emissive material overlapping respective anodes for organic light-emitting diodes. A cathode layer may cover the array of pixels. A ground power supply path may be used to distribute a ground voltage to the cathode layer. The ground power supply path may be formed from a metal layer that is shorted to the cathode layer using portions of a metal layer that forms anodes for the diodes, may be formed from a mesh shaped metal pattern, may have L-shaped path segments, may include laser-deposited metal on the cathode layer, and may have other structures that facilitate distribution of the ground power supply.

Abstract: An electronic device may include a display such as a light-emitting diode display. The electronic device may be a head-mounted device that provides a virtual reality or augmented reality environment to a user. To reduce artifacts in the display, a display may be operable in both a normal scanning mode and a partial scanning mode. In the normal scanning mode, every row of the display may be enabled to emit light in each frame. In the partial scanning mode, only a subset of the rows of the display may be enabled to emit light in each frame. The display may have a higher refresh rate in the partial scanning mode than in the normal scanning mode. To ensure uniform transistor stress across the display, the scanning driver for the display may scan the disabled rows in the partial scanning mode even though the rows will not be used to emit light.

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: To minimize the width of a non-light-emitting border region around an opening in the active area, data lines may be stacked in the border region. Data line portions may be formed using three metal layers in three different planes within the border region. A metal layer that forms a positive power signal distribution path in the active area may serve as a data line portion in the border region. A metal layer may be added in the border region to serve as a data line portion in the border region. Data line signals may also be provided to pixels on both sides of an opening in the active area using supplemental data line paths. A supplemental data line path may be routed through the active area of the display to electrically connect data line segments on opposing sides of an opening within the display.

Abstract: A display may have an array of pixels. Due to the presence of a notch in the display, the display may have some rows that are shorter than other rows in the display, and accordingly different gate line loading. To account for the gate line loading variations, the display driver circuitry may have gate driver circuits that provide different gate line signals to different rows of pixels within the display. In other arrangement, luminance adjustment circuitry may receive image data and generate corresponding compensated image data to account for gate line loading variations between rows of pixels in the display. The image data may be compensated based on the location of the pixel, the gray level of the image data, the display brightness, and/or temperature.

Abstract: Electronic devices, storage medium containing instructions, and methods pertain to cancelling noise that results from application of clocks/clock drivers of a display. The electronic display may inject counter noise into the cathode. For example, the counter noise may be injected via a sensing layer, via unused clocks, and/or via a power rail of the display.

Abstract: A touch sensor panel is disclosed. In some examples, the touch sensor panel includes drive electrodes and sense electrodes, wherein the drive electrodes and sense electrodes form touch nodes. In some examples, touch nodes include differently-sized drive and/or sense electrodes, and changes to the size or quantity of reference or floating electrodes disposed within the drive and/or sense electrodes are used to substantially balance the areas of the drive and/or sense electrodes in a given touch node.

Abstract: An electronic device may include a display such as a light-emitting diode display. The electronic device may be a head-mounted device that provides a virtual reality or augmented reality environment to a user. To reduce artifacts in the display, a display may be operable in both a normal scanning mode and a partial scanning mode. In the normal scanning mode, every row of the display may be enabled to emit light in each frame. In the partial scanning mode, only a subset of the rows of the display may be enabled to emit light in each frame. The display may have a higher refresh rate in the partial scanning mode than in the normal scanning mode. To ensure uniform transistor stress across the display, the scanning driver for the display may scan the disabled rows in the partial scanning mode even though the rows will not be used to emit light.

Abstract: An electronic device may include a display such as a light-emitting diode display. The electronic device may be a head-mounted device that provides a virtual reality or augmented reality environment to a user. To reduce artifacts in the display, a display may be operable in both a normal scanning mode and a partial scanning mode. In the normal scanning mode, every row of the display may be enabled to emit light in each frame. In the partial scanning mode, only a subset of the rows of the display may be enabled to emit light in each frame. The display may have a higher refresh rate in the partial scanning mode than in the normal scanning mode. To ensure uniform transistor stress across the display, the scanning driver for the display may scan the disabled rows in the partial scanning mode even though the rows will not be used to emit light.

Abstract: An organic light-emitting diode display may have rounded corners. A negative power supply path may be used to distribute a negative voltage to a cathode layer, while a positive power supply path may be used to distribute a positive power supply voltage to each pixel in the display. The positive power supply path may have a cutout that is occupied by the negative power supply path to decrease resistance of the negative power supply path in a rounded corner of the display. To mitigate reflections caused by the positive power supply path being formed over tightly spaced data lines, the positive power supply path may be omitted in a rounded corner of the display, a shielding layer may be formed over the positive power supply path in the rounded corner, or non-linear gate lines may be formed over the positive power supply path.

Abstract: An electronic device may include a display such as a light-emitting diode display. The electronic device may be a head-mounted device that provides a virtual reality or augmented reality environment to a user. To reduce artifacts in the display, a display may be operable in both a normal scanning mode and a partial scanning mode. In the normal scanning mode, every row of the display may be enabled to emit light in each frame. In the partial scanning mode, only a subset of the rows of the display may be enabled to emit light in each frame. The display may have a higher refresh rate in the partial scanning mode than in the normal scanning mode. To ensure uniform transistor stress across the display, the scanning driver for the display may scan the disabled rows in the partial scanning mode even though the rows will not be used to emit light.

Abstract: Systems and methods reduce likelihood of hysteresis that reduces perceived image quality of a subsequent image frame by toggling the display pixels to relax the display pixels by overwriting previous image frame data. During non-emission periods of the pixels, the pixels may be pre-toggled or exercised to improve response time and accuracy of the pixel. Data for pixels being programmed may also be used to pre-toggle other pixels reducing overhead but increasing cross-talk. Since the amount of cross-talk is related to content of the pixels being pre-toggled, a line buffer may be used to store image data for the pixels being pre-toggled. This stored image data may be used to determine how much pre-compensation is to be applied to data for the pixels being programmed. In other words, an amount of compensation applied is based at least in part on the content (e.g., greyscale levels) of the image data.

Abstract: Aspects of the subject technology relate to display circuitry. The display circuitry includes gate-in-panel (GIP) control circuitry on opposing sides of a display pixel array. The GIP control circuitry can include scan drivers for each pixel row on both sides of that pixel row, the scan drivers on either side configured for enablement or disablement for single-sided reduced-power operations. The GIP control circuitry can include a single scan driver and a single emission controller for each pixel row, in which the scan driver and emission controller for each row are disposed on opposing sides of the row. The scan drivers for a first subset of the pixel rows can be interleaved with the emission controllers for a different subset of the pixel rows.

Abstract: Electronic devices, storage medium containing instructions, and methods pertain to cancelling noise that results from application of voltages on gates of transistors in a display. One or more compensation or dummy drivers are used to apply a compensation voltage that is an inversion of voltages applied on the gates of the transistors.

Abstract: An organic light-emitting diode display may have thin-film transistor circuitry formed on a substrate. The display and substrate may have rounded corners. A pixel definition layer may be formed on the thin-film transistor circuitry. Openings in the pixel definition layer may be provided with emissive material overlapping respective anodes for organic light-emitting diodes. A cathode layer may cover the array of pixels. A ground power supply path may be used to distribute a ground voltage to the cathode layer. The ground power supply path may be formed from a metal layer that is shorted to the cathode layer using portions of a metal layer that forms anodes for the diodes, may be formed from a mesh shaped metal pattern, may have L-shaped path segments, may include laser-deposited metal on the cathode layer, and may have other structures that facilitate distribution of the ground power supply.

Abstract: An organic light-emitting diode display may have an array of pixels. The pixels may each have an organic light-emitting diode with a respective anode and may be formed from thin-film transistor circuitry formed on a substrate. A mesh-shaped path may be used to distribute a power supply voltage to the thin-film circuitry. The mesh-shaped path may have intersecting horizontally extending lines and vertically extending lines. The horizontally extending lines may be zigzag metal lines that do not overlap the anodes. The vertically extending lines may be straight vertical metal lines that overlap the anodes. The pixels may include pixels of different colors. Angularly dependent shifts in display color may be minimized by ensuring that the anodes of the differently colored pixels overlap the vertically extending lines by similar amounts.